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Note: This page contains sample records for the topic "determination silica polymer" 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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1

Iron acetylacetonate complex anchored on silica xerogel polymer  

Science Journals Connector (OSTI)

Iron(III) acetylacetonate complex immobilized on silica surface was obtained by the following three steps synthesis: (i) synthesis of organic precursor (acacsil) containing the acetylacetonate (acac) group; (ii) simultaneous polycondensation of the acacsil with the tetraethylorthosilicate (TEOS) by the sol–gel method resulting in the acac/silica xerogel; and (iii) complexation of the Fe(III) on the acac sites of the xerogel surface forming a Fe-acac/silica xerogel. The xerogels, acac/silica and Fe-acac/silica, are hybrid polymers that present a covalent organic/inorganic interface between the acac groups and silica. Xerogels were characterized by using scanning electron microscopy, energy dispersive spectroscopy, infrared spectroscopy, N2 adsorption desorption isotherms (pore size distribution and surface area) and elemental analysis. The Fe-acac/silica xerogel was tested as heterogeneous catalyst for the cis-cyclooctene epoxidation, employing the same conditions of the homogeneous Mukaiyama system.

Marcia C. Brasil; Edilson V. Benvenutti; José R. Gregório; Annelise E. Gerbase

2005-01-01T23:59:59.000Z

2

Polymer/Silica Composite Films as Luminescent Oxygen Sensors  

Science Journals Connector (OSTI)

10-14 In this technique, an object (a model airplane or wing, a turbine blade, or an automobile) coated with an oxygen-sensing polymer coating (“pressure-sensitive paint,” PSP) is examined in a wind tunnel. ... To examine the influence of the silica particles on oxygen diffusion and oxygen permeation in these films, we carried out both time-scan and pulsed-laser experiments as a function of silica content on films containing PtOEP. ... We rationalize this result by imagining that oxygen adsorption onto the silica surface is diffusion-controlled. Fickian diffusion through the PDMS matrix controls the rate of quenching of dye molecules bound to the silica particles. ...

Xin Lu; Ian Manners; Mitchell A. Winnik

2001-03-06T23:59:59.000Z

3

Photo-Alignment Behavior of Mesoporous Silica Thin Films Synthesized on a Photo-Cross-Linkable Polymer Film  

Science Journals Connector (OSTI)

Photo-Alignment Behavior of Mesoporous Silica Thin Films Synthesized on a Photo-Cross-Linkable Polymer Film ... Photo-aligning and micropatterning techniques for mesochannels of a silica thin film using a photo-cross-linkable polymer film with a cinnamoyl group are proposed. ... We propose herein a new photo-aligning and micropatterning technique for mesochannels of a silica thin film using a photo-cross-linkable polymer film with a cinnamoyl group. ...

Haruhiko Fukumoto; Shusaku Nagano; Nobuhiro Kawatsuki; Takahiro Seki

2006-02-11T23:59:59.000Z

4

Smectic ordering in polymer liquid crystal-silica aerogel nanocomposites  

Science Journals Connector (OSTI)

Two series of side chain liquid crystal (SCLC) polyacrylate-silica aerogel nanocomposites have been investigated by small-angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC). The first se...

H. Westfahl Jr.

2005-02-01T23:59:59.000Z

5

Dynamics at the Polymer/Nanoparticle Interface in Poly(2-vinylpyridine)/Silica Nanocomposites.  

SciTech Connect (OSTI)

The static and dynamic properties of poly(2-vinylpyridine)/silica nanocomposites are investigated by temperature modulated differential scanning calorimetry, broadband dielectric spectroscopy (BDS), small-angle X-ray scattering (SAXS), and transmission electron microscopy. Both BDS and SAXS detect the existence of an interfacial polymer layer on the surface of nanoparticles. The results show that whereas the calorimetric glass transition temperature varies only weakly with nanoparticle loading, the segmental mobility of the polymer interfacial layer is slower than the bulk polymer by 2 orders of magnitude. Detailed analysis of BDS and SAXS data reveal that the interfacial layer has a thickness of 4 6 nm irrespective of the nanoparticle concentration. These results demonstrate that in contrast to some recent articles on polymer nanocomposites, the interfacial polymer layer is by no means a dead layer . However, its existence might provide some explanation for controversies surrounding the dynamics of polymer nanocomposites.

Holt, Adam P [ORNL] [ORNL; Griffin, Phillip [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL)] [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Bocharova, Vera [ORNL] [ORNL; Agapov, Alexander L [ORNL] [ORNL; Imel, Adam E [ORNL] [ORNL; Dadmun, Mark D [ORNL] [ORNL; Sangoro, Joshua R [ORNL] [ORNL; Sokolov, Alexei P [ORNL] [ORNL

2014-01-01T23:59:59.000Z

6

Mechanical behavior of silica optical fibers coated with low index, low surface energy perfluorinated polymer  

E-Print Network [OSTI]

based on perfluorinated polymer were prepared for use as UV-curable optical cladding for silica fibers fibers, with a core doped with rare earth elements, could potentially be used as laser fibers but require special optical cladding. This cladding should have a low refractive index, low modulus of elasticity

Matthewson, M. John

7

Improved Adhesion of Dense Silica Coatings on Polymers by Atmospheric Plasma Pretreatment  

Science Journals Connector (OSTI)

Improved Adhesion of Dense Silica Coatings on Polymers by Atmospheric Plasma Pretreatment ... In another study,(7) which compared the treatments of low- and atmospheric-pressure plasmas, the authors reported that the low-pressure plasma treatment increased the adhesion with extended treatment time but prolonged atmospheric-pressure plasma treatment decreased the adhesion to epoxy. ... The authors begin with a brief overview of adhesion theory, and of the physics and chem. of cold plasmas. ...

Linying Cui; Alpana N. Ranade; Marvi A. Matos; Geraud Dubois; Reinhold H. Dauskardt

2013-08-13T23:59:59.000Z

8

Tailoring Structure Property Relationships and Elastic Phenomenon in Native and Polymer Reinforced Silica Aerogels.  

E-Print Network [OSTI]

?? The focus of this work was to study the effects of flexible silica backbones on elastic properties of silica aerogels. Two routes were examined.… (more)

Randall, Jason P.

2010-01-01T23:59:59.000Z

9

Polymer reinforced aerogels and composites A. Polyimide crosslinked aerogels B. Silica-polymethylmethacrylate composites .  

E-Print Network [OSTI]

??"Crosslinking of aerogels is a promising approach to combine the advantages of inorganic and polymeric materials. In the present study, two types of polyimide-silica hybrid… (more)

Patil, Vishal U., 1981-

2008-01-01T23:59:59.000Z

10

Composite Polymer Electrolytes Based on Poly(ethylene glycol) and Hydrophobic Fumed Silica: Dynamic  

E-Print Network [OSTI]

utilized in electrolyte processing. Introduction Rechargeable lithium batteries employing solid elec electrolytes based on poly(ethylene oxide) (PEO).1 Solid polymer electrolytes can potentially eliminate battery* Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695

Raghavan, Srinivasa

11

Aminosilane-Grafted Polymer/Silica Hollow Fiber Adsorbents for CO2 Capture from Flue Gas  

Science Journals Connector (OSTI)

In this approach, polymeric hollow fibers similar to those already prepared on commercial scales for membrane gas separations are prepared and loaded with large volumes of solid CO2 adsorbing materials. ... In this regard, the hollow fiber RTSA process is ideally suited for application of typical silica amine adsorbents, as it (i) allows for effective heat integration,(11) (ii) gives fast cycle times (expected to be on the order of 2–4 min),(8) and (iii) minimizes contact of aminosilica-adsorbents with high-temperature steam, which can degrade the adsorbent. ... The moles of CO2 adsorbed were calculated by integration of the area bounded by the CO2 breakthrough front and the He breakthrough front from the initial concentration to the final equilibration concentration. ...

Fateme Rezaei; Ryan P. Lively; Ying Labreche; Grace Chen; Yanfang Fan; William J. Koros; Christopher W. Jones

2013-03-29T23:59:59.000Z

12

Determination of laser damage initiation probability and growth on fused silica scratches  

SciTech Connect (OSTI)

Current methods for the manufacture of optical components inevitably leaves a variety of sub-surface imperfections including scratches of varying lengths and widths on even the finest finishes. It has recently been determined that these finishing imperfections are responsible for the majority of laser-induced damage for fluences typically used in ICF class lasers. We have developed methods of engineering subscale parts with a distribution of scratches mimicking those found on full scale fused silica parts. This much higher density of scratches provides a platform to measure low damage initiation probabilities sufficient to describe damage on large scale optics. In this work, damage probability per unit scratch length was characterized as a function of initial scratch width and post fabrication processing including acid-based etch mitigation processes. The susceptibility of damage initiation density along scratches was found to be strongly affected by the post etching material removal and initial scratch width. We have developed an automated processing procedure to document the damage initiations per width and per length of theses scratches. We show here how these tools can be employed to provide predictions of the performance of full size optics in laser systems operating at 351 nm. In addition we use these tools to measure the growth rate of a damage site initiated along a scratch and compare this to the growth measured on an isolated damage site.

Norton, M A; Carr, C W; Cross, D A; Negres, R A; Bude, J D; Steele, W A; Monticelli, M V; Suratwala, T I

2010-10-26T23:59:59.000Z

13

A New Protocol To Determine the Solubility of Drugs into Polymer Matrixes  

Science Journals Connector (OSTI)

A New Protocol To Determine the Solubility of Drugs into Polymer Matrixes ... For all the experiments, the sample was placed in an open aluminum pan (container with no cover) and was flushed with highly pure nitrogen gas. ... Forster, A.; Hempenstall, J.; Rades, T.Characterization of glass solutions of poorly water-soluble drugs produced by melt extrusion with hydrophilic amorphous polymers J. Pharm. ...

Aurélien Mahieu; Jean-François Willart; Emeline Dudognon; Florence Danède; Marc Descamps

2012-12-19T23:59:59.000Z

14

silica glass  

Science Journals Connector (OSTI)

...any amorphous, pale yellow to pale green natural silica glass such as moldavite, Libyan Desert glass, contains nearly 98% silica. RI:...

2009-01-01T23:59:59.000Z

15

Competitive adsorption of (phosphorylated) ethoxylated styrene oxide polymer and polyacrylic acid on silica coated iron oxide pigment  

Science Journals Connector (OSTI)

Abstract The colloidal stabilization in waterbased paint is poorly understood due to its complexity in composition, usually containing mixtures of particles and of surface active agents (“dispersants”). In this study we make a step forward by analyzing the competitive adsorption of a few widely used dispersants on a typical inorganic pigment (70 nm sized Fe2O3-based red pigment; surface treated with silica; negative zetapotential at pH ? 7). The supposition is that any particle type in paint needs sufficient adsorbed dispersant in order to be stable. Thus, we investigate, for two combinations of two dispersants, how they mutually affect their adsorption at that pigment. Also the “single” adsorption of these dispersants was investigated, thus in the absence of the other. The dispersants are an anionic, polyacrylic acid sodium salt (“PANa”; MW = 15,000 Da) in combination with a MW = 1500 Da blockcopolymer of styrene oxide (SO) and ethoxylene (EO), either or not endcapped by a phosphate group (P). The adsorption behavior was analyzed by size exclusion chromatography of the processed supernatant of the pigment dispersion. \\{PANa\\} and SO–EO–P adsorb for electrostatic reasons while SO–EO has affinity only to an organic surface. \\{PANa\\} and SO–EO–P show regular single adsorption with a plateau starting at the critical micelle concentration (cmc). SO–EO shows single adsorption only beyond its cmc based on the adsorption of full micelles. When in competition, with SO-EP-P/PANa the adsorption of SO–EO–P is lowered by ?65% while that of \\{PANa\\} is unchanged. With SO–EO/PANa the surface active species behave like in single adsorption below the cmc, but beyond the cmc a complicated phase separation occurs that cannot be based on mixed micelles. The adsorption data of \\{PANa\\} are compromised by depletion of \\{PANa\\} from interstices between particles. The anionic dispersants adsorb to the silicium oxide coated iron oxide pigment with negative surface potential because of the presence of a pH dependent relatively small number of positive iron oxide surface sites.

Wim K. Wijting; Alexander van Reenen; Jozua Laven; Rolf A.T.M. van Benthem; Gijsbertus de With

2014-01-01T23:59:59.000Z

16

Determining the Density Profile of Confined Polymer Brushes with Neutron Reflectivity  

E-Print Network [OSTI]

, University of South Florida, Florida 33620 3 Manuel Lujan Jr. Neutron Scattering Center, LANSCE-12, MS H805Determining the Density Profile of Confined Polymer Brushes with Neutron Reflectivity W. A. HAMILTON,1 G. S. SMITH,1 N. A. ALCANTAR,2 J. MAJEWSKI,3 R. G. TOOMEY,4 T. L. KUHL5 1 Center for Neutron

Kuhl, Tonya L.

17

Determination of 5-Hydroxymethylfurfural Using Derivatization Combined with Polymer Monolith Microextraction by High-Performance Liquid Chromatography  

Science Journals Connector (OSTI)

Determination of 5-Hydroxymethylfurfural Using Derivatization Combined with Polymer Monolith Microextraction by High-Performance Liquid Chromatography ... A simple and sensitive method for the determination of 5-hydroxymethylfurfural (HMF) in coffee, honey, beer, Coke, and urine by high-performance liquid chromatography (HPLC) is presented. ... Polymer monolith microextraction; high-performance liquid chromatography; 5-hydroxymethylfurfural; 2,4-dinitrophenylhydrazine ...

Jian-Yuan Wu; Zhi-Guo Shi; Yu-Qi Feng

2009-04-27T23:59:59.000Z

18

Molecular sieving silica membrane fabrication process  

DOE Patents [OSTI]

A process for producing a molecular sieve silica membrane comprising depositing a hybrid organic-inorganic polymer comprising at least one organic constituent and at least one inorganic constituent on a porous substrate material and removing at least a portion of the at least one organic constituent of the hybrid organic-inorganic polymer, forming a porous film.

Raman, Narayan K. (400 Maple St. SE., Apartment 112, Albuquerque, NM 87106); Brinker, Charles Jeffrey (14 Eagle Nest Dr., NE., Albuquerque, NM 87122)

1998-01-01T23:59:59.000Z

19

Molecular sieving silica membrane fabrication process  

DOE Patents [OSTI]

A process for producing a molecular sieve silica membrane comprising depositing a hybrid organic-inorganic polymer comprising at least one organic constituent and at least one inorganic constituent on a porous substrate material and removing at least a portion of the at least one organic constituent of the hybrid organic-inorganic polymer, forming a porous film.

Raman, Narayan K. (Monroeville, PA); Brinker, Charles Jeffrey (Albuquerque, NM)

1999-01-01T23:59:59.000Z

20

New Antifouling Silica Hydrogel  

Science Journals Connector (OSTI)

There are several potential applications for these materials (e.g., blood filtration, scaffold design, and carriers for drug delivery, among many others). ... For example, this new material can be used as a filter medium for the separation of bacterial impurities from air and water, where silica hydrogels fulfill the high-surface-area requirements for a good separation medium and the antifouling characteristics of the pCBMA brush can prevent biofilm formation, thus extending the service life of the separation medium. ... Samples were prepared by dissolving 20 mg of the polymer in 5 mL of the solvent and filtered with 0.2 ?m PTFE filters. ...

Ángela A. Beltrán-Osuna; Bin Cao; Gang Cheng; Sadhan C. Jana; Matthew P. Espe; Bimala Lama

2012-05-18T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Reinforcement of Silica Aerogels Using Silane-End-Capped Polyurethanes  

Science Journals Connector (OSTI)

Such means of reinforcement may also result in nonuniform coating of the silica network by the polymer due to an imbalance of the rate of cross-linking reactions and the rate of molecular diffusion of polymer chains inside the gel network. ... Figure 3. SEM image of TA-PU-50 aerogel (modified with 50 wt % polymer II) showing polymer-coated silica particles. ... The presence of these polymer coatings in the aerogel structure was assumed as the origin of the high contact angle and their stress–strain curve similar to “soft” materials. ...

Yannan Duan; Sadhan C. Jana; Bimala Lama; Matthew P. Espe

2013-04-23T23:59:59.000Z

22

Determination of silica scale deposition rates and thresholds applied toward protection of injection reservoirs. Quarterly progress report, July 1--September 30, 1998  

SciTech Connect (OSTI)

The program objective aims to identify the highest temperature at which silica scale will develop from partially evaporated and significantly cooled geothermal liquid. The approach involves tracking deposition of silica scale by monitoring the apparent electrical conductivity of the geothermal liquid in an isolation chamber. A decrease in apparent conductivity occurs because silica deposited on electrode surfaces is less conductive than the geothermal liquid. The major technical hurdle is building a conductivity monitoring system that is sensitive enough to distinguish between no silica deposition and almost no silica deposition, while accounting for other factors which also affect conductivity, such as temperature and varying fluid composition.

NONE

1998-11-01T23:59:59.000Z

23

Residual oil saturation determination. Wilmington micellar-polymer project. Final report  

SciTech Connect (OSTI)

The City of Long Beach, California conducted a program to obtain residual oil saturation (ROS) data in the HX/sub a/ Sand, Fault Block VB, Wilmington Field. This program utilized many complementary techniques for determining the ROS in a watered-out unconsolidated sand, typical of many reservoirs in the California Coastal Province. This program was to be performed in two stages. The first, Phase 1, was intended to determine the ROS in an area which had been flooded out during the course of a peripheral waterflood and to make a comparative analysis of current methods for determination of in-situ oil in place. The second stage, Phase 2 of the ROS program, was intended to measure the ROS after tertiary recovery by a micellar-polymer flood; however, the second phase was not carried out for lack of funds. This report describes the diagnostic tools and techniques which have been used to establish ROS. It then presents a comparative analysis of the results obtained using the different techniques. Inasmuch as the determination of in-situ oil saturation is directly dependent upon the in-situ value for porosity, it is required that the pore volume as a fraction of the reservoir rock be determined before the residual oil equation can be solved. Because of this, much of the study necessarily was concerned with measurement of porosity of the unconsolidated sand. The method finally used to obtain a very good core recovery in this highly unconsolidated sand is described. Present oil saturation and oil content of the HX/sub a/ sand in the Pilot is now believed to be better defined. This conclusion is supported by results obtained for electrical log analysis, analysis of full sized native state cores run under stress conditions, plug core analysis under stressed conditions and a Single-Well Tracer Survey. 15 references, 18 figures, 16 tables.

Staub, H.L.

1983-10-01T23:59:59.000Z

24

Scratch resistance of different silica filled resins for obturation materials  

E-Print Network [OSTI]

Scratch resistance of different silica filled resins for obturation materials B. Bilyeu1,2 , W have scratch resistance values in the range appropriate for applications as obturation materials. Keywords: Obturation materials, Polymerzsilica, Hybrids, Polymer tribology, Scratch resistance Introduction

North Texas, University of

25

Silica Scaling Removal Process  

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

Silica Scaling Removal Process Silica Scaling Removal Process Scientists at Los Alamos National Laboratory have developed a novel technology to remove both dissolved and colloidal...

26

Polymer nanocomposites based on transition metal ion modified organoclays  

E-Print Network [OSTI]

from both academic and industrial laboratories in the past several years [1,2]. Polymer nanocom in modulus, toughness, and barrier properties may be obtained. Typically, the improved properties can.polymer.2006.12.005 Polymer 48 (2007) 827e840 www.elsevier.com/locate/polymer #12;formation of silica

Frenkel, Anatoly

27

Silica extraction from geothermal water  

DOE Patents [OSTI]

A method of producing silica from geothermal fluid containing low concentration of the silica of less than 275 ppm includes the steps of treating the geothermal fluid containing the silica by reverse osmosis treatment thereby producing a concentrated fluid containing the silica, seasoning the concentrated fluid thereby producing a slurry having precipitated colloids containing the silica, and separating the silica from the slurry.

Bourcier, William L; Bruton, Carol J

2014-09-23T23:59:59.000Z

28

Mesosynthesis of ZnO?Silica Composites for Methanol Nanocatalysis  

Science Journals Connector (OSTI)

5 Mesoporous silica materials mostly of the MCM-41-type hosting polymers,6 noble metals,7 and semiconductors such as gallium nitride8 have been prepared successfully. ... 29,30 These precursors are characterized by low thermolysis temperatures and high solubility in aprotic solvents. ... Because the porous silica materials were carefully dried in a vacuum at 150 °C for 24 h, it is rather unlikely that this hydrolysis results from water adsorbed in the pore system. ...

S. Polarz; F. Neues; M. W. E. van den Berg; W. Grünert; L. Khodeir

2005-08-06T23:59:59.000Z

29

Determination of Thermophysical Properties for Polymer Films using Conduction Analysis of Laser Heating  

Science Journals Connector (OSTI)

Determination of the thermophysical properties of thin film materials is important for modeling and optimizing laser microvia drilling of organic substrates in microelectronics applications. Techniques to meas...

Chong Zhang; Islam A. Salama; Nathaniel R. Quick…

2007-06-01T23:59:59.000Z

30

Silica Scaling Removal Process  

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

Silica Scaling Removal Process Silica Scaling Removal Process Silica Scaling Removal Process Scientists at Los Alamos National Laboratory have developed a novel technology to remove both dissolved and colloidal silica using small gel particles. Available for thumbnail of Feynman Center (505) 665-9090 Email Silica Scaling Removal Process Applications: Cooling tower systems Water treatment systems Water evaporation systems Potential mining applications (produced water) Industry applications for which silica scaling must be prevented Benefits: Reduces scaling in cooling towers by up to 50% Increases the number of cycles of concentration substantially Reduces the amount of antiscaling chemical additives needed Decreases the amount of makeup water and subsequent discharged water (blowdown) Enables considerable cost savings derived from reductions in

31

Nanoengineering Strong Silica Aerogels  

Science Journals Connector (OSTI)

Nanoengineering Strong Silica Aerogels ... In the quest for strong lightweight materials, silica aerogels would be very attractive, if they were not fragile. ... Robust, Highly Thermally Stable, Core–Shell Nanostructured Metal Oxide Aerogels as High-Temperature Thermal Superinsulators, Adsorbents, and Catalysts ...

Nicholas Leventis; Chariklia Sotiriou-Leventis; Guohui Zhang; Abdel-Monem M. Rawashdeh

2002-08-23T23:59:59.000Z

32

Polymer Thermodynamics and Chain Structure Polymers display some similarities and some differences with nano-aggregates.  

E-Print Network [OSTI]

for aggregates and by the late Paul Flory of Stanford for polymer coils. Since the spring constant of a polymer of a polymer coil is largely determined by entropy, an individual polymer coil displays an increasing spring an aggregate in nanomaterials and a polymer coil in Polymer Science. The mass-fractal or minimum dimension

Beaucage, Gregory

33

Supercritical carbon dioxide behavior in porous silica aerogel  

Science Journals Connector (OSTI)

Supercritical carbon dioxide within a porous silica aerogel behaves as a two-phase system formed by a film next to the silica walls and a remaining fluid phase. Small-angle neutron scattering allows one to determine the structural parameters of the involved phases.

Ciccariello, S.

2010-11-27T23:59:59.000Z

34

CX-010520: Categorical Exclusion Determination  

Broader source: Energy.gov [DOE]

Silica Polymer Initiator Conformance Gel Applications in Geothermal Zonal Isolation CX(s) Applied: A9, B3.6, B3.11 Date: 06/17/2013 Location(s): Oklahoma Offices(s): Golden Field Office

35

Silica recovery and control in Hawaiian geothermal fluids  

SciTech Connect (OSTI)

A series of experiments was performed to investigate methods of controlling silica in waste geothermal brines produced at the HGP-A Generator Facility. Laboratory testing has shown that the rate of polymerization of silica in the geothermal fluids is highly pH dependent. At brine pH values in excess of 8.5 the suspension of silica polymers flocculated and rapidly precipitated a gelatinous silica mass. Optimum flocculation and precipitation rates were achieved at pH values in the range of 10.5 to 11.5. The addition of transition metal salts to the geothermal fluids similarly increased the rate of polymerization as well as the degree of precipitation of the silica polymer from suspension. A series of experiments performed on the recovered silica solids demonstrated that methanol extraction of the water in the gels followed by critical point drying yielded surface areas in excess of 300 M{sup 2}/g and that treatment of the dried solids with 2 N HCl removed most of the adsorbed impurities in the recovered product. A series of experiments tested the response of the waste brines to mixing with steam condensate and non-condensable gases.The results demonstrated that the addition of condensate and NCG greatly increased the stability of the silica in the geothermal brines. They also indicated that the process could reduce the potential for plugging of reinjection wells receiving waste geothermal fluids from commercial geothermal facilities in Hawaii. Conceptual designs were proposed to apply the gas re-combination approach to the disposal of geothermal waste fluids having a range of chemical compositions. Finally, these designs were applied to the geothermal fluid compositions found at Cerro Prieto, Ahuachapan, and Salton Sea.

Thomas, D.M.

1992-06-01T23:59:59.000Z

36

Silica recovery and control in Hawaiian geothermal fluids. Final report  

SciTech Connect (OSTI)

A series of experiments was performed to investigate methods of controlling silica in waste geothermal brines produced at the HGP-A Generator Facility. Laboratory testing has shown that the rate of polymerization of silica in the geothermal fluids is highly pH dependent. At brine pH values in excess of 8.5 the suspension of silica polymers flocculated and rapidly precipitated a gelatinous silica mass. Optimum flocculation and precipitation rates were achieved at pH values in the range of 10.5 to 11.5. The addition of transition metal salts to the geothermal fluids similarly increased the rate of polymerization as well as the degree of precipitation of the silica polymer from suspension. A series of experiments performed on the recovered silica solids demonstrated that methanol extraction of the water in the gels followed by critical point drying yielded surface areas in excess of 300 M{sup 2}/g and that treatment of the dried solids with 2 N HCl removed most of the adsorbed impurities in the recovered product. A series of experiments tested the response of the waste brines to mixing with steam condensate and non-condensable gases.The results demonstrated that the addition of condensate and NCG greatly increased the stability of the silica in the geothermal brines. They also indicated that the process could reduce the potential for plugging of reinjection wells receiving waste geothermal fluids from commercial geothermal facilities in Hawaii. Conceptual designs were proposed to apply the gas re-combination approach to the disposal of geothermal waste fluids having a range of chemical compositions. Finally, these designs were applied to the geothermal fluid compositions found at Cerro Prieto, Ahuachapan, and Salton Sea.

Thomas, D.M.

1992-06-01T23:59:59.000Z

37

Viscosity of silica  

Science Journals Connector (OSTI)

Experimental measurements of the viscosity of silica ( SiO 2 ) are critically examined; the best measurements show an activation energy of 515 kJ/mole above 1400 °C and 720 kJ/mole below this temperature. The diffusion of silicon and oxygen in silica have temperature dependencies close to that of the high temperature viscosity. Mechanisms of viscous flow and diffusion of silicon and oxygen in silica are proposed that involve motion of SiO molecules. Viscous flow is proposed to result from the motion of line defects composed of SiO molecules At temperatures below 1400 °C the fraction of SiO molecules in line defects changes with temperature. The relaxation of this fraction to an equilibrium value depends on the time. These proposed mechanisms are consistent with experimental measurements of silicaviscosity.

Robert H. Doremus

2002-01-01T23:59:59.000Z

38

Accelerated test methods for evaluating alkali-silica reactivity of recycled concrete aggregates.  

E-Print Network [OSTI]

??This thesis reports the findings of a study carried out to determine the effectiveness of Accelerated Tests in evaluating the Alkali-Silica Reactivity of Recycled Concrete… (more)

Johnson, Robert C (Author)

2011-01-01T23:59:59.000Z

39

Polymer Electrolyte and Polymer Battery  

Science Journals Connector (OSTI)

Generally the polymer electrolyte of the polymer battery is classified into two kinds of the electrolyte: One is a dry-type electrolyte composed of a polymer matrix and...21.1. Fig....

Toshiyuki Osawa; Michiyuki Kono

2009-01-01T23:59:59.000Z

40

Silica Geothermometers | Open Energy Information  

Open Energy Info (EERE)

Silica Geothermometers Silica Geothermometers Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Silica Geothermometers Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geochemical Techniques Exploration Sub Group: Geochemical Data Analysis Parent Exploration Technique: Liquid Geothermometry Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Thermal: Used to estimate reservoir temperatures. Dictionary.png Silica Geothermometers: No definition has been provided for this term. Add a Definition Introduction Some experts have stated that the factor that changes the risk assessment of a geothermal prospect the fastest is obtaining attractive chemical confirmation (geothermometry, gas analyses) that a thermal resource exists

Note: This page contains sample records for the topic "determination silica polymer" 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

Quantification of residual stress from photonic signatures of fused silica  

SciTech Connect (OSTI)

A commercially available grey-field polariscope (GFP) instrument for photoelastic examination is used to assess impact damage inflicted upon the outer-most pane of Space Shuttle windows made from fused silica. A method and apparatus for calibration of the stress-optic coefficient using four-point bending is discussed. The results are validated on known material (acrylic) and are found to agree with literature values to within 6%. The calibration procedure is then applied to fused-silica specimens and the stress-optic coefficient is determined to be 2.43 ± 0.54 × 10{sup ?12} Pa{sup ?1}. Fused silica specimens containing impacts artificially made at NASA’s Hypervelocity Impact Technology Facility (HIT-F), to simulate damage typical during space flight, are examined. The damage sites are cored from fused silica window carcasses and examined with the GFP. The calibrated GFP measurements of residual stress patterns surrounding the damage sites are presented.

Cramer, K. Elliott; Yost, William T. [NASA Langley Research Center, Hampton, VA 23681 (United States); Hayward, Maurice [College of William and Mary, Williamsburg, VA 23185 (United States)

2014-02-18T23:59:59.000Z

42

Silica Supported Single-Walled Carbon Nanotubes as a Modifier in Polyethylene Composites  

E-Print Network [OSTI]

Silica Supported Single-Walled Carbon Nanotubes as a Modifier in Polyethylene Composites Neal D. Mc.interscience.wiley.com). ABSTRACT: Composites have been made from single- wall carbon nanotubes in a polyethylene (PE) matrix: additives; composites; conducting polymers; nanocomposites; polyethylene INTRODUCTION Polyethylene (PE

Resasco, Daniel

43

Monolithic Composites of Silica Aerogels by Reactive Supercritical Deposition of Hydroxy-Terminated Poly(Dimethylsiloxane)  

Science Journals Connector (OSTI)

The method involves dissolution of PDMS(OH) in supercritical CO2 (scCO2) and then exposure of the aerogel samples to this single phase mixture of PDMS(OH)-CO2. ... Upon supercritical deposition, the polymer molecules were discovered to react with the hydroxyl groups on the silica aerogel surface and form a conformal coating on the surface. ...

D. Sanli; C. Erkey

2013-10-29T23:59:59.000Z

44

A New Class of Silica Crosslinked Micellar Core-Shell /nanoparticles."  

SciTech Connect (OSTI)

Micellar nanoparticles made of surfactants and polymers have attracted wide attention in the materials and biomedical community for controlled drug delivery, molecular imaging and sensing; however, their long-term stability remains a topic of intense study. Here we report a new class of robust, ultrafine (10nm) silica core-shell nanoparticles formed from silica crosslinked, individual block copolymer micelles. Compared with pure polymer micelles, the new core-shell nanoparticles have significantly improved stability and do not break down during dilution. They also achieve much higher loading capacity for a wide range of chemicals, with the entrapped molecules slowly released over a much longer period of time. A wide range of functional groups can be easily incorporated through co-condensation with the silica matrix. The potential to deliver hydrophobic agents into cancer cells has been demonstrated. Because of their unique properties, these novel core-shell nanoparticles could potentially provide a new nanomedicine platform for imaging, detection and treatment.

Huo, Qisheng; Liu, Jun; Wang, Li Q.; Jiang, Yingbing; Lambert, Timothy N.; Fang, Erica

2006-05-17T23:59:59.000Z

45

Molecular-dynamics simulations of thin polyisoprene films confined between amorphous silica substrates  

SciTech Connect (OSTI)

Constant temperature–constant pressure (NpT) molecular-dynamics computer simulations have been carried out for the united-atom model of a non-crosslinked (1,4) cis-polyisoprene (PI) melt confined between two amorphous, fully coordinated silica surfaces. The Lennard-Jones 12-6 potential was implemented to describe the polymer–silica interactions. The thickness H of the produced PI–silica film has been varied in a wide range, 1 < H/R{sub g} < 8, where R{sub g} is the individual PI chain radius of gyration measured under the imposed confinement. After a thorough equilibration, the PI film stratified structure and polymer segmental dynamics have been studied. The chain structure in the middle of the films resembles that in a corresponding bulk, but the polymer-density profile shows a pronounced ordering of the polymer segments in the vicinity of silica surfaces; this ordering disappears toward the film middles. Tremendous slowing down of the polymer segmental dynamics has been observed in the film surface layers, with the segmental relaxation more than 150 times slower as compared to that in a PI bulk. This effect increases with decreasing the polymer-film thickness. The segmental relaxation in the PI film middles shows additional relaxation process which is absent in a PI bulk. Even though there are fast relaxation processes in the film middle, its overall relaxation is slower as compared to that in a bulk sample. The interpretation of the results in terms of polymer glassy bridges has been discussed.

Guseva, D. V., E-mail: d.v.guseva@tue.nl [Theory of Polymers and Soft Matter, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB, Eindhoven (Netherlands); Physics Department, Chair of Polymer and Crystal Physics, M. V. Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Komarov, P. V. [Department of Theoretical Physics, Tver State University, Sadovyj per. 35, 170002 Tver, Russia and Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova st. 28, 119991 Moscow (Russian Federation)] [Department of Theoretical Physics, Tver State University, Sadovyj per. 35, 170002 Tver, Russia and Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova st. 28, 119991 Moscow (Russian Federation); Lyulin, Alexey V. [Theory of Polymers and Soft Matter, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB, Eindhoven (Netherlands)] [Theory of Polymers and Soft Matter, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB, Eindhoven (Netherlands)

2014-03-21T23:59:59.000Z

46

Durable polymer-aerogel based superhydrophobic coatings, a composite material  

DOE Patents [OSTI]

Provided are polymer-aerogel composite coatings, devices and articles including polymer-aerogel composite coatings, and methods for preparing the polymer-aerogel composite. The exemplary article can include a surface, wherein the surface includes at least one region and a polymer-aerogel composite coating disposed over the at least one region, wherein the polymer-aerogel composite coating has a water contact angle of at least about 140.degree. and a contact angle hysteresis of less than about 1.degree.. The polymer-aerogel composite coating can include a polymer and an ultra high water content catalyzed polysilicate aerogel, the polysilicate aerogel including a three dimensional network of silica particles having surface functional groups derivatized with a silylating agent and a plurality of pores.

Kissel, David J; Brinker, Charles Jeffrey

2014-03-04T23:59:59.000Z

47

Structural Investigations of Silica Polyamine Composites: Surface Coverage, Metal Ion Coordination, and Ligand Modification  

SciTech Connect (OSTI)

Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake studies show increases in Cu(II) capacity and/or an improvement in Cu(II) mass-transfer kinetics. The effect of polymer molecular weight upon Cu(II) capacity was investigated for each polyamine. Substantial differences in Cu(II) capacity between 50,000 MW poly(vinylamine) (PVA) and >1000 MW PVA were evident. Similar differences between 25,000 MW poly(ethyleneimine) (PEI) and 1200 MW PEI were found. The mass-transfer kinetics was shown to be improved for composites prepared using a large fraction of MTCS in the reagent silane mixture. This resulted in substantial improvements in the 10% breakthrough Cu(II) capacity for PVA (50 000 MW). PEI composites were further modified to form an amino-acetate ligand. The impact of the MTCS:CPTCS silane ratio on the acetate ligand loading and ultimately on the Cu(II) capacity at pH 2 was investigated. A ratio of 12.5:1 was shown to result in an acetate modified PEI composite with a Cu(II) capacity 140% of the Cu(II) capacity of the same composite prepared with ''CPTCS only''.

Hughes, Mark; Nielsen, Daniel; Rosenberg, Edward; Gobetto, Roberto; Viale, Alessandra; Burton, Sarah D.; Ferel, Joseph

2006-09-13T23:59:59.000Z

48

EMSL - polymers  

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

polymers en Structures and Stabilities of (MgO)n Nanoclusters. http:www.emsl.pnl.govemslwebpublicationsstructures-and-stabilities-mgon-nanoclusters

49

Molecularly imprinted polymer coated solid-phase microextraction fibers for determination of Sudan I–IV dyes in hot chili powder and poultry feed samples  

Science Journals Connector (OSTI)

In this research, a novel strategy was developed to prepare molecularly imprinted polymer (MIP) coated solid-phase microextraction fibers on a large scale with Sudan I as template and stainless steel fibers as substrate. More than 20 fibers could be obtained in one glass tube, and the efficiency and coating repeatability were enhanced remarkably in contrast with the yield of only one fiber in our previous works. The obtained MIP-coated stainless steel fibers were characterized by homogeneous and highly cross-linked coating, good chemical and thermal stabilities, high extraction capacities, and specific selectivities to Sudan I–IV dyes. Based on the systemic optimization of extraction conditions, a simple and cost-effective method based on the coupling of MIP-coated SPME with high-performance liquid chromatography was developed for the fast and selective determination of trace Sudan I–IV dyes in hot chili powder and poultry feed samples. The limits of detection of Sudan I–IV dyes were within 2.5–4.6 ng g?1, and the spiked recoveries were in the range of 86.3–96.3% for hot chili powder sample and 84.6–97.4% for poultry feed sample.

Xiaogang Hu; Quanlin Cai; Yanan Fan; Tingting Ye; Yujuan Cao; Changjuan Guo

2012-01-01T23:59:59.000Z

50

Sample Desorption/Ionization From Mesoporous Silica  

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

51

Fundamental studies of polymer filtration  

SciTech Connect (OSTI)

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The objectives of this project were (1) to develop an enhanced fundamental understanding of the coordination chemistry of hazardous-metal-ion complexation with water-soluble metal-binding polymers, and (2) to exploit this knowledge to develop improved separations for analytical methods, metals processing, and waste treatment. We investigated features of water-soluble metal-binding polymers that affect their binding constants and selectivity for selected transition metal ions. We evaluated backbone polymers using light scattering and ultrafiltration techniques to determine the effect of pH and ionic strength on the molecular volume of the polymers. The backbone polymers were incrementally functionalized with a metal-binding ligand. A procedure and analytical method to determine the absolute level of functionalization was developed and the results correlated with the elemental analysis, viscosity, and molecular size.

Smith, B.F.; Lu, M.T.; Robison, T.W.; Rogers, Y.C.; Wilson, K.V.

1998-12-31T23:59:59.000Z

52

Hydrophobic silica aerogel reinforced with carbon nanotube for oils removal  

Science Journals Connector (OSTI)

Hydrophobic silica aerogel reinforced with carbon nanotube (CNT/silica aerogel) has been prepared by forming silica layer on carboxylated CNT via a sol–gel process. The prepared CNT/silica aerogel can bear a l...

Tao Sun; Qin Zhuo; Xin Liu; Zhaopeng Sun; Zhanjun Wu…

2014-08-01T23:59:59.000Z

53

Hybrid Silica/Polymer Aerogels Dried at Ambient Pressure  

Science Journals Connector (OSTI)

The hybrid aerogels show improved mechanical properties with respect to the corresponding inorganic aerogel (much higher energy is stored until fracture), without loss of structure or porosity. ... 4,5 These include catalysis, optics, electronics, sensors, coatings, biochemistry, medicine, and others. ... The surfaces were previously sputter-coated with a gold layer ?20 nm thick, to avoid charging effects during observation. ...

A. Fidalgo; J. P. S. Farinha; J. M. G. Martinho; M. E. Rosa; L. M. Ilharco

2007-04-24T23:59:59.000Z

54

Categorical Exclusion Determinations: Golden Field Office | Department of  

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

27, 2011 27, 2011 CX-007536: Categorical Exclusion Determination Tucson Public Building Solar Arrays CX(s) Applied: A9, B5.16 Date: 12/27/2011 Location(s): Arizona Offices(s): Golden Field Office December 27, 2011 CX-007570: Categorical Exclusion Determination EL-11-002 East Marshall High School Geothermal Project CX(s) Applied: B5.19, B2.1 Date: 12/27/2011 Location(s): Iowa Offices(s): Golden Field Office December 21, 2011 CX-007417: Categorical Exclusion Determination Shift CX(s) Applied: B5.1 Date: 12/21/2011 Location(s): Pennsylvania Offices(s): Golden Field Office December 21, 2011 CX-007409: Categorical Exclusion Determination Silica Polymer Initiator Conformance Gel Applications in Geothermal Zonal Isolation CX(s) Applied: A9, B3.6 Date: 12/21/2011 Location(s): Oklahoma

55

Surface induced disorder of nematic MBBA near silica with grafted poly(ethylene oxide)  

E-Print Network [OSTI]

909 Surface induced disorder of nematic MBBA near silica with grafted poly(ethylene oxide) H. Ben greffés, du polyoxyde d'ethylene 2000, a été étudié à l'aide des techniques suivantes : la résonance para with grafted polymers poly(ethylene oxide) 2000, has been investigated by the electron paramagnetic resonance

Paris-Sud XI, Université de

56

Categorical Exclusion Determinations: Office of Energy Efficiency and  

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

23, 2009 23, 2009 CX-000208: Categorical Exclusion Determination Recovery Act - PEM (Polymer Electrolyte Membrane) Fuel Cell Systems Providing Emergency Reserve and Backup Power CX(s) Applied: B5.1 Date: 11/23/2009 Location(s): Washington Office(s): Energy Efficiency and Renewable Energy, Golden Field Office November 23, 2009 CX-000207: Categorical Exclusion Determination NaSi (Sodium Silicide) and Na-SG (Sodium Silica Gell) Powder Hydrogen Fuel Cells CX(s) Applied: B3.6 Date: 11/23/2009 Location(s): New York Office(s): Energy Efficiency and Renewable Energy, Golden Field Office November 23, 2009 CX-000206: Categorical Exclusion Determination Michigan Biogas Center of Excellence CX(s) Applied: A9, B3.6 Date: 11/23/2009 Location(s): Flint, Michigan Office(s): Energy Efficiency and Renewable Energy, Golden Field Office

57

Silica Polyamine Composites: New Supramolecular Materials for Cation and Anion Recovery and Remediation  

SciTech Connect (OSTI)

The surface coverage of amorphous silica gels used in the synthesis of silica polyamine composites has been investigated by 29Si NMR. By diluting the polyamine anchor silane, chloropropyl trichlorosilane, with methyl trichlorosilane it was found that surface coverage could be markedly improved for a range of amine polymers after grafting to the silica surface. The commensurate decrease in the number of anchor points and increase in the number of free amines results in an increase in metal capacity and/or an improvement in capture kinetics. Solid state CPMAS-13C NMR has been employed to investigate the structure and metal ion binding of a series of these composite materials. It is reported that the highly branched polymer, poly(ethyleneimine) (PEI) exhibits much broader 13C NMR resonances than the linear polymers poly(allylamine) (PAA) and poly(vinylamine) (PVA). These results are understood in terms of the low energy conformations calculated from molecular modeling studies. Three new applications of the technology are also presented: (1) separation of lanthanides as a group from ferric ion and all other divalent ions; (2) a multi step process for recovering and concentrating the valuable metals in acid mine drainage; (3) a process for removing low level arsenic and selenium in the presence of sulfate using immobilized cations on the composite materials.

Hughes, Mark; Miranda, Paul; Nielsen, Daniel J.; Rosenberg, Edward; Gobetto, Roberto; Viale, Alessandra; Burton, Sarah D.

2006-03-01T23:59:59.000Z

58

Viscosity of Ring Polymer Melts  

Science Journals Connector (OSTI)

Viscosity of Ring Polymer Melts ... The ratio of the zero-shear viscosities of linear polymer melts ?0,linear to their ring counterparts ?0,ring at isofrictional conditions is discussed as a function of the number of entanglements Z. ... For this reason we have determined the viscosities by fitting the complex viscosity curves with different methods to obtain reliable estimates and error bars (see Supporting Information). ...

Rossana Pasquino; Thodoris C. Vasilakopoulos; Youn Cheol Jeong; Hyojoon Lee; Simon Rogers; George Sakellariou; Jürgen Allgaier; Atsushi Takano; Ana R. Brás; Taihyun Chang; Sebastian Gooßen; Wim Pyckhout-Hintzen; Andreas Wischnewski; Nikos Hadjichristidis; Dieter Richter; Michael Rubinstein; Dimitris Vlassopoulos

2013-09-17T23:59:59.000Z

59

Polymer Brushes  

Science Journals Connector (OSTI)

...DOLAN, A.K., EFFECT OF EXCLUDED VOLUME ON POLYMER DISPERSANT ACTION, PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES...prop-erties of a tagged subset of chain units. One example is the nuclear magnetic resonance (NMR) studies by Blum and co-workers...

S. T. MILNER

1991-02-22T23:59:59.000Z

60

Total Neutron Scattering in Vitreous Silica  

Science Journals Connector (OSTI)

The structure of Corning superpure vitreous silica glass has been investigated with neutrons. A new method of analysis using variable neutron wavelengths and the measurement of total scattering cross sections from transmission experiments is developed and the results are compared with those from differential x-ray scattering. The total neutron scattering method permits a simple and direct structure analysis with resolution apparently superior to x-rays. The preliminary results compare well in a first approximation analysis with the basic structure model of Warren and others and in addition the neutron-determined atomic radial distribution curve exhibits some finer details than the x-ray results. Thermal inelastic scattering of neutrons was corrected for in an approximate way.

R. J. Breen; R. M. Delaney; P. J. Persiani; A. H. Weber

1957-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Coagulation chemistries for silica removal from cooling tower water.  

SciTech Connect (OSTI)

The formation of silica scale is a problem for thermoelectric power generating facilities, and this study investigated the potential for removal of silica by means of chemical coagulation from source water before it is subjected to mineral concentration in cooling towers. In Phase I, a screening of many typical as well as novel coagulants was carried out using concentrated cooling tower water, with and without flocculation aids, at concentrations typical for water purification with limited results. In Phase II, it was decided that treatment of source or make up water was more appropriate, and that higher dosing with coagulants delivered promising results. In fact, the less exotic coagulants proved to be more efficacious for reasons not yet fully determined. Some analysis was made of the molecular nature of the precipitated floc, which may aid in process improvements. In Phase III, more detailed study of process conditions for aluminum chloride coagulation was undertaken. Lime-soda water softening and the precipitation of magnesium hydroxide were shown to be too limited in terms of effectiveness, speed, and energy consumption to be considered further for the present application. In Phase IV, sodium aluminate emerged as an effective coagulant for silica, and the most attractive of those tested to date because of its availability, ease of use, and low requirement for additional chemicals. Some process optimization was performed for coagulant concentration and operational pH. It is concluded that silica coagulation with simple aluminum-based agents is effective, simple, and compatible with other industrial processes.

Nyman, May Devan; Altman, Susan Jeanne; Stewart, Tom

2010-02-01T23:59:59.000Z

62

Silica Scale Management: Lowering Operating Costs through Improved Scale Control, and Adding Value by Extracting Marketable By-Products  

SciTech Connect (OSTI)

We are using laboratory and field experiments to design modeling tools and technology that will improve silica scale management practices in geothermal plants. Our work will help to lower operating costs through improved scale prediction and add new revenue streams from sale of mineral byproducts extracted from geothermal fluids. Improving the economics and effectiveness of scale control programs and/or extraction systems in geothermal operations requires a coupled kinetic-thermodynamic model of silica behavior. Silica scale precipitation is a multi-step process, involving a nucleation-related induction period, aqueous polymerization, condensation of polymers to form colloids, and deposition onto a solid surface. Many chemical and physical variables influence the rates of these steps and their impacts must be quantified and predictable in order to optimally control silica behavior. To date, in laboratory studies, we have quantified the effects on silica polymerization of the following set of chemical variables: Na at 500 and 2000 ppm, pH values from 5 to 9, temperatures of 25 and 50 C, and silica saturation values from 1.2 to 6 at initial dissolved silica concentrations of 600 ppm. Lowering pH both increases the induction time prior to polymerization and decreases the polymerization rate. We have successfully used a multiple regression model to predict polymerization rates from these variables. Geothermal fluids contain significant dissolved concentrations of potentially valuable mineral resources such as zinc, lithium, cesium and rubidium, but silica fouling interferes with traditional extraction methods. We are developing customized and new technologies to extract the silica as a commercial-grade commodity as well as the valuable metals. We are conducting field testing of some of these techniques at a Mammoth, CA geothermal plant using a reverse osmosis unit to concentrate the fluid, adding a commercial agglomerating agent to promote silica precipitation, and then removing the silica using a tangential flow ultrafilter. The particle size, surface area and trace impurities of the silica are characterized for comparison with commercial-grade silica products. We are also testing ion exchange resins and other functionalized materials to extract potentially economic concentrations of lithium, cesium, and rubidium that are enriched in the reverse osmosis concentrate.

Burton, E A; Bourcier, W L; Wallce, A; Bruton, C J; Leif, R

2003-06-18T23:59:59.000Z

63

Role of Polymer Segment?Particle Surface Interactions in Controlling Nanoparticle Dispersions in Concentrated Polymer Solutions  

SciTech Connect (OSTI)

The microstructure of particles suspended in concentrated polymer solutions is examined with small-angle X-ray scattering and small-angle neutron scattering. Of interest are changes to long wavelength particle density fluctuations in ternary mixtures of silica nanoparticles suspended in concentrated solutions of poly(ethylene glycol). The results are understood in terms of application of the pseudo-two-component polymer reference interaction site model (PRISM) theory modified to account for solvent addition via effective contact strength of interfacial attraction, {var_epsilon}{sub pc}, in an implicit manner. The combined experimental-theoretical study emphasizes the complex interactions between solvent, polymer, and particle surface that control particle miscibility but also demonstrate that these factors can all be understood in terms of variations of {var_epsilon}{sub pc}.

Kim, So Youn; Zukoski, Charles F. (UIUC)

2014-09-24T23:59:59.000Z

64

Electroactive Silica Nanoparticles for Biological Labeling. ...  

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

novel electrochemical immuno-biosensor based on poly(guanine)-functionalized silica nanoparticle labels and mediator-generated catalytic reaction was described. The functionalized...

65

INTERACTION OF MARINE SEDIMENTS WITH DISSOLVED SILICA  

Science Journals Connector (OSTI)

In situ, these sediments had been in contact with seawater ... with seawater of high- and low-silica con- .... water after Five months storage with sediments.

2000-02-10T23:59:59.000Z

66

Silica Supported Ceria Nanoparticles: A Hybrid Nanostructure...  

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

Nanoparticles: A Hybrid Nanostructure To Increase Stability And Surface Reactivity Of Nano-crystalline Silica Supported Ceria Nanoparticles: A Hybrid Nanostructure To Increase...

67

Conductive Polymers  

SciTech Connect (OSTI)

Electroluminescent devices such as light-emitting diodes (LED) and high-energy density batteries. These new polymers offer cost savings, weight reduction, ease of processing, and inherent rugged design compared to conventional semiconductor materials. The photovoltaic industry has grown more than 30% during the past three years. Lightweight, flexible solar modules are being used by the U.S. Army and Marine Corps for field power units. LEDs historically used for indicator lights are now being investigated for general lighting to replace fluorescent and incandescent lights. These so-called solid-state lights are becoming more prevalent across the country since they produce efficient lighting with little heat generation. Conductive polymers are being sought for battery development as well. Considerable weight savings over conventional cathode materials used in secondary storage batteries make portable devices easier to carry and electric cars more efficient and nimble. Secondary battery sales represent an $8 billion industry annually. The purpose of the project was to synthesize and characterize conductive polymers. TRACE Photonics Inc. has researched critical issues which affect conductivity. Much of their work has focused on production of substituted poly(phenylenevinylene) compounds. These compounds exhibit greater solubility over the parent polyphenylenevinylene, making them easier to process. Alkoxy substituted groups evaluated during this study included: methoxy, propoxy, and heptyloxy. Synthesis routes for production of alkoxy-substituted poly phenylenevinylene were developed. Considerable emphasis was placed on final product yield and purity.

Bohnert, G.W.

2002-11-22T23:59:59.000Z

68

Time-resolved plasma measurements in Ge-doped silica exposed to infrared femtosecond laser  

SciTech Connect (OSTI)

Using a time-resolved interferometric technique, we study the laser-induced carrier-trapping dynamics in SiO{sub 2} and Ge-doped SiO{sub 2}. The fast trapping of electrons in the band gap is associated with the formation of self-trapped excitons (STE). The STE trapping is doping dependent in SiO{sub 2}. The mean trapping time of electrons excited in the conduction band was found to be significantly lower in Ge-doped silica (75 {+-} 5 fs) when compared to pure silica (155 {+-} 5 fs). At our concentration level, this indicates that the plasma properties are determined by the presence of easily ionizable states such as the presence of Ge atoms in the glass network. Therefore, we suggest that in Ge-doped silica there exist an additional trapping pathway that leads to a significantly faster excitons trapping and a higher plasma density when compared to undoped silica.

Lancry, M.; Poumellec, B. [LPCES/ICMMO, UMR CNRS-UPS 8182, Universite Paris Sud 11, Batiment 410, 91405 Orsay (France); Groothoff, N.; Canning, J. [Interdisciplinary Photonics Laboratories, School of Chemistry, University of Sydney, 206 NIC, ATP, Eveleigh, NSW, 1340 (Australia); Guizard, S.; Fedorov, N. [Laboratoire des Solides Irradies/CEA IRAMIS, Ecole Polytechnique, Palaiseau (France)

2011-12-15T23:59:59.000Z

69

Fluorescent Silica Nanoparticles with Efficient Urinary Excretion for Nanomedicine  

Science Journals Connector (OSTI)

Fluorescent Silica Nanoparticles with Efficient Urinary Excretion for Nanomedicine ... The emerging nanomedicine landscape ... Core-shell silica nanoparticles as fluorescent labels for nanomedicine ...

Andrew A. Burns; Jelena Vider; Hooisweng Ow; Erik Herz; Oula Penate-Medina; Martin Baumgart; Steven M. Larson; Ulrich Wiesner; Michelle Bradbury

2008-12-19T23:59:59.000Z

70

Synthesis of supported carbon nanotubes in mineralized silica...  

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

supported carbon nanotubes in mineralized silica-wood composites. Synthesis of supported carbon nanotubes in mineralized silica-wood composites. Abstract: Multiwall carbon...

71

Structure of Random Porous Materials: Silica Aerogel  

Science Journals Connector (OSTI)

Using small-angle x-ray scattering, we show that porous silica aerogel has a fractal backbone structure. The observed structure is traced to the underlying chemical (polymerization) and physical (colloid aggregation) growth processes. Comparison of scattering curves for aerogel with silica aggregates confirms this interpretation.

Dale W. Schaefer and Keith D. Keefer

1986-05-19T23:59:59.000Z

72

Hydrogenolysis of methyl formate over copper on silica. I. Study of surface species by in situ infrared spectroscopy  

SciTech Connect (OSTI)

The hydrogenolysis of methyl formate to methanol over silica-supported copper has been studied using in situ infrared spectroscopy coupled with simultaneous determination of rate. Under flow reaction conditions two forms of adsorbed methyl formate exist. One has a carbonyl absorption at 1726 cm/sup -1/ and is bound to the support by the hydrogen bonding with a heat of adsorption of 65 kJ mol/sup -1/. The second absorbs at 1666 cm/sup -1/ and is bound to copper with an approximate heat of adsorption of 140 kJ mol/sup -1/. At 457 K the hydrogenolysis rate is directly proportional to the band intensity of the latter and hence it, or another species in equilibrium with it, is involved in the rate-determining step. Adsorption of CO from CO/H/sub 2/ mixtures gives rise to a single infrared band at 2117 cm/sup -1/, the corresponding heat of adsorption being 60 kJ mol/sup -1/. Competitive measurements under hydrogenolysis conditions show that methyl formate will partially displace adsorbed CO and not vice versa. Nonetheless CO does reversibly inhibit the rate and this is attributed to its adsorption displacing hydrogen from the surface. The lower concentration of surface hydrogen also reduces the rate of hydrogenation of a formaldehyde intermediate leading to its deposition as a polymer as revealed by infrared bands at 1483 and 1375 cm/sup -1/. The same polymer accretes more rapidly during the reverse methanol to methyl formate reaction for which CO is a substantial by-product and hydrogen pressures are much lower than used for hydrogenolysis. Continuous deactivation of the catalyst is then observed.

Monti, D.M.; Cant, N.W.; Trimm, D.L.; Wainwright, M.S.

1986-07-01T23:59:59.000Z

73

Natural hydrous amorphous silica: Quantitation of network speciation and hydroxyl content by 29Si MAS NMR and vibrational spectroscopy  

Science Journals Connector (OSTI)

...technological and industrial applications (e.g., desiccants, aerogels, SiO2 films in semiconductors). In natural settings, amorphous...1990) NMR determination of the fractal dimension in silica aerogels. Physical Review Letters, 65, 614-617. Engelhardt, G...

Steven M. Chemtob; George R. Rossman; Jonathan F. Stebbins

74

Viscosity of polymer solutions  

Science Journals Connector (OSTI)

Viscosity of polymer solutions ... Abstracts for Volume 5A, Number 2. This program contains three components: "Density of Liquids", "Viscosity of Liquids", and "Viscosity of Polymer Solutions". ...

Gary L. Bertrand

1992-01-01T23:59:59.000Z

75

Fluorescent Functionalized Mesoporous Silica for Radioactive Material Extraction  

SciTech Connect (OSTI)

Mesoporous silica with covalently bound salicylic acid molecules incorporated in the structure was synthesized with a one-pot, co-condensation reaction at room temperature. The as-synthesized material has a large surface area, uniform particle size, and an ordered pore structure as determined by characterization with transmission electron microscopy, thermal gravimetric analysis, and infrared spectra, etc. Using the strong fluorescence and metal coordination capability of salicylic acid, functionalized mesoporous silica (FMS) was developed to track and extract radionuclide contaminants, such as uranyl [U(VI)] ions encountered in subsurface environments. Adsorption measurements showed a strong affinity of the FMS toward U(VI) with a Kd value of 105 mL/g, which is four orders of magnitude higher than the adsorption of U(VI) onto most of the sediments in natural environments. The new materials have a potential for synergistic environmental monitoring and remediation of the radionuclide U(VI) from contaminated subsurface environments.

Li, Juan; Zhu, Kake; Shang, Jianying; Wang, Donghai; Nie, Zimin; Guo, Ruisong; Liu, Chongxuan; Wang, Zheming; Li, Xiaolin; Liu, Jun

2012-08-01T23:59:59.000Z

76

Supercritical carbon dioxide behavior in porous silica aerogel  

SciTech Connect (OSTI)

Analysis of the tails of the small-angle neutron scattering (SANS) intensities relevant to samples formed by porous silica and carbon dioxide at pressures ranging from 0 to 20 MPa and at temperatures of 308 and 353 K confirms that the CO2 fluid must be treated as a two-phase system. The first of these phases is formed by the fluid closer to the silica wall than a suitable distance [delta] and the second by the fluid external to this shell. The sample scattering-length densities and shell thicknesses are determined by the Porod invariants and the oscillations observed in the Porod plots of the SANS intensities. The resulting matter densities of the shell regions (thickness 15-35 {angstrom}) are approximately equal, while those of the outer regions increase with pressure and become equal to the bulk CO2 at the higher pressures only in the low-temperature case.

Ciccariello, Salvino [Universita di Padova; Melnichenko, Yuri B [ORNL; He, Lilin [ORNL

2011-01-01T23:59:59.000Z

77

Evaluation of Rexene polymers in hot mixed asphalt concrete  

E-Print Network [OSTI]

Committee: Dr. Dallas N. Little The objective of this research was to provide a comprehensive characterization of asphalt binders and paving mixtures modified with four polymers produced by the Rexene Products Company (Odessa, Texas). The four polymers... on control asphalt cements and polymer modified asphalt cements to quantify the effects of the Rexene polymers. Most importantly, the binder study was designed to determine the temperature susceptibility of the binders. Asphalt cements from three...

Rodriguez, Mary Anne Reese

1991-01-01T23:59:59.000Z

78

Highly efficient carbon dioxide capture with a porous organic polymer impregnated with  

E-Print Network [OSTI]

Highly efficient carbon dioxide capture with a porous organic polymer impregnated environmental crises such as global warming and ocean acidication, efficient carbon dioxide (CO2) capture As CO2 capture mate- rials, numerous solid adsorbents such as silica5 and carbon materials,6 metal

Paik Suh, Myunghyun

79

Silica Nanoparticles and Frameworks from Rice Husk Biomass  

Science Journals Connector (OSTI)

Silica Nanoparticles and Frameworks from Rice Husk Biomass ... silica nanoparticles; rice husk; porous; biomass; hierarchical ... (22-25) Although the silica structures from RHs appear to be much less complicated and less visually attractive compared to the ones from diatoms, the large quantities of RH biomass offer an opportunity for mass production of nanostructured silica for industrial applications. ...

Weixing Wang; Jarett C. Martin; Xiaotian Fan; Aijie Han; Zhiping Luo; Luyi Sun

2011-12-29T23:59:59.000Z

80

Dynamic Fracture Toughness of Polymer Composites  

E-Print Network [OSTI]

that of defense or transport. In this project, the focus is on determining dynamic fracture toughness property of fiber reinforced polymer composites by using a combined numerical- experimental methodology. Impact tests are conducted on Split-Hopkinson pressure...

Harmeet Kaur

2012-02-14T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Monodisperse metal nanoparticle catalysts on silica mesoporous supports: synthesis, characterizations, and catalytic reactions  

SciTech Connect (OSTI)

The design of high performance catalyst achieving near 100% product selectivity at maximum activity is one of the most important goals in the modern catalytic science research. To this end, the preparation of model catalysts whose catalytic performances can be predicted in a systematic and rational manner is of significant importance, which thereby allows understanding of the molecular ingredients affecting the catalytic performances. We have designed novel 3-dimensional (3D) high surface area model catalysts by the integration of colloidal metal nanoparticles and mesoporous silica supports. Monodisperse colloidal metal NPs with controllable size and shape were synthesized using dendrimers, polymers, or surfactants as the surface stabilizers. The size of Pt, and Rh nanoparticles can be varied from sub 1 nm to 15 nm, while the shape of Pt can be controlled to cube, cuboctahedron, and octahedron. The 3D model catalysts were generated by the incorporation of metal nanoparticles into the pores of mesoporous silica supports via two methods: capillary inclusion (CI) and nanoparticle encapsulation (NE). The former method relies on the sonication-induced inclusion of metal nanoparticles into the pores of mesoporous silica, whereas the latter is performed by the encapsulation of metal nanoparticles during the hydrothermal synthesis of mesoporous silica. The 3D model catalysts were comprehensively characterized by a variety of physical and chemical methods. These catalysts were found to show structure sensitivity in hydrocarbon conversion reactions. The Pt NPs supported on mesoporous SBA-15 silica (Pt/SBA-15) displayed significant particle size sensitivity in ethane hydrogenolysis over the size range of 1-7 nm. The Pt/SBA-15 catalysts also exhibited particle size dependent product selectivity in cyclohexene hydrogenation, crotonaldehyde hydrogenation, and pyrrole hydrogenation. The Rh loaded SBA-15 silica catalyst showed structure sensitivity in CO oxidation reaction. In addition, Pt-mesoporous silica core-shell structured NPs (Pt{at}mSiO{sub 2}) were prepared, where the individual Pt NP is encapsulated by the mesoporous silica layer. The Pt{at}mSiO{sub 2} catalysts showed promising catalytic activity in high temperature CO oxidation. The design of catalytic structures with tunable parameters by rational synthetic methods presents a major advance in the field of catalyst synthesis, which would lead to uncover the structure-function relationships in heterogeneous catalytic reactions.

Somorjai, G.A.

2009-09-14T23:59:59.000Z

82

Synthesis, adsorption and regeneration of nanoporous silica aerogel and silica aerogel-activated carbon composites  

Science Journals Connector (OSTI)

Abstract Usage of aerogels as an adsorbent has become more widespread because of its specifications such as high porosity and specific surface. Nanometer silica aerogel and silica aerogel-activated carbon composites were synthesized using a water glass precursor by ambient pressure drying method. Then, the adsorption capacity of synthesized adsorbents was studied in terms of benzene and ethyl benzene adsorption by chromatography method for continuous and batch testing. Results showed that silica aerogel and silica aerogel-activated carbon composites had high tendency for benzene and ethyl benzene adsorption. Silica aerogel showed maximum adsorption capacity of 2.3 g g?1 and 0.7 g g?1 in static adsorption of benzene and ethyl benzene respectively. Also, in dynamic adsorption of benzene and ethyl benzene, silica aerogel had maximum equilibrium adsorption capacity of 0.954 g g?1 and 0.219 g g?1 respectively. Minimum equilibrium adsorption capacity in benzene and ethyl benzene static adsorption was related to activated carbon with 0.7 g g?1 and silica aerogel–2 wt% activated carbon with 0.25 g g?1 respectively. After adsorption process, silica aerogel and silica aerogel–0.5 wt% activated carbon composite were regenerated by solvent extraction–thermal treatment method and, after at least 15 adsorption/desorption cycles, their adsorption capacity became fixed.

Akbar Mohammadi; Jafarsadegh Moghaddas

2014-01-01T23:59:59.000Z

83

Properties and Structures of Sulfonated Syndiotactic Polystyrene Aerogel and Syndiotactic Polystyrene/Silica Hybrid Aerogel.  

E-Print Network [OSTI]

??This study focuses on hybrid aerogels of syndiotactic polystyrene (sPS) and silica where silica concentration is varied and silica condensation conditions are varied to produce… (more)

Zhang, Huan

2014-01-01T23:59:59.000Z

84

Click Synthesis of Monolithic Silicon Carbide Aerogels from Polyacrylonitrile-Coated 3D Silica Networks  

Science Journals Connector (OSTI)

Monolithic highly porous (70% v/v) SiC aerogels are synthesized carbothermally from X-PAN-SiO2, i.e., monolithic silica aerogels are prepared and coated in one pot with a conformal poly acrylonitrile coating via a surface-initiated free radical process. ... Conformal PAN coatings would be obtained with other surface-confined initiators, including monodentate ones. ... An aerogel-like composite material was synthesized by casting a conformal 4-6 nm diisocyanate-derived polymer coating on the bird-nest like skeletal framework of mesoporous vanadia consisting of entangled 100-200 nm long, 30-40 nm thick worm-like objects. ...

Nicholas Leventis; Anand Sadekar; Naveen Chandrasekaran; Chariklia Sotiriou-Leventis

2010-03-23T23:59:59.000Z

85

Vibrational amplitudes in vitreous silica  

Science Journals Connector (OSTI)

A model structure of vitreous silica, for which the vibrational frequencies and eigenmodes were calculated from first principles, is used to investigate vibrational amplitudes. Calculated mean-square displacements for oxygen and silicon atoms are obtained as a function of temperature. The square displacement tensors of oxygen atoms show a marked anisotropic character, which is related to the local geometry. The displacements of oxygen atoms along the three principal directions can be associated to distinct parts of the vibrational spectrum, as evidenced by their thermal dependence. These anisotropic effects directly affect the elastic and the static structure factors, which are sensitive to the correlation between displacements of different atoms along their connecting direction. This description shows that the observed widths for Si-O and O-O correlations mainly derive from atomic vibrations rather than from structural disorder. Anisotropic correlations between different atoms are shown to be important up to a distance of 4 Å, i.e., involving atoms that belong to corner-sharing tetrahedra. The scattering functions, calculated at finite temperature and in the harmonic approximation, show good agreement with experiment. In particular, the comparison between the static and the elastic structure factors yields a characterization of the correlated displacements in accord with experimental observations. The static structure factor is significantly affected by anisotropic correlations, but shows only a weak dependence on temperature between 0 and 300 K.

Alfredo Pasquarello

2000-02-01T23:59:59.000Z

86

Multimodality Imaging with Silica-Based Targeted Nanoparticle Platforms  

SciTech Connect (OSTI)

Objectives: To synthesize and characterize a C-Dot silica-based nanoparticle containing 'clickable' groups for the subsequent attachment of targeting moieties (e.g., peptides) and multiple contrast agents (e.g., radionuclides with high specific activity) [1,2]. These new constructs will be tested in suitable tumor models in vitro and in vivo to ensure maintenance of target-specificity and high specific activity. Methods: Cy5 dye molecules are cross-linked to a silica precursor which is reacted to form a dye-rich core particle. This core is then encapsulated in a layer of pure silica to create the core-shell C-Dot (Figure 1) [2]. A 'click' chemistry approach has been used to functionalize the silica shell with radionuclides conferring high contrast and specific activity (e.g. 64Cu and 89Zr) and peptides for tumor targeting (e.g. cRGD and octreotate) [3]. Based on the selective Diels-Alder reaction between tetrazine and norbornene, the reaction is bioorthogonal, highyielding, rapid, and water-compatible. This radiolabeling approach has already been employed successfully with both short peptides (e.g. octreotate) and antibodies (e.g. trastuzumab) as model systems for the ultimate labeling of the nanoparticles [1]. Results: PEGylated C-Dots with a Cy5 core and labeled with tetrazine have been synthesized (d = 55 nm, zeta potential = -3 mV) reliably and reproducibly and have been shown to be stable under physiological conditions for up to 1 month. Characterization of the nanoparticles revealed that the immobilized Cy5 dye within the C-Dots exhibited fluorescence intensities over twice that of the fluorophore alone. The nanoparticles were successfully radiolabeled with Cu-64. Efforts toward the conjugation of targeting peptides (e.g. cRGD) are underway. In vitro stability, specificity, and uptake studies as well as in vivo imaging and biodistribution investigations will be presented. Conclusions: C-Dot silica-based nanoparticles offer a robust, versatile, and multi-functional platform to enhance in vivo detection sensitivity and non-invasively assay receptor expression/status of tumor cellular targets, including those of low abundance, using nuclear-NIR fluorescence imaging approaches [2]. Improvements in molecular diagnostics, refined by the availability of nanotechnology platforms, will be a key determinant in driving early-stage disease detection and prevention, ultimately leading to decreases in mortality.

Jason S. Lewis

2012-04-09T23:59:59.000Z

87

First-principles calculations of defects in oxygen-deficient silica exposed to hydrogen  

Science Journals Connector (OSTI)

Hydrogen-related defects and oxygen vacancies in silica are analyzed using first-principles density-functional calculations. Energetics, structures, charge-state levels, and hyperfine parameters are determined. These calculations identify the hydrogen bridge related to the E4? center as the defect responsible for the stress-induced leakage current, a forerunner of dielectric breakdown of gate oxides in transistors.

Peter E. Blöchl

2000-09-01T23:59:59.000Z

88

Fluoroalkylsilane versus alkylsilane as hydrophobic agents for silica and silicates  

Science Journals Connector (OSTI)

Hydrophobic powders were obtained via surface modification of silica or magnesium silicate with selected silanes. A modified precipitation method, carried out in an emulsion system, was used for monodisperse silica synthesis, while magnesium silicate ...

Damian Ambrozewicz; Filip Ciesielczyk; Magdalena Nowacka; Joanna Karasiewicz; Adam Piasecki; Hieronim Maciejewski; Teofil Jesionowski

2013-01-01T23:59:59.000Z

89

Electrostatically Tuned Interactions in Silica Microsphere-Polystyrene Nanoparticle Mixtures  

E-Print Network [OSTI]

Electrostatically Tuned Interactions in Silica Microsphere-Polystyrene Nanoparticle Mixtures Angel: July 26, 2005 We explore the generality of nanoparticle haloing1 as a novel colloidal stabilization mechanism in binary mixtures of silica microspheres and polystyrene nanoparticles. By selectively tuning

Lewis, Jennifer

90

Nano-Macro Correlation of Nano-Silica Concrete  

Science Journals Connector (OSTI)

Concrete mixes using progressively finer size nano-silica particles (7–150nm) were prepared to study the effect of nano-size pozzolans (nano-silica). Conventional compression tests demonstrated progressively high...

Joan Schoepfer; Arup Maji

2013-01-01T23:59:59.000Z

91

Silane Modification of Glass and Silica Surfaces to Obtain Equally...  

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

Silane Modification of Glass and Silica Surfaces to Obtain Equally Oil-Wet Surfaces in Glass-Covered Silicon Micromodel Silane Modification of Glass and Silica Surfaces to Obtain...

92

Nanoporous polymer electrolyte  

DOE Patents [OSTI]

A nanoporous polymer electrolyte and methods for making the polymer electrolyte are disclosed. The polymer electrolyte comprises a crosslinked self-assembly of a polymerizable salt surfactant, wherein the crosslinked self-assembly includes nanopores and wherein the crosslinked self-assembly has a conductivity of at least 1.0.times.10.sup.-6 S/cm at 25.degree. C. The method of making a polymer electrolyte comprises providing a polymerizable salt surfactant. The method further comprises crosslinking the polymerizable salt surfactant to form a nanoporous polymer electrolyte.

Elliott, Brian (Wheat Ridge, CO); Nguyen, Vinh (Wheat Ridge, CO)

2012-04-24T23:59:59.000Z

93

Non-supercritically dried silica–silica composite aerogel and its possible application for confining simulated nuclear wastes  

Science Journals Connector (OSTI)

The simpler non-supercritical drying approach has been used for the first time for the preparation of silica–silica composite aerogels (CA) and the efficiency of the process being demonstrated by testing the u...

P. R. Aravind; P. Shajesh; P. Mukundan…

2008-05-01T23:59:59.000Z

94

Silica Sol as a Nanoglue: Flexible Synthesis of Composite Aerogels  

Science Journals Connector (OSTI)

...Vulcan carbon–silica aerogel composites are not conductive...low-reflectivity monoliths and coatings. Although light from...through a pure silica aerogel, no light passes through...low-reflectivity monoliths and coatings. Although light from...through a pure silica aerogel, no light passes through...

Catherine A. Morris; Michele L. Anderson; Rhonda M. Stroud; Celia I. Merzbacher; Debra R. Rolison

1999-04-23T23:59:59.000Z

95

Chemistry of Silica in Cerro Prieto Brines  

E-Print Network [OSTI]

1975). When operated without sludge r e c i r c u l a t i ot o c o l l o i d a l silica. sludge accumulation there. thel a t i o n of part of the sludge coming out of The l a r g

Weres, O.

2010-01-01T23:59:59.000Z

96

Chemistry of Silica in Cerro Prieto Brines  

E-Print Network [OSTI]

1975). When operated without sludge r e c i r c u l a t i ot o c o l l o i d a l silica. sludge accumulation there. thel a t i o n of part of the sludge coming out of The l a r g

Weres, Oleh

2012-01-01T23:59:59.000Z

97

Origin of Libyan Desert Silica-Glass  

Science Journals Connector (OSTI)

... of germanium, using a modified method of Schneider and Sandell4, in Libyan Desert silica-glass, Libyan Desert sandstone, a Libyan Desert quartzite, two Libyan Desert sands, Aouelloul crater ... Desert sandstone, a Libyan Desert quartzite, two Libyan Desert sands, Aouelloul crater 'impactite' glass, two obsidians, the average for tektites from eleven different localities, including all known ...

ALVIN J. COHEN

1959-05-30T23:59:59.000Z

98

Monitoring polymer properties in production wells of Chateaurenard oilfield  

SciTech Connect (OSTI)

A polymer flooding test was conducted in the Chateaurenard field (France) from 1985 to 1989. The test was run on a ten-acre inverted five-spot. A total of 240,000 m{sup 3} of partially hydrolyzed polyacrylamide at a concentration of 1000 ppm was injected followed by an equal volume of solution but at a tapered concentration. A strong response in oil recovery for three of the four producers was observed. This paper reports on an original methodology that was designed for sampling and analyzing the polymer in the effluents of the producing wells. Concentrations and main characteristics of produced polyacrylamide were determined versus injected volume. No degradation of the polymer was detected. A molecular weight fractionation during polymer slug propagation into the reservoir due to adsorption/retention chromatography was observed. The low-polymer concentration of the effluents could be explained by a strong retention of the polymer in the low permeability zones of the reservoir.

Putz, A.G. (Elf Aquitaine, Avenue Larribau, Pau (FR)); Lecourtier, J. (Inst. Francais du Petrole, Avenue Bois-Preau, 92500 Rueil-Malmaison (FR))

1991-01-01T23:59:59.000Z

99

Bulk Heterojunction Polymer Solar Cells  

Science Journals Connector (OSTI)

Recent developments on bulk-heterojunction polymer photovoltaic diodes will be presented, focusing on the mechanism of charge generation, low bandgap polymers for increased photon...

Janssen, René

100

Interaction of silica nano-particles with a flat silica surface through neutron reflectometry  

SciTech Connect (OSTI)

Neutron reflectometry (NR) was employed to study the interaction of nanosized silica particles with a flat silica surface in aqueous solutions. Unlike other experimental tools that are used to study surface interactions, NR can provide information on the particle density profile in the solution near the interface. Two types of silica particles (25 and 100 nm) were suspended in aqueous solutions of varying ionic strength. Theoretical calculations of the surface interaction potential between a particle and a flat silica surface using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory were compared to the experimental data. The theory predicts that the potential energy is highly dependent on the ionic strength. In high ionic strength solutions, NR reveals a high concentration of particles near the flat silica surface. Under the same conditions, theoretical calculations show an attractive force between a particle and a flat surface. For low ionic strength solutions, the particle concentration near the surface obtained from NR is the same as the bulk concentration, while depletion of particles near the surface is expected because of the repulsion predicted by the DLVO theory.

Chung, Eunhyea [Georgia Institute of Technology; Yiacoumi, Sotira [Georgia Institute of Technology; Halbert, Candice E [ORNL; Ankner, John Francis [ORNL; Wang, Wei [ORNL; Tsouris, Costas [ORNL

2012-01-01T23:59:59.000Z

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


101

Radioluminescent polymer lights  

SciTech Connect (OSTI)

The preparation of radioluminescent light sources where the tritium is located on the aryl-ring in a polymer has been demonstrated with deuterium/tritium substitution. This report discusses tests, results, and future applications of radioluminescent polymers. 10 refs. (FI)

Jensen, G.A.; Nelson, D.A.; Molton, P.M.

1990-09-01T23:59:59.000Z

102

Cryogenic properties of optomechanical silica microcavities  

E-Print Network [OSTI]

We present the optical and mechanical properties of high-Q fused silica microtoroidal resonators at cryogenic temperatures (down to 1.6 K). A thermally induced optical multistability is observed and theoretically described; it serves to characterize quantitatively the static heating induced by light absorption. Moreover the influence of structural defect states in glass on the toroid mechanical properties is observed and the resulting implications of cavity optomechanical systems on the study of mechanical dissipation discussed.

Olivier Arcizet; Rémi Rivière; Albert Schliesser; Tobias J. Kippenberg

2009-01-09T23:59:59.000Z

103

Acid strength of silica-supported oxide catalysts studied by microcalorimetric measurements of pyridine adsorption  

SciTech Connect (OSTI)

Microcalorimetric measurements of the differential heat of pyridine adsorption were used to probe the distribution of acid strength on a series of silica-supported oxide catalysts. Depositing oxides of the following cations onto silica increased the acid strength of the catalyst: Ga{sup 3{plus}}, Zn{sup 2{plus}}, Al{sup 3{plus}}, Fe{sup 3{plus}}, Fe{sup 2{plus}}, Mg{sup 2{plus}}, and Sc{sup 3{plus}}. The acid strength distribution curves for the supported oxide samples showed either two or three regions of constant heat of adsorption while silica had an energetically homogeneous surface. The Ga, Al, and Sc samples were found to have both Bronsted and Lewis acidity while the remaining samples showed only Lewis acidity. Incremental adsorption of pyridine indicated that the initial region of highest heat corresponds to strong Lewis acidity while intermediate heats seemed to be due to weaker Lewis acid sites or a combination of Lewis and Bronsted acid sites. The final region of lowest heat was due to H-bonded pyridine on silica. Estimates of the entropies of adsorption were determined, providing information about the mobility of the adsorbed pyridine molecules. The initial differential heat of adsorption increases proportionally to the Sanderson electronegativity of the added oxide.

Cardona-Martinez, N.; Dumesic, J.A. (Univ. of Wisconsin, Madison (USA))

1991-02-01T23:59:59.000Z

104

Novel silica-based ion exchange resin  

SciTech Connect (OSTI)

Eichrom`s highly successful Diphonixo resin resembles a conventional ion exchange resin in its use of sulfonic acid ligands on a styrene- divinylbenzene matrix. Diphonix resin exhibits rapid exchange kinetics that allow economical operation of ion exchange systems. Unlike conventional resins, Diphonix resin contains chelating ligands that are diphosphonic acid groups that recognize and remove the targeted metals and reject the more common elements such as sodium, calcium and magnesium. This latter property makes Diphonix ideal for many industrial scale applications, including those involving waste treatment. For treatment of low-level, transuranic (TRU) and high- level radioactive wastes, Diphonix`s polystyrene backbone hinders its application due to radiolytic stability of the carbon-hydrogen bonds and lack of compatibility with expected vitrification schemes. Polystyrene-based Diphonix is approximately 60% carbon- hydrogen. In response to an identified need within the Department of Energy for a resin with the positive attributes of Diphonix that also exhibits greater radiolytic stability and final waste form compatibility, Eichrom has successfully developed a new, silica-based resin version of Diphonix. Target application for this new resin is for use in environmental restoration and waste management situations involving the processing of low-level, transuranic and high-level radioactive wastes. The resin can also be used for processing liquid mixed waste (waste that contains low level radioactivity and hazardous constituents) including mixed wastes contaminated with organic compounds. Silica-based Diphonix is only 10% carbon-hydrogen, with the bulk of the matrix silica.

NONE

1997-11-01T23:59:59.000Z

105

GLASSY STATES OF ADSORBED FLEXIBLE POLYMERS AND SPREAD POLYMER "MONOLAYERS"  

E-Print Network [OSTI]

1269 GLASSY STATES OF ADSORBED FLEXIBLE POLYMERS AND SPREAD POLYMER "MONOLAYERS" K. KREMER* Exxon mechanism for the dynamics of irreversibly adsorbed polymers. We argue that glass-like states can exist near of polymer adsorbed ' ' and the thickness of the adsorbed layer 2-7. While the results of the different

Paris-Sud XI, Université de

106

Silica powders for powder evacuated thermal insulating panel and method  

DOE Patents [OSTI]

A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2/ g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

1996-01-01T23:59:59.000Z

107

Silica powders for powder evacuated thermal insulating panel and method  

DOE Patents [OSTI]

A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm{sup 3} and an external surface area in the range of about 90 to 600 m{sup 2}/g is described. The silica powders are prepared by reacting a tetraalkyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders. 2 figs.

Harris, M.T.; Basaran, O.A.; Kollie, T.G.; Weaver, F.J.

1996-01-02T23:59:59.000Z

108

Silica powders for powder evacuated thermal insulating panel and method  

DOE Patents [OSTI]

A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2/ g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

1995-01-01T23:59:59.000Z

109

Silica powders for powder evacuated thermal insulating panel and method  

DOE Patents [OSTI]

A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm.sup.3 and an external surface area in the range of about 90 to 600 m.sup.2 /g is described. The silica powders are prepared by reacting a tetraakyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders.

Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Kollie, Thomas G. (Oak Ridge, TN); Weaver, Fred J. (Knoxville, TN)

1994-01-01T23:59:59.000Z

110

Experimental stress–strain analysis of tapered silica optical fibers with nanofiber waist  

SciTech Connect (OSTI)

We experimentally determine tensile force–elongation diagrams of tapered optical fibers with a nanofiber waist. The tapered optical fibers are produced from standard silica optical fibers using a heat and pull process. Both, the force–elongation data and scanning electron microscope images of the rupture points indicate a brittle material. Despite the small waist radii of only a few hundred nanometers, our experimental data can be fully explained by a nonlinear stress–strain model that relies on material properties of macroscopic silica optical fibers. This is an important asset when it comes to designing miniaturized optical elements as one can rely on the well-founded material characteristics of standard optical fibers. Based on this understanding, we demonstrate a simple and non-destructive technique that allows us to determine the waist radius of the tapered optical fiber. We find excellent agreement with independent scanning electron microscope measurements of the waist radius.

Holleis, S.; Hoinkes, T.; Wuttke, C.; Schneeweiss, P.; Rauschenbeutel, A. [Vienna Center for Quantum Science and Technology, TU Wien—Atominstitut, Stadionallee 2, 1020 Vienna (Austria)

2014-04-21T23:59:59.000Z

111

Defect Migration and Recombination in Nanoindentation of Silica...  

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

Defect Migration and Recombination in Nanoindentation of Silica Glass Authors: Nomura, K., Chen, Y., Kalia, R.K., Nakano, A., Vashishta, P. Deformation, plasticity, and flow in...

112

Characterisation of Dust Particles Trapped in Silica Aerogels.  

E-Print Network [OSTI]

?? This thesis involves the study of dust particles trapped in silica aerogel for fusion dust diagnostics purpose. The low velocity impact experiments are done… (more)

Liu, Bing

2011-01-01T23:59:59.000Z

113

Feasibility of using silica aerogel as insulation for buildings.  

E-Print Network [OSTI]

?? For recent years, silica aerogel has attracted great attention and been extensively used in different technical fields owning to its remarkable properties in optics,… (more)

Huang, Lang

2012-01-01T23:59:59.000Z

114

Thermosetting Polymer-Matrix Composites for Strucutral Repair Applications  

SciTech Connect (OSTI)

Several classes of thermosetting polymer matrix composites were evaluated for use in structural repair applications. Initial work involved the characterization and evaluation of woven carbon fiber/epoxy matrix composites for structural pipeline repair. Cyanate ester resins were evaluated as a replacement for epoxy in composites for high-temperature pipe repair applications, and as the basis for adhesives for resin infusion repair of high-temperature composite materials. Carbon fiber/cyanate ester matrix composites and fumed silica/cyanate ester nanocomposites were evaluated for their thermal, mechanical, viscoelastic, and rheological properties as they relate to their structure, chemistry, and processing characteristics. The bisphenol E cyanate ester under investigation possesses a high glass transition temperature, excellent mechanical properties, and unique ambient temperature processability. The incorporate of fumed silica served to enhance the mechanical and rheological properties of the polymer and reduce thermal expansion without sacrificing glass transition or drastically altering curing kinetics. Characterization of the composites included dynamic mechanical analysis, thermomechanical analysis, differential scanning calorimetry, thermogravimetric analysis, rheological and rheokinetic evaluation, and transmission electron microscopy.

William Kirby Goertzen

2007-12-01T23:59:59.000Z

115

Streamlined life cycle assessment of transparent silica aerogel made by supercritical drying  

Science Journals Connector (OSTI)

When developing sustainable building fabric technologies, it is essential that the energy use and CO2 burden arising from manufacture does not outweigh the respective in-use savings. This study investigates this paradigm by carrying out a streamlined life cycle assessment (LCA) of silica aerogel. This unique, nanoporous translucent insulation material has the lowest thermal conductivity of any solid, retaining up to four times as much heat as conventional insulation, whilst being highly transparent to light and solar radiation. Monolithic silica aerogel has been cited as the ‘holy grail’ of future glazing technology. Alternatively, translucent granular aerogel is now being produced on a commercial scale. In each case, many solvents are used in production, often accompanied by intensive drying processes, which may consume large amounts of energy and CO2. To date, there has been no peer-reviewed LCA of this material conducted to the ISO 14000 standard. Primary data for this ‘cradle-to-factory gate’ LCA is collected for silica aerogel made by low and high temperature supercritical drying. In both cases, the mass of raw materials and electricity usage for each process is monitored to determine the total energy use and CO2 burden. Findings are compared against the predicted operational savings arising from retrofitting translucent silica aerogel to a single glazed window to upgrade its thermal performance. Results should be treated as a conservative estimate as the aerogel is produced in a laboratory, which has not been developed for mass manufacture or refined to reduce its environmental impact. Furthermore, the samples are small and assumptions to upscale the manufacturing volume occur without major changes to production steps or equipment used. Despite this, parity between the CO2 burden and CO2 savings is achieved in less than 2 years, indicating that silica aerogel can provide a measurable environmental benefit.

Mark Dowson; Michael Grogan; Tim Birks; David Harrison; Salmaan Craig

2012-01-01T23:59:59.000Z

116

Polymer/Clay Nanocomposites as Barrier Materials Used for VOC Removal.  

E-Print Network [OSTI]

??The objective of this study was to determine if the method of incorporation of a silicate layered nanoclay into a polymer matrix can affect the… (more)

Herrera-Alonso, Jose M

2009-01-01T23:59:59.000Z

117

Heats of Formation of Energetic Oxetane Monomers and Polymers  

SciTech Connect (OSTI)

Energetic oxetane polymers have shown promise as performance-enhancing ingredients in gun and missile propellants. In order to correctly predict the performance of energetic materials containing these polymers, it is important to have accurate, experimentally determined values for the polymer heats of formation ({Delta}H{sub f}). In support of a theoretical study on gun propellant performance, heats of combustion were experimentally determined for a series of oxetane polymers and monomers (see below) using combustion calorimetry, and from these, {Delta}H{sub f} values were calculated. Polymers included BAMO/AMMO, BAMO/NMMO (polyol and TPE), and BNMO/NMMO mixtures. In order to calculate the {Delta}H{sub f} of the polymers from heat of combustion data, a number of assumptions were made regarding the polymer structure and molecular weight. A comparison of the {Delta}H{sub f} values for the monomers and polymers were made, and these values were compared to heats of formation measured elsewhere.

Schmidt, R D; Manser, G E

2001-03-21T23:59:59.000Z

118

Sulfonated polyphenylene polymers  

DOE Patents [OSTI]

Improved sulfonated polyphenylene compositions, improved polymer electrolyte membranes and nanocomposites formed there from for use in fuel cells are described herein. The improved compositions, membranes and nanocomposites formed there from overcome limitations of Nafion.RTM. membranes.

Cornelius, Christopher J. (Albuquerque, NM); Fujimoto, Cy H. (Albuquerque, NM); Hickner, Michael A. (Albuquerque, NM)

2007-11-27T23:59:59.000Z

119

Fibrous composites comprising carbon nanotubes and silica  

DOE Patents [OSTI]

Fibrous composite comprising a plurality of carbon nanotubes; and a silica-containing moiety having one of the structures: (SiO).sub.3Si--(CH.sub.2).sub.n--NR.sub.1R.sub.2) or (SiO).sub.3Si--(CH.sub.2).sub.n--NCO; where n is from 1 to 6, and R.sub.1 and R.sub.2 are each independently H, CH.sub.3, or C.sub.2H.sub.5.

Peng, Huisheng (Shanghai, CN); Zhu, Yuntian Theodore (Cary, NC); Peterson, Dean E. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)

2011-10-11T23:59:59.000Z

120

Cryogenic properties of optomechanical silica microcavities  

Science Journals Connector (OSTI)

We report the study of the optical and mechanical properties of high-Q fused silica microtoroidal resonators at cryogenic temperatures (down to 1.6 K). A thermally induced optical multistability is observed and theoretically described, originating from the reverse thermally induced optical frequency shift. Moreover the influence of structural defect states (two level fluctuators) on their mechanical properties is observed and probed at an unprecedentedly achieved low phonon number. The resulting implications for cavity optomechanics and studies of mechanical decoherence are also discussed.

O. Arcizet; R. Rivière; A. Schliesser; G. Anetsberger; T. J. Kippenberg

2009-08-12T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Suspended bridge-like silica 2×2 beam splitter on silicon  

Science Journals Connector (OSTI)

We report a successful experimental realization of a 2×2 suspended silica splitter integrated on a silicon substrate. The silica splitter was photo-lithographically patterned,...

Zhang, Xiaomin; Armani, Andrea M

2011-01-01T23:59:59.000Z

122

Silica Bridge Impact on Hollow-Core Bragg Fiber Transmission Properties  

Science Journals Connector (OSTI)

The silica bridges impact on the hollow-core Bragg fiber guiding properties is investigated. Results demonstrate that silica nanosupports are responsible for the surface mode...

Poli, Federica; Foroni, Matteo; Giovanelli, Daniele; Cucinotta, Annamaria; Selleri, Stefano; Jensen, Jesper Bo; Lægsgaard, Jesper; Bjarklev, Anders; Vienne, Guillaume; Jakobsen, Christian; Broeng, Jes

123

Preparation of superhydrophobic and transparent micro-nano hybrid coatings from polymethylhydroxysiloxane and silica ormosil aerogels  

Science Journals Connector (OSTI)

Superhydrophobic and transparent polymethylhydroxysiloxane (PMHOS)/silica ormosil aerogel hybrids were prepared successfully by mixing of PMHOS with various weight percentages of silica ormosil aerogels (as sy...

Saravanan Nagappan; Jin Joo Park; Sung Soo Park; Chang-Sik Ha

2014-12-01T23:59:59.000Z

124

Dye-Doped Silica Nanoparticle Labels/Protein Microarray for Detection...  

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

Dye-Doped Silica Nanoparticle LabelsProtein Microarray for Detection of Protein Biomarkers. Dye-Doped Silica Nanoparticle LabelsProtein Microarray for Detection of Protein...

125

Single molecule studies of meso/macro porous silica materials and gradient films.  

E-Print Network [OSTI]

??The preparation of mesoporous/macroporous silica materials and polarity gradient thin film are introduced in this thesis. These porous silica materials and gradient materials have the… (more)

Ye, Fangmao

2009-01-01T23:59:59.000Z

126

Biological Applications and Transmission Electron Microscopy Investigations of Mesoporous Silica Nanoparticles  

SciTech Connect (OSTI)

The research presented and discussed within involves the development of novel biological applications of mesoporous silica nanoparticles (MSN) and an investigation of mesoporous material by transmission electron microscopy (TEM). Mesoporous silica nanoparticles organically functionalized shown to undergo endocytosis in cancer cells and drug release from the pores was controlled intracellularly and intercellularly. Transmission electron microscopy investigations demonstrated the variety of morphologies produced in this field of mesoporous silica nanomaterial synthesis. A series of room-temperature ionic liquid (RTIL) containing mesoporous silica nanoparticle (MSN) materials with various particle morphologies, including spheres, ellipsoids, rods, and tubes, were synthesized. By changing the RTIL template, the pore morphology was tuned from the MCM-41 type of hexagonal mesopores to rotational moire type of helical channels, and to wormhole-like porous structures. These materials were used as controlled release delivery nanodevices to deliver antibacterial ionic liquids against Escherichia coli K12. The involvement of a specific organosiloxane function group, covalently attached to the exterior of fluorescein doped mesoporous silica nanoparticles (FITC-MSN), on the degree and kinetics of endocytosis in cancer and plant cells was investigated. The kinetics of endocystosis of TEG coated FITC-MSN is significantly quicker than FITC-MSN as determined by flow cytometry experiments. The fluorescence confocal microscopy investigation showed the endocytosis of TEG coated-FITC MSN triethylene glycol grafted fluorescein doped MSN (TEG coated-FITC MSN) into both KeLa cells and Tobacco root protoplasts. Once the synthesis of a controlled-release delivery system based on MCM-41-type mesoporous silica nanorods capped by disulfide bonds with superparamagnetic iron oxide nanoparticles was completed. The material was characterized by general methods and the dosage and kinetics of the antioxidant dependent release was measured. Finally, the biological interaction of the material was determined along with TEM measurements. An electron investigation proved that the pore openings of the MSN were indeed blocked by the Fe{sub 3}O{sub 4} nanoparticles. The biological interaction investigation demonstrated Fe{sub 3}O{sub 4}-capped MSN endocytosis into HeLa cells. Not only does the material enter the cells through endocytosis, but it seems that fluorescein was released from the pores most probably caused by disulfide bond reducing molecules, antioxidants. In addition to endocytosis and release, the Fe{sub 3}O{sub 4}-capped MSN propelled the cells across a cuvette upon induction of a magnet force. Finally, an important aspect of materials characterization is transmission electron microscopy. A TEM investigation demonstrated that incorporating different functional groups during the synthesis (co-condensation) changed the particle and pore morphologies.

Brian G. Trewyn

2006-05-01T23:59:59.000Z

127

Controlled morphogenesis of amorphous silica and its relevance to biosilicification  

Science Journals Connector (OSTI)

...to silica in areas where silica...component of all plasma membranes...in a flow air atmosphere. 29Si MAS NMR...spectrometer at 79.49 MHz under single...Specific surface areas were calculated...particles at a large scale. Table...also show a large increase at...BET surface area and pore volume...

Jia-Yuan Shi; Qi-Zhi Yao; Xi-Ming Li; Gen-Tao Zhou; Sheng-Quan Fu

128

Community Geothermal Technology Program: Silica bronze project. Final report  

SciTech Connect (OSTI)

Objective was to incorporate waste silica from the HGP-A geothermal well in Pohoiki with other refractory materials for investment casting of bronze sculpture. The best composition for casting is about 50% silica, 25% red cinders, and 25% brick dust; remaining ingredient is a binder, such as plaster and water.

Bianchini, H.

1989-10-01T23:59:59.000Z

129

Simulations Reveal That Earth's Silica Is Predominantly Superficial - NERSC  

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

Reveal Reveal Earth's Silica Is Predominantly Superficial Simulations Reveal Earth's Silica Is Predominantly Superficial May 24, 2010 Silica is one of the most common minerals on Earth. Not only does it make up two-thirds of our planet's crust, it is also used to create a variety of materials from glass to ceramics, computer chips and fiber optic cables. Yet new quantum mechanics results generated by a team of physicists from Ohio State University (OSU) show that this mineral only populates our planet superficially-in other words, silica is relatively uncommon deep within the Earth. Cross-section of the Earth Using several of the largest supercomputers in the nation, including the National Energy Research Scientific Computing Center's (NERSC) Cray XT4 "Franklin" system, the team simulated the behavior of silica in

130

Mesoporous Silica Nanomaterials for Applications in Catalysis, Sensing, Drug Delivery and Gene Transfection  

SciTech Connect (OSTI)

The central theme of this dissertation is represented by the versatility of mesoporous silica nanomaterials in various applications such as catalysis and bio-applications, with main focus on biological applications of Mesoporous Silica Nanospheres (MSN). The metamorphosis that we impose to these materials from catalysis to sensing and to drug and gene delivery is detailed in this dissertation. First, we developed a synthetic method that can fine tune the amount of chemically accessible organic functional groups on the pores surface of MSN by exploiting electrostatic and size matching between the cationic alkylammonium head group of the cetyltrimethylammonium bromide (CTAB) surfactant and various anionic organoalkoxysilane precursors at the micelle-water interface in a base-catalyzed condensation reaction of silicate. Aiming nature imitation, we demonstrated the catalytic abilities of the MSNs, We utilized an ethylenediamine functional group for chelating Cu{sup 2+} as a catalytic functional group anchored inside the mesopores. Thus, a polyalkynylene-based conducting polymer (molecular wire) was synthesized within the Cu-functionalized MSNs silica catalyst. For sensing applications, we have synthesized a poly(lactic acid) coated mesoporous silica nanosphere (PLA-MSN) material that serves as a fluorescence sensor system for detection of amino-containing neurotransmitters in neutral aqueous buffer. We exploited the mesoporosity of MSNs for encapsulating pharmaceutical drugs. We examined bio-friendly capping molecules such as polyamidoamine dendrimers of generations G2 to G4, to prevent the drug leaching. Next, the drug delivery system employed MSNs loaded with Doxorubicin, an anticancer drug. The results demonstrated that these nano-Trojan horses have ability to deliver Doxorubicin to cancer cells and induce their death. Finally, to demonstrate the potential of MSN as an universal cellular transmembrane nanovehicle, we anchored positively charged dendrimers on the surface of MSN and utilize them to complex cationic DNA. The p-EGFP-CI gene-coated MSN nanocomposite was able to transfect cancer cell lines, such as human HeLa and CHO cancer cell lines. The gene carrier ability of MSNs was further proved by transfecting primary cells and cotransfecting of two different genes in cancer cell lines. In sum, MSN are versatile partners in several types of applications.

Daniela Rodica Radu

2005-12-19T23:59:59.000Z

131

Robust Polymer Composite Membranes for Hydrogen Separation |...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Robust Polymer Composite Membranes for Hydrogen Separation Robust Polymer Composite Membranes for Hydrogen Separation polymercompositemembranes.pdf More Documents & Publications...

132

Pitch of a polymer cholesteric  

Science Journals Connector (OSTI)

Pitch of a polymer cholesteric ... We report measurements of the cholesteric pitch and twist elastic constant (K22) in monodisperse suspensions of the rodlike virus filamentous bacteriophage fd. ... Cholesteric Pitch of Lyotropic Polymer Liquid Crystals ...

Theo. Odijk

1987-01-01T23:59:59.000Z

133

polymers | OpenEI  

Open Energy Info (EERE)

polymers polymers Dataset Summary Description These data files contain volume, mass, and hardness changes of elastomers and plastics representative exposed to gasoline containing various levels of ethanol. These materials are representative of those used in gasoline fuel storage and dispensing hardware. All values are compared to the original untreated condition. The data sets include results from specimens exposed directly to the fuel liquid and also a set of specimens exposed only to the fuel vapors. Source Mike Kass, Oak Ridge National Laboratory Date Released August 16th, 2012 (2 years ago) Date Updated August 16th, 2012 (2 years ago) Keywords compatibility elastomers ethanol gasoline plastics polymers Data application/vnd.openxmlformats-officedocument.spreadsheetml.sheet icon plastics_dma_results_san.xlsx (xlsx, 4.9 MiB)

134

Solid polymer electrolyte from phosphorylated chitosan  

SciTech Connect (OSTI)

Recently, the need of secondary battery application continues to increase. The secondary battery which using a liquid electrolyte was indicated had some weakness. A solid polymer electrolyte is an alternative electrolytes membrane which developed in order to replace the liquid electrolyte type. In the present study, the effect of phosphorylation on to polymer electrolyte membrane which synthesized from chitosan and lithium perchlorate salts was investigated. The effect of the component’s composition respectively on the properties of polymer electrolyte, was carried out by analyzed of it’s characterization such as functional groups, ion conductivity, and thermal properties. The mechanical properties i.e tensile resistance and the morphology structure of membrane surface were determined. The phosphorylation processing of polymer electrolyte membrane of chitosan and lithium perchlorate was conducted by immersing with phosphoric acid for 2 hours, and then irradiated on a microwave for 60 seconds. The degree of deacetylation of chitosan derived from shrimp shells was obtained around 75.4%. Relative molecular mass of chitosan was obtained by viscometry method is 796,792 g/mol. The ionic conductivity of chitosan membrane was increase from 6.33 × 10{sup ?6} S/cm up to 6.01 × 10{sup ?4} S/cm after adding by 15 % solution of lithium perchlorate. After phosphorylation, the ionic conductivity of phosphorylated lithium chitosan membrane was observed 1.37 × 10{sup ?3} S/cm, while the tensile resistance of 40.2 MPa with a better thermal resistance. On the strength of electrolyte membrane properties, this polymer electrolyte membrane was suggested had one potential used for polymer electrolyte in field of lithium battery applications.

Fauzi, Iqbal, E-mail: arcana@chem.itb.ac.id; Arcana, I Made, E-mail: arcana@chem.itb.ac.id [Inorganic and Physical Chemistry Research Groups, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia)

2014-03-24T23:59:59.000Z

135

Phase behavior of methane hydrate in silica sand  

Science Journals Connector (OSTI)

Abstract Two kinds of silica sand powder with different particle size were used to investigate the phase behavior of methane hydrate bearing sediment. In coarse-grained silica sand, the measured temperature and pressure range was (281.1 to 284.2) K and (5.9 to 7.8) MPa, respectively. In fine-grained silica sand, the measured temperature and pressure range was (281.5 to 289.5) K and (7.3 to 16.0) MPa, respectively. The results show that the effect of coarse-grained silica sand on methane hydrate phase equilibrium can be ignored; however, the effect of fine-grained silica sand on methane hydrate phase equilibrium is significant, which is attributed to the depression of water activity caused by the hydrophilicity and negatively charged characteristic of silica particle as well as the pore capillary pressure. Besides, the analysis of experimental results using the Gibbs–Thomson equation shows that methane hydrate phase equilibrium is related to the pore size distribution of silica sand. Consequently, for the correct application of phase equilibrium data of hydrate bearing sediment, the geological condition and engineering requirement should be taken into consideration in gas production, resource evaluation, etc.

Shi-Cai Sun; Chang-Ling Liu; Yu-Guang Ye; Yu-Feng Liu

2014-01-01T23:59:59.000Z

136

DSM INVESTS IN MEDICAL POLYMERS  

Science Journals Connector (OSTI)

DSM INVESTS IN MEDICAL POLYMERS ... AS PART OF ITS SHIFT toward the specialty materials business, DSM will acquire Polymer Technology Group (PTG), a privately held maker of biomedical polymers. ... DSM isn’t disclosing the purchase price other than to say it is about 10 times PTG’s annual earnings. ...

MELODY VOITH

2008-05-05T23:59:59.000Z

137

Studies towards DNA-polymer-silica-iron oxide hybrid nanoparticles as stimulus-responsive MR theranostics.  

E-Print Network [OSTI]

??Early detection and treatment of a disease is a desired goal for medical advancements. The concept of theranostics have been introduced to combine diagnosis and… (more)

Shuldberg, Claudia Meneses

2012-01-01T23:59:59.000Z

138

Studies towards DNA-polymer-silica-iron oxide hybrid nanoparticles as stimulus-responsive MR theranostics  

E-Print Network [OSTI]

Stimulus-Responsive MR Theranostics A Thesis is submitted inTHERANOSTICS ..as Stimulus-Responsive MR Theranostics by Claudia Meneses

Shuldberg, Claudia Meneses

2012-01-01T23:59:59.000Z

139

Luminescent organosilicon polymers and sol-gel synthesis of nano-structured silica  

E-Print Network [OSTI]

T.   M.   High   energy   density   materials.   http://T.   M.   High   energy   density   materials.   http://

Martinez, H. Paul

2011-01-01T23:59:59.000Z

140

Sedimentation of Knotted Polymers  

E-Print Network [OSTI]

We investigate the sedimentation of knotted polymers by means of stochastic rotation dynamics, a molecular dynamics algorithm that takes hydrodynamics fully into account. We show that the sedimentation coefficient s, related to the terminal velocity of the knotted polymers, increases linearly with the average crossing number n_c of the corresponding ideal knot. To the best of our knowledge, this provides the first direct computational confirmation of this relation, postulated on the basis of experiments in "The effect of ionic conditions on the conformations of supercoiled DNA. I. sedimentation analysis" by Rybenkov et al., for the case of sedimentation. Such a relation was previously shown to hold with simulations for knot electrophoresis. We also show that there is an accurate linear dependence of s on the inverse of the radius of gyration R_g^-1, more specifically with the inverse of the R_g component that is perpendicular to the direction along which the polymer sediments. When the polymer sediments in a slab, the walls affect the results appreciably. However, R_g^-1 remains to a good precision linearly dependent on n_c. Therefore, R_g^-1 is a good measure of a knot's complexity.

Joonas Piili; Davide Marenduzzo; Kimmo Kaski; Riku Linna

2012-12-20T23:59:59.000Z

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


141

Polymer brush under strong shear  

Science Journals Connector (OSTI)

End-grafted polymer brush exposed to strong shear solvent flow is studied. Under strong enough shear flow, the shear force is nonlinear with the blob size depending on the shear force and not on the monomer volume fraction ?. We derive the crossover force scale separating the weak and strong shear regime. The velocity profile of the flow, v(z), inside and above the brush is calculated analytically by treating the flow as in a porous medium and solving the Brinkman equation. The solution of the velocity profile is then combined with nonequilibrium Monte Carlo simulation data, which allow a self-consistent determination of the chain end-to-end length and the incline angle of the chain. We derive the scaling form for the chain positions x(n) for the nth monomer and verified by our simulation data. We further obtain analytical expression for x(n) in terms of the effective viscosity of the model.

Pik-Yin Lai and Chee-Yuen Lai

1996-12-01T23:59:59.000Z

142

Gel polymer electrolytes for batteries  

DOE Patents [OSTI]

Nanostructured gel polymer electrolytes that have both high ionic conductivity and high mechanical strength are disclosed. The electrolytes have at least two domains--one domain contains an ionically-conductive gel polymer and the other domain contains a rigid polymer that provides structure for the electrolyte. The domains are formed by block copolymers. The first block provides a polymer matrix that may or may not be conductive on by itself, but that can soak up a liquid electrolyte, thereby making a gel. An exemplary nanostructured gel polymer electrolyte has an ionic conductivity of at least 1.times.10.sup.-4 S cm.sup.-1 at 25.degree. C.

Balsara, Nitash Pervez; Eitouni, Hany Basam; Gur, Ilan; Singh, Mohit; Hudson, William

2014-11-18T23:59:59.000Z

143

Different methods to derive pure silica from agriculture waste  

Science Journals Connector (OSTI)

Rice residues are important natural resources, the management of these residues is a major challenge for environment protection. The use of different techniques to produce silica with minimal mineral contaminants having high Specific Surface Area (SSA) has been investigated. The different methods used depended on treatment of rice hulls with different dilute organic acids and hydrochloric acid, without the risk of using corrosive, toxic and hazardous substances in the burning process. Different powdered silica obtained are characterised by particle size distribution, crystallographic structure, BET SSA and chemical analysis. X-ray Diffraction patterns revealed the amorphous nature of silica. The major impurities of silica produced from rice hulls were Na, K and Ca salts.

Azza El-Maghraby; Heba A. El-Deeb

2012-01-01T23:59:59.000Z

144

Operating Experience Level 3, Dangers of Respirable Silica  

Broader source: Energy.gov [DOE]

This Operating Experience Level 3 (OE-3) document provides information on a safety concern related to recurring worker exposure to dust containing crystalline silica at Department of Energy (DOE) sites.

145

Electrospinning of silica nanofibers: characterization and application to biosensing  

E-Print Network [OSTI]

; and the pore size is around several nanometers to a micrometer wide. In this work, the relationship between the diameter of electrospun silica fibers, experimental parameters such as concentration and voltage, and between pore size of the fiber membrane...

Tsou, Pei-Hsiang

2009-06-02T23:59:59.000Z

146

Durability of E-glass fiber reinforced vinyl ester polymer composites with nanoclay in an alkaline environment.  

E-Print Network [OSTI]

??This study was conducted to determine the effect of clay content in the GFRP (glass fiber reinforced polymer) composite samples as they are aged in… (more)

Ravindran, Naveenkamal.

2005-01-01T23:59:59.000Z

147

Solubility properties of siloxane polymers for chemical sensors  

SciTech Connect (OSTI)

This paper discusses the factors governing the sorption of vapors by organic polymers. The principles have been applied in the past for designing and selecting polymers for acoustic wave sensors; however they apply equally well to sorption of vapors by polymers used on optical chemical sensors. A set of solvation parameters (a table is presented for various organic vapors) have been developed that describe the particular solubility properties of individual solute molecules; they are used in linear solvation energy relationships (LSER) that model the sorption process. LSER coefficients are tabulated for five polysiloxanes; so are individual interaction terms for each of the 5 polymers. Dispersion interactions play a major role in determining overall partition coefficients; the log L{sup 16} (gas-liquid partition coefficient of solute on hexadecane) value of vapors are important in determining overall sorption. For the detection of basic vapors such as organophosphates, a hydrogen-bond acidic polymers will be most effective at sorbing them. Currently, fiber optic sensors are being developed where the cladding serves as a sorbent layer to collect and concentrate analyte vapors, which will be detected and identified spectroscopically. These solubility models will be used to design the polymers for the cladding for particular vapors.

Grate, J.W. [Pacific Northwest Lab., Richland, WA (United States); Abraham, M.H. [University College, London (United Kingdom)

1995-05-01T23:59:59.000Z

148

Lightweight polymer concrete composites  

SciTech Connect (OSTI)

Lightweight polymer concrete composites have been developed with excellent insulating properties. The composites consist of lightweight aggregates such as expanded perlites, multicellular glass nodules, or hollow alumina silicate microspheres bound together with unsaturated polyester or epoxy resins. These composites, known as Insulating Polymer Concrete (IPC), have thermal conductivites from 0.09 to 0.19 Btu/h-ft-/sup 0/F. Compressive strengths, dependent upon the aggregates used, range from 1000 to 6000 psi. These materials can be precast or cast-in-place on concrete substrates. Recently, it has been demonstrated that these materials can also be sprayed onto concrete and other substrates. An overlay application of IPC is currently under way as dike insulation at an LNG storage tank facility. The composites have numerous potentials in the construction industry such as insulating building blocks or prefabricated insulating wall panels.

Fontana, J.J.; Steinberg, M.; Reams, W.

1985-08-01T23:59:59.000Z

149

Elegant Way of Strengthening Polymer?Polymer Interface Using Nanoclay  

Science Journals Connector (OSTI)

Elegant Way of Strengthening Polymer?Polymer Interface Using Nanoclay ... In this group, montmorillonite (MMT) nanoclay has been employed in numerous polymer nanocomposite systems because it is environmentally friendly, readily available in large quantities, and its intercalation chemistry has been well studied in comparison with other nanoclays (18-20). ... The detection of this interesting behavior of nanoclays in BIMS rubber has prompted us to initiate a detailed investigation into the tackification mechanism of nanoclay in other general purpose elastomers also. ...

Ganesh C. Basak; K. Dinesh Kumar; Abhijit Bandyopadhyay; Anil K. Bhowmick

2010-10-12T23:59:59.000Z

150

Low band gap polymers Organic Photovoltaics  

E-Print Network [OSTI]

Low band gap polymers for Organic Photovoltaics Eva Bundgaard Ph.D. Dissertation Risø National Bundgaard Title: Low band gap polymers for Organic photovoltaics Department: The polymer department Report the area of organic photovoltaics are focusing on low band gap polymers, a type of polymer which absorbs

151

Polymer Crowding and Shape Distributions in Polymer-Nanoparticle Mixtures  

E-Print Network [OSTI]

Macromolecular crowding can influence polymer shapes, which is important for understanding the thermodynamic stability of polymer solutions and the structure and function of biopolymers (proteins, RNA, DNA) under confinement. We explore the influence of nanoparticle crowding on polymer shapes via Monte Carlo simulations and free-volume theory of a coarse-grained model of polymer-nanoparticle mixtures. Exploiting the geometry of random walks, we model polymer coils as effective penetrable ellipsoids, whose shapes fluctuate according to the probability distributions of the eigenvalues of the gyration tensor. Accounting for the entropic cost of a nanoparticle penetrating a larger polymer coil, we compute the crowding-induced shift in the shape distributions, radius of gyration, and asphericity of ideal polymers in a theta solvent. With increased nanoparticle crowding, we find that polymers become more compact (smaller, more spherical), in agreement with predictions of free-volume theory. Our approach can be easily extended to nonideal polymers in good solvents and used to model conformations of biopolymers in crowded environments.

Wei Kang Lim; Alan R. Denton

2014-10-24T23:59:59.000Z

152

Metal-Polymer Interactions in a Polymer/Metal Nanocomposite  

Science Journals Connector (OSTI)

A poly(t-butyl acrylate)/gold nanocomposite sandwich was annealed to induce diffusion of the gold particles, which was monitored using Rutherford backscattering spectrometry. Marker motion experiments were also performed to probe particle and polymer mobilities independently. The experiments revealed that particle mobility was decreased by 2 to 3 orders of magnitude compared with the predictions by Stokes-Einstein theory. Diffusion of polymer molecules through a gold particle layer is decreased by a much smaller extent. These results are attributed to bridging between particles arising from slow exchange kinetics of polymer segments at the polymer/metal interface.

Douglas H. Cole; Kenneth R. Shull; L. E. Rehn; P. Baldo

1997-06-30T23:59:59.000Z

153

Relaxation imaging to characterize lightweight polymer-crosslinked aerogels .  

E-Print Network [OSTI]

??"Silica aerogels are three-dimensional assemblies of silica nanoparticles with extremely low densities. In some instances, the internal void volume is more than 90% of the… (more)

Satterfield, EmmaLou Theresa, 1982-

2011-01-01T23:59:59.000Z

154

Energy Storage in Ferroelectric Polymer Nanocomposites Filled with Core–Shell Structured Polymer@BaTiO3 Nanoparticles: Understanding the Role of Polymer Shells in the Interfacial Regions  

Science Journals Connector (OSTI)

The interfacial region plays a critical role in determining the electrical properties and energy storage density of dielectric polymer nanocomposites. However, we still know a little about the effects of electrical properties of the interfacial regions on ...

Ming Zhu; Xingyi Huang; Ke Yang; Xing Zhai; Jun Zhang; Jinliang He; Pingkai Jiang

2014-11-03T23:59:59.000Z

155

Interstitial BiO molecule as a broadband IR luminescence centre in bismuth-doped silica glass  

SciTech Connect (OSTI)

Experimental data on absorption and luminescence in optical fibres with a Bi : SiO{sub 2} glass core are compared to experimentally determined and calculated spectroscopic properties of the BiO molecule. The results suggest that the IR luminescence of Bi : SiO{sub 2} glass is due to interstitial BiO molecules. This assumption is supported by quantum-chemical simulation results for a BiO molecule in a ring interstice of the silica glass network.

Sokolov, V O; Plotnichenko, V G; Dianov, Evgenii M [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation)

2011-12-31T23:59:59.000Z

156

Photochemical Crosslinking Reactions in Polymers.  

E-Print Network [OSTI]

??The post-synthesis modification of polymer properties has very broad applications in industry. It is employed to produce products that are impossible to directly synthesize, modify… (more)

Carbone, Nicholas

2012-01-01T23:59:59.000Z

157

Acoustic emission during polymer crystallization  

Science Journals Connector (OSTI)

... .G.; part support to L.K.) Acoustic Emission, Special Technical Publication 505, ASTM, Philadelphia, 1971; Grabec, I. & Peterlin, A. J. Polymer Sci. ...

A. Galeski; L. Koenczoel; E. Piorkowska; E. Baer

1987-01-01T23:59:59.000Z

158

Photopatterned conjugated polymer electrochromic nanofibers Arvind Kumara  

E-Print Network [OSTI]

Photopatterned conjugated polymer electrochromic nanofibers on paper Arvind Kumara , Chris Asemotaa. Electrochromic nanofibers of conducting polymer (terthiophene) have been deposited over a conventional paper in electrochromic characters. SEM images of the conducting polymer nanofibers together with the cellulose fibers

Otero, Toribio Fernández

159

Molecular oxygen sensors based on photoluminescent silica aerogels  

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

Molecular oxygen sensors based on photoluminescent silica aerogels Molecular oxygen sensors based on photoluminescent silica aerogels Title Molecular oxygen sensors based on photoluminescent silica aerogels Publication Type Journal Article Year of Publication 1998 Authors Ayers, Michael R., and Arlon J. Hunt Journal Journal of Non-Crystalline Solids Volume 225 Pagination 343-347 Keywords aerogel, air pressure, oxygen concentration, oxygen molecules, photoluminescence Abstract Photoluminescent silica aerogel acts as the active element of an optical sensor for molecular oxygen. The luminescent aerogel is prepared by the action of energized reducing gases on a standard silica aerogel. Intensity of aerogel photoluminescence decreases as the collision frequency between oxygen molecules and the luminescent carriers in the aerogel matrix increases. This behavior is a characteristic of many photoluminescent materials and arises from a transfer of energy from the aerogel to surrounding oxygen molecules. A sensor for oxygen concentration or air pressure can therefore be simply constructed utilizing an ultraviolet source for excitation and a suitable detector for the emitted visible signal. Stern-Volmer quenching constants for the aerogel sensing element are 1.55×10-2 Torr-1 for hydrophilic aerogel and 2.4×10-3 Torr-1 for hydrophobic aerogel.

160

Surface characterization of silica glass substrates treated by atomic hydrogen  

SciTech Connect (OSTI)

Silica glass substrates with very flat surfaces were exposed to atomic hydrogen at different temperatures and durations. An atomic force microscope was used to measure root-mean-square (RMS) roughness and two-dimensional power spectral density (PSD). In the treatment with atomic hydrogen up to 900 °C, there was no significant change in the surface. By the treatment at 1000 °C, the changes in the RMS roughness and the PSD curves were observed. It was suggested that these changes were caused by etching due to reactions of atomic hydrogen with surface silica. By analysis based on the k-correlation model, it was found that the spatial frequency of the asperities became higher with an increase of the treatment time. Furthermore, the data showed that atomic hydrogen can flatten silica glass surfaces by controlling heat-treatment conditions. - Highlights: • Silica glass surface was treated by atomic hydrogen at various temperatures. • Surface roughness was measured by an atomic force microscope. • Roughness data were analyzed by two-dimensional power spectral density. • Atomic hydrogen can flatten silica glass surfaces.

Inoue, Hiroyuki [Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo 153-8505 (Japan); Masuno, Atsunobu, E-mail: masuno@iis.u-tokyo.ac.jp [Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo 153-8505 (Japan); Ishibashi, Keiji [Canon ANELVA Corporation, Asao-ku, Kawasaki, Kanagawa 215-8550 (Japan); Tawarayama, Hiromasa [Kawazoe Frontier Technologies Corporation, Kuden 931-113, Sakae-ku, Yokohama, Kanagawa 247-0014 (Japan); Zhang, Yingjiu; Utsuno, Futoshi [Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo 153-8505 (Japan); Koya, Kazuo; Fujinoki, Akira [Shin Etsu Quartz Prod. Co., Ltd., Res and Applicat Lab, Fukushima 963-0725 (Japan); Kawazoe, Hiroshi [Kawazoe Frontier Technologies Corporation, Kuden 931-113, Sakae-ku, Yokohama, Kanagawa 247-0014 (Japan)

2013-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Stress-tuned conductor-polymer composite for use in sensors  

DOE Patents [OSTI]

A method for making a composite polymeric material with electrical conductivity determined by stress-tuning of the conductor-polymer composite, and sensors made with the stress-tuned conductor-polymer composite made by this method. Stress tuning is achieved by mixing a miscible liquid into the polymer precursor solution or by absorbing into the precursor solution a soluble compound from vapor in contact with the polymer precursor solution. The conductor may or may not be ordered by application of a magnetic field. The composite is formed by polymerization with the stress-tuning agent in the polymer matrix. The stress-tuning agent is removed following polymerization to produce a conductor-polymer composite with a stress field that depends on the amount of stress-tuning agent employed.

Martin, James E; Read, Douglas H

2013-10-22T23:59:59.000Z

162

Hybrid Silicon Nanocone–Polymer Solar Cells  

Science Journals Connector (OSTI)

Hybrid Silicon Nanocone–Polymer Solar Cells ... In this study, we demonstrate a hybrid solar cell composed of Si nanocones and conductive polymer. ...

Sangmoo Jeong; Erik C. Garnett; Shuang Wang; Zongfu Yu; Shanhui Fan; Mark L. Brongersma; Michael D. McGehee; Yi Cui

2012-04-30T23:59:59.000Z

163

Webinar: Hydrogen Production by Polymer Electrolyte Membrane...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Production by Polymer Electrolyte Membrane (PEM) Electrolysis-Spotlight on Giner and Proton Webinar: Hydrogen Production by Polymer Electrolyte Membrane (PEM) Electrolysis-Spotligh...

164

Polymers in a Vacuum  

SciTech Connect (OSTI)

In a variety of situations, isolated polymer molecules are found in a vacuum, and here we examine their properties. Angular momentum conservation is shown to significantly alter the average size of a chain and its conservation is only broken slowly by thermal radiation. For an ideal chain, the time autocorrelation for monomer position oscillates with a period proportional to chain length. The oscillations and damping are analyzed in detail. Short-range repulsive interactions suppress oscillations and speed up relaxation, but stretched chains still show damped oscillatory correlations.

Deutsch, J. M. [Department of Physics, University of California, Santa Cruz, California 95064 (United States)

2007-12-07T23:59:59.000Z

165

Silica membranes for hydrogen separation from coal gas. Final report  

SciTech Connect (OSTI)

This project is a continuation of a previous DOE-UCR project (DE-FG22- 89PC89765) dealing with the preparation of silica membranes highly permselective to hydrogen at elevated temperatures, suitable for hydrogen separation from coal gas. The membranes prepared in the previous project had very high selectivity but relatively low permeance. Therefore, the general objectives of this project were to improve the permeance of these membranes and to obtain fundamental information about membrane structure and properties. The specific objectives were: (1) to explore new silylation reagents and reaction conditions with the purpose of reducing the thickness and increasing the permeance of silica membranes prepared by chemical vapor deposition (CVD), (2) to characterize the membrane structure, (3) to delineate mechanism and kinetics of deposition, (4) to measure the permeability of silica layers at different extents of deposition, and (5) to mathematically model the relationship between structure and deposition kinetics.

Gavalas, G.R.

1996-01-01T23:59:59.000Z

166

Potassium geopolymer foams made with silica fume pore forming agent for thermal insulation  

Science Journals Connector (OSTI)

Porous potassium based geopolymers with a mutli-scale porosity were synthesized. Silica fume is introduced as an additive to the geopolymer formulation. The free silicon contained inside this silica fume is ox...

Joseph Henon; Arnaud Alzina; Joseph Absi…

2013-02-01T23:59:59.000Z

167

Vacuum flash evaporated polymer composites  

DOE Patents [OSTI]

A method for fabrication of polymer composite layers in a vacuum is disclosed. More specifically, the method of dissolving salts in a monomer solution, vacuum flash evaporating the solution, condensing the flash evaporated solution as a liquid film, and forming the condensed liquid film into a polymer composite layer on a substrate is disclosed.

Affinito, J.D.; Gross, M.E.

1997-10-28T23:59:59.000Z

168

Materials - Recycling - Polymer Matrix Composites  

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

Recycling of Polymer Matrix Composites Recycling of Polymer Matrix Composites Polymer matrix composites Carbon fibers recovered from a epoxy-based polymer matrix composite. Carbon fiber reinforced polymer matrix composites (PMCs) are materials with superior strength-to-weight ratios. Finding increased applications in the aerospace industry, PMCs are now being evaluated for possible use in automobile construction. The materialÂ’s high cost, however, along with concerns about whether the PMCs will be recyclable when the vehicles reach the end of their useful lives, are barriers to its widespread use. With funding provided by the U.S. Department of EnergyÂ’s Vehicle Technologies Program (formerly called the Office of Advanced Transportation Technologies), Argonne is developing an efficient and cost-effective

169

Accelerated Characterization of Polymer Properties  

SciTech Connect (OSTI)

This report describes the efforts to develop a suite of microanalysis techniques that can rapidly measure a variety of polymer properties of industrial importance, including thermal, photo-oxidative, and color stability; as well as ductility, viscosity, and mechanical and antistatic properties. Additional goals of the project were to direct the development of these techniques toward simultaneous measurements of multiple polymer samples of small size in real time using non-destructive and/or parallel or rapid sequential measurements, to develop microcompounding techniques for preparing polymers with additives, and to demonstrate that samples prepared in the microcompounder could be analyzed directly or used in rapid off-line measurements. These enabling technologies are the crucial precursors to the development of high-throughput screening (HTS) methodologies for the polymer additives industry whereby the rate of development of new additives and polymer formulations can be greatly accelerated.

R. Wroczynski; l. Brewer; D. Buckley; M. Burrell; R. Potyrailo

2003-07-30T23:59:59.000Z

170

Polymer formulations for gettering hydrogen  

DOE Patents [OSTI]

A novel method for preparing a hydrogenation composition comprising organic polymer molecules having carbon--carbon double bonds, for removing hydrogen from the atmosphere within enclosed spaces and particularly from atmospheres within enclosed spaces that contain air, water vapor, oxygen, carbon dioxide or ammonia. The organic polymers molecules containing carbon--carbon double bonds throughout their structures, preferably polybutadiene, polyisoprene and derivatives thereof, intimately mixed with an insoluble noble metal catalyst composition. High molecular weight polymers may be added to the organic polymer/catalyst mixture in order to improve their high temperature performance. The hydrogenation composition is prepared by dispersing the polymers in a suitable solvent, forming thereby a solution suspension, flash-freezing droplets of the solution in a liquid cryogen, freeze-drying the frozen droplets to remove frozen solvent incorporated in the droplets, and recovering the dried powder thus formed.

Shepodd, Timothy J. (330 Thrasher Ave., Livermore, CA 94550); Even, Jr., William R. (4254 Drake Way, Livermore, CA 94550)

2000-01-01T23:59:59.000Z

171

CX-011125: Categorical Exclusion Determination | Department of...  

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

CX-011125: Categorical Exclusion Determination A New Generation of Building Insulation by Foaming Polymer Blend Materials with Carbon Dioxide CX(s) Applied: A9, B3.6 Date:...

172

Contracting Polymer with Current  

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

Contracting Polymer with Current Contracting Polymer with Current Name: Ian Status: student Grade: 9-12 Location: PA Country: USA Date: Summer 2011 Question: Hello and thank you in advance. I have previously read of a material ( a kind of "rubber") that contracts when an electric current is applied. My question is what is this material, how does it work/what is it made of? Thank you very much. Replies: Hi Ian, I believe the material you are referring to is a kind of piezoelectric rubber. Piezoelectric materials (usually they are special types of ceramics or crystals) produce an electrical voltage when compressed of otherwise subjected to stress. They also do the opposite... they slightly expand or contract when a voltage is applied. But the amount they expand or contract is very small indeed. For example, one square meter of the recently discovered piezoelectric rubber materials typically contracts a mere 100 picometers for ever applied volt. Translated into everyday measurements, this means that if you apply a voltage of 1 Volt to a one foot long piece of this rubber, it will only contract less than half a billionth of an inch! Applying 100 volts will cause it to contract just under 50 billionths of an inch!

173

Hierarchical Silica Nanostructures Inspired by Diatom Algae Yield Superior Deformability, Toughness, and Strength  

E-Print Network [OSTI]

Hierarchical Silica Nanostructures Inspired by Diatom Algae Yield Superior Deformability, Toughness algae that is mainly composed of amorphous silica, which features a hierarchical structure that ranges in diatom algae as a basis to study a bioinspired nanoporous material implemented in crystalline silica. We

Buehler, Markus J.

174

Tailoring Elastic Properties of Silica Aerogels Cross-Linked with Polystyrene  

Science Journals Connector (OSTI)

The effect of incorporating an organic linking group, 1,6-bis(trimethoxysilyl)hexane (BTMSH), into the underlying silica structure of a styrene cross-linked silica aerogel is examined. ... Silica aerogels with their low density and thermal conductivity are potential candidates for various thermal, optical, and acoustic applications for aerospace including multipurpose structures for vehicles, space suits, and habitats (1). ...

Baochau N. Nguyen; Mary Ann B. Meador; Marissa E. Tousley; Brian Shonkwiler; Linda McCorkle; Daniel A. Scheiman; Anna Palczer

2009-02-19T23:59:59.000Z

175

Multicomponent Transport of Sulfate in a Goethite-Silica Sand System  

E-Print Network [OSTI]

Multicomponent Transport of Sulfate in a Goethite-Silica Sand System at Variable pH and Ionic of protons and sulfate on goethite and silica were used in combination with a one-dimensional mass-transport model to predict the transport of sulfate at variable pH and ionic strength in a goethite-silica system

Sparks, Donald L.

176

SULFUR POLYMER ENCAPSULATION.  

SciTech Connect (OSTI)

Sulfur polymer cement (SPC) is a thermoplastic polymer consisting of 95 wt% elemental sulfur and 5 wt% organic modifiers to enhance long-term durability. SPC was originally developed by the U.S. Bureau of Mines as an alternative to hydraulic cement for construction applications. Previous attempts to use elemental sulfur as a construction material in the chemical industry failed due to premature degradation. These failures were caused by the internal stresses that result from changes in crystalline structure upon cooling of the material. By reacting elemental sulfur with organic polymers, the Bureau of Mines developed a product that successfully suppresses the solid phase transition and significantly improves the stability of the product. SPC, originally named modified sulfur cement, is produced from readily available, inexpensive waste sulfur derived from desulfurization of both flue gases and petroleum. The commercial production of SPC is licensed in the United States by Martin Resources (Odessa, Texas) and is marketed under the trade name Chement 2000. It is sold in granular form and is relatively inexpensive ({approx}$0.10 to 0.12/lb). Application of SPC for the treatment of radioactive, hazardous, and mixed wastes was initially developed and patented by Brookhaven National Laboratory (BNL) in the mid-1980s (Kalb and Colombo, 1985; Colombo et al., 1997). The process was subsequently investigated by the Commission of the European Communities (Van Dalen and Rijpkema, 1989), Idaho National Engineering Laboratory (Darnell, 1991), and Oak Ridge National Laboratory (Mattus and Mattus, 1994). SPC has been used primarily in microencapsulation applications but can also be used for macroencapsulation of waste. SPC microencapsulation has been demonstrated to be an effective treatment for a wide variety of wastes, including incinerator hearth and fly ash; aqueous concentrates such as sulfates, borates, and chlorides; blowdown solutions; soils; and sludges. It is not recommended for treatment of wastes containing high concentrations of nitrates because of potentially dangerous reactions between sulfur, nitrate, and trace quantities of organics. Recently, the process has been adapted for the treatment of liquid elemental mercury and mercury contaminated soil and debris.

KALB, P.

2001-08-22T23:59:59.000Z

177

Polymer/clay aerogel composites with flame retardant agents: Mechanical, thermal and fire behavior  

Science Journals Connector (OSTI)

Abstract Aerogel is a class of material characterized by its high void content and extreme lightness. Different polymer/clay aerogels have been prepared by a simply freeze–thaw process from a suspension with poly(vinyl alcohol) (PVOH) and clay (Na+-MMT). Low density polymer/clay aerogels modified with flame retardant agents were prepared using a similar approach. The addition of flame retardant agents slightly increased the apparent density of the final composites whereas the compression properties were reduced due to the decrease in the polymer/clay interfacial bonding. An exception was the sample containing Al(OH)3 that exhibited higher modulus and stress at maximum deformation. Regarding thermal properties, the presence of ammonium polyphosphate (APP) or silica gel (SG) significantly slowed the rate of aerogel decomposition at the temperature range from 250 °C to 500 °C while the onset of polymer decomposition was not affected. Fire behavior was analyzed through cone calorimeter suggesting that either the presence of Al(OH)3 or APP reduced the heat release rate of PVOH/clay systems.

Liang Wang; Miguel Sánchez-Soto; Maria Lluisa Maspoch

2013-01-01T23:59:59.000Z

178

Monolithic Silica Stationary Phases in Liquid Chromatography  

Science Journals Connector (OSTI)

......second peak), trypsin inhibitor (third peak) (60). A...modified subsequently by chitosan and 2,6-sialyllactose...Different ratio of phosphate 97 inhibitors rofecoxib buffer & acetonitrile...determination of cyclooxygenase II inhibitors in human plasma. J. Chromatogr......

Imran Ali; Vinay D. Gaitonde; Hassan Y. Aboul-Enein

2009-07-01T23:59:59.000Z

179

Carbon nanotube-polymer composite actuators  

DOE Patents [OSTI]

The present invention discloses a carbon nanotube (SWNT)-polymer composite actuator and method to make such actuator. A series of uniform composites was prepared by dispersing purified single wall nanotubes with varying weight percents into a polymer matrix, followed by solution casting. The resulting nanotube-polymer composite was then successfully used to form a nanotube polymer actuator.

Gennett, Thomas (Denver, CO); Raffaelle, Ryne P. (Honeoye Falls, NY); Landi, Brian J. (Rochester, NY); Heben, Michael J. (Denver, CO)

2008-04-22T23:59:59.000Z

180

The workshop on conductive polymers: Final report  

SciTech Connect (OSTI)

Reports are made by groups on: polyacetylene, polyphenylene, polyaniline, and related systems; molecular, crystallographic, and defect structures in conducting polymers; heterocyclic polymers; synthesis of new and improved conducting polymers; future applications possibilities for conducting polymers; and challenges for improved understanding of properties. (DLC)

Not Available

1985-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Mechanized Silica Nanoparticles: A New Frontier in Theranostic Nanomedicine  

Science Journals Connector (OSTI)

Mechanized Silica Nanoparticles: A New Frontier in Theranostic Nanomedicine ... This article is part of the Theranostic Nanomedicine special issue. ... With the growth of nanomedicine, one can envisage the possibility of fabricating a theranostic vector that could release powerful therapeutics and diagnostic markers simultaneously and selectively to diseased tissue. ...

Michael W. Ambrogio; Courtney R. Thomas; Yan-Li Zhao; Jeffrey I. Zink; J. Fraser Stoddart

2011-06-15T23:59:59.000Z

182

Atmospheric Plasma Deposited Dense Silica Coatings on Plastics  

Science Journals Connector (OSTI)

Atmospheric Plasma Deposited Dense Silica Coatings on Plastics ... (8) Finally, some plasma techniques including atmospheric plasmas work at low gas temperature, are suitable for treating plastics with low glass transition temperatures, and can even be used on biological samples. ... These results suggest that the mechanism in the atm.-pressure plasma is the same as that in low-pressure plasmas. ...

Linying Cui; Alpana N. Ranade; Marvi A. Matos; Liam S. Pingree; Theo J. Frot; Geraud Dubois; Reinhold H. Dauskardt

2012-11-26T23:59:59.000Z

183

Silica-Supported Tantalum Clusters: Catalyst for Alkane Conversion  

SciTech Connect (OSTI)

Silica-supported tantalum clusters (on average, approximately tritantalum) were formed by the treatment, in either H{sub 2} or ethane, of adsorbed Ta(CH{sub 2}Ph){sub 5}; the supported catalyst is active for ethane conversion to methane and propane at 523 K, with the used catalyst containing clusters of the same average nuclearity as the precursor.

Nemana ,S.; Gates, B.

2006-01-01T23:59:59.000Z

184

Fabrication of magnetite/silica/titania core-shell nanoparticles  

Science Journals Connector (OSTI)

Fe3O4/SiO2/TiO2 core-shell nanoparticles were synthesized via a sol-gel method with the aid of sonication. Fe3O4 nanoparticles were being encapsulated within discrete silica nanospheres, ...

Suh Cem Pang; Sze Yun Kho; Suk Fun Chin

2012-01-01T23:59:59.000Z

185

Formation of Hollow Gallium Nitride Spheres via Silica Sphere Templates  

Science Journals Connector (OSTI)

Formation of Hollow Gallium Nitride Spheres via Silica Sphere Templates ... To form reasonably uniform gallium oxide shells, the amounts of urea and water added to the reaction mixture were varied. ... Due to the low solubility of urea in 2-propanol, addition of a larger amount of urea than that used in this study is not desirable. ...

Chun-Neng Lin; Michael H. Huang

2008-12-30T23:59:59.000Z

186

Moisture Transport in Silica Gel Packed Beds: II. Experimental Study  

SciTech Connect (OSTI)

Experiments have been performed to obtain the transient response of a thin adiabatic packed bed of silica gel after a step change in inlet air conditions, comparisons are made with predictions using a solid-side resistance model and a pseudo-gas-side controlled model and better agreement obtained with the former model.

Pesaran, A. A.; Mills, A. F.

1986-08-01T23:59:59.000Z

187

Surface Aggregate Structure of Nonionic Surfactants on Silica Nanoparticles  

E-Print Network [OSTI]

against flat solid surfaces has been gained mainly by neutron reflectometry (NR)1,2,4 and atomic force light scattering and small-angle neutron scattering (SANS) using a H2O/D2O mixture matching the silica

Paris-Sud XI, Université de

188

Drag reducing polymers as simple indicators of hemolytic potential in biomechanical devices  

E-Print Network [OSTI]

An experimental study was carried out to determine if drag reducing polymers can be simple indicators of hemolytic potential in biomechanical devices. Specifically, three different blood pumps, known as a left ventricle ...

Shieh, Sarah

2009-01-01T23:59:59.000Z

189

Thermodynamics of tubelike flexible polymers  

E-Print Network [OSTI]

In this work we present the general phase behavior of short tubelike flexible polymers. The geometric thickness constraint is implemented through the concept of the global radius of curvature. We use sophisticated Monte Carlo sampling methods to simulate small bead-stick polymer models with Lennard-Jones interaction among non-bonded monomers. We analyze energetic fluctuations and structural quantities to classify conformational pseudophases. We find that the tube thickness influences the thermodynamic behavior of simple tubelike polymers significantly, i.e., for given temperature, the formation of secondary structures strongly depends on the tube thickness.

Thomas Vogel; Thomas Neuhaus; Michael Bachmann; Wolfhard Janke

2009-07-17T23:59:59.000Z

190

Thermodynamics of tubelike flexible polymers  

Science Journals Connector (OSTI)

In this work, we discuss the general phase behavior of short tubelike flexible polymers. The geometric thickness constraint is implemented through the concept of the global radius of curvature. We use sophisticated Monte Carlo sampling methods to simulate small bead-stick polymer models with Lennard-Jones interaction among nonbonded monomers. We analyze energetic fluctuations and structural quantities to classify conformational pseudophases. We find that the tube thickness influences the thermodynamic behavior of simple tubelike polymers significantly, i.e., for a given temperature, the formation of secondary structures strongly depends on the tube thickness.

Thomas Vogel; Thomas Neuhaus; Michael Bachmann; Wolfhard Janke

2009-07-16T23:59:59.000Z

191

Power scaling analysis of fiber lasers and amplifiers based on non-silica materials  

SciTech Connect (OSTI)

A developed formalism for analyzing the power scaling of diffraction limited fiber lasers and amplifiers is applied to a wider range of materials. Limits considered include thermal rupture, thermal lensing, melting of the core, stimulated Raman scattering, stimulated Brillouin scattering, optical damage, bend induced limits on core diameter and limits to coupling of pump diode light into the fiber. For conventional fiber lasers based upon silica, the single aperture, diffraction limited power limit was found to be 36.6kW. This is a hard upper limit that results from an interaction of the stimulated Raman scattering with thermal lensing. This result is dependent only upon physical constants of the material and is independent of the core diameter or fiber length. Other materials will have different results both in terms of ultimate power out and which of the many limits is the determining factor in the results. Materials considered include silica doped with Tm and Er, YAG and YAG based ceramics and Yb doped phosphate glass. Pros and cons of the various materials and their current state of development will be assessed. In particular the impact of excess background loss on laser efficiency is discussed.

Dawson, J W; Messerly, M J; Heebner, J E; Pax, P H; Sridharan, A K; Bullington, A L; Beach, R J; Siders, C W; Barty, C P; Dubinskii, M

2010-03-30T23:59:59.000Z

192

INSTRUMENTS-METHODS-36 Absorption and scattering lengths of high density silica aerogels with n = 1.07  

E-Print Network [OSTI]

angles could be the use of silica aerogels as radiator. Simultaneously, an aerogel ?erenkov counter is

L. Debenjak; P. Achenbach; J. Pochodzalla; T. Saito

193

A conjugated polymer plastic gel  

E-Print Network [OSTI]

We present a gel route to process highly oriented conjugated polymer films and fibers. The incorporation of hexafluoroisopropanol, a strong and stable dipolar group, to the polythiophene backbone enhances the solubility ...

Alcazar Jorba, Daniel

2008-01-01T23:59:59.000Z

194

Polymers For Advanced Lithium Batteries  

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

Accomplishments 1 m SEM of cathode LiFePO 4 +Binder (5050) Nothing else, no optimization Li metal (anode) Al current collector Polymer electrolyte membrane (S-EO-S)...

195

Polymers, Fractals, and Ceramic Materials  

Science Journals Connector (OSTI)

...application primarily as optical coatings and aerogels. Aerogels (1...4) Gelation //Polymer x Coating_rn Film Monomer Aggregation...Sintering.......... Aerogel Monolith Fig. 1. Ceramic...desired for index-matched coatings, then base-catalyzed materials...

DALE W. SCHAEFER

1989-02-24T23:59:59.000Z

196

Layered plasma polymer composite membranes  

DOE Patents [OSTI]

Layered plasma polymer composite fluid separation membranes are disclosed, which comprise alternating selective and permeable layers for a total of at least 2n layers, where n is [>=]2 and is the number of selective layers. 2 figs.

Babcock, W.C.

1994-10-11T23:59:59.000Z

197

Characterization of macro-length conducting polymers and the development of a conducting polymer rotary motor  

E-Print Network [OSTI]

Conducting polymers are a subset of materials within the electroactive polymer class that exhibit active mechanical deformations. These deformations induce stresses and strains that allow for conducting polymers to be used ...

Schmid, Bryan D. (Bryan David), 1981-

2005-01-01T23:59:59.000Z

198

High cation transport polymer electrolyte  

DOE Patents [OSTI]

A solid state ion conducting electrolyte and a battery incorporating same. The electrolyte includes a polymer matrix with an alkali metal salt dissolved therein, the salt having an anion with a long or branched chain having not less than 5 carbon or silicon atoms therein. The polymer is preferably a polyether and the salt anion is preferably an alkyl or silyl moiety of from 5 to about 150 carbon/silicon atoms.

Gerald, II, Rex E. (Brookfield, IL); Rathke, Jerome W. (Homer Glen, IL); Klingler, Robert J. (Westmont, IL)

2007-06-05T23:59:59.000Z

199

High Temperature Polymer Membrane Development at Argonne National...  

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

Polymer Membrane Development at Argonne National Laboratory High Temperature Polymer Membrane Development at Argonne National Laboratory Summary of ANL's high temperature polymer...

200

Hydrogen-Bond Acidic Polymers for Chemical Vapor Sensing. | EMSL  

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

Acidic Polymers for Chemical Vapor Sensing. Hydrogen-Bond Acidic Polymers for Chemical Vapor Sensing. Abstract: A review with 171 references. Hydrogen-bond acidic polymers for...

Note: This page contains sample records for the topic "determination silica polymer" 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

SUPER HARD SURFACED POLYMERS  

SciTech Connect (OSTI)

High energy ion beam surface treatments were applied to a selected group of polymers. Of the six materials in the present study, four were thermoplastics (polycarbonate, polyethylene, polyethylene terephthalate, and polystyrene) and two were thermosets (epoxy and polyimide). The particular epoxy evaluated in this work is one of the resins used in formulating fiber reinforced composites for military helicopter blades. Measures of mechanical properties of the near surface regions were obtained by nanoindentation hardness and pin on disk wear. Attempts were also made to measure erosion resistance by particle impact. All materials were hardness tested. Pristine materials were very soft, having values in the range of approximately 0.1 to 0.5 GPa. Ion beam treatment increased hardness by up to 50 times compared to untreated materials. For reference, all materials were hardened to values higher than those typical of stainless steels. Wear tests were carried out on three of the materials, PET, PI and epoxy. On the ion beam treated epoxy no wear could be detected, whereas the untreated material showed significant wear.

Mansur, Louis K [ORNL] [ORNL; Bhattacharya, R [UES, Incorporated, Dayton, OH] [UES, Incorporated, Dayton, OH; Blau, Peter Julian [ORNL] [ORNL; Clemons, Art [ORNL] [ORNL; Eberle, Cliff [ORNL] [ORNL; Evans, H B [UES, Incorporated, Dayton, OH] [UES, Incorporated, Dayton, OH; Janke, Christopher James [ORNL] [ORNL; Jolly, Brian C [ORNL] [ORNL; Lee, E H [Consultant, Milpitas, CA] [Consultant, Milpitas, CA; Leonard, Keith J [ORNL] [ORNL; Trejo, Rosa M [ORNL] [ORNL; Rivard, John D [ORNL] [ORNL

2010-01-01T23:59:59.000Z

202

1 LOST PRODUCTION AS CONSEQUENSE OF SILICA SCALING IN CERRO  

E-Print Network [OSTI]

Mineral scale depositation occurs in many of the Cerro Prieto wells, but the main problems occurs by silica (SiO2) scale both pipes and reservoir zones close to the downhole. In Cerro Prieto geothermal field three types of scales are found; calcium carbonate (calcite), amorphous silica (SiO2), and metallic sulfides (mainly iron, and lesser lead and cooper). The scale causes lost production and it is necessary to make around 12 workover each year to recover the steam lost. When scaling problems occurred inside casing production is more easier to recover the production that scaling occurred in the reservoir zones, because it caused a skin damage (permeability decrease) in the reservoir zones close to the bottomhole. This paper analyze and discus the scaling problems and discuss the task developed to avoid and minimized the decline wells production, as to recover the production using workover alternatives.

Prieto Geothermal; Wells Mexico; Juan De; Dios Ocampo; Díaz Sara; Lilia Moya; Jesús De; León Vivar

203

Silica aerogels modified by functional and nonfunctional organic groups  

SciTech Connect (OSTI)

Organically substituted silica aerogels were prepared from RSi(OR`){sub 3}/Si(OR`){sub 4} mixtures, followed by supercritical drying. The typical microstructure and the resulting physical properties of silica aerogels are retained, if the portion of R-Si units is below 10-20%. However, new properties are supplemented, such as hydrophobicity (which makes the aerogels insensitive towards moisture), a higher compliance, and the possibility to incorporate functional organic groups. Controlled pyrolysis of the organically substituted aerogels allows to coat the inner surface of the aerogels with nanometer-sized carbon structures. This results in a very efficient infrared opacification and improved heat insulation properties at high temperatures. 5 refs., 2 figs.

Schubert, U.; Huesing, N.; Schwertfeger, F. [Universitaet Wien (Austria)

1996-12-31T23:59:59.000Z

204

Nimesulide adsorbed on silica aerogel using supercritical carbon dioxide  

Science Journals Connector (OSTI)

Silica aerogel (SA) was loaded with nimesulide, a drug model compound, to demonstrate the potentiality of adsorption processes based on the usage of supercritical carbon dioxide to treat poorly water-soluble drugs, forming new kinds of drug delivery systems. Adsorption isotherms and kinetics were measured and described by models. The effect of pressure, temperature and solution concentration on loaded SA were also studied. Modelling of kinetic data showed that the sorption process was best described by a pseudo-second-order model. The adsorption isotherm data were best fitted by the Freundlich isotherm. The drug/SA composites were characterized using scanning electron microscopy, X-ray microanalysis, and FT-IR. Release kinetics of the adsorbed drug were also evaluated by in vitro dissolution tests. Results showed that nimesulide can be uniformly dispersed into the aerogel and that the release rate of nimesulide from the composite, constituted by drug and silica aerogel, is much faster than that of the crystalline drug.

Giuseppe Caputo; Mariarosa Scognamiglio; Iolanda De Marco

2012-01-01T23:59:59.000Z

205

Surface Complexation Model for Strontium Sorption to Amorphous Silica and Goethite  

SciTech Connect (OSTI)

Strontium sorption to amorphous silica and goethite was measured as a function of pH and dissolved strontium and carbonate concentrations at 25 C. Strontium sorption gradually increases from 0 to 100% from pH 6 to 10 for both phases and requires multiple outer-sphere surface complexes to fit the data. All data are modeled using the triple layer model and the site-occupancy standard state; unless stated otherwise all strontium complexes are mononuclear. Strontium sorption to amorphous silica in the presence and absence of dissolved carbonate can be fit with tetradentate Sr{sup 2+} and SrOH{sup +} complexes on the {beta}-plane and a monodentate Sr{sup 2+} complex on the diffuse plane to account for strontium sorption at low ionic strength. Strontium sorption to goethite in the absence of dissolved carbonate can be fit with monodentate and tetradentate SrOH{sup +} complexes and a tetradentate binuclear Sr{sup 2+} species on the {beta}-plane. The binuclear complex is needed to account for enhanced sorption at high strontium surface loadings. In the presence of dissolved carbonate additional monodentate Sr{sup 2+} and SrOH{sup +} carbonate surface complexes on the {beta}-plane are needed to fit strontium sorption to goethite. Modeling strontium sorption as outer-sphere complexes is consistent with quantitative analysis of extended X-ray absorption fine structure (EXAFS) on selected sorption samples that show a single first shell of oxygen atoms around strontium indicating hydrated surface complexes at the amorphous silica and goethite surfaces. Strontium surface complexation equilibrium constants determined in this study combined with other alkaline earth surface complexation constants are used to recalibrate a predictive model based on Born solvation and crystal-chemistry theory. The model is accurate to about 0.7 log K units. More studies are needed to determine the dependence of alkaline earth sorption on ionic strength and dissolved carbonate and sulfate concentrations for the development of a robust surface complexation database to estimate alkaline earth sorption in the environment.

Carroll, S; Robers, S; Criscenti, L; O'Day, P

2007-11-30T23:59:59.000Z

206

A molecular dynamics investigation of the unusual concentration dependencies of Fick diffusivities in silica mesopores  

SciTech Connect (OSTI)

Molecular Dynamics (MD) simulations were carried out to determine the self-diffusivitiy, D{sub i,self}, the Maxwell–Stefan diffusivity, Ð{sub i}, and the Fick diffusivity, D{sub i}, for methane (C1), ethane (C2), propane (C3), n-butane (nC4), n-pentane (nC5), n-hexane (nC6), n-heptane (nC7), and cyclohexane (cC6) in cylindrical silica mesopores for a range of pore concentrations. The MD simulations show that zero-loading diffusivity Ð{sub i}(0) is consistently lower, by up to a factor of 20, than the values anticipated by the classical Knudsen formula. The concentration dependence of the Fick diffusivity, D{sub i} is found to be unusually complex, and displays a strong minimum in some cases; this characteristic can be traced to molecular clustering.

Krishna, Rajamani; van Baten, Jasper M

2011-01-01T23:59:59.000Z

207

Silica microparticles precipitation by two processes using supercritical fluids  

Science Journals Connector (OSTI)

Silica microspheres are of great interest for several applications in areas such as medicine, biochemistry, colloidal chemistry and aerosol research. In this work, the sol–gel method was used to obtain such microparticles in two different ways. One of the methods applied was supercritical reaction; a high temperature process using ethanol as a supercritical fluid (SCF reaction). Another approach to obtaining silica microparticles was Supercritical AntiSolvent (SAS) process, as a low temperature process, using supercritical carbon dioxide (scCO2). A tetraethyl orthosilicate (TEOS) and water solution (1:4 molar ratio) was dissolved in ethanol and then pumped into an autoclave at 100 bar and 523 K for the SCF reaction process, and at 120 bar and 313 K in the case of the SAS process. All the experiments led to a successful precipitation of silica microparticles, in the micrometer range. In all cases spherical morphology and no agglomeration was found. Furthermore, the main textural characteristics of such powders were obtained by nitrogen physisorption experiments. Results reveal spherical microparticles with nanopores smaller than 1 nm in size when using supercritical ethanol, and bulky microparticles with smooth surfaces when using scCO2.

A. Montes; M.D. Gordillo; C. Pereyra; N. de la Rosa-Fox; E.J. Martínez de la Ossa

2013-01-01T23:59:59.000Z

208

Lime–Alumina–Silica processing incorporating minerals  

Science Journals Connector (OSTI)

The use of naturally occurring minerals to enhance the physical and mechanical properties of industrial ceramics such as alumina is an attractive alternative to synthetic materials due to cost, chemical stability and availability. Two systems, have been chosen for investigation, alumina–kyanite to produce an alumina–mullite composite and alumina–wollastonite to produce a lime aluminosilicate. Wet processing conditions were optimised using pH/rheology and microelectrophoresis techniques followed by slip casting. The resulting green compacts were subjected to a variety of sintering regimes to produce the desired composites. Sintered products were characterised by techniques such as electron probe microanalysis, hardness tests and toughness determinations. Results are discussed, both in terms of enhanced properties realised (toughness, wear resistance, dielectric), and with respect to the viability of using natural minerals in this application.

R.H Bryden; D.G Goski; W.F Caley

1999-01-01T23:59:59.000Z

209

Sum-frequency spectroscopic studies: I. Surface melting of ice, II. Surface alignment of polymers  

SciTech Connect (OSTI)

Surface vibrational spectroscopy via infrared-visible sum-frequency generation (SFG) has been established as a useful tool to study the structures of different kinds of surfaces and interfaces. This technique was used to study the (0001) face of hexagonal ice (Ih). SFG spectra in the O-H stretch frequency range were obtained at various sample temperatures. For the vapor(air)/ice interface, the degree of orientational order of the dangling OH bonds at the surface was measured as a function of temperature. Disordering sets in around 200 K and increases dramatically with temperature, which is strong evidence of surface melting of ice. For the other ice interfaces (silica/OTS/ice and silica/ice), a similar temperature dependence of the hydrogen bonded OH stretch peak was observed; the free OH stretch mode, however, appears to be different from that of the vapor (air)/ice interface due to interactions at the interfaces. The technique was also used to measure the orientational distributions of the polymer chains on a rubbed polyvinyl alcohol surface. Results show that the polymer chains at the surface appear to be well aligned by rubbing, and the adsorbed liquid crystal molecules are aligned, in turn, by the surface polymer chains. A strong correlation exists between the orientational distributions of the polymer chains and the liquid crystal molecules, indicating that the surface-induced bulk alignment of a liquid crystal film by rubbed polymer surfaces is via an orientational epitaxy-like mechanism. This thesis also contains studies on some related issues that are crucial to the above applications. An experiment was designed to measure SFG spectra in both reflection and transmission. The result confirms that SFG in reflection is generally dominated by the surface contribution. Another issue is the motional effect due to fast orientational motion of molecules at a surface or interface. Calculations show that the effect is significant if the molecular orientation varies over a broad range within the vibrational relaxation time. The stretch vibration of the free OH bonds at the vapor/water interface is used to illustrate the importance of the effect.

Wei, Xing

2000-12-21T23:59:59.000Z

210

Process for hardening the surface of polymers  

DOE Patents [OSTI]

Hard surfaced polymers and the method for making them is generally described. Polymers are subjected to simultaneous multiple ion beam bombardment, that results in a hardening of the surface and improved wear resistance. 1 figure.

Mansur, L.K.; Lee, E.H.

1992-07-14T23:59:59.000Z

211

Mechanics of Polymer?Clay Nanocomposites  

Science Journals Connector (OSTI)

The mechanics of nanocomposites is critical in the design of nanomaterials with desirable properties. In this paper, the mechanics of polymer?clay nanocomposites is studied using a designed polymer and solution nanocomposite synthesis. A copolymer latex, ...

YuanQiao Rao; John M. Pochan

2006-12-16T23:59:59.000Z

212

Process to produce lithium-polymer batteries  

DOE Patents [OSTI]

A polymer bonded sheet product is described suitable for use as an electrode in a non-aqueous battery system. A porous electrode sheet is impregnated with a solid polymer electrolyte, so as to diffuse into the pores of the electrode. The composite is allowed to cool, and the electrolyte is entrapped in the porous electrode. The sheet products composed have the solid polymer electrolyte composition diffused into the active electrode material by melt-application of the solid polymer electrolyte composition into the porous electrode material sheet. The solid polymer electrolyte is maintained at a temperature that allows for rapid diffusion into the pores of the electrode. The composite electrolyte-electrode sheets are formed on current collectors and can be coated with solid polymer electrolyte prior to battery assembly. The interface between the solid polymer electrolyte composite electrodes and the solid polymer electrolyte coating has low resistance. 1 fig.

MacFadden, K.O.

1998-06-30T23:59:59.000Z

213

Transports of Polymer Nanomedicine in the Environment  

E-Print Network [OSTI]

With increasing production and commercial use of polymer nanomedicine and a lack of regulation to govern their disposal, polymer nanomedicine may enter into soils and ultimately into ground water system. In this dissertation, adsorption of polymeric...

Zhang, Ming

2013-11-14T23:59:59.000Z

214

Unwinding relaxation dynamics of polymers  

E-Print Network [OSTI]

The relaxation dynamics of a polymer wound around a fixed obstacle constitutes a fundamental instance of polymer with twist and torque and it is of relevance also for DNA denaturation dynamics. We investigate it by simulations and Langevin equation analysis. The latter predicts a relaxation time scaling as a power of the polymer length times a logarithmic correction related to the equilibrium fluctuations of the winding angle. The numerical data support this result and show that at short times the winding angle decreases as a power-law. This is also in agreement with the Langevin equation provided a winding-dependent friction is used, suggesting that such reduced description of the system captures the basic features of the problem.

Jean-Charles Walter; Marco Baiesi; Gerard Barkema; Enrico Carlon

2013-01-13T23:59:59.000Z

215

Nanoparticle Diffusion in Polymer Nanocomposites  

Science Journals Connector (OSTI)

Large-scale molecular dynamics simulations show that nanoparticle (NP) diffusivity in weakly interacting mixtures of NPs and polymer melts has two very different classes of behavior depending on their size. NP relaxation times and their diffusivities are completely described by the local, Rouse dynamics of the polymer chains for NPs smaller than the polymer entanglement mesh size. The motion of larger NPs, which are comparable to the entanglement mesh size, is significantly slowed by chain entanglements, and is not describable by the Stokes-Einstein relationship. Our results are in essentially quantitative agreement with a force-level generalized Langevin equation theory for all the NP sizes and chain lengths explored, and imply that for these lightly entangled systems, activated NP hopping is not important.

Jagannathan T. Kalathi; Umi Yamamoto; Kenneth S. Schweizer; Gary S. Grest; Sanat K. Kumar

2014-03-12T23:59:59.000Z

216

Solid-polymer-electrolyte fuel cells  

SciTech Connect (OSTI)

A transport model for polymer electrolytes is presented, based on concentrated solution theory and irreversible thermodynamics. Thermodynamic driving forces are developed, transport properties are identified and experiments devised. Transport number of water in Nafion 117 membrane is determined using a concentration cell. It is 1.4 for a membrane equilibrated with saturated water vapor at 25{degrees}C, decreases slowly as the membrane is dehydrated, and falls sharply toward zero as the water content approaches zero. The relation between transference number, transport number, and electroosmotic drag coefficient is presented, and their relevance to water-management is discussed. A mathematical model of transport in a solid-polymer-electrolyte fuel cell is presented. A two-dimensional membrane-electrode assembly is considered. Water management, thermal management, and utilization of fuel are examined in detail. The membrane separators of these fuel cells require sorbed water to maintain conductivity; therefore it is necessary to manage the water content in membranes to ensure efficient operation. Water and thermal management are interrelated. Rate of heat removal is shown to be a critical parameter in the operation of these fuel cells. Current-voltage curves are presented for operation on air and reformed methanol. Equations for convective diffusion to a rotating disk are solved numerically for a consolute point between the bulk concentration and the surface. A singular-perturbation expansion is presented for the condition where the bulk concentration is nearly equal to the consolute-point composition. Results are compared to Levich's solution and analysis.

Fuller, T.F.

1992-07-01T23:59:59.000Z

217

“Coffee-ring” patterns of polymer droplets  

Science Journals Connector (OSTI)

Dried droplets of polymer solutions carries the self-assembly behavior of polymer molecules by forming various patterns. Pattern formation is a consequence of deposition of molecules depending on motion of the contact line during the drying process. The contact line motion depends on initial polymer concentrations and hence entanglement. Thus depending on entanglement the patterns represent the ‘particle’ like or ‘collective’ behavior of polymer molecules.

Nupur Biswas; Alokmay Datta

2013-01-01T23:59:59.000Z

218

Post polymerization cure shape memory polymers  

DOE Patents [OSTI]

This invention relates to chemical polymer compositions, methods of synthesis, and fabrication methods for devices regarding polymers capable of displaying shape memory behavior (SMPs) and which can first be polymerized to a linear or branched polymeric structure, having thermoplastic properties, subsequently processed into a device through processes typical of polymer melts, solutions, and dispersions and then crossed linked to a shape memory thermoset polymer retaining the processed shape.

Wilson, Thomas S; Hearon, Michael Keith; Bearinger, Jane P

2014-11-11T23:59:59.000Z

219

Miscibility–dispersion, Interfacial Strength and Nanoclay Mobility Relationships in Polymer Nanocomposites  

SciTech Connect (OSTI)

Fully dispersed layered silicate nanoparticles (nanoclay) in a polymer matrix have provided a new class of multi-functional materials exhibiting several performance improvements over conventional composites. Yet the challenges of miscibility and interfacial strength might prevent nanocomposites from realizing their full potential. In this paper we demonstrate the effect of the chemical characteristics of the nanoclay on the miscibility and dispersion in the polymer matrix as well as on the interfacial strength of the bound polymer and the nanoclay mobility, all of which determine the macroscopic properties of the nanocomposite.

Carretero-González, J.; Retsos , H; Giannelis , E; Ezquerra , T; Hernández , M; López-Manchado, M

2009-01-01T23:59:59.000Z

220

Aerosol synthesis of macroporous silica adsorbents with high performance in paclitaxel purification from plant cell cultures  

Science Journals Connector (OSTI)

Abstract Macroporous spherical silica particles having high performance for the purification of paclitaxel were synthesized by spray pyrolysis using polystyrene nanoparticles as a template. In terms of increasing the purity and yield of paclitaxel, the synthesized macroporous silica showed the better performance than mesoporous silica of high surface area as well as commercial sylopute. The generation of macroporous with the sacrifice of losing surface area was proved to be helpful for enhancing the performance of adsorbents for paclitaxel purification. As a result, the high purity (67.3%) and yield (80.0%) of paclitaxel was achieved by using macroporous silica prepared by spray pyrolysis.

Hye Ran Jang; Jin-Hyun Kim; Kyeong Youl Jung

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Extensional rheology of shear-thickening fumed silica nanoparticles dispersed in an aqueous polyethylene  

E-Print Network [OSTI]

polyethylene oxide solution Sunilkumar Khandavalli and Jonathan P. Rothsteina) Mechanical and Industrial rheology of fumed silica nanoparticles dispersed in an aqueous polyethylene oxide (PEO) solution

Rothstein, Jonathan

222

E-Print Network 3.0 - ash slag silica Sample Search Results  

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

Engineering ; Materials Science 91 By-Products Utilization Summary: pozzolans include coal fly ash, blast furnace slag, silica fume, and other combustion ashes. When...

223

Silica banding in the deep-sea lithistid sponge Corallistes undulatus ...  

Science Journals Connector (OSTI)

The ?14C results for organic carbon trapped in the silica desmas, deposited after the 1960s, supports this assertion; only a small atmospheric nuclear weapons ...

224

Lab Trials of an Electricity Transmission Line Voltage Sensor Based on Thermally Poled Silica Fibre  

Science Journals Connector (OSTI)

Voltage sensing using helically coiled lengths of thermally poled twin-hole silica optical fibre is presented. Lab accuracy test results showing good linearity and signal to noise...

Michie, Andrew M; Hambley, Philip; Bassett, Ian M; Haywood, John H; Henry, Peter; Ingram, John

225

Improving the Performance of Heat Insulation Polyurethane Foams by Silica Nanoparticles  

Science Journals Connector (OSTI)

Heat insulation polyurethane foam materials were doped by silica nano particles, ... , thermal and mechanical properties of polyurethane rigid foam were investigated. Thermal and mechanical properties were...

M. M. Alavi Nikje; A. Bagheri Garmarudi; M. Haghshenas…

2009-01-01T23:59:59.000Z

226

Evaluation of concrete structures affected by alkali-silica reaction and delayed ettringite formation.  

E-Print Network [OSTI]

??Alkali-silica reaction (ASR) and delayed ettringite formation (DEF) are expansive reactions that can lead to the premature deterioration of concrete structures. Both have been implicated… (more)

Giannini, Eric Richard

2012-01-01T23:59:59.000Z

227

Nondestructive evaluation of reinforced concrete structures affected by alkali-silica reaction and delayed ettringite formation.  

E-Print Network [OSTI]

??Alkali-silica reaction (ASR) and delayed ettringite formation (DEF) deterioration have been a problem for the concrete infrastructure in the state of Texas and around the… (more)

Kreitman, Kerry Lynn

2011-01-01T23:59:59.000Z

228

Decohesion Kinetics in Polymer Organic Solar Cells  

Science Journals Connector (OSTI)

Decohesion Kinetics in Polymer Organic Solar Cells ... We investigate the role of molecular weight (MW) of the photoactive polymer poly(3-hexylthiophene) (P3HT) on the temperature-dependent decohesion kinetics of bulk heterojunction (BHJ) organic solar cells (OSCs). ... fullerenes; solar cells; thin films; fracture; polymer ...

Christopher Bruner; Fernando Novoa; Stephanie Dupont; Reinhold Dauskardt

2014-11-04T23:59:59.000Z

229

Polymer combustion: effects of flame emissivity  

Science Journals Connector (OSTI)

...gas phase. Polymer combustion chemistry is modelled...investigating polymer combustion it has proven advantageous...properties and treat the heat flux from the ignition...luminous flames from hydrocarbon fuels, it is common...A (1999) Polymer combustion: effects of flame emissivity...

1999-01-01T23:59:59.000Z

230

Organosiloxane-grafted natural polymer coatings  

DOE Patents [OSTI]

A new family of polysaccharide graft polymers are provided as corrosion resistant coatings having antimicrobial properties which are useful on light metals such as aluminum, magnesium, zinc, steel and their alloys. Methods of making the polysaccharide graft polymers are also included. The methods of making the polysaccharide graft polymers involve reacting a polysaccharide source with an antimicrobial agent under conditions of hydrolysis-condensation.

Sugama, Toshifumi (Wading River, NY)

1998-01-01T23:59:59.000Z

231

Conjugated Polymer Energy Level Shifts in Lithium-Ion Battery Electrolytes  

Science Journals Connector (OSTI)

Conjugated Polymer Energy Level Shifts in Lithium-Ion Battery Electrolytes ... By comparing the data obtained in the different systems, it is found that the IPs of the conjugated polymer films determined by conventional CV (IPC) can be correlated with UPS-measured HOMO energy levels (EH,UPS) by the relationship EH,UPS = (1.14 ± 0.23) × qIPC + (4.62 ± 0.10) eV, where q is the electron charge. ...

Charles Kiseok Song; Brian J. Eckstein; Teck Lip Dexter Tam; Lynn Trahey; Tobin J. Marks

2014-10-20T23:59:59.000Z

232

FOR STIMULI-RESPONSIVE POLYMERS WITH ENHANCED EFFICIENCY IN RESERVOIR RECOVERY PROCESSES  

SciTech Connect (OSTI)

To date, our synthetic research efforts have been focused on the development of stimuli-responsive water-soluble polymers designed for use in enhanced oil recovery (EOR) applications. These model systems are structurally tailored for potential application as viscosifiers and/or mobility control agents for secondary and tertiary EOR methods. The following report discloses the progress of our ongoing research of polyzwitterions, polymers derived from monomers bearing both positive and negative charges, that show the ability to sustain or increase their hydrodynamic volume (and thus, solution viscosity) in the presence of electrolytes. Such polymers appear to be well-suited for use under conditions similar to those encountered in EOR operations. Additionally, we disclose the synthesis and characterization of a well-defined set of polyacrylamide (PAM) homopolymers that vary by MW. The MW of the PAM samples is controlled by addition of sodium formate to the polymerization medium as a conventional chain transfer agent. Data derived from polymer characterization is used to determine the kinetic parameter C{sub CT}, the chain transfer constant to sodium formate under the given polymerization conditions. The PAM homopolymer series will be employed in future set of experiments designed to test a simplified intrinsic viscosity equation. The flow resistance of a polymer solution through a porous medium is controlled by the polymer's hydrodynamic volume, which is strongly related to it's intrinsic viscosity. However, the hydrodynamic volume of a polymer molecule in an aqueous solution varies with fluid temperature, solvent composition, and polymer structure. This report on the theory of polymer solubility accentuates the importance of developing polymer solutions that increase in intrinsic viscosity when fluid temperatures are elevated above room conditions. The intrinsic viscosity response to temperature and molecular weight variations of three polymer solutions verified the modeling capability of a simplified intrinsic viscosity equation. These results imply that the simplified intrinsic viscosity equation is adequate in modeling polymer coil size response to solvent composition, temperature and polymer molecular weight. The equation can be used to direct efforts to produce superior polymers for mobility control during flooding of reservoirs at elevated temperatures.

Charles McCormick; Roger Hester

2002-04-29T23:59:59.000Z

233

Enhanced photophysics of conjugated polymers  

DOE Patents [OSTI]

A particulate fluorescent conjugated polymer surfactant complex and method of making and using same. The particles are between about 15 and about 50 nm and when formed from a lipsome surfactant have a charge density similar to DNA and are strongly absorbed by cancer cells.

Chen, Liaohai (Darien, IL)

2007-06-12T23:59:59.000Z

234

POLYMER FEEDSTOCK MADE FROM BIOMASS  

Science Journals Connector (OSTI)

Method effectively converts fructose to 5-hydroxymethylfurfural ... Researchers at the University of Wisconsin, Madison, have developed a selective method for converting fructose to 5-hydroxymethylfurfural (HMF), a compound that could serve as a key intermediate for manufacturing polymers, pharmaceuticals, and other valuable products ( Science 2006, 312 , 1933). ...

2006-07-03T23:59:59.000Z

235

Friction between Ring Polymer Brushes  

E-Print Network [OSTI]

Friction between ring-polymer brushes at melt densities sliding past each other are studied using extensive course-grained molecular dynamics simulations and scaling arguments, and the results are compared to the friction between linear-polymer brushes. We show that for a velocity range spanning over three decades, the frictional forces measured for ring-polymer brushes are half the corresponding friction in case of linear brushes. In the linear-force regime, the weak inter-digitation of two ring brushes compared to linear brushes also leads to a lower number of binary collisions between the monomers of opposing brushes. At high velocities, where the thickness of the inter-digitation layer between two opposing brushes is on the order monomer size regardless of brush topology, stretched segments of ring polymers take a double-stranded conformation. As a result, monomers of the double-stranded segments collide less with the monomers of the opposing ring brush even though a similar number of monomers occupies the inter-digitation layer for ring and linear-brush bilayers. The numerical data obtained from our simulations is consistent with the proposed scaling analysis. Conformation-dependent frictional reduction observed in ring brushes can have important consequences in non-equilibrium bulk systems.

A. Erbas; J. Paturej

2015-01-07T23:59:59.000Z

236

Conducting Polymer Devices for Bioelectronics  

E-Print Network [OSTI]

signals recording. Organic electrochemical transistors (OECTs) represent a step beyond conducting polymer a far superior signal-to-noise- ratio (SNR) compared to electrodes. The high SNR of the OECT recordings and contamination. The use of an organic electrochemical transistor for detection of lactate by integration

Paris-Sud XI, Université de

237

Ultrafast laser induced electronic and structural modifications in bulk fused silica  

SciTech Connect (OSTI)

Ultrashort laser pulses can modify the inner structure of fused silica, generating refractive index changes varying from soft positive (type I) light guiding forms to negative (type II) values with void presence and anisotropic sub-wavelength modulation. We investigate electronic and structural material changes in the type I to type II transition via coherent and incoherent secondary light emission reflecting free carrier behavior and post-irradiation material relaxation in the index change patterns. Using phase contrast microscopy, photoluminescence, and Raman spectroscopy, we determine in a space-resolved manner defect formation, redistribution and spatial segregation, and glass network reorganization paths in conditions marking the changeover between type I and type II photoinscription regimes. We first show characteristic patterns of second harmonic generation in type I and type II traces, indicating the collective involvement of free carriers and polarization memory. Second, incoherent photoemission from resonantly and non-resonantly excited defect states reveals accumulation of non-bridging oxygen hole centers (NBOHCs) in positive index domains and oxygen deficiency centers (ODCs) with O{sub 2}{sup ?} ions segregation in void-like regions and in the nanostructured domains, reflecting the interaction strength. Complementary Raman investigations put into evidence signatures of the different environments where photo-chemical densification (bond rearrangements) and mechanical effects can be indicated. NBOHCs setting in before visible index changes serve as precursors for subsequent compaction build-up, indicating a scenario of cold, defect-assisted densification for the soft type I irradiation regime. Additionally, we observe hydrodynamic effects and severe bond-breaking in type II zones with indications of phase transition. These observations illuminate densification paths in fused silica in low power irradiation regimes, and equally in energetic ranges, characterized by the onset of thermo-mechanical effects.

Mishchik, K.; D'Amico, C.; Velpula, P. K.; Mauclair, C.; Boukenter, A.; Ouerdane, Y.; Stoian, R. [Laboratoire Hubert Curien, UMR 5516 CNRS, Université de Lyon, Université Jean Monnet, 42000 Saint Etienne (France)] [Laboratoire Hubert Curien, UMR 5516 CNRS, Université de Lyon, Université Jean Monnet, 42000 Saint Etienne (France)

2013-10-07T23:59:59.000Z

238

Study on separation of platinum group metals from high level liquid waste using macroporous (MOTDGA-TOA)/SiO{sub 2}-P silica-based absorbent  

SciTech Connect (OSTI)

The recovery of platinum group metals (PGMs) from high level liquid waste (HLLW) by macroporous silica-based adsorbent, (MOTDGA-TOA)/SiO{sub 2}-P has been developed by impregnating two extractants of N,N'-dimethyl-N,N'-di-n-octyl-thio-diglycolamide (MOTDGA) and tri-n-octylamine (TOA) into a silica/polymer composite support (SiO{sub 2}-P). The adsorption of Ru(III), Rh(III) and Pd(II) have been investigated in simulated HLLW by batch method. The adsorbent has shown good uptake property for Pd(II). In addition, the combined use of MOTDGA and TOA improved the adsorption of Ru(III) and Rh(III) better than the individual use of them. The usability of adsorbent in radiation fields was further confirmed by irradiation experiments. The adsorbent remained to have the uptake capability for PGMs over the absorbed dose of 100 kGy, corresponding with one really adsorbed by the adsorbent, and showed good retention capability for Pd(II) even at the absorbed dose of 800 kGy. The chromatographic separation of metal ions was demonstrated with the adsorbent packed column, there is no influence of Re(VII) (instead of Tc) on the excellent separation behavior of Pd(II). (authors)

Ito, Tatsuya [Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Japan Atomic Energy Agency, Tokai-mura Naka-gun, Ibarak319-1195 (Japan); Kim, Seong-Yun; Xu, Yuanlai; Hitomi, Keitaro [Cyclotron and Radioisotope Center, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578 (Japan); Ishii, Keizo [Department of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Aoba 6-6, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579 (Japan); Nagaishi, Ryuji; Kimura, Takaumi [Japan Atomic Energy Agency, Tokai-mura Naka-gun, Ibarak319-1195 (Japan)

2013-07-01T23:59:59.000Z

239

Release mechanism utilizing shape memory polymer material  

DOE Patents [OSTI]

Microfabricated therapeutic actuators are fabricated using a shape memory polymer (SMP), a polyurethane-based material that undergoes a phase transformation at a specified temperature (Tg). At a temperature above temperature Tg material is soft and can be easily reshaped into another configuration. As the temperature is lowered below temperature Tg the new shape is fixed and locked in as long as the material stays below temperature Tg. Upon reheating the material to a temperature above Tg, the material will return to its original shape. By the use of such SMP material, SMP microtubing can be used as a release actuator for the delivery of embolic coils through catheters into aneurysms, for example. The microtubing can be manufactured in various sizes and the phase change temperature Tg is determinate for an intended temperature target and intended use.

Lee, Abraham P. (Walnut Creek, CA); Northrup, M. Allen (Berkeley, CA); Ciarlo, Dino R. (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA); Benett, William J. (Livermore, CA)

2000-01-01T23:59:59.000Z

240

Interfacial Widths of Conjugated Polymer Bilayers  

SciTech Connect (OSTI)

The interfaces of conjugated polyelectrolyte (CPE)/poly[2-methoxy-5-(2{prime}-ethylhexyloxy)-p-phenylene vinylene] (MEH-PPV) bilayers cast from differential solvents are shown by resonant soft X-ray reflectivity (RSoXR) to be very smooth and sharp. The chemical interdiffusion due to casting is limited to less than 0.6 nm, and the interface created is thus nearly 'molecularly' sharp. These results demonstrate for the first time and with high precision that the nonpolar MEH-PPV layer is not much disturbed by casting the CPE layer from a polar solvent. A baseline is established for understanding the role of interfacial structure in determining the performance of CPE-based polymer light-emitting diodes. More broadly, we anticipate further applications of RSoXR as an important tool in achieving a deeper understanding of other multilayer organic optoelectronic devices, including multilayer photovoltaic devices.

NCSU; UC Berkeley; UCSB; Advanced Light Source; Garcia, Andres; Yan, Hongping; Sohn, Karen E.; Hexemer, Alexander; Nguyen, Thuc-Quyen; Bazan, Guillermo C.; Kramer, Edward J.; Ade, Harald

2009-08-13T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Thermal annealing of laser damage precursors on fused silica surfaces  

SciTech Connect (OSTI)

Previous studies have identified two significant precursors of laser damage on fused silica surfaces at fluenes below {approx} 35 J/cm{sup 2}, photoactive impurities in the polishing layer and surface fractures. In the present work, isothermal heating is studied as a means of remediating the highly absorptive, defect structure associated with surface fractures. A series of Vickers indentations were applied to silica surfaces at loads between 0.5N and 10N creating fracture networks between {approx} 10{micro}m and {approx} 50{micro}m in diameter. The indentations were characterized prior to and following thermal annealing under various times and temperature conditions using confocal time-resolved photo-luminescence (CTP) imaging, and R/1 optical damage testing with 3ns, 355nm laser pulses. Significant improvements in the damage thresholds, together with corresponding reductions in CTP intensity, were observed at temperatures well below the glass transition temperature (T{sub g}). For example, the damage threshold on 05.N indentations which typically initiates at fluences <8 J/cm{sup 2} could be improved >35 J/cm{sup 2} through the use of a {approx} 750 C thermal treatment. Larger fracture networks required longer or higher temperature treatment to achieve similar results. At an annealing temperature > 1100 C, optical microscopy indicates morphological changes in some of the fracture structure of indentations, although remnants of the original fracture and significant deformation was still observed after thermal annealing. This study demonstrates the potential of using isothermal annealing as a means of improving the laser damage resistance of fused silica optical components. Similarly, it provides a means of further understanding the physics associated with optical damage and related mitigation processes.

Shen, N; Miller, P E; Bude, J D; Laurence, T A; Suratwala, T I; Steele, W A; Feit, M D; Wang, L L

2012-03-19T23:59:59.000Z

242

Chapter Three - Crowding in Polymer–Nanoparticle Mixtures  

Science Journals Connector (OSTI)

Abstract The cell nucleus is a highly crowded environment, filled with a multicomponent, polydisperse mixture of biopolymers and nuclear bodies dispersed in a viscous solvent. With volume fractions approaching 20%, excluded-volume interactions play a key role in determining the structure, dynamics, and function of macromolecules in vivo. Under such constraints, the ensembles of macromolecular conformations can differ substantially from those prevailing in dilute solutions. Crowding thus can affect protein and RNA folding, conformational stability, and reaction kinetics, as well as phase stability of macromolecular mixtures. From the perspective of soft matter physics, this chapter reviews recent studies on crowding in polymer–nanoparticle mixtures, seeking to demonstrate the utility of simple physical models for addressing challenging issues in cell biology. The focus is on applications of free-volume theory and Monte Carlo simulation, based on geometrical models of polymers as fluctuating spheres or ellipsoids. Ideal polymer coils respond to hard-sphere crowding agents by compactifying, reducing their radius of gyration, and becoming more spherical. At sufficiently high concentrations, polymers and crowders phase-separate. The goal of this review is to identify universal principles governing macromolecular crowding and to establish a general framework for future explorations of more realistic models that may include nonsteric (e.g., electrostatic) interactions.

Alan R. Denton

2014-01-01T23:59:59.000Z

243

What determines the mobility of charge carriers in conjugated polymers?  

Science Journals Connector (OSTI)

...assume that, in principle, transport is fast...electroreflection method, Weiser Moller...doping. The latter method implies the introduction...able to recover the basic features of charge...relevant for organic photovoltaic devices, because...transport. The method of choice is radiation-induced...

2007-01-01T23:59:59.000Z

244

Chemical treatment for silica-containing glass surfaces  

DOE Patents [OSTI]

Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditions. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating. 11 figs.

Grabbe, A.; Michalske, T.A.; Smith, W.L.

1998-04-07T23:59:59.000Z

245

Chemical treatment for silica-containing glass surfaces  

DOE Patents [OSTI]

Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditions. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating.

Grabbe, Alexis (Albuquerque, NM); Michalske, Terry Arthur (Cedar Crest, NM); Smith, William Larry (Albuquerque, NM)

1998-01-01T23:59:59.000Z

246

Chemical treatment for silica-containing glass surfaces  

DOE Patents [OSTI]

Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditons. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating.

Grabbe, Alexis (Albuquerque, NM); Michalske, Terry Arthur (Cedar Crest, NM); Smith, William Larry (Albuquerque, NM)

1999-01-01T23:59:59.000Z

247

Chemical treatment for silica-containing glass surfaces  

DOE Patents [OSTI]

Dehydroxylated, silica-containing, glass surfaces are known to be at least partially terminated by strained siloxane rings. According to the invention, a surface of this kind is exposed to a selected silane compound or mixture of silane compounds under reaction-promoting conditions. The ensuing reaction results in opening of the strained siloxane rings, and termination of surface atoms by chemical species, such as organic or organosilicon species, having desirable properties. These species can be chosen to provide qualities such as hydrophobicity, or improved coupling to a polymeric coating.

Grabbe, Alexis (Albuquerque, NM); Michalske, Terry Arthur (Cedar Crest, NM); Smith, William Larry (Albuquerque, NM)

1999-01-01T23:59:59.000Z

248

Selective separation of Eu{sup 3+} using polymer-enhanced ultrafiltration  

SciTech Connect (OSTI)

A process to selectively remove {sup 241}Am from liquid radioactive waste was investigated as an actinide separation method applicable to Hanford and other waste sites. The experimental procedures involved removal of Eu, a nonradioactive surrogate for Am, from aqueous solutions at pH 5 using organic polymers in conjunction with ultrafiltration. Commercially available polyacrylic acid (60,000 MW) and Pacific Northwest Laboratory`s (PNL) synthesized E3 copolymer ({approximately}10,000 MW) were tested. Test solutions containing 10 {mu}g/mL of Eu were dosed vath each polymer at various concentrations in order to bind Eu (i.e., by complexation and/or cation exchange) for subsequent rejection by an ultrafiltration coupon. Test solutions were filtered with and without polymer to determine if enhanced Eu separation could be achieved from polymer treatment. Both polymers significantly increased Eu removal. Optimum concentrations were 20 {mu}g/mL of polyacrylic acid and 100 {mu}g/mL of E3 for 100% Eu rejection by the Amicon PM10 membrane at 55 psi. In addition to enhancement of removal, the polymers selectively bound Eu over Na, suggesting that selective separation of Eu was possible. This suggests that polymer-enhanced ultrafiltration is a potential process for separation of {sup 241}Am from Hanford tank waste, further investigation of binding agents and membranes effective under very alkaline and high ionic strength is warranted. This process also has potential applications for selective separation of toxic metals from industrial process streams.

Norton, M.V.

1994-03-01T23:59:59.000Z

249

Stress dependent activation entropy for dynamic fatigue of pristine silica optical fibers  

E-Print Network [OSTI]

Subcritical crack growth in fused silica is treated as a stress assisted chemical reaction between water distilled water and pH 7 buffer solution, and the results are found to be similar. The fatigue parameters to the barrier height. The results show subcritical crack growth in high strength silica is dominated by entropy

Matthewson, M. John

250

Synthesis of highly ordered mesoporous silica materials using sodium silicate and amphiphilic block copolymers  

E-Print Network [OSTI]

Synthesis of highly ordered mesoporous silica materials using sodium silicate and amphiphilic block. Pinnavaia and coworkers6 have reported the synthesis of MSU-X mesoporous materials with several non- ionic and cowork- ers7 have reported the synthesis of SBA mesoporous silica materials, which have well

Kim, Ji Man

251

Glycine and lysine adsorption and reactivity on the surface of amorphous silica  

Science Journals Connector (OSTI)

...J., Fricke, J. (1997): Raman spectroscopy on silica aerogels. J. Non-Cryst. Solids , 120 , 294-298. Rimola, A...J., Fricke, J. (1997): Raman spectroscopy on silica aerogels. J. Non-Cryst. Solids, 120, 294-298. Rimola, A...

Lorenzo Stievano; Ling Yu Piao; Irène Lopes; Ming Meng; Dominique Costa; Jean-François Lambert

252

Hybrid Silica-PVA Nanofibers via Sol-Gel Electrospinning Tahira Pirzada,,  

E-Print Network [OSTI]

Hybrid Silica-PVA Nanofibers via Sol-Gel Electrospinning Tahira Pirzada,,§ Sara A. Arvidson,,§ Carl: We report on the synthesis of poly(vinyl alcohol) (PVA)-silica hybrid nanofibers via sol-gel electro is under- taken and reveals a composition window in which defect-free hybrid nanofibers with diameters

Khan, Saad A.

253

Integrated Optical Orbital Angular Momentum Multiplexing Device using 3-D Waveguides and a Silica PLC  

E-Print Network [OSTI]

PLC Binbin Guan,1 Ryan P. Scott,1 Nicolas K. Fontaine,2 Tiehui Su,1 Carlo Ferrari,3 Mark Cappuzzo,3 on a silica planar lightwave circuit (PLC) coupled to a 3-D photonic circuit that efficiently generates planar lightwave circuit (PLC) with a silica 3-D PIC that supports up to 15 OAM modes, both TE and TM

Yoo, S. J. Ben

254

Friction and Heat Transfer Characteristics of Silica and CNT Nanofluids in a Tube Flow  

E-Print Network [OSTI]

Friction and Heat Transfer Characteristics of Silica and CNT Nanofluids in a Tube Flow MILIVOJE M@niu.edu * www.kostic.niu.edu Abstract: - An apparatus for exploring friction and heat transfer characteristics flow. Initial turbulent friction and heat transfer measurements for silica and carbon nanotube (CNT

Kostic, Milivoje M.

255

Sorption and Diffusion of Simple Paraffins in Silica-Alumina Cracking Catalyst  

Science Journals Connector (OSTI)

...Paraffins in Silica-Alumina Cracking Catalyst R. M. Barrer T. Gabor Sorption and...propane in the silica-alumina cracking catalyst previously employed in similar measurements...behaviour in the micropore structure of the catalyst, for the species studied. The ratio...

1960-01-01T23:59:59.000Z

256

Molten Gallium as a Catalyst for the Large-Scale Growth of Highly Aligned Silica Nanowires  

E-Print Network [OSTI]

Molten Gallium as a Catalyst for the Large-Scale Growth of Highly Aligned Silica Nanowires Zheng a small size (5-100 nm in diameter), high melting point metal (such as gold and iron) catalyst particle as an effective catalyst for the large-scale growth of highly aligned, closely packed silica nanowire bunches

Wang, Zhong L.

257

Ethylenediamine at Air/Liquid and Air/Silica Interfaces: Protonation  

E-Print Network [OSTI]

surface and EDA protonated products at air/liquid interfaces. The SFG spectra of EDA adsorbedEthylenediamine at Air/Liquid and Air/Silica Interfaces: Protonation Versus Hydrogen BondingKa (HOSit)) is between the two pKa values of EDA (in the range of 7.56-10.71) at the air/silica interface

258

Developing a process for commercial silica production from Salton Sea brines  

SciTech Connect (OSTI)

The goal of this joint LLNL-CalEnergy project is to develop a method for precipitating marketable silica from spent Salton Sea Geothermal Field (SSGF) brines. Many markets for silica exist. We have initially targeted production of silica as a rubber additive. Silica reinforced rubber gives tires less rolling resistance, greater tear strength, and better adhesion to steel belts. Previous silica precipitates produced by CalEnergy from Salton Sea brines were not suitable as rubber additives. They did not to disperse well in the rubber precursors and produced inferior rubber. CalEnergy currently minimizes silica scaling in some of their production facilities by acidifying the brine pH. The rate of silica precipitation slows down as the pH is lowered, so that energy extraction and brine reinfection are possible without unacceptable amounts of scaling even with more than 700 ppm SiO{sub 2} in solution. We are adding a step in which a small amount of base is added to the acidified brine to precipitate silica before reinfection. By carefully controlling the type, rate, and amount of base addition, we can optimize the properties of the precipitate to approach those of an ideal rubber additive.

Bourcier, W; McCutcheon, M; Leif, R; Bruton, C

2000-09-25T23:59:59.000Z

259

Modulating DNA adsorption on silica beads using an electrical switchw Oren Z. Gallb  

E-Print Network [OSTI]

use electrolysis of water to alter pH in a packed bed of silica beads and switch the silica bead electrolysis of water.20,21 The two gold electrodes (200 mm wide) were 1000 mm apart from each other, higher voltage introduces more electrolysis of water which changes the pH more rapidly. However, we found

Lu, Chang

260

The onset of optical breakdown in KrF-laser-irradiated silica glass surfaces  

E-Print Network [OSTI]

A synthetic fused silica obtained from Tosoh SGM Co., ESL-1000 (OH % 1200 wt. ppm), with a thick- ness of 2 mmThe onset of optical breakdown in KrF-laser-irradiated silica glass surfaces Y. Kawaguchia,* , A Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5, 1

Dickinson, J. Thomas

Note: This page contains sample records for the topic "determination silica polymer" 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

The effect of silica nanoparticle-modified surfaces on cell morphology, cytoskeletal organization and function  

E-Print Network [OSTI]

The effect of silica nanoparticle-modified surfaces on cell morphology, cytoskeletal organization investigate the effect of nanoparticle (NP) assemblies arranged on a flat substrate on cytoskeletal substrates were coated with monodispersed silica nanoparticles of 50, 100 and 300 nm in diameter. The impact

262

Surface Analysis of Silica Gel Particles after Mechanical Dry Coating with Magnesium Stearate  

E-Print Network [OSTI]

1 Surface Analysis of Silica Gel Particles after Mechanical Dry Coating with Magnesium Stearate particles (d50 = 55 µm) by coating with different mass ratios of magnesium stearate - MgSt2 (d50 = 4.6 µm Group). Keywords: AFM phase imaging, adhesion force, dry coating, silica, magnesium stearate. 1

Paris-Sud XI, Université de

263

DENSIFICATION AS THE ONLY MECHANISM AT STAKE DURING INDENTATION OF SILICA GLASS?  

E-Print Network [OSTI]

DENSIFICATION AS THE ONLY MECHANISM AT STAKE DURING INDENTATION OF SILICA GLASS? Vincent Keryvin1 mariette.nivard@univ-rennes1.fr, f jean-christophe.sangleboeuf@univ-rennes1.fr Keywords: Indentation; Glass; Densification; Plasticity; Imprint; Modeling; Finite-Element Analysis; Fused quartz Abstract. Silica glass

Brest, Université de

264

9 - Microporous silica membranes: fundamentals and applications in membrane reactors for hydrogen separation  

Science Journals Connector (OSTI)

Abstract: This chapter discusses the research and development of membrane reactors, incorporating microporous silica-based membranes, specifically for hydrogen production. Microporous silica membranes are first introduced alongside a discussion of relevant gas transport mechanisms, membrane performance parameters, membrane reactor designs and membrane reactor performance metrics. This is followed by an in-depth analysis of the various research investigations where silica membrane reactors have been used to produce hydrogen and/or syngas from hydrocarbon reforming reactions. Of particular importance here is the hydrothermal instability of silica-based membranes at the required operating temperatures and so the chapter closes by presenting the future research trends and industrial design challenges and considerations of silica-based membrane reactors.

S. Smart; J. Beltramini; J.C. Diniz da Costa; S.P. Katikaneni; T. Pham

2013-01-01T23:59:59.000Z

265

Preparation of dielectrics HR mirrors from colloidal oxide suspensions containing organic polymer binders  

SciTech Connect (OSTI)

Colloidal suspensions of oxides have been used to prepare dielectric HR (high reflective) mirrors, specifically for high power fusion case applications, on substrates up to 38 cm square using a meniscus coater. These coatings consist of porous quarterwave layers of alternating high and low refractive index oxides. Silica was used as the low index oxide and AlOOH, ZrO{sub 2}, or HfO{sub 2} as the high index material. Coatings were weak because of low particle-to-particle adhesion. Use of organic polymer binders in the high index component was found to increase strength, thereby improving the laser damage threshold and also reducing the number of layers required for 99% reflection due to increased refractive index.

Thomas, I.M.

1994-07-19T23:59:59.000Z

266

Nanoscale adhesion, friction and wear studies of biomolecules on silane polymer-coated silica and alumina-based surfaces  

Science Journals Connector (OSTI)

...M.A Elias, J Shapiro, L.J Brillson, B Bhushan, and S.C Lee2008Engineering...Elias, X Wen, J Shapiro, L.J Brillson, W Lu, and S.C Lee2008Detection of...Raton, FL:CRC Press Shapiro, J. , S. Gupta...Brillson, and S. C. Lee 2007 Challenges...

2009-01-01T23:59:59.000Z

267

Nanoscale adhesion, friction and wear studies of biomolecules on silane polymer-coated silica and alumina-based surfaces  

Science Journals Connector (OSTI)

...s10856-006-0657-x . Bhushan, B Handbook of micro/nano tribology...Publishers Bhushan, B Springer handbook of nanotechnology. 2nd edn...CO;2-Y . Lide, D.R CRC handbook of chemistry and physics. 83rd edn.2003Boca Raton...

2009-01-01T23:59:59.000Z

268

Improved Mobility Control for Carbon Dioxide (CO{sub 2}) Enhanced Oil Recovery Using Silica-Polymer-Initiator (SPI) Gels  

SciTech Connect (OSTI)

SPI gels are multi-component silicate based gels for improving (areal and vertical) conformance in oilfield enhanced recovery operations, including water-floods and carbon dioxide (CO{sub 2}) floods, as well as other applications. SPI mixtures are like-water when pumped, but form light up to very thick, paste-like gels in contact with CO{sub 2}. When formed they are 3 to 10 times stronger than any gelled polyacrylamide gel now available, however, they are not as strong as cement or epoxy, allowing them to be washed / jetted out of the wellbore without drilling. This DOE funded project allowed 8 SPI field treatments to be performed in 6 wells (5 injection wells and 1 production well) in 2 different fields with different operators, in 2 different basins (Gulf Coast and Permian) and in 2 different rock types (sandstone and dolomite). Field A was in a central Mississippi sandstone that injected CO{sub 2} as an immiscible process. Field B was in the west Texas San Andres dolomite formation with a mature water-alternating-gas miscible CO{sub 2} flood. Field A treatments are now over 1 year old while Field B treatments have only 4 months data available under variable WAG conditions. Both fields had other operational events and well work occurring before/ during / after the treatments making definitive evaluation difficult. Laboratory static beaker and dynamic sand pack tests were performed with Ottawa sand and both fields’ core material, brines and crude oils to improve SPI chemistry, optimize SPI formulations, ensure SPI mix compatibility with field rocks and fluids, optimize SPI treatment field treatment volumes and methods, and ensure that strong gels set in the reservoir. Field quality control procedures were designed and utilized. Pre-treatment well (surface) injectivities ranged from 0.39 to 7.9 MMCF/psi. The SPI treatment volumes ranged from 20.7 cubic meters (m{sup 3}, 5460 gallons/ 130 bbls) to 691 m{sup 3} (182,658 gallons/ 4349 bbls). Various size and types of chemical/ water buffers before and after the SPI mix ensured that pre-gelled SPI mix got out into the formation before setting into a gel. SPI gels were found to be 3 to 10 times stronger than any commercially available cross-linked polyacrylamide gels based on Penetrometer and Bulk Gel Shear Testing. Because of SPI’s unique chemistry with CO{sub 2}, both laboratory and later field tests demonstrated that multiple, smaller volume SPI treatments maybe more effective than one single large SPI treatment. CO{sub 2} injectivities in injection well in both fields were reduced by 33 to 70% indicating that injected CO{sub 2} is now going into new zones. This reduction has lasted 1+ year in Field A. Oil production increased and CO{sub 2} production decreased in 5 Field A production wells, offsets to Well #1 injector, for a total of about 2,250 m{sup 3} (600,000 gallons/ 14,250 bbls) of incremental oil production- a $140 / SPI bbl return. Treated marginal production well, Field A Well #2, immediately began showing increased oil production totaling 238 m{sup 3} (63,000 gallons/ 1500 BBLs) over 1 year and an immediate 81% reduced gas-oil ratio.

Oglesby, Kenneth

2014-01-31T23:59:59.000Z

269

The \\{LHCb\\} RICH silica aerogel performance with LHC data  

Science Journals Connector (OSTI)

In the \\{LHCb\\} experiment at the Large Hadron Collider, powerful charged particle identification is performed by Ring Imaging \\{CHerenkov\\} (RICH) technology. In order to cover the full geometric acceptance and the wide momentum range (1–100 GeV/c), two detectors with three Cherenkov radiators have been designed and installed. In the medium (10–40 GeV/c) and high (30–100 GeV/c) momentum ranges, gas radiators are used (C4F10 and CF4, respectively). In the low momentum range (1–10 GeV/c), pion, kaon and proton separation is performed with solid silica aerogel radiator. A set of 16 tiles, with large transverse dimensions of up to 200 × 200 mm 2 and nominal refractive index 1.03 have been produced and integrated in the detector. These tiles have excellent optical properties and homogeneity of the refractive index at the percent level within the tile. The first data collected at the LHC are used to investigate the behaviour of the RICH; preliminary results of the performance of silica aerogel are presented and discussed.

D.L. Perego

2011-01-01T23:59:59.000Z

270

Macroscopic Subdivision of Silica Aerogel Collectors for Sample Return Missions  

SciTech Connect (OSTI)

Silica aerogel collector tiles have been employed for the collection of particles in low Earth orbit and, more recently, for the capture of cometary particles by NASA's Stardust mission. Reliable, reproducible methods for cutting these and future collector tiles from sample return missions are necessary to maximize the science output from the extremely valuable embedded particles. We present a means of macroscopic subdivision of collector tiles by generating large-scale cuts over several centimeters in silica aerogel with almost no material loss. The cut surfaces are smooth and optically clear allowing visual location of particles for analysis and extraction. This capability is complementary to the smaller-scale cutting capabilities previously described [Westphal (2004), Ishii (2005a, 2005b)] for removing individual impacts and particulate debris in tiny aerogel extractions. Macroscopic cuts enable division and storage or distribution of portions of aerogel tiles for immediate analysis of samples by certain techniques in situ or further extraction of samples suited for other methods of analysis.

Ishii, H A; Bradley, J P

2005-09-14T23:59:59.000Z

271

Natural hydrous amorphous silica: Quantitation of network speciation and hydroxyl content by 29Si MAS NMR and vibrational spectroscopy  

Science Journals Connector (OSTI)

...included a volcanically derived silica coating on young basalt from Kilauea, Hawaii...sites, respectively. The Hawaiian silica coating and silicic acid samples displayed high...the structural Si-OH content of the coating was unusually high for a natural silica...

Steven M. Chemtob; George R. Rossman; Jonathan F. Stebbins

272

THE JOURNAL OF CHEMICAL PHYSICS 140, 224502 (2014) Search for a liquid-liquid critical point in models of silica  

E-Print Network [OSTI]

from pure sil- ica are widely used by the telecommunications industry and, because silica and silicates in models of silica Erik Lascaris,1 Mahin Hemmati,2 Sergey V. Buldyrev,3 H. Eugene Stanley,1 and C. Austen indicated the possible existence of a liquid-liquid critical point (LLCP) in models of silica at high

Stanley, H. Eugene

273

Aluminum and silica intake in drinking water and the risk of Alzheimer's disease or cognitive decline: findings of the  

E-Print Network [OSTI]

Aluminum and silica intake in drinking water and the risk of Alzheimer's disease or cognitive,2 , Commenges Daniel1,2 , Helmer Catherine2,3 , Jean-François Dartigues2,3 . Abbreviations: Al, Aluminum; AD, Alzheimer's Disease; MMSE, Mini Mental State Examination; Si, Silica Running head: Aluminum, silica in water

Paris-Sud XI, Université de

274

Internal dissipation of a polymer  

SciTech Connect (OSTI)

The dynamics of flexible polymer molecules are often assumed to be governed by hydrodynamics of the solvent. However there is considerable evidence that internal dissipation of a polymer contributes as well. Here we investigate the dynamics of a single chain in the absence of solvent to characterize the nature of this internal friction. We model the chains as freely hinged but with localized bond angles and threefold symmetric dihedral angles. We show that the damping is close but not identical to Kelvin damping, which depends on the first temporal and second spatial derivative of monomer position. With no internal potential between monomers, the magnitude of the damping is small for long wavelengths and weakly damped oscillatory time dependent behavior is seen for a large range of spatial modes. When the size of the internal potential is increased, such oscillations persist, but the damping becomes larger. However underdamped motion is present even with quite strong dihedral barriers for long enough wavelengths.

Deutsch, J. M. [Department of Physics, University of California, Santa Cruz, California 95064 (United States)

2010-06-15T23:59:59.000Z

275

Polymer system for gettering hydrogen  

DOE Patents [OSTI]

A novel composition comprising organic polymer molecules having carbon-carbon double bonds, for removing hydrogen from the atmosphere within enclosed spaces. Organic polymers molecules containing carbon-carbon double bonds throughout their structures, preferably polybutadiene, polyisoprene and derivatives thereof, intimately mixed with an insoluble catalyst composition, comprising a hydrogenation catalyst and a catalyst support, preferably Pd supported on carbon, provide a hydrogen getter composition useful for removing hydrogen from enclosed spaces even in the presence of contaminants such as common atmospheric gases, water vapor, carbon dioxide, ammonia, oil mists, and water. The hydrogen getter composition disclosed herein is particularly useful for removing hydrogen from enclosed spaces containing potentially explosive mixtures of hydrogen and oxygen.

Shepodd, Timothy Jon (330 Thrasher Ave., Livermore, Alameda County, CA 94550); Whinnery, LeRoy L. (4929 Julie St., Livermore, Alameda County, CA 94550)

2000-01-01T23:59:59.000Z

276

Polymer formulations for gettering hydrogen  

DOE Patents [OSTI]

A novel composition comprising organic polymer molecules having carbon-carbon double bonds, for removing hydrogen from the atmosphere within enclosed spaces. Organic polymers molecules containing carbon-carbon double bonds throughout their structures, preferably polybutadiene, polyisoprene and derivatives thereof, intimately mixed with an insoluble catalyst composition, comprising a hydrogenation catalyst and a catalyst support, preferably Pd supported on carbon, provide a hydrogen getter composition useful for removing hydrogen from enclosed spaces even in the presence of contaminants such as common atmospheric gases, water vapor, carbon dioxide, ammonia, oil mists, and water. The hydrogen getter composition disclosed herein is particularly useful for removing hydrogen from enclosed spaces containing potentially explosive mixtures of hydrogen and oxygen.

Shepodd, Timothy Jon (Livermore, CA); Whinnery, LeRoy L. (Livermore, CA)

1998-11-17T23:59:59.000Z

277

Electrically conductive polymer concrete coatings  

DOE Patents [OSTI]

A sprayable electrically conductive polymer concrete coating for vertical and overhead applications is described. The coating is permeable yet has low electrical resistivity (<10 ohm-cm), good bond strength to concrete substrates, and good weatherability. A preferred formulation contains about 60 wt% calcined coke breeze, 40 wt% vinyl ester resin with 3.5 wt% modified bentonite clay. Such formulations apply evenly and provide enough rigidity for vertical or overhead structures so there is no drip or sag. 4 tabs.

Fontana, J.J.; Elling, D.; Reams, W.

1988-05-26T23:59:59.000Z

278

Diamond turning of thermoplastic polymers  

SciTech Connect (OSTI)

Single point diamond turning studies were made using a series of thermoplastic polymers with different glass transition temperatures. Variations in surface morphology and surface roughness were observed as a function of cutting speed. Lower glass transition temperatures facilitate smoother surface cuts and better surface finish. This can be attributed to the frictional heating that occurs during machining. Because of the very low glass transition temperatures in polymeric compared to inorganic glasses, the precision machining response can be very speed sensitive.

Smith, E.; Scattergood, R.O.

1988-12-01T23:59:59.000Z

279

Electrically conductive polymer concrete coatings  

DOE Patents [OSTI]

A sprayable electrically conductive polymer concrete coating for vertical d overhead applications is described. The coating is permeable yet has low electrical resistivity (<10 ohm-cm), good bond strength to concrete substrates, and good weatherability. A preferred formulation contains about 60 wt % calcined coke breeze, 40 wt % vinyl ester with 3.5 wt % modified bentonite clay. Such formulations apply evenly and provide enough rigidity for vertical or overhead structures so there is no drip or sag.

Fontana, Jack J. (Shirley, NY); Elling, David (Centereach, NY); Reams, Walter (Shirley, NY)

1990-01-01T23:59:59.000Z

280

Solid-polymer-electrolyte fuel cells  

SciTech Connect (OSTI)

A transport model for polymer electrolytes is presented, based on concentrated solution theory and irreversible thermodynamics. Thermodynamic driving forces are developed, transport properties are identified and experiments devised. Transport number of water in Nafion 117 membrane is determined using a concentration cell. It is 1.4 for a membrane equilibrated with saturated water vapor at 25{degrees}C, decreases slowly as the membrane is dehydrated, and falls sharply toward zero as the water content approaches zero. The relation between transference number, transport number, and electroosmotic drag coefficient is presented, and their relevance to water-management is discussed. A mathematical model of transport in a solid-polymer-electrolyte fuel cell is presented. A two-dimensional membrane-electrode assembly is considered. Water management, thermal management, and utilization of fuel are examined in detail. The membrane separators of these fuel cells require sorbed water to maintain conductivity; therefore it is necessary to manage the water content in membranes to ensure efficient operation. Water and thermal management are interrelated. Rate of heat removal is shown to be a critical parameter in the operation of these fuel cells. Current-voltage curves are presented for operation on air and reformed methanol. Equations for convective diffusion to a rotating disk are solved numerically for a consolute point between the bulk concentration and the surface. A singular-perturbation expansion is presented for the condition where the bulk concentration is nearly equal to the consolute-point composition. Results are compared to Levich`s solution and analysis.

Fuller, T.F.

1992-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Protective properties of conversional polymer coatings  

SciTech Connect (OSTI)

In recent years, much attention has been devoted to the development of conversional polymer coatings deposited from aqueous solutions. A distinctive feature of such coatings is that their deposition occurs at the expense of the energy of chemical reactions on the surface of the treated metal. {open_quotes}Amchem,{close_quotes} {open_quotes}Oxy Metall,{close_quotes} and {open_quotes}Union Carbide Corp.{close_quotes} are leading company patentees in this field. The resistance of these coatings to the action of a salt mist lies within the range 16-500 h and depends on the nature of the latex and the composition of the compound. Below, we present results of an investigation of the protective properties of conversion polymeric coatings by different methods. The coatings were applied according to the technology developed at the Dnepropetrovsk Institute of Chemical Engineering. This technology differs from similar technologies used abroad by the utilization of products of large-scale chemical industrial production and specially synthesized stabilizers, which also play the role of cross-linking agents. The protective properties of conversional polymer coatings were studied using the pulse electrostatic method and also by simulated-service tests. As advantages of the electrostatic method over classical ac methods of corrosion testing, one can mention the possibilities of leveling the ohmic drop in a solution and measuring the values of the reaction resistance and the double-layer capacitance of a corroding electrode in the same test. The corrosion current was determined for given values of the reaction resistance and the anodic and cathodic Tafel constants, which can also be found from results of electrostatic measurements.

Panasenko, S.A.; Mark, L.I.; Grishchuk, V.I. [Dzerzhinskii Institute of Chemical Engineering, Dnepropetrovsk (Russian Federation)

1994-11-01T23:59:59.000Z

282

Meaning of reaction orders in polymer:fullerene solar cells  

Science Journals Connector (OSTI)

Nongeminate recombination in polymer:fullerene solar cells is frequently characterized using transient optoelectronic measurements that allow the determination of recombination rates, charge carrier lifetimes, and average charge carrier concentrations as a function of voltage. These data are often interpreted in terms of an empirical reaction order defining how recombination depends on measured charge density. In polymer:fullerene solar cells, the empirical reaction orders are often considerably larger than 2, which had previously been explained in terms of the nonlinear relationship between mobile and trapped charge carriers in the presence of an exponential tail of localized states. Here, we show that experimentally determined reaction orders depend not only on the shape of the density of states but also on the spatial distribution of carriers. In particular, in solar cells with small depletion regions due to small active layer thicknesses or due to large unintentional background doping of the polymers, the reaction order can assume values that are much larger than the value expected from the shape of the density of states alone.

Thomas Kirchartz and Jenny Nelson

2012-10-05T23:59:59.000Z

283

Electrochemical properties of Li ion polymer battery with gel polymer electrolyte based on polyurethane  

Science Journals Connector (OSTI)

Gel polymer electrolyte (GPE) was prepared using polyurethane acrylate as polymer host and its performance was evaluated. LiCoO2/GPE/graphite cells were prepared and their electrochemical performance as a functio...

H-S. Kim; G-Y. Choi; S-I. Moon; S-P. Kim

2003-06-01T23:59:59.000Z

284

Displacement Mechanism of Polymer Flooding by Molecular  

Science Journals Connector (OSTI)

Whether polymer flooding can enhance displacement efficiency or not is still a problem under debate. Laboratory experiment, numerical simulation and core data analysis are the commonly used means to study polymer flooding displacement efficiency. We discuss the limitations of these methods and employ molecular tribology to study the problem. The black–white ball action principle, i.e. the atom action model for describing the friction principle, is used to analyse the microscopic mechanism of oil displacement and describe the molecular interactions and displacement power during polymer flooding. Both tribology theory and dynamic rheological test show that molecular interactions during polymer flooding are bigger than that during water flooding. It is concluded that displacement efficiency of water flooding may be higher than that of polymer flooding at particular area; while polymer flooding can weaken the heterogeneity significantly, decrease ineffective injection and enhance the total displacement efficiency.

Yang Er-Long; Song Kao-Ping

2006-01-01T23:59:59.000Z

285

Tritium containing polymers having a polymer backbone substantially void of tritium  

DOE Patents [OSTI]

A radioluminescent light source comprises a solid mixture of a phosphorescent substance and a tritiated polymer. The solid mixture forms a solid mass having length, width, and thickness dimensions, and is capable of self-support. In one aspect of the invention, the phosphorescent substance comprises solid phosphor particles supported or surrounded within a solid matrix by a tritium containing polymer. The tritium containing polymer comprises a polymer backbone which is essentially void of tritium. 2 figs.

Jensen, G.A.; Nelson, D.A.; Molton, P.M.

1992-03-31T23:59:59.000Z

286

Structural Arrangements of Polymers Adsorbed at Nanostrings  

E-Print Network [OSTI]

We study ground states of a hybrid system consisting of a polymer and an attractive nanowire by means of computer simulations. Depending on structural and energetic properties of the substrate, we find different adsorbed polymer conformations, amongst which are spherical droplets attached to the wire and monolayer tubes surrounding it. We construct the complete conformational phase diagram and analyze in more detail particularly interesting polymer-tube conformations.

Thomas Vogel; Michael Bachmann

2011-03-09T23:59:59.000Z

287

Nanoscale molecularly imprinted polymers and method thereof  

DOE Patents [OSTI]

Nanoscale molecularly imprinted polymers (MIP) having polymer features wherein the size, shape and position are predetermined can be fabricated using an xy piezo stage mounted on an inverted microscope and a laser. Using an AMF controller, a solution containing polymer precursors and a photo initiator are positioned on the xy piezo and hit with a laser beam. The thickness of the polymeric features can be varied from a few nanometers to over a micron.

Hart, Bradley R. (Brentwood, CA); Talley, Chad E. (Brentwood, CA)

2008-06-10T23:59:59.000Z

288

Organosiloxane-grafted natural polymer coatings  

DOE Patents [OSTI]

A new family of polysaccharide graft polymers are provided as corrosion resistant coatings having antimicrobial properties which are useful on light metals such as aluminum, magnesium, zinc, steel and their alloys. Methods of making the polysaccharide graft polymers are also included. The methods of making the polysaccharide graft polymers involve reacting a polysaccharide source with an antimicrobial agent under conditions of hydrolysis-condensation. 17 figs.

Sugama, Toshifumi

1998-12-01T23:59:59.000Z

289

Transport characteristics across drum filter vents and polymer bags  

SciTech Connect (OSTI)

The rate at which hydrogen (H {sub 2}) or a volatile organic compound (VOC) exits a layer of confinement in a vented waste drum is proportional to the concentration difference across the layer. The proportionality constant is the gas transport characteristic. A series of transport experiments were conducted to determine H{sub 2} and VOC transport characteristics across different drum filter vents and polymer bags. This report reviews the methods and results of past investigators in defining transport characteristics across filter vents and polymer bags, describes the apparatus and procedures used in these experiments, compares the reported and estimated transport characteristics with earlier results, and discusses the impact of changing the transport characteristic values used in model calculations.

Liekhus, K.J.

1994-08-01T23:59:59.000Z

290

Polymer Electrolytes for Advanced Lithium Batteries | Department...  

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

Advanced Lithium Batteries Polymer Electrolytes for Advanced Lithium Batteries 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation...

291

ELECTROSPUN POLYMER-FIBER SOLAR CELL.  

E-Print Network [OSTI]

??A study of fabricating the first electrospun polymer-fiber solar cell with MEHPPV is presented. Motivation for the work and a brief history of solar cell… (more)

Nagata, Shinobu

2011-01-01T23:59:59.000Z

292

Graphene-based polymer waveguide polarizer  

Science Journals Connector (OSTI)

Planar-lightwave-circuit (PLC)-type graphene polarizers are fabricated by using a low loss optical polymer waveguide. The optical characteristics are investigated at a wavelength of...

Kim, Jin Tae; Choi, Choon-Gi

2012-01-01T23:59:59.000Z

293

Dynamics in Polymer | ornl.gov  

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

Neutron scattering characterizes dynamics in polymer family Agatha Bardoel - December 01, 2012 Interior of BASIS. Research Contact: Christine Gerstl Understanding the interplay...

294

Imaging Hydrated Microbial Extracellular Polymers: Comparative...  

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

dehydration-based sample preparation that resulted in the collapse of hydrated gel-like EPS into filamentous structures. Dehydration-induced polymer collapse can lead to...

295

Heat insulation layer of polymer composite material  

Science Journals Connector (OSTI)

A new heat insulation layer polymer composite material is developed, within whose composition there is foam polyurethane and basaltoplastic. Results are provided for...

G. P. Ponomareva; A. A. Artemenko; O. M. Sladkov…

2010-05-01T23:59:59.000Z

296

Efficient Polymer Solar Cells - Energy Innovation Portal  

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

Laboratory researchers have developed a process for producing more efficient polymer solar cells by increasing light absorption through a thin and uniform light-absorbing...

297

Plasma immersion ion implantation on polymers.  

E-Print Network [OSTI]

??The focus of this thesis is to achieve plasma based surface modification of polymers. Highly ionized carbon plasma was generated from a filtered cathodic arc… (more)

Sze, Jia Yin.

2010-01-01T23:59:59.000Z

298

Semi-Crystalline Polymers Semi-crystalline polymers, such as polyethylene and polypropylene are common  

E-Print Network [OSTI]

Semi-Crystalline Polymers Semi-crystalline polymers, such as polyethylene and polypropylene are common commercial materials used for consumer products. Polyethylene is the most widely used polymer due and processing conditions. Equistar, in Cincinnati, is the largest producer of polyethylene in the US and P

Beaucage, Gregory

299

SEC data for polymer 1-6: UV-vis spectra for polymer 1-6  

E-Print Network [OSTI]

for organic solar cells Eva Bundgaard a,b and Frederik C. Krebs a a Polymer Solar Cell Initiative, The Danish for these devices is summarized in the table below. IV-curve for the polymer 5 and PCBM: The photovoltaic studies of the device by a better overlap with the solar spectrum. The synthesis of low band gap polymers are however

300

EFFECTS OF TRITIUM GAS EXPOSURE ON ELECTRICALLY CONDUCTING POLYMERS  

SciTech Connect (OSTI)

Effects of beta (tritium) and gamma irradiation on the surface electrical conductivity of two types of conducting polymer films are documented to determine their potential use as a sensing and surveillance device for the tritium facility. It was shown that surface conductivity was significantly reduced by irradiation with both gamma and tritium gas. In order to compare the results from the two radiation sources, an approximate dose equivalence was calculated. The materials were also sensitive to small radiation doses (<10{sup 5} rad), showing that there is a measurable response to relatively small total doses of tritium gas. Spectroscopy was also used to confirm the mechanism by which this sensing device would operate in order to calibrate this sensor for potential use. It was determined that one material (polyaniline) was very sensitive to oxidation while the other material (PEDOT-PSS) was not. However, polyaniline provided the best response as a sensing material, and it is suggested that an oxygen-impermeable, radiation-transparent coating be applied to this material for future device prototype fabrication. A great deal of interest has developed in recent years in the area of conducting polymers due to the high levels of conductivity that can be achieved, some comparable to that of metals [Gerard 2002]. Additionally, the desirable physical and chemical properties of a polymer are retained and can be exploited for various applications, including light emitting diodes (LED), anti-static packaging, electronic coatings, and sensors. The electron transfer mechanism is generally accepted as one of electron 'hopping' through delocalized electrons in the conjugated backbone, although other mechanisms have been proposed based on the type of polymer and dopant [Inzelt 2000, Gerard 2002]. The conducting polymer polyaniline (PANi) is of particular interest because there are extensive studies on the modulation of the conductivity by changing either the oxidation state of the main backbone chain, or by protonation of the imine groups [de Acevedo, 1999]. There are several types of radiation sensors commercially available, including ionization chambers, geiger counters, proportional counters, scintillators and solid state detectors. Each type has advantages, although many of these sensors require expensive electronics for signal amplification, are large and bulky, have limited battery life or require expensive materials for fabrication. A radiation sensor constructed of a polymeric material could be flexible, light, and the geometry designed to suit the application. Very simple and inexpensive electronics would be necessary to measure the change in conductivity with exposure to radiation and provide an alarm system when a set change of conductivity occurs in the sensor that corresponds to a predetermined radiation dose having been absorbed by the polymer. The advantages of using a polymeric sensor of this type rather than those currently in use are the flexibility of sensor geometry and relatively low cost. It is anticipated that these sensors can be made small enough for glovebox applications or have the ability to monitor the air tritium levels in places where a traditional monitor cannot be placed. There have been a few studies on the changes in conductivity of polyaniline specifically for radiation detection [de Acevedo, 1999; Lima Pacheco, 2003], but there have been no reports on the effects of tritium (beta radiation) on conducting polymers, such as polyaniline or polythiophene. The direct implementation of conducting polymers as radiation sensor materials has not yet been commercialized due to differing responses with total dose, dose rate, etc. Some have reported a large increase in the surface conductivity with radiation dose while others report a marked decrease in conductive properties; these differing observations may reflect the competing mechanisms of chain scission and cross-linking. However, it is clear that the radiation dose effects on conducting polymers must be fully understood before these materials can be used

Kane, M.; Clark, E.; Lascola, R.

2009-12-16T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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.


301

Preparation of Activated Carbon and Silica Particles from Rice Straw  

Science Journals Connector (OSTI)

Lignocellulosic biomass, such as agricultural crop residues, forestry byproducts, and municipal waste, is a rich source of renewable energy and materials. ... The LH powders were dried in oven at 60 °C for 12 h, placed in a quartz tube (2 cm inner diameter), and then dried in a furnace (Mini-Mite, Lindberg/Blue) at 10 °C/min to 105 °C and held for 0.5 h. ... TEM samples were prepared by dispersing a small amount of AC and silica particles in water (?0.01 g/L) and sonicated (2510, Branson) for 60 min first, and then a drop of the sonicated suspension was placed onto a carbon grid and dried in air. ...

Sixiao Hu; You-Lo Hsieh

2014-02-21T23:59:59.000Z

302

Hydrogen and oxygen adsorption stoichiometries on silica supported ruthenium nanoparticles  

SciTech Connect (OSTI)

Treatment under H{sub 2} at 300 C of Ru(COD)(COT) dispersed on silica yields 2 nm ruthenium nanoparticles, [Ru{sub p}/SiO{sub 2}], according to EXAFS, HRTEM and XPS. H{sub 2} adsorption measurements on [Ru{sub p}/SiO{sub 2}] in the absence of O{sub 2} show that Ru particles adsorb up to ca. 2 H per surface ruthenium atoms (2H/Ru{sub s}) on various samples; this technique can therefore be used to measure the dispersion of Ru particles. In contrast, O{sub 2} adsorption on [Ru{sub p}/SiO{sub 2}] leads to a partial oxidation of the bulk at 25 C, to RuO{sub 2} at 200 C and to sintering upon further reduction under H{sub 2}, showing that O{sub 2} adsorption cannot be used to measure the dispersion of Ru particles.

Berthoud, Romain; Delichere, Pierre; Gajan, David; Lukens, Wayne; Pelzer, Katrin; Basset, Jean-Marie; Candy, Jean-Pierre; Coperet, Christophe

2008-12-01T23:59:59.000Z

303

Use of silica waste from the Cerro Prieto geothermal field as construction material  

SciTech Connect (OSTI)

The Cerro Prieto geothermal field generates 620 MW of electric power and in the process produces 11,000 tonnes of brine per hour that is disposed of in surface ponds. Approximately 1300 tonnes of silica waste is the residual product from this hourly production of brine. At present, there is no use for this waste silica. Some experimental work has been undertaken by CFE to utilize this waste silica such as for surfacing roads with a cement-silica mixture and making bricks with various additives. However, none of this research has been documented. Approximately two years ago, a joint USDOE/CFE research project was proposed to investigate the use of the waste silica. The proposal included using the silica mixed with asphalt and cement to produce a suitable road surfacing material, and to combine the silica with various additives to be used as bricks for low cost housing. It was thought, that the low specific gravity of the silica and the proposed mixtures would give the bricks a high insulating value (low-thermal conductivity), thus protecting the residents from high solar heating, typical of Baja California and the area around Mexicali. Finally, since the geothermal fields of the area extend into the Imperial Valley of California where 420 MW of geothermal power is generated, it was hoped that this research would also be applicable to the U.S. side of the border. Some attempt has been made by UNOCAL at their Imperial Valley plant (now owned by Magma Power) to use the waste silica stabilized with cement for roads and dikes around the plant.

Lund, J.W.; Boyd, T.; Monnie, D.

1995-02-01T23:59:59.000Z

304

Production of structures for microfluidics using polymer imprint techniques  

Science Journals Connector (OSTI)

We present a technology for the fabrication of three dimensional microfluidic channels in optically transparent substrates consisting of polymers with different properties. The microstructures are fabricated using polymer replication techniques with ... Keywords: Hot embossing, Micromechanisation, Micromoldin, Nanoimprint lithography, Polymers

C. A. Mills; E. Martinez; F. Bessueille; G. Villanueva; J. Bausells; J. Samitier; A. Errachid

2005-03-01T23:59:59.000Z

305

Systematic development of coarse-grained polymer models  

E-Print Network [OSTI]

The coupling between polymer models and experiments has improved our understanding of polymer behavior both in terms of rheology and dynamics of single molecules. Developing these polymer models is challenging because of ...

Underhill, Patrick Theodore

2006-01-01T23:59:59.000Z

306

Studies of Immobilized Homogeneous Metal Catalysts on Silica Supports  

SciTech Connect (OSTI)

The tethered, chiral, chelating diphosphine rhodium complex, which catalyzes the enantioselective hydrogenation of methyl-{alpha}-acetamidocinnamate (MAC), has the illustrated structure as established by {sup 31}P NMR and IR studies. Spectral and catalytic investigations also suggest that the mechanism of action of the tethered complex is the same as that of the untethered complex in solution. The rhodium complexes, [Rh(COD)H]{sub 4}, [Rh(COD){sub 2}]{sup +}BF{sub 4}{sup -}, [Rh(COD)Cl]{sub 2}, and RhCl{sub 3} {center_dot} 3H{sub 2}O, adsorbed on SiO{sub 2} are optimally activated for toluene hydrogenation by pretreatment with H{sub 2} at 200 C. The same complexes on Pd-SiO{sub 2} are equally active without pretreatments. The active species in all cases is rhodium metal. The catalysts were characterized by XPS, TEM, DRIFTS, and mercury poisoning experiments. Rhodium on silica catalyzes the hydrogenation of fluorobenzene to produce predominantly fluorocyclohexane in heptane and 1,2-dichloroethane solvents. In heptane/methanol and heptane/water solvents, hydrodefluorination to benzene and subsequent hydrogenation to cyclohexane occurs exclusively. Benzene inhibits the hydrodefluorination of fluorobenzene. In DCE or heptane solvents, fluorocyclohexane reacts with hydrogen fluoride to form cyclohexene. Reaction conditions can be chosen to selectively yield fluorocyclohexane, cyclohexene, benzene, or cyclohexane. The oxorhenium(V) dithiolate catalyst [-S(CH{sub 2}){sub 3}s-]Re(O)(Me)(PPh{sub 3}) was modified by linking it to a tether that could be attached to a silica support. Spectroscopic investigation and catalytic oxidation reactivity showed the heterogenized catalyst's structure and reactivity to be similar to its homogeneous analog. However, the immobilized catalyst offered additional advantages of recyclability, extended stability, and increased resistance to deactivation.

Keith James Stanger

2003-05-31T23:59:59.000Z

307

Effect of Optical Coating and Surface Treatments on Mechanical Loss in Fused Silica  

E-Print Network [OSTI]

We report on the mechanical loss in fused silica samples with various surface treatments and compare them with samples having an optical coating. Mild surface treatments such as washing in detergent or acetone were not found to affect the mechanical loss of flame-drawn fused silica fibers stored in air. However, mechanical contact (with steel calipers) significantly increased the loss. The application of a high-reflective optical coating of the type used for the LIGO test masses was found to greatly increase the mechanical loss of commercially polished fused silica microscope slides. We discuss the implications for the noise budget of interferometers.

Andri M. Gretarsson; Gregory M. Harry; Steven D. Penn; Peter R. Saulson; John J. Schiller; William J. Startin

1999-11-17T23:59:59.000Z

308

Polymers For Advanced Lithium Batteries | Department of Energy  

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

Polymers For Advanced Lithium Batteries Polymers For Advanced Lithium Batteries 2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and...

309

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles...  

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

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles High-Voltage Solid Polymer Batteries for Electric Drive Vehicles 2013 DOE Hydrogen and Fuel Cells Program and...

310

Polymers For Advanced Lithium Batteries | Department of Energy  

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

Polymers For Advanced Lithium Batteries Polymers For Advanced Lithium Batteries 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and...

311

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

High-Voltage Solid Polymer Batteries for Electric Drive Vehicles High-Voltage Solid Polymer Batteries for Electric Drive Vehicles 2012 DOE Hydrogen and Fuel Cells Program and...

312

Development of Polymer Electrolytes for Advanced Lithium Batteries...  

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

Development of Polymer Electrolytes for Advanced Lithium Batteries Development of Polymer Electrolytes for Advanced Lithium Batteries 2013 DOE Hydrogen and Fuel Cells Program and...

313

Fabrication and performance of polymer-nanocomposite anti-reflective...  

Office of Scientific and Technical Information (OSTI)

News, VA (United States) Design of polymer anti-reflective (AR) optical coatings for plastic substrates is challenging because polymers exhibit a relatively narrow range of...

314

Fiber-Reinforced Polymer Composites: Pursuing the Promise | Department...  

Energy Savers [EERE]

Fiber-Reinforced Polymer Composites: Pursuing the Promise Fiber-Reinforced Polymer Composites: Pursuing the Promise High-strength, lightweight advanced composites will deliver a...

315

Phosphate-Containing Polyethylene Glycol Polymers Prevent Lethal...  

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

Phosphate-Containing Polyethylene Glycol Polymers Prevent Lethal Sepsis by Multidrug-Resistant Pathogens. Phosphate-Containing Polyethylene Glycol Polymers Prevent Lethal Sepsis by...

316

Title: Pore formation in Polymer Electrolytes Abstract: Much of our ...  

E-Print Network [OSTI]

The efficient conversion of energy from one form to another, particularly solar, ... The polymer electrolytes in Polymer Electrolyte Membrane (PEM) fuel cells ...

317

Controlled Self Assembly of Conjugated Polymer Containing Block Copolymers  

E-Print Network [OSTI]

in dye/polymer blend photovoltaic cells. Advanced MaterialsA. J. , Polymer Photovoltaic Cells - Enhanced Efficiencies2-Layer Organic Photovoltaic Cell. Applied Physics Letters

McCulloch, Bryan

2012-01-01T23:59:59.000Z

318

azo dye polymer: Topics by E-print Network  

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

alignment 10 Solvent-enhanced dye diffusion in polymer thin films for polymer light-emitting diode application Engineering Websites Summary: Solvent-enhanced dye diffusion in...

319

Self-Assembly of Polymer Nano-Elements on Sapphire  

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

Self-Assembly of Polymer Nano-Elements on Sapphire Print Self-assembly of polymers promises to vastly improve the properties and manufacturing processes of nanostructured...

320

Haverford Researchers Create Carbon Dioxide-Separating Polymer  

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

Haverford College Researchers Create Carbon Dioxide-Separating Polymer Haverford College Researchers Create Carbon Dioxide-Separating Polymer August 1, 2012 | Tags: Basic Energy...

Note: This page contains sample records for the topic "determination silica polymer" 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

Structure-Function Relationships in Semiconducting Polymers for Organic Photovoltaics  

E-Print Network [OSTI]

properties for organic photovoltaics (OPVs). Space-chargePolymers for Organic Photovoltaics By David Fredric JoelPolymers for Organic Photovoltaics by David Fredric Joel

Kavulak, David Fredric Joel

2010-01-01T23:59:59.000Z

322

Low-pressure plasma-etching of bulk polymer materials using gas mixture of CF{sub 4} and O{sub 2}  

SciTech Connect (OSTI)

In this study, we have proposed a low-pressure reactive ion etching of bulk polymer materials with a gas mixture of CF{sub 4} and O{sub 2}, and have achieved precise fabrication of poly(methyl methacrylate) (PMMA) and perfluoroalkoxy (PFA) bulk polymer plates with high-aspect-ratio and narrow gap array structures, such as, pillar, frustum, or cone, on a nano/micro scale. The effects of the etching conditions on the shape and size of each pillar were evaluated by changing etching duration and the size/material of etching mask. The fabricated PMMA array structures indicate possibilities of optical waveguide and nanofiber array. PFA cone array structures showed super-hydrophobicity without any chemical treatments. Also, polystyrene-coated silica spheres were used as an etching mask for the pillar array structure formation to control the gap between pillars.

Nabesawa, Hirofumi [Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, Chiba, 263-8522 (Japan) [Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, Chiba, 263-8522 (Japan); Central Research Institute, Toyama Industrial Technology Center, Takaoka, 933-0981 (Japan); Hiruma, Takaharu; Seki, Minoru, E-mail: mseki@faculty.chiba-u.jp [Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, Chiba, 263-8522 (Japan)] [Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, Chiba, 263-8522 (Japan); Hitobo, Takeshi [Tateyama Machine Co. Ltd., Toyama, 930-1305 (Japan)] [Tateyama Machine Co. Ltd., Toyama, 930-1305 (Japan); Wakabayashi, Suguru [Tateyama Kagaku Industry Co. Ltd., Toyama, 930-1305 (Japan)] [Tateyama Kagaku Industry Co. Ltd., Toyama, 930-1305 (Japan); Asaji, Toyohisa [Tateyama Machine Co. Ltd., Toyama, 930-1305 (Japan) [Tateyama Machine Co. Ltd., Toyama, 930-1305 (Japan); Electronic-Mechanical Engineering Department, Oshima National College of Maritime Technology, Suo-Oshima, 742-2193 (Japan); Abe, Takashi [Department of Mechanical and Production Engineering, Graduate School of Science and Technology, Niigata University, Niigata, 950-2181 (Japan)] [Department of Mechanical and Production Engineering, Graduate School of Science and Technology, Niigata University, Niigata, 950-2181 (Japan)

2013-11-15T23:59:59.000Z

323

Electrophoretic NMR measurements of lithium transference numbers in polymer gel electrolytes  

SciTech Connect (OSTI)

Polymer gel electrolytes are of increasing interest for plastic lithium batteries largely because of their high room temperature conductivity. Several studies have probed their conductivity and electrochemical stability but very little work has been done related to lithium transference numbers. Lithium ion transference numbers, the net number of Faradays carried by lithium upon the passage of 1 Faraday of charge across a cell, are key figures of merit for any potential lithium battery electrolytes. The authors describe here their application of electrophoretic NMR (ENMR) to the determination of transference numbers of lithium ions in polymer gel electrolytes. Two types of polymer gel electrolytes were selected for this study: PAN/PC/EC/LiX and Kynar/PC/LiX. Results obtained for the two types of gels are compared and the effects of anion, polymer-ion interactions and ion-ion interactions on lithium transference numbers are discussed. Significant differences in the behavior of transference numbers with salt concentration are observed for the two types of gels. This may be due to the extent of interaction between the polymer and the ions. Implications for solid polymer electrolytes are discussed.

Dai, H.; Sanderson, S.; Davey, J.; Uribe, F.; Zawodzinski, T.A. Jr. [Los Alamos National Lab., NM (United States). Electronics Materials and Device Research Group

1997-05-01T23:59:59.000Z

324

Synthesis and characterization of self-assembling water-soluble polymers  

SciTech Connect (OSTI)

The synthesis is proposed of water-soluble vinyl and other polymers capable of self-assembly through hydrophobic bonding of pendent fluorocarbon and other hydrophobic groups. The self-assembly process will be studied by viscometry and dynamic viscoelasticity, and by static and dynamic light scattering. These investigations are aimed at identifying the structural features of polymers that are important in enhancing the viscosity of aqueous polymer solutions at very low polymer concentrations (< 1,000 ppm). The authors also initiate small angle neutron scattering (SANS) measurements aimed at the determination of the size of the fluorocarbon-containing hydrophobic aggregates. They will be interested in the degree of self assembly as a function of the type and length of the hydrophobic groups and of the type and length of the flexible spacer group linking the hydrophobic to the polymer backbone. The nature of the hydrophilic chain will also be of interest. Thus, they investigate a number of hydrophilic comonomers such as acrylamide, N-vinylpyrrolidone and anionic or cationic vinyl monomers. Surface interactions of these interesting copolymers will be studied by adsorption onto appropriate modified latex spheres. Finally, they propose to explore the synthesis of water-soluble polymers capable of self assembly through interactions of pendent polyanions and polycations.

Hogen-Esch, T.E.; Amis, E.J.

1992-05-01T23:59:59.000Z

325

Tandem Polymer Solar Cells Featuring a Spectrally Matched Low-Bandgap Polymer  

SciTech Connect (OSTI)

Tandem solar cells provide an effective way to harvest a broader spectrum of solar radiation by combining two or more solar cells with different absorption bands. However, for polymer solar cells, the performance of tandem devices lags behind single-layer solar cells mainly due to the lack of a suitable low-bandgap polymer. Here, we demonstrate highly efficient single and tandem polymer solar cells featuring a low-bandgap conjugated polymer (PBDTT-DPP: bandgap, {approx}1.44 eV). A single-layer device based on the polymer provides a power conversion efficiency of {approx}6%. When the polymer is applied to tandem solar cells, a power conversion efficiency of 8.62% is achieved, which is, to the best of our knowledge, the highest certified efficiency for a polymer solar cell to date.

Dou, L.; You, J.; Yang, J.; Chen, C. C.; He, Y.; Murase, S.; Moriarty, T.; Emery, K.; Li, G.; Yang, Y.

2012-03-01T23:59:59.000Z

326

Silica nanocasting of lyotropic surfactant phases and organized organic matter: material science or an analytical tool?  

Science Journals Connector (OSTI)

...of polymers, such as poly(ethylene oxide), poly(methyl methacrylate...relevant templates with a very low price, polymer dispersions or latexes...systems far beyond water: poly(ethylene-co-butylene)-b-poly(ethylene oxide) (KLE-polymers...

2006-01-01T23:59:59.000Z

327

Knot localization in adsorbing polymer rings  

E-Print Network [OSTI]

We study by Monte Carlo simulations a model of knotted polymer ring adsorbing onto an impenetrable, attractive wall. The polymer is described by a self-avoiding polygon (SAP) on the cubic lattice. We find that the adsorption transition temperature, the crossover exponent $\\phi$ and the metric exponent $\

B. Marcone; E. Orlandini; A. L. Stella

2007-09-10T23:59:59.000Z

328

Computationally-guided Design of Polymer Electrolytes  

E-Print Network [OSTI]

of Polymer Electrolytes Global Significance While progress of sustainable energy- harvesting techniques is promising, tandem advancements in energy storage are required to maintain a stable energy supply be a valuable contribution to the emerging sustainable energy landscape. This project applies polymer physics

329

Multicolored Electrochromism in Polymers: Structures and Devices  

E-Print Network [OSTI]

Multicolored Electrochromism in Polymers: Structures and Devices Avni A. Argun, Pierre-Henri Aubert May 12, 2004 A review of electrochromic (EC) polymers and their applications in absorption/transmission, reflective, and patterned electrochromic devices (ECDs) is presented. Fundamental properties of EC materials

Tanner, David B.

330

Cholesteric Pitch of Lyotropic Polymer Liquid Crystals  

Science Journals Connector (OSTI)

Cholesteric Pitch of Lyotropic Polymer Liquid Crystals ... The cholesteric pitch P of semiflexible helical polymer solutions was formulated using a threaded equivalent freely jointed chain model. ... The structure of cholesteric liquid crystals is characterized by the cholesteric pitch P or the cholesteric wavenumber qc (?2?/P). ...

Takahiro Sato; Jun Nakamura; Akio Teramoto; Mark M. Green

1998-02-03T23:59:59.000Z

331

Fuel cell electrolyte membrane with basic polymer  

DOE Patents [OSTI]

The present invention is an electrolyte membrane comprising an acid and a basic polymer, where the acid is a low-volatile acid that is fluorinated and is either oligomeric or non-polymeric, and where the basic polymer is protonated by the acid and is stable to hydrolysis.

Larson, James M.; Pham, Phat T.; Frey, Matthew H.; Hamrock, Steven J.; Haugen, Gregory M.; Lamanna, William M.

2012-12-04T23:59:59.000Z

332

Polymer surface treatment with particle beams  

DOE Patents [OSTI]

A polymer surface and near surface treatment process produced by irradiation with high energy particle beams. The process is preferably implemented with pulsed ion beams. The process alters the chemical and mechanical properties of the polymer surface in a manner useful for a wide range of commercial applications.

Stinnett, Regan W. (1033 Tramway La. NE., Albuquerque, NM 87122); VanDevender, J. Pace (7604 Lamplighter NE., Albuquerque, NM 87109)

1999-01-01T23:59:59.000Z

333

Polymer surface treatment with particle beams  

DOE Patents [OSTI]

A polymer surface and near surface treatment process produced by irradiation with high energy particle beams is disclosed. The process is preferably implemented with pulsed ion beams. The process alters the chemical and mechanical properties of the polymer surface in a manner useful for a wide range of commercial applications. 16 figs.

Stinnett, R.W.; VanDevender, J.P.

1999-05-04T23:59:59.000Z

334

Shape memory polymer actuator and catheter  

DOE Patents [OSTI]

An actuator system is provided for acting upon a material in a vessel. The system includes an optical fiber and a shape memory polymer material operatively connected to the optical fiber. The shape memory polymer material is adapted to move from a first shape for moving through said vessel to a second shape where it can act upon said material.

Maitland, Duncan J. (Pleasant Hill, CA); Lee, Abraham P. (Walnut Creek, CA); Schumann, Daniel L. (Concord, CA); Matthews, Dennis L. (Moss Beach, CA); Decker, Derek E. (Byron, CA); Jungreis, Charles A. (Pittsburgh, PA)

2007-11-06T23:59:59.000Z

335

The nonlinear optical, magnetic, and Mössbauer spectral properties of some iron(III) doped silica xerogels  

Science Journals Connector (OSTI)

Iron(III) species dispersed in silica have been ... synthesized with a sol-gel process. The iron(III) was introduced as the acetylacetonate complex into a solution of tetraethoxysilane to...Z-scan experimental st...

L. Rebbouh; V. Rosso; Y. Renotte; Y. Lion; F. Grandjean…

2006-05-01T23:59:59.000Z

336

Effect of gel parameters on monolithicity and density of silica aerogels  

Science Journals Connector (OSTI)

As part of continuing investigation of the preparation and characterization of silica aerogels, detailed experimental results on monolithicity and density of the aerogels as a function of catalysts and their c...

A. Venkateswara Rao; N. N. Parvathy

1993-06-01T23:59:59.000Z

337

Synthesis and characterization of transparent silica-based aerogels using methyltrimethoxysilane precursor  

Science Journals Connector (OSTI)

Silica-based aerogels with high transparency and high bending strength were prepared using methyltrimethoxysilane and non-ionic surfactant under supercritical drying condition of CO2. Non-ionic surfactant, ethyle...

Masayuki Nogami; Shohei Hotta…

2010-11-01T23:59:59.000Z

338

E-Print Network 3.0 - aperture fused silica Sample Search Results  

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

using a Kaufman type ion source to figure 8 cm diameter fused silica and silicon carbide samples... cases are shown in Table 1 and Figure 1. Using a 3 cm diameter Ion Tech...

339

E-Print Network 3.0 - ash-silica fume pastes Sample Search Results  

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

; Engineering 100 By-Products Utilization Summary: of Recycled Aggregates in Self-Compacting4 Concrete", Fly Ash, Silica Fume, Slag and Natural Pozzolans... (0.00028 in.). For...

340

Ammoniated silica-alumina gel and catalyst containing the same and processes for producing same  

SciTech Connect (OSTI)

This invention relates to hydrothermally treated silica-alumina cogels resulting in a reduction in the NH/sub 4/ content of the gel and the employment of such gels as cracking catalysts.

Alafandi, H.; Stamires, D.

1980-12-09T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Atmospheric Pressure Plasma Treatment of Fused Silica, Related Surface and Near-Surface Effects and Applications  

Science Journals Connector (OSTI)

We report on an atmospheric pressure plasma (APP) treatment of fused silica and its related surface and near-surface effects. Such treatment was performed in order to improve laser ... process gas was used. By th...

Christoph Gerhard; Tobias Weihs; Daniel Tasche…

2013-10-01T23:59:59.000Z

342

Effects from Alkali-Silica Reacton and Delayed Ettringite Formation on Reinforced Concrete Column Lap Splices  

E-Print Network [OSTI]

Reinforced concrete bridge columns can deteriorate prematurely due to the alkali-silica reaction (ASR) and/or delayed ettringite formation (DEF), causing internal expansion and cracking on the surface of the concrete. The performance...

Eck, Mary

2012-07-16T23:59:59.000Z

343

Silica-nanoparticle-dispersed methacrylate photopolymers with net diffraction efficiency near 100%  

Science Journals Connector (OSTI)

We demonstrate volume holographic recording in silica-nanoparticle-dispersed methacrylate photopolymers with reduced scattering loss as low as 2%. This is made possible by use of 13-nm...

Suzuki, Naoaki; Tomita, Yasuo

2004-01-01T23:59:59.000Z

344

Method for inhibiting silica precipitation and scaling in geothermal flow systems  

DOE Patents [OSTI]

A method for inhibiting silica scaling and precipitation in geothermal flow systems by on-line injection of low concentrations of cationic nitrogen-containing compounds, particularly polymeric imines, polymeric amines, and quaternary ammonium compounds is described.

Harrar, J.E.; Lorensen, L.E.; Locke, F.E.

1980-06-13T23:59:59.000Z

345

Effects from Alkali-Silica Reacton and Delayed Ettringite Formation on Reinforced Concrete Column Lap Splices.  

E-Print Network [OSTI]

??Reinforced concrete bridge columns can deteriorate prematurely due to the alkali-silica reaction (ASR) and/or delayed ettringite formation (DEF), causing internal expansion and cracking on the… (more)

Eck, Mary

2012-01-01T23:59:59.000Z

346

E-Print Network 3.0 - alcali-silica reactions mechanisms Sample...  

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

results for: alcali-silica reactions mechanisms Page: << < 1 2 3 4 5 > >> 1 GTQ, Chemistry 212, Dr. Glaser, FS96 --1 --GTQ on Baeyer-Villiger Reaction. (20 points,...

347

Knotted globular ring polymers: how topology affects statistics and thermodynamics  

E-Print Network [OSTI]

The statistical mechanics of a long knotted collapsed polymer is determined by a free-energy with a knot-dependent subleading term, which is linked to the length of the shortest polymer that can hold such knot. The only other parameter depending on the knot kind is an amplitude such that relative probabilities of knots do not vary with the temperature $T$, in the limit of long chains. We arrive at this conclusion by simulating interacting self-avoiding rings at low $T$ on the cubic lattice, both with unrestricted topology and with setups where the globule is divided by a slip link in two loops (preserving their topology) which compete for the chain length, either in contact or separated by a wall as for translocation through a membrane pore. These findings suggest that in macromolecular environments there may be entropic forces with a purely topological origin, whence portions of polymers holding complex knots should tend to expand at the expense of significantly shrinking other topologically simpler portions.

Marco Baiesi; Enzo Orlandini; Attilio L. Stella

2014-11-28T23:59:59.000Z

348

Selective separation of europium using polymer-enhanced ultrafiltration  

SciTech Connect (OSTI)

The U.S. Department of energy (DOE) is actively pursuing new and improved separation techniques for the cleanup of past nuclear defense production sites. Research and production activites at DOE`s Hanford Site in Richland, Wash., have created large volumes of waste streams containing hazardous and toxic chemicals along with radioactive materials. Many of these wastes will require processing for segregation into high-level, transuranic, and/or low-level waste for permanent disposal. A process to selectively remove actinides, such as americium, from liquid radioactive waste was investigated for potential use at Hanford and other contaminated DOE sites. The objective of this research was to determine the effectiveness of polymer binding followed by ultrafiltration for removal of europium (Eu), a nonradioactive surrogate for trivalent actinides such as americium. A commercially available polyacrylic acid (PAA) and a Pacific Northwest Laboratory (PNL) synthesized copolymer were tested. Both polymers significantly increased Eu removal. A cation exchange mechanism was implied by examination of the Eu-to-RCO{sub 2}{sup -} functional groups that comprise the acrylic acid monomer. The weight ratios of Eu-to-polymer needed to achieve 85% rejection of Eu were 1:6 for PAA and 1:10 for the PNL copolymer. Addition of sodium to the feed solution at a concentration three orders of magnitude greater than Eu did not adversely affect rejection of Eu. 12 refs., 12 figs., 4 tabs.

Norton, M.V. [Gray & Osborne, Inc., Seattle, WA (United States); Digiano, F.A. [Univ. of North Carolina, Chapel Hill, NC (United States); Hallen, R.T. [Pacific Northwest Lab., Richland, WA (United States)

1997-03-01T23:59:59.000Z

349

Functionalized Polymers For Binding To Solutes In Aqueous Solutions  

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

Functionalized Polymers For Binding To Solutes In Aqueous Solutions Functionalized Polymers For Binding To Solutes In Aqueous Solutions Functionalized Polymers For Binding To Solutes In Aqueous Solutions A functionalized polymer for binding a dissolved molecule in an aqueous solution is presented. Available for thumbnail of Feynman Center (505) 665-9090 Email Functionalized Polymers For Binding To Solutes In Aqueous Solutions A functionalized polymer for binding a dissolved molecule in an aqueous solution is presented. The polymer has a backbone polymer to which one or more functional groups are covalently linked. The backbone polymer can be such polymers as polyethylenimine, polyvinylamine, polyallylamine, and polypropylamine. These polymers are generally water-soluble, but can be insoluble when cross-linked. The functional group can be for example diol

350

POLYMERS IN STRUCTURAL DESIGN APPLICATIONS  

E-Print Network [OSTI]

FEP resin applications include wire and cable insulation for computer and electronic systems, telephone and alarm systems, and business-machine interconnects, FEP resin is also supplied as extruded sheet and film for release surfaces, roll covers, linings for chemical-processing tanks, and piping. A concentrate is available for Freon-blown-foam wire coating. PFA resins are used for hightemperature wire and cable insulation, heat-shrinkable tubing and roll covers, chemical-resistant linings for process-equipment components, and in semiconductor processing equipment. Materials do not adhere readily to the slippery surface of FEP, PFA, and PTFE parts. Surfaces can be chemically etched, however, to permit bonding with adhesives. Thus, low-friction surfaces of fluorocarbon tape or film can be bonded to steel, aluminum, rubber, or other materials. FEP and PFA parts can be heat sealed to themselves, to PTFE parts, or to metals at low pressure and temperatures above 310 °C. CTFE: Sensitivity to processing conditions is greater in CTFE resins than in most polymers.Molding and extruding operations require accurate temperature control, flow channel streamlining, and high pressure because of the high melt viscosity of these materials. With too little heat, the plastic is unworkable; too much heat degrades the polymer. Degradation begins at about 274 °C. Because of

Nedžad Rep?i?

351

Silica and acid-detergent fiber content of five varieties of bermudagrass  

E-Print Network [OSTI]

SILICA &ID ACID-DETERGENT FIBER CONTENT OF FIVE VARIETIES OF BERMUDAGRASS A Thesis by FREDERICK MICHAEL JUNGMAN Submitted to the Graduate College of Texas A&M Uniuersity in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE August 1971 Major Subject: Agronomy SILICA AND ACID-DETERGENT FIBER CONTENT 01' FIVE VARIETIES OF BEI~DAGRASS A Thesis by FREDERICK MICHAEL OUNGMAN Approved as to style and content by: (Chai rman of Coamd t tee) (llead of. Department...

Jungman, Frederick Michael

1971-01-01T23:59:59.000Z

352

Modifications in the correlation function in poly(vinyl alcohol)/silica hybrid wet gels  

Science Journals Connector (OSTI)

Small-angle X-ray scattering was used to study modifications in the correlation function in tetraethoxysilane-derived poly(vinyl alcohol)/silica hybrids. An additional scattering at low q was found to overlap the fundamental mass-fractal scattering from the basic silica. The fraction of both contributions to the total correlation function was estimated; this is the first time that such a study has been carried out for mass-fractal structures.

Vollet, D.R.

2008-11-28T23:59:59.000Z

353

The effect of lattice temperature on surface damage in fused silica optics  

SciTech Connect (OSTI)

We examine the effect of lattice temperature on the probability of surface damage initiation for 355nm, 7ns laser pulses for surface temperatures below the melting point to temperatures well above the melting point of fused silica. At sufficiently high surface temperatures, damage thresholds are dramatically reduced. Our results indicate a temperature activated absorption and support the idea of a lattice temperature threshold of surface damage. From these measurements, we estimate the temperature dependent absorption coefficient for intrinsic silica.

Bude, J; Guss, G; Matthews, M; Spaeth, M L

2007-10-31T23:59:59.000Z

354

Mineralogical characteristics of the silica polymorphs in relation to their biological activities  

SciTech Connect (OSTI)

Numerous aspects of minerals (including the silica polymorphs) can effect their biological activities. These include periodic structures, compositional variations, dissolution characteristics, surface properties, and particle size/shape. In order to understand mineral-induced pathogenesis in a mechanistic way, the links between these properties and biochemical processes must be elucidated. This paper presents some of the basic properties of the silica polymorphs that may relate to pathogenicity and mineralogical strategies for designing biological assays to evaluate these properties.

Guthrie, G.D. Jr. [Los Alamos National Lab., NM (United States); Heaney, P.J. [Princeton Univ., NJ (United States). Dept. of Geological and Geophysical Sciences

1993-10-01T23:59:59.000Z

355

CX-010528: Categorical Exclusion Determination | Department of Energy  

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

528: Categorical Exclusion Determination 528: Categorical Exclusion Determination CX-010528: Categorical Exclusion Determination Durability Investigation for Quarternary Phosphonium-based Polymer Hydroxide Exchange Membranes CX(s) Applied: B3.6 Date: 09/18/2012 Location(s): Delaware Offices(s): Advanced Research Projects Agency-Energy Funding will support two efforts: 1) durability testing and analysis of battery cells outfitted with the University of Delaware's novel phosphonium based polymer hydroxide exchange membrane, and 2) creation of a batch of phosphonium based polymer hydroxide exchange membranes for use in another ARPA-E project. CX-010528.pdf More Documents & Publications CX-000598: Categorical Exclusion Determination CX-009898: Categorical Exclusion Determination Energy Storage Systems 2012 Peer Review Presentations - Poster Session 1

356

Infrared study on the adsorption of CO and NO on silica-supported Pd and Pt-Pd  

SciTech Connect (OSTI)

The IR spectra of NO adsorbed on silica-supported palladium had bands at 1735 and 1645/cm, which were assigned to linearly bound NO and to NO linearly bound to low-coordinated palladium, respectively. Bands at 1980 and 2070/cm in the spectrum of CO adsorbed on palladium were assigned multiply coordinated and linear CO, respectively. Carbon monoxide was completely displaced from palladium by nitric oxide, preadsorbed nitric oxide was partly displaced from palladium by carbon monoxide, and carbon dioxide and nitrous oxide were formed in both processes. A band at 2180/cm provided evidence for adsorbed isocyanate species. All bands shifted to higher frequencies by approx. 10/cm for 1:1 palladium/platinum bimetallic clusters; the carbon monoxide was readily removed by evacuating at room temperature, a fact that my be used in catalyst surface area determinations.

Grill, C.M.; Gonzalez, R.D.

1980-04-17T23:59:59.000Z

357

Syntheses and studies of acetylenic polymers  

SciTech Connect (OSTI)

Based on new diiodo aryl compounds a series of novel soluble polymers, poly(2,5-dialkoxy-1,4-phenyleneethynylene)s (PPE polymers) were synthesized using palladium-catalysis. The molecular weights (MW) range from 8,000 to 40,000. Properties such as absorption, fluorescence, and conductivity were studied. A PPE polymer with butoxy side chain exhibits a weak electrical conductivity ({sigma} = 10{sup {minus}3} S/cm) after doping with AsF{sub 5}. Absorption spectra in THF solution at room temperature (RT) show a maximum at 440 nm. However, absorption spectra of PPE polymers in the film state at (RT) show a maximum at 480 nm. PPE polymer-based light emitting diode (LED) devices have been prepared; greenish light from these LED devices can be observed. Poly(ethynylene-p-arylene-ethynylene-silylene)s were synthesized through the same palladium-catalyzed polymerization; MWs are between 6,000 and 82,000. Absorption and fluorescence were studied. Some of these polymers exhibit thermotropic liquid crystalline properties. In addition, nonlinear optical properties were briefly examined. Poly(silylene-ethynylene) homopolymers as well as alternating copolymers were synthesized through a novel palladium-catalyzed polymerization; MWs range from 56 {times} 10{sup 3} to 5.3 {times} 10{sup 3}. Thermal stability of these was also investigated; char yields range from 56 to 83%. One of these polymers exhibits thermotropic liquid crystalline properties.

Yiwei, Ding

1994-03-03T23:59:59.000Z

358

A Boron Subphthalocyanine Polymer: Poly(4-methylstyrene)-co-poly(phenoxy boron subphthalocyanine)  

Science Journals Connector (OSTI)

A Boron Subphthalocyanine Polymer: Poly(4-methylstyrene)-co-poly(phenoxy boron subphthalocyanine) ... Deuterated chloroform with 0.05% (v/v) tetramethylsilane (TMS) was purchased from Cambridge Isotope Laboratories (St. ... Before additional effort was put into obtaining a BsubPc vinyl monomer we first wanted to determine whether or not the BsubPc group is a radical scavenger. ...

Jeremy D. Dang; Jessica D. Virdo; Benoît H. Lessard; Elijah Bultz; Andrew S. Paton; Timothy P. Bender

2012-09-28T23:59:59.000Z

359

Orientational ordering of short LC rods in an anisotropic liquid crystalline polymer glass  

E-Print Network [OSTI]

Orientational ordering of short LC rods in an anisotropic liquid crystalline polymer glass Lorin the glass transition is determined by field theory. Microscopic anisotropic interactions can align the LC the glass transition. Host anisotropic glass formers made of mesogens with side chains were studied recently

Cao, Jianshu

360

Open Questions about Polymer Friction JANET S. WONG,1  

E-Print Network [OSTI]

perfluoropolyethers are more effective than competing polymers. In the regulation of the viscosity of engine oils

Granick, Steve

Note: This page contains sample records for the topic "determination silica polymer" 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

Conductive inks for metalization in integrated polymer microsystems  

DOE Patents [OSTI]

A system of metalization in an integrated polymer microsystem. A flexible polymer substrate is provided and conductive ink is applied to the substrate. In one embodiment the flexible polymer substrate is silicone. In another embodiment the flexible polymer substrate comprises poly(dimethylsiloxane).

Davidson, James Courtney (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA); Maghribi, Mariam N. (Livermore, CA); Benett, William J. (Livermore, CA); Hamilton, Julie K. (Tracy, CA); Tovar, Armando R. (San Antonio, TX)

2006-02-28T23:59:59.000Z

362

Glass/polymer composites and methods of making  

DOE Patents [OSTI]

The present invention relates to new glass/polymer composites and methods for making them. More specifically, the invention is glass/polymer composites having phases that are at the molecular level and thereby practicably indistinguishable. The invention further discloses making molecular phase glass/polymer composites by mixing a glass and a polymer in a compatible solvent.

Samuels, W. D. (Richland, WA); Exarhos, Gregory J. (Richland, WA)

1995-01-01T23:59:59.000Z

363

Assistant template and co-template agents in modeling mesoporous silicas and post-synthesizing organofunctionalizations  

SciTech Connect (OSTI)

Mesoporous SBA-16 silicas were synthesized through a direct methodology using the template (F127) combined with co-templates (ethanol and n-butanol), with tetraethylorthosilicate as the silica source. These ordered mesoporous silica were characterized by elemental analyses, infrared spectroscopy, solid-state nuclear magnetic resonance for {sup 13}C (CP/MAS) and {sup 29}Si (HP/DEC) nuclei, nitrogen sorption/desorption processes, small angle X-ray analyses (SAXS) and transmission electron microscopy (TEM). SAXS and TEM results confirmed the space group Im3m and cubic 3D symmetry, typical for highly ordered SBA-16. The sorption/desorption data for SBA-16 and when functionalized gave type IV isotherms, with hysteresis loop H2. Surface areas of 836; 657 and 618 m{sup 2} g{sup -1} and average pore diameters of 7.99; 8.10 and 9.85 nm, for SBA-16A, SBA-16B and SBA-16C were obtained, respectively. When functionalized the silicas presented a reduction in surface area, pore volume and pore diameter due to the pendant chains that interfere with nitrogen sorption in these measurements. The co-template ethanol favors the ordered mesopores with highest wall thicknesses. - Graphical Abstract: The mesoporous SBA-16 can be synthesized from binary (F127/TEOS) or ternary (F127/alcohol/TEOs) systems to give well-ordered mesoporous silicas. The co-templates ethanol or butanol gave the final material with highest wall thickness, mainly with ethanol. After these syntheses the pores were successfully organofunctionalized to give a good incorporation of the silylating agents. The final silicas presented of well-arranged solid characteristics as expressing by three distinct peaks, as indexed by the corresponding planes. Highlights: Black-Right-Pointing-Pointer Syntheses of mesoporous silicas by using ternary (F127/agent/TEOS) and binary (F127/TEOS) systems. Black-Right-Pointing-Pointer Use of co-templates to synthesize mesoporous silicas with larger wall thicknesses. Black-Right-Pointing-Pointer Immobilization of pendant chains inside the porous silicas. Black-Right-Pointing-Pointer Ordered mesoposous silicas as new materials for possible applications on sorption and delivering drug systems.

Oliveira, Vaeudo V. [Institute of Chemistry, University of Campinas, UNICAMP, PO Box 6154, 13084-971 Campinas, SP (Brazil)] [Institute of Chemistry, University of Campinas, UNICAMP, PO Box 6154, 13084-971 Campinas, SP (Brazil); Airoldi, Claudio, E-mail: airoldi@iqm.unicamp.br [Institute of Chemistry, University of Campinas, UNICAMP, PO Box 6154, 13084-971 Campinas, SP (Brazil)] [Institute of Chemistry, University of Campinas, UNICAMP, PO Box 6154, 13084-971 Campinas, SP (Brazil)

2012-12-15T23:59:59.000Z

364

The viscosity of polymer melts  

Science Journals Connector (OSTI)

A simple theoretical argument is presented that gives the scaling behavior of the relaxation time in a polymer melt as a function of molecular weight M. The framework for this theory is based on the reptation model of de Gennes but also incorporates the effects of excluded volume. It is argued that the effects of excluded volume change the relaxation time from M 3 to M 3 exp(const×M 2/3). This argument agrees qualitatively with a direct simulation of the reptation model that incorporates many?chain excluded volume interactions. This simulation fits experimental data quite well giving an effective power law relationship between viscosity ? and molecular weight namely ??M 3.4±.1.

J. M. Deutsch

1986-01-01T23:59:59.000Z

365

Megahertz organic/polymer diodes  

DOE Patents [OSTI]

Featured is an organic/polymer diode having a first layer composed essentially of one of an organic semiconductor material or a polymeric semiconductor material and a second layer formed on the first layer and being electrically coupled to the first layer such that current flows through the layers in one direction when a voltage is applied in one direction. The second layer is essentially composed of a material whose characteristics and properties are such that when formed on the first layer, the diode is capable of high frequency rectifications on the order of megahertz rectifications such as for example rectifications at one of above 100KHz, 500KhZ, IMHz, or 10 MHz. In further embodiments, the layers are arranged so as to be exposed to atmosphere.

Katz, Howard Edan; Sun, Jia; Pal, Nath Bhola

2012-12-11T23:59:59.000Z

366

Image enhancement with polymer grid triode arrays  

SciTech Connect (OSTI)

An array of polymer grid triodes connected by a common grid functions as a {open_quotes}plastic retina,{close_quotes} providing local contrast gain control for image enhancement. This simple device, made from layers of conducting polymers, functions as an active resistive network that performs center-surround filtering. The polymer grid triode array with common grid is a continuous analog of the discrete approach of Mead, with a variety of fabrication advantages and significant savings in area within the unit cell of each pixel. 6 refs., 4 figs.

Heeger, A.J.; Heeger, D.J.; Langan, J. [UNIAX Corporation, Santa Barbara, CA (United States)] [and others

1995-12-08T23:59:59.000Z

367

Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties  

SciTech Connect (OSTI)

Several new types of silicon-containing preceramic polymers, i.e., poly(diorganosilacetylene) and poly(diorganosilvinylene) have been synthesized with molecular weights from 10,000 to 120,000. These polymers could be thermally converted to SiC with a moderate to high char yields. Ready solubility and good processability made these types of polymers attractive in their applications to ceramics. The thermal polymerization of diethynyldiphenyl-silane, which was reported in 1968 to afford poly(diphenylsilyldiacetylene) via dehydrogenation, was reinvestigated. Spectroscopic studies showed that the polymer had a structure of polyacetylene type not diacetylene. Diphenyldiethynylgermane and a series of diorganodiethynylsilances were synthesized. These could be polymerized in the presence of MoCl{sub 5} or WCl{sub 6} to afford a soluble, violet material with Mw as high as 108,000. 100 refs., 56 figs., 16 tabs.

Pang, Yi.

1991-10-07T23:59:59.000Z

368

The conformational evolution of elongated polymer solutions tailors the polarization of light-emission from organic nanofibers  

E-Print Network [OSTI]

Polymer fibers are currently exploited in tremendously important technologies. Their innovative properties are mainly determined by the behavior of the polymer macromolecules under the elongation induced by external mechanical or electrostatic forces, characterizing the fiber drawing process. Although enhanced physical properties were observed in polymer fibers produced under strong stretching conditions, studies of the process-induced nanoscale organization of the polymer molecules are not available, and most of fiber properties are still obtained on an empirical basis. Here we reveal the orientational properties of semiflexible polymers in electrospun nanofibers, which allow the polarization properties of active fibers to be finely controlled. Modeling and simulations of the conformational evolution of the polymer chains during electrostatic elongation of semidilute solutions demonstrate that the molecules stretch almost fully within less than 1 mm from jet start, increasing polymer axial orientation at the jet center. The nanoscale mapping of the local dichroism of individual fibers by polarized near-field optical microscopy unveils for the first time the presence of an internal spatial variation of the molecular order, namely the presence of a core with axially aligned molecules and a sheath with almost radially oriented molecules. These results allow important and specific fiber properties to be manipulated and tailored, as here demonstrated for the polarization of emitted light.

Andrea Camposeo; Israel Greenfeld; Francesco Tantussi; Maria Moffa; Francesco Fuso; Maria Allegrini; Eyal Zussman; Dario Pisignano

2014-07-30T23:59:59.000Z

369

High Resolution Additive Patterning of Nanoparticles and Polymers Enabled by Vapor Permeable Polymer Templates.  

E-Print Network [OSTI]

??The structure and chemistry of nanoparticles and polymers are interesting for applications in electronics and sensors. However, because they are outside of the standard material… (more)

Demko, Michael Thomas

2012-01-01T23:59:59.000Z

370

Polymer/Elastomer and Composite Material Science  

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

/ Elastomer and / Elastomer and Composite Material Science KEVIN L. SIMMONS Pacific Northwest National Laboratory, Richland, WA DOE Headquarters, Forrestal Bldg. October 17-18, 2012 January 17, 2013 Kevin.simmons@pnnl.gov 1 Outline Hydrogen production, transmission, distribution, delivery system Common themes in the hydrogen system Automotive vs infrastructure Hydrogen use conditions Polymer/elastomer and composites compatibility? Common materials in BOP components, hoses, and liners Common materials in composite tank and piping Material issues Polymers/Elastomers Composites Questions 2 Main Points to Remember 1) Polymers are extensively used in hydrogen and fuel cell applications 2) Hydrogen impact on polymers is not well understood 3) Next steps 3 4 Hydrogen Production Systems

371

Neutron scattering from adsorbed polymer layers  

Science Journals Connector (OSTI)

Neutron scattering from adsorbed polymer layers ... Small-Angle Neutron Scattering Study of Cyclic Poly(ethylene glycol) Adsorption on Colloidal Particles ... Small-Angle Neutron Scattering Study of Cyclic Poly(ethylene glycol) Adsorption on Colloidal Particles ...

Terence Cosgrove; Timothy G. Heath; Keith Ryan; Trevor L. Crowley

1987-11-01T23:59:59.000Z

372

Polymer/Elastomer and Composite Material Science  

Broader source: Energy.gov [DOE]

Presentation by Kevin Simmons, Pacific Northwest National Laboratory, at the U.S. Department of Energy's Polymer and Composite Materials Meeting, held October 17-18, 2012, in Washington, D.C.

373

Chemical vapor deposition of functionalized isobenzofuran polymers  

E-Print Network [OSTI]

This thesis develops a platform for deposition of polymer thin films that can be further tailored by chemical surface modification. First, we explore chemical vapor deposition of functionalized isobenzofuran films using ...

Olsson, Ylva Kristina

2007-01-01T23:59:59.000Z

374

Electrical conductivity of segregated network polymer nanocomposites  

E-Print Network [OSTI]

in both electrical and mechanical properties with low carbon black loading, while the solution-based composite achieves its maximum enhancement at higher carbon black loading (~25wt%). The effect of the particle size ratio between the polymer particle...

Kim, Yeon Seok

2009-06-02T23:59:59.000Z

375

Catalyst supports for polymer electrolyte fuel cells  

Science Journals Connector (OSTI)

...Bruce, Richard Catlow and Peter Edwards Catalyst supports for polymer electrolyte fuel...durability in fuel cells is to discover catalyst supports that do not corrode, or corrode...black support. fuel cells|oxides|catalyst supports|nanoparticles|conductivity...

2010-01-01T23:59:59.000Z

376

Polymer-based electrocaloric cooling devices  

DOE Patents [OSTI]

Cooling devices (i.e., refrigerators or heat pumps) based on polymers which exhibit a temperature change upon application or removal of an electrical field or voltage, (e.g., fluoropolymers or crosslinked fluoropolymers that exhibit electrocaloric effect).

Zhang, Qiming; Lu, Sheng-Guo; Li, Xinyu; Gorny, Lee; Cheng, Jiping; Neese, Bret P; Chu, Baojin

2014-10-28T23:59:59.000Z

377

Numerical Simulation of Surfactant-Polymer Flooding  

Science Journals Connector (OSTI)

We propose a mathematical model (numerical simulation) of surfactant-polymer flooding for a three-phase six-component system. ... model takes into account various phenomena inherent to flooding, the effect of sur...

Baoguang Jin; Hanqiao Jiang; Xiansong Zhang…

2014-03-01T23:59:59.000Z

378

Synthesis and characterization of conducting polymer actuators  

E-Print Network [OSTI]

Conducting polymers are known to mechanically respond to electrochemical stimuli and have been utilized as linear actuators. To date, the most successful mechanism for actuation is ionic ingress and egress, though mechanisms ...

Vandesteeg, Nathan A. (Nathan Alan)

2007-01-01T23:59:59.000Z

379

Large displacement fast conducting polymer actuators  

E-Print Network [OSTI]

Conducting polymers are a promising class of electroactive materials that undergo volumetric changes under applied potentials, which make them particularly useful for many actuation applications. Polypyrrole , is one of ...

Chen, Angela Y. (Angela Ying-Ju), 1982-

2006-01-01T23:59:59.000Z

380

Carbon nanotube polymer composition and devices  

DOE Patents [OSTI]

A thin film device and compound having an anode, a cathode, and at least one light emitting layer between the anode and cathode, the at least one light emitting layer having at least one carbon nanotube and a conductive polymer.

Liu, Gao (Oakland, CA); Johnson, Stephen (Richmond, CA); Kerr, John B. (Oakland, CA); Minor, Andrew M. (El Cerrito, CA); Mao, Samuel S. (Castro Valley, CA)

2011-06-14T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Counting primary loops in polymer gels  

E-Print Network [OSTI]

Much of our fundamental knowledge related to polymer networks is built on an assumption of ideal end-linked network structure. Real networks invariably possess topological imperfections that negatively affect mechanical ...

Zhou, Huaxing

382

Electronic Structure Calculations on Helical Conducting Polymers  

Science Journals Connector (OSTI)

Electronic Structure Calculations on Helical Conducting Polymers ... Therefore, we select the B3LYP/6-31G* methodology to calculate the oligomers. ... Table 3 shows several calculated parameters. ...

Juan D. Ripoll; Andrei Serna; Doris Guerra; Albeiro Restrepo

2010-09-28T23:59:59.000Z

383

Application of Conducting Polymers in Chemical Analysis  

Science Journals Connector (OSTI)

This paper presents recent achievements in the field of analytical application of conducting polymers, most of which were published in the last five years. Based on 171 references mainly to original papers in...

Marek Trojanowicz

2003-12-01T23:59:59.000Z

384

Poisson Bracket Formulation of Nematic Polymer Dynamics  

E-Print Network [OSTI]

We formulate the dynamical theory of nematic polymers, starting from a microscopic Poisson bracket approach. We find that the Poisson bracket between the nematic director and momentum depends on the (Maier-Saupe) order parameter of the nematic phase. We use this to derive reactive couplings of the nematic director to the strain rates. Additionally, we find that local dynamics breaks down as the polymers begin to overlap. We offer a physical picture for both results.

Randall D. Kamien

1999-06-22T23:59:59.000Z

385

Monte Carlo study of living polymers with the bond-fluctuation method  

Science Journals Connector (OSTI)

The highly efficient bond-fluctuation method for Monte Carlo simulations of both static and dynamic properties of polymers is applied to a system of living polymers. Parallel to stochastic movements of monomers, which result in Rouse dynamics of the macromolecules, the polymer chains break, or associate at chain ends with other chains and single monomers, in the process of equilibrium polymerization. We study the changes in equilibrium properties, such as molecular-weight distribution, average chain length, and radius of gyration, and specific heat with varying density and temperature of the system. The results of our numeric experiments indicate a very good agreement with the recently suggested description in terms of the mean-field approximation. The coincidence of the specific heat maximum position at kBT=V/4 in both theory and simulation suggests the use of calorimetric measurements for the determination of the scission-recombination energy V in real experiments.

Yannick Rouault and Andrey Milchev

1995-06-01T23:59:59.000Z

386

Selective sorption of PCBs by low-cost polymers and application to soil washing processes  

SciTech Connect (OSTI)

Surfactant-assisted soil washing and soil flushing processes have shown to be a promising soil decontamination method. In these and other remediation technologies that employ surfactants to mobilize organic contaminants, large volumes of contaminated aqueous solutions are generated. An efficient process to selectively concentrate the organic contaminant from the aqueous surfactant solution, thereby allowing the recycle of the surfactant, is considered essential for cost-effective application of these remediation methods. To this end, a process was developed wherein commercial, low-cost polymers are used to selectively sorb PCBs and petroleum oils from aqueous surfactant solutions. Sorption isotherms and sorption rates were determined for a large number of polymer sorbents and several significant structure-property relationships were observed. Two classes of polymers, polyester elastomers and carbon-filled elastomer rubbers (e.g., recycled rubber tire), were found to perform superiorly in this application and a successful pilot-scale demonstration of the process was conducted.

Sivavec, T.M.; Webb, J.L.; Gascoyne, D.G. [GE Corporate Research and Development, Schenectady, NY (United States)

1996-10-01T23:59:59.000Z

387

Multidimensional Random Polymers : A Renewal Approach  

E-Print Network [OSTI]

In these lecture notes, which are based on the mini-course given at 2013 Prague School on Mathematical Statistical Physics, we discuss ballistic phase of quenched and annealed stretched polymers in random environment on ${\\mathbb Z}^d$ with an emphasis on the natural renormalized renewal structures which appear in such models. In the ballistic regime an irreducible decomposition of typical polymers leads to an effectiverandom walk reinterpretation of the latter. In the annealed casethe Ornstein-Zernike theory based on this approach paves the way to an essentially complete control on the level of local limit results and invariance principles. In the quenched case, the renewal structure maps the model of stretched polymers into an effective model of directed polymers. As a result one is able to use techniques and ideas developed in the context of directed polymers in order to address issues like strong disorder in low dimensions and weak disorder in higher dimensions. Among the topics addressed: Thermodynamics of quenched and annealed models, multi-dimensional renewal theory (under Cramer's condition), renormalization and effective random walk structure of annealed polymers, very weak disorder in dimensions $d\\geq 4$ and strong disorder in dimensions $d=1,2$.

Dmitry Ioffe

2014-11-30T23:59:59.000Z

388

Effect of silica on the properties of cellulose acetate/polyethylene glycol membranes for reverse osmosis  

Science Journals Connector (OSTI)

Abstract In this work, a series of cellulose acetate/polyethylene glycol-600 membranes, with varying ratios were prepared by 2-stage phase inversion protocol. The permeation properties were studied by subjecting membranes in indigenously fabricated reverse osmosis plant. After optimization of different CA/PEG ratios, the membrane with highest salt rejection capacity was selected and modified with varying amount of silica. The Modified membranes were characterized for their permeation properties, hydrophilicity, compositional analysis, thermal stability, mechanical strength and morphological studies. Silica significantly influenced the permeation performance of composite membrane. The flux enhanced from 0.35 to 2.46 L/h m2 along with an 11.41% relative increase in salt rejection. The hydrophilicity was significantly enhanced by the addition of silica. In FTIR spectra, the broadening of the peak around 3500 cm? 1 and emergence of peak at 950 cm? 1 specified the incorporation of silica particles. The thermal analysis indicated the relative increase in degradation temperature (Tmax) and glass transition temperature (Tg) for CPS-5 membrane. The mechanical stability of the modified membranes, increased initially, but declined with further addition of silica. The results indicated that the incorporation of SiO2 content in the casting solution improved the fouling resistance of the membranes.

Adnan Ahmad; Sidra Waheed; Shahzad Maqsood Khan; Sabad e-Gul; Muhammad Shafiq; Muhammad Farooq; Khairuddin Sanaullah; Tahir Jamil

2015-01-01T23:59:59.000Z

389

H2O absorption spectroscopy for determination of temperature and H2O mole fraction in  

E-Print Network [OSTI]

for in situ determination of temperature and H2O mole fraction in silica SiO2 particle-forming flames. Frequency modulation of near-infrared emission from a semiconductor diode laser was used to obtain multiple-phase combustion synthesis of particles is an industrially significant synthesis method for the pro- duction

Wooldridge, Margaret S.

390

Intraparticle heat and mass transfer characteristics of silica-gel/water vapor adsorption  

SciTech Connect (OSTI)

Recently, highly efficient energy utilization systems which extensively employ adsorption phenomena such as pressure swing adsorption, heat storage, adsorption heat pump, etc. are being regarded as one of the countermeasures for environmental issues such as green house effect and ozone layer destruction. An Adsorption Heat Pump (AHP) has been investigated as one of the important techniques via which cold heat energy is obtained from waste thermal energy below 373K without using electricity and CFCs. An AHP normally consists of an adsorber and an evaporator/condenser and cold heat energy is generated by latent heat of evaporation during adsorption process. For realizing the AHP technology, it has been pointed out that the development of an adsorber with optimum heat and mass transfer characteristics is essentially important. In this study, experimental studies were carried out which was based on the data of temperature inside the adsorbent particle and adsorptivity profiles at the adsorption/desorption process by volumetric method. To clarify adsorption mechanism relatively large silica-gel particle (7 mm f) was used. Temperature distribution in the particle is determined at the center, at one half radius in the radial direction and at the surface by using very thin (30 mm f) thermocouples. The temperatures at these points simultaneously increase/decrease as soon as the adsorption/desorption started, reached their respective maximum/minimum values and then return to initial temperature. The temperature profiles for the adsorption process show that the temperature at the surface is initially slightly higher than the other two points. All three points reached their respective maximum temperature at the same time with the temperature at the center point the highest and at the surface the lowest. The temperature profiles during the desorptive process are almost exactly the opposite to that of the adsorption process. This shows that the adsorption phenomena can take place not only at the surface but inside the adsorbent particle, implying that intraparticle vapor diffusion has a great influence on adsorptivity.

Yamamoto, Eri; Watanabe, Fujio; Hasatani, Masanobu

1999-07-01T23:59:59.000Z

391

E-Print Network 3.0 - alkali-silica reaction gel Sample Search...  

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

for polymer- ization reactions. Preparation of 3,3'-Azobis(6-Amino- 1,2,4,5-Tetrazine) Michael A. Hiskey David Source: Los Alamos National Laboratory, Theoretical...

392

Polymer micromold and fabrication process  

DOE Patents [OSTI]

A mold assembly is disclosed with micro-sized features in which the hollow portion thereof is fabricated from a sacrificial mandrel which is surface treated and then coated to form an outer shell. The sacrificial mandrel is then selectively etched away leaving the outer shell as the final product. The sacrificial mandrel is fabricated by a precision lathe, for example, so that when removed by etching the inner or hollow area has diameters as small as 10`s of micros ({micro}m). Varying the inside diameter contours of the mold can be accomplished with specified ramping slopes formed on the outer surface of the sacrificial mandrel, with the inside or hollow section being, for example, 275 {micro}m in length up to 150 {micro}m in diameter within a 6 mm outside diameter (o.d.) mold assembly. The mold assembly itself can serve as a micronozzle or microneedle, and plastic parts, such as microballoons for angioplasty, polymer microparts, and microactuators, etc., may be formed within the mold assembly. 6 figs.

Lee, A.P.; Northrup, M.A.; Ahre, P.E.; Dupuy, P.C.

1997-08-19T23:59:59.000Z

393

Interfacial thermal conductance in spun-cast polymer films and polymer brushes  

E-Print Network [OSTI]

represents the length of a material of thermal conduc- tivity providing an equivalent thermal resistance inorganic materials and anharmonic polymers have potentially intriguing thermal transport behavior. The low. This requirement proves challenging for low thermal conductivity materials like amorphous polymers. The effective

Braun, Paul

394

Friction in (im-)miscible polymer brush systems and the role of transverse polymer-tilting  

E-Print Network [OSTI]

Friction in (im-)miscible polymer brush systems and the role of transverse polymer-tilting Sissi de preferred solvent, leading to low friction and low wear rates. Here, we demonstrate, using molecular systems also show smaller friction than miscible systems, although the friction reduction is less than

Mueser, Martin

395

Alkali-silica reaction products: Comparison between samples from concrete structures and laboratory test specimens  

SciTech Connect (OSTI)

Alkali-silica gels (ASG) were investigated in concrete from bridge structures (constructed from the 1920s to 2000), as well as in experimental specimens; employing optical microscopy, petrographic image analysis, and scanning electron microscopy combined with energy dispersive spectroscopy (SEM/EDS). The main differences were found in the chemical composition and morphology of the ASGs. ASGs which had formed in older concrete samples (50-80 years old) show a partly crystalline structure and higher Ca{sup 2+} content, indicating their aging and maturation. Younger concrete samples and experimental test specimens exhibit the presence of amorphous ASG. The chemistry of ASG from experimental specimens reflects the chemical composition of accelerating solutions. - Research Highlights: {yields} Quantitative analysis of alkali-silica gels {yields} Comparison of ASR in experimental conditions with ASR in bridge structures {yields} Investigation of factors affecting alkali-silica reaction {yields} Investigation of ASR of different types of aggregates.

Sachlova, Sarka, E-mail: lukschova@seznam.cz; Prikryl, Richard; Pertold, Zdenek

2010-12-15T23:59:59.000Z

396

CALE EOS form 2 fits for high pressure fused silica Hugoniot data  

SciTech Connect (OSTI)

The Hugoniot data on fused silica that are displayed on page 321 of the well-known volume ''LASL Shock Hugoniot Data, Stanley P. Marsh, Editor'' are fit to the EOS form 2 such as is used in CALE and other hydrocodes. Two fits are given: one to represent that data set over its full range (up to 84 GPa (840 kbar)) as well as a better fit for the pressure range below about 33 GPa (330 kbar). These EOSs have the strong point of being relatively simple for the user to implement and should be used to roughly represent the beyond-elastic response of fused silica in hydrocode simulations. They will not correctly reproduce the complex multiple-wave ramp-shock structure known to exist in fused silica at lower pressures.

Hare, D E; Managan, R A

2005-11-17T23:59:59.000Z

397

Preparation and sintering of silica-doped zirconia by colloidal processing  

SciTech Connect (OSTI)

Silica-doped (SiO{sub 2} = 0--1.0 mass%) zirconia (3 mol% Y{sub 2}O{sub 3}-doped tetragonal ZrO{sub 2}) compacts are prepared from hetero-coagulated and well-dispersed suspensions by colloidal processing. The suspensions are consolidated by a pressure filtration technique. The green density of the compacts consolidated from the well-dispersed suspensions is higher than that from the hetero-coagulated suspensions. The lower density of the latter compacts is improved by a subsequent cold isostatic pressing (CIP) at 400 MPa. The sinterability of the compacts at 1,200 C is greatly affected by the amount of doped silica. The densification and grain growth are hindered by silica doping above 0.3 wt% at 1,200 C. All the compacts are densificated to a relative density of above 99% by sintering at 1,300 C for 2 h.

Uchikoshi, T.; Sakka, Y.; Ozawa, K.; Hiraga, K. [National Research Inst. for Metals, Tsukuba, Ibaraki (Japan)

1997-09-01T23:59:59.000Z

398

SANS study of interaction of silica nanoparticles with BSA protein and their resultant structure  

SciTech Connect (OSTI)

Small angle neutron scattering (SANS) has been carried out to study the interaction of anionic silica nanoparticles (88 Å) with globular protein Bovine Serum Albumin (BSA) (M.W. 66.4 kD) in aqueous solution. The measurements have been carried out on fixed concentration (1 wt %) of Ludox silica nanoparticles with varying concentration of BSA (0–5 wt %) at pH7. Results show that silica nanoparticles and BSA coexist as individual entities at low concentration of BSA where electrostatic repulsive interactions between them prevent their aggregation. However, as the concentration of BSA increases (? 0.5 wt %), it induces the attractive depletion interaction among nanoparticles leading to finally their aggregation at higher BSA concentration (2 wt %). The aggregates are found to be governed by the diffusion limited aggregation (DLA) morphology of fractal nature having fractal dimension about 2.4.

Yadav, Indresh, E-mail: vkaswal@barc.gov.in; Aswal, V. K., E-mail: vkaswal@barc.gov.in [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai-400085 (India); Kohlbrecher, J. [Laboratory for Neutron Scattering, Paul Scherrer Institute, CH-5232 PSI Villigen Switzerland (Switzerland)

2014-04-24T23:59:59.000Z

399

In situ atom transfer radical polymerization of styrene in the presence of nanoporous silica aerogel: Kinetic study and investigation of thermal properties  

Science Journals Connector (OSTI)

Atom transfer radical polymerization (ATRP) of styrene was performed at 110 °C in the presence of organically modified silica aerogel. A hydrophobic silica aerogel was prepared by a two-step, acid–base catalyz...

Seyed-Ataollah Mirshafiei-Langari; Vahid haddadi-Asl…

2013-05-01T23:59:59.000Z

400

CX-004142: Categorical Exclusion Determination | Department of Energy  

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

4142: Categorical Exclusion Determination 4142: Categorical Exclusion Determination CX-004142: Categorical Exclusion Determination Compact High Temperature Direct Current Bus Capacitors for Electric Vehicles Using High Performance Electroactive Polymers CX(s) Applied: B3.6, B5.1 Date: 09/17/2010 Location(s): State College, Pennsylvania Office(s): Energy Efficiency and Renewable Energy Strategic Polymer Sciences, Inc., proposes to develop compact film capacitors with high dielectric constant and high temperature stability using its proprietary electroactive polymer dielectric compositions. The capacitors would be able to operate at above 140 degrees Celsius with a size that is more than 60% smaller than current polypropylene (PP) direct current bus capacitors. Prototype capacitors would be developed for

Note: This page contains sample records for the topic "determination silica polymer" 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

Method of making metal-polymer composite catalysts  

DOE Patents [OSTI]

A metal-polymer-carbon composite catalyst for use as a cathode electrocatalyst in fuel cells. The catalyst includes a heteroatomic polymer; a transition metal linked to the heteroatomic polymer by one of nitrogen, sulfur, and phosphorus, and a recast ionomer dispersed throughout the heteroatomic polymer-carbon composite. The method includes forming a heteroatomic polymer-carbon composite and loading the transition metal onto the composite. The invention also provides a method of making a membrane electrode assembly for a fuel cell that includes the metal-polymer-carbon composite catalyst.

Zelena, Piotr (Los Alamos, NM); Bashyam, Rajesh (Los Alamos, NM)

2009-06-23T23:59:59.000Z

402

IMPROVING SILICA FUME FOR CONCRETE BY SURFACE TREATMENT X. Li and D.D.L. Chung1  

E-Print Network [OSTI]

(Type I) from Lafarge Corp. (Southfield, MI). The silica fume (Elkem Materials, Inc., Pittsburgh, PA, EMS 965) was used in the amount of 15% by weight of cement. Surface treatment of silica fume Printed in the USA. All rights reserved 0008-8846/98 $19.00 .00 PII S0008-8846(98)00017-9 493 #12;effect

Chung, Deborah D.L.

403

The influence of polyethyleneimine type and molecular weight on the CO2 capture performance of PEI-nano silica adsorbents  

Science Journals Connector (OSTI)

Abstract Amine–silica adsorbents are considered alternatives to aqueous solutions of amines, which have been traditionally used to capture carbon dioxide (CO2) from flue gas. Among amine–silica adsorbents, polyethyleneimine (PEI)-silica is particularly effective at capturing CO2 from flue gas due to its high thermal stability. In this study, we investigated the influence of PEI type (i.e. branched vs. linear) and molecular weight on the CO2 capture performance of PEI-silica adsorbents. PEI molecular weight influenced the thermal stability of PEI-silica adsorbents; however, when the molecular weight was ?1200 Da the increase in stability was negligible in the temperature range of 25–160 °C. Branched \\{PEIs\\} (BPEIs) achieved higher CO2 saturated sorption capacities compared to linear \\{PEIs\\} (LPEIs); however, \\{LPEIs\\} were more stable than \\{BPEIs\\} during CO2 sorption–desorption cycling. PEI molecular weight also influenced the CO2 saturated sorption capacity; CO2 saturated sorption capacity decreased as PEI molecular weight increased, and among the adsorbents tested in this study BPEI/800-silica had the highest CO2 saturated sorption capacity (202 mg CO2/g adsorbent). Both PEI type and molecular weight exhibited influence on the sorption or desorption heat of PEI-silica adsorbents. The CO2 regeneration heat was much lower than that of MEA solution for all PEI-silica adsorbents tested in this study.

Kaimin Li; Jianguo Jiang; Feng Yan; Sicong Tian; Xuejing Chen

2014-01-01T23:59:59.000Z

404

Am J Epidemiol . Author manuscript Aluminum and silica in drinking water and the risk of Alzheimers disease'  

E-Print Network [OSTI]

Am J Epidemiol . Author manuscript Page /1 10 Aluminum and silica in drinking water and the risk associations between exposure to aluminum or silica from drinking water and risk of cognitive decline, dementia of dementia, aged' 65 years and over living in 91 civil drinking water areas in Southern France. Two measures

Paris-Sud XI, Université de

405

Decomposition of cumyl hydroperoxide in the presence of sulphonated silica in a flow-type system  

SciTech Connect (OSTI)

An investigation has been made of the decomposition of cumyl hydroperoxide (CHP) in the presence of silica-based sulphocationites in a flow-type system. It was established that the given specimens are effective catalysts for the decomposition of CHP into phenol and acetone. It was shown that, in the course of the process, no irreversible poisoning of the surface of the catalyst by the products of CHP decomposition occurs. Data of chromatographic analysis of the products of CHP decomposition in the presence of sulphuric acid and silica-based sulphocationites are given.

Shelpakova, N.A.; Ioffa, A.F.

1993-12-31T23:59:59.000Z

406

Applications of Geothermally-Produced Colloidal Silica in Reservoir Management - Smart Gels  

SciTech Connect (OSTI)

In enhanced geothermal systems (EGS) the reservoir permeability is often enhanced or created using hydraulic fracturing. In hydraulic fracturing, high fluid pressures are applied to confined zones in the subsurface usually using packers to fracture the host rock. This enhances rock permeability and therefore conductive heat transfer to the circulating geothermal fluid (e.g. water or supercritical carbon dioxide). The ultimate goal is to increase or improve the thermal energy production from the subsurface by either optimal designs of injection and production wells or by altering the fracture permeability to create different zones of circulation that can be exploited in geothermal heat extraction. Moreover, hydraulic fracturing can lead to the creation of undesirable short-circuits or fast flow-paths between the injection and extraction wells leading to a short thermal residence time, low heat recovery, and thus a short-life of the EGS. A potential remedy to these problems is to deploy a cementing (blocking, diverting) agent to minimize short-cuts and/or create new circulation cells for heat extraction. A potential diverting agent is the colloidal silica by-product that can be co-produced from geothermal fluids. Silica gels are abundant in various surface and subsurface applications, yet they have not been evaluated for EGS applications. In this study we are investigating the benefits of silica gel deployment on thermal response of an EGS, either by blocking short-circuiting undesirable pathways as a result of diverting the geofluid to other fractures; or creating, within fractures, new circulation cells for harvesting heat through newly active surface area contact. A significant advantage of colloidal silica is that it can be co-produced from geothermal fluids using an inexpensive membrane-based separation technology that was developed previously using DOE-GTP funding. This co-produced silica has properties that potentially make it useful as a fluid diversion agent for subsurface applications. Colloidal silica solutions exist as low-viscosity fluids during their “induction period” but then undergo a rapid increase in viscosity (gelation) to form a solid gel. The length of the induction period can be manipulated by varying the properties of the solution, such as silica concentration and colloid size. We believe it is possible to produce colloidal silica gels suitable for use as diverting agents for blocking undesirable fast-paths which result in short-circuiting the EGS once hydraulic fracturing has been deployed. In addition, the gels could be used in conventional geothermal fields to increase overall energy recovery by modifying flow.

Hunt, Jonathan

2013-01-31T23:59:59.000Z

407

The exchange rate for tritiated water vapor adsorbed on silica gel  

E-Print Network [OSTI]

THE EXCHANGE RATE FOR TRITIATED WATER VAPOR ADSORBED ON SILICA GEL A Thesis by PENNY ALANE SHAMBLIN Submitted to the Cnaduate College of Texas A8cM University in partial fulfihmnt of the requirements for the degree of MASTER OF SCIENCE... December 1987 Major Subject: Health Physics THE EXCHANGE RATE FOR ~TED WATER VAPOR ADSORBED ON SILICA GEL A Thesis by PENNY ALANE SHAMBUN Approved as to style and content by: Milton E. McLain (Chair of Committee) Gerald A. Schla (Member) Ric ard...

Shamblin, Penny Alane

2012-06-07T23:59:59.000Z

408

Applications of Geothermally-Produced Colloidal Silica in Reservoir Management - Smart Gels  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

In enhanced geothermal systems (EGS) the reservoir permeability is often enhanced or created using hydraulic fracturing. In hydraulic fracturing, high fluid pressures are applied to confined zones in the subsurface usually using packers to fracture the host rock. This enhances rock permeability and therefore conductive heat transfer to the circulating geothermal fluid (e.g. water or supercritical carbon dioxide). The ultimate goal is to increase or improve the thermal energy production from the subsurface by either optimal designs of injection and production wells or by altering the fracture permeability to create different zones of circulation that can be exploited in geothermal heat extraction. Moreover, hydraulic fracturing can lead to the creation of undesirable short-circuits or fast flow-paths between the injection and extraction wells leading to a short thermal residence time, low heat recovery, and thus a short-life of the EGS. A potential remedy to these problems is to deploy a cementing (blocking, diverting) agent to minimize short-cuts and/or create new circulation cells for heat extraction. A potential diverting agent is the colloidal silica by-product that can be co-produced from geothermal fluids. Silica gels are abundant in various surface and subsurface applications, yet they have not been evaluated for EGS applications. In this study we are investigating the benefits of silica gel deployment on thermal response of an EGS, either by blocking short-circuiting undesirable pathways as a result of diverting the geofluid to other fractures; or creating, within fractures, new circulation cells for harvesting heat through newly active surface area contact. A significant advantage of colloidal silica is that it can be co-produced from geothermal fluids using an inexpensive membrane-based separation technology that was developed previously using DOE-GTP funding. This co-produced silica has properties that potentially make it useful as a fluid diversion agent for subsurface applications. Colloidal silica solutions exist as low-viscosity fluids during their “induction period” but then undergo a rapid increase in viscosity (gelation) to form a solid gel. The length of the induction period can be manipulated by varying the properties of the solution, such as silica concentration and colloid size. We believe it is possible to produce colloidal silica gels suitable for use as diverting agents for blocking undesirable fast-paths which result in short-circuiting the EGS once hydraulic fracturing has been deployed. In addition, the gels could be used in conventional geothermal fields to increase overall energy recovery by modifying flow.

Hunt, Jonathan

409

Method and composition in which metal hydride particles are embedded in a silica network  

DOE Patents [OSTI]

A silica embedded metal hydride composition and a method for making such a composition. The composition is made via the following process: A quantity of fumed silica is blended with water to make a paste. After adding metal hydride particles, the paste is dried to form a solid. According to one embodiment of the invention, the solid is ground into granules for use of the product in hydrogen storage. Alternatively, the paste can be molded into plates or cylinders and then dried for use of the product as a hydrogen filter. Where mechanical strength is required, the paste can be impregnated in a porous substrate or wire network.

Heung, Leung K. (Aiken, SC)

1999-01-01T23:59:59.000Z

410

Determination of alpha-amylase activity in dextran, ficoll and polyethylene glycol solutions  

Science Journals Connector (OSTI)

A new insoluble chromolytic substrate for the spectrophotometric determination of alpha-amylase activity (starch cross-linked with 1,4 ... phase-forming polymers interfere with some commonly used alpha-amylase as...

Ivo Šafa?ík; Miroslava Šafa?íková

411

Polymer quenched prealloyed metal powder  

DOE Patents [OSTI]

A powder metallurgical process of preparing a sheet from a powder having an intermetallic alloy composition such as an iron, nickel or titanium aluminide. The sheet can be manufactured into electrical resistance heating elements having improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The iron aluminide has an entirely ferritic microstructure which is free of austenite and can include, in weight %, 4 to 32% Al, and optional additions such as .ltoreq.1% Cr, .gtoreq.0.05% Zr .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Ni, .ltoreq.0.75% C, .ltoreq.0.1% B, .ltoreq.1% submicron oxide particles and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, and/or .ltoreq.3 % Cu. The process includes forming a non-densified metal sheet by consolidating a powder having an intermetallic alloy composition such as by roll compaction, tape casting or plasma spraying, forming a cold rolled sheet by cold rolling the non-densified metal sheet so as to increase the density and reduce the thickness thereof and annealing the cold rolled sheet. The powder can be a water, polymer or gas atomized powder which is subjecting to sieving and/or blending with a binder prior to the consolidation step. After the consolidation step, the sheet can be partially sintered. The cold rolling and/or annealing steps can be repeated to achieve the desired sheet thickness and properties. The annealing can be carried out in a vacuum furnace with a vacuum or inert atmosphere. During final annealing, the cold rolled sheet recrystallizes to an average grain size of about 10 to 30 .mu.m. Final stress relief annealing can be carried out in the B2 phase temperature range.

Hajaligol, Mohammad R. (Midlothian, VA); Fleischhauer, Grier (Midlothian, VA); German, Randall M. (State College, PA)

2001-01-01T23:59:59.000Z

412

Achieving High Performance Polymer Tandem Solar Cells via Novel Materials Design  

E-Print Network [OSTI]

polymer solar cell could be a viable technology for spacetechnology must utilize the uniqueness of polymer solar cells.

Dou, Letian

2014-01-01T23:59:59.000Z

413

Modeling Cold Start in a Polymer-Electrolyte Fuel Cell  

E-Print Network [OSTI]

Boundary conditions used for fuel—cell simulations. 3.12to the Problem of Cold Start 1.1 Polymer—Electrolyte Fuelin Polymer Electrolyte Fuel Cells — II. Parametric Study,”

Balliet, Ryan

2010-01-01T23:59:59.000Z

414

New functional polymers for sensors, smart materials and solar cells  

E-Print Network [OSTI]

Organic polymers can be used as the active component of sensors, smart materials, chemical-delivery systems and the active layer of solar cells. The rational design and modification of the chemical structure of polymers ...

Lobez Comeras, Jose Miguel

2012-01-01T23:59:59.000Z

415

Molecular Structures of Polymer/Sulfur Composites for Lithium...  

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

Structures of PolymerSulfur Composites for Lithium-Sulfur Batteries with Long Cycle Life. Molecular Structures of PolymerSulfur Composites for Lithium-Sulfur Batteries with Long...

416

Phase selectively soluble polymer supports to facilitate homogeneous catalysis  

E-Print Network [OSTI]

Soluble polymers that have phase selective solubility are useful in synthesis because they simplify purification and separation. Such selectively soluble polymers simplify catalyst, reagent, and product recovery and enable the use of Green chemistry...

Ortiz-Acosta, Denisse

2009-05-15T23:59:59.000Z

417

Synthesis and Characterization of Polymer Nanocomposites for Energy Applications  

E-Print Network [OSTI]

Polymer nanocomposites are used in a variety of applications due to their good mechanical properties. Specifically, better performance of lithium ion batteries and thermal interface material can be obtained by using conductive materials and polymer...

Park, Wonchang

2011-10-21T23:59:59.000Z

418

Polymer-coated iron oxide nanoparticles for medical imaging  

E-Print Network [OSTI]

One of the most versatile and safe materials used in medicine are polymer-coated iron oxide nanoparticles. This dissertation describes several formulations for in vivo imaging applications. The paramagnetic polymer-coated ...

Chen, Suelin, Ph.D. Massachusetts Institute of Technology

2010-01-01T23:59:59.000Z

419

Tailoring the Thermoelectric Behavior of Electrically Conductive Polymer Composites  

E-Print Network [OSTI]

fabrication temperatures. These concerns have led research efforts into electrically conductive polymer composites prepared in ambient conditions from aqueous solutions. By combining polymer latex with carbon nanotubes (CNT), electrical conductivity can...

Moriarty, Gregory P.

2013-05-21T23:59:59.000Z

420

Processing and thermal properties of molecularly oriented polymers  

E-Print Network [OSTI]

High molecular weight polymers that are linear in molecular construction can be oriented such that some of their physical properties in the oriented direction are enhanced. For over 50 years polymer orientation and processing ...

Skow, Erik (Erik Dean)

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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

Switchable window based on electrochromic polymers Chunye Xu,a)  

E-Print Network [OSTI]

Switchable window based on electrochromic polymers Chunye Xu,a) Lu Liu, Susan E. Legenski, Dai Ning March 2004) A large contrast ratio (> 60%) and rapid switching (0.3­1 s) electrochromic (EC) polymer

Taya, Minoru

422

An overview of molten polymer drawing instabilities Yves Demay1  

E-Print Network [OSTI]

dissipation in a screw/barrel device and then forced in a spinning pack consisting of a metal plaque of processes for polymer film production: · In the cast-film process, the polymer is melted in an extruder

Paris-Sud XI, Université de

423

Biology and polymer physics at the single–molecule level  

Science Journals Connector (OSTI)

...Olmsted Biology and polymer physics at the single-molecule level Steven Chu Department of Physics...be hidden from view can be clearly seen in single-molecule experiments. single-molecule biology|polymer dynamics|biological physics...

2003-01-01T23:59:59.000Z

424

Aliphatic Polyester Block Polymers: Renewable, Degradable, and Sustainable  

Science Journals Connector (OSTI)

Aliphatic Polyester Block Polymers: Renewable, Degradable, and Sustainable ... Yet, such polymers are “challenged” with respect to sustainability. ... The Earth harbors finite carbon-based feedstocks that are being rapidly depleted by our increasing energy demand. ...

Marc A. Hillmyer; William B. Tolman

2014-05-22T23:59:59.000Z

425

Polymer blends for use in photoelectrochemical cells for conversion of solar energy to electricity  

DOE Patents [OSTI]

There is disclosed a polymer blend of a highly conductive polymer and a solid polymer electrolyte that is designed to achieve better charge transfer across the conductive film/polymer electrolyte interface of the electrochemical photovoltaic cell. The highly conductive polymer is preferably polypyrrole or poly-N-p-nitrophenylpyrrole and the solid polymer electrolyte is preferably polyethylene oxide or polypropylene oxide.

Skotheim, T.

1984-09-28T23:59:59.000Z

426

Polymer blends for use in photoelectrochemical cells for conversion of solar energy to electricity  

DOE Patents [OSTI]

There is disclosed a polymer blend of a highly conductive polymer and a solid polymer electrolyte that is designed to achieve better charge transfer across the conductive film/polymer electrolyte interface of the electrochemical photovoltaic cell. The highly conductive polymer is preferably polypyrrole or poly-N-p-nitrophenylpyrrole and the solid polymer electrolyte is preferably polyethylene oxide or polypropylene oxide.

Skotheim, Terje (East Patchogue, NY)

1986-01-01T23:59:59.000Z

427

Polymer Technology Corp | Open Energy Information  

Open Energy Info (EERE)

Polymer Technology Corp Polymer Technology Corp Jump to: navigation, search Name Polymer Technology Corp Place Menomonie, Wisconsin Zip 54751 Sector Services Product A provider of contract engineering services Coordinates 44.8805°, -91.929559° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":44.8805,"lon":-91.929559,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

428

NETL: Novel Inorganic/Polymer Composite Membranes  

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

Novel Inorganic/Polymer Composite Membranes Novel Inorganic/Polymer Composite Membranes Project No.: DE-FE0007632 Ohio State University is developing a cost-effective design and manufacturing process for new membrane modules that capture carbon dioxide (CO2) from flue gas. The membranes consist of a thin, selective inorganic layer, embedded in a polymer structure so that it can be made in a continuous manufacturing process. They will be incorporated in spiral-wound modules for bench-scale tests using coal-fired flue gas. Preliminary cost calculations show that a single-stage membrane process is economically unfavorable, primarily because of the low concentration of CO2 (~14 percent) in the flue gas stream. A two-stage process is more economical, but requires plant operation with a CO2-enriched recycle stream.

429

Adjustable flow rate controller for polymer solutions  

DOE Patents [OSTI]

An adjustable device for controlling the flow rate of polymer solutions which results in only little shearing of the polymer molecules, said device comprising an inlet manifold, an outlet manifold, a plurality of tubes capable of providing communication between said inlet and outlet manifolds, said tubes each having an internal diameter that is smaller than that of the inlet manifold and large enough to insure that viscosity of the polymer solution passing through each said tube will not be reduced more than about 25 percent, and a valve associated with each tube, said valve being capable of opening or closing communication in that tube between the inlet and outlet manifolds, each said valve when fully open having a diameter that is substantially at least as great as that of the tube with which it is associated.

Jackson, Kenneth M. (Bartlesville, OK)

1981-01-01T23:59:59.000Z

430

Two Dimensional Polymer That Generates Nitric Oxide.  

DOE Patents [OSTI]

A polymeric composition that generates nitric oxide and a process for rendering the surface of a substrate nonthrombogenic by applying a coating of the polymeric composition to the substrate are disclosed. The composition comprises: (1) a crosslinked chemical combination of (i) a polymer having amino group-containing side chains along a backbone forming the polymer, and (ii) a crosslinking agent containing functional groups capable of reacting with the amino groups; and (2) a plurality of nitric oxide generating functional groups associated with the crosslinked chemical combination. Once exposed to a physiological environment, the coating generates nitric oxide thereby inhibiting platelet aggregation. In one embodiment, the nitric oxide generating functional groups are provided by a nitrated compound (e.g., nitrocellulose) imbedded in the polymeric composition. In another embodiment, the nitric oxide generating functional groups comprise N2O2- groups covalently bonded to amino groups on the polymer.

McDonald, William F. (Utica, OH); Koren, Amy B. (Lansing, MI)

2005-10-04T23:59:59.000Z

431

Stretchable polymer-based electronic device  

DOE Patents [OSTI]

A stretchable electronic circuit or electronic device and a polymer-based process to produce a circuit or electronic device containing a stretchable conducting circuit. The stretchable electronic apparatus has a central longitudinal axis and the apparatus is stretchable in a longitudinal direction generally aligned with the central longitudinal axis. The apparatus comprises a stretchable polymer body and at least one circuit line operatively connected to the stretchable polymer body. The circuit line extends in the longitudinal direction and has a longitudinal component that extends in the longitudinal direction and has an offset component that is at an angle to the longitudinal direction. The longitudinal component and the offset component allow the apparatus to stretch in the longitudinal direction while maintaining the integrity of the circuit line.

Maghribi, Mariam N. (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA); Davidson, James Courtney (Livermore, CA); Wilson, Thomas S. (Castro Valley, CA); Hamilton, Julie K. (Tracy, CA); Benett, William J. (Livermore, CA); Tovar, Armando R. (San Antonio, TX)

2008-02-26T23:59:59.000Z

432

Thermal diffusivity measurement system applied to polymers  

Science Journals Connector (OSTI)

In the search for cleaner energy sources the improvement of the efficiency of the actual ones appears as a primary objective. In this way thermoelectric materials which are able to convert wasted heat into electricity are reveal as an interesting way to improve efficiency of car engines for example. Cost-effective energy harvesting from thermoelectric devices requires materials with high electrical conductivities and Seebeck coefficient but low thermal conductivity. Conductive polymers can fulfil these conditions if they are doped appropriately. One of the most promising polymers is Polyaniline. In this work the thermal conductivity of the polyaniline and mixtures of polyaniline with nanoclays has been studied using a new experimental set-up developed in the lab. The novel system is based on the steady-state method and it is used to obtain the thermal diffusivity of the polymers and the nanocomposites.

2012-01-01T23:59:59.000Z

433

Tensile Fracture of Welded Polymer Interfaces: Miscibility, Entanglements and Crazing  

E-Print Network [OSTI]

Large-scale molecular simulations are performed to investigate tensile failure of polymer interfaces as a function of welding time $t$. Changes in the tensile stress, mode of failure and interfacial fracture energy $G_I$ are correlated to changes in the interfacial entanglements as determined from Primitive Path Analysis. Bulk polymers fail through craze formation, followed by craze breakdown through chain scission. At small $t$ welded interfaces are not strong enough to support craze formation and fail at small strains through chain pullout at the interface. Once chains have formed an average of about one entanglement across the interface, a stable craze is formed throughout the sample. The failure stress of the craze rises with welding time and the mode of craze breakdown changes from chain pullout to chain scission as the interface approaches bulk strength. The interfacial fracture energy $G_I$ is calculated by coupling the simulation results to a continuum fracture mechanics model. As in experiment, $G_I$ increases as $t^{1/2}$ before saturating at the average bulk fracture energy $G_b$. As in previous simulations of shear strength, saturation coincides with the recovery of the bulk entanglement density. Before saturation, $G_I$ is proportional to the areal density of interfacial entanglements. Immiscibiltiy limits interdiffusion and thus suppresses entanglements at the interface. Even small degrees of immisciblity reduce interfacial entanglements enough that failure occurs by chain pullout and $G_I \\ll G_b$.

Ting Ge; Gary S. Grest; Mark O. Robbins

2014-10-07T23:59:59.000Z

434

Demonstration of Mixed Waste Debris Macroencapsulation Using Sulfur Polymer Cement  

SciTech Connect (OSTI)

This report covers work performed during FY 1997 as part of the Evaluation of Sulfur Polymer Cement Fast-Track System Project. The project is in support of the ``Mercury Working Group/Mercury Treatment Demonstrations - Oak Ridge`` and is described in technical task plan (TTP) OR-16MW-61. Macroencapsulation is the treatment technology required for debris by the U.S. Environmental Protection Agency Land Disposal Restrictions (LDR) under the Resource Conservation and Recovery Act. Based upon the results of previous work performed at Oak Ridge, the concept of using sulfur polymer cement (SPC) for this purpose was submitted to the Mixed Waste Focus Area (MWFA). Because of the promising properties of the material, the MWFA accepted this Quick Win project, which was to demonstrate the feasibility of macroencapsulation of actual mixed waste debris stored on the Oak Ridge Reservation. The waste acceptance criteria from Envirocare, Utah, were chosen as a standard for the determination of the final waste form produced. During this demonstration, it was shown that SPC was a good candidate for macroencapsulation of mixed waste debris, especially when the debris pieces were dry. The matrix was found to be quite easy to use and, once the optimum operating conditions were identified, very straightforward to replicate for batch treatment. The demonstration was able to render LDR compliant more than 400 kg of mixed wastes stored at the Oak Ridge National Laboratory.

Mattus, C.H.

1998-07-01T23:59:59.000Z

435

Polymer-electrolyte membrane, electrochemical fuel cell, and related method  

DOE Patents [OSTI]

A polymer-electrolyte membrane is presented. The polymer-electrolyte membrane comprises an acid-functional polymer, and an additive incorporated in at least a portion of the membrane. The additive comprises a fluorinated cycloaliphatic additive, a hydrophobic cycloaliphatic additive, or combinations thereof, wherein the additive has a boiling point greater than about 120.degree. C. An electrochemical fuel cell including the polymer-electrolyte membrane, and a related method, are also presented.

Krishnan, Lakshmi; Yeager, Gary William; Soloveichik, Grigorii Lev

2014-12-09T23:59:59.000Z

436

Controlled Self Assembly of Conjugated Polymer Containing Block Copolymers  

E-Print Network [OSTI]

Copolymers for Organic Optoelectronics. Macromolecules 2009,Copolymers for Organic Optoelectronics. Macromolecules 2009,performance of polymer optoelectronics. Table of Contents

McCulloch, Bryan

2012-01-01T23:59:59.000Z

437

CX-003342: Categorical Exclusion Determination | Department of Energy  

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

42: Categorical Exclusion Determination 42: Categorical Exclusion Determination CX-003342: Categorical Exclusion Determination High Temperature, Low Relative Humidity Polymer-Type Membranes CX(s) Applied: A9, B3.6 Date: 08/13/2010 Location(s): Arizona Office(s): Energy Efficiency and Renewable Energy, Golden Field Office The objective of this project is to develop high temperature low humidity polymer electrolyte membrane materials based on a solvent-free protic-salt concept. While the project is changing locations, the project goals have not changed since the original National Environmental Policy Act (NEPA) determination. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-003342.pdf More Documents & Publications CX-003348: Categorical Exclusion Determination CX-002457: Categorical Exclusion Determination

438

Polymer-assisted deposition of films  

DOE Patents [OSTI]

A polymer assisted deposition process for deposition of metal nitride films and the like is presented. The process includes solutions of one or more metal precursor and soluble polymers having binding properties for the one or more metal precursor. After a coating operation, the resultant coating is heated at high temperatures under a suitable atmosphere to yield metal nitride films and the like. Such films can be conformal on a variety of substrates including non-planar substrates. In some instances, the films can be epitaxial in structure and can be of optical quality. The process can be organic solvent-free.

McCleskey,Thomas M. (Los Alamos, NM); Burrell,Anthony K. (Los Alamos, NM); Jia,Quanxi (Los Alamos, NM); Lin,Yuan (Chandler, AZ)

2012-02-28T23:59:59.000Z

439

Enhancement in hydrophobicity of silica films using metal acetylacetonate and heat treatment  

Science Journals Connector (OSTI)

Water is one of the most affecting chemicals that can cause damage to the solid surface. To protect the surface due to the action of water, the surface should be made hydrophobic. In the present study, the improvement in hydrophobicity of silica films using metal acetylacetonate (M-acac) by employing heat treatment to methyltrimethoxy silane (MTMS) based silica coatings is reported as a novel attempt. Instead of following the established trends of the surface derivatization or co-precursor method, iron acetylacetonate Fe(acac)3, copper acetylacetonate Cu(acac)2 and heat treatment were used to incorporate hydrophobicity with silica coatings. As M-acac is readily soluble in organic solvents, Fe(acac)3 and Cu(acac)2 were dissolved in methanol (MeOH) and their concentration was varied from 0 to 0.025 M. The coating solution was prepared by optimizing molar ratio of MTMS:MeOH:basic H2O to 1:7.15:6.34, respectively. Gelation time (tg) for Cu(acac)2 containing silica sol and that containing Fe(acac)3 were noted to be 30 and 55 min, respectively. The substrates were taken out after gelation and heat treated at 150 °C for 2 h. The heat treated films showed a dramatic increase in the static water contact angle from 82° to as high as 142°.

Sunetra L. Dhere; Uzma K.H. Bangi; Sanjay S. Latthe; A. Venkateswara Rao

2011-01-01T23:59:59.000Z

440

Density hysteresis of heavy water confined in a nanoporous silica matrix  

E-Print Network [OSTI]

A neutron scattering technique was developed to measure the density of heavy water confined in a nanoporous silica matrix in a temperature-pressure range, from 300 to 130 K and from 1 to 2,900 bars, where bulk water will ...

Zhang, Yang

Note: This page contains sample records for the topic "determination silica polymer" 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

Helium irradiation effects in polycrystalline Si, silica, and single crystal Si  

SciTech Connect (OSTI)

Transmission electron microscopy (TEM) has been used to investigate the effects of room temperature 6 keV helium ion irradiation of a thin ({approx_equal}55 nm thick) tri-layer consisting of polycrystalline Si, silica, and single-crystal Si. The ion irradiation was carried out in situ within the TEM under conditions where approximately 24% of the incident ions came to rest in the specimen. This paper reports on the comparative development of irradiation-induced defects (primarily helium bubbles) in the polycrystalline Si and single-crystal Si under ion irradiation and provides direct measurement of a radiation-induced increase in the width of the polycrystalline layer and shrinkage of the silica layer. Analysis using TEM and electron energy-loss spectroscopy has led to the hypothesis that these result from helium-bubble-induced swelling of the silicon and radiation-induced viscoelastic flow processes in the silica under the influence of stresses applied by the swollen Si layers. The silicon and silica layers are sputtered as a result of the helium ion irradiation; however, this is estimated to be a relatively minor effect with swelling and stress-related viscoelastic flow being the dominant mechanisms of dimensional change.

Abrams, K. J.; Greaves, G.; Berg, J. A. van den [Materials and Physics Research Centre, University of Salford, Salford (United Kingdom); Hinks, J. A.; Donnelly, S. E. [School of Computing and Engineering, University of Huddersfield, Huddersfield (United Kingdom); Pawley, C. J. [Materials and Physics Research Centre, University of Salford, Salford (United Kingdom); School of Computing and Engineering, University of Huddersfield, Huddersfield (United Kingdom); Eyidi, D. [Institut Pprime, Universite de Poitiers, Poitiers (France); Ward, M. B. [Institute for Materials Research, University of Leeds, Leeds (United Kingdom)

2012-04-15T23:59:59.000Z

442

EFFECTS OF SAND AND SILICA FUME ON THE VIBRATION DAMPING BEHAVIOR OF CEMENT  

E-Print Network [OSTI]

. The silica fume (Elkem Materials, Inc., Pittsburgh, PA, EMS 965) was used in the amount of 15% by weight 14260-4400, USA (Received February 6, 1998; in final form June 26, 1998) ABSTRACT The addition of sand. 10, pp. 1353­1356, 1998 Copyright © 1998 Elsevier Science Ltd Printed in the USA. All rights reserved

Chung, Deborah D.L.

443

The fatigue of high-strength fused silica optical fibers in low humidity q  

E-Print Network [OSTI]

the effect of humidity on the kinetics of subcritical crack growth in high strength optical fibers that the rate of subcritical crack growth is given by dc dt ¼ A exp n KI KIC ; ð1� where A and n are fatigue by assuming a simple chemical kinetics model for fatigue in which the reaction rate between water and silica

Matthewson, M. John

444

Activation energy and entropy of dynamic fatigue of pristine silica optical fibers  

E-Print Network [OSTI]

, NJ 08 854-8065 ABSTRACT Subcritical crack growth in fused silica can be modeled as a stress assisted chemical reaction between water and strained bonds at the crack tip. The stress influences the crack growth which has been most commonly used for brittle ceramic materials is the well-known subcritical crack

Matthewson, M. John

445

CHEMICAL KINETICS MODELS FOR THE FATIGUE BEHAVIOR OF FUSED SILICA OPTICAL FIBER  

E-Print Network [OSTI]

of stress, temperature and activity of the corroding species (e.g. water). A power law degradation kinetics the degradation depends on the applied stress. Subcritical Crack Growth Model The reliability of silica optical fiber under stress is usually described by the subcritical crack growth model. It is assumed

Matthewson, M. John

446

Silica entrapment for significantly stabilized, energy-conducting light-harvesting complex (LHCII)  

Science Journals Connector (OSTI)

Silica entrapment for significantly stabilized, energy-conducting light-harvesting complex (LHCII) ... The entrapped LHCII stayed functional at 50 °C for up to 24 h instead of a few minutes in detergent solution and clearly showed energy transfer between complexes. ...

Sebastian Röder; Stephan Hobe; Harald Paulsen

2014-11-03T23:59:59.000Z

447

Spectroscopic Studies of Atmospheric Relevant Air-Aqueous and Air-Silica DISSERTATION  

E-Print Network [OSTI]

process in the atmosphere. As models of these phenomena, interfacial water vapor uptake by #12;iii to the air-water interface were examined. Sum frequency generation (SFG), a surface specific techniqueSpectroscopic Studies of Atmospheric Relevant Air-Aqueous and Air-Silica Interfaces DISSERTATION

448

Additive-Driven Dissolution Enhancement of Colloidal Silica. 3. Fluorine-Containing Additives  

Science Journals Connector (OSTI)

Add to ACS ChemWorx ... Among the former are silica removal by ion-exchange methods(13) and utilization of scale inhibitors. ... Therefore, we would like to broaden the scope of the potential utilization of fluorine-containing additives with the objective that a broader choice of additive selection will be available to end-users. ...

Konstantinos D. Demadis; Maria Somara; Eleftheria Mavredaki

2012-01-20T23:59:59.000Z

449

Silica–titania aerogel monoliths with large pore volume and surface area by ambient pressure drying  

Science Journals Connector (OSTI)

Ambient pressure drying has been carried out for the synthesis of silica–titania aerogel monoliths. The prepared aerogels show densities in the range 0.34–0.38 g/cm3. The surface area and pore volume of these mix...

P. R. Aravind; P. Shajesh; P. Mukundan…

2009-12-01T23:59:59.000Z

450

Production of silica aerogel microparticles loaded with ammonia borane by batch and semicontinuous supercritical drying techniques  

Science Journals Connector (OSTI)

Abstract Silica aerogel microparticles were prepared by supercritical drying and used as support for hydrogen-storing ammonia borane (AB). The formation of aerogel microparticles was done using two different processes: batch supercritical fluid extraction and a semicontinuous drying process. Silica aerogel microparticles with a surface area ranging from 400 to 800 m2/g, a volume of pores of 1 cm3/g, and a mean particle diameter ranging from 12 to 27 ?m were produced using the two drying techniques. The particle size distribution (PSD) of the microparticles was influenced by shear rate, amount of catalyst, hydrophilic–hydrophobic solvent ratio and hydrophobic surface modification. In particular, irregular aerogel particles were obtained from hydrophilic gels, while regular, spherical particles with smooth surfaces were obtained from hydrophobic gels. AB was loaded into silica aerogel microparticles in concentrations ranging from 1% till 5% wt. Hydrogen release kinetics from the hydride-loaded aerogel was analyzed with a volumetric cell at 80 °C. By stabilization of AB into the silica aerogel microparticles, an improvement of the release rate of hydrogen from AB was observed.

Miriam Rueda; Luis Miguel Sanz-Moral; Antonio Nieto-Márquez; Pablo Longone; Facundo Mattea; Ángel Martín

2014-01-01T23:59:59.000Z

451

Application of stochastic weighted algorithms to a multidimensional silica particle model  

SciTech Connect (OSTI)

Highlights: •Stochastic weighted algorithms (SWAs) are developed for a detailed silica model. •An implementation of SWAs with the transition kernel is presented. •The SWAs’ solutions converge to the direct simulation algorithm’s (DSA) solution. •The efficiency of SWAs is evaluated for this multidimensional particle model. •It is shown that SWAs can be used for coagulation problems in industrial systems. -- Abstract: This paper presents a detailed study of the numerical behaviour of stochastic weighted algorithms (SWAs) using the transition regime coagulation kernel and a multidimensional silica particle model. The implementation in the SWAs of the transition regime coagulation kernel and associated majorant rates is described. The silica particle model of Shekar et al. [S. Shekar, A.J. Smith, W.J. Menz, M. Sander, M. Kraft, A multidimensional population balance model to describe the aerosol synthesis of silica nanoparticles, Journal of Aerosol Science 44 (2012) 83–98] was used in conjunction with this coagulation kernel to study the convergence properties of SWAs with a multidimensional particle model. High precision solutions were calculated with two SWAs and also with the established direct simulation algorithm. These solutions, which were generated using large number of computational particles, showed close agreement. It was thus demonstrated that SWAs can be successfully used with complex coagulation kernels and high dimensional particle models to simulate real-world systems.

Menz, William J. [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA (United Kingdom)] [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA (United Kingdom); Patterson, Robert I.A.; Wagner, Wolfgang [Weierstrass Institute for Applied Analysis and Stochastics, Mohrenstrasse 39, Berlin 10117 (Germany)] [Weierstrass Institute for Applied Analysis and Stochastics, Mohrenstrasse 39, Berlin 10117 (Germany); Kraft, Markus, E-mail: mk306@cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA (United Kingdom)] [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA (United Kingdom)

2013-09-01T23:59:59.000Z

452

Enhanced green upconversion luminescence in Yb–Tb co-doped sintered silica nanoporous glass  

Science Journals Connector (OSTI)

We report on a new kind of green-emitting (543 nm) high-silica luminous...3+–Tb3+...co-doped nanoporous glass. The fluorescence spectra show that there is an energy transfer between Yb3+ and Tb3+. The energy tran...

Yingbo Chu; Yu Yang; Zijun Liu; Lei Liao; Yibo Wang; Jiaming Li…

2014-11-01T23:59:59.000Z

453

Heavy metal phosphate nanophases in silica: influence of radiolysis probed via f-electron state properties  

SciTech Connect (OSTI)

We have assessed the feasibility of carrying out time- and wavelength-resolved laser-induced fluorescence measurements of radiation damage in glassy silica. The consequences of alpha decay of Es-253 in LaPO{sub 4} nanophases embedded in silica were probed based on excitation of 5f states of Cm{sup 3+}, Bk{sup 3+}, and Es{sup 3+} ions. The recorded emission spectra and luminescence decays showed that alpha decay of Es-253 ejected Bk-249 decay daughter ions into the surrounding silica and created radiation damage within the LaPO{sub 4} nanophases. This conclusion is consistent with predictions of an ion transport code commonly used to model ion implantation. Luminescence from the {sup 6}D{sub 7/2} state of Cm{sup 3+}was used as an internal standard. Ion-ion energy transfer dominated the dynamics of the observed emitting 5f states and strongly influenced the intensity of observed spectra. In appropriate sample materials, laser-induced fluorescence provides a powerful method for fundamental investigation of alpha-induced radiation damage in silica.

Beitz, James V. [Chemistry Division, 9700 South Cass Avenue, Argonne National Laboratory, Argonne, IL 60439-4831 (United States)]. E-mail: beitz@anl.gov; Williams, C.W. [Chemistry Division, 9700 South Cass Avenue, Argonne National Laboratory, Argonne, IL 60439-4831 (United States); Hong, K.-S. [Chemistry Division, 9700 South Cass Avenue, Argonne National Laboratory, Argonne, IL 60439-4831 (United States); Liu, G.K. [Chemistry Division, 9700 South Cass Avenue, Argonne National Laboratory, Argonne, IL 60439-4831 (United States)

2005-02-15T23:59:59.000Z

454

Fluorescent silica colloids for study and visualization of skin care products  

E-Print Network [OSTI]

due to long exposures to cold and dry air (7). Different skin care products are used to hy- drate dryFluorescent silica colloids for study and visualization of skin care products Swaminathan Iyer: The efficacy of skin care products depends on the time and dynamics of their absorbance by the skin, and its

Sokolov, Igor

455

Effects of Surface Modification Conditions on Hydrophobicity of Silica-based Coating Additives  

SciTech Connect (OSTI)

Superhydrophobic silica (SHS) powders are being evaluated as a potential additive to the polyurethane topcoats used in Chemical Agent Resistant Coating (CARC) systems, with the goal of improving water repellency and corrosion protection characteristics. The current generation of CARC topcoats is already highly loaded with solids, and thus there is a premium on minimization of the total SHS powder required to achieve the desired properties. Therefore, efficient surface modification of the silica and proper dispersion in the coating will be required. The effect of a dispersant on the surface modification of silica particles by chlorosilanes was addressed in this study. The properties of various SHS powders were characterized by thermogravimetric analysis and mass spectroscopy. Correlations between powder modification conditions and the ultimate effects of the modified particles on hydrophobicity of CARC topcoats were assessed. The use of contact and rolling angle measurements along with scanning electron microscopy are discussed as they pertain to the ability to quantify the effects of modified silicas on corrosion prevention coatings. Furthermore, a systematic approach to modifying and testing both powders and top coats of corrosion prevention systems is presented.

Armstrong, Beth L [ORNL] [ORNL; Pawel, Steven J [ORNL] [ORNL; Hunter, Scott Robert [ORNL] [ORNL; Haynes, James A [ORNL] [ORNL; Hillesheim, Daniel A [ORNL] [ORNL

2013-01-01T23:59:59.000Z

456

Oxygen isotope fractionation between amorphous silica and water at 34–93°C  

Science Journals Connector (OSTI)

... , P-3 and P-4) along the reinjection lines in the Otake and Hatchobaru geothermal power plants. Although it would have been preferable to obtain the amorphous silica at ... temperatures, these four points were the only ones available for this experiment. The same geothermal water from the Otake station flows at P-l and P-4; at P- ...

Itsuro Kita; Sachihiro Taguchi; Osamu Matsubaya

1985-03-07T23:59:59.000Z

457

Sodium-Silicate Route to Submicrometer Hybrid PEG@Silica Particles  

Science Journals Connector (OSTI)

Sodium-Silicate Route to Submicrometer Hybrid PEG@Silica Particles ... Supported by the Nano Functional Materials (NFM) MAGNET Program of the Israel Ministry of Trade and Industry, by the Infrastructure (Tashtiot) Program of the Israel Ministry of Science, and by the European Functionalized Advanced Materials and Engineering Hybrids and Ceramic (FAME) Network of Excellence (NOE). ...

Hila Elimelech; David Avnir

2008-03-04T23:59:59.000Z

458

Flame-Retardant Epoxy Resin Nanocomposites Reinforced with Polyaniline-Stabilized Silica Nanoparticles  

E-Print Network [OSTI]

, Henry A. Colorado, Suying Wei,*,# and Zhanhu Guo*, Integrated Composites Lab (ICL), Dan F. Smith silsesquioxanes (POSS) reinforced epoxy composites.10 For the third method, the inorganic nanoparticles are often (ATH),13 silica (SiO2),14 nanoclay,15 and newly developed phosphorus- containing flame retardants 9

Guo, John Zhanhu

459

Thulium-doped silica fibers with enhanced 3 H4 level lifetime  

E-Print Network [OSTI]

of cheap mass production. With the cladding-pump technique, fiber lasers and amplifiers have proven-power, high-brightness laser beams. The most important multi-watt fiber lasers were reported using double-clad at 810 nm can be achieved for specific ranges of the laser cavity parameters in silica-based thulium

Paris-Sud XI, Université de

460

Acidity and catalytic activity of zeolite catalysts bound with silica and alumina  

E-Print Network [OSTI]

. Micropore surface area and micropore volume are reduced by about 19% and 18%, respectively, indicating some micropores of ZSM-5 are blocked on binding with silica. SiO2-bound ZSM-5 catalysts have less catalytic activity for butane transformation (cracking...

Wu, Xianchun

2004-09-30T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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.


461

Alkanethiol-Induced Structural Rearrangements in Silica-Gold Core-Shell-type Nanoparticle Clusters: An  

E-Print Network [OSTI]

Alkanethiol-Induced Structural Rearrangements in Silica-Gold Core-Shell-type Nanoparticle Clusters 21, 2003. In Final Form: April 19, 2004 Electrostatically bonded SiO2,Au nanoparticle clusters form by reaction of 3-aminopropylsilane-modified SiO2 spheres (470 nm) with citrate-coated gold nanoparticles (9

Guo, Ting

462

MODELING THE MEAN INTERACTION FORCES BETWEEN POWDER APPLICATION TO SILICA GEL-MAGNESIUM STEARATE MIXTURES.  

E-Print Network [OSTI]

1 MODELING THE MEAN INTERACTION FORCES BETWEEN POWDER PARTICLES. APPLICATION TO SILICA GEL-MAGNESIUM) particles (d50 = 55 µm) were coated with fine invited particles of magnesium stearate (MS, d50 = 4.6 µm. Interaction forces between the material attached to the cantilever (Magnesium Stearate MS) and the surface

Paris-Sud XI, Université de

463

9422 Stratospheric ice catalyzes chlorine reactions 9428 Fusing silk and silica  

E-Print Network [OSTI]

, at temperatures this high, cirrus cloud formation could also be affected. -- P.D. ``Hydrogen chloride may lead to unique methods of prepar- ing spider silk and producing silica particles with precise in aqueous solutions. Wong Po Foo et al. say their technique may allow the production of other resilient

McFadden, Geoff

464

EPR study of the adsorption of dioxin vapours onto microporous carbons and mesoporous silica  

E-Print Network [OSTI]

EPR study of the adsorption of dioxin vapours onto microporous carbons and mesoporous silica M 31 October 2010 Keywords: EPR AC MTS Surface characterization Dioxin a b s t r a c t Computer aided with a nitroxide radical (TCDD-T) was employed to investigate the adsorption of dioxin vapours onto two carbons

Turro, Nicholas J.

465

Anhydrous Phosphoric Acid Functionalized Sintered Mesoporous Silica Nanocomposite Proton Exchange Membranes for Fuel Cells  

Science Journals Connector (OSTI)

Anhydrous Phosphoric Acid Functionalized Sintered Mesoporous Silica Nanocomposite Proton Exchange Membranes for Fuel Cells ... The cell performance and stability may be further improved through an optimization of the interfacial contact between the electrocatalytic layer and the inorganic membrane. ... polycondensation procedure was optimized for individual case of PBI synthesis in order to obtain inherent viscosity of ?1 dL/g. ...

Jie Zeng; Beibei He; Krystina Lamb; Roland De Marco; Pei Kang Shen; San Ping Jiang

2013-10-14T23:59:59.000Z

466

Study of pure-silica Zeolite Nucleation and Growth from Solution  

E-Print Network [OSTI]

of silica precursor particles with size of 2-5 nm in these mixtures prior to and during hydrothermal treatments have been observed through dynamic light scattering (DLS), small-angle X-ray (SAXS) and transmission electron microscopy (TEM). However...

Li, Xiang

2011-10-21T23:59:59.000Z

467

Apparent activation energy of fused silica optical fibers in static fatigue in aqueous environments  

E-Print Network [OSTI]

to occur when ambient moisture reacts with the fiber surface causing subcritical crack growth.1Ã?3 Fatigue of silica optical fiber is therefore controlled by the crack growth rate, c : , which depends for the crack growth, which was originally proposed by Charles and Hillig, based on simple chemical kinetics

Matthewson, M. John

468

Acoustic and Thermal Characterization of Oil Migration, Gas Hydrates Formation and Silica Diagenesis  

E-Print Network [OSTI]

Acoustic and Thermal Characterization of Oil Migration, Gas Hydrates Formation and Silica Rights Reserved #12;ABSTRACT Acoustic and Thermal Characterization of Oil Migration, Gas Hydrates-A to Opal-CT, the formation of gas hydrates, fluid substitution in hydrocarbon reservoirs, and fluid

Guerin, Gilles

469

Model systems for single molecule polymer Folarin Latinwoa  

E-Print Network [OSTI]

, including synthetic organic polymers. Recently, we developed single stranded DNA (ssDNA) as a new model, the local phys- ical and chemical properties of dsDNA are distinct from common synthetic organic polymer DNA (ssDNA).15 ssDNA is a flexible polymer with local physical properties similar to synthetic organic

Schroeder, Charles

470

Microfluidic devices and methods including porous polymer monoliths  

DOE Patents [OSTI]

Microfluidic devices and methods including porous polymer monoliths are described. Polymerization techniques may be used to generate porous polymer monoliths having pores defined by a liquid component of a fluid mixture. The fluid mixture may contain iniferters and the resulting porous polymer monolith may include surfaces terminated with iniferter species. Capture molecules may then be grafted to the monolith pores.

Hatch, Anson V; Sommer, Gregory J; Singh, Anup K; Wang, Ying-Chih; Abhyankar, Vinay V

2014-04-22T23:59:59.000Z

471

Polymers Promoting Quality by Jung-Il Jin  

E-Print Network [OSTI]

of polymer science. The Polymer Education and International Cooperation sessions provided an opportunity and the total number of presentations, including posters, was slightly more than 1 300 (35 percent Brazilian) for his brilliant effort in bridging polymer science with biological problems. Mr. Hong-Shik Ko, president

Tew, Gregory N.

472

Polymer, Vol. 46, no. 2, pp. 553-562 (2005) Modeling of the Mechanical Properties of Nanoparticle/Polymer Composites  

E-Print Network [OSTI]

and particles in the polymer. Several efforts have focused on the modeling of mechanical properties of nanoclay

Odegard, Gregory M.

473

Silica-polyamine composite materials for heavy metal ion removal, recovery, and recycling. 2. Metal ion separations from mine wastewater and soft metal ion extraction efficiency  

SciTech Connect (OSTI)

Silica-polyamine composites have been synthesized which have metal ion capacities as high as 0.84 mmol/g for copper ions removed from aqueous solutions. In previous reports it has been demonstrated that these materials survive more than 3,000 cycles of metal ion extraction, elution, and regeneration with almost no loss of capacity (less than 10%). This paper describes two modified silica-polyamine composite materials and reveals the results of tests designed to determine the effectiveness of these materials for extracting and separating metal ions from actual mining wastewater samples. Using these materials, the concentration of copper, aluminum, and zinc in Berkeley Pit mine wastewater is reduced to below allowable discharge limits. The recovered copper and zinc solutions were greater than 90% pure, and metal ion concentration factors of over 20 for copper were realized. Further, the ability of one of these materials to decrease low levels of the soft metals cadmium, mercury, and lead from National Sanitation Foundation recommended challenge levels to below Environmental Protection Agency allowable limits is also reported.

Fischer, R.J.; Pang, D.; Beatty, S.T.; Rosenberg, E.

1999-12-01T23:59:59.000Z

474

Spatial Gradients in Particle Reinforced Polymers Characterized by X-Ray Attenuation and Laser Confocal Microscopy  

SciTech Connect (OSTI)

The goal of this work is to develop techniques for measuring gradients in particle concentration within filled polymers, such as encapsulant. A high concentration of filler particles is added to such materials to tailor physical properties such as thermal expansion coefficient. Sedimentation and flow-induced migration of particles can produce concentration gradients that are most severe near material boundaries. Therefore, techniques for measuring local particle concentration should be accurate near boundaries. Particle gradients in an alumina-filled epoxy resin are measured with a spatial resolution of 0.2 mm using an x-ray beam attenuation technique, but an artifact related to the finite diameter of the beam reduces accuracy near the specimen's edge. Local particle concentration near an edge can be measured more reliably using microscopy coupled with image analysis. This is illustrated by measuring concentration profiles of glass particles having 40 {micro}m median diameter using images acquired by a confocal laser fluorescence microscope. The mean of the measured profiles of volume fraction agrees to better than 3% with the expected value, and the shape of the profiles agrees qualitatively with simple theory for sedimentation of monodisperse particles. Extending this microscopy technique to smaller, micron-scale filler particles used in encapsulant for microelectronic devices is illustrated by measuring the local concentration of an epoxy resin containing 0.41 volume fraction of silica.

LAGASSE,ROBERT R.; THOMPSON,KYLE R.

2000-06-12T23:59:59.000Z

475

Extensional rheology of polymers and optical properties of blown polymer films  

E-Print Network [OSTI]

Extensional Rheo logy of Polymers and Optical Properties of Blown Polymer Films. (August 1998) Jason E. Maxey, B. S. , Texas A&M University Chair of Advisory Committee: Dr. Lynden Archer Biaxial extensional flows are a commonly encountered and yet poorly.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Molecular Orientation by Bireiringence . Crystallinity by Raman Spectroscopy. Results and Discussion Film Bireiringence Raman Analysis of Crystallinity . . . . . . . 5 . . . . . 7 . . . . . 7 11 . 13 . . . 13 . . . 18 LUBRICATED SQUEEZING...

Maxey, Jason E

2012-06-07T23:59:59.000Z

476

Brine tolerant polymer for oil recovery applications  

SciTech Connect (OSTI)

This patent describes a beta-alanine-type branched partially hydrolyzed polyacrylamide, which is added to an aqueous injection fluid to increase the viscosity of the fluid. The polymer resists plugging of the wellbore face and/or matrix pores and is brine tolerant when injected into a subterranean hydrocarbon-bearing formation.

Tackett, J.E.

1987-11-24T23:59:59.000Z

477

Semipermeable polymers and method for producing same  

DOE Patents [OSTI]

A polyamide membrane comprising reaction product of an anhydrous solution comprising an anhydrous solvent, at least one polyfunctional secondary amine and a pre-polymer deposition catalyst; and an anhydrous, organic solvent solution comprising a polyfunctional aromatic amine-reactive reactant comprising one ring. A composite semipermeable membrane comprising the polyamide membrane on a porous support. A method of making a composite semipermeable membrane by coating a porous support with an anhydrous solution comprising an anhydrous solvent, a polyfunctional secondary amine and a pre-polymer deposition catalyst, to form an activated pre-polymer layer on the porous support and contacting the activated pre-polymer layer with an anhydrous, organic solvent solution comprising a polyfunctional amine-reactive reactant to interfacially condense the amine-reactive reactant with the polyfunctional secondary amine, thereby forming a cross-linked, interfacial polyamide layer on the porous support. A method of impregnating a composite semipermeable membrane with nanoparticles selected from heavy metals and/or oxides of heavy metals.

Buschmann, Wayne E. (Boulder, CO)

2012-04-03T23:59:59.000Z

478

Water-soluble polymers and compositions thereof  

DOE Patents [OSTI]

Water-soluble polymers including functionalization from the group of amino groups, carboxylic acid groups, phosphonic acid groups, phosphonic ester groups, acylpyrazolone groups, hydroxamic acid groups, aza crown ether groups, oxy crown ethers groups, guanidinium groups, amide groups, ester groups, aminodicarboxylic groups, permethylated polyvinylpyridine groups, permethylated amine groups, mercaptosuccinic acid groups, alkyl thiol groups, and N-alkylthiourea groups are disclosed.

Smith, B.F.; Robison, T.W.; Gohdes, J.W.

1999-04-06T23:59:59.000Z

479

Laminar-turbulent transition in polymer solutions  

Science Journals Connector (OSTI)

... as shown in Fig. Ic. A similar appearance to Fig. Ic was obtained by roughening the surface of the ogive in pure water flow (although we were careful to ... the surface of the ogive in pure water flow (although we were careful to avoid roughening the ogive surface when using polymer solution). Thus, we conclude that the presence ...

J. W. HOYT

1977-12-08T23:59:59.000Z

480

Preparation and characterization of gradient polymer films  

SciTech Connect (OSTI)

Gradient polymers are multicomponent polymers whose chemical constitution varies with depth in the sample. Although these polymers may possess unique mechanical, optical, and barrier properties they remain relatively unexplored. This work is a study of the preparation of gradient polymers by sequential exposure of films to a diffusing monomer followed by electron beam irradiation. Initial experiments involved immersion of poly(vinyl chloride) (PVC) films in styrene or n-butyl methacrylate (BMA) for various time periods followed by irradiation with 1 or 10 megarads of accelerated electrons. A significant amount of poly(n-butyl methacrylate) (PBMA) formed in PVC/BMA systems, but little polystyrene could be found in the PVC/styrene films. A second set of experiments involved immersion of PVC and polyethylene (PE) films in BMA for 20, 40, 60, and 720 minutes followed by irradiation with 10 megarads of electrons. These films were then characterized using optical microscopy, quantitative transmission Fourier transform infrared spectroscopy (FTIR), and a depth profiling procedure based on quantitative attenuated total reflection (ATR) FTIR. It was concluded that the mechanism of PBMA formation in the polyethylene films was a result of events immediately following irradiation. Atmospheric oxygen diffusing into irradiated films trapped free radicals at the film surfaces. This was followed by storage in an evacuated desiccator where unintentional exposure to BMA vapor took place. This BMA reacted with free radicals that remained within the film cores, polymerizing to PBMA.

Smith, S.C.

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "determination silica polymer" 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.


481

Self-organized stiffness in regular fractal polymer structures  

Science Journals Connector (OSTI)

We investigated membrane-like polymer structures of fractal connectivity such as Sierpinski gaskets and Sierpinski carpets applying the bond fluctuation model in three dimensions. Without excluded volume (phantom), both polymeric fractals obey Gaussian elasticity on larger scales determined by their spectral dimension. On the other hand, the swelling effect due to excluded volume is rather distinct between the two polymeric fractals: Self-avoiding Sierpinski gaskets can be described using a Flory-type mean-field argument. Sierpinski carpets having a spectral dimension closer to perfect membranes are significantly more strongly swollen than predicted. Based on our simulation results it cannot be excluded that Sierpinski carpets in athermal solvent show a flat phase on larger scales. We tested the self-consistency of Flory predictions using a virial expansion to higher orders. From this we conclude that the third virial coefficient contributes marginally to Sierpinski gaskets, but higher order virial coefficients are relevant for Sierpinski carpets.

Marco Werner and Jens-Uwe Sommer

2011-05-16T23:59:59.000Z

482

Methods of making composite optical devices employing polymer liquid crystal  

DOE Patents [OSTI]

Composite optical devices are disclosed using polymer liquid crystal materials both as optical and adhesive elements. The devices are made by assembling a heated polymer liquid crystal compound, while in a low viscosity form between optically transparent substrates. The molecules of the polymer are oriented, while in the liquid crystalline state and while above the glass transition temperature (T[sub g]) of the polymer, to provide the desired optical effects, such as polarization, and selective reflection. The liquid crystal polymer cements the substrates together to form an assembly providing the composite optical device. 7 figures.

Jacobs, S.D.; Marshall, K.L.; Cerqua, K.A.

1991-10-08T23:59:59.000Z

483

Methods of making composite optical devices employing polymer liquid crystal  

DOE Patents [OSTI]

Composite optical devices using polymer liquid crystal materials both as optical and adhesive elements. The devices are made by assembling a heated polymer liquid crystal compound, while in a low viscosity form between optically transparent substrates. The molecules of the polymer are oriented, while in the liquid crystalline state and while above the glass transition temperature (T.sub.g) of the polymer, to provide the desired optical effects, such as polarization, and selective reflection. The liquid crystal polymer cements the substrates together to form an assembly providing the composite optical device.

Jacobs, Stephen D. (Pittsford, NY); Marshall, Kenneth L. (Henrietta, NY); Cerqua, Kathleen A. (Fairport, NY)

1991-01-01T23:59:59.000Z

484

Increased Oil Recovery from Mature Oil Fields Using Gelled Polymer Treatments  

SciTech Connect (OSTI)

This report describes the progress of the first year of a three-year research program. This program is aimed at reducing barriers to the widespread use of gelled polymer treatments by (1) developing methods to predict gel behavior during placement in matrix rock and fractures, (2) determining the persistence of permeability reduction after gel placement, and (3) developing methods to design production well treatments to control water production.

Willhite, G.P.; Green, D.W.; McCool, C.S.

2001-01-22T23:59:59.000Z

485

Concentration fluctuations in miscible polymer blends: Influence of temperature and chain rigidity  

SciTech Connect (OSTI)

In contrast to binary mixtures of small molecule fluids, homogeneous polymer blends exhibit relatively large concentration fluctuations that can strongly affect the transport properties of these complex fluids over wide ranges of temperatures and compositions. The spatial scale and intensity of these compositional fluctuations are studied by applying Kirkwood-Buff theory to model blends of linear semiflexible polymer chains with upper critical solution temperatures. The requisite quantities for determining the Kirkwood-Buff integrals are generated from the lattice cluster theory for the thermodynamics of the blend and from the generalization of the random phase approximation to compressible polymer mixtures. We explore how the scale and intensity of composition fluctuations in binary blends vary with the reduced temperature ? ? (T ? T{sub c})/T (where T{sub c} is the critical temperature) and with the asymmetry in the rigidities of the components. Knowledge of these variations is crucial for understanding the dynamics of materials fabricated from polymer blends, and evidence supporting these expectations is briefly discussed.

Dudowicz, Jacek; Freed, Karl F. [The James Franck Institute and the Department of Chemistry, The University of Chicago, Chicago, Illinois 60637 (United States)] [The James Franck Institute and the Department of Chemistry, The University of Chicago, Chicago, Illinois 60637 (United States); Douglas, Jack F. [The James Franck Institute and the Department of Chemistry, The University of Chicago, Chicago, Illinois 60637 (United States) [The James Franck Institute and the Department of Chemistry, The University of Chicago, Chicago, Illinois 60637 (United States); Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

2014-05-21T23:59:59.000Z

486

CX-002965: Categorical Exclusion Determination | Department of Energy  

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

5: Categorical Exclusion Determination 5: Categorical Exclusion Determination CX-002965: Categorical Exclusion Determination Mixed Conducting Corrosion Resistant Materials for Polymer Electrolyte Fuel Cells CX(s) Applied: B3.6 Date: 07/12/2010 Location(s): Illinois Office(s): Energy Efficiency and Renewable Energy, Golden Field Office Illinois Institute of Technology (ITT) is proposing to use Department of Energy funding to conduct research to further advancement of polymer electrolyte fuel cells (PEFC). Bench scale experiments will be performed that will evaluate the properties and accelerated durability of a variety of potentially functional materials for the PEFC. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-002965.pdf More Documents & Publications CX-003150: Categorical Exclusion Determination CX-002951: Categorical Exclusion Determination

487

Dynamics of Conformational Transition in Thermo-Sensitive Polymers and  

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

Atomistic simulations elucidating the coil-to-globule conformational changes in thermosensitive polymers. Atomistic simulations elucidating the coil-to-globule conformational changes in thermosensitive polymers. Atomistic simulations elucidating the coil-to-globule conformational changes in thermosensitive polymers. Dynamics of Conformational Transition in Thermo-Sensitive Polymers and Hydrogels PI Name: Subramanian Sankaranarayanan PI Email: skrssank@anl.gov Institution: Argonne National Laboratory Allocation Program: ALCC Allocation Hours at ALCF: 50 Million Year: 2012 Research Domain: Materials Science Subramanian Sankaranarayanan with Argonne's Center for Nanoscale Materials was awarded 50 million hours to study conformational transformations in thermo-sensitive oligomers and their macroscopic architectures such as polymer brushers and polymer gels. Understanding the conformational transformations of isolated linear polymer

488

Polymers with Tailored Electronic Structure for High Capacity Lithium  

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

Polymers with Tailored Electronic Structure for High Capacity Lithium Polymers with Tailored Electronic Structure for High Capacity Lithium Battery Electrodes Title Polymers with Tailored Electronic Structure for High Capacity Lithium Battery Electrodes Publication Type Journal Article Year of Publication 2011 Authors Liu, Gao, Shidi Xun, Nenad Vukmirovic, Xiangyun Song, Paul Olalde-Velasco, Honghe Zheng, Vince S. Battaglia, Linwang Wang, and Wanli Yang Journal Advanced Materials Volume 23 Start Page 4679 Issue 40 Pagination 4679 - 4683 Date Published 10/2011 Keywords binders, conducting polymers, density funcational theory, lithium batteries, X-ray spectroscopy Abstract A conductive polymer is developed for solving the long-standing volume change issue in lithium battery electrodes. A combination of synthesis, spectroscopy and simulation techniques tailors the electronic structure of the polymer to enable in situ lithium doping. Composite anodes based on this polymer and commercial Si particles exhibit 2100 mAh g-1 in Si after 650 cycles without any conductive additive.

489

ToF-SIMS evaluation of calcium-containing silica/?-PGA hybrid systems for bone regeneration  

Science Journals Connector (OSTI)

Abstract Inorganic/organic hybrids have great potential for the production of bioactive scaffolds which have tailored mechanical properties and degradation rates suitable for tissue engineering. For bone regeneration, calcium incorporation into hybrids at low temperatures is important due to its ability to stimulate new bone formation. As a consequence, understanding the homogeneity of the critical inorganic and organic components will be the key to the development of such hybrids. The aim of this interdisciplinary study was to use time-of-flight secondary ion mass spectrometry (ToF-SIMS) to determine the homogeneity of these critical components. We evaluated various sol–gel silica/?-polyglutamic acid (?-PGA) hybrid systems produced using different routes to introduce the calcium, thereby tailoring and optimizing hybrid syntheses and processing routes. Dimethyl carbonate (DMC) was used to improve the inorganic/organic coupling and its influence on the homogeneity of the hybrid structures was also examined. The results revealed that the calcium salt form of ?-PGA was promising for calcium incorporation since homogeneous products could be obtained. The ToF-SIMS data also indicated that the reaction time of hybrid synthesis and the timing of the addition of DMC can affect the homogeneity of hybrids.

Daming Wang; Jin Nakamura; Gowsihan Poologasundarampillai; Toshihiro Kasuga; Julian R. Jones; David S. McPhail

2014-01-01T23:59:59.000Z

490

Fast-neutron radiation effects in a silica-core optical fiber studied by a CCD-camera spectrometer  

Science Journals Connector (OSTI)

A simple CCD-camera spectrometer was deployed at the Los Alamos Spallation Radiation Effects Facility to characterize fast-neutron irradiation effects in several silica-based optical...

Griscom, D L; Gingerich, M E; Friebele, E J; Putnam, M; Unruh, W

1994-01-01T23:59:59.000Z

491

Near-surface modification of optical properties of fused silica by low-temperature hydrogenous atmospheric pressure plasma  

Science Journals Connector (OSTI)

In this Letter, we report on the near-surface modification of fused silica by applying a hydrogenous atmospheric pressure plasma jet at ambient temperature. A significant decrease in...

Gerhard, Christoph; Tasche, Daniel; Brückner, Stephan; Wieneke, Stephan; Viöl, Wolfgang

2012-01-01T23:59:59.000Z

492

DOI: 10.1002/chem.201203003 A Top-Down Synthesis Route to Ultrasmall Multifunctional Gd-Based Silica  

E-Print Network [OSTI]

-Based Silica Nanoparticles for Theranostic Applications Anna Mignot,[a, b, e] Charles Truillet,[a] Fran�ois Lux or sensitising for radiotherapy.[1­5] Nanoparticles for theranostic applications need to be bio- compatible

493

Binding Specificity of Amino Acids to Amorphous Silica Surfaces: Solid-State NMR of Glycine on SBA-15  

Science Journals Connector (OSTI)

Herein, [1-13C,15N]glycine interactions with amorphous silica surface of SBA-15 were comprehensively characterized using multinuclear, solid-state NMR techniques (REDOR, TEDOR, SLF, 2D-HETCOR). ...

Ira Ben Shir; Shifi Kababya; Asher Schmidt

2012-04-12T23:59:59.000Z

494

Evaluation of Laser-Induced Breakdown Spectroscopy (LIBS) for Measurement of Silica on Filter Samples of Coal Dust  

Science Journals Connector (OSTI)

Airborne silica dust (quartz) is common in coal mines and represents a respiratory hazard that can lead to silicosis, a potentially fatal lung disease. With an eye toward developing a...

Stipe, Christopher B; Miller, Arthur L; Brown, Jonathan; Guevara, Edward; Cauda, Emanuele

2012-01-01T23:59:59.000Z

495

Mechanical relaxation behavior of polyurethanes reinforced with the in situ-generated sodium silica-polyphosphate nanophase  

E-Print Network [OSTI]

Further exploration of hybrid organic/inorganic composites (polyurethane based with inorganic material sodium silica polyphosphate) properties with mechanical relaxometer gives ability to analyze microstructure of such materials in terms of chain reptation tubes filler's fractal aggregates and stress amplification.

V. O. Dupanov; S. M. Ponomarenko

2014-10-31T23:59:59.000Z

496

Fabrication of ultrafine carbon fibers possessing a nanoporous structure from electrospun polyvinyl alcohol fibers containing silica nanoparticles  

Science Journals Connector (OSTI)

Ultrafine carbon fibers with a nanoporous structure were fabricated by the template method using silica nanoparticles (NPs) embedded in fibers of approximate diameter 500 nm, electrospun from an aqueous solution of polyvinyl alcohol, CoCl2, ...

Koichi Sawada, Shinji Sakai, Masahito Taya

2014-01-01T23:59:59.000Z

497

Categorical Exclusion Determinations: Delaware | Department of Energy  

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

Delaware Delaware Categorical Exclusion Determinations: Delaware Location Categorical Exclusion Determinations issued for actions in Delaware. DOCUMENTS AVAILABLE FOR DOWNLOAD August 12, 2013 CX-011107: Categorical Exclusion Determination High Efficiency Thin Film Fe2SiS4 and Fe2GeS4-based Cells Prepared from Low-Cost Solution CX(s) Applied: B3.6 Date: 08/12/2013 Location(s): Delaware Offices(s): Golden Field Office September 18, 2012 CX-010528: Categorical Exclusion Determination Durability Investigation for Quarternary Phosphonium-based Polymer Hydroxide Exchange Membranes CX(s) Applied: B3.6 Date: 09/18/2012 Location(s): Delaware Offices(s): Advanced Research Projects Agency-Energy September 6, 2012 CX-009147: Categorical Exclusion Determination Delaware State Energy Program Formula Grant Application

498

Infrared spectroscopic studies of carbon monoxide adsorbed on a series of silica-supported copper catalysts in different oxidation states  

SciTech Connect (OSTI)

Infrared spectroscopy has been used to study the adsorption of carbon monoxide (358-493 K, 0.1-20 kPa) on four copper-on-silica (2-10 wt% Cu) catalysts prepared by the ion-exchange technique. The measurements are made for each sample in three different states: unreduced (predominantly Cu{sup 2+}), and reduced (Cu{sup 0}), and partially reoxidized in nitrous oxide (Cu{sup +}). On unreduced samples, a major absorption band between 2127 and 2132 cm{sup {minus}1} due to CO adsorbed on small CuO particles and a weak band at 2199 cm{sup {minus}1} due to CO on isolated Cu{sup 2+} ions incorporated in the silica surface have been identified. The former adsorption obeys a Langmuir isotherm with a heat of adsorption of 29 kJ/mol independent of CuO particle size and surface coverage. After catalyst reduction, the major absorption band lies between 2090 and 2113 cm{sup {minus}1} and arises from CO linearly bound to very small (1- to 5-nm) copper metal clusters. The observed frequency shifts indicate the presence of steps and terraces similar to low index Cu planes in very small particles (1- to 2-nm), and the presence of similar higher index Cu planes on larger clusters (2- to 5-nm). The absorption is described by a Freundlich isotherm with the heat of CO adsorption decreasing with coverage from 50 to 22 kJ/mol on bigger particles but more constant (27 to 22 kJ/mol) on small particles. A surface copper/CO atomic ratio increasing from 5 to 12 is established at equilibrium saturation between 358 and 493 K using extinction coefficients determined in this study. In the reduced catalysts, a weakly adsorbed ({Delta}H{sub a} = {minus}20 kJ/mol) species assigned to CO bound to isolated Cu{sup +} ions is also found and absorbs at 2175 cm{sup {minus}1}. The frequency of this band does not vary with catalyst loading and is not affected by reoxidation of the catalyst in nitrous oxide.

Kohler, M.A.; Wainwright, M.S.; Trimm, D.L.; Cant, N.W. (Macquarie Univ., New South Wales (Australia) Univ. of South Wales (Australia))

1989-05-01T23:59:59.000Z

499

Effect of rogue particles on the sub-surface damage of fused silica during grinding/polishing  

SciTech Connect (OSTI)

The distribution and characteristics of surface cracks (i.e., sub-surface damage or scratching) on fused silica formed during grinding/polishing resulting from the addition of rogue particles in the base slurry has been investigated. Fused silica samples (10 cm diameter x 1 cm thick) were: (1) ground by loose abrasive grinding (alumina particles 9-30 {micro}m) on a glass lap with the addition of larger alumina particles at various concentrations with mean sizes ranging from 15-30 {micro}m, or (2) polished (using 0.5 {micro}m cerium oxide slurry) on various laps (polyurethanes pads or pitch) with the addition of larger rogue particles (diamond (4-45 {micro}m), pitch, dust, or dried Ceria slurry agglomerates) at various concentrations. For the resulting ground samples, the crack distributions of the as-prepared surfaces were determined using a polished taper technique. The crack depth was observed to: (1) increase at small concentrations (>10{sup -4} fraction) of rogue particles; and (2) increase with rogue particle concentration to crack depths consistent with that observed when grinding with particles the size of the rogue particles alone. For the polished samples, which were subsequently etched in HF:NH{sub 4}F to expose the surface damage, the resulting scratch properties (type, number density, width, and length) were characterized. The number density of scratches increased exponentially with the size of the rogue diamond at a fixed rogue diamond concentration suggesting that larger particles are more likely to lead to scratching. The length of the scratch was found to increase with rogue particle size, increase with lap viscosity, and decrease with applied load. At high diamond concentrations, the type of scratch transitioned from brittle to ductile and the length of the scratches dramatically increased and extended to the edge of the optic. The observed trends can explained semi-quantitatively in terms of the time needed for a rogue particle to penetrate into a viscoelastic lap. The results of this study provide useful insights and 'rules-of-thumb' relating scratch characteristics observed on surfaces during optical glass fabrication to the characteristics rogue particles causing them and their possible source.

Suratwala, T I; Steele, R; Feit, M D; Wong, L; Miller, P E; Menapace, J A; Davis, P J

2007-05-02T23:59:59.000Z

500

The role of effective stress on silica solubility and pressure solution: an experimental investigation in a flow-through system  

E-Print Network [OSTI]

THE ROLE OF EFFECTIVE STRESS ON SILICA SOLUBILITY AND PRESSURE SOLUTION: AN EXPERIMENTAL INVESTIGATION IN A FLOW-THROUGH SYSTEM A Thesis by BRIAN PATRICK ELIAS Submitted to the Office of Graduate Studies of Texas A&M University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1989 Major Subject: Geology THE ROLE OF EFFECTIVE STRESS ON SILICA SOLUBILITY AND PRES SURE SOLUTION: AN EXPERIMENTAL INVESTIGATION IN A FLOW-THROUGH SYSTEM A Thesis by BRIAN...

Elias, Brian Patrick

2012-06-07T23:59:59.000Z