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Note: This page contains sample records for the topic "thermal ionization mass" 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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1

Electrospray Ionization Mass Spectrometry  

SciTech Connect

Electrospray Ionization (ESI) is a process whereby gas phase ions are created from molecules in solution. As a solution exits a narrow tube in the presence of a strong electric field, an aerosol of charged droplets are is formed that produces gas phase ions as they it desolvates. ESI-MS comprises the creation of ions by ESI and the determination of their mass to charge ratio (m/z) by MS.

Kelly, Ryan T.; Marginean, Ioan; Tang, Keqi

2014-06-13T23:59:59.000Z

2

Accurate and Precise Determination of Boron Isotopic Ratios at Low Concentration by Positive Thermal Ionization Mass Spectrometry Using Static Multicollection of Cs2BO2+ Ions  

Science Journals Connector (OSTI)

Accurate and Precise Determination of Boron Isotopic Ratios at Low Concentration by Positive Thermal Ionization Mass Spectrometry Using Static Multicollection of Cs2BO2+ Ions ... (1) A relatively large mass difference (10%) between the two isotopes and high volatility results in significant boron isotopic variation from ?70‰(2) to +75‰(3) in natural materials; thus, boron isotopes have numerous applications in geochemistry, isotope hydrology, oceanography, environmental sciences, cosmology, and nuclear technology. ... (2) Our method provided better long-term stability of NIST 951 standard compared to “Zoom Quad” mode when more than two isotopes were determined in addition to boron isotope. ...

Mao-yong He; Ying-kai Xiao; Zhang-dong Jin; Yun-qi Ma; Jun Xiao; Yan-ling Zhang; Chong-guang Luo; Fei Zhang

2013-05-29T23:59:59.000Z

3

Combined Atomic Force Microscope-Based Topographical Imaging and Nanometer Scale Resolved Proximal Probe Thermal Desorption/Electrospray Ionization-Mass Spectrometry  

SciTech Connect

Nanometer scale proximal probe thermal desorption/electrospray ionization mass spectrometry (TD/ESI-MS) was demonstrated for molecular surface sampling of caffeine from a thin film using a 30 nm diameter nano-thermal analysis (nano-TA) probe tip in an atomic force microscope (AFM) coupled via a vapor transfer line and ESI interface to a MS detection platform. Using a probe temperature of 350 C and a spot sampling time of 30 s, conical desorption craters 250 nm in diameter and 100 nm deep were created as shown through subsequent topographical imaging of the surface within the same system. Automated sampling of a 5 x 2 array of spots, with 2 m spacing between spots, and real time selective detection of the desorbed caffeine using tandem mass spectrometry was also demonstrated. Estimated from the crater volume (~2x106 nm3), only about 10 amol (2 fg) of caffeine was liberated from each thermal desorption crater in the thin film. These results illustrate a relatively simple experimental setup and means to acquire in automated fashion sub-micrometer scale spatial sampling resolution and mass spectral detection of materials amenable to TD. The ability to achieve MS-based chemical imaging with 250 nm scale spatial resolution with this system is anticipated.

Ovchinnikova, Olga S [ORNL; Nikiforov, Maxim [ORNL; Bradshaw, James A [ORNL; Jesse, Stephen [ORNL; Van Berkel, Gary J [ORNL

2011-01-01T23:59:59.000Z

4

Standard test method for isotopic analysis of hydrolyzed uranium hexafluoride and uranyl nitrate solutions by thermal ionization mass spectrometry  

E-Print Network (OSTI)

1.1 This method applies to the determination of isotopic composition in hydrolyzed nuclear grade uranium hexafluoride. It covers isotopic abundance of 235U between 0.1 and 5.0 % mass fraction, abundance of 234U between 0.0055 and 0.05 % mass fraction, and abundance of 236U between 0.0003 and 0.5 % mass fraction. This test method may be applicable to other isotopic abundance providing that corresponding standards are available. 1.2 This test method can apply to uranyl nitrate solutions. This can be achieved either by transforming the uranyl nitrate solution to a uranyl fluoride solution prior to the deposition on the filaments or directly by depositing the uranyl nitrate solution on the filaments. In the latter case, a calibration with uranyl nitrate standards must be performed. 1.3 This test method can also apply to other nuclear grade matrices (for example, uranium oxides) by providing a chemical transformation to uranyl fluoride or uranyl nitrate solution. 1.4 This standard does not purport to address al...

American Society for Testing and Materials. Philadelphia

2005-01-01T23:59:59.000Z

5

Applications of High-Resolution Electrospray Ionization Mass...  

NLE Websites -- All DOE Office Websites (Extended Search)

High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Applications of High-Resolution Electrospray Ionization Mass...

6

Ambient Ionization Mass Spectrometry Analysis Pertaining To Biofuel Process Development.  

E-Print Network (OSTI)

??Mass spectrometry (MS) has undergone a revolution with the introduction of a new group of desorption/ionization (DI) techniques known collectively as Ambient Ionization mass spectrometry.… (more)

Dendukuri, Sushma

2012-01-01T23:59:59.000Z

7

Miniature quadrupole mass spectrometer having a cold cathode ionization source  

DOE Patents (OSTI)

An improved quadrupole mass spectrometer is described. The improvement lies in the substitution of the conventional hot filament electron source with a cold cathode field emitter array which in turn allows operating a small QMS at much high internal pressures then are currently achievable. By eliminating of the hot filament such problems as thermally "cracking" delicate analyte molecules, outgassing a "hot" filament, high power requirements, filament contamination by outgas species, and spurious em fields are avoid all together. In addition, the ability of produce FEAs using well-known and well developed photolithographic techniques, permits building a QMS having multiple redundancies of the ionization source at very low additional cost.

Felter, Thomas E. (Livermore, CA)

2002-01-01T23:59:59.000Z

8

Determination of ultratrace boron concentrations in uranium oxide by isotope dilution-thermal ionization mass spectrometry using a simplified separation procedure  

Science Journals Connector (OSTI)

Exhaustive reviews on analytical methodologies and mass spectrometric instrumentation for the determination of boron in different matrices such as biological tissues,...1, 4, 5]. It is an established fact that Isotope

Radhika M. Rao; Ankush R. Parab; K. Sasi Bhushan; Suresh K. Aggarwal

2010-06-01T23:59:59.000Z

9

Soft ionization of thermally evaporated hypergolic ionic liquid aerosols  

SciTech Connect

Isolated ion pairs of a conventional ionic liquid, 1-Ethyl-3-Methyl-Imidazolium Bis(trifluoromethylsulfonyl)imide ([Emim+][Tf2N?]), and a reactive hypergolic ionic liquid, 1- Butyl-3-Methyl-Imidazolium Dicyanamide ([Bmim+][Dca?]), are generated by vaporizing ionic liquid submicron aerosol particles for the first time; the vaporized species are investigated by dissociative ionization with tunable vacuum ultraviolet (VUV) light, exhibiting clear intact cations, Emim+ and Bmim+, presumably originating from intact ion pairs. Mass spectra of ion pair vapor from an effusive source of the hypergolic ionic liquid show substantial reactive decomposition due to the internal energy of the molecules emanating from the source. Photoionization efficiency curves in the near threshold ionization region of isolated ion pairs of [Emim+][Tf2N?] ionic liquid vapor are compared for an aerosol source and an effusive source, revealing changes in the appearance energy due to the amount of internal energy in the ion pairs. The aerosol source has a shift to higher threshold energy (~;;0.3 eV), attributed to reduced internal energy of the isolated ion pairs. The method of ionic liquid submicron aerosol particle vaporization, for reactive ionic liquids such as hypergolic species, is a convenient, thermally ?cooler? source of isolated intact ion pairs in the gas phase compared to effusive sources.

University of California; ERC, Incorporated, Edwards Air Force Base; Air Force Research Laboratory, Edwards Air Force Base; National Synchrotron Radiation Research Center (NSRRC); Koh, Christine J.; Liu, Chen-Lin; Harmon, Christopher W.; Strasser, Daniel; Golan, Amir; Kostko, Oleg; Chambreau, Steven D.; L.Vaghjiani, Ghanshyam; Leone, Stephen R.

2012-03-16T23:59:59.000Z

10

Residential Thermal Mass Construction  

E-Print Network (OSTI)

The southwest has long known the value of building homes with high mass materials. The ancient Pueblo Indians found that by using "adobe" they could capture the energy necessary to survive the harsh desert climate. Our ancestors knew that a heavy...

Thieken, J. S.

1988-01-01T23:59:59.000Z

11

Subcellular analysis by laser ablation electrospray ionization mass spectrometry  

DOE Patents (OSTI)

In various embodiments, a method of laser ablation electrospray ionization mass spectrometry (LAESI-MS) may generally comprise micro-dissecting a cell comprising at least one of a cell wall and a cell membrane to expose at least one subcellular component therein, ablating the at least one subcellular component by an infrared laser pulse to form an ablation plume, intercepting the ablation plume by an electrospray plume to form ions, and detecting the ions by mass spectrometry.

Vertes, Akos; Stolee, Jessica A; Shrestha, Bindesh

2014-12-02T23:59:59.000Z

12

Ionization and transmission efficiency in an electrospray ionization-mass spectrometry interface  

SciTech Connect

The efficiency of sample ionization by electrospray ionization (ESI) and the transmission of the charged droplets and gas-phase ions through an ESI interface were investigated in order to advance the understanding of how these factors affect mass spectrometry (MS) sensitivity. In addition, the effects of the ES emitter distance to the inlet, solution flow rate, and inlet temperature to the ionization and transmission efficiency were characterized. Quantitative measurements of ES current loss throughout the ESI interface were accomplished by electrically isolating the front surface of the interface from the inner wall of the heated inlet capillary, enabling losses on the two surfaces to be distinguished. The ES current lost to the front surface of the ESI interface was also spatially profiled with a linear array of 340-µm-dia. electrodes placed adjacent to the inlet capillary entrance. Current transmitted as gas-phase ions was differentiated from charged droplets and solvent clusters by directly measuring sensitivity with a single quadrupole mass spectrometer. The study has revealed a large sampling efficiency into the inlet capillary (>90% at an emitter distance of 1 mm), a global rather than a local gas dynamic effect on the shape of the ES plume due to the gas flow conductance limit of the inlet capillary, a large (>80%) loss of analyte after transmission through the inlet due to incomplete desolvation at a solution flow rate of 1.0 µL/min, and a decrease in analyte peak intensity at lower temperatures, despite a large increase in ES current transmission efficiency. These studies provide a clearer understanding of the parameters affecting ion transmission into the mass spectrometer, and will serve to guide the design of more efficient instrument interfaces.

Page, Jason S.; Kelly, Ryan T.; Tang, Keqi; Smith, Richard D.

2007-09-01T23:59:59.000Z

13

Matrixassisted laser desorption/ionization mass spectrometric analysis of aliphatic biodegradable photoluminescent polymers  

E-Print Network (OSTI)

established that the new ILMs provided good spottospot reproducibility and high ionization efficiency compared/ionization mass spectrometry (MALDIMS). The polymers, formed by a condensation reaction of three components

Yang, Jian

14

New developments in biochemical mass spectrometry: Electrospray ionization  

SciTech Connect

The principles, development, and recent application of electrospray ionization-mass spectrometry (ESI-MS) to biological compounds are reviewed. ESI-MS methods now allow determination of accurate molecular weights for proteins extending to over 50,000, and in some cases well over 100,000. Similar capabilities are being developed for oligonucleotides. The instrumentation used for ESI-MS is briefly described and it is shown that, although ionization efficiency appears to be uniformly high, detector sensitivity may be directly correlated with molecular weight. The use of tandem mass spectrometry (e.g., MS/MS) for extending collision-induced dissociation (CID) methods to the structural studies of large molecules is described. For example, effective CID of various albumin species (molecular weight {approximately}66,000) can be obtained, far larger than obtainable for singly charged molecular ions. The combination of capillary electrophoresis, in both free solution zone electrophoresis and isotachophoresis formats, as well as microcolumn liquid chromatography with ESI-MS, provides the capability for on-line separation and analysis of subpicomole quantities of proteins. These and other new developments related to ESI-MS are illustrated by a range of examples. Fundamental considerations suggest even more impressive developments may be anticipated related to detection sensitivity and methods for obtaining structural information.

Smith, R.D.; Loo, J.A.; Edmonds, C.G.; Barinaga, C.J.; Udseth, H.R. (Pacific Northwest Laboratory, Richland, WA (USA))

1990-05-01T23:59:59.000Z

15

Electrospray ionization mass spectrometric characterization of acrylamide adducts to hemoglobin  

SciTech Connect

The most common procedure to identify hemoglobin adducts has been to cleave the adducts from the protein and characterize the adducting species, by, for example, derivatization and gas chromatography/mass spectrometry. To extend these approaches we used electrospray ionization mass spectrometry (ESI-MS) to characterize adducted hemoglobin. For this we incubated [[sup 14]C]acrylamide with the purified human hemoglobin (type A[sub 0]) under conditions that yielded high adduct levels. When the hemoglobin was separated by reversed-phase high-performance liquid chromatography (HPLC), 65% of the radioactivity copurified with the [beta]-subunit. Three adducted species were prominent in the ESI mass spectrum of the intact [beta]-subunit, indicating acrylamide adduction (i.e., mass increase of 71 Da) and two addition unidentified moieties with mass increments of 102 and 135 Da. Endoproteinase Glu-C digestion of the adducted [beta]-subunit resulted in a peptide mixture that, upon reversed-phase HPLC separation, provided several radiolabeled peptides. Using ESI-MS we identified these as the V[sub 91-101] and V[sub 102-122] peptides that represent the cysteine-containing peptides of the [beta]-subunit. These results provide definitive information on acrylamide-modified human hemoglobin and demonstrate that ESI-MS provides valuable structure information on chemically adducted proteins. 30 refs., 9 figs., 3 tabs.

Springer, D.L.; Goheen, S.C.; Edmonds, C.G. (Pacific Northwest Lab., Richland, WA (United States)); Bull, R.J.; Sylvester, D.M. (Washington State Univ., Pullman, WA (United States))

1993-01-01T23:59:59.000Z

16

Electrospray Ionization Mass Spectrometry of hexanitrohexaazaisowurtzitane (CL-20)  

SciTech Connect

Hexanitrohexaazaisowurtzitane, (C6H6N12O12, MW 438) {CL-20}, is a high-energy propellent that has been recently developed and successfully tested (Nielsen et al. 1998). CL-20 releases more energy on ignition and is more stable to accidental detonation than currently used energetic materials. It is expected to replace many of the energetic materials currently being used by the Department of Defense (DoD). The EPA method 8330 (EPA 1997) for the analysis of explosives and metabolites in soils calls for the use of UV/Vis detection. High performance liquid chromatography has been used to quantify CL-20 and precursor concentration (Bazaki et al. 1998`) at relatively high concentrations. Fourier transform infrared (FTIR) spectroscopy has been used to identify different crystal forms of CL-20 (4 isomers; Kim et al. 1998). Campbell et al. (1997) utilized particle beam mass spectrometry for the analysis of enzymatic degradation of explosives. Introduction and recent improvements of ionization techniques such as electrospray (ES) have allowed the mass spectrometer to become more widely used in liquid chromatography. Schilling(1996) also examined explosive components and metabolites using electrospray (ES) and atmospheric pressure chemical ionization (APCI) liquid chromatography/mass spectrometry (LC/MS). Schilling’s results showed that compared to thermospray LC/MS, APCI and ES were more sensitive than thermospray by at least an order of magnitude. 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX), 10 nitroso-RDX metabolites, and other munitions in ground water have been analyzed using solid phase extraction and isotope dilution liquid chromatography-APCI mass spectrometry (Cassada et al. 1999). The method detection limits indicate that nitramine and nitroaromatic compounds can be routinely determined in ground water samples using electrospray LC/MS with concentration techniques utilizing solid-phase extraction. Miller et al. (1996) studied nitrated explosives with mobile phase additives to enhance the ESI intensities and spectral consistencies. Several of the explosives gave nitrate adduct ions in the negative mode with ammonium nitrate as the mobile phase. The nitramines RDX and 1,3,5,7-tetranitro-1,3,5,7 tetraazacyclooctane (HMX) showed the greatest enhancement in response of the explosives. Ammonium nitrate was used as the mobile phase and made it possible to obtain consistent and interpretable LC/MS spectra at the nanogram level. Campbell et al. (1999), Shi et al. (2000), and Goheen et al. (1999) utilized electrospray ionization mass spectrometry for the identification of degradation products of explosives. Yinon et al. (1997) used ESI and tandem mass spectrometry collision-induced dissociation to examine several nitramine compounds including trinitrotolutene (TNT), RDX, and pentaerythritol tetranitrate (PETN). The results indicate that explosives can be detected in the negative ion mode and characterized by various adduct ions. As an example, for nitroglycerin, the major adduct ion observed was (M+ONO2)-. In addition, Harvey et al. (1992) have used direct probe mass spectrometry for the analysis of degradation products of tetryl and its transformation products in soil. The negative ion electrospray mass spectrum of CL-20 is reported here. The major adduct ions observed under negative ion conditions were (M+Cl)- at m/z 473 and (M+ONO2) – at m/z 500. In addition, the results of mass spectrometry/mass spectrometry studies are also discussed.

Campbell, James A.; Szecsody, Jim E.; Devary, Brooks J.; Valenzuela, Blandina R.

2007-09-03T23:59:59.000Z

17

Laser ablation electrospray ionization (LAESI) for atmospheric pressure, In vivo, and imaging mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation (LA) with electrospray ionization (ESI).

Vertes, Akos (Reston, VA); Nemes, Peter (Silver Spring, MD)

2011-11-29T23:59:59.000Z

18

Laser ablation electrospray ionization (LAESI) for atmospheric pressure, in vivo, and imaging mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Vertes, Akos; Nemes, Peter

2014-08-19T23:59:59.000Z

19

Laser ablation electrospray ionization (LAESI) for atmospheric pressure, in vivo, and imaging mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Vertes, Akos; Nemes, Peter

2013-07-16T23:59:59.000Z

20

Three-dimensional molecular imaging by infrared laser ablation electrospray ionization mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Vertes, Akos; Nemes, Peter

2013-07-16T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Three-dimensional molecular imaging by infrared laser ablation electrospray ionization mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Vertes, Akos; Nemes, Peter

2012-10-30T23:59:59.000Z

22

Detection of methoxylated anions of fullerenes by electrospray ionization mass spectrometry  

SciTech Connect

Electrospray ionization mass spectrometry (ESI-MS) has been applied to the study of the reactions of fullerenes in solution. The C[sub 60][sup [minus

Wilson, S.R.; Wu, Y. (New York Univ., NY (United States))

1993-11-03T23:59:59.000Z

23

Screening masses in thermal and dense medium  

E-Print Network (OSTI)

Screening masses of different hadronic states are studied in thermal and dense medium on lattice. It has been found that screening masses increase with the temperature. In deconfinement phase, chemical potential enhances the screening masses. We use the normalization with respect to lowest Matsubara frequency to characterize dissolving of hadronic bound states at high temperatures. It has been found that different hadronic states have different dissolving temperatures and their survivals are considerably improved at finite chemical potentials.

A. Tawfik

2006-05-29T23:59:59.000Z

24

An analysis of phase change material as thermal mass  

Science Journals Connector (OSTI)

...1006 40 117 An analysis of phase change material as thermal mass M.J Richardson...attenuated by thermal mass. Adding phase change material (PCM) to thermal mass increases...with heavyweight structures. phase change material|thermal mass|energy storage...

2008-01-01T23:59:59.000Z

25

The Thermal Mass limit of Neutron Cores  

E-Print Network (OSTI)

Static thermal equilibrium of a quantum self-gravitating ideal gas in General Relativity is studied at any temperature, taking into account the Tolman-Ehrenfest effect. Thermal contribution to the gravitational stability of static neutron cores is quantified. The curve of maximum mass with respect to temperature is reported. At low temperatures is recovered the Oppenheimer-Volkoff calculation, while at high temperatures is recovered the, recently reported, classical gas calculation. An ultimate upper mass limit $M = 2.43M_\\odot$ of all maximum values is found to occur at Tolman temperature $ T = 1.27mc^2$ with radius $R = 15.2km$.

Roupas, Zacharias

2014-01-01T23:59:59.000Z

26

Thermal rectification in quantum graded mass systems  

E-Print Network (OSTI)

We show the existence of thermal rectification in the graded mass quantum chain of harmonic oscillators with self-consistent reservoirs. Our analytical study allows us to identify the ingredients leading to the effect. The presence of rectification in this effective, simple model (representing graded mass materials, systems that may be constructed in practice) indicates that rectification in graded mass quantum systems may be an ubiquitous phenomenon. Moreover, as the classical version of this model does not present rectification, our results show that, here, rectification is a direct result of the quantum statistics.

Emmanuel Pereira

2010-03-01T23:59:59.000Z

27

Analysis of perchlorate in groundwater by electrospray ionization mass spectrometry/mass spectrometry  

SciTech Connect

An electrospray ionization mass spectrometry/mass spectrometry (ESI/MS/MS) method was developed to measure part-per-billion ({micro}g/L) concentrations of perchlorate in groundwater. Selective and sensitive perchlorate detection was achieved by operating the mass spectrometer in the negative ionization mode and by using MS/MS to monitor the CIO{sub 4}{sup {minus}} to ClO{sub 3}{sup {minus}} transition. The method of standard additions was used to address the considerable signal suppression caused by anions that are typically present in groundwater, such as bicarbonate and sulfate. ESI-MS/MS analysis was rapid, accurate, reproducible, and provided a detection limit of 0.5 {micro}g/L perchlorate in groundwater. Accuracy and precision of the ESI/MS/MS method were assessed by analyzing performance evaluation samples in a groundwater matrix and by comparing ion chromatography (IC) and ESI/MS/MS results for local groundwater samples. Results for the performance evaluation samples differed from the certified values by 4--13%, and precision ranged from 3 to 10% (relative standard deviation). The IC and ESI/MS/MS results were statistically indistinguishable for perchlorate concentrations above the detection limits of both methods.

Koester, C.J.; Beller, H.R.; Halden, R.U.

2000-05-01T23:59:59.000Z

28

High efficiency resonance ionization mass spectrometric analysis by external laser cavity enhancement techniques  

SciTech Connect

The demand to measure high dynamic range isotope ratios on small samples with resonance ionization mass spectrometry (RIMS) continues to increase. This paper discusses high ionization efficiency methods which can be applied to continuous wave (cw) RIMS to potentially achieve several tens of percent ionization efficiencies for certain elements. The primary technique under development to achieve this is an external laser cavity which can generate very high circulating laser powers. 12 refs., 3 figs.

Johnson, S.G.; Rios, E.L.; Miller, C.M.; Fearey, B.L.

1991-01-01T23:59:59.000Z

29

Characterization of nonpolar lipids and steroids by using laser-induced acoustic desorption/chemical ionization, atmospheric pressure chemical ionization, and electrospray ionization mass spectrometry  

SciTech Connect

Laser-induced acoustic desorption (LIAD) combined with ClMn(H{sub 2}O){sup +} chemical ionization (CI) was tested for the analysis of nonpolar lipids and selected steroids in a Fourier-transform ion cyclotron resonance mass spectrometer (FT-ICR). The nonpolar lipids studied, cholesterol, 5?-cholestane, cholesta-3,5-diene, squalene, and ?-carotene, were found to solely form the desired water replacement product (adduct-H{sub 2}O) upon reaction with the ClMn(H{sub 2}O){sup +} ions. The steroids, androsterone, dehydroepiandrosterone (DHEA), estrone, estradiol, and estriol, also form abundant adduct-H{sub 2}O ions, but less abundant adduct-2H{sub 2}O ions were also observed. Neither (+)APCI nor (+)ESI can ionize the saturated hydrocarbon lipid, cholestane. APCI successfully ionizes the unsaturated hydrocarbon lipids to form exclusively the intact protonated analytes. However, it causes extensive fragmentation for cholesterol and the steroids. The worst case is cholesterol that does not produce any stable protonated molecules. On the other hand, ESI cannot ionize any of the hydrocarbon analytes, saturated or unsaturated. However, ESI can be used to protonate the oxygen-containing analytes with substantially less fragmentation than for APCI in all cases except for cholesterol and estrone. In conclusion, LIAD/ClMn(H{sub 2}O){sup +} chemical ionization is superior over APCI and ESI for the mass spectrometric characterization of underivatized nonpolar lipids and steroids.

Jin, Z.; Daiya, S.; Kenttämaa, Hilkka I.

2011-01-01T23:59:59.000Z

30

Laser vaporization/ionization interface for coupling microscale separation techniques with mass spectrometry  

DOE Patents (OSTI)

The present invention provides a laser-induced vaporization and ionization interface for directly coupling microscale separation processes to a mass spectrometer. Vaporization and ionization of the separated analytes are facilitated by the addition of a light-absorbing component to the separation buffer or solvent. 8 figs.

Yeung, E.S.; Chang, Y.C.

1999-06-29T23:59:59.000Z

31

Desorption Electrospray Ionization Mass Spectrometry for Trace Analysis of Agrochemicals in Food  

Science Journals Connector (OSTI)

Desorption Electrospray Ionization Mass Spectrometry for Trace Analysis of Agrochemicals in Food ... Desorption electrospray ionization (DESI) is applied to the rapid, in situ, direct qualitative and quantitative (ultra)trace analysis of agrochemicals in foodstuffs. ... The results proved that DESI allows the detection and confirmation of traces of agrochemicals in actual market-purchased samples. ...

Juan F. García-Reyes; Ayanna U. Jackson; Antonio Molina-Díaz; R. Graham Cooks

2008-12-17T23:59:59.000Z

32

Quantifying Uranium Isotope Ratios Using Resonance Ionization Mass Spectrometry: The Influence of Laser Parameters on Relative Ionization Probability  

SciTech Connect

Resonance Ionization Mass Spectrometry (RIMS) has been developed as a method to measure relative uranium isotope abundances. In this approach, RIMS is used as an element-selective ionization process to provide a distinction between uranium atoms and potential isobars without the aid of chemical purification and separation. We explore the laser parameters critical to the ionization process and their effects on the measured isotope ratio. Specifically, the use of broad bandwidth lasers with automated feedback control of wavelength was applied to the measurement of {sup 235}U/{sup 238}U ratios to decrease laser-induced isotopic fractionation. By broadening the bandwidth of the first laser in a 3-color, 3-photon ionization process from a bandwidth of 1.8 GHz to about 10 GHz, the variation in sequential relative isotope abundance measurements decreased from >10% to less than 0.5%. This procedure was demonstrated for the direct interrogation of uranium oxide targets with essentially no sample preparation. A rate equation model for predicting the relative ionization probability has been developed to study the effect of variation in laser parameters on the measured isotope ratio. This work demonstrates that RIMS can be used for the robust measurement of uranium isotope ratios.

Isselhardt, B H

2011-09-06T23:59:59.000Z

33

Heating and Ionization of the Primordial Intergalactic Medium by High Mass X-ray Binaries  

E-Print Network (OSTI)

We investigate the influence of High Mass X-ray Binaries on their high redshift environments. Using a one-dimensional radiative transfer code, we predict the ionization and temperature profiles surrounding a coeval stellar population, composed of main sequence stars and HMXBs, at various times after its formation. We consider both uniform density surroundings, and a cluster embedded in a 10^8 solar mass NFW halo. HMXBs in a constant density environment produce negligible enhanced ionization because of their high-energy SEDs and short lifetimes. In this case, HMXBs only marginally contribute to the local heating rate. For NFW profiles, radiation from main sequence stars cannot prevent the initially ionized volume from recombining since it is unable to penetrate the high density galactic core. However, HMXB photons stall recombinations behind the front, keeping it partially ionized for longer. The increased electron density in these partially ionized regions promotes further cooling, resulting in lower IGM temp...

Knevitt, Gillian; Power, Chris; Bolton, James

2014-01-01T23:59:59.000Z

34

Evaluation of histone sequence and modifications by electrospray ionization mass spectrometry and tandem mass spectrometry  

SciTech Connect

The histones, together with other specialized proteins and DNA, form the extraordinarily complex structure of chromatin. Electrospray ionization (ESI) permits the promotion of such protein species into the gas phase as intact, multiply charged molecular species. Mass spectrometry (MS), using a linear quadrupole mass filter, permits measurement of the relative molecular mass of these intact species with precision and accuracy. The latter are sufficient to evaluate variations in the primary structure of the histones and the type and extent of the natural and induced multiple covalent modifications. The locations of modifications are revealed by tandem mass spectrometry using tandem linear quadrupole or ion trap instruments on the intact species or the modified peptides derived by selective proteolysis. Experiments in applying this technique to histones from K562, a human-derived cell line, have demonstrated variations in the profile of modification through the normal cell cycle and in the presence of agents that inhibit enzymes responsible for reversal of the modification. The authors are currently testing the hypothesis that ESI-MS will permit the sensitive and selective identification of insult-induced modifications, distinguishing them from natural cell-cycle changes. This will be possible because ESI-MS reveals the full details of the profile of multiple posttranslational modifications of histones.

Edmonds, C.G.; Loo, J.A.; Smith, R.D.; Fuciarelli, A.F.; Thrall, B.D.; Morris, J.E.; Springer, D.L. (Pacific Northwest Lab., Richland, WA (United States))

1993-01-01T23:59:59.000Z

35

Applications of HVAC System Utilizing Building Thermal Mass in Japan  

NLE Websites -- All DOE Office Websites (Extended Search)

Applications of HVAC System Utilizing Building Thermal Mass in Japan Applications of HVAC System Utilizing Building Thermal Mass in Japan Speaker(s): Katsuhiro Miura Date: January 27, 2012 - 10:00am Location: 90-3122 Seminar Host/Point of Contact: Michael Wetter Buildings have a large thermal capacity and it affects much on building thermal load for the HVAC system. The thermal mass can be utilized also to control the thermal load by storing thermal energy before HVAC operation. There are two ways to store thermal energy. One is by operating the HVAC system and the other is by natural ventilation, mainly at night. The latter could be combined with daily HVAC operation as a hybrid ventilation. Thermal mass storage is useful to decrease the hourly peak load and the daily thermal load and can be used for both cooling and heating purpose.

36

Fundamentals and Applications of Electrospray Ionization Mass Spectrometry for Petroleum Characterization  

Science Journals Connector (OSTI)

Fundamentals and Applications of Electrospray Ionization Mass Spectrometry for Petroleum Characterization ... We are reporting a study of the fundamental and application aspects of positive-ion electrospray ionization (ESI+) for petroleum characterization. ... The gas-phase basicities (GBs) were experimental data from the NIST Chemistry WebBook,33 whereas the aqueous basicities (pKb) were derived from Lange's Handbook of Chemistry, 14th Edition. ...

Kuangnan Qian; Kathleen E. Edwards; John H. Diehl; Larry A. Green

2004-09-10T23:59:59.000Z

37

High-Resolution Electrospray Ionization Mass Spectrometry Analysis...  

NLE Websites -- All DOE Office Websites (Extended Search)

Mass Spectrometry Analysis of Water- Soluble Organic Aerosols Collected with a Particle Abstract: This work demonstrates the utility of a particle-into-liquid sampler (PILS) a...

38

Direct determination of the adiabatic ionization energy of NO2 as measured by guided ion-beam mass spectrometry  

E-Print Network (OSTI)

Direct determination of the adiabatic ionization energy of NO2 as measured by guided ion-beam mass the past 60 years the value for the ionization energy (IE) of nitrogen dioxide has been measured many times, Utah 84112 (Received 16 April 1992; accepted 4 May 1992) The adiabatic ionization energy (IE) of NOa

Clemmer, David E.

39

Plume collimation for laser ablation electrospray ionization mass spectrometry  

DOE Patents (OSTI)

In various embodiments, a device may generally comprise a capillary having a first end and a second end; a laser to emit energy at a sample in the capillary to ablate the sample and generate an ablation plume in the capillary; an electrospray apparatus to generate an electrospray plume to intercept the ablation plume to produce ions; and a mass spectrometer having an ion transfer inlet to capture the ions. The ablation plume may comprise a collimated ablation plume. The device may comprise a flow cytometer. Methods of making and using the same are also described.

Vertes, Akos; Stolee, Jessica A.

2014-09-09T23:59:59.000Z

40

Elemental and isotopic analysis of inorganic salts by laser desorption ionization mass spectrometry  

SciTech Connect

Laser desorption ionization mass spectrometry is applied for the analysis of elements as well as their isotopic composition in different inorganic salts. At very low laser energies the inorganic ions are desorbed and ionized from the thin layer of the sample surface. The naturally occurring isotopes of alkali and silver ions are resolved using time of flight mass spectrometer. Further increase in laser energy shows the appearance of Al, Cr, and Fe ions in the mass spectra. This indicates the penetration laser beam beyond the sample surface leading to the ablation of sample target at higher energies. The simultaneous appearance of atomic ions from the sample target at relatively higher laser energies hampers the unambiguous identification of amino acid residues from the biomolecular ions in MALDI-MS.

Jayasekharan, T.; Sahoo, N. K. [Applied Spectroscopy Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

2013-02-05T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

SHORT CIRCUITS IN THERMALLY IONIZED PLASMAS: A MECHANISM FOR INTERMITTENT HEATING OF PROTOPLANETARY DISKS  

SciTech Connect

Many astrophysical systems of interest, including protoplanetary accretion disks, are made of turbulent magnetized gas with near-solar metallicity. Thermal ionization of alkali metals in such gas exceeds non-thermal ionization when temperatures climb above roughly 1000 K. As a result, the conductivity, proportional to the ionization fraction, gains a strong, positive dependence on temperature. In this paper, we demonstrate that this relation between the temperature and the conductivity triggers an exponential instability that acts similarly to an electrical short, where the increased conductivity concentrates the current and locally increases the Ohmic heating. This contrasts with the resistivity increase expected in an ideal magnetic reconnection region. The instability acts to focus narrow current sheets into even narrower sheets with far higher currents and temperatures. We lay out the basic principles of this behavior in this paper using protoplanetary disks as our example host system, motivated by observations of chondritic meteorites and their ancestors, dust grains in protoplanetary disks, that reveal the existence of strong, frequent heating events that this instability could explain.

Hubbard, Alexander; McNally, Colin P.; Mac Low, Mordecai-Mark, E-mail: ahubbard@amnh.org, E-mail: cmcnally@nbi.dk, E-mail: mordecai@amnh.org [Department of Astrophysics, American Museum of Natural History, 79th St. at Central Park West, New York, NY 10024-5192 (United States)

2012-12-10T23:59:59.000Z

42

Direct analysis of cellulose in poplar stem by matrixassisted laser desorption/ionization imaging mass spectrometry  

NLE Websites -- All DOE Office Websites (Extended Search)

analysis analysis of cellulose in poplar stem by matrix- assisted laser desorption/ionization imaging mass spectrometry Seokwon Jung 1,3 , Yanfeng Chen 3 , M. Cameron Sullards 1,3 and Arthur J. Ragauskas 1,2,3 * 1 BioEnergy Science Center, Georgia Institute of Technology, 500 10 th St., Atlanta, GA 30332, USA 2 Institute of Paper Science and Technology, Georgia Institute of Technology, 500 10 th St., Atlanta, GA 30332, USA 3 School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, GA 30332, USA Received 10 July 2010; Revised 9 August 2010; Accepted 23 August 2010 Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) was applied to the analysis of the spatial distribution of cellulose on a cross-section of juvenile poplar (Populus deltoids) stems. Microcrystalline cellulose (MCC) was used to optimize matrix (2,5-dihydroxybenzoic

43

High explosives vapor detection by atmospheric sampling glow discharge ionization/tandem mass spectrometry  

SciTech Connect

The combination of atmospheric sampling glow discharge ionization with tandem mass spectrometry for the detection of traces of high explosives is described. Particular emphasis is placed on use of the quadrupole ion trap as the type of tandem mass spectrometer. Atmospheric sampling glow discharge provides a simple, rugged, and efficient means for anion formation while the quadrupole ion trap provides for efficient tandem mass spectrometry. Mass selective ion accumulation and non-specific ion activation methods can be used to overcome deleterious effects arising from ion/ion interactions. Such interactions constitute the major potential technical barrier to the use of the ion trap for real-time monitoring of targeted compounds in uncontrolled and highly variable matrices. Tailored waveforms can be used to effect both mass selective ion accumulation and ion activation. Concatenated tailored waveforms allow for both functions in a single experiment thereby providing the capability for monitoring several targeted species simultaneously. The combination of atmospheric sampling glow discharge ionization with a state-of-the-art analytical quadrupole ion trap is a highly sensitive and specific detector for traces of high explosives. The combination is also small and inexpensive relative to virtually any other form of tandem mass spectrometry. The science and technology underlying the glow discharge/ion trap combination is sufficiently mature to form the basis for an engineering effort to make the detector portable. 85 refs.

McLuckey, S.A.; Goeringer, D.E.; Asano, K.G. [Oak Ridge National Lab., TN (United States). Chemical and Analytical Sciences Div.

1996-02-01T23:59:59.000Z

44

Demand Shifting With Thermal Mass in Large Commercial Buildings: Case  

NLE Websites -- All DOE Office Websites (Extended Search)

Demand Shifting With Thermal Mass in Large Commercial Buildings: Case Demand Shifting With Thermal Mass in Large Commercial Buildings: Case Studies and Tools Speaker(s): Peng Xu Date: March 9, 2007 - 12:00pm Location: 90-3122 The idea of pre-cooling and demand limiting is to pre-cool buildings at night or in the morning during off-peak hours, storing cooling energy in the building thermal mass and thereby reducing cooling loads during the peak periods. Savings are achieved by reducing on-peak energy and demand charges. The potential for utilizing building thermal mass for load shifting and peak demand reduction has been demonstrated in a number of simulation, laboratory, and field studies. Case studies in a number of office buildings in California has found that a simple demand limiting strategy reduced the chiller power by 20-100% (0.5-2.3W/ft2) during six

45

Direct analysis of samples by mass spectrometry: From elements to bio-molecules using laser ablation inductively couple plasma mass spectrometry and laser desorption/ionization mass spectrometry  

SciTech Connect

Mass spectrometric methods that are able to analyze solid samples or biological materials with little or no sample preparation are invaluable to science as well as society. Fundamental research that has discovered experimental and instrumental parameters that inhibit fractionation effects that occur during the quantification of elemental species in solid samples by laser ablation inductively coupled plasma mass spectrometry is described. Research that determines the effectiveness of novel laser desorption/ionization mass spectrometric methods for the molecular analysis of biological tissues at atmospheric pressure and at high spatial resolution is also described. A spatial resolution is achieved that is able to analyze samples at the single cell level.

Perdian, David C.

2009-08-19T23:59:59.000Z

46

Shotgun Approach for Quantitative Imaging of Phospholipids Using Nanospray Desorption Electrospray Ionization Mass Spectrometry  

SciTech Connect

Mass spectrometry imaging (MSI) has been extensively used for determining spatial distributions of molecules in biological samples, and there is increasing interest in using MSI for quantification. Nanospray desorption electrospray ionization, or nano-DESI, is an ambient MSI technique where a solvent is used for localized extraction of molecules followed by nanoelectrospray ionization. Doping the nano-DESI solvent with carefully selected standards enables online quantification during MSI experiments. In this proof-of-principle study, we demonstrate this quantification approach can be extended to provide shotgun-like quantification of phospholipids in thin brain tissue sections. Specifically, two phosphatidylcholine (PC) standards were added to the nano-DESI solvent for simultaneous imaging and quantification of 22 PC species observed in nano-DESI MSI. Furthermore, by combining the quantitative data obtained in the individual pixels, we demonstrate quantification of these PC species in seven different regions of a rat brain tissue section.

Lanekoff, Ingela T.; Thomas, Mathew; Laskin, Julia

2014-02-04T23:59:59.000Z

47

Characterization of the microdialysis junction interface for capillary electrophoresis/microelectrospray ionization mass spectrometry  

SciTech Connect

A capillary electrophoresis/electrospray ionization mass spectrometry (CE/ESI-MS) interface, based on an electric circuit across a microdialysis membrane surrounding a short capillary segment closely connected to the separation capillary terminus, is demonstrated to be sensitive, efficient, and rugged. A microspray type ionization emitter produces a stable electrospray at the low flow rates provided by CE and thus avoids both the need for a makeup liquid flow provided by liquid junction or sheath flow interfaces and the subsequent dilution and reduction in sensitivity. Reproducibility studies and comparisons with CE/UV and the CE/sheath flow interface with ESI-MS are presented. Additionally, postrun acidification via the microdialysis junction interface is demonstrated and shown to be capable of denaturing the holomyoglobin protein noncovalent complex while maintaining separation efficiency. 21 refs., 7 figs., 1 tab.

Severs, J.C.; Smith, R.D. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States)

1997-06-01T23:59:59.000Z

48

Real-time monitoring of volatile organic compounds using chemical ionization mass spectroscopy: Final report  

SciTech Connect

Volatile organic compound (VOC) emission to the atmosphere is of great concern to semiconductor manufacturing industries, research laboratories, the public, and regulatory agencies. Some industries are seeking ways to reduce emissions by reducing VOCs at the point of use (or generation). This paper discusses the requirements, design, calibration, and use of a sampling inlet/quadrupole mass spectrometer system for monitoring VOCs in a semiconductor manufacturing production line. The system uses chemical ionization to monitor compounds typically found in the lithography processes used to manufacture semiconductor devices (e.g., acetone, photoresist). The system was designed to be transportable from tool to tool in the production line and to give the operator real-time feedback so the process(es) can be adjusted to minimize VOC emissions. Detection limits ranging from the high ppb range for acetone to the low ppm range fore other lithography chemicals were achieved using chemical ionization mass spectroscopy at a data acquisition rate of approximately 1 mass spectral scan (30 to 200 daltons) per second. A demonstration of exhaust VOC monitoring was performed at a working semiconductor fabrication facility during actual wafer processing.

Thornberg, S.M.; Mowry, C.D.; Keenan, M.R.; Bender, S.F.A. [Sandia National Labs., Albuquerque, NM (United States). Gas Analysis Lab.; Owen, T. [Intel Corp., Rio Rancho, NM (United States)

1997-04-01T23:59:59.000Z

49

Toward Single-Cell Analysis by Plume Collimation in Laser Ablation Electrospray Ionization Mass Spectrometry  

Science Journals Connector (OSTI)

In the plume collimation experiments, laser radiation was delivered through a germanium oxide (GeO2) optical fiber (450 ?m core diameter, HP Fiber, Infrared Fiber Systems, Inc., Silver Spring, MD) with a tip etched in a 2% nitric acid solution as described earlier. ... Upon ablation in the capillary, a collimated plume emerges (shown in blue) and is ionized by an electrospray. ... Individual sea urchin eggs were selected by using the micromanipulator system and deposited into a capillary for LAESI mass spectrometry with plume collimation. ...

Jessica A. Stolee; Akos Vertes

2013-02-28T23:59:59.000Z

50

Observation of a small oligonucleotide duplex by electrospray ionization mass spectrometry  

SciTech Connect

Electrospray ionization (ESI) has been demonstrated to be a soft ionization technique, allowing accurate molecular weight determination for biopolymers due to gas-phase multiple charging. Recent results have demonstrated that noncovalent associations can be preserved upon transfer into the gas phase with ESI, providing a new approach to the determination of both structurally-specific and nonspecific noncovalent associations in solution. The mass spectrometric experimental conditions necessary to preserve such noncovalent associations, and the physical constraints upon such, have yet to be elucidated, although it is clear that gentle interface conditions minimizing internal excitation of noncovalent complexes are helpful. Base-paired oligonucleotide hybridization constitutes one of the most important and thoroughly studied noncovalent associations of biopolymers. Initial attempts to observe duplex oligonucleotides resulted in detection of only the monomeric constituents. Since then, the authors have developed interface conditions that are more gentle and yet still provide sufficient molecular ion desolvation to preserve such associations using new instrumentation with a greatly extended m/z range. In this communication, the authors report the successful ionization of duplex oligonucleotides and the conditions necessary for detection by negative ion ESI-MS. 6 refs., 1 fig.

Light-Wahl, K.J.; Springer, D.L.; Winger, B.E.; Edmonds, C.G.; Thrall, B.D.; Smith, R.D. (Pacific Northwest Lab., Richland, WA (United States)); Camp, D.G. II (Eastern Oregon State College, La Grande (United States))

1993-01-27T23:59:59.000Z

51

On-line microdialysis sample cleanup for electrospray ionization mass spectrometry of nucleic acid samples  

SciTech Connect

A major limitation of electrospray ionization mass spectrometry (ESI-MS) for oligonucleotide analysis arises due to sodium adduction, a problem that increases with molecular weight. Sodium adduction can preclude useful measurements when limited sample sizes prevent off-line cleanup. A novel and generally useful on-line microdialysis technique is described for the rapid (nearly 1-5 min) DNA sample cleanup for ESI-MS. Mass spectra of oligonucleotides of different size and sequence showing no significant sodium adduct peaks were obtained using the on-line microdialysis system with sodium chloride concentrations as high as 250 mM. Signal-to-noise ratios were also greatly enhanced compared to direct infusion of the original samples. By using ammonium acetate as the dialysis buffer, it was also found that the noncovalent association of double-stranded oligonucleotides could be preserved during the microdialysis process, allowing analysis by ESI-MS. 33 refs., 6 figs.

Liu, C.; Wu, Q.; Harms, A.C.; Smith, R.D. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States)

1996-09-15T23:59:59.000Z

52

Biases in Ion Transmission Through an Electrospray Ionization-Mass Spectrometry Capillary Inlet  

SciTech Connect

The standard heated capillary inlet of an electrospray ionization mass spectrometry (ESI-MS) interface was compared with shorter versions of the inlet to determine the effects on transmission and ionization efficiencies for low-flow electrosprays. The primary finding of the study was a large bias towards higher mobility species in the electrospray current losses to the inside walls of the inlet. The transmission efficiency increased with decreasing capillary length due to reduced losses along the capillary. A decrease in transmission efficiency was also confirmed for electrosprays of higher conductivity solvents. A direct correlation between mass spectrometry sensitivity and the transmitted electrospray current was not observed as some analytes showed little to no increase in sensitivity while others showed as high as a 15 – fold increase. The variation was shown to at least be partially dependent on the analytes’ mobilities. Higher mobility analytes demonstrated a larger increase in sensitivity when shorter inlets were used. The results indicate that considerable biases against higher mobility species can be produced by the use of long capillary inlets in the ESI-MS interface and strategies are provided to minimize the bias against higher mobility species for efficient ion transmission through the heated capillary interface.

Page, Jason S.; Marginean, Ioan; Baker, Erin Shammel; Kelly, Ryan T.; Tang, Keqi; Smith, Richard D.

2009-12-01T23:59:59.000Z

53

Atmospheric Pressure Photoionization Mass Spectrometry. Ionization Mechanism and the Effect of Solvent on the Ionization of Naphthalenes  

Science Journals Connector (OSTI)

13,14 To date, APPI-MS has been successfully used in the analysis of flavonoids,15 steroids,16,17 vitamins,18 antioxidants,19 pharmaceuticals,20-22 polyaromatic hydrocarbons,23,24 agrochemicals,25 and aromatic imines and amines. ... The ionization process in APPI directly depends on the reactant ion composition, which in turn depends on solvent, dopant, nebulizing gas, auxiliary gas, and impurities as well as components of the surrounding air. ... Next, the ionization efficiency and mechanism in APPI was studied with 7 naphthalenes in the same 13 solvent compositions. ...

Tiina J. Kauppila; Tiia Kuuranne; Eduardo C. Meurer; Marcos N. Eberlin; Tapio Kotiaho; Risto Kostiainen

2002-09-28T23:59:59.000Z

54

Observation of a noncovalent ribonuclease S-protein/S-peptide complex by electrospray ionization mass spectrometry  

SciTech Connect

Electrospray ionization mass spectrometry (ESI-MS) investigations of noncovalently-bound complexes are of great interest because of their relevance to solution biochemistry. ESI-MS is particularly well suited to studies of weak interactions because it is very gentle and it allows studies to be performed under physiological or near-physiological solution conditions. However, it is not yet fully understood which weakly-bound complexes known to exist in solution will be observable by ESI-MS, or what minimum binding strength may be required for ESI-MS observation. Also unclear is whether complexes observed by ESI-MS reflect only species present in the bulk solution, or whether complexes also reflect aggregation in electrospray-generated microdroplets. We address some of these issues by employing ribonuclease S (RNase-S) as a test of the applicability of ESI-MS for analysis of noncovalent complexes. These results show that the ESI mass spectra of R Nase-S can reflect the specificity of binding in solution. 33 refs., 2 figs.

Loo, R.R.O.; Goodlett, D.R.; Smith, R.D.; Loo, J.A. (Pacific Northwest Lab., Richland, WA (United States))

1993-05-19T23:59:59.000Z

55

Control of Analyte Electrolysis in Electrospray Ionization Mass Spectrometry Using Repetitively Pulsed High Voltage  

SciTech Connect

Analyte electrolysis using a repetitively pulsed high voltage ion source was investigated and compared to that using a regular, continuously operating direct current high voltage ion source in electrospray ionization mass spectrometry. The extent of analyte electrolysis was explored as a function of the length and frequency of the high voltage pulse using the model compound reserpine in positive ion mode. Using +5 kV as the maximum high voltage amplitude, reserpine was oxidized to its 2, 4, 6 and 8-electron oxidation products when direct current high voltage was employed. In contrast, when using a pulsed high voltage, oxidation of reserpine was eliminated by employing the appropriate high voltage pulse length and frequency. This effect was caused by inefficient mass transport of the analyte to the electrode surface during the duration of the high voltage pulse and the subsequent relaxation of the emitter electrode/ electrolyte interface during the time period when the high voltage was turned off. This mode of ESI source operation allows for analyte electrolysis to be quickly and simply switched on or off electronically via a change in voltage pulse variables.

Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2011-01-01T23:59:59.000Z

56

A Dual Platform for Selective Analyte Enrichment and Ionization in Mass Spectrometry Using Aptamer-Conjugated Graphene Oxide  

E-Print Network (OSTI)

A Dual Platform for Selective Analyte Enrichment and Ionization in Mass Spectrometry Using Aptamer/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan UniVersity, Changsha and detection platform for analytes from complex biological media. We have shown that cocaine and adenosine can

Tan, Weihong

57

Thermal ionization induced metal-semiconductor transition and room temperature ferromagnetism in trivalent doped ZnO codoped with lithium  

SciTech Connect

Thermal ionization induced metallic to semiconductor (MST) transition occurring at 460?K for Zn{sub 0.97}Al{sub 0.03}O, 463?K for Zn{sub 0.94}Al{sub 0.03}Li{sub 0.03}O, and 503?K for Zn{sub 0.91}Al{sub 0.03}Li{sub 0.03}Mn{sub 0.03}O has been found in the sol-gel synthesized (using hexamethylenetetramine), trivalent doped (Al, Mn) ZnO codoped with lithium. Increase in the thermally ionized carrier concentration due to Al doping is responsible for near band edge (NBE) peak shift causing Fermi level to move into conduction band making it metallic consistent with resistivity results. Free carrier (thermally activated) neutralization with ionized donor is responsible for semiconducting nature, which is supported from the free carrier screening produced energy shift in the NBE of photoluminescence peak. Furthermore, independently band gap shrinkage is also obtained from UV-Visible studies confirming localization induced MST. An anti-correlation is found between defect density (DLE) and room temperature ferromagnetism (RTFM) indicating intrinsic defects are not directly responsible for RTFM.

Sivagamasundari, A.; Chandrasekar, S.; Pugaze, R.; Kannan, R., E-mail: kannan@pec.edu [Department of Physics, Pondicherry Engineering College, Puducherry 605 014 (India); Rajagopan, S. [Department of Chemistry, Pondicherry Engineering College, Puducherry 605 014 (India)

2014-03-07T23:59:59.000Z

58

Point-defect optical transitions and thermal ionization energies from quantum Monte Carlo methods: Application to the F-center defect in MgO  

E-Print Network (OSTI)

We present an approach to calculation of point-defect optical and thermal ionization energies based on the highly accurate quantum Monte Carlo methods. The use of an inherently many-body theory that directly treats electron ...

Ertekin, Elif

59

Detection of Biosignatures by Geomatrix-Assisted Laser Desorption/Ionization (GALDI) Mass Spectrometry  

SciTech Connect

Identification of mineral-associated biosignatures is of significance for retrieving biochemical information from geological records here on Earth and detecting signs of life on other planets, such as Mars. The importance of the geomatrix for identifying amino acids (e.g., histidine, threonine, and cysteine) and small proteins (e.g., gramicidin S) was investigated by laser desorption Fourier transform mass spectrometry. The investigated geomatrices include analogues of Fe-bearing minerals such as hematite and Na-bearing evaporites (e.g., halite). Samples were prepared by two methods: 1) application of analyte to the geomatrix surface and 2) production of homogenous analyte:geomatrix mixtures. Comparison of the two sample preparation methods revealed that the mixing method produces a better signal/noise ratio than surface application for the analyses of amino acids. The composition of the geomatrix has a profound influence on the detection of biomolecules. Peaks corresponding to the cation-attached biomolecular ions were observed for the Na-bearing evaporite analogue. No detectable peaks for the biomolecular ion species were observed when the biomolecules were associated with Fe-bearing minerals. Instead, only minor peaks were observed that may correspond to ions from fragments of the biomolecules. Depending on the underlying mineral composition, geomatrix-assisted laser desorption/ionization shows promise for directly identifying biosignatures associated with minerals.

Jill R. Scott; Beizhan Yan; Daphne L. Stoner; J. Michelle Kotler; Nancy W. Hinman

2007-04-01T23:59:59.000Z

60

Observation of the noncovalent quaternary associations of proteins by electrospray ionization mass spectrometry  

SciTech Connect

The noncovalent tetrameric active forms of avidin, concanavalin A (Con A), and adult human hemoglobin (HbA[sub 0]) can be observed intact in the gas phase by electrospray ionization mass spectrometry (ESI-MS). The atmosphere-vacuum ESI interface conditions strongly influence the retention of these weak noncovalent solution associations into the gas phase, as well as the average extent of charging for the subunits upon dissociation. The known solution pH dependence of the dimer-tetramer equilibrium of Con A was observed by ESI-MS, and the intact heterodimeric and -tetrameric active forms of adult human HbA[sub 0], ([alpha][beta]) and ([alpha][beta])[sub 2], with the prosthetic heme groups could also be characterized by ESI-MS. Under harsher interface conditions a species corresponding to a trimer was observed for each of the proteins, a species not known to be formed under physiological conditions. Differences in the relative stabilities of these tetrameric proteins, formed from the known solution structures, are also qualitatively consistent with the gas-phase stability observed with ESI-MS by adjusting the atmosphere-vacuum interface conditions. The hemoglobin tetramer was found to be less stable in the gas phase than either the Con A or avidin tetramer, consistent with solution dissociation constants. 21 refs., 14 figs.

Light-Wahl, K.J.; Schwartz, B.L.; Smith, R.D. (Pacific Northwest Lab., Richland, WA (United States))

1994-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Chemical Characterization of Crude Petroleum Using Nanospray Desorption Electrospray Ionization Coupled with High-Resolution Mass Spectrometry  

SciTech Connect

Nanospray desorption electrospray ionization (nano-DESI) combined with high-resolution mass spectrometry was used for the first time for the analysis of liquid petroleum crude oil samples. The analysis was performed in both positive and negative ionization modes using three solvents one of which (acetonitrile/toluene mixture) is commonly used in petroleomics studies while two other polar solvents (acetonitrile/water and methanol/water mixtures) are generally not compatible with petroleum characterization using mass spectrometry. The results demonstrate that nano-DESI analysis efficiently ionizes petroleum constituents soluble in a particular solvent. When acetonitrile/toluene is used as a solvent, nano-DESI generates electrospray-like spectra. In contrast, strikingly different spectra were obtained using acetonitrile/water and methanol/water. Comparison with the literature data indicates that these solvents selectively extract water-soluble constituents of the crude oil. Water-soluble compounds are predominantly observed as sodium adducts in nano-DESI spectra indicating that addition of sodium to the solvent may be a viable approach for efficient ionization of water-soluble crude oil constituents. Nano-DESI enables rapid screening of different classes of compounds in crude oil samples using solvents that are rarely used for petroleum characterization.

Eckert, Peter A.; Roach, Patrick J.; Laskin, Alexander; Laskin, Julia

2012-02-07T23:59:59.000Z

62

Combining Laser Ablation/Liquid Phase Collection Surface Sampling and High-Performance Liquid Chromatography Electrospray Ionization Mass Spectrometry  

SciTech Connect

This paper describes the coupling of ambient pressure transmission geometry laser ablation with a liquid phase sample collection method for surface sampling and ionization with subsequent mass spectral analysis. A commercially available autosampler was adapted to produce a liquid droplet at the end of the syringe injection needle while in close proximity to the surface to collect the sample plume produced by laser ablation. The sample collection was followed by either flow injection or a high performance liquid chromatography (HPLC) separation of the extracted components and detection with electrospray ionization mass spectrometry (ESI-MS). To illustrate the analytical utility of this coupling, thin films of a commercial ink sample containing rhodamine 6G and of mixed isobaric rhodamine B and 6G dyes on glass microscope slides were analyzed. The flow injection and HPLC/ESI-MS analysis revealed successful laser ablation, capture and, with HPLC, the separation of the two compounds. The ablated circular area was about 70 m in diameter for these experiments. The spatial sampling resolution afforded by the laser ablation, as well as the ability to use sample processing methods like HPLC between the sample collection and ionization steps, makes this combined surface sampling/ionization technique a highly versatile analytical tool.

Ovchinnikova, Olga S [ORNL; Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2011-01-01T23:59:59.000Z

63

Strong thermal leptogenesis and the absolute neutrino mass scale  

E-Print Network (OSTI)

We show that successful strong thermal leptogenesis, where the final asymmetry is independent of the initial conditions and in particular a large pre-existing asymmetry is efficiently washed-out, favours values of the lightest neutrino mass $m_1 \\gtrsim 10\\,{\\rm meV}$ for normal ordering (NO) and $m_1 \\gtrsim 3\\,{\\rm meV}$ for inverted ordering (IO) for models with orthogonal matrix entries respecting $|\\Omega_{ij}^2| \\lesssim 2$. . We show analytically why lower values of $m_1$ require a high level of fine tuning in the seesaw formula and/or in the flavoured decay parameters (in the electronic for NO, in the muonic for IO). We also show how this constraint exists thanks to the measured values of the neutrino mixing angles and can be tighten by a future determination of the Dirac phase. Our analysis also allows to place more stringent constraint for a specific model or class of models, such as $SO(10)$-inspired models, and shows that some models cannot realise strong thermal leptogenesis for any value of $m_1$. A scatter plot analysis fully supports the analytical results. We also briefly discuss the interplay with absolute neutrino mass scale experiments concluding that they will be able in the coming years to either corner strong thermal leptogenesis or find positive signals pointing to a non-vanishing $m_1$. Since the constraint is much stronger for NO than for IO, it is very important that new data from planned neutrino oscillation experiments will be able to solve the ambiguity.

Pasquale Di Bari; Sophie E. King; Michele Re Fiorentin

2014-03-24T23:59:59.000Z

64

Detection of Chemical Weapon Agents and Simulants Using Chemical Ionization Reaction Time-of-Flight Mass Spectrometry  

Science Journals Connector (OSTI)

Detection of Chemical Weapon Agents and Simulants Using Chemical Ionization Reaction Time-of-Flight Mass Spectrometry ... Chemical weapons were first used on a large scale in warfare in World War 1, where chlorine and sulfur mustard were used extensively. ... Many analytical methods have been developed for the detection of the active chemical constituents of chemical weapons, chemical weapon agents (CWAs), and their breakdown products in soil,5-9 groundwater,10,11 and air. ...

Rebecca L. Cordell; Kerry A. Willis; Kevin P. Wyche; Robert S. Blake; Andrew M. Ellis; Paul S. Monks

2007-09-26T23:59:59.000Z

65

Atmospheric Amines and Ammonia Measured with a Chemical Ionization Mass Spectrometer (CIMS)  

SciTech Connect

We report ambient measurements of amines and ammonia with a fast response chemical ionization mass spectrometer (CIMS) in a Southeastern U.S. forest in Alabama and a moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv) and ammonia (up to 2 ppbv) were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1-C6) at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast U.S. At the moderately polluted Kent site, higher concentrations of amines (C1-C6, from pptv to tens of pptv) and ammonia (up to 6 ppbv) were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

You, Y.; Kanawade, V. P.; de Gouw, J. A.; Guenther, Alex B.; Madronich, Sasha; Sierra-Hernandez, M. R.; Lawler, M.; Smith, James N.; Takahama, S.; Ruggeri, G.; Koss, A.; Olson, K.; Baumann, K.; Weber, R. J.; Nenes, A.; Guo, H.; Edgerton, Eric S.; Porcelli, L.; Brune, W. H.; Goldstein, Allen H.; Lee, S.-H

2014-11-19T23:59:59.000Z

66

Fully Automated Laser Ablation Liquid Capture Sample Analysis using NanoElectrospray Ionization Mass Spectrometry  

SciTech Connect

RATIONALE: Laser ablation provides for the possibility of sampling a large variety of surfaces with high spatial resolution. This type of sampling when employed in conjunction with liquid capture followed by nanoelectrospray ionization provides the opportunity for sensitive and prolonged interrogation of samples by mass spectrometry as well as the ability to analyze surfaces not amenable to direct liquid extraction. METHODS: A fully automated, reflection geometry, laser ablation liquid capture spot sampling system was achieved by incorporating appropriate laser fiber optics and a focusing lens into a commercially available, liquid extraction surface analysis (LESA ) ready Advion TriVersa NanoMate system. RESULTS: Under optimized conditions about 10% of laser ablated material could be captured in a droplet positioned vertically over the ablation region using the NanoMate robot controlled pipette. The sampling spot size area with this laser ablation liquid capture surface analysis (LA/LCSA) mode of operation (typically about 120 m x 160 m) was approximately 50 times smaller than that achievable by direct liquid extraction using LESA (ca. 1 mm diameter liquid extraction spot). The set-up was successfully applied for the analysis of ink on glass and paper as well as the endogenous components in Alstroemeria Yellow King flower petals. In a second mode of operation with a comparable sampling spot size, termed laser ablation/LESA , the laser system was used to drill through, penetrate, or otherwise expose material beneath a solvent resistant surface. Once drilled, LESA was effective in sampling soluble material exposed at that location on the surface. CONCLUSIONS: Incorporating the capability for different laser ablation liquid capture spot sampling modes of operation into a LESA ready Advion TriVersa NanoMate enhanced the spot sampling spatial resolution of this device and broadened the surface types amenable to analysis to include absorbent and solvent resistant materials.

Lorenz, Matthias [ORNL] [ORNL; Ovchinnikova, Olga S [ORNL] [ORNL; Van Berkel, Gary J [ORNL] [ORNL

2014-01-01T23:59:59.000Z

67

Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry: a Fundamental Shift in the Routine Practice of Clinical Microbiology  

Science Journals Connector (OSTI)

...Desorption Ionization-Time of Flight Mass Spectrometry: a Fundamental Shift in the Routine Practice of Clinical Microbiology Andrew...ability to absorb specific laser wavelengths, resulting in electronic excitation of the matrix. A list of matrices commonly used...

Andrew E. Clark; Erin J. Kaleta; Amit Arora; Donna M. Wolk

2013-07-01T23:59:59.000Z

68

Upgrade of the Resonance Ionization Mass Spectrometer for Precise Identification of Failed Fuel in a Fast Reactor  

SciTech Connect

Isotopic analysis of krypton (Kr) and xenon (Xe) by resonance ionization mass spectrometry (RIMS) is an effective tool for identification of failed fuel in fast reactors to achieve their safety operation and high plant availability. Reliability of the failed fuel detection and location (FFDL) system depends on the precise determination of {sup 78}Kr/{sup 80}Kr, {sup 82}Kr/{sup 80}Kr and {sup 126}Xe/{sup 129}Xe isotopic ratios, which is mainly hampered by statistical errors for detection of the corresponding isotopes except {sup 82}Kr generated in large amounts during operation of fast reactors. In this paper, we report on improvements of the laser optical system of our spectrometer to increase the resonance ionization efficiency of Kr and Xe atoms, focusing on (i) utilization of the uniform YAG laser beam to improve the wavelength conversion efficiency of sum frequency generation and (ii) reflection of the ultraviolet light by a concave mirror to increase the photon density. The results indicate that our upgraded resonance ionization mass spectrometer has enough performance for isotopic analysis of Kr and Xe required in the Monju FFDL system.

Iwata, Yoshihiro; Ito, Chikara [Experimental Fast Reactor Department, Oarai Research and Development Center, Japan Atomic Energy Agency, 4002 Narita, Oarai, Ibaraki 311-1393 (Japan); Harano, Hideki [National Institute of Advanced Industrial Science and Technology, Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Aoyama, Takafumi [Experimental Fast Reactor Department, Oarai Research and Development Center, Japan Atomic Energy Agency, 4002 Narita, Oarai, Ibaraki 311-1393 (Japan); Research Institute of Nuclear Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507 (Japan)

2011-12-13T23:59:59.000Z

69

Thermal rectification and negative differential thermal resistance in lattices with mass gradient Nuo Yang,1 Nianbei Li,1 Lei Wang,1 and Baowen Li1,2,  

E-Print Network (OSTI)

Thermal rectification and negative differential thermal resistance in lattices with mass gradient thermal resistance is observed. Possible applications in constructing thermal rectifiers and thermal properties, the thermal properties of graded materials have not yet been fully studied see the recent review

Li, Baowen

70

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

SciTech Connect

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

71

Improving liquid chromatography-mass spectrometry sensitivity using a subambient pressure ionization with nanoelectrospray (SPIN) interface  

SciTech Connect

In this work the Subambient Pressure Ionization with Nanoelectrospray (SPIN) ion source and interface which operates at ~15-30 Torr is demonstrated to be compatible with gradient reversed-phase liquid chromatography-MS applications, exemplified here with the analysis of complex samples (a protein tryptic digest and a whole cell lysate). A low liquid chromatographic flow rate (100-400 nL/min) allowed stable electrospray to be established while avoiding electrical breakdown. Efforts to increase the operating pressure of the SPIN source relative to previously reported designs prevented solvent freezing and enhanced charged cluster/droplet desolvation. A 5-12-fold improvement in sensitivity relative to a conventional atmospheric pressure nanoelectrospray ionization (ESI) source was obtained for detected peptides.

Tang, Keqi; Page, Jason S.; Marginean, Ioan; Kelly, Ryan T.; Smith, Richard D.

2011-04-22T23:59:59.000Z

72

Time-Resolved Molecular Characterization of Limonene/Ozone Aerosol using High-Resolution Electrospray Ionization Mass Spectrometry  

SciTech Connect

Molecular composition of limonene/O3 secondary organic aerosol (SOA) was investigated using high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) as a function of reaction time. SOA was generated by ozonation of D-limonene in a reaction chamber and sampled at different time intervals using a cascade impactor. The SOA samples were extracted into acetonitrile and analyzed using a HR-ESI-MS instrument with a resolving power of 100,000 (m/?m). The resulting mass spectra provided detailed information about the extent of oxidation inferred from the O:C ratios, double bond equivalency (DBE) factors, and aromaticity indexes (AI) in hundreds of identified individual SOA species.

Bateman, Adam P.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

2009-09-09T23:59:59.000Z

73

Real-Time, On-Line Characterization of Diesel Generator Air Toxic Emissions by Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry  

Science Journals Connector (OSTI)

Real-Time, On-Line Characterization of Diesel Generator Air Toxic Emissions by Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry ... For the same reasons, the far more abundant exhaust gases such as nitrogen, water, and carbon dioxide cannot be ionized and, therefore, do not interfere with the potential detection of low (2?100 pptv) concentrations of organic molecules. ... The sample was introduced into the ionization chamber (Figure 1) through a modified pulsed valve (General Valve Series 99) that delivers 150-?s sample pulses at atmospheric back pressure through a 0.5-mm orifice at a repetition rate of 10 Hz. ...

Lukas Oudejans; Abderrahmane Touati; Brian K. Gullett

2004-03-24T23:59:59.000Z

74

Rapid determination of 5-hydroxymethylfurfural by DART ionization with time-of-flight mass spectrometry  

Science Journals Connector (OSTI)

DART (direct analysis in real time), a novel technique with wide potential for rapid screening analysis, coupled with high-resolution time-of-flight mass spectrometry (TOF-MS) has been used for quantitative analy...

Aleš Rajchl; Ladislava Drgová; Adéla Grégrová…

2013-05-01T23:59:59.000Z

75

Electrospray ionization–tandem mass spectrometry analysis of phospholipid molecular species from Antarctic and non-Antarctic yeasts  

Science Journals Connector (OSTI)

Abstract High performance liquid chromatography-electrospray ionization tandem mass spectrometry was applied to the comprehensive analysis of phospholipids from seven Antarctic and seven non-Antarctic yeasts. Identification of specific fatty acyl moieties to the sn-1 and sn-2 positions of phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylserine (PS) and phosphatidylinositol (PI) were determined by relative abundance of fragment ions associated with formation of carboxylate anions and loss of fragment ions as free fatty carboxylic acid and ketene. Modulations with growth temperature in fatty acyl moieties in the sn-1 and sn-2 positions were characterized. Principal component analysis demonstrated that PE, PC and to a lesser extent PS, but not PI, were grouped into three distinct clusters consisting of seven Antarctic yeasts (Cryptococcus victoriae, Holtermanniella wattica, H. nyarrowii, Candida psychrophila, Leucosporidium fellii, Glaciozyma antarctica, Rhodotorula mucilaginosa), four non-Antarctic yeasts (C. albicans, Zygosaccharomyces rouxii, Cr. humicolus, R. mucilaginosa) and three strains of Saccharomyces cerevisiae.

Mohammad Bhuiyan; David Tucker; Kenneth Watson

2014-01-01T23:59:59.000Z

76

Thermal mass performance in residential construction : an energy analysis using a cube model  

E-Print Network (OSTI)

Given the pervasiveness of energy efficiency concerns in the built environment, this research aims to answer key questions regarding the performance of thermal mass construction. The work presents the Cube Model, a simplified ...

Ledwith, Alison C. (Alison Catherine)

2012-01-01T23:59:59.000Z

77

Energy Efficient Process Heating: Insulation and Thermal Mass Kevin Carpenter and Kelly Kissock  

E-Print Network (OSTI)

1 Energy Efficient Process Heating: Insulation and Thermal Mass Kevin Carpenter and Kelly Kissock-0210 Phone: (937) 229-2852 Fax: (937) 229-4766 Email: Kelly.Kissock@notes.udayton.edu ABSTRACT Open tanks

Kissock, Kelly

78

Cooling Strategies Based on Indicators of Thermal Storage in Commercial Building Mass  

E-Print Network (OSTI)

specific instance of this phenomenon, in which thermal storage by building mass over weekends exacerbates Monday cooling energy requirements. The study relies on computer simulations of energy use for a large, office building prototype in El Paso, TX using...

Eto, J. H.

1985-01-01T23:59:59.000Z

79

Resonance enhanced multiphonon ionization of silicon produced during disilane pyrolysis  

Science Journals Connector (OSTI)

Gas phase species generated by thermal decomposition of disilane were studied using resonance enhanced multiphoton ionization at disilane pressures ranging from 1–10 Torr and temperatures ranging from 300–1000 K. Atomic Si mass 28 was observed at 487.9 417.7 and 416.2 nm. A mass?30 signal was not observed between 494–515 nm. Masses 2 32 and 60 were observed using multiphonon ionization and were photoionization fragments from higher silanes and silenes. Thermal decomposition reactions were the main source of atomic Si for the mass?28 signal although ionization of SiH2 and higher silanes followed by fragmentation may have contributed some of the mass?28 signal.

Justine E. Johannes; John G. Ekerdt

1994-01-01T23:59:59.000Z

80

High-lying bound Rydberg states of excited Hg(6s6p {sup 3}P{sub 1}) atoms from two-color resonance ionization mass spectroscopy  

SciTech Connect

Mercury isotopes are investigated with two-color resonance ionization mass spectroscopy (RIMS). Isotope shifts, hyperfine structure splittings, and the lifetime of the intermediate 6s6p {sup 3}P{sub 1} state are determined by RIMS. Ion yields at the threshold region in various static electric fields are measured in order to determine an extrapolated ionization energy value at zero field strength. New energy values for high-lying bound 6s nd {sup 3}D (21ionization. To the author's knowledge this is the first time that isotopic effects on the ionization energy are deduced from the convergence limit of the Rydberg series.

Bisling, Peter; Dederichs, Jan; Neidhart, Bernd; Weitkamp, Claus [GKSS-Forschungszentrum Geesthacht GmbH, Postfach 11 60, D-21494 Geesthacht (Germany)

1998-12-16T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Ion fragmentation in an electrospray ionization mass spectrometer interface with different gases  

E-Print Network (OSTI)

in the gas phase. However, particularly in multi- component samples, this may not be enough to unambigu predicts that the degree of ion fragmentation increases with increasing mass of the curtain gas. However with argon and krypton is caused by condensation of the gases within the free jet expansion between

Chen, David D.Y.

82

Using electrospray ionization FTICR mass spectrometry to study competitive binding of inhibitors to carbonic anhydrase  

SciTech Connect

We report a method based on mass spectrometry for the characterization of noncovalent complexes of proteins with mixtures of ligands; this method is relevant to the study of drug leads and may be useful in screening libraries for tight-binding compounds. This study describes the competitive binding of inhibitors derived from para-substituted benzenesulfonamides to bovine carbonic anhydrase II (BCAII, EC 4.2.1.1) using this technique. Relative binding constants and structural information for a mixture of inhibitors can be obtained in a single experiment using ESI-FTICR-MS. The work demonstrates that ESI-MS has significant potential for measuring relative binding affinities and characterizing the structures of ligands associated noncovalently to proteins. We have detected noncovalent complexes in the gas phase for ligands having values of K{sub b} as low as 1.7 x 10{sup 6} M{sup -1} in solution. The technique also allowed identification of tightbinding ligands from small libraries. The structures of inhibitors having similar masses can be identified by the high-resolution and multistep dissociation mass spectrometry of which FTICR is uniquely capable. This range of capabilities for ESI-FTICR-MS should be widely useful in medicinal chemistry. 22 refs., 2 figs.

Cheng, X.; Chen, R.; Bruce, J.E.; Schwartz, B.L.; Anderson, G.A.; Hofstadler, S.A.; Gale, D.C.; Smith, R.D. [Pacific Northwest Lab., Richland, WA (United States); Gao, J.; Sigal, G.B.; Mammen, M.; Whitesides, G.M. [Harvard Univ., Cambridge, MA (United States)

1995-08-30T23:59:59.000Z

83

IONIZATION IN ATMOSPHERES OF BROWN DWARFS AND EXTRASOLAR PLANETS. V. ALFVÉN IONIZATION  

SciTech Connect

Observations of continuous radio and sporadic X-ray emission from low-mass objects suggest they harbor localized plasmas in their atmospheric environments. For low-mass objects, the degree of thermal ionization is insufficient to qualify the ionized component as a plasma, posing the question: what ionization processes can efficiently produce the required plasma that is the source of the radiation? We propose Alfvén ionization as a mechanism for producing localized pockets of ionized gas in the atmosphere, having sufficient degrees of ionization (?10{sup –7}) that they constitute plasmas. We outline the criteria required for Alfvén ionization and demonstrate its applicability in the atmospheres of low-mass objects such as giant gas planets, brown dwarfs, and M dwarfs with both solar and sub-solar metallicities. We find that Alfvén ionization is most efficient at mid to low atmospheric pressures where a seed plasma is easier to magnetize and the pressure gradients needed to drive the required neutral flows are the smallest. For the model atmospheres considered, our results show that degrees of ionization of 10{sup –6}-1 can be obtained as a result of Alfvén ionization. Observable consequences include continuum bremsstrahlung emission, superimposed with spectral lines from the plasma ion species (e.g., He, Mg, H{sub 2}, or CO lines). Forbidden lines are also expected from the metastable population. The presence of an atmospheric plasma opens the door to a multitude of plasma and chemical processes not yet considered in current atmospheric models. The occurrence of Alfvén ionization may also be applicable to other astrophysical environments such as protoplanetary disks.

Stark, C. R.; Helling, Ch.; Rimmer, P. B. [SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS (United Kingdom); Diver, D. A., E-mail: craig.stark@st-andrews.ac.uk [SUPA, School of Physics and Astronomy, Kelvin Building, University of Glasgow, Glasgow, G12 8QQ (United Kingdom)

2013-10-10T23:59:59.000Z

84

Thermal gauge boson masses of the electroweak theory in the broken phase  

Science Journals Connector (OSTI)

Thermal effects in the broken phase of the electroweak theory are studied in the strongly interacting Higgs boson limit. In that limit and at the tree level the bosonic sector of the theory is a gauged non-linear sigma model. The associated one-loop thermal effective action for soft fields is then computed by using the background field method together with the Stueckelberg formalism. This effective action describes thermal corrections to the masses of the gauge bosons W, Z and the photon. It is the proper generalization of the hard thermal effective action of a Yang-Mills theory when there is a Higgs mechanism for a heavy Higgs particle.

Cristina Manuel

1998-05-19T23:59:59.000Z

85

Effect of Surface Mass on Roof Thermal Performance  

E-Print Network (OSTI)

net heat flow through the roof. This paper presents some results of a combined experimental and analytical study to quantify the effects of surface mass. Measurements were made on roof test panels that were exposed to the weather of eastern Tennessee...

Wilkes, K. E.; Shipp, P. H.; Sanders, J. P.

1988-01-01T23:59:59.000Z

86

Exploring the Optimal Thermal Mass to Investigate the Potential of a Novel Low-Energy House Concept  

E-Print Network (OSTI)

the benefits of buildings with low and high thermal mass by applying hybrid adaptable thermal storage (HATS) systems and materials to a lightweight building. The HATS concept increases building performance and the robustness to changing user behavior, seasonal...

Hoes, P. J.; Trcka, M.; Hensen, J.; Bonnema, B.

2010-01-01T23:59:59.000Z

87

Applications of High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Secondary Organic Aerosols  

SciTech Connect

The applicability of high resolution electrospray ionization mass spectrometry (HR ESI-MS) to measurements of the average oxygen to carbon ratio (O/C) in organic aerosols was investigated. Solutions with known average O/C containing up to 10 standard compounds representative of secondary organic aerosol (SOA) were analyzed and corresponding electrospray ionization efficiencies were quantified. The assumption of equal ionization efficiency commonly used in estimating O/C ratios of organic aerosols was found to be reasonably accurate. We found that the accuracy of the measured O/C ratios increases by averaging the values obtained from both (+) and (-) modes. A correlation was found between the ratio of the ionization efficiencies in the positive and negative ESI modes with the octanol-water partition constant, and more importantly, with the compound's O/C. To demonstrate the utility of this correlation for estimating average O/C values of unknown mixtures, we analyzed the ESI (+) and ESI (-) data for SOA produced by oxidation of limonene and isoprene and compared to online O/C measurements using an aerosol mass spectrometer (AMS). This work demonstrates that the accuracy of the HR ESI-MS methods is comparable to that of the AMS, with the added benefit of molecular identification of the aerosol constituents.

Bateman, Adam P.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey

2012-07-02T23:59:59.000Z

88

The performance check between whole building thermal performance criteria and exterior wall measured clear wall R-value, thermal bridging, thermal mass, and airtightness  

SciTech Connect

At the last IEA Annex 32 meeting it was proposed that the annex develop the links between level 1 (the whole building performance) and level 2 (the envelope system). This paper provides a case study of just that type of connection. An exterior wall mockup is hot box tested and modeled in the laboratory. Measurements of the steady state and dynamic behavior of this mockup are used as the basis to define the thermal bridging, thermal mass benefit and air tightness of the whole wall system. These level two performance characteristics are related to the whole building performance. They can be analyzed by a finite difference modeling of the wall assembly. An equivalent wall theory is used to convert three dimensional heat flow to one dimensional terms that capture thermal mass effects, which in turn are used in a common whole building simulation model. This paper illustrates a performance check between the thermal performance of a Massive ICF (Insulating Concrete Form) wall system mocked up (level 2) and Whole Building Performance criteria (level 1) such as total space heating and cooling loads (thermal comfort).

Kosny, J.; Christian, J.E.; Desjarlais, A.O. [Oak Ridge National Lab., TN (United States). Buildings Technology Center; Kossecka, E. [Polish Academy of Sciences (Poland); Berrenberg, L. [American Polysteel Forms (United States)

1998-06-01T23:59:59.000Z

89

New perspectives in laser analytics: Resonance-enhanced multiphoton ionization in a Paul ion trap combined with a time-of-flight mass spectrometer  

SciTech Connect

A new laser analytical device has been developed that is based on resonance-enhanced multiphoton ionization in the very center of a radio-frequency quadrupole ion trap. Applications in speciation anlaysis of biological and enviromental samples and in materials science will all benefit from laser-optical selectivity in the resonance excitation process, combined with mass-spectropic sensivity which is further enhanced by the ion accumulation and storage capability.

Bisling, Peter; Heger, Hans Joerg; Michaelis, Walfried; Weitkamp, Claus; Zobel, Harald [GKSS-Forschungszentrum Geesthacht GmbH, Postfach 11 60, D-21494 Geesthacht (Germany)

1995-04-01T23:59:59.000Z

90

1,5-Diaminonaphthalene Hydrochloride Assisted Laser Desorption/Ionization Mass Spectrometry Imaging of Small Molecules in Tissues Following Focal Cerebral Ischemia  

Science Journals Connector (OSTI)

In the present study, 1,5-naphthalenediamine (1,5-DAN) hydrochloride was prepared for matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) of small molecules in liver, brain, and kidneys from mice. ... Rat brains were removed and immediately frozen under ?80 °C. ... In this study, we conducted IMS on rat brains damaged by ischemic injury and detected various phospholipids that showed unique distributions between normal and damaged areas of the brain. ...

Huihui Liu; Rui Chen; Jiyun Wang; Suming Chen; Caiqiao Xiong; Jianing Wang; Jian Hou; Qing He; Ning Zhang; Zongxiu Nie; Lanqun Mao

2014-09-23T23:59:59.000Z

91

Thermal Decomposition Mechanism of Disilane  

Science Journals Connector (OSTI)

Thermal Decomposition Mechanism of Disilane ... Thermal decomposition of disilane was investigated using time-of-flight (TOF) mass spectrometry coupled with vacuum ultraviolet single-photon ionization (VUV-SPI) at a temperature range of 675?740 K and total pressure of 20?40 Torr. ... Concentrations of disilane and trisilane during thermal decomposition of disilane were quantitatively measured using the VUV-SPI method. ...

Kazumasa Yoshida; Keiji Matsumoto; Tatsuo Oguchi; Kenichi Tonokura; Mitsuo Koshi

2006-03-18T23:59:59.000Z

92

Laser Ablation Sampling of Materials Directly into the Formed Liquid Microjunction of a Continuous Flow Surface Sampling Probe/Electrospray Ionization Emitter for Mass Spectral Analysis and Imaging  

SciTech Connect

Transmission geometry laser ablation directly into a formed liquid microjunction of a continuous flow liquid microjunction surface sampling probe/electrospray ionization emitter was utilized for molecular and elemental detection and mass spectrometry imaging. The ability to efficiently capture and ionize ablated material was demonstrated by the detection of various small soluble n-mers of polyaniline and silver ion solvent clusters formed from laser ablation of electropolymerized polyaniline and silver thin films, respectively. In addition, analysis of surfaces that contain soluble components was accomplished by coating or laminating the sample with an insoluble film to enable liquid junction formation without directly extracting material from the surface. The ability to perform mass spectrometry imaging at a spatial resolution of about 50 m was illustrated by using laminated inked patterns on a microscope slide. In general, these data demonstrate at least an order of magnitude signal enhancement compared to the non-contact, laser ablation droplet capture-based surface sampling/ionization approaches that have been previously presented.

Ovchinnikova, Olga S [ORNL] [ORNL; Lorenz, Matthias [ORNL] [ORNL; Kertesz, Vilmos [ORNL] [ORNL; Van Berkel, Gary J [ORNL] [ORNL

2013-01-01T23:59:59.000Z

93

An evaluation of robust controls for passive building thermal mass and mechanical thermal energy storage under uncertainty  

Science Journals Connector (OSTI)

Abstract Passive building thermal mass and mechanical thermal energy storage (TES) are known as one of state-of-the-art demand-side control instruments. Specifically, Model-based Predictive Control (MPC) for this operation has the potential to significantly increase performance and bring economic advantages. However, due to the uncertainty in certain operating conditions in the field, its control effectiveness could be diminished and/or seriously damaged, which results in poor performance. This study pursues improvements of the control performance of both thermal inventories under uncertainty by proposing a robust MPC in which relevant uncertainty sources are compiled; therefore, it is designed to perform more stable than traditional \\{MPCs\\} under uncertain conditions. Uniqueness and superiority of the proposed robust demand-side controls include: (i) Controls are developed based on the a priori uncertainty assessment, such that a systematic modeling approach for uncertainty was taken according to characteristics and classifications of uncertainty. (ii) The robust MPC reduces the variability of performance under varied and non-indigenous conditions compared to the deterministic MPC, and thus can avoid the worst case situation.

Sean Hay Kim

2013-01-01T23:59:59.000Z

94

Liquid Sampling-Atmospheric Pressure Glow Discharge (LS-APGD) Ionization Source for Elemental Mass Spectrometry: Preliminary Parametric Evaluation and Figures of Merit  

SciTech Connect

A new, low power ionization source for the elemental analysis of aqueous solutions has recently been described. The liquid sampling-atmospheric pressure glow discharge (LS-APGD) source operates at relatively low currents (<20 mA) and solution flow rates (<50 ?L min-1), yielding a relatively simple alternative for atomic mass spectrometry applications. The LS-APGD has been interfaced to what is otherwise an organic, LC-MS mass analyzer, the Thermo Scientific Exactive Orbitrap without any modifications; other than removing the electrospray ionization (ESI) source supplied with that instrument. A glow discharge is initiated between the surface of the test solution exiting a glass capillary and a metallic counter electrode mounted at a 90° angle and separated by a distance of ~5 mm. As with any plasma-based ionization source, there are key discharge operation and ion sampling parameters that affect the intensity and composition of the derived mass spectra; including signal-to-background ratios. We describe here a preliminary parametric evaluation of the roles of discharge current, solution flow rate, argon sheath gas flow rate, and ion sampling distance as they apply on this mass analyzer system. A cursive evaluation of potential matrix effects due to the presence of easily ionized elements (EIEs) indicate that sodium concentrations of up to 500 ?g mL-1 generally cause suppressions of less than 50%, dependant upon the analyte species. Based on the results of this series of studies, preliminary limits of detection (LOD) have been established through the generation of calibration functions. Whilst solution-based concentrations LOD levels of 0.02 – 2 ?g mL-1 3 are not impressive on the surface, the fact that they are determined via discrete 5 ?L injections leads to mass-based detection limits at picogram to singlenanogram levels. The overhead costs associated with source operation (10 W d.c. power, solution flow rates of <50 ?L min-1, and gas flow rates <10 mL min-1) are very attractive. While further optimization in the source design is suggested here, it is believed that the LS-APGD ion source may present a practical alternative to inductively-coupled plasma (ICP) sources typically employed in elemental mass spectrometry.

Quarles, C. Derrick; Carado, Anthony J.; Barinaga, Charles J.; Koppenaal, David W.; Marcus, R. Kenneth

2012-01-01T23:59:59.000Z

95

Lattice Boltzmann simulation of mass transfer in thermally driven cavity flows  

Science Journals Connector (OSTI)

We study mass transfer in 2D thermally driven cavity using lattice Boltzmann method. Simulations are performed to investigate various effects on enhancement of oxygen mass transfer in lead/lead bismuth eutectic. It is shown that oxygen transfer is dominated by convection although diffusion plays a role. Comparative studies demonstrate that side heating and top-cooling configuration is more efficient than side-heating/cooling and oxygen transfers more rapidly in a square than rectangular cavity with same area. This work supplies supportive information for developing active oxygen control technique in experiments to prevent or reduce corrosion in liquid metal cooled nuclear reactors.

Huidan Yu; Jinsuo Zhang; Ning Li

2008-01-01T23:59:59.000Z

96

Potentials of Demand Side Management Using Heat Pumps with Building Mass as a Thermal Storage  

Science Journals Connector (OSTI)

Abstract Within this work, load-shifting possibilities of heat pumps in residential buildings as well as its influencing and limiting factors are displayed. The intermediate storage is achieved by using the thermal mass of the building so the heat supply can be postponed from the heat demand for a certain period, depending on the characteristics of the building. No additional water storage is considered.

Charlotte Ellerbrok

2014-01-01T23:59:59.000Z

97

Effect of neutral collision and radiative heat-loss function on self-gravitational instability of viscous thermally conducting partially-ionized plasma  

SciTech Connect

The problem of thermal instability and gravitational instability is investigated for a partially ionized self-gravitating plasma which has connection in astrophysical condensations. We use normal mode analysis method in this problem. The general dispersion relation is derived using linearized perturbation equations of the problem. Effects of collisions with neutrals, radiative heat-loss function, viscosity, thermal conductivity and magnetic field strength, on the instability of the system are discussed. The conditions of instability are derived for a temperature-dependent and density-dependent heat-loss function with thermal conductivity. Numerical calculations have been performed to discuss the effect of various physical parameters on the growth rate of the gravitational instability. The temperature-dependent heat-loss function, thermal conductivity, viscosity, magnetic field and neutral collision have stabilizing effect, while density-dependent heat-loss function has a destabilizing effect on the growth rate of the gravitational instability. With the help of Routh-Hurwitz's criterion, the stability of the system is discussed.

Kaothekar, Sachin [School of Studies in Physics, Vikram University, Ujjain-456010, Madhya Pradesh (India); Department of Physics, Mahakal Institute of Technology, Ujjain-456664, Madhya Pradesh (India); Soni, Ghanshyam D. [Government Girls Degree College, Dewas, Madhya Pradesh (India); Chhajlani, Rajendra K. [School of Studies in Physics, Vikram University, Ujjain-456010, Madhya Pradesh (India)

2012-12-15T23:59:59.000Z

98

Scenario Analysis of Peak Demand Savings for Commercial Buildings with Thermal Mass in California  

SciTech Connect

This paper reports on the potential impact of demand response (DR) strategies in commercial buildings in California based on the Demand Response Quick Assessment Tool (DRQAT), which uses EnergyPlus simulation prototypes for office and retail buildings. The study describes the potential impact of building size, thermal mass, climate, and DR strategies on demand savings in commercial buildings. Sensitivity analyses are performed to evaluate how these factors influence the demand shift and shed during the peak period. The whole-building peak demand of a commercial building with high thermal mass in a hot climate zone can be reduced by 30percent using an optimized demand response strategy. Results are summarized for various simulation scenarios designed to help owners and managers understand the potential savings for demand response deployment. Simulated demand savings under various scenarios were compared to field-measured data in numerous climate zones, allowing calibration of the prototype models. The simulation results are compared to the peak demand data from the Commercial End-Use Survey for commercial buildings in California. On the economic side, a set of electricity rates are used to evaluate the impact of the DR strategies on economic savings for different thermal mass and climate conditions. Our comparison of recent simulation to field test results provides an understanding of the DR potential in commercial buildings.

Yin, Rongxin; Kiliccote, Sila; Piette, Mary Ann; Parrish, Kristen

2010-05-14T23:59:59.000Z

99

Demand Shifting with Thermal Mass in Large Commercial Buildings in a  

NLE Websites -- All DOE Office Websites (Extended Search)

Shifting with Thermal Mass in Large Commercial Buildings in a Shifting with Thermal Mass in Large Commercial Buildings in a California Hot Climate Zone Title Demand Shifting with Thermal Mass in Large Commercial Buildings in a California Hot Climate Zone Publication Type Report LBNL Report Number LBNL-3898e Year of Publication 2009 Authors Xu, Peng, Rongxin Yin, Carrie Brown, and DongEun Kim Date Published June 2009 Publisher CEC/LBNL Keywords demand response, demand shifting (pre-cooling), DRQAT, hot climates, market sectors, office buildings, pre-cooling, technologies, testbed tools and guides, thermal mass Abstract The potential for using building thermal mass for load shifting and peak energy demand reduction has been demonstrated in a number of simulation, laboratory, and field studies. Previous Lawrence Berkeley National Laboratory research has demonstrated that the approach is very effective in cool and moderately warm climate conditions (California Climate Zones 2-4). However, this method had not been tested in hotter climate zones.This project studied the potential of pre-cooling the building early in the morning and increasing temperature setpoints during peak hours to reduce cooling-related demand in two typical office buildings in hotter California climates - one in Visalia (CEC Climate Zone 13) and the other in San Bernardino (CEC Climate Zone 10). The conclusion of the work to date is that pre-cooling in hotter climates has similar potential to that seen previously in cool and moderate climates. All other factors being equal, results to date indicate that pre-cooling increases the depth (kW) and duration (kWh) of the possible demand shed of a given building. The effectiveness of night pre-cooling in typical office building under hot weather conditions is very limited. However, night pre-cooling is helpful for office buildings with an undersized HVAC system. Further work is required to duplicate the tests in other typical buildings and in other hot climate zones and prove that pre-cooling is truly effective.

100

Real-Time Quantitative Analysis of Combustion-Generated Polycyclic Aromatic Hydrocarbons by Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry  

Science Journals Connector (OSTI)

Real-Time Quantitative Analysis of Combustion-Generated Polycyclic Aromatic Hydrocarbons by Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry ... Field data1 suggest that naphthalene, fluorene, and anthracene are among the most abundant PAH products of incomplete hydrocarbon production. ... The sample transfer line is 6.35 mm diameter, quartz-lined stainless steel tubing (Alltech, Deerfield, IL) that is heated to 250?300 °C using flexible cable heaters (Omega Engineering, Stamford, CT). Care is taken to uniformly heat the sample transfer line, since the efficiency of the line is reduced dramatically by the presence of cold spots. ...

Christopher M. Gittins; Marco J. Castaldi; Selim M. Senkan; Eric A. Rohlfing

1997-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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
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101

Development of New Soft Ionization Mass Spectrometry Approaches for Spatial Imaging of Complex Chemical and Biological Systems  

E-Print Network (OSTI)

world's first C60 SIMS FT-ICR MS. Unique capabilities for imaging biological samples: High mass accuracy spatial resolution (~10 µm) High spatial and mass resolution C60 secondary ion mass spectrometry (SIMS of the colony Conducted first multimodal imaging of biological materials using nano-DESI, SIMS, and matrix

102

Bio-oil Analysis Using Negative Electrospray Ionization: Comparative Study of High-Resolution Mass Spectrometers and Phenolic versus Sugaric Components  

SciTech Connect

We have previously demonstrated that a petroleomic analysis could be performed for bio-oils and revealed the complex nature of bio-oils for the nonvolatile phenolic compounds (Smith, E.; Lee, Y. J. Energy Fuels 2010, 24, 5190?5198). As a subsequent study, we have adapted electrospray ionization in negative-ion mode to characterize a wide variety of bio-oil compounds. A comparative study of three common high-resolution mass spectrometers was performed to validate the methodology and to investigate the differences in mass discrimination and resolution. The mass spectrum is dominated by low mass compounds with m/z of 100–250, with some compounds being analyzable by gas chromatography–mass spectrometry (GC–MS). We could characterize over 800 chemical compositions, with only about 40 of them being previously known in GC–MS. This unveiled a much more complex nature of bio-oils than typically shown by GC–MS. The pyrolysis products of cellulose and hemicellulose, particularly polyhydroxy cyclic hydrocarbons (or what we call “sugaric” compounds), such as levoglucosan, could be effectively characterized with this approach. Phenolic compounds from lignin pyrolysis could be clearly distinguished in a contour map of double bond equivalent (DBE) versus the number of carbons from these sugaric compounds.

Smith, Erica A.; Park, Soojin; Klein, Adam T.; Lee, Young Jin

2012-05-16T23:59:59.000Z

103

Scenario Analysis of Peak Demand Savings for Commercial Buildings with Thermal Mass in California  

E-Print Network (OSTI)

by utilizing thermal energy storage such as ice storage orThermal Storage Utilization. ” Journal of Solar Energy

Yin, Rongxin

2010-01-01T23:59:59.000Z

104

Atomistic Simulations of Mass and Thermal Transport in Oxide Nuclear Fuels  

SciTech Connect

In this talk we discuss simulations of the mass and thermal transport in oxide nuclear fuels. Redistribution of fission gases such as Xe is closely coupled to nuclear fuel performance. Most fission gases have low solubility in the fuel matrix, specifically the insolubility is most pronounced for large fission gas atoms such as Xe, and as a result there is a significant driving force for segregation of gas atoms to grain boundaries or dislocations and subsequently for nucleation of gas bubbles at these sinks. The first step of the fission gas redistribution is diffusion of individual gas atoms through the fuel matrix to existing sinks, which is governed by the activation energy for bulk diffusion. Fission gas bubbles are then formed by either separate nucleation events or by filling voids that were nucleated at a prior stage; in both cases their formation and latter growth is coupled to vacancy dynamics and thus linked to the production of vacancies via irradiation or thermal events. In order to better understand bulk Xe behavior (diffusion mechanisms) in UO{sub 2{+-}x} we first calculate the relevant activation energies using density functional theory (DFT) techniques. By analyzing a combination of Xe solution thermodynamics, migration barriers and the interaction of dissolved Xe atoms with U, we demonstrate that Xe diffusion predominantly occurs via a vacancy-mediated mechanism, though other alternatives may exist in high irradiation fields. Since Xe transport is closely related to diffusion of U vacancies, we have also studied the activation energy for this process. In order to explain the low value of 2.4 eV found for U migration from independent damage experiments (not thermal equilibrium) the presence of vacancy clusters must be included in the analysis. Next a continuum transport model for Xe and U is formulated based on the diffusion mechanisms established from DFT. After combining this model with descriptions of the interaction between Xe and grain boundaries derived from separate atomistic calculations, we simulate Xe redistribution for a few simple microstructures using finite element methods (FEM), as implemented in the MOOSE framework from Idaho National Laboratory. Thermal transport together with the power distribution determines the temperature distribution in the fuel rod and it is thus one of the most influential properties on nuclear fuel performance. The fuel thermal conductivity changes as function of time due to microstructure evolution (e.g. fission gas redistribution) and compositional changes. Using molecular dynamics simulations we have studied the impact of different types of grain boundaries and fission gas bubbles on UO{sub 2} thermal conductivity.

Andersson, Anders D. [Los Alamos National Laboratory; Uberuaga, Blas P. [Los Alamos National Laboratory; Du, Shiyu [Los Alamos National Laboratory; Liu, Xiang-Yang [Los Alamos National Laboratory; Nerikar, Pankaj [IBM; Stanek, Christopher R. [Los Alamos National Laboratory; Tonks, Michael [Idaho National Laboratory; Millet, Paul [Idaho National Laboratory; Biner, Bulent [Idaho National Laboratory

2012-06-04T23:59:59.000Z

105

Quantitation by Gas Chromatography-Chemical Ionization-Mass Spectrometry of Phenylalanine Mustard in Plasma of Patients  

Science Journals Connector (OSTI)

...1980 research-article Quantification by Gas Chromatography of N,N-Di-(2-chloroethyl...addressed. A sensitive method, based on gas chromatography using a phosphorus-specific...derivatization process has been elucidated using gas chromatography-electron impact mass spectrometry...

Sharon L. Pallante; Catherine Fenselau; Robert G. Mennel; Robert B. Brundrett; Mark Appler; Neil B. Rosenshein; Michael Colvin

1980-07-01T23:59:59.000Z

106

Dustbuster: a compact impact-ionization time-of-flight mass spectrometer for in situ analysis of cosmic dust  

E-Print Network (OSTI)

a large target area with a reflectron, simultaneously optimizing mass resolution, particle detection. The resulting ions, with broad energy and angular distributions, are accelerated through a modified reflectron remote sensing, collection and analysis of dust grains that have survived impact on the Earth, capture

Stewart, Sarah T.

107

Scenario Analysis of Peak Demand Savings for Commercial Buildings with Thermal Mass in California  

NLE Websites -- All DOE Office Websites (Extended Search)

36E 36E Scenario Analysis of Peak Demand Savings for Commercial Buildings with Thermal Mass in California R. Yin, S. Kiliccote, M.A. Piette, K. Parrish Environmental Energy Technologies Division May 2010 Presented at the 2010 ACEEE Summer Study on Energy Efficiency in Buildings, Pacific Grove, CA, August 15-20, 2010, and published in the Proceedings DISCLAIMER This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor The Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information,

108

Determination of boron isotopic variations in aquatic systems with negative thermal ionization mass spectrometry as a tracer for anthropogenic influences  

Science Journals Connector (OSTI)

A technique for precise boron isotope ratio measurements with a high detection power ... –0.3% have been obtained for the determination of the 11B/10B isotope ratio using nanogram amounts of boron. Ba(OH)2 has be...

S. Eisenhut; K. G. Heumann; A. Vengosh

1996-03-01T23:59:59.000Z

109

Poly(3,4-ethylenedioxypyrrole) Modified Emitter Electrode for Substitution of Homogeneous Redox Buffer Agent Hydroquinone in Electrospray Ionization Mass Spectrometry  

SciTech Connect

The electrolysis inherent to the operation of the electrospray ionization (ESI) source used with mass spectrometry (MS) is a well-known attendant effect of generating unipolar spray droplets and may affect the analysis of the analyte of interest. Undesirable electrolysis of an analyte may be prevented by limiting the emitter electrode current and/or the mass transport characteristics of the system. However, these ways to avoid analyte electrolysis may not be applcable in all ESI-MS experiments. For example, in the case of specific nanospray systems (e.g. the wire-in-a-capillary bulk-loaded or chip-based tip-loaded nanospray configurations), the solution flow rate is fixed in the 50-500 nL/min range and the electrode surface to volume ratio is large presenting a very effcient analyte to electrode mass transport configuration. In these situations, control over the interfacial potential of the working electrode via homogeneous or traditional heterogeneous (sacrificial metal) redox buffering is a possible way to prevent analyte electrolysis. However, byproducts of these redox buffering approaches can appear in the mass spectra and/or they can chemically alter the analyte. For example, the main reason for using hydroquinone as a homogeneous redox buffer, in addition to its relatively low oxidation potential, is that neither the original compound nor its oxidation product benzoquinone can be detected directly by ESI-MS. However, benzoquinone can alter analytes with thiol functional groups by reacting with those groups via a 1,4-Michael addition.

Peintler-Krivan, Emese [ORNL; Van Berkel, Gary J [ORNL; Kertesz, Vilmos [ORNL

2010-01-01T23:59:59.000Z

110

Phase structure of thermal lattice QCD with N{sub f}=2 twisted mass Wilson fermions  

SciTech Connect

We present numerical results for the phase diagram of lattice QCD at finite temperature in the formulation with twisted mass Wilson fermions and a tree-level Symanzik-improved gauge action. Our simulations are performed on lattices with temporal extent N{sub {tau}}=8, and lattice coupling {beta} ranging from strong coupling to the scaling domain. Covering a wide range in the space spanned by the lattice coupling {beta} and the hopping and twisted mass parameters {kappa} and {mu}, respectively, we obtain a comprehensive picture of the rich phase structure of the lattice theory. In particular, we verify the existence of an Aoki phase in the strong coupling region and the realization of the Sharpe-Singleton scenario at intermediate couplings. In the weak coupling region we identify the phase boundary for the physical finite temperature phase transition/crossover. Its shape in the three-dimensional parameter space is consistent with Creutz's conjecture of a cone-shaped thermal transition surface.

Ilgenfritz, E.-M. [Institut fuer Physik, Humboldt-Universitaet zu Berlin, D-12489 Berlin (Germany); Institut fuer Theoretische Physik, Universitaet Heidelberg, D-69120 Heidelberg (Germany); Jansen, K. [DESY, Zeuthen, D-15738 Zeuthen (Germany); Lombardo, M. P. [Laboratori Nazionali di Frascati, INFN, I-100044 Frascati (RM) (Italy); Mueller-Preussker, M.; Petschlies, M. [Institut fuer Physik, Humboldt-Universitaet zu Berlin, D-12489 Berlin (Germany); Philipsen, O.; Zeidlewicz, L. [Institut fuer Theoretische Physik, Westfaelische Wilhelms-Universitaet Muenster, D-48149 Muenster (Germany)

2009-11-01T23:59:59.000Z

111

Facilities: NHMFL 9.4 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometer Citation: Characterization of Pine Pellet and Peanut Hull Pyrolysis of Bio-Oils by Negative-Ion Electrospray Ionization Fourier  

E-Print Network (OSTI)

with greater than 1% relative abundance in either phase are shown. Pyrolysis of solid biomass, in this case: Characterization of Pine Pellet and Peanut Hull Pyrolysis of Bio-Oils by Negative-Ion Electrospray Ionization of nitrogen-containing species identified in the peanut hull pyrolysis oil by FT-ICR mass spectrometry

Weston, Ken

112

Novel -Distonic Radical Cations [CnH2n+2S]+ (n ) 2, 3) Formed upon Decarbonylation of Ionized S-Alkyl Thioformates: A Mass Spectrometric and ab Initio Study  

E-Print Network (OSTI)

ions. Strong evidence for the distonic nature of the fragment ions derived from 2-7·+ has been obtained to intense peaks corresponding to H2S·+ and ionized olefins. Portions of the potential energy surface related explored in the gas phase by a variety of mass spectral methods.2,3 In particular, the -distonic isomer

Nguyen, Minh Tho

113

RELATION BETWEEN THE CORONAL MASS EJECTION ACCELERATION AND THE NON-THERMAL FLARE CHARACTERISTICS  

SciTech Connect

We investigate the relationship between the main acceleration phase of coronal mass ejections (CMEs) and the particle acceleration in the associated flares as evidenced in Reuven Ramaty High Energy Solar Spectroscopic Imager non-thermal X-rays for a set of 37 impulsive flare-CME events. Both the CME peak velocity and peak acceleration yield distinct correlations with various parameters characterizing the flare-accelerated electron spectra. The highest correlation coefficient is obtained for the relation of the CME peak velocity and the total energy in accelerated electrons (c = 0.85), supporting the idea that the acceleration of the CME and the particle acceleration in the associated flare draw their energy from a common source, probably magnetic reconnection in the current sheet behind the erupting structure. In general, the CME peak velocity shows somewhat higher correlations with the non-thermal flare parameters than the CME peak acceleration, except for the spectral index of the accelerated electron spectrum, which yields a higher correlation with the CME peak acceleration (c Almost-Equal-To -0.6), indicating that the hardness of the flare-accelerated electron spectrum is tightly coupled to the impulsive acceleration process of the rising CME structure. We also obtained high correlations between the CME initiation height h{sub 0} and the non-thermal flare parameters, with the highest correlation of h{sub 0} to the spectral index {delta} of flare-accelerated electrons (c Almost-Equal-To 0.8). This means that CMEs erupting at low coronal heights, i.e., in regions of stronger magnetic fields, are accompanied by flares that are more efficient at accelerating electrons to high energies. In the majority of events ({approx}80%), the non-thermal flare emission starts after the CME acceleration, on average delayed by Almost-Equal-To 6 minutes, in line with the standard flare model where the rising flux rope stretches the field lines underneath until magnetic reconnection sets in. We find that the current sheet length at the onset of magnetic reconnection is 21 {+-} 7 Mm. The flare hard X-ray peaks are well synchronized with the peak of the CME acceleration profile, and in 75% of the cases they occur within {+-}5 minutes. Our findings provide strong evidence for the tight coupling between the CME dynamics and the particle acceleration in the associated flare in impulsive events, with the total energy in accelerated electrons being closely correlated with the peak velocity (and thus the kinetic energy) of the CME, whereas the number of electrons accelerated to high energies is decisively related to the CME peak acceleration and the height of the pre-eruptive structure.

Berkebile-Stoiser, S.; Veronig, A. M.; Bein, B. M.; Temmer, M., E-mail: asv@igam.uni-graz.at [Institute of Physics, University of Graz, A-8010 Graz (Austria)

2012-07-01T23:59:59.000Z

114

Confirmatory analysis of ethylglucuronide in urine by liquid-chromatography/electrospray ionization/tandem mass spectrometry according to forensic guidelines  

Science Journals Connector (OSTI)

?-D-ethylglucuronide (EtG) is a stable Phase II metabolite of ethanol which can be detected in urine samples several days after elimination of ethanol. It is a useful diagnostic parameter for monitoring abstinence of alcoholics in alcohol withdrawal treatment. For this purpose, determination in urine is mainly performed by LC-MS, LC-MS/MS, or by GC-MS. For the mass spectrometric identification and detection of controlled substances in more sensitive fields such as forensic toxicology, workplace drug testing, doping analysis, and veterinary organic residue control, official guidelines have been released requiring a chromatographic separation and a minimum of two mass spectrometric transitions of the analyte. However, for detection of EtG none of the published LC-MS/MS methods could fulfill the minimum requirements of any of these guidelines. Therefore, an existing LC-MS/MS method has been modified by monitoring further MS/MS transitions instead of only one (deprotonated molecule [M ? H]?/product ions: m/z 75, 85, 113, and 159 optional) with the aim of withstanding administrative or court scrutiny in forensic or workplace drug testing cases. Full method validation has been performed in accordance to guidelines of the German Society of Toxicology and Forensic Chemistry (GTFCh) and requirements of ISO 17025. One application field in the United States is a workplace monitoring program to detect surreptitious alcohol use among recovering health professionals, who by contract had agreed on total abstinence after drug and alcohol withdrawal therapy.

Wolfgang Weinmann; Patrick Schaefer; Annette Thierauf; André Schreiber; Friedrich Martin Wurst

2004-01-01T23:59:59.000Z

115

Simultaneous determination of nine trace mono- and di-chlorophenols in water by ion chromatography atmospheric pressure chemical ionization mass spectrometry  

Science Journals Connector (OSTI)

A novel analytical method was proposed for the rapidly simultaneous determination of nine mono-chlorophenols (MCPs) and di-chlorophenols (DCPs) in water samples using eluent generator ion chromatography (IC) coupled with an atmospheric pressure chemical ionization mass spectrometry (APCI-MS) in the negative mode. The IC separation was carried out on an IonPac® AS11 analytical column (250 mm × 4.0 mm) using gradient KOH containing 15% acetonitrile as organic modifier at a constant flow rate of 1.0 mL/min. The molecular ions m/z [M ? H]? 127 and 161 were selected for the quantification in selected ion monitoring (SIM) mode for \\{MCPs\\} and DCPs, respectively. The average recoveries were between 80.6% and 92.6%. Within-day and day-to-day relative standard deviations were less than 12.1% and 13.3%, respectively. The method allowed the nine objective compounds in water samples to be determined at ?g/L levels. It was confirmed that this method could be used in routine analysis.

Micong Jin; Yiwen Yang

2006-01-01T23:59:59.000Z

116

(Resonance ionization spectroscopy)  

SciTech Connect

J. P. Young attended the Fifth International Symposium on Resonance Ionization Spectroscopy and presented an invited oral presentation on research he and coworkers had carried out in applying diode lasers to resonance ionization mass spectrometry. A summary of the conference is given along with an assessment of some of the presentations that the author found of interest. Young also visited Professor Marassi at the University of Camerino to present a seminar and discuss mutual interests in a new molten salt research project of the author. Some of the studies at Camerino are described. Ideas concerning the author's research that came from private discussions are also presented here.

Young, J.P.

1990-10-11T23:59:59.000Z

117

Ionization chamber  

DOE Patents (OSTI)

An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

Walenta, Albert H. (Port Jefferson Station, NY)

1981-01-01T23:59:59.000Z

118

Detailed Analysis of the Thermal Mass Credits in a Code-Traceable DOE-2 Simulation of the 2001 IECC for a Single-Family Residence in Texas  

E-Print Network (OSTI)

This paper presents the results of a study that investigates the thermal mass credits in the 2001 International Energy Conservation Code (IECC) (ICC 1999, 2001) for a single-family residence in Texas using the DOE-2 building energy simulation...

Kim, S.; Haberl, J.

119

A Validated Liquid Chromatography-Atmospheric Pressure Chemical Ionization-Tandem Mass Spectrometry Method for Quantitation of Cocaine and Benzoylecgonine in Human Plasma  

Science Journals Connector (OSTI)

......Chromatography-Atmospheric Pressure Chemical...Benzoylecgonine in Human Plasma Shen-Nan Lin 1...chromatography-atmospheric pressure chemical...benzoylecgonine in human plasma. | In order to...ValidatedLiquidChromatography-Atmospheric PressureChemicalIonization...benzoylecgonine in human plasma.Cocaine-dsand......

Shen-Nan Lin; David E. Moody; George E. Bigelow; Rodger L. Foltz

2001-10-01T23:59:59.000Z

120

Sample Desorption/Ionization From Mesoporous Silica  

NLE Websites -- All DOE Office Websites (Extended Search)

Sample Desorption/Ionization From Mesoporous Silica Sample Desorption/Ionization From Mesoporous Silica Sample Desorption/Ionization From Mesoporous Silica Mesoporous silica is shown to be a sample holder for laser desorption/ionization of mass spectrometry. Available for thumbnail of Feynman Center (505) 665-9090 Email Sample Desorption/Ionization From Mesoporous Silica Mesoporous silica is shown to be a sample holder for laser desorption/ionization of mass spectrometry. Supported mesoporous silica was prepared by coating an ethanolic silicate solution having a removable surfactant onto a substrate to produce a self-assembled, ordered, nanocomposite silica thin film. The surfactant was chosen to provide a desired pore size between about 1 nanometer diameter and 50 nanometers diameter. Removal of the surfactant resulted in a mesoporous silica thin

Note: This page contains sample records for the topic "thermal ionization mass" 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

Optical and Mass Spectrometric Studies of a Helium Dielectric-Barrier Atmospheric-Pressure Plasma Jet Used as an Ambient Desorption Ionization Source.  

E-Print Network (OSTI)

??Recently there has been a surge in the field of mass spectrometry centered around the concept of rapid analysis of target analytes with minimal or… (more)

Heywood, Matthew Spencer

2012-01-01T23:59:59.000Z

122

Phenotypic Detection of Carbapenemase-Producing Enterobacteriaceae by Use of Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry and the Carba NP Test  

Science Journals Connector (OSTI)

...Flight Mass Spectrometry and the Carba NP Test James Knox a Snehal Jadhav b Danielle Sevior...the diagnostic accuracy of the Carba NP test with that of a straightforward matrix-assisted...Using PCR as the reference method, both tests demonstrated a sensitivity of 87% and...

James Knox; Snehal Jadhav; Danielle Sevior; Alex Agyekum; Margaret Whipp; Lynette Waring; Jonathan Iredell; Enzo Palombo

2014-09-03T23:59:59.000Z

123

Heat and Mass Transfer in a Wetted Thermal Insulation of hot Water Pipes Operating Under Flooding Conditions  

Science Journals Connector (OSTI)

We present the results of numerical simulation of the thermal regimes of hot water pipes under flooding conditions with account for evaporation and diffusion ... modeling thermal regimes of hot water pipes under

V. Yu. Polovnikov; E. V. Gubina

2014-09-01T23:59:59.000Z

124

Investigating Enhanced Thorium Ionization in TIMS Using Re/Pt Porous Ion Emitters  

SciTech Connect

Thermal ionization mass spectrometry (TIMS) is a widely used, benchmark method in the isotopic analysis of actinides relevant to various nuclear and geological fields. Despite significant previous use and inherent advantages, however, poor sample ionization continues to hamper the use of TIMS in the measurement of trace species; actinide ionization efficiencies frequently fall below 0.1 % using traditional instrument sources. Factors leading to poor ionization are compounded in the measurement of several highly refractory metals (e.g. U and Th) that may provide key signatures data in non-proliferation, safeguards and forensics efforts. Herein, a relatively new TIMS ion source strategy, employing porous ion emitters (PIEs) atop traditional filament assemblies, is investigated for the first time as a straightforward means of enhancing the ionization of Th, which is arguably a worst case scenario for TIMS-based actinide measurements. These sources yielded up to 410% greater Th sample utilization, relative to previously published values and in-house measurements collected using traditional methods. Accompanying scanning electron microscopy (SEM) investigations provide preliminary insight into possible mechanisms of PIE functioning and explore the impacts that extended heating have on the constructed source’s structure and composition.

Floyd E. Stanley III; K. J. Spencer; D. S. Schwartz; M. G. Watrous; J. E. Delmore

2014-03-01T23:59:59.000Z

125

Solid-Phase Extraction Combined with High-Performance Liquid Chromatography?Atmospheric Pressure Chemical Ionization?Mass Spectrometry Analysis of Pesticides in Water:? Method Performance and Application in a Reconnaissance Survey of Residues in Drinking Water in Greater Cairo, Egypt  

Science Journals Connector (OSTI)

Solid-Phase Extraction Combined with High-Performance Liquid Chromatography?Atmospheric Pressure Chemical Ionization?Mass Spectrometry Analysis of Pesticides in Water:? Method Performance and Application in a Reconnaissance Survey of Residues in Drinking Water in Greater Cairo, Egypt ... Each shipment, which included 24 cartridges, weighed <454 g and cost approximately 200 Egyptian pounds ($40 U.S.). ...

Thomas L. Potter; Mahmoud A. Mohamed; Hannah Ali

2006-12-22T23:59:59.000Z

126

Development of matrix assisted laser desorption ionization-ion mobility-orthogonal time-of-flight mass spectrometry as a tool for proteomics  

E-Print Network (OSTI)

trend line, it is possible to include peptide masses obtained from lower intensity ion signals in a database search at a higher level of confidence, thus obtaining higher percent protein coverage and higher confidence-level protein identification.7... line correlation data in combination with database search results that found no match for m/z 1880 or 2380 (at 2 missed cleavage) was used to tentatively identify the two signals as 14-25+heme and 8-22+heme respectfully, where no such identification...

Ruotolo, Brandon Thomas

2005-08-29T23:59:59.000Z

127

Airfoil sampling of a pulsed Laval beam with tunable vacuum ultraviolet (VUV) synchrotron ionization quadrupole mass spectrometry: Application to low--temperature kinetics and product detection  

SciTech Connect

A new pulsed Laval nozzle apparatus with vacuum ultraviolet (VUV) synchrotron photoionization quadrupole mass spectrometry is constructed to study low-temperature radicalneutralchemical reactions of importance for modeling the atmosphere of Titan and the outer planets. A design for the sampling geometry of a pulsed Laval nozzle expansion has beendeveloped that operates successfully for the determination of rate coefficients by time-resolved mass spectrometry. The new concept employs airfoil sampling of the collimated expansion withexcellent sampling throughput. Time-resolved profiles of the high Mach number gas flow obtained by photoionization signals show that perturbation of the collimated expansion by theairfoil is negligible. The reaction of C2H with C2H2 is studied at 70 K as a proof-of-principle result for both low-temperature rate coefficient measurements and product identification basedon the photoionization spectrum of the reaction product versus VUV photon energy. This approach can be used to provide new insights into reaction mechanisms occurring at kinetic ratesclose to the collision-determined limit.

Soorkia, Satchin; Liu, Chen-Lin; Savee, John D.; Ferrell, Sarah J.; Leone, Stephen R.; Wilson, Kevin R.

2011-10-12T23:59:59.000Z

128

NON-EQUILIBRIUM IONIZATION MODELING OF THE CURRENT SHEET IN A SIMULATED SOLAR ERUPTION  

SciTech Connect

The current sheet that extends from the top of flare loops and connects to an associated flux rope is a common structure in models of coronal mass ejections (CMEs). To understand the observational properties of CME current sheets, we generated predictions from a flare/CME model to be compared with observations. We use a simulation of a large-scale CME current sheet previously reported by Reeves et al. This simulation includes ohmic and coronal heating, thermal conduction, and radiative cooling in the energy equation. Using the results of this simulation, we perform time-dependent ionization calculations of the flow in a CME current sheet and construct two-dimensional spatial distributions of ionic charge states for multiple chemical elements. We use the filter responses from the Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory and the predicted intensities of emission lines to compute the count rates for each of the AIA bands. The results show differences in the emission line intensities between equilibrium and non-equilibrium ionization. The current sheet plasma is underionized at low heights and overionized at large heights. At low heights in the current sheet, the intensities of the AIA 94 A and 131 A channels are lower for non-equilibrium ionization than for equilibrium ionization. At large heights, these intensities are higher for non-equilibrium ionization than for equilibrium ionization inside the current sheet. The assumption of ionization equilibrium would lead to a significant underestimate of the temperature low in the current sheet and overestimate at larger heights. We also calculate the intensities of ultraviolet lines and predict emission features to be compared with events from the Ultraviolet Coronagraph Spectrometer on the Solar and Heliospheric Observatory, including a low-intensity region around the current sheet corresponding to this model.

Shen Chengcai; Reeves, Katharine K.; Raymond, John C.; Murphy, Nicholas A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Ko, Yuan-Kuen [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Lin Jun [Yunnan Astronomical Observatory, Chinese Academy of Sciences, P. O. Box 110, Kunming, Yunnan 650011 (China); Mikic, Zoran; Linker, Jon A. [Predictive Science, Inc. (PSI), San Diego, CA 92121-2910 (United States)

2013-08-20T23:59:59.000Z

129

Liquid Microjunction Surface Sampling Coupled with High-Pressure Liquid Chromatography-Electrospray Ionization-Mass Spectrometry for Analysis of Drugs and Metabolites in Whole-Body Thin Tissue Sections  

SciTech Connect

In this work, a commercially available autosampler was adapted to perform direct liquid microjunction (LMJ) surface sampling followed by a high-pressure liquid chromatography (HPLC) separation of the extract components and detection with electrospray ionization mass spectrometry (ESI-MS). To illustrate the utility of coupling a separation with this direct liquid extraction based surface sampling approach, four different organs (brain, lung, kidney, and liver) from whole-body thin tissue sections of propranolol dosed and control mice were examined. The parent drug was observed in the chromatograms of the surface sampling extracts from all the organs of the dosed mouse examined. In addition, two isomeric phase II metabolites of propranolol (an aliphatic and an aromatic hydroxypropranolol glucuronide) were observed in the chromatograms of the extracts from lung, kidney, and liver. Confirming the presence of one or the other or both of these glucuronides in the extract from the various organs was not possible without the separation. These drug and metabolite data obtained using the LMJ surface sampling/HPLC-MS method and the results achieved by analyzing similar samples by conventional extraction of the tissues and subsequent HPLC-MS analysis were consistent.

Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2010-01-01T23:59:59.000Z

130

Thermal Decomposition of Molecules Relevant to Combustion and Chemical Vapor Deposition by Flash Pyrolysis Time-of-Flight Mass Spectrometry  

E-Print Network (OSTI)

of Small Molecules by Flash Pyrolysis, University ofwas performed using flash pyrolysis vacuum-ultraviolet time-Vapor Deposition by Flash Pyrolysis Time-of-Flight Mass

Lemieux, Jessy Mario

2013-01-01T23:59:59.000Z

131

Electron impact study of ionization and dissociation of monosilane and disilane  

Science Journals Connector (OSTI)

Electron impact study of ionization and dissociation of monosilane and disilane ... Formation Mechanism of Hydrogenated Silicon Clusters during Thermal Decomposition of Disilane ... Formation Mechanism of Hydrogenated Silicon Clusters during Thermal Decomposition of Disilane ...

P. Potzinger; F. W. Lampe

1969-01-01T23:59:59.000Z

132

A semi-analytical model for heat and mass transfer in geothermal reservoirs to estimate fracture surface-are-to-volume ratios and thermal breakthrough using thermally-decaying and diffusing tracers  

SciTech Connect

A semi-analytical model was developed to conduct rapid scoping calculations of responses of thermally degrading and diffusing tracers in multi-well tracer tests in enhanced geothermal systems (EGS). The model is based on an existing Laplace transform inversion model for solute transport in dual-porosity media. The heat- and mass-transfer calculations are decoupled and conducted sequentially, taking advantage of the fact that heat transfer between fractures and the rock matrix is much more rapid than mass transfer and therefore mass transfer will effectively occur in a locally isothermal system (although the system will be nonisothermal along fracture flow pathways, which is accounted for by discretizing the flow pathways into multiple segments that have different temperature histories). The model takes advantage of the analogies between heat and mass transfer, solving the same governing equations with k{sub m}/({rho}C{sub p}){sub w} being substituted for {phi}D{sub m} in the equation for fracture transport and k{sub m}/({rho}C{sub p}){sub m} being subsituted for D{sub m} in the equation for matrix transport; where k = thermal conductivity (cal/cm-s-K), {rho} = density (g/cm{sup 3}), C{sub p} = heat capacity (at constant pressure) (cal/g-K), {phi} = matrix porosity, and D = tracer diffusion coefficient (cm{sup 2}/s), with the subscripts w and m referring to water and matrix, respectively. A significant advantage of the model is that it executes in a fraction of second on a single-CPU personal computer, making it very amenable for parameter estimation algorithms that involve repeated runs to find global minima. The combined thermal-mass transport model was used to evaluate the ability to estimate when thermal breakthrough would occur in a multi-well EGS configuration using thermally degrading tracers. Calculations were conducted to evaluate the range of values of Arrhenius parameters, A and E{sub {alpha}} (pre-exponential factor, 1/s, and activation energy, cal/mol) required to obtain interpretable responses of thermally-degrading tracers that decay according to the rate constant k{sub d} = Ae{sup -E{sub {alpha}}/RT}, where k{sub d} = decay rate constant (1/s), R = ideal gas constant (1.987 cal/mol-K), and T = absolute temperature (K). It is shown that there are relatively narrow ranges of A and E{sub {alpha}} that will result in readily interpretable tracer responses for any given combination of ambient reservoir temperature and working fluid residence time in a reservoir. The combined model was also used to simulate the responses of conservative tracers with different diffusion coefficients as a way of estimating fracture surface-area-to-volume ratios (SA/V) in multi-well EGS systems. This method takes advantage of the fact that the differences in breakthrough curves of tracers with different matrix diffusion coefficients are a function of SA/V. The model accounts for differences in diffusion coefficients as a function of temperature so that tracer responses obtained at different times can be used to obtain consistent estimates of SA/V as the reservoir cools down. Some single-well applications of this approach are simulated with a numerical model to demonstrate the potential to evaluate the effectiveness of EGS stimulations before a second well is drilled.

Reimus, Paul W [Los Alamos National Laboratory

2010-12-08T23:59:59.000Z

133

Plasma Diagnosis from Thermal Noise and Limits on Dust Flux or Mass in Comet Giacobini-Zinner  

Science Journals Connector (OSTI)

...electrons. Thus, an ideal thermal plasma detector should have a frequency...with a receiver frequency range 30 kHz to 2 MHz: the plasma frequency and Debye length (which...m in the solar wind) were 100 kHz and 1 m at 2000 km away from the...

N. MEYER-VERNET; P. COUTURIER; S. HOANG; C. PERCHE; J. L. STEINBERG; J. FAINBERG; C. MEETRE

1986-04-18T23:59:59.000Z

134

Risks from ionizing radiation  

Science Journals Connector (OSTI)

... RADON indoors now accounts for nearly half of the average UK population exposure to ionizing radiation ... exposure to ionizing radiation. We believe that the extent of the variation in exposure to radon in the United Kingdom and else-where and its magnitude in relation to exposures from ...

R. H. Clarke; T. R. E. Southwood

1989-03-16T23:59:59.000Z

135

Identification of volatile butyl rubber thermal-oxidative degradation products by cryofocusing gas chromatography/mass spectrometry (cryo-GC/MS).  

SciTech Connect

Chemical structure and physical properties of materials, such as polymers, can be altered as aging progresses, which may result in a material that is ineffective for its envisioned intent. Butyl rubber formulations, starting material, and additives were aged under thermal-oxidative conditions for up to 413 total days at up to 124 %C2%B0C. Samples included: two formulations developed at Kansas City Plant (KCP) (%236 and %2310), one commercially available formulation (%2321), Laxness bromobutyl 2030 starting material, and two additives (polyethylene AC-617 and Vanax MBM). The low-molecular weight volatile thermal-oxidative degradation products that collected in the headspace over the samples were preconcentrated, separated, and detected using cryofocusing gas chromatography mass spectrometry (cryo-GC/MS). The majority of identified degradation species were alkanes, alkenes, alcohols, ketones, and aldehydes. Observations for Butyl %2310 aged in an oxygen-18 enriched atmosphere (18O2) were used to verify when the source of oxygen in the applicable degradation products was from the gaseous environment rather than the polymeric mixture. For comparison purposes, Butyl %2310 was also aged under non-oxidative thermal conditions using an argon atmosphere.

Smith, Jonell Nicole; White, Michael Irvin; Bernstein, Robert; Hochrein, James Michael

2013-02-01T23:59:59.000Z

136

LoCuSS: A COMPARISON OF CLUSTER MASS MEASUREMENTS FROM XMM-NEWTON AND SUBARU-TESTING DEVIATION FROM HYDROSTATIC EQUILIBRIUM AND NON-THERMAL PRESSURE SUPPORT  

SciTech Connect

We compare X-ray hydrostatic and weak-lensing mass estimates for a sample of 12 clusters that have been observed with both XMM-Newton and Subaru. At an over-density of DELTA = 500, we obtain 1 - M {sup X}/M {sup WL} = 0.01 +- 0.07 for the whole sample. We also divided the sample into undisturbed and disturbed sub-samples based on quantitative X-ray morphologies using asymmetry and fluctuation parameters, obtaining 1 - M {sup X}/M {sup WL} = 0.09 +- 0.06 and -0.06 +- 0.12 for the undisturbed and disturbed clusters, respectively. In addition to non-thermal pressure support, there may be a competing effect associated with adiabatic compression and/or shock heating which leads to overestimate of X-ray hydrostatic masses for disturbed clusters, for example, in the famous merging cluster A1914. Despite the modest statistical significance of the mass discrepancy, on average, in the undisturbed clusters, we detect a clear trend of improving agreement between M {sup X} and M {sup WL} as a function of increasing over-density, M{sup X}/M{sup WL}=(0.908+-0.004)+(0.187+-0.010){center_dot} log{sub 10}(DELTA/500). We also examine the gas mass fractions, f{sub gas} = M {sup gas}/M {sup WL}, finding that they are an increasing function of cluster radius, with no dependence on dynamical state, in agreement with predictions from numerical simulations. Overall, our results demonstrate that XMM-Newton and Subaru are a powerful combination for calibrating systematic uncertainties in cluster mass measurements.

Zhang, Yu-Ying [Argelander-Institut fuer Astronomie, Universitaet Bonn, Auf dem Huegel 71, 53121 Bonn (Germany); Okabe, Nobuhiro [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, 10617 Taipei, Taiwan (China); Finoguenov, Alexis [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, 85748 Garching (Germany); Smith, Graham P.; Sanderson, Alastair J. R. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B152TT (United Kingdom); Piffaretti, Rocco [CEA, CEA-Saclay, 91191 Gif-sur-Yvette Cedex (France); Valdarnini, Riccardo [SISSA/ISAS, via Beirut 4, 34014 Trieste (Italy); Babul, Arif [Department of Physics and Astronomy, University of Victoria, 3800 Finnerty Road, Victoria, BC (Canada); Evrard, August E. [Department of Physics and Michigan Center for Theoretical Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Mazzotta, Pasquale [Dipartimento di Fisica, Universita di Roma 'Tor Vergata', Via della Ricerca Scientifica 1, I-00133 Rome (Italy); Marrone, Daniel P., E-mail: yyzhang@astro.uni-bonn.d [Kavli Institute for Cosmological Physics, Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States)

2010-03-10T23:59:59.000Z

137

Chemical Analysis of Diesel Engine Nanoparticles Using a Nano-DMA/Thermal Desorption Particle Beam Mass Spectrometer  

Science Journals Connector (OSTI)

Modern combustion engines burn cleaner and produce less particulate mass than older models, but it has also been observed that some engines, for example, diesels, emit high number concentrations of a subset of fine particles called nanoparticles (diameter cycle, turbocharged diesel engine that produced a peak torque of 350 N-m at an intermediate engine speed of 1400 rpm, which is generally used for short-duration work periods of heavy lifting or material handling. ... However, general trends from past studies can be applied to the analysis of this work. ...

Herbert J. Tobias; Derek E. Beving; Paul J. Ziemann; Hiromu Sakurai; Miriam Zuk; Peter H. McMurry; Darrick Zarling; Robert Waytulonis; David B. Kittelson

2001-04-25T23:59:59.000Z

138

Multiphoton ionization of large water clusters  

SciTech Connect

Water clusters are multimers of water molecules held together by hydrogen bonds. In the present work, multiphoton ionization in the UV range coupled with time of flight mass spectrometry has been applied to water clusters with up to 160 molecules in order to obtain information on the electronic states of clusters of different sizes up to dimensions that can approximate the bulk phase. The dependence of ion intensities of water clusters and their metastable fragments produced by laser ionization at 355 nm on laser power density indicates a (3+1)-photon resonance-enhanced multiphoton ionization process. It also explains the large increase of ionization efficiency at 355 nm compared to that at 266 nm. Indeed, it was found, by applying both nanosecond and picosecond laser ionization with the two different UV wavelengths, that no water cluster sequences after n = 9 could be observed at 266 nm, whereas water clusters up to m/z 2000 Th in reflectron mode and m/z 3000 Th in linear mode were detected at 355 nm. The agreement between our findings on clusters of water, especially true in the range with n > 10, and reported data for liquid water supports the hypothesis that clusters above a critical dimension can approximate the liquid phase. It should thus be possible to study clusters just above 10 water molecules, for getting information on the bulk phase structure.

Apicella, B., E-mail: apicella@irc.cnr.it [Combustion Research Institute, IRC–C.N.R., P.le Tecchio 80, 80125 Napoli (Italy); Li, X. [Key Laboratory of Power Machinery and Engineering, Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240 (China); Passaro, M. [CNISM and Chemical Engineering, Materials and Industrial Production Department, University of Naples “Federico II,” P.le Tecchio 80, 80125 Napoli (Italy); Spinelli, N. [CNISM and Physics Department, University of Naples “Federico II,” Via Cintia, 80124 Napoli (Italy); Wang, X. [SPIN–C.N.R., Via Cintia, 80124 Napoli (Italy)

2014-05-28T23:59:59.000Z

139

A comprehensive range of X-ray ionized reflection models  

E-Print Network (OSTI)

X-ray ionized reflection occurs when a surface is irradiated with X-rays so intense that its ionization state is determined by the ionization parameter xi propto F/n, where F is the incident flux and n the gas density. It occurs in accretion, onto compact objects including black holes in both active galaxies and stellar-mass binaries, and possibly in gamma-ray bursts. Computation of model reflection spectra is often time-consuming. Here we present the results from a comprehensive grid of models computed with our code, which has now been extended to include what we consider to be all energetically-important ionization states and transitions. This grid is being made available as an ionized-reflection model, REFLION, for XSPEC.

R. R. Ross; A. C. Fabian

2005-01-07T23:59:59.000Z

140

A Unified Approach for the Measurement of Individual or Total Volatile Organic Sulfur Compounds in Hydrocarbon Matrices by Dual-Plasma Chemiluminescence Detector and Low Thermal Mass Gas Chromatography  

Science Journals Connector (OSTI)

......ozone (6). In the case of the DP-SCD, a quartz-based heater is enclosed in a low thermal mass metal housing to form the...61: 12681271 (1989). 7. R. Shearer. Development of flameless sulfur chemiluminescence detection: applications to gas chromatography......

Ronda Gras; Jim Luong; Randy Shearer

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141

Fission product studies in the symmetric mass region  

SciTech Connect

Fission yields can be determined by radiochemical or mass spectrometric techniques. Mass spectrometry can provide more accurate data, particularly in the symmetric mass region where the probability of fission is low and uncertainties in isometric ratios occur. Fine structure in the mass distribution can usually only be determined by mass spectrometry. Many of the elements in the valley of symmetry have high ionization potentials and are therefore difficult to measure by solid source mass spectrometry. Analytical techniques have been developed to provide the sensitivity required to measure the small sample sizes available in fission product studies. Cumulative fission yields for ruthenium, palladium, cadmium, tin, and tellurium have been measured by mass spectrometry for the thermal and epicadmium fission of {sup 233}U and for thermal and epicadmium fission of {sup 239}Pu. These fission yields, which span the mass range 101 {le} A {le} 130, can be combined to give a mass yield curve for {sup 235}U in the valley region, which is symmetrical about A = 116.8 and exhibits fine structure in the mass 113 to 114 region. Fine structure in {sup 233}U is also present at mass 111. Mass spectrometric determinations of the fission yields of uranium ore at the Oklo mine site in Gabon enable the nuclear parameters of this natural reactor to be evaluated. This in turn enables the amounts of fission products produced in the reactor zone and the surrounding rocks enables an assessment to be made of the efficiency of this geological repository for containing radioactive waste. The elemental abundances can be determined by isotope dilution mass spectrometry. Unfortunately, the paucity of good fission yield data available for {sup 238}U by fast neutrons is a severe constraint in this evaluation.

De Laeter, J.R.; Rosman, K.J.R.; Loss, R.D. [Curtin Univ. of Technology, Perth (AU)

1993-05-01T23:59:59.000Z

142

Salt Tolerance of Desorption Electrospray Ionization (DESI)  

SciTech Connect

Suppression of ion intensity in the presence of high salt matrices is common in most mass spectrometry ionization techniques. Desorption electrospray ionization (DESI) is an ionization method that exhibits salt tolerance, and this is investigated. DESI analysis was performed on three different drug mixtures in the presence of 0, 0.2, 2, 5, 10, and 20% NaCl:KCl weight by volume from seven different surfaces. At physiological concentrations individual drugs in each mixture were observed with each surface. Collision-induced dissociation (CID) was used to provide additional confirmation for select compounds. Multiple stage experiments, to MS5, were performed for select compounds. Even in the absence of added salt, the benzodiazepine containing mixture yielded sodium and potassium adducts of carbamazepine which masked the ions of interest. These adducts were eliminated by adding 0.1% 7M ammonium acetate to the standard methanol:water (1:1) spray solvent. Comparison of the salt tolerance of DESI with that of electrospray ionization (ESI) demonstrated much better signal/noise characteristics for DESI in this study. The salt tolerance of DESI was also studied by performing limit of detection and dynamic range experiments. Even at a salt concentration significantly above physiological concentrations, select surfaces were effective in providing spectra that allowed the ready identification of the compounds of interest. The already high salt tolerance of DESI can be optimized further by appropriate choices of surface and spray solution.

Jackson, Ayanna U. [Purdue University; Talaty, Nari [Purdue University; Cooks, R G [Purdue University; Van Berkel, Gary J [ORNL

2007-01-01T23:59:59.000Z

143

Thermal Desorption-Gas Chromatography or Gas Chromatography-Mass Spectrometry for Analysis of Semi-Volatile Compounds on Atmospheric Particulate Matters  

Science Journals Connector (OSTI)

Abstract A thermal desorption (TD) device was developed and coupled to gas chromatograph (GC) or gas chromatograph-mass spectrometer (GC-MS) for the qualitative and quantitative analysis of semi-volatile organic compounds on atmospheric particulate matters (PM). The TD was operated by direct heating and placed on the top of GC injector, leading to high heating rate and easy transfer of analytes to GC without re-focusing of analytes by cold trap. The materials used for supporting PM samples, desorption temperature and time, and types of sample injection were investigated for the detection of sixteen polycyclic aromatic hydrocarbons (PAHs) and nine n-alkanes. The limits of detection of the proposed TD-GC method were in the range of 0.014–0.094 ng for PAHs, and 0.016–0.026 ng for n-alkanes, with coefficients of correlation above 0.9975. The TD-GC method was applied to the determination of trace \\{PAHs\\} and n-alkanes on PM10 samples from three cities. The recoveries were in the range of 95%–135% (PAHs) and 95%–115% (n-alkanes). Finally, the TD was coupled to GC-MS for comparison of the contents of \\{PAHs\\} and n-alkanes on \\{PMx\\} with different particulate size (x = 10, 5, 2, 1, 0.5, 0.25, 0.1).

Hu MENG; Jing-Hong ZHAO; Chun-Feng DUAN; Liang HAO; Ya-Feng GUAN

2014-01-01T23:59:59.000Z

144

Hysteresis of ionization waves  

SciTech Connect

A quasi-logistic, nonlinear model for ionization wave modes is introduced. Modes are due to finite size of the discharge and current feedback. The model consists of competing coupled modes and it incorporates spatial wave amplitude saturation. The hysteresis of wave mode transitions under current variation is reproduced. Sidebands are predicted by the model and found in experimental data. The ad hoc model is equivalent to a general--so-called universal--approach from bifurcation theory.

Dinklage, A. [Max-Planck-Institut fuer Plasmaphysik, EURATOM-Association, Wendelsteinstr. 1, 17491 Greifswald (Germany); Bruhn, B.; Testrich, H. [Institut fuer Physik, E.-M.-Arndt Universitaet Greifswald, Felix-Hausdorff-Str. 6, 17487 Greifswald (Germany); Wilke, C. [Leibniz-Institut fuer Plasmaforschung und Technologie, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany)

2008-06-15T23:59:59.000Z

145

Inr .I. Heor Mass Transfer. Vol. 14. pp. 751-766. Pergamon Press 1971 Printed in Great Britain THE EFFECT OF THERMAL DISTORTION ON  

E-Print Network (OSTI)

on the thermal contact resistance between two semi-infinite solids of different materials. Good agreement THE EFFECT OF THERMAL DISTORTION ON CONSTRICTION RESISTANCE J. R. BARBER Department of Mechanical Engineering ; "9 Poisson's ratio ; P, thermal contact resistance ; 0, direct stress. Subscripts 0, interface

Barber, James R.

146

The multiphoton ionization of uranium hexafluoride  

SciTech Connect

Multiphoton ionization (MPI) time-of-flight mass spectroscopy and photoelectron spectroscopy studies of UF{sub 6} have been conducted using focused light from the Nd:YAG laser fundamental ({lambda}=1064 nm) and its harmonics ({lambda}=532, 355, or 266 nm), as well as other wavelengths provided by a tunable dye laser. The MPI mass spectra are dominated by the singly and multiply charged uranium ions rather than by the UF{sub x}{sup +} fragment ions even at the lowest laser power densities at which signal could be detected. The laser power dependence of U{sup n+} ions signals indicates that saturation can occur for many of the steps required for their ionization. In general, the doubly-charged uranium ion (U{sup 2+}) intensity is much greater than that of the singly-charged uranium ion (U{sup +}). For the case of the tunable dye laser experiments, the U{sup n+} (n = 1- 4) wavelength dependence is relatively unstructured and does not show observable resonance enhancement at known atomic uranium excitation wavelengths. The dominance of the U{sup 2+} ion and the absence or very small intensities of UF{sub x}{sup +} fragments, along with the unsaturated wavelength dependence, indicate that mechanisms may exist other than ionization of bare U atoms after the stepwise photodissociation of F atoms from the parent molecule.

Armstrong, D.P. (Oak Ridge K-25 Site, TN (United States). UEO Enrichment Technical Operations Div.) [Oak Ridge K-25 Site, TN (United States). UEO Enrichment Technical Operations Div.

1992-05-01T23:59:59.000Z

147

Modulated voltage metastable ionization detector  

SciTech Connect

Metastable ionization detectors used for chromatographic analysis usually employa fixed high voltage for the ionization potential. For this reason, the operating range is limited to about three orders of magnitude. By use of the technique disclosed in the instant invention, operating ranges of about nine orders of magnitude are obtained. The output current from a metastable ionization detector (MID) is applied to a modulation voltage circuit. An adjustment is made to balance out the background current, and an output current, above background, is applied to an input of a strip chart recorder. For low level concentrations, i.e., low detected output current, the ionization potential will be at a maximum and the metastable ionization detector will operate at its most sensitive level. When the detected current from the metastable ionization detector increases above a predetermined threshold level, a voltage control circuit is activated which turns on a high voltage transistor which acts to reduce the ionization potential. The ionization potential applied to the metastable ionization detector is then varied so as to maintain the detected signal level constant. The variation in ionization potential is now related to the concentration fo the constituent and a representative amplitude is applied to another input of said strip chart recorder.

Carle, G. C.; Humphry, D. E.; Kojiro, D. R.

1985-08-27T23:59:59.000Z

148

A surface ionization source  

E-Print Network (OSTI)

The Einzel Lens. 2 The Quadrupole Triplet . . 3. The Beam Scanner. . . 4 The Four-plate Detectors and Faraday Cups. III TESTING AND OPTIMIZING THE BEAM LINE 10 12 13 A. Initial Results. IV THE THEORY OF SURFACE IONIZATION . . . . . V ION SOURCES. 21... aperture and through a beam scanner. The scanner translates the beam's cross-section to an image visible on the oscilloscope A movable Faraday cup connected to a sensitive electrometer is used to maximize the beam transmission at the opening into the 2...

Buzatu, Daniel J.

2012-06-07T23:59:59.000Z

149

Plasma Production via Field Ionization  

SciTech Connect

Plasma production via field ionization occurs when an incoming particle beam is sufficiently dense that the electric field associated with the beam ionizes a neutral vapor or gas. Experiments conducted at the Stanford Linear Accelerator Center explore the threshold conditions necessary to induce field ionization by an electron beam in a neutral lithium vapor. By independently varying the transverse beam size, number of electrons per bunch or bunch length, the radial component of the electric field is controlled to be above or below the threshold for field ionization. Additional experiments ionized neutral xenon and neutral nitric oxide by varying the incoming beam's bunch length. A self-ionized plasma is an essential step for the viability of plasma-based accelerators for future high-energy experiments.

O'Connell, C.L.; Barnes, C.D.; Decker, F.; Hogan, M.J.; Iverson, R.; Krejcik, P.; Siemann, R.; Walz, D.R.; /SLAC; Clayton, C.E.; Huang, C.; Johnson, D.K.; Joshi, C.; Lu,; Marsh, K.A.; Mori, W.; Zhou, M.; /UCLA; Deng, S.; Katsouleas, T.; Muggli, P.; Oz, E.; /Southern California U.

2007-01-02T23:59:59.000Z

150

A numerical scheme for ionizing shock waves  

SciTech Connect

A two-dimensional (2D) visual computer code to solve the steady state (SS) or transient shock problems including partially ionizing plasma is presented. Since the flows considered are hypersonic and the resulting temperatures are high, the plasma is partially ionized. Hence the plasma constituents are electrons, ions and neutral atoms. It is assumed that all the above species are in thermal equilibrium, namely, that they all have the same temperature. The ionization degree is calculated from Saha equation as a function of electron density and pressure by means of a nonlinear Newton type root finding algorithms. The code utilizes a wave model and numerical fluctuation distribution (FD) scheme that runs on structured or unstructured triangular meshes. This scheme is based on evaluating the mesh averaged fluctuations arising from a number of waves and distributing them to the nodes of these meshes in an upwind manner. The physical properties (directions, strengths, etc.) of these wave patterns are obtained by a new wave model: ION-A developed from the eigen-system of the flux Jacobian matrices. Since the equation of state (EOS) which is used to close up the conservation laws includes electronic effects, it is a nonlinear function and it must be inverted by iterations to determine the ionization degree as a function of density and temperature. For the time advancement, the scheme utilizes a multi-stage Runge-Kutta (RK) algorithm with time steps carefully evaluated from the maximum possible propagation speed in the solution domain. The code runs interactively with the user and allows to create different meshes to use different initial and boundary conditions and to see changes of desired physical quantities in the form of color and vector graphics. The details of the visual properties of the code has been published before (see [N. Aslan, A visual fluctuation splitting scheme for magneto-hydrodynamics with a new sonic fix and Euler limit, J. Comput. Phys. 197 (2004) 1-27]). The two-dimensional nature of ION-A was presented by a planar shock wave propagating over a circular obstacle. It was demonstrated that including the effects of ionization in calculating complex flows is important, even when they appear initially negligible. This code can be used to accurately simulate the nonlinear time dependent evolution of neutral or ionized plasma flows from supersonic to hypersonic regimes.

Aslan, Necdet [Yeditepe University, Physics Department, Kayisda g-circumflex i, 34755 Istanbul (Turkey)]. E-mail: naslan@yeditepe.edu.tr; Mond, Michael [Ben Gurion University, Mechanical Engineering Department, Beer Sheva (Israel)

2005-12-10T23:59:59.000Z

151

C3Bio.org - Tags: Mass Spectrometry Data  

NLE Websites -- All DOE Office Websites (Extended Search)

Dave J Borton, Hilkka Inkeri Kenttamaa Developments in atmospheric pressure ionization (API) techniques have revolutionized the mass spectrometric analysis of large and...

152

Thermally actuated thermionic switch  

DOE Patents (OSTI)

A thermally actuated thermionic switch which responds to an increase of temperature by changing from a high impedance to a low impedance at a predictable temperature set point. The switch has a bistable operation mode switching only on temperature increases. The thermionic material may be a metal which is liquid at the desired operation temperature and held in matrix in a graphite block reservoir, and which changes state (ionizes, for example) so as to be electrically conductive at a desired temperature.

Barrus, D.M.; Shires, C.D.

1982-09-30T23:59:59.000Z

153

Ionizing radiation detector  

DOE Patents (OSTI)

An ionizing radiation detector is provided which is based on the principle of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

Thacker, Louis H. (Knoxville, TN)

1990-01-01T23:59:59.000Z

154

An Electrospray Ionization Source for Integration with Microfluidics  

Science Journals Connector (OSTI)

An Electrospray Ionization Source for Integration with Microfluidics ... Mass spectrometry plays a key role in such analysis, and there are many advantages in efficiency and sample consumption that can be attained by the use of microfluidics. ... Digital Microfluidics with In-Line Sample Purification for Proteomics Analyses with MALDI-MS ...

Jun Kameoka; Reid Orth; Bojan Ilic; David Czaplewski; Tim Wachs; H. G. Craighead

2002-10-22T23:59:59.000Z

155

Proteasome Structures Affected by Ionizing Radiation  

Science Journals Connector (OSTI)

...Effect of ionizing radiation on 26S but...radiation doses, and immediately...the dose range 1 to 20 Gy...ionizing radiation induced a...38), ionizing radiation (39...over a wide range of radiation doses and further...

Milena Pervan; Keisuke S. Iwamoto; and William H. McBride

2005-07-01T23:59:59.000Z

156

Double-gated isolated vertically aligned carbon nanofiber field emission and field ionization arrays  

E-Print Network (OSTI)

Electron impact ionization (ElI) is used extensively in mass spectrometry for gas-phase analytes. Due to the significant amount of fragmentation generated by ElI, the spectrum is usually very noisy. In addition, the ...

Chen, Liang-Yu, 1979-

2007-01-01T23:59:59.000Z

157

Optical ionization detector  

DOE Patents (OSTI)

An optical ionization detector wherein a beam of light is split so that one arm passes through a fiber optics and the other arm passes through a gas-filled region, and uses interferometry to detect density changes in a gas when charged particles pass through it. The gas-filled region of the detector is subjected to a high electric field and as a charged particle traverses this gas region electrons are freed from the cathode and accelerated so as to generate an electron avalanche which is collected on the anode. The gas density is effected by the electron avalanche formation and if the index or refraction is proportional to the gas density the index will change accordingly. The detector uses this index change by modulating the one arm of the split light beam passing through the gas, with respect to the other arm that is passed through the fiber optic. Upon recombining of the beams, interference fringe changes as a function of the index change indicates the passage of charged particles through the gaseous medium. 3 figures.

Wuest, C.R.; Lowry, M.E.

1994-03-29T23:59:59.000Z

158

Optical ionization detector  

DOE Patents (OSTI)

An optical ionization detector wherein a beam of light is split so that one arm passes through a fiber optics and the other arm passes through a gas-filled region, and uses interferometry to detect density changes in a gas when charged particles pass through it. The gas-filled region of the detector is subjected to a high electric field and as a charged particle traverses this gas region electrons are freed from the cathode and accelerated so as to generate an electron avalanche which is collected on the anode. The gas density is effected by the electron avalanche formation and if the index or refraction is proportional to the gas density the index will change accordingly. The detector uses this index change by modulating the one arm of the split light beam passing through the gas, with respect to the other arm that is passed through the fiber optic. Upon recombining of the beams, interference fringe changes as a function of the index change indicates the passage of charged particles through the gaseous medium.

Wuest, Craig R. (Danville, CA); Lowry, Mark E. (Castro Valley, CA)

1994-01-01T23:59:59.000Z

159

Resonance Ionization Laser Ion Sources  

E-Print Network (OSTI)

The application of the technique of laser resonance ionization to the production of singly charged ions at radioactive ion beam facilities is discussed. The ability to combine high efficiency and element selectivity makes a resonance ionization laser ion source (RILIS) an important component of many radioactive ion beam facilities. At CERN, for example, the RILIS is the most commonly used ion source of the ISOLDE facility, with a yearly operating time of up to 3000 hours. For some isotopes the RILIS can also be used as a fast and sensitive laser spectroscopy tool, provided that the spectral resolution is sufficiently high to reveal the influence of nuclear structure on the atomic spectra. This enables the study of nuclear properties of isotopes with production rates even lower than one ion per second and, in some cases, enables isomer selective ionization. The solutions available for the implementation of resonance laser ionization at radioactive ion beam facilities are summarized. Aspects such as the laser r...

Marsh, B

2013-01-01T23:59:59.000Z

160

Field ionization from carbon nanofibers  

E-Print Network (OSTI)

The Micro Gas Analyzer project aims to develop power-efficient, high resolution, high sensitivity, portable and real-time gas sensors. We developed a field ionizer array based on gated CNTs. Arrays of CNTs are used because ...

Adeoti, Bosun J

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Ionizing Radiation Injury (South Carolina)  

Energy.gov (U.S. Department of Energy (DOE))

This legislation applies to employers that have more than one employee who engages in activities which involve the presence of ionizing radiation. Employers with less than three employees can...

162

Mass spectrometry: analytical capabilities and potentials  

Science Journals Connector (OSTI)

...INSULIN AND OTHER LARGE PEPTIDES, JOURNAL...MASS-SPECTROMETRY OF LARGE, FRAGILE, AND INVOLATILE...APPLICATIONS IN THE AREA OF MOLECULAR MODIFICATIONS...I-127-LABELED PLASMA DESORPTION MASS-SPECTROMETRY...PIONEER VENUS LARGE PROBE NEUTRAL MASS-SPECTROMETER...HORNING, E.C., ATMOSPHERIC-PRESSURE IONIZATION...

RG Cooks; KL Busch; GL Glish

1983-10-21T23:59:59.000Z

163

Thermal and non-thermal energies in solar flares  

E-Print Network (OSTI)

The energy of the thermal flare plasma and the kinetic energy of the non-thermal electrons in 14 hard X-ray peaks from 9 medium-sized solar flares have been determined from RHESSI observations. The emissions have been carefully separated in the spectrum. The turnover or cutoff in the low-energy distribution of electrons has been studied by simulation and fitting, yielding a reliable lower limit to the non-thermal energy. It remains the largest contribution to the error budget. Other effects, such as albedo, non-uniform target ionization, hot target, and cross-sections on the spectrum have been studied. The errors of the thermal energy are about equally as large. They are due to the estimate of the flare volume, the assumption of the filling factor, and energy losses. Within a flare, the non-thermal/thermal ratio increases with accumulation time, as expected from loss of thermal energy due to radiative cooling or heat conduction. Our analysis suggests that the thermal and non-thermal energies are of the same magnitude. This surprising result may be interpreted by an efficient conversion of non-thermal energy to hot flare plasma.

Pascal Saint-Hilaire; Arnold O. Benz

2005-03-03T23:59:59.000Z

164

Radial arrays of nano-electrospray ionization emitters and methods of forming electrosprays  

DOE Patents (OSTI)

Electrospray ionization emitter arrays, as well as methods for forming electrosprays, are described. The arrays are characterized by a radial configuration of three or more nano-electrospray ionization emitters without an extractor electrode. The methods are characterized by distributing fluid flow of the liquid sample among three or more nano-electrospray ionization emitters, forming an electrospray at outlets of the emitters without utilizing an extractor electrode, and directing the electrosprays into an entrance to a mass spectrometry device. Each of the nano-electrospray ionization emitters can have a discrete channel for fluid flow. The nano-electrospray ionization emitters are circularly arranged such that each is shielded substantially equally from an electrospray-inducing electric field.

Kelly, Ryan T [West Richland, WA; Tang, Keqi [Richland, WA; Smith, Richard D [Richland, WA

2010-10-19T23:59:59.000Z

165

Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Analysis of Large Polymerases Chain Reaction Products  

SciTech Connect

We have attempted to expand the size range of PCR products that can be analyzed by electroscopy ionization (ESI) Fourier transformion cyclotron resonance (FTICR) mass spectrometry. The mass measurement accuracy obtained illustrates that a signel base substitution could be identified at the size of PCR product with a 7 tesla ESI-FTICR

Wunschel, David S.(BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB); Pasa Tolic, Ljiljana (BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB); Feng, Bingbing (ASSOC WESTERN UNIVERSITY) [ASSOC WESTERN UNIVERSITY; Smith, Richard D.(BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB)

2000-04-01T23:59:59.000Z

166

Thermal and non-thermal energies in solar flares  

E-Print Network (OSTI)

The energy of the thermal flare plasma and the kinetic energy of the non-thermal electrons in 14 hard X-ray peaks from 9 medium-sized solar flares have been determined from RHESSI observations. The emissions have been carefully separated in the spectrum. The turnover or cutoff in the low-energy distribution of electrons has been studied by simulation and fitting, yielding a reliable lower limit to the non-thermal energy. It remains the largest contribution to the error budget. Other effects, such as albedo, non-uniform target ionization, hot target, and cross-sections on the spectrum have been studied. The errors of the thermal energy are about equally as large. They are due to the estimate of the flare volume, the assumption of the filling factor, and energy losses. Within a flare, the non-thermal/thermal ratio increases with accumulation time, as expected from loss of thermal energy due to radiative cooling or heat conduction. Our analysis suggests that the thermal and non-thermal energies are of the same m...

Saint-Hilaire, P; Saint-Hilaire, Pascal; Benz, Arnold O.

2005-01-01T23:59:59.000Z

167

Electron impact ionization of neutral and ionized fullerenes: ionization cross–sections and kinetic energy release  

Science Journals Connector (OSTI)

...and 1000 eV, with an energy spread of approximately...exit electrode by an electric field penetrating from...measurements of appearance energies and ionization cross-sections...measurements have been car- ried out (in both...cross-sections versus electron energy from threshold up to...

1999-01-01T23:59:59.000Z

168

Ambient Sampling/Ionization Mass Spectrometry: Applications and Current Trends  

Science Journals Connector (OSTI)

drugs of abuse ... We felt that because ambient techniques are still young, fundamental studies are still critically needed to understand the range of applications that can be enabled by their use. ... The detection of counterfeit drugs is of particular interest since it is a growing issue in developing countries and over the Internet. ...

Glenn A. Harris; Asiri S. Galhena; Facundo M. Fernández

2011-04-15T23:59:59.000Z

169

Design optimization of thermal paths in spacecraft systems  

E-Print Network (OSTI)

This thesis introduces a thermal design approach to increase thermal control system performance and decrease reliance on system resources, e.g., mass. Thermal design optimization has lagged other subsystems because the ...

Stout, Kevin Dale

2013-01-01T23:59:59.000Z

170

Lesson 4 - Ionizing Radiation | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

4 - Ionizing Radiation 4 - Ionizing Radiation Lesson 4 - Ionizing Radiation Lesson Three showed that unstable isotopes emit energy as they become more stable. This energy is known as radiation. This lesson explores forms of radiation, where radiation is found, how we detect and measure radiation, what sources of radiation people are exposed to, whether radiation is harmful, and how we can limit our exposure. Specific topics covered in this lesson include: Types of radiation Non-ionizing Ionizing Forms of ionizing radiation Alpha particles Beta particles Gamma rays Radiation Decay chain Half-life Dose Radiation measurements Sources of radiation Average annual exposure Lesson 4 - Ionizing Radiation.pptx More Documents & Publications DOE-HDBK-1130-2008 DOE-HDBK-1130-2008 DOE-HDBK-1130-2007

171

Measurement of spin-exchange effects in electron-hydrogen collisions: Further studies of impact ionization  

SciTech Connect

Using a Fano-effect polarized electron source and a state-selected thermally dissociated hydrogen beam, we measured the interference between the direct and exchange scattering amplitudes for electron-impact ionization of atomic hydrogen between 13.8 and 30.0 eV. We report the data from these measurements and the results of corrections applied to previously published data.

Gay, T.J.; Fletcher, G.D.; Alguard, M.J.; Hughes, V.W.; Wainwright, P.F.; Lubell, M.S.

1982-12-01T23:59:59.000Z

172

The multiphoton ionization of uranium hexafluoride. Revision 1  

SciTech Connect

Multiphoton ionization (MPI) time-of-flight mass spectroscopy and photoelectron spectroscopy studies of UF{sub 6} have been conducted using focused light from the Nd:YAG laser fundamental ({lambda}=1064 nm) and its harmonics ({lambda}=532, 355, or 266 nm), as well as other wavelengths provided by a tunable dye laser. The MPI mass spectra are dominated by the singly and multiply charged uranium ions rather than by the UF{sub x}{sup +} fragment ions even at the lowest laser power densities at which signal could be detected. The laser power dependence of U{sup n+} ions signals indicates that saturation can occur for many of the steps required for their ionization. In general, the doubly-charged uranium ion (U{sup 2+}) intensity is much greater than that of the singly-charged uranium ion (U{sup +}). For the case of the tunable dye laser experiments, the U{sup n+} (n = 1- 4) wavelength dependence is relatively unstructured and does not show observable resonance enhancement at known atomic uranium excitation wavelengths. The dominance of the U{sup 2+} ion and the absence or very small intensities of UF{sub x}{sup +} fragments, along with the unsaturated wavelength dependence, indicate that mechanisms may exist other than ionization of bare U atoms after the stepwise photodissociation of F atoms from the parent molecule.

Armstrong, D.P. [Oak Ridge K-25 Site, TN (United States). UEO Enrichment Technical Operations Div.] [Oak Ridge K-25 Site, TN (United States). UEO Enrichment Technical Operations Div.

1992-05-01T23:59:59.000Z

173

Ionizing radiation effects on silicon test structures  

SciTech Connect

The effects of {sup 60}Co gamma irradiation on MOSCAPS and special junction diode detectors have been studied. The capacitors were used to ellicit the charge accumulation and anneal in two types of thermally grown oxides representative of those used in routine detector processing. Ion implanted, oxide passivated junction detectors having 0.25 and 1 cm{sup 2} areas and perimeter to area ratios of 1 (a square), 2 and 5 were designed and constructed to amplify the ionizing effects expected to largely affect junction edges through changes in fixed oxide charges. Detectors were exposed to over 4 Mrad and showed clear increases in leakage current in proportion to the junction edge length. Annealing schedules were determined to provide a continuous response to incremental irradiations and subsequent room temperature anneals of leakage current. Besides an increase in gate threshold, little effect on the C(V) response was found. PISCES simulation of the edge fields using different fixed oxide charge revealed regions of very high lateral fields near the junction edges for fixed charges in the 2 {times} 10{sup 12}/cm{sup 2} range expected from the capacitor studies which could be responsible for the observed leakage currents.

Kraner, H.W.; Beuttenmuller, R.; Chen, W.; Kierstead, J.A.; Li, Z.; Zhang, Y. [Brookhaven National Lab., Upton, NY (United States); Dou, L. [Wayne State Univ., Detroit, MI (United States); Fretwurst, E.; Lindstroem, G. [Univ. of Hamburg (Germany)

1993-12-01T23:59:59.000Z

174

In situ transmission electron microscopy observation of silver oxidation in ionized/atomic gas.  

SciTech Connect

The interaction between silver and ionized and atomic gas was observed directly by in situ transmission electron microscopy with an environmental cell for the first time. The electron beam provides dual functions as the source of both gas ionization and imaging. The concentration of ionized gas was tuned via adjusting the current density of the electron beam. Oxidation of the silver is observed in situ, indicating the presence of ionized and/or atomic oxygen. The evolution of microstructure and phase constituents was characterized. Then the oxidation rate was measured, and the relationships among grain size, mass transport rate, and electron flux were characterized. The role of the electron beam is discussed, and the results are rationalized with respect to ex situ results from the literature.

Sun, L.; Noh, K. W.; Wen, J-G.; Dillon, S. J. (Materials Science Division); (Massachusetts Inst. Tech.); (Univ. Illinois - Urbana)

2011-10-17T23:59:59.000Z

175

Design and Analyisi of a Self-centered Cold Mass Support for the MICE Coupling Magnet  

SciTech Connect

The Muon Ionization Cooling Experiment (MICE) consists of eighteen superconducting solenoid coils in seven modules, which are magnetically hooked together since there is no iron to shield the coils and the return flux. The RF coupling coil (RFCC) module consists of a superconducting coupling solenoid mounted around four conventional conducting 201.25 MHz closed RF cavities. The coupling coil will produce up to a 2.2 T magnetic field on the centerline to keep the beam within the RF cavities. The peak magnetic force on the coupling magnet from other magnets in MICE is up to 500 kN in longitudinal direction, which will be transferred to the base of the RF coupling coil (RFCC) module through a cold mass support system. A self-centered double-band cold mass support system with intermediate thermal interruption is applied to the coupling magnet, and the design is introduced in detail in this paper. The thermal and structural analysis on the cold mass support assembly has been carried out using ANSYS. The present design of the cold mass support can satisfy with the stringent requirements for the magnet center and axis azimuthal angle at 4.2 K and fully charged.

Wang, Li; Pan, Heng; Wu, Hong; Li, S. Y.; Guo, Xing Long; Zheng, Shi Xian; Green, Michael A.

2011-05-04T23:59:59.000Z

176

Detailed Analysis of Thermal Mass Effects in a Code-Traceable DOE-2 Simulation of the 2000 IECC for a Single-Family Residence in Texas: A Project for Texas' Senate Bill 5 Legislation for Reducing Pollution in Nonattainment and Affected Areas  

E-Print Network (OSTI)

This study examines the thermal mass effects in a code-traceable DOE-2 simulation of the 2000 IECC (International Energy Conservation Code) for a single-family residence in Texas. This report is composed of two major simulations: 1) the simulation...

Kim, S.; Haberl, J. S.

2008-07-18T23:59:59.000Z

177

WARM IONIZED GAS REVEALED IN THE MAGELLANIC BRIDGE TIDAL REMNANT: CONSTRAINING THE BARYON CONTENT AND THE ESCAPING IONIZING PHOTONS AROUND DWARF GALAXIES  

SciTech Connect

The Magellanic System includes some of the nearest examples of galaxies disturbed by galaxy interactions. These interactions have redistributed much of their gas into the halos of the Milky Way (MW) and the Magellanic Clouds. We present Wisconsin H{alpha} Mapper kinematically resolved observations of the warm ionized gas in the Magellanic Bridge over the velocity range of +100 to +300 km s{sup -1} in the local standard of rest reference frame. These observations include the first full H{alpha} intensity map and the corresponding intensity-weighted mean velocity map of the Magellanic Bridge across (l, b) = (281 Degree-Sign .5, -30 Degree-Sign .0) to (302. Degree-Sign 5, -46. Degree-Sign 7). Using the H{alpha} emission from the Small Magellanic Cloud (SMC)-Tail and the Bridge, we estimate that the mass of the ionized material is between (0.7-1.7) Multiplication-Sign 10{sup 8} M{sub Sun }, compared to 3.3 Multiplication-Sign 10{sup 8} M{sub Sun} for the neutral mass over the same region. The diffuse Bridge is significantly more ionized than the SMC-Tail, with an ionization fraction of 36%-52% compared to 5%-24% for the Tail. The H{alpha} emission has a complex multiple-component structure with a velocity distribution that could trace the sources of ionization or distinct ionized structures. We find that incident radiation from the extragalactic background and the MW alone are insufficient to produced the observed ionization in the Magellanic Bridge and present a model for the escape fraction of the ionizing photons from both the SMC and Large Magellanic Cloud (LMC). With this model, we place an upper limit of 4.0% for the average escape fraction of ionizing photons from the LMC and an upper limit of 5.5% for the SMC. These results, combined with the findings of a half a dozen other studies for dwarf galaxies in different environments, provide compelling evidence that only a small percentage of the ionizing photons escape from dwarf galaxies in the present epoch to influence their surroundings.

Barger, K. A.; Haffner, L. M. [Department of Astronomy, University of Wisconsin-Madison, Madison, WI 53706 (United States); Bland-Hawthorn, J., E-mail: kbargers@nd.edu, E-mail: haffner@astro.wisc.edu, E-mail: jbh@physics.usyd.edu.au [Sydney Institute for Astronomy, School of Physics A28, University of Sydney, NSW 2006 (Australia)

2013-07-10T23:59:59.000Z

178

The Cryogenic Dark Matter Search: First 5-Tower Data and Improved Understanding of Ionization Collection  

SciTech Connect

The Cryogenic Dark Matter Search (CDMS) is searching for Weakly Interacting Massive Particles (WIMPs) with cryogenic particle detectors. These detectors have the ability to discriminate between nuclear recoil candidate and electron recoil background events by collecting both phonon and ionization energy from recoils in the detector crystals. The CDMS-II experiment has completed analysis of the first data runs with 30 semiconductor detectors at the Soudan Underground Laboratory, resulting in a world leading WIMP-nucleon spin-independent cross section limit for WIMP masses above 44 GeV/c{sup 2}. As CDMS aims to achieve greater WIMP sensitivity, it is necessary to increase the detector mass and discrimination between signal and background events. Incomplete ionization collection results in the largest background in the CDMS detectors as this causes electron recoil background interactions to appear as false candidate events. Two primary causes of incomplete ionization collection are surface and bulk trapping. Recent work has been focused on reducing surface trapping through the modification of fabrication methods for future detectors. Analyzing data taken with test devices has shown that hydrogen passivation of the amorphous silicon blocking layer worsens surface trapping. Additional data has shown that the iron-ion implantation used to lower the critical temperature of the tungsten transition-edge sensors causes a degradation of the ionization collection. Using selective implantation on future detectors may improve ionization collection for events near the phonon side detector surface. Bulk trapping is minimized by neutralizing ionized lattice impurities. Detector investigations at testing facilities and in situ at the experimental site have provided methods to optimize the neutralization process and monitor running conditions to maintain full ionization collection. This work details my contribution to the 5-tower data taking, monitoring, and analysis effort as well as the SuperCDMS detector development with the focus on monitoring and improving ionization collection in the detectors.

Bailey, Catherine N.; /Case Western Reserve U.

2010-01-01T23:59:59.000Z

179

Ionization probes of molecular structure and chemistry  

SciTech Connect

Various photoionization processes provide very sensitive probes for the detection and understanding of the spectra of molecules relevant to combustion processes. The detection of ionization can be selective by using resonant multiphoton ionization or by exploiting the fact that different molecules have different sets of ionization potentials. Therefore, the structure and dynamics of individual molecules can be studied even in a mixed sample. The authors are continuing to develop methods for the selective spectroscopic detection of molecules by ionization, and to use these methods for the study of some molecules of combustion interest.

Johnson, P.M. [State Univ. of New York, Stony Brook (United States)

1993-12-01T23:59:59.000Z

180

Chemical oxidation of tryptic digests to improve sequence coverage in peptide mass fingerprint protein identification  

E-Print Network (OSTI)

Peptide mass fingerprinting (PMF) of protein digests is a widely-accepted method for protein identification in MS-based proteomic studies. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI) is the technique of choice in PMF...

Lucas, Jessica Elaine

2004-09-30T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Department of Chemistry Mass Spectrometry Sample Submission Form  

E-Print Network (OSTI)

's ID. · You are responsible to pick up your samples within 7 days after the analysis. · Please call 801: [ ] Standard (LRMS) [ ] Exact Mass (HRMS) Ionization type: [ ] ESI [ ] MALDI [ ] EI (GC/MS only) Scans required

Simons, Jack

182

Metabolic Differences in Microbial Cell Populations Revealed by Nanophotonic Ionization  

SciTech Connect

ellular differences are linked to cell differentiation, the proliferation of cancer and to the development of drug resistance in microbial infections. Due to sensitivity limitations, however, large- scale metabolic analysis at the single cell level is only available for cells significantly larger in volume than Saccharomyces cerevisiae (~30 fL). Here we demonstrate that by a nanophotonic ionization platform and mass spectrometry, over one hundred up to 108 metabolites, or up to 18% of the known S. cerevisiae metabolome, can be identified in very small cell populations (n < 100). Under ideal conditions, r Relative quantitation of up to 4% of the metabolites is achieved at the single cell level.

Walker, Bennett [George Washington University] [George Washington University; Antonakos, Cory [George Washington University] [George Washington University; Retterer, Scott T [ORNL] [ORNL; Vertes, Akos [George Washington University] [George Washington University

2013-01-01T23:59:59.000Z

183

Device for detecting ionizing radiation  

SciTech Connect

The present invention relates to ionizing radiation sensors, and , more particularly, to semiconductor spectrometers with thermoelectric cooling, and can most advantageously be used in mineral raw material exploration and evaluation under field conditions. The spectrometer comprises a vacuum chamber with an entrance window for passing the radiation therethrough. The vacuum chamber accommodates a thermoelectric cooler formed by a set of peltier elements. A heat conducting plate is mounted on the cold side of the thermoelectric cooler, and its hot side is provided with a radiator. Mounted on the heat conducting plate are sets of peltier elements, integral with the thermoelectric cooler and independent of one another. The peltier elements of these sets are stacked so as to develop the minimum temperature conditions on one set carrying a semiconductor detector and to provide the maximum refrigeration capacity conditions on the other set provided with the field-effect transistor mounted thereon.

Anatychuk, L.I.; Kharitonov, J.P.; Kusniruk, V.F.; Meir, V.A.; Melnik, A.P.; Ponomarev, V.S.; Skakodub, V.A.; Sokolov, A.D.; Subbotin, V.G.; Zhukovsky, A.N.

1980-10-28T23:59:59.000Z

184

Ionization tube simmer current circuit  

DOE Patents (OSTI)

A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current.

Steinkraus, Jr., Robert F. (Livermore, CA)

1994-01-01T23:59:59.000Z

185

Ionization tube simmer current circuit  

DOE Patents (OSTI)

A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current. 6 figures.

Steinkraus, R.F. Jr.

1994-12-13T23:59:59.000Z

186

E-Print Network 3.0 - absorptions exploiting photo-thermal Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

photo-thermal ionization of neutral donors (D0 D+ + e- ) with no signicant electron heat- ing... , Bu alo, NY 14260, USA Abstract Resonant magneto-absorption of far-infrared...

187

Ionization equilibrium and equation of state of hydrogen plasmas in strong magnetic fields  

E-Print Network (OSTI)

We study hydrogen plasmas at magnetic fields B ~ 10^{12}-10^{13} Gauss, densities ~ 10^{-3}-10^3 g/cc and temperatures T ~ 10^{5.5}-10^{6.5} K, typical of photospheres of middle-aged cooling neutron stars. We construct an analytical free energy model of the partially ionized plasma, including into consideration the decentred atomic states, which arise due to the thermal motion across the strong field. We show that these states, neglected in previous studies, may contribute appreciably into thermodynamics of the outer atmospheric layers at density below 1 g/cc and typical B and T. We take into account Coulomb non-ideality of the ionized component of the plasma affected by intense magnetic field. Ionization degree, occupancies and equation of state are calculated, and their dependences on the temperature, density and magnetic field are studied.

Potekhin, A Yu; Shibanov, Yu A; Ventura, J; Shibanov, Yu. A.

1999-01-01T23:59:59.000Z

188

Ionization equilibrium and equation of state of hydrogen plasmas in strong magnetic fields  

E-Print Network (OSTI)

We study hydrogen plasmas at magnetic fields B ~ 10^{12}-10^{13} Gauss, densities ~ 10^{-3}-10^3 g/cc and temperatures T ~ 10^{5.5}-10^{6.5} K, typical of photospheres of middle-aged cooling neutron stars. We construct an analytical free energy model of the partially ionized plasma, including into consideration the decentred atomic states, which arise due to the thermal motion across the strong field. We show that these states, neglected in previous studies, may contribute appreciably into thermodynamics of the outer atmospheric layers at density below 1 g/cc and typical B and T. We take into account Coulomb non-ideality of the ionized component of the plasma affected by intense magnetic field. Ionization degree, occupancies and equation of state are calculated, and their dependences on the temperature, density and magnetic field are studied.

A. Y. Potekhin; G. Chabrier; Yu. A. Shibanov; J. Ventura

1998-11-27T23:59:59.000Z

189

Neutron And Gamma Detector Using An Ionization Chamber With An...  

NLE Websites -- All DOE Office Websites (Extended Search)

Neutron And Gamma Detector Using An Ionization Chamber Neutron And Gamma Detector Using An Ionization Chamber With An Integrated Body And Moderator A detector for detecting...

190

Photo double ionization of ethylene and acetylene near threshold  

E-Print Network (OSTI)

Photo double ionization of ethylene and acetylene nearcomplete measurements of the photo double ionization ofkinetic energy of the photo electrons and the nuclear

Gaire, B.

2014-01-01T23:59:59.000Z

191

Direct Experimental Observation of the Low Ionization Potentials...  

NLE Websites -- All DOE Office Websites (Extended Search)

Observation of the Low Ionization Potentials of Guanine in Free Oligonucleotides by Using Photoelectron Direct Experimental Observation of the Low Ionization Potentials of Guanine...

192

Photo double ionization of ethylene and acetylene near threshold  

E-Print Network (OSTI)

double ionization of ethylene and acetylene near thresholdphoto double ionization of ethylene (dou- ble CC bond) andsimilar yields of metastable ethylene dications produced by

Gaire, B.

2014-01-01T23:59:59.000Z

193

Apparatus for preparing a sample for mass spectrometry  

DOE Patents (OSTI)

An apparatus is described for preparing a sample for analysis by a mass spectrometer system. The apparatus has an entry chamber and an ionization chamber separated by a skimmer. A capacitor having two space-apart electrodes followed by one or more ion-imaging lenses is disposed in the ionization chamber. The chamber is evacuated and the capacitor is charged. A valve injects a sample gas in the form of sample pulses into the entry chamber. The pulse is collimated by the skimmer and enters the ionization chamber. When the sample pulse passes through the gap between the electrodes, it discharges the capacitor and is thereby ionized. The ions are focused by the imaging lenses and enter the mass analyzer, where their mass and charge are analyzed. 1 figures.

Villa-Aleman, E.

1994-05-10T23:59:59.000Z

194

Anomalous laser-induced ionization rates of molecules and rare-gas atoms  

SciTech Connect

Electron tunnel ionization is considered as the mechanism for producing free electrons in gases under laser radiation. The Keldysh result and the Ammosov-Delone-Krainov (ADK) formulation are amended by considering the excess forces due to the interaction of the electric field of the laser with the electron cloud in a simple mass-on-a-spring approximation. The result of this excess force is a kinetic energy that is directed along the polarization vector of the laser field and an induced potential energy that are proposed as a determining factor in electron tunnel ionization. Relative ionization rates for various pairs of gases are calculated and compared with reported figures. Comparisons were made between several combinations of O{sub 2}, Xe, Ar, N{sub 2}, Cl{sub 2}, H{sub 2}, CO, Kr, NO, F{sub 2}, and D{sub 2}. Predicted ratios of ionization rates between pairs of gases are compared to ADK predictions. Apparently anomalous ionization rates of O{sub 2}, D{sub 2}, and H{sub 2} are explained. A simple expression is developed that reveals why the ionization rate of Xe is about an order of magnitude larger than that of O{sub 2} even though their ionization potentials are nearly identical; why CO is only about half that of Kr even though their ionization potentials are nearly the same; why the ratio of O{sub 2} to O is about ten times larger than predicted by ADK; and why the ratio of NO to Xe is about an order of magnitude less than predicted by ADK.

Bettis, Jerry Ray [5701 Woodlake Drive, Stillwater, Oklahoma 74074 (United States)

2009-12-15T23:59:59.000Z

195

Photo-Electric Ionization of Caesium Vapor  

Science Journals Connector (OSTI)

Measurement of photo-electric ionization in gases.—The current from a filament, normally limited by space change, is increased by the presence of positive ions. As shown by Kingdon this effect may be greatly magnified if a small cathode is practically enclosed by the anode so that the ions are imprisoned. This method was used for the detection of photo-electric ionization. Besides possessing extreme sensitivity it is unaffected by photo-electric emission from the electrodes.Photo-electric effect in caesium vapor.—The change in thermionic current with the unresolved radiation from a mercury arc was measured as functions of the applied voltage, filament temperature, and vapor pressure. Then the photo-electric effect as a function of wave-length was studied using a monochromatic illuminator to disperse light from the arc or a Mazda lamp. The ionization per unit flux was found to increase with increasing wave-length to a sharp maximum at the limit 1s=3184A of the principal series, as is required by the Bohr theory. For longer wave-lengths the ionization decreased to about 10 percent at 3400A. Photo-excitation. The simple theory does not admit of ionization by wave-lengths greater than 3184A but the data are in qualitative agreement with the hypothesis that such radiation produces excited atoms which upon collision with other atoms acquire sufficient additional energy to become ionized. Hence, unlike an x-ray limit, the photo-ionization effect for a valence electron is not sharply discontinuous at the true threshold for direct ionization.Photo-ionization photometer and intensitometer. A tube of the type described, with suitable gases for the range of wave-length involved, may be used as a photometer or may be calibrated to measure intensity of radiation directly.

Paul D. Foote and F. L. Mohler

1925-08-01T23:59:59.000Z

196

Ionization threshold of crystalline LiF  

Science Journals Connector (OSTI)

The ionization threshold for crystalline LiF is calculated using a cluster embedded model. The experimental ionization threshold is 9.8 eV; however, previous band and cluster model calculations gave 14–15 eV. These earlier calculations used a crystal having a perfect lattice. In the present work, a crystal with lattice defects is introduced. The calculated surface and bulk ionization thresholds are 8.1 and 8.7 eV, respectively, showing good correspondence with experiment. The electron affinity and other band parameters are also studied.

Hiroshi Tatewaki

1999-08-01T23:59:59.000Z

197

Nonlinearities in Flame Ionization Detector Response  

Science Journals Connector (OSTI)

......ionization detector (FIO) to various hydrocarbons hat been found to be proportional to powers of the concentration which ex- ceed unity In certain ranges. The sample elution rates at which this effect is observed and operating condi- tions employed correspond......

J.H. Bromly; P. Roga

1980-11-01T23:59:59.000Z

198

6 - Industrial Applications of Ionizing Radiation  

Science Journals Connector (OSTI)

The chapter summarizes the industrial applications of ionizing radiation. Ionizing radiation finds use in a variety of industrial applications such as wire and cable insulation, tire manufacturing, production of polymeric foams, heat-shrinkable films and tubings, curing of coatings, adhesives and composites, printing, and other technological development. It provides extensive information on EB process in wire and cable and tire technology. The chapter also provides discussion on EB process in the manufacture of polyolefin foams and heat-shrinkable materials. Detailed discussion on cross-linked PE pipes (PEX) including methods for production, irradiation, and its advantages, is presented. Other applications for ionizing radiation include sterilization of medical devices, hydrogels, radiation curing of polymeric composites, production of fluoroadditives, radiation-cured flexography, coatings, adhesives, paints, and printing inks. Keywords Ionizing radiation; tire manufacturing; wire and cable insulations; printing inks; polyolefin foams; heat-shrinkable materials; cross-linked PE pipes (PEX); hydrogels; flexography

Jiri George Drobny

2013-01-01T23:59:59.000Z

199

Electrical conductivity of nondegenerate, fully ionized plasmas  

Science Journals Connector (OSTI)

Within a virial expansion of the electrical conductivity of a fully ionized plasma, which takes into account many-particle effects, different limiting cases are considered. An appropriate interpolation formula is compared with experimental values.

G. Röpke and R. Redmer

1989-01-15T23:59:59.000Z

200

Studies on Neurosteroids XX. Liquid Chromatography—Tandem Mass Spectrometric Method for Simultaneous Determination of Testosterone and 5?-Dihydrotestosterone in Rat Brain and Serum  

Science Journals Connector (OSTI)

......LC) coupled with atmospheric pressure ionization...ionization (ESI) and atmospheric pressure chemical ionization...developed API technique, atmospheric pressure photoionization...methanol (2 mL), and water (2 mL) prior to use...between the nitrogen generator and the mass spectrometer......

Tatsuya Higashi; Yasuaki Ninomiya; Kazutake Shimada

2008-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Thermal treatment  

Science Journals Connector (OSTI)

Thermal treatment can be regarded as either a pre-treatment of waste prior to final disposal, or as a means of valorising waste by recovering energy. It includes both the burning of mixed MSW in municipal inciner...

Dr. P. White; Dr. M. Franke; P. Hindle

1995-01-01T23:59:59.000Z

202

Thermal Processes  

Energy.gov (U.S. Department of Energy (DOE))

Some thermal processes use the energy in various resources, such as natural gas, coal, or biomass, to release hydrogen, which is part of their molecular structure. In other processes, heat, in...

203

Determinations of Carbon Dioxide and Methane by Dual Catalyst Flame Ionization Chromatography and Nitrous Oxide by Electron Capture Chromatography  

Science Journals Connector (OSTI)

......thermistor has a low thermal mass and the circuit...and have longer thermal exchange times will...detectors such as the thermal conductivity detector...equatorial Pacific Ocean during a 24 day...Department of Energy. References Journal...Methanizer" catalytic converter. 5. W.E. Wentworth......

Ray F. Weiss

1981-12-01T23:59:59.000Z

204

MUCOOL: Ionization Cooling R&D  

NLE Websites -- All DOE Office Websites (Extended Search)

Laboratory Laboratory MUCOOL Muon Ionization Cooling R&D Welcome to the muon ionization cooling experimental R&D page. The MuCool collaboration has been formed to pursue the development of a muon ionization cooling channel for a high luminosity muon collider. For more information please contact Alan Bross (Spokesperson: bross@fnal.gov), Rick Fernow (BNL Contact person: fernow1@bnl.gov), or Mike Zisman (LBNL Contact person: mszisman@lbl.gov). General MUCOOL Telephone Book MUCOOL Notes MUCOOL Collaborating Institutes and Interests Useful Links Link to IIT MUCOOL page Meetings Muon Collaboration Friday Meetings Fermilab Muon Group Monday Meetings MTA RF Workshop (August 22, 2007 - Fermilab) Low Emittance Muon Collider Workshop (February 12-16, 2007, Fermilab) Low Emittance Muon Collider Workshop (February 6-10, 2006, Fermilab)

205

Weak interaction studies using resonance ionization spectroscopy  

SciTech Connect

Important developments in laser sources for the vacuum ultraviolet (VUV) region of the spectrum are making it possible to carry out resonance ionization of some of the noble gases. It has already been shown that xenon can be ionized in a two-photon allowed excitation from the ground state. Recently a new method of generating radiation by four-wave mixing in mercury vapor enables excitation of xenon in a one-photon resonance process. With these new laser sources we expect to have effective ionization volumes of 10/sup -3/ to 10/sup -2/ cm/sup 3/ for the cases of argon, krypton, and xenon. This has important consequences in weak interaction physics and environmental research.

Payne, M.G.; Hurst, G.S.

1982-01-01T23:59:59.000Z

206

HIGH-REDSHIFT METALS. II. PROBING REIONIZATION GALAXIES WITH LOW-IONIZATION ABSORPTION LINES AT REDSHIFT SIX  

SciTech Connect

We present a survey for low-ionization metal absorption line systems toward 17 QSOs at redshifts z{sub em} = 5.8-6.4. Nine of our objects were observed at high resolution with either Keck/HIRES or Magellan/MIKE, and the remainder at moderate resolution with Keck/ESI. The survey spans 5.3 < z{sub abs} < 6.4 and has a path length interval {Delta}X = 39.5 or {Delta}z = 8.0. In total we detect ten systems, five of which are new discoveries. The line-of-sight number density, l(X) = 0.25{sup +0.21}{sub -0.13} (95% confidence), is consistent with the combined number density at z {approx} 3 of damped Ly{alpha} systems (DLAs) and sub-DLAs, which comprise the main population of low-ionization systems at lower redshifts. This apparent lack of evolution may occur because low-ionization systems are hosted by lower-mass halos at higher redshifts, or because the mean cross section of low-ionization gas at a given halo mass increases with redshift due to the higher densities and lower ionizing background. The roughly constant number density notably contrasts with the sharp decline at z > 5.3 in the number density of highly ionized systems traced by C IV. The low-ionization systems at z {approx} 6 span a similar range of velocity widths as lower-redshift sub-DLAs but have significantly weaker lines at a given width. This may imply that the mass-metallicity relation of the host galaxies evolves toward lower metallicities at higher redshifts. These systems lack strong Si IV and C IV, which are common among lower-redshift DLAs and sub-DLAs. This is consistent, however, with a similar decrease in the metallicity of the low- and high-ionization phases, and does not necessarily indicate a lack of nearby, highly ionized gas. The high number density of low-ionization systems at z {approx} 6 suggests that we may be detecting galaxies below the current limits of i-dropout and Ly{alpha} emission galaxy surveys. These systems may therefore be the first direct probes of the 'typical' galaxies responsible for hydrogen reionization.

Becker, George D.; Calverley, Alexander P. [Kavli Institute for Cosmology and Institute of Astronomy, Madingley Road, Cambridge, CB3 0HA (United Kingdom); Sargent, Wallace L. W. [Palomar Observatory, California Institute of Technology, Pasadena, CA 91125 (United States); Rauch, Michael, E-mail: gdb@ast.cam.ac.uk, E-mail: acalver@ast.cam.ac.uk, E-mail: wws@astro.caltech.edu, E-mail: mr@obs.carnegiescience.edu [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

2011-07-10T23:59:59.000Z

207

Low pressure electrospray ionization system and process for effective transmission of ions  

DOE Patents (OSTI)

A system and method are disclosed that provide up to complete transmission of ions between coupled stages with low effective ion losses. A novel "interfaceless" electrospray ionization system is further described that operates the electrospray at a reduced pressure such that standard electrospray sample solutions can be directly sprayed into an electrodynamic ion funnel which provides ion focusing and transmission of ions into a mass analyzer.

Tang, Keqi (Richland, WA); Page, Jason S. (Kennewick, WA); Kelly, Ryan T. (Wet Richland, WA); Smith, Richard D. (Richland, WA)

2010-03-02T23:59:59.000Z

208

Low pressure electrospray ionization system and process for effective transmission of ions  

DOE Patents (OSTI)

Systems and methods that provide up to complete transmission of ions between coupled stages with low effective ion losses. An "interfaceless" electrospray ionization system is further described that operates an electrospray at a reduced pressure such that standard electrospray sample solutions can be directly sprayed into an electrodynamic ion funnel which provides ion focusing and transmission of ions into a mass analyzer. Furthermore, chambers maintained at different pressures can allow for more optimal operating conditions for an electrospray emitter and an ion guide.

Tang, Keqi (Richland, WA); Page, Jason S (Kennewick, WA); Kelly, Ryan T (West Richland, WA); Smith, Richard D (Richland, WA)

2012-05-08T23:59:59.000Z

209

Progress on a Cavity with Beryllium Walls for Muon Ionization Cooling Channel R&D.  

E-Print Network (OSTI)

WITH BERYLLIUM WALLS FOR MUON IONIZATION COOLING CHANNELNY 11973, USA Abstract The Muon Accelerator Program (MAP)an ionization cooling channel for muon beams. An ionization

Bowring, D.L.

2014-01-01T23:59:59.000Z

210

Compact time-of-flight mass spectrometer  

SciTech Connect

This paper describes a time-of-flight mass spectrometer developed for measuring the parameters of a pulsed hydrogen beam. The duration of an electron-beam current pulse in the ionizer of the mass spectrometer can be varied within 2-20 usec, the pulse electron current is 0.6 mA, and the electron energy is 250 eV. The time resolution of the mass spectrometer is determined by the repetition period of the electron-beam current pulses and is 40 usec. The mass spectrometer has 100% transmission in the direction of motion of molecular-beam particles. The dimension of the mass spectrometer is 7 cm in this direction. The mass resolution is sufficient for determination of the composition of the hydrogen beam.

Belov, A.S.; Kubalov, S.A.; Kuzik, V.F.; Yakushev, V.P.

1986-02-01T23:59:59.000Z

211

Composite scintillators for detection of ionizing radiation  

DOE Patents (OSTI)

Applicant's present invention is a composite scintillator having enhanced transparency for detecting ionizing radiation comprising a material having optical transparency wherein said material comprises nano-sized objects having a size in at least one dimension that is less than the wavelength of light emitted by the composite scintillator wherein the composite scintillator is designed to have selected properties suitable for a particular application.

Dai, Sheng (Knoxville, TN) [Knoxville, TN; Stephan, Andrew Curtis (Knoxville, TN) [Knoxville, TN; Brown, Suree S. (Knoxville, TN) [Knoxville, TN; Wallace, Steven A. (Knoxville, TN) [Knoxville, TN; Rondinone, Adam J [Knoxville, TN

2010-12-28T23:59:59.000Z

212

Muon Cooling via Ionization Andrea Kay Forget  

E-Print Network (OSTI)

1 Muon Cooling via Ionization Andrea Kay Forget Department of Physics, Wayne State University, Detroit, Michigan 48202 Dated: August 7, 2006 Muons only live a few microseconds before they ultimately, and laser cooling) cannot be used to properly cool muons that are being used in proposed accelerators

Cinabro, David

213

Studies of Anomalous Ionization Edgar Y. Choueiri  

E-Print Network (OSTI)

Laboratory (EPPDyL) Princeton University, Princeton NJ 08544. Hideo Okuda Princeton Plasma Physics LabStudies of Anomalous Ionization Edgar Y. Choueiri Electric Propulsion and Plasma Dynamics., Princeton University Princeton, NJ. 08544 AIAA Paper: AIAA-94-2465 Abstract In order to improve the accuracy

Choueiri, Edgar

214

High Sensitivity Combined with Extended Structural Coverage of Labile Compounds via Nanoelectrospray Ionization at Subambient Pressures  

SciTech Connect

Subambient pressure ionization with nanoelectrospray (SPIN) has proven to be effective in producing ions with high efficiency and transmitting them to low pressures for high sensitivity mass spectrometry (MS) analysis. Here we present evidence that not only does the SPIN source improve MS sensitivity but also allows for gentler ionization conditions. The gentleness of a conventional heated capillary electrospray ionization (ESI) source and the SPIN source was compared by the liquid chromatography mass spectrometry (LC-MS) analysis of colominic acid. Colominic acid is a mixture of sialic acid polymers of different lengths containing labile glycosidic linkages between monomer units necessitating a gentle ion source. By coupling the SPIN source with high resolution mass spectrometry and using advanced data processing tools, we demonstrate much extended coverage of sialic acid polymer chains as compared to using the conventional ESI source. Additionally we show that SPIN-LC-MS is effective in elucidating polymer features with high efficiency and high sensitivity previously unattainable by the conventional ESI-LC-MS methods. ?

Cox, Jonathan T.; Kronewitter, Scott R.; Shukla, Anil K.; Moore, Ronald J.; Smith, Richard D.; Tang, Keqi

2014-10-07T23:59:59.000Z

215

Detoxification of Salmonella typhimurium Lipopolysaccharide by Ionizing Radiation  

Science Journals Connector (OSTI)

...efficiency of ionizing radiation in detoxifying...decreased with doses above 1 Mrad...efficiency of ionizing radiation in detoxifying...decreased with doses above 1 Mrad...the visible range. After radiation, the general...radiation doses through 20...

Joseph J. Previte; Y. Chang; H. M. El-Bisi

1967-05-01T23:59:59.000Z

216

Oligonucleotide microarray analysis of low-dose ionizing radiation exposure  

Science Journals Connector (OSTI)

...health risk due to low-dose ionizing radiation is still debated. Functional...pathways that are induced by ionizing irradiation (IR...transcriptionally regulated by low-dose IR in occupationally...and showed different ranges of accumulated doses...

Paola Silingardi; Elena Morandi; Cinzia Severini; Daniele Quercioli; Monica Vaccari; Wolfango Horn; Maria Concetta Nucci; Vittorio Lodi; Francesco Violante; Sandro Grilli; and Annmaria Colacci

2007-05-01T23:59:59.000Z

217

Ionizing Radiation Activates the Nrf2 Antioxidant Response  

Science Journals Connector (OSTI)

...Scientific). Results Ionizing radiation does not activate ARE-reporter...determine if exposure to varying doses of ionizing radiation would activate the Nrf2-ARE pathway. The radiation dose range was extended below that used...

J. Tyson McDonald; Kwanghee Kim; Andrew J. Norris; Erina Vlashi; Tiffany M. Phillips; Chann Lagadec; Lorenza Della Donna; Josephine Ratikan; Heather Szelag; Lynn Hlatky; and William H. McBride

2010-11-01T23:59:59.000Z

218

AQUIFER THERMAL ENERGY STORAGE  

E-Print Network (OSTI)

using aquifers for thermal energy storage. Problems outlinedmatical Modeling of Thermal Energy Storage in Aquifers,"ings of Aquifer Thermal Energy Storage Workshop, Lawrence

Tsang, C.-F.

2011-01-01T23:59:59.000Z

219

Photo-Ionization and the Electrical Breakdown of Gases  

Science Journals Connector (OSTI)

25 June 1953 research-article Photo-Ionization and the Electrical Breakdown...theoretical investigation is made of the role of photo-ionization of the gas in the development...obtained experimentally. It is shown that photo-ionization can lead to electrical breakdown...

1953-01-01T23:59:59.000Z

220

Epidemiological Studies of Leukemia in Persons Exposed to Ionizing Radiation  

Science Journals Connector (OSTI)

...exposed to ionizing radiation, the author...the higher dose range regardless...low dose range, it is emphasized...possibility of radiation hazards existing at low doses should not...exposed to ionizing radiation...exposed to ionizing radiation, the author...the higher dose range regardless...

L. H. Hempelmann

1960-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Critical Behavior of Electron Impact Ionization of Atoms  

E-Print Network (OSTI)

Critical Behavior of Electron Impact Ionization of Atoms IMAD LADADWA,1,2 SABRE KAIS1 1 Department of the electron impact ionization for different atoms are calculated numerically in the Born approximation as a function of both the incident electron energy and the nuclear charge Z of the ionized atom. We show

Kais, Sabre

222

The mass  

Science Journals Connector (OSTI)

The mass of the charged Higgs boson at the 1-loop level is investigated, assuming the CP symmetry to be violated explicitly in the Higgs sector of the minimal supersymmetric standard model (MSSM). It is found that there is a parameter region of the MSSM where the presence of explicit CP violation in the Higgs sector yields negative radiative corrections to the charged Higgs boson mass. Thus, the charged Higgs boson in the MSSM may have as low a mass as 60 GeV at the 1-loop level, if the CP symmetry is violated. This lower bound may be improved by the Higgs search at LEP2, which imposes experimental constraints on the charged Higgs mass, as well as on the masses of the neutral Higgs bosons. Hence, LEP2 can constrain experimentally the charged Higgs mass to be not smaller than 109 GeV under our assumption. In addition, it sets 75 GeV as the lower bound on the mass of the lightest neutral Higgs boson, and 84 GeV for that of the next-to-lightest neutral Higgs boson.

Seung Woo Ham; Sun Kun Oh; Eun Jong Yoo; Hyun Kyu Lee

2001-01-01T23:59:59.000Z

223

Quantifying Uranium Isotope Ratios Using Resonance Ionization Mass Spectrometry: The Influence of Laser Parameters on Relative Ionization Probability  

E-Print Network (OSTI)

Schumann, K. Wendt, B. Bushaw, High-resolution triple-resonancefrom Schumann, et al. is the lack of a sharp resonance atresonance marked with an asterisk is described in the text. (Reproduced from Schumann,

Isselhardt, Brett Hallen

2011-01-01T23:59:59.000Z

224

E-Print Network 3.0 - assisted resonance ionization Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

ionization PADIACplasma43 Dielectricbarrierdischarge... Matrix-assisted ionization ... Source: Oak Ridge National Laboratory Fossil Energy Program Collection: Fossil Fuels 28...

225

Photo-Ionization of Molecules near Threshold  

Science Journals Connector (OSTI)

An orthogonalized Coulomb-wave method for the construction of continuum wave functions of molecules is described. Hydrogenic functions of definite angular momentum, which transform according to the irreducible representations of the point group of the molecule, are phenomenologically used as trial functions. Corrections to the trial functions are made by orthogonalizing them to charge rearrangement states of the molecule. The photo-ionization cross section is obtained by summing over the asymptotic angular-momentum quantum number. The method is exemplified by calculation of the photo-ionization cross sections of the ground and first excited states of the anthracene molecule in the range of 1.5 eV above threshold.

John P. Hernandez

1968-03-05T23:59:59.000Z

226

Photo-Auger ionization of lithiumlike ions  

Science Journals Connector (OSTI)

The photo-Auger ionization process is a higher-order contribution to the direct photoelectric effect in which photoexcitation of an inner-shell electron is followed by the emission of an Auger electron. The frequency-integrated photo-Auger ionization cross section for ions of the lithium isoelectronic sequence is calculated in the isolated resonance approximation. The effects of transitions into all accessible intermediate states are explicitly included. Results are compared with the frequency-integrated direct photoionization cross section. The relative contribution of the photo-Auger effect for three-electron ions is a maximum in the Ne(7 +) region, where it is of order 70% of the direct process.

K. J. LaGattuta and Yukap Hahn

1982-01-01T23:59:59.000Z

227

External ionization mechanisms for advanced thermionic converters  

SciTech Connect

This work investigates ion generation and recombination mechanisms in the cesium plasma as they pertain to the advanced mode thermionic energy converter. The changes in plasma density and temperature within the converter have been studied under the influence of several promising auxiliary ionization candidate sources. Three novel approaches of external cesium ion generation have been investigated in some detail, namely vibrationally excited N/sub 2/ as are energy source of ionization of Cs ions in a dc discharge, microwave power as a means of resonant sustenance of the cesium plasma, and ion generation in a pulse N/sub 2/-Cs mixture. The experimental data obtained and discussed in this work show that all three techniques - i.e. the non-LTE high-voltage pulsing, the energy transfer from vibrationally excited diatomic gases, and the external pumping with a microwave power - have considerable promise as schemes in auxiliary ion generation applicable to the advanced thermionic energy converter.

Hatziprokopiou, M.E.

1981-01-01T23:59:59.000Z

228

Photo-Ionization of Crystalline Anthracene  

Science Journals Connector (OSTI)

The photo-ionization spectra of the ground, first singlet, and first triplet states of crystalline anthracene are calculated assuming transitions to a simple continuum. The calculations neglect vibrational-overlap factors which will reduce the cross sections perhaps by as much as a factor of 10. Recombination is also neglected, and is blamed for discrepancies between the calculation and experiments which measure photo-currents. Kepler has reported a cross section of 2×10-19 cm2 from the first singlet, Courtens et al., one of 0.6×10-19; the calculation gives 6×10-18. Holzman et al. report 10-20 cm2 from the first triplet; the calculation gives 6×10-18. If one accounted for vibrational overlap and recombination (which will be larger in the second experiment, because of the smaller kinetic energy), the agreement would be good. The agreement is not so good with the magnitude of transitions from the ground state, though the energy dependence gives a good fit. The discrepancy may be due to the (neglected) influence of auto-ionizing states on the final-state wave functions. Based on a theory by Choi, the singlet exciton-exciton ionization rate constant is calculated to be 2×10-9 cm3 sec-1 (vibrations and recombination neglected) compared with Silver's experimental value of 0.8×10-10; again the agreement is good. Finally, the time needed for a photo-ionized electron to lose kinetic energy by exciting a triplet is calculated to be 10-9 sec or longer, so this mechanism is ruled out as an energy-loss process in comparison with the emission of optical vibrations, which has been estimated to take about 10-13 sec.

John P. Hernandez

1968-05-15T23:59:59.000Z

229

Ionization photophysics and spectroscopy of dicyanoacetylene  

SciTech Connect

Photoionization of dicyanoacetylene was studied using synchrotron radiation over the excitation range 8–25 eV, with photoelectron-photoion coincidence techniques. The absolute ionization cross-section and detailed spectroscopic aspects of the parent ion were recorded. The adiabatic ionization energy of dicyanoacetylene was measured as 11.80 ± 0.01 eV. A detailed analysis of the cation spectroscopy involves new aspects and new assignments of the vibrational components to excitation of the quasi-degenerate A{sup 2}?{sub g}, B{sup 2}?{sub g}{sup +} states as well as the C{sup 2}?{sub u}{sup +} and D{sup 2}?{sub u} states of the cation. Some of the structured autoionization features observed in the 12.4–15 eV region of the total ion yield spectrum were assigned to vibrational components of valence shell transitions and to two previously unknown Rydberg series converging to the D{sup 2}?{sub u} state of C{sub 4}N{sub 2}{sup +}. The appearance energies of the fragment ions C{sub 4}N{sup +}, C{sub 3}N{sup +}, C{sub 4}{sup +}, C{sub 2}N{sup +}, and C{sub 2}{sup +} were measured and their heats of formation were determined and compared with existing literature values. Thermochemical calculations of the appearance potentials of these and other weaker ions were used to infer aspects of dissociative ionization pathways.

Leach, Sydney, E-mail: Sydney.Leach@obspm.fr, E-mail: Martin.Schwell@lisa.u-pec.fr; Champion, Norbert [LERMA UMR CNRS 8112, Observatoire de Paris-Meudon, 5 place Jules-Jansen, 92195 Meudon (France)] [LERMA UMR CNRS 8112, Observatoire de Paris-Meudon, 5 place Jules-Jansen, 92195 Meudon (France); Schwell, Martin, E-mail: Sydney.Leach@obspm.fr, E-mail: Martin.Schwell@lisa.u-pec.fr; Bénilan, Yves; Fray, Nicolas; Gazeau, Marie-Claire [LISA UMR CNRS 7583, Université Paris-Est Créteil and Université Paris Diderot, Institut Pierre Simon Laplace, 61 Avenue du Général de Gaulle, 94010 Créteil (France)] [LISA UMR CNRS 7583, Université Paris-Est Créteil and Université Paris Diderot, Institut Pierre Simon Laplace, 61 Avenue du Général de Gaulle, 94010 Créteil (France); Garcia, Gustavo A.; Gaie-Levrel, François [Synchrotron SOLEIL, L’Orme des Merisiers, St. Aubin, B.P. 48, 91192 Gif-sur-Yvette Cedex (France)] [Synchrotron SOLEIL, L’Orme des Merisiers, St. Aubin, B.P. 48, 91192 Gif-sur-Yvette Cedex (France); Guillemin, Jean-Claude [Institut des Sciences Chimiques de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 (France)] [Institut des Sciences Chimiques de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 (France)

2013-11-14T23:59:59.000Z

230

Validation of the neutron and gamma fields in the JSI TRIGA reactor using in-core fission and ionization chambers  

Science Journals Connector (OSTI)

Abstract CEA developed fission chambers and ionization chambers were utilized at the JSI TRIGA reactor to measure neutron and gamma fields. The measured axial fission rate distributions in the reactor core are generally in good agreement with the calculated values using the Monte Carlo model of the reactor thus verifying both the computational model and the fission chambers. In future, multiple absolutely calibrated fission chambers could be used for more accurate online reactor thermal power monitoring.

Gašper Žerovnik; Tanja Kaiba; Vladimir Radulovi?; Anže Jazbec; Sebastjan Rupnik; Loïc Barbot; Damien Fourmentel; Luka Snoj

2015-01-01T23:59:59.000Z

231

Nanoelectrospray ion generation for high-throughput mass spectrometry using a micromachined ultrasonic ejector array  

SciTech Connect

Ultrasonic electrospray ionization (ESI) for high-throughput mass spectrometry is demonstrated using a silicon micromachined microarray. The device uses a micromachined ultrasonic atomizer operating in the 900 kHz-2.5 MHz range for droplet generation and a metal electrode in the fluid cavity for ionization. Since the atomization and ionization processes are separated, the ultrasonic ESI source shows the potential for operation at low voltages with a wide range of solvents in contrast with conventional capillary ESI technology. This is demonstrated using the ultrasonic ESI microarray to obtain the mass spectrum of a 10 {mu}M reserpine sample on a time of flight mass spectrometer with 197:1 signal-to-noise ratio at an ionization potential of 200 V.

Aderogba, S.; Meacham, J.M.; Degertekin, F.L.; Fedorov, A.G.; Fernandez, F.M. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2005-05-16T23:59:59.000Z

232

Transition of Iodine Analysis to Accelerator Mass Spectrometry  

SciTech Connect

This NA 22 funded research project investigated the transition of iodine isotopic analyses from thermal ionization mass spectrometry (TIMS) to an accelerator mass spectrometry (AMS) system. Previous work (Fiscal Year 2010) had demonstrated comparable data from TIMS and AMS. With AMS providing comparable data with improved background levels and vastly superior sample throughput, improvement in the sample extraction from environmental sample matrices was needed to bring sample preparation throughput closer to the operation level of the instrument. Previous research used an extraction chemistry that was not optimized for yield or refined for reduced labor to prove the principle. This research was done to find an extraction with better yield using less labor per sample to produce a sample ready for the AMS instrument. An extraction method using tetramethyl ammonium hydroxide (TMAH) was developed for removal of iodine species from high volume air filters. The TMAH with gentle heating was superior to the following three extraction methods: ammonium hydroxide aided by sonication, acidic and basic extraction aided by microwave, and ethanol mixed with sodium hydroxide. Taking the iodine from the extraction solvent to being ready for AMS analysis was accomplished by a direct precipitation, as well as, using silver wool to harvest the iodine from the TMAH. Portions of the same filters processed in FY 2010 were processed again with the improved extraction scheme followed by successful analysis by AMS at the Swiss Federal Institute of Technology. The data favorably matched the data obtained in 2010. The time required for analysis has been reduced over the aqueous extraction/AMS approach developed in FY 2010. For a hypothetical batch of 30 samples, the AMS methodology is about 10 times faster than the traditional gas phase chemistry and TIMS analysis. As an additional benefit, background levels for the AMS method are about 1000 times lower than TIMS. This results from the fundamental mechanisms of ionization in the AMS system and which produces a beneficial cleanup of molecular interferences. Continued clean operation of the extraction process was demonstrated through blank analysis included with all sample sets analyzed. INL work showed improvement on the first year’s demonstration of AMS vs. TIMS. An improved extraction of high volume air filters followed by isotopic analysis by AMS, can be used successfully to make iodine measurements with results comparable to those obtained by filter combustion and TIMS analysis. More progress on the conversion from an extract solution to an AMS sample ready for analysis is still needed. Although the preparation scheme through AMS is already at a higher performing thoughput than TIMS, the chemical preparation cannot match the instrument capability for number of samples per day without further development.

M. L. Adamic; J. E. Olson; D. D. Jenson; J. G. Eisenmenger; M. G. Watrous

2012-09-01T23:59:59.000Z

233

Thermo-chemical dynamics and chemical quasi-equilibrium of plasmas in thermal non-equilibrium  

SciTech Connect

We examine both processes of ionization by electron and heavy-particle impact in spatially uniform plasmas at rest in the absence of external forces. A singular perturbation analysis is used to study the following physical scenario, in which thermal relaxation becomes much slower than chemical reactions. First, electron-impact ionization is investigated. The dynamics of the system rapidly becomes close to a slow dynamics manifold that allows for defining a unique chemical quasi-equilibrium for two-temperature plasmas and proving that the second law of thermodynamics is satisfied. Then, all ionization reactions are taken into account simultaneously, leading to a surprising conclusion: the inner layer for short time scale (or time boundary layer) directly leads to thermal equilibrium. Global thermo-chemical equilibrium is reached within a short time scale, involving only chemical reactions, even if thermal relaxation through elastic collisions is assumed to be slow.

Massot, Marc [Laboratoire EM2C, UPR 288 CNRS - Ecole Centrale Paris (France); Graille, Benjamin [Laboratoire de Mathematiques d'Orsay, UMR 8628 CNRS - Universite Paris-Sud (France); Magin, Thierry E. [Aeronautics and Aerospace Department, von Karman Institute for Fluid Dynamics (Belgium)

2011-05-20T23:59:59.000Z

234

Cornell University Thermal Comfort Report  

NLE Websites -- All DOE Office Websites (Extended Search)

Thermal Comfort Thermal Comfort Thermal comfort in the CUSD home is a top priority for our team. Accordingly, we designed a redundant HVAC system that would carefully manage the comfort of our decathletes and guests throughout the competition and the life of the house. The CUSD home's HVAC system was optimized for Washington, DC, with the cold Ithaca climate in mind. Our design tools included a schematic energy-modeling interface called TREAT, which was built off of the SuNREL platform. TREAT was used to passively condition the space. Our schematic energy modeling helped us properly size window areas, overhangs, and building mass distribution. We used a computation fluid dynamics (CFD) package called AirPak, to refine our design. The home was modeled in both

235

Electromagnetic polarization in partially ionized plasmas with strong magnetic fields and neutron star atmosphere models  

E-Print Network (OSTI)

Polarizability tensor of a strongly magnetized plasma and the polarization vectors and opacities of normal electromagnetic waves are studied for the conditions typical of neutron star atmospheres, taking account of partial ionization effects. Vacuum polarization is also included using a new set of fitting formulae that are accurate for wide range of field strengths. The full account of the coupling of the quantum mechanical structure of the atoms to their center-of-mass motion across the magnetic field is shown to be crucial for the correct evaluation of the polarization properties and opacities of the plasma. The self-consistent treatment of the polarizability and absorption coefficients proves to be necessary if the ionization degree of the plasma is low, which can occur in the atmospheres of cool or ultramagnetized neutron stars. Atmosphere models and spectra are presented to illustrate the importance of such self-consistent treatment.

A. Y. Potekhin; Dong Lai; G. Chabrier; W. C. G. Ho

2004-05-20T23:59:59.000Z

236

X-RAY REFLECTED SPECTRA FROM ACCRETION DISK MODELS. III. A COMPLETE GRID OF IONIZED REFLECTION CALCULATIONS  

SciTech Connect

We present a new and complete library of synthetic spectra for modeling the component of emission that is reflected from an illuminated accretion disk. The spectra were computed using an updated version of our code XILLVER that incorporates new routines and a richer atomic database. We offer in the form of a table model an extensive grid of reflection models that cover a wide range of parameters. Each individual model is characterized by the photon index {Gamma} of the illuminating radiation, the ionization parameter {xi} at the surface of the disk (i.e., the ratio of the X-ray flux to the gas density), and the iron abundance A{sub Fe} relative to the solar value. The ranges of the parameters covered are 1.2 {<=} {Gamma} {<=} 3.4, 1 {<=} {xi} {<=} 10{sup 4}, and 0.5 {<=} A{sub Fe} {<=} 10. These ranges capture the physical conditions typically inferred from observations of active galactic nuclei, and also stellar-mass black holes in the hard state. This library is intended for use when the thermal disk flux is faint compared to the incident power-law flux. The models are expected to provide an accurate description of the Fe K emission line, which is the crucial spectral feature used to measure black hole spin. A total of 720 reflection spectra are provided in a single FITS file (http://hea-www.cfa.harvard.edu/{approx}javier/xillver/) suitable for the analysis of X-ray observations via the atable model in XSPEC. Detailed comparisons with previous reflection models illustrate the improvements incorporated in this version of XILLVER.

Garcia, J.; McClintock, J. E. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Dauser, T.; Wilms, J.; Eikmann, W. [Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Sternwartstr. 7, D-96049 Bamberg (Germany); Reynolds, C. S. [Department of Astronomy, University of Maryland, College Park, MD (United States); Kallman, T. R., E-mail: javier@head.cfa.harvard.edu, E-mail: jem@cfa.harvard.edu, E-mail: chris@astro.umd.edu, E-mail: thomas.dauser@sternwarte.uni-erlangen.de, E-mail: joern.wilms@sternwarte.uni-erlangen.de, E-mail: wiebke.eikmann@sternwarte.uni-erlangen.de, E-mail: timothy.r.kallman@nasa.gov [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2013-05-10T23:59:59.000Z

237

Removal of submicron particles using a carbon fiber ionizer-assisted medium air filter in a heating, ventilation, and air-conditioning (HVAC) system  

Science Journals Connector (OSTI)

Laboratory tests of particle removal were performed with a pair of carbon fiber ionizers installed upstream of a glass fiber air filter. For air flow face velocities of 0.4, 0.6, and 0.8 m/s, the overall particle removal efficiencies of the filter for all submicron particles were 17%, 16%, and 14%, respectively, when the ionizers were not turned on. These values increased to 27%, 23%, and 19%, respectively, when the ionizers were used to generate ions of 6.0 × 109 ions/cm3 in concentration. The carbon fiber ionizers were then installed in front of a glass fiber air filter located in a heating, ventilation, and air-conditioning (HVAC) system. Field tests were performed in a test office room with a total indoor particle concentration of 2.2 × 104 particles/cm3. When the flow rate was 75 cubic meters per hour (CMH), the steady-state values of the total indoor particle concentrations using the glass fiber air filter with and without ionizers decreased to 0.87 × 104 particles/cm3 and 1.15 × 104 particles/cm3, respectively, resulting in a 25% decrease of the ionizer effect. When the operation flow rate was increased to 115 and 150 CMH, the effect of the ionizer decreased to 19% and 17%, respectively. These experimental data match the results calculated using a mass-balance model whose parameters were determined from laboratory tests.

Jae Hong Park; Ki Young Yoon; Jungho Hwang

2011-01-01T23:59:59.000Z

238

Ionization Chambers in the FLASH Dump Line  

E-Print Network (OSTI)

. 7, 2010FLASH Seminar, Dec. 7, 2010 BPM 13DUMP Dump Line Upgrade 2009Dump Line Upgrade 2009 BPM 9DUMP BPM 5DUMP Toroid 9DUMP OTR screen 9DUMP BLM 14DUMP BLM 13.1DUMP 13.2DUMP BLM 9DUMP BLM 6DUMP BLM 1.1DUMP 1.2DUMP BPM 10DUMP BPM 16DUMP 8 x BHM 16DUMP BLM 14R.DUMP 14L.DUMP 14U.DUMP 14D.DUMP Ionization

239

Resonance ionization detection of combustion radicals  

SciTech Connect

Fundamental research on the combustion of halogenated organic compounds with emphasis on reaction pathways leading to the formation of chlorinated aromatic compounds and the development of continuous emission monitoring methods will assist in DOE efforts in the management and disposal of hazardous chemical wastes. Selective laser ionization techniques are used in this laboratory for the measurement of concentration profiles of radical intermediates in the combustion of chlorinated hydrocarbon flames. A new ultrasensitive detection technique, made possible with the advent of tunable VUV laser sources, enables the selective near-threshold photoionization of all radical intermediates in premixed hydrocarbon and chlorinated hydrocarbon flames.

Cool, T.A. [Cornell Univ., Ithaca, NY (United States)

1993-12-01T23:59:59.000Z

240

(Resonance ionization spectroscopy and its applications)  

SciTech Connect

The field of Resonance Ionization Spectroscopy grew out of work done in the Photophysics Group at Oak Ridge National Laboratory. As one of the original developers of this field the traveler has continued to attend this meeting on a regular basis. The traveler was originally asked to present an invited talk and to present part of a short course offered to graduate students attending the conference. Subsequently, the traveler was also asked to chair a session and to be a judge of the students papers entered in a contest for a $1000 first prize.

Payne, M.G.

1990-10-05T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

MAINTAINING HIGH RESOLUTION MASS SPECTROMETRY CAPABILITIES FOR NATIONAL NUCLEAR SECURITY ADMINISTRATION APPLICATIONS  

SciTech Connect

The Department of Energy (DOE) National Nuclear Security Administration (NNSA) has a specialized need for analyzing low mass gas species at very high resolutions. The currently preferred analytical method is electromagnetic sector mass spectrometry. This method allows the NNSA Nuclear Security Enterprise (NSE) to resolve species of similar masses down to acceptable minimum detection limits (MDLs). Some examples of these similar masses are helium-4/deuterium and carbon monoxide/nitrogen. Through the 1980s and 1990s, there were two vendors who supplied and supported these instruments. However, with declining procurements and down turns in the economy, the supply of instruments, service and spare parts from these vendors has become less available, and in some cases, nonexistent. The largest NSE user of this capability is the Savannah River Site (SRS), located near Aiken, South Carolina. The Research and Development Engineering (R&DE) Group in the Savannah River National Laboratory (SRNL) investigated the areas of instrument support that were needed to extend the life cycle of these aging instruments. Their conclusions, as to the focus areas of electromagnetic sector mass spectrometers to address, in order of priority, were electronics, software and hardware. Over the past 3-5 years, the R&DE Group has designed state of the art electronics and software that will allow high resolution legacy mass spectrometers, critical to the NNSA mission, to be operated for the foreseeable future. The funding support for this effort has been from several sources, including the SRS Defense Programs, NNSA Readiness Campaign, Pantex Plant and Sandia National Laboratory. To date, electronics systems have been upgraded on one development system at SRNL, two production systems at Pantex and one production system at Sandia National Laboratory. An NSE working group meets periodically to review strategies going forward. The R&DE Group has also applied their work to the electronics for a Thermal Ionization Mass Spectrometer (TIMS) instrument, which applies a similar mass spectrometric technology for resolving high mass isotopes, such as plutonium and uranium. Due to non-compete clauses for DOE, all work has been performed and applied to instruments which are obsolete and are no longer supported by the original vendor.

Wyrick, S.; Cordaro, J.; Reeves, G.; Mcintosh, J.; Mauldin, C.; Tietze, K.; Varble, D.

2011-06-06T23:59:59.000Z

242

Seasonal thermal energy storage  

SciTech Connect

This report describes the following: (1) the US Department of Energy Seasonal Thermal Energy Storage Program, (2) aquifer thermal energy storage technology, (3) alternative STES technology, (4) foreign studies in seasonal thermal energy storage, and (5) economic assessment.

Allen, R.D.; Kannberg, L.D.; Raymond, J.R.

1984-05-01T23:59:59.000Z

243

Dielectric liquid ionization chambers for detecting fast neutrons  

E-Print Network (OSTI)

Three ionization chambers with different geometries have been constructed and filled with dielectric liquids for detection of fast neutrons. The three dielectric liquids studied were Tetramethylsilane (TMS), Tetramethylpentane ...

Boyd, Erin M

2008-01-01T23:59:59.000Z

244

IONIZATION OF EXTRASOLAR GIANT PLANET ATMOSPHERES  

SciTech Connect

Many extrasolar planets orbit close in and are subject to intense ionizing radiation from their host stars. Therefore, we expect them to have strong, and extended, ionospheres. Ionospheres are important because they modulate escape in the upper atmosphere and can modify circulation, as well as leave their signatures, in the lower atmosphere. In this paper, we evaluate the vertical location Z{sub I} and extent D{sub I} of the EUV ionization peak layer. We find that Z{sub I{approx}}1-10 nbar-for a wide range of orbital distances (a = 0.047-1 AU) from the host star-and D{sub I}/H{sub p{approx}}>15, where H{sub p} is the pressure scale height. At Z{sub I}, the plasma frequency is {approx}80-450 MHz, depending on a. We also study global ion transport, and its dependence on a, using a three-dimensional thermosphere-ionosphere model. On tidally synchronized planets with weak intrinsic magnetic fields, our model shows only a small, but discernible, difference in electron density from the dayside to the nightside ({approx}9 x 10{sup 13} m{sup -3} to {approx}2 x 10{sup 12} m{sup -3}, respectively) at Z{sub I}. On asynchronous planets, the distribution is essentially uniform. These results have consequences for hydrodynamic modeling of the atmospheres of close-in extrasolar giant planets.

Koskinen, Tommi T. [Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd., Tucson, AZ (United States); Cho, James Y-K. [Astronomy Unit, School of Mathematical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom); Achilleos, Nicholas; Aylward, Alan D., E-mail: tommi@lpl.arizona.ed [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

2010-10-10T23:59:59.000Z

245

Thermal unobtainiums? The perfect thermal conductor and  

E-Print Network (OSTI)

contribute to thermal resistance · Isotopically pure diamond has highest thermal conductivity of any material materials: disordered layered crystals Conclude with some thoughts on promising, high-risk, research even in a computer model. #12;Thermal resistance is created by Umklapp scattering (U

Braun, Paul

246

Progress on a Cavity with Beryllium Walls for Muon Ionization Cooling Channel R&D.  

SciTech Connect

The Muon Accelerator Program (MAP) collaboration is working to develop an ionization cooling channel for muon beams. An ionization cooling channel requires the operation of high-gradient, normal-conducting RF cavities in multi-Tesla solenoidal magnetic fields. However, experiments conducted at Fermilab?s MuCool Test Area (MTA) show that increasing the solenoidal field strength reduces the maximum achievable cavity gradient. This gradient limit is characterized by an RF breakdown process that has caused significant damage to copper cavity interiors. The damage may be caused by field-emitted electrons, focused by the solenoidal magnetic field onto small areas of the inner cavity surface. Local heating may then induce material fatigue and surface damage. Fabricating a cavity with beryllium walls would mitigate this damage due to beryllium?s low density, low thermal expansion, and high electrical and thermal conductivity. We address the design and fabrication of a pillbox RF cavity with beryllium walls, in order to evaluate the performance of high-gradient cavities in strong magnetic fields.

Bowring, D.L.; DeMello, A.J.; Lambert, A.R.; Li, D.; Virostek,, S.; Zisman, M.; Kaplan, D.; Palmer, R.B.

2012-05-20T23:59:59.000Z

247

Hybrid quadrupole mass filter/quadrupole ion trap/time-of-flight-mass spectrometer for infrared multiple photon dissociation spectroscopy of mass-selected ions  

SciTech Connect

We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photon dissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources, an electrospray ionization source, as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection, a reduced pressure ({approx}10{sup -5} Torr) quadrupole ion trap (QIT) for OPO irradiation, and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarily increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay, the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study, we implemented this setup in the study of protonated tryptophan, TrpH{sup +}, as well as collision-induced dissociation products of this protonated amino acid [W. K. Mino, Jr., K. Gulyuz, D. Wang, C. N. Stedwell, and N. C. Polfer, J. Phys. Chem. Lett. 2, 299 (2011)]. Here, we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.

Gulyuz, Kerim; Stedwell, Corey N.; Wang Da; Polfer, Nick C. [Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611 (United States)

2011-05-15T23:59:59.000Z

248

Hybrid quadrupole mass filter/quadrupole ion trap/time-of-flight-mass spectrometer for infrared multiple photon dissociation spectroscopy of mass-selected ions  

Science Journals Connector (OSTI)

We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photondissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources an electrospray ionization source as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection a reduced pressure (?10?5 Torr) quadrupoleion trap (QIT) for OPOirradiation and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarily increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study we implemented this setup in the study of protonated tryptophan TrpH+ as well as collision-induced dissociation products of this protonated amino acid[W. K. Mino Jr. K. Gulyuz D. Wang C. N. Stedwell and N. C. Polfer J. Phys. Chem. Lett.2 299 (2011)]. Here we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.

Kerim Gulyuz; Corey N. Stedwell; Da Wang; Nick C. Polfer

2011-01-01T23:59:59.000Z

249

Thermal Control & System Integration  

Energy.gov (U.S. Department of Energy (DOE))

The thermal control and system integration activity focuses on issues such as the integration of motor and power control technologies and the development of advanced thermal control technologies....

250

Colliding Stellar Wind Models with Nonequilibrium Ionization: X-rays from WR 147  

E-Print Network (OSTI)

The effects of nonequilibrium ionization are explicitly taken into account in a numerical model which describes colliding stellar winds (CSW) in massive binary sytems. This new model is used to analyze the most recent X-ray spectra of the WR+OB binary system WR 147. The basic result is that it can adequately reproduce the observed X-ray emission (spectral shape, observed flux) but some adjustment in the stellar wind parameters is required. Namely, (i) the stellar wind velocities must be higher by a factor of 1.4 - 1.6; (ii) the mass loss must be reduced by a factor of ~ 2. The reduction factor for the mass loss is well within the uncertainties for this parameter in massive stars, but given the fact that the orbital parameters (e.g., inclination angle and eccentricity) are not well constrained for WR 147, even smaller corrections to the mass loss might be sufficient. Only CSW models with nonequilibrium ionization and equal (or nearly equal) electron and ion postshock temperature are successful. Therefore, the analysis of the X-ray spectra of WR 147 provides evidence that the CSW shocks in this object must be collisionless.

Svetozar A. Zhekov

2007-09-11T23:59:59.000Z

251

ARM - Evaluation Product - Multispectral Thermal Imager (MTI)  

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsMultispectral Thermal Imager (MTI) ProductsMultispectral Thermal Imager (MTI) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Multispectral Thermal Imager (MTI) 2000.10.01 - 2003.05.02 Site(s) NSA SGP General Description The Multispectral Thermal Imager is a space-based research and development project sponsored by the U.S. Department of Energy (DOE), Office of Nonproliferation and National Security. MTI's primary objective is to demonstrate advanced multispectral and thermal imaging, image processing, and associated technologies that could be used in future systems for detecting and characterizing facilities producing weapons of mass destruction. However, ARM and the MTI have an arrangement that allows ARM to receive MTI images.

252

Star formation, metallicity gradient and ionized gas: clues to the formation of the elliptical galaxies NGC6868 and NGC5903  

E-Print Network (OSTI)

The stellar population, metallicity distribution and ionized gas in the elliptical galaxies NGC 6868 and NGC 5903 are investigated in this paper by means of long-slit spectroscopy and stellar population synthesis. Lick indices in both galaxies present a negative gradient indicating an overabundance of Fe, Mg, Na and TiO in the central parts with respect to the external regions. Concerning the emitting gas conspicuously detected in NGC 6868, we test three hypotheses as ionizing source: an H II region, post-AGB stars and an Active Galactic Nucleus (AGN). Diagnostic diagrams involving the ratios $[NII]_{\\lambda6584}/H\\alpha$, $[OI]_{\\lambda6300}/H\\alpha$ and $[SII]_{\\lambda6717,31}/H\\alpha$, indicate that values measured in the central region of NGC 6868 are typical of LINERs. Together with the stellar population synthesis, this result suggests that the main source of gas ionization in NGC 6868 is non-thermal, produced by a low-luminosity AGN, probably with some contribution of shocks to explain ionization at distances of $\\sim3.5$ kpc from the nucleus.

Mauro G. Rickes; Miriani G. Pastoriza; Charles Bonatto

2007-11-22T23:59:59.000Z

253

1. Introduction Alanine-based ionizing radiation dosimetry is firmly  

E-Print Network (OSTI)

1. Introduction Alanine-based ionizing radiation dosimetry is firmly woven into the fabric of high-dose System and Its Implications in High-Dose Ionizing Radiation Metrology Volume 113 Number 2 March.g., radiochromic dosimetry). From the NMI's perspective, the broad absorbed- dose range of the alanine system

254

Electron Capture in a Fully Ionized Plasma  

E-Print Network (OSTI)

Properties of fully ionized water plasmas are discussed including plasma charge density oscillations and the screening of the Coulomb law especially in the dilute classical Debye regime. A kinetic model with two charged particle scattering events determines the transition rate per unit time for electron capture by a nucleus with the resulting nuclear transmutations. Two corrections to the recent Maiani et al. calculations are made: (i) The Debye screening length is only employed within its proper domain of validity. (ii) The WKB approximation employed by Maiani in the long De Broglie wave length limit is evidently invalid. We replace this incorrect approximation with mathematically rigorous Calogero inequalities in order to discuss the scattering wave functions. Having made these corrections, we find a verification for our previous results based on condensed matter electro-weak quantum field theory for nuclear transmutations in chemical batteries.

A. Widom; J. Swain; Y. N. Srivastava

2014-09-17T23:59:59.000Z

255

Photo-Ionization of the Hydrogen Molecule  

Science Journals Connector (OSTI)

One-center wave functions are employed to investigate the photo-ionization of the hydrogen molecule from its ground state X(1s??g1+), from 700 to 300 Å. It is assumed that the residual ion is left in its ground state, and the free electron is in a p? or p? orbital. Using the one-center wave functions for H2+ for the internuclear distance equal to 1. 4a0, the free-electron wave functions are obtained by solving the integrodifferential equations in exchange and polarized-orbital approximations. The oscillator strengths obtained in the polarized-orbital approximation are found to be in satisfactory agreement with the experimental data.

S. P. Khare

1968-09-05T23:59:59.000Z

256

A hierarchy of diffusion models for partially ionized plasmas. Isabelle Choquet  

E-Print Network (OSTI)

. These plasmas are the following electrical discharges: a thermal arc discharge, glow discharges in local thermo (or flow). Keywords: Arc discharge, glow discharge, electron flow, gas mixture, disparate masses, im, the electric discharge in a gas, or gas discharge. Various electric discharges exist and produce plasma

Paris-Sud XI, Université de

257

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation  

NLE Websites -- All DOE Office Websites (Extended Search)

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters composed of argon (Ar) shells and xenon (Xe) cores. The clusters were site-selectively ionized (i.e, ionization took place either in the xenon core or in the argon shell). Using a high-resolution photoelectron-ion coincidence technique at ALS Beamlines 10.0.1 and 11.0.2, the researchers concluded that charge-transfer processes and fragmentation dynamics are strongly influenced by the environment of the initially ionized atoms.

258

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation  

NLE Websites -- All DOE Office Websites (Extended Search)

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters composed of argon (Ar) shells and xenon (Xe) cores. The clusters were site-selectively ionized (i.e, ionization took place either in the xenon core or in the argon shell). Using a high-resolution photoelectron-ion coincidence technique at ALS Beamlines 10.0.1 and 11.0.2, the researchers concluded that charge-transfer processes and fragmentation dynamics are strongly influenced by the environment of the initially ionized atoms.

259

Laser plasma formation assisted by ultraviolet pre-ionization  

SciTech Connect

We present experimental and modeling studies of air pre-ionization using ultraviolet (UV) laser pulses and its effect on laser breakdown of an overlapped near-infrared (NIR) pulse. Experimental studies are conducted with a 266?nm beam (fourth harmonic of Nd:YAG) for UV pre-ionization and an overlapped 1064?nm NIR beam (fundamental of Nd:YAG), both having pulse duration of ?10?ns. Results show that the UV beam produces a pre-ionized volume which assists in breakdown of the NIR beam, leading to reduction in NIR breakdown threshold by factor of >2. Numerical modeling is performed to examine the ionization and breakdown of both beams. The modeled breakdown threshold of the NIR, including assist by pre-ionization, is in reasonable agreement with the experimental results.

Yalin, Azer P., E-mail: ayalin@engr.colostate.edu; Dumitrache, Ciprian [Department of Mechanical Engineering, Colorado State University, Fort Collins, Colorado 80523 (United States); Wilvert, Nick [Sandia Laboratory, Albuquerque, New Mexico 87123 (United States); Joshi, Sachin [Cummins Inc., Columbus, Indiana 47201 (United States); Shneider, Mikhail N. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States)

2014-10-15T23:59:59.000Z

260

Near-threshold positron impact ionization of hydrogen  

SciTech Connect

The hyperspherical hidden crossing method (HHCM) is used to investigate positron impact ionization of hydrogen near threshold. An important feature of this method is that it can provide valuable insight into scattering processes. In the calculation of positron-hydrogen ionization, the adiabatic Hamiltonian is expanded about the Wannier saddle point; anharmonic corrections are treated perturbatively. The S-wave results are consistent with the Wannier threshold law and with the extended threshold law that was previously derived using the HHCM. We have extended the previous HHCM calculation to higher angular momenta L and have calculated the absolute ionization cross-section for L = 0, 1 and 2. The HHCM calculation confirms that the S-wave ionization cross-section is small and provides the reason why it is small. The HHCM ionization cross-section (summed over the lowest partial waves) is compared with a convergent close-coupling calculation, a 33-state close-coupling calculation and experimental data.

Macek, Joseph H [ORNL; Ward, S.J. [University of North Texas; Jansen, Krista [University of North Texas; Shertzer, J. [College Holy Cross, Worcester, MA

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Thermal Management of Solar Cells  

E-Print Network (OSTI)

a better thermal conductance and when ceramic particles areor ceramic fillers that enhances thermal conductivity. Solid

Saadah, Mohammed Ahmed

2013-01-01T23:59:59.000Z

262

Ultra-low Q values for neutrino mass measurements  

SciTech Connect

We investigate weak nuclear decays with extremely small kinetic energy release (Q value) and thus extremely good sensitivity to the absolute neutrino mass scale. In particular, we consider decays into excited daughter states, and we show that partial ionization of the parent atom can help to tune Q values to << 1 keV. We discuss several candidate isotopes undergoing {beta}{sup {+-}}, bound state {beta}, or electron capture decay, and come to the conclusion that a neutrino mass measurement using low-Q decays might only be feasible if no ionization is required, and if future improvements in isotope production technology, nuclear mass spectroscopy, and atomic structure calculations are possible. Experiments using ions, however, are extremely challenging due to the large number of ions that must be stored. New precision data on nuclear excitation levels could help to identify further isotopes with low-Q decay modes and possibly less challenging requirements.

Kopp, Joachim; /Heidelberg, Max Planck Inst. /Fermilab; Merle, Alexander; /Heidelberg, Max Planck Inst.

2009-11-01T23:59:59.000Z

263

Escherichia coli Genes and Pathways Involved in Surviving Extreme Exposure to Ionizing Radiation  

Science Journals Connector (OSTI)

...doses of ionizing radiation does not depend on...the effects of high doses of ionizing radiation (IR). The repair...IR resistance. A range of modern screening...survive increasing doses of ionizing radiation in comparison to...

Rose T. Byrne; Stefanie H. Chen; Elizabeth A. Wood; Eric L. Cabot; Michael M. Cox

2014-07-21T23:59:59.000Z

264

Backward Raman amplification in a partially ionized gas A. A. Balakin,1  

E-Print Network (OSTI)

was accessed 10,11 . The experimental success was achieved using a gas jet of propane, subse- quently ionized of propane opens up the question of coupling in a partially ionized gas. Any additional ionization during

265

Interface for liquid chromatograph-mass spectrometer  

DOE Patents (OSTI)

A moving belt interface for real-time, high-performance liquid chromatograph (HPLC)/mass spectrometer (MS) analysis which strips away the HPLC solvent as it emerges from the end of the HPLC column and leaves a residue suitable for mass-spectral analysis. The interface includes a portable, stand-alone apparatus having a plural stage vacuum station, a continuous ribbon or belt, a drive train magnetically coupled to an external drive motor, a calibrated HPLC delivery system, a heated probe tip and means located adjacent the probe tip for direct ionization of the residue on the belt. The interface is also capable of being readily adapted to fit any mass spectrometer.

Andresen, Brian D. (Pleasanton, CA); Fought, Eric R. (Livermore, CA)

1989-01-01T23:59:59.000Z

266

Interface for liquid chromatograph-mass spectrometer  

DOE Patents (OSTI)

A moving belt interface is described for real-time, high-performance liquid chromatograph (HPLC)/mass spectrometer (MS) analysis which strips away the HPLC solvent as it emerges from the end of the HPLC column and leaves a residue suitable for mass-spectral analysis. The interface includes a portable, stand-alone apparatus having a plural stage vacuum station, a continuous ribbon or belt, a drive train magnetically coupled to an external drive motor, a calibrated HPLC delivery system, a heated probe tip and means located adjacent the probe tip for direct ionization of the residue on the belt. The interface is also capable of being readily adapted to fit any mass spectrometer. 8 figs.

Andresen, B.D.; Fought, E.R.

1989-09-19T23:59:59.000Z

267

Mass and fans in attached sunspaces  

SciTech Connect

The effect of thermal storage mass on the performance of an attached sunspace is investigated for a particular design in Boston. Mass in the sunspace and in the adjoining building are compared. Performance is evaluated in terms of temperature conditions in the sunspace and delivery of useful solar heat to the adjoining building. The dependence of the results on the manner of heat delivery is studied. Both natural convection and fan-forced air flow are included.

Jones, R.W.; McFarland, R.D.; Lazarus, G.S.

1982-01-01T23:59:59.000Z

268

E-Print Network 3.0 - assisted laser ionization Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

Summary: of a high power pulsed far-infrared laser. Furthermore, impurity ionization with terahertz radiation can... of ionization capture processes due to the Poole-Frenkel...

269

E-Print Network 3.0 - activities involving ionizing Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

Collection: Physics 62 Magnetic field effect on tunnel ionization of deep impurities by terahertz radiation S.D. Ganichev1 Summary: Magnetic field effect on tunnel ionization of...

270

Mass Flows in Cometary UCHII Regions  

E-Print Network (OSTI)

High spectral and spatial resolution, mid-infrared fine structure line observations toward two ultracompact HII (UCHII) regions (G29.96 -0.02 and Mon R2) allow us to study the structure and kinematics of cometary UCHII regions. In our earlier study of Mon R2, we showed that highly organized mass motions accounted for most of the velocity structure in that UCHII region. In this work, we show that the kinematics in both Mon R2 and G29.96 are consistent with motion along an approximately paraboloidal shell. We model the velocity structure seen in our mapping data and test the stellar wind bow shock model for such paraboloidal like flows. The observations and the simulation indicate that the ram pressures of the stellar wind and ambient interstellar medium cause the accumulated mass in the bow shock to flow along the surface of the shock. A relaxation code reproduces the mass flow's velocity structure as derived by the analytical solution. It further predicts that the pressure gradient along the flow can accelerate ionized gas to a speed higher than that of the moving star. In the original bow shock model, the star speed relative to the ambient medium was considered to be the exit speed of ionized gas in the shell.

Qing-Feng Zhu; John H. Lacy; Daniel T. Jaffe; Thomas K. Greathouse; Matthew J. Richter

2005-06-06T23:59:59.000Z

271

Plasmadynamics and ionization kinetics of thermionic energy conversion  

SciTech Connect

To reduce the plasma arc-drop, thermionic energy conversion is studied with both analytical and numerical tools. Simplifications are made in both the plasmadynamic and ionization-recombination theories. These are applied to a scheme proposed presently using laser irradiation to enhance the ionization kinetics of the thermionic plasma and thereby reduce the arc-drop. It is also predicted that it is possible to generate the required laser light from a thermionic-type cesium plasma. The analysis takes advantage of theoretical simplifications derived for the ionization-recombination kinetics. It is shown that large laser ionization enhancements can occur and that collisional cesium recombination lasing is expected. To complement the kinetic theory, a numerical method is developed to solve the thermionic plasma dynamics. To combine the analysis of ionization-recombination kinetics with the plasma dynamics of thermionic conversion, a finite difference computer program is constructed. It is capable of solving for both unsteady and steady thermionic converter behavior including possible laser ionization enhancement or atomic recombination lasing. A proposal to improve thermionic converter performance using laser radiation is considered. In this proposed scheme, laser radiation impinging on a thermionic plasma enhances the ionization process thereby raising the plasma density and reducing the plasma arc-drop. A source for such radiation may possibly be a cesium recombination laser operating in a different thermionic converter. The possibility of this being an energy efficient process is discussed. (WHK)

Lawless, J.L. Jr.; Lam, S.H.

1982-02-01T23:59:59.000Z

272

Determination of boron traces in rye grass BCR 281 by isotope dilution mass spectrometry  

Science Journals Connector (OSTI)

A method for the isotope dilution mass spectrometric (IDMS) determination of boron in rye grass at the 5 ?g...?1 level has been developed. The mass spectrometric measurements are performed using negative thermal ...

A. Lamberty; V. Holland; A. Verbruggen…

1988-01-01T23:59:59.000Z

273

Linear Electric Field Time-Of-Flight Ion Mass Spectrometers  

NLE Websites -- All DOE Office Websites (Extended Search)

Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Time-of-flight mass spectrometer comprising a first drift region and a second drift region enclosed within an evacuation chamber. Available for thumbnail of Feynman Center (505) 665-9090 Email Linear Electric Field Time-Of-Flight Ion Mass Spectrometers Time-of-flight mass spectrometer comprising a first drift region and a second drift region enclosed within an evacuation chamber; a means of introducing an analyte of interest into the first drift region; a pulsed ionization source which produces molecular ions from said analyte of interest; a first foil positioned between the first drift region and the second drift region, which dissociates said molecular ions into constituent

274

Mass dependency of turbulent parameters in stationary glow discharge plasmas  

SciTech Connect

A direct current glow discharge tube is used to determine how mass changes the effects of certain turbulence characteristics in a weakly ionized gas. Helium, neon, argon, and krypton plasmas were created, and an axial magnetic field, varied from 0.0 to 550.0 Gauss, was used to enhance mass dependent properties of turbulence. From the power spectra of light emission variations associated with velocity fluctuations, determination of mass dependency on turbulent characteristic unstable modes, energy associated with turbulence, and the rate at which energy is transferred from scale to scale are measured. The magnetic field strength is found to be too weak to overcome particle diffusion to the walls to affect the turbulence in all four types of plasmas, though mass dependency is still detected. Though the total energy and the rate at which the energy moves between scales are mass invariant, the amplitude of the instability modes that characterize each plasma are dependent on mass.

Titus, J. B.; Alexander, A. B. [Florida A and M University, Tallahassee, Florida 32310 (United States)] [Florida A and M University, Tallahassee, Florida 32310 (United States); Wiggins, D. L. [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53703 (United States)] [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53703 (United States); Johnson, J. A. III [Pyramid Plasmas LLC, Lawrenceville, Georgia 30043 (United States)] [Pyramid Plasmas LLC, Lawrenceville, Georgia 30043 (United States)

2013-05-15T23:59:59.000Z

275

Line-driven winds, ionizing fluxes and UV-spectra of hot stars at extremely low metallicity. I. Very massive O-stars  

E-Print Network (OSTI)

Wind models of very massive stars with metallicities in a range from 1E-4 to 1.0 solar are calculated using a new treatment of radiation driven winds with depth dependent radiative force multipliers and a comprehensive list of more than two million spectral lines in NLTE. The models are tested by a comparison with observed stellar wind properties of O stars in the Galaxy and the SMC. Satisfying agreement is found. The calculations yield mass-loss rates, wind velocities, wind momenta and wind energies as a function of metallicity and can be used to discuss the influence of stellar winds on the evolution of very massive stars in the early universe and on the interstellar medium in the early phases of galaxy formation. The normal scaling laws, which predict stellar mass-loss rates and wind momenta to decrease as a power law with metal abundance break down at a certain threshold. Analytical fit formulae for mass-loss rates are provided as a function of stellar parameters and metallicity. The new wind models are applied to calculate ionizing fluxes and observable spectra of very massive stars as a function of metallicity using the new hydrodynamic, non-LTE line-blanketed flux constant model atmosphere code developed by Pauldrach et al. Numbers of ionizing photons for the crucial ionization stages are given. For a fixed effective temperature the He II ionizing emergent flux depends very strongly on metallicity but also on stellar luminosity. A strong dependence on metallicity is also found for the C III, Ne II and O II ionizing photons, whereas the H I and He I ionizing flux is almost independent of metallicity. We also calculate UV spectra for all the models and discuss the behaviour of significant line features as a function of metallicity.

Rolf P. Kudritzki

2002-05-14T23:59:59.000Z

276

HEATS: Thermal Energy Storage  

SciTech Connect

HEATS Project: The 15 projects that make up ARPA-E’s HEATS program, short for “High Energy Advanced Thermal Storage,” seek to develop revolutionary, cost-effective ways to store thermal energy. HEATS focuses on 3 specific areas: 1) developing high-temperature solar thermal energy storage capable of cost-effectively delivering electricity around the clock and thermal energy storage for nuclear power plants capable of cost-effectively meeting peak demand, 2) creating synthetic fuel efficiently from sunlight by converting sunlight into heat, and 3) using thermal energy storage to improve the driving range of electric vehicles (EVs) and also enable thermal management of internal combustion engine vehicles.

None

2012-01-01T23:59:59.000Z

277

Holographic thermalization patterns  

E-Print Network (OSTI)

We investigate the behaviour of various correlators in N=4 super Yang Mills theory, taking finite coupling corrections into account. In the thermal limit we investigate the flow of the quasinormal modes as a function of the 't Hooft coupling. Then by using a specific model of holographic thermalization we investigate the deviation of the spectral densities from their thermal limit in an out-of-equilibrium situation. The main focus lies on the thermalization pattern with which the various plasma constituents of different energies approach their final thermal distribution as the coupling constant decreases from the infinite coupling limit. All results point towards the weakening of the usual top down thermalization pattern.

Stefan Stricker

2014-03-11T23:59:59.000Z

278

Holographic thermalization patterns  

E-Print Network (OSTI)

We investigate the behaviour of various correlators in N=4 super Yang Mills theory, taking finite coupling corrections into account. In the thermal limit we investigate the flow of the quasinormal modes as a function of the 't Hooft coupling. Then by using a specific model of holographic thermalization we investigate the deviation of the spectral densities from their thermal limit in an out-of-equilibrium situation. The main focus lies on the thermalization pattern with which the various plasma constituents of different energies approach their final thermal distribution as the coupling constant decreases from the infinite coupling limit. All results point towards the weakening of the usual top down thermalization pattern.

Stricker, Stefan

2014-01-01T23:59:59.000Z

279

Lattice Boltzmann method for weakly ionized isothermal plasmas  

Science Journals Connector (OSTI)

In this paper, a lattice Boltzmann method (LBM) for weakly ionized isothermal plasmas is presented by introducing a rescaling scheme for the Boltzmann transport equation. Without using this rescaling, we found that the nondimensional relaxation time used in the LBM is too large and the LBM does not produce physically realistic results. The developed model was applied to the electrostatic wave problem and the diffusion process of singly ionized helium plasmas with a 1–3% degree of ionization under an electric field. The obtained results agree well with theoretical values.

Huayu Li and Hyungson Ki

2007-12-21T23:59:59.000Z

280

Lattice Boltzmann method for weakly ionized isothermal plasmas  

SciTech Connect

In this paper, a lattice Boltzmann method (LBM) for weakly ionized isothermal plasmas is presented by introducing a rescaling scheme for the Boltzmann transport equation. Without using this rescaling, we found that the nondimensional relaxation time used in the LBM is too large and the LBM does not produce physically realistic results. The developed model was applied to the electrostatic wave problem and the diffusion process of singly ionized helium plasmas with a 1-3% degree of ionization under an electric field. The obtained results agree well with theoretical values.

Li Huayu; Ki, Hyungson [Department of Mechanical Engineering, Michigan State University, East Lansing, Michigan 48824-1226 (United States)

2007-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Photo-double-ionization of the nitrogen molecule  

Science Journals Connector (OSTI)

The triple differential cross sections of the photo-double-ionization of the nitrogen molecule to the X 1?+g and a3?u N22+ states have been measured at about 20 eV above their respective ionization thresholds in the equal energy sharing kinematics and calculated using a model which makes use of correlated two-center double continuum wave functions. The comparison of the results with those obtained by the Gaussian parametrization method applied in the past with success to heliumlike targets shows the influence of the molecular nature of the N2 target in the photo-double-ionization.

P. Bolognesi; B. Joulakian; A. A. Bulychev; O. Chuluunbaatar; L. Avaldi

2014-05-07T23:59:59.000Z

282

The Density Effect for the Ionization Loss in Various Materials  

Science Journals Connector (OSTI)

The density effect for the ionization loss of charged particles has been calculated for a number of metals, scintillating materials, gases at various pressures, and photographic emulsion, using a dispersion model involving an appropriate number of dispersion oscillators for each substance. The results are presented in the form of graphs which can be used to correct the ionization loss for the density effect. The theoretical curves for silver chloride and anthracene are in reasonable agreement with experiments on the ionization loss of ?-mesons. A general derivation of the equations for the density effect is given.

R. M. Sternheimer

1952-11-15T23:59:59.000Z

283

Ionization and scintillation of nuclear recoils in gaseous xenon  

E-Print Network (OSTI)

Ionization and scintillation produced by nuclear recoils in gaseous xenon at approximately 14 bar have been simultaneously observed in an electroluminescent time projection chamber. Neutrons from radioisotope $\\alpha$-Be neutron sources were used to induce xenon nuclear recoils, and the observed recoil spectra were compared to a detailed Monte Carlo employing estimated ionization and scintillation yields for nuclear recoils. The ability to discriminate between electronic and nuclear recoils using the ratio of ionization to primary scintillation is demonstrated. These results encourage further investigation on the use of xenon in the gas phase as a detector medium in dark matter direct detection experiments.

J. Renner; V. M. Gehman; A. Goldschmidt; H. S. Matis; T. Miller; Y. Nakajima; D. Nygren; C. A. B. Oliveira; D. Shuman; V. Álvarez; F. I. G. Borges; S. Cárcel; J. Castel; S. Cebrián; A. Cervera; C. A. N. Conde; T. Dafni; T. H. V. T. Dias; J. Díaz; R. Esteve; P. Evtoukhovitch; L. M. P. Fernandes; P. Ferrario; A. L. Ferreira; E. D. C. Freitas; A. Gil; H. Gómez; J. J. Gómez-Cadenas; D. González-Díaz; R. M. Gutiérrez; J. Hauptman; J. A. Hernando Morata; D. C. Herrera; F. J. Iguaz; I. G. Irastorza; M. A. Jinete; L. Labarga; A. Laing; I. Liubarsky; J. A. M. Lopes; D. Lorca; M. Losada; G. Luzón; A. Marí; J. Martín-Albo; A. Martínez; A. Moiseenko; F. Monrabal; M. Monserrate; C. M. B. Monteiro; F. J. Mora; L. M. Moutinho; J. Muñoz Vidal; H. Natal da Luz; G. Navarro; M. Nebot-Guinot; R. Palma; J. Pérez; J. L. Pérez Aparicio; L. Ripoll; A. Rodríguez; J. Rodríguez; F. P. Santos; J. M. F. dos Santos; L. Seguí; L. Serra; A. Simón; C. Sofka; M. Sorel; J. F. Toledo; A. Tomás; J. Torrent; Z. Tsamalaidze; J. F. C. A. Veloso; J. A. Villar; R. C. Webb; J. White; N. Yahlali

2014-09-09T23:59:59.000Z

284

A study of electron recombination using highly ionizing particles...  

NLE Websites -- All DOE Office Websites (Extended Search)

mobility * Electron MFP 20 nm * Onsager radius 130 nm (E Coulomb E thermal ) * No vibration levels available 1 nsec thermalization time * Electrons in Coulomb field or...

285

Systems and methods for cylindrical hall thrusters with independently controllable ionization and acceleration stages  

DOE Patents (OSTI)

Systems and methods may be provided for cylindrical Hall thrusters with independently controllable ionization and acceleration stages. The systems and methods may include a cylindrical channel having a center axial direction, a gas inlet for directing ionizable gas to an ionization section of the cylindrical channel, an ionization device that ionizes at least a portion of the ionizable gas within the ionization section to generate ionized gas, and an acceleration device distinct from the ionization device. The acceleration device may provide an axial electric field for an acceleration section of the cylindrical channel to accelerate the ionized gas through the acceleration section, where the axial electric field has an axial direction in relation to the center axial direction. The ionization section and the acceleration section of the cylindrical channel may be substantially non-overlapping.

Diamant, Kevin David; Raitses, Yevgeny; Fisch, Nathaniel Joseph

2014-05-13T23:59:59.000Z

286

Non-thermal Plasma Chemistry Non-thermal Thermal  

E-Print Network (OSTI)

automotive industry optics biomedical technology environmental technology Plasma Technology Quote from: Pla-thermal Plasma Chemical Flow Reactor #12;Werner von Siemens ,, ... construction of an apparatus generation (1857) pollution control volatile organic components, NOx reforming, ... radiation sources excimer

Greifswald, Ernst-Moritz-Arndt-Universität

287

Thermal contact resistance  

E-Print Network (OSTI)

This work deals with phenomena of thermal resistance for metallic surfaces in contact. The main concern of the work is to develop reliable and practical methods for prediction of the thermal contact resistance for various ...

Mikic, B. B.

1966-01-01T23:59:59.000Z

288

Solar Thermal Processes  

Science Journals Connector (OSTI)

The use of solar energy for desalination purposes was one of ... The process is based on the use of solar thermal energy to evaporate water, thus separating pure ... brine. In this chapter an overview of solar thermal

M.T. Chaibi; Ali M. El-Nashar

2009-01-01T23:59:59.000Z

289

Thermal Neutron Scattering  

Science Journals Connector (OSTI)

... of its title. It is not for the nuclear physicist, nor even for the neutron physicist, but for the student of solids and liquids. "Thermal ... physicist, but for the student of solids and liquids. "Thermal neutron ...

G. E. BACON

1968-11-09T23:59:59.000Z

290

Rules and Regulations for Control of Ionizing Radiation (Arkansas) |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Rules and Regulations for Control of Ionizing Radiation (Arkansas) Rules and Regulations for Control of Ionizing Radiation (Arkansas) Rules and Regulations for Control of Ionizing Radiation (Arkansas) < Back Eligibility Utility Program Info State Arkansas Program Type Environmental Regulations Siting and Permitting Provider Department of Health The Rules and Regulations for Control of Ionizing Radiation are the Arkansas state laws made in accordance the federal Nuclear Regulatory Commission Rules. Any contractor with the US DOE or US Nuclear Regulatory Commission is exempt from the state laws. This set of rules and regulations basically restates the federal policy to ensure that Arkansas is in compliance with the federal standards governing nuclear energy. Specifically the State rules are equivalent to Nuclear Regulatory

291

The Degradation of Solid Polymethylmethacrylate by Ionizing Radiation  

Science Journals Connector (OSTI)

...Polymethylmethacrylate by Ionizing Radiation P. Alexander A. Charlesby...inversely proportional to the radiation dose (plus a small quantity of...of measuring high-energy radiation doses in the range of about 1 million rontgens...

1954-01-01T23:59:59.000Z

292

Ionizing Radiation Induces Delayed Hyperrecombination in Mammalian Cells  

Science Journals Connector (OSTI)

...instability is critical to radiation risk assessment and for determining...the many delayed effects of radiation, chromosomal instability is...detrimental effects over a range of doses of ionizing radiation. Furthermore, a rapid and...

Lei Huang; Suzanne Grim; Leslie E. Smith; Perry M. Kim; Jac A. Nickoloff; Olga G. Goloubeva; William F. Morgan

2004-06-01T23:59:59.000Z

293

22.01 Introduction to Ionizing Radiation, Fall 2003  

E-Print Network (OSTI)

Introduction to basic properties of ionizing radiations and their uses in medicine, industry, science, and environmental studies. Discusses natural and man-made radiation sources, energy deposition and dose calculations, ...

Coderre, Jeffrey A.

294

Laser Multiphoton Ionization of Tetrakis(dimethylamino)ethylene  

Science Journals Connector (OSTI)

(4) Also, TDAE has found a place in current plasma research as it can produce plasmas at densities approaching 1013 charges per cm3 via ionization with 193 nm light. ...

Byron H. Smith; Robert N. Compton

2014-02-22T23:59:59.000Z

295

Underground Coal Thermal Treatment  

SciTech Connect

The long-term objective of this work is to develop a transformational energy production technology by insitu thermal treatment of a coal seam for the production of substitute natural gas (SNG) while leaving much of the coalâ??s carbon in the ground. This process converts coal to a high-efficiency, low-GHG emitting gas fuel. It holds the potential of providing environmentally acceptable access to previously unusable coal resources. This topical report discusses the development of experimental capabilities, the collection of available data, and the development of simulation tools to obtain process thermo-chemical and geo-thermal parameters in preparation for the eventual demonstration in a coal seam. It also includes experimental and modeling studies of CO{sub 2} sequestration. Efforts focused on: â?¢ Constructing a suite of three different coal pyrolysis reactors. These reactors offer the ability to gather heat transfer, mass transfer and kinetic data during coal pyrolysis under conditions that mimic in situ conditions (Subtask 6.1). â?¢ Studying the operational parameters for various underground thermal treatment processes for oil shale and coal and completing a design matrix analysis for the underground coal thermal treatment (UCTT). This analysis yielded recommendations for terms of targeted coal rank, well orientation, rubblization, presence of oxygen, temperature, pressure, and heating sources (Subtask 6.2). â?¢ Developing capabilities for simulating UCTT, including modifying the geometry as well as the solution algorithm to achieve long simulation times in a rubblized coal bed by resolving the convective channels occurring in the representative domain (Subtask 6.3). â?¢ Studying the reactive behavior of carbon dioxide (CO{sub 2}) with limestone, sandstone, arkose (a more complex sandstone) and peridotite, including mineralogical changes and brine chemistry for the different initial rock compositions (Subtask 6.4). Arkose exhibited the highest tendency of participating in mineral reactions, which can be attributed to the geochemical complexity of its initial mineral assemblage. In experiments with limestone, continuous dissolution was observed with the release of CO{sub 2} gas, indicated by the increasing pressure in the reactor (formation of a gas chamber). This occurred due to the lack of any source of alkali to buffer the solution. Arkose has the geochemical complexity for permanent sequestration of CO{sub 2} as carbonates and is also relatively abundant. The effect of including NH{sub 3} in the injected gas stream was also investigated in this study. Precipitation of calcite and trace amounts of ammonium zeolites was observed. A batch geochemical model was developed using Geochemists Workbench (GWB). Degassing effect in the experiments was corrected using the sliding fugacity model in GWB. Experimental and simulation results were compared and a reasonable agreement between the two was observed.

P. Smith; M. Deo; E. Eddings; A. Sarofim; K. Gueishen; M. Hradisky; K. Kelly; P. Mandalaparty; H. Zhang

2011-10-30T23:59:59.000Z

296

Thermal neutron detection system  

DOE Patents (OSTI)

According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.

Peurrung, Anthony J. (Richland, WA); Stromswold, David C. (West Richland, WA)

2000-01-01T23:59:59.000Z

297

Thermal Performance Benchmarking (Presentation)  

SciTech Connect

This project will benchmark the thermal characteristics of automotive power electronics and electric motor thermal management systems. Recent vehicle systems will be benchmarked to establish baseline metrics, evaluate advantages and disadvantages of different thermal management systems, and identify areas of improvement to advance the state-of-the-art.

Moreno, G.

2014-11-01T23:59:59.000Z

298

Multiwavelength Thermal Emission  

E-Print Network (OSTI)

Multiwavelength Astronomy NASA #12;Thermal Emission #12;Thermal Emission Non-thermal p-p collisions Optical IR Radio/ Microwave sources of emission massive stars, WHIM, Ly many dust, cool objects-ray ~GeV Gamma-ray ~TeV sources of emission AGN, clusters, SNR, binaries, stars AGN (obscured), shocks

California at Santa Cruz, University of

299

U.S. Department of Energy Categorical Exclusion ...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Mass Spectrometry in 735-A Savannah River Site AikenAikenSouth Carolina Nonproliferation Technology Section (NTS) personnel operate a thermal ionization mass spectrometry (TIMS)...

300

Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation  

NLE Websites -- All DOE Office Websites (Extended Search)

Site-Selective Ionization in Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Wednesday, 30 June 2010 00:00 Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters composed of argon (Ar) shells and xenon (Xe) cores. The clusters were site-selectively ionized (i.e, ionization took place either in the xenon core or in the argon shell). Using a high-resolution photoelectron-ion coincidence technique at ALS Beamlines 10.0.1 and 11.0.2, the researchers concluded that charge-transfer processes and fragmentation dynamics are strongly influenced by the environment of the initially ionized atoms.

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301

ALFVEN WAVES IN A PARTIALLY IONIZED TWO-FLUID PLASMA  

SciTech Connect

Alfven waves are a particular class of magnetohydrodynamic waves relevant in many astrophysical and laboratory plasmas. In partially ionized plasmas the dynamics of Alfven waves is affected by the interaction between ionized and neutral species. Here we study Alfven waves in a partially ionized plasma from the theoretical point of view using the two-fluid description. We consider that the plasma is composed of an ion-electron fluid and a neutral fluid, which interact by means of particle collisions. To keep our investigation as general as possible, we take the neutral-ion collision frequency and the ionization degree as free parameters. First, we perform a normal mode analysis. We find the modification due to neutral-ion collisions of the wave frequencies and study the temporal and spatial attenuation of the waves. In addition, we discuss the presence of cutoff values of the wavelength that constrain the existence of oscillatory standing waves in weakly ionized plasmas. Later, we go beyond the normal mode approach and solve the initial-value problem in order to study the time-dependent evolution of the wave perturbations in the two fluids. An application to Alfven waves in the low solar atmospheric plasma is performed and the implication of partial ionization for the energy flux is discussed.

Soler, R.; Ballester, J. L.; Terradas, J. [Departament de Fisica, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Carbonell, M., E-mail: roberto.soler@uib.es, E-mail: joseluis.ballester@uib.es, E-mail: jaume.terradas@uib.es, E-mail: marc.carbonell@uib.es [Departament de Matematiques i Informatica, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain)

2013-04-20T23:59:59.000Z

302

Ionization and maximum energy of nuclei in shock acceleration theory  

E-Print Network (OSTI)

We study the acceleration of heavy nuclei at SNR shocks when the process of ionization is taken into account. Heavy atoms ($Z_N >$ few) in the interstellar medium which start the diffusive shock acceleration (DSA) are never fully ionized at the moment of injection. The ionization occurs during the acceleration process, when atoms already move relativistically. For typical environment around SNRs the photo-ionization due to the background galactic radiation dominates over Coulomb collisions. The main consequence of ionization is the reduction of the maximum energy which ions can achieve with respect to the standard result of the DSA. In fact the photo-ionization has a timescale comparable to the beginning of the Sedov-Taylor phase, hence the maximum energy is no more proportional to the nuclear charge, as predicted by standard DSA, but rather to the effective ions' charge during the acceleration process, which is smaller than the total nuclear charge $Z_N$. This result can have a direct consequence in the pred...

Morlino, Giovanni

2011-01-01T23:59:59.000Z

303

The stability of weakly ionized collisional dusty plasma in the presence of flow  

SciTech Connect

The stability of weakly ionized and magnetized plasma in the presence of transverse (to the magnetic field) neutral wind is investigated in the present work. The collisional coupling of ambient background flow to the magnetized plasma gives rise to an electric field. In the presence of charged unmagnetized dust, electrostatic fluctuations in such plasma become unstable, with the growth rate dependent on the plasma thermal speed as well as on the dust charge and collision frequencies. This instability is similar to the Farley-Buneman instability. However, unlike Farley-Buneman, where the growth rate is directly dependent on the background flow, this dependence in the present case is only indirect. It is shown that this instability can grow over few seconds in the Earth's lower ionosphere and thus could play an important role in the structure formation.

Pandey, B. P. [Department of Physics, Astronomy and Research Centre for Astronomy, Astrophysics and Astrophotonics, Macquarie University, Sydney, NSW 2109 (Australia); Vranjes, J. [Von Karman Institute, Waterloosesteenweg 72, 1640 Sint-Genesius-Rode, Brussels (Belgium); Vladimirov, S. V. [School of Physics, University of Sydney, NSW 2006 (Australia); Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation)

2012-09-15T23:59:59.000Z

304

Focused analyte spray emission apparatus and process for mass spectrometric analysis  

DOE Patents (OSTI)

An apparatus and process are disclosed that deliver an analyte deposited on a substrate to a mass spectrometer that provides for trace analysis of complex organic analytes. Analytes are probed using a small droplet of solvent that is formed at the junction between two capillaries. A supply capillary maintains the droplet of solvent on the substrate; a collection capillary collects analyte desorbed from the surface and emits analyte ions as a focused spray to the inlet of a mass spectrometer for analysis. The invention enables efficient separation of desorption and ionization events, providing enhanced control over transport and ionization of the analyte.

Roach, Patrick J. (Kennewick, WA); Laskin, Julia (Richland, WA); Laskin, Alexander (Richland, WA)

2012-01-17T23:59:59.000Z

305

Serum Diagnosis of Pancreatic Adenocarcinoma Using Surface-Enhanced Laser Desorption and Ionization Mass Spectrometry  

Science Journals Connector (OSTI)

...usable for biomarker discovery has been essential to...Sinapinic acid solution as energy absorbing matrix was...room temperature in the dark until further use. All...variability, especially of the energy-absorbing matrix. The findings reported in our discovery-phase study need to...

Jens Koopmann; Zhen Zhang; Nicole White; Jason Rosenzweig; Neal Fedarko; Sanjay Jagannath; Marcia I. Canto; Charles J. Yeo; Daniel W. Chan; and Michael Goggins

2004-02-01T23:59:59.000Z

306

From chlorinated transformation products to highly hydrated ions with electrospray ionization mass spectrometry.  

E-Print Network (OSTI)

??Pharmaceutical and personal care products (PPCPs) triclosan and nonylphenol, were investigated throughout wastewater treatment in a publicly owned treatment works (POTW). Both compounds react quickly… (more)

Pape, Jennifer Lynn

2011-01-01T23:59:59.000Z

307

High-Resolution Desorption Electrospray Ionization Mass Spectrometry for Chemical Characterization  

E-Print Network (OSTI)

, University of California-Irvine, Irvine, California 92697 Characterization of the chemical composition solar radiation and modifications of cloud properties.1-6 The extent of radiative forcing and cloud

Nizkorodov, Sergey

308

PCRElectrospray Ionization Mass Spectrometry The Potential to Change Infectious Disease Diagnostics in  

E-Print Network (OSTI)

funding and educational honoraria from Abbott Molecular and Ibis Biosciences (D.M.W.). Accepted for publication February 9, 2012. Disclosure: D.M.W. receives research grants, consulting fees, and

Wysocki, Vicki H.

309

Observation of duplex DNA-drug noncovalent complexes by electrospray ionization mass spectrometry  

SciTech Connect

We have observed by ESI-MS the noncovalent complex formed between a minor groove binding molecule and a 12 base pair self-complementary oligonucleotide. When the ratio of Distamycin Dm to oligonucleotide was varied, oligonucleotide duplex, 1:1 Dm/oligonucleotide duplex, and 2:1 Dm/oligonucleotide duplex noncovalent complexes were observed, consistent with NMR results for the same sequence and Dm to oligonucleotide duplex concentration ratios. These results indicate that ESI-MS is an effective analytical technique for the detection of specific drug-oligonucleotide duplex noncovalent complexes and that specific noncovalent complexes can be observed reflecting stoichiometry in solution. Additional experiments to determine if ESI-MS can provide information on the specificity and selectivity of additional minor groove binding and intercalating molecules are in progress. 19 refs., 1 fig.

Gale, D.C.; Goodlett, D.R.; Light-Wahl, K.J.; Smith, R.D. (Pacific Northwest Lab., Richland, WA (United States))

1994-06-29T23:59:59.000Z

310

Developments and Applications of Electrophoresis and Small Molecule Laser Desorption Ionization Mass Spectrometry  

SciTech Connect

Ultra-sensitive native fluorescence detection of proteins with miniaturized one- and two-dimensional polyacrylamide gel electrophoresis was achieved with laser side-entry excitation, which provides both high excitation power and low background level. The detection limit for R-phycoerythrin protein spots in 1-D SDS-PAGE was as low as 15 fg, which corresponds to 40 thousand molecules only. The average detection limit of six standard native proteins was 5 pg per band and the dynamic range spanned more than 3 orders of magnitude. Approximately 150 protein spots from 30 ng of total Escherichia coli extraction were detected on a 0.8 cm x 1 cm gel in two-dimensional separation. Estrogen-DNA adducts as 4-OHE{sub 1}(E{sub 2})-1-N3Ade and 4-OHEI(E2)-2-NacCys were hypothesized as early risk assessment of prostate and breast cancers. Capillary electrophoresis, luminescence/absorption spectroscopy and LC-MS were used to characterize and detect these adducts. Monoclonal antibodies against each individual adduct were developed and used to enrich such compounds from urine samples of prostate and breast cancer patients as well as healthy people. Adduct 4-OHE{sub 1}-1-N3Ade was detected at much higher level in urine from subjects with prostate cancer patients compared to healthy males. The same adduct and 4-OHEI-2-NacCys were also detected at a much higher level in urine from a woman with breast carcinoma than samples from healthy controls. These two DNA adducts may serve as novel biomarkers for early diagnostic of cancers. The adsorption properties of R-phycoerythrin (RPE), on the fused-silica surface were studied using capillary electrophoresis (CE) and single molecule spectroscopy. The band shapes and migration times were measured in CE. Adsorption and desorption events were recorded at the single-molecule level by imaging of the evanescent-field layer using total internal reflection. The adsorbed RPE molecules on the fused-silica prism surface were counted with confidence based on Imagej software. The capacity factor and desorption rate were estimated from the counting results. The mobility-based adsorption isotherms were constructed from both computer simulations and experiments to determine the capacity factor.

Hui Zhang

2007-12-01T23:59:59.000Z

311

Two decades of studying non-covalent biomolecular assemblies by means of electrospray ionization mass spectrometry  

Science Journals Connector (OSTI)

...charge suggests a folded protein state whereas an unfolded/disordered protein will have an extended...of the heterogeneous ensemble populated by alphaB-crystallin...Detection of multiple protein conformational ensembles in solution via deconvolution...

2012-01-01T23:59:59.000Z

312

In Situ Metabolic Profiling of Single Cells by Laser Ablation Electrospray Ionization Mass Spectrometry  

Science Journals Connector (OSTI)

Further removal of the fiber tip from the cell surface resulted in no ablation, whereas closer approach often led to damage to the cell or the fiber tip. ... Ten organic purple A. cepa bulbs (5?7 cm transverse diameter) were purchased from a local store (distributed by CFF Fresh, Sedro-Woolley, WA and bought in Washington, DC), and four N. pseudonarcissus bulb were obtained from Reston, VA. ... For sodium and potassium, or any other ionic species, charge displacement of a fluorescent cation results in indirect fluorescence detection. ...

Bindesh Shrestha; Akos Vertes

2009-09-17T23:59:59.000Z

313

Factors Affecting Quantitative Analysis in Laser Desorption/Laser Ionization Mass Spectrometry  

E-Print Network (OSTI)

of trace organic compounds, particularly polycyclic aromatic hydrocarbons (PAHs). Recent efforts have of complex mixtures. µL2MS has been most widely used to detect polycyclic aromatic hydrocarbons (PAHs and soils,2,3 meteorites,4,5 atmospheric aerosols,6 agricultural samples,7,8 polymers,9 and natural water

Zare, Richard N.

314

Explorations of Functionalized Gold Nanoparticle Surface Chemistry for Laser Desorption Ionization Mass Spectrometry Applications  

E-Print Network (OSTI)

the azo SAM molecules on 2, 5, 20, 30, and 50 nm AuNPs exploring the changes of Relative Ion Yield (RIY) with increased AuNP diameters. Our results indicate that the role of the SAM to drive energy deposition decreases as the size of the AuNP increases...

Gomez Hernandez, Mario 1980-

2012-07-11T23:59:59.000Z

315

Ionization of dimethyluracil dimers leads to facile proton transfer in the absence of H-bonds  

E-Print Network (OSTI)

and electronic structure calculations. Ionization initiates3 commercially. Electronic structure calculations were

Golan, Amir

2012-01-01T23:59:59.000Z

316

The similar effects of low-dose ionizing radiation and non-ionizing radiation from background environmental levels of exposure  

Science Journals Connector (OSTI)

The meltdown and release of radioactivity (ionizing radiation) from four damaged nuclear reactors at the Fukushima Nuclear Facility in Japan in March 2011 continues to contaminate air and ocean water even 1 year ...

Cindy Sage

2012-06-01T23:59:59.000Z

317

Solar wind electron temperature and density measurements on the Solar Orbiter with thermal noise spectroscopy  

E-Print Network (OSTI)

Solar wind electron temperature and density measurements on the Solar Orbiter with thermal noise of the plasma thermal noise analysis for the Solar Orbiter, in order to get accurate measurements of the total of their small mass and therefore large thermal speed, the solar wind electrons are expected to play a major role

California at Berkeley, University of

318

Cross-plane thermal properties of transition metal dichalcogenides  

SciTech Connect

In this work, we explore the thermal properties of hexagonal transition metal dichalcogenide compounds with different average atomic masses but equivalent microstructures. Thermal conductivity values of sputtered thin films were compared to bulk crystals. The comparison revealed a >10 fold reduction in thin film thermal conductivity. Structural analysis of the films revealed a turbostratic structure with domain sizes on the order of 5-10 nm. Estimates of phonon scattering lengths at domain boundaries based on computationally derived group velocities were consistent with the observed film microstructure, and accounted for the reduction in thermal conductivity compared to values for bulk crystals.

Muratore, C. [Department of Chemical and Materials Engineering, University of Dayton, Dayton, Ohio 45469 (United States) [Department of Chemical and Materials Engineering, University of Dayton, Dayton, Ohio 45469 (United States); Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States); Varshney, V. [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States) [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States); Universal Technology Corporation, Dayton, Ohio 45432 (United States); Gengler, J. J. [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States) [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States); Spectral Energies LLC, Dayton, Ohio 45431 (United States); Hu, J. J.; Bultman, J. E. [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States) [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States); University of Dayton Research Institute, Dayton, Ohio 45469 (United States); Smith, T. M. [Department of Materials Science and Engineering, Ohio State University, Columbus, Ohio 43210 (United States)] [Department of Materials Science and Engineering, Ohio State University, Columbus, Ohio 43210 (United States); Shamberger, P. J.; Roy, A. K.; Voevodin, A. A. [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States)] [Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 (United States); Qiu, B.; Ruan, X. [Department of Mechanical Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States)] [Department of Mechanical Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States)

2013-02-25T23:59:59.000Z

319

Thermal Insulation in Solar Thermal Devices  

Science Journals Connector (OSTI)

Thermal Insulation is a device or a practice which is used in a system for minimising heat losses caused due to transfer of heat from hotter to colder regions. It is one of the cheapest methods of energy conse...

B. C. Raychaudhuri

1986-01-01T23:59:59.000Z

320

Improving liquid chromatography-mass spectrometry sensitivity...  

NLE Websites -- All DOE Office Websites (Extended Search)

sensitivity using a subambient pressure ionization with nanoelectrospray (SPIN Abstract: In this work the Subambient Pressure Ionization with Nanoelectrospray (SPIN) ion...

Note: This page contains sample records for the topic "thermal ionization mass" 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

Thermal metastabilities in the solar core  

E-Print Network (OSTI)

Linear stability analysis indicates that solar core is thermally stable for infinitesimal internal perturbations. For the first time, thermal metastabilities are found in the solar core when outer perturbations with significant amplitude are present. The obtained results show that hot bubbles generated by outer perturbations may travel a significant distance in the body of the Sun. These deep-origin hot bubbles have mass, energy, and chemical composition that may be related to solar flares. The results obtained may have remarkable relations to activity cycles in planets like Jupiter and also in extrasolar planetary systems.

Attila Grandpierre; Gabor Agoston

2002-01-18T23:59:59.000Z

322

The chemistry of high-mass star formation  

E-Print Network (OSTI)

This paper reviews the chemistry of star-forming regions, with an emphasis on the formation of high-mass stars. We first outline the basic molecular processes in dense clouds, their implementation in chemical models, and techniques to measure molecular abundances. Then, recent observational, theoretical and laboratory developments are reviewed on the subjects of hot molecular cores, cosmic-ray ionization, depletion and deuteration, and oxygen chemistry. The paper concludes with a summary of outstanding problems and future opportunities.

Floris F. S. van der Tak

2005-06-07T23:59:59.000Z

323

Plasmadynamics and ionization kinetics of thermionic energy conversion  

SciTech Connect

To reduce the plasma arc-drop, thermionic energy conversion is studied with both analytical and numerical tools. Simplifications are made in both the plasmadynamic and ionization-recombination theories. These are applied to a scheme proposed presently using laser irradiation to enhance the ionization kinetics of the thermionic plasma and thereby reduce the arc-drop. It is also predicted that it is possible to generate the required laser light from a thermionic-type Cesium plasma. The analysis takes advantage of theoretical simplifications derived for the ionization-recombination kinetics. It is shown that large laser ionization enhancements can occur and that collisional Cesium recombination lasing is expected. To complement the kinetic theory, a numerical method is developed to solve the thermionic plasma dynamics. The effects of the complete system of electron-atom inelastic collisions on the ionization-recombination problem are shown to reduce to a system nearly as simple as the well-known one-quantum approximation. To combine the above analysis of ionization-recombination kinetics with the plasma dynamics of thermionic conversion, a finite difference computer program is constructed. Using the above developments, a proposal to improve thermionic converter performance using laser radiation is considered. In this proposed scheme, laser radiation impinging on a thermionic plasma enhances the ionization process thereby raising the plasma density and reducing the plasma arc-drop. A source for such radiation may possibly be a Cesium recombination laser operating in a different thermionic converter. The possibility of this being an energy efficient process is discussed.

Lawless, J.L. Jr.

1981-01-01T23:59:59.000Z

324

STATUS OF THE MILANO NEUTRINO MASS EXPERIMENT WITH THERMAL DETECTORS  

E-Print Network (OSTI)

Science, University of California, Berkeley CA 94720, USA In this paper we present our recent developments eV. The recent hints on atmospheric, solar and reactor neutrino oscillations 1 increase the interest=C and therefore any material with a low heat capacity C

325

The design and analysis of a thermal mass groundwater flowmeter  

E-Print Network (OSTI)

Bz (4 s) conductive flux at r + Ar: q, (, +o?s 2z(r + ftr)Az (45) conductive flux at z: q ~ s 2zrAr (4c) conduciive flux st z+ diz: q ~ qn s 2rrrkr (4d) advective flux at z: pcu(Tf ? Ts)~ s 2rrrkr (4c) advective flux at z+ 4z: pcu(TI ? Ts)~ +sr.... 00915 to 5. 66 ml/min. This represents average velocities in the tube of 4. 31 x 10 4 cm/s to 0. 101 cm/s. The syringe pump is calibrated for each flowrate prior to flowmeter calibration using a stopwatch and graduated cylinder. Each tube...

Weathers, Lenly Joseph

2012-06-07T23:59:59.000Z

326

A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source  

E-Print Network (OSTI)

Most ultraluminous X-ray sources (ULXs) display a typical set of properties not seen in Galactic stellar-mass black holes (BHs): higher luminosity Lx > 3 10^39 erg/s, unusually soft X-ray components (kT solar masses. Our results demonstrate that in P13, soft thermal emission and spectral curvature are indeed signatures of supercritical accretion. ...

Motch, C; Soria, R; Grisé, F; Pietrzy?ski, G

2014-01-01T23:59:59.000Z

327

Beam Head Erosion in Self-Ionized Plasma Wakefield Accelerators  

SciTech Connect

In the recent plasma wakefield accelerator experiments at SLAC, the energy of the particles in the tail of the 42 GeV electron beam were doubled in less than one meter [1]. Simulations suggest that the acceleration length was limited by a new phenomenon--beam head erosion in self-ionized plasmas. In vacuum, a particle beam expands transversely in a distance given by {beta}*. In the blowout regime of a plasma wakefield [2], the majority of the beam is focused by the ion channel, while the beam head slowly spreads since it takes a finite time for the ion channel to form. It is observed that in self-ionized plasmas, the head spreading is exacerbated compared to that in pre-ionized plasmas, causing the ionization front to move backward (erode). A simple theoretical model is used to estimate the upper limit of the erosion rate for a bi-gaussian beam by assuming free expansion of the beam head before the ionization front. Comparison with simulations suggests that half this maximum value can serve as an estimate for the erosion rate. Critical parameters to the erosion rate are discussed.

Berry, M.K.; Blumenfeld, I.; Decker, F.J.; Hogan, M.J.; Ischebeck, R.; Iverson, R.H.; Kirby, N.A.; Siemann, Robert H.; Walz, D.R.; /SLAC; Clayton, C.E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.B.; Zhou, M.; /UCLA; Katsouleas, T.C.; Muggli, P.; Oz, E.; /Southern California U.

2008-01-28T23:59:59.000Z

328

9.01 - Interaction of Ionizing Radiation with Matter  

Science Journals Connector (OSTI)

Abstract The aim of this chapter is to give an overview and try to show how the different interaction probabilities will influence the transport of ionizing radiation through matter. This knowledge is important in different aspects of medical applications of radiation. It has an impact in designing an optimal treatment gantry, in the choice of radiation quality, and of course when determining the absorbed dose distribution in the body. It is also important in diagnostic radiology when optimizing the image quality. Knowledge of the interaction of radiation with matter is also fundamental for understanding the biological effect of radiation and its variation with ionization density. The focus will not be on the basic physics and deriving the different cross sections but on the impact of these cross sections on imaging and therapy in medical physics applications. Ionizing radiation is normally divided into charged particles (previously called directly ionizing radiation) such as leptons, ?-particles, protons and other light ions, and uncharged particles (previously called indirectly ionizing radiation) such as photons (x-rays or ?-rays) and neutrons. This chapter will concentrate on radiation qualities used in radiotherapy, and the main part will be dedicated to electrons and photons with energies up to around 50 MeV and light ions with energies up to 900 MeV per nucleon. The presentation is divided into two main sections, charged particles and photons.

B. Nilsson; A. Brahme

2014-01-01T23:59:59.000Z

329

INDUSTRIAL EFFLUENT TREATMENT USING IONIZING RADIATION COMBINED TO TITANIUM DIOXIDE  

SciTech Connect

The Advanced Oxidation Process (AOP) with OH radicals are the most efficient to mineralize organic compounds, and there are various methods to generate OH radicals as the use of ozone, hydrogen peroxide and ultra-violet radiation and ionizing radiation. The irradiation of aqueous solutions with high-energy electrons results in the excitation and ionizing of the molecules and rapid (10{sup -14} - 10{sup -9} s) formation of reactive intermediates. These reactive species will react with organic compounds present in industrial effluent inducing their decomposition. Titanium dioxide (TiO{sub 2}) catalyzed photoreaction is used to remove a wide range of pollutants in air and water media, combined to UV/VIS light, FeO{sub 2}, and H{sub 2}O{sub 2}, but as far as known there is no report on the combination with ionizing radiation. In some recent studies, the removal of organic pollutants in industrial effluent, such as Benzene, Toluene, and Xylene from petroleum production using ionizing radiation was investigated. It has been ob served that none of the methods can be used individually in wastewater treatment applications with good economics and high degree of energy efficiency. In the present work, the efficiency of ionizing radiation in presence of TiO{sub 2} to treat industrial effluent was evaluated. The main aim to combine these technologies is to improve the efficiency for very hard effluents and to reduce the processing cost for future implementation to large-scale design.

Duarte, C.L.; Oikawa, H.; Mori, M.N.; Sampa, M.H.O.

2004-10-04T23:59:59.000Z

330

Continuum flow sampling mass spectrometer for elemental analysis with an inductively coupled plasma ion source  

SciTech Connect

The sampling of ions from an atmospheric pressure inductively coupled plasma for mass spectrometry (ICP-MS) with a supersonic nozzle and skimmer is shown to follow similar behavior found for neutral beam studies and for ion extraction from other plasmas and flames. In particular, highest ion beam intensity is found if the skimmer tip is close to the Mach disk and at a calculated skimming Knudsen number close to the recommended value of 1. Our ICP-MS instrument with an off-axis detector and conventional cylindrical electrostatic ion focusing in the transition flow regime gives intense count rates of 1 to 5 MHz per mg L/sup -1/ of analyte superimposed on a background of 1 to 10 kHz. The dependence of count rates for metal oxide and doubly charged ions on ICP operating parameters, and sampling interface configuration are discussed for this instrument. A simple method is described for the approximate measurement of the ion energy distribution in ICP-MS. The average ion kinetic energy, kinetic energy spread, and maximum kinetic energy are evaluated from a plot of ion signal as a function of retarding voltage applied to the quadrupole mass analyzer. The effects of plasma operating parameters on ion signals and energies are described. In particular, kinetic energy is a sensitive function of aerosol gas flow rate. This behavior is attributed to a non-thermal, possibly electrical, interaction between the plasma and the sampling interface, which is induced by the presence of the axial channel in the ICP. The interference on the ionization of cobalt by five salts, NaCl, MgCl/sub 2/, NH/sub 4/I, NH/sub 4/Br and NH/sub 4/Cl, in an ICP is first considered theoretically and subsequently the theoretical trends are established experimentally by ICP-MS. The interference trends are found to be in the order of the most easily ionized element in the matrix salt, i.e., Na > Mg > I > Br > Cl.

Olivares, J.A.

1985-06-01T23:59:59.000Z

331

Thermal comfort during surgery  

E-Print Network (OSTI)

THERMAL COMFORT DURING SURGERY A Thesis by DAVID HAROLD MANNING Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1978 Major Subject: Industrial... Engineering THERMAL COMFORT DURING SURGERY A Thesis by DAVID HAROLD MANNING Approved as to style and content by: airman of C it ee Head of Department Member Me er December 1978 ABSTRACT Thermal Comfort During Surgery (December 1978) David Harold...

Manning, David Harold

1978-01-01T23:59:59.000Z

332

Mass Spectrometer: Orbitrap | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

Software (ISIS): A Machine Learning Approach to Tandem Mass Spectral Identification of Lipids. Liquid chromatography-mass spectrometry-based metabolomics has gained importance...

333

Mass Spectrometry | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

and Microfabrication Mass Spectrometry Microscopy Molecular Science Computing NMR and EPR Spectroscopy and Diffraction Subsurface Flow and Transport Mass Spectrometry Systems...

334

Ionization-Based Multi-directional Flow Sensor  

NLE Websites -- All DOE Office Websites (Extended Search)

Ionization-Based Multi-directional Flow Sensor Ionization-Based Multi-directional Flow Sensor Opportunity The Department of Energy's National Energy Technology Laboratory (NETL) is seeking licensing partners interested in implementing United States Patent Number 7,523,673 entitled "Ionization Based Multi-directional Flow Sensor." Disclosed in this patent is NETL's sensor system and process for multi- directional, real-time monitoring of the flow direction and velocity of a gas stream, with minimal pressure drop, such as air flow in a hybrid power generation system. The sensor comprises an ion source accom- panied by a multidirectional ion collection device near the ion source. Possible applications include power generation and weather monitoring. Overview To optimize the performance of certain industrial processes or apparatus,

335

Variable pressure thermal insulating jacket  

DOE Patents (OSTI)

A device for controlled insulation of a thermal device is disclosed. The device includes a thermal jacket with a closed volume able to be evacuated to form an insulating jacket around the thermal source. A getter material is in communication with the closed volume of the thermal jacket. The getter material can absorb and desorb a control gas to control gas pressure in the volume of the thermal jacket to control thermal conductivity in the thermal jacket. 10 figs.

Nelson, P.A.; Malecha, R.F.; Chilenskas, A.A.

1994-09-20T23:59:59.000Z

336

Studies of ground-state dynamics in isolated species by ionization-detected stimulated Raman techniques  

SciTech Connect

First, the author aims to develop methods of nonlinear Raman spectroscopy for application in studies of sparse samples. Second, the author wishes to apply such methods to structural and dynamical studies of species (molecules, complexes, and clusters) in supersonic molecular beams. In the past year, the author has made progress in several areas. The first pertains to the application of mass-selective ionization-detected stimulated Raman spectroscopies (IDSRS) to the size-specific vibrational spectroscopy of solute-solvent{sub n} clusters. The second involves the application of IDSRS methods to studies of jet-cooled benzene clusters. The third pertains to the use of IDSRS methods in the study of intermolecular vibrational transitions in van der Waals complexes.

Felker, P.M. [Univ. of California, Los Angeles (United States)

1993-12-01T23:59:59.000Z

337

NANO REVIEW Open Access Thermal conductivity and thermal boundary  

E-Print Network (OSTI)

NANO REVIEW Open Access Thermal conductivity and thermal boundary resistance of nanostructures and the thermal transport prop- erties is a key point to design materials with preferred thermal properties with the heat dissipation on them. The influence of the interfacial roughness on the thermal conductivity

Boyer, Edmond

338

Ionized Iron Lines in X-ray Reflection Spectra  

E-Print Network (OSTI)

We present results from new calculations of the X-ray reflection spectrum from ionized accretion discs. These computations improve on our previous models by including the condition of hydrostatic balance in the vertical direction, following the work of Nayakshin, Kazanas & Kallman. We find that an ionized Fe K$\\alpha$ line is prominent in the reflection spectra for a wide variety of physical conditions. The results hold for both gas and radiation pressure dominated discs and when the metal abundances have been varied.

D. R. Ballantyne; R. R. Ross; A. C. Fabian

2001-02-15T23:59:59.000Z

339

Role of Photoexcitation and Field Ionization in the Measurement of Accurate Oxide Stoichiometry by Laser-Assisted Atom Probe Tomography  

SciTech Connect

Pulsed lasers extend the high spatial and mass resolution of atom probe tomography (APT) to non-conducting materials, such as oxides. For prototypical metal oxide MgO, measured stoichiometry depends strongly upon pulse energy and applied voltage. Very low laser energies (0.02 pJ) and high electric fields yield optimal stoichiometric accuracy, attributed to the field-dependent ionization of photo-desorbed O or O2 neutrals. This emphasizes the importance of considering electronic excitations in APT analysis of oxides ionic materials.

Devaraj, Arun; Colby, Robert J.; Hess, Wayne P.; Perea, Daniel E.; Thevuthasan, Suntharampillai

2013-03-06T23:59:59.000Z

340

Thermal Insulation of Houses  

Science Journals Connector (OSTI)

... THE Thermal Insulation (Dwellings) Bill which Mr. G. Nabarro introduced into the House of Commons on ... , sponsored by members of both major political parties, extends the principle of the Thermal Insulation (Industrial Buildings) Act of July 1957 to all new dwelling houses built in the ...

1958-02-22T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Mechanical Engineering & Thermal Group  

E-Print Network (OSTI)

Mechanical Engineering & Thermal Group The Mechanical Engineering (ME) & Thermal Group at LASP has, and ground- based mechanical systems. Instrument Design Building on decades of design experience that has evolved with the complexity of instrument design demands, LASP mechanical engineers develop advanced

Mojzsis, Stephen J.

342

Mass spectrometric immunoassay  

DOE Patents (OSTI)

Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

Nelson, Randall W; Williams, Peter; Krone, Jennifer Reeve

2013-07-16T23:59:59.000Z

343

Mass spectrometric immunoassay  

DOE Patents (OSTI)

Rapid mass spectrometric immunoassay methods for detecting and/or quantifying antibody and antigen analytes utilizing affinity capture to isolate the analytes and internal reference species (for quantification) followed by mass spectrometric analysis of the isolated analyte/internal reference species. Quantification is obtained by normalizing and calibrating obtained mass spectrum against the mass spectrum obtained for an antibody/antigen of known concentration.

Nelson, Randall W (Phoenix, AZ); Williams, Peter (Phoenix, AZ); Krone, Jennifer Reeve (Granbury, TX)

2007-12-04T23:59:59.000Z

344

Tandem Mass Spectrometry for the Direct Assay of Lysosomal Enzymes in  

E-Print Network (OSTI)

. Mucopolysaccharidosis type I (MPS-I)4 is a lysosomal storage disorder caused by the deficiency of -L- iduronidase (Id-Scheie syndromes. IdA is essential for the degradation within lysosomes of the glycosamino- glycans dermatan recognition of MPS-I. Flu- orometric, radiometric, and electrospray ionization­ tandem mass spectrometry (ESI

Gelb, Michael

345

Thermal Recovery Methods  

SciTech Connect

Thermal Recovery Methods describes the basic concepts of thermal recovery and explains the injection patterns used to exploit reservoir conditions. Basic reservoir engineering is reviewed with an emphasis on changes in flow characteristics caused by temperature. The authors discuss an energy balance for steam and combustion drive, and they explain in situ reactions. Heat loss, combustion drive, and steam displacement also are examined in detail, as well as cyclic steam injection, downhole ignition, well heating, and low-temperature oxidation. Contents: Thermal processes; Formation and reservoir evaluations; Well patterns and spacing; Flow and process equations; Laboratory simulation of thermal recovery; Heat loss and transmission; Displacement and production; Equipment; Basic data for field selection; Laboratory evaluation of combustion characteristics; Thermal properties of reservoirs and fluids.

White, P.D.; Moss, J.T.

1983-01-01T23:59:59.000Z

346

Tunable thermal link  

DOE Patents (OSTI)

Disclosed is a device whereby the thermal conductance of a multiwalled nanostructure such as a multiwalled carbon nanotube (MWCNT) can be controllably and reversibly tuned by sliding one or more outer shells with respect to the inner core. As one example, the thermal conductance of an MWCNT dropped to 15% of the original value after extending the length of the MWCNT by 190 nm. The thermal conductivity returned when the tube was contracted. The device may comprise numbers of multiwalled nanotubes or other graphitic layers connected to a heat source and a heat drain and various means for tuning the overall thermal conductance for applications in structure heat management, heat flow in nanoscale or microscale devices and thermal logic devices.

Chang, Chih-Wei; Majumdar, Arunava; Zettl, Alexander K.

2014-07-15T23:59:59.000Z

347

Solar thermal aircraft  

DOE Patents (OSTI)

A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

Bennett, Charles L. (Livermore, CA)

2007-09-18T23:59:59.000Z

348

Standard test method for analysis of isotopic composition of uranium in nuclear-grade fuel material by quadrupole inductively coupled plasma-mass spectrometry  

E-Print Network (OSTI)

1.1 This test method is applicable to the determination of the isotopic composition of uranium (U) in nuclear-grade fuel material. The following isotopic weight percentages are determined using a quadrupole inductively coupled plasma-mass spectrometer (Q-ICP-MS): 233U, 234U, 235U, 236U, and 238U. The analysis can be performed on various material matrices after acid dissolution and sample dilution into water or dilute nitric (HNO3) acid. These materials include: fuel product, uranium oxide, uranium oxide alloys, uranyl nitrate (UNH) crystals, and solutions. The sample preparation discussed in this test method focuses on fuel product material but may be used for uranium oxide or a uranium oxide alloy. Other preparation techniques may be used and some references are given. Purification of the uranium by anion-exchange extraction is not required for this test method, as it is required by other test methods such as radiochemistry and thermal ionization mass spectroscopy (TIMS). This test method is also described i...

American Society for Testing and Materials. Philadelphia

2000-01-01T23:59:59.000Z

349

Thermal Performance of Phase-Change Wallboard for Residential Cooling  

NLE Websites -- All DOE Office Websites (Extended Search)

6 6 Thermal Performance of Phase-Change Wallboard for Residential Cooling Cooling residential buildings in milder climates contributes significantly to peak demand mainly because of poor load factors. Peak cooling load determines the size of equipment and the cooling source. Several measures reduce cooling-system size and allow the use of lower-energy cooling sources; they include incorporating exterior walls or other elements that effectively shelter interiors from outside heat and cold, and providing thermal mass, to cool interior spaces during the day by absorbing heat and warm them at night as the mass discharges its heat. Thermal mass features may be used for storage only or serve as structural elements. Concrete, steel, adobe, stone, and brick all satisfy requirements

350

A simple algorithm improves mass accuracy to 50-100 ppm for delayed extraction linear MALDI-TOF mass spectrometry  

SciTech Connect

A simple mathematical technique for improving mass calibration accuracy of linear delayed extraction matrix assisted laser desorption ionization time-of-flight mass spectrometry (DE MALDI-TOF MS) spectra is presented. The method involves fitting a parabola to a plot of Dm vs. mass data where Dm is the difference between the theoretical mass of calibrants and the mass obtained from a linear relationship between the square root of m/z and ion time of flight. The quadratic equation that describes the parabola is then used to correct the mass of unknowns by subtracting the deviation predicted by the quadratic equation from measured data. By subtracting the value of the parabola at each mass from the calibrated data, the accuracy of mass data points can be improved by factors of 10 or more. This method produces highly similar results whether or not initial ion velocity is accounted for in the calibration equation; consequently, there is no need to depend on that uncertain parameter when using the quadratic correction. This method can be used to correct the internally calibrated masses of protein digest peaks. The effect of nitrocellulose as a matrix additive is also briefly discussed, and it is shown that using nitrocellulose as an additive to a CHCA matrix does not significantly change initial ion velocity but does change the average position of ions relative to the sample electrode at the instant the extraction voltage is applied.

Hack, Christopher A.; Benner, W. Henry

2001-10-31T23:59:59.000Z

351

Plasma ionization by annularly bounded helicon waves Masayuki Yanoa  

E-Print Network (OSTI)

Plasma ionization by annularly bounded helicon waves Masayuki Yanoa and Mitchell L. R. Walkerb and magnetic fields is derived with respect to the boundary conditions of a coaxial helicon plasma source by comparison with the standard cylindrical helicon plasma source. Further, a parametric study of source length

Walker, Mitchell

352

Optically-ionized plasma recombination x-ray lasers  

SciTech Connect

Design studies for recombination x-ray lasers based on plasmas ionized by high intensity, short pulse optical lasers are presented. Transient lasing on n = 3 to n = 2 transitions in Lithium-like Neon allows for moderately short wavelengths ({le} 100{angstrom}) without requiring ionizing intensities associated with relativistic electron quiver energies. The electron energy distribution following the ionizing pulse affects directly the predicted gains for this resonance transition. Efficiencies of 10{sup {minus}6} or greater are found for plasma temperatures in the vicinity of 40 eV. Simulation studies of parametric heating phenomena relating to stimulated Raman and Compton scattering are presented. For electron densities less than about 2.5 {times} 10{sup 20} cm{sup {minus}3} and peak driver intensity of 2 {times} 10{sup 17} W/cm{sup 2} at 0.25 {mu}m with pulse length of 100 fsec, the amount of electron heating is found to be marginally significant. For Lithium-like Aluminum, the required relativistic ionizing intensity gives excessive electron heating and reduced efficiency, thereby rendering this scheme impractical for generating shorter wavelength lasing ({le} 50{angstrom}) in the transient case. Following the transient lasing phase, a slow hydrodynamic expansion into the surrounding cool plasma is accompanied by quasi-static gain on the n = 4 to n = 3 transition in Lithium-like Neon. Parametric heating effects on gain optimization in this regime are also discussed. 18 refs., 6 figs.

Amendt, P.; Eder, D.C.; Wilks, S.C.; Dunning, M.J.; Keane, C.J.

1991-01-18T23:59:59.000Z

353

Cell cycle responses to low-dose ionizing radiation.  

Science Journals Connector (OSTI)

...47, 2006] 5178 Low-dose hyper-radiosensitivity...radiosensitivity of cells to doses of ionizing radiation less than 0.5 Gy...connection between low-dose HRS survival, Ataxia...the low dose radiation range (0-1 Gy). MR4 cells...

Sarah A. Krueger; George D. Wilson; Michael C. Joiner; and Brian Marples

2006-04-15T23:59:59.000Z

354

The Inactivation of $\\alpha$-Chymotrypsin by Ionizing Radiations  

Science Journals Connector (OSTI)

...Chymotrypsin by Ionizing Radiations J. A. V. Butler...studied over a range of concentrations...where D is the dose required to cause...air over a wide range of concentrations...by varying the dose rate of the electron...over a very wide range. An enhanced...

1960-01-01T23:59:59.000Z

355

Sensitivity of aflatoxin b1 to ionizing radiation.  

Science Journals Connector (OSTI)

...activity with respective doses of 2.5, 5, 10...irradiation aflatoxin B1 dose of: in upper layediteionre...in foodstuffs may range from levels of 0...with an irradiation dose of10 kGy (the maximum...its sensitivity to ionizing radiation. When aflatoxin...

P J Van Dyck; P Tobback; M Feyes; H van de Voorde

1982-06-01T23:59:59.000Z

356

Toxicity of Pasteurella tularensis Killed by Ionizing Radiation  

Science Journals Connector (OSTI)

...to 106 r of y-radiation. When injected...suspension. Lethal doses of newly prepared...by exposure to ionizing radia- tion induced...to 106 r of y-radiation from a 60Co source at a dose rate of approximately...only in a limited range of dilutions...

Marshall E. Landay; George G. Wright; James D. Pulliam; Milton J. Finegold

1968-09-01T23:59:59.000Z

357

Project Lyman: Quantifying 11 Gyrs of Metagalactic Ionizing Background Evolution  

E-Print Network (OSTI)

The timing and duration of the reionization epoch is crucial to the emergence and evolution of structure in the universe. The relative roles that star-forming galaxies, active galactic nuclei and quasars play in contributing to the metagalactic ionizing background across cosmic time remains uncertain. Deep quasar counts provide insights into their role, but the potentially crucial contribution from star-formation is highly uncertain due to our poor understanding of the processes that allow ionizing radiation to escape into the intergalactic medium (IGM). The fraction of ionizing photons that escape from star-forming galaxies is a fundamental free parameter used in models to "fine-tune" the timing and duration of the reionization epoch that occurred somewhere between 13.4 and 12.7 Gyrs ago (redshifts between 12 > z > 6). However, direct observation of Lyman continuum (LyC) photons emitted below the rest frame \\ion{H}{1} ionization edge at 912 \\AA\\ is increasingly improbable at redshifts z > 3, due to the stead...

McCandliss, Stephan R; Bergvall, Nils; Bianchi, Luciana; Bridge, Carrie; Bogosavljevic, Milan; Cohen, Seth H; Deharveng, Jean-Michel; Dixon, W Van Dyke; Ferguson, Harry; Friedman, Peter; Hayes, Matthew; Howk, J Christopher; Inoue, Akio; Iwata, Ikuru; Kaiser, Mary Elizabeth; Kriss, Gerard; Kruk, Jeffrey; Kutyrev, Alexander S; Leitherer, Claus; Meurer, Gerhardt R; Prochaska, Jason X; Sonneborn, George; Stiavelli, Massimo; Teplitz, Harry I; Windhorst, Rogier A

2012-01-01T23:59:59.000Z

358

High resolution resonance ionization imaging detector and method  

DOE Patents (OSTI)

A resonance ionization imaging device (RIID) and method for imaging objects using the RIID are provided, the RIID system including a RIID cell containing an ionizable vapor including monoisotopic atoms or molecules, the cell being positioned to intercept scattered radiation of a resonance wavelength .lambda..sub.1 from the object which is to be detected or imaged, a laser source disposed to illuminate the RIID cell with laser radiation having a wavelength .lambda..sub.2 or wavelengths .lambda..sub.2, .lambda..sub.3 selected to ionize atoms in the cell that are in an excited state by virtue of having absorbed the scattered resonance laser radiation, and a luminescent screen at the back surface of the RIID cell which presents an image of the number and position of charged particles present in the RIID cell as a result of the ionization of the excited state atoms. The method of the invention further includes the step of initially illuminating the object to be detected or imaged with a laser having a wavelength selected such that the object will scatter laser radiation having the resonance wavelength .lambda..sub.1.

Winefordner, James D. (Gainesville, FL); Matveev, Oleg I. (Gainesville, FL); Smith, Benjamin W. (Gainesville, FL)

1999-01-01T23:59:59.000Z

359

Parametric-resonance ionization cooling of muon beams  

SciTech Connect

Parametric-resonance Ionization Cooling (PIC) is proposed as the final 6D cooling stage of a high-luminosity muon collider. Combining muon ionization cooling with parametric resonant dynamics should allow an order of magnitude smaller final equilibrium transverse beam emittances than conventional ionization cooling alone. In this scheme, a half-integer parametric resonance is induced in a cooling channel causing the beam to be naturally focused with the period of the channel's free oscillations. Thin absorbers placed at the focal points then cool the beam's angular divergence through the usual ionization cooling mechanism where each absorber is followed by RF cavities. A special continuous-field twin-helix magnetic channel with correlated behavior of the horizontal and vertical betatron motions and dispersion was developed for PIC. We present the results of modeling PIC in such a channel using GEANT4/G4beamline. We discuss the challenge of precise beam aberration control from one absorber to another over a wide angular spread.

Morozov, V. S.; Derbenev, Ya. S.; Afanasev, A.; Johnson, R. P.; Erdelyi, B.; Maloney, J. A. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Muons, Inc., Batavia, Illinois 60510 (United States) and George Washington University, Washington, D.C. 20052 (United States); Muons, Inc., Batavia, Illinois 60510 (United States); Northern Illinois University, DeKalb, Illinois 60115 (United States)

2012-12-21T23:59:59.000Z

360

Parametric-Resonance Ionization Cooling of Muon Beams  

SciTech Connect

Parametric-resonance Ionization Cooling (PIC) is proposed as the final 6D cooling stage of a high-luminosity muon collider. Combining muon ionization cooling with parametric resonant dynamics should allow an order of magnitude smaller final equilibrium transverse beam emittances than conventional ionization cooling alone. In this scheme, a half-integer parametric resonance is induced in a cooling channel causing the beam to be naturally focused with the period of the channel's free oscillations. Thin absorbers placed at the focal points then cool the beam?s angular divergence through the usual ionization cooling mechanism where each absorber is followed by RF cavities. A special continuous-field twin-helix magnetic channel with correlated behavior of the horizontal and vertical betatron motions and dispersion was developed for PIC. We present the results of modeling PIC in such a channel using GEANT4/ G4 beamline. We discuss the challenge of precise beam aberration control from one absorber to another over a wide angular spread.

Morozov, V. S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Derbenev, Ya. S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Afanasev, A. [Muons, Inc., Batavia, IL (United States) and George Washington University, Washington, D.C. (United States); Johnson, R. P. [Muons, Inc., Batavia, IL (United States); Erdelyi, B. [Northern Illinois University, DeKalb, IL (United States); Maloney, J. A. [Northern Illinois University, DeKalb, IL (United States)

2012-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Femtosecond laser nanomachining initiated by ultraviolet multiphoton ionization  

E-Print Network (OSTI)

Femtosecond laser nanomachining initiated by ultraviolet multiphoton ionization Xiaoming Yu,1) femtosecond laser pulse initiated by an ultraviolet (UV) pulse. With both pulses at a short (~60 fs) delay.g. XUV and X-ray, with the required fluence below their normal threshold. ©2013 Optical Society

Van Stryland, Eric

362

Recent Advances in Thermionic Ionization Detection for Gas Chromatography  

Science Journals Connector (OSTI)

......and catalytic combustion modifier/thermionic...be comparable to hydrocarbons by a judicious selection...because the flame heat w o u l d otherwise...elec tronegative combustion products by means...the bulk o f the hydrocarbon ionization pro duced...The applications data presented in this......

P.L. Patterson

1986-02-01T23:59:59.000Z

363

production under ionizing radiation in aluminoborosilicate glasses by EPR spectroscopy.  

E-Print Network (OSTI)

1 Ti3+ production under ionizing radiation in aluminoborosilicate glasses by EPR spectroscopy. P irradiation of Ti4+ ions in aluminoborosilicate glasses have been studied by EPR spectroscopy at 20 K of the Ti3+ ion EPR spectra has shown three different Ti3+ environment attributed to one [VI] Ti3+ and two

Paris-Sud XI, Université de

364

Ionization monitor with improved ultra-high megohm resistor  

DOE Patents (OSTI)

An ionization monitor measures extremely small currents using a resistor containing a beta emitter to generate ion-pairs which are collected as current when the device is used as a feedback resistor in an electrometer circuit. By varying the amount of beta emitter, the resistance of the resistor may be varied.

Burgess, Edward T. (Carlisle, OH)

1988-11-05T23:59:59.000Z

365

Enhanced performance of high temperature aluminate cementitious materials incorporated with Cu powders for thermal energy storage  

Science Journals Connector (OSTI)

Abstract Cementitious materials have been extensively developed in thermal energy storage system of solar thermal power. This paper deals with the volume heat capacity, thermal conductivity, thermal expansion coefficient, and compressive strength of aluminate cementitious thermal energy storage materials with the addition of metal Cu powders. The specimens were subjected to heat-treatment at 105, 350, and 900 °C, respectively. In the heating process, Cu powders gradually oxidized to Cu2O and CuO, providing a so-called mass compensation mechanism for the composite paste. Meanwhile, it indicates that volume heat capacity and thermal conductivity both increase with increasing Cu powders content and decrease with the rising temperature. The optimum thermal properties were obtained at 15 wt% Cu powders loading. In addition, Calorimetric Test, XRD, TG–DSC, and MIP are performed for characterizing the hydration rates, the phases, the mass/heat evolution, and the pore distribution, respectively.

Huiwen Yuan; Yu Shi; Chunhua Lu; Zhongzi Xu; Yaru Ni; Xianghui Lan

2015-01-01T23:59:59.000Z

366

High-Temperature Thermal Array for Next Generation Solar Thermal...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Thermal Array for Next Generation Solar Thermal Power Production Award Number: DE-EE00025828 Report Date: March 15, 2013 PI: Stephen Obrey * Technical approach is focused on...

367

Characterization of Cell Cycle Checkpoint Responses after Ionizing Radiation in Nijmegen Breakage Syndrome Cells  

Science Journals Connector (OSTI)

...events leading to G, and G2 arrests following ionizing radiation is abnormal in cells from AT patients. p53 protein up- regulation following low doses of ionizing radiation ranges from delayed and reduced to completely absent...

Vikky Yamazaki; Rolf-Dieter Wegner; and Cordula U. Kirchgessner

1998-06-01T23:59:59.000Z

368

Enhanced Sensitivity of the RET Proto-Oncogene to Ionizing Radiation In vitro  

Science Journals Connector (OSTI)

...the RET sensitivity to ionizing radiation exposure, and to elucidate...were first exposed to ionizing radiation, electrophoresed in...Table 1 Table 1. Range of tail moment in non...for comet Radiation dose Cell line Range of tail...

Claudia Béu Volpato; Minerva Martínez-Alfaro; Raffaella Corvi; Coralie Gabus; Sylvie Sauvaigo; Pietro Ferrari; Elena Bonora; Alessandro De Grandi; and Giovanni Romeo

2008-11-01T23:59:59.000Z

369

Extremely Low Dose Ionizing Radiation Up-regulates CXC Chemokines in Normal Human Fibroblasts  

Science Journals Connector (OSTI)

...with radiation exposure (1). Ionizing radiation at moderate and higher doses (0.1-10 Gy) can produce DNA strand...death. Studies of mutants sensitive to ionizing radiation at this range of doses have revealed that the responsible genes...

Akira Fujimori; Ryuichi Okayasu; Hiroshi Ishihara; Satoshi Yoshida; Kiyomi Eguchi-Kasai; Kumie Nojima; Satoru Ebisawa; and Sentaro Takahashi

2005-11-15T23:59:59.000Z

370

TWO-DIMENSIONAL RADIATIVE MAGNETOHYDRODYNAMIC SIMULATIONS OF THE IMPORTANCE OF PARTIAL IONIZATION IN THE CHROMOSPHERE  

SciTech Connect

The bulk of the solar chromosphere is weakly ionized and interactions between ionized particles and neutral particles likely have significant consequences for the thermodynamics of the chromospheric plasma. We investigate the importance of introducing neutral particles into the MHD equations using numerical 2.5D radiative MHD simulations obtained with the Bifrost code. The models span the solar atmosphere from the upper layers of the convection zone to the low corona, and solve the full MHD equations with non-gray and non-LTE radiative transfer, and thermal conduction along the magnetic field. The effects of partial ionization are implemented using the generalized Ohm's law, i.e., we consider the effects of the Hall term and ambipolar diffusion in the induction equation. The approximations required in going from three fluids to the generalized Ohm's law are tested in our simulations. The Ohmic diffusion, Hall term, and ambipolar diffusion show strong variations in the chromosphere. These strong variations of the various magnetic diffusivities are absent or significantly underestimated when, as has been common for these types of studies, using the semi-empirical VAL-C model as a basis for estimates. In addition, we find that differences in estimating the magnitude of ambipolar diffusion arise depending on which method is used to calculate the ion-neutral collision frequency. These differences cause uncertainties in the different magnetic diffusivity terms. In the chromosphere, we find that the ambipolar diffusion is of the same order of magnitude or even larger than the numerical diffusion used to stabilize our code. As a consequence, ambipolar diffusion produces a strong impact on the modeled atmosphere. Perhaps more importantly, it suggests that at least in the chromospheric domain, self-consistent simulations of the solar atmosphere driven by magnetoconvection can accurately describe the impact of the dominant form of resistivity, i.e., ambipolar diffusion. This suggests that such simulations may be more realistic in their approach to the lower solar atmosphere (which directly drives the coronal volume) than previously assumed.

Martinez-Sykora, Juan; De Pontieu, Bart; Hansteen, Viggo, E-mail: j.m.sykora@astro.uio.no [Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 (United States)

2012-07-10T23:59:59.000Z

371

COMPRESSIBLE STREAMING INSTABILITIES IN ROTATING THERMAL VISCOUS OBJECTS  

SciTech Connect

We study electromagnetic streaming instabilities in thermal viscous regions of rotating astrophysical objects, such as protostellar and protoplanetary magnetized accretion disks, molecular clouds, their cores, and elephant trunks. The obtained results can also be applied to any regions of interstellar medium, where different equilibrium velocities between charged species can arise. We consider a weakly and highly ionized three-component plasma consisting of neutrals and magnetized electrons and ions. The vertical perturbations along the background magnetic field are investigated. The effect of perturbation of collisional frequencies due to density perturbations of species is taken into account. The growth rates of perturbations are found in a wide region of wave number spectrum for media, where the thermal pressure is larger than the magnetic pressure. It is shown that in cases of strong collisional coupling of neutrals with ions the contribution of the viscosity is negligible.

Nekrasov, A. K., E-mail: anatoli.nekrassov@t-online.d [Institute of Physics of the Earth, Russian Academy of Sciences, 123995 Moscow (Russian Federation)

2009-10-10T23:59:59.000Z

372

Nonlinear dynamics of ionization stabilization of atoms in intense laser fields  

E-Print Network (OSTI)

We revisit the stabilization of ionization of atoms subjected to a superintense laser pulse using nonlinear dynamics. We provide an explanation for the lack of complete ionization at high intensity and for the decrease of the ionization probability as intensity is increased. We investigate the role of each part of the laser pulse (ramp-up, plateau, ramp-down) in this process. We emphasize the role of the choice for the ionization criterion, energy versus distance criterion.

Michael Norman; C. Chandre; T. Uzer; Peijie Wang

2014-12-06T23:59:59.000Z

373

Theory of delayed thermal fluorescence  

Science Journals Connector (OSTI)

A theory of nonradiative thermal activation involved in delayed thermal fluorescence has been developed from the viewpoint of the breakdown of the Born-Oppenheimer adiabatic approximation.

S. H. Lin

1971-01-01T23:59:59.000Z

374

Thermal insulations using vacuum panels  

DOE Patents (OSTI)

Thermal insulation vacuum panels are formed of an inner core of compressed low thermal conductivity powders enclosed by a ceramic/glass envelope evaluated to a low pressure.

Glicksman, Leon R. (Lynnfield, MA); Burke, Melissa S. (Pittsburgh, PA)

1991-07-16T23:59:59.000Z

375

Demand Shifting with Thermal Mass in Light and Heavy Mass Commercial Buildings  

E-Print Network (OSTI)

on the cooling load and cooling power. Temperatures in thestrategies, CSSC Figure 3. Cooling power reduction on pre-the warm days. The power usages for cooling on the baseline

Xu, Peng

2010-01-01T23:59:59.000Z

376

A model of the thermal processing of particles in solar nebula shocks: Application to the cooling rates of chondrules  

E-Print Network (OSTI)

A model of the thermal processing of particles in solar nebula shocks: Application to the cooling for the thermal processing of particles in shock waves typical of the solar nebula. This shock model improves are accounted for in their ef fects on the mass, momentum and energy fluxes. Also, besides thermal exchange

Connolly Jr, Harold C.

377

Thermally driven circulation  

E-Print Network (OSTI)

Several problems connected by the theme of thermal forcing are addressed herein. The main topic is the stratification and flow field resulting from imposing a specified heat flux on a fluid that is otherwise confined to a ...

Nelken, Haim

1987-01-01T23:59:59.000Z

378

Manipulation of Thermal Phonons  

E-Print Network (OSTI)

to manipulate the behavior of phonons is crucial for both energy applications and the cooling of integrated circuits. A novel class of artificially periodic structured materials — phononic crystals — might make manipulation of thermal phonons possible. In many...

Hsu, Chung-Hao

2013-03-28T23:59:59.000Z

379

Solar Thermal Energy Storage  

Science Journals Connector (OSTI)

Various types of thermal energy storage systems are introduced and their importance and desired characteristics are outlined. Sensible heat storage, which is one of the most commonly used storage systems in pract...

E. Paykoç; S. Kakaç

1987-01-01T23:59:59.000Z

380

Contact thermal lithography  

E-Print Network (OSTI)

Contact thermal lithography is a method for fabricating microscale patterns using heat transfer. In contrast to photolithography, where the minimum achievable feature size is proportional to the wavelength of light used ...

Schmidt, Aaron Jerome, 1979-

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Neutron stars - thermal emitters  

E-Print Network (OSTI)

Confronting theoretical models with observations of thermal radiation emitted by neutron stars is one of the most important ways to understand the properties of both, superdense matter in the interiors of the neutron stars and dense magnetized plasmas in their outer layers. Here we review the theory of thermal emission from the surface layers of strongly magnetized neutron stars, and the main properties of the observational data. In particular, we focus on the nearby sources for which a clear thermal component has been detected, without being contaminated by other emission processes (magnetosphere, accretion, nebulae). We also discuss the applications of the modern theoretical models of the formation of spectra of strongly magnetized neutron stars to the observed thermally emitting objects.

Potekhin, A Y; Pons, J A

2014-01-01T23:59:59.000Z

382

Physiological Responses of the Hyperthermophilic Archaeon “Pyrococcus abyssi” to DNA Damage Caused by Ionizing Radiation  

Science Journals Connector (OSTI)

...Damage Caused by Ionizing Radiation Edmond Jolivet 1 Corresponding...Fukuoka 812-8581, Japan The mechanisms by which...temperature and/or ionizing radiation. The hyperthermophilic...Matsunaga thanks the Japan Society for the Promotion...resistant to ionizing radiation? Trends Microbiol...

Edmond Jolivet; Fujihiko Matsunaga; Yoshizumi Ishino; Patrick Forterre; Daniel Prieur; Hannu Myllykallio

2003-07-01T23:59:59.000Z

383

Ionizing Radiation-induced, Mitochondria-dependent Generation of Reactive Oxygen/Nitrogen  

Science Journals Connector (OSTI)

...exposing cells to ionizing radiation. In the 1-10 Gy dose range, the amount...demonstrated that ionizing radiation in the therapeutic dose range stimulates a...exposing cells to ionizing radiation. In the 1-10 Gy dose range, the amount...

J. Kevin Leach; Glenn Van Tuyle; Peck-Sun Lin; Rupert Schmidt-Ullrich; and Ross B. Mikkelsen

2001-05-15T23:59:59.000Z

384

Physical and biological properties of U.S. standard endotoxin EC after exposure to ionizing radiation.  

Science Journals Connector (OSTI)

...in the UV range, radiation treatment...pattern. Dose-related...effects of the ionizing radiation...milligram-per-milliliter range) (13...in the UV range, we found...ioniz- ing radiation. Regarding...effective, dose- dependent...EXPOSED TO IONIZING RADIATION...

G Csako; R J Elin; H D Hochstein; C M Tsai

1983-07-01T23:59:59.000Z

385

MACHINE LEARNING FOR IDENTIFICATION OF SOURCES OF IONIZING RADIATION DURING SPACE MISSIONS  

E-Print Network (OSTI)

MACHINE LEARNING FOR IDENTIFICATION OF SOURCES OF IONIZING RADIATION DURING SPACE MISSIONS Ricardo for the automated identification and classification of tracks of ionizing radiation during space missions. The tracks of ionizing radiation are mea- sured by the hybrid semiconductor Medipix2 pixel de- tector system

Vilalta, Ricardo

386

Discovering Clinical Biomarkers of Ionizing Radiation Exposure with Serum Proteomic Analysis  

Science Journals Connector (OSTI)

...with a wide range of diagnoses and radiation treatment...and during ionizing radiation...from low dose-volume...of a wide range of diagnoses...volume, and dose of radiotherapy...exposed to ionizing radiation between the...with a wide range of diagnoses and radiation treatment...and during ionizing radiation...from low dose-volume...

Cynthia Ménard; Donald Johann; Mark Lowenthal; Thierry Muanza; Mary Sproull; Sally Ross; James Gulley; Emanuel Petricoin; C. Norman Coleman; Gordon Whiteley; Lance Liotta; and Kevin Camphausen

2006-02-01T23:59:59.000Z

387

Ionizing Radiation Effects on CMOS Imagers Manufactured in Deep Submicron Process  

E-Print Network (OSTI)

, ionizing radiation, total dose, dark current, STI, hardening by design, RHDB 1. INTRODUCTION IonizingIonizing Radiation Effects on CMOS Imagers Manufactured in Deep Submicron Process Vincent Goiffona a large dynamic range. This can significantly impact the radiation hardness of "in-pixel" devices which

Mailhes, Corinne

388

Response of single cells and cell extracts to irradiation as detected by time-of-flight secondary ion mass spectrometry (ToF-SIMS)  

Science Journals Connector (OSTI)

...secondary ion mass spectrometry (ToF-SIMS) Mark G. Knize Kuang Jen Wu David L...Secondary Ion Mass Spectrometry (ToF-SIMS) uses an ion beam to desorb and ionize...Together these experiments show that ToF-SIMS analysis of single cells can be used to...

Mark G. Knize; Kuang Jen Wu; David L. Shattuck; Ligang Wu; Erik J. Nelson; Jennifer L. Montgomery; Cynthia B. Thomas; James S. Felton; Kristen S. Kulp

2005-05-01T23:59:59.000Z

389

Thermal decomposition of charring materials  

SciTech Connect

Experimental techniques and methods were developed to investigate the transient process of wood pyrolysis under different levels of external radiation, moisture content of the wood sample, and oxygen concentration of the ambient atmosphere. A unique small-scale combustion-wind tunnel was constructed to conduct the pyrolysis experiments and to obtain the time dependent gasification mass flux, surface and in-depth temperatures, and evolved products of pyrolysis (CO, CO{sub 2}, H{sub 2}O, and total hydrocarbons (THC)) for thermally thick samples of Douglas-fir. Experiments were performed both in inert atmosphere (nitrogen), and in air at several different heat fluxes and three different moisture contents of wood. Time dependent empirical chemical composition, char yield, and the heat of combustion of the pyrolysis products were determined. The experimental results indicate that the presence of moisture reduces the pyrolysis mass flux and delays the occurrence of its maxima. Presence of oxygen drastically increases the pyrolysis mass flux but its effect specially at lower temperatures depends on the experimental conditions such as the boundary layer thickness over the wood surface. Char yield, chemical composition of the volatiles, and the heat of combustion were found to vary during the pyrolysis process and with changes in the environmental conditions and wood moisture content. The pyrolysis temperature assumption often used for the simplified modeling of wood pyrolysis was examined in detail by considering two otherwise identical models; one with infinitely fast decomposition kinetics and the other with finite rate chemistry. It was concluded that the pyrolysis temperature is not a material property and different pyrolysis temperatures are needed for every problem.

Nurbakhsh, S.

1989-01-01T23:59:59.000Z

390

Texas Thermal Comfort Report  

NLE Websites -- All DOE Office Websites (Extended Search)

thermal comfort thermal comfort Too often, the systems in our houses are both physically and intellectually inaccessible. In the SNAP House, HVAC components are integrated into the overall structure, and act as an experiential threshold between public and private spaces. They are located in a central, structural chase that supports the clerestory and gives the systems a functional presence within the interior. Each individual component is contained within a single chase

391

Photovoltaic-thermal collectors  

DOE Patents (OSTI)

A photovoltaic-thermal solar cell including a semiconductor body having antireflective top and bottom surfaces and coated on each said surface with a patterned electrode covering less than 10% of the surface area. A thermal-absorbing surface is spaced apart from the bottom surface of the semiconductor and a heat-exchange fluid is passed between the bottom surface and the heat-absorbing surface.

Cox, III, Charles H. (Carlisle, MA)

1984-04-24T23:59:59.000Z

392

EMSL - Mass Spectrometry  

NLE Websites -- All DOE Office Websites (Extended Search)

mass-spectrometry Proteomics Capabilities High resolution and mass accuracy Fourier-transform ion cyclotron resonance (FT-ICR) spectrometers, from 6 Tesla (T) to 15T and 21T in...

393

mass communication advertising &  

E-Print Network (OSTI)

mass communication advertising & public relations introduction. Graduate programs in the Department of Mass Communication, Advertising, and Public Relations provide an entry to a wide spectrum of careers the opportunity to create content, campaigns, strategy, and research in public relations, advertising

Finzi, Adrien

394

Nuclear and Non-Ionizing Energy-loss of Electrons with Low and Relativistic Energies in Materials and Space Environment  

E-Print Network (OSTI)

The treatment of the electron-nucleus interaction based on the Mott differential cross section was extended to account for effects due to screened Coulomb potentials, finite sizes and finite rest masses of nuclei for electrons above 200 keV and up to ultra high energies. This treatment allows one to determine both the total and differential cross sections, thus, subsequently to calculate the resulting nuclear and non-ionizing stopping powers. Above a few hundreds of MeV, neglecting the effect due to finite rest masses of recoil nuclei the stopping power and NIEL result to be largely underestimated; while, above a few tens of MeV the finite size of the nuclear target prevents a further large increase of stopping powers which approach almost constant values.

Boschini, M J; Gervasi, M; Giani, S; Grandi, D; Ivanchenko, V; Nieminem, P; Pensotti, S; Rancoita, P G; Tacconi, M

2011-01-01T23:59:59.000Z

395

Nuclear and Non-Ionizing Energy-loss of Electrons with Low and Relativistic Energies in Materials and Space Environment  

E-Print Network (OSTI)

The treatment of the electron-nucleus interaction based on the Mott differential cross section was extended to account for effects due to screened Coulomb potentials, finite sizes and finite rest masses of nuclei for electrons above 200 keV and up to ultra high energies. This treatment allows one to determine both the total and differential cross sections, thus, subsequently to calculate the resulting nuclear and non-ionizing stopping powers. Above a few hundreds of MeV, neglecting the effect due to finite rest masses of recoil nuclei the stopping power and NIEL result to be largely underestimated; while, above a few tens of MeV the finite size of the nuclear target prevents a further large increase of stopping powers which approach almost constant values.

M. J. Boschini; C. Consolandi; M. Gervasi; S. Giani; D. Grandi; V. Ivanchenko; P. Nieminem; S. Pensotti; P. G. Rancoita; M. Tacconi

2011-12-06T23:59:59.000Z

396

Magnetic structure of Coronal Mass Ejections  

E-Print Network (OSTI)

We present several models of the magnetic structure of solar coronal mass ejections (CMEs). First, we model CMEs as expanding force-free magnetic structures. While keeping the internal magnetic field structure of the stationary solutions, expansion leads to complicated internal velocities and rotation, while the field structures remain force-free. Second, expansion of a CME can drive resistive dissipation within the CME changing the ionization states of different ions. We fit in situ measurements of ion charge states to the resistive spheromak solutions. Finally, we consider magnetic field structures of fully confined stable magnetic clouds containing both toroidal and poloidal magnetic fields and having no surface current sheets. Expansion of such clouds may lead to sudden onset of reconnection events.

Lyutikov, Maxim

2012-01-01T23:59:59.000Z

397

Dynamic modelling for thermal micro-actuators using thermal networks  

E-Print Network (OSTI)

Dynamic modelling for thermal micro-actuators using thermal networks Beatriz L´opez-Wallea,1 and analytical calculations. Key words: Micro-actuators, Thermal modelling, Electrical analogy, Thermal network 1 and MicroMechatronic Systems Department (AS2M), 24 rue Alain Savary, 25000 Besan¸con, France Abstract

Paris-Sud XI, Université de

398

A VUV photoionization measurement and ab-initio calculation of the ionization energy of gas phase SiO2  

SciTech Connect

In this work we report on the detection and vacuum-ultraviolet (VUV) photoionization of gas phase SiO2 generated in situ via laser ablation of silicon in a CO2 molecular beam. The resulting species are investigated by single photon ionization with tunable VUV synchrotron radiation and mass analyzed using reflectron mass spectrometry. Photoionization efficiency (PIE) curves are recorded for SiO and SiO2 and ionization energy estimates are revealed from such measurements. A state-to-state ionizationenergy of 12.60 (+-0.05) eV is recorded by fitting two prominent peaks in the PIE curve for the following process: 1SUM O-Si-O --> 2PRODg [O-Si-O]+. Electronic structure calculations aid in the interpretation of the photoionization process and allow for identification of the symmetric stretch of 2PRODg [O-Si-O]+ which is observed in the PIE spectrum to be 0.11 eV (890 cm-1) above the ground state of the cation and agrees with the 892 cm-1 symmetric stretch frequency calculated at the CCSD(T)/aug-cc-pVTZ level.

Kostko, Oleg; Ahmed, Musahid; Metz, Ricardo B.

2008-12-05T23:59:59.000Z

399

Elbow mass flow meter  

DOE Patents (OSTI)

Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

McFarland, Andrew R. (College Station, TX); Rodgers, John C. (Santa Fe, NM); Ortiz, Carlos A. (Bryan, TX); Nelson, David C. (Santa Fe, NM)

1994-01-01T23:59:59.000Z

400

Thermal efficiency of single-pass solar air collector  

SciTech Connect

Efficiency of a finned single-pass solar air collector was studied. This paper presents the experimental study to investigate the effect of solar radiation and mass flow rate on efficiency. The fins attached at the back of absorbing plate to improve the thermal efficiency of the system. The results show that the efficiency is increased proportional to solar radiation and mass flow rate. Efficiency of the collector archived steady state when reach to certain value or can be said the maximum performance.

Ibrahim, Zamry; Ibarahim, Zahari; Yatim, Baharudin [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan (Malaysia); Ruslan, Mohd Hafidz [Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan (Malaysia)

2013-11-27T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Propagation direction reversal of ionization zones in the transition between high and low current magnetron sputtering  

SciTech Connect

Past research has revealed the propagation of dense, asymmetric ionization zones in both high and low current magnetron discharges. Here we report about the direction reversal of ionization zone propagation as observed with fast cameras. At high currents, zones move in the E B direction with velocities of 103 to 104 m/s. However at lower currents, ionization zones are observed to move in the opposite, the -E B direction, with velocities ~;; 103 m/s. It is proposed that the direction reversal is associated with the local balance of ionization and supply of neutrals in the ionization zone.

School of Materials Science and Engineering, State Key Lab for Materials Processing and Die & Mold Technology, Huazhong University of Science and Technology, Wuhan 430074, China; Department of Physics, University of California Berkeley, Berkeley, California 94720, USA; Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA; Yang, Yuchen; Liu, Jason; Liu, Lin; Anders, André

2014-12-11T23:59:59.000Z

402

Low Dose Radiation Research Program: Research Highlights - Ionizing  

NLE Websites -- All DOE Office Websites (Extended Search)

Affects Cancer Frequency and Characteristics by Acting Affects Cancer Frequency and Characteristics by Acting on the Microenvironment Background: For more than a quarter century the scientific rationale for extrapolating radiation health effects has been underpinned by biophysical target theory. Fundamental to target theory is that the effect (e.g., DNA damage, mutation, cancer) is proportional to dose based on interaction of energy with biological targets, specifically DNA. However, the biology following ionizing radiation is more than just DNA damage, repair, or misrepair. Cellular responses to ionizing radiation can affect phenotype, cell interactions, lineage commitment, differentiation and genomic stability, all of which have been widely documented in cultured cells and many observed in vivo. This class of non-targeted effects induced

403

Low dose ionizing radiation induces tumor growth promoting factors in  

NLE Websites -- All DOE Office Websites (Extended Search)

ionizing radiation induces tumor growth promoting factors in ionizing radiation induces tumor growth promoting factors in stress-induced premature senescent fibroblasts David Boothman University of Texas Southwestern Medical Center at Dallas Abstract Recent evidence suggest that the causes of cancer development are not limited to mutations within cancer cells, but also involve in alterations of cancer microenvironment. Senescent cells are irreversibly growth arrested, but remain metabolically active. Senescent cells, especially senescent fibroblasts in the stroma may provide a beneficial environment for tumor growth through secretion of certain factors. Accumulation of senescent cells in the stroma of patients repeatedly exposed to low doses of IR or low dose rates of IR, could be an important factor, causing alteration of the microenvironment that ultimately benefits tumor

404

Ionic Liquids and Ionizing Radiation: Reactivity of Highly Energetic  

NLE Websites -- All DOE Office Websites (Extended Search)

Ionizing Radiation: Reactivity of Highly Energetic Ionizing Radiation: Reactivity of Highly Energetic Species James F. Wishart J. Phys. Chem. Lett. 1, 3225-3231 (2010). [Find paper at ACS Publications] or use ACS Articles on Request View the video on this Perspective article at The Journal of Physical Chemistry Letters (5:03) Selected for the ACS Special Virtual Issue on Ionic Liquids (March 2011). Abstract: Due to their unique properties, ionic liquids present many opportunities for basic research on the interactions of radiation with materials under conditions not previously available. At the same time, there are practical applied reasons for characterizing, understanding, and being able to predict how ionic-liquid-based devices and industrial-scale systems will perform under conditions of extreme reactivity, including radiation. This

405

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Globus Ruth NASA Ames Research Center Abstract Osteoporosis profoundly affects the aging U.S. population and exposure to high doses of radiation causes bone loss similar to age-related osteoporosis, although the influence of low dose radiation exposures is not known. The central hypothesis of our DOE project (NASA supplement) is that low doses of radiation modulate subsequent skeletal degeneration via oxidative pathways. Our working hypothesis is that a prior exposure to low dose radiation regulates oxidative metabolism within bone and contributes to bone loss caused either by subsequent high, challenge doses of radiation or by aging. HZE source: Because astronauts are exposed to radiation from GCR and solar

406

Detection of single atoms by resonance ionization spectroscopy  

SciTech Connect

Rutherford's idea for counting individual atoms can, in principle, be implemented for nearly any type of atom, whether stable or radioactive, by using methods of resonance ionization. With the RIS technique, a laser is tuned to a wavelength which will promote a valence electron in a Z-selected atom to an excited level. Additional resonance or nonresonance photoabsorption steps are used to achieve nearly 100% ionization efficiencies. Hence, the RIS process can be saturated for the Z-selected atoms; and since detectors are available for counting either single electrons or positive ions, one-atom detection is possible. Some examples are given of one-atom detection, including that of the noble gases, in order to show complementarity with AMS methods. For instance, the detection of /sup 81/Kr using RIS has interesting applications for solar neutrino research, ice-cap dating, and groundwater dating. 39 refs., 7 figs., 2 tabs.

Hurst, G.S.

1986-01-01T23:59:59.000Z

407

COSMIC RAY HEATING OF THE WARM IONIZED MEDIUM  

SciTech Connect

Observations of line ratios in the Milky Way's warm ionized medium suggest that photoionization is not the only heating mechanism present. For the additional heating to explain the discrepancy, it would have to have a weaker dependence on the gas density than the cooling rate, {Lambda}n{sub e}{sup 2}. Reynolds et al. suggested turbulent dissipation or magnetic field reconnection as possible heating sources. We investigate here the viability of MHD-wave mediated cosmic ray heating as a supplemental heating source. This heating rate depends on the gas density only through its linear dependence on the Alfven speed, which goes as n{sub e}{sup -1/2}. We show that, scaled to appropriate values of cosmic ray energy density, cosmic ray heating can be significant. Furthermore, this heating is stable to perturbations. These results should also apply to warm ionized gas in other galaxies.

Wiener, Joshua; Peng Oh, S. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States)] [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Zweibel, Ellen G. [Departments of Astronomy and Physics, and Center for Magnetic Self-Organization, University of Wisconsin-Madison, Madison, WI 53706 (United States)] [Departments of Astronomy and Physics, and Center for Magnetic Self-Organization, University of Wisconsin-Madison, Madison, WI 53706 (United States)

2013-04-10T23:59:59.000Z

408

Aerodynamic Effects in Weakly Ionized Gas: Phenomenology and Applications  

SciTech Connect

Aerodynamic effects in ionized gases, often neglected phenomena, have been subject of a renewed interest in recent years. After a brief historical account, we discuss a selected number of effects and unresolved problems that appear to be relevant in both aeronautic and propulsion applications in subsonic, supersonic, and hypersonic flow. Interaction between acoustic shock waves and weakly ionized gas is manifested either as plasma-induced shock wave dispersion and acceleration or as shock-wave induced double electric layer in the plasma, followed by the localized increase of the average electron energy and density, as well as enhancement of optical emission. We describe the phenomenology of these effects and discuss several experiments that still do not have an adequate interpretation. Critical for application of aerodynamic effects is the energy deposition into the flow. We classify and discuss some proposed wall-free generation schemes with respect to the efficiency of energy deposition and overall generation of the aerodynamic body force.

Popovic, S.; Vuskovic, L. [Department of Physics, Old Dominion University, Norfolk, Virginia (United States)

2006-12-01T23:59:59.000Z

409

Characterization of surface and layered films with cluster secondary ion mass spectrometry  

E-Print Network (OSTI)

chamber is made of stainless steel tube, with most of the surface area (80%) replaced with a 0.01-inch diameter tungsten wire grid. Another tungsten wire (electron ionization filament) is wrapped around the electrode with ~ 5 mm distance from... sparking between the high voltage components and the insulators, which ultimately leads to unstable performance of the ion source. The thermal electron emission tungsten filament deteriorates with usage as well. Signs of an aged filament include: high...

Li, Zhen

2008-10-10T23:59:59.000Z

410

Characterization of surface and layered films with cluster secondary ion mass spectrometry  

E-Print Network (OSTI)

chamber is made of stainless steel tube, with most of the surface area (80%) replaced with a 0.01-inch diameter tungsten wire grid. Another tungsten wire (electron ionization filament) is wrapped around the electrode with ~ 5 mm distance from... sparking between the high voltage components and the insulators, which ultimately leads to unstable performance of the ion source. The thermal electron emission tungsten filament deteriorates with usage as well. Signs of an aged filament include: high...

Li, Zhen

2009-05-15T23:59:59.000Z

411

Observation of ionization fronts in low density foam targets  

SciTech Connect

Ionization fronts have been observed in low density chlorinated foam targets and low density foams confined in gold tubes using time resolved {ital K}-shell absorption spectroscopy. The front was driven by an intense pulse of soft x-rays produced by high power laser irradiation. The density and temperature profiles inferred from the radiographs provided detailed measurement of the conditions. The experimental data were compared to radiation hydrodynamics simulations and reasonable agreement was obtained. {copyright} {ital 1999 American Institute of Physics.}

Hoarty, D. [Imperial College of Science, Technology and Medicine, London (United Kingdom)] [Imperial College of Science, Technology and Medicine, London (United Kingdom); [Radiation Physics Department, AWE Aldermaston, Reading, Berkshire (United Kingdom); Willi, O.; Barringer, L.; Vickers, C. [Imperial College of Science, Technology and Medicine, London (United Kingdom)] [Imperial College of Science, Technology and Medicine, London (United Kingdom); Watt, R. [P24, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [P24, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Nazarov, W. [Chemistry Department, University of Dundee (United Kingdom)] [Chemistry Department, University of Dundee (United Kingdom)

1999-05-01T23:59:59.000Z

412

Interference in above-threshold-ionization electron distributions from molecules  

SciTech Connect

We present quantum-mechanical studies on above-threshold ionization of molecular ions in two and three dimensions. The momentum distributions show signatures of interfering emissions from the molecular centers. These structures deviate from a simple double-slit model that ignores the electron-ion interaction, but they are reproduced by an eikonal model. Such distortions of the interference pattern are partly responsible for the absence of clear interference patterns in the angle-integrated electron energy spectra.

Henkel, Jost [Institut fuer Physikalische und Theoretische Chemie, Universitaet Wuerzburg, and Roentgen Research Center for Complex Material Systems, Am Hubland, D-97074 Wuerzburg (Germany); Institut fuer Theoretische Physik and Centre for Quantum Engineering and Space-Time Research (QUEST), Leibniz Universitaet Hannover Appelstrasse 2, D-30167 Hannover (Germany); Lein, Manfred [Institut fuer Theoretische Physik and Centre for Quantum Engineering and Space-Time Research (QUEST), Leibniz Universitaet Hannover Appelstrasse 2, D-30167 Hannover (Germany); Engel, Volker [Institut fuer Physikalische und Theoretische Chemie, Universitaet Wuerzburg, and Roentgen Research Center for Complex Material Systems, Am Hubland, D-97074 Wuerzburg (Germany)

2011-05-15T23:59:59.000Z

413

Ionization and equation of state of dense xenon at high pressures and high temperatures  

Science Journals Connector (OSTI)

The ionization degree and equation of state of dense xenon plasma were calculated by using self-consistent fluid variational theory for temperature of 4–30kK and density of 0.01–8.5g?cm3. The dense fluid xenon will be ionized at high pressures and temperatures. The ionization energy of xenon will be lowered due to the interactions among all particles of Xe, Xe+, Xe2+, and e. The ionization degree is obtained from nonideal ionization equilibrium, taking into account the correlative contributions to the chemical potential which is determined self-consistently by the free energy function. The composition of xenon has been calculated with given densities and temperatures in the region of partial ionization. The calculated results show a pressure softening regime at the onset of ionization. Comparison is performed with available shock-wave experiments and other theoretical calculations.

Q. F. Chen, L. C. Cai, Y. J. Gu, and Y. Gu

2009-01-22T23:59:59.000Z

414

Self-consistent chemical model of partially ionized plasmas  

Science Journals Connector (OSTI)

A simple renormalization theory of plasma particle interactions is proposed. It primarily stems from generic properties of equilibrium distribution functions and allows one to obtain the so-called generalized Poisson-Boltzmann equation for an effective interaction potential of two chosen particles in the presence of a third one. The same equation is then strictly derived from the Bogolyubov-Born-Green-Kirkwood-Yvon (BBGKY) hierarchy for equilibrium distribution functions in the pair correlation approximation. This enables one to construct a self-consistent chemical model of partially ionized plasmas, correctly accounting for the close interrelation of charged and neutral components thereof. Minimization of the system free energy provides ionization equilibrium and, thus, permits one to study the plasma composition in a wide range of its parameters. Unlike standard chemical models, the proposed one allows one to study the system correlation functions and thereby to obtain an equation of state which agrees well with exact results of quantum-mechanical activity expansions. It is shown that the plasma and neutral components are strongly interrelated, which results in the short-range order formation in the corresponding subsystem. The mathematical form of the results obtained enables one to both firmly establish this fact and to determine a characteristic length of the structure formation. Since the cornerstone of the proposed self-consistent chemical model of partially ionized plasmas is an effective pairwise interaction potential, it immediately provides quite an efficient calculation scheme not only for thermodynamical functions but for transport coefficients as well.

Yu. V. Arkhipov, F. B. Baimbetov, and A. E. Davletov

2011-01-21T23:59:59.000Z

415

Ionized gas at the edge of the Central Molecular Zone  

E-Print Network (OSTI)

To determine the properties of the ionized gas at the edge of the CMZ near Sgr E we observed a small portion of the edge of the CMZ near Sgr E with spectrally resolved [C II] 158 micron and [N II] 205 micron fine structure lines at six positions with the GREAT instrument on SOFIA and in [C II] using Herschel HIFI on-the-fly strip maps. We use the [N II] spectra along with a radiative transfer model to calculate the electron density of the gas and the [C II] maps to illuminate the morphology of the ionized gas and model the column density of CO-dark H2. We detect two [C II] and [N II] velocity components, one along the line of sight to a CO molecular cloud at -207 km/s associated with Sgr E and the other at -174 km/s outside the edge of another CO cloud. From the [N II] emission we find that the average electron density is in the range of about 5 to 25 cm{-3} for these features. This electron density is much higher than that of the warm ionized medium in the disk. The column density of the CO-dark H$_2$ layer ...

Langer, W D; Pineda, J L; Velusamy, T; Requena-Torres, M A; Wiesemeyer, H

2015-01-01T23:59:59.000Z

416

Electron-impact ionization cross section of rubidium  

Science Journals Connector (OSTI)

A theoretical model for electron-impact ionization cross section has been applied to Rb and the theoretical cross section (from the threshold to 1 keV in incident energy) is in good agreement with the recent experimental data obtained using Rb atoms trapped in a magneto-optical trap. The theoretical model, called the binary-encounter–dipole (BED) model, combines a modified Mott cross section with the high-energy behavior of Born cross sections. To obtain the continuum dipole oscillator strength df/dE of the 5s electron required in the BED model, we used Dirac-Fock continuum wave functions with a core polarization potential that reproduced the known position of the Cooper minimum in the photoionization cross section. For inner-shell ionization, we used a simpler version of df/dE, which retained the hydrogenic shape. The contributions of the 4p?4d, 5s, and 5p autoionizing excitations were estimated using the plane-wave Born approximation. As a by-product, we also present the dipole oscillator strengths for the 5s?np1/2 and 5s?np3/2 transitions for high principal quantum numbers n near the ionization threshold obtained from the Dirac-Fock wave functions with the same core polarization potential as that used for the continuum wave functions.

Yong-Ki Kim; Jacek Migda?ek; Wojciech Siegel; Jacek Biero?

1998-01-01T23:59:59.000Z

417

Thermal-Hydrologic-Mechanical Study of Pre-Closure Off-Normal Thermal Scenarios at the Proposed Yucca Mountain Nuclear Waste Repository  

SciTech Connect

The proposed nuclear waste repository at Yucca Mountain, Nevada currently includes a minimum of 50 years forced ventilation inside of emplacement drifts prior to repository closure. To regulate the heat generated from emplaced waste packages, the ventilation during the pre-closure period should be continuous. Off-normal thermal scenarios that consider temporary shutdown of the pre-closure ventilation are investigated to determine the impacts of ventilation shutdown on the thermal-hydrologic-mechanical behaviors of the emplacement drifts. In-drift heat transfer processes including radiation, convection, and conduction are studied. The analysis provides a ventilation heat removal ratio that varies on the drift location and the ventilation duration. The heat removal ratio is transferred and utilized in the NUFT thermal-hydrology software. The NUFT software is used to investigate the thermal-hydrologic impacts on the repository rock mass for the off-normal thermal scenarios with various shutdown durations at various pre-closure times. The predicted rock mass temperature evaluated from the thermal-hydrologic analysis is applied for the thermal-mechanical analysis of the off-normal thermal scenarios. The results show that degradation and rockfall of the emplacement drifts due to the off-normal thermal scenarios will be minimal, and it is concluded that the impacts of off-normal thermal scenarios on the stability of the emplacement drifts will be insignificant.

J. Leem; M. Lin; Y. Sun; D. Kicker

2005-03-09T23:59:59.000Z

418

The Bulk Channel in Thermal Gauge Theories  

E-Print Network (OSTI)

We investigate the thermal correlator of the trace of the energy-momentum tensor in the SU(3) Yang-Mills theory. Our goal is to constrain the spectral function in that channel, whose low-frequency part determines the bulk viscosity. We focus on the thermal modification of the spectral function, $\\rho(\\omega,T)-\\rho(\\omega,0)$. Using the operator-product expansion we give the high-frequency behavior of this difference in terms of thermodynamic potentials. We take into account the presence of an exact delta function located at the origin, which had been missed in previous analyses. We then combine the bulk sum rule and a Monte-Carlo evaluation of the Euclidean correlator to determine the intervals of frequency where the spectral density is enhanced or depleted by thermal effects. We find evidence that the thermal spectral density is non-zero for frequencies below the scalar glueball mass $m$ and is significantly depleted for $m\\lesssim\\omega\\lesssim 3m$.

Harvey B. Meyer

2010-02-17T23:59:59.000Z

419

Direct Observations of the Ionizing Star in the UC HII Region G29.96-0.02: A Strong Constraint on the Stellar Birth Line for Massive Stars  

E-Print Network (OSTI)

We have observed the ultracompact HII region G29.96-0.02 in the near infrared J, H, and K bands and in the Br-gamma line. By comparison with radio observations, we determine that the extinction to the nebula is AK = 2.14 with a 3 sigma uncertainty of 0.25. We identify the ionizing star and determine its intrinsic K magnitude. The star does not have an infrared excess and so appears to be no longer accreting. The K magnitude and the bolometric luminosity allow us to place limits on the location of the ionizing star in the HR diagram. The 3 sigma upper limit on the effective temperature of the ionizing star is 42500 K. We favor a luminosity appropriate for star with a mass in excess of about 60 solar masses. The limit on the temperature and luminosity exclude stars on the ZAMS and stars within 10^6 yr of the ZAMS. Since the age of the UC HII region is estimated to be only about 10^5 yr, we suggest that this is direct evidence that the stellar birth line for massive stars at twice solar metallicity must be significantly redder than the ZAMS.

Alan M. Watson; Alison L. Coil; Debra S. Shepherd; Peter Hofner; Ed Churchwell

1997-05-01T23:59:59.000Z

420

THERMAL NEUTRON BACKSCATTER IMAGING.  

SciTech Connect

Objects of various shapes, with some appreciable hydrogen content, were exposed to fast neutrons from a pulsed D-T generator, resulting in a partially-moderated spectrum of backscattered neutrons. The thermal component of the backscatter was used to form images of the objects by means of a coded aperture thermal neutron imaging system. Timing signals from the neutron generator were used to gate the detection system so as to record only events consistent with thermal neutrons traveling the distance between the target and the detector. It was shown that this time-of-flight method provided a significant improvement in image contrast compared to counting all events detected by the position-sensitive {sup 3}He proportional chamber used in the imager. The technique may have application in the detection and shape-determination of land mines, particularly non-metallic types.

VANIER,P.; FORMAN,L.; HUNTER,S.; HARRIS,E.; SMITH,G.

2004-10-16T23:59:59.000Z

Note: This page contains sample records for the topic "thermal ionization mass" 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

Thermal neutron capture gamma-rays  

SciTech Connect

The energy and intensity of gamma rays as seen in thermal neutron capture are presented. Only those (n,..cap alpha..), E = thermal, reactions for which the residual nucleus mass number is greater than or equal to 45 are included. These correspond to evaluations published in Nuclear Data Sheets. The publication source data are contained in the Evaluated Nuclear Structure Data File (ENSDF). The data presented here do not involve any additional evaluation. Appendix I lists all the residual nuclides for which the data are included here. Appendix II gives a cumulated index to A-chain evaluations including the year of publication. The capture gamma ray data are given in two tables - the Table 1 is the list of all gamma rays seen in (n,..gamma..) reaction given in the order of increasing energy; the Table II lists the gamma rays according to the nuclide.

Tuli, J.K.

1983-01-01T23:59:59.000Z

422

Thermal ignition combustion system  

DOE Patents (OSTI)

The thermal ignition combustion system comprises means for providing walls defining an ignition chamber, the walls being made of a material having a thermal conductivity greater than 20 W/m C and a specific heat greater than 480 J/kg C with the ignition chamber being in constant communication with the main combustion chamber, means for maintaining the temperature of the walls above a threshold temperature capable of causing ignition of a fuel, and means for conducting fuel to the ignition chamber. 8 figs.

Kamo, R.; Kakwani, R.M.; Valdmanis, E.; Woods, M.E.

1988-04-19T23:59:59.000Z

423

Scattering Solar Thermal Concentrators  

Energy.gov (U.S. Department of Energy (DOE))

"This fact sheet describes a scattering solar thermal concentrators project awarded under the DOE's 2012 SunShot Concentrating Solar Power R&D award program. The team, led by the Pennsylvania State University, is working to demonstrate a new, scattering-based approach to concentrating sunlight that aims to improve the overall performance and reliability of the collector field. The research team aims to show that scattering solar thermal collectors are capable of achieving optical performance equal to state-of-the-art parabolic trough systems, but with the added benefits of immunity to wind-load tracking error, more efficient land use, and utilization of stationary receivers."

424

Thermal ignition combustion system  

SciTech Connect

The thermal ignition combustion system comprises means for providing walls defining an ignition chamber, the walls being made of a material having a thermal conductivity greater than 20 W/m.degree. C. and a specific heat greater than 480 J/kg.degree. C. with the ignition chamber being in constant communication with the main combustion chamber, means for maintaining the temperature of the walls above a threshold temperature capable of causing ignition of a fuel, and means for conducting fuel to the ignition chamber.

Kamo, Roy (Columbus, IN); Kakwani, Ramesh M. (Columbus, IN); Valdmanis, Edgars (Columbus, IN); Woods, Melvins E. (Columbus, IN)

1988-01-01T23:59:59.000Z

425

Thermal ignition combustion system  

SciTech Connect

A thermal ignition combustion system adapted for use with an internal combustion engine is described comprising: (a) means for providing ignition chamber walls defining an ignition chamber, the chamber walls being made of a material having a thermal conductivity greater than 20 W/m/sup 0/C. and a specific heat greater than 480J/kg/sup 0/C., the ignition chamber being in constant communication with the main combustion chamber; (b) means for maintaining the temperature of the chamber walls above a threshold temperature capable of causing ignition of a fuel; and (c) means for conducting fuel to the ignition chamber.

Kamo, R.; Kakwani, R.M.; Valdmanis, E.; Woods, M.E.

1988-04-19T23:59:59.000Z

426

Thermal test options  

SciTech Connect

Shipping containers for radioactive materials must be qualified to meet a thermal accident environment specified in regulations, such at Title 10, Code of Federal Regulations, Part 71. Aimed primarily at the shipping container design, this report discusses the thermal testing options available for meeting the regulatory requirements, and states the advantages and disadvantages of each approach. The principal options considered are testing with radiant heat, furnaces, and open pool fires. The report also identifies some of the facilities available and current contacts. Finally, the report makes some recommendations on the appropriate use of these different testing methods.

Koski, J.A.; Keltner, N.R.; Sobolik, K.B.

1993-02-01T23:59:59.000Z

427

The effect of intergalactic helium on hydrogen reionization: implications for the sources of ionizing photons at z>6  

Science Journals Connector (OSTI)

......model the effect of hydrogen and helium ionizing...for modelling the production of ionizing photons...the total comoving hydrogen ionizing emissivity...ionizing photon production increases toward...because almost all the methods used to derive are...patches of neutral hydrogen may still lurk undetected......

B. Ciardi; J. S. Bolton; A. Maselli; L. Graziani

2012-06-11T23:59:59.000Z

428

Composition of a thermal plasma formed from PTFE with copper in non-oxidant atmosphere.  

E-Print Network (OSTI)

1 Composition of a thermal plasma formed from PTFE with copper in non-oxidant atmosphere. Part I the minimization of given thermodynamic functions or mass action laws even with plasmas out of thermal equilibrium- . Key Words: circuit breakers, SF6, PTFE, carbon formation, copper, dielectric gas, plasma composition

Paris-Sud XI, Université de

429

Heat and mass transfer in rotating fluid with Hall current, II  

Science Journals Connector (OSTI)

Effects of Hall current on the hydromagnetic free-convection resulting from the combined effects of thermal and mass diffusion of an electrically conducting liquid past an infinite vertical porous plate in a r...

H. L. Agrawal; P. C. Ram; V. Singh

430

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network (OSTI)

ENERGY STORAGE FOR CONCENTRATING SOLAR POWER PLANTS,”Thermal Energy Storage in Concentrated Solar Thermal PowerThermal Energy Storage in Concentrated Solar Thermal Power

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

431

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network (OSTI)

CHANGE THERMAL ENERGY STORAGE FOR CONCENTRATING SOLAR POWERfor Thermal Energy Storage in Concentrated Solar Thermalfor Thermal Energy Storage in Concentrated Solar Thermal

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

432

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network (OSTI)

and Background Solar thermal energy collection is anCHANGE THERMAL ENERGY STORAGE FOR CONCENTRATING SOLAR POWERfor Thermal Energy Storage in Concentrated Solar Thermal

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

433

Nuclear Masses in Astrophysics  

E-Print Network (OSTI)

Among all nuclear ground-state properties, atomic masses are highly specific for each particular combination of N and Z and the data obtained apply to a variety of physics topics. One of the most crucial questions to be addressed in mass spectrometry of unstable radionuclides is the one of understanding the processes of element formation in the Universe. To this end, accurate atomic mass values of a large number of exotic nuclei participating in nucleosynthesis are among the key input data in large-scale reaction network calculations. In this paper, a review on the latest achievements in mass spectrometry for nuclear astrophysics is given.

Christine Weber; Klaus Blaum; Hendrik Schatz

2008-12-09T23:59:59.000Z

434

EMSL - Mass Spectrometer  

NLE Websites -- All DOE Office Websites (Extended Search)

mass-spectrometer en Physical Properties of Ambient and Laboratory-Generated Secondary Organic Aerosol. http:www.emsl.pnl.govemslwebpublicationsphysical-properties-ambient-and...

435

Rugged miniaturized mass sensors for use in plutonium conversion processes  

SciTech Connect

Ionization is produced either through Plasma Desorption, in the case of a solid, using fission fragments from a Cf-252 source; or in the case of a gas, via an electron avalanche from the impact on a microsphere detector of {alpha} particles from a radioactive source. The gaseous compound analysis yielded multiple peaks on parent ion and molecular fragments. In the solid compound analysis, the results indicated that solid-state mass spectrometry will provide important information about the degradation of materials by measured changes in molecular weight.

Schweikert, E.A.; James, W.D. [Texas A and M Univ., College Station, TX (United States). Center for Chemical Characterization and Analysis

1999-05-01T23:59:59.000Z

436

Dissociative-ionization cross sections for 12-keV-electron impact on CO{sub 2}  

SciTech Connect

The dissociative ionization of a CO{sub 2} molecule is studied at an electron energy of 12 keV using the multiple ion coincidence imaging technique. The absolute partial ionization cross sections and the precursor-specific absolute partial ionization cross sections of resulting fragment ions are obtained and reported. It is found that {approx}75% of single ionization, 22% of double ionization, and {approx}2% of triple ionization of the parent molecule contribute to the total fragment ion yield; quadruple ionization of CO{sub 2} is found to make a negligibly small contribution. Furthermore, the absolute partial ionization cross sections for ion-pair and ion-triple formation are measured for nine dissociative ionization channels of up to a quadruply ionized CO{sub 2} molecule. In addition, the branching ratios for single-ion, ion-pair, and ion-triple formation are also determined.

Bhatt, Pragya; Singh, Raj; Yadav, Namita; Shanker, R. [Atomic Physics Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221005 (India)

2011-10-15T23:59:59.000Z

437

Thermal barrier coating  

DOE Patents (OSTI)

A thermal barrier coating for hot gas path components of a combustion turbine based on a zirconia-scandia system. A layer of zirconium scandate having the hexagonal Zr.sub.3 Sc.sub.4 O.sub.12 structure is formed directly on a superalloy substrate or on a bond coat formed on the substrate.

Bowker, Jeffrey Charles (Gibsonia, PA); Sabol, Stephen M. (Orlando, FL); Goedjen, John G. (Oviedo, FL)

2001-01-01T23:59:59.000Z

438

Thermal management of nanoelectronics  

E-Print Network (OSTI)

-state thermoelectric on- spot cooling, requiring efficient thermoelectric materials that can be integrated with the IC are further complicated by the fact that the material's ability to conduct heat deteriorates when at the packaging level but also at the nanoscale materials and device levels. THERMAL CHALLENGES AT NANOSCALE One

439

Thermal Reactor Safety  

SciTech Connect

Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

Not Available

1980-06-01T23:59:59.000Z

440

High-Temperature Thermal Array for Next Generation Solar Thermal...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3 Q1 High-Temperature Thermal Array for Next Generation Solar Thermal Power Production - FY13 Q1 This document summarizes the progress of this Los Alamos National Laboratory...

Note: This page contains sample records for the topic "thermal ionization mass" 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

Impact of Ageing on Thermal Efficiency of Solar Thermal Collectors  

Science Journals Connector (OSTI)

Today it is common practice to calculate the performance of solar thermal systems or solar collectors based on the results of a thermal performance test carried out with a new solar collector. However, for an int...

Elke Streicher; Stephan Fischer…

2009-01-01T23:59:59.000Z

442

Comparison of NTIMS and ICP-OES methods for the determination of boron concentrations in natural fresh and saline waters  

Science Journals Connector (OSTI)

Determination of B concentrations in natural fresh and ... the NTIMS (Negative Thermal Ionization Mass Spectrometry) isotope dilution technique which is virtually unaffected by such effects. NTIMS isotope diluti...

S. Barth

1997-07-01T23:59:59.000Z

443

Preliminary requirements for thermal storage subsystems in solar thermal applications  

SciTech Connect

Methodologies for the analysis of value and comparing thermal storage concepts are presented. Value is a measure of worth and is determined by the cost of conventional fuel systems. Value data for thermal storage in large solar thermal electric power applications are presented. Thermal storage concepts must be compared when all are performing the same mission. A method for doing that analysis, called the ranking index, is derived. Necessary data to use the methodology are included.

Copeland, R.J.

1980-04-01T23:59:59.000Z

444

Thermal Energy Storage (TES): Past, Present and Future  

NLE Websites -- All DOE Office Websites (Extended Search)

Thermal Energy Storage (TES): Past, Present and Future Thermal Energy Storage (TES): Past, Present and Future Speaker(s): Klaus Schiess Date: June 10, 2011 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Sila Kiliccote Thermal Energy Storage (TES) is a technology that stores "cooling" energy in a thermal storage mass. In the eighties and early nineties the utilities in California incentivised this technology to shift electrical on-peak power to off-peak. Thereafter, for various reasons TES became the most neglected permanent load shifting opportunity. It is only now with the challenges that the renewables provide that TES may have a come- back because it is basically the best and most economical AC battery available with a round trip efficiency of 100% or even better. This presentation gives some background to this development and shows the interdependence of

445

A Comparison of Different Methods of Ionizing GC Effluents  

Science Journals Connector (OSTI)

......energy is the catalytic and thermal energy of a hot, solid...appropriate electrical insulation at high temperatures. This electrical insulation requirement is one of...com parable performance specifications. The most common FID......

P.L. Patterson

1986-11-01T23:59:59.000Z

446

Elbow mass flow meter  

DOE Patents (OSTI)

The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity. 3 figs.

McFarland, A.R.; Rodgers, J.C.; Ortiz, C.A.; Nelson, D.C.

1994-08-16T23:59:59.000Z

447

The Origins of Mass  

SciTech Connect

The Higgs boson was discovered in July of 2012 and is generally understood to be the origin of mass. While those statements are true, they are incomplete. It turns out that the Higgs boson is responsible for only about 2% of the mass of ordinary matter. In this dramatic new video, Dr. Don Lincoln of Fermilab tells us the rest of the story.

Lincoln, Don

2014-07-30T23:59:59.000Z

448

Gas Chromatography -Mass Spectrometry  

E-Print Network (OSTI)

GCMS - 1 Gas Chromatography - Mass Spectrometry GC-MS ANALYSIS OF ETHANOL AND BENZENE IN GASOLINE Last updated: June 17, 2014 #12;GCMS - 2 Gas Chromatography - Mass Spectrometry GC-MS ANALYSIS). The goal of this experiment is to separate the components in a sample of gasoline using Gas Chromatography

Nizkorodov, Sergey

449

W Transverse Mass  

NLE Websites -- All DOE Office Websites (Extended Search)

Some Data Analysis Some Data Analysis The Tevatron produces millions of collisions each second in CDF and DZero. The detectors have hardware triggers to decide if a collision is "interesting," that is it contains a candidate event for any one of a number studies. Our dataset contains 48,844 candidate events for a W mass study. There are other datasets to study Z mass, top and b quarks, QCD, etc. Why don't all the W decays give exactly the same mass? Are all these candidates really Ws? What if we chose only some of these data. How would our choice effect the value of the transverse mass? Work with your classmates. Test the data to see what you can learn. Help with data analysis. Record the best estimate of the W transverse mass from your data analysis. Explain which data you used and why. Check with your classmates and explain any differences between your estimate and theirs.

450

Laboratory Study of Hall Reconnection in Partially Ionized Plasmas  

SciTech Connect

The effects of partial ionization (ni/nn ? 1%) on magnetic reconnection in the Hall regime have been studied systematically in the Magnetic Reconnection Experiment (MRX). It is shown that, when neutrals are added the Hall quadrupole field pattern and thus electron flow is unchanged while the ion outflow speed is reduced due to ion-neutral drag. However, in constrast to theoretical predictions, the ion diffusion layer width does not change appreciably. Therefore, the total ion outflow flux and the normalized reconnection rate are reduced.

Eric E. Lawrence, Hanto Ji, Masaaki Yamaada and Jongsoo Yoo

2012-05-15T23:59:59.000Z

451

Photo-ionization and residual electron effects in guided streamers  

SciTech Connect

Complementary experiments and numerical modeling reveal the important role of photo-ionization in the guided streamer propagation in helium-air gas mixtures. It is shown that the minimum electron concentration ?10{sup 8?}cm{sup ?3} is required for the regular, repeated propagation of the plasma bullets, while the streamers propagate in the stochastic mode below this threshold. The stochastic-to-regular mode transition is related to the higher background electron density in front of the propagating streamers. These findings help improving control of guided streamer propagation in applications from health care to nanotechnology and improve understanding of generic pre-breakdown phenomena.

Wu, S.; Lu, X., E-mail: luxinpei@hotmail.com; Liu, D.; Yang, Y.; Pan, Y. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Ostrikov, K. [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, QLD 4000 (Australia); Commonwealth Scientific and Industrial Research Organization, P. O. Box 218, Lindfield, NSW 2070 (Australia); School of Physics, The University of Sydney, Sydney NSW 2006 (Australia)

2014-10-15T23:59:59.000Z

452

Depolarizing collisions with hydrogen: neutral and singly ionized alkaline earths  

E-Print Network (OSTI)

Depolarizing collisions are elastic or quasielastic collisions that equalize the populations and destroy the coherence between the magnetic sublevels of atomic levels. In astrophysical plasmas, the main depolarizing collider is neutral hydrogen. We consider depolarizing rates on the lowest levels of neutral and singly ionized alkaly-earths Mg I, Sr I, Ba I, Mg II, Ca II, and Ba II, due to collisions with H. We compute ab initio potential curves of the atom-H system and solve the quantum mechanical dynamics. From the scattering amplitudes we calculate the depolarizing rates for Maxwellian distributions of colliders at temperatures T atmosphere, and their effect on Hanle effect diagnostics of solar magnetic fields.

Sainz, Rafael Manso; Sanz-Sanz, Cristina; Aguado, Alfredo; Ramos, Andres Asensio; Bueno, Javier Trujillo

2014-01-01T23:59:59.000Z

453

Plasma-assisted catalytic ionization using porous nickel plate  

SciTech Connect

Hydrogen atomic pair ions, i.e., H{sup +} and H{sup -} ions, are produced by plasma-assisted catalytic ionization using a porous nickel plate. Positive ions in a hydrogen plasma generated by dc arc discharge are irradiated to the porous plate, and pair ions are produced from the back of the irradiation plane. It becomes clear that the production quantity of pair ions mainly depends on the irradiation current of positive ions and the irradiation energy affects the production efficiency of H{sup -} ions.

Oohara, W.; Maeda, T.; Higuchi, T. [Department of Electronic Device Engineering, Yamaguchi University, Ube 755-8611 (Japan)

2011-09-15T23:59:59.000Z

454

Photo-Ionization of Lithium: A Many-Body Calculation  

Science Journals Connector (OSTI)

The photo-ionization cross section a? of lithium has been calculated to second order in Brueckner-Goldstone perturbation theory with Hartree-Fock as zero order, for ejected electron energies in the range 0<~k2<~0. 36 Ry. Other Hartree-Fock calculations of a? are analyzed using certain new theorems relating alternative forms of the matrix element. The final second-order perturbed values of a? in the length and velocity formulations are in good agreement with experiment throughout the energy range studied.

Edward S. Chang and M. R. C. McDowell

1968-12-05T23:59:59.000Z

455

Stability of negative ionization fronts: Regularization by electric screening?  

Science Journals Connector (OSTI)

We recently have proposed that a reduced interfacial model for streamer propagation is able to explain spontaneous branching. Such models require regularization. In the present paper we investigate how transversal Fourier modes of a planar ionization front are regularized by the electric screening length. For a fixed value of the electric field ahead of the front we calculate the dispersion relation numerically. These results guide the derivation of analytical asymptotes for arbitrary fields: for small wave-vector k, the growth rate s(k) grows linearly with k, for large k, it saturates at some positive plateau value. We give a physical interpretation of these results.

Manuel Arrayás and Ute Ebert

2004-03-31T23:59:59.000Z

456

Optical remote diagnostics of atmospheric propagating beams of ionizing radiation  

DOE Patents (OSTI)

Data is obtained for use in diagnosing the characteristics of a beam of ionizing radiation, such as charged particle beams, neutral particle beams, and gamma ray beams. In one embodiment the beam is emitted through the atmosphere and produces nitrogen fluorescence during passage through air. The nitrogen fluorescence is detected along the beam path to provide an intensity from which various beam characteristics can be calculated from known tabulations. Optical detecting equipment is preferably located orthogonal to the beam path at a distance effective to include the entire beam path in the equipment field of view.

Karl, Jr., Robert R. (Los Alamos, NM)

1990-01-01T23:59:59.000Z

457

Breakdown of the Dipole Approximation in Strong-Field Ionization  

E-Print Network (OSTI)

We report the breakdown of the electric dipole approximation in the long-wavelength limit in strong-field ionization with linearly polarized few-cycle mid-infrared laser pulses at intensities on the order of 10$^{13}$ W/cm$^2$. Photoelectron momentum distributions were recorded by velocity map imaging and projected onto the beam propagation axis. We observe an increasing shift of the peak of this projection opposite to the beam propagation direction with increasing laser intensities. From a comparison with semi-classical simulations, we identify the combined action of the magnetic field of the laser pulse and the Coulomb potential as origin of our observations.

Ludwig, A; Mayer, B W; Phillips, C R; Gallmann, L; Keller, U

2014-01-01T23:59:59.000Z

458

Breakdown of the Dipole Approximation in Strong-Field Ionization  

E-Print Network (OSTI)

We report the breakdown of the electric dipole approximation in the long-wavelength limit in strong-field ionization with linearly polarized few-cycle mid-infrared laser pulses at intensities on the order of 10$^{13}$ W/cm$^2$. Photoelectron momentum distributions were recorded by velocity map imaging and projected onto the beam propagation axis. We observe an increasing shift of the peak of this projection opposite to the beam propagation direction with increasing laser intensities. From a comparison with semi-classical simulations, we identify the combined action of the magnetic field of the laser pulse and the Coulomb potential as origin of our observations.

A. Ludwig; J. Maurer; B. W. Mayer; C. R. Phillips; L. Gallmann; U. Keller

2014-08-11T23:59:59.000Z

459

Thermal Storage of Solar Energy  

Science Journals Connector (OSTI)

Thermal storage is needed to improve the efficiency and usefulness of solar thermal systems. The paper indicates the main storage ... which would greatly increase the practical use of solar energy — is more diffi...

H. Tabor

1984-01-01T23:59:59.000Z

460

Interactive visual intervention planning in particle accelerator environments with ionizing radiation  

E-Print Network (OSTI)

Radiation is omnipresent. It has many interesting applications: in medicine, where it allows curing and diagnosing patients; in communication, where modern communication systems make use of electromagnetic radiation; and in science, where it is used to discover the structure of materials; to name a few. Physically, radiation is a process in which particles or waves travel through any kind of material, usually air. Radiation can be very energetic, in which case it can break the atoms of ordinary matter (ionization). If this is the case, radiation is called ionizing. It is known that ionizing radiation can be far more harmful to living beings than non-ionizing radiation. In this dissertation, we are concerned with ionizing radiation. Naturally occurring ionizing radiation in the form of radioactivity is a most natural phenomenon. Almost everything is radioactive: there is radiation emerging from the soil, it is in the air, and the whole planet is constantly undergoing streams of energetic cosmic radiation. Sinc...

Fabry, Thomas

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461

The Influence of Chemi-ionization and Recombination Processes on Spectral Line Shapes in Stellar Atmospheres  

E-Print Network (OSTI)

In this work, the chemi-ionization processes in atom- Rydberg atom collisions, as well as the corresponding chemi-recombination processes are considered as factors of influence on the atom exited-state populations in weakly ionized layers of stellar atmospheres. The presented results are related to the photospheres of the Sun and some M red dwarfs as well as weakly ionized layers of DB white dwarfs atmospheres. It has been found that the mentioned chemi ionization/recombination processes dominate over the relevant concurrent electron-atom and electron-ion ionization and recombination process in all parts of considered stellar atmospheres. The obtained results demonstrate the fact that the considered chemi ionization/recombination processes must have a very significant influence on the optical properties of the stellar atmospheres. Thus, it is shown that these processes and their importance for non-local thermodynamic equilibrium (non-LTE) modeling of the solar atmospheres should be investigated further.

Mihajlov, Anatolij A; Sreckovic, Vladimir A; Dimitrijevic, Milan S

2011-01-01T23:59:59.000Z

462

THERMAL ENERGY STORAGE IN AQUIFERS WORKSHOP  

E-Print Network (OSTI)

Survey of Thermal Energy Storage in Aquifers Coupled withLow Temperature Thermal Energy Storage Program of Oak Ridgefor Seasonal Thermal Energy Storage: An Overview of the DOE-

Authors, Various

2011-01-01T23:59:59.000Z

463

Electric Motor Thermal Management | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Merit Review and Peer Evaluation ape030bennion2011o.pdf More Documents & Publications Motor Thermal Control Electric Motor Thermal Management Electric Motor Thermal Management...

464

Power Electronic Thermal System Performance and Integration ...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

More Documents & Publications Motor Thermal Control Thermal Stress and Reliability for Advanced Power Electronics and Electric Machines Integrated Vehicle Thermal Management...

465

THERMAL ENERGY STORAGE IN AQUIFERS WORKSHOP  

E-Print Network (OSTI)

Scale Thermal Energy Storage for Cogeneration and Solarsolar captors, thermal effluents, low cost energy duringSeale Thermal Energy Storage for Cogeneration and Solar

Authors, Various

2011-01-01T23:59:59.000Z

466

Ocean Thermal Extractable Energy Visualization: Final Technical...  

Office of Environmental Management (EM)

Ocean Thermal Extractable Energy Visualization: Final Technical Report Ocean Thermal Extractable Energy Visualization: Final Technical Report Report about the Ocean Thermal...

467

THERMAL ENERGY STORAGE IN AQUIFERS WORKSHOP  

E-Print Network (OSTI)

Survey of Thermal Energy Storage in Aquifers Coupled withconcept of thermal energy storage in aquifers was suggestedAnnual Thermal Energy Storage Contractors' Information

Authors, Various

2011-01-01T23:59:59.000Z

468

Liquid metal thermal electric converter  

DOE Patents (OSTI)

A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

Abbin, Joseph P. (Albuquerque, NM); Andraka, Charles E. (Albuquerque, NM); Lukens, Laurance L. (Albuquerque, NM); Moreno, James B. (Albuquerque, NM)

1989-01-01T23:59:59.000Z

469

Energy loss of nuclear fragments in partially ionized materials of high atomic number  

Science Journals Connector (OSTI)

Methods used for the computation of the stopping power of high-atomic-number media to light and heavy nuclear fragments in un-ionized and completely ionized states are reasonably well developed. This is not the case for partially ionized states. We propose a method that bridges these two extremes and discuss applications of the method to ? particles and fission fragments in uranium at extreme temperatures and densities.

R. A. Lewis; G. A. Smith; W. S. Toothacker

1991-07-01T23:59:59.000Z

470

Low Conductivity Thermal Barrier Coatings  

E-Print Network (OSTI)

Low Conductivity Thermal Barrier Coatings A Dissertation Presented to The Faculty of the School conductivity of the coatings. The minimum thermal conductivity occurs at a low rotation rate and is 0.8 W intrinsic thermal conductivity, good phase stability and greater resistance to sintering and CMAS attack

Wadley, Haydn

471

LSPE Interim Stowage Thermal Constraints  

E-Print Network (OSTI)

-arm and thermal battery timers require operating temperatures at or above +40°F for reliable starting when·, ' LSPE Interim Stowage Thermal Constraints· Nl,;. ATM1080 PAGE 1 OF 13 DATE 15 December l97l constraints required for thermal integrity are defined. Prepared by:.:Z4·:..=..-~31!::..--.::..·~-:·::....-c

Rathbun, Julie A.

472

Reactor Thermal-Hydraulics  

NLE Websites -- All DOE Office Websites (Extended Search)

Thermal-Hydraulics Thermal-Hydraulics Dr. Tanju Sofu, Argonne National Laboratory In a power reactor, the energy produced in fission reaction manifests itself as heat to be removed by a coolant and utilized in a thermodynamic energy conversion cycle to produce electricity. A simplified schematic of a typical nuclear power plant is shown in the diagram below. Primary coolant loop Steam Reactor Heat exchanger Primary pump Secondary pump Condenser Turbine Water Although this process is essentially the same as in any other steam plant configuration, the power density in a nuclear reactor core is typically four orders of magnitude higher than a fossil fueled plant and therefore it poses significant heat transfer challenges. Maximum power that can be obtained from a nuclear reactor is often limited by the

473

Thermalization through parton transport  

E-Print Network (OSTI)

A radiative transport model is used to study kinetic equilibration during the early stage of a relativistic heavy ion collision. The parton system is found to be able to overcome expansion and move toward thermalization via parton collisions. Scaling behaviors show up in both the pressure anisotropy and the energy density evolutions. In particular, the pressure anisotropy evolution shows an approximate alpha_s scaling when radiative processes are included. It approaches an asymptotic time evolution on a time scale of 1 to 2 fm/c. The energy density evolution shows an asymptotic time evolution that decreases slower than the ideal hydro evolution. These observations indicate that partial thermalization can be achieved and viscosity is important for the evolution during the early longitudinal expansion stage of a relativistic heavy ion collision.

Bin Zhang

2009-09-03T23:59:59.000Z

474

Ion distribution around a charged rod in one and two component solvents: Preferential solvation and first order ionization phase transition  

E-Print Network (OSTI)

In one and two component solvents, we calculate the counterion distribution around a charged rod treating the degree of ionization $\\alpha$ as an annealed variable dependent on its local environment. In the one component case, $\\alpha$ is determined under various conditions without and with salt. In the two component case, we take into account the preferential solvation of the counterions and the ionized monomers and the short-range interaction between the rod and the solvent without salt. It then follows a composition-dependent mass action law. Mesoscopic variations of the composition and the counterions are produced around a chraged rod, which sensitively depend on various parameters of the molecular interactions. Furthermore, we predict a first order phase transition of weak-to-strong dissociation for strong preferential solvation. It can occur in expanded states of a polymer chain. This transition line starts from a point on the solvent coexistence curve and ends at a critical point in the plane of the temperature and the solvent composition. The composition change around a charged rod is long-ranged near the solvent critical point.

Ryuichi Okamoto; Akira Onuki

2009-05-10T23:59:59.000Z

475

Accretion disk and ionized absorber of the 9.7-hour dipping black hole binary MAXI J1305-704  

E-Print Network (OSTI)

We report the results from X-ray studies of the newly discovered black hole candidate MAXI J1305-704 based on Suzaku and Swift observations in the low/hard and high/soft states, respectively. The long Suzaku observation shows two types of clear absorption dips, both of which recur on a dip interval of 9.74 +- 0.04 hours, which we identify with the orbital period. There is also partially ionized absorption in the non-dip (persistent) emission in both the high/soft state and, very unusually, the low/hard state. However, this absorption (in both states) has substantially lower ionization than that seen in other high inclination systems, where the material forms a homogeneous disk wind. Here instead the absorption is most probably associated with clumpy, compact structures associated with the dipping material, which we see uniquely in this source likely because we view it at a very large inclination angle. A large inclination angle is also favored, together with a low black hole mass, to explain the high disk tem...

Shidatsu, Megumi; Nakahira, Satoshi; Done, Chris; Morihana, Kumiko; Sugizaki, Mutsumi; Mihara, Tatehiro; Hori, Takafumi; Negoro, Hitoshi; Kawai, Nobuyuki; Yamaoka, Kazutaka; Ebisawa, Ken; Matsuoka, Masaru; Serino, Motoko; Yoshikawa, Tatsuhito; Nagayama, Takahiro; Matsunaga, Noriyuki

2013-01-01T23:59:59.000Z

476

11 - Stresses due to Change of Air Temperature and Superficial Thermal Insulation  

Science Journals Connector (OSTI)

Experience shows that most cracks in mass concrete structures are originally superficial cracks, but some of them may become larger and deeper cracks later on which will reduce the safety and durability of the structure. Thermal insulation is the most efficient measure for preventing superficial cracks of mass concrete structures.

Zhu Bofang

2014-01-01T23:59:59.000Z

477

The Influence of Thermal Pressure on Equilibrium Models of Hypermassive Neutron Star Merger Remnants  

E-Print Network (OSTI)

The merger of two neutron stars leaves behind a rapidly spinning hypermassive object whose survival is believed to depend on the maximum mass supported by the nuclear equation of state, angular momentum redistribution by (magneto-)rotational instabilities, and spindown by gravitational waves. The high temperatures (~5-40 MeV) prevailing in the merger remnant may provide thermal pressure support that could increase its maximum mass and, thus, its life on a neutrino-cooling timescale. We investigate the role of thermal pressure support in hypermassive merger remnants by computing sequences of spherically-symmetric and axisymmetric uniformly and differentially rotating equilibrium solutions to the general-relativistic stellar structure equations. Using a set of finite-temperature nuclear equations of state, we find that hot maximum-mass critically spinning configurations generally do not support larger baryonic masses than their cold counterparts. However, subcritically spinning configurations with mean density of less than a few times nuclear saturation density yield a significantly thermally enhanced mass. Even without decreasing the maximum mass, cooling and other forms of energy loss can drive the remnant to an unstable state. We infer secular instability by identifying approximate energy turning points in equilibrium sequences of constant baryonic mass parametrized by maximum density. Energy loss carries the remnant along the direction of decreasing gravitational mass and higher density until instability triggers collapse. Since configurations with more thermal pressure support are less compact and thus begin their evolution at a lower maximum density, they remain stable for longer periods after merger.

J. D. Kaplan; C. D. Ott; E. P. O'Connor; K. Kiuchi; L. Roberts; M. Duez

2013-06-17T23:59:59.000Z

478

Thermal energy storage  

Science Journals Connector (OSTI)

Various types of thermal stares for solar systems are surveyed which include: long-term water stores for solar systems; ground storage using soil as an interseasonal energy store; ground-water aquifers; pebble or rock bed storage; phase change storage; solar ponds; high temperature storage; and cold stores for solar air conditioning system. The use of mathematical models for analysis of the storage systems is considered

W.E.J. Neal

1981-01-01T23:59:59.000Z