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1

Removal of fluoride from aqueous nitric acid  

SciTech Connect (OSTI)

Several methods for removing fluoride from aqueous nitric acid were investigated and compared with the frequently used aluminum nitrate-calcium nitrate (Ca/sup 2 +/-Al/sup 3 +/) chemical trap-distillation system. Zirconium oxynitrate solutions were found to be superior in preventing volatilization of fluoride during distillation of the nitric acid, producing decontamination factors (DFs) on the order of 2 x 10/sup 3/ (vs approx. 500 for the Ca/sup 2 +/-Al/sup 3 +/ system). Several other metal nitrate systems were tested, but they were less effective. Alumina and zirconia columns proved highly effective in removing HF from HF-HNO/sub 3/ vapors distilled through the columns; fluoride DFs on the order of 10/sup 6/ and 10/sup 4/, respectively, were obtained. A silica gel column was very effective in adsorbing HF from HF-HNO/sub 3/ solutions, producing a fluoride DF of approx. 10/sup 4/.

Pruett, D.J.; Howerton, W.B.; Mailen, J.C.

1981-06-01T23:59:59.000Z

2

Butane segregated by fluorides, olefins content at Texas terminals  

SciTech Connect (OSTI)

Texas Eastern Products Pipeline Co., Houston (Teppco), this month has begun segregating butane streams at the company's Mont Belvieu and Baytown, Texas terminals according to fluoride and olefin contents. Streams containing fluoride or an olefin content greater than 1 ppm (or both) currently flow into Teppco's south Mont Belvieu terminal. Those fluoride-free streams with less than 1 ppm of olefins flow to its north Mont Belvieu terminal. Butane processed through an isomerization unit yields isobutane, a key component in MTBE. But high-fluoride butane from crude-oil refineries using hydrofluoric (HF) acid alkylation units cannot be used to produce MTBE because fluoride will damage isomerization units' process catalysts. Olefins also affect the efficiency of isomerization units, but less critically than fluorides. Their presence is higher in refinery product than in fractionated NGL. To extend the life of their process catalysts and to maximize yields, producers (including MTBE and isomerization unit operators) are specifying low-fluoride butanes developed from natural-gas fractionators or from refineries that do not use an HF process.

Not Available

1993-03-22T23:59:59.000Z

3

Identification of aluminum scale with the aid of synthetically produced basic aluminum fluoride complexes  

SciTech Connect (OSTI)

Aluminum scaling can be a problem following HF acidizing. In this paper, a series of synthetic aluminum scales was prepared and identified. The aluminum compounds of a field scale were identified with similar procedures. Recent field work showed that the use of acetic acid in the HF acidizing sequences significantly decreased scaling. The role of acetic acid is discussed on the basis of laboratory support of these field data.

Shuchart, C.E. (Halliburton Services, Duncan, OK (United States)); Ali, S.A. (Chevron U.S.A. Inc., New Orleans, LA (United States))

1993-11-01T23:59:59.000Z

4

HF separation in a carbonylation process  

SciTech Connect (OSTI)

This patent describes the carbonylation of an olefin with carbon monoxide in the presence of hydrogen fluoride catalyst wherein the reaction product is treated with water to produce a mixture of a carboxylic acid, HF and optionally water. The improvement comprises contacting at a temperature in the range of from about 25/sup 0/C up to about 100/sup 0/C, the mixture with one side of a cation permeable membrane of a copolymer of tetrafluoro ethylene and perfluoro-3, 6-dioxa-4-methyl-octen sulfamic acid whose other side is in contact with water.

Grote, D.; Trivedi, B.C.; Mason, T.O.

1987-04-28T23:59:59.000Z

5

Process for converting magnesium fluoride to calcium fluoride  

DOE Patents [OSTI]

This invention is a process for the conversion of magnesium fluoride to calcium fluoride whereby magnesium fluoride is decomposed by heating in the presence of calcium carbonate, calcium oxide or calcium hydroxide. Magnesium fluoride is a by-product of the reduction of uranium tetrafluoride to form uranium metal and has no known commercial use, thus its production creates a significant storage problem. The advantage of this invention is that the quality of calcium fluoride produced is sufficient to be used in the industrial manufacture of anhydrous hydrogen fluoride, steel mill flux or ceramic applications.

Kreuzmann, A.B.; Palmer, D.A.

1984-12-21T23:59:59.000Z

6

Method of making porous ceramic fluoride  

SciTech Connect (OSTI)

A process is disclosed for making a porous ceramic composite where fumed silica particles are coated with a nitrate, preferably aluminum nitrate. Next the nitrate is converted to an oxide and formed into a desired configuration. This configuration is heated to convert the oxide to an oxide silicate which is then react with HF, resulting in the fluoride ceramic, preferably aluminum fluoride.

Reiner, R.H.; Holcombe, C.E.

1990-11-13T23:59:59.000Z

7

Method of making porous ceramic fluoride  

DOE Patents [OSTI]

A process for making a porous ceramic composite where fumed silica particles are coated with a nitrate, preferably aluminum nitrate. Next the nitrate is converted to an oxide and formed into a desired configuration. This configuration is heated to convert the oxide to an oxide silicate which is then react with HF, resulting in the fluoride ceramic, preferably aluminum fluoride.

Reiner, Robert H. (Knoxville, TN); Holcombe, Cressie E. (Farragut, TN)

1990-01-01T23:59:59.000Z

8

E-Print Network 3.0 - acid nitrosyl fluoride Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

nitrosyl hydride CN cyanide radical HF hydrogen fluoride hydrogen ion* carbon monoxide ion sulfur monoxide... with 8 atoms HCCN acetic acid methyl formate methyl radical*...

9

Chemical emergency preparedness and prevention advisory: Hydrogen fluoride, series 8, No. 3  

SciTech Connect (OSTI)

The advisory recommends ways Local Emergency Planning Committees (LEPCs) and chemical facilities can reduce risks posed by the presence of hydrogen fluoride (HF) in their communities. Hydrogen fluoride, a strong inorganic acid, is produced and used as a gas or liquid without water (i.e., in anhydrous form), or in a water (aqueous) solution. Inhalation of hydrogen fluoride vapor, either in anhydrous form or from water solutions, can cause irritation if the exposure is mild (i.e., low concentration in air for a short time), or severe damage to the respiratory system or death in the case of exposure to high concentrations. Contact with the liquid or vapor can severely burn the skin, eyes, and other tissue. The largest use of hydrogen fluoride is in the manufacture of fluorine-containing chemicals, particularly chlorofluorocarbons (CFCs). Hydrogen fluoride may be used in some petroleum refinery operations, aluminum production, nuclear applications, glass etching and polishing, and metal treating and cleaning. Hydrogen fluoride's acute toxicity prompted EPA to list it as an extremely hazardous substance (EHS), with a threshold planning quantity (TPQ) of 100 pounds, under Section 302 of the Emergency Planning and Community Right-to-Know Act (commonly known as SARA Title III).

Not Available

1993-07-01T23:59:59.000Z

10

Divalent fluoride doped cerium fluoride scintillator  

DOE Patents [OSTI]

The use of divalent fluoride dopants in scintillator materials comprising cerium fluoride is disclosed. The preferred divalent fluoride dopants are calcium fluoride, strontium fluoride, and barium fluoride. The preferred amount of divalent fluoride dopant is less than about two percent by weight of the total scintillator. Cerium fluoride scintillator crystals grown with the addition of a divalent fluoride have exhibited better transmissions and higher light outputs than crystals grown without the addition of such dopants. These scintillators are useful in radiation detection and monitoring applications, and are particularly well suited for high-rate applications such as positron emission tomography (PET).

Anderson, David F. (630 Sylvan Pl., Batavia, IL 60510); Sparrow, Robert W. (28 Woodlawn Dr., Sturbridge, MA 01566)

1991-01-01T23:59:59.000Z

11

Fabrication of nanoscale patterns in lithium fluoride crystal using a 13.5 nm Schwarzschild objective and a laser produced plasma source  

SciTech Connect (OSTI)

Lithium fluoride (LiF) crystal is a radiation sensitive material widely used as EUV and soft x-ray detector. The LiF-based detector has high resolution, in principle limited by the point defect size, large field of view, and wide dynamic range. Using LiF crystal as an imaging detector, a resolution of 900 nm was achieved by a projection imaging of test meshes with a Schwarzschild objective operating at 13.5 nm. In addition, by imaging of a pinhole illuminated by the plasma, an EUV spot of 1.5 {mu}m diameter in the image plane of the objective was generated, which accomplished direct writing of color centers with resolution of 800 nm. In order to avoid sample damage and contamination due to the influence of huge debris flux produced by the plasma source, a spherical normal-incidence condenser was used to collect EUV radiation. Together with a description of experimental results, the development of the Schwarzschild objective, the influence of condenser on energy density and the alignment of the imaging system are also reported.

Wang Xin [Key Laboratory of Advanced Micro-structured Materials, MOE, Department of Physics, Institute of Precision Optical Engineering, Tongji University, Shanghai 200092 (China); School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092 (China); Mu Baozhong; Jiang Li; Zhu Jingtao; Yi Shengzhen; Wang Zhanshan [Key Laboratory of Advanced Micro-structured Materials, MOE, Department of Physics, Institute of Precision Optical Engineering, Tongji University, Shanghai 200092 (China); He Pengfei [School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092 (China)

2011-12-15T23:59:59.000Z

12

Magnesium fluoride recovery method  

DOE Patents [OSTI]

A method of obtaining magnesium fluoride substantially free from radioactive uranium from a slag containing the same and having a radioactivity level of at least about 7000 pCi/gm. The slag is ground to a particle size of about 200 microns or less. The ground slag is contacted with an acid under certain prescribed conditions to produce a liquid product and a particulate solid product. The particulate solid product is separated from the liquid and treated at least two more times with acid to produce a solid residue consisting essentially of magnesium fluoride substantially free of uranium and having a residual radioactivity level of less than about 1000 pCi/gm. In accordance with a particularly preferred embodiment of the invention a catalyst and an oxidizing agent are used during the acid treatment and preferably the acid is sulfuric acid having a strength of about 1.0 Normal.

Gay, Richard L. (Canoga Park, CA); McKenzie, Donald E. (Woodland Hills, CA)

1989-01-01T23:59:59.000Z

13

Sol-gel synthesis of high-quality heavy-metal fluoride glasses  

SciTech Connect (OSTI)

Fluoride glasses are excellent laser hosts and are very well suited for a broad spectrum of optical applications. However, current fluoride glass synthesis is expensive. The sol-gel method is an affordable alternative for producing high-performance, optical-quality heavy-metal fluoride glasses. The method involves forming a hydrous oxide gel of the constituent metal alkoxides and salts, polymerizing the solution to form a gel, fluorinating the gel with anhydrous HF, melting the amorphous material in an oxidizing atmosphere of SF[sub 6], and casting the melt into desired shapes. ZBLA (57ZrF[sub 4] [times] 36BaF[sub 2] [times] 4LaF[sub 3] [times] 3AlF[sub 3], in mol%) and Nd-doped (0.3 mol%) ZBLA glass rods were prepared by this process and their properties were measured. The sol-gel-based glasses had thermal and optical properties similar to those found in the literature for conventionally prepared fluorides.

Dejneka, M.; Riman, R.E.; Snitzer, E. (Rutgers, The State Univ. of New Jersey, Piscataway, NJ (United States). Dept. of Ceramics)

1993-12-01T23:59:59.000Z

14

Fluorohydrogenate Cluster Ions in the Gas Phase: Electrospray Ionization Mass Spectrometry of the [1-Ethyl-3-methylimidazolium+][F(HF)2.3–] Ionic Liquid  

SciTech Connect (OSTI)

Electrospray ionization of the fluorohydrogenate ionic liquid [1-ethyl-3-methylimidazolium][F(HF)2.3] ionic liquid was conducted to understand the nature of the anionic species as they exist in the gas phase. Abundant fluorohydrogenate clusters were produced; however, the dominant anion in the clusters was [FHF-], and not the fluoride-bound HF dimers or trimers that are seen in solution. Density functional theory (DFT) calculations suggest that HF molecules are bound to the clusters by about 30 kcal/mol. The DFT-calculated structures of the [FHF-]-bearing clusters show that the favored interactions of the anions are with the methynic and acetylenic hydrogen atoms on the imidazolium cation, forming planar structures similar to those observed in the solid state. A second series of abundant negative ions was also formed that contained [SiF5-] together with the imidazolium cation and the fluorohydrogenate anions that originate from reaction of the spray solution with silicate surfaces.

Gary S. Groenewold; James E. Delmore; Michael T. Benson; Tetsuya Tsuda; Rika Hagiwara

2013-12-01T23:59:59.000Z

15

Method of treating fluoride contaminated wastes  

SciTech Connect (OSTI)

A method for treating spent aluminum smelting potliner material containing fluoride contaminants is described which comprises: adding silica to the material to form a mixture thereof; elevating the temperature of the mixture within the range of 1,000/sup 0/ to 1,700/sup 0/C. to form a slag; providing sufficient silica in the mixture and forming the slag in the presence of sufficient water for pyrohydrolysis conditions resulting in the volatilization of substantially all of the fluoride contaminants mostly in the form of hydrogen fluoride; and cooling the slag remaining after volatilizatiion of substantially all of the fluoride contaminants to produce an insoluble silicate glass-residue containing any remaining portion of the fluoride contaminants in an immobile state.

Davis, P.K.; Kakaria, V.K.

1988-04-05T23:59:59.000Z

16

Uranyl fluoride luminescence in acidic aqueous solutions  

SciTech Connect (OSTI)

Luminescence emission spectra and decay rates are reported for uranyl species in acidic aqueous solutions containing HF or added NaF. The longest luminescence lifetime, 0.269 {+-} 0.006 ms, was observed from uranyl in 1 M HF + 1 M HClO{sub 4} at 296 K and decreased with increasing temperature. Based on a luminescence dynamics model that assumes equilibrium among electronically excited uranyl fluoride species and free fluoride ion, this long lived uranyl luminescence in aqueous solution is attributed primarily to UO{sub 2}F{sub 2}. Studies on the effect of added LiNO{sub 3} or Na{sub 2}WO{sub 4}{center_dot}2H{sub 2}O showed relatively weak quenching of uranyl fluoride luminescence which suggests that high sensitivity determination of the UF{sub 6} content of WF{sub 6} gas should be feasible via uranyl luminescence analysis of hydrolyzed gas samples of impure WF{sub 6}.

Beitz, J.V.; Williams, C.W. [Argonne National Lab., IL (United States). Chemistry Div.

1996-08-01T23:59:59.000Z

17

Determination of the chemistry of HF acidizing with the use of {sup 19}F NMR spectroscopy  

SciTech Connect (OSTI)

A more thorough understanding of the chemistry of HF acid and its reaction products on silica and alumino-silicates is essential to the design and optimization of HF acidizing treatments. To more clearly define the chemistry of HF acidizing, an in-depth investigation of the reaction of HF and H{sub 2}SiF{sub 6} with alumino-silicates was undertaken using {sup 19}F Nuclear Magnetic Resonance (NMR) spectroscopy. In addition to the fluosilicic acid (H{sub 2}SiF{sub 6}) and AlF{sup 2+} predicted by traditional theories, {sup 19}F NMR spectroscopy shows a complex mixture of silicon and aluminum fluoride species in reacted HF acidizing solutions. During a secondary reaction of silicon fluorides with alumino-silicates, a constant F/Al ratio was maintained until the silicon fluorides had reacted completely. The distribution of the fluoride species depends on the HCl concentration. In this investigation, a tertiary reaction of HF acid on alumino-silicates was identified. When the silicon fluorides have reacted completely to give silica gel, the aluminum fluoride complexes continue to react on fresh alumino-silicates. The reaction causes the aluminum content to increase and the F/Al ratio and acid concentration to decrease. The final F/Al ratio is dependent upon acid strength and temperature. Numerous HF acidizing well returns have been analyzed to verify the reactions conducted in the laboratory. The extent of the reaction of HF acid can be determined with the use of {sup 19}F NMR spectroscopy. In wells with temperatures of 150 to 200 F, the reaction of H{sub 2}SiF{sub 6} is complete. Silicon content was quite low, and pH levels were 2 to 3. The F/Al ratios of the returns were 0.5 to 1.3, depending on the concentration of HCl and HF used in the treatment. In wells less than 100 F, the secondary reaction did not go to completion. Silicon and aluminum fluoride complexes were present in the returns along with live HCl.

Shuchart, C.E.; Buster, D.C.

1995-11-01T23:59:59.000Z

18

Calculated structures and fluoride affinities for fluorides  

SciTech Connect (OSTI)

It is shown that SCF-MO calculations provide good estimates of the energies of the processes MF/sub n/ ..-->.. M/sup n+/ + nF/sup -/ where M/sup n+/ is an ion of a first- or second-row element in a closed-shell or s/sup 2/ configuration. The fluoride ion affinities are then calculated for a number of molecules and ions. Where comparison with experiment is possible, the agreement is generally good when allowance is made for experimental uncertainties. In favorable cases, accurate heats of formation may be calculated from fluoride affinities.

O'Keeffe, M.

1986-07-23T23:59:59.000Z

19

Fluorination of amorphous thin-film materials with xenon fluoride  

DOE Patents [OSTI]

A method is disclosed for producing fluorine-containing amorphous semiconductor material, preferably comprising amorphous silicon. The method includes depositing amorphous thin-film material onto a substrate while introducing xenon fluoride during the film deposition process.

Weil, R.B.

1987-05-01T23:59:59.000Z

20

Nitrogen Trifluoride-Based Fluoride- Volatility Separations Process: Initial Studies  

SciTech Connect (OSTI)

This document describes the results of our investigations on the potential use of nitrogen trifluoride as the fluorinating and oxidizing agent in fluoride volatility-based used nuclear fuel reprocessing. The conceptual process uses differences in reaction temperatures between nitrogen trifluoride and fuel constituents that produce volatile fluorides to achieve separations and recover valuable constituents. We provide results from our thermodynamic evaluations, thermo-analytical experiments, kinetic models, and provide a preliminary process flowsheet. The evaluations found that nitrogen trifluoride can effectively produce volatile fluorides at different temperatures dependent on the fuel constituent.

McNamara, Bruce K.; Scheele, Randall D.; Casella, Andrew M.; Kozelisky, Anne E.

2011-09-28T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Development and demonstration of a personal monitoring system for exposure to hydrogen fluoride. Final report  

SciTech Connect (OSTI)

A good, functional Hydrogen Fluoride Gasbadge dosimeter has been developed for sampling of airborne HF vapor. The device is small (7.7 cm {times} 5.4 cm {times} 1.9 cm) and can easily and conveniently be worn on one`s lapel. It consists of polyethylene and polypropylene parts and a triethanolamine-impregnated polyproylene collection element. It is completely self contained, requiring no pumps, impingers, or sampling tubes. Subsequent to sampling, the collection element is analyzed quickly and easily with a fluoride selective-ion electrode. Laboratory tests were conducted to determine precision, linearity, interference effects, influences of temperature and humidity, and collection element stability over time. Results of the tests indicate that the Abcor Gasbadge HF dosimeter is an excellent passive HF monitor for work spaces, and that results obtained with it are accurate within {plus_minus}25%. These results have been corroborated in a field study.

Young, M.S.; Monat, J.P.

1993-09-01T23:59:59.000Z

22

Thermodynamics of the conversion of calcium and magnesium fluorides to the parent metal oxides and hydrogen fluoride  

SciTech Connect (OSTI)

The authors have used thermodynamic modeling to examine the reaction of calcium fluoride (CaF{sub 2}) and magnesium fluoride (MgF{sub 2}) with water (H{sub 2}O) at elevated temperatures. The calculated, equilibrium composition corresponds to the global free-energy minimum for the system. Optimum, predicted reaction temperatures and reactant mole ratios are reported for the recovery of hydrogen fluoride (HF), a valuable industrial feedstock. Complete conversion of MgF{sub 2} is found at 1,000 C and a ratio of 40 moles of H{sub 2}O per 1 mole of MgF{sub 2}. For CaF{sub 2}, temperatures as high as 1,400 C are required for complete conversion at a corresponding mole ratio of 40 moles of H{sub 2}O per 1 mole of CaF{sub 2}. The authors discuss the presence of minor chemical constituents as well as the stability of various potential container materials for the pyrohydrolysis reactions at elevated temperatures. CaF{sub 2} and MgF{sub 2} slags are available as wastes at former uranium production facilities within the Department of Energy Complex and other facilities regulated by the Nuclear Regulatory Commission. Recovery of HF from these wastes is an example of environmental remediation at such facilities.

West, M.H.; Axler, K.M.

1997-02-01T23:59:59.000Z

23

Spectrophotometric determination of hydrogen peroxide in the presence of fluoride  

SciTech Connect (OSTI)

A simple, rapid method was required for the determination of 0.01 - 0.1M hydrogen peroxide in the presence of 10M HF and in solutions resulting from the dissolution of unirradiated nuclear fuel elements in this dissolvent. Fluoride is a serious interference in the classical spectrophotometric procedure for determining hydrogen peroxide as the yellow-colored Ti(IV)-peroxide complex. It was thought that this interference could be minimized by the addition of a fluoride-complexing metal ion. Zirconium, aluminum, and boron were studied at various metal ion to fluoride mole ratios to determine the optimum conditions for reducing the interference by fluoride when present at the 0.015M and 0.15M levels. All three were effective in reducing the interference, but only at a metal ion to fluoride ratio of one or greater. Although zirconium was the most effective complexer studied, an excess of ZR(IV) decreased the absorbance of the Ti(IV)-peroxide complex. Since excess aluminum does not interfere, a procedure was developed in which two moles of AI(III) are added for each mole of fluoride in the sample aliquot. The color develops rapidly at room temperature and is stable for at least 24 hours. The absorbance is linear over the range 1 {times} 10{sup {minus}4}M to 1.8 {times} 10-{sup {minus}3}M H{sub 2}O{sub 2} when measured in 1-cm cuvettes. The method tolerates a variety of metal ions and complexing agents at the 0.02M level.

Delmastro, J.R.

1991-07-08T23:59:59.000Z

24

Hf-irJ  

Office of Legacy Management (LM)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment ofofOxford SiteToledo SiteTonawanda North - ConsequencesDGwen Hf-irJ

25

Method for the recovery of fluorides from spent aluminum potlining and the production of an environmentally safe waste residue  

SciTech Connect (OSTI)

A method for recovery of fluoride values from spent potlining and fluoride containing insulating materials associated with the potlining is disclosed. Spent potlining and the insulating matericals are reduced to a fine particle size and incinerated. The ash residue is leached with a dilute caustic and the leachate is treated with a calcium compound to precipitate calcium fluoride. The calcium fluoride is dried to a moisture content of less than 0.1 percent and is treated with about 93 to 99 percent concentration of sulfuric acid to produce hydrogen fluoride gas and a metal sulfate. The hydrogen fluoride gas is fed into an alumina dry scrubber to produce alumina with absorbed fluorides to be used as feed material to reduction cells used in the manufacture of aluminum by electrolytic reduction. The metal sulfate residue is treated with lime and constitutes an environmentally safe product which can be disposed of as landfill material.

Snodgrass, J.B.; Cambridge, E.L.

1984-04-24T23:59:59.000Z

26

Influence of uranium on corrosion of stainless steel in solutions of fluoride in nitric acid  

SciTech Connect (OSTI)

Stainless steels corrode rapidly in solutions of fluoride in nitric acid; the higher the fluoride ion content, the more intense is the corrosion. The activating effect of the fluoride ions mainly reduces to dissolution of the oxide films. Small amounts somewhat retard the cathodic reduction of HNO/sub 3/. In this report the authors provide the results of an investigation of the influence of uranium ions on the corrosion-electrochemical behavior of stainless steel 12Kh18N10T in solutions of up to 10 moles/liter of HNO/sub 3/, with fluoride ions up to 0.1 mole/liter. The authors conclude that the retardation of corrosion of stainless steel by uranium, zirconium and aluminum ions in solutions of fluorides in nitric acid is mainly due to the formation of strong complexes of these metals with fluorine ions, leading to a reduction of the number of free HF molecules in the solution. The stronger the complex of metal with fluorine, the higher the corrosion resistance of the stainless steel in a solution of fluoride in nitric acid.

Kurtenov, M.M.

1985-09-01T23:59:59.000Z

27

Determination of Stability Constants of Hydrogen and Aluminum Fluorides with a Fluoride-Selective Electrode  

SciTech Connect (OSTI)

The ability to directly determine free fluoride ion concentration (or mean activity) simplifies gathering and interpretation of experimental data for studies of metal complexes. In this work, the new lanthanum fluoride electrode was used to measure free fluoride ion in an investigation of the hydrogen-fluoride and aluminum-fluoride systems in NH4NO3.

Baumann, E.W.

2003-01-06T23:59:59.000Z

28

Vapor-liquid equilibria for the systems difluoromethane + hydrogen fluoride, dichlorodifluoromethane + hydrogen fluoride, and chlorine + hydrogen fluoride  

SciTech Connect (OSTI)

Isothermal vapor-liquid equilibria for difluoromethane + hydrogen fluoride, dichlorodifluoromethane + hydrogen fluoride, and chlorine + hydrogen fluoride have been measured. The experimental data for the binary systems are correlated with the NRTL equation with the vapor-phase association model for the mixtures containing hydrogen fluoride, and the relevant parameters are presented. The binary system difluoromethane + hydrogen fluoride forms a homogeneous liquid phase, and the others form minimum boiling heterogeneous azeotropes at the experimental conditions.

Kang, Y.W. [KIST, Seoul (Korea, Republic of). Div. of Environmental and CFC Technology] [KIST, Seoul (Korea, Republic of). Div. of Environmental and CFC Technology

1998-01-01T23:59:59.000Z

29

Reduced-temperature processing and consolidation of ultra-refractory Ta4HfC5  

SciTech Connect (OSTI)

TaC, HfC, and WC powders were subjected to high-energy milling and hot pressing to produce Ta4HfC5, a composite of Ta(4)HfC5 + 30 vol.% WC, and a composite of Ta4HfC5 + 50 vol.% WC. Sub-micron powders were examined after four different milling intervals prior to hot pressing. XRD was used to verify proper phase formation. SEM, relative density, and hardness measurements were used to examine the resulting phases. Hot pressed compacts of Ta4HfC5 showed densification as high as 98.6% along with Vickers hardness values of 21.4 GPa. Similarly, Ta4HfC5 + 30 vol.% WC exhibited 99% densification with a Vickers hardness of 22.5 GPa. These levels of densification were achieved at 1500 degrees C, which is lower than any previously reported sintering temperature for Ta4HfC5. Microhardness values measured in this study were higher than those previously reported for Ta4HfC5. The WC additions to Ta4HfC5 were found to improve densification and increase microhardness. (C) 2013 Elsevier Ltd. All rights reserved.

Gaballa, Osama [Ames Laboratory; Cook, B. A. [TRI International; Russell, A. M. [Ames Laboratory

2013-04-26T23:59:59.000Z

30

Phase selection and transition in Hf-rich hafnia-titania nanolaminates  

SciTech Connect (OSTI)

Hf-rich hafnia-titania nanolaminate films with five HfO{sub 2}-TiO{sub 2} bilayer architectures (0.64 to 0.94 Hf atom fraction) were sputter deposited on unheated fused silica substrates, annealed post-deposition from 573 to 1273 K, and analyzed by x-ray diffraction to study phase selection and transition. Isochronal annealing for 1 h intervals from 573 to 1173 K produces weak crystallization into monoclinic (m) HfO{sub 2} doped with Ti, i.e., m-Hf{sub 1-x}Ti{sub x}O{sub 2}. The amount of Ti incorporated into m-HfO{sub 2} depends upon both architecture and overall stoichiometry, but in all but the coarsest architecture, exceeds the bulk solubility limit of x = 0.05. Initial annealing at 1273 K produces significant crystallization into a biphasic structure, m-Hf{sub 1-x}Ti{sub x}O{sub 2} and orthorhombic (o) HfTiO{sub 4}. From bulk phase equilibrium considerations, o-HfTiO{sub 4} is expected to crystallize under conditions of interfacial bilayer mixing. However, upon further annealing at 1273 K, o-HfTiO{sub 4} proves to be unstable. o-HfTiO{sub 4} demixing inevitably occurs independent of architecture and stoichiometry, resulting in final crystallization products after 96 h at 1273 K that are m-Hf{sub 1-x}Ti{sub x}O{sub 2} with x {approx_equal} 0.05 and TiO{sub 2} doped with Hf. We suggest that o-HfTiO{sub 4} instability arises from a driving force to form domains similar to those found in the low temperature in/commensurate structures of ZrTiO{sub 4}. A detailed crystallographic group-subgroup analysis of the o (Pbcn) {yields} m (P2{sub 1}/c) transition shows that these domains can be represented by an orientation twin in the latter structure and their creation can be achieved by a single step second-order phase transition.

Cisneros-Morales, Massiel Cristina; Rubin Aita, Carolyn

2011-06-15T23:59:59.000Z

31

The synthesis, characterization and reactivity of high oxidation state nickel fluorides  

SciTech Connect (OSTI)

The research described in this thesis has mainly addressed the challenge of the synthesis of thermodynamically unstable nickel fluorides, which cannot be made by traditional thermal methods. A low-temperature approach towards the synthesis of such transition metal fluorides exploits the greater thermodynamic stability of high oxidation states in anions and involves the use of anhydrous hydrogen fluoride (aHF) as a solvent. The general method consists of combining an aHF soluble starting material (e.g., K{sub 2}NiF{sub 6}) with a Lewis fluoroacid (e.g., BF{sub 3}), which precipitates a neutral polymeric solid state fluoride: 2 K{sup +} + NiF{sub 6}{sup 2{minus}} + BF{sub 3} {r_arrow} NiF{sub 4} + 2 BF{sub 4}{sup {minus}} + 2 K{sup +}. At room temperature, this reaction yields a different structural phase, with composition K{sub x}NiF{sub 3} (x {approx} 0.18). This material has a pseudo-hexagonal tungsten bronze structure (H{sub 0}-K{sub x}NiF{sub 3}), and is an ionic conductor, probably due to K{sup +} ions hosted in the lattice channels. R-NiF{sub 3} is capable of fluorinating a wide range of inorganic and organic substrates. These reactions have probably shed light on the mechanism of the Simons Electrochemical Fluorination (ECF) Process, an important industrial method of fluorinating organic compounds. It has long been speculated that NiF{sub 3} plays a role in the ECF process, which uses nickel electrodes in aHF solvent. K{sub 2}NiF{sub 6} also fluorinates organic compounds in aHF, but interestingly, yields different fluorinated products. The reduction of R-NiF{sub 3} and K{sub 2}NiF{sub 6} during fluorination reactions yields NiF{sub 2}. A method has been developed to regenerate NiF{sub 6}{sup 2{minus}} from NiF{sub 2}.

Chacon, L.C. [Univ. of Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley National Lab., CA (United States). Chemical Sciences Div.

1997-12-01T23:59:59.000Z

32

Ge interactions on HfO{sub 2} surfaces and kinetically driven patterning of Ge nanocrystals on HfO{sub 2}  

SciTech Connect (OSTI)

Germanium interactions are studied on HfO{sub 2} surfaces, which are prepared through physical vapor deposition (PVD) and by atomic layer deposition. X-ray photoelectron spectroscopy and temperature-programed desorption are used to follow the reactions of germanium on HfO{sub 2}. Germanium chemical vapor deposition at 870 K on HfO{sub 2} produces a GeO{sub x} adhesion layer, followed by growth of semiconducting Ge{sup 0}. PVD of 0.7 ML Ge (accomplished by thermally cracking GeH{sub 4} over a hot filament) also produces an initial GeO{sub x} layer, which is stable up to 800 K. PVD above 2.0 ML deposits semiconducting Ge{sup 0}. Temperature programed desorption experiments of {approx}1.0 ML Ge from HfO{sub 2} at 400-1100 K show GeH{sub 4} desorption below 600 K and GeO desorption above 850 K. These results are compared to Ge on SiO{sub 2} where GeO desorption is seen at 550 K. Exploiting the different reactivity of Ge on HfO{sub 2} and SiO{sub 2} allows a kinetically driven patterning scheme for high-density Ge nanoparticle growth on HfO{sub 2} surfaces that is demonstrated.

Stanley, Scott K.; Joshi, Sachin V.; Banerjee, Sanjay K.; Ekerdt, John G. [Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712-0231 (United States); Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, Texas 78712-0240 (United States); Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712-0231 (United States)

2006-01-15T23:59:59.000Z

33

Fluoride removal from water with spent catalyst  

SciTech Connect (OSTI)

The adsorption of fluoride from water with spent catalyst was studied. Adsorption density of fluoride decreased with increasing pH. Linear adsorption isotherm was utilized to describe the adsorption reaction. The adsorption was a first-order reaction, and the rate constant increased with decreasing surface loading. Adsorption reaction of fluoride onto spent catalyst was endothermic, and the reaction rate increased slightly with increasing temperature. Fluoro-alumino complex and free fluoride ion were involved in the adsorption reaction. It is proposed that both the silica and alumina fractions of spent catalyst contribute to the removal of fluoride from aqueous solution. Coulombic interaction is proposed as the major driving force of the adsorption reaction of fluoride onto spent catalyst.

Lai, Y.D.; Liu, J.C. [National Taiwan Institute of Technology, Taipei (Taiwan, Province of China)

1996-12-01T23:59:59.000Z

34

PREPARATION OF ANHYDROUS F-18 FLUORIDE, T. Tewson. Journal of Labelled Compounds and Radiopharmaceuticals S165; 52, Supplement 1 2009  

SciTech Connect (OSTI)

The original specific aims of the grant where cut back considerably as the study section reduced both the time and the budget for the project. The objective of the grant was to show that fluorine-18 fluoride could be prepared completely anhydrous and thus substantially more reactive than conventionally dried fluoride using the method of Sun and DiMagno. This method involved using conventionally dried fluoride to prepare an aromatic fluoride in which the aromatic ring is substituted with electron withdrawing groups. The aryl fluoride is then dried and purified and the fluoride is displaced with an anhydrous nucleophile. Using fluorine-19 and macroscopic scale reactions the reactions work well and give anhydrous fluoride salts that are both more reactive and more selective in their reactions than conventionally dried fluoride. The original substrate chosen for the reaction was bromopentacyanobenzene (1). This compound proved to be easy to make but very hard to purify. As an alternative hexabromobenzene, which is commercially available in high purity, was tried. This reacted cleanly with conventionally dried F-18 fluoride in acetonitrile to give [{sup 18}F]-fluoropentabromobenzene (2), which could be dried by passage of the solution over alumina, which also removed any unreacted fluoride. The fluorine-18 fluoride could be liberated from (2) by displacement with an anhydrous nucleophilic tetra-alkylammonium salt but the anion had to be chosen with considerable care. The reaction is potentially reversible especially as, on the no carrier added scale, there is inevitably an excess of hexabromobenzene and so the displacing nucleophile is chosen to deactivate the aromatic compound to further nucleophilic displacement reactions. To this end tetrabutylammonium azide and tetrabutylammonium phenolate have been tried. Both work but the phenolate is probably the better choice. The F-18 fluoride produced by this process is substantially more reactive than conventionally dried fluoride. A solution of the 3'-anhydrothymidine-5-benzoate (3) was added to the fluoride solution and 30% of the fluoride was incorporated in less than 3 minutes at room temperature were as conventionally dried fluoride requires 10 minutes at 160 C and gives {approx}10% incorporation. These results are encouraging in that they show that the objective of truly anhydrous fluoride is worth pursuing but the problem is that you end up with too much 'stuff' in the solution. Four to five milligrams of hexabromobenzene are used for the initial fluorination reaction and enough of the tetra-alkylammonium salt has to be added to react with a substantial number of those bromides. No attempt has been made to optimize these amounts but there is clearly a lot of material in the solution before the final substrate is added. To avoid these difficulties experiments involving a different, low boiling carrier of the fluoride which can be distilled from the initial fluorination mixture have been tried. Phenyltrifluoromethane sulfonate reacts with fluoride to give trifluoromethane sulfonyl fluoride which boils at -20 C as shown. This reaction works with conventionally dried fluorine-18 fluoride and the no carrier added trifluoromethane sulphonyl fluoride distills out of the reaction as it forms. The choice of nucleophile to react it with to liberate the fluoride is limited and the obvious choice is tetrabutylammonium azide as the resulting trifluoromethane sulfonyl azide is unreactive. We have shown that this works in principle but the experimental details have not been explored.

Tewson, T.

2009-07-01T23:59:59.000Z

35

Process for the production of high purity zirconium tetrafluoride and other fluorides  

SciTech Connect (OSTI)

This patent describes a process for producing metal fluorides for low optical loss glass applications selected from the group. It comprises: aluminum trifluoride, hafnium tetrafluoride and zirconium tetrafluoride. The steps comprise: incompletely reacting reactants of a fluorinating agent selected from the group consisting of F{sub 2}, NF{sub 3}, N{sub 2}F{sub 2}, N{sub 2}F{sub 4}, ClF{sub 3}, BrF{sub 3}, IF{sub 5} and SF{sub 4} and a metal selected from the group consisting of aluminum, hafnium and zirconium, or the corresponding metal's compound to produce a reaction product comprising the metal fluoride and at least an amount of the residual metal or its compound effective to react with any metal fluoride impurities in the reactants, and separating the metal fluoride from the reaction product by heating the reaction product to selectively vaporize the metal fluoride for separate recovery from the reaction product and to react the residual metal or its compound with the metal fluoride impurities.

Withers, H.P.; Woytek, A.J.; Lileck, J.T.

1991-01-08T23:59:59.000Z

36

Polyvinylidene Fluoride-Based Membranes for Direct Methanol Fuel...  

Broader source: Energy.gov (indexed) [DOE]

Polyvinylidene Fluoride-Based Membranes for Direct Methanol Fuel Cell Applications Polyvinylidene Fluoride-Based Membranes for Direct Methanol Fuel Cell Applications Presentation...

37

Current status of fluoride volatility method development  

SciTech Connect (OSTI)

The Fluoride Volatility Method is based on a separation process, which comes out from the specific property of uranium, neptunium and plutonium to form volatile hexafluorides whereas most of fission products (mainly lanthanides) and higher transplutonium elements (americium, curium) present in irradiated fuel form nonvolatile tri-fluorides. Fluoride Volatility Method itself is based on direct fluorination of the spent fuel, but before the fluorination step, the removal of cladding material and subsequent transformation of the fuel into a powdered form with a suitable grain size have to be done. The fluorination is made with fluorine gas in a flame fluorination reactor, where the volatile fluorides (mostly UF{sub 6}) are separated from the non-volatile ones (trivalent minor actinides and majority of fission products). The subsequent operations necessary for partitioning of volatile fluorides are the condensation and evaporation of volatile fluorides, the thermal decomposition of PuF{sub 6} and the finally distillation and sorption used for the purification of uranium product. The Fluoride Volatility Method is considered to be a promising advanced pyrochemical reprocessing technology, which can mainly be used for the reprocessing of oxide spent fuels coming from future GEN IV fast reactors.

Uhlir, J.; Marecek, M.; Skarohlid, J. [UJV - Nuclear Research Institute, Research Centre Rez, CZ-250 68 Husinec - Rez 130 (Czech Republic)

2013-07-01T23:59:59.000Z

38

www.eurofluor.org CTEF Comit Technique Europen du Fluor Comit Technique Europen du Fluor  

E-Print Network [OSTI]

Fluor Working group Storage, Transportation and Safety Guidelines in case of a Hydrogen Fluoride of HF Exposure Page 2 of 20 pages PREFACE Hydrogen fluoride (HF) is essential for chemical industry and therefore, there is a need for HF to be produced, transported, stored and used. HF is primarily

Saskatchewan, University of

39

Sulfuryl fluoride in the global atmosphere  

E-Print Network [OSTI]

The first calibrated high-frequency, high-precision, in situ atmospheric and archived air measurements of the fumigant sulfuryl fluoride (SO[subscript 2]F[subscript 2]) have been made as part of the Advanced Global Atmospheric ...

Muhle, J.

40

Transition metal fluorides: from superconductors to multiferroics.   

E-Print Network [OSTI]

Transition metal fluorides represent an important family of complex solids displaying a variety of different properties and interesting phenomena. Despite their remarkable behaviour, these classes of materials have not ...

Drathen, Christina

2013-06-29T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Isothermal vapor-liquid equilibria for the systems 1-chloro-1,1-difluoroethane + hydrogen fluoride, 1,1-dichloro-1-fluoroethane + hydrogen fluoride, and chlorodifluoromethane + hydrogen fluoride  

SciTech Connect (OSTI)

Isothermal vapor-liquid equilibria for the three binary systems (1-chloro-1,1-difluoroethane + hydrogen fluoride, 1,1-dichloro-1-fluoroethane + hydrogen fluoride, and chlorodifluoromethane + hydrogen fluoride) have been measured. The experimental data for the binary systems are correlated with the NRTL equation with the vapor-phase association model for the mixtures containing hydrogen fluoride, and the relevant parameters are presented. All of the systems form minimum boiling heterogeneous azeotropes.

Kang, Y.W.; Lee, Y.Y. [KIST, Seoul (Korea, Republic of)] [KIST, Seoul (Korea, Republic of)

1997-03-01T23:59:59.000Z

42

Method for fluorination of actinide fluorides and oxyfluorides using O/sub 2/F/sub 2/  

DOE Patents [OSTI]

The present invention relates generally to methods of fluorination and more particularly to the use of O/sub 2/F/sub 2/ for the preparation of actinide hexafluorides, and for the extraction of deposited actinides and fluorides and oxyfluorides thereof from reaction vessels. The experiments set forth hereinabove demonstrate that the room temperature or below use of O/sub 2/F/sub 2/ will be highly beneficial for the preparation of pure actinide hexafluorides from their respective tetrafluorides without traces of HF being present as occurs using other fluorinating agents: and decontamination of equipment previously exposed to actinides: e.g., walls, feed lines, etc.

Eller, P.G.; Malm, J.G.; Penneman, R.A.

1984-08-01T23:59:59.000Z

43

Interfacial reaction induced phase separation in La{sub x}Hf{sub y}O films  

SciTech Connect (OSTI)

Amorphous La{sub x}Hf{sub y}O films containing La at concentrations (x) of 50 and 20% were prepared by atomic layer deposition on ultrathin SiO{sub 2} films (1 nm). We examined the electronic structures and microstructures of the La{sub x}Hf{sub y}O films by x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDS), and x-ray diffraction (XRD). Phase separation into La{sub 2}O{sub 3} and HfO{sub 2} was observed in the La{sub x}Hf{sub y}O films subjected to annealing temperatures over 900 deg. C, although the mixture of La{sub 2}O{sub 3} and HfO{sub 2} is thermodynamically stable. The structural changes that occurred as the result of phase separation were dependent on the concentrations of La and Hf in the films. During the annealing treatment, silicate was produced due to interfacial reactions and the interfacial reactions were found to be dependent on the La{sub 2}O{sub 3} content in the La{sub x}Hf{sub y}O films, which has a significant influence on the phase separation process and resulting film structure.

Ma, J. W.; Lee, W. J.; Cho, M.-H. [Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 (Korea, Republic of); Lee, K. M.; Sohn, H. C. [Department of Material Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, C. S. [Korea Research Institute of Standards and Science, Daejeon 305-540 (Korea, Republic of); Cho, H. J. [Process Development Team, Semiconductor R and D Center, Samsung Electronics Co., LTD, Gyeonggi-Do 449-711 (Korea, Republic of)

2011-06-15T23:59:59.000Z

44

Method for removing fluoride contamination from nitric acid  

SciTech Connect (OSTI)

Fluoride ions are removed from nitric acid solution by contacting the vaporized solution with alumina or zirconium.

Howerton, W.B.; Pruett, D.J.

1982-07-13T23:59:59.000Z

45

Selective Adsorption of Sodium Aluminum Fluoride Salts from Molten Aluminum  

SciTech Connect (OSTI)

Aluminum is produced in electrolytic reduction cells where alumina feedstock is dissolved in molten cryolite (sodium aluminum fluoride) along with aluminum and calcium fluorides. The dissolved alumina is then reduced by electrolysis and the molten aluminum separates to the bottom of the cell. The reduction cell is periodically tapped to remove the molten aluminum. During the tapping process, some of the molten electrolyte (commonly referred as “bath” in the aluminum industry) is carried over with the molten aluminum and into the transfer crucible. The carryover of molten bath into the holding furnace can create significant operational problems in aluminum cast houses. Bath carryover can result in several problems. The most troublesome problem is sodium and calcium pickup in magnesium-bearing alloys. Magnesium alloying additions can result in Mg-Na and Mg-Ca exchange reactions with the molten bath, which results in the undesirable pickup of elemental sodium and calcium. This final report presents the findings of a project to evaluate removal of molten bath using a new and novel micro-porous filter media. The theory of selective adsorption or removal is based on interfacial surface energy differences of molten aluminum and bath on the micro-porous filter structure. This report describes the theory of the selective adsorption-filtration process, the development of suitable micro-porous filter media, and the operational results obtained with a micro-porous bed filtration system. The micro-porous filter media was found to very effectively remove molten sodium aluminum fluoride bath by the selective adsorption-filtration mechanism.

Leonard S. Aubrey; Christine A. Boyle; Eddie M. Williams; David H. DeYoung; Dawid D. Smith; Feng Chi

2007-08-16T23:59:59.000Z

46

BAND STRUCTURE AND OPTICAL PROPERTIES OF MAGNESIUM FLUORIDE  

E-Print Network [OSTI]

595 BAND STRUCTURE AND OPTICAL PROPERTIES OF MAGNESIUM FLUORIDE C. JOUANIN, J. P. ALBERT and C'autres transitions expéri- mentales. Abstract. 2014 The electronic band structure of magnesium fluoride is calculated, only some qualitative investigations exist for the calcium and magnesium fluorides [1, 2]. This lack

Paris-Sud XI, Université de

47

Rare earth/iron fluoride and methods for making and using same  

DOE Patents [OSTI]

A particulate mixture of Fe.sub.2 O.sub.3 and RE.sub.2 O.sub.3, where RE is a rare earth element, is reacted with an excess of HF acid to form an insoluble fluoride compound (salt) comprising REF.sub.3 and FeF.sub.3 present in solid solution in the REF.sub.3 crystal lattice. The REF.sub.3 /FeF.sub.3 compound is dried to render it usable as a reactant in the thermite reduction process as well as other processes which require an REF.sub.3 /FeF.sub.3 mixture. The dried REF.sub.3 /FeF.sub.3 compound comprises about 5 weight % to about 40 weight % of FeF.sub.3 and the balance REF.sub.3 to this end.

Schmidt, Frederick A. (Ames, IA); Wheelock, John T. (Neveda, IA); Peterson, David T. (Ames, IA)

1991-12-17T23:59:59.000Z

48

Acidizing of Sandstone Reservoirs Using HF and Organic Acids  

E-Print Network [OSTI]

Mud acid, which is composed of HCl and HF, is commonly used to remove the formation damage in sandstone reservoirs. However, many problems are associated with HCl, especially at high temperatures. Formic-HF acids have served as an alternative...

Yang, Fei

2012-10-19T23:59:59.000Z

49

Ternary ceramic alloys of Zr-Ce-Hf oxides  

DOE Patents [OSTI]

A ternary ceramic alloy is described which produces toughening of zirconia and zirconia composites through the stress transformation from tetragonal phase to monoclinic phase. This alloy, having the general formula Ce[sub x]Hf[sub y]Zr[sub 1[minus]x[minus]y]O[sub 2], is produced through the addition of appropriate amounts of ceria and hafnia to the zirconia. Typically, improved toughness is achieved with about 5 to about 15 mol % ceria and up to about 40 mol % hafnia. The preparation of alloys of these compositions are given together with data as to the densities, tetragonal phase content, hardness and fracture toughness. The alloys are useful in preparing zirconia bodies as well as reinforcing ceramic composites. 1 fig.

Becher, P.F.; Funkenbusch, E.F.

1990-11-20T23:59:59.000Z

50

Ternary ceramic alloys of ZR-CE-HF oxides  

DOE Patents [OSTI]

A ternary ceramic alloy which produces toughening of zirconia and zirconia composites through the stress transformation from tetragonal phase to monoclinic phase. This alloy, having the general formula Ce.sub.x Hf.sub.y Zn.sub.1-x-y O.sub.2, is produced through the addition of appropriate amounts of ceria and hafnia to the zirconia. Typically, improved toughness is achieved with about 5 to about 15 mol % ceria and up to about 40 mol % hafnia. The preparation of alloys of these compositions are given together with data as to the densities, tetragonal phase content, hardness and fracture toughness. The alloys are useful in preparing zirconia bodies as well as reinforcing ceramic composites.

Becher, Paul F. (Oak Ridge, TN); Funkenbusch, Eric F. (White Bear Lake, MN)

1990-01-01T23:59:59.000Z

51

Infrared study on room-temperature atomic layer deposition of HfO{sub 2} using tetrakis(ethylmethylamino)hafnium and remote plasma-excited oxidizing agents  

SciTech Connect (OSTI)

Room-temperature atomic layer deposition (ALD) of HfO{sub 2} was examined using tetrakis (ethylmethylamino)hafnium (TEMAH) and remote plasma-excited water and oxygen. A growth rate of 0.26?nm/cycle at room temperature was achieved, and the TEMAH adsorption and its oxidization on HfO{sub 2} were investigated by multiple internal reflection infrared absorption spectroscopy. It was observed that saturated adsorption of TEMAH occurs at exposures of ?1?×?10{sup 5}?L (1 L?=?1?×?10{sup ?6} Torr s) at room temperature, and the use of remote plasma-excited water and oxygen vapor is effective in oxidizing the TEMAH molecules on the HfO{sub 2} surface, to produce OH sites. The infrared study suggested that Hf–OH plays a role as an adsorption site for TEMAH. The reaction mechanism of room temperature HfO{sub 2} ALD is discussed in this paper.

Kanomata, Kensaku [Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa 992-8510, Japan and Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083 (Japan); Ohba, Hisashi; Pungboon Pansila, P.; Ahmmad, Bashir; Kubota, Shigeru; Hirahara, Kazuhiro; Hirose, Fumihiko, E-mail: fhirose@yz.yamagata-u.ac.jp [Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa 992-8510 (Japan)

2015-01-01T23:59:59.000Z

52

Synthesis, structure, and reactivity of high oxidation state silver fluorides and related compounds  

SciTech Connect (OSTI)

This thesis has been largely concerned with defining the oxidizing power of Ag(III) and Ag(II) in anhydrous hydrogen fluoride (aHF) solution. Emphasis was on cationic species, since in a cation the electronegativity of a given oxidation state is greatest. Cationic Ag(III) solv has a short half life at ordinary temperatures, oxidizing the solvent to elemental fluorine with formation of Ag(II). Salts of such a cation have not yet been preparable, but solutions which must contain such a species have proved to be effective and powerful oxidizers. In presence of PtF{sub 6}{sup {minus}}, RuF{sub 6}{sup {minus}}, or RhF{sub 6}{sup {minus}}, Ag(III) solv effectively oxidizes the anions to release the neutral hexafluorides. Such reactivity ranks cationic Ag(III) as the most powerfully oxidizing chemical agent known as far. Unlike its trivalent relative Ag (II) solv is thermodynamically stable in acid aHF. Nevertheless, it oxidizes IrF{sub 6}{sup {minus}} to IrF{sub 6} at room temperature, placing its oxidizing potential not more than 2 eV below that of cationic Ag(III). Range of Ag{sup 2+} (MF{sub 6}{sup {minus}}){sub 2} salts attainable in aHF has been explored. An anion must be stable with respect to electron loss to Ag{sup 2+}. The anion must also be a poor F{sup {minus}} donor; otherwise, either AgF{sup +} salts or AgF{sub 2} are generated.

Lucier, G.M.

1995-05-01T23:59:59.000Z

53

Digital hf radar observations of equatorial spread-F  

SciTech Connect (OSTI)

Modern digital ionosondes, with both direction finding and doppler capabilities can provide large scale pictures of the Spread-F irregularity regions. A morphological framework has been developed that allows interpretation of the hf radar data. A large scale irregularity structure is found to be nightward of the dusk terminator, stationary in the solar reference frame. As the plasma moves through this foehn-wall-like structure it descends, and irregularities may be generated. Localized upwellings, or bubbles, may be produced, and they drift with the background plasma. The spread-F irregularity region is found to be best characterized as a partly cloudy sky, due to the patchiness of the substructures. 13 references, 16 figures.

Argo, P.E.

1984-01-01T23:59:59.000Z

54

Chemical analysis of HfO{sub 2}/Si (100) film systems exposed to NH{sub 3} thermal processing  

SciTech Connect (OSTI)

Nitrogen incorporation in HfO{sub 2}/SiO{sub 2} films utilized as high-k gate dielectric layers in advanced metal-oxide-semiconductor field effect transistors has been investigated. Thin HfO{sub 2} blanket films deposited by atomic layer deposition on either SiO{sub 2} or NH{sub 3} treated Si (100) substrates have been subjected to NH{sub 3} and N{sub 2} anneal processing. Several high resolution techniques including electron microscopy with electron energy loss spectra, grazing incidence x-ray diffraction, and synchrotron x-ray photoelectron spectroscopy have been utilized to elucidate chemical composition and crystalline structure differences between samples annealed in NH{sub 3} and N{sub 2} ambients as a function of temperature. Depth profiling of core level binding energy spectra has been obtained by using variable kinetic energy x-ray photoelectron spectroscopy with tunable photon energy. An 'interface effect' characterized by a shift of the Si{sup 4+} feature to lower binding energy at the HfO{sub 2}/SiO{sub 2} interface has been detected in the Si 1s spectra; however, no corresponding chemical state change has been observed in the Hf 4f spectra acquired over a broad range of electron take-off angles and surface sensitivities. The Si 2p spectra indicate Si-N bond formation beneath the HfO{sub 2} layer in the samples exposed to NH{sub 3} anneal. The NH{sub 3} anneal ambient is shown to produce a metastable Hf-N bond component corresponding to temperature driven dissociation kinetics. These findings are consistent with elemental profiles across the HfO{sub 2}/Si(100) interface determined by electron energy loss spectroscopy measurements. X-ray diffraction measurements on similarly treated films identify the structural changes resulting from N incorporation into the HfO{sub 2} films.

Lysaght, Patrick S.; Barnett, Joel; Bersuker, Gennadi I.; Woicik, Joseph C.; Fischer, Daniel A.; Foran, Brendan; Tseng, Hsing-Huang; Jammy, Raj [Front End Process Division, SEMATECH, 2706 Montopolis Drive, Austin, Texas 78741-6499 (United States); National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Physical Characterization Laboratory, Advanced Technology Development Facility, 2706 Montopolis Drive, Austin, Texas 78741-6499 (United States); Front End Process Division, SEMATECH, 2706 Montopolis Drive, Austin, Texas 78741-6499 (United States)

2007-01-15T23:59:59.000Z

55

Aluminum fluoride inhibition of glucocorticoid receptor inactivation and transformation  

SciTech Connect (OSTI)

Fluoride, in the presence of aluminum ions, reversibly inhibits the temperature-mediated inactivation of unoccupied glucocorticoid receptors in cytosol preparations from mouse L cells. The effect is concentration-dependent, with virtually complete stabilization of specific glucocorticoid-binding capacity at 2 mM fluoride and 100 microM aluminum. These concentrations of aluminum and fluoride are ineffective when used separately. Aluminum fluoride also stabilizes receptors toward inactivation by gel filtration and ammonium sulfate precipitation. Aluminum fluoride prevents temperature-dependent transformation of steroid-receptor complexes to the DNA-binding state. Aluminum fluoride does not inhibit calf intestine alkaline phosphatase, and unoccupied receptors inactivated by this enzyme in the presence of aluminum fluoride can be completely reactivated by dithiothreitol. The effects of aluminum fluoride are due to stabilization of the complex between the glucocorticoid receptor and the 90-kDa mammalian heat-shock protein hsp90, which suggests that aluminum fluoride interacts directly with the receptor. Endogenous thermal inactivation of receptors in cytosol is not accompanied by receptor dephosphorylation. However, inactivation is correlated with dissociation of hsp90 from the unoccupied receptor. These results support the proposal that hsp90 is required for the receptor to bind steroid and dissociation of hsp90 is sufficient to inactivate the unoccupied receptor.

Housley, P.R. (Univ. of South Carolina School of Medicine, Columbia (USA))

1990-04-10T23:59:59.000Z

56

Examination of Liquid Fluoride Salt Heat Transfer  

SciTech Connect (OSTI)

The need for high efficiency power conversion and energy transport systems is increasing as world energy use continues to increase, petroleum supplies decrease, and global warming concerns become more prevalent. There are few heat transport fluids capable of operating above about 600oC that do not require operation at extremely high pressures. Liquid fluoride salts are an exception to that limitation. Fluoride salts have very high boiling points, can operate at high temperatures and low pressures and have very good heat transfer properties. They have been proposed as coolants for next generation fission reactor systems, as coolants for fusion reactor blankets, and as thermal storage media for solar power systems. In each case, these salts are used to either extract or deliver heat through heat exchange equipment, and in order to design this equipment, liquid salt heat transfer must be predicted. This paper discusses the heat transfer characteristics of liquid fluoride salts. Historically, heat transfer in fluoride salts has been assumed to be consistent with that of conventional fluids (air, water, etc.), and correlations used for predicting heat transfer performance of all fluoride salts have been the same or similar to those used for water conventional fluids an, water, etc). A review of existing liquid salt heat transfer data is presented, summarized, and evaluated on a consistent basis. Less than 10 experimental data sets have been found in the literature, with varying degrees of experimental detail and measured parameters provided. The data has been digitized and a limited database has been assembled and compared to existing heat transfer correlations. Results vary as well, with some data sets following traditional correlations; in others the comparisons are less conclusive. This is especially the case for less common salt/materials combinations, and suggests that additional heat transfer data may be needed when using specific salt eutectics in heat transfer equipment designs. All of the data discussed above were taken under forced convective conditions (both laminar and turbulent). Some recent data taken at ORNL under free convection conditions are also presented and results discussed. This data was taken using a simple crucible experiment with an instrumented nickel heater inserted in the salt to induce natural circulation within the crucible. The data was taken over a temperature range of 550oC to 650oC in FLiNaK salt. This data covers both laminar and turbulent natural convection conditions, and is compared to existing forms of natural circulation correlations.

Yoder Jr, Graydon L [ORNL] [ORNL

2014-01-01T23:59:59.000Z

57

Dispersion of UO{sub 2}F{sub 2} aerosol and HF vapor in the operating floor during winter ventilation at the Paducah Gaseous Diffusion Plant  

SciTech Connect (OSTI)

The gaseous diffusion process is currently employed at two plants in the US: the Paducah Gaseous Diffusion Plant and the Portsmouth Gaseous Diffusion Plant. As part of a facility-wide safety evaluation, a postulated design basis accident involving large line-rupture induced releases of uranium hexafluoride (UF{sub 6}) into the process building of a gaseous diffusion plant (GDP) is evaluated. When UF{sub 6} is released into the atmosphere, it undergoes an exothermic chemical reaction with moisture (H{sub 2}O) in the air to form vaporized hydrogen fluoride (HF) and aerosolized uranyl fluoride (UO{sub 2}F{sub 2}). These reactants disperse in the process building and transport through the building ventilation system. The ventilation system draws outside air into the process building, distributes it evenly throughout the building, and discharges it to the atmosphere at an elevated temperature. Since air is recirculated from the cell floor area to the operating floor, issues concerning in-building worker safety and evacuation need to be addressed. Therefore, the objective of this study is to evaluate the transport of HF vapor and UO{sub 2}F{sub 2} aerosols throughout the operating floor area following B-line break accident in the cell floor area.

Kim, S.H.; Chen, N.C.J.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W. [Oak Ridge National Lab., TN (United States); Carter, J.C. [J.C. Carter Associates, Inc., Knoxville, TN (United States)

1996-12-30T23:59:59.000Z

58

FLUORIDE ION COMPLEXATION BY STIBONIUM LEWIS ACIDSTOWARD APPLICATION IN BIOIMAGING  

E-Print Network [OSTI]

, these antimony species react with fluoride ions in organic solvents and sometimes in aqueous solutions to form the corresponding fluorostiboranes. Formation of these fluoride species can be conveniently monitored by a variety of techniques such as UV-vis and NMR...

Haile, Merid 1989-

2011-05-06T23:59:59.000Z

59

Scintillation of rare earth doped fluoride nanoparticles  

SciTech Connect (OSTI)

The scintillation response of rare earth (RE) doped core/undoped (multi-)shell fluoride nanoparticles was investigated under x-ray and alpha particle irradiation. A significant enhancement of the scintillation response was observed with increasing shells due: (i) to the passivation of surface quenching defects together with the activation of the REs on the surface of the core nanoparticle after the growth of a shell, and (ii) to the increase of the volume of the nanoparticles. These results are expected to reflect a general aspect of the scintillation process in nanoparticles, and to impact radiation sensing technologies that make use of nanoparticles.

Jacobsohn, L. G.; McPherson, C. L.; Sprinkle, K. B.; Ballato, J. [Center for Optical Materials Science and Engineering Technologies (COMSET), and School of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634 (United States); Yukihara, E. G. [Physics Department, Oklahoma State University, Stillwater, Oklahoma 74078-3072 (United States); DeVol, T. A. [Department of Environmental Engineering and Earth Sciences, Clemson University, Clemson, South Carolina 29634-0905 (United States)

2011-09-12T23:59:59.000Z

60

E-Print Network 3.0 - al hf ta Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

-based gate dielectric for MOSFETs with TaN metal gate. By incorporating Ta into HfO2 films, significant... shift than HfO2 3. In this work, we developed HfTaO gate ......

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

DEPARTMENT OF CHEMICAL ENGINEERING Name of SOP Manual Hydrofluoric Acid (HF) Etching of Glass  

E-Print Network [OSTI]

required Fume Hood, safety eye goggles, lab coat, two layers of nitrile gloves and HF Safety Kit Sequential containers. 5. HF is a glass etchant; only use plastic labware to contain HF. 6. Personal protective gear

Thompson, Michael

62

Hydrogen Fluoride Capture by Imidazolium Acetate Ionic Liquid  

E-Print Network [OSTI]

Extraction of hydrofluoric acid (HF) from oils is a drastically important problem in petroleum industry, since HF causes quick corrosion of pipe lines and brings severe health problems to humanity. Some ionic liquids (ILs) constitute promising scavenger agents thanks to strong binding to polar compounds and tunability. PM7-MD simulations and hybrid density functional theory are employed here to consider HF capture ability of ILs. Discussing the effects and impacts of the cation and the anion separately and together, I will evaluate performance of imidazolium acetate and outline systematic search guidelines for efficient adsorption and extraction of HF.

Chaban, Vitaly

2015-01-01T23:59:59.000Z

63

Hf propagation through actively modified ionospheres  

SciTech Connect (OSTI)

We have developed a computer modeling capability to predict the effect of localized electron density perturbations created by chemical releases or high-power radio frequency heating upon oblique, one-hop hf propagation paths. We have included 3-d deterministic descriptions of the depleted or enhanced ionization, including formation, evolution, and drift. We have developed a homing ray trace code to calculate the path of energy propagation through the modified ionosphere in order to predict multipath effects. We also consider the effect of random index of refraction variations using a formalism to calculate the mutual coherence functions for spatial and frequency separations based upon a path integral solution of the parabolic wave equation for a single refracted path through an ionosphere which contains random electron density fluctuations. 5 refs., 8 figs.

Argo, P.E.; Fitzgerald, T.J.; Wolcott, J.H.; Simons, D.J. (Los Alamos National Lab., NM (USA)); Warshaw, S.; Carlson, R. (Lawrence Livermore National Lab., CA (USA))

1990-01-01T23:59:59.000Z

64

Effect of aluminum fluoride on the physical properties and stability of fluorozirconate and fluorozirco-hafnate glasses  

SciTech Connect (OSTI)

The glass quality, physical properties, and thermal stability of fluorozirconate and fluorozirco-hafnate glasses were investigated as a function of the AIF{sub 3} content. The AIF{sub 3} concentration varied from 2 to 3.25 mol%. The ratio of the other components was constant, except for 50% substitution of ZrF{sub 4} by HfF{sub 4} in the fluorozirco-hafnate glasses. The physical properties of all the glasses were not affected strongly by AlF{sub 3} content. However, the fluorozirco-hafnate glasses were prone to precipitate out AlF{sub 3} microcrystals for AlF{sub 3} contents greater than 3 mol%. The thermal stability of the glasses revealed a compositional dependence only in the case of the fluorozirco-hafnate glasses. The thermal stability decreased as the AlF{sub 3} content increased above 3 mol%. The authors conclude that the AlF{sub 3} microcrystals nucleated other fluoride phases such as zirconium-barium fluoride crystals.

Busse, L.; Aggarwal, I. (Naval Research Lab., Washington, DC (US)); Sanghera, J.S. (Geo-centers Inc., Ft. Washington, MD (US)); Hart, P.; Sachon, M.G. (Sachs/Freeman Associates, Inc., Landover, MD (US))

1990-09-01T23:59:59.000Z

65

Effects of fluoride emissions on enzyme activity in metabolism of agricultural plants  

SciTech Connect (OSTI)

The effects of fluoride on the activity of malatedehydrogenase (MDH) in rape seed and rye grass have been investigated. Fluoride, which has been absorbed from the air, seems to act differently from fluoride added to the soil. The action of airborne fluoride compounds resorbed by the plant on the activity of MDH significantly correlated with the distance from an aluminum plant, crop yield, and fluoride content. 5 references, 5 figures, 2 tables.

Moeri, P.B.

1980-01-01T23:59:59.000Z

66

Large area electron beam pumped krypton fluoride laser amplifier  

SciTech Connect (OSTI)

Nike is a recently completed multi-kilojoule krypton fluoride (KrF) laser that has been built to study the physics of direct drive inertial confinement fusion. This paper describes in detail both the pulsed power and optical performance of the largest amplifier in the Nike laser, the 60 cm amplifier. This is a double pass, double sided, electron beam-pumped system that amplifies the laser beam from an input of 50 J to an output of up to 5 kJ. It has an optical aperture of 60 cm {times} 60 cm and a gain length of 200 cm. The two electron beams are 60 cm high {times} 200 cm wide, have a voltage of 640 kV, a current of 540 kA, and a flat top power pulse duration of 250 ns. A 2 kG magnetic field is used to guide the beams and prevent self-pinching. Each electron beam is produced by its own Marx/pulse forming line system. The amplifier has been fully integrated into the Nike system and is used on a daily basis for laser-target experiments. {copyright} {ital 1997 American Institute of Physics.}

Sethian, J.D.; Obenschain, S.P.; Gerber, K.A.; Pawley, C.J.; Serlin, V.; Sullivan, C.A. [Plasma Physics Division, Naval Research Laboratory, Washington DC 20375 (United States)] [Plasma Physics Division, Naval Research Laboratory, Washington DC 20375 (United States); Webster, W. [Research Support Instruments, 4325-B Forbes Boulevard, Lanham, Maryland 20706 (United States)] [Research Support Instruments, 4325-B Forbes Boulevard, Lanham, Maryland 20706 (United States); Deniz, A.V.; Lehecka, T. [Science Applications International Corporation, 1710 Goodridge Drive, McLean, Virginia 22102 (United States)] [Science Applications International Corporation, 1710 Goodridge Drive, McLean, Virginia 22102 (United States); McGeoch, M.W. [PLEX Corporation, 21 Addington Road, Brookline, Massachusetts 02146 (United States)] [PLEX Corporation, 21 Addington Road, Brookline, Massachusetts 02146 (United States); Altes, R.A.; Corcoran, P.A.; Smith, I.D. [Pulse Sciences, Incorporated, 600 McCormick Street, San Leandro, California 94577 (United States)] [Pulse Sciences, Incorporated, 600 McCormick Street, San Leandro, California 94577 (United States); Barr, O.C. [Pharos Technical Enterprises, 1603 Barcelona Street, Livermore, California 94550 (United States)] [Pharos Technical Enterprises, 1603 Barcelona Street, Livermore, California 94550 (United States)

1997-06-01T23:59:59.000Z

67

Characterization of double walled carbon nanotubes-polyvinylidene fluoride nanocomposites  

E-Print Network [OSTI]

One of the main objectives of this thesis is to disperse double-walled carbon nanotubes (DWNT) in a polyvinylidene fluoride (PVDF) matrix, and to characterize the resulting composite using electrical, thermal, and mechanical characterization...

Almasri, Atheer Mohammad

2007-04-25T23:59:59.000Z

68

ammonium fluoride precatalysts: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

sites can be seen in Figure 6-1. Of these sites, all are located within the United States. Fluorides are naturally-occurring components of rocks and soil and are also found in...

69

ammonium fluorides: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

sites can be seen in Figure 6-1. Of these sites, all are located within the United States. Fluorides are naturally-occurring components of rocks and soil and are also found in...

70

Amorphous powders of Al-Hf prepared by mechanical alloying  

SciTech Connect (OSTI)

We synthesized amorphous Al/sub 50/Hf/sub 50/ alloy powder by mechanically alloying an equimolar mixture of crystalline powders of Al and Hf using hexane as a dispersant. We characterized the powder as a function of mechanical-alloying time by scanning electron microscopy, x-ray diffraction, and differential scanning calorimetry. Amorphous Al/sub 50/Hf/sub 50/ powder heated at 10 K s/sup /minus/1/ crystallizes polymorphously at 1003 K into orthorhombic AlHf (CrB-type structure). During mechanical alloying, some hexane decomposes and hydrogen and carbon are incorporated into the amorphous alloy powder. The hydrogen can be removed by annealing the powder by hot pressing at a temperature approximately 30 K below the crystallization temperature. The amorphous compacts have a diamond pyramidal hardness of 1025 DPH. 24 refs., 7 figs., 1 tab.

Schwarz, R.B.; Hannigan, J.W.; Sheinberg, H.; Tiainen, T.

1988-01-01T23:59:59.000Z

71

Theoretical Assessment of 178m2Hf De-Excitation  

SciTech Connect (OSTI)

This document contains a comprehensive literature review in support of the theoretical assessment of the {sup 178m2}Hf de-excitation, as well as a rigorous description of controlled energy release from an isomeric nuclear state.

Hartouni, E P; Chen, M; Descalle, M A; Escher, J E; Loshak, A; Navratil, P; Ormand, W E; Pruet, J; Thompson, I J; Wang, T F

2008-10-06T23:59:59.000Z

72

Fluoride, aluminum, and phosphate kinetics in cryolite workers  

SciTech Connect (OSTI)

Exposure to cryolite (Na3AlF6) dust may result in skeletal fluorosis. Eight male workers at a cryolite concentrator participated in a 4-day study after 5 days of vacation. Dust exposures were 0.16 to 21.2 mg/m3. Urine was collected before work began and during two 4-hour periods. Preshift urine fluoride concentrations increased during the week. Fluoride concentrations in postshift urine and serum both correlated with the dust exposures. Serum fluoride concentrations decreased with a half-life of 3.3 to 6.9 hours after work. Fluoride clearance was 40.5 to 76.5 mL/min at urinary flow rates of 0.89 to 2.21 mL/min. Serum aluminum concentrations varied without relation to the exposure, but the urinary aluminum excretion correlated with the fluoride levels. Preshift serum-phosphate concentrations increased significantly during the week, possibly indicating changes in mineral metabolism. For monitoring of individual uptake of cryolite dust, serum fluoride measurements are most useful.

Grandjean, P.; Horder, M.; Thomassen, Y. (Odense Univ. (Denmark))

1990-01-01T23:59:59.000Z

73

Growth of HfO{sub 2} films using an alternate reaction of HfCl{sub 4} and O{sub 2} under atmospheric pressure  

SciTech Connect (OSTI)

HfO{sub 2} films were deposited onto a Si(100) substrate using an alternate reaction of HfCl{sub 4} and O{sub 2} under atmospheric pressure. Self-limiting growth of the HfO{sub 2} was achieved in the range of the growth temperature above 873K. The X-ray diffraction of the HfO{sub 2} films showed a typical diffraction pattern assigned to the monoclinic polycrystalline phase. Residual chloride concentration in HfO{sub 2} films were not higher than 0.1at%. When the growth temperature was 973K, the HfSiO{sub x} is formed in HfO{sub 2} film. This gives effective permittivity value of 9.6 for the HfO{sub 2} film grown at 573K.

Takahashi, Naoyuki [Department of Materials Science and Technology, Faculty of Engineering Shizuoka University, 3-5-1 Johoku, Hamamatu, Shizuoka 432-8561 (Japan)]. E-mail: tntakah@ipc.shizuoka.ac.jp; Nonobe, Shinichi [Department of Materials Science and Technology, Faculty of Engineering Shizuoka University, 3-5-1 Johoku, Hamamatu, Shizuoka 432-8561 (Japan); Nakamura, Takato [Department of Materials Science and Technology, Faculty of Engineering Shizuoka University, 3-5-1 Johoku, Hamamatu, Shizuoka 432-8561 (Japan)

2004-11-01T23:59:59.000Z

74

Growth mechanism difference of sputtered HfO{sub 2} on Ge and on Si  

SciTech Connect (OSTI)

HfO{sub 2} films were deposited by the reactive sputtering on Ge and Si substrates simultaneously, and we found both the interface layer and the HfO{sub 2} film were thinner on Ge substrate than those on Si substrate. A metallic Hf layer has a crucial role for the thickness differences of both interface layer and HfO{sub 2} film, since those thickness differences were observed only when an ultrathin metallic Hf layer was predeposited before the reactive sputtering process. The role of metallic Hf in these phenomena is understandable by assuming the formation of a volatile Hf-Ge-O ternary compound at the early stage of the film growth. This result shows that the HfO{sub 2}/Ge system has an advantage over the HfO{sub 2}/Si system from the viewpoint of further reduction of the gate oxide film thickness.

Kita, Koji; Kyuno, Kentaro; Toriumi, Akira [Department of Materials Science, School of Engineering, University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

2004-07-05T23:59:59.000Z

75

Removal of fluoride from aqueous solution by using alum sludge  

SciTech Connect (OSTI)

The ability of treated alum sludge to remove fluoride from aqueous solution has been investigated. The studies were carried out as functions of contact time, concentration of adsorbent and adsorbate, temperature, pH, and effect of concentrations of other anions. The data indicate that treated alum sludge surface sites are heterogeneous in nature and that fits into a heterogeneous site binding model. The optimum pH for complete removal of fluoride from aqueous solution was found to be 6. The rate of adsorption was rapid during the initial 5 minutes, and equilibrium was attained within 240 minutes. The adsorption followed first-order rate kinetics. The present system followed the Langmuir adsorption isotherm model. The loading factor (i.e., the milligram of fluoride adsorbed per gram of alum sludge) increased with initial fluoride concentration, whereas a negative trend was observed with increasing temperature. The influence of addition of anions on fluoride removal depends on the relative affinity of the anions for the surface and the relative concentrations of the anions.

Sujana, M.G.; Thakur, R.S.; Rao, S.B. [CSIR, Bhubaneswar (India). Regional Research Lab.] [CSIR, Bhubaneswar (India). Regional Research Lab.

1998-10-01T23:59:59.000Z

76

Lithium fluoride (LiF) crystal for parametric X-ray (PXR) production  

E-Print Network [OSTI]

Lithium fluoride (LiF) crystal for parametric X-ray (PXR) production B. Sones *, Y. Danon, R 2004 Abstract Parametric X-ray (PXR) production is reported using lithium fluoride (LiF) as a target

Danon, Yaron

77

First observation of /sup 162/Hf decay completion of an alpha -decay chain  

E-Print Network [OSTI]

The new isotope /sup 162/Hf (T/sub 1/2/=(37.6+or-0.8)s) is produced in a /sup 142/Nd (/sup 24/Mg,4n) reaction. The activities produced in this reaction are transported to a measuring station by use of a He- jet system. Decay properties are observed with alpha -, gamma -, and gamma - gamma -spectroscopy. The Z-assignment of the new isotope is based on a cross bombardment on /sup 141/Pr target and on the results of a gamma -X-ray coincidence measurement. The mass assignment is deduced from the excitation function measurements. From the measured alpha -decay energy E/sub alpha /=4308 (10) keV new mass values are derived for /sup 162/Hf, /sup 166/W, /sup 170/Os, /sup 174/Pt, and /sup 178/Hg. These new mass values make it possible to establish systematics of two-proton and one-proton binding energies far from stability. (20 refs).

Schrewe, U J; Hagberg, E; Hardy, J C; Koslowsky, V T; Schmeing, H; Sharma, K S

1981-01-01T23:59:59.000Z

78

Inhibition of the ATPase activity of Escherichia coli ATP synthase by magnesium fluoride  

E-Print Network [OSTI]

Inhibition of the ATPase activity of Escherichia coli ATP synthase by magnesium fluoride Zulfiqar activity of Escherichia coli ATP synthase by magnesium fluoride (MgFx) was studied. Wild-type F1-ATPase synthesis mechanism; Magnesium fluoride; ATPase inhibition; Transition state analog 1. Introduction ATP

Zulfiqar Ahmad

79

THE RAMAN SPECTRUM OF MAGNESIUM FLUORIDE By R. S. KRISHNAN and R. S. KATIYAR,  

E-Print Network [OSTI]

627. THE RAMAN SPECTRUM OF MAGNESIUM FLUORIDE By R. S. KRISHNAN and R. S. KATIYAR, Department, NOVEMBRE 1965, I Magnesium fluoride, which occurs in nature as the mineral sellaite, crystallizes spectrum of magnesium fluoride (MgF2) taken with a medium Quartz spectrograph. (b) Its microphotometer

Paris-Sud XI, Université de

80

Kinetics of the reactions of hydrogen fluoride with calcium oxide  

SciTech Connect (OSTI)

This paper studies the kinetics of interaction of gaseous hydrogen fluoride with calcium oxide at temperatures 300-700 degrees. The experiments were conducted in a laboratory adsorption apparatus modified and adapted for work with corrosive hydrogen fluoride. Calcium oxide samples in granulated form and deposited on gamma-alumina were used in the experiments. Kinetic curves representing variations of the degree of conversion of the solid samples with time are shown. The influence of retardation dure to diffusion was observed in the experiments. The influence of diffusion control on the reaction rate was also observed in a study of the reaction kinetics on supported layers of calcium oxide.

Kossaya, A.M.; Belyakov, B.P.; Kuchma, Z.V.; Sandrozd, M.K.; Vasil'eva, V.G.

1986-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

E-Print Network 3.0 - atmospheric pressure hf Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

for: atmospheric pressure hf Page: << < 1 2 3 4 5 > >> 1 Atomic rearrangements in HfO2Si1-xGex interfaces Deok-Yong Cho and S.-J. Oha Summary: by PDA. PDA was per- formed...

82

Self-fabricated single mode waveguide in fluoride glass excited by self-channeled plasma filaments  

SciTech Connect (OSTI)

Self-fabricated permanent structure of single mode waveguide in optical fluoride glasses was demonstrated using the self-channeled plasma filament excited by a femtosecond (130 fs) Ti:sapphire laser ({lambda}{sub p}=790 nm). The photoinduced refractive index modification in ZrF{sub 4}-BaF{sub 2}-LaF{sub 3}-AlF{sub 3}-NaF glasses reached a length of approximately 10-15 mm from the input surface of the optical glass with the diameters ranging from 5 to 8 {mu}m at the input intensities of more than 1.0x10{sup 12} W/cm{sup 2}. The graded refractive index profiles were fabricated to be a symmetric form from the center of optical fluoride glass, and a maximum value of refractive index change ({delta}n) was measured to be 1.3x10{sup -2}. The beam profile of the output beam transmitted through the modified region showed that the photoinduced refractive index modification produced a permanent structure of single mode waveguide.

Cho, Sung-Hak; Chang, Won-Seok; Kim, Jae-Goo; Whang, Kyoung-Hyun [Nano Machining Laboratory, Korea Institute of Machinery and Material (KIMM), 171 Jang-dong, Yuseong-Gu, Daejeon 305-343 (Korea, Republic of)

2007-09-17T23:59:59.000Z

83

The effect of fluoride and aluminum on the anion exchange of plutonium from nitric acid  

SciTech Connect (OSTI)

Anion exchange in nitric acid is a prominent aqueous process used to recover and purify plutonium from impure nuclear materials. This process is sensitive to fluoride ion, which complexes plutonium in competition with the anionic nitrato complex that is strongly sorbed on the anion exchange column. Fluoride interference traditionally has been counteracted by adding a masking agent, such as aluminum, that forms competing complexes with fluoride. The interfering effect of fluoride is known to be a function not only of the fluoride-to-aluminum ratio but also of the fluoride-to-plutonium ratio. This report summarizes a Los Alamos study of the effect of 25 fluoride-aluminum-plutonium conmbinations on the anion exchange sorption of plutonium. Five aluminum-to-plutonium ratios ranging from 0.10 to 10 were each evaluated at five fluoride-to-aluminum ratios that ranged from 0 to 6. The fluoride-to-plutonium ratio has a greater influence on plutonium sorption than does the fluoride-to-aluminum ratio. Aluminum was less effective as a masking agent than had been assumed, because measurable fluoride interference occurred at all levels of added aluminum.

Marsh, S.F.

1987-07-01T23:59:59.000Z

84

Capacitive Behavior of HF Power Transformers: Global Approach to Draw Robust Equivalent Circuits  

E-Print Network [OSTI]

behavior of all components. Among these components, HF power transformers constitute a special case. EvenCapacitive Behavior of HF Power Transformers: Global Approach to Draw Robust Equivalent Circuits of n-windings HF power transformers. A global approach, mainly based on energy considerations about

Paris-Sud XI, Université de

85

Effect of Al addition on the microstructure and electronic structure of HfO2 film  

E-Print Network [OSTI]

Effect of Al addition on the microstructure and electronic structure of HfO2 film X. F. Wang investigated the microstructures and electronic structures of a series of hafnium aluminate HfAlO films with Al concentration ranging from 0% to 100%. When the films evolve from pure HfO2 to pure Al2O3 by increasing

Gong, Xingao

86

EIS-0359: Uranium Hexafluoride Conversion Facility at the Paducah, Kentucky Site  

Broader source: Energy.gov [DOE]

This site-specific EIS considers the construction, operation, maintenance, and decontamination and decommissioning of the proposed depleted uranium hexafluoride (DUF6) conversion facility at three locations within the Paducah site; transportation of depleted uranium conversion products and waste materials to a disposal facility; transportation and sale of the hydrogen fluoride (HF) produced as a conversion co-product; and neutralization of HF to calcium fluoride and its sale or disposal in the event that the HF product is not sold.

87

Structural studies of magnesium nitride fluorides by powder neutron diffraction  

SciTech Connect (OSTI)

Samples of ternary nitride fluorides, Mg{sub 3}NF{sub 3} and Mg{sub 2}NF have been prepared by solid state reaction of Mg{sub 3}N{sub 2} and MgF{sub 2} at 1323-1423 K and investigated by powder X-ray and powder neutron diffraction techniques. Mg{sub 3}NF{sub 3} is cubic (space group: Pm3m) and has a structure related to rock-salt MgO, but with one cation site vacant. Mg{sub 2}NF is tetragonal (space group: I4{sub 1}/amd) and has an anti-LiFeO{sub 2} related structure. Both compounds are essentially ionic and form structures in which nitride and fluoride anions are crystallographically ordered. The nitride fluorides show temperature independent paramagnetic behaviour between 5 and 300 K. - Graphical abstract: Definitive structures of the ternary magnesium nitride fluorides Mg{sub 3}NF{sub 3} and the lower temperature polymorph of Mg{sub 2}NF have been determined from powder neutron diffraction data. The nitride halides are essentially ionic and exhibit weak temperature independent paramagnetic behaviour. Highlights: Black-Right-Pointing-Pointer Definitive structures of Mg{sub 3}NF{sub 3} and Mg{sub 2}NF were determined by neutron diffraction. Black-Right-Pointing-Pointer Nitride and fluoride anions are crystallographically ordered in both structures. Black-Right-Pointing-Pointer Both compounds exhibit weak, temperature independent paramagnetic behaviour. Black-Right-Pointing-Pointer The compounds are essentially ionic with ionicity increasing with F{sup -} content.

Brogan, Michael A. [School of Chemistry, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Hughes, Robert W. [WestCHEM, School of Chemistry, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Smith, Ronald I. [ISIS Pulsed Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX (United Kingdom); Gregory, Duncan H., E-mail: Duncan.Gregory@glasgow.ac.uk [WestCHEM, School of Chemistry, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

2012-01-15T23:59:59.000Z

88

Low temperature cold trapping of uranium hexafluoride containing hydrogen fluoride  

SciTech Connect (OSTI)

The use of a freezer-sublimer system operating at low desublimation pressures to replace 10-in. nuclearly safe cold traps for low assay (<5% U-235) uranium hexafluoride (UF{sub 6}) would significantly simplify operations and is economically attractive provided the nuclear safety of the system can be assured. A major requirement of such assurance is the availability of conditions guaranteeing that the nuclear safety design criterion, which requires that the H/U atomic ratio in the condensate in the freezer-sublimer always be less than 0.33 for assays up to 5%, will never be violated. A general vapor pressure equation giving the vapor pressure of HF-UF{sub 6} solutions as a function of temperature and mole fraction UF{sub 6} has been developed. The precision of the data at the 95% confidence level is {plus minus}0.1 torr at temperatures between {minus}100{degree}F and {minus}121{degree}F. The calculated vapor pressure of pure HF is 4.6 torr at {minus}100{degree}F and 3.1 torr at {minus}108{degree}F. Theoretical considerations suggest that the true value will be slightly lower. In experimental studies of the cold trapping operation at {minus}108{degree}F and at a trap pressure of 2.2 torr, only 7.3% of the HF entering the trap was retained in the trap. At a trap pressure of 4.6 torr, over 80% of the HF entering the trap was retained. The data obtained in this study confirms that the physical chemistry of the HF-UF{sub 6} system previously developed accurately describes the behavior of the system and that so long as the pressure in the trap is maintained below the vapor pressure of pure HF at the trap temperatures, there is no way that sufficient HF can be trapped to give an H/U ratio of 0.33 regardless of the HF/UF{sub 6} ratio in the feed to the trap. 5 refs., 4 tabs.

Hobbs, W.E.; Barber, E.J.; Jones, C.G.

1990-10-01T23:59:59.000Z

89

Comparison of the Ca+HF(DF) and Sr+HF(DF) reaction dynamics Rong Zhang, David J. Rakestraw,a) Kenneth G. McKendrick,b) and Richard N. Zare  

E-Print Network [OSTI]

Comparison of the Ca+HF(DF) and Sr+HF(DF) reaction dynamics Rong Zhang, David J. Rakestraw family, Ca and Sr with rovibrationally selected HF or DF, has been carried out under single-collision conditions. A thermal beam of the alkaline earth atoms, Ca or Sr, is fired into a low-pressure gas of HF

Zare, Richard N.

90

Intrinsic metastability of orthorhombic HfTiO{sub 4} in thin film hafnia-titania  

SciTech Connect (OSTI)

Orthorhombic (o) HfTiO{sub 4} is crystallized when sputter deposited hafnia-titania nanolaminates with ultrathin layers and bilayer (HfO{sub 2}){sub 0.5}(TiO{sub 2}){sub 0.5} composition are annealed between 573 and 1173 K. However, o-HfTiO{sub 4} demixes after annealing at 1273 K, a result not predicted from bulk thermodynamics. X-ray diffraction and Raman microscopy are used here to study structural changes as o-HfTiO{sub 4} demixes upon long-term annealing at 1273 K into Ti-doped monoclinic HfO{sub 2} and Hf-doped rutile TiO{sub 2}. We conclude that o-HfTiO{sub 4} crystallized at low temperature is intrinsically metastable. A space group symmetry analysis shows that demixing can be accomplished by a continuous phase transition chain.

Cisneros-Morales, Massiel Cristina; Aita, Carolyn Rubin [Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States)

2011-01-31T23:59:59.000Z

91

Determination of naphthenic acids in California crudes and refinery waste waters by fluoride ion chemical ionization mass spectrometry  

SciTech Connect (OSTI)

A method based on negative ion chemical ionization mass spectrometry using fluoride (F/sup -/) ions produced from NF/sub 3/ reagent gas has been applied to the analysis of naphthenic acids in California crude oils and refinery waste waters. Since complex mixtures of naphthenic acids cannot be separated into individual components, only the determination of relative distribution of acids classified by the hydrogen deficiency was possible. The identities and relative distribution of paraffinic and mono-, di-, tri, and higher polycyclic acids were obtained from the intensities of the carboxylate (RCOO/sup -/) ions.

Dzidic, I.; Somerville, A.C.; Raia, J.C.; Hart, H.V.

1988-07-01T23:59:59.000Z

92

Growth, microstructure and electrical properties of sputter-deposited hafnium oxide (HfO2) thin films grown using HfO2 ceramic target  

SciTech Connect (OSTI)

Hafnium oxide (HfO?) thin films have been made by radio-frequency (rf) magnetron-sputtering onto Si(100) substrates under varying growth temperature (Ts). HfO? ceramic target has been employed for sputtering while varying the Ts from room temperature to 500?C during deposition. The effect of Ts on the growth and microstructure of deposited HfO? films has been studied using grazing incidence x-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and high-resolution scanning electron microscopy (HR-SEM) coupled with energy dispersive x-ray spectrometry (EDS). The results indicate that the effect of Ts is significant on the growth, surface and interface structure, morphology and chemical composition of the HfO? films. Structural characterization indicates that the HfO? films grown at Ts<200 ?C are amorphous while films grown at Ts>200 ?C are nanocrystalline. An amorphous-to-crystalline transition occurs at Ts=200 ?C. Nanocrystalline HfO? films crystallized in a monoclinic structure with a (-111) orientation. XPS measurements indicated the high surface-chemical quality and stoichiometric nature of the grown HfO? films. An interface layer (IL) formation occurs due to reaction at the HfO?-Si interface for HfO? films deposited at Ts>200 ?C. The thickness of IL increases with increasing Ts. XPS and EDS at the HfO?-Si cross-section indicate the IL is a (Hf, Si)-O compound. The electrical characterization using capacitance-voltage measurements indicate that the dielectric constant decreases from 25 to 16 with increasing Ts.

Aguirre, B.; Vemuri, R. S.; Zubia, David; Engelhard, Mark H.; Shutthanandan, V.; Kamala Bharathi, K.; Ramana, Chintalapalle V.

2011-01-01T23:59:59.000Z

93

Luminescence from Edge Fracture in Shocked Lithium Fluoride Crystals  

SciTech Connect (OSTI)

Light emitted from a [100] lithium fluoride crystal was characterized under shock wave compression to 28GPa followed by complete stress release at the edges. The light was examined using time-gated optical spectrometry and imaging, time-resolved optical emission measurements, and hydrodynamic modeling. The shock arrival at the circumference of the crystal was delayed relative to the center so that the two regions could be studied at different times. The majority of the light emission originated when the shock waves released at the circumference of the crystal. Unlike previously reported results for shocked lithium fluoride, we found that the light spectrum is not strictly broad band, but has spectral lines associated with atomic lithium in addition to a broad band background. Also, the emission spectrum depends strongly on the gas surrounding the sample. Based on our observations, the line emission appears to be related to fracture of the lithium fluoride crystal from the shock wave releasing at the edges. Experimenters frequently utilize lithium fluoride crystals as transparent windows for observing shock compressed samples. Because of the experimental geometries used, the shock wave in such cases often reaches the circumference of the window at nearly the same moment as when it reaches the center of the sample-window interface. Light generated at the circumference could contaminate the measurement at the interface when this light scatters into the observed region. This background light may be reduced or avoided using experimental geometries which delay the arrival of the shock wave at the edges of the crystal.

Turley, W. D. [NSTec; Stevens, G. D. [NSTec; Capelle, G. A. [NSTec; Grover, M. [NSTec; Holtkamp, D. B. [LANL; LaLone, B. M. [NSTec; Veeser, L. R. [NSTec, LANL

2013-04-01T23:59:59.000Z

94

E-Print Network 3.0 - americium fluorides Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

REPRODUCTION Summary: Tritium Uranium Z34 Americium Z41 Cesium i37 Radium ZZ6 Strontium 90 Chloride Fluoride Nit rate Dissolved... Alpha (unidentified) Beta (Unidentified)...

95

E-Print Network 3.0 - alkaline earth fluorides Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in Earth's mantle formed by liquid immiscibility Stephan Klemme... . The light rare earth elements (LREEs), Sr, and Ba are partitioned into the fluoride melt, whereas the...

96

Grout formulation for disposal of low-level and hazardous waste streams containing fluoride  

DOE Patents [OSTI]

A composition and related process for disposal of hazardous waste streams containing fluoride in cement-based materials is disclosed. the presence of fluoride in cement-based materials is disclosed. The presence of fluoride in waste materials acts as a set retarder and as a result, prevents cement-based grouts from setting. This problem is overcome by the present invention wherein calcium hydroxide is incorporated into the dry-solid portion of the grout mix. The calcium hydroxide renders the fluoride insoluble, allowing the grout to set up and immobilize all hazardous constituents of concern. 4 tabs.

McDaniel, E.W.; Sams, T.L.; Tallent, O.K.

1987-06-02T23:59:59.000Z

97

E-Print Network 3.0 - arsenic fluorides Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

(F), selenium (Se), uranium (U), and radium... : arsenic, fluoride, nitrate, selenium, uranium, and ... Source: Scanlon, Bridget R. - Bureau of Economic Geology, Department of...

98

E-Print Network 3.0 - ab initio hf Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

for: ab initio hf Page: << < 1 2 3 4 5 > >> 1 imageslogoetsf Introduction Electron Energy Loss Spectroscopy Applications: Nanotubes and Graphene Perspectives Summary: of...

99

Kinetics of aluminum fluoride complexation in acidic waters  

SciTech Connect (OSTI)

Acidic deposition has an important effect on the transport and speciation of soluble aluminum. Toxicity of aqueous aluminum seems to be strongly dependent on aluminum speciation and the presence of complexing ligands such as fluoride. A study is reported of the complex formation kinetics of AlF/sup 2 +/ in the environmentally significant pH range 2.9-4.9. The pH and temperature dependencies of the overall rate of reaction are discussed along with environmental implications for areas subjected to acidic deposition. 22 references, 6 figures, 4 tables.

Plankey, B.J.; Patterson, H.H.; Cronan, C.S.

1986-02-01T23:59:59.000Z

100

The system ammonium fluoride-hydrogen fluoride-water at zero degrees centigrade and at minus twenty degrees centigrade  

E-Print Network [OSTI]

borate formed s1nce the boric acid itself is so weak that it has no measurable effect upon the hydrogen ion concentration. The 1ndicator recommended is brom cresol green and the reactions are: + NHs + HsBOs ? y NHg + HsBO3 HsO+ + HsBOs ? } Hs...ately neutralizes the hydrogen fluoride in the sample and prevents loss from reac- tion with the glass . The flask is then made up to volume. b) 50 milliliters each of saturated aqueous boric acid solution and distilled water are poured into a 500-ml...

Buettner, John Philip

1961-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Hf isotope compositions of northern Luzon arc lavas suggest involvement of pelagic sediments in their source  

E-Print Network [OSTI]

1 Hf isotope compositions of northern Luzon arc lavas suggest involvement of pelagic sediments passing through the data intersect fields for depleted mantle and pelagic sediments suggesting. The relationship between Nd and Hf isotopic compositions in the Luzon volcanics show that the type of sediment

Boyer, Edmond

102

Finland HF and Esrange MST radar observations of polar mesosphere summer echoes  

E-Print Network [OSTI]

Finland HF and Esrange MST radar observations of polar mesosphere summer echoes Tadahiko Ogawa1 (200x) xx:1­8 Finland HF and Esrange MST radar observations of polar mesosphere summer echoes Tadahiko in Finland are presented. The echoes were detected at four frequencies of 9, 11, 13 and 15 MHz at slant

Kirkwood, Sheila

103

Interfacial and structural properties of sputtered HfO{sub 2} layers  

SciTech Connect (OSTI)

Magnetron sputtered HfO{sub 2} layers formed on a heated Si substrate were studied by spectroscopic ellipsometer (SE), x-ray diffraction (XRD), Fourier transform infrared (FTIR), and x-ray photoelectron spectroscopy (XPS) depth profiling techniques. The results show that the formation of a SiO{sub x} suboxide layer at the HfO{sub 2}/Si interface is unavoidable. The HfO{sub 2} thickness and suboxide formation are highly affected by the growth parameters such as sputtering power, O{sub 2}/Ar gas ratio during sputtering, sputtering time, and substrate temperature. XRD spectra show that the deposited film has (111) monoclinic phase of HfO{sub 2}, which is also supported by FTIR spectra. The atomic concentration and chemical environment of Si, Hf, and O have been measured as a function of depth starting from the surface of the sample by XPS technique. It shows that HfO{sub 2} layers of a few nanometers are formed at the top surface. Below this thin layer, Si-Si bonds are detected just before the Si suboxide layer, and then the Si substrate is reached during the depth profiling by XPS. It is clearly understood that the highly reactive sputtered Hf atoms consume some of the oxygen atoms from the underlying SiO{sub 2} to form HfO{sub 2}, leaving Si-Si bonds behind.

Aygun, G. [Department of Physics, Izmir Institute of Technology, Urla, TR-35430 Izmir (Turkey); Yildiz, I. [Department of Physics, Middle East Technical University, TR-06531 Ankara (Turkey); Central Laboratory, Middle East Technical University, TR-06531 Ankara (Turkey)

2009-07-01T23:59:59.000Z

104

A Study of the Grain Boundaries and Hydrogen in HF-CVD Diamond Films  

E-Print Network [OSTI]

composition of grain boundaries in polycrystalline diamond lms by transmission electron microscopy and highA Study of the Grain Boundaries and Hydrogen in HF-CVD Diamond Films Israel Yoel Koenka #12;A Study of the Grain Boundaries and Hydrogen in HF-CVD Diamond Films Research Thesis In partial fulllment

Adler, Joan

105

Ca+HF: The anatomy of a chemical insertion reaction R. L. Jaffe  

E-Print Network [OSTI]

Ca+HF: The anatomy of a chemical insertion reaction R. L. Jaffe NASA Ames Research Center, Moffett theoretical investigation of the gas phase reaction Ca + HF-CaF + H is reported. The overall study involves electronic state of the Ca-F-H system, (b) careful fitting of the computed surface to an analytical form

Zare, Richard N.

106

Damage thresholds of fluoride multilayers at 355 nm  

SciTech Connect (OSTI)

Fluoride multilayer coatings were evaluated for use in 355 nm high reflector applications. The LaF[sub 3]/Na[sub 3]AlF[sub 6], NdF[sub 3]/Na[sub 3]AlF[sub 6] and GdF[sub 3]/Na[sub 3]AlF[sub 6] multilayers had laser damage thresholds of 20, 17.9 and 7.4 (measured at 10-ns pulsewidths), respectively. High tensile stresses in the coatings restricted this evaluation to only 5-layer-pair partial reflectors (49--52%).The LaF[sub 3]/Na[sub 3]AlF[sub 6], NdF[sub 3]/Na[sub 3]Al[sub 6] and GdF[sub 3]/Na[sub 3]AlF[sub 6] multilayers had tensile stresses of [approximately] 1.1 [times] 109, 1.3 [times] 109 and 9.3 [times] 10[sup 8] dynes/cm[sup 2], respectively. Substrate material and glow-discharge processing of the substrates were found to influence the density of stress-induced coating fractures and damage thresholds in some cases. If stress fracturing and scatter can be controlled, these fluoride material combinations are suited for 3[omega] applications.

Chow, R.; Kozlowski, M.R.; Loomis, G.E.; Rainer, F.

1992-10-01T23:59:59.000Z

107

The synthesis and structural characterization of novel transition metal fluorides  

SciTech Connect (OSTI)

High purity KMF[sub 6] and K[sub 2]MF[sub 6] salts (M = Mo,Re, Ru, Os, Ir, Pt) are obtained from reduction hexafluorides. A rhombohedral unit cell is observed for KReF[sub 6]. Fluoride ion capture by Lewis acids from the hexafluorometallate (IV) salts affords high purity tetrafluorides for M = Mo, Re, Ru, Os, and Pd. The structure of RuF[sub 4] is determined from X-ray synchrotron and neutron powder data. Unit cells based on theorthorhombic PdF[sub 4] type cell are derived from X-ray powder data for ReF[sub 4] and OsF[sub 4]. Fluoride ion capture from KAgF[sub 4] provides the thermally unstable trifluoride as a bright, red, diamagnetic solid. The structure solution of AgF[sub 3] and redetermination of the AuF[sub 3] structure from X-ray synchrotron and neutron powder data demonstrate that the two are isostnictural. Thermal decomposition product of AgF[sub 3] is the mixed valence compound Ag[sup II]Ag[sub 2][sup III]F[sub 8]. Several new salts containing the (Ag - F)[sub n][sup n+] chain cation are prepared. The first linear (Ag - F)[sub n][sup n+] chain is observed in AgF[sup +]BF[sub 4 [sup [minus

Casteel, W.J. Jr.

1992-09-01T23:59:59.000Z

108

Proximal renal tubular injury in rats sub-chronically exposed to low fluoride concentrations  

SciTech Connect (OSTI)

Fluoride is usually found in groundwater at a very wide range of concentration between 0.5 and 25 ppm. At present, few studies have assessed the renal effects of fluoride at environmentally relevant concentrations. Furthermore, most of these studies have used insensitive and nonspecific biomarkers of kidney injury. The aim of this study was to use early and sensitive biomarkers to evaluate kidney injury after fluoride exposure to environmentally relevant concentrations. Recently weaned male Wistar rats were exposed to low (15 ppm) and high (50 ppm) fluoride concentrations in drinking water for a period of 40 days. At the end of the exposure period, kidney injury biomarkers were measured in urine and renal mRNA expression levels were assessed by real time RT-PCR. Our results showed that the urinary kidney injury molecule (Kim-1), clusterin (Clu), osteopontin (OPN) and heat shock protein 72 excretion rate significantly increased in the group exposed to the high fluoride concentration. Accordingly, fluoride exposure increased renal Kim-1, Clu and OPN mRNA expression levels. Moreover, there was a significant dose-dependent increase in urinary ?-2-microglobulin and cystatin-C excretion rate. Additionally, a tendency towards a dose dependent increase of tubular damage in the histopathological light microscopy findings confirmed the preferential impact of fluoride on the tubular structure. All of these changes occurred at early stages in which, the renal function was not altered. In conclusion using early and sensitive biomarkers of kidney injury, we were able to found proximal tubular alterations in rats sub-chronically exposed to fluoride. - Highlights: • Exposure to low concentrations of fluoride induced proximal tubular injury • Increase in urinary Kim-1, Clu, OPN and Hsp72 in 50 ppm fluoride-exposed group • Increase in urinary B2M and CysC in 15 and 50 ppm fluoride-exposed groups • Fluoride exposure increased renal Kim, Clu and OPN mRNA expression levels. • Fluoride increased kidney injury biomarkers at stages where eGFR was unaltered.

Cárdenas-González, Mariana C.; Del Razo, Luz M. [Departmento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), México, D. F., México (Mexico); Barrera-Chimal, Jonatan [Unidad de Fisiología Molecular, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México and Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México, D. F., México (Mexico); Jacobo-Estrada, Tania [Departmento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), México, D. F., México (Mexico); López-Bayghen, Esther [Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), México, D. F., México (Mexico); and others

2013-11-01T23:59:59.000Z

109

Crystal structure of Si-doped HfO{sub 2}  

SciTech Connect (OSTI)

Si-doped HfO{sub 2} was prepared by solid state synthesis of the starting oxides. Using Rietveld refinement of high resolution X-ray diffraction patterns, a substitutional limit of Si in HfO{sub 2} was determined as less than 9 at.?%. A second phase was identified as Cristobalite (SiO{sub 2}) rather than HfSiO{sub 4}, the latter of which would be expected from existing SiO{sub 2}-HfO{sub 2} phase diagrams. Crystallographic refinement with increased Si-dopant concentration in monoclinic HfO{sub 2} shows that c/b increases, while ? decreases. The spontaneous strain, which characterizes the ferroelastic distortion of the unit cell, was calculated and shown to decrease with increasing Si substitution.

Zhao, Lili [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); School of Information Science and Technology, Northwest University, Xi'an 710127 (China); Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Nelson, Matthew; Fancher, Chris M. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Aldridge, Henry [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Iamsasri, Thanakorn; Forrester, Jennifer S.; Jones, Jacob L., E-mail: jacobjones@ncsu.edu [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Nishida, Toshikazu [Department of Electrical and Computer Engineering, University of Florida, Gainesville, Florida 32611 (United States); Moghaddam, Saeed [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida 32611 (United States)

2014-01-21T23:59:59.000Z

110

Thermal decomposition of HfCl{sub 4} as a function of its hydration state  

SciTech Connect (OSTI)

The thermogravimetric behavior of HfCl{sub 4} powders with different hydration states has been compared. Strongly hydrated powders consist of HfOCl{sub 2}.nH{sub 2}O with n>4. Partially hydrated powders consist of particles with a HfCl{sub 4} core and a hydrated outerlayer of HfOCl{sub 2}.nH{sub 2}O with n in the range of 0-8. Hydrated powders decomposed at temperature lower than 200 deg. C whereas the decomposition of partially hydrated powders was completed at a temperature of around 450 deg. C. The observed differences in decomposition temperature is related to the structure of HfOCl{sub 2}.nH{sub 2}O, which is different if n is higher or smaller than 4 and leads to intermediate compounds, which decompose at different temperatures.

Barraud, E. [Laboratoire de Science et Genie des Materiaux et de Metallurgie, UMR CNRS INPL 7584, Ecole des Mines, F-54042 Nancy Cedex (France); Begin-Colin, S. [Laboratoire de Science et Genie des Materiaux et de Metallurgie, UMR CNRS INPL 7584, Ecole des Mines, F-54042 Nancy Cedex (France) and Institut de Physique et Chimie des Materiaux, GMI, UMR CNRS-ULP 7504, Ecole de Chimie, Polymeres et Materiaux, 23, rue du Loess, BP 43, F-67034 Strasbourg Cedex 2 (France)]. E-mail: begin@ipcms.u-strasbg.fr; Le Caer, G. [Groupe Matiere Condensee et Materiaux, UMR CNRS-Universite de Rennes-I 6626, Campus de Beaulieu, Batiment 11A, F-35042 Rennes Cedex (France); Villieras, F. [Laboratoire Environnement et Mineralurgie, UMR CNRS-INPL 7569, Ecole Nationale Superieure de Geologie de Nancy, F-54501 Vandoeuvre-les-Nancy Cedex (France); Barres, O. [Laboratoire Environnement et Mineralurgie, UMR CNRS-INPL 7569, Ecole Nationale Superieure de Geologie de Nancy, F-54501 Vandoeuvre-les-Nancy Cedex (France)

2006-06-15T23:59:59.000Z

111

Safety Slide 1 Hydrofluoric (HF) Acid Hazards http://www.emsworld.com/web/online/Education/Hydrofluoric-Acid-/5$12949  

E-Print Network [OSTI]

Safety Slide 1 ­ Hydrofluoric (HF) Acid Hazards http://www.emsworld.com/web may be delayed for up to 24 hours, even with dilute solutions. HF burns affect deep tissue layers

Cohen, Robert E.

112

High performance organic field-effect transistors with ultra-thin HfO{sub 2} gate insulator deposited directly onto the organic semiconductor  

SciTech Connect (OSTI)

We have produced stable organic field-effect transistors (OFETs) with an ultra-thin HfO{sub 2} gate insulator deposited directly on top of rubrene single crystals by atomic layer deposition (ALD). We find that ALD is a gentle deposition process to grow thin films without damaging rubrene single crystals, as results these devices have a negligibly small threshold voltage and are very stable against gate-bias-stress, and the mobility exceeds 1 cm{sup 2}/V s. Moreover, the devices show very little degradation even when kept in air for more than 2 months. These results demonstrate thin HfO{sub 2} layers deposited by ALD to be well suited as high capacitance gate dielectrics in OFETs operating at small gate voltage. In addition, the dielectric layer acts as an effective passivation layer to protect the organic semiconductor.

Ono, S., E-mail: shimpei@criepi.denken.or.jp [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan); Häusermann, R. [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan) [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan); Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland); Chiba, D. [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan) [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 322-0012 (Japan); Department of Applied Physics, University of Tokyo, Tokyo 113-8656 (Japan); Shimamura, K.; Ono, T. [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)] [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Batlogg, B. [Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland)] [Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland)

2014-01-06T23:59:59.000Z

113

The synthesis and structural characterization of novel transition metal fluorides  

SciTech Connect (OSTI)

High purity KMF{sub 6} and K{sub 2}MF{sub 6} salts (M = Mo,Re, Ru, Os, Ir, Pt) are obtained from reduction hexafluorides. A rhombohedral unit cell is observed for KReF{sub 6}. Fluoride ion capture by Lewis acids from the hexafluorometallate (IV) salts affords high purity tetrafluorides for M = Mo, Re, Ru, Os, and Pd. The structure of RuF{sub 4} is determined from X-ray synchrotron and neutron powder data. Unit cells based on theorthorhombic PdF{sub 4} type cell are derived from X-ray powder data for ReF{sub 4} and OsF{sub 4}. Fluoride ion capture from KAgF{sub 4} provides the thermally unstable trifluoride as a bright, red, diamagnetic solid. The structure solution of AgF{sub 3} and redetermination of the AuF{sub 3} structure from X-ray synchrotron and neutron powder data demonstrate that the two are isostnictural. Thermal decomposition product of AgF{sub 3} is the mixed valence compound Ag{sup II}Ag{sub 2}{sup III}F{sub 8}. Several new salts containing the (Ag - F){sub n}{sup n+} chain cation are prepared. The first linear (Ag - F){sub n}{sup n+} chain is observed in AgF{sup +}BF{sub 4 {sup {minus}}} which crystallizes in a tetragonal unit. AgFAuF{sub 4} has a triclinic unit cell and is isostructural with CuFAuF{sub 4}. AgFAuF{sub 6} has an orthorhombic unit cell and appears to be isostructural with AgFAsF{sub 6}. A second mixed valence silver fluoride, Ag{sup II}Ag{sup III}F{sub 5}, is prepared, which magnetic measurements indicate is probably an AgF{sup +} salt. Magnetic data for all of the AgF{sup +} salts exhibit low magnitude, temperature independent paramagnetism characteristic of metallic systems. Cationic AG(II) in acidic AHF solutions is a powerful oxidizer, capable of oxidizing Xe to Xe(II) and O{sub 2} to O{sub 2}{sup +}. Reactions with C{sub 6}F{sub 6} and C{sub 3}F{sub 6} suggest an electron capture mechanism for cationic AG(II) oxidations.

Casteel, W.J. Jr.

1992-09-01T23:59:59.000Z

114

The system silver fluoride - hydrogen fluoride - water at zero degrees centigrade and at minus fifteen degrees centigrade  

E-Print Network [OSTI]

samples from the acid&ass titraticna vere filtered J ' through veigbed fritted glass filter oruclbles~ snd washed with 1 . V 0. 01 I nitrio aoid and vator. %e oruoiblee vere then dried in aa, oven eot at 140 for fogr bcnua, plaoed in a vaomsa... . . and Coupons, Xeu Tork (1952) ~ 'I g 16 I l \\ 1 I ( v' 4 o Al Figure 1 AHF-HF-HFO At 0 C, Figure 2 AHP-HP-H2G At -15 G. o b0 ID III IS Cw IS ...

Thomas, Hiram Jack

2012-06-07T23:59:59.000Z

115

Effect of the isoelectric point on the adsorption of molybdates on fluoride-modified aluminas  

SciTech Connect (OSTI)

The isoelectric point (IEP) of ..gamma..-alumina was modified by the addition of various amounts of fluoride. The modified aluminas were used as supports for molybdenum catalysts prepared by equilibrium adsorption at pH = 6.5. Also, the adsorption of molybdate on supports containing various amounts of fluoride was studied as a function of pH. The amount of molybdenum adsorbed on the fluoride-modified aluminas was found to decrease the IEP of the carrier decreased. An electrostatic model is used to interpret the results. 9 references.

Mulcahy, F.M.; Houalla, M.; Hercules, D.M.

1987-07-01T23:59:59.000Z

116

Removal of impurities from dry scrubbed fluoride enriched alumina  

SciTech Connect (OSTI)

The pot-gas from an aluminum electrolytic cell is cleaned by a dry scrubbing process using fresh alumina as a scrubbing agent. This alumina is enriched with fluorides and trace impurities in a closed loop system with the pots. The only significant removal of the impurities is due to metal tapping. An improved technique has been developed that is more effective than earlier stripper systems. The impurity-rich fine fraction (< 10 {micro}m) of the enriched alumina is partly attached to the coarser alumina. That attachment has to be broken. Selective impact milling under special moderate conditions and air classifying have shown to be a cost effective process for the removal of impurities. For iron (Fe) and phosphorus (P) about 30--70% can be removed by the separation of 0.5--1% of the alumina. Full scale tests have successfully confirmed these results.

Schuh, L. [ABB Corporate Research Center, Heidelberg (Germany); Wedde, G. [ABB Environmental, Oslo (Norway)

1996-10-01T23:59:59.000Z

117

Fluoride Salt-Cooled High-Temperature Reactor Development Roadmap  

SciTech Connect (OSTI)

Fluoride salt-cooled high-temperature reactors (FHRs) are an emerging reactor class with potentially advantageous performance characteristics and fully passive safety. This paper provides an overview of a technology development pathway for expeditious commercial deployment of first-generation FHRs. The paper describes the principal remaining FHR technology challenges and the development path needed to address the challenges. First-generation FHRs do not appear to require any technology breakthroughs, but will require significant technology development and demonstration. FHRs are currently entering early phase engineering development. As such, the development roadmap is not as technically detailed or specific as would be the case for a more mature reactor class. The higher cost of fuel and coolant; the lack of an approved licensing framework; the lack of qualified, salt-compatible structural materials; and the potential for tritium release into the environment are the most obvious issues that remain to be resolved.

Holcomb, David Eugene [ORNL] [ORNL; Flanagan, George F [ORNL] [ORNL; Mays, Gary T [ORNL] [ORNL; Pointer, William David [ORNL] [ORNL; Robb, Kevin R [ORNL] [ORNL; Yoder Jr, Graydon L [ORNL] [ORNL

2014-01-01T23:59:59.000Z

118

Removal of fluoride impurities from UF/sub 6/ gas  

DOE Patents [OSTI]

A method of purifying a UF/sub 6/ gas stream containing one or more metal fluoride impurities composed of a transuranic metal, transition metal or mixtures thereof, is carried out by contacting the gas stream with a bed of UF/sub 5/ in a reaction vessel under conditions where at least one impurity reacts with the UF/sub 5/ to form a nongaseous product and a treated gas stream, and removing the treated gas stream from contact with the bed. The nongaseous products are subsequently removed in a reaction with an active fluorine affording agent to form a gaseous impurity which is removed from the reaction vessel. The bed of UF/sub 5/ is formed by the reduction of UF/sub 6/ in the presence of uv light. One embodiment of the reaction vessel includes a plurality of uv light sources as tubes on which UF/sub 5/ is formed. 2 figures.

Beitz, J.V.

1984-01-06T23:59:59.000Z

119

Evaluation of fluoride-induced metal mobilization in soil columns  

SciTech Connect (OSTI)

Fluoride in soil solution may cause substantially increased leaching of dissolved organic carbon (DOC), Al, and heavy metals from soils. The authors objective was to examine whether increased metal solubility is attributable to formation of fluoro- or organo-complexes. The A horizon of a Slovak soil contaminated with heavy metals and F by Al smelter emissions was used to conduct two column experiments under saturated and steady-state water flow conditions. The columns were leached with 5 mM Na{sub 2}SO{sub 4}, 1 mM NaCl, and 9 mM NaF solutions at pH 5.5 and an electrical conductivity of 1,000 {micro}S cm{sup {minus}1}. Samples were collected in 70-min intervals for approximately 7 d. Two experiments were performed. In the first experiment (single F pulse), a fluoride (F) pulse was applied for 36 pore volumes (PVs), while in the second experiment (dual F pulse), two consecutive F pulses (each for 2.8 PVs) were applied. For both experiments, Cl breakthrough curves (BTCs) revealed a convection-dominated transport regime. The breakthrough of Cd, Cr, Fe, Ni, and Pb paralleled DOC breakthrough in both experiments indicating metal leaching as organocomplex. In the dual F pulse experiment, peak separation of the DOC and the complexed F (F{sub bound}) breakthrough was achieved. The highest F{sub bound} concentration occurred 3.8 PVs later than that of DOC. The AlBTC paralleled that of F{sub bound} but showed tailing with a turning point simultaneous to the highest DOC concentration. Thus, the increase in Al solubility was mainly caused by fluoro-complexation and only to a lesser extent by organo-complexation.

Totsche, K.U.; Wilcke, W.; Koerber, M.; Kobza, J.; Zech, W.

2000-04-01T23:59:59.000Z

120

Role of oxygen vacancy in HfO{sub 2}/SiO{sub 2}/Si(100) interfaces  

SciTech Connect (OSTI)

We have investigated the interface states in HfO{sub 2}/SiO{sub 2}/Si(100) systems that were prepared by using the in situ pulsed laser deposition technique. X-ray photoelectron spectroscopy data revealed that when the HfO{sub 2} film thickness exceeds 11 A, the film composition undergoes a systematic change from Hf silicate to oxygen-deficient HfO{sub x<2}. Furthermore, we determined that the evolution of the interface states clearly depends on the oxygen condition applied during the film growth and that the oxygen vacancy is an important parameter for Hf silicate formation.

Cho, Deok-Yong; Oh, S.-J.; Chang, Y.J.; Noh, T.W.; Jung, Ranju; Lee, Jae-Cheol [CSCMR and School of Physics, Seoul National University, Seoul 151-747 (Korea, Republic of); ReCOE and School of Physics, Seoul National University, Seoul 151-747 (Korea, Republic of); Samsung Advanced Institute of Technology, Suwon 440-900 (Korea, Republic of)

2006-05-08T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Towards forming-free resistive switching in oxygen engineered HfO{sub 2?x}  

SciTech Connect (OSTI)

We have investigated the resistive switching behavior in stoichiometric HfO{sub 2} and oxygen-deficient HfO{sub 2?x} thin films grown on TiN electrodes using reactive molecular beam epitaxy. Oxygen defect states were controlled by the flow of oxygen radicals during thin film growth. Hard X-ray photoelectron spectroscopy confirmed the presence of sub-stoichiometric hafnium oxide and defect states near the Fermi level. The oxygen deficient HfO{sub 2?x} thin films show bipolar switching with an electroforming occurring at low voltages and low operating currents, paving the way for almost forming-free devices for low-power applications.

Sharath, S. U., E-mail: sharath@oxide.tu-darmstadt.de; Kurian, J.; Hildebrandt, E.; Alff, L. [Institute of Materials Science, Technische Universität Darmstadt, Alarich-Weiss-Strasse 2, 64287 Darmstadt (Germany); Bertaud, T.; Walczyk, C.; Calka, P.; Zaumseil, P.; Sowinska, M.; Walczyk, D. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Gloskovskii, A. [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg (Germany); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Brandenburgische Technische Universität, Konrad-Zuse-Strasse 1, 03046 Cottbus (Germany)

2014-02-10T23:59:59.000Z

122

Low energy N{sub 2} ion bombardment for removal of (HfO{sub 2}){sub x}(SiON){sub 1-x} in dilute HF  

SciTech Connect (OSTI)

The ion assisted wet removal of (HfO{sub 2}){sub x}(SiON){sub 1-x} high dielectric constant (k) materials and its effect on electrical properties were investigated. Crystallization temperature of (HfO{sub 2}){sub x}(SiON){sub 1-x} increased as the percentage of SiON increased. The crystallized (HfO{sub 2}){sub 0.6}(SiON){sub 0.4} was damaged and turned to an amorphous film via incorporation of N species into the film by N{sub 2} plasma treatment. In addition, the structure of (HfO{sub 2}){sub 0.6}(SiON){sub 0.4} was disintegrated into HfO{sub 2}, SiO(N), and ON after N{sub 2} plasma treatment. N{sub 2} plasmas using low bias power were applied for wet removal of high-k films and the mechanism of the ion assisted wet removal process was explored. When high bias power was applied, the surface of source and drain regions was nitrided via the reaction between N and Si substrates. Feasibility of the low bias power assisted wet removal process was demonstrated for short channel high-k metal oxide semiconductor device fabrication by the smaller shift of threshold voltage, compared to the high bias power assisted wet removal process as well as the wet-etching-only process.

Hwang, Wan Sik; Cho, Byung-Jin; Chan, Daniel S. H.; Yoo, Won Jong [Silicon Nano Device Laboratory, Department of Electrical and Computer Engineering, National University of Singapore, E4A 02-04, Engineering Drive 3, 117576 Singapore (Singapore); SKKU Advanced Institute of Nanotechnology (SAINT) and Department of Mechanical Engineering, Sungkyunkwan University 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746 (Korea, Republic of)

2007-07-15T23:59:59.000Z

123

Mixed cation phases in sputter deposited HfO{sub 2}-TiO{sub 2} nanolaminates  

SciTech Connect (OSTI)

Nanolaminate HfO{sub 2}-TiO{sub 2} films are grown by reactive sputter deposition on unheated fused SiO{sub 2}, sequentially annealed at 573 to 973 K, and studied by x-ray diffraction. A nanocrystalline structure of orthorhombic (o) HfTiO{sub 4} adjacent to an interface followed by monoclinic (m) Hf{sub 1-x}Ti{sub x}O{sub 2} is identified. m-Hf{sub 1-x}Ti{sub x}O{sub 2}, a metastable phase, is isomorphous with m-HfO{sub 2} and a high pressure phase, m-HfTiO{sub 4}. A Vegard's law analysis shows that the Ti atomic fraction in m-Hf{sub 1-x}Ti{sub x}O{sub 2} is much greater than Ti equilibrium solubility in m-HfO{sub 2}. A space group-subgroup argument proposes that m-Hf{sub 1-x}Ti{sub x}O{sub 2} arises from an o/m-HfTiO{sub 4} second order phase transition to accommodate the larger Hf atom.

Cisneros-Morales, M. C.; Aita, C. R. [Advanced Coatings Experimental Laboratory, College of Engineering and Applied Science, University of Wisconsin-Milwaukee, P.O. Box 784, Milwaukee, Wisconsin 53201 (United States)

2008-07-14T23:59:59.000Z

124

A new buffer system for the potentiometric determination of fluoride ion  

SciTech Connect (OSTI)

This paper attempts to eliminate the lengthy stage of hydrolytic separation of the elements during the potentiometric determination of fluoride ions and also to develop a universal method for the determination of flouride ions. During the development of a procedure for the determination of fluoride ions it is necessary to eliminate the interfering effects of elements which form stable fluoride complexes such as A1 (III), Fe (III), Si (III), Ti (IV), V (IV), Mo (V), and W (V). By the addition of diethylenetriaminepentaacetate to the buffer solution and preliminary extraction of the benzoylphenylhydroxylaminates of the interfering elements with chloroform it was possible to develop a method for the determination of fluoride with a detection limit of 1.10/sup -5/ M.

Zhobinskii, E.Y.; Askochenskaya, R.M.; Novikova, L.B; Wl' Figarov, O.S.

1985-05-01T23:59:59.000Z

125

Energy and momentum transfer of He atoms scattered from a lithium fluoride crystal surface  

E-Print Network [OSTI]

Energy and momentum transfer of He atoms scattered from a lithium fluoride crystal surface H. Legge­surface inter- action is usually described in terms of averaged properties such as the average energy exchange interaction potential has been extensivel

Manson, Joseph R.

126

Characterization Report on Sand, Slag, and Crucible Residues and on Fluoride Residues  

SciTech Connect (OSTI)

This paper reports on the chemical characterization of the sand, slag, and crucible (SS and C) residues and the fluoride residues that may be shipped from the Rocky Flats Environmental Technology Site (RFETS) to Savannah River Site (SRS).

Murray, A.M.

1999-02-10T23:59:59.000Z

127

E-Print Network 3.0 - aluminium fluorides Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

illustrated with interferograms of 1 1 849... performance than our present aluminium-magnesium fluoride coatings at 1800 A. As an example of what is now... ) consist of two S U B...

128

E-Print Network 3.0 - aluminum sodium fluoride Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Information Sciences 28 List of Acronyms, Abbreviations and Symbols Summary: Light Emitting Diode LiAlH4 lithium aluminum hydride LiF lithium fluoride LS Light Scattering...

129

Suppression of interfacial reaction for HfO{sub 2} on silicon by pre-CF{sub 4} plasma treatment  

SciTech Connect (OSTI)

In this letter, the effects of pre-CF{sub 4} plasma treatment on Si for sputtered HfO{sub 2} gate dielectrics are investigated. The significant fluorine was incorporated at the HfO{sub 2}/Si substrate interface for a sample with the CF{sub 4} plasma pretreatment. The Hf silicide was suppressed and Hf-F bonding was observed for the CF{sub 4} plasma pretreated sample. Compared with the as-deposited sample, the effective oxide thickness was much reduced for the pre-CF{sub 4} plasma treated sample due to the elimination of the interfacial layer between HfO{sub 2} and Si substrate. These improved characteristics of the HfO{sub 2} gate dielectrics can be explained in terms of the fluorine atoms blocking oxygen diffusion through the HfO{sub 2} film into the Si substrate.

Lai, C.S.; Wu, W.C.; Chao, T.S.; Chen, J.H.; Wang, J.C.; Tay, L.-L.; Rowell, Nelson [Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan (China); Department of Electronic Physics, National Chiao Tung University, 1001 Ta Hsueh Rd., Hsinchu 300, Taiwan (China); Department of Electronics Engineering, National Chiao Tung University, 1001 Ta Hsueh Rd., Hsinchu 300, Taiwan (China); Nanya Technology Corporation, Hwa-Ya Technology Park, 669 Fu-Hsing 3rd Rd., Kueishan, Taoyuan 338, Taiwan (China); Institute for Microstructural Sciences, National Research Council of Canada, 1200 Montreal Road, Ottawa, Ontario K1A 0R6 (Canada)

2006-08-14T23:59:59.000Z

130

Method for removal of plutonium impurity from americium oxides and fluorides  

DOE Patents [OSTI]

Method for removal of plutonium impurity from americium oxides and fluorides. AmF.sub.4 is not further oxidized to AmF.sub.6 by the application of O.sub.2 F at room temperature, while plutonium compounds present in the americium sample are fluorinated to volatile PuF.sub.6, which can readily be separated therefrom, leaving the purified americium oxides and/or fluorides as the solid tetrafluoride.

FitzPatrick, John R. (Los Alamos, NM); Dunn, Jerry G. (Los Alamos, NM); Avens, Larry R. (Los Alamos, NM)

1987-01-01T23:59:59.000Z

131

Method for removal of plutonium impurity from americium oxides and fluorides  

DOE Patents [OSTI]

Method for removal of plutonium impurity from americium oxides and fluorides. AmF/sub 4/ is not further oxidized to AmF/sub 6/ by the application of O/sub 2/F at room temperature thereto, while plutonium compounds present in the americium sample are fluorinated to volatile PuF/sub 6/, which can readily be separated therefrom, leaving the purified americium oxides and/or fluorides as the solid tetrafluoride thereof.

FitzPatrick, J.R.; Dunn, J.G.; Avens, L.R.

1987-02-13T23:59:59.000Z

132

Physical approaches to controlling the fluoride content of fish protein concentrate  

E-Print Network [OSTI]

by the co-current batch extraction process previously described under section B of this chapter. The re- sulting extracted solids were air dried and retained for ash and fluoride determination. F. Analytical Methods Fluoride contents of the FPC samples... INTRODUCTION LITERATURE REVIEW METHODS AND MATERIALS A. Raw Materials B. Extraction Technique C. Grinding of Coarse FPC D. Selective Screening and Air Classification E. Flotation Approaches F. Analytical Methods 10 RESULTS 13 DIS CUSS ION 33 SUMMARY...

Rahman, Muhammad Asadur

1968-01-01T23:59:59.000Z

133

Uranium hexafluoride liquid thermal expansion, elusive eutectic with hydrogen fluoride, and very first production using chlorine trifluoride  

SciTech Connect (OSTI)

Three unusual incidents and case histories involving uranium hexafluoride in the enrichment facilities of the USA in the late 1940`s and early 1950`s are presented. The history of the measurements of the thermal expansion of liquids containing fluorine atoms within the molecule is reviewed with special emphasis upon uranium hexafluoride. A comparison is made between fluorinated esters, fluorocarbons, and uranium hexafluoride. The quantitative relationship between the thermal expansion coefficient, a, of liquids and the critical temperature, T{sub c} is presented. Uranium hexafluoride has an a that is very high in a temperature range that is used by laboratory and production workers - much higher than any other liquid measured. This physical property of UF{sub 6} has resulted in accidents involving filling the UF{sub 6} containers too full and then heating with a resulting rupture of the container. Such an incident at a uranium gaseous diffusion plant is presented. Production workers seldom {open_quotes}see{close_quotes} uranium hexafluoride. The movement of UF{sub 6} from one container to another is usually trailed by weight, not sight. Even laboratory scientists seldom {open_quotes}see{close_quotes} solid or liquid UF{sub 6} and this can be a problem at times. This inability to {open_quotes}see{close_quotes} the UF{sub 6}-HF mixtures in the 61.2{degrees}C to 101{degrees}C temperature range caused a delay in the understanding of the phase diagram of UF{sub 6}-HF which has a liquid - liquid immiscible region that made the eutectic composition somewhat elusive. Transparent fluorothene tubes solved the problem both for the UF{sub 6}-HF phase diagram as well as the UF{sub 6}-HF-CIF{sub 3} phase diagram with a miscibility gap starting at 53{degrees}C. The historical background leading to the first use of CIF{sub 3} to produce UF{sub 6} in both the laboratory and plant at K-25 is presented.

Rutledge, G.P. [Central Environmental, Inc., Anchorage, AK (United States)

1991-12-31T23:59:59.000Z

134

Germanium diffusion during HfO{sub 2} growth on Ge by molecular beam epitaxy  

SciTech Connect (OSTI)

The authors study the Ge diffusion during HfO{sub 2} growth by molecular beam epitaxy on differently in situ prepared germanium substrates and at different growth temperatures. While HfO{sub 2} layers grown directly on Ge do not show any germanium contamination, oxygen rich interfacial layers such as GeO{sub x} or GeO{sub x}N{sub y} partly dissolve into the HfO{sub 2} layer, giving rise to high Ge contamination (from 1% to 10%). The use of nitridated interfacial layers does not prevent Ge diffusion into the HfO{sub 2} during the growth process because of the high oxygen content present in the nitridated germanium layer.

Ferrari, S.; Spiga, S.; Wiemer, C.; Fanciulli, M.; Dimoulas, A. [Laboratorio MDM-INFM-CNR, Via Olivetti, 2 Agrate Brianza, Milano 20041 (Italy); MBE Laboratory, Institute of Materials Science, DEMOKRITOS National Center for Scientific Research, 153 10 Athens (Greece)

2006-09-18T23:59:59.000Z

135

In situ characterization of initial growth of HfO{sub 2}  

SciTech Connect (OSTI)

The initial growth of HfO{sub 2} on Si (111) is monitored in situ by ultrahigh vacuum (UHV) scanning probe microscopy. UHV scanning tunneling microscopy and UHV atomic force microscopy reveal the topography of HfO{sub 2} films in the initial stage. The chemical composition is further confirmed by x-ray photoelectron spectroscopy. Scanning tunneling spectroscopy is utilized to inspect the evolution of the bandgap. When the film thickness is less than 0.6 nm, the bandgap of HfO{sub 2} is not completely formed. A continuous usable HfO{sub 2} film with thickness of about 1.2 nm is presented in this work.

Wang, L.; Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Xue, K.; Xu, J. B. [Department of Electronic Engineering, Chinese University of Hong Kong, Shatin, New Territories (Hong Kong)

2009-01-19T23:59:59.000Z

136

LuHf isotope systematics of fossil biogenic apatite and their effects on geochronology  

E-Print Network [OSTI]

) and argillaceous matrices with low permeability (oil shale of Messel, Germany; Posidonienschiefer of Holzmaden the Eifel, Germany. Low 176 Lu/177 Hf ratios in all materials from the Middle Eocene Messel oil shale (e

Schöne, Bernd R.

137

Plasma etching of HfO{sub 2} at elevated temperatures in chlorine-based chemistry  

SciTech Connect (OSTI)

Plasma etching of HfO{sub 2} at an elevated temperature is investigated in chlorine-based plasmas. Thermodynamic studies are performed in order to determine the most appropriate plasma chemistry. The theoretical calculations show that chlorocarbon gas chemistries (such as CCl{sub 4} or Cl{sub 2}-CO) can result in the chemical etching of HfO{sub 2} in the 425-625 K temperature range by forming volatile effluents such as HfCl{sub 4} and CO{sub 2}. The etching of HfO{sub 2} is first studied on blanket wafers in a high density Cl{sub 2}-CO plasma under low ion energy bombardment conditions (no bias power). Etch rates are presented and discussed with respect to the plasma parameters. The evolution of the etch rate as function of temperature follows an Arrhenius law indicating that the etching comes from chemical reactions. The etch rate of HfO{sub 2} is about 110 A /min at a temperature of 525 K with a selectivity towards SiO{sub 2} of 15. x-ray photoelectron spectroscopy analyses (XPS) reveal that neither carbon nor chlorine is detected on the HfO{sub 2} surface, whereas a chlorine-rich carbon layer is formed on top of the SiO{sub 2} surface leading to the selectivity between HfO{sub 2} and SiO{sub 2}. A drift of the HfO{sub 2} etch process is observed according to the chamber walls conditioning due to chlorine-rich carbon coatings formed on the chamber walls in a Cl{sub 2}-CO plasma. To get a very reproducible HfO{sub 2} etch process, the best conditioning strategy consists in cleaning the chamber walls with an O{sub 2} plasma between each wafer. The etching of HfO{sub 2} is also performed on patterned wafers using a conventional polysilicon gate. The first result show a slight HfO{sub 2} foot at the bottom of the gate and the presence of hafnium oxide-based residues in the active areas.

Helot, M.; Chevolleau, T.; Vallier, L.; Joubert, O.; Blanquet, E.; Pisch, A.; Mangiagalli, P.; Lill, T. [STMicroelectronics, 850 rue Jean Monnet, 38926 Crolles Cedex (France); Laboratoire des Technologies de la Microelectronique, CNRS, 17 rue des martyrs (CEA-LETI), 38054 Grenoble Cedex 09 (France); LTPCM/INPG-CNRS-UJF, 1130 rue de la piscine, 38402 Saint-Martin-d'Heres (France); Applied Materials, 974 E. Arques Ave. M/S 81334, Sunnyvale, California 94086 (United States)

2006-01-15T23:59:59.000Z

138

Subduction Controls of Hf and Nd Isotopes in Lavas of the Aleutian Island Arc  

SciTech Connect (OSTI)

The Hf and Nd isotopic compositions of 71 Quaternary lavas collected from locations along the full length of the Aleutian island arc are used to constrain the sources of Aleutian magmas and to provide insight into the geochemical behavior of Nd and Hf and related elements in the Aleutian subduction-magmatic system. Isotopic compositions of Aleutian lavas fall approximately at the center of, and form a trend parallel to, the terrestrial Hf-Nd isotopic array with {var_epsilon}{sub Hf} of +12.0 to +15.5 and {var_epsilon}{sub Nd} of +6.5 to +10.5. Basalts, andesites, and dacites within volcanic centers or in nearby volcanoes generally all have similar isotopic compositions, indicating that there is little measurable effect of crustal or other lithospheric assimilation within the volcanic plumbing systems of Aleutian volcanoes. Hafnium isotopic compositions have a clear pattern of along-arc increase that is continuous from the eastern-most locations near Cold Bay to Piip Seamount in the western-most part of the arc. This pattern is interpreted to reflect a westward decrease in the subducted sediment component present in Aleutian lavas, reflecting progressively lower rates of subduction westward as well as decreasing availability of trench sediment. Binary bulk mixing models (sediment + peridotite) demonstrate that 1-2% of the Hf in Aleutian lavas is derived from subducted sediment, indicating that Hf is mobilized out of the subducted sediment with an efficiency that is similar to that of Sr, Pb and Nd. Low published solubility for Hf and Nd in aqueous subduction fluids lead us to conclude that these elements are mobilized out of the subducted component and transferred to the mantle wedge as bulk sediment or as a silicate melt. Neodymium isotopes also generally increase from east to west, but the pattern is absent in the eastern third of the arc, where the sediment flux is high and increases from east to west, due to the presence of abundant terrigenous sediment in the trench east of the Amlia Fracture Zone, which is being subducting beneath the arc at Seguam Island. Mixing trends between mantle wedge and sediment end members become flatter in Hf-Nd isotope space at locations further west along the arc, indicating that the sediment end member in the west has either higher Nd/Hf or is more radiogenic in Hf compared to Nd. This pattern is interpreted to reflect an increase in pelagic clay relative to the terrigenous subducted sedimentary component westward along the arc. Results of this study imply that Hf does not behave as a conservative element in the Aleutian subduction system, as has been proposed for some other arcs.

Yogodzinski, Gene; Vervoort, Jeffery; Brown, Shaun Tyler; Gerseny, Megan

2010-08-29T23:59:59.000Z

139

Chemical states and electronic structure of a HfO(-2) / Ge(001) interface  

SciTech Connect (OSTI)

We report the chemical bonding structure and valence band alignment at the HfO{sub 2}/Ge (001) interface by systematically probing various core level spectra as well as valence band spectra using soft x-rays at the Stanford Synchrotron Radiation Laboratory. We investigated the chemical bonding changes as a function of depth through the dielectric stack by taking a series of synchrotron photoemission spectra as we etched through the HfO{sub 2} film using a dilute HF-solution. We found that a very non-stoichiometric GeO{sub x} layer exists at the HfO{sub 2}/Ge interface. The valence band spectra near the Fermi level in each different film structure were carefully analyzed, and as a result, the valence band offset between Ge and GeO{sub x} was determined to be {Delta}E{sub v} (Ge-GeO{sub x}) = 2.2 {+-} 0.15 eV, and that between Ge and HfO{sub 2}, {Delta}E{sub v} (Ge-HfO{sub 2}) = 2.7 {+-} 0.15 eV.

Seo, Kang-ill; McIntyre, Paul C.; /Stanford U., Materials Sci. Dept.; Sun, Shiyu; Lee, Dong-Ick; Pianetta, Piero; /SLAC, SSRL; Saraswat, Krishna C.; /Stanford U., Elect.

2005-05-04T23:59:59.000Z

140

HfO{sub x}N{sub y} gate dielectric on p-GaAs  

SciTech Connect (OSTI)

Plasma nitridation method is used for nitrogen incorporation in HfO{sub 2} based gate dielectrics for future GaAs-based devices. The nitrided HfO{sub 2} (HfO{sub x}N{sub y}) films on p-GaAs improve metal-oxide-semiconductor device characteristics such as interface state density, accumulation capacitance, hysteresis, and leakage current. An equivalent oxide thickness of 3.6 nm and a leakage current density of 10{sup -6} A cm{sup -2} have been achieved at V{sub FB}-1 V for nitrided HfO{sub 2} films. A nitride interfacial layer (GaAsO:N) was observed at HfO{sub 2}-GaAs interface, which can reduce the outdiffusion of elemental Ga and As during post-thermal annealing process. Such suppression of outdiffusion led to a substantial enhancement in the overall dielectric properties of the HfO{sub 2} film.

Dalapati, G. K.; Sridhara, A.; Wong, A. S. W.; Chia, C. K.; Chi, D. Z. [Institute of Materials Research and Engineering, A-STAR - Agency for Science, Technology and Research, 3 Research Link, Singapore 117602 (Singapore)

2009-02-16T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

First-principles phase diagram calculations for the HfCTiC, ZrCTiC, and HfCZrC solid O. Adjaoud,1,*,  

E-Print Network [OSTI]

Transition metal carbides, including the NaCl-structured group IV Ti, Zr, and Hf carbides, have extremely of oxidizing agents, and retain good corrosion resistance to high temperature.1,5,6 The transition-metal high melting points and are therefore referred to collectively as the "refractory carbides

Steinle-Neumann, Gerd

142

Chemistry control and corrosion mitigation of heat transfer salts for the fluoride salt reactor (FHR)  

SciTech Connect (OSTI)

The Molten Salt Reactor Experiment (MSRE) was a prototype nuclear reactor which operated from 1965 to 1969 at Oak Ridge National Laboratory. The MSRE used liquid fluoride salts as a heat transfer fluid and solvent for fluoride based {sup 235}U and {sup 233}U fuel. Extensive research was performed in order to optimize the removal of oxide and metal impurities from the reactor's heat transfer salt, 2LiF-BeF{sub 2} (FLiBe). This was done by sparging a mixture of anhydrous hydrofluoric acid and hydrogen gas through the FLiBe at elevated temperatures. The hydrofluoric acid reacted with oxides and hydroxides, fluorinating them while simultaneously releasing water vapor. Metal impurities such as iron and chromium were reduced by hydrogen gas and filtered out of the salt. By removing these impurities, the corrosion of reactor components was minimized. The Univ. of Wisconsin - Madison is currently researching a new chemical purification process for fluoride salts that make use of a less dangerous cleaning gas, nitrogen trifluoride. Nitrogen trifluoride has been predicted as a superior fluorinating agent for fluoride salts. These purified salts will subsequently be used for static and loop corrosion tests on a variety of reactor materials to ensure materials compatibility for the new FHR designs. Demonstration of chemistry control methodologies along with potential reduction in corrosion is essential for the use of a fluoride salts in a next generator nuclear reactor system. (authors)

Kelleher, B. C.; Sellers, S. R.; Anderson, M. H.; Sridharan, K.; Scheele, R. D. [Dept. of Engineering Physics, Univ.of Wisconsin - Madison, 1500 Engineering Drive, Madison, WI 53706 (United States)

2012-07-01T23:59:59.000Z

143

Thermally-driven H interaction with HfO{sub 2} films deposited on Ge(100) and Si(100)  

SciTech Connect (OSTI)

In the present work, we investigated the thermally-driven H incorporation in HfO{sub 2} films deposited on Si and Ge substrates. Two regimes for deuterium (D) uptake were identified, attributed to D bonded near the HfO{sub 2}/substrate interface region (at 300?°C) and through the whole HfO{sub 2} layer (400–600?°C). Films deposited on Si presented higher D amounts for all investigated temperatures, as well as, a higher resistance for D desorption. Moreover, HfO{sub 2} films underwent structural changes during annealings, influencing D incorporation. The semiconductor substrate plays a key role in this process.

Soares, G. V., E-mail: gabriel.soares@ufrgs.br; Feijó, T. O. [Instituto de Física, UFRGS, Porto Alegre 91509-900 (Brazil); Baumvol, I. J. R. [Instituto de Física, UFRGS, Porto Alegre 91509-900 (Brazil); Universidade de Caxias do Sul, Caxias do Sul 95070-560 (Brazil); Aguzzoli, C. [Universidade de Caxias do Sul, Caxias do Sul 95070-560 (Brazil); Krug, C. [Instituto de Física, UFRGS, Porto Alegre 91509-900 (Brazil); CEITEC S.A., Porto Alegre 91550-000 (Brazil); Radtke, C. [Instituto de Química, UFRGS, Porto Alegre 91509-900 (Brazil)

2014-01-27T23:59:59.000Z

144

Spectroscopic analysis of Al and N diffusion in HfO{sub 2}  

SciTech Connect (OSTI)

X-ray photoelectron core level spectroscopy, secondary ion mass spectroscopy, spectroscopic ellipsometry, and extended x-ray absorption fine structure measurements have been employed to distinguish the effects of Al and N diffusion on the local bonding and microstructure of HfO{sub 2} and its interface with the Si substrate in (001)Si/SiO{sub x}/2 nm HfO{sub 2}/1 nm AlO{sub x} film structures. The diffusion of Al from the thin AlO{sub x} cap layer deposited on both annealed and unannealed HfO{sub 2} has been observed following anneal in N{sub 2} and NH{sub 3} ambient. Both N{sub 2} and NH{sub 3} subsequent anneals were performed to decouple incorporated nitrogen from thermal reactions alone. Causal variations in the HfO{sub 2} microstructure combined with the dependence of Al and N diffusion on initial HfO{sub 2} conditions are presented with respect to anneal temperature and ambient.

Lysaght, P. S.; Price, J.; Kirsch, P. D. [SEMATECH, 257 Fuller Rd, Albany, New York 12203 (United States); Woicik, J. C.; Weiland, C. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Sahiner, M. A. [Seton Hall University, 400 South Orange Ave, South Orange, New Jersey 07079 (United States)

2012-09-15T23:59:59.000Z

145

HF treatment effect for carbon deposition on silicon (111) by DC sputtering technique  

SciTech Connect (OSTI)

Surface modifications of Si (111) substrate by HF solution for thin film carbon deposition have been systematically studied. Thin film carbon on Si (111) has been deposited using DC Unbalanced Magnetron Sputtering with carbon pellet doped by 5% Fe as the target. EDAX characterization confirmed that the carbon fraction on Si substrate much higher by dipping a clean Si substrate by HF solution before sputtering process in comparison with carbon fraction on Si substrate just after conventional RCA. Moreover, SEM and AFM images show the uniform thin film carbon on Si with HF treatment, in contrast to the Si without HF solution treatment. These experimental results suggest that HF treatment of Si surface provide Si-H bonds on top Si surface that useful to enhance the carbon deposition during sputtering process. Furthermore, we investigate the thermal stability of thin film carbon on Si by thermal annealing process up to 900 °C. Atomic arrangements during annealing process were characterized by Raman spectroscopy. Raman spectra indicate that thin film carbon on Si is remaining unchanged until 600 °C and carbon atoms start to diffuse toward Si substrate after annealing at 900 °C.

Aji, A. S., E-mail: aji.ravazes70@gmail.com; Darma, Y., E-mail: aji.ravazes70@gmail.com [Quantum Semiconductor and Devices Lab., Physics of Material Electronics Research Division, Department of Physics, Institut Teknologi Bandung (Indonesia)

2014-03-24T23:59:59.000Z

146

Characteristics of Hf-silicate thin films synthesized by plasma enhanced atomic layer deposition  

SciTech Connect (OSTI)

Hafnium silicate films were grown by alternating the deposition cycles of hafnium oxide and silicon oxide using a plasma enhanced atomic layer deposition process. The as-deposited and 900 deg. C annealed hafnium silicate films were determined to be amorphous using grazing incidence x-ray diffraction. This suggested that the formation of hafnium silicate suppressed the crystallization of HfO{sub 2} at high temperatures. The dielectric constants increased from {approx}5 to {approx}17 as the hafnium content increased from 9 to 17 at. % in the hafnium silicate films. The leakage currents through the Hf-rich Hf-silicate films were two to three orders of magnitude lower than that of SiO{sub 2} with the same equivalent oxide thickness in the range of 1.6-2.3 nm. The estimated band gap of Hf-silicate films from the O 1s plasma loss spectra increased with the increasing Si content due to the higher band gap of SiO{sub 2} than that of HfO{sub 2}.

Liu Jiurong; Martin, Ryan M.; Chang, Jane P. [Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, California 90095 (United States)

2008-09-15T23:59:59.000Z

147

Mechanical Properties of Aluminum Fluoride Glass Fibers James Colaizzi, M. John Matthewson, Tariq Iqbal, and Mahmoud R. Shahriari  

E-Print Network [OSTI]

#12;Mechanical Properties of Aluminum Fluoride Glass Fibers James Colaizzi, M. John Matthewson solutions of various pH values on the mechanical properties of polymer coated optical fibers of an aluminum to failure of the fiber. In static fatigue, the time to failure of the aluminum fluoride-based fibers

Matthewson, M. John

148

Ion assisted deposition of optical and protective coatings for heavy metal fluoride glass  

SciTech Connect (OSTI)

Heavy metal fluoride glass materials are attractive for optical applications in the near UV through IR wavelength regions. However, many compositions are relatively soft and hygroscopic and possess low softening temperature (250--300/sup 0/C). We have applied ion assisted deposition (IAD) techniques to deposit MgF/sub 2/, SiO/sub 2/, and Al/sub 2/O/sub 3//SiO/sub 2/ thin film structures on fluoride glass substrates at ambient substrate temperature (--100/sup 0/C). The coatings deposited using IAD improve the environmental durability of the fluoride glass and appear to have reasonably good optical characteristics; without application of IAD, the deposited coatings are not durable and have poor adhesion.

McNally, J.J.; Al-Jumaily, G.A.; McNeil, J.R.

1986-06-15T23:59:59.000Z

149

Band offsets in HfO{sub 2}/InGaZnO{sub 4} heterojunctions  

SciTech Connect (OSTI)

The valence band discontinuity ({Delta}E{sub V}) of sputter deposited HfO{sub 2}/InZnGaO{sub 4} (IGZO) heterostructures was obtained from x-ray photoelectron spectroscopy measurements. The HfO{sub 2} exhibited a bandgap of 6.07 eV from absorption measurements. A value of {Delta}E{sub V} = 0.48 {+-} 0.025 eV was obtained by using the Ga 2p{sub 3/2}, Zn 2p{sub 3/2}, and In 3d{sub 5/2} energy levels as references. This implies a conduction band offset {Delta}E{sub C} of 2.39 eV in HfO{sub 2}/InGaZnO{sub 4} heterostructures and a nested interface band alignment.

Cho, Hyun [Department of Nanomechatronics Engineering, Pusan National University, Gyeongnam 627-706 (Korea, Republic of); Douglas, E. A.; Gila, B. P.; Craciun, V.; Lambers, E. S.; Pearton, S. J. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Ren Fan [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States)

2012-01-02T23:59:59.000Z

150

Ge doped HfO{sub 2} thin films investigated by x-ray absorption spectroscopy  

SciTech Connect (OSTI)

The stability of the tetragonal phase of Ge doped HfO{sub 2} thin films on Si(100) was investigated. Hf(Ge)O{sub 2} films with Ge atomic concentrations varying from 0% to 15% were deposited by remote plasma chemical vapor deposition. The atomic structure on the oxide after rapid thermal annealing was investigated by x-ray absorption spectroscopy of the O and Ge K edges and by Rutherford backscattering spectrometry. The authors found that Ge concentrations as low as 5 at. % effectively stabilize the tetragonal phase of 5 nm thick Hf(Ge)O{sub 2} on Si and that higher concentrations are not stable to rapid thermal annealing at temperatures above 750 deg. C.

Miotti, Leonardo; Bastos, Karen P.; Lucovsky, Gerald; Radtke, Claudio; Nordlund, Dennis [Department of Physics, North Carolina State University, Box 8202, Raleigh, North Carolina 27695-8202 (United States); Instituto de Quimica, Universidade Federal do Rio Grande do Sul, 91509-900 Porto Alegre (Brazil); Stanford Synchrotron Radiation Lightsource, Menlo Park, California 94025 (United States)

2010-07-15T23:59:59.000Z

151

On the K{sup {pi}} = 0{sup +} rotational bands in the {sup 178}Hf nucleus  

SciTech Connect (OSTI)

The results obtained by studying the angular distributions of gamma rays with respect to the neutron-beam axis in the reaction {sup 178}Hf(n, n'{gamma}) involving the deexcitation of the K{sup {pi}} = 0{sup +} rotational bands of {sup 178}Hf are presented.New information about themultipole-mixing parameter {delta} in gamma transitions from the levels of these bands is obtained. The K{sup {pi}} = 0{sub 4}{sup +} band is constructed anew. The relationship between the parameter {delta} for the (2{sup +}0{sub n}-2{sup +}0{sub 1}) gamma transition and the energy gap {Delta}{sub n} = E{sub lev}(2{sup +}0{sub n}) - E{sub lev}(0{sup +}0{sub n}), on one hand, and the quasiparticle structure of the rotational band, on the other hand, is discussed for {sup 178}Hf on the basis of the quasiparticle-phonon model.

Govor, L. I.; Demidov, A. M.; Kurkin, V. A., E-mail: kurkin@polyn.kiae.su; Mikhailov, I. V. [Russian Research Centre Kurchatov Institute (Russian Federation)

2010-07-15T23:59:59.000Z

152

Numerical investigation of mid-infrared Raman soliton source generation in endless single mode fluoride fibers  

SciTech Connect (OSTI)

We numerically investigate Raman soliton generation in a fluoride photonic crystal fiber (PCF) pumped by 1.93 ?m femtosecond fiber lasers in order to get widely tunable laser source in the mid-infrared region. The simulated results show that a continuously tunable range (1.93???3.95??m) over 2000?nm is achieved in 1-m-long fluoride PCF pumped by a 1.93??m femtosecond fiber laser with a pulse width of 200 fs. The power conversion efficiency is also calculated and the maximum efficiency can be up to 84.27%.

Liu, Lai; Qin, Guan-Shi, E-mail: qings@jlu.edu.cn; Tian, Qi-jun; Zhao, Dan; Qin, Wei-Ping, E-mail: wpqin@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China)

2014-04-28T23:59:59.000Z

153

Spatially-resolved EELS and EDS Analysis of HfOxNy Gate Dielectrics Deposited by MOCVD using [(C2H5)2N]4Hf with NO and O2  

E-Print Network [OSTI]

-resolved electron energy loss spectroscopy (EELS) and energy-dispersive spectrometry (EDS). HfOxNy gate dielectrics a replacement for SiO2 as the gate dielectric material. HfO2 is a promising candidate due to its high dielectric constant its stability on Si. However, crystallization temperatures of less than 500 °C and high impurity

Ng, Wai Tung

154

anhydrous hydrogen fluoride: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

effect of Hydrogen Booster System on exhaust gases emissions of an internal combustion engine. The hydrogen booster produces hydrogen and oxygen using six water fuel cells and...

155

Optical spectroscopic study of the SiN/HfO{sub 2} interfacial formation during rf sputtering of HfO{sub 2}  

SciTech Connect (OSTI)

High-k stacks formed by chemical-vapor-deposited SiN and high-pressure sputtered HfO{sub 2} in either O{sub 2} or Ar atmosphere have been studied. The introduction of a SiN layer is proposed to prevent the uncontrollable SiO{sub 2} growth while sputtering. The formation of Si-O bonds after the sputtering of the HfO{sub 2} film in O{sub 2} atmosphere was observed by infrared spectroscopy. Optical diagnosis of the plasma demonstrated a high density of O radicals in the system when working with O{sub 2}. The small radius and high reactivity of these O radicals are the source of the SiN oxidation. However, the structure of the SiN film is preserved during Ar sputtering.

Toledano-Luque, M.; Lucia, M. L.; Prado, A. del; San Andres, E.; Martil, I.; Gonzalez-Diaz, G. [Departamento de Fisica Aplicada III, Universidad Complutense de Madrid, Ciudad Universitaria, E-28040 Madrid (Spain)

2007-11-05T23:59:59.000Z

156

Two-step behavior of initial oxidation at HfO{sub 2}/Si interface  

SciTech Connect (OSTI)

In situ x-ray photoelectron spectroscopy revealed that initial Si oxidation at the HfO{sub 2}/Si(001) interface in O{sub 2} proceeds in a two-step manner with an initial slow stage followed by a fast one. This transition in the oxidation process is most likely caused by crystallization of the HfO{sub 2} film. The first stage at 400-600 deg. C exhibited postdeposition annealing conditions suitable for suppressing the interfacial Si oxide in a monolayer region.

Miyata, Noriyuki [MIRAI, Advanced Semiconductor Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8562 (Japan)

2006-09-04T23:59:59.000Z

157

Triaxial strongly deformed bands in {sup 164}Hf and the effect of elevated yrast line  

SciTech Connect (OSTI)

Two exotic rotational bands have been identified in {sup 164}Hf and linked to known states. They are interpreted as being associated with the calculated triaxial strongly deformed (TSD) potential energy minimum. The bands are substantially stronger and are located at much lower spins than the previously discovered TSD bands in {sup 168}Hf. In addition to the proton and neutron shell gaps at large trixiality, it was proposed that the relative excitation energy of TSD bands above the yrast line plays an important role in the population of TSD bands.

Ma Wenchao [Department of Physics, Mississippi State University, Mississippi State, MS 39762 (United States)

2012-10-20T23:59:59.000Z

158

High-power ELF radiation generated by modulated HF heating of the ionosphere can cause Earthquakes, Cyclones and localized heating  

E-Print Network [OSTI]

High-power ELF radiation generated by modulated HF heating of the ionosphere can cause Earthquakes, the HAARP heater is the most powerful ionospheric heater, with 3.6GW of effective power using HF heating, Cyclones and localized heating Fran De Aquino Maranhao State University, Physics Department, S

Paris-Sud XI, Université de

159

Trapping in deep defects under substrate hot electron stress in TiN/Hf-silicate based gate stacks  

E-Print Network [OSTI]

Trapping in deep defects under substrate hot electron stress in TiN/Hf-silicate based gate stacks N. Zaslavsky Abstract Substrate hot electron stress was applied on n+ -ringed n-channel MOS capacitors with TiN/Hf-silicate. Introduction Hafnium silicate based high-j gate dielectrics have been put forth as the leading candidates

Misra, Durgamadhab "Durga"

160

Photoemission study of energy-band alignment for RuO{sub x}/HfO{sub 2}/Si system  

SciTech Connect (OSTI)

Conductive oxides RuO{sub x} as alternative electrode on high-{kappa} HfO{sub 2} gate dielectric have been fabricated by ultrahigh-vacuum sputtering and subsequently oxidized using oxygen plasma. The energy-band alignment for the RuO{sub x}/HfO{sub 2}/Si system and the oxidation-state dependence of barrier height for RuO{sub x} contacting to HfO{sub 2} dielectrics has been analyzed by x-ray photoemission spectroscopy. The valence- and conduction-band offsets of HfO{sub 2}/Si are determined to be 3.05{+-}0.1 and 1.48{+-}0.1 eV, respectively. The barrier heights for the RuO{sub x} contacting to HfO{sub 2} are oxidation-state dependent, in the range of 1.95-2.73 eV.

Li, Q.; Wang, S.J.; Li, K.B.; Huan, A.C.H.; Chai, J.W.; Pan, J.S.; Ong, C.K. [Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602 (Singapore); Data Storage Institute, DSI Building, 5 Engineering Drive 1, Singapore 117608 (Singapore); Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602, Singapore and Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602 (Singapore); Department of Physics, National University of Singapore, Singapore 117542 (Singapore)

2004-12-20T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Low-temperature method for enhancing sputter-deposited HfO{sub 2} films with complete oxidization  

SciTech Connect (OSTI)

A low-temperature method, supercritical CO{sub 2} fluid (SCF) technology, is proposed to improve the dielectric properties of ultrathin hafnium oxide (HfO{sub 2}) film at 150 deg. C without significant formation of parasitic oxide at the interface between HfO{sub 2} and Si substrate. In this research, the HfO{sub 2} films were deposited by dc sputter at room temperature and post-treated by SCF which is mixed with 5 vol % propyl alcohol and 5 vol % H{sub 2}O. From high-resolution transmission electron microscopy image, the interfacial oxide of SCF-treated HfO{sub 2} film is only 5 A ring thick. Additionally, the enhancements in the qualities of sputter-deposited HfO{sub 2} film after SCF process are exhibited by x-ray photoelectron spectroscopy and capacitance-voltage (C-V) measurement.

Tsai, C.-T.; Chang, T.-C.; Liu, P.-T.; Yang, P.-Y.; Kuo, Y.-C.; Kin, K.-T.; Chang, P.-L.; Huang, F.-S. [Institute of Electronics Engineering, National Tsing Hua University, HsinChu 300, Taiwan (China); Department of Physics and Institute of Electro-Optical Engineering, Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University, 70 Lien-Hai Road, Kaohsiung 804, Taiwan (China); Department of Photonics and Display Institute, National Chiao Tung University, 1001 Ta-Hsueh Rd., HsinChu 300, Taiwan (China); Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu 300, Taiwan (China); Institute of Electronics Engineering, National Tsing Hua University, HsinChu 300, Taiwan (China)

2007-07-02T23:59:59.000Z

162

Compatibility of Inconel 617 alloy with eutectic fluoride salts at high temperatures  

SciTech Connect (OSTI)

Thermal Energy Storage (TES) capsules made of Inconel 617 alloy were filled with high purity eutectic fluoride salts and thermally cycled at eutectic temperature [plus minus]100 K for a period of up to 50,000 hours. The containment life performance characteristics with fluoride salts were examined. The depletion of Al and Cr near the inner edges was found. Atomic Absorption Spectroscopy revealed that both Al and Cr were dissolved in the fluoride salts at high temperatures. The changes in melting temperature and heat of fusion of fluoride salts during thermal cycling were measured with Thermal Differential Analysis. A modified diffusion equation for a one-dimensional semi-infinite bar was applied to the depletion of Al on the interior surfaces of the containers. Good agreement was obtained between the analysis and the measured concentration profiles. The present study suggests that the corrosion was a diffusion controlled process and an expected lifetime of 5--7 years is reasonable and predictable based upon the limited diffusion processes.

Luo, A.; Jacobson, D.L. (Department of Chemical, Bio Materials Engineering, Arizona State University, Tempe, Arizona 85287-6006 (United States)); Ponnappan, R. (Universal Energy Systems, Inc., 4401 Dayton-Xenia Road, Dayton, Ohio 45432 (United States))

1993-01-10T23:59:59.000Z

163

Primary aluminum: statistical analysis of potline fluoride emissions and alternate sampling frequency. Final report  

SciTech Connect (OSTI)

Statistical analyses were performed on 4 years of fluoride emissions data from a primary aluminum reduction plant. These analyses were used to develop formulae and procedures for use by regulatory agencies in determining alternate sampling frequencies for secondary (roof monitor) emissions testing on a case-by-case basis. Monitoring procedures for ensuring compliance even with a reduced test frequency are also addressed.

Not Available

1986-10-01T23:59:59.000Z

164

Conformational Properties of Poly(vinylidene fluoride). A Quantum Chemistry Study of Model Compounds  

E-Print Network [OSTI]

Conformational Properties of Poly(vinylidene fluoride). A Quantum Chemistry Study of Model of the conformers of HFH resembling crystalline polymorphs of PVDF, indicating that intermolecular interactions unfavorable second-order interactions between fluorine atoms occur in -CH2- centered t+t+ sequences and

Utah, University of

165

Radiolytic Effects on Fluoride Impurities in a U{sub 3}O{sub 8} Matrix  

SciTech Connect (OSTI)

The safe handling and storage of radioactive materials require an understanding of the effects of radiolysis on those materials. Radiolysis may result in the production of gases (e.g., corrosives) or pressures that are deleterious to storage containers. A study has been performed to address these concerns as they relate to the radiolysis of residual fluoride compounds in uranium oxides.

Icenhour, A.S.

2000-05-01T23:59:59.000Z

166

PILOT-SCALE REMOVAL OF FLUORIDE FROM LEGACY PLUTONIUM MATERIALS USING VACUUM SALT DISTILLATION  

SciTech Connect (OSTI)

Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and HB-Line designed, developed, tested, and successfully deployed a system for the distillation of chloride salts. In 2011, SRNL adapted the technology for the removal of fluoride from fluoride-bearing salts. The method involved an in situ reaction between potassium hydroxide (KOH) and the fluoride salt to yield potassium fluoride (KF) and the corresponding oxide. The KF and excess KOH can be distilled below 1000{deg}C using vacuum salt distillation (VSD). The apparatus for vacuum distillation contains a zone heated by a furnace and a zone actively cooled using either recirculated water or compressed air. During a vacuum distillation operation, a sample boat containing the feed material is placed into the apparatus while it is cool, and the system is sealed. The system is evacuated using a vacuum pump. Once a sufficient vacuum is attaned, heating begins. Volatile salts distill from the heated zone to the cooled zone where they condense, leaving behind the non-volatile material in the feed boat. Studies discussed in this report were performed involving the use of non-radioactive simulants in small-scale and pilot-scale systems as well as radioactive testing of a small-scale system with plutonium-bearing materials. Aspects of interest include removable liner design considerations, boat materials, in-line moisture absorption, and salt deposition.

Pierce, R. A.; Pak, D. J.

2012-09-11T23:59:59.000Z

167

Selective reflection spectroscopy of a vapour at a calcium fluoride interface  

E-Print Network [OSTI]

Selective reflection spectroscopy of a vapour at a calcium fluoride interface T. Passerat de Silans materials exhibit surface resonances located in the thermal infrared. This makes them interesting to search for a fundamental temperature dependence of the atom-surface interaction, originating in the near-field thermal

Paris-Sud XI, Université de

168

Neutron diffraction studies of antiferromagnetism in manganous fluoride and some isomorphous compounds  

E-Print Network [OSTI]

FLUORIDE AND SOME ISOMORPHOUS COMPOUNDS Major Subject: Physics 1 2 11 16 16 18 27 29 31 38 38 54 58 63 67 75 77 TABLE OF CONTENTS CHAPTER I. INTRODUCTION . . . ......................... II. MAGNETIC PROPERTY CONSIDERATIONS............... Ill. RELATIONS FOE THE MAGNETIC SCATTERING OF NEUTRONS IV. APPARATUS AND PROCEDURE................... . A. The Neutron Spectrometer.............. B. The Low Temperature Cryostat.......... C. Lov Temperature Coolants. . . . . . . . . D. Sample...

Erickson, Richard Ames

1952-01-01T23:59:59.000Z

169

Nuclear spin relaxation in a vinylidene fluoride and trifluoroethylene copolymer (70/30).  

E-Print Network [OSTI]

583 Nuclear spin relaxation in a vinylidene fluoride and trifluoroethylene copolymer (70/30). II orientations dans les chaînes. Abstract. 2014 Measurements of the hydrogen and fluorine nuclear spin-lattice relaxation times T1 from 6 to 300 MHz and T103C1 from 3 to 100 kHz have been performed at different

Boyer, Edmond

170

Meridian-scanning photometer, coherent HF radar, and magnetometer observations of the cusp: a case study  

E-Print Network [OSTI]

the transport of mass, energy, and momentum from the solar wind into the near-Earth environment, is facilitated with the CUTLASS Finland coherent HF radar, a meridian-scanning photometer located at Ny AÃ? lesund, Svalbard on the scale of minutes, and which are believed to be related to the dynamic nature of energy and momentum

Paris-Sud XI, Université de

171

Metal-gate-induced reduction of the interfacial layer in Hf oxide gate stacks  

SciTech Connect (OSTI)

The properties of high-{kappa} metal oxide gate stacks are often determined in the final processing steps following dielectric deposition. We report here results from medium energy ion scattering and x-ray photoelectron spectroscopy studies of oxygen and silicon diffusion and interfacial layer reactions in multilayer gate stacks. Our results show that Ti metallization of HfO{sub 2}/SiO{sub 2}/Si stacks reduces the SiO{sub 2} interlayer and (to a more limited extent) the HfO{sub 2} layer. We find that Si atoms initially present in the interfacial SiO{sub 2} layer incorporate into the bottom of the high-{kappa} layer. Some evidence for Ti-Si interdiffusion through the high-{kappa} film in the presence of a Ti gate in the crystalline HfO{sub 2} films is also reported. This diffusion is likely to be related to defects in crystalline HfO{sub 2} films, such as grain boundaries. High-resolution transmission electron microscopy and corresponding electron energy loss spectroscopy scans show aggressive Ti-Si intermixing and oxygen diffusion to the outermost Ti layer, given high enough annealing temperature. Thermodynamic calculations show that the driving forces exist for some of the observed diffusion processes.

Goncharova, L. V.; Dalponte, M.; Gustafsson, T.; Celik, O.; Garfunkel, E.; Lysaght, P. S.; Bersuker, G. [Department of Physics and Astronomy, and Laboratory for Surface Modification, Rutgers University, 136 Frelinghuysen Rd., Piscataway, New Jersey 08854 (United States); Department of Chemistry and Chemical Biology, and Laboratory for Surface Modification, Rutgers University, 610 Taylor Rd., Piscataway, New Jersey 08854 (United States); SEMATECH, 2705 Montopolis Dr., Austin, Texas 78741 (United States)

2007-03-15T23:59:59.000Z

172

Scanning tunneling microscopy study of nitrogen incorporated HfO{sub 2}  

SciTech Connect (OSTI)

The impact of nitrogen incorporation on the physical and electrical characteristics of the HfO{sub 2} is examined. X-ray photoelectron spectroscopy shows that nitrogen can be incorporated into the HfO{sub 2} via a two-step thermal anneal--first in ultrahigh vacuum (UHV) and subsequently in N{sub 2}. Following the N{sub 2} anneal, scanning tunneling microscopy in UHV reveals a marked reduction in the low-voltage leakage current under gate injection biasing. From band theory and existing first-principles simulation results, one may consistently attribute this improvement to the passivation of oxygen vacancies in the HfO{sub 2} by nitrogen. Improvement in the breakdown strength of the HfO{sub 2} subjected to ramp-voltage stress (substrate injection) is also observed after the N{sub 2} anneal. The local current-voltage curves acquired concurrently during the ramp-voltage stress exhibit 'space-charge limited conduction', which implies that the observed improvement in breakdown strength may be related to a limitation of the current flow through the gate stack in the high stress voltage regime.

Ong, Y. C.; Ang, D. S.; Pey, K. L.; Li, X. [Nanyang Technological University, School of Electrical and Electronic Engineering, Nanyang Avenue, Singapore 639798 (Singapore); O'Shea, S. J.; Wang, S. J. [Institute of Materials Research and Engineering, A-STAR - Agency for Science, Technology and Research, 3 Research Link, Singapore 11760 (Singapore); Tung, C. H. [Institute of Microelectronics, A-STAR - Agency for Science, Technology and Research, 11 Science Park Road, Singapore Science Park II, Singapore 117685 (Singapore)

2008-09-15T23:59:59.000Z

173

ACCEPTED MANUSCRIPT The behaviour of Rare-Earth Elements, Zr and Hf during biologically-mediated  

E-Print Network [OSTI]

ACCEPTED MANUSCRIPT ACCEPTED MANUSCRIPT 1 The behaviour of Rare-Earth Elements, Zr and Hf during.a,b* , Cangemi M.a , Brusca L.c , Madonia P.c , Saiano F.d , Zuddas P.e a) Department of Earth and Marine at the solid-liquid interface influencing the distribution of trace elements onto microbial surfaces. Since

174

Investigation of HF plasma turbulence excitation and dissipation in the vicinity of 5th  

E-Print Network [OSTI]

of stimulated electromagnetic emission (SEE) of the ionosphere pumped by powerful HF radio waves are presented, Uppsala Division, SE-751 21 Uppsala, Sweden Experimental results on development and relaxation times after PW turn off d 0.7­1.0 ms are 2­4 times faster than collisional ones for the Langmuir waves

175

Oxygen diffusion and reactions in Hf-based dielectrics L. V. Goncharova,a  

E-Print Network [OSTI]

Oxygen diffusion and reactions in Hf-based dielectrics L. V. Goncharova,a M. Dalponte, D. G Oxygen transport in and reactions with thin hafnium oxide and hafnium silicate films have been. The exchange rate is faster for pure hafnium oxides than for silicates. The amount of exchanged oxygen

Gustafsson, Torgny

176

HF radar in French Mediterranean Sea: an element of MOOSE Mediterranean Ocean Observing System on Environment  

E-Print Network [OSTI]

Sea in the context of climate change and anthropogenic pressure and to supply and maintain longHF radar in French Mediterranean Sea: an element of MOOSE Mediterranean Ocean Observing System , Pascal Guterman2 , Karim Bernardet2 1 Mediterranean Institute of Oceanography (MIO, UM 110, USTV

Boyer, Edmond

177

Elevated temperature ablation resistance of HfC particle-reinforced tungsten composites  

E-Print Network [OSTI]

C­W was attributed to the low thermal conductivity, high oxidation resistance, and high melting point of the Hf melting points (e.g., 3440 °C for W), high moduli of elasticity, good thermal shock resistances, and good torch was used to ablate the samples at high temperature. Ablation resistance improved with an in

Hong, Soon Hyung

178

Method for producing nanostructured metal-oxides  

DOE Patents [OSTI]

A synthetic route for producing nanostructure metal-oxide-based materials using sol-gel processing. This procedure employs the use of stable and inexpensive hydrated-metal inorganic salts and environmentally friendly solvents such as water and ethanol. The synthesis involves the dissolution of the metal salt in a solvent followed by the addition of a proton scavenger, which induces gel formation in a timely manner. Both critical point (supercritical extraction) and atmospheric (low temperature evaporation) drying may be employed to produce monolithic aerogels and xerogels, respectively. Using this method synthesis of metal-oxide nanostructured materials have been carried out using inorganic salts, such as of Fe3+, Cr3+, Al3+, Ga3+, In3+, Hf4+, Sn4+, Zr4+, Nb5+, W6+, Pr3+, Er3+, Nd3+, Ce3+, U3+ and Y3+. The process is general and nanostructured metal-oxides from the following elements of the periodic table can be made: Groups 2 through 13, part of Group 14 (germanium, tin, lead), part of Group 15 (antimony, bismuth), part of Group 16 (polonium), and the lanthanides and actinides. The sol-gel processing allows for the addition of insoluble materials (e.g., metals or polymers) to the viscous sol, just before gelation, to produce a uniformly distributed nanocomposites upon gelation. As an example, energetic nanocomposites of FexOy gel with distributed Al metal are readily made. The compositions are stable, safe, and can be readily ignited to thermitic reaction.

Tillotson, Thomas M.; Simpson, Randall L.; Hrubesh, Lawrence W.; Gash, Alexander

2006-01-17T23:59:59.000Z

179

Control of silicidation in HfO2/Si,,100... interfaces Deok-Yong Cho, Kee-Shik Park, B.-H. Choi,a  

E-Print Network [OSTI]

like nitrogen.6,7 Among these, Hf-silicide is probably most detrimental since it is metallic and degrades the capacitor performance. Metal- lic Hf-silicide formation has been reported in the interfaceControl of silicidation in HfO2/Si,,100... interfaces Deok-Yong Cho, Kee-Shik Park, B.-H. Choi

Oh, Se-Jung

180

An Experimental Test Facility to Support Development of the Fluoride Salt Cooled High Temperature Reactor  

SciTech Connect (OSTI)

The need for high-temperature (greater than 600 C) energy exchange and delivery systems is significantly increasing as the world strives to improve energy efficiency and develop alternatives to petroleum-based fuels. Liquid fluoride salts are one of the few energy transport fluids that have the capability of operating at high temperatures in combination with low system pressures. The Fluoride Salt-Cooled High-Temperature Reactor design uses fluoride salt to remove core heat and interface with a power conversion system. Although a significant amount of experimentation has been performed with these salts, specific aspects of this reactor concept will require experimental confirmation during the development process. The experimental facility described here has been constructed to support the development of the Fluoride Salt Cooled High Temperature Reactor concept. The facility is capable of operating at up to 700 C and incorporates a centrifugal pump to circulate FLiNaK salt through a removable test section. A unique inductive heating technique is used to apply heat to the test section, allowing heat transfer testing to be performed. An air-cooled heat exchanger removes added heat. Supporting loop infrastructure includes a pressure control system; trace heating system; and a complement of instrumentation to measure salt flow, temperatures, and pressures around the loop. The initial experiment is aimed at measuring fluoride salt heat transfer inside a heated pebble bed similar to that used for the core of the pebble bed advanced high-temperature reactor. This document describes the details of the loop design, auxiliary systems used to support the facility, the inductive heating system, and facility capabilities.

Yoder Jr, Graydon L [ORNL] [ORNL; Aaron, Adam M [ORNL] [ORNL; Cunningham, Richard Burns [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK); Fugate, David L [ORNL] [ORNL; Holcomb, David Eugene [ORNL] [ORNL; Kisner, Roger A [ORNL] [ORNL; Peretz, Fred J [ORNL] [ORNL; Robb, Kevin R [ORNL] [ORNL; Wilgen, John B [ORNL] [ORNL; Wilson, Dane F [ORNL] [ORNL

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Nitrogen Doping and Thermal Stability in HfSiOxNy Studied by Photoemission and X-ray Absorption Spectroscopy  

SciTech Connect (OSTI)

We have investigated nitrogen-doping effects into HfSiO{sub x} films on Si and their thermal stability using synchrotron-radiation photoemission and x-ray absorption spectroscopy. N 1s core-level photoemission and N K-edge absorption spectra have revealed that chemical-bonding states of N-Si{sub 3-x}O{sub x} and interstitial N{sub 2}-gas-like features are clearly observed in as-grown HfSiO{sub x}N{sub y} film and they decrease upon ultrahigh vacuum (UHV) annealing due to a thermal instability, which can be related to the device performance. Annealing-temperature dependence in Hf 4f and Si 2p photoemission spectra suggests that the Hf-silicidation temperature is effectively increased by nitrogen doping into the HfSiO{sub x} although the interfacial SiO{sub 2} layer is selectively reduced. No change in valence-band spectra upon UHV annealing suggests that crystallization of the HfSiO{sub x}N{sub y} films is also hindered by nitrogen doping into the HfSiO{sub x}.

Toyoda, Satoshi; Okabayashi, Jun; Takahashi, Haruhiko; Oshima, Masaharu; /Tokyo U.; Lee, Dong-Ick; Sun, Shiyu; sun, Steven; Pianetta, Piero A.; /SLAC, SSRL; Ando, Takashi; Fukuda, Seiichi; /SONY, Atsugi

2005-12-14T23:59:59.000Z

182

A low temperature fabrication of HfO{sub 2} films with supercritical CO{sub 2} fluid treatment  

SciTech Connect (OSTI)

To improve the dielectric properties of sputter-deposited hafnium oxide (HfO{sub 2}) films, the supercritical CO{sub 2} (SCCO{sub 2}) fluid technology is introduced as a low temperature treatment. The ultrathin HfO{sub 2} films were deposited on p-type (100) silicon wafer by dc sputtering at room temperature and subsequently treated with SCCO{sub 2} fluids at 150 deg. C to diminish the traps in the HfO{sub 2} films. After SCCO{sub 2} treatment, the interfacial parasitic oxide between the Si substrate and HfO{sub 2} layer is only about 5 A, and the oxygen content of the HfO{sub 2} films apparently increased. From current-voltage (I-V) and capacitance-voltage (C-V) measurements, the leakage current density of the SCCO{sub 2}-treated HfO{sub 2} films is repressed from 10{sup -2} to 10{sup -7} A/cm{sup 2} at electric field=3 MV/cm due to the reduction of traps in the HfO{sub 2} films. The equivalent oxide thickness also obviously decreased. Besides, the efficiency of terminating traps is relative to the pressure of the SCCO{sub 2} fluids.

Tsai, C.-T.; Huang, F.-S. [Institute of Electronics Engineering, National Tsing Hua University, HsinChu 300, Taiwan (China); Chang, T.-C. [Department of Physics, Center for Nanoscience and Nanotechnology, National Sun Yat-set University, 70 Lien-hai Road, Kaohsiung 804, Taiwan (China); Institute of Electro-Optical Engineering, National Sun Yat-sen University, Kaohsiung 804, Taiwan (China); Kin, K.-T. [Industrial Technology Research Institute-Energy and Environment Research Laboratories, Hsinchu 300, Taiwan (China); Liu, P.-T.; Yang, P.-Y. [Department of Photonics and Display Institute, National Chiao Tung University, Hsinchu 300, Taiwan (China); Weng, C.-F. [Department of Physics, Center for Nanoscience and Nanotechnology, National Sun Yat-set University, 70 Lien-hai Road, Kaohsiung 804, Taiwan (China)

2008-04-01T23:59:59.000Z

183

Effect of Acidulated Phosphate Fluoride Gel on the Prevention of White Spot Lesions in Patients Undergoing Active Orthodontic Treatment  

E-Print Network [OSTI]

Introduction: The purpose of this study was to evaluate the effect of 1.23% acidulated phosphate fluoride (APF) gel on white spot lesion (WSL) formation utilizing a typical orthodontic treatment interval for the applications. Methods...

Hutto Fretty, Corneil Kimberly

2014-05-06T23:59:59.000Z

184

Investigation and design of a secure, transportable fluoride-salt-cooled high-temperature reactor (TFHR) for isolated locations  

E-Print Network [OSTI]

In this work we describe a preliminary design for a transportable fluoride salt cooled high temperature reactor (TFHR) intended for use as a variable output heat and electricity source for off-grid locations. The goals of ...

Macdonald, Ruaridh (Ruaridh R.)

2014-01-01T23:59:59.000Z

185

Impact of pH on the removal of fluoride, nitrate and boron by nanofiltration/reverse osmosis   

E-Print Network [OSTI]

The objective of this study was to evaluate the impact of pH on boron, fluoride, and nitrate retention by comparing modelled speciation predictions with retention using six different nanofiltration (NF) and reverse osmosis ...

Richards, Laura A.; Vuachère, Marion; Schäfer, Andrea

2010-01-01T23:59:59.000Z

186

Tritium production analysis and management strategies for a Fluoride-salt-cooled high-temperature test reactor (FHTR)  

E-Print Network [OSTI]

The Fluoride-salt-cooled High-temperature Test Reactor (FHTR) is a test reactor concept that aims to demonstrate the neutronics, thermal-hydraulics, materials, tritium management, and to address other reactor operational ...

Rodriguez, Judy N

2013-01-01T23:59:59.000Z

187

Preventing fuel failure for a beyond design basis accident in a fluoride salt cooled high temperature reactor  

E-Print Network [OSTI]

The fluoride salt-cooled high-temperature reactor (FHR) combines high-temperature coated-particle fuel with a high-temperature salt coolant for a reactor with unique market and safety characteristics. This combination can ...

Minck, Matthew J. (Matthew Joseph)

2013-01-01T23:59:59.000Z

188

APPLICATION OF VACUUM SALT DISTILLATION TECHNOLOGY FOR THE REMOVAL OF FLUORIDE  

SciTech Connect (OSTI)

Vacuum distillation of chloride salts from plutonium oxide (PuO{sub 2}) and simulant PuO{sub 2} has been previously demonstrated at Department of Energy (DOE) sites using kilogram quantities of chloride salt. The apparatus for vacuum distillation contains a zone heated using a furnace and a zone actively cooled using either recirculated water or compressed air. During a vacuum distillation operation, a sample boat containing the feed material is placed into the apparatus while it is cool, and the system is sealed. The system is evacuated using a vacuum pump. Once a sufficient vacuum is attained, heating begins. Volatile salts distill from the heated zone to the cooled zone where they condense, leaving behind the non-volatile materials in the feed boat. The application of vacuum salt distillation (VSD) is of interest to the HB-Line Facility and the MOX Fuel Fabrication Facility (MFFF) at the Savannah River Site (SRS). Both facilities are involved in efforts to disposition excess fissile materials. Many of these materials contain chloride and fluoride salt concentrations which make them unsuitable for dissolution without prior removal of the chloride and fluoride salts. Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and HB-Line designed, developed, tested, and successfully deployed a system for the distillation of chloride salts. Subsequent efforts are attempting to adapt the technology for the removal of fluoride. Fluoride salts of interest are less-volatile than the corresponding chloride salts. Consequently, an alternate approach is required for the removal of fluoride without significantly increasing the operating temperature. HB-Line Engineering requested SRNL to evaluate and demonstrate the feasibility of an alternate approach using both non-radioactive simulants and plutonium-bearing materials. Whereas the earlier developments targeted the removal of sodium chloride (NaCl) and potassium chloride (KCl), the current activities are concerned with the removal of the halide ions associated with plutonium trifluoride (PuF{sub 3}), plutonium tetrafluoride (PuF{sub 4}), calcium fluoride (CaF{sub 2}), and calcium chloride (CaCl{sub 2}). This report discusses non-radioactive testing of small-scale and pilot-scale systems and radioactive testing of a small-scale system. Experiments focused on demonstrating the chemistry for halide removal and addressing the primary engineering questions associated with a change in the process chemistry.

Pierce, R.; Pak, D.

2011-08-10T23:59:59.000Z

189

Coal markets squeeze producers  

SciTech Connect (OSTI)

Supply/demand fundamentals seem poised to keep prices of competing fossil fuels high, which could cushion coal prices, but increased mining and transportation costs may squeeze producer profits. Are markets ready for more volatility?

Ryan, M.

2005-12-01T23:59:59.000Z

190

Report on Produced Water  

Office of Scientific and Technical Information (OSTI)

of the pond, as well as the quality of the produced water. In semiarid regions, hot, dry air moving from a land surface will result in high evaporation rates for smaller ponds. As...

191

Variable dimensionality in the uranium fluoride/2-methyl-piperazine system: Synthesis and structures of UFO-5, -6, and -7; Zero-, one-, and two-dimensional materials with unprecedented topologies  

SciTech Connect (OSTI)

Recently, low temperature (T < 300 C) hydrothermal reactions of inorganic precursors in the presence of organic cations have proven highly productive for the synthesis of novel solid-state materials. Interest in these materials is driven by the astonishingly diverse range of structures produced, as well as by their many potential materials chemistry applications. This report describes the high yield, phase pure hydrothermal syntheses of three new uranium fluoride phases with unprecedented structure types. Through the systematic control of the synthesis conditions the authors have successfully controlled the architecture and dimensionality of the phase formed and selectively synthesized novel zero-, one-, and two-dimensional materials.

Francis, R.J.; Halasyamani, P.S.; Bee, J.S.; O'Hare, D.

1999-02-24T23:59:59.000Z

192

Specific interaction of fluoride ions with aluminum and gallium solvates in an ethylene glycol solutions  

SciTech Connect (OSTI)

The interaction of aluminum chloride and gallium chloride with KF in ethylene glycol solutions with F:M/sup 3 +/ mole ratios approximately equal to 2 includes a step involving the formation of fluorine-containing species, in which the fluoride ions are held in the outer sphere of ethylene glycol solvates of aluminum and gallium. Complexes based on hexacoordinate solvates predominate in the solutions of aluminum, while in the case of gallium, in contrast to aluminum, the coexistence of tetra- and hexacoordinate complexes is characteristic. The configurational equilibrium in the solutions of gallium is one of the causes of the structurization of the solutions, i.e., polymerization due to the formation of H bonds between the fluoride ions and the coordinated ethylene glycol molecules.

Petrosyants, S.P.; Tsabel', E.R.; Buslaev, Yu.A.

1986-01-01T23:59:59.000Z

193

Effect of fulvic acid on the kinetics of aluminum fluoride complexation in acidic waters  

SciTech Connect (OSTI)

Both fluoride ion and fulvic acid are important aluminum binding ligands present in soil and surface waters. As such they play a role in the speciation and toxicity of natural waters that have increased aluminum concentration due to acid precipitation. We report here a kinetic study of aluminum complexation in the presence of both of these naturally occurring ligands. An overall mechanism has been identified and rate constants have been obtained for several of the reactions involved. We find that an a priori model of the two ligands in competition for aluminum is incorrect. In fact, the rate of fluoride ion consumption is increased by the presence of fulvic acid. Evidence is presented that this effect is due to several equilibria, some of which involve mixed-ligand species. The important equilibria in this three-component system are identified and discussed, as are aluminum speciation and toxicity in acidic waters.

Plankey, B.J.; Patterson, H.H.

1988-12-01T23:59:59.000Z

194

Nuclear quantum effects in water exchange around lithium and fluoride ions  

E-Print Network [OSTI]

We employ classical and ring polymer molecular dynamics simulations to study the effect of nuclear quantum fluctuations on the structure and the water exchange dynamics of aqueous solutions of lithium and fluoride ions. While we obtain reasonably good agreement with experimental data for solutions of lithium by augmenting the Coulombic interactions between the ion and the water molecules with a standard Lennard-Jones ion-oxygen potential, the same is not true for solutions of fluoride, for which we find that a potential with a softer repulsive wall gives much better agreement. A small degree of destabilization of the first hydration shell is found in quantum simulations of both ions when compared with classical simulations, with the shell becoming less sharply defined and the mean residence time of the water molecules in the shell decreasing. In line with these modest differences, we find that the mechanisms of the exchange processes are unaffected by quantization, so a classical description of these reaction...

Wilkins, David M; Dang, Liem X

2015-01-01T23:59:59.000Z

195

Electronic properties of InP (001)/HfO{sub 2} (001) interface: Band offsets and oxygen dependence  

SciTech Connect (OSTI)

Using ab-initio methods, atomic structures and electronic properties of InP (001)/HfO{sub 2} (001) interface are studied within the framework of density functional theory. We examine the InP/HfO{sub 2} model interface electronic structures under varying oxidation conditions. The effects of indium and phosphorous concentrations on interfacial bonding, defect states, band offsets, and the thermodynamic stability at the interface are also investigated. The origin of interfacial gap states in InP (001)/HfO{sub 2} (001) interface are proposed, mainly from the P-rich oxides, which is validated by our experimental work. This highlights the importance of surface passivation prior to high-? deposition based on the in situ spectroscopic results of atomic layer deposition of HfO{sub 2} on InP.

KC, Santosh; Dong, Hong; Longo, Roberto C.; Xiong, Ka [Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080 (United States); Wang, Weichao [Department of Electronics and Microelectronics and Tianjin Key Laboratory of Photo-Electronic Thin Film Device and Technology, Nankai University, Tianjin 300071 (China); Wallace, Robert M.; Cho, Kyeongjae, E-mail: kjcho@utdallas.edu [Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080 (United States); Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080 (United States)

2014-01-14T23:59:59.000Z

196

Initial phases in sputter deposited HfO{sub 2}-Al{sub 2}O{sub 3} nanolaminate films  

SciTech Connect (OSTI)

Nanolaminate films of crystalline HfO{sub 2} and amorphous Al{sub 2}O{sub 3} were grown by reactive sputter deposition on unheated fused SiO{sub 2} and the surface oxide of <111> Si. X-ray diffraction showed the amount of monoclinic (m) HfO{sub 2} decreased with decreasing HfO{sub 2} layer thickness, consistent with a finite crystal size effect. High resolution transmission electron microscopy of individual crystallites detected tetragonal (t) and orthorhombic (o) HfO{sub 2} as the initial phases formed. Whereas the t{yields}m transition is accomplished by a shear mechanism, we demonstrate the important role of polysynthetic twinning for the o{yields}m transition.

Hoppe, E. E.; Aita, C. R.; Gajdardziska-Josifovska, M. [Advanced Coatings Experimental Laboratory, University of Wisconsin-Milwaukee, P.O. Box 784, Milwaukee, Wisconsin 53201 (United States); Department of Physics and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States)

2007-11-12T23:59:59.000Z

197

Enhanced electrical characteristics of Au nanoparticles embedded in high-k HfO{sub 2} matrix  

SciTech Connect (OSTI)

We present experimental results for laser-induced Au nanoparticle (NP) embedded in a HfO{sub 2} high-k dielectric matrix. Cross-sectional transmission electron microscopy images showed that the Au NPs of 8 nm in diameter were clearly embedded in HfO{sub 2} matrix. Capacitance-voltage measurements of Pt/HfO{sub 2}/Au NPs/HfO{sub 2} on p-type Si substrate reliably exhibited metal-oxide-semiconductor behavior with a large flatband shift of 4.7 V. In addition, the charge retention time at room temperature was found to exceed 10{sup 5} h. This longer time was attributed to the higher electron barrier height via high work function of the Au NP.

Yang, Jung Yup; Kim, Ju Hyung; Choi, Won Joon; Do, Young Ho; Kim, Chae Ok; Hong, Jin Pyo [New Functional Materials and Devices Laboratory, Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of)

2006-09-15T23:59:59.000Z

198

Shape memory response and microstructural evolution of a severe plastically deformed high temperature shape memory alloy (NiTiHf)  

E-Print Network [OSTI]

NiTiHf alloys have attracted considerable attention as potential high temperature Shape Memory Alloy (SMA) but the instability in transformation temperatures and significant irrecoverable strain during thermal cycling under constant stress remains a...

Simon, Anish Abraham

2006-04-12T23:59:59.000Z

199

EFFECT OF AGING ON THE PHASE TRANSFORMATION AND MECHANICAL BEHAVIOR OF Ti36Ni49Hf15 HIGH  

E-Print Network [OSTI]

and Engineering, Harbin Institute of Technology, Harbin 150001, People's Republic of China (Received August 19 the microstructure, transformation temperature, mechanical properties and shape memory effects (SMEs) for Ti36Ni49Hf

Zheng, Yufeng

200

Human Factors Process Failure Mode and Effects Analysis (HF PFMEA) Application in the Evaluation of Management Risks  

E-Print Network [OSTI]

.3.1. Mechanisms of Prevention ............................................................................................... 11 2.4. Human Factors Process Failure Mode and Effects Analysis (HF PFMEA) ....................... 11 2.5. FMEA Components... ........................................................................................... 15 2.5.5. Risk Priority Number ....................................................................................................... 17 2.6. FMEA Model...

Soguilon, Nenita M.

2009-12-18T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Mode specificity in the HF + OH ? F + H{sub 2}O reaction  

SciTech Connect (OSTI)

Full-dimensional quantum dynamics and quasi-classical trajectory calculations are reported for the title reaction on a recently constructed ab initio based global potential energy surface. Strong mode specificity was found, consistent with the prediction of the sudden vector projection model. Specifically, the HF vibration strongly promotes the reaction while the OH vibration has little effect. Rotational excitations of both reactants slightly enhance the reaction.

Song, Hongwei; Li, Jun; Guo, Hua, E-mail: hguo@unm.edu [Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131 (United States)

2014-10-28T23:59:59.000Z

202

Reactive ion beam etching of HfO{sub 2} film and removal of sidewall redeposition  

SciTech Connect (OSTI)

Comparative studies on ion beam etching (IBE) and reactive ion beam etching (RIBE) of HfO{sub 2} film have been carried out using photoresist as the masking layer. The etching rates of HfO{sub 2} film and photoresist mask in pure Ar and Ar/CHF{sub 3} mixture plasmas were measured as a function of ion energy, plasma composition, and ion beam incident angle. It has been found that the RIBE with Ar/CHF{sub 3} plasma is capable of lowering the threshold energy of ion beam and increasing sputtering yield, compared to the IBE with pure Ar. The redeposition of photoresist sidewall is a major issue, due to the formation of nonvolatile etching products during sputtering of HfO{sub 2} film in both IBE and RIBE. However, the sidewall redeposition can be easily removed in HCl solutions with assistance of ultrasonic wave for RIBE with Ar/CHF{sub 3} plasma. Alternatively, the sidewall redeposition can be eliminated by controlling the slope of photoresist sidewall or combined with ion incident angle.

Wang Xudi; Liu Ying; Xu Xiangdong; Fu Shaojun; Cui Zheng [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026 (China) and School of Mechanical and Automobile Engineering, Hefei University of Technology, Hefei 230009 (China); National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026 (China); Central Microstructure Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom)

2006-07-15T23:59:59.000Z

203

Gate Metal-Induced Diffusion and Interface Reactions in Hf Oxide Films on Si  

SciTech Connect (OSTI)

When metal electrodes are deposited on a high-{kappa} metal-oxide/SiO{sub 2}/Si stack, chemical interactions may occur both at the metal/high-{kappa} and the high-{kappa}/Si interfaces, causing changes in electrical performance. We report here results from medium energy ion scattering (MEIS) and x-ray photoelectron (XPS) studies of oxygen and silicon transport and interfacial layer reactions in multilayer gate stacks. Our results show that Ti deposition on HfO{sub 2}/SiO{sub 2}/Si stacks causes reduction of the SiO{sub 2} interfacial layer and (to a lesser extent) the HfO{sub 2} layer. Silicon atoms initially present in the interfacial SiO{sub 2} layer incorporate into the bottom of the high-{kappa} layer. Some evidence for titanium-silicon interdiffusion through the high-{kappa} film in the presence of a titanium gate in crystalline HfO{sub 2} films is also reported.

Goncharova, Lyudmila V.; Dalponte, Mateus; Celik, Ozgur; Garfunkel, Eric; Gustafsson, Torgny [Departments of Physics and Chemistry, and Laboratory for Surface Modification, Rutgers University, Piscataway, NJ 08854 (United States); Lysaght, Pat S.; Bersuker, Gennadi I. [Sematech, Austin, Texas 78741 (United States)

2007-09-26T23:59:59.000Z

204

Impact of titanium addition on film characteristics of HfO{sub 2} gate dielectrics deposited by atomic layer deposition  

SciTech Connect (OSTI)

The impact of 8-to 45-at. % Ti on physical and electrical characteristics of atomic-layer-deposited and annealed hafnium dioxide was studied using vacuum-ultraviolet spectroscopic ellipsometry, secondary ion mass spectroscopy, transmission electron microscopy, atomic force microscopy, x-ray diffraction, Rutherford backscattering spectroscopy, x-ray photoelectron spectroscopy, and x-ray reflectometry. The role of Ti addition on the electrical performance is investigated using molybdenum (Mo)-gated capacitors. The film density decreases with increasing Ti addition. Ti addition stabilizes the amorphous phase of HfO{sub 2}, resulting in amorphous films as deposited. After a high-temperature annealing, the films transition from an amorphous to a polycrystalline phase. Orthorhombic Hf-Ti-O peaks are detected in polycrystalline films containing 33-at. % or higher Ti content. As Ti content is decreased, monoclinic HfO{sub 2} becomes the predominant microstructure. No TiSi is formed at the dielectric/Si interface, indicating films with good thermal stability. The band gap of Hf-Ti-O was found to be lower than that of HfO{sub 2}. Well-behaved capacitance-voltage and leakage current density-voltage characteristics were obtained for Hf-Ti-O. However, an increased leakage current density was observed with Ti addition. The data from capacitance-voltage stressing indicate a smaller flatband voltage (V{sub fb}) shift in the HfO{sub 2} films with low Ti content when compared with the HfO{sub 2} films. This indicates less charge trapping with a small amount of Ti addition.

Triyoso, D.H.; Hegde, R.I.; Zollner, S.; Ramon, M.E.; Kalpat, S.; Gregory, R.; Wang, X.-D.; Jiang, J.; Raymond, M.; Rai, R.; Werho, D.; Roan, D.; White, B.E. Jr.; Tobin, P.J. [Freescale Semiconductor, Inc., Advanced Products Research and Development Laboratory, 3501 Ed Bluestein Boulevard, Austin, Texas 78721 (United States)

2005-09-01T23:59:59.000Z

205

Considerations of Alloy N for Fluoride Salt-Cooled High-Temperature Reactor Applications  

SciTech Connect (OSTI)

Fluoride Salt-Cooled High-Temperature Reactors (FHRs) are a promising new class of thermal-spectrum nuclear reactors. The reactor structural materials must possess high-temperature strength and chemical compatibility with the liquid fluoride salt as well as with a power cycle fluid such as supercritical water while remaining resistant to residual air within the containment. Alloy N was developed for use with liquid fluoride salts and it possesses adequate strength and chemical compatibility up to about 700 C. A distinctive property of FHRs is that their maximum allowable coolant temperature is restricted by their structural alloy maximum service temperature. As the reactor thermal efficiency directly increases with the maximum coolant temperature, higher temperature resistant alloys are strongly desired. This paper reviews the current status of Alloy N and its relevance to FHRs including its design principles, development history, high temperature strength, environmental resistance, metallurgical stability, component manufacturability, ASME codification status, and reactor service requirements. The review will identify issues and provide guidance for improving the alloy properties or implementing engineering solutions.

Ren, Weiju [ORNL; Muralidharan, Govindarajan [ORNL; Wilson, Dane F [ORNL; Holcomb, David Eugene [ORNL

2011-01-01T23:59:59.000Z

206

Etching characteristics of high-k dielectric HfO{sub 2} thin films in inductively coupled fluorocarbon plasmas  

SciTech Connect (OSTI)

Inductively coupled fluorocarbon (CF{sub 4}/Ar and C{sub 4}F{sub 8}/Ar) plasmas were used to etch HfO{sub 2}, which is a promising high-dielectric-constant material for the gate of complementary metal-oxide-semiconductor devices. The etch rates of HfO{sub 2} in CF{sub 4}/Ar plasmas exceeded those in C{sub 4}F{sub 8}/Ar plasmas. The tendency for etch rates to become higher in fluorine-rich (high F/C ratio) conditions indicates that HfO{sub 2} can be chemically etched by fluorine-containing species. In C{sub 4}F{sub 8}/Ar plasmas with a high Ar dilution ratio, the etch rate of HfO{sub 2} increased with increasing bias power. The etch rate of Si, however, decreased with bias power, suggesting that the deposition of carbon-containing species increased with increasing the power and inhibited the etching of Si. The HfO{sub 2}/Si selectivity monotonically increased with increasing power, then became more than 5 at the highest tested bias power. The carbon-containing species to inhibit etching of Si play an important role in enhancing the HfO{sub 2}/Si selectivity in C{sub 4}F{sub 8}/Ar plasmas.

Takahashi, Kazuo; Ono, Kouichi; Setsuhara, Yuichi [Department of Aeronautics and Astronautics, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)

2005-11-15T23:59:59.000Z

207

Effects of N{sub 2}, O{sub 2}, and Ar plasma treatments on the removal of crystallized HfO{sub 2} film  

SciTech Connect (OSTI)

The effects of plasma treatment using Ar, N{sub 2}, and O{sub 2} on the removal of crystallized HfO{sub 2} films in a dilute HF solution were studied. The resulting damage in source and drain regions, and recess in isolation regions were also investigated. It was found that plasma nitridation with an ion energy of several hundred electron volts can lower the wet etch resistance of crystallized HfO{sub 2} films up to 70 A thick through the generation of Hf-N bonds. However, thermal nitridation did not introduce sufficient nitrogen into bulk crystallized HfO{sub 2} films to lower wet etch resistance. Plasma nitridation without bias power introduced nitrogen to the crystallized HfO{sub 2} in the region only within 10 A of the surface. The enhancement of the etch rate of crystallized HfO{sub 2} in dilute HF and the amount of recess in the active and isolation regions using N{sub 2}, O{sub 2}, and Ar plasma treatment have been evaluated. Results show that N{sub 2} plasma treatment is the most effective in enhancing the removal rate of crystallized HfO{sub 2} in dilute HF and minimizing recess on substrate among the plasmas studied.

Chen Jinghao; Yoo, Won Jong; Chan, Daniel S.H. [Silicon Nano Device Laboratory, Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore)

2006-01-15T23:59:59.000Z

208

Produce syngas for methanol  

SciTech Connect (OSTI)

Combined reforming, in which an oxygen reforming reactor is added downstream from a conventional tubular reactor to produce syngas for methanol, achieves a substantial reduction in energy consumption with the least impact on the environment. This paper reports that the advantages of this process scheme are as follows: 8% to 10% reduction in the consumption of natural gas per ton of methanol, The size of the primary reformer is reduced, Reduction of syngas compression requirement due to increased syngas pressure, Reduced steam consumption, Production of syngas with the stoichiometric composition required by methanol synthesis. Synthesis gases for the production of methanol and synfuels are basically mixtures of hydrogen and carbon oxides. They have been produced from natural gas by steam reforming, autothermal reforming and noncatalytic partial oxidation.

Farina, G.L. (Foster Wheeler International Corp., Milan (IT))

1992-03-01T23:59:59.000Z

209

Method for producing hydrogen  

SciTech Connect (OSTI)

In a method for producing high quality hydrogen, the carbon monoxide level of a hydrogen stream which also contains hydrogen sulfide is shifted in a bed of iron oxide shift catalyst to a desired low level of carbon monoxide using less catalyst than the minimum amount of catalyst which would otherwise be required if there were no hydrogen sulfide in the gas stream. Under normal operating conditions the presence of even relatively small amounts of hydrogen sulfide can double the activity of the catalyst such that much less catalyst may be used to do the same job.

Preston, J.L.

1980-02-26T23:59:59.000Z

210

Reactions of aluminum with uranium fluorides and oxyfluorides  

SciTech Connect (OSTI)

Every 30 to 40 million operating hours a destructive reaction is observed in one of the {approximately}4000 large compressors that move UF{sub 6} through the gaseous diffusion plants. Despite its infrequency, such a reaction can be costly in terms of equipment and time. Laboratory experiments reveal that the presence of moderate pressures of UF{sub 6} actually cools heated aluminum, although thermodynamic calculations indicate the potential for a 3000-4000{degrees}C temperature rise. Within a narrow and rather low (<100 torr; 1 torr = 133.322 Pa) pressure range, however, the aluminum is seen to react with sufficient heat release to soften an alumina boat. Three things must occur in order for aluminum to react vigorously with either UF{sub 6} or UO{sub 2}F{sub 2}. 1. An initiating source of heat must be provided. In the compressors, this source can be friction, permitted by disruption of the balance of the large rotating part or by creep of the aluminum during a high-temperature treatment. In the absence of this heat source, compressors have operated for 40 years in UF{sub 6} without significant reaction. 2. The film protecting the aluminum must be breached. Melting (of UF{sub 5} at 620 K or aluminum at 930 K) can cause such a breach in laboratory experiments. In contrast, holding Al samples in UF{sub 6} at 870 K for several hours produces only moderate reaction. Rubbing in the cascade can undoubtedly breach the protective film. 3. Reaction products must not build up and smother the reaction. While uranium products tend to dissolve or dissipate in molten aluminum, AIF{sub 3} shows a remarkable tendency to surround and hence protect even molten aluminum. Hence the initial temperature rise must be rapid and sufficient to move reactants into a temperature region in which products are removed from the reaction site.

Leitnaker, J.M.; Nichols, R.W.; Lankford, B.S. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

211

Mechanisms and selectivity for etching of HfO{sub 2} and Si in BCl{sub 3} plasmas  

SciTech Connect (OSTI)

The authors have investigated plasma etching of HfO{sub 2}, a high dielectric constant material, and poly-Si in BCl{sub 3} plasmas. Etching rates were measured as a function of substrate temperature (T{sub s}) at several source powers. Activation energies range from 0.2 to 1.0 kcal/mol for HfO{sub 2} and from 0.8 to 1.8 kcal/mol for Si, with little or no dependence on source power (20-200 W). These low activation energies suggest that product removal is limited by chemical sputtering of the chemisorbed Hf or Si-containing layer, with a higher T{sub s} only modestly increasing the chemical sputtering rate. The slightly lower activation energy for HfO{sub 2} results in a small improvement in selectivity over Si at low temperature. The surface layers formed on HfO{sub 2} and Si after etching in BCl{sub 3} plasmas were also investigated by vacuum-transfer x-ray photoelectron spectroscopy. A thin boron-containing layer was observed on partially etched HfO{sub 2} and on poly-Si after etching through HfO{sub 2} films. For HfO{sub 2}, a single B(1s) feature at 194 eV was ascribed to a heavily oxidized species with bonding similar to B{sub 2}O{sub 3}. B(1s) features were observed for poly-Si surfaces at 187.6 eV (B bound to Si), 189.8 eV, and 193 eV (both ascribed to BO{sub x}Cl{sub y}). In the presence of a deliberately added 0.5% air, the B-containing layer on HfO{sub 2} is largely unaffected, while that on Si converts to a thick layer with a single B(1s) peak at 194 eV and an approximate stoichiometry of B{sub 3}O{sub 4}Cl.

Wang Chunyu; Donnelly, Vincent M. [Department of Chemical and Biomolecular Engineering, University of Houston, 4800 Calhoun Road, Houston, Texas 77204 (United States)

2008-07-15T23:59:59.000Z

212

HF-based etching processes for improving laser damage resistance of fused silica optical surfaces  

SciTech Connect (OSTI)

The effect of various HF-based etching processes on the laser damage resistance of scratched fused silica surfaces has been investigated. Conventionally polished and subsequently scratched fused silica plates were treated by submerging in various HF-based etchants (HF or NH{sub 4}F:HF at various ratios and concentrations) under different process conditions (e.g., agitation frequencies, etch times, rinse conditions, and environmental cleanliness). Subsequently, the laser damage resistance (at 351 or 355 nm) of the treated surface was measured. The laser damage resistance was found to be strongly process dependent and scaled inversely with scratch width. The etching process was optimized to remove or prevent the presence of identified precursors (chemical impurities, fracture surfaces, and silica-based redeposit) known to lead to laser damage initiation. The redeposit precursor was reduced (and hence the damage threshold was increased) by: (1) increasing the SiF{sub 6}{sup 2-} solubility through reduction in the NH4F concentration and impurity cation impurities, and (2) improving the mass transport of reaction product (SiF{sub 6}{sup 2-}) (using high frequency ultrasonic agitation and excessive spray rinsing) away from the etched surface. A 2D finite element crack-etching and rinsing mass transport model (incorporating diffusion and advection) was used to predict reaction product concentration. The predictions are consistent with the experimentally observed process trends. The laser damage thresholds also increased with etched amount (up to {approx}30 {micro}m), which has been attributed to: (1) etching through lateral cracks where there is poor acid penetration, and (2) increasing the crack opening resulting in increased mass transport rates. With the optimized etch process, laser damage resistance increased dramatically; the average threshold fluence for damage initiation for 30 {micro}m wide scratches increased from 7 to 41 J/cm{sup 2}, and the statistical probability of damage initiation at 12 J/cm{sup 2} of an ensemble of scratches decreased from {approx}100 mm{sup -1} of scratch length to {approx}0.001 mm{sup -1}.

Suratwala, T I; Miller, P E; Bude, J D; Steele, R A; Shen, N; Monticelli, M V; Feit, M D; Laurence, T A; Norton, M A; Carr, C W; Wong, L L

2010-02-23T23:59:59.000Z

213

Effect of electron-phonon interaction on resistivity of some heavy fermion (HF) systems  

SciTech Connect (OSTI)

Here, we have analyzed the electron-phonon interaction in the Periodic Anderson Model (PAM) to describe the temperature dependence of resistivity in some heavy fermion (HF) systems for finite wave vector (q) and for finite temperature (T). Since the resistivity is related to the imaginary part of the electron self energy, the expression for the same is evaluated through double time temperature dependant Green function technique of the Zubarev type. The effect of different system parameters namely the position of 4f level, E{sub 0} and the electron - phonon coupling strengths on resistivity have been studied. The results obtained give satisfactory explanations to the experimental observations.

Sahoo, J., E-mail: jitendrasahoo2008@gmail.com [Assistant Director, Regional Office of Vocational Education, Sambalpur, Odisha-768004 (India); Shadangi, N. [Dept. of Physics, Silicon Institute of Technology, Sambalpur, Odisha-768200 (India); Nayak, P. [School of Physics, Sambalpur University, Sambalpur, Odisha-768019 (India)

2014-04-24T23:59:59.000Z

214

A new class of materials with promising thermoelectric properties: MNiSn (M=Ti, Zr, Hf)  

SciTech Connect (OSTI)

TiNiSn, ZrNiSn and HfNiSn are members of a large group of intermetallic compounds which crystallize in the cubic MgAgAs-type structure. Polycrystalline samples of these compounds have been prepared and investigated for their thermoelectric properties. With thermopowers of about {minus}200 {micro}V/K and resistivities of a few m{Omega}cm, power factors S{sup 2}/{rho} as high as 38 {micro}W/K{sup 2}cm were obtained at 700 K. These remarkably high power factors are, however, accompanied by a thermal conductivity, solid solutions Zr{sub 1{minus}x}Hf{sub x}NiSn, Zr{sub 1{minus}x}Ti{sub x}NiSn, and Hf{prime}{sub 1{minus}x}Ti{sub x}NiSn were formed. The figure of merit of Zr{sub 0.5}Hf{sub 0.5}NiSn at 700 K (ZT = 0.41) exceeds the end members ZrNiSn (ZT = 0.26) and HfNiSn (ZT = 0.22).

Hohl, H.; Ramirez, A.P.; Kaefer, W.; Fess, K.; Thurner, Ch.; Kloc, Ch.; Bucher, E.

1997-07-01T23:59:59.000Z

215

Comparison of femtosecond and nanosecond laser-induced damage in HfO{sub 2} single-layer film and HfO{sub 2}-SiO{sub 2} high reflector  

SciTech Connect (OSTI)

HfO{sub 2} single layers, 800 nm high-reflective (HR) coating, and 1064 nm HR coating were prepared by electron-beam evaporation. The laser-induced damage thresholds (LIDTs) and damage morphologies of these samples were investigated with single-pulse femtosecond and nanosecond lasers. It is found that the LIDT of the HfO{sub 2} single layer is higher than the HfO{sub 2}-SiO{sub 2} HR coating in the femtosecond regime, while the situation is opposite in the nanosecond regime. Different damage mechanisms are applied to study this phenomenon. Damage morphologies of all samples due to different laser irradiations are displayed.

Yuan Lei; Zhao Yuanan; Shang Guangqiang; Wang Chengren; He Hongbo; Shao Jianda; Fan Zhengxiu [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China) and Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China) and Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China); Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)

2007-03-15T23:59:59.000Z

216

Suppression of near-edge optical absorption band in sputter deposited HfO{sub 2}-Al{sub 2}O{sub 3} nanolaminates containing nonmonoclinic HfO{sub 2}  

SciTech Connect (OSTI)

Nanolaminates of polycrystalline (tetragonal+orthorhombic) HfO{sub 2} and amorphous Al{sub 2}O{sub 3} are sputter deposited on unheated fused SiO{sub 2}, air annealed at 573-1273 K, and analyzed by x-ray diffraction and spectrophometry. Significant O 2p{yields}Hf 5d interband absorption occurs in all films at energy E{>=}6.2 eV. For E<6.2 eV, films annealed below 1273 K retain a featureless optical absorption edge despite further crystallization. A band with a 5.65 eV onset concurrently develops with m-HfO{sub 2} crystallization after a 1273 K anneal, indicating this phase and not nanocrystallinity per se is responsible for increased absorption.

Hoppe, E. E.; Aita, C. R. [Advanced Coatings Experimental Laboratory, University of Wisconsin-Milwaukee, P.O. Box 784, Milwaukee, Wisconsin 53201 (United States)

2008-04-07T23:59:59.000Z

217

Process for producing ethanol  

SciTech Connect (OSTI)

A process is described for producing ethanol from raw materials containing a high dry solid mash level having fermentable sugars or constituents which can be converted into sugars, comprising the steps of: (a) liquefaction of the raw materials in the presence of an alpha amylase to obtain liquefied mash; (b) saccharification of the liquefied mash in the presence of a glucoamylase to obtain hydrolysed starch and sugars; (c) fermentation of the hydrolysed starch and sugars by yeast to obtain ethanol; and (d) recovering the obtained ethanol, wherein an acid fungal protease is introduced to the liquefied mash during the saccharification and/or to the hydrolysed starch and sugars during the fermentation, thereby increasing the rate of production of ethanol as compared to a substantially similar process conducted without the introduction of the protease.

Lantero, O.J.; Fish, J.J.

1993-07-27T23:59:59.000Z

218

Fluoride removal in the presence of organophosphates: application to chemical warfare agent destruction  

E-Print Network [OSTI]

generated. Of the many commercially available anion exchange resins, two were identified by their manufacturer as possible fluoride exchangers. Rohm & Haas' Amberlite IRA- 400(OH/Gl) and Dow Corporation's Dowex MWA-1 were examined for their ability... crystal 105-107 extremel soluble Table 63: Physical Properties of MPA, GAS? 993-13-5. *As determined by titration, appendix F. APPENDIX C REVIEW OF ION EXCHANGE Ion exchange is based on the principle of a fixed ionic group bound to a resin which...

Wenaas, Christopher Eric

1996-01-01T23:59:59.000Z

219

Methods of using ionic liquids having a fluoride anion as solvents  

DOE Patents [OSTI]

A method in one embodiment includes contacting a strongly hydrogen bonded organic material with an ionic liquid having a fluoride anion for solubilizing the strongly hydrogen bonded organic material; and maintaining the ionic liquid at a temperature of about 90.degree. C. or less during the contacting. A method in another embodiment includes contacting a strongly hydrogen bonded organic material with an ionic liquid having an acetate or formate anion for solubilizing the strongly hydrogen bonded organic material; and maintaining the ionic liquid at a temperature of less than about 90.degree. C. during the contacting.

Pagoria, Philip (Livermore, CA); Maiti, Amitesh (San Ramon, CA); Gash, Alexander (Brentwood, CA); Han, Thomas Yong (Pleasanton, CA); Orme, Christine (Oakland, CA); Fried, Laurence (Livermore, CA)

2011-12-06T23:59:59.000Z

220

[sup 27]Al NMR, GT-IR and ethanol-[sup 18]O TPD characterization of fluorided alumina  

SciTech Connect (OSTI)

New environmental legislation in the United States requiring reformulation of gasoline and diesel fuels is making its necessary to develop better, alternative acid catalysts for alkylation and isomerization reactions, and for hydrotreating catalysts for sulfur and nitrogen removal from refinery streams. A series of F/Al[sub 2]O[sub 3] samples (wt % F = 0 to 20) has been studied using a combination of solid-state [sup 27]Al NMR, FT-IR, and ethanol-[sup 18]O TPD techniques. Solid-state [sup 27]Al NMR is particularly sensitive to amorphous phases or small crystallites present on the catalyst surface, many of which cannot be detected by XRD. [sup 27]Al NMR shows the presence of three types of AlF[sub 3](H[sub 2]O)[sub n] species (with n varying between 0 and 3) on fluorided alumina. FT-IR studies of ethanol adsorption show that fluoride blocks the sites required for dissociative chemisorption of ethanol. A similar analysis of adsorbed pyridine shows an increase in the number of Broensted acid sites with the addition of up to 10 wt % fluoride. However, increasing the fluoride loading to 20 wt % decreases the number of Broensted acid sites. The TPD of ethanol-[sup 18]O from F/Al[sub 2]O[sub 3] samples shows that at low levels fluoride serves to block Lewis acid sites, but at higher levels its predominant role is to increase the Broensted acidity of the alumina surface. The pyridine adsorption and TPD experiments show that fluoride strengthens the remaining Lewis acid sites. 14 figs., 3 tabs.

DeCanio, E.C. (Texaco R D Dept., Beacon, NY (United States) Wesleyan Univ., Middletown, CT (United States)); Bruno, J.W. (Wesleyan Univ., Middletown, CT (United States)); Nero, V.P.; Edwards, J.C. (Texaco R D Dept., Beacon, NY (United States))

1993-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Surface acidity and cumene conversion. II. A study of. gamma. -alumina containing fluoride, cobalt, and molybdenum additives: the effect of reduction  

SciTech Connect (OSTI)

The effect of reduction of the cumene conversion activity of a series of fluoride-impregnated, alumina-supported cobalt-molybdenum catalysts has been investigated. Such catalysts exhibit two different types of Broensted acid sites, one associated with the molybdenum and the other with the fluorided alumina surface. Reduction with H/sub 2/ eliminates the former type of site, but does not affect the latter. Reduction does not affect the activity of the alumina catalyst which is impregnated only with fluoride, but conversions for the other catalysts are reduced by 2-10%. In hydrocracking experiments, the dramatic influence of fluoride impregnation on cumene conversion and the synergistic nature of the fluoride and cobalt/molybdenum are demonstrated.

Boorman, P.M.; Kydd, R.A.; Sarbak, Z.; Somogyvari, A.

1986-08-01T23:59:59.000Z

222

Effective work function of Pt, Pd, and Re on atomic layer deposited HfO{sub 2}  

SciTech Connect (OSTI)

Platinum and Pd show a significant difference in work function on SiO{sub 2} and high-K materials (HfO{sub 2}). The effective metal work functions for Pd, Pt, and Re on atomic layer deposited HfO{sub 2}, which are different from the vacuum work function and important for device threshold voltage control, are measured by the C-V method. The difference is attributed to the dipoles at the metal/HfO{sub 2} interface, which is a result of charge transfer across the interface. Moreover, the extracted charge neutrality level and screening parameter are correlated with the phase development, film stoichiometry, and density of interface states at the metal/high-K interface.

Gu Diefeng; Dey, Sandwip K.; Majhi, Prashant [Department of Chemical and Materials Engineering, Arizona State University, Tempe, Arizona 85287-6006 (United States) and Department of Electrical Engineering, Arizona State University, Tempe, Arizona 85287-5706 (United States); Planar CMOS Scaling, SEMATECH, Austin, Texas 78741 (United States)

2006-08-21T23:59:59.000Z

223

Plasma and vacuum ultraviolet induced charging of SiO{sub 2} and HfO{sub 2} patterned structures  

SciTech Connect (OSTI)

The authors compare the effects of plasma charging and vacuum ultraviolet (VUV) irradiation on oxidized patterned Si structures with and without atomic-layer-deposited HfO{sub 2}. It was found that, unlike planar oxidized Si wafers, oxidized patterned Si wafers charge up significantly after exposure in an electron-cyclotron resonance plasma. The charging is dependent on the aspect ratio of the patterned structures. This is attributed to electron and/or ion shading during plasma exposure. The addition of a 10 nm thick HfO{sub 2} layer deposited on top of the oxidized silicon structures increases the photoemission yield during VUV irradiation, resulting in more trapped positive charge compared to patterns without the HfO{sub 2} dielectric.

Lauer, J. L.; Upadhyaya, G. S.; Sinha, H.; Kruger, J. B.; Nishi, Y.; Shohet, J. L. [Plasma Processing and Technology Laboratory and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Stanford Nanofabrication Facility, Stanford University, Stanford, California 94303 (United States); Stanford University, Stanford, California 94305 (United States); Plasma Processing and Technology Laboratory and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2012-01-15T23:59:59.000Z

224

Local elastic modulus of RF sputtered HfO{sub 2} thin film by atomic force acoustic microscopy  

SciTech Connect (OSTI)

Atomic force acoustic microscopy (AFAM) is a useful nondestructive technique for measurement of local elastic modulus of materials at nano-scale spatial resolution by measuring the contact resonance spectra for higher order modes of the AFM cantilever. The elastic modulus of RF sputtered HfO{sub 2} thin film has been measured quantitatively, using reference approach in which measurements are performed on the test and reference samples. Using AFAM, the measured elastic modulus of the HfO{sub 2} thin film is 223±27 GPa, which is in agreement with the literature value of 220±40 GPa for atomic layer deposited HfO{sub 2} thin film using nanoindentation technique.

Jena, S., E-mail: shuvendujena9@gmail.com; Tokas, R. B., E-mail: shuvendujena9@gmail.com; Sarkar, P., E-mail: shuvendujena9@gmail.com; Thakur, S.; Sahoo, N. K. [Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085 (India); Misal, J. S.; Rao, K. D. [Optics and Thin Film Laboratory, Autonagar, BARC-Vizag, Visakhapatnam-530 012 (India)

2014-04-24T23:59:59.000Z

225

Effects of shock waves on the performance of a cw supersonic HF chemical laser  

SciTech Connect (OSTI)

The effects of oblique shock waves on the gain and the output power of a cw supersonic HF chemical laser are theoretically investigated. A one-dimensional model is used to solve the flow of a premixed H/sub 2/--SF/sub 6/--H/sub e/ or H/sub 2/--F/sub 2/--H/sub e/ mixture through the resonator, allowing the presence of oblique shock waves in the flow. It is shown that a shock wave significantly affects the laser performance due to the gas compression at the shock front and due to acceleration of the chemical and energy transfer processes. It was found that immediately behind the shock front the gain coefficients and the photon energy sharply increase and further downstream they fall off rapidly, thus the profiles of the gain and radiation flux become narrower along the flow direction. Integration of the radiation flux along the cavity coordinate reveals that in some cases the total available power is significantly higher than the available power obtained in the undisturbed flow. For HF lasers pumped by the chain reactions it was found that choking occurs over a wide range of flow parameters including very weak shock waves. This is due to the large amount of heat released by the exothermic reactions.

Stricker, J.; Waichman, K.

1984-09-01T23:59:59.000Z

226

Measurements of spatial and frequency coherence of an equatorial hf path during spread-F  

SciTech Connect (OSTI)

In August 1990, the authors set up an hf path on the equatorial path between Maloelap Atoll and Bikini Atoll. This path, which had a range of 702 km, reflected in the ionosphere approximately 100 km north of the Altair radar location on Kwajalein. Transmitters at Maloelap broadcasted four cw tones within bandwidth of either 4 kHz, 9 kHz, or 70 kHz to be used to determine frequency coherence and also a phase-coded pseudo random sequence with a bandwidth of 60 kHz (channel probe) to be used to determine time delay spread. A spatial array of antennas was deployed at Bikini to measure spatial and frequency coherence using the cw broadcasts. The system was run in the post-sunset time period over two weeks during which almost every night showed significant degradation due to spread F resulting in rapid fading, decreased spatial and frequency coherence, and increased time delay spread. Doppler spreads of greater than 20 Hz were not uncommon, and the spatial correlation distances and frequency coherence bandwidths became so small (50 meters and 1 kHz respectively) that the experiment had to be readjusted. Measurements taken by the Altair incoherent scatter radar and the CUPRI 50 MHz coherent scatter radar indicate that although the bistatic hf channel is affected by the large scale plume structures, most of the [open quotes]damage[close quotes] is done by the bottomside spread F.

Fitzgerald, T.J.; Argo, P.E.; Carlos, R.C.

1993-01-01T23:59:59.000Z

227

Measurements of spatial and frequency coherence of an equatorial hf path during spread-F  

SciTech Connect (OSTI)

In August 1990, the authors set up an hf path on the equatorial path between Maloelap Atoll and Bikini Atoll. This path, which had a range of 702 km, reflected in the ionosphere approximately 100 km north of the Altair radar location on Kwajalein. Transmitters at Maloelap broadcasted four cw tones within bandwidth of either 4 kHz, 9 kHz, or 70 kHz to be used to determine frequency coherence and also a phase-coded pseudo random sequence with a bandwidth of 60 kHz (channel probe) to be used to determine time delay spread. A spatial array of antennas was deployed at Bikini to measure spatial and frequency coherence using the cw broadcasts. The system was run in the post-sunset time period over two weeks during which almost every night showed significant degradation due to spread F resulting in rapid fading, decreased spatial and frequency coherence, and increased time delay spread. Doppler spreads of greater than 20 Hz were not uncommon, and the spatial correlation distances and frequency coherence bandwidths became so small (50 meters and 1 kHz respectively) that the experiment had to be readjusted. Measurements taken by the Altair incoherent scatter radar and the CUPRI 50 MHz coherent scatter radar indicate that although the bistatic hf channel is affected by the large scale plume structures, most of the {open_quotes}damage{close_quotes} is done by the bottomside spread F.

Fitzgerald, T.J.; Argo, P.E.; Carlos, R.C.

1993-07-01T23:59:59.000Z

228

E-Print Network 3.0 - alkali metal thermal Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: , calcium hypochlorite, hydrogen fluoride (HF) Ammonium Nitrate acids, metal powders, flammable liquids... , sodium carbide, turpentine, finely divided metals...

229

E-Print Network 3.0 - alkali metals phase Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: , calcium hypochlorite, hydrogen fluoride (HF) Ammonium Nitrate acids, metal powders, flammable liquids... , sodium carbide, turpentine, finely divided metals...

230

E-Print Network 3.0 - alkali metal dimers Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: , calcium hypochlorite, hydrogen fluoride (HF) Ammonium Nitrate acids, metal powders, flammable liquids... , sodium carbide, turpentine, finely divided metals...

231

E-Print Network 3.0 - alkali metals final Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: , calcium hypochlorite, hydrogen fluoride (HF) Ammonium Nitrate acids, metal powders, flammable liquids... , sodium carbide, turpentine, finely divided metals...

232

E-Print Network 3.0 - alkali metal complexes Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: , calcium hypochlorite, hydrogen fluoride (HF) Ammonium Nitrate acids, metal powders, flammable liquids... , sodium carbide, turpentine, finely divided metals...

233

E-Print Network 3.0 - alkali metal extraction Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: , calcium hypochlorite, hydrogen fluoride (HF) Ammonium Nitrate acids, metal powders, flammable liquids... , sodium carbide, turpentine, finely divided metals...

234

Aluminum hydroxide solubility in aqueous solutions containing fluoride ions at 50/sup 0/Cype  

SciTech Connect (OSTI)

Aluminum hydroxide solubility experiments were performed at 50/sup 0/C using the method of May et al. (1979b). The shift observed by May at 25/sup 0/C between acidic and alkaline solution was also observed in these experiments. Infrared spectra of solids separated from solutions show that the low solubility values observed in alkaline medium can be related to the formation of a new solid phase: bayerite (or nordstrandite) (pK*/sub S/sub 4// = 13.4 at 50/sup 0/C) in the presence of initial gibbsite. A second set of experiments was performed in solutions containing fluoride ions in the 10/sup -4/-10/sup -3/ M concentration range. Fluorocomplexes are important in acidic solution; Al(OH)/sub m/F/sub p/ mixed complexes can be important in the minimum of Al solubility when total fluoride exceeds 10/sup -3/ M. The authors propose values of thermodynamic data for Al(OH)/sub 2/F/sub 2//sup -/, Al(OH)F/sub 3//sup -/, Al(OH)/sub 2/F/sup 0/ and for aluminum trifluoride solid. The difference of aluminum hydroxide solubility between acidic and alkaline medium is still observed.

Sanjuan, B.; Michard, G.

1987-07-01T23:59:59.000Z

235

Measurement of the Melting Point Temperature of Several Lithium-Sodium-Beryllium Fluoride Salt (Flinabe) Mixtures  

SciTech Connect (OSTI)

The molten salt Flibe, a combination of lithium and beryllium fluorides studied for molten salt fission reactors, has been proposed as a breeder and coolant for fusion applications. The melting points of 2LiF-BeF{sub 2} and LiF-BeF{sub 2} are 460 deg. C and 363 deg. C, but LiF-BeF{sub 2} is rather viscous and has less lithium for breeding. In the Advanced Power Extraction (APEX) Program, concepts with a free flowing liquid for the first wall and blanket were investigated. Flinabe (a mixture of LiF, BeF{sub 2} and NaF) was selected for a molten salt design because a melting temperature below 350 deg. C appeared possible and this provided an attractive operating temperature window for a reactor. To confirm that a ternary salt with a low melting temperature existed, several combinations of the fluoride salts, LiF, NaF and BeF{sub 2}, were melted in a stainless steel crucible under vacuum. One had an apparent melting temperature of 305 deg. C. The test system, preparation of the mixtures, melting procedures and temperature curves for the melting and cooling are presented along with the apparent melting points. Thermal modeling of the salt pool and crucible is reported in an accompanying paper.

McDonald, J.M; Nygren, R.E.; Lutz, T.J.; Tanaka, T.J; Ulrickson, M.A.; Boyle, T.J.; Troncosa, K.P. [Sandia National Laboratories (United States)

2005-04-15T23:59:59.000Z

236

Effect of Phosphate, Fluoride, and Nitrate on Gibbsite Dissolution Rate and Solubility  

SciTech Connect (OSTI)

Laboratory tests have been completed with simulated tank waste samples to investigate the effects of phosphate, fluoride, and nitrate on the dissolution rate and equilibrium solubility of gibbsite in sodium hydroxide solution at 22 and 40{degrees}C. Results are compared to relevant literature data and to computer model predictions. The presence of sodium nitrate (3 M) caused a reduction in the rate of gibbsite dissolution in NaOH, but a modest increase in the equilibrium solubility of aluminum. The increase in solubility was not as large, though, as the increase predicted by the computer model. The presence of phosphate, either as sodium phosphate or sodium fluoride phosphate, had a negligible effect on the rate of gibbsite dissolution, but caused a slight increase in aluminum solubility. The magnitude of the increased solubility, relative to the increase caused by sodium nitrate, suggests that the increase is due to ionic strength (or water activity) effects, rather than being associated with the specific ion involved. The computer model predicted that phosphate would cause a slight decrease in aluminum solubility, suggesting some Al-PO4 interaction. No evidence was found of such an interaction.

Herting, Daniel L. [Washington River Protection Solutions LLC (United States)

2014-01-29T23:59:59.000Z

237

Interplay between gadolinium dopants and oxygen vacancies in HfO{sub 2}: A density functional theory plus Hubbard U investigation  

SciTech Connect (OSTI)

The influence of gadolinium (Gd) doping on the oxygen vacancy (V{sub O}) in monoclinic HfO{sub 2} have been studied by the first-principles calculations within the spin-polarized generalized gradient approximation plus Hubbard U approach. It is found that the Gd dopant and V{sub O} show strong attractive interaction, resulting in a cooperative effect that the substitution of Gd for Hf (Gd{sub Hf}) would increase the probability of oxygen vacancies generation and vice versa. The Gd{sub Hf} is more energetically favorable to be next to the vacancy site of a three-coordinated oxygen (O3), forming a complex defect Gd{sub Hf} + V{sub O}. A single Gd{sub Hf} acts a hole donor and passivates the defect states of V{sub O}. Our results suggest that the decrease of the V{sub O}-related defect states observed in the photoluminescence spectra of Gd-HfO{sub 2} is because Gd doping passivates the defect states of V{sub O}, rather than caused by decrease of V{sub O} concentration. Our findings would clarify the debate about the influence of Gd doping on the oxygen vacancies in HfO{sub 2}.

Zhang, Wei [Department of Criminal Science and Technology, Nanjing Forest Police College, Nanjing 210023 (China); Hou, Z. F., E-mail: zhufeng.hou@gmail.com [Department of Electronic Science, Xiamen University, Xiamen 361005 (China)

2014-03-28T23:59:59.000Z

238

13.21 Geochemistry of the Rare-Earth Element, Nb, Ta, Hf, and Zr Deposits RL Linnen, University of Western Ontario, London, ON, Canada  

E-Print Network [OSTI]

13.21 Geochemistry of the Rare-Earth Element, Nb, Ta, Hf, and Zr Deposits RL Linnen, University to Y, the rare- earth elements (REE, La to Lu), Zr, Hf, Nb, and Ta. The rare elements, Canada ã 2014 Elsevier Ltd. All rights reserved. 13.21.1 Introduction 543 13.21.1.1 Uses of Rare Elements

Chakhmouradian, Anton

239

A comparison of EISCAT and HF Doppler observations of a ULF wave D. M. Wright, T. K. Yeoman, J. A. Davies  

E-Print Network [OSTI]

A comparison of EISCAT and HF Doppler observations of a ULF wave D. M. Wright, T. K. Yeoman, J. A, Wright et al. (1997) presented a detailed study of ULF wave signatures observed by a new sounder at high observed by HF Doppler Correspondence to: D. M. Wright Presented at the Eighth International EISCAT

Paris-Sud XI, Université de

240

A Minimum Free Energy Reaction Path for the E2 Reaction between Fluoro Ethane and a Fluoride Ion  

E-Print Network [OSTI]

A Minimum Free Energy Reaction Path for the E2 Reaction between Fluoro Ethane and a Fluoride Ion, such as the mechanism and the free-energy profile, remains an important challenge not only for enzyme catalysis1 of the reaction free-energy profile is very cumbersome with constrained molecular dynamics (MD) and umbrella

Nielsen, Steven O.

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Luminescence and electrical properties of solution-processed ZnO thin films by adding fluorides and annealing atmosphere  

SciTech Connect (OSTI)

Highlights: {yields} Systematic study of the fluorides doped solution-processed ZnO thin films via the luminescence and electrical behaviors. {yields} Defect-related visible emission bands are affected by annealing ambient and fluoride addition. {yields} Adding lithium fluoride followed by annealing in oxygen ambient leads to a controlled defect density with proper TFT performance. -- Abstract: To develop an efficient channel layer for thin film transistors (TFTs), understanding the defect-related luminescence and electrical property is crucial for solution-processed ZnO thin films. Film growth with the fluorides addition, especially using LiF, followed by the oxygen ambient post-annealing leads to decreased defect-related emission as well as enhanced switching property. The saturation mobility and current on/off ratio are 0.31 cm{sup 2} V{sup -1} s{sup -1} and 1.04 x 10{sup 3}. Consequently, we can visualize an optimized process condition and characterization method for solution-processed TFT based on the fluorine-doped ZnO film channel layer by considering the overall emission behavior.

Choi, Sungho, E-mail: shochoi@krict.re.kr [Advanced Materials Division, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 305-600 (Korea, Republic of)] [Advanced Materials Division, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 305-600 (Korea, Republic of); Park, Byung-Yoon [Chemical and Electronic Materials Division, LG Electronics, Hyangjeong-dong, Heungdeok-gu, Cheongju (Korea, Republic of)] [Chemical and Electronic Materials Division, LG Electronics, Hyangjeong-dong, Heungdeok-gu, Cheongju (Korea, Republic of); Jung, Ha-Kyun [Advanced Materials Division, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 305-600 (Korea, Republic of)] [Advanced Materials Division, Korea Research Institute of Chemical Technology, Yuseong, Daejeon 305-600 (Korea, Republic of)

2011-06-15T23:59:59.000Z

242

An experimental study of the aqueous solubility and speciation of Y(III) fluoride at temperatures up to 250 C  

E-Print Network [OSTI]

are known to be of hydrothermal origin or modified by hydrothermal processes (e.g., Oreskes and Einaudi information on the behavior of the REE in hydrothermal processes is essential for a better understanding fluoride-rich hydrothermal systems. Our results emphasize the usefulness of the Y/Ho ratio as a geochemical

Devernal, Anne

243

Energy transfer kinetics in oxy-fluoride glass and glass-ceramics doped with rare-earth ions  

SciTech Connect (OSTI)

An investigation of donor-acceptor energy transfer kinetics in dual rare earths doped precursor oxy-fluoride glass and its glass-ceramics containing NaYF{sub 4} nano-crystals is reported here, using three different donor-acceptor ion combinations such as Nd-Yb, Yb-Dy, and Nd-Dy. The precipitation of NaYF{sub 4} nano-crystals in host glass matrix under controlled post heat treatment of precursor oxy-fluoride glasses has been confirmed from XRD, FESEM, and transmission electron microscope (TEM) analysis. Further, the incorporation of dopant ions inside fluoride nano-crystals has been established through optical absorption and TEM-EDX analysis. The noticed decreasing trend in donor to acceptor energy transfer efficiency from precursor glass to glass-ceramics in all three combinations have been explained based on the structural rearrangements that occurred during the heat treatment process. The reduced coupling phonon energy for the dopant ions due to fluoride environment and its influence on the overall phonon assisted contribution in energy transfer process has been illustrated. Additionally, realization of a correlated distribution of dopant ions causing clustering inside nano-crystals has also been reported.

Sontakke, Atul D.; Annapurna, K. [Glass Science and Technology Section, CSIR-Central Glass and Ceramic Research Institute, 196, Raja S. C. Mullick Road, Kolkata - 700 032 (India)

2012-07-01T23:59:59.000Z

244

Computational investigation of the phase stability and the electronic properties for Gd-doped HfO{sub 2}  

SciTech Connect (OSTI)

Rare earth doping is an important approach to improve the desired properties of high-k gate dielectric oxides. We have carried out a comprehensive theoretical investigation on the phase stability, band gap, formation of oxygen vacancies, and dielectric properties for the Gd-doped HfO{sub 2}. Our calculated results indicate that the tetragonal phase is more stable than the monoclinic phase when the Gd doping concentration is greater than 15.5%, which is in a good agreement with the experimental observations. The dopant's geometric effect is mainly responsible for the phase stability. The Gd doping enlarges the band gap of the material. The dielectric constant for the Gd-doped HfO{sub 2} is in the range of 20–30 that is suitable for high-k dielectric applications. The neutral oxygen vacancy formation energy is 3.2?eV lower in the doped material than in pure HfO{sub 2}. We explain the experimental observation on the decrease of photoluminescence intensities in the Gd-doped HfO{sub 2} according to forming the dopant-oxygen vacancy complexes.

Wang, L. G. [General Research Institute for Nonferrous Metals, Beijing 100088 (China); California Institute of Technology, Pasadena, California 91125 (United States); Xiong, Y.; Xiao, W.; Cheng, L.; Du, J.; Tu, H. [General Research Institute for Nonferrous Metals, Beijing 100088 (China); Walle, A. van de [Brown University, Providence, Rhode Island 02912 (United States); California Institute of Technology, Pasadena, California 91125 (United States)

2014-05-19T23:59:59.000Z

245

Analytical Potential Energy Surface for the Na + HF NaF + H reaction: Application of Conventional Transition-State Theory  

E-Print Network [OSTI]

Analytical Potential Energy Surface for the Na + HF NaF + H reaction: Application of Conventional Transition-State Theory Alessandra F. A. Vilela, Ricardo Gargano a Patr´icia R.P. Barreto b a Instituto de from calculation of the rate constant using con- ventional Transition State Theory (TST

246

NEW ACTIVE LOAD VOLTAGE CLAMP FOR HF-LINK CONVERTERS Petar Ljusev and Michael A.E. Andersen  

E-Print Network [OSTI]

that incorporates both the main power and auxiliary transformer on the same magnetic core. Keywords: HF not need additional power components, but do have increased control complexity and safety problems. The latter solutions satisfy both the commutation and safety issues, but ask for additional power components

247

Computer simulations for direct conversion of the HF electromagnetic wave into the upper hybrid wave in ionospheric heating experiments  

E-Print Network [OSTI]

Computer simulations for direct conversion of the HF electromagnetic wave into the upper hybrid emissions (SEE). A direct conversion process is proposed as an excitation mech- anism of the upper hybrid, 1996) The electrostatic waves at the UH resonance were assumed to be excited via ``direct conversion

Paris-Sud XI, Université de

248

The Long Wavelength Array (LWA): A Large HF/VHF Array for Solar Physics, Ionospheric Science, and Solar Radar  

E-Print Network [OSTI]

The Long Wavelength Array (LWA): A Large HF/VHF Array for Solar Physics, Ionospheric Science, and Solar Radar Namir E. Kassim Naval Research Laboratory, Washington, DC 20375 Stephen M. White AFRL will be a powerful tool for solar physics and space weather investigations, through its ability to characterize

Ellingson, Steven W.

249

Role of hydrogen in Ge/HfO2/Al gate stacks subjected to negative bias temperature instability  

E-Print Network [OSTI]

Role of hydrogen in Ge/HfO2/Al gate stacks subjected to negative bias temperature instability N 2007; published online 17 January 2008 This work investigates the role of hydrogen and nitrogen in a Ge. Virtually unchanged interface state density as a function of NBTI indicates no atomic hydrogen release from

Misra, Durgamadhab "Durga"

250

Gas-phase hydrogen isotope exchange in HF + D2O  

SciTech Connect (OSTI)

The gas-phase isotope exchange reaction of HF and D2O has been studied by flow tube and matrix isolation techniques over a range of concentrations and reaction times. The matrix isolation/FTIR gas sampling and analysis technique proved capable of detecting reactants and products even at low concentrations (0.02% and less) and for reaction times down to 10 msec. The reaction under study, however, is sufficiently rapid that it appeared complete at 10 msec even at the lowest reactant concentrations used. From these results, it is therefore possible only to place a lower bound on the reaction rate. This lower bound, arrived at by computer modeling an assumed second order reaction in the flow tube, represents a refinement in the previously established limit by about a factor of 10U and may thus be of utility in UF6 atmospheric release models. 4 refs., 13 figs., 2 tabs.

Trowbridge, L.D.

1982-12-31T23:59:59.000Z

251

Electric transport properties of the pentatelluride materials HfTe{sub 5} and ZrTe{sub 5}  

SciTech Connect (OSTI)

The authors have measured the resistivity and thermopower of single crystals as well as polycrystalline pressed powders of the low-dimensional pentatelluride materials: HfTe{sub 5} and ZrTe{sub 5}. They have performed these measurements as a function of temperature between 5K and 320K. In the single crystals there is a peak in the resistivity for both materials at a peak temperature, T{sub p} where T{sub p} {approx} 80K for HfTe{sub 5} and T{sub p} {approx} 145K for ZrTe{sub 5}. Both materials exhibit a large p-type thermopower around room temperature which undergoes a change to n-type below the peak. These data are similar to behavior observed previously in these materials. They have also synthesized pressed powders of polycrystalline pentatelluride materials, HfTe{sub 5} and ZrTe{sub 5}. They have measured the resistivity and thermopower of these polycrystalline materials as a function of temperature between 5K and 320K. For the polycrystalline material, the room temperature thermopower for each of these materials is relatively high, +95 {micro}V/K and +65 {micro}V/K for HfTe{sub 5} and ZrTe{sub 5}, respectively. These values compare closely to thermopower values for single crystals of these materials. At 77 K, the thermopower is +55 {micro}V/K for HfTe{sub 5} and +35 {micro}V/K for ZrTe{sub 5}. In fact, the thermopower for the polycrystals decreases monotonically with temperature to T {approx} 5K, thus exhibiting p-type behavior over the entire range of temperature. As expected, the resistivity for the polycrystals is higher than the single crystal material, with values of 430 m{Omega}-cm and 24 m{Omega}-cm for HfTe{sub 5} and ZrTe{sub 5} respectively, compared to single crystal values of 0.35 m{Omega}-cm (HfTe{sub 5}) and 1.0 m{Omega}-cm (ZrTe{sub 5}). The authors have found that the peak in the resistivity evident in both single crystal materials is absent in these polycrystalline materials. They will discuss these materials in relation to their potential as candidates for thermoelectric applications.

Tritt, T.M.; Wilson, M.L.; Littleton, R.L. [and others

1997-07-01T23:59:59.000Z

252

Solid Solubilities of Pu, U, Gd and Hf in Candidate Ceramic Nuclear Wasteforms  

SciTech Connect (OSTI)

This goal of this research project was to determine the solid solubility of Pu, U, Gd, and Hf in candidate ceramics for immobilization of high-level nuclear waste. The experimental approach was to saturate each phase by adding more than the solid solubility limit of the given cation, using a nominated substitution scheme, and then analyzing the candidate phase that formed to evaluate the solid solubility limit under firing conditions. Confirmation that the solid solution limit had been reached insofar as other phases rich in the cation of interest was also required. The candidate phases were monazite, titanite, zirconolite, perovskite, apatite, pyrochlore, and brannerite. The valences of Pu and U were typically deduced from the firing atmosphere, and charge balancing in the candidate phase composition as evaluated from electron microscopy, although in some cases it was measured directly by x-ray absorption and diffuse reflectance spectroscopies (for U). Tetravalent Pu and U have restricted (< 0.1 formula units) solid solubility in apatite, titanite, and perovskite. Trivalent Pu has a larger solubility in apatite and perovskite than Pu4+. U3+ appears to be a credible species in reduced perovskite with a solubility of {approximately} 0.25 f.u. as opposed to {approximately} 0.05 f.u. for U4+. Pu4+ is a viable species in monazite and is promoted at lower firing temperatures ({approximately} 800 C) in an air atmosphere. Hf solubility is restricted in apatite, monazite (< 0.1 f.u.), but is {approximately} 0.2 and 0.5 f.u. in brannerite and titanite, respectively. Gd solubility is extended in all phases except for titanite ({approximately} 0.3 f.u.). U5+ was identified by DRS observations of absorption bands in the visible/near infrared photon energy ranges in brannerite and zirconolite, and U4+ in zirconolite was similarly identified.

Vance, Eric R.; Carter, M. L.; Lumpkin, G. R.; Day, R. A.; Begg, B. D.

2001-04-02T23:59:59.000Z

253

Mechanisms for plasma etching of HfO{sub 2} gate stacks with Si selectivity and photoresist trimming  

SciTech Connect (OSTI)

To minimize leakage currents resulting from the thinning of the insulator in the gate stack of field effect transistors, high-dielectric constant (high-k) metal oxides, and HfO{sub 2} in particular, are being implemented as a replacement for SiO{sub 2}. To speed the rate of processing, it is desirable to etch the gate stack (e.g., metal gate, antireflection layers, and dielectric) in a single process while having selectivity to the underlying Si. Plasma etching using Ar/BCl{sub 3}/Cl{sub 2} mixtures effectively etches HfO{sub 2} while having good selectivity to Si. In this article, results from integrated reactor and feature scale modeling of gate-stack etching in Ar/BCl{sub 3}/Cl{sub 2} plasmas, preceded by photoresist trimming in Ar/O{sub 2} plasmas, are discussed. It was found that BCl{sub n} species react with HfO{sub 2}, which under ion impact, form volatile etch products such as B{sub m}OCl{sub n} and HfCl{sub n}. Selectivity to Si is achieved by creating Si-B bonding as a precursor to the deposition of a BCl{sub n} polymer which slows the etch rate relative to HfO{sub 2}. The low ion energies required to achieve this selectivity then challenge one to obtain highly anisotropic profiles in the metal gate portion of the stack. Validation was performed with data from literature. The effect of bias voltage and key reactant probabilities on etch rate, selectivity, and profile are discussed.

Shoeb, Juline; Kushner, Mark J. [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109-2122 (United States)

2009-11-15T23:59:59.000Z

254

Controlled crystallization and properties of zirconium fluoride-based glass-ceramics  

SciTech Connect (OSTI)

51ZrF{sub 4}{center_dot}16BaF{sub 2}{center_dot}5LaF{sub 3}{center_dot}20LiF{center_dot}5PbF{sub 2} glasses were prepared with CdF{sub 2} additions of 0, 2, 5, and 7.5 mol%. The glasses with 2 and 5 mol% exhibited controllable nucleation upon heat treatment above the glass transformation temperature. The nucleation and crystallization of glasses with 5 mol% CdF{sub 2} were characterized using bulk heat treatments, differential scanning calorimetry, and scanning electron microscopy. The isothermal crystallization of nucleated glasses resulted in the formation of a glass-ceramic that was transparent in the infrared (>70% transmission) and more resistant to fracture than typical fluoride glasses.

Jewell, J.M.; Friebele, E.J.; Aggarwal, I.D. [Naval Research Lab., Washington, DC (United States). Optical Sciences Div.

1996-09-01T23:59:59.000Z

255

Structural study of VO {sub x} doped aluminium fluoride and aluminium oxide catalysts  

SciTech Connect (OSTI)

The structural properties of vanadium doped aluminium oxyfluorides and aluminium oxides, prepared by a modified sol-gel synthesis route, were thoroughly investigated. The influence of the preparation technique and the calcination temperature on the coordination of vanadium, aluminium and fluorine was analysed by different spectroscopic methods such as Raman, MAS NMR and ESR spectroscopy. In all samples calcined at low temperatures (350 deg. C), vanadium coexists in two oxidation states V{sup IV} and V{sup V}, with V{sup IV} as dominating species in the vanadium doped aluminium oxyfluorides. In the fluoride containing solids aluminium as well as vanadium are coordinated by fluorine and oxygen. Thermal annealing of 800 deg. C leads to an extensive reorganisation of the original matrices and to the oxidation of V{sup IV} to V{sup V} in both systems. - Graphical abstract: Structure model for VO {sub x} doped aluminium oxide.

Scheurell, Kerstin [Institute of Chemistry, Humboldt University of Berlin, Brook-Taylor-Street 2, Berlin D-12489 (Germany); Scholz, Gudrun [Institute of Chemistry, Humboldt University of Berlin, Brook-Taylor-Street 2, Berlin D-12489 (Germany); Kemnitz, Erhard [Institute of Chemistry, Humboldt University of Berlin, Brook-Taylor-Street 2, Berlin D-12489 (Germany)], E-mail: erhard.kemnitz@chemie.hu-berlin.de

2007-02-15T23:59:59.000Z

256

Fluoride Salt-Cooled High-Temperature Reactor Technology Development and Demonstration Roadmap  

SciTech Connect (OSTI)

Fluoride salt-cooled High-temperature Reactors (FHRs) are an emerging reactor class with potentially advantageous performance characteristics, and fully passive safety. This roadmap describes the principal remaining FHR technology challenges and the development path needed to address the challenges. This roadmap also provides an integrated overview of the current status of the broad set of technologies necessary to design, evaluate, license, construct, operate, and maintain FHRs. First-generation FHRs will not require any technology breakthroughs, but do require significant concept development, system integration, and technology maturation. FHRs are currently entering early phase engineering development. As such, this roadmap is not as technically detailed or specific as would be the case for a more mature reactor class. The higher cost of fuel and coolant, the lack of an approved licensing framework, the lack of qualified, salt-compatible structural materials, and the potential for tritium release into the environment are the most obvious issues that remain to be resolved.

Holcomb, David Eugene [ORNL; Flanagan, George F [ORNL; Mays, Gary T [ORNL; Pointer, William David [ORNL; Robb, Kevin R [ORNL; Yoder Jr, Graydon L [ORNL

2013-11-01T23:59:59.000Z

257

Barium fluoride whispering-gallery-mode disk-resonator with one billion quality-factor  

E-Print Network [OSTI]

We demonstrate a monolithic optical whispering gallery mode resonator fabricated with barium fluoride (BaF$_2$) with an ultra-high quality ($Q$) factor above $10^9$ at $1550$ nm, and measured with both the linewidth and cavity-ring-down methods. Vertical scanning optical profilometry shows that the root mean square surface roughness of $2$ nm is achieved for our mm-size disk. To the best of our knowledge, we show for the first time that one billion $Q$-factor is achievable by precision polishing in relatively soft crystals with mohs hardness of ~$3$. We show that complex thermo-optical dynamics can take place in these resonators. Beside usual applications in nonlinear optics and microwave photonics, high energy particle scintillation detection utilizing monolithic BaF$_2$ resonators potentially becomes feasible.

Lin, Guoping; Henriet, Rémi; Jacquot, Maxime; Chembo, Yanne K

2015-01-01T23:59:59.000Z

258

Stabilization of Th{sup 3+} ions into mixed-valence thorium fluoride  

SciTech Connect (OSTI)

The unusual oxidation state +3 of the thorium has been stabilized into a lithium containing non-stoichiometric mixed-valence (III/IV) thorium fluorinated phase with formula Li{sub 2+x}Th{sub 12}F{sub 50} (0fluoride. The electrochemical insertion of Li{sup +} ions into the open channels of the host matrix has been carried out at 60 {sup o}C, using an alkylcarbonate PC-LiClO{sub 4} 1 M electrolyte. The Li{sup +} and Th{sup 3+} contents, both in the starting composition and the Li{sup +} inserted ones, were investigated by high resolution solid state {sup 7}Li NMR and EPR, respectively. -- Graphical abstract: Electrochemical insertion of Li{sup +} ions into mixed-valence III/IV thorium fluoride and EPR spectra for the raw and inserted compounds. Display Omitted

Dubois, Marc, E-mail: marc.dubois@univ-bpclermont.f [Clermont Universite, Universite Blaise Pascal, Laboratoire des Materiaux Inorganiques, BP 10448, F-63000 Clermont-Ferrand (France); CNRS, UMR 6002, LMI, F-63177 Aubiere (France); Dieudonne, Belto; Mesbah, Adel; Bonnet, Pierre; El-Ghozzi, Malika [Clermont Universite, Universite Blaise Pascal, Laboratoire des Materiaux Inorganiques, BP 10448, F-63000 Clermont-Ferrand (France); CNRS, UMR 6002, LMI, F-63177 Aubiere (France); Renaudin, Guillaume [Clermont Universite, ENSCCF, Laboratoire des Materiaux Inorganiques, BP 10448, F-63000 Clermont-Ferrand (France); CNRS, UMR 6002, LMI, F-63177 Aubiere (France); Avignant, Daniel [Clermont Universite, Universite Blaise Pascal, Laboratoire des Materiaux Inorganiques, BP 10448, F-63000 Clermont-Ferrand (France); CNRS, UMR 6002, LMI, F-63177 Aubiere (France)

2011-01-15T23:59:59.000Z

259

Direct observation of bias-dependence potential distribution in metal/HfO{sub 2} gate stack structures by hard x-ray photoelectron spectroscopy under device operation  

SciTech Connect (OSTI)

Although gate stack structures with high-k materials have been extensively investigated, there are some issues to be solved for the formation of high quality gate stack structures. In the present study, we employed hard x-ray photoelectron spectroscopy in operating devices. This method allows us to investigate bias dependent electronic states, while keeping device structures intact. Using this method, we have investigated electronic states and potential distribution in gate metal/HfO{sub 2} gate stack structures under device operation. Analysis of the core levels shifts as a function of the bias voltage indicated that a potential drop occurred at the Pt/HfO{sub 2} interface for a Pt/HfO{sub 2} gate structure, while a potential gradient was not observed at the Ru/HfO{sub 2} interface for a Ru/HfO{sub 2} gate structure. Angle resolved photoelectron spectroscopy revealed that a thicker SiO{sub 2} layer was formed at the Pt/HfO{sub 2} interface, indicating that the origin of potential drop at Pt/HfO{sub 2} interface is formation of the thick SiO{sub 2} layer at the interface. The formation of the thick SiO{sub 2} layer at the metal/high-k interface might concern the Fermi level pinning, which is observed in metal/high-k gate stack structures.

Yamashita, Y. [National Institute for Materials Science, Advanced Electric Materials Center, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); National Institute for Materials Science, NIMS Beamline Station at SPring-8, 1-1-1 Kôto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Yoshikawa, H.; Kobayashi, K. [National Institute for Materials Science, NIMS Beamline Station at SPring-8, 1-1-1 Kôto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Chikyo, T. [National Institute for Materials Science, Advanced Electric Materials Center, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

2014-01-28T23:59:59.000Z

260

Thermodynamic properties and interfacial layer characteristics of HfO{sub 2} thin films deposited by plasma-enhanced atomic layer deposition  

SciTech Connect (OSTI)

The thermodynamic properties and interfacial characteristics of HfO{sub 2} thin films that were deposited by the direct plasma atomic layer deposition (DPALD) method are investigated. The as-deposited HfO{sub 2} films that were deposited by the DPALD method show crystallization of the HfO{sub 2} layers, which initiates at approximately the 35th cycle (about 2.8 nm) of the DPALD process. Medium-energy ion scattering analysis reveals that the direct O{sub 2} plasma causes a compositional change in the interfacial layer as the process progresses. With an increase in the number of process cycles, the Si content decreases and the O content increases at that position, so that the HfO{sub 2}-like Hf-silicate layer is formed on top of the interfacial layer. The enhanced physical reactivity of the oxygen ions in the direct plasma and the Hf-silicate layer may be the driving forces that accelerate the early crystallization of the HfO{sub 2} layer in the DPALD process in the as-deposited state.

Kim, Inhoe; Kuk, Seoungwoo; Kim, Seokhoon; Kim, Jinwoo; Jeon, Hyeongtag; Cho, M.-H.; Chung, K.-B. [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Korea Research Institute of Standard and Science, Daejeon 305-600 (Korea, Republic of)

2007-05-28T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Assessment of the Use of Nitrogen Trifluoride for Purifying Coolant and Heat Transfer Salts in the Fluoride Salt-Cooled High-Temperature Reactor  

SciTech Connect (OSTI)

This report provides an assessment of the use of nitrogen trifluoride for removing oxide and water-caused contaminants in the fluoride salts that will be used as coolants in a molten salt cooled reactor.

Scheele, Randall D.; Casella, Andrew M.

2010-09-28T23:59:59.000Z

262

Liquid-liquid equilibria for hydrogen fluoride + 1,1-dichloro-1-fluoroethane + 1-chloro-1,1-difluoroethane at {minus}20 and 20 C  

SciTech Connect (OSTI)

1,1-Dichloro-1-fluoroethane is presently under consideration as a replacement for trichlorofluoromethane, which is widely used as a foam blowing agent. 1-Chloro-1,1-difluoroethane is the major raw material for the production of poly(vinylidene fluoride). These two materials are normally manufactured by the fluorination of 1,1,1-trichloroethane or vinylidene chloride with hydrogen fluoride. A phase separator is normally used to retrieve hydrogen fluoride from the product stream. To design the phase separator, liquid-liquid equilibrium data are required. Liquid-liquid equilibria for the ternary system (hydrogen fluoride + 1,1-dichloro-1-fluoroethane + 1-chloro-1,1-difluoroethane) have been measured at {minus}20 and 20 C. The results are correlated with the NRTL model, and the relevant parameters are presented.

Kang, Y.W.; Lee, Y.Y. [KIST, Seoul (Korea, Republic of). CFC Alternatives Technology Center

1995-03-01T23:59:59.000Z

263

Beyond Conventional Cathode Materials for Li-ion Batteries and Na-ion Batteries Nickel fluoride conversion materials and P2 type Na-ion intercalation cathodes /  

E-Print Network [OSTI]

active material for Li-ion battery, Fe2OF4. ElectrochemistryIron Fluoride, in a Li Ion Battery: A Solid-State NMR, X-raymaterials for Li-ion battery……………………………133 8.2. P2 type

Lee, Dae Hoe

2013-01-01T23:59:59.000Z

264

Method of producing submicron size particles and product produced thereby  

DOE Patents [OSTI]

Submicron size particles are produced by using a sputtering process to deposit particles into a liquid. The liquid is processed to recover the particles therefrom, and the particles have sizes in the range of twenty to two hundred Angstroms. Either metallic or non-metallic particles can be produced, and the metallic particles can be used in ''metallic inks.'' 4 figs.

Bourne, R.S.; Eichman, C.C.; Welbon, W.W.

1988-05-11T23:59:59.000Z

265

Total ionizing dose effect of ?-ray radiation on the switching characteristics and filament stability of HfOx resistive random access memory  

SciTech Connect (OSTI)

The total ionizing dose (TID) effect of gamma-ray (?-ray) irradiation on HfOx based resistive random access memory was investigated by electrical and material characterizations. The memory states can sustain TID level ?5.2 Mrad (HfO{sub 2}) without significant change in the functionality or the switching characteristics under pulse cycling. However, the stability of the filament is weakened after irradiation as memory states are more vulnerable to flipping under the electrical stress. X-ray photoelectron spectroscopy was performed to ascertain the physical mechanism of the stability degradation, which is attributed to the Hf-O bond breaking by the high-energy ?-ray exposure.

Fang, Runchen; Yu, Shimeng, E-mail: shimengy@asu.edu [School of Computing, Informatics, and Decision Systems Engineering, Arizona State University, Tempe, Arizona 85281 (United States); School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States); Gonzalez Velo, Yago; Chen, Wenhao; Holbert, Keith E.; Kozicki, Michael N.; Barnaby, Hugh [School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States)

2014-05-05T23:59:59.000Z

266

Effects of fluoride emissions from a modern primary aluminum smelter on a local population of white-tailed deer (Odocoileus virginianus)  

SciTech Connect (OSTI)

The influence of fluoride emissions from a modern aluminum smelter on concentrations of skeletal fluoride and dental fluorosis in a resident population of white-tailed deer was studied. The smelter was located on Mount Holly Plantation in South Carolina, and concentrations of skeletal fluoride in the deer collected at Mount Holly increased approximately five-fold 3 yr after the operation began. Increases in skeletal fluoride of less than two-fold were observed in deer obtained from Medway Plantation which has its nearest boundary 1.6 km from the smelter site. No dental fluorosis was observed in deer collected at Medway Plantation, but mild dental fluorosis was observed in a significant number of deer collected at Mount Holly Plantation. The dental fluorosis that was observed was not associated with incisor wear or with fluoride-induced molar wear. Osteofluorosis of mandibles or metacarpals was not observed in any of the deer obtained from either plantation. The data obtained from this study indicated that the presence of a modern aluminum smelter caused a detectable increase in concentration of skeletal fluoride in the resident population of white-tailed deer, but that no adverse health effects were seen.

Suttie, J.S.; Dickie, R.; Clay, A.B.; Nielsen, P.; Mahan, W.E.; Baumann, D.P.; Hamilton, R.J.

1987-01-01T23:59:59.000Z

267

Effect of thermal annealing on charge exchange between oxygen interstitial defects within HfO{sub 2} and oxygen-deficient silicon centers within the SiO{sub 2}/Si interface  

SciTech Connect (OSTI)

We compare the charging response of rapid thermally annealed (800 and 1000 deg. C) 4 nm thick HfO{sub 2} to as-deposited HfO{sub 2} on Si by measuring the surface potential of the HfO{sub 2} layers after vacuum ultraviolet (VUV) irradiation with 11.6 eV photons. From VUV spectroscopy, we determined all HfO{sub 2} layers show the presence of oxygen-interstitial defects (OIDs). The electronic states of OID in HfO{sub 2} line up in energy with oxygen-deficient Si centers within the SiO{sub 2} interfacial layer. This implies charge exchange between OIDs within HfO{sub 2} and the O-deficient silicon centers within the SiO{sub 2} interfacial layer are very important for controlling the radiation-induced trapped charge in HfO{sub 2} dielectric stacks.

Lauer, J. L.; Shohet, J. L. [Department of Electrical and Computer Engineering and Plasma Processing and Technology Laboratory, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Nishi, Y. [Stanford University, Stanford, California 94305 (United States)

2009-04-20T23:59:59.000Z

268

Method for producing a borohydride  

DOE Patents [OSTI]

A method for producing a borohydride is described and which includes the steps of providing a source of borate; providing a material which chemically reduces the source of the borate to produce a borohydride; and reacting the source of borate and the material by supplying heat at a temperature which substantially effects the production of the borohydride.

Kong, Peter C. (Idaho Falls, ID)

2008-09-02T23:59:59.000Z

269

Method of producing molybdenum-99  

SciTech Connect (OSTI)

Method of producing molybdenum-99, comprising accelerating ions by means of an accelerator; directing the ions onto a metal target so as to generate neutrons having an energy of greater than 10 MeV; directing the neutrons through a converter material comprising techentium-99 to produce a mixture comprising molybdenum-99; and, chemically extracting the molybdenum-99 from the mixture.

Pitcher, Eric John

2013-05-28T23:59:59.000Z

270

Atomic scale observation of phase separation and formation of silicon clusters in Hf higk-{kappa} silicates  

SciTech Connect (OSTI)

Hafnium silicate films were fabricated by RF reactive magnetron sputtering technique. Fine microstructural analyses of the films were performed by means of high-resolution transmission electron microscopy and atom probe tomography. A thermal treatment of as-grown homogeneous films leads to a phase separation process. The formation of SiO{sub 2} and HfO{sub 2} phases as well as pure Si one was revealed. This latter was found to be amorphous Si nanoclusters, distributed uniformly in the film volume. Their mean diameter and density were estimated to be about 2.8 nm and (2.9 {+-} 0.4) x 10{sup 17} Si-ncs/cm{sup 3}, respectively. The mechanism of the decomposition process was proposed. The obtained results pave the way for future microelectronic and photonic applications of Hf-based high-{kappa} dielectrics with embedded Si nanoclusters.

Talbot, E.; Roussel, M.; Genevois, C.; Pareige, P. [Groupe de Physique des Materiaux (GPM), Universite et INSA de Rouen, UMR CNRS 6634, Av. de l'Universite, BP 12, 76801 Saint Etienne du Rouvray (France); Khomenkova, L.; Portier, X.; Gourbilleau, F. [Centre de Recherche sur les Ions, les Materiaux et la Photonique (CIMAP), CEA/CNRS/ENSICAEN/UCBN, 6 Bd. Marechal Juin, 14050 Caen Cedex 4 (France)

2012-05-15T23:59:59.000Z

271

Self-assembly of Ni nanocrystals on HfO{sub 2} and N-assisted Ni confinement for nonvolatile memory application  

SciTech Connect (OSTI)

We demonstrate memory property using Ni nanocrystals with mean diameter of 9 nm embedded in HfO{sub 2} high-k dielectric that are formed via a self-assembly process by sputtering and rapid thermal annealing. X-ray photoelectron spectroscopy shows that Ni penetrates into the 5 nm HfO{sub 2} after high temperature annealing above 800 deg. C in N{sub 2}. However, the diffusion is suppressed by N incorporation into HfO{sub 2} by NH{sub 3} annealing. Metal-oxide-semiconductor structures were fabricated with Ni nanocrystals embedded in HfO{sub 2}. An additional counterclockwise hysteresis of 2.1 V due to the charge trapping properties of the Ni nanocrystals was observed from a {+-}5 V sweep during capacitance-voltage electrical measurement.

Tan, Zerlinda; Samanta, S.K.; Yoo, Won Jong; Lee, Sungjoo [Silicon Nano Device Laboratory, Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore)

2005-01-03T23:59:59.000Z

272

First in-beam observation of excited states in {sup 156}{sub 72}Hf{sub 84} using the recoul-decay tagging method  

SciTech Connect (OSTI)

Excited states in the proton rich nuclide {sup 156}{sub 72}Hf{sub 84} were observed for the first time using the {sup 102}({sup 58}Ni, 2p2n){sup 156}Hf reaction at 270 MeV. Gamma rays were detected with the AYEBALL array of Compton suppressed Ge detectors, placed in front of the Fragment Mass Analyzer, and were assigned to individual reaction charmers using the Recoil-Decay Tagging Method. Prompt {gamma}-ray cascades were associated with the alpha decay of both the ground state and the 8{sup +} isomeric state in {sup 156}Hf. The level scheme constructed for {sup 156}Hf is compared with level schemes of lighter even-even N=84 isotones and is discussed within the framework of the Shell Model.

Seweryniak, D.; Ahmad, H.; Amro, D.J. [and others

1996-12-31T23:59:59.000Z

273

Solvated Electrons in Very Small Clusters of Polar Molecules: (HF)(3)(-): art. no. 143001  

SciTech Connect (OSTI)

A cluster of polar molecules can host an excess electron in at least two ways. First, the excess electron can be tethered to the cluster by its interaction with the cluster?s dipole moment. , Second, the electron can localize inside the cluster, bulk analogs being the hydrated and ammoniated electrons. - While the structural reorganization of the cluster, due to attachment of an excess electron, is typically small for dipole-bound electrons (dbe), it is usually quite significant for''solvated electrons'' (se), since the solvation occurs at the expense of breaking of pre-existing hydrogen bonds. The se structures, however, provide more contact interactions between the polar molecules and the excess electron. For these reasons, it is often assumed that dbe's dominate for small polar clusters, whereas large clusters form se's. Here we show that dbe's and se's coexist in as small a cluster as (HF)3-. The stability of these anions with respect to the neutral cluster results not only from the excess electron binding energy but also from favorable entropic effects, which reflect the greater ''floppiness'' of the anionic structures.

Gutowski, Maciej S. (BATTELLE (PACIFIC NW LAB)); Hall, C (Arizona, University Of); Adamowicz, L (Arizona, University Of); Hendricks, J.H. (Johns Hopkins Univ); De Clercq, Helen (Howard University); Lyapustina, S.A. (Johns Hopkins Univ); Nilles, J.M. (Johns Hopkins Univ); Xu, S.J. (Johns Hopkins Univ); Bowen Jr., K.H. (Johns Hopkins Univ)

2001-12-01T23:59:59.000Z

274

Temperature dependent structural, optical and hydrophobic properties of sputtered deposited HfO{sub 2} films  

SciTech Connect (OSTI)

Hafnium oxide being high-k dielectric has been successfully utilized in electronic and optical applications. Being thermodynamically stable and having good mechanical strength, it can be used as a protective coating for outdoor HV insulators which are suffering from surface flashover problem due to contamination. In this paper, we are investigating the effect of substrate temperature on structural, optical and hydrophobic properties of hafnium oxide coating deposited over glass insulators by DC magnetron sputtering. X-ray diffraction is applied to determine the crystalline phase and crystallite size of the film. The morphology of the samples is examined using atomic force microscopy. The optical properties are studied using UV-vis-NIR spectrophotometer. The wettability of the film is investigated using contact angle meter. The thickness is measured using surface profilometer and verified through optical data. The relationship between substrate temperature with grain size, roughness, refractive index, and hydrophobicity is manifested. The maximum contact angle for HfO{sub 2} film was found to be 106° at 400°C.

Dave, V. [Department of Electrical Engineering, IIT Roorkee (India); Institute Instrumentation Centre, IIT Roorkee (India); Dubey, P.; Chandra, R. [Institute Instrumentation Centre, IIT Roorkee (India); Gupta, H. O. [Department of Electrical Engineering, IIT Roorkee (India)

2014-01-28T23:59:59.000Z

275

Memory functions of nanocrystalline cadmium selenide embedded ZrHfO high-k dielectric stack  

SciTech Connect (OSTI)

Metal-oxide-semiconductor capacitors made of the nanocrystalline cadmium selenide nc-CdSe embedded Zr-doped HfO{sub 2} high-k stack on the p-type silicon wafer have been fabricated and studied for their charge trapping, detrapping, and retention characteristics. Both holes and electrons can be trapped to the nanocrystal-embedded dielectric stack depending on the polarity of the applied gate voltage. With the same magnitude of applied gate voltage, the sample can trap more holes than electrons. A small amount of holes are loosely trapped at the nc-CdSe/high-k interface and the remaining holes are strongly trapped to the bulk nanocrystalline CdSe site. Charges trapped to the nanocrystals caused the Coulomb blockade effect in the leakage current vs. voltage curve, which is not observed in the control sample. The addition of the nanocrystals to the dielectric film changed the defect density and the physical thickness, which are reflected on the leakage current and the breakdown voltage. More than half of the originally trapped holes can be retained in the embedded nanocrystals for more than 10 yr. The nanocrystalline CdSe embedded high-k stack is a useful gate dielectric for this nonvolatile memory device.

Lin, Chi-Chou; Kuo, Yue [Thin Film Nano and Microelectronics Research Laboratory, Artie McFerrin Department of Chemical Engineering, Texas A and M University, College Station, Texas 77843-3122 (United States)

2014-02-28T23:59:59.000Z

276

Features of the band structure and conduction mechanisms in the n-HfNiSn semiconductor heavily doped with Ru  

SciTech Connect (OSTI)

The crystal and electronic structure and energy and kinetic properties of the n-HfNiSn semiconductor heavily doped with a Ru acceptor impurity are investigated in the temperature and Ru concentration ranges T = 80–400 K and N{sub A}{sup Ru} ? 9.5 × 10{sup 19}?5.7 × 10{sup 20} cm{sup ?3} (x = 0–0.03), respectively. The mechanism of structural-defect generation is established, which changes the band gap and degree of compensation of the semiconductor and consists in the simultaneous concentration reduction and elimination of donor structural defects by means of the displacement of ?1% of Ni atoms from the Hf (4a) positions, the generation of acceptor structural defects upon the substitution of Ru atoms for Ni atoms in the 4c positions, and the generation of donor defects in the form of vacancies in the Sn (4b) positions. The calculated electronic structure of HfNi{sub 1?x}Ru{sub x}Sn is consistent with the experiment. The results obtained are discussed within the Shklovsky-Efros model for a heavily doped and compensated semiconductor.

Romaka, V. A., E-mail: vromaka@polynet.lviv.ua [National Academy of Sciences of Ukraine, Pidstrygach Institute for Applied Problems in Mechanics and Mathematics (Ukraine); Rogl, P. [Universität Wien, Institut für Physikalische Chemie (Austria); Romaka, V. V. [National University Lvivska Politekhnika (Ukraine); Stadnyk, Yu. V. [Ivan Franko National University of Lviv (Ukraine); Korzh, R. O.; Krayovskyy, V. Ya. [National University Lvivska Politekhnika (Ukraine); Horyn, A. M. [Ivan Franko National University of Lviv (Ukraine)

2014-12-15T23:59:59.000Z

277

Highly efficient dye-sensitized solar cells based on HfO{sub 2} modified TiO{sub 2} electrodes  

SciTech Connect (OSTI)

Graphical abstract: Display Omitted Highlights: ? HfO{sub 2} has been used to modify TiO{sub 2} electrodes in dye sensitized solar cells. ? HfO{sub 2} layer increases the dye adsorption. ? Diffusion coefficient (D{sub e}) and lifetime (?{sub e}) of the photoelectrons were increased. ? Solar cell efficiency (?) was greatly improved from 5.67 to 9.59%. -- Abstract: In this article, we describe the use of hafnium oxide (HfO{sub 2}) as a new and efficient blocking layer material to modify TiO{sub 2} electrodes in dye sensitized solar cells. Different thicknesses of HfO{sub 2} over-layers were prepared by simple dip coating from two different precursors and their effects on the performance of DSSCs were studied. The HfO{sub 2} modification remarkably increases dye adsorption, resulting from the fact that the surface of HfO{sub 2} is more basic than that of TiO{sub 2}. Furthermore, the HfO{sub 2} coating demonstrated increased diffusion coefficient (D{sub e}) and lifetime (?{sub e}) of the photoelectrons, indicating the improved retardation of the back electron transfer, which increases short-circuit current (J{sub sc}) and open-circuit voltage (V{sub oc}). Thereby, the photo conversion efficiency (?) of the solar cell was greatly improved from 5.67 to 9.59% (an improvement of 69.02%) as the HfO{sub 2} layer was coated over TiO{sub 2} films.

Ramasamy, Parthiban [Department of Chemistry and GETRC, Kongju National University, 182 Singkwan, Kongju, Chungnam 314-701 (Korea, Republic of)] [Department of Chemistry and GETRC, Kongju National University, 182 Singkwan, Kongju, Chungnam 314-701 (Korea, Republic of); Kang, Moon-Sung; Cha, Hyeon-Jung [Department of Environmental Engineering, Sangmyung University, 300 Anseo-dong, Dongnam-gu, Cheonan-si, Chungnam 330-720 (Korea, Republic of)] [Department of Environmental Engineering, Sangmyung University, 300 Anseo-dong, Dongnam-gu, Cheonan-si, Chungnam 330-720 (Korea, Republic of); Kim, Jinkwon, E-mail: jkim@kongju.ac.kr [Department of Chemistry and GETRC, Kongju National University, 182 Singkwan, Kongju, Chungnam 314-701 (Korea, Republic of)] [Department of Chemistry and GETRC, Kongju National University, 182 Singkwan, Kongju, Chungnam 314-701 (Korea, Republic of)

2013-01-15T23:59:59.000Z

278

Methods of producing cesium-131  

DOE Patents [OSTI]

Methods of producing cesium-131. The method comprises dissolving at least one non-irradiated barium source in water or a nitric acid solution to produce a barium target solution. The barium target solution is irradiated with neutron radiation to produce cesium-131, which is removed from the barium target solution. The cesium-131 is complexed with a calixarene compound to separate the cesium-131 from the barium target solution. A liquid:liquid extraction device or extraction column is used to separate the cesium-131 from the barium target solution.

Meikrantz, David H; Snyder, John R

2012-09-18T23:59:59.000Z

279

Cellulase producing microorganism ATCC 55702  

DOE Patents [OSTI]

Bacteria which produce large amounts of cellulase--containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualifies for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques. 5 figs.

Dees, H.C.

1997-12-30T23:59:59.000Z

280

Microorganisms for producing organic acids  

DOE Patents [OSTI]

Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

Pfleger, Brian Frederick; Begemann, Matthew Brett

2014-09-30T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Cellulase producing microorganism ATCC 55702  

DOE Patents [OSTI]

Bacteria which produce large amounts of cellulase--containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualifies for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques.

Dees, H. Craig (Lenoir City, TN)

1997-01-01T23:59:59.000Z

282

Polar intermetallic compounds of the silicon and arsenic family elements and their ternary hydrides and fluorides  

SciTech Connect (OSTI)

An investigation has been made on the effects of hydrogen and fluoride in the solid state chemistry of alkaline-earth and divalent rare-earth metal pnictide (Pn) and tetrelide (Tt) phases A{sub 5}(Pn,Tt,){sub 3}Z{sub x}, where A = Ca, Sr, Ba, Sm, Eu, Yb; Pn = As, Sb, Bi; Tt = Si, Ge, Sn, Pb and Z = H, F. Several trivalent rare-earth-metal pnictides, RE{sub 5}Pn{sub 3} (RE = Y, La, Gd, Tb, Dy, Ho, Er, Tm) and alkaline-earth-metal trielides, A{sub 5}Tr{sub 3}Z{sub x} (Tr = Ga, In, Tl) have been included in an effort to complete observed structural trends. Two main experimental techniques were followed throughout this work, (a) reactions in absence of hydrogen or under continuous high vacuum, and (b) reactions with binary metal hydrides, AH{sub x}, in closed containers. The results demonstrate that all the phases reported with the {beta}-Yb{sub 5}Sb{sub 3}-type structure in the A{sub 5}Pn{sub 3} systems are hydrogen-stabilized compounds. Reactions in absence of hydrogen lead to compounds with the Mn{sub 5}Si{sub 3}-type structure. The structure type {beta}-Yb{sub 5}Sb{sub 3} (= Ca{sub 5}SB{sub 3}F) was found to be characteristic of ternary systems and inaccurately associated with phases that form in the Y{sub 5}Bi{sub 3}-type. A new series of isomorphous Zintl compounds with the Ca{sub 16}Sb{sub 11}-type structure were prepared and studied as well. All the alkaline-earth-metal tetrelides, A{sub 5}Tt{sub 3}, that crystallize in the Cr{sub 5}B{sub 3}-type structure can be interstitially derivatized by hydrogen or fluoride. Binary and ternary compounds were characterized by Guinier powder patterns, single crystal X-ray and powder neutron diffraction techniques. In an effort to establish property-structure relationships, electrical resistivity and magnetic measurements were performed on selected systems, and the results were explained in terms of the Zintl concepts, aided by extended Hueckel band calculations.

Leon-Escamilla, E.A.

1996-10-17T23:59:59.000Z

283

Hydrothermal synthesis of new rare earth silicate fluorides: A novel class of polar materials  

SciTech Connect (OSTI)

Polar crystals provide an interesting avenue for materials research both in the structures they form and the properties they possess. This work describes the hydrothermal synthesis and structural characterization of three novel silicate fluorides. Compound (1), LiY{sub 3}(SiO{sub 4}){sub 2}F{sub 2} crystallizes in space group C2/c, with a=17.651(4) A, b=4.8868(10) A, c=11.625(2) A and {beta}=131.13(3) Degree-Sign . BaY{sub 2}(Si{sub 2}O{sub 7})F{sub 2} (2) crystallizes in space group P-1, with a=5.1576(10) A, b=6.8389(14) A, c=11.786(2) A, {alpha}=93.02(3) Degree-Sign , {beta}=102.05(3) Degree-Sign and {gamma}=111.55(3) Degree-Sign . Finally, the structure of Ba{sub 2}Y{sub 3}(SiO{sub 4}){sub 2}F{sub 5} (3) was determined in the polar orthorhombic space group Pba2, having unit cell parameters a=8.8864(18) A, b=12.764(3) A and c=5.0843(10) A. The structures are compared based on their building blocks and long range polarities. Aligned silicate tetrahedra segregated into a single layer in (3) impart the observed polarity. - Graphical abstract: The polar structure of Ba{sub 2}Y{sub 3}(SiO{sub 4}){sub 2}F{sub 5}. Highlights: Black-Right-Pointing-Pointer Natural yttrium silicate fluoride minerals are briefly reviewed. Black-Right-Pointing-Pointer The synthesis and structures of LiY{sub 3}(SiO{sub 4}){sub 2}F{sub 2}, BaY{sub 2}(Si{sub 2}O{sub 7})F{sub 2} and Ba{sub 2}Y{sub 3}(SiO{sub 4}){sub 2}F{sub 5} are discussed. Black-Right-Pointing-Pointer Ba{sub 2}Y{sub 3}(SiO{sub 4}){sub 2}F{sub 5} crystallizes in the polar space group Pba2. Black-Right-Pointing-Pointer Polarity occurs primarily through aligned silicate tetrahedra in a segregated layer.

McMillen, Colin D., E-mail: cmcmill@clemson.edu [Department of Chemistry and Center for Optical Materials Science and Engineering Technologies (COMSET), Clemson University, 485 H.L. Hunter Laboratories, Clemson, SC 29634 (United States); Emirdag-Eanes, Mehtap, E-mail: mehtapemirdag@iyte.edu.tr [Department of Chemistry, Izmir Institute of Technology, Gulbahce koyu, Urla, Izmir 35430 (Turkey)] [Department of Chemistry, Izmir Institute of Technology, Gulbahce koyu, Urla, Izmir 35430 (Turkey); Stritzinger, Jared T., E-mail: jstritz@clemson.edu [Department of Chemistry and Center for Optical Materials Science and Engineering Technologies (COMSET), Clemson University, 485 H.L. Hunter Laboratories, Clemson, SC 29634 (United States); Kolis, Joseph W., E-mail: kjoseph@clemson.edu [Department of Chemistry and Center for Optical Materials Science and Engineering Technologies (COMSET), Clemson University, 485 H.L. Hunter Laboratories, Clemson, SC 29634 (United States)

2012-11-15T23:59:59.000Z

284

The rate constant for radiative association of HF: Comparing quantum and classical dynamics  

SciTech Connect (OSTI)

Radiative association for the formation of hydrogen fluoride through the A{sup 1}? ? X{sup 1}?{sup +} and X{sup 1}?{sup +} ? X{sup 1}?{sup +} transitions is studied using quantum and classical dynamics. The total thermal rate constant is obtained for temperatures from 10 K to 20 000 K. Agreement between semiclassical and quantum approaches is observed for the A{sup 1}? ? X{sup 1}?{sup +} rate constant above 2000 K. The agreement is explained by the fact that the corresponding cross section is free of resonances for this system. At temperatures below 2000 K we improve the agreement by implementing a simplified semiclassical expression for the rate constant, which includes a quantum corrected pair distribution. The rate coefficient for the X{sup 1}?{sup +} ? X{sup 1}?{sup +} transition is calculated using Breit–Wigner theory and a classical formula for the resonance and direct contributions, respectively. In comparison with quantum calculations the classical formula appears to overestimate the direct contribution to the rate constant by about 12% for this transition. Below about 450 K the resonance contribution is larger than the direct, and above that temperature the opposite holds. The biggest contribution from resonances is at the lowest temperature in the study, 10 K, where it is more than four times larger than the direct. Below 1800 K the radiative association rate constant due to X{sup 1}?{sup +} ? X{sup 1}?{sup +} transitions dominates over A{sup 1}? ? X{sup 1}?{sup +}, while above that temperature the situation is the opposite.

Gustafsson, Magnus, E-mail: magngu@chem.gu.se; Monge-Palacios, M.; Nyman, Gunnar [Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg (Sweden)] [Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg (Sweden)

2014-05-14T23:59:59.000Z

285

Structure and dielectric properties of La{sub x}Hf{sub (1?x)}O{sub y} thin films: The dependence of components  

SciTech Connect (OSTI)

Graphical abstract: - Highlights: • La{sub x}Hf{sub (1?x)}O{sub y} thin films were grown by pulse laser deposition method. • The thin film with 10% La/(La + Hf) atom ratio forms a cubic HfO{sub 2} phase. • The amorphous thin films due to more La introduced have almost same local structure. • The main infrared phonon modes move to lower frequency for the amorphous thin films. • The static dielectric constants of the amorphous thin films increase with La content. - Abstract: La{sub x}Hf{sub (1?x)}O{sub y} (x = 0, 0.1, 0.3, 0.5, 0.7, y=2?(1/2)x) thin films were grown by pulsed laser deposition (PLD) method. The component dependence of the structure and vibration properties of these thin films is studied by combining X-ray diffraction, X-ray absorption fine structure (XAFS) and infrared spectroscopy. The thin film with 10% La/(La + Hf) atom ratio forms a cubic HfO{sub 2} phase and it has the largest static dielectric constant. More La atoms introduced cause amorphous phase formed and the static dielectric constants increase with the La content. Although XAFS indicates that these amorphous thin films have almost same local structures, the infrared phonon modes with most contribution to the static dielectric constant move to lower frequency, which results in the component dependence of the dielectric constant.

Qi, Zeming, E-mail: zmqi@ustc.edu.cn [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029 (China); Cheng, Xuerui [Department of Technology and Physics, Zhengzhou University of Light Industry, Zhengzhou, Henan 450002 (China); Zhang, Guobin [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029 (China); Li, Tingting [Institute of Microelectronics of Chinese Academy of Science, Beijing 100029 (China); Wang, Yuyin; Shao, Tao; Li, Chengxiang; He, Bo [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029 (China)

2013-07-15T23:59:59.000Z

286

Thermal stability of Al- and Zr-doped HfO{sub 2} thin films grown by direct current magnetron sputtering  

SciTech Connect (OSTI)

Ultrathin HfO{sub 2} dielectric films doped with Al and Zr were grown on p-type Si(100) substrates by dc magnetron sputtering, and their microstructural and electrical properties were examined. Compositions and chemical states of the dielectric films were analyzed by Rutherford backscattering spectrometry and x-ray photoelectron spectroscopy. The HfO{sub 2} films doped with Zr were crystallized even from the as-deposited state, however, the crystallization temperature of the HfO{sub 2} film doped with 16% Al{sub 2}O{sub 3} was delayed up to 900 deg. C. As the annealing temperature increases, high-resolution transmission electron microscopy analyses of all doped HfO{sub 2} films showed an increase of the interfacial layer thickness due to the diffusion of small partial pressure of oxygen in annealing ambient. Our results also showed that the addition of Al{sub 2}O{sub 3} to 14% is not useful for blocking the oxygen diffusion through the (HfO{sub 2}){sub 0.86}(Al{sub 2}O{sub 3}){sub 0.14} film. From the capacitance-voltage measurements, the dielectric constants of the Al- and Zr-doped HfO{sub 2} thin films were measured to be 18.7 and 7.6, respectively.

Hong, Yeong-Eui; Kim, Yong-Seok; Do, Kihoon; Lee, Dongwon; Ko, Dae-Hong; Ku, Ja-Hum; Kim, Hyoungsub [Department of Ceramic Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-749 (Korea, Republic of); Semiconductor R and D Division, Samsung Electronics Co, Ltd., San no. 24, Nongseo-Ri, Kiheung-Eup, Yongin-City, Kyunggi-Do 449-711 (Korea, Republic of); Department of Advanced Materials Engineering, Sungkyunkwan University, 300 Chunchun-Dong, Jangan-Ku, Suwon 440-746 (Korea, Republic of)

2005-09-15T23:59:59.000Z

287

Methods of producing transportation fuel  

DOE Patents [OSTI]

Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method for producing transportation fuel is described herein. The method for producing transportation fuel may include providing formation fluid having a boiling range distribution between -5.degree. C. and 350.degree. C. from a subsurface in situ heat treatment process to a subsurface treatment facility. A liquid stream may be separated from the formation fluid. The separated liquid stream may be hydrotreated and then distilled to produce a distilled stream having a boiling range distribution between 150.degree. C. and 350.degree. C. The distilled liquid stream may be combined with one or more additives to produce transportation fuel.

Nair, Vijay (Katy, TX); Roes, Augustinus Wilhelmus Maria (Houston, TX); Cherrillo, Ralph Anthony (Houston, TX); Bauldreay, Joanna M. (Chester, GB)

2011-12-27T23:59:59.000Z

288

The transported entropies of ions in solid state fluorides and beta-alumina  

SciTech Connect (OSTI)

The technical relevance of reversible heat effects is discussed with reference to high temperature batteries and electrolysis systems. The transported entropies of Na{sup +} in solid state mixtures of NaF and Na{sub 3}AlF{sub 6} are presented. The transported entropies are S{sup *cry}{sub Na{sup +}} = 140 {+-} 7 J K{sup {minus}1} mol{sup {minus}1} for cryolite, S{sup *NaF}{sub Na{sup +}} = 81 {+-} 8 J K{sup {minus}1} mol{sup {minus}1} for sodium fluoride and S{sup *{beta}}{sub Na{sup +}} = 60 {+-} 5 J K{sup {minus}1} mol{sup {minus}1} for sodium {beta}{double_prime}-alumina at the temperature range 380--500 C. The value obtained for sodium in the solid cryolite is higher than transported entropy of Na{sup +} in other solid sodium conductors and makes the authors predict that the transported entropy for Na{sup +} in the molten electrolyte mixture for aluminum production is substantial, and that so are the reversible heat effects in the aluminum electrolysis cell.

Sharivker, V.S.; Ratkje, S.K. [Univ. of Trondheim (Norway)

1996-10-01T23:59:59.000Z

289

Low-level fluoride trapping studies experimental work for computer modeling program  

SciTech Connect (OSTI)

The material presented in this report involved experimental work performed to assist in determining the constants for a computer modeling program being developed by Production Engineering for use in trap design. Included in this study is bed distribution studies to define uranium loading on alumina (Al/sub 2/O/sub 3/) and sodium fluoride (NaF) with respect to bed zones. A limited amount of work was done on uranium penetration into NaF pellets. Only the experimental work is reported here; Production Engineering will use this data to develop constants for the computer model. Some of the significant conclusions are: NaF has more capacity to load UF/sub 6/, but Al/sub 2/O/sub 3/ distributes the load more equally; velocity, system pressure, and operating temperature influence uranium loading; and in comparative tests NaF had a loading of 25%, while Al/sub 2/O/sub 3/ was 13%. 2 refs., 10 figs., 5 tabs.

Russell, R.G.

1988-11-21T23:59:59.000Z

290

Energy-Efficient, High-Color-Rendering LED Lamps Using Oxyfluoride and Fluoride Phosphors  

SciTech Connect (OSTI)

LED lamps using phosphor downconversion can be designed to replace incandescent or halogen sources with a 'warm-white' correlated color temperature (CCT) of 2700-3200 K and a color rendering index (CRI) greater than 90. However, these lamps have efficacies of {approx}70% of standard 'cool-white' LED packages (CCT = 4500-6000 K; CRI = 75-80). In this report, we describe structural and luminescence properties of fluoride and oxyfluoride phosphors, specifically a (Sr,Ca){sub 3}(Al,Si)O{sub 4}(F,O):Ce{sup 3+} yellow-green phosphor and a K{sub 2}TiF{sub 6}:Mn{sup 4+} red phosphor, that can reduce this gap and therefore meet the spectral and efficiency requirements for high-efficacy LED lighting. LED lamps with a warm-white color temperature (3088 K), high CRI (90), and an efficacy of {approx}82 lm/W are demonstrated using these phosphors. This efficacy is {approx}85% of comparable cool-white lamps using typical Y{sub 3}Al{sub 5}O{sub 12}:Ce{sup 3+}-based phosphors, significantly reducing the efficacy gap between warm-white and cool-white LED lamps that use phosphor downconversion.

Setlur, A.; Radkov, E; Henderson, C; Her, J; Srivastava, A; Karkada, N; Kishore, M; Kumar, N; Aesram, D; et al.

2010-01-01T23:59:59.000Z

291

Compatibility of strontium-90 fluoride with containment materials at elevated temperatures  

SciTech Connect (OSTI)

The use of /sup 90/SrF/sub 2/ as a heat-source fuel requires that the /sup 90/Sr be adequately contained during heat-source service. A program for determining the compatibility of /sup 90/SrF/sub 2/ with containment materials at heat-source operating temperatures is described. These compatibility studies included: initial and supplemental screening tests; WESF /sup 90/SrF/sub 2/ capsule demonstration tests; thermal gradient test; and long-term tests. TZM, Haynes Alloy 25, and Hastelloy C-276 were the three materitals selected for evaluation at 600/sup 0/, 800/sup 0/ and 1000/sup 0/C for periods up to 30,000 h. Results showed that all three alloys suffered substantial attack when exposed to the /sup 90/SrF/sub 2/, although the TZM was more resistant to attack than the Hastelloy C-276 and Haynes Alloy 25. The latter two alloys appeared to provide about equal resistance to fluoride attack for exposures longer than about 12,000 h. Attack of the alloys tested by the /sup 90/SrF/sub 2/ was due primarily to impurities.

Fullam, H.T.

1981-08-01T23:59:59.000Z

292

The integration of Human Factors (HF) in the SAR process training course text  

SciTech Connect (OSTI)

This text provides the technical basis for a two-day course on human factors (HF), as applied to the Safety Analysis Report (SAR) process. The overall objective of this text and course is to: provide the participant with a working knowledge of human factors-related requirements, suggestions for doing a human safety analysis applying a graded approach, and an ability to demonstrate using the results of the human safety analysis, that human factors elements as defined by DOE (human factors engineering, procedures, training, oversight, staffing, qualifications), can support wherever necessary, nuclear safety commitments in the SAR. More specifically, the objectives of the text and course are: (1) To provide the SAR preparer with general guidelines for doing HE within the context of a graded approach for the SAR; (2) To sensitize DOE facility managers and staff, safety analysts and SAR preparers, independent reviewers, and DOE reviewers and regulators, to DOE Order 5480.23 requirements for HE in the SAR; (3) To provide managers, analysts, reviewers and regulators with a working knowledge of HE concepts and techniques within the context of a graded approach for the SAR, and (4) To provide SAR managers and DOE reviewers and regulators with general guidelines for monitoring and coordinating the work of preparers of HE inputs throughout the SAR process, and for making decisions regarding the safety relevance of HE inputs to the SAR. As a ready reference for implementing the human factors requirements of DOE Order 5480.22 and DOE Standard 3009-94, this course text and accompanying two-day course are intended for all persons who are involved in the SAR.

Ryan, T.G.

1995-03-01T23:59:59.000Z

293

Current Producers of Developed Grasses Producers Contact Phone Number  

E-Print Network [OSTI]

Rod 979-543-0121 Trinity Turf Nursery* Doug O'Conner 800-290-8873 Wharton Turfgrass Jimmy Kocurek 979 Turfgrass Jimmy Kocurek 979-532-4340 Wittig Grass Farms Allan Wittig 979-657-4496 Diamond Producers Contact Turfgrass Jimmy Kocurek 979-532-4340 Winstead Turf Farms* (AR, MS, TN) Bobby Winstead 800-624-8873 Wittig

294

Thermal response of Ru electrodes in contact with SiO{sub 2} and Hf-based high-k gate dielectrics  

SciTech Connect (OSTI)

A systematic experimental evaluation of the thermal stability of Ru metal gate electrodes in direct contact with SiO{sub 2} and Hf-based dielectric layers was performed and correlated with electrical device measurements. The distinctly different interfacial reactions in the Ru/SiO{sub 2}, Ru/HfO{sub 2}, and Ru/HfSiO{sub x} film systems were observed through cross-sectional high-resolution transmission electron microscopy, high angle annular dark field scanning transmission electron microscopy with electron-energy-loss spectra, and energy dispersive x-ray spectra analysis. Ru interacted with SiO{sub 2}, but remained stable on HfO{sub 2} at 1000 deg. C. The onset of Ru/SiO{sub 2} interfacial interactions is identified via silicon substrate pitting possibly from Ru diffusion into the dielectric in samples exposed to a 900 deg. C/10-s anneal. The dependence of capacitor device degradation with decreasing SiO{sub 2} thickness suggests Ru diffuses through SiO{sub 2}, followed by an abrupt, rapid, nonuniform interaction of ruthenium silicide as Ru contacts the Si substrate. Local interdiffusion detected on Ru/HfSiO{sub x} samples may be due to phase separation of HfSiO{sub x} into HfO{sub 2} grains within a SiO{sub 2} matrix, suggesting that SiO{sub 2} provides a diffusion pathway for Ru. Detailed evidence consistent with a dual reaction mechanism for the Ru/SiO{sub 2} system at 1000 deg. C is presented.

Wen, H.-C.; Lysaght, P.; Alshareef, H.N.; Huffman, C.; Harris, H.R.; Choi, K.; Senzaki, Y.; Luan, H.; Majhi, P.; Lee, B.H.; Campin, M. J.; Foran, B.; Lian, G.D.; Kwong, D.-L. [SEMATECH, 2706 Montopolis Drive, Austin, Texas 78741(United States); University of Texas at Austin, Pickle Research Campus-Microelectronics and Engineering Research (PRC-MER) Building 2.606A/R9950, Austin, Texas 78712 (United States); SEMATECH, 2706 Montopolis Drive, Austin, Texas 78741 (United States); Advanced Technology Development Facility (ATDF) Inc., 2706 Montopolis Drive, Austin, Texas 78741 (United States); University of Texas at Austin, Pickle Research Campus-Microelectronics and Engineering Research (PRC-MER) Building 2.606A/R9950, Austin, Texas 78712 (United States)

2005-08-15T23:59:59.000Z

295

Additive manufacturing method of producing  

E-Print Network [OSTI]

Additive manufacturing method of producing silver or copper tracks on polyimide film Problem/stripping) using an additive process support by a novel bio- degradable photo-initiator package. technology. Building on previous work by Hoyd- Gigg Ng et al. [1,2], Heriot-Watt has developed an additive film

Painter, Kevin

296

Process for producing chalcogenide semiconductors  

DOE Patents [OSTI]

A process for producing chalcogenide semiconductor material is disclosed. The process includes forming a base metal layer and then contacting this layer with a solution having a low pH and containing ions from at least one chalcogen to chalcogenize the layer and form the chalcogenide semiconductor material.

Noufi, R.; Chen, Y.W.

1985-04-30T23:59:59.000Z

297

Electrically Conductive Bacterial Nanowires Produced by Shewanella...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Conductive Bacterial Nanowires Produced by Shewanella Oneidensis Strain MR-1 and Other Microorganisms . Electrically Conductive Bacterial Nanowires Produced by Shewanella...

298

Preliminary requirements for a Fluoride Salt-Cooled High-Temperature Test Reactor (FHTR)  

SciTech Connect (OSTI)

A Fluoride Salt-Cooled High-Temperature Test Reactor (FHTR) design is being developed at MIT to provide the first demonstration and test of a salt-cooled reactor using high-temperature fuel. The first step is to define the requirements. The top level requirements are (1) provide the confidence that a larger demonstration reactor is warranted and (2) develop the necessary data for a larger-scale reactor. Because requirements will drive the design of the FHTR, a significant effort is being undertaken to define requirements and understand the tradeoffs that will be required for a practical design. The preliminary requirements include specifications for design parameters and necessary tests of major reactor systems. Testing requirements include demonstration of components, systems, and procedures for refueling, instrumentation, salt temperature control to avoid coolant freezing, salt chemistry and volume control, tritium monitoring and control, and in-service inspection. Safety tests include thermal hydraulics, neutronics - including intrinsic core shutdown mechanisms such as Doppler feedback - and decay heat removal systems. Materials and coolant testing includes fuels (including mechanical wear and fatigue) and system corrosion behavior. Preliminary analysis indicates a thermal power output below 30 MW, an initial core using pebble-bed or prismatic-block fuel, peak outlet temperatures of at least 700 deg. C, and use of FLi{sup 7}Be ({sup 7}LiF-BeF{sub 2}) coolant. The option to change-out the reactor core, fuel type, and major components is being investigated. While the FHTR will be used for materials testing, its primary mission is as a reactor system performance test to enable the design and licensing of a FHR demonstration power reactor. (authors)

Massie, M.; Forsberg, C.; Forget, B. [Dept. of Nuclear Science and Engineering, Massachusetts Inst. of Technology, Cambridge, MA 02139 (United States); Hu, L. W. [Nuclear Reactor Laboratory, Massachusetts Inst. of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)

2012-07-01T23:59:59.000Z

299

Structure-Directing Roles and Interactions of Fluoride and Organocations with Siliceous Zeolite Frameworks  

SciTech Connect (OSTI)

Interactions of fluoride anions and organocations with crystalline silicate frameworks are shown to depend subtly on the architectures of the organic species, which significantly influence the crystalline structures that result. One- and two-dimensional (2D) {sup 1}H, {sup 19}F, and {sup 29}Si nuclear magnetic resonance (NMR) spectroscopy measurements establish distinct intermolecular interactions among F{sup -} anions, imidazolium structure-directing agents (SDA{sup +}), and crystalline silicate frameworks for as-synthesized siliceous zeolites ITW and MTT. Different types and positions of hydrophobic alkyl ligands on the imidazolium SDA{sup +} species under otherwise identical zeolite synthesis compositions and conditions lead to significantly different interactions between the F{sup -} and SDA{sup +} ions and the respective silicate frameworks. For as-synthesized zeolite ITW, F{sup -} anions are established to reside in the double-four-ring (D4R) cages and interact strongly and selectively with D4R silicate framework sites, as manifested by their strong {sup 19}F{sup 29}Si dipolar couplings. By comparison, for as-synthesized zeolite MTT, F{sup -} anions reside within the 10-ring channels and interact relatively weakly with the silicate framework as ion pairs with the SDA{sup +} ions. Such differences manifest the importance of interactions between the imidazolium and F{sup -} ions, which account for their structure-directing influences on the topologies of the resulting silicate frameworks. Furthermore, 2D {sup 29}Si{l_brace}{sup 29}Si{r_brace} double-quantum NMR measurements establish {sup 29}Si-O-{sup 29}Si site connectivities within the as-synthesized zeolites ITW and MTT that, in conjunction with synchrotron X-ray diffraction analyses, establish insights on complicated order and disorder within their framework structures.

Shayib, Ramzy M.; George, Nathan C.; Seshadri, Ram; Burton, Allen W.; Zones, Stacey I.; Chmelka, Bradley F. (UCSB); (Chevron ETC)

2012-02-06T23:59:59.000Z

300

Partial oxidation process for producing a stream of hot purified gas  

DOE Patents [OSTI]

A partial oxidation process is described for the production of a stream of hot clean gas substantially free from particulate matter, ammonia, alkali metal compounds, halides and sulfur-containing gas for use as synthesis gas, reducing gas, or fuel gas. A hydrocarbonaceous fuel comprising a solid carbonaceous fuel with or without liquid hydrocarbonaceous fuel or gaseous hydrocarbon fuel, wherein said hydrocarbonaceous fuel contains halides, alkali metal compounds, sulfur, nitrogen and inorganic ash containing components, is reacted in a gasifier by partial oxidation to produce a hot raw gas stream comprising H{sub 2}, CO, CO{sub 2}, H{sub 2}O, CH{sub 4}, NH{sub 3}, HCl, HF, H{sub 2}S, COS, N{sub 2}, Ar, particulate matter, vapor phase alkali metal compounds, and molten slag. The hot raw gas stream from the gasifier is split into two streams which are separately deslagged, cleaned and recombined. Ammonia in the gas mixture is catalytically disproportionated into N{sub 2} and H{sub 2}. The ammonia-free gas stream is then cooled and halides in the gas stream are reacted with a supplementary alkali metal compound to remove HCl and HF. Alkali metal halides, vaporized alkali metal compounds and residual fine particulate matter are removed from the gas stream by further cooling and filtering. The sulfur-containing gases in the process gas stream are then reacted at high temperature with a regenerable sulfur-reactive mixed metal oxide sulfur sorbent material to produce a sulfided sorbent material which is then separated from the hot clean purified gas stream having a temperature of at least 1000 F. 1 figure.

Leininger, T.F.; Robin, A.M.; Wolfenbarger, J.K.; Suggitt, R.M.

1995-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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301

Partial oxidation process for producing a stream of hot purified gas  

DOE Patents [OSTI]

A partial oxidation process for the production of a stream of hot clean gas substantially free from particulate matter, ammonia, alkali metal compounds, halides and sulfur-containing gas for use as synthesis gas, reducing gas, or fuel gas. A hydrocarbonaceous fuel comprising a solid carbonaceous fuel with or without liquid hydrocarbonaceous fuel or gaseous hydrocarbon fuel, wherein said hydrocarbonaceous fuel contains halides, alkali metal compounds, sulfur, nitrogen and inorganic ash containing components, is reacted in a gasifier by partial oxidation to produce a hot raw gas stream comprising H.sub.2, CO, CO.sub.2, H.sub.2 O, CH.sub.4, NH.sub.3, HCl, HF, H.sub.2 S, COS, N.sub.2, Ar, particulate matter, vapor phase alkali metal compounds, and molten slag. The hot raw gas stream from the gasifier is split into two streams which are separately deslagged, cleaned and recombined. Ammonia in the gas mixture is catalytically disproportionated into N.sub.2 and H.sub.2. The ammonia-free gas stream is then cooled and halides in the gas stream are reacted with a supplementary alkali metal compound to remove HCl and HF. Alkali metal halides, vaporized alkali metal compounds and residual fine particulate matter are removed from the gas stream by further cooling and filtering. The sulfur-containing gases in the process gas stream are then reacted at high temperature with a regenerable sulfur-reactive mixed metal oxide sulfur sorbent material to produce a sulfided sorbent material which is then separated from the hot clean purified gas stream having a temperature of at least 1000.degree. F.

Leininger, Thomas F. (Chino Hills, CA); Robin, Allen M. (Anaheim, CA); Wolfenbarger, James K. (Torrance, CA); Suggitt, Robert M. (Wappingers Falls, NY)

1995-01-01T23:59:59.000Z

302

EIS-0360: Depleted Uranium Oxide Conversion Product at the Portsmouth, Ohio Site  

Broader source: Energy.gov [DOE]

This site-specific EIS analyzes the construction, operation, maintenance, and decontamination and decommissioning of the proposed depleted uranium hexafluoride (DUF6) conversion facility at three alternative locations within the Paducah site; transportation of all cylinders (DUF6, enriched, and empty) currently stored at the East Tennessee Technology Park (ETTP) near Oak Ridge, Tennessee, to Portsmouth; construction of a new cylinder storage yard at Portsmouth (if required) for ETTP cylinders; transportation of depleted uranium conversion products and waste materials to a disposal facility; transportation and sale of the hydrogen fluoride (HF) produced as a conversion coproduct; and neutralization of HF to calcium fluoride and its sale or disposal in the event that the HF product is not sold.

303

IUPAC-NIST Solubility Data Series. 100. Rare Earth Metal Fluorides in Water and Aqueous Systems. Part 1. Scandium Group (Sc, Y, La)  

SciTech Connect (OSTI)

This work presents an assessment of solubility data for rare earth metal fluorides (generally of trivalent metals and of CeF{sub 4}) in water and in aqueous ternary systems. Compilations of all available experimental data are introduced for each rare earth metal fluoride with a corresponding critical evaluation. Every such evaluation contains a collection of all solubility results in water, a selection of suggested solubility data, and a brief discussion of the multicomponent systems. Because the ternary systems were seldom studied more than once, no critical evaluations of such data were possible. Only simple fluorides (no complexes or binary salts) are treated as the input substances in this report. The literature has been covered through the end of 2013.

Mioduski, Tomasz [Institute of Nuclear Chemistry and Technology, 03195 Warsaw (Poland); Gumi?ski, Cezary, E-mail: cegie@chem.uw.edu.pl [Department of Chemistry, University of Warsaw, 02093 Warsaw (Poland); Zeng, Dewen, E-mail: dewen-zeng@hotmail.com [College of Chemistry and Chemical Engineering, Central South University, 410083 Changsha (China)

2014-03-15T23:59:59.000Z

304

Transient phenomena in the dielectric breakdown of HfO{sub 2} optical films probed by ultrafast laser pulse pairs  

SciTech Connect (OSTI)

The laser induced breakdown threshold of HfO{sub 2} films is studied with single pairs of pulses of variable delay and 50 fs and 1 ps pulse duration. Two distinct transient regimes are observed that can be related to the relaxation of the electron density from the conduction band via an intermediate state to the valence band. The experimental results are in good agreement with a theoretical model that assumes occupation of mid gap states after the first pulse on a time scale of several tens of picoseconds and subsequent decay of this population via recombination with holes in the valence band on a time scale of several tens of milliseconds.

Nguyen, Duy N.; Emmert, Luke A.; Rudolph, Wolfgang [Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Patel, Dinesh; Menoni, Carmen S. [Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523 (United States)

2010-11-08T23:59:59.000Z

305

Two-Dimensional Polaronic Behavior in the Binary Oxides m-HfO2 and m-ZrO2  

SciTech Connect (OSTI)

We demonstrate that the three-dimensional (3D) binary monoclinic oxides HfO{sub 2} and ZrO{sub 2} exhibit quasi-2D polaron localization and conductivity, which results from a small difference in the coordination of two oxygen sublattices in these materials. The transition between a 2D large polaron into a zero-dimensional small polaron state requires overcoming a small energetic barrier. These results demonstrate how a small asymmetry in the lattice structure can determine the qualitative character of polaron localization and significantly broaden the realm of quasi-2D polaron systems.

McKenna, K. P.; Wolf, M. J.; Shluger, A. L.; Lany, S.; Zunger, A.

2012-03-16T23:59:59.000Z

306

Controlled oxygen vacancy induced p-type conductivity in HfO{sub 2-x} thin films  

SciTech Connect (OSTI)

We have synthesized highly oxygen deficient HfO{sub 2-x} thin films by controlled oxygen engineering using reactive molecular beam epitaxy. Above a threshold value of oxygen vacancies, p-type conductivity sets in with up to 6 times 10{sup 21} charge carriers per cm{sup 3}. At the same time, the band-gap is reduced continuously by more than 1 eV. We suggest an oxygen vacancy induced p-type defect band as origin of the observed behavior.

Hildebrandt, Erwin; Kurian, Jose; Mueller, Mathis M.; Kleebe, Hans-Joachim; Alff, Lambert [Institute of Materials Science, Technische Universitaet Darmstadt, 64287 Darmstadt (Germany); Schroeder, Thomas [IHP, 15236 Frankfurt/Oder (Germany)

2011-09-12T23:59:59.000Z

307

Room temperature strain rate sensitivity in precursor derived HfO{sub 2}/Si-C-N(O) ceramic nanocomposites  

SciTech Connect (OSTI)

Investigation on the room temperature strain rate sensitivity using depth sensing nanoindentation is carried out on precursor derived HfO{sub 2}/Si-C-N(O) ceramic nanocomposite sintered using pulsed electric current sintering. Using constant load method the strain rate sensitivity values are estimated. Lower strain rate sensitivity of ? 3.7 × 10{sup ?3} is observed and the limited strain rate sensitivity of these ceramic nanocomposites is explained in terms of cluster model. It is concluded that presence of amorphous Si-C-N(O) clusters are responsible for the limited flowability in these ceramics.

Sujith, Ravindran; Kumar, Ravi, E-mail: nvrk@iitm.ac.in [Materials Processing Section, Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai-600036, India. (India)] [Materials Processing Section, Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai-600036, India. (India)

2014-01-15T23:59:59.000Z

308

Physical properties and band structure of reactive molecular beam epitaxy grown oxygen engineered HfO{sub 2{+-}x}  

SciTech Connect (OSTI)

We have conducted a detailed thin film growth structure of oxygen engineered monoclinic HfO{sub 2{+-}x} grown by reactive molecular beam epitaxy. The oxidation conditions induce a switching between (111) and (002) texture of hafnium oxide. The band gap of oxygen deficient hafnia decreases with increasing amount of oxygen vacancies by more than 1 eV. For high oxygen vacancy concentrations, defect bands form inside the band gap that induce optical transitions and p-type conductivity. The resistivity changes by several orders of magnitude as a function of oxidation conditions. Oxygen vacancies do not give rise to ferromagnetic behavior.

Hildebrandt, Erwin; Kurian, Jose; Alff, Lambert [Institute of Materials Science, Technische Universitaet Darmstadt, 64287 Darmstadt (Germany)

2012-12-01T23:59:59.000Z

309

Investigations of the g{sub K}-factors in the {sup 175,177,179}Hf Isotopes  

SciTech Connect (OSTI)

In this paper the intrinsic g{sub K} and effective spin g{sub s} factors of the odd-mass {sup 175-179}Hf isotopes have been investigated within the Tamm-Dancoff approximation by using the realistic Saxon-Woods potential. The theoretically calculated g{sub K} and g{sub s}{sup eff} values are compared with experimental data. The comparison of the measured and calculated values of the effective g{sub s} factor shows that the spin polarization explains quite well the observed reduction of g{sub s} from its free-nucleon value.

Yakut, Hakan; Kuliev, Ali [Sakarya University, Department of physics, Sakarya (Turkey); Guliyev, Ekber [National Academy of Sciences, Institute of Physics, Baku (Azerbaijan)

2008-11-11T23:59:59.000Z

310

Energy band alignment of atomic layer deposited HfO{sub 2} on epitaxial (110)Ge grown by molecular beam epitaxy  

SciTech Connect (OSTI)

The band alignment properties of atomic layer HfO{sub 2} film deposited on epitaxial (110)Ge, grown by molecular beam epitaxy, was investigated using x-ray photoelectron spectroscopy. The cross-sectional transmission electron microscopy exhibited a sharp interface between the (110)Ge epilayer and the HfO{sub 2} film. The measured valence band offset value of HfO{sub 2} relative to (110)Ge was 2.28 {+-} 0.05 eV. The extracted conduction band offset value was 2.66 {+-} 0.1 eV using the bandgaps of HfO{sub 2} of 5.61 eV and Ge bandgap of 0.67 eV. These band offset parameters and the interface chemical properties of HfO{sub 2}/(110)Ge system are of tremendous importance for the design of future high hole mobility and low-power Ge-based metal-oxide transistor devices.

Hudait, M. K.; Zhu, Y. [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States); Maurya, D.; Priya, S. [Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States)

2013-03-04T23:59:59.000Z

311

Photo-induced tunneling currents in MOS structures with various HfO{sub 2}/SiO{sub 2} stacking dielectrics  

SciTech Connect (OSTI)

In this study, the current conduction mechanisms of structures with tandem high-k dielectric in illumination are discussed. Samples of Al/SiO{sub 2}/Si (S), Al/HfO{sub 2}/SiO{sub 2}/Si (H), and Al/3HfO{sub 2}/SiO{sub 2}/Si (3H) were examined. The significant observation of electron traps of sample H compares to sample S is found under the double bias capacitance-voltage (C-V) measurements in illumination. Moreover, the photo absorption sensitivity of sample H is higher than S due to the formation of HfO{sub 2} dielectric layer, which leads to larger numbers of carriers crowded through the sweep of V{sub G} before the domination of tunneling current. Additionally, the HfO{sub 2} dielectric layer would block the electrons passing through oxide from valance band, which would result in less electron-hole (e{sup ?}-h{sup +}) pairs recombination effect. Also, it was found that both of the samples S and H show perimeter dependency of positive bias currents due to strong fringing field effect in dark and illumination; while sample 3H shows area dependency of positive bias currents in strong illumination. The non-uniform tunneling current through thin dielectric and through HfO{sub 2} stacking layers are importance to MOS(p) tunneling photo diodes.

Pang, Chin-Sheng; Hwu, Jenn-Gwo, E-mail: jghwu@ntu.edu.tw [Graduate Institute of Electronics Engineering/Department of Electrical Engineering, National Taiwan University, Taipei, 10617, Taiwan (China)] [Graduate Institute of Electronics Engineering/Department of Electrical Engineering, National Taiwan University, Taipei, 10617, Taiwan (China)

2014-04-15T23:59:59.000Z

312

Searches for HCl and HF in comets 103P/Hartley 2 and C/2009 P1 (Garradd) with the Herschel space observatory  

E-Print Network [OSTI]

HCl and HF are expected to be the main reservoirs of fluorine and chlorine wherever hydrogen is predominantly molecular. They are found to be strongly depleted in dense molecular clouds, suggesting freeze-out onto grains in such cold environments. We can then expect that HCl and HF were also the major carriers of Cl and F in the gas and icy phases of the outer solar nebula, and were incorporated into comets. We aimed to measure the HCl and HF abundances in cometary ices as they can provide insights on the halogen chemistry in the early solar nebula. We searched for the J(1-0) lines of HCl and HF at 626 and 1232 GHz, respectively, using the HIFI instrument on board the Herschel Space Observatory. HCl was searched for in comets 103P/Hartley 2 and C/2009 P1 (Garradd), whereas observations of HF were conducted in comet C/2009 P1. In addition, observations of H$_2$O and H$_2^{18}$O lines were performed in C/2009 P1 to measure the H$_2$O production rate. Three lines of CH$_3$OH were serendipitously observed in the ...

Bockelée-Morvan, D; Crovisier, J; Lis, D C; Hartogh, P; Moreno, R; de Val-Borro, M; Blake, G A; Szutowicz, S; Boissier, J; Cernicharo, J; Charnley, S B; Combi, M; Cordiner, M A; de Graauw, T; Encrenaz, P; Kidger, M; Küppers, M; Milam, S N; Müller, H S P; Phillips, T G; Rengel, M

2014-01-01T23:59:59.000Z

313

Sodium fluoride induces apoptosis in mouse embryonic stem cells through ROS-dependent and caspase- and JNK-mediated pathways  

SciTech Connect (OSTI)

Sodium fluoride (NaF) is used as a source of fluoride ions in diverse applications. Fluoride salt is an effective prophylactic for dental caries and is an essential element required for bone health. However, fluoride is known to cause cytotoxicity in a concentration-dependent manner. Further, no information is available on the effects of NaF on mouse embryonic stem cells (mESCs). We investigated the mode of cell death induced by NaF and the mechanisms involved. NaF treatment greater than 1 mM reduced viability and DNA synthesis in mESCs and induced cell cycle arrest in the G{sub 2}/M phase. The addition of NaF induced cell death mainly by apoptosis rather than necrosis. Catalase (CAT) treatment significantly inhibited the NaF-mediated cell death and also suppressed the NaF-mediated increase in phospho-c-Jun N-terminal kinase (p-JNK) levels. Pre-treatment with SP600125 or z-VAD-fmk significantly attenuated the NaF-mediated reduction in cell viability. In contrast, intracellular free calcium chelator, but not of sodium or calcium ion channel blockers, facilitated NaF-induced toxicity in the cells. A JNK specific inhibitor (SP600125) prevented the NaF-induced increase in growth arrest and the DNA damage-inducible protein 45?. Further, NaF-mediated loss of mitochondrial membrane potential was apparently inhibited by pifithrin-? or CAT inhibitor. These findings suggest that NaF affects viability of mESCs in a concentration-dependent manner, where more than 1 mM NaF causes apoptosis through hydroxyl radical-dependent and caspase- and JNK-mediated pathways. -- Highlights: ? The mode of NaF-induced cell death and the mechanisms involved were examined. ? NaF induced mainly apoptotic death of mouse embryonic stem cells (mESCs). ? NaF induced mitochondrial-mediated and caspase-dependent apoptosis. ? JNK- and p53-mediated pathways are involved in NaF-mediated apoptosis in the cells. ? ROS are the up-stream effector in NaF-mediated activation of JNK and p53 in mESCs.

Nguyen Ngoc, Tam Dan [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of)] [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Son, Young-Ok [Graduate Center for Toxicology, School of Medicine, University of Kentucky, Lexington, KY 40536-0305 (United States)] [Graduate Center for Toxicology, School of Medicine, University of Kentucky, Lexington, KY 40536-0305 (United States); Lim, Shin-Saeng [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of) [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Department of Bioactive Material Sciences and Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Shi, Xianglin [Graduate Center for Toxicology, School of Medicine, University of Kentucky, Lexington, KY 40536-0305 (United States)] [Graduate Center for Toxicology, School of Medicine, University of Kentucky, Lexington, KY 40536-0305 (United States); Kim, Jong-Ghee [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of)] [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Heo, Jung Sun [Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of)] [Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Choe, Youngji [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of)] [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Jeon, Young-Mi, E-mail: young@jbnu.ac.kr [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of)] [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Lee, Jeong-Chae, E-mail: leejc88@jbnu.ac.kr [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of) [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Graduate Center for Toxicology, School of Medicine, University of Kentucky, Lexington, KY 40536-0305 (United States); Department of Bioactive Material Sciences and Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

2012-03-15T23:59:59.000Z

314

Process for producing advanced ceramics  

DOE Patents [OSTI]

A process for the synthesis of homogeneous advanced ceramics such as SiC+AlN, SiAlON, SiC+Al.sub.2 O.sub.3, and Si.sub.3 N.sub.4 +AlN from natural clays such as kaolin, halloysite and montmorillonite by an intercalation and heat treatment method. Included are the steps of refining clays, intercalating organic compounds into the layered structure of clays, drying the intercalated mixture, firing the treated atmospheres and grinding the loosely agglomerated structure. Advanced ceramics produced by this procedure have the advantages of homogeneity, cost effectiveness, simplicity of manufacture, ease of grind and a short process time. Advanced ceramics produced by this process can be used for refractory, wear part and structure ceramics.

Kwong, Kyei-Sing (Tuscaloosa, AL)

1996-01-01T23:59:59.000Z

315

Method for producing carbon nanotubes  

DOE Patents [OSTI]

Method for producing carbon nanotubes. Carbon nanotubes were prepared using a low power, atmospheric pressure, microwave-generated plasma torch system. After generating carbon monoxide microwave plasma, a flow of carbon monoxide was directed first through a bed of metal particles/glass beads and then along the outer surface of a ceramic tube located in the plasma. As a flow of argon was introduced into the plasma through the ceramic tube, ropes of entangled carbon nanotubes, attached to the surface of the tube, were produced. Of these, longer ropes formed on the surface portion of the tube located in the center of the plasma. Transmission electron micrographs of individual nanotubes revealed that many were single-walled.

Phillips, Jonathan (Santa Fe, NM); Perry, William L. (Jemez Springs, NM); Chen, Chun-Ku (Albuquerque, NM)

2006-02-14T23:59:59.000Z

316

Method for producing hydrophobic aerogels  

SciTech Connect (OSTI)

A method for treating a dried monolithic aerogel containing non-dispersed particles, with an organometallic surface modifying agent to produce hydrophobic aerogels. The dried, porous hydrophobic aerogels contain a protective layer of alkyl groups, such as methyl groups, on the modified surfaces of the pores of the aerogel. The alkyl groups at the aerogel surface typically contain at least one carbon-metal bond per group.

Hrubesh, Lawrence W. (Pleasanton, CA); Poco, John F. (Livermore, CA); Coronado, Paul R. (Livermore, CA)

1999-01-01T23:59:59.000Z

317

Method for producing hydrophobic aerogels  

SciTech Connect (OSTI)

A method is described for treating a dried monolithic aerogel containing non-dispersed particles, with an organometallic surface modifying agent to produce hydrophobic aerogels. The dried, porous hydrophobic aerogels contain a protective layer of alkyl groups, such as methyl groups, on the modified surfaces of the pores of the aerogel. The alkyl groups at the aerogel surface typically contain at least one carbon-metal bond per group.

Hrubesh, L.W.; Poco, J.F.; Coronado, P.R.

1999-12-21T23:59:59.000Z

318

Electrical characteristics and thermal stability of HfO{sub 2} metal-oxide-semiconductor capacitors fabricated on clean reconstructed GaSb surfaces  

SciTech Connect (OSTI)

HfO{sub 2}/GaSb interfaces fabricated by high-vacuum HfO{sub 2} deposition on clean reconstructed GaSb surfaces were examined to explore a thermally stable GaSb metal-oxide-semiconductor structure with low interface-state density (D{sub it}). Interface Sb-O bonds were electrically and thermally unstable, and post-metallization annealing at temperatures higher than 200?°C was required to stabilize the HfO{sub 2}/GaSb interfaces. However, the annealing led to large D{sub it} in the upper-half band gap. We propose that the decomposition products that are associated with elemental Sb atoms act as interface states, since a clear correlation between the D{sub it} and the Sb coverage on the initial GaSb surfaces was observed.

Miyata, Noriyuki, E-mail: nori.miyata@aist.go.jp; Mori, Takahiro; Yasuda, Tetsuji [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Ohtake, Akihiro [National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044 (Japan); Ichikawa, Masakazu [The University of Tokyo, Tokyo 113-8656 (Japan)

2014-06-09T23:59:59.000Z

319

Effect of nitrogen incorporation on improvement of leakage properties in high-k HfO{sub 2} capacitors treated by N{sub 2}-plasma  

SciTech Connect (OSTI)

The nitrogen incorporation into the HfO{sub 2} films with an EOT (equivalent oxide thickness) of 9 A was performed by N{sub 2}-plasma to improve the electrical properties. The dielectric properties and a leakage current characteristics of the capacitors were investigated as a function of plasma power and plasma treatment temperature. The dielectric constant of the capacitors is not influenced by nitrogen incorporation. The N{sub 2}-plasma treatment at 300 deg. C and 70 W exhibits the most effective influence on improvement of the leakage current characteristics. Leakage current density of the capacitors treated at 300 deg. C and 70 W exhibits a half order of magnitude lower than that without plasma treatment. Nitrogen incorporated into the HfO{sub 2} films possesses the intrinsic effect that drastically reduce the electron leakage current through HfO{sub 2} dielectrics by deactivating the V{sub O} (oxygen vacancy) related gap states.

Seong, Nak-Jin; Yoon, Soon-Gil; Yeom, Seung-Jin; Woo, Hyun-Kyung; Kil, Deok-Sin; Roh, Jae-Sung; Sohn, Hyun-Chul [Department of Materials Science and Engineering, Chungnam National University, Daeduk Science Town, 305-764, Daejon (Korea, Republic of); Hynix Semiconductor Inc., San 136-1 Ami-ri Bubal-eub Icheon-si Kyoungki-do, 467-701 (Korea, Republic of)

2005-09-26T23:59:59.000Z

320

Demonstrating 1 nm-oxide-equivalent-thickness HfO{sub 2}/InSb structure with unpinning Fermi level and low gate leakage current density  

SciTech Connect (OSTI)

In this work, the band alignment, interface, and electrical characteristics of HfO{sub 2}/InSb metal-oxide-semiconductor structure have been investigated. By using x-ray photoelectron spectroscopy analysis, the conduction band offset of 1.78 ± 0.1 eV and valence band offset of 3.35 ± 0.1 eV have been extracted. The transmission electron microscopy analysis has shown that HfO{sub 2} layer would be a good diffusion barrier for InSb. As a result, 1 nm equivalent-oxide-thickness in the 4 nm HfO{sub 2}/InSb structure has been demonstrated with unpinning Fermi level and low leakage current of 10{sup ?4} A/cm{sup ?2}. The D{sub it} value of smaller than 10{sup 12} eV{sup ?1}cm{sup ?2} has been obtained using conduction method.

Trinh, Hai-Dang [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China) [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam); Lin, Yueh-Chin; Nguyen, Hong-Quan; Luc, Quang-Ho [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China)] [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Nguyen, Minh-Thuy; Duong, Quoc-Van; Nguyen, Manh-Nghia [Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam)] [Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam); Wang, Shin-Yuan [Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China)] [Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China); Yi Chang, Edward [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China) [Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu, Taiwan (China); Department of Electronic Engineering, National Chiao Tung University 1001, University Rd., Hsinchu 300, Taiwan (China)

2013-09-30T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Band alignment and interfacial structure of ZnO/Si heterojunction with Al{sub 2}O{sub 3} and HfO{sub 2} as interlayers  

SciTech Connect (OSTI)

Energy band alignment of ZnO/Si heterojunction with thin interlayers Al{sub 2}O{sub 3} and HfO{sub 2} grown by atomic layer deposition has been studied using x-ray photoelectron spectroscopy. The valence band offsets of ZnO/Al{sub 2}O{sub 3} and ZnO/HfO{sub 2} heterojunctions have been determined to be 0.43 and 0.22?eV, respectively. Accordingly, the band alignment ZnO/Si heterojunction is then modified to be 0.34 and 0.50?eV through inserting a thin Al{sub 2}O{sub 3} and HfO{sub 2} layer, respectively. The feasibility to tune the band structure of ZnO/Si heterojunction by selecting a proper interlayer shows great advantage in improving the performance of the ZnO-based optoelectronic devices.

Lu, Hong-Liang, E-mail: honglianglu@fudan.edu.cn; Yang, Ming; Xie, Zhang-Yi; Geng, Yang; Zhang, Yuan; Wang, Peng-Fei; Sun, Qing-Qing; Ding, Shi-Jin; Wei Zhang, David [State Key Laboratory of ASIC and System, Institute of Advanced Nanodevices, School of Microelectronics, Fudan University, Shanghai 200433 (China)

2014-04-21T23:59:59.000Z

322

Thickness-modulated optical dielectric constants and band alignments of HfO{sub x}N{sub y} gate dielectrics  

SciTech Connect (OSTI)

Thickness-modulated optical dielectric constants and band alignments of HfO{sub x}N{sub y} films grown by sputtering have been investigated by spectroscopic ellipsometry (SE) and x-ray photoelectron spectroscopy. Based on SE measurements, it has been noted that an increase in optical dielectric constant and band gap has been observed as a function of the film thickness. Analyses of thickness-dependent band alignment of the HfO{sub x}N{sub y}/Si system indicate that the valence band offset increases, but only slight change in the conduction band offset, resulting from the thickness-induced change in the structure. The suitable optical dielectric constants and band offsets relative to Si make sputtering-derived HfO{sub x}N{sub y} film a promising candidate for high-k gate dielectrics.

He, G.; Zhang, L. D.; Liu, M.; Zhang, J. P.; Wang, X. J. [Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructure, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Zhen, C. M. [Department of Physics, Hebei Advanced Thin Films Laboratory, Hebei Normal University, Shijiazhuang 050016 (China)

2009-01-01T23:59:59.000Z

323

Influence of trimethylaluminum on the growth and properties of HfO{sub 2}/In{sub 0.53}Ga{sub 0.47}As interfaces  

SciTech Connect (OSTI)

The growth and the electrical properties of HfO{sub 2}/In{sub 0.53}Ga{sub 0.47}As interfaces are characterized as a function of exposure to trimethylaluminum (TMA) prior to chemical beam deposition of HfO{sub 2} from an alkoxide precursor. It is shown that TMA can act as a surfactant for HfO{sub 2} growth for (2x4) but not for the group-III-rich (4x2) reconstructed surfaces. The Fermi-level can be unpinned by postdeposition forming gas anneals only for interfaces that were exposed to low doses of TMA at low temperatures. The results are discussed in the context of the interaction between TMA and III-V surfaces.

Hwang, Yoontae; Stemmer, Susanne [Materials Department, University of California, Santa Barbara, California 93106-5050 (United States); Engel-Herbert, Roman [Department of Materials Science and Engineering, Pennsylvania State University, University Park Pennsylvania 16802 (United States)

2011-01-31T23:59:59.000Z

324

The effect of nanocrystallite size in monoclinic HfO{sub 2} films on lattice expansion and near-edge optical absorption  

SciTech Connect (OSTI)

Nanocrystalline monoclinic HfO{sub 2} films were sputter deposited on fused silica substrates, air annealed at 573 to 1273 K to affect crystallite growth, and analyzed by x-ray diffraction and spectrophotometry. Lattice expansion occurs with diminishing crystallite size. O 2p->Hf 5d interband absorption dominates the optical edge at energy E>=6.24 eV, with an optical band gap, E{sub o}=5.48+-0.023, which is independent of crystallite size. However, the strength of a localized resonant band, with onset at 5.65 eV and maximum at 5.94 eV, is affected by crystallite size. Its polaronic origin in a perfect HfO{sub 2} lattice is discussed.

Cisneros-Morales, M. C.; Aita, C. R. [Department of Chemistry and Biochemistry and the Advanced Coatings Experimental Laboratory, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States)

2010-05-10T23:59:59.000Z

325

In situ photoemission spectroscopy study on formation of HfO{sub 2} dielectrics on epitaxial graphene on SiC substrate  

SciTech Connect (OSTI)

High quality HfO{sub 2} dielectrics have been grown on epitaxial graphene on 4H-SiC substrates and have been studied by using in situ x-ray photoemission spectroscopy. The in situ thermal treatment shows that the HfO{sub 2}/graphene/4H-SiC heterojunctions have good thermal stability up to 650 deg. C. A shift of core-level spectra from graphene layer implies that charge transfer takes place at the interface. The high thermal stability and sufficient barrier heights between HfO{sub 2} and graphene indicate that high-k dielectric grown on graphene is very promising for the development of graphene-based electronic devices.

Chen, Q.; Huang, H.; Chen, W.; Wee, A. T. S.; Feng, Y. P. [Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Chai, J. W.; Zhang, Z.; Pan, J. S.; Wang, S. J. [Institute of Materials Research and Engineering, A-STAR (Agency for Science, Technology, and Research), 3 Research Link, Singapore 117602 (Singapore)

2010-02-15T23:59:59.000Z

326

Electron-stimulated desorption from polished and vacuum fired 316LN stainless steel coated with Ti-Zr-Hf-V  

SciTech Connect (OSTI)

In this study, two identical 316LN stainless steel tubular samples, which had previously been polished and vacuum-fired and then used for the electron-stimulated desorption (ESD) experiments, were coated with Ti-Zr-Hf-V with different morphologies: columnar and dense. ESD measurement results after nonevaporable getter (NEG) activation to 150, 180, 250, and 350?°C indicated that the values for the ESD yields are significantly (2–20 times) lower than the data from our previous study with similar coatings on nonvacuum-fired samples. Based on these results, the lowest pressure and best long-term performance in particle accelerators will be achieved with a vacuum-fired vacuum chamber coated with dense Ti-Zr-Hf-V coating activated at 180?°C. This is likely due to the following facts: after NEG activation, the hydrogen concentration inside the NEG was lower than in the bulk stainless steel substrate; the NEG coating created a barrier for gas diffusion from the sample bulk to vacuum; the dense NEG coating performed better as a barrier than the columnar NEG coating.

Malyshev, Oleg B., E-mail: oleg.malyshev@stfc.ac.uk; Valizadeh, Reza; Hogan, Benjamin T.; Hannah, Adrian N. [ASTeC, STFC Daresbury Laboratory, Daresbury, Warrington, WA4 4AD Cheshire (United Kingdom)

2014-11-01T23:59:59.000Z

327

Producing biofuels using polyketide synthases  

DOE Patents [OSTI]

The present invention provides for a non-naturally occurring polyketide synthase (PKS) capable of synthesizing a carboxylic acid or a lactone, and a composition such that a carboxylic acid or lactone is included. The carboxylic acid or lactone, or derivative thereof, is useful as a biofuel. The present invention also provides for a recombinant nucleic acid or vector that encodes such a PKS, and host cells which also have such a recombinant nucleic acid or vector. The present invention also provides for a method of producing such carboxylic acids or lactones using such a PKS.

Katz, Leonard; Fortman, Jeffrey L; Keasling, Jay D

2013-04-16T23:59:59.000Z

328

Fatty acid-producing hosts  

DOE Patents [OSTI]

Described are hosts for overproducing a fatty acid product such as a fatty acid. The hosts include an exogenous nucleic acid encoding a thioesterase and, optionally, an exogenous nucleic acid encoding an acetyl-CoA carboxylase, wherein an acyl-CoA synthetase in the hosts are functionally delected. The hosts prefereably include the nucleic acid encoding the thioesterase at an intermediate copy number. The hosts are preferably recominantly stable and growth-competent at 37.degree. C. Methods of producing a fatty acid product comprising culturing such hosts at 37.degree. C. are also described.

Pfleger, Brian F; Lennen, Rebecca M

2013-12-31T23:59:59.000Z

329

Local structure around Er{sup 3+} in SiO{sub 2}-HfO{sub 2} glassy waveguides using EXAFS  

SciTech Connect (OSTI)

Er{sup 3+}-doped SiO{sub 2}-HfO{sub 2} glassy waveguides with HfO{sub 2} concentrations ranging from 10 to 50 mol % were prepared using the sol-gel route and deposited on v-SiO{sub 2} substrates using the dip-coating technique. The local environment around Er{sup 3+} ions was determined from Er L{sub 3}-edge extended x-ray-absorption fine-structure (EXAFS) measurements. The first coordination shell around Er{sup 3+} ions is composed of oxygen atoms. Hafnium is the main constituent of the second coordination shell of Er{sup 3+}, differing from the cases of pure SiO{sub 2} and SiO{sub 2}-TiO{sub 2} glassy hosts, in which silicon is the main atomic species. The local structure around Er{sup 3+} ions has been found to be independent on HfO{sub 2} concentration within the studied composition range. This fact implies that Er{sup 3+} ions are preferentially dispersed in HfO{sub 2}-rich regions of the glassy waveguide, even at the lowest HfO{sub 2} concentration. For all samples, no Er{sup 3+}-Er{sup 3+} coordination shell has been detected by EXAFS. The presented structural results allow us to understand some spectroscopic properties typical of Er{sup 3+}-doped SiO{sub 2} glassy waveguides co-doped with HfO{sub 2}.

Afify, N. D.; Dalba, G.; Armellini, C.; Ferrari, M.; Rocca, F.; Kuzmin, A. [Dipartimento di Fisica, Universita degli Studi di Trento, Via Sommarive 14, I-38100 Povo (Trento) (Italy); IFN-CNR, Istituto di Fotonica e Nanotecnologie del Consiglio Nazionale delle Ricerche, Sezione FBK-CeFSA di Trento, Via alla Cascata 56/C, I-38100 Povo (Trento) (Italy); Institute of Solid State Physics, University of Latvia, LV-1063 RIGA (Latvia)

2007-07-01T23:59:59.000Z

330

Measurement of the melting point temperature of several lithium-sodium-beryllium fluoride salt (FLINABE) mixtures.  

SciTech Connect (OSTI)

The molten salt Flibe, a combination of lithium and beryllium flourides, was studied for molten salt fission reactors and has been proposed as a breeder and coolant for the fusion applications. 2LiF-BeF{sub 2} melts at 460 C. LiF-BeF{sub 2} melts at a lower temperature, 363 C, but is rather viscous and has less lithium breeder. In the Advanced Power Extraction (APEX) Program, concepts with a free flowing ternary molten salt for the first wall surface and blanket were investigated. The molten salt (FLiNaBe, a ternary mixture of LiF, BeF2 and NaF) salt was selected because a melting temperature below 350 C that would provide an attractive operating temperature window for a reactor application appeared possible. This information came from a Russian binary phase diagram and a US ternary phase diagram in the 1960's that were not wholly consistent. To confirm that a ternary salt with a low melting temperature existed, several combinations of the fluoride salts, LiF, NaF and, BeF{sub 2}, were melted in a small stainless steel crucible under vacuum. The proportions of the three salts were selected to yield conglomerate salts with as low a melting temperature as possible. The temperature of the salts and the crucible were recorded during the melting and subsequent re-solidification using a thermocouple directly in the salt pool and two thermocouples embedded in the crucible. One mixture had an apparent melting temperature of 305 C. Particular attention was paid to the cooling curve of the salt temperature to observe evidence of any mixed intermediate phases between the fully liquid and fully solid states. The clarity, texture, and thickness were observed and noted as well. The test system, preparation of the mixtures, and the melting procedure are described. The temperature curves for the melting and cooling of each of the mixtures are presented along with the apparent melting points. Thermal modeling of the salt pool and crucible was also done and is reported in a separate paper.

Boyle, Timothy J.; Troncosa, Kenneth P.; Nygren, Richard Einar; Lutz, Thomas Joseph; McDonald, Jimmie M.; Tanaka, Tina Joan; Ulrickson, Michael Andrew

2004-09-01T23:59:59.000Z

331

Vortex Diode Analysis and Testing for Fluoride Salt-Cooled High-Temperature Reactors  

SciTech Connect (OSTI)

Fluidic diodes are presently being considered for use in several fluoride salt-cooled high-temperature reactor designs. A fluidic diode is a passive device that acts as a leaky check valve. These devices are installed in emergency heat removal systems that are designed to passively remove reactor decay heat using natural circulation. The direct reactor auxiliary cooling system (DRACS) uses DRACS salt-to-salt heat exchangers (DHXs) that operate in a path parallel to the core flow. Because of this geometry, under normal operating conditions some flow bypasses the core and flows through the DHX. A flow diode, operating in reverse direction, is-used to minimize this flow when the primary coolant pumps are in operation, while allowing forward flow through the DHX under natural circulation conditions. The DRACSs reject the core decay heat to the environment under loss-of-flow accident conditions and as such are a reactor safety feature. Fluidic diodes have not previously been used in an operating reactor system, and therefore their characteristics must be quantified to ensure successful operation. This report parametrically examines multiple design parameters of a vortex-type fluidic diode to determine the size of diode needed to reject a particular amount of decay heat. Additional calculations were performed to size a scaled diode that could be tested in the Oak Ridge National Laboratory Liquid Salt Flow Loop. These parametric studies have shown that a 152.4 mm diode could be used as a test article in that facility. A design for this diode is developed, and changes to the loop that will be necessary to test the diode are discussed. Initial testing of a scaled flow diode has been carried out in a water loop. The 150 mm diode design discussed above was modified to improve performance, and the final design tested was a 171.45 mm diameter vortex diode. The results of this testing indicate that diodicities of about 20 can be obtained for diodes of this size. Experimental results show similar trends as the computational fluid dynamics (CFD) results presented in this report; however, some differences exist that will need to be assessed in future studies. The results of this testing will be used to improve the diode design to be tested in the liquid salt loop system.

Yoder Jr, Graydon L [ORNL; Elkassabgi, Yousri M. [Texas A& M University, Kingsville; De Leon, Gerardo I. [Texas A& M University, Kingsville; Fetterly, Caitlin N. [Texas A& M University, Kingsville; Ramos, Jorge A. [Texas A& M University, Kingsville; Cunningham, Richard Burns [University of Tennessee, Knoxville (UTK)

2012-02-01T23:59:59.000Z

332

First principle study of elastic and thermodynamic properties of ZrZn{sub 2} and HfZn{sub 2} under high pressure  

SciTech Connect (OSTI)

A comprehensive investigation of the structural, elastic, and thermodynamic properties for Laves-phases ZrZn{sub 2} and HfZn{sub 2} are conducted using density functional total energy calculations combined with the quasi-harmonic Debye model. The optimized lattice parameters of ZrZn{sub 2} and HfZn{sub 2} compare well with available experimental values. We estimated the mechanical behaviors of both compounds under compression, including mechanical stability, Young's modulus, Poisson's ratio, ductility, and anisotropy. Additionally, the thermodynamic properties as a function of pressure and temperature are analyzed and found to be in good agreement with the corresponding experimental data.

Sun, Na; Zhang, Xinyu, E-mail: jiaqianqin@gmail.com; Ning, Jinliang; Zhang, Suhong; Liang, Shunxing; Ma, Mingzhen; Liu, Riping [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Qin, Jiaqian, E-mail: jiaqianqin@gmail.com [Metallurgy and Materials Science Research Institute, Chulalongkorn University, Bangkok 10330 (Thailand)

2014-02-28T23:59:59.000Z

333

Characterization of uraninite nanoparticles produced by Shewanella...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

uraninite nanoparticles produced by Shewanella oneidensis MR-1 . Characterization of uraninite nanoparticles produced by Shewanella oneidensis MR-1 . Abstract: The reduction of...

334

Effects of fluorine incorporation into HfO{sub 2} gate dielectrics on InP and In{sub 0.53}Ga{sub 0.47}As metal-oxide-semiconductor field-effect-transistors  

SciTech Connect (OSTI)

In this work, the effects of fluorine (F) incorporation on electrical characteristics of HfO{sub 2}/InP and HfO{sub 2}/In{sub 0.53}Ga{sub 0.47}As gate stack are presented. F had been introduced into HfO{sub 2} gate dielectric by postgate CF{sub 4} plasma treatment, which was confirmed by x-ray photoelectron spectroscopy analysis and a secondary ion mass spectrometry technique. Compared to the control sample, fluorinated samples had great improvements in subthreshold swing, hysteresis, the normalized extrinsic transconductance, and the normalized drain current. These improvements can be attributed to the reduction in fixed charge in the HfO{sub 2} bulk and less interface trap density at the HfO{sub 2}/III-V interface.

Chen Yenting; Zhao Han; Wang Yanzhen; Xue Fei; Zhou Fei; Lee, Jack C. [Department of Electrical and Computer Engineering, Microelectronics Research Center, University of Texas at Austin, Texas 78758 (United States)

2010-06-21T23:59:59.000Z

335

Perfluorooctane Sulfonyl Fluoride as an Initiator in Hot-Filament Chemical Vapor Deposition of Fluorocarbon  

E-Print Network [OSTI]

of Fluorocarbon Thin Films Hilton G. Pryce Lewis, Jeffrey A. Caulfield, and Karen K. Gleason*, Department pathways available via HFCVD makes it possible to produce polymeric fluorocarbon films spectroscopically

Gleason, Karen K.

336

Does fluoride disrupt hydrogen bond network in cationic lipid bilayer? Time-dependent fluorescence shift of Laurdan and molecular dynamics simulations  

SciTech Connect (OSTI)

Time-dependent fluorescence shift (TDFS) of Laurdan embedded in phospholipid bilayers reports on hydration and mobility of the phospholipid acylgroups. Exchange of H{sub 2}O with D{sub 2}O prolongs the lifetime of lipid-water and lipid-water-lipid interactions, which is reflected in a significantly slower TDFS kinetics. Combining TDFS measurements in H{sub 2}O and D{sub 2}O hydrated bilayers with atomistic molecular dynamics (MD) simulations provides a unique tool for characterization of the hydrogen bonding at the acylgroup level of lipid bilayers. In this work, we use this approach to study the influence of fluoride anions on the properties of cationic bilayers composed of trimethylammonium-propane (DOTAP). The results obtained for DOTAP are confronted with those for neutral phosphatidylcholine (DOPC) bilayers. Both in DOTAP and DOPC H{sub 2}O/D{sub 2}O exchange prolongs hydrogen-bonding lifetime and does not disturb bilayer structure. These results are confirmed by MD simulations. TDFS experiments show, however, that for DOTAP this effect is cancelled in the presence of fluoride ions. We interpret these results as evidence that strongly hydrated fluoride is able to steal water molecules that bridge lipid carbonyls. Consequently, when attracted to DOTAP bilayer, fluoride disrupts the local hydrogen-bonding network, and the differences in TDFS kinetics between H{sub 2}O and D{sub 2}O hydrated bilayers are no longer observed. A distinct behavior of fluoride is also evidenced by MD simulations, which show different lipid-ion binding for Cl{sup ?} and F{sup ?}.

Pokorna, Sarka; Jurkiewicz, Piotr; Hof, Martin, E-mail: martin.hof@jh-inst.cas.cz [J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic v.v.i., Dolejskova 3, 18223 Prague 8 (Czech Republic); Vazdar, Mario [Division of Organic Chemistry and Biochemistry, Rudjer Boškovi? Institute, P.O.B. 180, HR-10002 Zagreb (Croatia); Cwiklik, Lukasz [J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic v.v.i., Dolejskova 3, 18223 Prague 8 (Czech Republic); Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6 (Czech Republic); Jungwirth, Pavel [Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6 (Czech Republic); Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland)

2014-12-14T23:59:59.000Z

337

Deposition of TiN and HfO{sub 2} in a commercial 200 mm remote plasma atomic layer deposition reactor  

SciTech Connect (OSTI)

The authors describe a remote plasma atomic layer deposition reactor (Oxford Instruments FlexAL trade mark sign ) that includes an inductively coupled plasma source and a load lock capable of handling substrates up to 200 mm in diameter. The deposition of titanium nitride (TiN) and hafnium oxide (HfO{sub 2}) is described for the combination of the metal-halide precursor TiCl{sub 4} and H{sub 2}-N{sub 2} plasma and the combination of the metallorganic precursor Hf[N(CH{sub 3})(C{sub 2}H{sub 5})]{sub 4} and O{sub 2} plasma, respectively. The influence of the plasma exposure time and substrate temperature has been studied and compositional, structural, and electrical properties are reported. TiN films with a low Cl impurity content were obtained at 350 deg. C at a growth rate of 0.35 A /cycle with an electrical resistivity as low as 150 {mu}{omega} cm. Carbon-free (detection limit <2 at. %) HfO{sub 2} films were obtained at a growth rate of 1.0 A /cycle at 290 deg. C. The thickness and resisitivity nonuniformity was <5% for the TiN and the thickness uniformality was <2% for the HfO{sub 2} films as determined over 200 mm wafers.

Heil, S. B. S.; Hemmen, J. L. van; Hodson, C. J.; Singh, N.; Klootwijk, J. H.; Roozeboom, F.; Sanden, M. C. M. van de; Kessels, W. M. M. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Oxford Instruments Plasma Technology, North End, Yatton BS49 4AP (United Kingdom); Philips Research Laboratories, High Tech Campus 4, 5656 AE Eindhoven (Netherlands); NXP Semiconductors Research, High Tech Campus 4, 5656 AE Eindhoven (Netherlands); Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2007-09-15T23:59:59.000Z

338

Atomic layer deposition of Hf{sub x}Al{sub y}C{sub z} as a work function material in metal gate MOS devices  

SciTech Connect (OSTI)

As advanced silicon semiconductor devices are transitioning from planar to 3D structures, new materials and processes are needed to control the device characteristics. Atomic layer deposition (ALD) of Hf{sub x}Al{sub y}C{sub z} films using hafnium chloride and trimethylaluminum precursors was combined with postdeposition anneals and ALD liners to control the device characteristics in high-k metal-gate devices. Combinatorial process methods and technologies were employed for rapid electrical and materials characterization of various materials stacks. The effective work function in metal–oxide–semiconductor capacitor devices with the Hf{sub x}Al{sub y}C{sub z} layer coupled with an ALD HfO{sub 2} dielectric was quantified to be mid-gap at ?4.6?eV. Thus, Hf{sub x}Al{sub y}C{sub z} is a promising metal gate work function material that allows for the tuning of device threshold voltages (V{sub th}) for anticipated multi-V{sub th} integrated circuit devices.

Lee, Albert, E-mail: alee@intermolecular.com; Fuchigami, Nobi; Pisharoty, Divya; Hong, Zhendong; Haywood, Ed; Joshi, Amol; Mujumdar, Salil; Bodke, Ashish; Karlsson, Olov [Intermolecular, 3011 North First Street, San Jose, California 95134 (United States); Kim, Hoon; Choi, Kisik [GLOBALFOUNDRIES Technology Research Group, 257 Fuller Road, Albany, New York 12309 (United States); Besser, Paul [GLOBALFOUNDRIES, 1050 East Arques, Sunnyvale, California 94085 (United States)

2014-01-15T23:59:59.000Z

339

Ion-radical synergy in HfO{sub 2} etching studied with a XeF{sub 2}/Ar{sup +} beam setup  

SciTech Connect (OSTI)

To gain more insight into fundamental aspects of the etching behavior of Hf-based high-k materials in plasma etch reactors, HfO{sub 2} films were etched in a multiple-beam setup consisting of a low energy Ar{sup +} ion beam and a XeF{sub 2} radical beam. The etch rate and etch products were monitored by real-time ellipsometry and mass spectrometry, respectively. Although etching of HfO{sub 2} in XeF{sub 2}/Ar{sup +} chemistry is mainly a physical effect, an unambiguous proof of the ion-radical synergistic effect for the etching of HfO{sub 2} is presented. The etch yield for 400 eV Ar{sup +} ions at a substrate temperature of 300 deg. C was 0.3 atoms/ion for Ar{sup +} sputtering and increased to 2 atoms/ion when XeF{sub 2} was also supplied. The etch yield proved to follow the common square root of ion energy dependence both for pure sputtering and radical enhanced etching, with a threshold energy at room temperature of 69{+-}17 eV for Ar{sup +} ions and 54{+-}14 eV for Ar{sup +} ions with XeF{sub 2}.

Gevers, P. M.; Beijerinck, H. C. W.; Sanden, M. C. M. van de; Kessels, W. M. M. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2008-04-15T23:59:59.000Z

340

Band offsets of Al{sub 2}O{sub 3} and HfO{sub 2} oxides deposited by atomic layer deposition technique on hydrogenated diamond  

SciTech Connect (OSTI)

High-k oxide insulators (Al{sub 2}O{sub 3} and HfO{sub 2}) have been deposited on a single crystalline hydrogenated diamond (H-diamond) epilayer by an atomic layer deposition technique at temperature as low as 120 Degree-Sign C. Interfacial electronic band structures are characterized by X-ray photoelectron spectroscopy. Based on core-level binding energies and valence band maximum values, valence band offsets are found to be 2.9 {+-} 0.2 and 2.6 {+-} 0.2 eV for Al{sub 2}O{sub 3}/H-diamond and HfO{sub 2}/H-diamond heterojunctions, respectively. Band gaps of the Al{sub 2}O{sub 3} and HfO{sub 2} have been determined to be 7.2 {+-} 0.2 and 5.4 {+-} 0.2 eV by measuring O 1s energy loss spectra, respectively. Both the Al{sub 2}O{sub 3}/H-diamond and HfO{sub 2}/H-diamond heterojunctions are concluded to be type-II staggered band configurations with conduction band offsets of 1.2 {+-} 0.2 and 2.7 {+-} 0.2 eV, respectively.

Liu, J. W.; Liao, M. Y.; Imura, M. [Optical and Electronic Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Koide, Y. [Optical and Electronic Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Center of Materials Research for Low Carbon Emission, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

2012-12-17T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Addendum to ''Phase selection and transition in Hf-rich hafnia-titania nanolaminates'' (on SiO{sub 2}) [J. Appl. Phys. 109, 123523 (2011)]: Hafnon formation  

SciTech Connect (OSTI)

Continued investigation of hafnia-titania nanolaminates on silica substrates after long term annealing shows that hafnon (HfSiO{sub 4}) is formed, in addition to the previously reported phases. Here, a 293 nm-thick stack of 5 nm HfO{sub 2}-4 nm TiO{sub 2} bilayers (0.51 mole fraction HfO{sub 2}) is sputter deposited on fused SiO{sub 2} and annealed in air at 1173 K for up to 192 h and then at 1273 K for up to 96 h. X-ray diffraction shows that hafnon crystallizes after 24 h at 1273 K. Micro-Raman spectroscopy/microscopy shows that hafnon crystallization is heterogeneous. No film-substrate reaction is observed for single layer HfO{sub 2} on SiO{sub 2} annealed under similar conditions. We suggest the nanolaminate's complex annealed microstructure provides fast diffusion paths that enable hafnon formation.

Cisneros-Morales, Massiel Cristina; Aita, Carolyn Rubin [Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States)

2012-05-15T23:59:59.000Z

342

Microstructural Characterization and Shape Memory Response of Ni-Rich NiTiHf and NiTiZr High Temperature Shape Memory Alloys  

E-Print Network [OSTI]

NiTiHf and NiTiZr high temperature shape memory alloys (HTSMAs) have drawn a great deal of attention as cheaper alternatives to Pt, Pd and Au alloyed NiTi-based HTSMAs while NiTiZr alloys also providing at least 20% weight reduction then its Ni...

Evirgen, Alper

2014-08-14T23:59:59.000Z

343

Quantum dynamics of molecular multiphoton excitation in intense laser and static electric fields: Floquet theory, quasienergy spectra, and application to the HF molecule  

E-Print Network [OSTI]

of the HF molecule as functions of field strengths and frequency. Nonlinear effects such as power broadening, dynamic Stark shift, Autler–Townes multiplet splitting, hole burning, and S?hump behaviors, etc., are observed and discussed in terms of quasienergy...

Chu, Shih-I; Tietz, James V.; Datta, Krishna K.

1982-01-01T23:59:59.000Z

344

ULF wave occurrence statistics in a high-latitude HF Doppler sounder D. M. Wright, T. K. Yeoman, T. B. Jones  

E-Print Network [OSTI]

ULF wave occurrence statistics in a high-latitude HF Doppler sounder D. M. Wright, T. K. Yeoman, T was to establish the optimum con®guration for a new high-latitude Doppler sounder experiment, called DOPE (Wright, 1996; Wright et al., 1997), and to determine the likelihood of the experiment observing pulsation eects

Paris-Sud XI, Université de

345

In situ study of HfO{sub 2} atomic layer deposition on InP(100)  

SciTech Connect (OSTI)

The interfacial chemistry of the native oxide and chemically treated InP samples during atomic layer deposition (ALD) HfO{sub 2} growth at 250 Degree-Sign C has been studied by in situ X-ray photoelectron spectroscopy. The In-oxide concentration is seen to gradually decrease on the native oxide and acid etched samples. No significant changes of the P-oxide concentrations are detected, while the P-oxides chemical states are seen to change gradually during the initial cycles of ALD on the native oxide and the chemically treated samples. (NH{sub 4}){sub 2}S treatment strongly decreases In-oxide and P-oxide concentrations prior to ALD and maintains low concentrations during the ALD process.

Dong, H.; Brennan, B.; Kim, J.; Hinkle, C. L.; Wallace, R. M. [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States)] [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States); Zhernokletov, D. [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States)] [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States)

2013-04-29T23:59:59.000Z

346

Interfacial Layer Growth Condition Dependent Carrier Transport Mechanisms in HfO2/SiO2 Gate Stacks  

SciTech Connect (OSTI)

The temperature and field dependent leakage current in HfO{sub 2}/SiO{sub 2} gate stack for in situ steam grown and chemical interfacial layers (ILs) are studied in the temperature range of 20 C to 105 C. Poole-Frenkel mechanism in high field whereas Ohmic conduction in low field region are dominant for both devices. Leakage current decreases whereas both trap energy level ({phi}{sub t}) and activation energy (E{sub a}) increase for chemically grown IL devices. The trap level energy, ({phi}{sub t}) -0.2 eV, indicates that doubly charged oxygen vacancies (V{sup 2-}) are the active electron traps which contribute to the leakage current in these gate stacks.

Sahoo, S. K.; Misra, D.

2012-06-04T23:59:59.000Z

347

Optical properties of chromium and neodymium in zirconium-barium-lanthanum-aluminum fluoride glass. Final report, October 1987-September 1988  

SciTech Connect (OSTI)

The optical properties are reported of chromium and neodymium doped in zirconium-barium-lanthanum-aluminum fluoride glass (ZBLA). The fluorescence of Cr(3+) and of co-doped Cr(3+), Nd(3+) glasses is investigated. Fluorescence decay rates of Cr(3+) and Nd(3+) are measured at various temperatures, and the excitation transfer efficiency between Cr(3+) and Nd(3+) is determined. The absorption spectrum of Nd(3+):ZBLA is characterized in terms of the Judd-Ofelt model of crystal field-induced electric-dipole transitions. The three phenomenological intensity parameters for Nd(3+) in ZBLA glass Omega sub 2,4,6, are compared to those obtained for Nd(3+) in Y3Al5Ol2, Gd3S2Al3Ol2, and LHG-8 glass.

Hanson, F.E.; Caspers, H.H.

1993-08-01T23:59:59.000Z

348

ELECTRONIC SOLUTION SPECTRA FOR URANIUM AND NEPTUNIUM IN OXIDATION STATES (III) TO (VI) IN ANHYDROUS HYDROGEN FLUORIDE  

SciTech Connect (OSTI)

Spectra have been recorded for solutions in anhydrous hydrogen fluoride (AHF) of uranium and neptunium in oxidation states (III) to (VI). The spectra for U(III), Np(III) and Np(IV) in AHF are very similar to those in acidified aqueous solution, but that for U(IV) suggests that the cationic species is UF{sub 2}{sup 2+}. The AHF spectra for the elements in oxidation states (V) and (VI) are not comparable with those of the formally analogous aqueous solutions, where the elements exist as well-defined dioxo-cations. However, the AHF spectra can be related to spectra in the gas phase, in the solid state or in non-aqueous solvents for each element in its appropriate oxidation state.

Baluka, M.; Edelstein, N.; O'Donnell, T. A.

1980-10-01T23:59:59.000Z

349

Mechanisms for fluoride-promoted dissolution of bayerite [{beta}-Al(OH){sub 3}(s)] and boehmite [{gamma}-AlOOH]: {sup 19}F-NMR spectroscopy and aqueous surface chemistry  

SciTech Connect (OSTI)

Some reactions that control the dissolution of bayerite [{beta}-Al(OH){sub 3}(s)] and boehmite [{gamma}-AlOOH] were identified by comparing the adsorption chemistry, the dissolution rates, and solid-state {sup 19}F-NMR spectra of the reacting surfaces. The {sup 19}F-NMR spectra of bayerite distinguish two sites for fluoride reaction that vary in relative concentration with the total adsorbate density. One resonance at {minus}131 ppm is assigned to fluoride bridges and the other resonance at {minus}142 ppm is assigned to fluoride at terminal sites. These same resonances are observed on boehmite, in addition to a third resonance at {minus}151 ppm that is tentatively assigned to aqueous AlF{sub n}(H{sub 2}O){sub 6{minus}n}{sup (3{minus}n)+} (aq) complexes in pores. Peak broadening due to dipolar coupling between surface fluorides at high loading indicates that these sites are in close proximity. A consistent picture of dissolution is derived by considering the {sup 19}F-NMR results, the aqueous experiments, and information derived from the studies of aqueous complexes, particularly studies of the dissociation mechanisms of aqueous multimers. Both fluoride and adsorbed proton enhance the dissolution rates via a series of pathways that may be coupled to one another, and there is a profound dependence of the rate on the concentration of adsorbed protons and adsorbed fluorides. Particularly important are fluoride-substituted bridges and sites where aluminum atoms are bonded to several terminal fluorides or hydroxyls. These results illustrate that it is possible to test hypotheses about molecular-scale processes if adsorption studies are coupled to spectroscopy and ligand-promoted dissolution experiments where reaction via different pathways can be distinguished.

Nordin, J.P.; Sullivan, D.J.; Phillips, B.L.; Casey, W.H.

1999-11-01T23:59:59.000Z

350

Biomass Producer or Collector Tax Credit (Oregon)  

Broader source: Energy.gov [DOE]

 The Oregon Department of Energy provides a tax credit for agricultural producers or collectors of biomass.  The credit can be used for eligible biomass used to produce biofuel; biomass used in...

351

Quantifying the parameters of successful agricultural producers  

E-Print Network [OSTI]

The primary purpose of the study was to quantify the parameters of successful agricultural producers. Through the use of the Financial and Risk Management (FARM) Assistance database, this study evaluated economic measures for row-crop producers...

Kaase, Gregory Herman

2006-08-16T23:59:59.000Z

352

In situ observation of oxygen gettering by titanium overlayer on HfO{sub 2}/SiO{sub 2}/Si using high-resolution Rutherford backscattering spectroscopy  

SciTech Connect (OSTI)

Oxygen gettering by Ti overlayer (2-8 nm) on a HfO{sub 2}(3 nm)/SiO{sub 2}(1.5 nm)/Si(001) structure was investigated using high-resolution Rutherford backscattering spectroscopy. After deposition of a thin Ti layer, the interfacial SiO{sub 2} layer is reduced by {approx}0.2 nm and the released oxygen is incorporated in Ti layer. Subsequent annealing at 330 deg. C in UHV causes further reduction by 0.1-0.8 nm depending on the Ti layer thickness. In addition to the reduction of the SiO{sub 2} layer, significant oxygen depletion in the HfO{sub 2} layer was observed for thicker Ti layers after annealing.

Nakajima, Kaoru; Fujiyoshi, Akira; Ming, Zhao; Suzuki, Motofumi; Kimura, Kenji [Department of Micro Engineering, Kyoto University, Yoshida-Honmachi, Sakyo, Kyoto 606-8501 (Japan)

2007-09-15T23:59:59.000Z

353

Intermixing between HfO{sub 2} and GeO{sub 2} films deposited on Ge(001) and Si(001): Role of the substrate  

SciTech Connect (OSTI)

Thermally driven atomic transport in HfO{sub 2}/GeO{sub 2}/substrate structures on Ge(001) and Si(001) was investigated in N{sub 2} ambient as function of annealing temperature and time. As-deposited stacks showed no detectable intermixing and no instabilities were observed on Si. On Ge, loss of O and Ge was detected in all annealed samples, presumably due to evolution of GeO from the GeO{sub 2}/Ge interface. In addition, hafnium germanate is formed at 600 deg. C. Our data indicate that at 500 deg. C and above HfO{sub 2}/GeO{sub 2} stacks are stable only if isolated from the Ge substrate.

Soares, G. V.; Krug, C. [Instituto de Fisica, UFRGS, Porto Alegre, Rio Grande do Sul 91509-900 (Brazil); Miotti, L.; Bastos, K. P.; Lucovsky, G. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States); Baumvol, I. J. R. [Instituto de Fisica, UFRGS, Porto Alegre, Rio Grande do Sul 91509-900 (Brazil); Universidade de Caxias do Sul, Caxias do Sul, Rio Grande do Sul 95070-560 (Brazil); Radtke, C. [Instituto de Quimica, UFRGS, Porto Alegre, Rio Grande do Sul 91509-900 (Brazil)

2011-03-28T23:59:59.000Z

354

Highly transparent low capacitance plasma enhanced atomic layer deposition Al{sub 2}O{sub 3}-HfO{sub 2} tunnel junction engineering  

SciTech Connect (OSTI)

The development of metallic single electron transistor (SET) depends on the downscaling and the electrical properties of its tunnel junctions. These tunnel junctions should insure high tunnel current levels, low thermionic current, and low capacitance. The authors use atomic layer deposition to fabricate Al{sub 2}O{sub 3} and HfO{sub 2} thin layers. Tunnel barrier engineering allows the achievement of low capacitance Al{sub 2}O{sub 3} and HfO{sub 2} tunnel junctions using optimized annealing and plasma exposure conditions. Different stacks were designed and fabricated to increase the transparency of the tunnel junction while minimizing thermionic current. This tunnel junction is meant to be integrated in SET to enhance its electrical properties (e.g., operating temperature, I{sub ON}/I{sub OFF} ratio)

El Hajjam, Khalil, E-mail: khalil.el-hajjam@insa-lyon.fr [INL, INSA, UMR CNRS 5270, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex, France and Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec (Canada); Baboux, Nicolas; Calmon, Francis [INL, INSA, UMR CNRS 5270, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Souifi, Abdelkader [Laboratoire Nanotechnologies Nanosystèmes (LN2)-CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec (Canada); Poncelet, Olivier; Francis, Laurent A. [ICTEAM, ELEN, UCL, Place du Levant 3, 1348 Louvain-la-Neuve (Belgium); Ecoffey, Serge; Drouin, Dominique [Laboratoire Nanotechnologies Nanosystèmes (LN2)-CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec, Canada and Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec (Canada)

2014-01-15T23:59:59.000Z

355

In Situ Synchrotron Based X-ray Fluorescence and Scattering Measurements During Atomic Layer Deposition: Initial Growth of HfO2 on Si and Ge Substrates  

SciTech Connect (OSTI)

The initial growth of HfO{sub 2} was studied by means of synchrotron based in situ x-ray fluorescence (XRF) and grazing incidence small angle x-ray scattering (GISAXS). HfO{sub 2} was deposited by atomic layer deposition (ALD) using tetrakis(ethylmethylamino)hafnium and H{sub 2}O on both oxidized and H-terminated Si and Ge surfaces. XRF quantifies the amount of deposited material during each ALD cycle and shows an inhibition period on H-terminated substrates. No inhibition period is observed on oxidized substrates. The evolution of film roughness was monitored using GISAXS. A correlation is found between the inhibition period and the onset of surface roughness.

K Devloo-Casier; J Dendooven; K Ludwig; G Lekens; J DHaen; C Detavernier

2011-12-31T23:59:59.000Z

356

In situ study of the role of substrate temperature during atomic layer deposition of HfO{sub 2} on InP  

SciTech Connect (OSTI)

The dependence of the “self cleaning” effect of the substrate oxides on substrate temperature during atomic layer deposition (ALD) of HfO{sub 2} on various chemically treated and native oxide InP (100) substrates is investigated using in situ X-ray photoelectron spectroscopy. The removal of In-oxide is found to be more efficient at higher ALD temperatures. The P oxidation states on native oxide and acid etched samples are seen to change, with the total P-oxide concentration remaining constant, after 10 cycles of ALD HfO{sub 2} at different temperatures. An (NH{sub 4}){sub 2} S treatment is seen to effectively remove native oxides and passivate the InP surfaces independent of substrate temperature studied (200 °C, 250 °C and 300 °C) before and after the ALD process. Density functional theory modeling provides insight into the mechanism of the changes in the P-oxide chemical states.

Dong, H.; Santosh, K.C.; Qin, X.; Brennan, B.; McDonnell, S.; Kim, J. [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States)] [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States); Zhernokletov, D. [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States)] [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States); Hinkle, C. L.; Cho, K.; Wallace, R. M. [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States) [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States); Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States)

2013-10-21T23:59:59.000Z

357

On the electrical stress-induced oxide-trapped charges in thin HfO{sub 2}/SiO{sub 2} gate dielectric stack  

SciTech Connect (OSTI)

Oxide charge buildup and its generation kinetics during constant voltage stress in TaN/HfO{sub 2}/SiO{sub 2}/p-Si structures have been experimentally investigated. From the oxide charge relaxation experiments, nature and energy location of the as-fabricated intrinsic hole traps in the gate stack have also been determined. Our measurement results indicate that the dispersive proton transport through the interfacial SiO{sub 2} contributes larger than hole trapping in positive charge buildup in the stack. From the bias temperature stress measurement results in both control oxide and HfO{sub 2}/SiO{sub 2} stacks, we have identified overcoordinated [Si{sub 2}=OH]{sup +} centers as the proton-induced defects located in the interfacial SiO{sub 2} layer of the stack. Finally, an empirical equation is proposed to explain the stress-induced oxide positive charge buildup.

Samanta, Piyas; Zhu Chunxiang; Chan, Mansun [Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay Road, Kowloon, Hong Kong (China); Department of Electrical and Computer Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260 (Singapore); Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay Road, Kowloon, Hong Kong (China)

2007-09-10T23:59:59.000Z

358

Synchrotron radiation photoemission study of interfacial electronic structure of HfO{sub 2} on In{sub 0.53}Ga{sub 0.47}As(001)-4?×?2 from atomic layer deposition  

SciTech Connect (OSTI)

The growth of a passivating layer on a In{sub 0.53}Ga{sub 0.47}As(001)-4?×?2 surface by atomic-layer deposition of tetrakis[ethylmethylamino]Hafnium (TEMAHf)) followed by the water pulse was investigated by synchrotron radiation photoemission. The Hf atoms maintain four-fold coordination, both after the initial TEMAHf deposition and the subsequent water pulse. The Hf atoms initially bond to the As dangling bonds of the surface As atom located on the edges of the raised ridges. One EMA ligand is removed in this process. Subsequent water exposure substitutes OH ligand for one or more remaining EMA ligands. These in turn react with TEMAHf to form Hf-O-Hf bonds allowing the hafnium oxides to grow. The surface In atoms on the terrace of the raised ridges were partially removed, but none bonded of the precursor atoms. Correlations between the interfacial electronic structure and the electric performance are discussed.

Pi, T. W., E-mail: pi@nsrrc.org.tw, E-mail: gkwer@verizon.net, E-mail: raynien@phys.nthu.edu.tw, E-mail: mhong@phys.ntu.edu.tw [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China); Lin, T. D.; Chang, Y. C.; Hong, M., E-mail: pi@nsrrc.org.tw, E-mail: gkwer@verizon.net, E-mail: raynien@phys.nthu.edu.tw, E-mail: mhong@phys.ntu.edu.tw [Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Lin, H. Y.; Kwo, J., E-mail: pi@nsrrc.org.tw, E-mail: gkwer@verizon.net, E-mail: raynien@phys.nthu.edu.tw, E-mail: mhong@phys.ntu.edu.tw [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Wertheim, G. K., E-mail: pi@nsrrc.org.tw, E-mail: gkwer@verizon.net, E-mail: raynien@phys.nthu.edu.tw, E-mail: mhong@phys.ntu.edu.tw [Woodland Consulting, 175 Woodland Ave., Morristown, New Jersey 07960 (United States)

2014-01-27T23:59:59.000Z

359

Interface effect on dielectric constant of HfO{sub 2}/Al{sub 2}O{sub 3} nanolaminate films deposited by plasma-enhanced atomic layer deposition  

SciTech Connect (OSTI)

The effect of the interface between Al{sub 2}O{sub 3} and HfO{sub 2} sublayers on the dielectric constant was investigated in HfO{sub 2}/Al{sub 2}O{sub 3} nanolaminate films deposited using plasma-enhanced atomic layer deposition. After annealing at 700 deg. C, the dielectric constants of the nanolaminate films with a sublayer thickness of 40 A ring or greater were the same as the calculated values for a series of capacitors consisting of amorphous Al{sub 2}O{sub 3} and monoclinic or tetragonal HfO{sub 2}. As the sublayer thickness was reduced to 10 A, the dielectric constant increased up to 17.7 because a thin Hf-O-Al mixture layer, of which the number increases drastically in the nanolaminate films with thin sublayers, is formed at the interface.

Park, Pan Kwi; Cha, Eun-Soo; Kang, Sang-Won [Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of)

2007-06-04T23:59:59.000Z

360

Interfacial Layer Growth Condition Dependent Electrical Conduction in HfO2/SiO2 Heterostructured Thin Films  

SciTech Connect (OSTI)

The electrical conduction mechanism contributing to the leakage current at different field regions has been studied in this work. The current-voltage (I-V) measurement of TiN/HfO{sub 2}/SiO{sub 2}/P-Si nMOS capacitor has been taken for two different interfacial layer (SiO{sub 2}) growth conditions such as in situ steam grown (ISSG) and chemical processes. It is observed that Poole-Frenkel mechanism is the dominant conduction mechanism in high field region whereas Ohmic conduction is dominant in the low field region. Also it is seen that the gate leakage current is reduced for the devices having chemically grown interfacial layer compared to that of ISSG devices. Both trap energy level ({phi}{sub t}) and activation energy (E{sub a}) increase in the chemically grown interfacial layer devices for the Poole-Frenkel and Ohmic conduction mechanisms respectively in comparison to ISSG devices. Trap energy level ({phi}{sub t}) of {approx} 0.2 eV, obtained from Poole-Frenkel mechanism indicates that the doubly ionized oxygen vacancies (V{sup 2-}) are the active defects and are contributing to the leakage current in these devices.

Sahoo, S. K.; Misra, D.

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Energy band alignment of atomic layer deposited HfO{sub 2} oxide film on epitaxial (100)Ge, (110)Ge, and (111)Ge layers  

SciTech Connect (OSTI)

Crystallographically oriented epitaxial Ge layers were grown on (100), (110), and (111)A GaAs substrates by in situ growth process using two separate molecular beam epitaxy chambers. The band alignment properties of atomic layer hafnium oxide (HfO{sub 2}) film deposited on crystallographically oriented epitaxial Ge were investigated using x-ray photoelectron spectroscopy (XPS). Valence band offset, {Delta}E{sub v} values of HfO{sub 2} relative to (100)Ge, (110)Ge, and (111)Ge orientations were 2.8 eV, 2.28 eV, and 2.5 eV, respectively. Using XPS data, variation in valence band offset, {Delta}E{sub V}(100)Ge>{Delta}E{sub V}(111)Ge>{Delta}E{sub V}(110)Ge, was obtained related to Ge orientation. Also, the conduction band offset, {Delta}E{sub c} relation, {Delta}E{sub c}(110)Ge>{Delta}E{sub c}(111)Ge>{Delta}E{sub c}(100)Ge related to Ge orientations was obtained using the measured bandgap of HfO{sub 2} on each orientation and with the Ge bandgap of 0.67 eV. These band offset parameters for carrier confinement would offer an important guidance to design Ge-based p- and n-channel metal-oxide field-effect transistor for low-power application.

Hudait, Mantu K.; Zhu Yan [Advanced Devices and Sustainable Energy Laboratory (ADSEL), Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

2013-03-21T23:59:59.000Z

362

Effect of Si substrate on interfacial SiO{sub 2} scavenging in HfO{sub 2}/SiO{sub 2}/Si stacks  

SciTech Connect (OSTI)

The scavenging kinetics of an ultra-thin SiO{sub 2} interface layer (SiO{sub 2}-IL) in an HfO{sub 2}/SiO{sub 2}/Si stack is discussed by focusing on the substrate effect in addition to oxygen diffusion. {sup 18}O tracing experiments demonstrate that the O-atom moves from the SiO{sub 2}-IL to the HfO{sub 2} layer during scavenging. SiO{sub 2}-IL scavenging with various substrates (Si, SiC, and sapphire) has been found to be significantly different, which suggests that the Si in the substrate is also necessary to continuously cause the scavenging. Based on these findings and thermodynamic considerations, a kinetic model where oxygen vacancy (V{sub O}) transferred from the HfO{sub 2} reacts with the SiO{sub 2}, which is in contact with the Si-substrate, is proposed for the SiO{sub 2}-IL scavenging.

Li, Xiuyan, E-mail: xiuyan@adam.t.u-tokyo.ac.jp; Yajima, Takeaki; Nishimura, Tomonori; Nagashio, Kosuke; Toriumi, Akira [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656 (Japan)

2014-11-03T23:59:59.000Z

363

Formation of the dopant-oxygen vacancy complexes and its influence on the photoluminescence emissions in Gd-doped HfO{sub 2}  

SciTech Connect (OSTI)

Rare earth doping is widely used to improve the desired properties of high-k dielectric oxides. However, whether rare earth doping can suppress the formation of oxygen vacancies is still debated. By using the first-principles calculations with the generalized gradient approximation and more advanced hybrid functional, we have investigated the structural and electronic properties of the dopant-oxygen vacancy complexes in Gd-doped HfO{sub 2}. Our calculations indicate that the Gd dopants interacting with oxygen vacancies can substantially shift up the V{sub O} energy states towards the conduction band edge. This together with other effects, such as capturing the localized electrons at the oxygen vacancy by Gd dopants and suppressing the randomicity of oxygen vacancy formation, improves the reliability of the devices made from Gd-doped HfO{sub 2}. Based on our calculated results, we have presented an explanation for the experimentally observed decrease of the V{sub O}-related photoluminescence intensities upon Gd doping in HfO{sub 2}.

Wang, L. G.; Tu, H. L.; Xiong, Y. H.; Du, J.; Wang, J. W.; Huang, G. J. [General Research Institute for Nonferrous Metals, Beijing 100088 (China); Xiao, W. [General Research Institute for Nonferrous Metals, Beijing 100088 (China); University of Science and Technology Beijing, Beijing 100083 (China)

2014-09-28T23:59:59.000Z

364

Realization of high-quality HfO{sub 2} on In{sub 0.53}Ga{sub 0.47}As by in-situ atomic-layer-deposition  

SciTech Connect (OSTI)

High {kappa} dielectric of HfAlO/HfO{sub 2} was an in-situ atomic-layer-deposited directly on molecular beam epitaxy grown In{sub 0.53}Ga{sub 0.47}As surface without using pre-treatments or interfacial passivation layers, where HfAlO (HfO{sub 2}:Al{sub 2}O{sub 3} {approx} 4:1) with high re-crystallization temperature was employed as the top oxide layer. The HfAlO ({approx}4.5 nm)/HfO{sub 2} (0.8 nm)/In{sub 0.53}Ga{sub 0.47}As metal oxide semiconductor capacitors have exhibited an oxide/In{sub 0.53}Ga{sub 0.47}As interface free of arsenic-related defective bonding, thermodynamic stability at 800 deg. C, and low leakage current densities of <10{sup -7} A/cm{sup 2} at {+-}1 MV/cm. The interfacial trap density (D{sub it}) spectra in absence of mid-gap peaks were obtained by temperature-dependent capacitance and conductance with D{sub it}'s of 2-3 x 10{sup 12} eV{sup -1} cm{sup -2} below and 6-12 x 10{sup 11} eV{sup -1} cm{sup -2} above the mid-gap of In{sub 0.53}Ga{sub 0.47}As, respectively. An equivalent oxide thickness of less than 1 nm has been achieved by reducing the HfAlO thickness to {approx}2.7 nm with the same initial HfO{sub 2} thickness of {approx}0.8 nm.

Lin, T. D.; Hong, M. [Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Chang, Y. H. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lin, C. A.; Huang, M. L.; Lee, W. C. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Kwo, J. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China)

2012-04-23T23:59:59.000Z

365

Process for producing ethanol from syngas  

DOE Patents [OSTI]

The invention provides a method for producing ethanol, the method comprising establishing an atmosphere containing methanol forming catalyst and ethanol forming catalyst; injecting syngas into the atmosphere at a temperature and for a time sufficient to produce methanol; and contacting the produced methanol with additional syngas at a temperature and for a time sufficient to produce ethanol. The invention also provides an integrated system for producing methanol and ethanol from syngas, the system comprising an atmosphere isolated from the ambient environment; a first catalyst to produce methanol from syngas wherein the first catalyst resides in the atmosphere; a second catalyst to product ethanol from methanol and syngas, wherein the second catalyst resides in the atmosphere; a conduit for introducing syngas to the atmosphere; and a device for removing ethanol from the atmosphere. The exothermicity of the method and system obviates the need for input of additional heat from outside the atmosphere.

Krause, Theodore R; Rathke, Jerome W; Chen, Michael J

2013-05-14T23:59:59.000Z

366

California: Agricultural Residues Produce Renewable Fuel | Department...  

Energy Savers [EERE]

that validated the viability of this technology platform for producing cellulosic ethanol from corn stover at reasonable yields. The California Energy Commission has awarded...

367

Fracture characteristics and their relationships to producing...  

Open Energy Info (EERE)

area Jump to: navigation, search OpenEI Reference LibraryAdd to library Book: Fracture characteristics and their relationships to producing zones in deep wells, Raft River...

368

Scientists produce transparent, light-harvesting material  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Transparent, light-harvesting material Scientists produce transparent, light-harvesting material The material could be used in development of transparent solar panels. November 3,...

369

Effects of in situ N{sub 2} plasma treatment on etch of HfO{sub 2} in inductively coupled Cl{sub 2}/N{sub 2} plasmas  

SciTech Connect (OSTI)

The etch selectivity of HfO{sub 2} to Si reported to date is poor. To improve the selectivity, one needs to either increase the etch rate of HfO{sub 2} or decrease the etch rate of Si. In this work, the authors investigate the etch selectivity of HfO{sub 2} in Cl{sub 2}/N{sub 2} plasmas. In particular, the effects of in situ N{sub 2} plasma treatment of HfO{sub 2} and Si were investigated. The silicon substrate was exposed to nitrogen plasma and was nitrided, which was confirmed by x-ray photoelectron spectroscopy. The nitrided Si etching was suppressed in Cl{sub 2}/N{sub 2} plasmas. The effectiveness of nitridation was studied with varying the plasma power, bias power, pressure, and N{sub 2} plasma exposure time. The results show that the etch resistance increased with increased power and decreased pressure. A minimum exposure time was required to obtain etch resistant property. The applied bias power increased the etch rate of Si substrate, so it should not be used during N{sub 2} plasma treatment. Fortunately, the etch rate of HfO{sub 2} was increased by the nitridation process. Therefore, HfO{sub 2}/Si selectivity can be improved by nitridation and became higher than 5 under proper exposure condition.

Lin Chaung; Leou, K.-C.; Fan, Y.-C.; Li, T.-C.; Chang, K.-H.; Lee, L.-S.; Tzeng, P.-J. [Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30043, Taiwan (China); Electronic Research and Service Organization, Industrial Technology Research Institute, Hsinchu 30043, Taiwan (China)

2007-05-15T23:59:59.000Z

370

Method for producing microporous metal bodies  

DOE Patents [OSTI]

Tungsten is vapor-deposited by hydrogen reduction of tungsten hexafluoride (WF.sub.6) to produce a tungsten body having from 40 to 100 ppm fluorine. The tungsten is then heated under vacuum to produce grain boundary porosity for a sufficient period of time to allow the pores along the grain boundaries to become interconnected.

Danko, Joseph C. (Danville, CA)

1982-01-01T23:59:59.000Z

371

PRODUCER -SCROUNGER GAME n-Person Game  

E-Print Network [OSTI]

size, ESS frequency of scrounging Assumptions of Producer-Scrounger Game Fix group (or population size Producer invades Scrounger n-Person Game with ESS q* : 0 ESS ** q P q S dq dW dq dW ESS frequency of scrounger

Caraco, Thomas

372

Release of UF/sub 6/ from a ruptured model 48Y cylinder at Sequoyah Fuels Corporation Facility: lessons-learned report  

SciTech Connect (OSTI)

The uranium hexafluoride (UF/sub 6/) release of January 4, 1986, at the Sequoyah Fuels Corporation facility has been reviewed by a NRC Lessons-Learned Group. A Model 48Y cylinder containing UF/sub 6/ ruptured upon being heated after it was grossly overfilled. The UF/sub 6/ released upon rupture of the cylinder reacted with airborne moisture to produce hydrofluoric acid (HF) and uranyl fluoride (UO/sub 2/F/sub 2/). One individual died from exposure to airborne HF and several others were injured. There were no significant immediate effects from exposure to uranyl fluoride. This supplement report contains NRC's response to the recommendations made in NUREG-1198 by the Lessons Learned Group. In developing a response to each of the recommendations, the staff considered actions that should be taken: (1) for the restart of the Sequoyah Fuels Facility; (2) to make near-term improvement; and (3) to improve the regulatory framework.

Not Available

1986-08-01T23:59:59.000Z

373

Spectral optical properties of selected photosynthetic microalgae producing biofuels  

E-Print Network [OSTI]

Photosynthetic Microalgae Producing Biofuels Euntaek Lee,Photosyn- thetic Microalgae Producing Biofuels”, Journal of

Lee, Euntaek; Heng, Ri-Liang; Pilon, Laurent

2013-01-01T23:59:59.000Z

374

E-Print Network 3.0 - alloy sheets produced Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

tantalum-base alloys (e... .g. Ta-8W-2Hf), niobium alloys (Nb-1Zr), and molybdenum and tungsten alloys. The results are compared... operating temperature window for structural...

375

Producing a computer generated explosive effect  

E-Print Network [OSTI]

is conducted in order to produce a convincing explosive effect with a computer. A description of the current state of the art provides current achievements by industry and individual artists. A tutorial focusing on modeling, lighting, and setting up animation...

Mao, Wei

1999-01-01T23:59:59.000Z

376

Table of Contents Producing Hydrogen................1  

E-Print Network [OSTI]

. It can store the energy from diverse domestic resources (including clean coal, nuclear renewable resources, nuclear energy, and coal with carbon capture and storage. 1 #12;Potential for clean1 #12;Table of Contents Producing Hydrogen................1 Hydrogen Production Technologies

377

Coal seam natural gas producing areas (Louisiana)  

Broader source: Energy.gov [DOE]

In order to prevent waste and to avoid the drilling of unnecessary wells and to encourage the development of coal seam natural gas producing areas in Louisiana, the commissioner of conservation is...

378

Producing tritium in a homogenous reactor  

DOE Patents [OSTI]

A method and apparatus are described for the joint production and separation of tritium. Tritium is produced in an aqueous homogenous reactor and heat from the nuclear reaction is used to distill tritium from the lower isotopes of hydrogen.

Cawley, William E. (Richland, WA)

1985-01-01T23:59:59.000Z

379

Producing X-rays at the APS  

ScienceCinema (OSTI)

An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest X-ray beams in the Western Hemisphere, and the research carried out by scientists using those X-rays.

None

2013-04-19T23:59:59.000Z

380

Methods and systems for producing syngas  

DOE Patents [OSTI]

Methods and systems are provided for producing syngas utilizing heat from thermochemical conversion of a carbonaceous fuel to support decomposition of at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells. Simultaneous decomposition of carbon dioxide and water or steam by one or more solid-oxide electrolysis cells may be employed to produce hydrogen and carbon monoxide. A portion of oxygen produced from at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells is fed at a controlled flow rate in a gasifier or combustor to oxidize the carbonaceous fuel to control the carbon dioxide to carbon monoxide ratio produced.

Hawkes, Grant L; O'Brien, James E; Stoots, Carl M; Herring, J. Stephen; McKellar, Michael G; Wood, Richard A; Carrington, Robert A; Boardman, Richard D

2013-02-05T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Produced Water Management and Beneficial Use  

SciTech Connect (OSTI)

Large quantities of water are associated with the production of coalbed methane (CBM) in the Powder River Basin (PRB) of Wyoming. The chemistry of co-produced water often makes it unsuitable for subsequent uses such as irrigated agriculture. However, co-produced waters have substantial potential for a variety of beneficial uses. Achieving this potential requires the development of appropriate water management strategies. There are several unique characteristics of co-produced water that make development of such management strategies a challenge. The production of CBM water follows an inverse pattern compared to traditional wells. CBM wells need to maintain low reservoir pressures to promote gas production. This need renders the reinjection of co-produced waters counterproductive. The unique water chemistry of co-produced water can reduce soil permeability, making surface disposal difficult. Unlike traditional petroleum operations where co-produced water is an undesirable by-product, co-produced water in the PRB often is potable, making it a highly valued resource in arid western states. This research project developed and evaluated a number of water management options potentially available to CBM operators. These options, which focus on cost-effective and environmentally-sound practices, fall into five topic areas: Minimization of Produced Water, Surface Disposal, Beneficial Use, Disposal by Injection and Water Treatment. The research project was managed by the Colorado Energy Research Institute (CERI) at the Colorado School of Mines (CSM) and involved personnel located at CERI, CSM, Stanford University, Pennsylvania State University, the University of Wyoming, the Argonne National Laboratory, the Gas Technology Institute, the Montana Bureau of Mining and Geology and PVES Inc., a private firm.

Terry Brown; Carol Frost; Thomas Hayes; Leo Heath; Drew Johnson; David Lopez; Demian Saffer; Michael Urynowicz; John Wheaton; Mark Zoback

2007-10-31T23:59:59.000Z

382

Identification and evaluation of alternatives for the disposition of fluoride fuel and flush salts from the molten salt reactor experiment at Oak Ridge National Laboratory, Oak Ridge, Tennessee  

SciTech Connect (OSTI)

This document presents an initial identification and evaluation of the alternatives for disposition of the fluoride fuel and flush salts stored in the drain tanks at the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory (ORNL). It will serve as a resource for the U.S. Department of Energy contractor preparing the feasibility study for this activity under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). This document will also facilitate further discussion on the range of credible alternatives, and the relative merits of alternatives, throughout the time that a final alternative is selected under the CERCLA process.

NONE

1996-08-15T23:59:59.000Z

383

Negative effect of crystallization on the mechanism of laser damage in a HfO{sub 2}/SiO{sub 2} multilayer  

SciTech Connect (OSTI)

Elucidation of the mechanisms of laser damage is indispensable in realizing high resistance mirrors for the next generation of ultra-short pulse high intensity lasers. In this study, the surface and a section of the laser-damaged area of a laser mirror were observed with a laser microscope and a transmission electron microscope (cross-sectional TEM), respectively. A grain boundary of HfO{sub 2} microcrystal was observed in the damaged area. This observation and an evaluation of the mirror's damage resistance showed that the formation of crystals in the multilayer mirror is one of the major determinants of damage resistance.

Tateno, Ryo [Shimadzu Corporation, 1, Nishinokyo-Kuwabaracho Nakagyo-ku, Kyoto 604-8511 (Japan); Okada, Hajime; Otobe, Tomohito; Kawase, Keigo; Koga, James K.; Kosuge, Atsushi; Nagashima, Keisuke; Sugiyama, Akira [Kansai Photon Science Institute, Japan Atomic Energy Agency, 8-1-7 Umemidai, Kizugawa-shi, Kyoto 619-0215 (Japan); Kashiwagi, Kunihiro [Department of Electrical and Communication Engineering, Faculty of Engineering, Toyo University, 2100, Kujirai Kawagoe-shi, Saitama 350-8585 (Japan)

2012-12-15T23:59:59.000Z

384

Looking for footprint of bulk metallic glass in electronic and phonon heat capacities of Cu{sub 55}Hf{sub 45?x}Ti{sub x} alloys  

SciTech Connect (OSTI)

We report on the heat capacity investigation of Cu{sub 55}Hf{sub 45?x}Ti{sub x} metallic glasses. The most appropriate procedure to estimate low temperature electronic and phonon contributions has been determined. Both contributions exhibit monotonous Ti concentration dependence, demonstrating that there is no relation of either the electron density of states at the Fermi level or the Debye temperature to the increased glass forming ability in the Ti concentration range x?=?15–30. The thermodynamic parameters (e.g., reduced glass temperature) remain better indicators in assessing the best composition for bulk metallic glass formation.

Remenyi, G. [Institut Néel, Université Grenoble Alpes, F-38042 Grenoble (France); CNRS, Institut Néel, F-38042 Grenoble (France); Biljakovi?, K. [CNRS, Institut Néel, F-38042 Grenoble (France); Institute of Physics, Bijeni?ka c. 46, P.O. Box 304, HR-10001 Zagreb (Croatia); Starešini?, D.; Dominko, D., E-mail: ddominko@ifs.hr [Institute of Physics, Bijeni?ka c. 46, P.O. Box 304, HR-10001 Zagreb (Croatia); Risti?, R. [Department of Physics, Trg Lj. Gaja 6, HR-31000 Osijek (Croatia); Babi?, E. [Department of Physics, Faculty of Science, Bijeni?ka c. 32, HR-10000 Zagreb (Croatia); Figueroa, I. A. [Institute for Materials Research-UNAM, Ciudad Universitaria Coyoacan, C.P. 04510 Mexico D.F. (Mexico); Davies, H. A. [Department of Engineering Materials, University of Sheffield, Sheffield S1 3JD (United Kingdom)

2014-04-28T23:59:59.000Z

385

ANAEROBIC BIOLOGICAL TREATMENT OF PRODUCED WATER  

SciTech Connect (OSTI)

During the production of oil and gas, large amounts of water are brought to the surface and must be disposed of in an environmentally sensitive manner. This is an especially difficult problem in offshore production facilities where space is a major constraint. The chief regulatory criterion for produced water is oil and grease. Most facilities have little trouble meeting this criterion using conventional oil-water separation technologies. However, some operations have significant amounts of naphthenic acids in the water that behave as oil and grease but are not well removed by conventional technologies. Aerobic biological treatment of naphthenic acids in simulated-produced water has been demonstrated by others; however, the system was easily overloaded by the large amounts of low-molecular-weight organic acids often found in produced waters. The objective of this research was to determine the ability of an anaerobic biological system to treat these organic acids in a simulated produced water and to examine the potential for biodegradation of the naphthenic acids in the anaerobic environment. A small fixed-film anaerobic biological reactor was constructed and adapted to treat a simulated produced water. The bioreactor was tubular, with a low-density porous glass packing material. The inocula to the reactor was sediment from a produced-water holding pond from a municipal anaerobic digester and two salt-loving methanogenic bacteria. During start-up, the feed to the reactor contained glucose as well as typical produced-water components. When glucose was used, rapid gas production was observed. However, when glucose was eliminated and the major organic component was acetate, little gas was generated. Methane production from acetate may have been inhibited by the high salt concentrations, by sulfide, or because of the lack, despite seeding, of microbes capable of converting acetate to methane. Toluene, a minor component of the produced water (0.1 g/L) was removed in the reactor. Batch tests were conducted to examine naphthenic acid biodegradability under several conditions. The conditions used were seed from the anaerobic reactor, wetland sediments under aerobic and anaerobic conditions, and a sterile control. The naphthenic acid was from a commercial source isolated from Gulf Coast petroleum as was dosed at 2 mg/mL. The incubations were for 30 days at 30 C. The results showed that the naphthenic acids were not biodegraded under anaerobic conditions, but were degraded under aerobic conditions. Despite poor performance of the anaerobic reactor, it remains likely that anaerobic treatment of acetate, toluene, and, potentially, other produced-water components is feasible.

John R. Gallagher

2001-07-31T23:59:59.000Z

386

Air bubbles clean produced water for reinjection  

SciTech Connect (OSTI)

The reuse of produced water in a waterflood may be hazardous to the health and wealth of the reservoir. Disposal of produced water and finding a new source of water for a waterflood can double your costs. Air flotation is being tested to rehabilitate produced water on a lease in eastern Kansas. The use of air flotation in the oil field is at least forty years old. However, many operators are reluctant to spend the capital for surface equipment to assure a supply of good quality water for their waterflood operation. Before the installation of the air flotation unit only the produced water was filtered through a 75-micron bag and the filter water was then added to the make-up water. Seventy-five micron cartridge filters were used at the wellhead. Both the plant and wellhead filters required frequent replacement. Injection wells averaged more than one cleaning and acidization per year. Since installation of the air flotation unit, the combined produced and makeup water is passed through either a 25-or 10-micron bag filter in the plant and a 10-micron cartridge at the wellhead. The results of the test being conducted by an independent oil operator show a reduction in the cost for the water injection system. This study is part of the Department of Energy Class I PONS with independent oil operators.

Michnick, M.J. [Univ. of Kansas, Lawrence, KS (United States)

1995-12-31T23:59:59.000Z

387

Methods for producing reinforced carbon nanotubes  

DOE Patents [OSTI]

Methods for producing reinforced carbon nanotubes having a plurality of microparticulate carbide or oxide materials formed substantially on the surface of such reinforced carbon nanotubes composite materials are disclosed. In particular, the present invention provides reinforced carbon nanotubes (CNTs) having a plurality of boron carbide nanolumps formed substantially on a surface of the reinforced CNTs that provide a reinforcing effect on CNTs, enabling their use as effective reinforcing fillers for matrix materials to give high-strength composites. The present invention also provides methods for producing such carbide reinforced CNTs.

Ren, Zhifen (Newton, MA); Wen, Jian Guo (Newton, MA); Lao, Jing Y. (Chestnut Hill, MA); Li, Wenzhi (Brookline, MA)

2008-10-28T23:59:59.000Z

388

Solid fuel volatilization to produce synthesis gas  

DOE Patents [OSTI]

A method comprising contacting a carbon and hydrogen-containing solid fuel and a metal-based catalyst in the presence of oxygen to produce hydrogen gas and carbon monoxide gas, wherein the contacting occurs at a temperature sufficiently high to prevent char formation in an amount capable of stopping production of the hydrogen gas and the carbon monoxide gas is provided. In one embodiment, the metal-based catalyst comprises a rhodium-cerium catalyst. Embodiments further include a system for producing syngas. The systems and methods described herein provide shorter residence time and high selectivity for hydrogen and carbon monoxide.

Schmidt, Lanny D.; Dauenhauer, Paul J.; Degenstein, Nick J.; Dreyer, Brandon J.; Colby, Joshua L.

2014-07-29T23:59:59.000Z

389

Fluoride (F) is not taken up by Salmonella typhimurium TA98 (TA98), used for Ames mutagenicity test, unless aluminum (Al) is present  

SciTech Connect (OSTI)

TA98 is commonly used for the Ames test to detect frame-shift mutations. Ames test results for fluoride mutagenicity are controversial. Since Al and F, both present in finished drinking water, form a stable complex, the authors determined the effect of Al on F uptake by TA98 to evaluate any Al effect on Ames test results for F. A known number of TA98 in 0.1M potassium phosphate buffer was incubated with various concentrations of Al, F or aluminum fluoride for 1 hr at 37C in a shaking incubator. The cells were washed twice in potassium phosphate buffer and then resuspended in water. After breaking the cells open by sonication, the resulting supernatant was analyzed for Al by graphite furnace atomic absorption and for F using a F ion-selective electrode. Al accumulated in a concentration-dependent manner to 4.5 ppm then decreased rapidly as the Al was increased to 9 ppm. Intracellular F was below the limit of detection even when the medium contained 590 ppm F. However, F was taken up from media containing greater than 200 ppm F, providing that aluminum was also present. The authors conclude that the Ames test, using TA98, is not suitable for the detection of F mutagenicity.

Ahn, H.W.; Jeffery, E.H. (Univ. of Illinois, Urbana (United States))

1991-03-11T23:59:59.000Z

390

Feedback control of HfO{sub 2} etch processing in inductively coupled Cl{sub 2}/N{sub 2}/Ar plasmas  

SciTech Connect (OSTI)

The etch rate of HfO{sub 2} etch processing has been feedback controlled in inductively coupled Cl{sub 2}/N{sub 2}/Ar plasmas. The ion current and the root mean square rf voltage on the wafer stage, which are measured using a commercial impedance meter connected to the wafer stage, are chosen as controlled variables because the positive-ion flux and ion energy incident upon the wafer surface are the key factors that determine the etch rate. Two 13.56 MHz rf generators are used to adjust the inductively coupled plasma power and bias power which control ion density and ion energy, respectively. The adopted HfO{sub 2} etch processing used rather low rf voltage. The ion-current value obtained by the power/voltage method is underestimated, so the neural-network model was developed to assist estimating the correct ion-current value. The experimental results show that the etch-rate variation of the closed-loop control is smaller than that of the open-loop control. However, the first wafer effect cannot be eliminated using closed-loop control and thus to achieve a constant etch rate, the chamber-conditioning procedure is required in this etch processing.

Lin Chaung; Leou, K.-C.; Li, T.-C.; Lee, L.-S.; Tzeng, P.-J. [Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan 30043 (China); Electronic Research and Service Organization, Industrial Technology Research Institute, Hsinchu, Taiwan 310 (China)

2008-09-15T23:59:59.000Z

391

Mechanism for atmosphere dependence of laser damage morphology in HfO{sub 2}/SiO{sub 2} high reflective films  

SciTech Connect (OSTI)

We show in this paper single-shot and multi-shot laser-induced damage thresholds (LIDTs) of HfO{sub 2}/SiO{sub 2} high reflective films (the reflectance = 99.9%) are affected by the presence of a water layer absorbed on the surface of the porous films. When the water layer was removed with the process of pumping, the single-shot LIDT measured in vacuum dropped to {approx}48% of that measured in air, while the multi-shot LIDT in vacuum dropped to {approx}47% of its atmospheric value for the high reflective films. Typical damage micrographs of the films in air and in vacuum were obtained, showing distinct damage morphologies. Such atmosphere dependence of the laser damage morphology was found to originate from that formation of a water layer on the surface of porous films could cause an increase of horizontal thermal conductivity and a reduction of vertical thermal conductivity. Moreover, laser-induced periodic ripple damages in air were found in the SiO{sub 2} layer from the micrographs. A model of deformation kinematics was used to illustrate the occurrence of the periodic ripple damage, showing that it could be attributed to a contraction of the HfO{sub 2} layer under irradiation by the 5-ns laser pulses in air.

Pu Yunti [Fine Optical Engineering Research Center, Chengdu 610041 (China); Department of Materials Science, Sichuan University, Chengdu 610064 (China); Ma Ping; Chen Songlin; Wang Gang; Pan Feng [Fine Optical Engineering Research Center, Chengdu 610041 (China); Zhu Jiliang; Sun Ping; Zhu Xiaohong; Zhu Jianguo; Xiao Dingquan [Department of Materials Science, Sichuan University, Chengdu 610064 (China)

2012-07-15T23:59:59.000Z

392

X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy investigation of Al-related dipole at the HfO{sub 2}/Si interface  

SciTech Connect (OSTI)

The presence of an ultrathin oxide layer at the high-k/SiO{sub 2} interface may result in an interfacial dipole related to the specific high-k dielectric used for the gate stacks. 1 nm HfO{sub 2}/x nmAl{sub 2}O{sub 3}/SiO{sub 2}/Si stacks with different x values (x=0, 0.4, 0.8, 1.2) have been prepared by atomic layer deposition. Using photoelectron spectroscopy, an Al-related interfacial dipole in the HfO{sub 2}/Al{sub 2}O{sub 3}/SiO{sub 2} gate stack has been identified. X-ray photoelectron spectroscopy analysis shows that the dipole is correlated with the formation of an interfacial Al-silicate. The dipole is located at the Al-silicate interface between Al{sub 2}O{sub 3} and SiO{sub 2}, and its strength increases with the increase in Al{sub 2}O{sub 3} thickness because of Al silicate growth. Such Al-related interfacial dipole should have potential applications in future positive metal-oxide-semiconductor devices.

Zhu, L. Q.; Barrett, N.; Jegou, P. [Groupe Photoemission, CEA/IRAMIS/SPCSI, F-91191 Gif-sur-Yvette (France); Martin, F.; Leroux, C.; Martinez, E.; Grampeix, H.; Renault, O.; Chabli, A. [CEA-LETI, MINATEC, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)

2009-01-15T23:59:59.000Z

393

Positive bias temperature instability in p-type metal-oxide-semiconductor devices with HfSiON/SiO{sub 2} gate dielectrics  

SciTech Connect (OSTI)

We present a detailed investigation on positive-bias temperature stress (PBTS) induced degradation of nitrided hafnium silicate (HfSiON)/SiO{sub 2} gate stack in n{sup +}-poly crystalline silicon (polySi) gate p-type metal-oxide-semiconductor (pMOS) devices. The measurement results indicate that gate dielectric degradation is a composite effect of electron trapping in as-fabricated as well as newly generated neutral traps, resulting a significant amount of stress-induced leakage current and generation of surface states at the Si/SiO{sub 2} interface. Although, a significant amount of interface states are created during PBTS, the threshold voltage (V{sub T}) instability of the HfSiON based pMOS devices is primarily caused by electron trapping and detrapping. It is also shown that PBTS creates both acceptor- and donor-like interface traps via different depassivation mechanisms of the Si{sub 3}???SiH bonds at the Si/SiO{sub 2} interface in pMOS devices. However, the number of donor-like interface traps ?N{sub it}{sup D} is significantly greater than that of acceptor-like interface traps ?N{sup A}{sub it}, resulting the PBTS induced net interface traps as donor-like.

Samanta, Piyas, E-mail: piyas@vcfw.org [Department of Physics, Vidyasagar College for Women, 39 Sankar Ghosh Lane, Kolkata 700 006 (India); Huang, Heng-Sheng; Chen, Shuang-Yuan [Institute of Mechatronic Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 106, Taiwan (China); Liu, Chuan-Hsi [Department of Mechatronic Technology, National Taiwan Normal University, No. 162, Sec. 1, He-Ping E. Rd., Taipei 106, Taiwan (China); Cheng, Li-Wei [Central R and D Division, United Microelectronics Corporation, No. 3, Li-Hsin Rd. II, Hsinchu 300, Taiwan (China)

2014-02-21T23:59:59.000Z

394

SOVIETS BUILD MACHINES TO PRODUCE KRILL PASTE'  

E-Print Network [OSTI]

EUROPE SOVIETS BUILD MACHINES TO PRODUCE KRILL PASTE' The Soviet Federal Research Institute of Fisheries and Oceanography ( V N I R 0) has built machines for production of a protein- rich paste from protein paste from Black Sea shrimp. Each machine, operated by 2 people, has a processing capacity of 1

395

Producing dicarboxylic acids using polyketide synthases  

DOE Patents [OSTI]

The present invention provides for a polyketide synthase (PKS) capable of synthesizing a dicarboxylic acid (diacid). Such diacids include diketide-diacids and triketide-diacids. The invention includes recombinant nucleic acid encoding the PKS, and host cells comprising the PKS. The invention also includes methods for producing the diacids.

Katz, Leonard; Fortman, Jeffrey L; Keasling, Jay D

2013-10-29T23:59:59.000Z

396

New techniques for producing thin boron films  

SciTech Connect (OSTI)

A review will be presented of methods for producing thin boron films using an electron gun. Previous papers have had the problem of spattering of the boron source during the evaporation. Methods for reducing this problem will also be presented. 12 refs., 4 figs.

Thomas, G.E.

1988-01-01T23:59:59.000Z

397

Performance Profiles of Major Energy Producers  

Reports and Publications (EIA)

The information and analyses in Performance Profiles of Major Energy Producers is intended to provide a critical review, and promote an understanding, of the possible motivations and apparent consequences of investment decisions made by some of the largest corporations in the energy industry.

2011-01-01T23:59:59.000Z

398

Metrics for a Sustainable Produced By  

E-Print Network [OSTI]

Metrics for a Sustainable EcoVillage #12;2 Produced By: Nam Nguyen Master of Urban and Regional Project Manager Project for Pride in Living (PPL) Jeffrey Skrenes Housing Director Hawthorne Neighborhood Council Photo source: Unless otherwise noted, photos are provided by People for Pride in Living

Levinson, David M.

399

Beneficial Reuse of San Ardo Produced Water  

SciTech Connect (OSTI)

This DOE funded study was performed to evaluate the potential for treatment and beneficial reuse of produced water from the San Ardo oilfield in Monterey County, CA. The potential benefits of a successful full-scale implementation of this project include improvements in oil production efficiency and additional recoverable oil reserves as well as the addition of a new reclaimed water resource. The overall project was conducted in two Phases. Phase I identified and evaluated potential end uses for the treated produced water, established treated water quality objectives, reviewed regulations related to treatment, transport, storage and use of the treated produced water, and investigated various water treatment technology options. Phase II involved the construction and operation of a small-scale water treatment pilot facility to evaluate the process's performance on produced water from the San Ardo oilfield. Cost estimates for a potential full-scale facility were also developed. Potential end uses identified for the treated water include (1) agricultural use near the oilfield, (2) use by Monterey County Water Resources Agency (MCWRA) for the Salinas Valley Water Project or Castroville Seawater Intrusion Project, (3) industrial or power plant use in King City, and (4) use for wetlands creation in the Salinas Basin. All of these uses were found to have major obstacles that prevent full-scale implementation. An additional option for potential reuse of the treated produced water was subsequently identified. That option involves using the treated produced water to recharge groundwater in the vicinity of the oil field. The recharge option may avoid the limitations that the other reuse options face. The water treatment pilot process utilized: (1) warm precipitation softening to remove hardness and silica, (2) evaporative cooling to meet downstream temperature limitations and facilitate removal of ammonia, and (3) reverse osmosis (RO) for removal of dissolved salts, boron, and organics. Pilot study results indicate that produced water from the San Ardo oilfield can be treated to meet project water quality goals. Approximately 600 mg/l of caustic and 100 mg/l magnesium dosing were required to meet the hardness and silica goals in the warm softening unit. Approximately 30% of the ammonia was removed in the cooling tower; additional ammonia could be removed by ion exchange or other methods if necessary. A brackish water reverse osmosis membrane was effective in removing total dissolved solids and organics at all pH levels evaluated; however, the boron treatment objective was only achieved at a pH of 10.5 and above.

Robert A. Liske

2006-07-31T23:59:59.000Z

400

Effects of CO{sub 2} activation on electrochemical performance of microporous carbons derived from poly(vinylidene fluoride)  

SciTech Connect (OSTI)

In this work, we have prepared microporous carbons (MPCs) derived from poly(vinylidene fluoride) (PVDF), and the physical activation of MPCs using CO{sub 2} gas is subsequently carried out with various activation temperatures to investigate the electrochemical performance. PVDF is successfully converted into MPCs with a high specific surface area and well-developed micropores. After CO{sub 2} activation, the specific surface areas of MPCs (CA-MPCs) are enhanced by 12% compared with non-activated MPCs. With increasing activation temperature, the micropore size distributions of A-MPCs also become narrower and shift to larger pore size. It is also confirmed that the CO{sub 2} activation had developed the micropores and introduced the oxygen-containing groups to MPCs? surfaces. From the results, the specific capacitances of the electrodes in electric double layer capacitors (EDLCs) based on CA-MPCs are distinctly improved through CO{sub 2} activation. The highest specific capacitance of the A-MPCs activated at 700 °C is about 125 F/g, an enhancement of 74% in comparison with NA-MPCs, at a discharge current of 2 A/g in a 6 M KOH electrolyte solution. We also found that micropore size of 0.67 nm has a specific impact on the capacitance behaviors, besides the specific surface area of the electrode samples. - Graphical abstract: The A-MPC samples with high specific surface area (ranging from 1030 to 1082 m{sup 2}/g), corresponding to micropore sizes of 0.67 and 0.72 nm, and with the amount of oxygen-containing groups ranging from 3.2% to 4.4% have been evaluated as electrodes for EDLC applications. . Display Omitted - Highlights: • Microporous carbons (MPCs) were synthesized without activation process. • Next, we carried out the CO{sub 2} activation of MPCs with activation temperatures. • It had developed the micropores and introduced the O-functional groups to MPCs. • The highest specific capacitance: 125 F/g, an increase of 74% compared to MPCs.

Lee, Seul-Yi; Park, Soo-Jin, E-mail: sjpark@inha.ac.kr

2013-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Characterization of aerosols produced by surgical procedures  

SciTech Connect (OSTI)

In many surgeries, especially orthopedic procedures, power tools such as saws and drills are used. These tools may produce aerosolized blood and other biological material from bone and soft tissues. Surgical lasers and electrocautery tools can also produce aerosols when tissues are vaporized and condensed. Studies have been reported in the literature concerning production of aerosols during surgery, and some of these aerosols may contain infectious material. Garden et al. (1988) reported the presence of papilloma virus DNA in the fumes produced from laser surgery, but the infectivity of the aerosol was not assessed. Moon and Nininger (1989) measured the size distribution and production rate of emissions from laser surgery and found that particles were generally less than 0.5 {mu}m diameter. More recently there has been concern expressed over the production of aerosolized blood during surgical procedures that require power tools. In an in vitro study, the production of an aerosol containing the human immunodeficiency virus (HIV) was reported when power tools were used to cut tissues with blood infected with HIV. Another study measured the size distribution of blood aerosols produced by surgical power tools and found blood-containing particles in a number of size ranges. Health care workers are anxious and concerned about whether surgically produced aerosols are inspirable and can contain viable pathogens such as HIV. Other pathogens such as hepatitis B virus (HBV) are also of concern. The Occupational Safety and Health funded a project at the National Institute for Inhalation Toxicology Research Institute to assess the extent of aerosolization of blood and other tissues during surgical procedures. This document reports details of the experimental and sampling approach, methods, analyses, and results on potential production of blood-associated aerosols from surgical procedures in the laboratory and in the hospital surgical suite.

Yeh, H.C.; Muggenburg, B.A.; Lundgren, D.L.; Guilmette, R.A.; Snipes, M.B.; Jones, R.K. [Inhalation Toxicology Research Institute, Albuquerque, NM (United States); Turner, R.S. [Lovelace Health Systems, Albuquerque, NM (United States)

1994-07-01T23:59:59.000Z

402

Spectral optical properties of selected photosynthetic microalgae producing biofuels  

E-Print Network [OSTI]

Biochemical composition of microalgae from the green algalof Selected Photosynthetic Microalgae Producing Biofuelsof Selected Photosyn- thetic Microalgae Producing Biofuels”,

Lee, Euntaek; Heng, Ri-Liang; Pilon, Laurent

2013-01-01T23:59:59.000Z

403

Method for producing catalysis from coal  

DOE Patents [OSTI]

A method for producing catalysts from coal is provided comprising mixing an aqueous alkali solution with the coal, heating the aqueous mixture to treat the coal, drying the now-heated aqueous mixture, reheating the mixture to form carbonized material, cooling the mixture, removing excess alkali from the carbonized material, and recovering the carbonized material, wherein the entire process is carried out in controlled atmospheres, and the carbonized material is a hydrocracking or hydrodehalogenation catalyst for liquid phase reactions. The invention also provides for a one-step method for producing catalysts from coal comprising mixing an aqueous alkali solution with the coal to create a mixture, heating the aqueous mixture from an ambient temperature to a predetermined temperature at a predetermined rate, cooling the mixture, and washing the mixture to remove excess alkali from the treated and carbonized material, wherein the entire process is carried out in a controlled atmosphere.

Farcasiu, Malvina (Pittsburgh, PA); Derbyshire, Frank (Lexington, KY); Kaufman, Phillip B. (Library, PA); Jagtoyen, Marit (Lexington, KY)

1998-01-01T23:59:59.000Z

404

Method for producing catalysts from coal  

DOE Patents [OSTI]

A method for producing catalysts from coal is provided comprising mixing an aqueous alkali solution with the coal, heating the aqueous mixture to treat the coal, drying the now-heated aqueous mixture, reheating the mixture to form carbonized material, cooling the mixture, removing excess alkali from the carbonized material, and recovering the carbonized material, wherein the entire process is carried out in controlled atmospheres, and the carbonized material is a hydrocracking or hydrodehalogenation catalyst for liquid phase reactions. The invention also provides for a one-step method for producing catalysts from coal comprising mixing an aqueous alkali solution with the coal to create a mixture, heating the aqueous mixture from an ambient temperature to a predetermined temperature at a predetermined rate, cooling the mixture, and washing the mixture to remove excess alkali from the treated and carbonized material, wherein the entire process is carried out in a controlled atmosphere. 1 fig.

Farcasiu, M.; Derbyshire, F.; Kaufman, P.B.; Jagtoyen, M.

1998-02-24T23:59:59.000Z

405

Method for producing highly reflective metal surfaces  

DOE Patents [OSTI]

The invention is a novel method for producing mirror surfaces which are extremely smooth and which have high optical reflectivity. The method includes depositing, by electrolysis, an amorphous layer of nickel on an article and then diamond-machining the resulting nickel surface to increase its smoothness and reflectivity. The machined nickel surface then is passivated with respect to the formation of bonds with electrodeposited nickel. Nickel then is electrodeposited on the passivated surface to form a layer of electroplated nickel whose inside surface is a replica of the passivated surface. The mandrel then may be-re-passivated and provided with a layer of electrodeposited nickel, which is then recovered from the mandrel providing a second replica. The mandrel can be so re-used to provide many such replicas. As compared with producing each mirror-finished article by plating and diamond-machining, the new method is faster and less expensive.

Arnold, J.B.; Steger, P.J.; Wright, R.R.

1982-03-04T23:59:59.000Z

406

Producing and Marketing High-Value Calves  

E-Print Network [OSTI]

carcasses. Oklahoma State University (Smith et al., 2000) and University of Arkansas (Troxel et al., 2001) researchers conducted livestock market surveys to determine factors that affect value in feeder cattle. Their data indicate that small... cattle that will produce calves with adequate muscling. Body condition. The Oklahoma study found that thin cattle received discounts of $9 to $10 per cwt when compared to cattle of average condition, and that fat cattle received discounts of $6...

Cleere, Jason; Boleman, Larry L.

2006-06-22T23:59:59.000Z

407

Adventures in Laser Produced Plasma Research  

SciTech Connect (OSTI)

In the UK the study of laser produced plasmas and their applications began in the universities and evolved to a current system where the research is mainly carried out at the Rutherford Appleton Laboratory Central Laser Facility ( CLF) which is provided to support the universities. My own research work has been closely tied to this evolution and in this review I describe the history with particular reference to my participation in it.

Key, M

2006-01-13T23:59:59.000Z

408

Process for producing furan from furfural aldehyde  

DOE Patents [OSTI]

A process of producing furan and derivatives thereof as disclosed. The process includes generating furfural aldehyde vapors and then passing those vapors over a zeolite catalyst at a temperature and for a residence time effective to decarbonylate the furfural aldehydes to form furans and derivatives thereof. The resultant furan vapors and derivatives are then separated. In a preferred form, the furfural aldehyde vapors are generated during the process of converting biomass materials to liquid and gaseous fuels.

Diebold, J.P.; Evans, R.J.

1987-04-06T23:59:59.000Z

409

Effects of additive C{sub 4}F{sub 8} during inductively coupled BCl{sub 3}/C{sub 4}F{sub 8}/Ar plasma etching of TaN and HfO{sub 2} for gate stack patterning  

SciTech Connect (OSTI)

In this work, the authors investigated the etching characteristics of TaN and HfO{sub 2} layers for gate stack patterning in BCl{sub 3}/Ar and BCl{sub 3}/C{sub 4}F{sub 8}/Ar inductively coupled plasmas and the effects of C{sub 4}F{sub 8} addition on the etch selectivity of the TaN to the HfO{sub 2} layer. Addition of C{sub 4}F{sub 8} gas to the BCl{sub 3}/Ar chemistry improved the TaN/HfO{sub 2} etch selectivity because adding the C{sub 4}F{sub 8} gas enhances the formation of the CF{sub x}Cl{sub y} passivation layer on HfO{sub 2} surface and decreased the HfO{sub 2} etch rate more rapidly than the TaN etch rate in a disproportionate way. Reduction in the etch time for HfO{sub 2} layer also increases the TaN/HfO{sub 2} etch selectivity because the etch time gets closer to the initiation time for HfO{sub 2} etching.

Ko, J. H.; Kim, D. Y.; Park, M. S.; Lee, N.-E.; Lee, S. S.; Ahn, Jinho; Mok, Hyungsoo [School of Advanced Materials Science and Engineering, and Center for Advanced Plasma Surface Technology, Sungkyunkwan University, Suwon, Kyunggi-do 440-746 (Korea, Republic of); Division of Advanced Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Department of Electrical Engineering, Konkuk University, 1 Hwayangdong, Gwangjingu, Seoul 143-701 (Korea, Republic of)

2007-07-15T23:59:59.000Z

410

Selective etching of high-k HfO{sub 2} films over Si in hydrogen-added fluorocarbon (CF{sub 4}/Ar/H{sub 2} and C{sub 4}F{sub 8}/Ar/H{sub 2}) plasmas  

SciTech Connect (OSTI)

Inductively coupled hydrogen-added fluorocarbon (CF{sub 4}/Ar/H{sub 2} and C{sub 4}F{sub 8}/Ar/H{sub 2}) plasmas were used to etch HfO{sub 2}, which is a promising high-dielectric-constant material for the gate of complementary metal-oxide-semiconductor devices. The etch rates of HfO{sub 2} and Si were drastically changed depending on the additive-H{sub 2} flow rate in C{sub 4}F{sub 8}/Ar/H{sub 2} plasmas. The highly selective etching of HfO{sub 2} over Si was done in the condition with an additive-H{sub 2} flow rate, where the Si surface was covered with the fluorocarbon polymer. The results of x-ray photoelectron spectroscopy indicated that the carbon content of the selectively etched HfO{sub 2} surface was extremely low compared with the preetched surface contaminated by adventitious hydrocarbon in atmosphere. In the gas phase of the C{sub 4}F{sub 8}/Ar/H{sub 2} plasmas, Hf hydrocarbide molecules such as metal-organic compounds and Hf hydrofluoride were detected by a quadrupole mass analyzer. These findings indicate that the fluorine species, carbon, and hydrogen can work to etch HfO{sub 2} and that the carbon species also plays an important role in selective etching of HfO{sub 2} over Si.

Takahashi, Kazuo; Ono, Kouichi [Department of Aeronautics and Astronautics, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)

2006-05-15T23:59:59.000Z

411

Glass produced by underground nuclear explosions. [Rainier  

SciTech Connect (OSTI)

Detonation of an underground nuclear explosive produces a strong shock wave which propagates spherically outward, vaporizing the explosive and nearby rock and melting, the surrounding rock. The vaporized material expands adiabatically, forming a cavity. As the energy is dissipated during the cavity formation process, the explosive and rock debris condense and mix with the melted rock. The melt flows to the bottom of the cavity where it is quenched by fractured rock fragments falling from above as the cavity collapses. Measurements indicate that about 740 tonnes of rock and/or soil are melted for every kiloton (10/sup 12/ calories) of explosive energy, or about 25% of the explosive energy goes to melting rock. The resulting glass composition reflects the composition of the unaltered rock with explosive debris. The appearance ranges from white pumice to dense, dark lava. The bulk composition and color vary with the amount of explosive iron incorporated into the glass. The refractory explosion products are mixed with the solidified melt, although the degree of mixing is variable. Electron microprobe studies of glasses produced by Rainier in welded tuff have produced the following results: glasses are dehydrated relative to the host media, glasses are extremely heterogeneous on a 20 ..mu..m scale, a ubiquitous feature is the presence of dark marble-cake regions in the glass, which were locally enriched in iron and may be related to the debris, optically amorphous regions provide evidence of shock melting, only limited major element redistribution and homogenization occur within the cavity.

Schwartz, L.; Piwinskii, A.; Ryerson, F.; Tewes, H.; Beiriger, W.

1983-01-01T23:59:59.000Z

412

Beneficial Reuse of San Ardo Produced Water  

SciTech Connect (OSTI)

This report summarizes the work performed from 1 April 2003 to 30 September 2003 and recommends the tasks to be performed during Phase II (Pilot Evaluation). During this period discussions were held with various water agencies regarding use of the treated produced water either directly or indirectly through a water trading arrangement. In particular, several discussions were held with Monterey County Water Resources Agency, that has been charged with the long-term management and preservation of water resources in Monterey County. The Agency is very supportive of the program. However, they would like to see water quality/cost estimate data for the treated produced water from the pilot study prior to evaluating water use/water trade options. The agency sent a letter encouraging the project team to perform the pilot study to evaluate feasibility of the project. In addition, the regulations related to use of the treated water for various applications were updated during this period. Finally, the work plan, health and safety plan and sample analyses plan for performing pilot study to treat the oilfield produced water were developed during this period.

Robert A. Liske

2003-09-26T23:59:59.000Z

413

Collapse of ferromagnetism in itinerant-electron system: A magnetic, transport properties, and high pressure study of (Hf,Ta)Fe{sub 2} compounds  

SciTech Connect (OSTI)

The magnetism and transport properties were studied for Laves (Hf,Ta)Fe{sub 2} itinerant-electron compounds, which exhibit a temperature-induced first-order transition from the ferromagnetic (FM) to the antiferromagnetic (AFM) state upon heating. At finite temperatures, the field-induced metamagnetic phase transition between the AFM and FM has considerable effects on the transport properties of these model metamagnetic compounds. A large negative magnetoresistance of about 14% is observed in accordance with the metamagnetic transition. The magnetic phase diagram is determined for the Laves Hf{sub 1?x}Ta{sub x}Fe{sub 2} series and its Ta concentration dependence discussed. An unusual behavior is revealed in the paramagnetic state of intermediate compositions, it gives rise to the rapid increase and saturation of the local spin fluctuations of the 3d electrons. This new result is analysed in the frame of the theory of Moriya. For a chosen composition Hf{sub 0.825}Ta{sub 0.175}Fe{sub 2}, exhibiting such remarkable features, a detailed investigation is carried out under hydrostatic pressure up to 1?GPa in order to investigate the volume effect on the magnetic properties. With increasing pressure, the magnetic transition temperature T{sub FM-AFM} from ferromagnetic to antiferromagnetic order decreases strongly non-linearly and disappears at a critical pressure of 0.75?GPa. In the pressure-induced AFM state, the field-induced first-order AFM-FM transition appears and the complex temperature dependence of the AFM-FM transition field is explained by the contribution from both the magnetic and elastic energies caused by the significant temperature variation of the amplitude of the local Fe magnetic moment. The application of an external pressure leads also to the progressive decrease of the Néel temperature T{sub N}. In addition, a large pressure effect on the spontaneous magnetization M{sub S} for pressures below 0.45?GPa, dln(M{sub s})/dP?=??6.3?×?10{sup ?2?}GPa{sup ?1} was discovered. The presented results are consistent with Moriya's theoretical predictions and can significantly help to better understand the underlying physics of itinerant electron magnetic systems nowadays widely investigated for both fundamental and applications purposes.

Diop, L. V. B., E-mail: leopold.diop@neel.cnrs.fr; Isnard, O. [Univ. Grenoble Alpes, Inst NEEL, F-38042 Grenoble (France); CNRS, Inst NEEL, F-38042 Grenoble (France); Kastil, J. [Univ. Grenoble Alpes, Inst NEEL, F-38042 Grenoble (France); CNRS, Inst NEEL, F-38042 Grenoble (France); Institute of Physics AS CR v.v.i., Na Slovance 2, 182 21 Prague 8 (Czech Republic); Arnold, Z.; Kamarad, J. [Institute of Physics AS CR v.v.i., Na Slovance 2, 182 21 Prague 8 (Czech Republic)

2014-10-28T23:59:59.000Z

414

TUNGSTEN ISOTOPIC COMPOSITIONS IN STARDUST SiC GRAINS FROM THE MURCHISON METEORITE: CONSTRAINTS ON THE s-PROCESS IN THE Hf-Ta-W-Re-Os REGION  

SciTech Connect (OSTI)

We report the first tungsten isotopic measurements in stardust silicon carbide (SiC) grains recovered from the Murchison carbonaceous chondrite. The isotopes {sup 182,183,184,186}W and {sup 179,180}Hf were measured on both an aggregate (KJB fraction) and single stardust SiC grains (LS+LU fraction) believed to have condensed in the outflows of low-mass carbon-rich asymptotic giant branch (AGB) stars with close-to-solar metallicity. The SiC aggregate shows small deviations from terrestrial (= solar) composition in the {sup 182}W/{sup 184}W and {sup 183}W/{sup 184}W ratios, with deficits in {sup 182}W and {sup 183}W with respect to {sup 184}W. The {sup 186}W/{sup 184}W ratio, however, shows no apparent deviation from the solar value. Tungsten isotopic measurements in single mainstream stardust SiC grains revealed lower than solar {sup 182}W/{sup 184}W, {sup 183}W/{sup 184}W, and {sup 186}W/{sup 184}W ratios. We have compared the SiC data with theoretical predictions of the evolution of W isotopic ratios in the envelopes of AGB stars. These ratios are affected by the slow neutron-capture process and match the SiC data regarding their {sup 182}W/{sup 184}W, {sup 183}W/{sup 184}W, and {sup 179}Hf/{sup 180}Hf isotopic compositions, although a small adjustment in the s-process production of {sup 183}W is needed in order to have a better agreement between the SiC data and model predictions. The models cannot explain the {sup 186}W/{sup 184}W ratios observed in the SiC grains, even when the current {sup 185}W neutron-capture cross section is increased by a factor of two. Further study is required to better assess how model uncertainties (e.g., the formation of the {sup 13}C neutron source, the mass-loss law, the modeling of the third dredge-up, and the efficiency of the {sup 22}Ne neutron source) may affect current s-process predictions.

Avila, Janaina N.; Ireland, Trevor R.; Holden, Peter [Research School of Earth Sciences, Australian National University, Canberra, ACT 0200 (Australia); Lugaro, Maria; Buntain, Joelene [Centre for Stellar and Planetary Astrophysics, Monash University, Clayton, VIC 3800 (Australia); Gyngard, Frank; Zinner, Ernst; Amari, Sachiko [Laboratory for Space Sciences and the Department of Physics, Washington University, One Brookings Drive, St. Louis, MO 63130 (United States); Cristallo, Sergio [Departamento de Fisica Teorica y del Cosmos, Universidad de Granada, Granada 18071 (Spain); Karakas, Amanda, E-mail: janaina.avila@anu.edu.au [Mount Stromlo Observatory, Australian National University, Weston Creek, ACT 2611 (Australia)

2012-01-01T23:59:59.000Z

415

Method of producing a cellulase-containing cell-free fermentate produced from microorganism ATCC 55702  

DOE Patents [OSTI]

Bacteria which produce large amounts of cellulose-containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques. 5 figs.

Dees, H.C.

1998-05-26T23:59:59.000Z

416

Method of producing a cellulase-containing cell-free fermentate produced from microorganism ATCC 55702  

DOE Patents [OSTI]

Bacteria which produce large amounts of cellulose-containing cell-free fermentate have been identified. The original bacterium (ATCC 55703) was genetically altered using nitrosoguanidine (MNNG) treatment to produce the enhanced cellulase producing bacterium (ATCC 55702), which was identified through replicate plating. ATCC 55702 has improved characteristics and qualities for the degradation of cellulosic waste materials for fuel production, food processing, textile processing, and other industrial applications. ATCC 55702 is an improved bacterial host for genetic manipulations using recombinant DNA techniques, and is less likely to destroy genetic manipulations using standard mutagenesis techniques.

Dees, H. Craig (Lenoir City, TN)

1998-01-01T23:59:59.000Z

417

Method of producing .beta.-spodumene bodies  

DOE Patents [OSTI]

Beta-spodumene bodies and method of preparing the bodies that involves providing a uniform plastic batch of inorganic raw materials, organic binder, and vehicle, wherein the inorganic raw materials are composed of, in percent by weight, about 75% to 95% minerals, and about 5% to 25% glass. The batch is formed into a green body that is fired to produce a body composed substantially of beta-spodumene, and having a thermal expansion coefficient of <10.times.10.sup.-7 /.degree.C.(0-800.degree. C.), and a strength of .gtoreq.4 Ksi.

Chyung, Kenneth (Painted Post, NY); Day, J. Paul (Big Flats, NY); Holleran, Louis M. (Big Flats, NY); Olszewski, Anthony R. (Bath, NY)

1999-01-01T23:59:59.000Z

418

Process for producing phenolic compounds from lignins  

DOE Patents [OSTI]

A process is described for the production of low molecular weight phenolic compounds from lignins through the pyrolysis of the lignins in the presence of a strong base. In a preferred embodiment, potassium hydroxide is present in an amount of from about 0.1% to about 5% by weight, the pyrolysis temperature is from about 400 C to about 600 C at atmospheric pressure, and the time period for substantial completion of the reaction is from about 1--3 minutes. Examples of low molecular weight phenolic compounds produced include methoxyphenols, non-methoxylated phenols, and mixtures thereof. 16 figs.

Agblevor, F.A.

1998-09-15T23:59:59.000Z

419

High ethanol producing derivatives of Thermoanaerobacter ethanolicus  

DOE Patents [OSTI]

Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).

Ljungdahl, L.G.; Carriera, L.H.

1983-05-24T23:59:59.000Z

420

High ethanol producing derivatives of Thermoanaerobacter ethanolicus  

DOE Patents [OSTI]

Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).

Ljungdahl, Lars G. (Athens, GA); Carriera, Laura H. (Athens, GA)

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Carbene reactions produced by recoil excitation methods  

E-Print Network [OSTI]

CARBENE REACTIONS PRODDCED BY RECOIL EXCITATION METHODS A Thesis by Kirby Lowery, Jr. Submitted to the Graduate College of Texas ASM University in Partial fulfillment of the requirements for the oeSree of PjASTER Or SCIENCE Auyust (month...) Ma&or Subject 1968 (year) Che !is try CARBENE REACTIONS PRODUCED BY RECOIL EXCITATION METHODS A Thesis by Kirby Lowery, Jr. Approved as to style and content by: (Head of Department) (Memb er ) (iMember ) (Member) (iM err:b e r ) (Member...

Lowery, Kirby

1968-01-01T23:59:59.000Z

422

Method for producing metal oxide nanoparticles  

DOE Patents [OSTI]

Method for producing metal oxide nanoparticles. The method includes generating an aerosol of solid metallic microparticles, generating plasma with a plasma hot zone at a temperature sufficiently high to vaporize the microparticles into metal vapor, and directing the aerosol into the hot zone of the plasma. The microparticles vaporize in the hot zone into metal vapor. The metal vapor is directed away from the hot zone and into the cooler plasma afterglow where it oxidizes, cools and condenses to form solid metal oxide nanoparticles.

Phillips, Jonathan (Santa Fe, NM); Mendoza, Daniel (Santa Fe, NM); Chen, Chun-Ku (Albuquerque, NM)

2008-04-15T23:59:59.000Z

423

Clean Energy Producing and Exporting Countries  

E-Print Network [OSTI]

Abstract KOUROS ATIGHETCHI BSc, MBA,PhD Student School of Business and Management , Brunel University, Uxbridge, Middlesex UB8 3PH, UK atighetchi@gmail.com This paper presents a theoretical discussion of policy making in the energy... with it implications. ESL-IE-07-05-29 Proceedings from the Twenty-ninth Industrial Energy Technology Conference, New Orleans, LA, May 8-11, 2007. Finally, this model will be presented to various Natural Gas producing countries such as Iran, Iraq, Russia, and Saudi...

Atighetchi, K.

2007-01-01T23:59:59.000Z

424

Performance profiles of major energy producers 1994  

SciTech Connect (OSTI)

Performance Profiles of Major Energy Producers 1994 is the eighteenth annual report of the Energy Information Administration`s (EIA) Financial Reporting System (FRS). The report examines financial and operating developments in energy markets, with particular reference to the 24 major U.S. energy companies required to report annually on Form EIA-28. Financial information is reported by major lines of business, including oil and gas production, petroleum refining and marketing, other energy operations, and nonenergy businesses. Financial and operating results are presented in the context of energy market developments with a view toward identifying changing corporate strategies and measuring the performance of ongoing operations both in the United States and abroad.

NONE

1996-02-01T23:59:59.000Z

425

Method of producing particulate-reinforced composites and composties produced thereby  

DOE Patents [OSTI]

A process for producing particle-reinforced composite materials through utilization of an in situ reaction to produce a uniform dispersion of a fine particulate reinforcement phase. The process includes forming a melt of a first material, and then introducing particles of a second material into the melt and subjecting the melt to high-intenisty acoustic vibration. A chemical reaction initiates between the first and second materials to produce reaction products in the melt. The reaciton products comprise a solide particulate phase, and the high-intensity acoustic vibration fragments and/or separates the reaction products into solid particles that are dispersed in the melt and are smaller than the particles of the second material. Also encompassed are particles-reinforced composite materials produced by such a process.

Han, Qingyou; Liu, Zhiwei

2013-12-24T23:59:59.000Z

426

Comparison of the vacuum-ultraviolet radiation response of HfO{sub 2}/SiO{sub 2}/Si dielectric stacks with SiO{sub 2}/Si  

SciTech Connect (OSTI)

Vacuum ultraviolet (vuv) emitted during plasma processing degrades dielectrics by generating electron-hole pairs. VUV-induced charging of SiO{sub 2}/p-Si and HfO{sub 2}/SiO{sub 2}/p-Si dielectric stacks are compared. For SiO{sub 2}/p-Si, charging is observed for photon energies >15 eV by ionization of dielectric atoms from photoinjected electrons. In HfO{sub 2}/SiO{sub 2}/p-Si, charging is observed for photon >10 eV and is due to ionization by photoinjected electrons and by H{sup +} trapping in the HfO{sub 2}/SiO{sub 2} bulk. Hydrogen appears during annealing at the Si-SiO{sub 2} interface forming Si-H, which, during irradiation, is depassivated by photoinjected electrons. The authors conclude that dielectric charging in thin oxides (<10 nm) occurs more easily in HfO{sub 2}/SiO{sub 2} than in SiO{sub 2}.

Upadhyaya, G. S.; Shohet, J. L. [Plasma Processing and Technology Laboratory, and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2007-02-12T23:59:59.000Z

427

In-operando hard X-ray photoelectron spectroscopy study on the impact of current compliance and switching cycles on oxygen and carbon defects in resistive switching Ti/HfO{sub 2}/TiN cells  

SciTech Connect (OSTI)

In this study, direct experimental materials science evidence of the important theoretical prediction for resistive random access memory (RRAM) technologies that a critical amount of oxygen vacancies is needed to establish stable resistive switching in metal-oxide-metal samples is presented. In detail, a novel in-operando hard X-ray photoelectron spectroscopy technique is applied to non-destructively investigates the influence of the current compliance and direct current voltage sweep cycles on the Ti/HfO{sub 2} interface chemistry and physics of resistive switching Ti/HfO{sub 2}/TiN cells. These studies indeed confirm that current compliance is a critical parameter to control the amount of oxygen vacancies in the conducting filaments in the oxide layer during the RRAM cell operation to achieve stable switching. Furthermore, clear carbon segregation towards the Ti/HfO{sub 2} interface under electrical stress is visible. Since carbon impurities impact the oxygen vacancy defect population under resistive switching, this dynamic carbon segregation to the Ti/HfO{sub 2} interface is suspected to negatively influence RRAM device endurance. Therefore, these results indicate that the RRAM materials engineering needs to include all impurities in the dielectric layer in order to achieve reliable device performance.

Sowinska, Malgorzata, E-mail: sowinska@ihp-microelectronics.com; Bertaud, Thomas; Walczyk, Damian; Calka, Pauline; Walczyk, Christian [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Thiess, Sebastian [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg (Germany); Alff, Lambert [Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt (Germany); Schroeder, Thomas [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Brandenburgische Technische Universität, Konrad-Zuse-Strasse 1, 03046 Cottbus (Germany)

2014-05-28T23:59:59.000Z

428

Effects of N{sub 2} remote plasma nitridation on the structural and electrical characteristics of the HfO{sub 2} gate dielectrics grown using remote plasma atomic layer deposition methods  

SciTech Connect (OSTI)

The characteristics of remote plasma atomic layer deposited HfO{sub 2} on Si, which has a very thin SiO{sub 2} interlayer with and without remote plasma nitridation (RPN), have been investigated. Small amounts of N atoms were successfully incorporated by RPN pretreatment, in which the dominant emission species were excited atomic nitrogen (N{sup *}) and excited molecular nitrogen (N{sub 2}{sup *}), into a very thin SiO{sub 2} interlayer for the growth of HfO{sub 2} thin film. The thin ({approx}1.5 nm) intermediate layer containing nitrogen, which was prepared by sequential O{sub 2} and N{sub 2} remote plasma treatment of the Si substrate, can effectively suppress growth of the unintentional interface layer. In addition, it enhances the thermal stability and the resistance to oxygen diffusion during rapid thermal annealing. The HfO{sub 2} film containing the remote plasma nitrided SiO{sub 2} interlayer annealed at 800 deg. C showed a lower equivalent oxide thickness of {approx}1.89 nm and a lower leakage current density (3.78x10{sup -7} A cm{sup -2} at |V{sub G}-V{sub FB}|=2 V) compared to a non-nitrided sample of the same physical thickness. Also, we compared the characteristics of HfO{sub 2} films annealed in two different ambient environments, N{sub 2} and O{sub 2}.

Choi, Jihoon; Kim, Seokhoon; Kim, Jinwoo; Kang, Hyunseok; Jeon, Hyeongtag; Bae, Choelhwyi [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States)

2006-07-15T23:59:59.000Z

429

Analysis of trap state densities at HfO{sub 2}/In{sub 0.53}Ga{sub 0.47}As interfaces  

SciTech Connect (OSTI)

HfO{sub 2} was deposited on n- and p-type In{sub 0.53}Ga{sub 0.47}As by chemical beam deposition. Interface trap densities (D{sub it}) and their energy level distribution were quantified using the conductance method in a wide temperature range (77 to 300 K). A trap level close to the intrinsic energy level caused the D{sub it} to rise above 10{sup 13} cm{sup -2} eV{sup -1}. The trap level at midgap gives rise to false inversion behavior in the capacitance-voltage curves for n-type channels at room temperature. The apparent decrease of the D{sub it} close to the band edges is discussed.

Hwang, Yoontae; Engel-Herbert, Roman; Rudawski, Nicholas G.; Stemmer, Susanne [Materials Department, University of California, Santa Barbara, California 93106-5050 (United States)

2010-03-08T23:59:59.000Z

430

Film properties of low temperature HfO{sub 2} grown with H{sub 2}O, O{sub 3}, or remote O{sub 2}-plasma  

SciTech Connect (OSTI)

A reduction of the deposition temperature is necessary for atomic layer deposition (ALD) on organic devices. HfO{sub 2} films were deposited by ALD on silicon substrates in a wide temperature range from 80 to 300?°C with tetrakis[ethylmethylamino]hafnium as metal precursor and H{sub 2}O, O{sub 3}, or an remote O{sub 2}-plasma as oxygen source. Growth rate and density were correlated to electrical properties like dielectric constant and leakage current of simple capacitor structures to evaluate the impact of different process conditions. Process optimizations were performed to reduce film imperfections visible at lower deposition temperatures. Additionally, the influence of postdeposition annealing on the structural and electrical properties was studied.

Richter, Claudia, E-mail: Claudia.Richter@namlab.com; Schenk, Tony; Schroeder, Uwe [NaMLab gGmbH, Noethnitzerstr. 64, 01187 Dresden (Germany); Mikolajick, Thomas [NaMLab gGmbH, Noethnitzerstr. 64, 01187 Dresden, Germany and Institut für Halbleiter und Mikrosystemtechnik, TU Dresden, Noethnitzerstr. 64, 01187 Dresden (Germany)

2014-01-15T23:59:59.000Z

431

Reduction of native oxides on InAs by atomic layer deposited Al{sub 2}O{sub 3} and HfO{sub 2}  

SciTech Connect (OSTI)

Thin high-{kappa} oxide films on InAs, formed by atomic layer deposition, are the key to achieve high-speed metal-oxide-semiconductor devices. We have studied the native oxide and the interface between InAs and 2 nm thick Al{sub 2}O{sub 3} or HfO{sub 2} layers using synchrotron x-ray photoemission spectroscopy. Both films lead to a strong oxide reduction, obtaining less than 10% of the native As-oxides and between 10% and 50% of the native In-oxides, depending on the deposition temperature. The ratio of native In- to As-oxides is determined to be 2:1. The exact composition and the influence of different oxidation states and suboxides is discussed in detail.

Timm, R.; Fian, A.; Hjort, M.; Thelander, C.; Lind, E.; Andersen, J. N.; Wernersson, L.-E.; Mikkelsen, A. [Department of Physics, Nanometer Structure Consortium, Lund University, P.O. Box 118, 22 100 Lund (Sweden)

2010-09-27T23:59:59.000Z

432

Surface and interfacial reaction study of half cycle atomic layer deposited HfO{sub 2} on chemically treated GaSb surfaces  

SciTech Connect (OSTI)

An in situ half-cycle atomic layer deposition/X-ray photoelectron spectroscopy (XPS) study was conducted in order to investigate the evolution of the HfO{sub 2} dielectric interface with GaSb(100) surfaces after sulfur passivation and HCl etching, designed to remove the native oxides. With the first pulses of tetrakis(dimethylamido)hafnium(IV) and water, a decrease in the concentration of antimony oxide states present on the HCl-etched surface is observed, while antimony sulfur states diminished below the XPS detection limit on sulfur passivated surface. An increase in the amount of gallium oxide/sulfide is seen, suggesting oxygen or sulfur transfers from antimony to gallium during antimony oxides/sulfides decomposition.

Zhernokletov, D. M. [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States)] [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States); Dong, H.; Brennan, B.; Kim, J. [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States)] [Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States); Yakimov, M.; Tokranov, V.; Oktyabrsky, S. [College of Nanoscale Science and Engineering, University at Albany - SUNY, Albany, New York 12203 (United States)] [College of Nanoscale Science and Engineering, University at Albany - SUNY, Albany, New York 12203 (United States); Wallace, R. M. [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States) [Department of Physics, University of Texas at Dallas, Richardson, Texas 75080 (United States); Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas 75080 (United States)

2013-04-01T23:59:59.000Z

433

Laser damage study of nodules in electron-beam-evaporated HfO{sub 2}/SiO{sub 2} high reflectors  

SciTech Connect (OSTI)

A reactive electron beam evaporation process was used to fabricate 1.064 {mu}mHfO{sub 2}/SiO{sub 2} high reflectors. The deposition process was optimized to reduce the nodular density. Cross-sectioning of nodular defects by a focused ion-beam milling instrument showed that the nodule seeds were the residual particles on the substrate and the particulates from the silica source ''splitting.'' After optimizing the substrate preparation procedure and the evaporation process, a low nodular density of 2.7/mm{sup 2} was achieved. The laser damage test revealed that the ejection fluences and damage growth behaviors of nodules created from deep or shallow seeds were totally different. A mechanism based on directional plasma scald was proposed to interpret observed damage growth phenomenon.

Cheng Xinbin; Shen Zhengxiang; Jiao Hongfei; Zhang Jinlong; Ma Bin; Ding Tao; Lu Jiangtao; Wang Xiaodong; Wang Zhanshan

2011-03-20T23:59:59.000Z

434

Trip Report-Produced-Water Field Testing  

SciTech Connect (OSTI)

Los Alamos National Laboratory (LANL) conducted field testing of a produced-water pretreatment apparatus with assistance from faculty at the Texas A&M University (TAMU) protein separation sciences laboratory located on the TAMU main campus. The following report details all of the logistics surrounding the testing. The purpose of the test was to use a new, commercially-available filter media housing containing modified zeolite (surfactant-modified zeolite or SMZ) porous medium for use in pretreatment of oil and gas produced water (PW) and frac-flowback waters. The SMZ was tested previously in October, 2010 in a lab-constructed configuration ('old multicolumn system'), and performed well for removal of benzene, toluene, ethylbenzene, and xylenes (BTEX) from PW. However, a less-expensive, modular configuration is needed for field use. A modular system will allow the field operator to add or subtract SMZ filters as needed to accommodate site specific conditions, and to swap out used filters easily in a multi-unit system. This test demonstrated the use of a commercial filter housing with a simple flow modification and packed with SMZ for removing BTEX from a PW source in College Station, Texas. The system will be tested in June 2012 at a field site in Pennsylvania for treating frac-flowback waters. The goals of this test are: (1) to determine sorption efficiency of BTEX in the new configuration; and (2) to observe the range of flow rates, backpressures, and total volume treated at a given flow rate.

Sullivan, Enid J. [Los Alamos National Laboratory

2012-05-25T23:59:59.000Z

435

Method for producing and treating coal gases  

DOE Patents [OSTI]

A method of generating a de-sulphurized volatile matter and a relatively low Btu gas includes the initial step of pyrolyzing coal to produce volatile matter and a char. The volatile matter is fed to a first de-sulphurizer containing a de-sulphurizing agent to remove sulphur therefrom. At the same time, the char is gasified to produce a relatively low Btu gas. The low Btu gas is fed to a second de-sulphurizer containing the de-sulphurizing agent to remove sulphur therefrom. A regenerator is provided for removing sulphur from the de-sulphurizing agent. Portions of the de-sulphurizing agent are moved among the first de-sulphurizer, the second de-sulphurizer, and the regenerator such that the regenerator regenerates the de-sulphurizing agent. Preferably, the portions of the de-sulphurizing agent are moved from the second de-sulphurizer to the first de-sulphurizer, from the first de-sulphurizer to the regenerator, and from the regenerator to the second de-sulphurizer.

Calderon, Albert (P.O. Box 126, Bowling Green, OH 43402)

1990-01-01T23:59:59.000Z

436

Co-sputtering yttrium into hafnium oxide thin films to produce ferroelectric properties  

SciTech Connect (OSTI)

Thin film capacitors were fabricated by sputtering TiN-Y doped HfO{sub 2}-TiN stacks on silicon substrates. Yttrium was incorporated into the HfO{sub 2} layers by simultaneously sputtering from Y{sub 2}O{sub 3} and HfO{sub 2} sources. Electric polarization and relative permittivity measurements yield distinct ferroelectric properties as a result of low yttrium dopant concentrations in the range of 0.9-1.9 mol. %. Grazing incidence x-ray diffraction measurements show the formation of an orthorhombic phase in this range. Compared to atomic layer deposition films, the highest remanent polarization and the highest relative permittivity were obtained at significantly lower doping concentrations in these sputtered films.

Olsen, T. [NaMLab gGmbH, 01187 Dresden (Germany); Department of Electrical and Computer Engineering, University of Alberta, Edmonton T6G 2V4 (Canada); Schroeder, U.; Mueller, S.; Krause, A.; Martin, D.; Singh, A. [NaMLab gGmbH, 01187 Dresden (Germany); Mueller, J. [Fraunhofer CNT, 01099 Dresden (Germany); Geidel, M. [Institute of Semiconductors and Microsystems, Technische Universitaet Dresden, 01062 Dresden (Germany); Mikolajick, T. [NaMLab gGmbH, 01187 Dresden (Germany); Institute of Semiconductors and Microsystems, Technische Universitaet Dresden, 01062 Dresden (Germany)

2012-08-20T23:59:59.000Z

437

Rocky Mountain Basins Produced Water Database  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

Historical records for produced water data were collected from multiple sources, including Amoco, British Petroleum, Anadarko Petroleum Corporation, United States Geological Survey (USGS), Wyoming Oil and Gas Commission (WOGC), Denver Earth Resources Library (DERL), Bill Barrett Corporation, Stone Energy, and other operators. In addition, 86 new samples were collected during the summers of 2003 and 2004 from the following areas: Waltman-Cave Gulch, Pinedale, Tablerock and Wild Rose. Samples were tested for standard seven component "Stiff analyses", and strontium and oxygen isotopes. 16,035 analyses were winnowed to 8028 unique records for 3276 wells after a data screening process was completed. [Copied from the Readme document in the zipped file available at http://www.netl.doe.gov/technologies/oil-gas/Software/database.html] Save the Zipped file to your PC. When opened, it will contain four versions of the database: ACCESS, EXCEL, DBF, and CSV formats. The information consists of detailed water analyses from basins in the Rocky Mountain region.

438

Performance profiles of major energy producers 1992  

SciTech Connect (OSTI)

Performance Profiles of Major Energy Producers 1992 is the sixteenth annual report of the Energy Information Administration`s (EIA) Financial Reporting System (FRS). The report examines financial and operating developments, with particular reference to the 25 major energy companies (the FRS companies) required to report annually on Form EIA-28. Financial information is reported by major lines of business, including oil and gas production, petroleum refining and marketing, and other energy operations. Domestic and international operations are examined separately in this report. The data are presented in the context of key energy market developments with a view toward identifying changing strategies of corporate development and measuring the apparent success of current ongoing operations.

Not Available

1994-01-13T23:59:59.000Z

439

Performance profiles of major energy producers 1993  

SciTech Connect (OSTI)

Performance Profiles of Major Energy Producers 1993 is the seventeenth annual report of the Energy Information Administration`s (EIA) Financial Reporting System (FRS). The report examines financial and operating developments in energy markets, with particular reference to the 25 major US energy companies required to report annually on Form EIA-28. Financial information is reported by major liens of business, including oil and gas production, petroleum refining and marketing, other energy operations, and nonenergy businesses. Financial and operating results are presented in the context of energy market developments with a view toward identifying changing corporate strategies and measuring the performance of ongoing operations both in the US and abroad. This year`s report analyzes financial and operating developments for 1993 (Part 1: Developments in 1993) and also reviews key developments during the 20 years following the Arab Oil Embargo of 1973--1974 (Part 2: Major Energy Company Strategies Since the Arab Oil Embargo). 49 figs., 104 tabs.

NONE

1995-01-01T23:59:59.000Z

440

Performance profiles of major energy producers 1996  

SciTech Connect (OSTI)

This publication examines developments in the operations of the major US e energy-producing companies on a corporate level, by major line of business, by major function within each line of business, and by geographic area. In 1996, 24 companies filed Form EIA-28. The analysis and data presented in this report represents the operations of the Financial Reporting System companies in the context of their worldwide operations and in the context of the major energy markets which they serve. Both energy and nonenergy developments of these companies are analyzed. Although the focus is on developments in 1996, important trends prior to that time are also featured. Sections address energy markets in 1996; key financial developments; oil and gas exploration, development, and production; downstream petroleum in 1996; coal and alternative energy; and foreign direct investment in US energy. 30 figs., 104 tabs.

NONE

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fluoride hf produced" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

New policy imperatives for energy producers  

SciTech Connect (OSTI)

Conferences sponsored by the International Research Center for Energy and Economic Development are organized toward increasing the understanding of the multifaceted problems in energy - economic, technical, and political - that confront not just the consuming industrial powers but the developing OPEC and non-OPEC producers and, in particular, the Third World countries whose plight is extreme. All types were represented at this 6th conference, and the 21 papers mirror the diversity of ideas and, at the same time, the very real areas where cooperation and coordination are clearly both possible and desirable. A separate abstract was prepared for each paper for Energy Abstracts for Policy Analysis (EAPA); one abstract was selected for Energy Research Abstracts (ERA).

El Mallakh, R.; El Mallakh, D.H. (eds.)

1980-01-01T23:59:59.000Z

442

Superheater Corrosion Produced By Biomass Fuels  

SciTech Connect (OSTI)

About 90% of the world's bioenergy is produced by burning renewable biomass fuels. Low-cost biomass fuels such as agricultural wastes typically contain more alkali metals and chlorine than conventional fuels. Although the efficiency of a boiler's steam cycle can be increased by raising its maximum steam temperature, alkali metals and chlorine released in biofuel boilers cause accelerated corrosion and fouling at high superheater steam temperatures. Most alloys that resist high temperature corrosion protect themselves with a surface layer of Cr{sub 2}O{sub 3}. However, this Cr{sub 2}O{sub 3} can be fluxed away by reactions that form alkali chromates or volatilized as chromic acid. This paper reviews recent research on superheater corrosion mechanisms and superheater alloy performance in biomass boilers firing black liquor, biomass fuels, blends of biomass with fossil fuels and municipal waste.

Sharp, William (Sandy) [SharpConsultant] [SharpConsultant; Singbeil, Douglas [FPInnovations] [FPInnovations; Keiser, James R [ORNL] [ORNL

2012-01-01T23:59:59.000Z

443

Automated apparatus for producing gradient gels  

DOE Patents [OSTI]

Apparatus for producing a gradient gel which serves as a standard medium for a two-dimensional analysis of proteins, the gel having a density gradient along its height formed by a variation in gel composition, with the apparatus including first and second pumping means each including a plurality of pumps on a common shaft and driven by a stepping motor capable of providing small incremental changes in pump outputs for the gel ingredients, the motors being controlled, by digital signals from a digital computer, a hollow form or cassette for receiving the gel composition, means for transferring the gel composition including a filler tube extending near the bottom of the cassette, adjustable horizontal and vertical arms for automatically removing and relocating the filler tube in the next cassette, and a digital computer programmed to automatically control the stepping motors, arm movements, and associated sensing operations involving the filling operation.

Anderson, Norman L. (Clarendon Hills, IL)

1986-01-01T23:59:59.000Z

444

System and method for producing metallic iron  

DOE Patents [OSTI]

A hearth furnace for producing metallic iron material has a furnace housing having a drying/preheat zone, a conversion zone, a fusion zone, and optionally a cooling zone, the conversion zone is between the drying/preheat zone and the fusion zone. A moving hearth is positioned within the furnace housing. A hood or separation barrier within at least a portion of the conversion zone, fusion zone or both separates the fusion zone into an upper region and a lower region with the lower region adjacent the hearth and the upper region adjacent the lower region and spaced from the hearth. An injector introduces a gaseous reductant into the lower region adjacent the hearth. A combustion region may be formed above the hood or separation barrier.

Bleifuss, Rodney L; Englund, David J; Iwasaki, Iwao; Fosnacht, Donald R; Brandon, Mark M; True, Bradford G

2013-09-17T23:59:59.000Z

445

Broadband microwave burst produced by electron beams  

E-Print Network [OSTI]

Theoretical and experimental study of fast electron beams attracts a lot of attention in the astrophysics and laboratory. In the case of solar flares the problem of reliable beam detection and diagnostics is of exceptional importance. This paper explores the fact that the electron beams moving oblique to the magnetic field or along the field with some angular scatter around the beam propagation direction can generate microwave continuum bursts via gyrosynchrotron mechanism. The characteristics of the microwave bursts produced by beams differ from those in case of isotropic or loss-cone distributions, which suggests a new tool for quantitative diagnostics of the beams in the solar corona. To demonstrate the potentiality of this tool, we analyze here a radio burst occurred during an impulsive flare 1B/M6.7 on 10 March 2001 (AR 9368, N27W42). Based on detailed analysis of the spectral, temporal, and spatial relationships, we obtained firm evidence that the microwave continuum burst is produced by electron beams. For the first time we developed and applied a new forward fitting algorithm based on exact gyrosynchrotron formulae and employing both the total power and polarization measurements to solve the inverse problem of the beam diagnostics. We found that the burst is generated by a oblique beam in a region of reasonably strong magnetic fi