WorldWideScience
1

The Effects of Surface Chemistry on the Properties of Proteins Confined in Nano-porous Materials  

Energy Technology Data Exchange (ETDEWEB)

The entrapment of proteins using the sol-gel route provides a means to retain its native properties and artificially reproduce the molecular crowding and confinement experienced by proteins in the cell allowing investigation of the physico-chemical and structural properties of biomolecules at the biotic/abiotic interface. The biomolecules are spatially separated and 'caged' in the gel structure but solutes can freely permeate the matrix. Thus, properties such as the folding of ensembles of individual molecules can be examined in the absence of aggregation effects that can occur in solution studies. Green fluorescent protein from Aequorea coerulescens was used as a model protein to examine the unfolding/re-folding properties of protein in silica gels. The recombinant protein was isolated and purified from Escherichia coli extracts by cell lysis, three-phase partitioning, dialysis, and ...

2007-09-01

2

Amorphous cellulose gel as a fat substitute in fermented sausages  

British Library Electronic Table of Contents (United Kingdom)

Fermented sausages were produced with 25%, 50%, 75% or 100% of their pork back fat content replaced by amorphous cellulose gel. The sausage production was monitored with physical, chemical and microbiological analyses. The final products were submitted to a consumer study, and the volatile compounds of the final products were extracted by solid-phase microextraction and analyzed by GC/MS. The reformulated fermented sausages had significant reductions in fat and cholesterol, and the volatile compounds derived from lipid oxidation were also reduced in the final products. These results suggest that the substitution of up to 50% of the pork back fat content by amorphous cellulose gel can be accomplished without a loss of product quality, enabling the production of fermented sausages with the l...

2012-01-01

3

Vibrational spectroscopy of silica sol-gel components during microwave irradiation  

Energy Technology Data Exchange (ETDEWEB)

In order to study the effects of microwaves on chemical reactions equipment was designed to acquire in-situ vibrational spectra of sol-gel components as they are irradiated with microwaves. Fourier Transform Infrared (FTIR) and Raman spectroscopy were used. A low temperature (10K) FTIR cell was used to trap samples in an argon matrix at 10{sup -7} Torr. For the liquid samples no differences were seen in spectra of irradiated and nonirradiated samples, but the argon matrix isolation technique showed dramatic differences.

1995-12-31

4

Synthesis of nanocrystalline YSZ (ZrO_2-8Y_2O_3) powder by polymerized complex method  

International Nuclear Information System (INIS)

In this study nanocrystalline powders of yttria-stabilized zirconia (ZrO_2-8Y_2O_3) have been synthesized through 'polymerized complex method'. Zirconium chloride, yttrium nitrate, citric acid and ethylene glycol were polymerized at 80 "oC to produce a gel-like mass in which metallic ions were uniformly distributed. During the thermal treatment of dried gel, nanocrystalline powder was formed at 450 "oC and 650 "oC for 2 h. Thermal reactions and crystalline phase formation of the dried gel were investigated through thermal analysis and X-ray diffraction analysis, respectively. The results of thermal analysis and XRD showed the formation of nanocrystalline powder at less than 600 "oC. Chemical bonding of the dried gel was investigated by Fourier transform infrared spectroscopy analysis. Morphology of powder calcined at 650 "oC was analyzed by scanning electron microscope. ...

2010-02-18

5

Silylation of low-density silica and bridged polysilsesquioxane aerogels  

Energy Technology Data Exchange (ETDEWEB)

Silica and bridged polysilsesquioxane aerogels are low-density materials that are attractive for applications such as thermal insulation, porous separation media or catalyst supports, adsorbents, and cometary dust capture agents. However, aerogels are notoriously weak and brittle making it difficult to handle and machine monoliths into desired forms. This complication prevents the development of many applications that would otherwise benefit from the use of the low-density materials. Here, we will describe our efforts to chemically modify and mechanically enhance silica-based aerogels using chemical vapor techniques without sacrificing their characteristic low densities. Monolithic silica and organic-bridged polysilsesquioxane aerogels were prepared by sol-gel polymerization of the respective methoxysilane monomers followed by supercritical carbon dioxide drying of the gels. Then the ...

2004-01-01

6

Influence of lanthanum (x) concentration on the properties of x/65/35 PLZT electroceramics  

International Nuclear Information System (INIS)

Lead lanthanum zirconate titanate (PLZT) nanopowders with chemical compositions x/65/35 PLZT (x = 6 - 10 mol%) were prepared by sol-gel method. PLZT ceramics was obtained by the conventional sintering method and utilizing the hot pressing method. The investigations of dielectric and ferroelectric measurements of as obtained PLZT ceramics have revealed the influence of lanthanum concentration on the properties of PLZT electroceramics. (author)

2003-09-25

7

Results of laboratory studies to investigate new gel-forming composites for temporary capping of beds  

Energy Technology Data Exchange (ETDEWEB)

Formulas were developed based on an aqueous solution of hydrolyzed polyacrylonitrile widely used in the oil industry. The additive used consisted of products of industrial production: synthetic resin TEG-1 with hardening agent PEPA (polyehtylene polyamine) and technical formalin. The mixtures containing about 80-85% by volume 5% hydrolyzed polyacrylonitrile, 10-15% by volume of resin TEG-1 with hardening agent PEPA and 3-5% by volume formalin satisfy the requirements made for the plugging materials. The initial mixtures are distinguished by technological efficiency of preparation and have controllable hardening periods. Physical-chemical properties are given for the gel polymers. In the set of properties, the mixtures based on hydrolyzed polyacrylonitrile, resin TEG-1 with hardening agent PEPA and formalin can be recommended as plugging materials of temporary action with complex treatment of the heterogeneous beds.

1982-01-01

8

Sol-gel coatings with phosphonate functionalities for surface modification of magnesium alloys  

International Nuclear Information System (INIS)

Hybrid organic-inorganic coatings with phosphonate functionalities have been synthesized and evaluated as prospective surface treatments for magnesium materials. These coatings have been processed via a sol-gel route by hydrolysis and condensation of a mixture of diethylphosphonatoethyltriethoxy-silane and tetraethoxy-silane with variable molar ratios. The coatings morphology and the surface chemistry at the coating/substrate interface have been characterized using scanning electron microscopy, X-ray photoelectron spectroscopy, "3"1P nuclear magnetic resonance spectroscopy, and time-of-flight secondary ion mass spectrometry. The corrosion protection performance of the coatings deposited on magnesium alloy AZ31B has been examined by a group of electrochemical techniques including potentiodynamic polarization and electrochemical impedance spectroscopy. In addition, a scanning Kelvin probe technique has been used to investigate interfacial properties of the coatings. ...

2006-08-30

9

Effect of additives in the positive active mass of lead batteries. Zur Wirkung von Zusaetzen in der positiven Aktivmasse des Bleiakkumulators  

Energy Technology Data Exchange (ETDEWEB)

In order to improve the capacity and service life of cathodes, the effect of carboxy-methyl cellulose, soot, silica gel and fibres was examined. Structural tests and electrical and electro-chemical measurements are used for this. The additives can affect crystallization in the manufacturing stage of the electrodes and can increase the storage capacity for water and the electronic conductivity. They act to stabilize the mass in cyclic operation. Soot additive has little effect on the properties of the electrode, but the other substances increase the service life or the use of the mass. (LU).

1984-01-01

10

Multiscale Mechanical Characterization of Biomimetic Gels for ...  

Science.gov (United States)

... MECHANICAL PROPERTIES, *COPOLYMERS, *SOFT TISSUES, *GELS, *BIOMIMETICS, ISOPRENE, WOUND BALLISTICS, STYRENE PLASTICS ...

2006-11-01

11

Surface coating on carbon nanofibers with alumina precursor by different synthesis routes  

British Library Electronic Table of Contents (United Kingdom)

Alumina-reinforced carbon nanofiber nanocomposites were prepared using different routes; powders mixture, colloidal route and sol?gel process followed by spark plasma sintering (SPS). CNFs/xAl2O3 (x = 10?50 vol.%) were prepared through nanopowders mixing in a high-energy attrition milling. The main limitations in the preparation of this kind of nanocomposites are related to the difficulty in obtaining materials with a homogeneous distribution of both phases and the different chemical nature of CNFs and Al2O3, which causes poor interaction between them. A surface coating of CNFs by wet chemical routes with an alumina precursor is proposed as a very effective way to improve the interaction between CNFs and Al2O3. An improvement of 50% in fracture strength was found for similar nanocomposite ...

2011-01-01

12

Preliminary studies on the chemical characterization and antioxidant properties of acidic polysaccharides from Sargassum fusiforme  

British Library Electronic Table of Contents (United Kingdom)

In order to investigate the antioxidant properties of the polysaccharides from the brown alga Sargassum fusiforme, the crude polysaccharides from S. fusiforme (SFPS) were extracted in hot water, and the lipid peroxidation inhibition assay exhibited that SFPS possessed a potential antioxidant activity. Hence, two purely polymeric fractions, SFPS-1 and SFPS-2 were isolated by the column of DEAE (2-diethylaminoethanol)-Sepharose Fast Flow, with their molecular weights of 51.4 and 30.3 kDa determined by high performance gel permeation chromatography (HPGPC). They were preliminarily characterized using chemical analysis in combination of infrared (IR) and nuclear magnetic resonance (NMR) spectroscopies and found to contain large amounts of uronic acids and ?-glycosidical linkages. The antioxida...

2008-01-01

13

Disulfide Bonds and the Quaternary Structure of Factor VIII/von Willebrand Factor  

UK PubMed Central (United Kingdom)

Human Factor VIII/von Willebrand factor, purified by calcium citrate-cellulose chromatography and 4% agarose gel filtration was subjected to sodium dodecyl sulfate gel electrophoresis on gels containing...Full Text Available

1978-09-01

14

Dihydroxybenzene/benzoquinone-containing polymers: organic redox polymers  

Energy Technology Data Exchange (ETDEWEB)

Polymers containing hydroquinone, catechol or their corresponding benzoquinones are a special class of redox polymers. Three pathways of their syntheses are possible: condensation polymerization of suitable monomers, addition polymerization of vinyl monomers containing redox moiety, and chemical attachment of redox unit onto pre-made polymeric matrix. A range of functionalized matrices have been employed such as polyethers, polyesters, polycarbonates, polyurethanes, polyamides and others. Protection of their phenolic functionality has conducted to chemically interesting redox polymer precursors. The presence of a redox moiety coupled with the extant functionalization of the polymer matrix makes the materials very valuable, of wide properties and consequently of vast applicability. For instance, in the oil field, some polymers such as carboxy-methyl-cellulose (CMC) are often applied as to bring about a viscosity improvement and therefore to ...

2000-08-01

15

Synthesis of metallic nanoparticles in SiO{sub 2} matrices; Sintesis de nanoparticulas metalicas en matrices de SiO{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

Metallic nanoparticles was synthesized in SiO{sub 2} matrices by means of a process of two stages. The first one proceeded via sol-gel, incorporating the metallic precursors to the reaction system before the solidification of the matrix. Later on, the samples underwent a thermal treatment in atmosphere of H{sub 2}, carrying out the reduction of the metals that finally formed to the nanoparticles. Then it was detected the presence of smaller nanoparticles than 20 nm, dispersed and with the property of being liberated easily of the matrix, conserving a free surface, chemically reactive and with response to external electromagnetic radiation. The system SiO{sub 2}-Pd showed an important thermoluminescent response. (Author)

2004-07-01

16

Ru/SiO2 AND CuRu/SiO2 PREPARED BY SOL-GEL: EFFECT OF pH AND WATER AMOUNT  

Scientific Electronic Library Online (English)

Abstract in english Ru(1%)/SiO2 and Cu(1%)Ru(1%)/SiO2 catalysts were prepared by cogelation. The effect of pH and the amount of water on the physical-chemical properties and the catalytic properties of them were analyzed. The acid medium increased the formation of microporosity and the formation of small size of metallic ruthenium particle. The variation of the water quantity used in the gelation not modify considerably the texture neither the dispersion of the noble metal. The reduction lev (more) el of all prepared catalyst was similar, showing displacement in some of reduction peaks. The toluene hydrogenation indicated that the conversion and the quantity of hydrogenate product varied with the pH and the quantity of water used in the gelation. The addition of copper to Ru/SiO2 catalysts diminished the reactive conversion and their hydrogenant activity

2003-06-01

17

Length-sorted semiconducting carbon nanotubes for high-mobility thin film transistors  

British Library Electronic Table of Contents (United Kingdom)

We have developed a process for chemical purification of carbon nanotubes for solution-processable thin-film transistors (TFTs) having high mobility. Films of the purified carbon nanotubes fabricated by simple drop coating showed carrier mobilities as high as 164 cm2V?1s?1, normalized transconductances of 0.78 Sm?1, and on/off current ratios of 106. Such high performance requires the preparation of a suspension of micrometer-long and highly purified semiconducting single-walled carbon nanotubes (SWCNTs). Our purification process includes length and electronic-type selective trapping of SWCNTs using recycling gel filtration with a mixture of surfactants. The results provide an important milestone toward printed high-speed and large-area electronics with roll-to-roll and ink-jet device fabri...

2011-01-01

18

Hydrotalcities as base catalysts: Influence of the chemical composition and synthesis conditions on the dehydrogenation of isopropanol  

Science.gov (United States)

Hydrotalcites with different Al/Al+Mg ratios, and prepared at different pH and different aging temperatures of the gel were used as precursors of Mg-Al mixed oxides, and their textural and physicochemical properties were determined. A complete reaction network for the isopropanol decomposition on these catalysts has been established, and it is shown that the concentration of acetone in the products cannot always be used for a direct estimation of the rate of dehydrogenation. The Al/Al+Mg ratio for which the maximum in activity is obtained depends on the base strength needed for each particular reaction. For dehydrogenation of isopropanol, this is found at Al/Al+Mg [approx] 0.25. 36 refs., 10 figs., 2 tabs.

1994-07-01

19

Chain radiation-chemical cross-linking of polyethylene under high pressures. [Gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

Regularities in the radiation cross-linking of low-density polyethylene under various conditions of ..gamma..-irradiation were studied. It is shown that at the 0.5 GPa pressure and 450 K the gel formation is initiated at doses of about 1 kGy, i.e. at doses 10 times as low as compared to normal conditions. Abnormally high rate of radiation cross-linking at high temperature and high pressure is an evidence of changes in the mechanism of polyethylene, radiation cross-linking, i.e. of the process transition from nonchain to chain conditions. Decrease in the potential barriers of macroradical reactions with macromolecules is the most probable reason of change in the polymer cross-linking nature.

1984-01-01

20

A Comparative Study of Pectin Extracted from Passion Fruit Rind Flours  

British Library Electronic Table of Contents (United Kingdom)

Brazil is the world?s main producer of passion fruit. Previous reports show that passion fruit rinds, an industrial waste, contain large amounts of pectin. Pectin is a dietary fiber that is widely used in the food industry as a gelling agent and stabilizer. In this study, the quality and characteristics of pectin extracted from yellow passion fruit rind flour was investigated. Pectin was extracted from both commercially available and prepared passion fruit peels using nitric acid. Once extracted, the pectin was evaluated for its molecular characteristics and chemical composition as well as for the apparent and reduced viscosity of the gel. Prepared (blanched) rind flour yielded 203.4?g?kg?1 of pectin, which contained a uronic acid content of 681?mg?g?1, a degree of esterification of 80, a ...

2010-01-01

23

Sealants for sources emanating Rn-222  

International Nuclear Information System (INIS)

(Oct 1974). United Kingdom Bedrosian, PH Sensintaffar, EL Gels, GL

25

Preparation and characterization of CdS nanoparticles and CdS/polyacrylonitrile nanocomposites by {gamma}-irradiation  

Energy Technology Data Exchange (ETDEWEB)

There has been considerable interest in producing and studying nanoparticle materials because of the effect of size on their structure, physical and chemical structure. Most studied nanoparticle semiconductors belong to the II-VI group, as they are relatively easy to synthesize and are generally prepared as particulates or in thin film form. Among II-VI compounds, CdS is one of the most studied materials. There are different ways to synthesize CdS nanoparticles such as colloidal particles, chemical decomposition, sol-gel, gas evaporation, magnetron sputtering, electrostatic deposition, and etc. {gamma}-irradiation is one of the effective methods for synthesis of nanomaterials. These nonomaterials have been extensively used in the preparation of nanocrystalline metals, metal oxides, and metal-polymer composites. However, The preparation of CdS nanoparticle and CdS/ polyacrylonitrile nanocomposite by {gamma}-irradiation ...

2001-11-15

26

Sol-gel approaches for solid electrolytes and electrode materials. Technical report  

Energy Technology Data Exchange (ETDEWEB)

Sol-gel chemistry has a great many potential applications in the preparation of unique electrochemical materials, from non-equilibrium transition metal oxides which may be of use as high energy density electrodes, to high-surface area mixed oxides which may possess high proton conductivity, to novel composite structures consisting of inorganic gels in combination with organic, electronic, and ionic conductors. This paper reviews prior work on proton conduction in gel systems and presents recent work regarding electrode materials prepared by sol-gel methods and inorganic-organic materials.

1995-07-14

27

Ovariectomy-induced changes in aged beagles : histomorphometry of rib cortical bone.  

Energy Technology Data Exchange (ETDEWEB)

Bone loss associated with estrogen depletion is well documented in cancellous bone but less well characterized in cortical bone. The effects of ovariectomy on the aged beagle skeleton were studied by histomorphometric analysis of the cortical bone in sequential rib biopsies. Biopsies were taken from each ovariectomized or sham-operated dog at the time of surgery and at 1, 4, and 8.5 months after surgery. Just prior to each postoperative biopsy, tetracycline, calcein, and xylenol orange, respectively, were administered by a fluorochrome labeling procedure (2d-10d-2d) to provide markers of bone formation. Analysis of sequential rib biopsies provided a means to follow the ovariectomy response over time and to compare each animal against its own baseline. Though ovariectomy did not influence histomorphometric indices at 1 month after surgery, a transient increase in cortical bone formation occurred thereafter, with a sixfold increase over that of sham-operated dogs at ...

1998-03-01

28

Effect of irradiation on bone remodelling and the structural integrity of the vertebral column. Doctoral thesis  

Energy Technology Data Exchange (ETDEWEB)

The effects of therapeutic levels of radiation on the axial properties of the primate vertebral column were studied. Seven male rhesus monkeys (Macaca mulatta) were irradiated with a single does of 1300 cGy to the specific lumbar vertebrae of L2, L3, and L4. Three additional animals served as controls. Radiographs were taken before the radiation treatment and just prior to sacrifice to determine density changes in the bone. The animal subjects were sacrificed 105 days following the radiation exposure. Biomechanical testing was completed on lumbar levels 2 and 3 to identify changes in strength characteristics following radiation treatment. Histomorphometric analysis of lumbar vertebrae level 4 was completed to identify volume and surface density changes as well as cellular changes. Tetracycline, dicarbomethylaminomethyl fluorescein (DCAF), and xylenol orange were used as bone labeling agents to aid in the histomorphometry and to obtain dynamic parameter changes.

1990-01-01

29

Optical chemical sensors for atmospheric pollutants based on nano porous materials: application to the formaldehyde and the other carbonyl compounds; Capteurs chimiques a transduction optique de polluants atmospheriques a base de materiaux nanoporeux: application au formaldehyde et autres composes carbonyles  

Energy Technology Data Exchange (ETDEWEB)

Formaldehyde, a well-identified indoor pollutant, was recently classified as carcinogenic. New regulations for the air quality are expected and therefore there is a need for low-cost sensors, sensitive and selective with a fast response time for the detection of formaldehyde at ppb level. In the present work, we had developed a chemical sensor based on nano-porous matrices doped with Fluoral-P and optical methods of detection. The nano-porous matrices, elaborated via the Sol-Gel process, display nano-pores whose cavity is tailored for the trapping of the targeted pollutant. They provide a first selectivity with the discrimination of the pollutants by their size. A second selectivity is obtained with a molecular probe, Fluoral-P, which reacts specifically with formaldehyde leading to the 3,5- di-acetyl-1,4-dihydro-lutidine (DDL). The kinetics of formation of DDL was studied as function of many parameters such as the concentration of Fluoral-P in ...

2006-12-15

30

Investigation of Symphytum cordatum alkaloids by liquid-liquid partitioning, thin-layer chromatography and liquid chromatography-ion-trap mass spectrometry  

Energy Technology Data Exchange (ETDEWEB)

From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ionization (APCI) interface ...

2006-05-04

31

Enhanced corrosion resistance by sol-gel-based ZrO_2-CeO_2 coatings on magnesium alloys  

International Nuclear Information System (INIS)

The physical, chemical and mechanical properties of magnesium alloys make them attractive materials for automotive and aerospace applications. However, these materials are susceptible to corrosion and wear. This work discusses the potential of using sol-gel based coatings consisting of ZrO_2 and 15 wt.% of CeO_2. The CeO_2 component provides enhanced corrosion protection, while ZrO_2 impart corrosion as well as wear resistance. Coating deposition was performed by the dip coating technique on two magnesium alloy substrates with different surface finishes: AZ91D (as-casted, sand-blasted, and machined) and AZ31 (rolled and machined). All as-deposited coatings (xerogel coatings) were then subjected to 10 h annealing: a temperature of 180 C was applied to the AZ91D alloy and 140 C to the AZ31 alloy. Morphological and structural properties of the annealed coatings were investigated by scanning electron microscopy, atomic force microscopy and ...

2005-02-01

32

Distribution of lead-203 in human peripheral blood in vitro  

International Nuclear Information System (INIS)

In-vitro experiments using "2"0"3Pb were performed to identify the lead binding components in human peripheral blood. The distribution of lead in plasma, in the red cell membrane, and within the red cell was also investigated. Studies of the distribution of "2"0"3Pb in the whole blood showed that at a lead concentration of 2.45 #mu#mol/l (50 #mu#g/100 ml) about 94% of lead had been incorporated by the erythrocytes and 6% remained in the plasma. After extraction of lipid by a methanol/chloroform mixture, about 75% of the lead was found to be associated with the protein fraction. The lipid contained about 21% of the "2"0"3Pb, the remainder being in the aqueous plasma. SDS polyacrylamide gel electrophoresis of blood plasma showed that almost 90% of the "2"0"3Pb was present in the albumin fraction; the remainder was likely to be associated with high molecular weight globulins. Several binding sites were identified on the erythrocyte membrane. The high molecular weight ...

33

Activation analysis of trace elements in titanium-molybdate target used for pre-formed TiMo gel based "9"9"mTc generator production and radionuclidic impurity of "9"9"mTc pertechnetate eluate  

International Nuclear Information System (INIS)

A gel-type "9"9Mo-"9"9"mTc generator using Titanium-Molybdate target (TiMo-target) as column packing was developed in Radioisotope Department, the Dalat Nuclear Research Institute [1]. The concentration of trace elements in TiMo-target and radionuclidic purity in "9"9"mTc solution eluted from this type of generator were studied for quality control purpose. The monostandard method in neutron activation analysis has been applied to determine the concentration of trace impurities in titanium-molybdate target. For neutron activation analysis, TiMo samples were irradiated in the different channels of nuclear reactor IVV-9 at a neutron flux of maximum 2.1 x 10"1"3 n.cm"-"2s"-"1. The following chemical element impurities were determined: Na, W, Co, Fe, Zn, Ag, Sb and Cr. The gamma ray emitted nuclides found in "9"9"mTc solution eluted from our "9"9"mTc generator were the following: "6"5Zn, "6"0Co, "1"1"0"mAg, "5"9Fe, "5"1Cr, "2"4Na, "8"2Br and "9"9Mo. ...

2004-06-01

34

Achievement report for fiscal 1998. Research and development on a new manufacturing method for functional thin films suitable for recycling, and their application to colored glasses (the second year); 1998 nendo seika hokokusho. Recycle ni tekishita kinosei usumaku no shinki seizoho to chakushoku glass eno oyo ni kansuru kenkyu kaihatsu (dai 2 nendo)  

Energy Technology Data Exchange (ETDEWEB)

A new thin film manufacturing method is established to add a function to glass material surface, as a new material technology which harmonizes with global environment, and is suitable for resource re-utilization and energy conservation. It is intended to develop a leading technology to promote recycling of colored glasses by applying this technical method to colored glasses. Fiscal 1998 has implemented subsequently to fiscal 1997 the following subjects in the three research items composed of a new manufacturing method of functional thin films, application of the functional thin films to colored glasses, and the comprehensive investigative studies: establishment of an industrial manufacturing method for color coating liquid and evaluation of basic characteristics of the colored functional thin films, optimization of element technology for photo-sensitive gel films by means of chemically modifying metallic alkoxide, tests of forming films on ...

1999-03-01

35

Size-dependent surface plasmon resonance in silver silica nanocomposites  

Energy Technology Data Exchange (ETDEWEB)

Silver silica nanocomposites were obtained by the sol-gel technique using tetraethyl orthosilicate (TEOS) and silver nitrate (AgNO{sub 3}) as precursors. The silver nitrate concentration was varied for obtaining composites with different nanoparticle sizes. The structural and microstructural properties were determined by x-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). X-ray photoelectron spectroscopic (XPS) studies were done for determining the chemical states of silver in the silica matrix. For the lowest AgNO{sub 3} concentration, monodispersed and spherical Ag crystallites, with an average diameter of 5 nm, were obtained. Grain growth and an increase in size distribution was observed for higher concentrations. The occurrence of surface plasmon resonance (SPR) bands and their evolution in the size range 5-10 nm is studied. For decreasing nanoparticle size, a redshift and ...

2008-02-20

36

Improvement of leaching characteristics of TOC from condensate demineralizers  

International Nuclear Information System (INIS)

Recent nuclear power plants require high purity water to protect nuclear reactors or steam generators from SCC and maintain in good condition. In this connection, it is especially important to minimize sulfate, which is a corrosive chemical originated from oxidative degradation of cation exchange resins during operation. Recently, uniform particle size (UPS) strong acid cation gel resin with 14% cross-linkage, which has excellent stability against oxidization, has been applied to several condensate purification systems. For further improvement of water quality, some methods for changing the configuration of condensate demineralizer's resin bed have been examined. For example, these methods correspond to anion under layer and cation over layer. We have tested these methods by cold column tests. Furthermore, we have developed the newly anion exchange resin having higher efficiency and capacity for absorbing leachables from cation exchange resins. ...

2009-10-01

37

Evaluation of heavy-metal ion toxicity in fish cells using a combined stress protein and cytotoxicity assay  

Energy Technology Data Exchange (ETDEWEB)

All organisms, from bacteria and yeast to humans, respond to physical and chemical stressors by increasing the synthesis of a small group of cellular stress proteins.'' The authors have developed a simple in vitro system for quickly screening environmentally relevant stressors to detect stress-induced proteins that are good candidates for biomarkers. Polyacrylamide gel electrophoresis was used to detect stressor-induced, concentration-dependent changes in cellular stress protein levels in two fish cell culture systems, whereas simultaneous in vitro neutral red uptake cytotoxicity assays measured the stressors effect on cellular physiology. There was a direct concentration-dependent relationship between sublethal cytotoxic effects and the increases in stress protein levels. Increases of 50 to 200% were detected in stress proteins from desert topminnow, Poeciliopsis lucida, hepatoma-derived cell cultures exposed to cadmium or ...

1994-08-01

38

Chemical synthesis and characterization of Ca-substituted YAlO_3 as electrolyte for solid oxide fuel cells  

International Nuclear Information System (INIS)

In this study, perovskite type oxide YAlO_3 has been doped with different amounts of the divalent cation Ca to synthesize Y_1_-_xCa_xAlO_3_-_#delta# (x = 0-0.21) compositions. The effect of dopant concentration on the crystal structure and electrical properties of YAlO_3 synthesized by citrate gel route has been investigated. The phase purity of the samples has been carried out using X-ray diffraction. The microstructural evaluation of the samples has been conducted by scanning electron microscopy and energy dispersive spectrum analysis. Thermal analysis has been conducted to monitor the decomposition of the intermediate products. The electrical conductivity studies have been performed using a.c. impedance spectroscopy as a function of temperature in the range 200-800 "oC in air. The Y_0_._9_4Ca_0_._0_6AlO_3_-_#delta# composition exhibits a total conductivity of 2.5 mS/cm at 800 "oC.

2010-04-30

39

ProMoST: A tool for calculating the pI and molecular mass of phosphorylated and modified proteins on 2 dimensional gels  

UK PubMed Central (United Kingdom)

Protein modifications such as phosphorylation are often studied by two-dimensional gel electrophoresis since the perturbation in the protein’s pI value is readily detected by this method....Full Text Available

2009-01-01

40

Computer simulation of protein self-association during small-zone gel filtration. Estimation of equilibrium constants.  

UK PubMed Central (United Kingdom)

A simulation is developed that qualitatively describes the small-zone-gel-filtration behaviour of a reversibly associating protein. The results reflect the dependence of the apparent molecular weight...Full Text Available

1981-04-01

41

An evaluation of cerebrospinal fluid oligoclonal banding confirmed by immunofixation on agarose gel.  

UK PubMed Central (United Kingdom)

The cerebrospinal fluid (CSF) from 115 consecutive patients undergoing diagnostic lumbar puncture or myelography was examined to determine the usefulness of immunofixation, following agarose gel electrophoresis,...Full Text Available

1983-06-01

42

A new method for 2D gel spot alignment: application to the analysis of large sample sets in clinical proteomics  

UK PubMed Central (United Kingdom)

BackgroundIn current comparative proteomics studies, the large number of images generated by 2D gels is currently compared using spot matching algorithms. Unfortunately, differences...Full Text Available

43

A Software System for Data Analysis in Automated DNA?Sequencing  

UK PubMed Central (United Kingdom)

Software for gel image analysis and base-calling in fluorescence-based sequencing consisting of two primary programs, BaseFinder and GelImager, is described. BaseFinder is a framework for trace processing,...Full Text Available

1998-06-01

44
45

One-dimensional free boundary problem for actin-based propulsion of Listeria  

Science.gov (United States)

Some bacteria move inside cells by recruiting the actin filaments of the host cells. The filaments are polymerized at the back surface of the bacteria, and they move away, forming a "comet" tail behind the bacterium, which consists of gel network. We develop a one-dimensional mathematical model of the gel based on partial differential equations which involve the number of filaments, the density and velocity of the gel, and the pressure. The two end-points of the gel form two free boundaries. The resulting free boundary problem is rather non-standard. We prove local existence and uniqueness.

2007-04-01

47

Combustible Water Repellent Coating.  

Science.gov (United States)

... Descriptors : *Combustible cartridge cases, *Water repellents, *Protective coatings, *Patents, Silica gel, Aluminum compounds, Binders ...

1973-07-24

48

Nitrogen doping into titanium dioxide by the sol?gel method using nitric acid  

British Library Electronic Table of Contents (United Kingdom)

N-doped TiO2 has been prepared by use of sol?gel systems containing titanium alkoxide, with nitric acid as the nitrogen source. The time needed for gelation of the systems was drastically reduced by ultrasonic irradiation. The peaks assigned to the nitrate and nitrous ions were observed by FT-IR measurement during the sol?gel reaction. The N-doping was confirmed by the observation of N?O peaks in the XPS spectrum of the sample heated at 400??C. The nitrate ion acted as an oxidizer of the ethanol solvent and titanium species. The TiO2 became doped with nitrogen oxide species as a result of reduction of nitrate ion incorporated into the dried gel samples. These results indicated that the added nitric acid was reduced during the sol?gel transition and heating process, and the resulting NO spe...

2011-01-01

49

Growth of ytterbium tartrate trihydrate crystals in silica and agar-agar gels and their characterization  

British Library Electronic Table of Contents (United Kingdom)

Single crystals of ytterbium tartrate trihydrate have been grown by gel method using silica and agar-agar gels as media of growth. The medium of growth influences the morphology of grown crystals, silica gel yielding single and polycrystalline in the form of spherulites whereas agar-agar gel leading to growth of single and twinned crystals. Materials grown as single crystals have been characterized by using optical and scanning electron microscopy (SEM), EDAX, XRD, FT-IR, CHN and thermogravimetric techniques. The stoichiometry of the grown single crystals is suggested to be Yb(C4H4O6) (C4H5O6).3H2O. The FT-IR spectrum shows the presence of singly as well as doubly ionized tartrate ligands. Results of thermal analysis indicate that the material is thermally stable up to a temperature of 200...

2006-01-01

50

Scatter measurements for optical cone-beam computed tomography  

Energy Technology Data Exchange (ETDEWEB)

Both x-ray and optical cone-beam CT (CBCT) scanners are limited by scattered photons that contaminate the primary images. Transparent radiochromic gels and plastics are anticipated to produce less scattering than polymerization gels and hence result in reconstructed dose distributions with greater contrast and dynamic range. Four methods of scatter measurement were investigated to quantify scatter fractions using an in-house optical CBCT scanner. The methods consisted of generating either 'coin' shadows or primary beamlets in transmission images. The four methods generated similar results of 10% scatter fractions in gel transmission images for this particular scanner configuration with both leuco crystal violet and carbon black micelle gels. The scatter contributions were distributed as 5% from micelle gel, 2% from Teflon wall, 2% from refractive index matching ...

2009-05-01

51

The role of surfactant in synthesis of magnetic nanocrystalline powder of NiFe2O4 by sol-gel auto-combustion method  

British Library Electronic Table of Contents (United Kingdom)

In this work, a new sol-gel auto-combustion method has been performed to synthesize single phase nickel ferrite nanocrystalline powders by using n-cetyltrimethylammonium bromide, as a cationic surfactant. The gels were prepared from ferric and nickel nitrates and citric acid. Ammonia was used as pH adjusting agent as well. The effects of the surfactant on the after combustion calcination process and the reduction of the resulting powder crystallite size which affects the magnetic properties of the material were investigated by XRD and DTA/TGA techniques. The results showed that the ignition of the gels in air have a self-propagating behavior. Addition of surfactant to the starting solution affected the crystallite size of the synthesized powders and their phase constitution. The crystallit...

2008-01-01

52

The actin content of fibroblasts.  

UK PubMed Central (United Kingdom)

Cultures of chick skin fibroblasts were dissolved in solutions of sodium dodecyl sulphate, and their entire protein content was examined by gel electrophoresis. The most abundant species migrated in...Full Text Available

1975-05-01

54

General Disclaimer One or more of the Following Statements may ...  

Science.gov (United States)

Oberpfaffenhofen, Pedel"al aepublic of Gel1lany. A large number of European scientists have provided ex~eri- ments that will be cooducted in the Material ...

55

Effect of alumina incorporation on restricting grain growth of nanocrystalline tin(IV) oxide  

British Library Electronic Table of Contents (United Kingdom)

In this project, nanocrystalline SnO2 powders were successfully prepared by (a) citrate sol-gel and (b) direct precipitation methods. Powders were characterized using thermal analysis techniques (DTA-TG-DSC), X-ray powder Diffraction (XRD), surface area (BET) and electrical conductivity measurements. XRD patterns showed the presence of the cassiterite structure. SnO2 particles, prepared through sol-gel method exhibit crystallite sizes in the range from 3.1 to 22.3 nm when the gel is heat treated at different temperatures up to 900?C. SnO2 nanocrystallites prepared by the precipitation method are comparatively larger in size. The higher specific surface area was obtained for the powder prepared using sol-gel method and the obtained average grain size (d) is relatively large compared with th...

2010-01-01

56

Lithium insertion in V{sub 2}O{sub 5}, M{sub x}V{sub 2}O{sub 5} (M = Fe, Cr, Al, La) mixed oxides; Insertion du lithium dans les oxydes mixtes de V{sub 2}O{sub 5}, M{sub x}V{sub 2}O{sub 5} (M = Fe, Cr, Al, La)  

Energy Technology Data Exchange (ETDEWEB)

V{sub 2}O{sub 5} based compounds are interesting low potential materials for rechargeable cathodes of lithium electrochemical generators. However, the ionic conductivity and the reversibility of electrochemical cycling of V{sub 2}O{sub 5} are limited by the possibilities of lithium insertion. This work shows that the doping of vanadium pentoxide by a M{sup 3+} trivalent transition element (M Fe, Al, Cr or La) allows to intercalate a more important amount of lithium and to improve the behaviour of the material during cycling. These materials of M{sub 0.11}V{sub 2}O{sub 5.16} formula are obtained by sol-gel synthesis. the electrochemical study of the Fe compound has shown that it is a mixed oxide with a behaviour similar to V{sub 2}O{sub 5}. The maximum capacity is of about 2 F/mole in the case of Fe, Al and Cr compounds and of about 1.7 F/mole in the case of La. The structural evolution of the Fe compound has been followed during the chemical ...

1996-12-31

57

LS&T and CMS FY 2004 Feasibility Proposal 04-FS-006 - Ceramic Laser Materials Interim Report - June 8, 2004  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this memo is to give an update on our work on ceramic laser materials--feasibility proposal 04-FS-006. Transparent ceramic materials have several major advantages over single crystals in laser applications including, ease and robustness of manufacturing, large apertures, design flexibility, fracture toughness, high activator concentrations, uniformity of composition, no residual stress, and others discussed in the proposal. After a decade of working on making transparent YAG:Nd in 1995 Japanese workers demonstrated samples for the first time that performed as well in lasers as their single crystal counterparts. Since then several laser materials have been made and evaluated. For these reasons, developing ceramic laser materials is the most exciting and futuristic materials topic in today's major solid-state laser conferences. The highlights and executive summary of our work to date are: (1) Ordered a slab of transparent YAG:Nd from Konoshima ...

2005-02-03

58

Fabrication and dielectric property of ferroelectric PLZT films grown on metal foils.  

Energy Technology Data Exchange (ETDEWEB)

We have grown ferroelectric Pb{sub 0.92}La{sub 0.08}Zr{sub 0.52}Ti{sub 0.48}O{sub 3} (PLZT) films on platinized silicon and LaNiO{sub 3}-buffered nickel substrates by chemical solution deposition using a sol-gel process based on acetic acid chemistry. The following measurements were obtained under zero-bias field: relative permittivity of {approx}960 and dielectric loss of {approx}0.04 on the PLZT film grown on Pt/Si substrates, and relative permittivity of {approx}820 and dielectric loss of {approx}0.06 on the PLZT film grown on LNO-buffered Ni substrates. In addition, a relative permittivity of 125 and dielectric loss of 0.02 were measured at room temperature under a high bias field of 1 x 10{sup 6} V/cm on PLZT deposited on LNO-buffered nickel substrate. Furthermore, a steady-state leakage current density of {approx}8.1 x 10{sup -9} A/cm{sup 2} and mean breakdown field strength of 1.7 x 10{sup 6} V/cm were measured at room temperature. ...

2011-07-01

59

Diagnostic and Therapeutic RI Generators  

Energy Technology Data Exchange (ETDEWEB)

Different types of generators have been developed for the convenient use of {sup 99m}Tc as the demand for this radioisotope is strong. Currently, the demand for {sup 99m}Tc is more than 80 % of the total demand for medical isotopes in the world. A {sup 99m}Tc generator, in general, is composed of a column packed with ceramic adsorbent, tubing, eluent reservoir or vials, collection vials, and shielding. The key technology to develop a good generator is how to load {sup 99}Mo as much as possible while maintaining the quality of eluted {sup 99}mTc as good as possible. The technology is well developed and already available commercially for the case of the fission {sup 99}Mo/{sup 99}mTc because loading of few curries of {sup 99}Mo on a conventional adsorbent, i.e. alumina is not a serious task in the chemical point of view. However, the current infrastructure of the supply of {sup 99}Mo to the world market is sturdy as the research reactors are getting aged. In this ...

2006-07-01

60

PRO2000 vaginal gel for prevention of HIV-1 infection (Microbicides Development Programme 301): a phase 3, randomised, double-blind, parallel-group trial  

UK PubMed Central (United Kingdom)

SummaryBackgroundInnovative prevention strategies for HIV-1 transmission are urgently needed. PRO2000 vaginal gel was efficacious against HIV-1 transmission in studies...Full Text Available

2010-10-16

61

Fractal dimension determination of sol-gel powders using transmission electron microscopy images  

Energy Technology Data Exchange (ETDEWEB)

SiO{sub 2}, TiO{sub 2} and AlO(OH) powders obtained by the sol-gel method were investigated by transmission electron microscopy. The mass-radius relation was used to determine the fractal dimensions from the images. These fractal dimensions were corrected in order to obtain the powder fractal dimensions. The results indicate a good fractal behavior and high fractal dimensions.

2004-09-15

62

Efficacy and tolerability of 0.5% timolol maleate ophthalmic gel-forming solution QD compared with 0.5% levobunolol hydrochloride BID in patients with open-angle glaucoma or ocular hypertension.  

Science.gov (United States)

We compared the efficacy of timolol maleate ophthalmic gel-forming solution 0.5% QD with that of levobunolol hydrochloride 0.5% BID, as measured by change in intraocular pressure (IOP), effect on heart rate, and ocular tolerability. The study had a positive-controlled, double-masked, randomized, multicenter, 12-week, two-period (6 weeks each), crossover design. One hundred fifty-two patients with open-angle glaucoma or ocular hypertension were randomized to receive either timolol maleate gel-forming solution QD or levobunolol BID for 6 weeks, followed by a crossover to the alternate treatment. IOP and heart rate were measured at morning trough and peak during weeks 3, 6, 9, and 12. Timolol maleate gel-forming solution QD was comparable to levobunolol BID in reducing IOP at peak and trough. Although the effects on peak heart rate were similar between the two medications, the effect on trough heart rate of timolol maleate ...

63

Stearic acid gel derived MgTiO{sub 3} nanoparticles: A low temperature intermediate phase of Mg{sub 2}TiO{sub 4}  

Energy Technology Data Exchange (ETDEWEB)

Stearic acid gel is employed to study the phase evolution of MgTiO{sub 3} nanoparticles by thermal gravimetric analysis, X-ray diffraction, and Fourier transform infrared. During the preparation of stearic acid gel, tetrabutyl titanate easily absorbed moisture to hydrolyze into Ti(OH){sub 4} firstly, and then reacts with stearic acid and magnesium stearate to form magnesium-titanium oxide network polymer gel, meanwhile n-butanol is generated. When stearic acid gel is calcined in air, a series of oxidation and combustion reactions occur, meanwhile apparent heat is given off. The results show that a metastable intermediate phase Mg{sub 2}TiO{sub 4} is generated at 450 {sup o}C and nearly disappeared at 550 {sup o}C. Simultaneously, a new solid phase of MgTiO{sub 3} appears. The metastable intermediate phase Mg{sub 2}TiO{sub 4} is successfully identified in the current work.

2010-03-04

64

Removal and recovery system of hexavalent chromium from waste water by tannin gel particles  

Energy Technology Data Exchange (ETDEWEB)

Tannin gel particles that have extremely high adsorption capacity for hexavalent chromium Cr(VI) have been developed by controlling gelation of Mimosa tannin extracted from the bark of plants. The gelation process is composed of two stages; partial gelation of Mimosa tannin by reaction with formaldehyde (cross-linking agent) and granulation by dispersing the partially gelated solution into a liquid mixture of decalin ad a polyether nonionic surfactant with vigorous stirring. The structure of the tannin gel particles is controlled by a combination of operating conditions such as reaction time and temperature at both stages. The water content of the tannin gel particles that reflects their structure can be widely changed from 40 to 79 %(wet basis), even for a constant composition of 23 g Mimosa tannin and 6 ml formaldehyde (37 wt %). It is found that it is very important to increase the water content without losing mechanical ...

2000-10-01

65

Natural gels: crystal-chemistry of short range ordered components in Al, Fe, and Si systems  

Energy Technology Data Exchange (ETDEWEB)

In this review, the most important inorganic natural gels are presented: opal, aluminosilicate (allophanes) and hydrous iron oxides and silicates. It is demonstrated that natural gels are ordered at the atomic scale. In allophanes, Al is distributed between octahedral and tetrahedral sites. The amount of Al increases as Al/Si ratio decreases. Si-rich allophane have a local structure around Al and Si very different of that is known in kaolinite or halloysite. Transformation of Si-rich allophanes to crystallized minerals implies dissolution-recrystallization processes. On the contrary, in iron silicate with Fe/Si = 0.72, Si and Fe environments are close to those found in nontronite. The gel transformation to Fe-smectite may occur by long range ordering during ageing. In ferric silicate gels, the similarity of local structure around Fe in poorly ordered precursors and what is known in crystallized minerals ...

1997-07-01

66

Hydrolysis kinetics of lead silicate glass in acid solution  

International Nuclear Information System (INIS)

Hydrolysis kinetics of the lead silicate glass (LSG) with 40 mol% PbO in 0.5 N HNO_3 aqueous acid solution was investigated. The surface morphology and the gel layer thickness were studied by scanning electron microscopy (SEM) micrographs. Energy dispersive X-ray spectroscopy (EDS) and inductively coupled plasma spectroscopy (ICP) were used to determine the composition of the gel layer and the aqueous solution, respectively. The silicon content of the dissolution products was determined by using weight-loss data and compositions of the gel layer and the solution. The kinetic parameters were determined using the shrinking-core-model (SCM) for rate controlling step. The activation energy obtained for hydrolysis reaction was Q_c_h_e = 56.07 kJ/mole. The diffusion coefficient of the Pb ions from the gel layer was determined by using its concentration in solution and in LSG. The shrinkage of the sample and ...

2009-06-01

67

Ecological problems of natural gas cleansing  

International Nuclear Information System (INIS)

Full text: Chemical-technology approaches allowing to intensification the prevention processes of gas hydrates formation at motion of gas-liquid stream of natural gas in system natural gas well - gas wire have been worked up. Technological regimes of treatment of gas stream have been determined. Linear correlation dependences inhibitor electrolytes contained hydrated ions with different ion radii and charges of subgroups of alkali elements with one - type electron configuration were obtained. Important physico-chemical parameters of electrolytes have been determined: activity; coefficients of activity, viscosity, diffusion; density; heat capacity; heat conductivity; surface tension and freezing-point. The features of continuous influence of inhibitory factors on process of gas flow at low temperatures and relatively high pressure differences ?P have been studied by using of technological installation modulating the system natural gas well - gas ...

2007-06-01

68

Structural design at the polymer surface interface in nanoporous silica polyamine composites  

British Library Electronic Table of Contents (United Kingdom)

The factors affecting the rate of silica leaching in alkaline aqueous media from surface silanized, nanoporous, amorphous, silica gels and from silanized silica gels that have been modified with polyamines to form the previously reported silica polyamine composites (SPCs), BP-1 and BP-2 have been investigated. Silanization with alkyl trichlorosilanes slows the rate of silica leaching relative to the unmodified silica gels. The use of bulkier aryl silanes somewhat decreases the silica leaching under the same conditions. Interestingly, after modification of the silanized silica with poly(allylamine) (PAA) to make BP-1, the leaching increases, but subsequent modification of the SPC with chloroacetic acid to make BP-2, quenches this increase. A mechanism explaining these results is discussed. ...

2011-01-01

69

Evaluation of gels obtained from acetylation of chitosan in heterogeneous medium  

International Nuclear Information System (INIS)

Chitosan was acetylated during 2, 5 and 10 h and physical gels were obtained at different polymer concentrations in N,N-dimethylacetamide containing 5% of LiCl. Acetylation was confirmed by infrared spectroscopy and "1"3C NMR, and degrees of acetylation in the range of 0.82-0.91 were determined by NMR. The O-acetylation degree (0.12-0.15) was exclusively determined by a volumetric method. Rheological studies showed that the storage modulus values were smaller for the more acetylated samples and increased with the temperature and the polymer concentration. All the gels presented storage modulus superior to loss modulus, evidencing more elastic than viscous characteristics. The results obtained in this work suggest a gelation process based on a balance between O and N-acetylation and intermolecular bonds. (author)

70

An investigation on physical properties of strontium hexaferrite nanopowder synthesized by a sol-gel auto-combustion process with addition of cationic surfactant  

British Library Electronic Table of Contents (United Kingdom)

In this study a novel sol-gel auto-combustion method, using n-decyltrimethylammonium bromide as a cationic surfactant, has been used to synthesize strontium hexaferrite nanocrystalline powder. The dried nitrate-citrate gel, prepared from a solution of ferric nitrate, strontium nitrate, citric acid, trimethylamine and cationic surfactant, exhibited an auto-combustion behavior after ignition in air. The formation reaction temperature, phase identification, crystallites size, particles size distribution and morphology of resultant strontium hexaferrite powder were investigated by DTA/TGA, FTIR, XRD, LPSA, TEM and SEM techniques. The results showed that in presence of the cationic surfactant, the combustion intensity increases and the crystallite size decreases. The crystallite size of stronti...

2007-01-01

71

Industrial Technologies Program: Chemicals  

Science.gov (United States)

Efficiency and Renewable Energy EERE Home | Programs & Offices | Consumer Information Chemicals Search Search Help Chemicals EERE » Industrial Technologies Program » Chemicals...

2011-10-01

72

Viscoelasticity of various gel films prepared from solvent-soluble constituents in coal; Sekitanchu no yobai kayoseibun kara sakuseishita shushu no gel maku no nendansei  

Energy Technology Data Exchange (ETDEWEB)

Viscoelasticity of gel films prepared from solvent-soluble constituents without ash of coal using the mixed solvent of carbon disulfide and N-methyl-2-pyrrolidinone (CS2-NMP) was measured to study the network structure of the constituents. In experiment, Upper Freeport coal and Zao Zhuang coal were used as specimens. Viscoelasticity of various gels with different weight fractions of solvent was measured by creep measurement under a fixed load and stress-strain analysis under variable loads. In the 2nd and 3rd creep measurements, although no large changes in elastic strain and viscoelastic strain were found, viscous strain gradually decreased with an increase in viscosity. In the case of small weight fraction of solvent, small viscous strain and viscoelastic strain were found, while slightly large elastic strain was found. It was thus suggested that this elastic strain is derived from not only physical cross-linked networks by coal-solvent ...

1996-10-28

73

Transbilayer and interbilayer phospholipid exchange in dimyristoylphosphatidylcholine/dimyristoylphosphatidylethanolamine large unilamellar vesicles  

International Nuclear Information System (INIS)

The rates of spontaneous interbilayer and transbilayer exchange of ["3H]dimyristoylphosphatidylcholine (["3H]DMPC) were examined in the DMPC and DMPC/dimyristoylphosphatidylethanolamine (DMPE) large unilamellar vesicles in the liquid-crystalline-, gel-, and mixed-phase states. DMPC desorption rates from either gel or liquid-crystalline phases containing DMPE are very similar to the corresponding rates from pure DMPC gel or liquid-crystalline phases. The authors proposed that the DMPC/DSPC behavior results from packing defects in gel phases composed of both DMPC and DSPC molecules because of the four-carbon difference in the acyl chain lengths of the two species. The present results strongly support this hypothesis because no such anomalous behavior is observed in DMPC/DMPE, which is similar to DMPC/DSPC in phase behavior but does not have the chain length difference. These results are not consistent ...

74

Streptococcus pneumoniae Isolates with Reduced Susceptibility to Ciprofloxacin in Spain: Clonal Diversity and Appearance of Ciprofloxacin-Resistant Epidemic Clones  

UK PubMed Central (United Kingdom)

Analysis of the pulsed-field gel electrophoretic profiles of 82 pneumococcal isolates with reduced susceptibility to ciprofloxacin (RSC) and of 90 co-occurring susceptible isolates indicates a considerable...Full Text Available

2001-10-01

76

Relationships between distribution of lead in erythrocytes in vivo and in vitro and inhibition of ALA-D.  

UK PubMed Central (United Kingdom)

Proteins in the ALA-D (delta-aminolaevulinic acid dehydratase) fraction from gel filtration of erythrocyte supernatant (ES) have the highest affinity for lead among erythrocyte constituents in vivo...Full Text Available

1982-11-01

77

Polyamine Oxidase from Water Hyacinth  

UK PubMed Central (United Kingdom)

Polyamine oxidase was purified to homogeneity from leaves of water hyacinth by the criterion of sodium dodecyl sulfate gel electrophoresis (SDS disc PAGE). The enzyme showed a high specificity for spermidine...Full Text Available

1987-12-01

78

Partial Purification and Characterization of Aminopeptidase II from Chara australis  

UK PubMed Central (United Kingdom)

Aminopeptidase II, one of the two major aminopeptidases in the giant alga Chara australis, was partially purified. Its molecular weight was estimated to be about 80,000 by gel permeation...Full Text Available

1989-02-01

79

MudPIT Analysis: Application to Human Heart Tissue  

UK PubMed Central (United Kingdom)

Although two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) has been used as the standard proteomic approach for separating proteins in a complex mixture, this technique has many drawbacks....Full Text Available

2009-01-01

80

Location of an epitopic site on epiglycanin by molecular immunoelectron microscopy.  

UK PubMed Central (United Kingdom)

Antibodies of the IgM type present in rabbit anti-epiglycanin antiserum were purified by (NH4)2SO4 precipitation and by ion-exchange, affinity and gel-filtration chromatography. After papain treatment...Full Text Available

1985-04-01

81

Isolation of caprine arthritis encephalitis virus from goats in Mexico.  

UK PubMed Central (United Kingdom)

A lentivirus was isolated from 2 goats in Mexico that were seropositive to caprine arthritis encephalitis virus (CAEV) by the agar gel immunodiffusion (AGID) test. The lentivirus was identified as CAEV...Full Text Available

1999-07-01

82

Ion transport properties of lithium ionic liquids and their ion gels  

International Nuclear Information System (INIS)

A new series of lithium ionic liquids were prepared by introducing of two electron-withdrawing trifluoroacetyl groups in borate salts containing two methoxy-oligo(ethylene oxide) groups in the structures. Successive substitution reactions of oligo-ethylene glycol monomethyl ether and trifluroacetic acid from LiBH_4 yielded the lithium salts, which were clear and colorless liquids at room temperature. The fundamental physicochemical properties, such as density, thermal property, viscosity, ionic conductivity, self-diffusion coefficients, and electrochemical stability, were measured. The lithium ionic liquids had self-dissociation ability and conducted ions even in the absence of organic solvents. New polymer electrolytes, named 'ion gels', were prepared by radical cross-linking reactions of a poly(ethylene oxide-co-propylene oxide)tri-acrylate macromonomer in the presence the lithium ionic liquid. An increase in the glass transition temperatures (T _g) of the ion ...

2005-06-30

83

Improvement on CRUD removal efficiency by ion exchange resins  

Energy Technology Data Exchange (ETDEWEB)

Reduction of occupational radiation exposure dose in a BWR plant is achieved by an elimination of crud in a BWR primary loop condensate stream by condensate demineralizer. Crud removal by condensate polisher improves year by year, a phenomenon called the Aging Effect of Ion Exchange Resins. The cause of this phenomenon is assumed to be mainly due to changes in the cation resin property becoming more crud adsorptive, where a typical change in physical property of aged cation resin is an increase in water retention capacity. Assuming that the crud removal efficiency was influenced by a crosslinkage of cation resin, an attempt was made to enhance this removal efficiency by decreasing the crosslinkage and satisfactory results were obtained. As a result, new gel type cation resins were developed with lower crosslinkage and larger surface areas, as compared with conventional gel type resins. The crosslinkage degree of these new cation resins are ...

1989-10-01

84

Improvement on CRUD removal efficiency by ion exchange resins  

International Nuclear Information System (INIS)

Reduction of occupational radiation exposure dose in a BWR plant is achieved by an elimination of crud in a BWR primary loop condensate stream by condensate demineralizer. Crud removal by condensate polisher improves year by year, a phenomenon called the Aging Effect of Ion Exchange Resins. The cause of this phenomenon is assumed to be mainly due to changes in the cation resin property becoming more crud adsorptive, where a typical change in physical property of aged cation resin is an increase in water retention capacity. Assuming that the crud removal efficiency was influenced by a crosslinkage of cation resin, an attempt was made to enhance this removal efficiency by decreasing the crosslinkage and satisfactory results were obtained. As a result, new gel type cation resins were developed with lower crosslinkage and larger surface areas, as compared with conventional gel type resins. The crosslinkage degree of these new cation resins are ...

85

Improved Understanding of the Bacterial Vaginal Microbiota of Women before and after Probiotic Instillation  

UK PubMed Central (United Kingdom)

The vaginal bacterial microbiota of 19 premenopausal women was examined by PCR-denaturing gradient gel electrophoresis (DGGE) and sequencing of the V2-V3 region of the 16S rRNA gene. Ten of the women...Full Text Available

2003-01-01

86

Ethylene Regulates Monomeric GTP-Binding Protein Gene Expression and Activity in Arabidopsis1  

UK PubMed Central (United Kingdom)

Ethylene rapidly and transiently up-regulates the activity of several monomeric GTP-binding proteins (monomeric G proteins) in leaves of Arabidopsis as determined by two-dimensional gel electrophoresis...Full Text Available

2003-04-01

87

Electron spin resonance probe for the solvation of ionomer membranes and other microscopically heterogeneous systems. Cu[sup 2+] in nafion, sephadex and silica gel  

Energy Technology Data Exchange (ETDEWEB)

Cu[sup 2+] is a sensitive electron spin resonance (ESR) probe for the penetration of various polar solvents in membranes made of Nafion and as an indicator for the replacement of one solvent by another. The ESR parameters (g and [sup 63]Cu hyperfine tensors) can be translated into a structure of the solvent around the cation. The replacement of a solvent in the membrane by another depends on the polarity of the two solvents. The solvent with the largest dielectric constant, N-methylformamide (NMF), can be replaced by water but not by methanol or acetonitrile (dielectric constants 182, 78.5, 32.7, and 37.5, respectively). Preferential solvation of the cation by water in three water/acetonitrile mixtures (9:1, 1:1, and 1:9 by volume) in contact with silica gel, Sephadex, and Nafion has been observed in various degrees. Nafion is most selective, followed by Sephadex and by silica gel. The selectivity appears to be related to electrostatic ...

1992-01-01

88

Characterization of a pigment-dispersing hormone in eyestalks of the fiddler crab Uca pugilator  

UK PubMed Central (United Kingdom)

A pigment-dispersing hormone (PDH) from eyestalks of the fiddler crab Uca pugilator has been purified by gel filtration, ion-exchange chromatography, partition chromatography, and reversed-phase...Full Text Available

1985-08-01

89

Assessing phytoremediation potentials of selected tropical plants for acrylamide  

Science.gov (United States)

In biotechnology, acrylamide is being used in DNA and RNA analysis using the polyacrylamide gel electrophoreses procedure. Polymerized acrylamide is degraded into acrylamide through time; it is converted into a hazardous contaminant that is carcinogenic and neurotoxic to animals and humans. Because ...

90

Adenosine 5?-triphosphate sulphurylase from Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

1. ATP sulphurylase from Saccharomyces cerevisiae was purified 140-fold by using heat treatment, DEAE-cellulose chromatography and Sepharose 6B gel filtration. 2. The enzyme was stable...Full Text Available

1973-07-01

91

MRI evaluation and image processing in gel dosimetry. A study of selected MRI properties and image processing in 3D gel dosimetry  

Energy Technology Data Exchange (ETDEWEB)

Gel dosimetry is a new dosimetry method applied in radiation therapy. Gel dosimeters consist of a radiation sensitive gel, which can integrate absorbed doses from several radiation sources or beams. The dose to the gel can be evaluated by magnetic resonance imaging (MRI), a procedure that is the focus of the present thesis. A robust tool for the evaluation of the nonuniformity in MRI has been developed, the Deviation Image method. Unlike previously presented methods, the Deviation Image method includes all nonuniformity variations across a phantom surface and is insensitive to stochastic noise. Methods for the estimation of stochastic noise were analyzed in terms of sensitivity to nonuniformities. A method that averages the stochastic noise level over five regions over the phantom surface, and a method that assesses the stochastic noise level from the background, were found to be the methods of choice. ...

2001-03-01

92

Zn/gelled 6M KOH/O{sub 2} zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

The gel electrolyte for the zinc-air cell was prepared by mixing hydroponics gel with a 6M potassium hydroxide aqueous solution. The self-discharge of cells was characterized by measuring the open-circuit voltage. The effect of a discharge rate of 50mA constant current on cell voltage and plateau hour, as well as the voltage-current and current density-power density were measured and analysed. The electrode degradation after discharge cycling was characterized by structural and surface methods. The oxidation of the electrode surface further blocked the utilization of the Zn anode and was identified as a cause for the failure of the cell. (author)

2006-09-13

93

The effects of a timolol maleate gel-forming solution on normotensive beagle dogs.  

Science.gov (United States)

The effects of a timolol maleate gel-forming solution (TMGS) on intraocular pressure (IOP), blood pressure (BP), and pupil size (PS) were evaluated in normotensive dogs. TMGS was administered once daily to six normotensive beagle dogs. TMGS administration reduced IOP and PS. The hypotensive effect persisted for 24 hr after the administration. The mean reduction in IOP was 5.3 mm Hg (P<0.01). The changes in BP and PS were not significant. These results suggest that TMGS can potentially be used in the treatments of glaucoma and ocular hypertension in dogs. PMID:16820724

2006-06-01

94

Growth of epitaxial LaAlO{sub 3} and CeO{sub 2} films using sol-gel precursors  

Energy Technology Data Exchange (ETDEWEB)

LaAlO{sub 3} and CeO{sub 2} films have been successfully grown using sol-gel precursors. LaAlO{sub 3} precursor solution has been prepared from a metal alkoxide route and spun-cast on a SrTiO{sub 3} (100) single crystal to yield an epitaxial film following pyrolysis at 800{degrees}C in a rapid thermal annealer. A CeO{sub 2} precursor solution has been made using both an aqueous and an alkoxide route.

1996-04-01

95

Effect of different fuels on the strontium hexaferrite nanopowder synthesized by a surfactant-assisted sol-gel auto-combustion method  

British Library Electronic Table of Contents (United Kingdom)

In this research a sol-gel auto-combustion route has been proposed to synthesize strontium hexaferrite nanopowder, using metal nitrates, ammonia as pH adjusting agent, n-decyltrimethylammonium bromide as a cationic surfactant and different fuels such as citric acid, glycine, acetylacetone and oxalic acid. The formation temperature of strontium hexaferrite and its crystallite size in presence of different fuels were compared together. The results showed the lowest formation temperature as well as the smallest crystallite size in the presence of citric acid as 900degreeC and 37.3nm respectively.

2007-01-01

96

CaSnO3:. a high capacity anode material for Li-ion batteries  

Science.gov (United States)

Calcium stannate (CaSnO3) powders with the distorted perovskite structure have been synthesized by solid state and the sol-gel methods and their electrochemical performance was compared. The sol-gel CaSnO3 shows stable cycling performance with a reversible capacity of 430-440 mAh/g (0.005-1.0 V; 60 mA/g) up to 50 cycles. The role of preparatory conditions, morphology and cycling conditions (current density and potential window) on the anodic performance of the compounds are addressed.

2002-12-01

97

Chemical Reactor Diagnostics  

International Science & Technology Center (ISTC)

Development of Methods and Apparatus for Processes Diagnostics in Plasma Reactors at the Neutralization of Chemical Herbiside and Pestiside

98

Chemical Emergencies  

Medline Plus

English - Chemical Emergencies Click to Stop Video Click to Start Video To Listen to the Audio or ...

99

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

Science.gov (United States)

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 ...

2006-09-13

100

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

Energy Technology Data Exchange (ETDEWEB)

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 ...

2006-09-13

101

Prediction of Chemicals Ecotoxicity  

International Science & Technology Center (ISTC)

Computer-Aided Prediction of Chemical Ecotoxicity on the basis of Quantitative Structure-Activity Relationships with the Use of Physico-Chemical Descriptors, Including H-bond Parameters

102

Cell proliferation and chemical carcinogenesis: symposium overview.  

UK PubMed Central (United Kingdom)

Cancer, by definition, is a proliferative disease. The fundamental scientific issue explored at the international symposium "Cell Proliferation and Chemical Carcinogenesis" was the impact of chemically...Full Text Available

1993-12-01

103

CHEMICAL LEUCODERMA: INDIAN SCENARIO, PROGNOSIS, AND TREATMENT  

UK PubMed Central (United Kingdom)

Chemical leucoderma is an industrial disorder in developed countries and the common causative chemicals are phenols and catechols. Due to stringent controls and preventive measures the incidence has...Full Text Available

2010-07-01

104

Oil palm empty fruit bunch (OPEFB) fiber reinforced PVC/ENR blend-electron beam irradiation  

Energy Technology Data Exchange (ETDEWEB)

The effect of irradiation on the tensile properties of oil palm empty fruit bunch (OPEFB) fiber reinforced poly(vinyl chloride)/epoxidized natural rubber (PVC/ENR) blends were studied. The composites were prepared by mixing the fiber and the PVC/ENR blend using HAAKE Rheomixer at 150 deg. C. The composites were then irradiated by using a 3.0 MeV electron beam machine at doses ranging from 0 to 100 kGy in air and room temperature. The tensile strength, Young's modulus, elongation at break and gel fraction of the composites were measured. Comparative studies were also made by using poly(methyl acrylate) grafted OPEFB fiber in the similar blend system. An increase in tensile strength, Young's modulus and gel fraction, with a concurrent reduction in the elongation at break (Eb) of the PVC/ENR/OPEFB composites were observed upon electron beam irradiation. Studies revealed that grafting of the OPEFB fiber with methyl acrylate did ...

2007-12-15

105

Visible light photocatalytic activity and Photoelectrochemical property of Fe-doped TiO2 hollow spheres by sol?gel method  

British Library Electronic Table of Contents (United Kingdom)

Fe-doped TiO2 hollow spheres (Fe-THs) were synthesized by sol?gel process using carbon spheres as templates. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV?vis diffuse reflectance spectrum (DRS), N2 adsorption?desorption isotherms, Electron paramagnetic resonance (EPR) spectroscopy and Photoluminescence emission spectroscopy (PL). UV?vis spectra showed that Fe3+ doping could extend the absorption edge to the visible region. EPR spectra showed that Fe3+ was incorporated into the crystal lattice of TiO2, which could inhibit the recombination of photo-induced electron?hole pairs and improve the photocatalytic activity. The photocatalytic activities of the prepared samples were evaluated for the degradation of dye Reactive Brillia...

2011-01-01

106

Up-conversion luminescence saturation under pulsed excitation of erbium-doped, SiO_2-TiO_2 sol-gel powders  

International Nuclear Information System (INIS)

The intensity of erbium up-conversion luminescence could be limited by a saturation effect due to increased pump power. We studied the luminescence saturation of the 550 nm emission on erbium-doped, SiO_2-TiO_2 sol-gel powders under pulsed excitation at 979 and 1532 nm. From the latter, the up-converted luminescence intensity decreased with increasing excitation power, whereas no saturation was observed at 979 nm excitation. We proposed that the saturation effect is determined by the pump power, the erbium content and the lifetime of the corresponding first excited states at different pumping schemes.

2010-12-01

107

Tris(2,2prime-bipyridyl)ruthenium(II) electrogenerated chemiluminescence sensor based on carbon nantube dispersed in sol-gel-derived titania-Nafion composite films  

British Library Electronic Table of Contents (United Kingdom)

A highly sensitive and stable tris(2,2prime-bipyridyl)ruthenium(II) (Ru(bpy)32+) electrogenerated chemiluminescence (ECL) sensor was developed based on carbon nanotube (CNT) dispersed in mesoporous composite films of sol-gel titania and perfluorosulfonated ionomer (Nafion). Single-wall (SWCNT) and multi-wall carbon nanotubes (MWCNT) can be easily dispersed in the titania-Nafion composite solution. The hydrophobic CNT in the titania-Nafion composite films coated on a glassy carbon electrode certainly increased the amount of Ru(bpy)32+ immobilized in the ECL sensor by adsorption of Ru(bpy)32+ onto CNT surface, the electrocatalytic activity towards the oxidation of hydrophobic analytes, and the electronic conductivity of the composite films. Therefore, the present ECL sensor based on the CNT-...

2006-01-01

108

Silica-reinforced natural rubber prepared by the sol-gel process of ethoxysilanes in rubber latex  

British Library Electronic Table of Contents (United Kingdom)

Silica-reinforced natural rubber (NR) composite was prepared by using tetraethoxysilane (TEOS) as a precursor to generate silica particles inside the rubber. The silica was generated in situ by the sol-gel process of TEOS that was mixed directly into commercial-graded NR latex having 60% dry rubber content and 0.7% ammonia. The conversions of TEOS to silica inside the rubber were ranging from 90 to 97%. The silica particles dispersed evenly without extensive aggregation with sizes between 100 and 500 nm, as determined by scanning electron microscopy (SEM). An experimental design methodology, namely "two-level factorial design," was used to evaluate the influence of the amounts of TEOS, ammonia, and gelation time on the tensile modulus, tensile strength, and tear strength of the vulcanizate...

2008-01-01

109

Polymer-metal complex as gel electrolyte for quasi-solid-state dye-sensitized solar cells  

International Nuclear Information System (INIS)

A kind of polymer-metal complex gel electrolyte is successfully prepared and is used in dye-sensitized solar cells. Raman and X-ray photoelectron spectroscopy confirm the structure of this complex and is found that the metal ion reacts with nitrogen in the polymer. This novel electrolyte shows apparent diffusion coefficient of iodide of 8.37 x 10-7 cm2 s-1 and the energy conversion efficiency of 6.10% when the amount of ZnI2 is 0.04 M. By studying the dissociation active energy of the inorganic salt in electrolytes, we find that the metal salts can dissociate more easily after reacting with polymer and as a result can provide extra free iodide ion. The cell maintains ca. 93% of its initial efficiency after 20 d without further sealing, which shows good long-time stability.

2011-01-01

110

Optical properties and up-conversion of Pr"3"+ doped CdS nanoparticles in sol-gel glasses  

International Nuclear Information System (INIS)

Silica glasses containing Pr"3"+ with and without CdS nanoparticles were prepared by sol-gel technique. The influence of CdS nanoparticles on Pr"3"+ doped glass was studied by absorption, photoluminescence and up-conversion. From the measured intensities of various absorption bands of these glasses, the Judd-Ofelt parameters ?_2, ?_4 and ?_6 have been evaluated. The radiative transition probability (A), radiative lifetime (?_R), branching ratio (?_R) and integrated emission cross-section (?_P) were calculated from excited states of "3P_1 and "3P_0 levels. The up-conversion emissions were found in the green, orange and red regions under 800 nm excitation with peaks 559, 612 and 688 nm respectively. On excitation with 370 nm also leads to similar green, orange and red regions.

2010-10-01

111

Mechanism of the retention of ion associates of heteropoly acids with trioctylamine on a nitrile phase  

International Nuclear Information System (INIS)

The separation and the mechanism of retention of ion associates of #alpha#-isomers of molybdic and tungstic heteropoly acids (HPA) of phosphorus(5), silicon(4), and germanium(4) with trioctylamine (TOA) on a column (80x3 mm) packed with Diasorb-130-CN (8 #mu#m) were studied in a flow of chloroform-tetrahydrofuran (THF) and chloroform-n-butanol-TOA mixtures with spectrophotometric detection at 320 nm. It is demonstrated that the adsorption of all the studied ion associates proceeds through the displacement THF molecule from the surface of the stationary phase and without the displacement of TOA molecules. Conditions for the separation of phospho- and silicomolybdic HPA and also phospho- and germanolybdic HPA were found. The chromatographic system using silica gel modified with nitrile groups as the stationary phase is of higher selective than that using ummodified silica gel.

112

Electrochemical and optical properties of sol-gel derived CeO{sub 2} and mixed CeO{sub 2}/SnO{sub 2} coatings  

Energy Technology Data Exchange (ETDEWEB)

Ion storage CeO{sub 2} and CeO{sub 2}/SnO{sub 2} coatings were prepared by sol-gel dip-coating method using aqueous-based process. The influence of added SnO{sub 2} in the CeO{sub 2} oxide coatings on the inserted/extracted charge was determined by chronocoulometric measurements. It was found that for 60 nm thick film the inserted/extracted charge was twice larger (Q = 10mC/cm{sup 2}) for films containing 17 mol % SnO{sub 2} if compared to pure CeO{sub 2}. The addition of SnO{sub 2} to the mixed oxides coatings on their optical properties and structural characteristics were studied.

1994-12-31

113

Effects of manganese doping on properties of sol-gel derived biphasic calcium phosphate ceramics  

British Library Electronic Table of Contents (United Kingdom)

We have investigated the effect of manganese (Mn) doping on properties of nanosized biphasic calcium phosphate powders and their dense bodies. Manganese levels of 0.6, 1.3, 1.9, 4.3, 7.0 and 11.9at.% were successfully incorporated into biphasic calcium phosphate via a sol-gel route. The prepared powders were calcined at temperatures of 500-1200^oC. The X-ray diffraction analysis revealed that a mix phase comprising of hydroxyapatite and @b-tricalcium phosphate were present, however the content of each phases in the structure was affected by the Mn content. The studies found that the largest portion of @b-tricalcium phosphate was detected at 4.3at.% Mn doping. The incorporation of Mn has also greatly increased the crystallinity of the biphasic calcium phosphate powder due to progressive den...

2011-01-01

114

Dielectric and thermal characteristics of gel grown single crystals of ytterbium tartrate trihydrate  

British Library Electronic Table of Contents (United Kingdom)

Dielectric and thermal characteristics of gel grown single crystals of ytterbium tartrate trihydrate have been carried out. The dielectric constant has been measured as a function of frequency in the range 2?kHz?1?MHz and temperature range 30?300??C. The dielectric constant increases with temperature, attains a peak near 215??C, and then decreases as the temperature exceeds 215??C. The dielectric anomaly at 215??C is suggested to be due to phase transition brought about in the material. The dielectric behaviour of the material is correlated with the results on thermal analysis. Thermogravimetric and differential thermal analysis have been used to study the thermal characteristics of the material. The experimental results show that the material is thermally stable up to 200??C. The decompos...

2007-01-01

115

Detection of glycoproteins in the Acanthamoeba plasma membrane  

International Nuclear Information System (INIS)

In the present study the authors have shown that glycoproteins are present in the plasma membrane of Acanthamoeba castellanii by utilizing different radioactive labeling techniques. Plasma membrane proteins in the amoeba were iodinated by "1"2"5I-lactoperoxidase labeling and the solubilized radiolabeled glycoproteins were separated by lectin-Sepharose affinity chromatography followed by polyacrylamide gel electrophoresis. The periodate/NaB"3H_4 and galactose oxidase/NaB"3H_4 labeling techniques were used for labeling of surface carbohydrates in the amoeba. Several surface-labeled glycoproteins were observed in addition to a diffusely labeled region with M_r of 55,000-75,000 seen on electrophoresis, which could represent glycolipids. The presence of glycoproteins in the plasma membrane of Acanthamoeba castellanii was confirmed by metabolic labeling with ["3"5S]methionine followed by lectin-Sepharose affinity chromatography and polyacrylamide gel ...

116

Contrast Sensitivity and Optical Quality of the Eye after Instillation of Timolol Maleate Gel-Forming Solution and Brinzolamide Ophthalmic Suspension  

British Library Electronic Table of Contents (United Kingdom)

Purpose To investigate the influence of timolol maleate 0.5% gel-forming solution and brinzolamide 1% ophthalmic suspension on contrast sensitivity, ocular higher-order aberration (HOA), and corneal surface light scattering. Design Prospective, comparative study. Participants Forty normal volunteers were enrolled in this study. Methods We evaluated contrast sensitivity, ocular HOA, and corneal light scattering before and 2, 5, 10, and 15 minutes after instillation of antiglaucoma eyedrops. Contrast sensitivity function was assessed with the CSV-1000RN chart (Vector Vision Co., Greenville, OH). Higher-order aberration was measured for a 4-mm pupil using the Hartmann-Shack aberrometer (KR-9000PW; Topcon, Tokyo, Japan). Corneal surface light scattering was quantitatively evaluated by using th...

2010-01-01

117

ALK, the Key Gene for Gelatinization Temperature, is a Modifier Gene for Gel Consistency in Rice  

British Library Electronic Table of Contents (United Kingdom)

Abstract Gelatinization temperature (GT) is an important parameter in evaluating the cooking and eating quality of rice. Indeed, the phenotype, biochemistry and inheritance of GT have been widely studied in recent times. Previous map-based cloning revealed that GT was controlled by ALK gene, which encodes a putative soluble starch synthase II-3. Complementation vector and RNAi vector were constructed and transformed into Nipponbare mediated by Agrobacterium. Phenotypic and molecular analyses of transgenic lines provided direct evidence for ALK as a key gene for GT. Meanwhile, amylose content, gel consistency and pasting properties were also affected in transgenic lines. Two of four nonsynonymous single nucleotide polymorphisms in coding sequence of ALK were identified as essential for GT. ...

2011-01-01

128

Massage Therapy  

Medline Plus

... Massage therapy can help the body release certain chemicals. These chemicals help us relax, improve blood circulation and get ...

129

Laboratory evaluation of the feasibility of chemical oxidation processes for treatment of contaminated groundwaters. Final report  

Energy Technology Data Exchange (ETDEWEB)

Chemical oxidation is a treatment technology that uses powertul chemical oxidizers to destroy organic contaminants. Typical oxidizers used in chemical oxidation processes include ozone, hydrogen peroxide, chlorine, and potassium permanganate. The chemical reaction products are usually simple organic compounds, such as carboxylic acids, and/or inorganic compounds, such as carbon dioxide, water, and simple inorganic complexes (e.g., chloride salts, in the case of chemical oxidation treatment of chlorinated solvents).

1995-09-01

130

Coatings with controlled porosity and chemical properties  

Energy Technology Data Exchange (ETDEWEB)

Coatings and sensors having both steric and chemical selectivity. Controlled porosity provides the steric selectivity, whereas chemically tailored film properties, using controlled composition or modification by coupling agents, chemical species replacement, or chemical species within pores, provide the chemical selectivity. Single or multiple layers may be provided.

1996-01-01

131

The Effect of Cocktail on Radiocarbon Analysis by Direct Absorption of Carbon dioxide  

International Nuclear Information System (INIS)

Carbon-14 was analysed by direct absorption of carbon dioxide on the mixture of organic amine compound and scintillation cocktail then counted by low level liquid scintillation counter. This method can be applied for radiocarbon dating. In this study, the effects of carbon dioxide absorption, and counting efficiency were investigated using various commercial available cocktail. It was found that permafluor V and Ready Gel showed the highest carbon dioxide absorption whereas the Permafluor V showed the highest counting efficiency

1998-12-01

132

Rhizobium fredii and Rhizobium meliloti produce 3-deoxy-D-manno-2-octulosonic acid-containing polysaccharides that are structurally analogous to group II K antigens (capsular polysaccharides) found in Escherichia coli.  

UK PubMed Central (United Kingdom)

The polysaccharide components from cultured cells of Rhizobium fredii USDA205 and Rhizobium meliloti AK631 were extracted with hot phenol-water and separated by repetitive gel filtration chromatography....Full Text Available

1993-06-01

133

Purification by Immunoadsorption and Immunochemical Properties of NADP-Dependent Malic Enzymes from Leaves of C3, C4, and Crassulacean Acid Metabolism Plants  

UK PubMed Central (United Kingdom)

NADP:malic enzyme from corn (Zea mays L.) leaves was purified by conventional techniques to apparent homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis....Full Text Available

1990-03-01

134

Passive, integrated measurement of radon using 5A synthetic zeolite and blue silica gel  

Energy Technology Data Exchange (ETDEWEB)

Synthetic zeolite of 0.5 nm pore size (5A) and blue silica gel were tested to determine their capability to be used as radon collectors. Tests conducted in a radon chamber under controlled conditions of temperature and relative humidity indicate that simple, inexpensive and maintenance-free passive devices containing about 250 g of synthetic zeolite or about 270 g of blue silica gel in open face metal canisters that can measure radon conveniently and adequately, the latter though being suitable only for dry-medium dry atmosphere with quite high radon concentrations. Both materials can be recycled for reuse, in a way similar to the recycle and reuse of active carbon. The amount of radon adsorbed in such collectors is determined by counting the gamma rays from the radon decay products. The lower limit of detection (LLD) is estimated to {approx}45 Bqm{sup -3} for the synthetic zeolite and to {approx}350 Bqm{sup -3} for the blue silica ...

2010-01-15

135

Measurement of radon emanation rates using activated charcoal  

Energy Technology Data Exchange (ETDEWEB)

The use of charcoal canisters in the measurement of radon emanation rates from surfaces is discussed. The counting efficiency of the canisters is dependent upon the volume of activated charcoal used, varying from approximately 0.7% for a full canister to 1.3% for a canister filled to only 1/3 of its capacity. The inclusion of Si-Gel desiccant reduces the radon collection efficiency of the canister.

1983-07-01

136

Isoelectric focusing purity criteria and "1H NMR detectable spectroscopic heterogeneity in the major isolated monomer hemoglobins from Glycera dibranchiata  

International Nuclear Information System (INIS)

Three major monomeric hemoglobins have been isolated from the erythrocytes of Glycera dibranchiata. Their importance to structure-function studies of heme proteins lies in the fact that they have been shown to possess an exceptional amino acid substitution. In these proteins, the E-7 position is occupied by leucine rather than the more common distal histidine. This substitution alters the polarity of the heme ligand binding environment compared to myoglobin. Due to this, the G. dibranchiata monomer hemoglobins are attracting much attention. However, until now no purity criterion has been developed. Here the authors demonstrate that, for all of the Glycera momomer hemoglobins, multiple line patterns are shown on high-voltage isoelectric focusing (IEF) gels. Most of these lines are shown to be a consequence of heme-related phenomena and can be understood on the basis of changes in oxidation and ligation state of the heme iron. The multiple line pattern does not ...

137

Double minutes arise from circular extrachromosomal DNA intermediates which integrate into chromosomal sites in human HL-60 leukemia cells.  

UK PubMed Central (United Kingdom)

Amplification of oncogenes has been found to be an important prognostic factor in behavior of patients' malignancies. In this study we have used new gel electrophoresis techniques to follow the location...Full Text Available

1990-06-01

138

Detonation of explosives  

Energy Technology Data Exchange (ETDEWEB)

In recent years new, less-sensitive explosives have been developed together with new types of detonator. Four sections are covered: 1) Description of various developments achieved by the laboratories of Nobel Explosifs over the past 12 years; 2) Explanation of the limits of application of the various products; 3) Thoughts on the various detonator systems and their effectiveness; and 4) Advice and recommendations for the use of the new product range. The products in question are : dynamites, nitrates, oil nitrates, gels and slurry explosives. (17 refs.)

1983-04-01

139

Characterization of DTPA complexes and conjugated antibodies of astatine  

International Nuclear Information System (INIS)

The complex formation of astatine(I) cation with diethylene triamine pentaacetic acid (DTPA) and characterization of the complexes were investigated by electromigration in free electrolytes and by gel-chromatography on Sephadex G 25. The conjugation procedure for the production of At-DTPA conjugated polyclonal antibodies is described. (author) 15 refs.; 2 figs.

140

Antimicrobial resistance, virulence-associated genes, and pulsed-field gel electrophoresis profiles of Salmonella enterica subsp. enterica serovar Typhimurium isolated from piglets with diarrhea in Korea  

UK PubMed Central (United Kingdom)

Salmonella enterica subsp. enterica serovar Typhimurium was isolated from diarrheic piglets in 2 periods, 2000–2001 (n = 25) and 2005–2006...Full Text Available

2011-01-01

141

A Two-Dimensional Protein Gel Electrophoresis Study of the Heat Stress Response of Bacillus subtilis Cells during Sporulation  

UK PubMed Central (United Kingdom)

The heat resistance of spores of Bacillus subtilis formed at 30°C was enhanced by pretreatment at 48°C for 30 min, 60 min into sporulation, for all four strains examined....Full Text Available

2000-09-01

142

A Meta-analysis to Investigate the Relation Between Fitzpatrick Skin Types and Tolerability of Adapalene-Benzoyl Peroxide Topical Gel in Subjects with Mild or Moderate Acne  

UK PubMed Central (United Kingdom)

The overall goal of acne management for all patients is to select treatments that effectively address as many pathogenic factors as possible while minimizing side effects. Acne therapy in darker skin...Full Text Available

2010-08-01

143

Star-formation triggers and chemical evolution  

Energy Technology Data Exchange (ETDEWEB)

Comparative studies of flocculent and grand-design spirals suggest that density waves are not the predominant trigger of star formation in most galaxies. Implications for chemical evolution are profound. It may be possible to ignore the details of the spiral-wave phenomenon in research aimed at unifying the chemical properties of spiral disks. 16 references.

1986-10-01

144

Low-Level Exposure to Multiple Chemicals: Reason for Human Health Concerns?  

UK PubMed Central (United Kingdom)

BackgroundA key question in the risk assessment of exposures to multiple chemicals is whether mixture effects may occur when chemicals are combined at low doses which individually...Full Text Available

2007-12-01

145

Interactive Toxicity of Inorganic Mercury and Trichloroethylene in Rat and Human Proximal Tubules  

UK PubMed Central (United Kingdom)

Simultaneous or prior exposure to one chemical may alter the concurrent or subsequent response to another chemical, often in unexpected ways. This is particularly true when the two chemicals...Full Text Available

2007-06-15

146

Identification of environmental chemicals with estrogenic activity using a combination of in vitro assays.  

UK PubMed Central (United Kingdom)

Environmental chemicals that function as estrogens have been suggested to be associated with an increase in disease and dysfunctions in animals and humans. To characterize chemicals that may act as...Full Text Available

1996-10-01

147

Chemical activation of MEK1 - a redox trigger for evaluating the effects of phosphorylation.  

Science.gov (United States)

An approach to generate mimics of phosphorylated serine proteins chemically through site-specific sulfonation of cysteine is presented. This chemical modification is reversible in the presence of reducing agent and therefore is analogous to the kinase/phosphatase system used in nature. PMID:21717004

2011-06-30

148

Absence of morphologic correlation between chemical toxicity and chemical carcinogenesis.  

UK PubMed Central (United Kingdom)

The experimental data set used to evaluate site-specific histopathologic correspondence between the morphologic end points of toxicity and carcinogenicity comprises 130 chemical carcinogenesis studies....Full Text Available

1993-12-01

149

Molecular Genetics and Carcinogenesis Section  

Science.gov (United States)

The Molecular Genetics and Carcinogenesis Section conducts studies using human epithelial cells to assess: activation of proto-oncogenes by chemical and physical carcinogens; inactivation and dysregulation of tumor suppressor genes by chemical and physical

150

Hard Corrosion and Radiation-Resistant Coatings  

International Science & Technology Center (ISTC)

Hard Nano-Strutural Coatings Resistant to the Extreme Conditions of Chemical, Abrasive and High Energy Media for Thermonuclear Power, Oil and Gas and Chemical Industries

151

Environmental chemical-induced macrophage dysfunction.  

UK PubMed Central (United Kingdom)

Immunomodulation by environmental chemical contaminants and the role immune parameters play in toxicity and risk assessment studies is of increasing concern. Although considerable evidence has indicated...Full Text Available

1981-06-01

152

Chemical Carcinogenesis Testing and Related Issues ...  

Science.gov (United States)

... 6 lit. CHEMICAL CARCINOGENESIS TESTING AND RELATED ISSUES- ILn SUBCHRONIC STUDIES AND RELATED ISSUES 0 o Andrew Sivak 0 ...

1985-05-01

153

Atmospheric chemistry in volcanic plumes  

UK PubMed Central (United Kingdom)

Recent field observations have shown that the atmospheric plumes of quiescently degassing volcanoes are chemically very active, pointing to the role of chemical cycles involving halogen species and...Full Text Available

2010-04-13

154

Approaches to the evaluation of chemical-induced immunotoxicity.  

UK PubMed Central (United Kingdom)

The immune system plays a crucial role in maintaining health; however, accumulating evidence indicates that this system can be the target for immunotoxic effects caused by a variety of chemicals including...Full Text Available

1995-12-01

155

Application of Key Events Analysis to Chemical Carcinogens and Noncarcinogens  

UK PubMed Central (United Kingdom)

The existence of thresholds for toxicants is a matter of debate in chemical risk assessment and regulation. Current risk assessment methods are based on the assumption that, in the absence of sufficient...Full Text Available

2009-09-01

156

The Dixmier-Moeglin equivalence and a Gel'fand-Kirillov problem for Poisson polynomial algebras  

CERN Document Server

The structure of Poisson polynomial algebras of the type obtained as semiclassical limits of quantized coordinate rings is investigated. Sufficient conditions for a rational Poisson action of a torus on such an algebra to leave only finitely many Poisson prime ideals invariant are obtained. Combined with previous work of the first-named author, this establishes the Poisson Dixmier-Moeglin equivalence for large classes of Poisson polynomial rings, such as semiclassical limits of quantum matrices, quantum symplectic and euclidean spaces, quantum symmetric and antisymmetric matrices. For a similarly large class of Poisson polynomial rings, it is proved that the quotient field of the algebra (respectively, of any Poisson prime factor ring) is a rational function field $F(x_1,...,x_n)$ over the base field (respectively, over an extension field of the base field) with $\\{x_i,x_j\\}= \\lambda_{ij} x_ix_j$ for suitable scalars $\\lambda_{ij}$, thus establishing a quadratic Poisson version of ...

2007-01-01

157

Sunlight photocatalytic activity of CdS modified TiO2 loaded on activated carbon fibers  

British Library Electronic Table of Contents (United Kingdom)

To improve the photocatalytic application performances of TiO2, in this work, firstly CdS modified Degussa P25 TiO2 (CdS/TiO2) composites were prepared by two methods, sol-gel method and precipitation method. Next they, sol-gel-CdS/TiO2 (sg-CdS/TiO2) and precipitation-CdS/TiO2 (pp-CdS/TiO2), were loaded on activated carbon fibers (ACFs) by dip-coating method using the sodium carboxymethyl cellulose as adhesives. The composites were characterized by XRD, UV-vis absorbance spectra, SEM, EDS and BET. The photocatalytic activities under sunlight were investigated by the degradation of methylene blue. The results showed that CdS/TiO2 composites were mainly composed of anatase-TiO2 and little CdS cubic phases. The absorption wavelengths of sg-CdS/TiO2 and pp-CdS/TiO2 composites were extended to ...

2010-01-01

158

Structural Characterization and Photoluminescent Properties of (La1-xSmx)2Ti2O7 Solid Solutions Synthesized by a Sol-Gel Route  

British Library Electronic Table of Contents (United Kingdom)

Abstract A series of compounds with the general formula (La1-xSmx)2Ti2O7 (0-- x --1.0) has been synthesized by a sol-gel method and characterized by XRD, Raman spectroscopy, and scanning electron microscopy (SEM). These compounds are structurally isomorphic to perovskite-type La2Ti2O7 until a substitution rate of x = 0.8. Above this substitution rate (x >-0.8), a biphasic mixture is obtained between the substituted perovskite layered phase and the pyrochlore Sm2Ti2O7 phase. The unusual phosphor (La1-xSmx)2Ti2O7 has been elaborated and its luminescent properties were investigated for low rates of substitution. The emission and excitation spectra were used to study the luminescent properties. The (La1.9Sm0.1)2Ti2O7 powders emit bright red-orange lightunder UV excitation. The emission propert...

2011-01-01

159

Short-term tolerability of once-daily timolol hemihydrate 0.5%, timolol maleate in sorbate 0.5%, and generic timolol maleate gel-forming solution 0.5% in glaucoma and/or ocular hypertension: A prospective, randomized, double-masked, active-controlled, three-period crossover pilot study  

British Library Electronic Table of Contents (United Kingdom)

Objective: The aim of this study was to compare symptoms and anterior segment tolerability with short-term (3-day) administration of once-daily timolol hemihydrate 0.5%, timolol maleate in sorbate 0.5%, and generic timolol maleate gel-forming solution 0.5% in the treatment of glaucoma and/or ocular hypertension. Methods: In this prospective, randomized, double-masked, active-controlled, 3-period crossover pilot study, eligible patients had primary open-angle, pigmentdispersion, or exfoliation glaucoma, and/or ocular hypertension in >=1 eye; had a best corrected visual acuity of 1.0 or better in each eye, as measured using the Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity testing chart; were receiving 1 glaucoma medication; and had an untreated intraocular pressure (IOP) ...

2009-01-01

160

Sensitive detection of endocrine disrupters using ionic liquid - Single walled carbon nanotubes modified screen-printed based biosensors.  

Science.gov (United States)

Simple and low cost biosensor based on screen-printed electrode for sensitive detection of some alkylphenols was developed, by entrapment of HRP in a nanocomposite gel based on single-walled carbon nanotubes (SWCNTs) and 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF(6)]) ionic liquid. Raman and FTIR spectroscopy, CV and EIS studies demonstrate the interaction between SWCNTs and ionic liquid. The nanocomposite gel, SWCNT-[BMIM][PF(6)] provides to the modified sensor a considerable enhanced electrocatalytic activity toward hydrogen peroxide reduction. The HRP based biosensor exhibits high sensitivity and good stability, allowing a detection of the alkylphenols at an applied potential of -0.2V vs. Ag/AgCl, in linear range from 5.5 to 97.7?M for 4-t-octylphenol and respectively, between 5.5 and 140?M for 4-n-nonylphenol, with a response time of about 5s. The detection limit was 1.1?M for 4-t-octylphenol, and respectively 0.4?M for ...

2011-07-19

161

Preparation of nanostructure Ni doped CdO thin films by sol gel spin coating method  

British Library Electronic Table of Contents (United Kingdom)

The nanostructure Ni-doped CdO films have been prepared by sol gel spin coating method. Atomic force microscopy results indicate that the CdO films are formed from the nanoparticles and the grain size is changed with nickel content. X-ray diffraction patterns of the films indicate that the undoped and Ni-doped CdO films have polycrystalline structure with a cubic sodium chloride structure, showing two main characteristic peaks assigned to the (111) and (200) planes. The optical band gap values of undoped and Ni-doped CdO films were determined by optical absorption method. The Eg values of the CdO films were found to be in the range of 2.26?2.60?eV. The Eg values of the CdO films increase with the content of Ni dopant (up to 6% Ni). It is evaluated that the optical band gap and grain size o...

2011-01-01

162

Preparation of Eu-doped #beta#- and 15R-SiAlONs by ammonia nitridation of the precursor obtained using aluminum glycine gel  

International Nuclear Information System (INIS)

Synthesis of Eu-doped #beta#- and 15R-SiAlONs was studied by the ammonia nitridation of precursors derived from an #alpha#-Si_3N_4 fine powder dispersed in aluminum glycine gel with various Si/Al ratio and post-annealing in a nitrogen pressure furnace. The largest amount of #beta#-SiAlON was observed in the product at 1750 deg. C for Si/Al = 1/1 with small amounts of both #alpha#- and 15R-SiAlON impurities. The product showed two emissions at around 420 nm and 560 nm. The emission intensities decreased with increasing amount of #beta#-SiAlON. The former and latter emissions were assigned to Eu"2"+ in the 15R- and #alpha#-SiAlONs impurities. A mixture of Eu-doped 15R-SiAlON with #alpha#-Al_2O_3 impurity was obtained for Si/Al = 1/6, using AlN together with Al(NO_3)_3.9H_2O in a 2/1 atomic ratio as the aluminum source. It showed a bluish-white emission at 450 nm under 254 nm radiation.

2009-11-13

163

Mullite long fibres prepared by sol-gel method using water solvent systems  

Energy Technology Data Exchange (ETDEWEB)

Mullite long fibres, which are a candidate for high temperature applications were prepared by sol-gel method from water solvent systems. They were synthesized from three different combinations of raw materials as follows: (1):Al(O{sub 1}C{sub 3}H{sub 7}){sub 3}, Al-nitrate and Si(OC{sub 2}H{sub 5}){sub 4} (TEOS), (2):Al metal, Al-chloride and TEOS, (3):Al metal, Al-nitrate and TEOS. In the methods (1) and (2), very fine SiO{sub 2} aerosol particles were also used partially replacing TEOS. The prepared solutions were condensed and examined the spinability by a hand drawing method. Dense and crack free mullite fibres were prepared from the methods (1) and (3) by firing up to 1100 C. Whereas the fibres prepared from the method (2) were less SiO{sub 2} than mullite composition and were porous by the firing due to evaporation of residual Cl ions at high temperature. (orig.) 10 refs.

1997-12-31

164

Monovalent cation-induced structure of telomeric DNA: The G-quartet model  

Energy Technology Data Exchange (ETDEWEB)

We have investigated the structures formed by oligonucleotides composed of two or four repeats of the telomeric sequences from Oxytricha and Tetrahymena. The Oxytricha four-repeat molecule (d(T4G4)4 = Oxy-4) forms structures with increased electrophoretic mobility in nondenaturing gels containing Na+, K+, or Cs+, but not in gels containing Li+ or no added salt. Formation of the folded structure results in protection of a set of dG's from methylation by dimethyl sulfate. Efficient UV-induced cross-links are observed in Oxy-4 and the related sequence from Tetrahymena (d(T2G4)4 = Tet-4), and join thymidine residues in different repeats. Models proposed to account for these data involve G-quartets, hydrogen-bonded structures formed from four guanosine residues in a square-planar array. We propose that the G-quartet structure must be dealt with in vivo by the telomere replication machinery.

1989-12-01

165

Glass Transition Behaviors of Ethylene Glycol-Water Solutions Confined within Nano-Pores of Silica Gel  

Science.gov (United States)

Enthalpy relaxation properties of the ethylene glycol (EG) aqueous solutions confined within silica-gel void spaces of 1.1 nm in the average void thickness and 6, 12 and 52 nm in their average diameters were examined by an adiabatic calorimetry to understand the glass transition behavior of the solutions and the rearrangement processes of the molecules. The glass transition temperature Tg of EG was found to decrease with adding the water molecules which are mobile under the condition lacking in the full hydrogen-bond network. Meanwhile, the Tg in the water-rich region showed a rise towards pure water; after a phase separation in a 25 mol% (x = 0.25) EG solution, the Tg was 160 K which was higher than that derived by extrapolating the composition dependence to pure water. The Tg = 160 K is the same as observed in the pure water confined within 1.1 nm voids; this indicates the validity of the interpretation that the glass transition at 160 K of the confined water ...

2008-02-01

166

Crud removal performance with ion exchange resins in BWR plants  

Energy Technology Data Exchange (ETDEWEB)

It is needless to say that one of the most important roles of the condensate demineralizer in Japanese boiling water reactors (BWR) is to eliminate such impurities during accidental occurrence of sea water leakage from condensate cooling system. Ion exchange resins packed in condensate demineralizer have also been expected to decrease crud, or corrosion products (CP) in condensate water in order to finally reduce activated corrosion products (ACP) in the reactor coolant loop. It is perceived that crud removal ability of a condensate demineralizer has been improved year by year. And we call this phenomenon as `Aging Effect`. Typical property changes of aged cation exchange resin consisted of an increase of water retention capacity and a change of surface texture. Based on these findings, we formulated a new concept and developed new gel type ion exchange resins for the better crud removal. The results from column tests using actual condensate water for approximately ...

1996-01-01

167

Characterization of nanosized Tb-MCM-41 synthesized by the sol-gel-assisted self-assembly method  

International Nuclear Information System (INIS)

The nanosized luminescent Tb-MCM-41 (1:10) is synthesized by means of sol-gel-assisted self-assembly under basic conditions at room temperature. The results of "2"9Si-MAS NMR and XRD prove that Tb"3"+ doped Si-O framework. The HRTEM image shows that the regular uniform particles with a diameter of 10 nm possess ultralarge pore with diameter 2.0 nm, which is consistent with the result of N_2 adsorption. The BET surface area and porosity of Tb-MCM-41 (1:10) are 1127 m"2/g and 0.84 cm"3/g, respectively. The patterns of selected-area electron diffraction and XRD of Tb-MCM-41 (1:10) show an Fm3m space group in the cubic. FT-IR results show that the peaks near 970 cm"-"1 are assigned to the deformation vibration of silanol group. The as-products are calcined at 800 deg. C and the mesoporous materials possess enormous specific areas and large porosity, it shows that the mesoporous materials are ultrastable.

2003-10-06

168

Alkaline doped TiO2 sol-gel catalysts: Effect of sintering on catalyst activity and selectivity for acetone condensation  

British Library Electronic Table of Contents (United Kingdom)

In this paper, we prepared by the sol-gel method alkaline titania catalysts, doped by gelling titanium alkoxide with aqueous solutions containing potassium, rubidium or cesium chlorides. XRD patterns showed that samples annealed at 400 and 600degreeC contained a single crystalline phase, anastase. Specific surface areas were higher in samples annealed at 400degreeC (>100m2/g) than in those annealed at 600degreeC (25m2/g). The weight density of basic sites determined by CO2-TPD drastically diminished in samples treated at 600degreeC. Catalysts were tested for the self-condensation of acetone at 300degreeC; main reaction products were isomesityl oxide, mesityl oxide and mesitylene. Samples annealed at 600degreeC showed lower acetone conversion rate and low formation of mesitylene than that o...

2006-01-01

169

A single sorbent for tetracycline enrichment and subsequent solid-matrix time-resolved luminescence  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study was to search for a sorbent that could act as an extraction phase and as a support for solid-matrix time-resolved luminescence (SMTRL). Four potential sorbents were investigated for this purpose using tetracycline (TC) as a model analyte. Sorbents prepared from C18 silica gel or calcium cross-linked pectin gel were able to extract TC from dilute solutions. Europium(III)-TC complex adsorbed on the surface of C18 generated the most intense TRL signal when measured at {lambda}{sub ex} = 388 nm and {lambda}{sub em} = 615 nm. This method achieved a 1 ng/ml limit of detection (LOD) with a 100 {mu}l sample solution in a repeated spotting mode. Hyphenation of sorbent extraction and SMTRL was demonstrated using C18. This method is suitable for screening of TC in foods or aqueous solutions and can be extended to other luminescent lanthanide-chelating analytes in physiological or environmental samples.

2005-01-10

170

Synthesis and photonic band calculations of NCP face-centered cubic photonic crystals of TiO2 hollow spheres.  

Science.gov (United States)

With the help of self-assembly, thermal sintering, selective etching techniques and sol-gel process, the non-close packed (ncp) face-centered cubic (fcc) photonic crystals of titanium dioxide (TiO2) hollow spheres connected by TiO2 cylindrical tubes have been fabricated using silica template. The photonic bandgap calculations indicate that the ncp structure of TiO2 hollow spheres was easier to open the pseudogaps than close packed system at the lowest energy. PMID:17097102

2006-10-21

171

Quality engineering and control. Semiannual progress report, May-October 1979  

International Nuclear Information System (INIS)

The following are reported: colorimetric determination of Ti in Cr, decontamination of metals by anodic dissolution, computer code for x-ray peak identification, gel-permeation chromatography of CoRezyn 1664 polyester resin, infrared monitoring of gases and vapors, particle size analysis of dusts, nondestructive analysis of Oralloy for removable alpha contamination, dissolution (digestion) of high-fired oxides, assay of U in a Pu-U alloy, measurement of oxide thickness on Pu metal by x-ray diffraction, analysis of precipitated Pu peroxide, differentiation of Dowex SBR and 11 resins, and determination of Pu solubility in simulated lung fluid.

172

Phytic acid doped nanoparticles for green anticorrosion coatings  

British Library Electronic Table of Contents (United Kingdom)

In this paper, an environmentally friendly metal corrosion inhibitor, phytic acid, was assembled into the walls of silica nanoparticles via layer-by-layer self-assembly technique (LbL) with poly(allylamine hydrochloride). Such functionalized nanoparticles were uniformly distributed into sol-gel films for metal anticorrosion. The films showed very pronounced and lasting protective efficiency in concentrated salt aqueous solutions as indicated by electrochemical impedance spectroscopy (EIS) measurement. These results may provide a new route for the preparation of environment-friendly anticorrosion coatings.

2010-01-01

173

Impact of palladium silicide formation on the catalytic properties of Pd/SiO2 catalysts in liquid-phase semihydrogenation of phenylacetylene  

British Library Electronic Table of Contents (United Kingdom)

Palladium silicide was formed on the sol-gel derived SiO2 supported Pd catalysts prepared by ion-exchange method (Pd/SiO2-SG-ion). However, the catalysts exhibited superior performances than commercial SiO2 supported ones in liquid-phase semihydrogenation of phenylacetylene. It was probably due to an inhibition of a product of styrene, which is adsorbed on the surface of Pd, more strongly on Pd/SiO2-SG in which Pd is electron-deficient as shown by larger binding energy from XPS results.

2007-01-01

174

Heterogeneity effects in adsorption kinetics of gas mixtures. [C/sub 1/-C/sub 4/ hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

An analysis based on Jaroniec's theory of mixed gas adsorption showed that for two arbitrary adsorbing gas components the ratio of their surface coverages is a simple power function of the ratio of their partial pressures. This result was verified with available experimental data on the adsorption of C/sub 1/-C/sub 4/ hydrocarbon binary mixtures, CO/sub 2//C/sub 2/H/sub 4/, and N/sub 2//CO on various carbons, silica gel, and cesium iodide.

1980-01-01

175

Effects of temperature and the use of macroreticular resins in lithium isotope separation by displacement chromatography  

Energy Technology Data Exchange (ETDEWEB)

The effects of temperature and the use of macroreticular resins were studied in lithium isotope separation by an ion-exchange method. The isotope separation factors obtained decreased by increasing the temperature, and the factors for macroreticular resins were identical with those for the usual gel-type resins. However, the performance of isotope separation per unit band length in displacement chromatography was found to be improved by increasing the temperature and using macroreticular resins, because accelerating the interphase mass transfer caused the reduction of HETP (Height Equivalent to a Theoretical Plate).

1983-01-01

176

Complex radiation degradation behaviour of PVC materials under accelerated aging conditions  

International Nuclear Information System (INIS)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the levelling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests. (author).

1982-10-01

177

Complex radiation degradation behavior of PVC materials under accelerated aging conditions  

Energy Technology Data Exchange (ETDEWEB)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the leveling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests.

1983-07-01

178

An ELISA-based high throughput protein truncation test for inherited breast cancer  

Science.gov (United States)

IntroductionBreast cancer is the most diagnosed and second leading cause of cancer deaths in the U.S. female population. An estimated 5 to 10 percent of all breast cancers are inherited, caused by mutations in the breast cancer susceptibility genes (BRCA1/2). As many as 90% of all mutations are nonsense mutations, causing a truncated polypeptide product. A popular and low cost method of mutation detection has been the protein truncation test (PTT), where target regions of BRCA1/2 are PCR amplified, transcribed/translated in a cell-free protein synthesis system and analyzed for truncated polypeptides by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and autoradiography. We previously reported a novel High Throughput Solid-Phase PTT (HTS-PTT) based on an enzyme-linked immunosorbent assay (ELISA) format that eliminates the need for radioactivity, SDS-PAGE and subjective interpretation of the results. Here, we report the next generation HTS-PTT ...

2010-10-04

179

Ambient Air Radionuclide Concentrations at and near TA-50 from 2003 through the First Quarter of 2004  

Energy Technology Data Exchange (ETDEWEB)

The Meteorology and Air Quality (MAQ) group at Los Alamos National Laboratory maintains and operates a large network of environmental air samplers called AIRNET. Some of these samplers are located near Material Disposal Area C at TA-50, a low-level radioactive waste burial site in the semiarid environment of the Pajarito Plateau, near Los Alamos. AIRNET sampling media consist of a filter and silica gel. They are exchanged once every 2 weeks. Presented are 5 months of air sampling results for 5 stations operating in the vicinity of Material Disposal Area C.

2005-09-05

180

Aluminium, gallium and indium complexing with methylthymol blue  

International Nuclear Information System (INIS)

Al, Ga and In complexing with methylthymol blue (H_6R) purified by gel filtration is studied. in the case of metal excess complexes with the ratio of components M:H_6R=2:1 with #lambda#=587(Al), 590(Ga) and 593 nm(In) appear. In the case of reacting agent excess complexes with the ratio of component 1:1 with #lambda#_m_a_x=480-490 (Al) and 480 nm(Ga, In) appear. The mechanism of complexing reactions is studied. Molar extinction coefficients and stability constants are calculated.

1988-01-01

181

Sol-gel-immobilized Tris(2,2'-bipyridyl)ruthenium(II) electrogenerated chemiluminescence sensor for high-performance liquid chromatography  

International Nuclear Information System (INIS)

The sol-gel-immobilized Tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy)_3 "2"+] electrogenerated chemiluminescence (ECL) sensor was applied to the reversed-phase high-performance liquid chromatography (HPLC) determination of phenothiazine derivatives (promazine, chlorpromazine, triflupromazine, thioridazine, and trifluoperazine) and erythromycin in human urine samples. In this method, Ru(bpy)_3 "2"+ was immobilized in sol-gel-derived titania (TiO_2)-Nafion nanocomposite films coated on a dual platinum electrode. This method eliminates an extra pump needed for the delivery of Ru(bpy)_3 "2"+ reagent into a reaction/observation zone in front of photomultiplier tube because the immobilized-Ru(bpy)_3 "2"+ is recycled on the electrode surface by an applied potential at +1.3 V versus Ag/AgCl (3 M NaCl) reference electrode. The resulting analytical performances such as detection limit, working range, sensitivity, and measurement precision were slightly ...

2005-06-13

182

Sol-gel-immobilized Tris(2,2'-bipyridyl)ruthenium(II) electrogenerated chemiluminescence sensor for high-performance liquid chromatography  

Energy Technology Data Exchange (ETDEWEB)

The sol-gel-immobilized Tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy){sub 3} {sup 2+}] electrogenerated chemiluminescence (ECL) sensor was applied to the reversed-phase high-performance liquid chromatography (HPLC) determination of phenothiazine derivatives (promazine, chlorpromazine, triflupromazine, thioridazine, and trifluoperazine) and erythromycin in human urine samples. In this method, Ru(bpy){sub 3} {sup 2+} was immobilized in sol-gel-derived titania (TiO{sub 2})-Nafion nanocomposite films coated on a dual platinum electrode. This method eliminates an extra pump needed for the delivery of Ru(bpy){sub 3} {sup 2+} reagent into a reaction/observation zone in front of photomultiplier tube because the immobilized-Ru(bpy){sub 3} {sup 2+} is recycled on the electrode surface by an applied potential at +1.3 V versus Ag/AgCl (3 M NaCl) reference electrode. The resulting analytical performances such as detection limit, working range, ...

2005-06-13

183

Research efforts to produce a {sup 99}Mo-{sup 99m}Tc generator using reactor-produced {sup 99}Mo  

Energy Technology Data Exchange (ETDEWEB)

Recognizing the importance of {sup 99m}Tc and {sup 99m}Tc-based radiopharmaceuticals in nuclear medicine, the Philippine Nuclear Research Institute has initiated research on the development of column-type generators for {sup 99m}Tc using {sup 99}Mo in the form of a gel. The use of reactor-produced {sup 99}Mo will reduce the country's dependence on the importation of commercial generators based on fission product molybdenum-99. However, the relatively low specific activity of {sup 99}Mo must be compensated by the high adsorption capacity of the column material for molybdenum. A procedure based on the incorporation of low activity {sup 99}Mo into a zirconium molybdate gel matrix was adopted with reasonable success. Because the properties of the gel vary considerably with conditions of synthesis, the following parameters were carefully controlled: pH, concentration, temperature, order of mixing of the reactant ...

2003-03-01

184

Rare-earth mixed oxide thin films as 100% lattice match buffer layers for YBa2Cu3O7-x coated conductors  

International Nuclear Information System (INIS)

Buffer layers with 100% lattice match with YBa2Cu3O7 - ? (YBCO) were prepared from mixed rare-earth-oxides applying a simple sol-gel process and dip-coating method. Structural analysis of the sol-gel derived powder by X-ray diffraction revealed that the mixing parameter, which eliminates the lattice mismatch with YBCO, is x = 0.2382, 0.1852, 0.1252, 0.0906, 0.0793 and 0.0395 in (Eu1 - xHox)2O3, (Eu1 - xErx)2O3, (Eu1 - xYbx)2O3, (Gd1 - xHox)2O3, (Gd1 - xYx)2O3 and (Gd1 - xYbx)2O3, respectively. Microstructural investigations were carried out for Gd1.819Ho0.181O3 films epitaxially grown on cube-textured Ni (100) substrates by sol-gel dip-coating process. X-ray diffraction of the buffer showed strong out-of-plane orientation on Ni tape. The (Gd1 - xHox)2O3 (222) pole figure indicated a single cube-on-cube textured structure. The omega and phi scans revealed good out-of-plane and in-plane alne alignments. The full-width at ...

2010-04-02

185

Nonaqueous synthesis of metal oxide nanoparticles: Short review and doped titanium dioxide as case study for the preparation of transition metal-doped oxide nanoparticles  

Science.gov (United States)

The liquid-phase synthesis of metal oxide nanoparticles in organic solvents under exclusion of water is nowadays a well-established alternative to aqueous sol-gel chemistry. In this article, we highlight some of the advantages of these routes based on selected examples. The first part reviews some recent developments in the synthesis of ternary metal oxide nanoparticles by surfactant-free nonaqueous sol-gel routes, followed by the discussion of the morphology-controlled synthesis of lanthanum hydroxide nanoparticles, and the presentation of structural peculiarities of manganese oxide nanoparticles with an ordered Mn vacancy superstructure. These examples show that nonaqueous systems, on the one hand, allow the preparation of compositionally complex oxides, and, on the other hand, make use of the organic components (initially present or formed in situ) in the reaction mixture to tailor the morphology. Furthermore, obviously even the crystal ...

2008-07-15

186

Nanoparticle arrays formed by spatial compartmentalization in a complex fluid.  

Energy Technology Data Exchange (ETDEWEB)

A mesoscopically ordered lamellar gel phase of a polymer-grafted, lipid-based complex fluid is used as a scaffolding to spatially organize inorganic nanoparticles. The complex fluid provides both a highly anisotropic environment and a segregated aqueous and organic domains in which inorganic nanoparticles can be selectively placed by tailoring their size and surface characteristics. Three types of silver nanoparticles -- underivatized, surfactant-stabilized, and dodecanthiol-derivatized -- were evaluated. Comparison of the surface plasmon resonance of the various silver particles dispersed in conventional solvents to those contained within the complex fluid was used to determine the region of spatial localization in the lamellar gel phase. Silver particles rendered hydrophobic by capping with an alkane thiol insert into the hydrocarbon bilayer region. Surfactant-stabilized and underivatized silver nanoparticles reside in the aqueous channels, ...

2001-03-14

187

Liver Zn-thionein (ZnMT) regulates the interaction of Zn and Pb with delta-aminolevulinic acid dehydratase (ALAD)  

Energy Technology Data Exchange (ETDEWEB)

ZnMT has been postulated to function in essential metal homeostasis and metal detoxication. This study was undertaken to evaluate the potential of liver ZnMT to mediate the interaction of Zn and Pb with the Zn metalloenzyme, ALAD. Pretreatment of rats with Zn activated liver ALAD and attenuated the inhibition of ALAD by Pb in vitro and in vivo. Liver cytosol from Zn-pretreated rats injected with /sup 203/Pb was fractionated via gel filtration and anion-exchange chromatography and disclosed that both Zn and /sup 203/Pb co-eluted in the MT fractions. Both purified ZnMT-I and ZnMT-II bound /sup 203/Pb in vitro as shown by gel filtration chromatography. Addition of purified liver ZnMT to purified bovine liver ALAD reaction mixtures increased enzyme activity by 2-fold and prevented inhibition of ALAD by Pb. Addition of apothionein alone decreased the activity of Zn-activated ALAD and also attenuated Pb inhibition of the enzyme. ...

1987-05-01

188

Detection by cationized /sup 125/I-cytochrome C of proteoglycans (PG) transferred to nylon  

Energy Technology Data Exchange (ETDEWEB)

Cytochrome c, labeled with /sup 125/I, has been used by us for staining glycosaminoglycans (GAG) separated by electrophoresis on cellulose acetate strips. As GAG between 1-10 ng could be quantified by autoradiography and densitometry, the reagent is approximately 100-fold more sensitive than currently used non-radiolabeled stains. The authors extend now the use of radiolabeled cytochrome c to the quantification of PG transblotted to solid supports subsequent to separation on polyacrylamine slab gels. Dot blotting used for exploring optimal conditions for detecting PG indicated that because of low background positively charged Nylon 66 was superior to nitrocellulose. Increasing the positive charge of the staining reagent by cationization decreased background radiation even further so that 1 ng PG could be seen readily after 5 hrs of autoradiography. Use of cationized /sup 125/I-cytochrome c has been made in detecting PG of bovine fetal epiphyseal cartilage (> 1 x ...

1986-05-01

189

Comparative study of polymer matrices for gelled electrolytes of lithium batteries; Etude comparative de matrices polymeres pour electrolytes gelifies de batteries au lithium  

Energy Technology Data Exchange (ETDEWEB)

A solid electrolyte for lithium batteries requires several properties: a good ionic conductivity of about 10{sup -3} S/cm at 298 deg. K, a high cationic transport number (greater than 0.5), a redox stability window higher than 4.5 V, a good stability of the interface with the lithium electrode, and a sufficient mechanical stability. The family of gelled or hybrid electrolytes seems to meet all these requirements. Thus, a systematic study of the gelling of an ethylene carbonate and lithium bistrifluorosulfonimide (LiTFSI) based electrolyte has been carried out. The polymers used for gel or pseudo-gel synthesis are POE, PMMA and PAN which represent 3 different cases of interaction with the electrolyte. All the properties mentioned above have been studied according to the nature of the polymer and to the concentration of lithium salt, showing the advantages and drawbacks of each polymer. The possibility of using some of these ...

1996-12-31

195

Obtainment of lanthanum oxide by fractionated precipitation method  

International Nuclear Information System (INIS)

... ammonium compounds benzilic acid chemical preparation lanthanum oxides

1979-01-01

198

Interaction of silicides in the Pd - Mo - Si ternary system  

International Nuclear Information System (INIS)

... chemical reactions high temperature lattice parameters microhardness

199

Inorganic chemistry of astatine  

International Nuclear Information System (INIS)

On the basis of experimental and extrapolated values the physico-chemical properties of astatine are reviewed considering all oxidation states.

209

Breath Test for Chemicals (Volatile Organic Compounds)  

Science.gov (United States)

Breath Tests; Human Volunteers; Pilot Study

2011-09-16

211

An R&D Exploratory Investigation of Resin Binders for the ...  

Science.gov (United States)

... Descriptors : *POLYMERS, *BINDERS, *HOWITZERS, *COMBUSTIBLE CARTRIDGE CASES, CHEMICAL COMPOSITION, PROPELLING ...

1980-10-01

213

Contamination and restoration of groundwater aquifers  

Energy Technology Data Exchange (ETDEWEB)

Humans are exposed to chemicals in contaminated groundwaters that are used as sources of drinking water. Chemicals contaminate groundwater resources as a result of waste disposal methods for toxic chemicals, overuse of agricultural chemicals, and leakage of chemicals into the subsurface from buried tanks used to hold fluid chemicals and fuels. In the process, both the solid portions of the subsurface and the groundwaters that flow through these porous structures have become contaminated. Restoring these aquifers and minimizing human exposure to the parent chemicals and their degradation products will require the identification of suitable biomarkers of human exposure; better understandings of how exposure can be related to disease outcome; better understandings of mechanisms of transport of pollutants in the heterogeneous structures of the ...

1993-04-01

214

Investigation of the potential influence of production treatment chemicals on produced water toxicity  

International Nuclear Information System (INIS)

Production treatment chemicals represent a diverse collection of chemical classes, added at various points from the wellhead to the final flotation cell, to prevent operational upsets and enhance the separation of oil from water. Information in the literature indicates that while many treatment chemicals are thought to partition into oil and not into the produced water, there are cases where a sufficiently water soluble treatment chemical is added at high enough concentrations to suggest that the treatment chemical may add to the aquatic toxicity of the produced water. A study was conducted to evaluate the potential effect of production treatment chemicals on the toxicity of produced waters using the US EPA Seven-day Mysidopsis bahia Survival, Growth and Fecundity Test. Samples of produced water were collected and tested for toxicity from three platforms under ...

1993-11-14

215

The chemical link Brazil/Portugal. Abstracts of the 23. annual meeting of the Brazilian Chemical Society. v. 2; A ligacao quimica Brasil/Portugal. Resumos da 23. reuniao anual da Sociedade Brasileira de Quimica. v. 2  

Energy Technology Data Exchange (ETDEWEB)

Several works about annual meeting of the Brazilian Chemical Society are present.The search for medicinal chemistry, natural products, biological chemistry, and organic chemistry are shown. Conventional methods and some techniques are discussed and developments of new methods of determining are studied. The use of new chemical compounds, materials, structures and chemical analysis are shown.

2000-07-01

216

Technological press on the environment: comparison of the radiation and conventional processing  

International Nuclear Information System (INIS)

Transformation of row material to the consumption goods proceeds by the succession of various technologies using energy and chemicals. Relative contribution of both factors is broadly varied. The chemical reagents are not per se consumption goods and their production is auxiliary. Maximal usage of chemicals is observed in conventional technologies. On the contrary radiation technology does not need chemicals. Therefore usage of radiation technology leads to diminution of chemical processing and hence to the attenuation of the technological press on the environment. As examples the radiation technological methods in conversion of coal and biomass are considered. (author).

1994-09-11

217

The application of computer modeling to health effect research  

Energy Technology Data Exchange (ETDEWEB)

In the United States, estimates show that more than 30,000 hazardous waste disposal sites exist, not including military installations, U.S. Department of Energy nuclear facilities, and hundreds and thousands of underground fuel storage tanks; these sites undoubtedly have their own respective hazardous waste chemical problems. When so many sites contain hazardous chemicals, how does one study the health effects of the chemicals at these sites? There could be many different answers, but none would be perfect. For an area as complex and difficult as the study of chemical mixtures associated with hazardous waste disposal sites, there are no perfect approaches and protocols. Human exposure to chemicals, be it environmental or occupational, is rarely, if ever, limited to a single chemical. Therefore, it is essential that we consider multiple ...

1996-12-31

218

Sources of toxicity and exposure information for identifying chemicals of high concern to children  

International Nuclear Information System (INIS)

Due to the large number of chemicals in commerce without adequate toxicity characterization data, coupled with an ineffective federal policy for chemical management in the United States, many states are grappling with the challenge to identify toxic chemicals that may pose a risk to human health and the environment. Specific populations (e.g., children, elderly) are particularly sensitive to these toxic chemicals. In 2008, the Children's Safe Product Act (CSPA) was passed in Washington State. The CSPA included specific requirements to identify High Priority Chemicals (HPCs) and Chemicals of High Concern to Children (CHCCs). To implement this legislation, a methodology was developed to identify HPCs from authoritative scientific and regulatory sources on the basis of toxicity criteria. Another set of chemicals of concern was then identified ...

2010-11-01

219

Supplier notification requirements under section 313 of the Emergency Planning and Community Right-to-Know Act (1991)  

International Nuclear Information System (INIS)

When Congress passed the Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA), it created a number of new reporting requirements for companies that handle toxic chemicals and products containing toxic chemicals. Section 313 of EPCRA requires that certain manufacturers report annual releases to the environment of listed toxic chemicals and chemical categories. Because these manufacturers must know the toxic chemical composition of the products they use to be able to calculate releases accurately, EPA requires some suppliers of mixtures or trade name products containing one or more of the listed section 313 toxic chemicals to notify their customers. The pamphlet explains which suppliers must notify their customers, who must be notified, what form the notice must take, and when it must be sent.

220

Cumulative effects of in utero administration of mixtures of reproductive toxicants that disrupt common target tissues via diverse mechanisms of toxicity  

British Library Electronic Table of Contents (United Kingdom)

Summary Although risk assessments are typically conducted on a chemical-by-chemical basis, the 1996 Food Quality Protection Act required the US Environmental Protection Agency to consider cumulative risk of chemicals that act via a common mechanism of toxicity. To this end, we are conducting studies with mixtures of chemicals to elucidate mechanisms of joint action at the systemic level with the goal of providing a framework for assessing the cumulative effects of reproductive toxicants. Previous mixture studies conducted with antiandrogenic chemicals are reviewed briefly and two new studies are described. In all binary mixture studies, rats were dosed during pregnancy with chemicals, singly or in pairs, at dosage levels equivalent to approximately one-half of the ED50 for hypospadias or e...

2010-01-01

221

Biocide and corrosion inhibition use in the oil and gas industry: Effectiveness and potential environmental impacts  

International Nuclear Information System (INIS)

Treatment chemicals are used in all facets of the natural gas industry (NGI) from well development through transmission and storage of natural gas. The multitude of chemicals used, combined with the dozens of chemical manufacturers and/or suppliers has lead to the availability of hundreds of possible chemical products. Because of the widespread use of chemical products and their numerous sources, the NGI needs access to consistent data regarding their effectiveness and potential environmental impacts. The objective of this work was to evaluate the effectiveness and potential environmental impacts of, chemical products used in the NGI. This assessment was initially focused on biocides and corrosion inhibitors and their use in the gas production, storage and transmission facilities, The overall approach was obtain the necessary data on ...

1995-03-27

222

Vacuolar/Extravacuolar Distribution of Aminopeptidases in Giant Alga Chara australis and Partial Purification of One Such Enzyme 1  

Science.gov (United States)

The presence of two major aminopeptidases (aminopeptidases I and II) in the giant alga Chara australis was shown using polyacrylamide gel electrophoresis. Partially purified aminopeptidase I had a molecular weight of about 120,000, hydrolyzed both leucine-?-naphthylamide (pH optimum 6.0) and alanine-?-naphthylamide (pH optimum 7.5), and was located both inside and outside the vacuole. Aminopeptidase I was inhibited by p-chloromercuribenzoic acid, iodoacetic acid, 1,10-phenanthroline, and N-tosyl-l-phenylalanine chloromethyl ketone. Aminopeptidase II hydrolyzed alanine-?-naphthylamide but not leucine-?-naphthylamide and was located only outside the vacuole.ImagesFig. 1Fig. 2Fig. 4Fig. 5

1987-01-01

223

UV-induced switching behavior of novel fluoroalkyl end-capped vinyltrimethoxysilane oligomer/titanium oxide nanocomposite between superhydrophobicity and superhydrophilicity with good oleophobicity  

British Library Electronic Table of Contents (United Kingdom)

Fluoroalkyl end-capped vinyltrimethoxysilane oligomer suffered the sol-gel reaction under alkaline conditions in the presence of titanium oxide nanoparticles in tetrahydrofuran to afford the corresponding fluorinated oligomer/titanium oxide nanocomposites[RF-(VM-SiO2)n-RF/TiO2] in excellent to moderate isolated yields. These fluorinated composites thus obtained were nanometer size-controlled fine particles, and exhibited good dispersibility and stability in traditional organic solvents except for water. These fluorinated nanocomposites were applied to the surface modification of glass to exhibit not only a completely superhydrophobic characteristic (a water contact angle: 180degree) with a non-wetting property against water droplets but also a good oleophobicity imparted by fluoroalkyl seg...

2010-01-01

224

Synthesis of reversible fluorescent organogel containing 2-(2prime-hydroxyphenyl)benzoxazole: fluorescence enhancement upon gelation and detecting property for nerve gas simulant  

British Library Electronic Table of Contents (United Kingdom)

A new low molecular mass organogelator 1 containing 2-(2prime-hydroxyphenyl)benzoxazole (HPB) group with long alkyl chain was synthesized by the reaction with 5-amino-2-(2prime-hydroxy-4prime-methylphenyl)benzoxazole and dodecyl isocyanate in THF at room temperature. The reversible gelation ability of 1 was investigated using a heating-cooling method in various organic solvents. The stable organogel was formed from carbon tetrachloride or from cyclohexane at the concentration as low as 0.9%. The self-assembled supramolecular gel structure formed by non-covalent bonding was confirmed with field emission-scanning electron microscope (FE-SEM) exhibiting fibril- or ribbon-shaped structure depending on the solvent used. Regarding the aggregation-induced emission enhancement (AIEE) phenomenon, t...

2010-01-01

225

Synthesis of C-11 iodoantipyrine for positron emission tomography  

Energy Technology Data Exchange (ETDEWEB)

We have developed a method for the synthesis of C-11 iodoantipyrine. Carbon-11-labeled methyl iodide, prepared from /sup 11/CO2, was used to methylate 3-methyl-1-phenyl-2-pyrazolin-5-one to form C-11 antipyrine. Following silica-gel column chromatography and iodination, radiochemical purity of the C-11 iodoantipyrine was more than 99.5%, with a 10% yield and a specific activity of 30 mCi/mumol. Preliminary animal studies showed complete cerebral extraction and local cerebral blood-flow values that were within 4.6% of those obtained using C-14 iodoantipyrine. The C-11 analog, with positron emission tomography, will facilitate local cerebral blood-flow studies in human subjects.

1981-06-01

226

Studies of human mutation rates  

Energy Technology Data Exchange (ETDEWEB)

November 1989, marked the beginning of a new three-year cycle of DOE grant support, in connection with which the program underwent a major reorganization. This document presents the progress on the three objectives of the present program which are: to isolate by the technique of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), proteins of special interest because of the relative mutability of the corresponding gene, establish the identity of the protein, and, for selected proteins, move to a characterization of the corresponding gene; to develop a more efficient approach, based on 2-D PAGE, for the detection of variants in DNA, with special reference to the identification of mutations in the parents of the individual whose DNA is being examined; and, to continue an effective interface with the genetic studies on the children of atomic bomb survivors in Japan, with reference to both the planning and implementation of new studies at the molecular level.

1990-01-01

227

Species and Organ Diversity in the Effects of Hydrogen Peroxide on Superoxide Dismutase Activity In Vitro  

British Library Electronic Table of Contents (United Kingdom)

Abstract Superoxide dismutase (SOD) is ubiquitous in aerobic organisms and constitutes the first link in the enzyme scavenging system of reactive oxygen species. In the present study, species and organ diversity of SOD activity in a solution and in an in-gel assay system, as well as the effects of hydrogen peroxide (H2O2) on SOD activity, were investigated. In a solution assay system, SOD activity of jackfruit root, shoot, leaves, axes, and cotyledons, of maize embryos and endosperms, of mung bean leaves and seeds, of sacred lotus axes and cotyledons, and of rice and wheat leaves was increased by 1-15 mmol/L H2 O2. However, SOD activity in rice root and seeds, maize roots and leaves, mung bean roots and shoots, and wheat seeds was decreased by 1-15 mmol/L H2O2. The SOD activity of wheat ro...

2006-01-01

228

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

British Library Electronic Table of Contents (United Kingdom)

Summary: 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 res...

2006-01-01

229

Selective oxidations on vanadiumoxide containing amorphous mixed oxides (AMM-V) with tert.-butylhydroperoxide  

Energy Technology Data Exchange (ETDEWEB)

The catalytic oxygen transfer properties of vanadium containing zeolites and vanadium based sol-gel catalysts with hydrogen peroxides are well known. The severe problem of vanadium leaching caused by the presence of the by-product water has been addressed. To avoid any interference with homogeneously catalyzed reactions, our study focusses on selective oxidations in a moisture-free medium with tert.-butylhydroperoxide. We have investigated the catalytic properties of amorphous microporous materials based on SiO{sub 2}, TiO{sub 2}, ZrO{sub 2} and Al{sub 2}O{sub 3} as matrix material and studied the effects of surface polarity on the oxidation of 1-octene and cyclohexane. (orig.)

1998-12-31

230

Programmed cell death during pigment gland formation in Gossypium hirsutum leaves  

British Library Electronic Table of Contents (United Kingdom)

Abstract Ultrastructural studies have shown that the formation of pigment glands in Gossypium hirsutum L. leaves is a lysigenous process, originating from a cluster of cells in the ground meristem. Various techniques were used here to investigate whether programmed cell death (PCD) plays a critical role in this developmental process. Nuclei of internal cells in the pigment gland-forming tissue were TUNEL-positive and DAPI-negative, suggesting that DNA cleavage is an early event and complete DNA degradation is a late event. Smeared bands and a lack of laddering after gel electrophoresis indicate that DNA cleavage is random. Ultrastructurally, secretory cells in the pigment glands become distorted, nuclei are densely stained, and chromosomes become condensed until completely degraded at late...

2010-01-01

231

Powder characteristics and microstructure of uranium dioxide and uranium dioxide-gadolinium oxide fuel  

Energy Technology Data Exchange (ETDEWEB)

Three different fuels UO{sub 2}-only, UO{sub 2}-Gd{sub 2}O{sub 3}(5%), and UO{sub 2}-Gd{sub 2}O{sub 3}(10%) were produced by sol-gel technique. Their powder characteristics such as flowability, BET surface area, average pore diameter, and cumulative pore volume were determined. The pore size distributions of powders, green pellets, and sintered fuels were determined by using a mercury porosimeter. The theoretical densities of sintered fuels were found to be 98.01, 95.3, and 95.9 %, respectively. Their ruggedness fractal dimensions were 1.111, 1.044, and 1.042, while the fractal dimensions associated with the size distribution of grains were 1.44, 1.58, and 1.60, respectively. (orig.).

1996-07-01

232

National technical report (Matsushita Electric Industrial Company), Vol. 40, No. 4, August 1994. Special issue on batteries  

Energy Technology Data Exchange (ETDEWEB)

Contents: recent trend of battery technologies; alkaline manganese battery with no mercury addition; high capacity zinc-air battery series for hearing aids; characteristics of vanadium-niobium-lithium rechargeable battery; high-energy density lithium-ion rechargeable battery; lithium polymer rechargeable battery: polymer gel electrolyte and electrode; high-capacity ni-cd battery sm120; high-capacity nickel-metal hydride battery; sealed-type batteries for electric vehicles; high-temperature-durable calcium-type battery for automobiles; sealed lead acid batteries for upss; solar cell power unit; solid oxide fuel cell (1); battery management system.

1994-08-01

233

Methanogen community structure in the rumens of farmed sheep, cattle and red deer fed different diets  

British Library Electronic Table of Contents (United Kingdom)

Abstract Development of inhibitors and vaccines that mitigate rumen-derived methane by targeting methanogens relies on knowledge of the methanogens present. We investigated the composition of archaeal communities in the rumens of farmed sheep (Ovis aries), cattle (Bos taurus) and red deer (Cervus elaphus) using denaturing gradient gel electrophoresis (DGGE) to generate fingerprints of archaeal 16S rRNA genes. The total archaeal communities were relatively constant across species and diets, and were less variable and less diverse than bacterial communities. There were diet- and ruminant-species-based differences in archaeal community structure, but the same dominant archaea were present in all rumens. These were members of three coherent clades: species related to Methanobrevibacter ruminan...

2011-01-01

234

Malignant transformation of diploid human fibroblasts by transfection of oncogenes  

Energy Technology Data Exchange (ETDEWEB)

This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy.

1992-01-01

235

Low-temperature oxidative degradation of PBX 9501 and its components determined via molecular weight analysis of the Poly[ester urethane] binder  

British Library Electronic Table of Contents (United Kingdom)

The results of following the oxidative degradation of a plastic-bonded explosive (PBX 9501) are reported. Into over 1100 sealed containers were placed samples of PBX 9501 and combinations of its components and aged at relatively low temperatures to induce oxidative degradation of the samples. One of the components of the explosive is a poly(ester urethane) polymer and the oxidative degradation of the samples were following by measuring the molecular weight change of the polymer by gel permeation chromatography (coupled with both differential refractive index and multiangle laser light scattering detectors). Multiple temperatures between 40 and 64 degreeC were used to accelerate the aging of the samples. Interesting induction period behavior, along with both molecular weight increasing (cro...

2009-01-01

236

Lithium carbon batteries with solid polymer electrolyte; Accumulateur lithium carbone a electrolyte solide polymere  

Energy Technology Data Exchange (ETDEWEB)

The lithium carbon batteries studied in this paper use plasticized polymer electrolytes made with passive polymer matrix swollen by a liquid electrolyte with a high ionic conductivity (> 10{sup -3} S/cm at 25 deg. C). The polymers used to prepare the gels are polyacrylonitrile (PAN) and vinylidene poly-fluoride (PVdF). The electrochemical and physical properties of these materials are analyzed according to their composition. The behaviour of solid electrolytes with different materials of lithium ion insertion (graphite and LiNiO{sub 2}) are studied and compared to liquid electrolytes. The parameters taken into account are the reversible and irreversible capacities, the cycling performance and the admissible current densities. Finally, complete lithium ion batteries with gelled electrolytes were manufactured and tested. (J.S.) 2 refs.

1996-12-31

237

Irradiation of polyethylene in the presence of antioxidants  

International Nuclear Information System (INIS)

The radiation induced reactions in LDPE in the presence of phenolic type antioxidants have been studied. It was shown that various antioxidants can influence the polyethylene network formation and the radical yield in different ways. The dependence of network structure on absorbed doses was determined by gel analysis, hot-set test and extraction of antioxidants for samples irradiated with accelerated electrons. It was found that the antioxidants eluted from polyethylene in higher percentage influence polymer crosslinking to a smaller degree. The ESR studies of #gamma#-irradiated blends of polyethylene with antioxidant indicate the presence of alkyl and phenoxyl radicals. The role of antioxidant molecules on radiation induced reactions in polyethylene-antioxidant systems is considered. The correlation between the network structure and the type of additive in polyethylene is also discussed. (author).

238

Intravaginal immunization using the recombinant HIV-1 clade-C trimeric envelope glycoprotein CN54gp140 formulated within lyophilized solid dosage forms  

British Library Electronic Table of Contents (United Kingdom)

Vaccine-mediated prevention of primary HIV-1 infection at the heterosexual mucosal portal of entry may be facilitated by highly optimised formulations or drug delivery devices for intravaginal (i.vag) immunization. Previously we described hydroxyethylcellulose (HEC)-based rheologically structured gel vehicles (RSVs) for vaginal immunization of an HIV-1 vaccine candidate, a soluble recombinant trimeric HIV-1 clade-C envelope glycoprotein designated CN54gp140. Here we investigated the efficacy of lyophilized solid dosage formulations (LSDFs) for prolonging antigen stability and as i.vag delivery modalities. LSDFs were designed and developed that upon i.vag administration they would reconstitute with the imbibing of vaginal fluid to mucoadhesive, site-retentive semi-solids. Mice were immunize...

2011-01-01

239

Humectant. Hoshitsuzai  

Energy Technology Data Exchange (ETDEWEB)

This paper elucidates the effect of humectant performance on the wettability of the skin. Humectants are divided into the organic compounds, such as polyols, the organometallic compounds, such as sodium lactate and pyrolidone sodium carboxylate, and the water soluble high molecular compounds, such as polyethylene glycol and hyaluronic acid. Firstly, hygroscopic performances and characteristics of various hcmectants are illustrated. Then, the humectant performance of the skin and relation between amino acid in the horny layer and moisture content are described. The humectant performance possessed in the intercellular lipid of horny layer is also described. Furthermore, are explained the wettability of the skin by cosmetics and the role of humectant as an emulsifying assistant. A mechanism of the dry skin, improvement effect of the skin by humectants, and combining effect of the humectants are presented. Are also presented the nonaqueous emulsification, amino acid ...

1993-06-20

240

Gas chromatography - mass-spectrometry of volatiles released from plastics used as building materials  

Energy Technology Data Exchange (ETDEWEB)

The possibility of employing a number of adsorbents (polyphenylquinoxaline, Tenax GC, Carbopak C, graphitized thermal carbon black, silica gels modified with pyrocarbon or hexamethyldisilazane) for the trapping of organic traces from air has been investigated. Adsorption capacities of these adsorbents with respect to a number of volatiles released from certain plastics used as building material (polyvinylchloride, Relin, Acronal, etc.) have been measured. A number of the volatiles were identified by gas chromatography - mass-spectrometry after trapping on the adsorbents investigated. Chromatographic separation after trapping on the adsorbents was carried out on wall-coated open-tubular capillary columns as well as in capillary columns packed with graphitized thermal carbon black.

1983-10-01

241

Functional adaptation of microbial communities from jet fuel-contaminated soil under bioremediation treatment: simulation of pollutant rebound  

British Library Electronic Table of Contents (United Kingdom)

Abstract To investigate the link between the functionality and the diversity of microbial communities under strong selective pressure from pollutants, two types of mesocosms that simulate natural attenuation and phytoremediation were generated using soil from a site highly contaminated with jet fuel and under air-sparging treatment. An increase in the petroleum hydrocarbon concentration from 4900 to 18-500-mg-kg-1-dw soil simulated a pollutant rebound (postremediation pollutant reversal due to residual contamination). Analysis of soil bacterial communities by denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments showed stronger changes and selection for a phylogenetically diverse microbial population in the mesocosms with pollutant-tolerant willow trees. Enumerat...

2011-01-01

242

Evaluation of a commercial MRSA assay when multiple MRSA strains are causing epidemics  

British Library Electronic Table of Contents (United Kingdom)

Rapid and reliable diagnostic methods are needed to control methicillin-resistant Staphylococcus aureus (MRSA) transmission. We studied the BD GeneOhm? MRSA Assay which is based on one specific amplification product at the junction of the right extremity sequence of the staphylococcal cassette chromosome mec (SCCmec) and the chromosomal sequence of orfX of S. aureus. The test was applied on 95 clinical isolates in Finland: 83% were positive. The isolates giving negative results represented several pulsed-field gel electrophoresis (PFGE) types and harboured SCCmec types IV, V, VI or were new types with different combinations of ccr genes.

2009-01-01

243

Cholera toxin can catalyze ADP-ribosylation of cytoskeletal proteins  

International Nuclear Information System (INIS)

Cholera toxin catalyzes transfer of radiolabel from ["3"2P]NAD"+ to several peptides in particulate preparations of human foreskin fibroblasts. Resolution of these peptides by two-dimensional gel electrophoresis allowed identification of two peptides of M/sub r/ = 42,000 and 52,000 as peptide subunits of a regulatory component of adenylate cyclase. The radiolabeling of another group of peptides (M/sub r/ = 50,000 to 65,000) suggested that cholera toxin could catalyze ADP-ribosylation of cytoskeletal proteins. This suggestion was confirmed by showing that incubation with cholera toxin and ["3"2P]NAD"+ caused radiolabeling of purified microtubule and intermediate filament proteins.

1981-01-01

244

Chitinolytic enzyme production and genetic improvement of a new isolate belonging to Streptomyces anulatus  

British Library Electronic Table of Contents (United Kingdom)

Thirty bacterial isolates were obtained from different sources and sites at Jeddah, Saudi Arabia, on chitin agar medium; 9 of the 30 isolates were cultured in liquid medium containing chitin as sole carbon and nitrogen sources. Isolate SM21, which was isolated from shrimp shells, showed the best growth and chitinase production in liquid medium. According to its morphological, physiological and biochemical characteristics, SM21 belongs to the genus Streptomyces and was identified as Streptomyces anulatus SM21. Identification was confirmed using 16S rDNA analysis. The chitinase enzyme was precipitated with 80% NH4SO4 and purified using DEAE-cellulose ion exchange chromatography followed by Sephadex G-100 gel filtration. The molecular weight determined using sodium dodecyl sulfate polyacrylam...

2011-01-01

245

Chemistry between crosslinks affects the properties of peptide hydrogels  

British Library Electronic Table of Contents (United Kingdom)

Protein hydrogels were prepared by substituting ovalbumin with different concentrations of ethyl vinyl sulfone (EVS) or acrylic acid (AA) and crosslinking with divinyl sulfone (DVS). Fourier transform-infrared (FT-IR) spectroscopic studies confirmed the addition of EVS, AA, and DVS onto the protein. Swelling was assessed as a function of pH in the range of 2.5 to 9.4 and ionic strength. The elastic modulus of the gels was determined in shear and compression. Stress relaxation was assessed in compression. The substituent highly affected swelling and modulus with both hydrogels displaying non-Gaussian behavior in the range of hydrogel environments studied. Acrylic acid substituted ovalbumin exhibited a decreasing modulus with increasing swelling behaving as a polyelectrolyte with low added s...

2011-01-01

246

5. Sampling  

International Nuclear Information System (INIS)

The sampling is described for radionuclide X-ray fluorescence analysis. Aerosols are captured with various filter materials whose properties are summed up in the table. Fine dispersed solid and liquid particles and gaseous admixtures may be captured by bubbling air through a suitable absorption solution. The concentration of small amounts of impurities from large volumes of air is done by adsorbing impurities on surfactants, e.g., activated charcoal, silica gel, etc. Aerosols may be captured using an electrostatic precipitator and aerosol fractions may be separated with a cascade impactor. Water sampling differs by the water source, i.e., ground water, surface water, rain or waste water. Soil samples are taken by probes. (ES).

1983-12-01

247

Theory of chemical reaction dynamics. Volume 3  

Energy Technology Data Exchange (ETDEWEB)

This book examines some of the basic principles behind chemical reaction kinetics. Topics considered include the classical trajectory approach to reactive scattering; periodic orbits and theory of reactive scattering; and semiclassical reactive scattering.

1985-01-01

248

The Chemical Reactions of Sulfur in the Citrate Process for Flue Gas Desulfurization.  

Science.gov (United States)

The Bureau of Mines performed chemical research to elaborate details of sulfur chemistry pertaining to the citrate flue gas desulfurization process in which sulfur dioxide (SO2), absorbed (as bisulfite ion) in a buffered sodium citrate solution, is reduce...

1981-01-01

249

Quarterly progress report for the Chemical and Energy Research Section of the Chemical Technology Division: January--March 1997  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division (CTD) at Oak Ridge National Laboratory (ORNL) during the period January--March 1997. Created in March 1997 when the CTD Chemical Development and Energy Research sections were combined, the Chemical and Energy Research Section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within seven major areas of research: Hot Cell Operations, Process Chemistry and Thermodynamics, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Separations and Materials Synthesis, Solution ...

1998-01-01

250

Pulmonary metabolism of foreign compounds: its role in metabolic activation.  

UK PubMed Central (United Kingdom)

The lung has the potential of metabolizing many foreign chemicals to a vast array of metabolites with different pharmacological and toxicological properties. Because many chemicals require metabolic...Full Text Available

1990-04-01

251

Predicting the carcinogenicity of chemicals in humans from rodent bioassay data.  

UK PubMed Central (United Kingdom)

Regulatory agencies currently rely on rodent carcinogenicity bioassay data to predict whether or not a given chemical poses a carcinogenic threat to humans. We argue that it is always more useful to...Full Text Available

1991-08-01

252

Pore region of TRPV3 ion channel is specifically required for heat-activation  

UK PubMed Central (United Kingdom)

Ion-channels can be activated (gated) by a variety of stimuli including chemicals, voltage, mechanical force or temperature. Whereas molecular mechanisms of ion-channel gating by chemicals and...Full Text Available

2008-09-01

253

Physical Morphology and Quantitative Characterization of Chemical Changes of Weathered PVC/Pine Composites.  

Science.gov (United States)

This study investigated weathering effects on polyvinyl chloride (PVC) based wood plastic composites (WPC), with a focus on the color and structure that is attributed to the material composition. It is directed towards quantifying the main chemical modifi...

2009-01-01

254

Phase transitions in the soliton star model  

Energy Technology Data Exchange (ETDEWEB)

The aim of this paper is to obtain the effective potential of the non-topological soliton model at finite temperature with the assumption that the chemical potential {mu} of the system is different from zero and to analyse how the effective potential is influenced by changes in the chemical potential and temperature. (author)

1998-01-01

255

On the water-chemical regime in steam generators at NPP  

British Library Electronic Table of Contents (United Kingdom)

The effect of the water-chemical regime (WCR) on damage sustained by heating surfaces of steam generators at NPP is analyzed. It is indicated that phosphate treatment with minimal excesses of phosphates in the steamgenerator water is the most optimal method of managing the WCR regime of horizontal steam generators.

2006-01-01

256

On the General Mechanism of Selective Induction of Cytochrome P450 Enzymes by Chemicals: Some Theoretical Considerations  

UK PubMed Central (United Kingdom)

Importance of the fieldThe cytochrome P450 (CYP) isoforms that are selectively induced following exposure to structurally-diverse chemicals often are the ones capable...Full Text Available

2010-04-01

257

Introduction and summary of the 13th meeting of the Scientific Group on Methodologies for the Safety Evaluation of Chemicals (SGOMSEC): alternative testing methodologies.  

UK PubMed Central (United Kingdom)

A workshop on alternative toxicological testing methodologies was convened by the Scientific Group on Methodologies for the Safety Evaluation of Chemicals (SGOMSEC) 26-31 January 1997 in Ispra, Italy,...Full Text Available

1998-04-01

258

Hypothesis for induction and propagation of chemical sensitivity based on biopsy studies.  

UK PubMed Central (United Kingdom)

The reactive airways dysfunction syndrome (RADS), the reactive upper airways dysfunction syndrome (RUDS), the sick building syndrome (SBS), and the multiple chemical sensitivity syndrome (MCS) are overlapping...Full Text Available

1997-03-01

259

Force-dependent chemical kinetics of disulfide bond reduction observed with single-molecule techniques  

UK PubMed Central (United Kingdom)

The mechanism by which mechanical force regulates the kinetics of a chemical reaction is unknown. Here, we use single-molecule force–clamp spectroscopy and protein engineering to study the effect...Full Text Available

2006-05-09

260

Fluorine-19 NMR Chemical Shift Probes Molecular Binding to Lipid Membranes  

UK PubMed Central (United Kingdom)

The binding of amphiphilic molecules to lipid bilayers is followed by 19F NMR using chemical shift and line shape differences between the solution and membrane-tethered states of...Full Text Available

2008-05-22

261

Demonstration and Evaluation of Magnetic Descalers.  

Science.gov (United States)

Mineral scale formation in water distribution piping impedes flow, resulting in pressure and volume reduction and increasing operational costs. Chemical cleaning is both costly and time consuming, and there are health concerns when chemically cleaning pot...

2001-01-01

262

Decontamination of nuclear facilities  

International Nuclear Information System (INIS)

Thirty-seven papers were presented at this conference in five sessions. Topics covered include regulation, control and consequences of decontamination; decontamination of components and facilities; chemical and non-chemical methods of decontamination; and TMI decontamination experience.

1982-09-19

263

Chemical structure and inhalation toxicity of lipopolysaccharides from bacteria on cotton.  

UK PubMed Central (United Kingdom)

Lipopolysaccharides from different bacteria isolated from cotton were purified and chemically analyzed. Their pulmonary toxicity to animals was tested in inhalation tests. Lipopolysaccharides from Agrobacterium...Full Text Available

1980-09-01

264

Chemical effects on K x-ray intensity ratios in chromium compounds  

International Nuclear Information System (INIS)

K_#beta#/ K_#alpha# x-ray intensity ratio of chromium were measured in different chromium compounds. The results show the variation of the intensity ratio as a function of the chemical environment around the metal ion. (author)

2003-02-10

265

Chemical carcinogenesis: too many rodent carcinogens.  

UK PubMed Central (United Kingdom)

The administration of chemicals at the maximum tolerated dose (MTD) in standard animal cancer tests is postulated to increase cell division (mitogenesis), which in turn increases rates of mutagenesis...Full Text Available

1990-10-01

266

Calculations of physical and chemical reactions produced in irradiated water containing DNA  

Energy Technology Data Exchange (ETDEWEB)

Initial results obtained with a Monte Carlo computer program designed to link initial physical events in irradiated liquid water with subsequent chemical and biological events are presented. 10 refs., 4 figs., 3 tabs.

1985-01-01

267

CHEMICAL SPECIATION OF FLUE GAS DESULFURIZATION SLUDGE CONSTITUENTS  

Science.gov (United States)

This project addresses the problem of flue gas desulfurization (FGD) sludge disposal to land. Specifically, the chemical species of FGD sludge constituents are thermodynamically modeled using the equilibrium constant approach, in an attempt to predict the constituent concentratio...

268

Boundary conditions for the paleoenvironment: chemical and physical processes in the pre-solar nebula  

Energy Technology Data Exchange (ETDEWEB)

Two additional hyperfine components of the interstellar radical C3H were detected. In addition, methanol was discovered in interstellar clouds. The abundance of HCCN and various chemical isomers in molecular clouds was investigated.

1985-02-01

269

BIOASSAY AND CHEMICAL ANALYSIS FOR HAZARDOUS MATERIALS IN RESIDUAL OILS. VOLUME 2. APPENDICES  

Science.gov (United States)

The report gives results of an examination, including mutagenic screening, of the chemical composition of residual fuel oils and their column chromatography pre-fractions. A degree of correlation between composition and mutagenicity has been achieved. Radionuclide data has been o...

270

Application of tumor, bacterial and parasite susceptibility assays to study immune alterations induced by environmental chemicals  

UK PubMed Central (United Kingdom)

Model systems to study the effects of chemicals of environmental concern on bacterial and parasitic diseases as well as the immunosurveillance and destruction of transplantable tumor cells were described...Full Text Available

1982-02-01

271

Alteration of the chemical environment disrupts communication in a freshwater fish  

UK PubMed Central (United Kingdom)

It is well established that changes to the chemical environment can impair development, physiology and reproductive biology; by contrast, impacts on communication have not been widely reported. This...Full Text Available

2006-05-22

272

Acidizing subterranean well formations containing deposits of metal compounds  

Science.gov (United States)

Methods of acidizing a subterranean well formation, acidizing compositions, and sequestering additives for preventing the precipitation of metal compounds in the formation are described. Use of the methods and chemicals described should lead to improved formation permeability as compared to use of previous methods and chemicals. 12 claims.

1979-04-24

273

1,3-Butadiene: linking metabolism, dosimetry, and mutation induction.  

UK PubMed Central (United Kingdom)

There is increasing concern for the potential adverse health effects of human exposures to chemical mixtures. To better understand the complex interactions of chemicals within a mixture, it is essential...Full Text Available

1994-11-01

274

Use of organic water treatment chemicals  

International Nuclear Information System (INIS)

For better understanding and proper use of organic chemicals addition data are needed, including kinetic data on the scavenging reactions in actual cycles, data on ambient temperature stability and decomposition, sampling and analsyis information, data on effects in a case of fire, and more corrosion data. Use of these chemicals for layup of boilers and other equipment needs to be evaluated for each application. After a preliminary evaluation, such as outlined in this report, every new water treatment chemical should be evaluated in at least two month test in actual steam cycle. (orig.).

275

The preparation of carrier-free "2"0"3Pb for medical use  

International Nuclear Information System (INIS)

... bismuth 203 chemical reactions cyclotrons decay helium 3 beams impurities

277

The Modification of Polymer Surfaces and the Fabrication of ...  

Science.gov (United States)

... spatially defined fashion. Many surface modification techniques require a sequential chemical treatment of the surface.6 ...

1993-06-10

280
281

Plasma Enhanced Chemical Vapor Deposition (PECVD) Application And Atmospheric Pressure Plasma Characteristics  

International Nuclear Information System (INIS)

Atmospheric pressure plasma enhanced chemical vapour deposition system is built. The electrical and optical characteristics of the APPECVD system is given. The system is used to deposit conductive polymers and nano composites onto glass and metal surfaces. The morphological, optical, chemical and electrical characteristics of deposited surfaces are investigated using SEM, AFM four probe deposition purposes. The photovoltaic applications of plasma deposited polymers and nonconsumption are compared with deposited with electrochemical methods show different results. The electrical, chemical and morphological structures of the samples will be given.

2008-08-25

283

Nanostructured Materials from Impulse Plasma in Liquid  

International Science & Technology Center (ISTC)

Nanostructured Materials from Impulse Plasma in Liquid: Studying of Physical-Chemical Properties, Optimization of Conditions of Obtaining

284

Molecular models in the quantum-chemical investigation of the structure of defect centers on oxide catalysts  

Energy Technology Data Exchange (ETDEWEB)

Several possibilities of the use of molecular models in quantum-chemical investigations of the structure of defect centers on the surfaces of oxides on nontransition elements have been illustrated. There has been a special discussion of the assumption of the local nature of the chemical interactions in these systems, which underlies such an approach, and of the consequent laws governing the formation of their lattices in the example cases of zeolites, kaolinites, and comparable boron- and aluminum-containing oxides. A quantum-chemical interpretation of the body of experimental data from investigations of the dehydroxylation of H forms of zeolites has been given. The structure of the Lewis acid centers formed as a result, and their chemisorption properties, have been discussed.

1987-05-01

285

Magnetic properties of oxovanadium(IV) complexes with bidentate on donor Schiff bases  

International Nuclear Information System (INIS)

(Feb 1977). Japan Syamal, A. Bombay Univ. (India). Univ. Dept. of Chemical

1977-01-01

286

MINEQL-PC. Chemical Equilibrium Composition of Aqueous Systems  

Energy Technology Data Exchange (ETDEWEB)

MINEQL is a subroutine package to calculate equilibrium composition of an aqueous system, accounting for mass transfer.

1986-11-21

287

Low-Cost Crystal Silicon  

International Science & Technology Center (ISTC)

The Development of Basic Plasma-Chemical Technology for Manufacture of Low Cost Crystal Silicon for Solar Power Plants.

289

Emergency Planning and Community Right-to-Know Act: Section 313 release reporting requirements (August 1991)  

International Nuclear Information System (INIS)

The brochure contains information about the Emergency Planning and Community Right-to-Know Act. This law establishes a structure at the state and local levels to assist communities in planning for chemical emergencies and requires facilities to provide information on various chemicals present in the community. The Act requires that this information be made available to the public. One of the requirements concerns the reporting of annual releases of toxic chemicals to the air, water, and land. These provisions are outlined in Section 313 which mandates annual release reporting for over 300 chemicals.

290

Effects of variable hardness, ph, alkalinity, suspended clay, and humics on the chemical speciation and aquatic toxicity of copper  

Science.gov (United States)

The effects of variable hardness, pH, alkalinity, humics, and suspended clay on the chemical speciation of copper and its toxicity to fathead minnow larvae in Lake Superior water were investigated. Two proposed methods (toxicity factors and chemical speciation) for predicting LC50 values in specific natural waters from laboratory toxicity data and the average site specific values of general water quality parameters were evaluated. The accuracy of the cupric ion-selective electrode in determining CU/sup +2/ activities in ambient and chemically altered Lake Superior water was also determined.

1986-03-01

292

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds  

Energy Technology Data Exchange (ETDEWEB)

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds were studied by electron and proton bombardments. L{sub {gamma}1} X-rays which involve transition of 4d electrons of the valence shell were found to be sensitive to the chemical environment. The L{sub {gamma}1}/L{sub {beta}1} X-ray intensity ratio increased with an increase of the 4d electron occupation of niobium or molybdenum in niobium or molybdenum compounds, showing that the chemical effects can be ascribed to the 4d electron behavior of the metallic atom in its compounds. (orig.).

1990-12-20

293

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds  

International Nuclear Information System (INIS)

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds were studied by electron and proton bombardments. L_#gamma#_1 X-rays which involve transition of 4d electrons of the valence shell were found to be sensitive to the chemical environment. The L_#gamma#_1/L_#beta#_1 X-ray intensity ratio increased with an increase of the 4d electron occupation of niobium or molybdenum in niobium or molybdenum compounds, showing that the chemical effects can be ascribed to the 4d electron behavior of the metallic atom in its compounds. (orig.).

1990-12-01

294

Biomass as feedstock for chemicals and energy on the threshold of the 21st. century  

International Nuclear Information System (INIS)

A historical background is first given in which the role of biomass is described in relation to its competition with fossil biomass for the production of chemicals and energy. Occurrences of reserves from both sources are then compared. Petrochemical and biomass routes are then analyzed in terms of their relative competitive advantages. The oleochemical and biotechnology cases are analyzed in more detail as examples of biomass utilization. Latin American examples of industrial manufacturing of biomass derived chemicals are then provided. Alcochemicals are analyzed in detail as well as essential oils and other chemicals. Finally, references are made to regional Latin American initiatives regarding biomass and the objectives, organization and nature of the initiative are presented.

295

Absorption-Electrochemical Surface Decontamination  

International Science & Technology Center (ISTC)

Development of a Comprehensive Decontamination Database and an Absorption-Electrochemical Metal Surface Decontamination Technique Combining Chemical and Electrochemical Process

296

A comparative study of the fatty acid composition of prochloron lipids  

Science.gov (United States)

The chemical analysis of lipids of Prochloron isolated from several hosts is discussed. The object

1983-01-01

297

Thermodynamics of reactions of chemically stable ceramics formation  

Energy Technology Data Exchange (ETDEWEB)

Theoretical thermodynamical calculations for the ZrO/sub 2/- Al/sub 2/O/sub 3/-SiO/sub 2/ system are given to expose the regions of the most chemically stable products of crystallization. It is established that ceramics on the base of mullite with zircon addition and containing the minimum quantity of glass phase should be preferably used in chemical media containing HCl.

1981-06-01

298

Theory of chemical reaction dynamics. Volume 1  

Energy Technology Data Exchange (ETDEWEB)

This book examines some of the basic principles behind chemical reactions kinetics. Topics considered include ab initio determination of potential energy for chemical reactions; semi-empirical potential energy surfaces; general theory of reactive scattering: different equation approach; and integral equation approach to reactive scattering.

1985-01-01

299

Sustainable phosphorous fertilisation of potatoes (Potato CHIPS)  

Environmental Research Database

DescriptionThis project has two independent aims: (1) to investigate the use of struvite as an alternative to chemical P fertilisers and (2) to develop an oligonucleotide microarray to monitor the P status of the potato crop. The UK horticultural and agricultural industries rely on large inputs of phosphate (P) fertilisers to maintain crop yields and quality. However, the use of non-renewable, chemical P fertilisers is unsustainable, and the alternatives to chemical P-fertilisers must be identified as an [continued...

2008-01-31

300

Request for interim approval to operate Trench 94 of the 218-E-12B Burial Ground as a chemical waste landfill for disposal of polychlorinated biphenyl waste in submarine reactor compartments. Revision 2.  

Science.gov (United States)

This request is submitted to seek interim approval to operate a Toxic Substances Control Act (TSCA) of 1976 chemical waste landfill for the disposal of polychlorinated biphenyl (PCB) waste. Operation of a chemical waste landfill for disposal of PCB waste ...

1994-01-01

301

Microwaves action applied to chemical reactions and processes; L`azione delle microonde nelle reazioni e nei processi chimici  

Energy Technology Data Exchange (ETDEWEB)

Microwaves improve the rate of many chemical reactions either interacting with the solvent, when the reaction is carried out in solution, or with the surface of a solid substrate where a suitable reagent is dispersed (dry chemistry). A few examples of chemical reactions positively affected by microwaves are described: particularly interesting are those concerning polymers and radio-pharmaceuticals.

1997-03-01

302

Investigation of morphology and chemical composition of self-organized semiconductor quantum dots and wires by X-ray scattering  

International Nuclear Information System (INIS)

X-ray scattering methods suitable for the investigation of the morphology and chemical composition of self-organized quantum dots and quantum wires are reviewed. Their application is demonstrated in experimental examples showing that a combination of small angle X-ray scattering with high-resolution X-ray diffraction can reveal both the shape and the chemical composition of the self-organized objects. (author)

2001-09-23

303

Evaluation of indoor and outdoor climate on sites polluted with volatile organic chemicals  

International Nuclear Information System (INIS)

Papers presented at a meeting on indoor and outdoor climates on sites polluted with volatile organic chemicals. The papers deal with the subject of evaporation of organic chemicals on the polluted sites in relation to the influence on indoor and outdoor climates. Themes dealt with are diffusion through soils and transport of pollutants from the soil into buildings. (AB).

1993-11-04

304

Environmentally-Induced Malignancies: An In Vivo Model to Evaluate the Health Impact of Chemicals in Mixed Waste  

Energy Technology Data Exchange (ETDEWEB)

Occupational and environmental exposure to organic ligands, solvents, fuel hydrocarbons, and polychlorinated biphenyls are linked with increased risk of hematologic malignancies. DOE facilities and waste sites in the U.S. are contaminated with mixtures of potentially hazardous chemicals such as metals, organic ligands, solvents, fuel hydrocarbons, polychlorinated biphenyls and radioactive isotopes. A major goal of this project was to establish linkage between chemical/radiation exposure and induction of genomic damage in target populations with the capability to undergo transformation.

2001-05-04

305

Detection device for high explosives  

Energy Technology Data Exchange (ETDEWEB)

A portable fiber optic detector that senses the presence of specific target chemicals by electrostatically attracting the target chemical to an aromatic compound coating on an optical fiber. Attaching the target chemical to the coated fiber reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.

1992-01-01

306

Chemicals from coal: New processes  

Energy Technology Data Exchange (ETDEWEB)

This book deals specifically with the development of new processes of converting coal into useful chemical feedstocks. The major topic in this volume is the generation of syngas and its catalytic conversion to chemicals via the Fischer-Tropsch synthesis. Describes processes involved in conversion, recent catalytic developments, and the commercially important Sasol process. Also includes chapters on the carbide process and potential of future developments in the field.

1987-01-01

307

Chemical sensitivity of the Ksub(. beta. )/Ksub(. cap alpha. ) x-ray intensity ratio for 3d elements  

Energy Technology Data Exchange (ETDEWEB)

Chemical influences on the relative Ksub(..beta..)/Ksub(..cap alpha..) x-ray intensity ratio up to five per cent were found for different chemical constitutions of Cr, Mn, Fe and Cu by very precise PIXE measurements. In the discussion of these effects, screening of 3p electrons by a varying 3d valence charge, as well as polarizational effects are of importance.

1982-12-28

308

Chemical sensitivity of the Ksub(#nu#)/Ksub(#alpha#) x-ray intensity ratio for 3d elements  

International Nuclear Information System (INIS)

Chemical influences on the relative Ksub(#nu#)/Ksub(#alpha#) x-ray intensity ratio up to five per cent were found for different chemical constitutions of Cr, Mn, Fe and Cu by very precise PIXE measurements. In the discussion of these effects, screening of 3p electrons by a varying 3d valence charge, as well as polarisational effects are of importance. (author).

1982-12-01

309

Chemical assessments for international programmes III  

Environmental Research Database

DescriptionThis project continues DEFRA's commitment to the International Programme on Chemical Safety, a joint WHO/ILO/UNEP programme. DEFRA's contribution involves preparing Environmental Health Criteira Documents (EHCs), Concise International Chemical Assessments Documents (CICADS) and input to the OECD test Guidelines Programme and gneral risk assessment guidance. Peer reviews of documents prepared through other research in the IPCS network have also been carried out,as well as attending and hosting ta [continued...

2005-01-21

310

Catalytic chemistry  

Energy Technology Data Exchange (ETDEWEB)

Most chemical reactions in industry and biology are catalytic and play a role at some stage of the processing of about 80% of the goods manufactured in the U.S., yet catalysis is a neglected subject in chemical education. This book integrates the fragmentary treatment accorded the topic until now. It covers, in a unified way, catalysis in solutions, by enzymes, in synthetic polymers within the molecular scale cages of zeolites and other molecular sieves, and on surfaces of inorganic solids. The central ideas are chemical; and principles are illustrated by emphasizing industrial reactions and catalysts.

1991-01-01

311

Tris(2,2'-bipyridyl)ruthenium(II) electrogenerated chemiluminescence sensor based on carbon nantube dispersed in sol-gel-derived titania-Nafion composite films  

International Nuclear Information System (INIS)

A highly sensitive and stable tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)_3 "2"+) electrogenerated chemiluminescence (ECL) sensor was developed based on carbon nanotube (CNT) dispersed in mesoporous composite films of sol-gel titania and perfluorosulfonated ionomer (Nafion). Single-wall (SWCNT) and multi-wall carbon nanotubes (MWCNT) can be easily dispersed in the titania-Nafion composite solution. The hydrophobic CNT in the titania-Nafion composite films coated on a glassy carbon electrode certainly increased the amount of Ru(bpy)_3 "2"+ immobilized in the ECL sensor by adsorption of Ru(bpy)_3 "2"+ onto CNT surface, the electrocatalytic activity towards the oxidation of hydrophobic analytes, and the electronic conductivity of the composite films. Therefore, the present ECL sensor based on the CNT-titania-Nafion showed improved ECL sensitivity for tripropylamine (TPA) compared to the ECL sensors based on both titania-Nafion composite films without CNT and pure ...

2006-04-13

312

Tris(2,2'-bipyridyl)ruthenium(II) electrogenerated chemiluminescence sensor based on carbon nantube dispersed in sol-gel-derived titania-Nafion composite films  

Energy Technology Data Exchange (ETDEWEB)

A highly sensitive and stable tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy){sub 3} {sup 2+}) electrogenerated chemiluminescence (ECL) sensor was developed based on carbon nanotube (CNT) dispersed in mesoporous composite films of sol-gel titania and perfluorosulfonated ionomer (Nafion). Single-wall (SWCNT) and multi-wall carbon nanotubes (MWCNT) can be easily dispersed in the titania-Nafion composite solution. The hydrophobic CNT in the titania-Nafion composite films coated on a glassy carbon electrode certainly increased the amount of Ru(bpy){sub 3} {sup 2+} immobilized in the ECL sensor by adsorption of Ru(bpy){sub 3} {sup 2+} onto CNT surface, the electrocatalytic activity towards the oxidation of hydrophobic analytes, and the electronic conductivity of the composite films. Therefore, the present ECL sensor based on the CNT-titania-Nafion showed improved ECL sensitivity for tripropylamine (TPA) compared to the ECL sensors based on both titania-Nafion ...

2006-04-13

313

Surfactant based sol-gel approach to nanostructured LiFePO{sub 4} for high rate Li-ion batteries  

Energy Technology Data Exchange (ETDEWEB)

Porous nanostructured LiFePO{sub 4} powder with a narrow particle size distribution (100-300nm) for high rate lithium-ion battery cathode application was obtained using an ethanol based sol-gel route employing lauric acid as a surfactant. The synthesized LiFePO{sub 4} powders comprised of agglomerates of crystallites <65nm in diameter exhibiting a specific surface area ranging from 8m{sup 2}g{sup -1} to 36m{sup 2}g{sup -1} depending on the absence or presence of the surfactant. The LiFePO{sub 4} obtained using lauric acid resulted in a specific capacity of 123mAhg{sup -1} and 157mAhg{sup -1} at discharge rates of 10C and 1C with less than 0.08% fade per cycle, respectively. Structural and microstructural characterization were performed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) with energy dispersive X-ray (EDX) analysis while electronic conductivity and specific surface area ...

2007-01-01

314

Source tracking of Escherichia coli by 16S-23S intergenic spacer region denaturing gradient gel electrophoresis (DGGE) of the rrnB ribosomal operon.  

Science.gov (United States)

This research validates a novel approach for source tracking based on denaturing gradient gel electrophoresis (DGGE) analysis of DNA extracted from Escherichia coli isolates. Escherichia coli from different animal sources and from river samples upstream from, at, and downstream of a combined sewer overflow were subjected to DGGE to determine sequence variations within the 16S-23S intergenic spacer region (ISR) of the rrnB ribosomal operon. The ISR was analyzed to determine if E. coli isolates from various animal sources could be differentiated from each other. DNA isolated from the E. coli animal sources was PCR amplified to isolate the rrnB operon. To prevent amplification of all 7 E. coli ribosomal operons by PCR amplification using universal primers, sequence-specific primers were utilized for the rrnB operon. Another primer set was then used to prepare samples of the 16S-23S ISR for DGGE. Comparison of PCR-DGGE results between human and animal sources revealed ...

2007-10-01

315

Simultaneous lowering of serum phosphate and LDL-cholesterol by sevelamer hydrochloride (RenaGel) in dialysis patients.  

Science.gov (United States)

The aim of the current investigation was to study the effects of sevelamer hydrochloride (RenaGel) on serum phosphate, intact parathyroid hormone levels (iPTH), and lipid profiles in stable hemodialysis patients. Hemodialysis patients maintained on calcium containing phosphate binders were enrolled in this study. Following two weeks of washout of the phosphate binders, serum phosphate rose from 6.4 +/- 0.6 to 10.5 +/- 0.7 mg/dl (p <0.001). After 8 weeks of titration with sevelamer hydrochloride, serum phosphate fell by 4.5 +/- 0.3 to 6.3 +/- 0.7 mg/dl (p <0.0001). Serum calcium levels fell during washout (9.8 +/- 0.4 to 8.9 +/- 0.3 mg/dl, p <0.004) and were unaffected by sevelamer hydrochloride. Sevelamer hydrochloride administration was associated with a 23.0 +/- 3.1% fall in total cholesterol, a 35.9 +/- 3.0% fall in LDL cholesterol, and a 35.2 +/- 5.3% fall in the LDL:HDL cholesterol ratio (p <0.001). There was no change in HDL cholesterol, ...

1998-12-01

316

Gel-based proteomics of liver cancer progression in rat.  

Science.gov (United States)

A significant challenge in proteomics biomarker research is to identify the changes that are of highest diagnostic interest, among the many unspecific aberrations associated with disease burden and inflammation. In the present study liver tissue specimens (n=18) from six experimental stages were collected from the resistant hepatocyte (RH) rat model of liver cancer and analyzed by 2D DIGE. The study included triplicates of regenerating liver, control "sham-operated" liver, three distinct premalignant stages and hepatomas. Out of 81 identified proteins two-thirds were differentially abundant in rat hepatomas compared to control rat liver and, secondly, the majority of proteins were also changed in precursor stages. This underscores the importance of adequate control samples in explorative cancer biomarker research. We confirm several proteomic changes previously identified in human hepatocellular carcinoma (HCC) and we identify novel candidate proteomic aberrations for further analysis ...

2011-06-06

317

Formation and capacitance of Nb{sub 2}O{sub 5} thin film on aluminum foil by sol-gel process; Zoru-geru ho niyoru aruminiumuhakujo eno Nb{sub 2}O{sub 5} hakumaku no sakusei to yoryotokusei  

Energy Technology Data Exchange (ETDEWEB)

Nb{sub 2}O{sub 5} thin films were formed on aluminum foils by a sol-gel process in order to increase the capacitance of the aluminum foils which are used as aluminum electrolytic capacitors. Investigations focussed on the preparation and characterization of the coating solution, the formation of Nb{sub 2}O{sub 5} thin films on aluminum foils, and the heat treatment and anodization of the films. The phase transition and electrical properties, such as capacitance, leakage current, and withstand voltage of the Nb{sub 2}O{sub 5} thin films were also measured. The Nb{sub 2}O{sub 5} thin films annealed at temperatures below 550 degree C were found to be amorphous, but they were crystallized to the orthorhombic phase by annealing at temperatures higher than 580 degree C. The capacitance of the coated samples increased with an increase in the thickness of the formed Nb{sub 2}O{sub 5} thin films, but an increase in leakage current and a decrease in withstand voltage were ...

1999-12-01

318

Enhanced biosorption of nickel(II) ions by silica-gel-immobilized waste biomass: Biosorption characteristics in batch and dynamic flow mode  

Energy Technology Data Exchange (ETDEWEB)

Batch and dynamic flow biosorption studies were carried out using the waste biomass entrapped in silica-gel matrix for the removal of nickel(II) ions from synthetic solutions and real wastewater. Batch biosorption conditions were examined with respect to initial pH, S/L ratio, contact time, and initial nickel ion concentration. Zeta potential measurements showed that immobilized biosorbent was negatively charged in the pH range of 3.0-8.0. The immobilized biomass was found to possess relatively high biosorption capacity (98.01 mg g{sup -1}), and biosorption equilibrium was established in a short time of operation (5 min). The equilibrium data were followed by Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models. Scanning electron microscope analysis was used to screen the changes on the surface structure of the waste biomass after immobilization and nickel(II) biosorption. Sorbent-sorbate interactions were confirmed by Fourier transform infrared ...

2009-04-30

319

Characterization of the major phosphoprotein and its kinase on the surface of the rat adipocyte  

Energy Technology Data Exchange (ETDEWEB)

Intact rat fat cell exposed to 12.5 ..mu..M (..gamma..-32P)ATP incorporate label into specific proteins within minutes. By solubilizing the reaction mixture with SDS which bypasses the subcellular fractionation steps, the labeled proteins can be identified in autoradiographs of SDS-PAGE gels. The most prominently labeled protein has an M/sub r/ of 42,000. Localization of this component to the cell surface can be made on the basis of inhibition of phosphorylation by addition of a protein derived from the rat brain with protein kinase inhibitory property, susceptibility of the phosphorylated protein to the tryptic digestion, inhibition of phosphorylation of this protein after brief exposure to melittin. To rule out the possibility that the cell surface protein might be a mitochondrial contaminant from broken cells, /sup 32/Pi-labeled and (..gamma..-/sup 32/P)ATP-labeled cells were chromatographed on a rabbit anti-pyruvate dehydrogenase antibody-Sepharose 4B column. A ...

1986-12-01

320

A novel chenodeoxycholic derivative HS-1200 induces apoptosis in human HT-29 colon cancer cells  

International Nuclear Information System (INIS)

To investigate the growth inhibitory effects, and the underlying mechanism of human colon cancer cell (HT-29) death, induced by a new synthetic bile derivative (HS-1200). Human colon cancer cells (HT-29), in exponential growth phase, were treated with various concentrations of a new synthetic bile acid derivative (HS-1200). The growth inhibitory effects on HT-19 cells were examined using a trypan blue exclusion assay. The extent of apoptosis was determined using agarose gel electrophoresis, TUNEL assays and Hoechst staining. The apoptotic cell death was also confirmed by Western blotting of PARP, caspase-3 and DNA fragmentation factor (DFF) analysis. To investigate the involvement of mitochondria, we employed immunofluorescent staining of cytochrome c and mitochondrial membrane potential analyses. The dose required for the half maximal inhibition (IC_5_0) of the HT-29 cell growth was 100 #approx# 150 #mu# M of HS-1200. Several changes, associated with the apoptosis ...

2002-12-01

321

Radiosensitization of human lung fibroblasts by chemicals that decrease ATP levels  

International Nuclear Information System (INIS)

Radiosensitization by lactate, pyruvate, nalidixic acid and novobiocin was studied in exponentially growing SH-18L human lung fibroblasts. All the chemicals had a slight radiosensitizing effect at a low concentration and a definite effect at a higher one. Decreases in the D_0 and/or Dq values were present in each dose survival curve. Fibroblasts incubated with the low concentration of each chemical for 24 hrs after X irradiation showed no reduction in intracellular ATP content, whereas, the higher concentration produced a significant decrease. These observations suggest that the decrease in the ATP content may be involved in the radiosensitization of human fibroblasts at high concentrations of these chemicals. In contrast, radiosensitization at a low concentration is not explained by a relationship to ATP content. Different mechanisms may be involved in radiosensitization at low and high concentrations of these ...

322

Natural plant chemicals: source of industrial and medicinal materials  

Energy Technology Data Exchange (ETDEWEB)

Many higher plants produce economically important organic compounds such as oils, resins, tannins, natural rubber, gums, waxes, dyes, flavors and fragrances, pharmaceuticals, and pesticides. However, most species of higher plants have never been described, much less surveyed for chemical or biologically active constituents, and new sources of commercially valuable materials remain to be discovered. Advances in biotechnology, particularly methods for culturing plants cells and tissues, should provide new means for the commercial processing of even rare plants and the chemicals they produce. These new technologies will extend and enhance the usefulness of plants as renewable resources of valuable chemicals. In the future, biologically active plant-derived chemicals can be expected to play an increasingly significant role in the commercial development of new products for regulating plant growth and for ...

1985-01-01

323

Evaluation of the long-term mechanical behavior in the near-fields considering chemical transitions of barrier materials  

International Nuclear Information System (INIS)

An analysis system for the long-term mechanical behavior of barrier materials (MACBECE: Mechanical Analysis system considering Chemical transitions of BEntonite-based and CEment-based materials) was developed in order to improve the reliability of the evaluation of the hydraulic field which is one of the important environmental conditions in the safety assessment of the TRU waste disposal. MACBECE is the system that calculates the deformation of barrier materials using their chemical property changes as inputs, and subsequently calculates their hydraulic conductivity taking both their chemical property changes and deformation into consideration. By using MACBECE, the long-term deformation and the transition of hydraulic field for the round-type disposal cavities were evaluated, assuming some sets of chemical evolution data as input. Based on the analysis result, it is considered that the influence of ...

2007-04-22

324

Structure activity relationships to assess new chemicals under TSCA  

International Nuclear Information System (INIS)

Under Section 5 of the Toxic Substances Control Act (TSCA), manufacturers must notify the US Environmental Protection Agency (EPA) 90 days before manufacturing, processing, or importing a new chemical substance. This is referred to as a premanufacture notice (PMN). The PMN must contain certain information including chemical identity, production volume, proposed uses, estimates of exposure and release, and any health or environmental test data that are available to the submitter. Because there is no explicit statutory authority that requires testing of new chemicals prior to their entry into the market, most PMNs are submitted with little or no data. As a result, EPA has developed special techniques for hazard assessment of PMN chemicals. These include (1) evaluation of available data on the chemical itself, (2) evaluation of data on analogues of the PMN, or evaluation of data on ...

1990-06-27

325

Density functional calculations of 15N chemical shifts in solvated dipeptides  

International Nuclear Information System (INIS)

We performed density functional calculations to examine the effects of solvation, hydrogen bonding, backbone conformation, and the side chain on 15N chemical shielding in proteins. We used N-methylacetamide (NMA) and N-formyl-alanyl-X (with X being one of the 19 naturally occurring amino acids excluding proline) as model systems. In addition, calculations were performed for selected fragments from protein GB3. The conducting polarizable continuum model was employed to include the effect of solvent in the density functional calculations. Our calculations for NMA show that the augmentation of the polarizable continuum model with the explicit water molecules in the first solvation shell has a significant influence on isotropic 15N chemical shift but not as much on the chemical shift anisotropy. The difference in the isotropic chemical shift between the standard ?-sheet and ?-helical conformations ranges ...

2008-06-01

326

Chemical source identifications for natural resource injury/damage assessments and site assessments  

International Nuclear Information System (INIS)

Current regulations guiding technical aspects of natural resource damage assessments combine source, exposure pathway, resource injury, and monetary damage components. In order to associate any observed injury to the uncontrolled release of chemicals (e.g. oil spills, contaminated sediments, in-place toxics, etc.), it is important to link the chemical ''release'' to the injured resource. In complex environmental settings where multiple sources of similar chemicals are combined, multicomponent chemical methods must be used to link the release to the environmental distribution of chemicals. Three examples of the utility of multicomponent organic chemical analyses linked to comprehensive and representative sampling strategies will be discussed--the Shell Martinez Refinery oil spill, the Exxon Valdez oil spill, and a contaminated sediment assessment. These ...

1993-11-14

327

MENTOR-BASED EFFORT TO ADVANCE IMPLEMENTATION OF PREFERRED MANAGEMENT PRACTICES (PMPS) FOR OIL PRODUCERS IN SOUTH MIDCONTINENT (OKLAHOMA/ARKANSAS) AND WEST COAST (CALIFORNIA) REGIONS  

Energy Technology Data Exchange (ETDEWEB)

The Petroleum Technology Transfer Council (PTTC) and cooperating Regional Lead Organizations (RLOs) in its South Midcontinent (Oklahoma Geological Survey, Norman, Oklahoma) and West Coast (University of Southern California, Los Angeles, California) regions conducted a ''Mentor-Based Effort to Advance Implementation of Preferred Management Practices (PMPs) For Oil Producers'' (DE-FC26-01BC15272) under an award in Phase I of Department of Energy's (DOE's) PUMP (Preferred Upstream Management Practices) program. The project's objective was to enable producers in California, Oklahoma and Arkansas to increase oil production, moderating or potentially reversing production declines and extending the life of marginal wells in the near term. PTTC identified the primary constraints inhibiting oil production through surveys and PUMPer direct contacts in both regions. The leading common constraint was excess produced water and ...

2004-12-01

328

Simultaneous quantitative measurement of biodegradability and toxicity of environmental chemicals  

International Nuclear Information System (INIS)

Investigations were made on the biodegradability and bacterial toxicity of chemicals. The intention was to obtain data necessary for estimating and judging the behaviour of these chemicals during aerobic biological waste water treatment. The course of biodegradation and toxicity with time and concentration could be measured, quantified and described. As test procedure, the respirometric dilution method was used. This method is based on a die away test with continuous measuring of the oxygen used for biochemical oxidation processes. The course of the oxygen demand with time and concentration shows the biodegradation and toxicity patterns of the tested chemical. A variety of household and industrial chemicals were investigated. One group of substances were microbiocides, some of which showed toxic effects at concentrations less than 20 mg/l while others were biodegradable even at concentrations of 200 ...

1994-04-01

329

Conversion of a plasma enhanced chemical vapor deposited silicon-carbon-nitride thin film at ultra-low temperature by oxygen plasma  

Energy Technology Data Exchange (ETDEWEB)

In this work we present an ultra-low temperature method for the oxidation of an amorphous silicon-carbide-nitride (SiCN) material. The SiCN is deposited on silicon substrates by plasma enhanced chemical vapor deposition using CH{sub 4}, SiH{sub 4}, and N{sub 2} chemistry. The physical and chemical properties are characterized for the as-deposited SiCN and post-oxidized films are discussed. The SiCN film is exposed to oxygen plasma, where it undergoes a chemical transformation into a binary SiO{sub 2} material system. A 1.7 nm/min oxidation rate is typical for this process and compares favorably to oxidation methods utilizing much higher temperatures. The substrate temperature remains extremely low throughout the oxidation process, T{sub s} < 200 deg. C. Changes in film stress, optical constants, film thickness, surface roughness, and film density are measured. Chemical analysis by X-ray ...

2008-01-30

330

Radiation preservation of foods of plant origin. Part IV. Subtropical fruits: citrus, grapes, and avocados  

Energy Technology Data Exchange (ETDEWEB)

Current information on the use of ionizing radiation for improving the storage of subtropical fruits like citrus, grapes, and avocados is reviewed. The feasibility of applying radiation either alone or in combination with other physical or chemical treatments for the control of postharvest fungal diseases is considered. Irradiation effects on the physiology of the fruits as related to respiration, ethylene evolution, changes in major chemical constituents, and quality are discussed. The recent trends in the possible use of irradiation as an alternative treatment to chemical fumigants for disinfestation of citrus and avocados and the prospects for the future application of irradiation for preservation of some of these fruits are outlined. 128 references.

1986-01-01

331

Proceedings of the 8. CANMET/ACI international conference on superplasticizers and other chemical admixtures in concrete : supplementary papers[ACI SP-239  

Energy Technology Data Exchange (ETDEWEB)

This book provided a set of supplementary papers provided to delegates at the eighth international CANMET/ACI conference on superplasticizers and chemical admixtures in concrete. Recent research on chemical admixtures and superplasticizers was presented along with new approaches to the practical application of concrete admixtures. The presentations highlighted technological advances in the development of superplasticizers and new approaches to the manufacture and implementation of aggregates. Issues regarding the application of plasticizers with various aggregates were addressed, and interactions between cements and superplasticizers were evaluated. Four of the supplementary papers have been catalogued separately for inclusion in this database. refs., tabs., figs.

2006-07-01

332

Influence of anaerobic microbial activity on biosorption of 2,4-dichlorophenol  

Energy Technology Data Exchange (ETDEWEB)

Biosorption is an important removal mechanism in treating hydrophobic toxic organics in biological reactors. Equilibrium sorption isotherms and sorption kinetics of 2,4-dichlorophenol on live and chemically inactive anaerobic granules were studied. A metabolic inhibitor was used to inactivate the biological activity of the biomass. Results showed that the difference in the biosorption of live and chemically inactive anaerobic granules is not significant. This would suggest that anaerobic biosorption is mainly a physical-chemical process and that metabolic-mediated diffusion in the process is negligible. 12 refs., 3 tabs., 7 figs.

1995-12-31

333

Development of a chemically assisted micro-beam etching system for three-dimensional microanalysis  

Energy Technology Data Exchange (ETDEWEB)

A chemically assisted micro-beam etching system for 3D microanalysis was designed. Using chemically assisted ion beam etching (CAIBE) method with FIB shave-off scanning, about several hundred micrometers clean cross-section will be acquired in a few hours. We use focused ion beam (FIB) and electron beam (EB) as micro-beams, halogen or halide mainly as reactive gases. The apparatus was manufactured based on this concept. We found that the FIB, Q-MS and SED worked as expected. The instrumentation has been completed.

2003-01-15

334

Chemical compatibility study of Cooley L18KU, Herculite, and Elephant Mat with Hanford tank waste  

Energy Technology Data Exchange (ETDEWEB)

An independent chemical compatibility review of various wrapping and absorbent/padding materials was conducted to evaluate resistance to chemicals and constituents present in liquid waste from the Hanford underground tanks. These materials will be used to wrap long-length contaminated equipment when such equipment is removed from the tanks and prepared for transportation and subsequent disposal or storage. The materials studied were Cooley L18KU, Herculite, and Elephant Mat. The study concludes that these materials are appropriate for use in this application.

1998-06-23

335

Why the United States Must Deploy a National Missile ...  

Science.gov (United States)

... transItion to more capable space-based interceptors as ... ten wtth bmlogtcal, and thirty with chemical weapons. ... are becoming the weapon of choice ...

2011-05-14

336

WKK-potential in the chemical industry; WKK-potentieel in de chemische industrie  

Energy Technology Data Exchange (ETDEWEB)

The Netherlands Chemical Industry Association (VNCI) is investigating the potential for expansion of the CHP capacity in the Dutch chemical industry. This report discusses the return on investment for CHP installations and the market conditions. Moreover, scenario results are presented for the CHP potential and the development of CHP in the chemical industry until 2020. [Dutch] De Vereniging van de Nederlandse Chemische Industrie (VNCI) heeft onderzoek laten uitvoeren om vast te stellen welke economische en beleidsmatige voorwaarden er zijn om het WKK-potentieel in de Nederlandse chemie te realiseren. Dit rapport brengt de marktpositie van WKK en de rentabiliteit van investeringen in WKK in beeld. Verder worden resultaten gegeven voor de potentiele energiebesparing en emissiereductie en wordt een scenario gepresenteerd voor het WKK-potentieel in de chemische industrie tot 2020.

2009-11-15

337

Today in History: December 17  

Science.gov (United States)

as manufacturing plants and laboratories, including the Chemical Laboratory at the House of David in Benton Harbor, Michigan. Built in America: Historic Building Buildings Survey/...

2010-12-17

338

Thermodynamic, Transport and Chemical Properties of " ...  

Science.gov (United States)

... Chem. Res., in press, 2006. 8. Smith, BL, Bruno, TJ, Advanced distillation curve measurement with a model predictive temperature controller. Int. ...

2006-06-01

339

Theory of the crystal-liquid phase transition  

Science.gov (United States)

The SCF approximation is used in a statistical theory of melting based on equality of the chemical potentials. The results for the melting points of the inert gases are close to the observed values.

1967-02-01

340

Theoretical Basis of Protocols for Seed Storage  

UK PubMed Central (United Kingdom)

The protocols presently established for optimum seed storage do not account for the chemical composition of different seed species, the physiological status of the seed, and the physical status of water...Full Text Available

1990-11-01

342

The Structure of Plant Cell Walls  

UK PubMed Central (United Kingdom)

The molecular structure, chemical properties, and biological function of the xyloglucan polysaccharide isolated from cell walls of suspension-cultured sycamore (Acer pseudoplatanus)...Full Text Available

1973-01-01

343

Synthesis, Characterization and Chondroprotective Properties of a Hyaluronan Thioethyl Ether Derivative  

UK PubMed Central (United Kingdom)

Hyaluronan (HA), a non-sulfated glycosaminoglycan, is widely used in the clinic for viscosurgery, viscosupplementation, and treatment of osteoarthritis. Four decades of chemical modification...Full Text Available

2008-04-01

347

Research Activities in the Spokane, Washington, Field Office...  

Science.gov (United States)

other chemical applications include use in water softeners, detergents, and food additives. The development of phosphate resources as a leasable commodity provides income to...

2011-08-20

348

Report on NCI symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. II. Cellular and animal models  

International Nuclear Information System (INIS)

The point at which the common final pathway for induction of cancer by chemical carcinogens and ionizing radiation has not been identified. Although common molecular targets are suggested by recent findings about the role of oncogenes, the mechanism by which the deposition of radiation energy and the formation of adducts or other DNA lesions induced by chemicals affects the changes in the relevant targets may be quite different. The damage to DNA that plays no part in the transformation events, but that influences the stability of the genome, and therefore, the probability of subsequent changes that influence tumorigenesis may be more readily induced by some agents than others. Similarly, the degree of cytotoxic effects that disrupt tissue integrity and increase the probability of expression of initiated cells may be dependent on the type of carcinogen. Also, evidence was presented that repair of the initial lesions could be demonstrated after ...

1984-05-20

350

REVIEW OF EXPLOSIVE (CHEMICAL) FORMING  

Science.gov (United States)

... explosive (shotgun shells, etc.) method of forming is being replaced--for the most part--by the electri- cal discharge and magnetic forming methods. ...

1965-04-01

351

Possible preparation of wood-plastic composites based on unsaturated polyester resins and styrene by radiation and chemical methods in combination  

Energy Technology Data Exchange (ETDEWEB)

Using the radiation chemical method it is possible to prepare wood-plastic composites using doses of 1 to 2.5 kGy. The impregnation mixture in the wood gelatinates and subsequent curing using chemical initiators takes place without outflow of the mixture from the wood and without formation of incrustations. The basic components of the impregnation mixtures used were unsaturated polyester resins; styrene or methyl methacrylate was used as the thinner. The proven initiator of polymerization was 2,2'-azobisisobutyronitrile. The technology is described of wood impregnation and radiation or chemical curing. The effects were monitored of viscosity, temperature, radiation dose and the concentrations of the individual components of the impregnation mixtures and initiators of polymerization on the process of the preparation of wood-plastic composites.

1983-06-01

352

Polycarbonate Bottle Use and Urinary Bisphenol A Concentrations  

UK PubMed Central (United Kingdom)

BackgroundBisphenol A (BPA) is a high-production-volume chemical commonly used in the manufacture of polycarbonate plastic. Low-level concentrations of BPA in animals and possibly...Full Text Available

2009-09-01

353

Poisoning young minds.  

UK PubMed Central (United Kingdom)

For some neurotoxic chemicals, neurobehavioral effects are now considered to be among the most sensitive end points yet detected, particularly if exposures occur during critical windows of vulnerability....Full Text Available

1999-06-01

354

OSHA Hazardous-Chemical Occupational Exposure Standard for laboratories: A new management regulation to ensure employee health. Final report  

Energy Technology Data Exchange (ETDEWEB)

The OSHA's chemical occupational exposure standard for laboratories is an outgrowth of the previously issued Hazard Communication Standard. The standard relieves laboratories from complying with general industry standards but does not require compliance with specific guidelines. The heart of the standard is the creation of a Chemical Hygiene Plan (CHP) in every laboratory. The CHP addresses major issues such as safety equipment and procedures, work practices and training, the designation of a chemical hygiene officer, and the provision of medical consultation and examination for affected employees. This new standard, in effect as of 31 January, 1991, presents yet another regulatory challenge to laboratory managers but also will ensure a safer work environment for laboratory workers.

1991-04-01

355

NSF-NIST Interaction in Chemistry, Materials Research, Molecular Biosciences, Bioengineering and Chemical Engineering  

Science.gov (United States)

NSF-NIST Interaction in Chemistry, Materials Research, Molecular Biosciences, Bioengineering, and ... Laboratory (CSTL). Materials research is centralized in the Materials Science and Engineering ...

356

NASA TECH BRIEF - NASA Technical Report Server (NTRS)  

Science.gov (United States)

(NaMBT) inhibitor in ethylene glycol-water solutions. The improved method must be faster and more accur- ate than wet chemical techniques. ...

357

NASA - NASA Selects Pennsylvania Firm to Build Liquid Nitrogen Plant  

Science.gov (United States)

Sep 21, 2006 ... NASA has selected Air Products and Chemicals, Inc., Allentown, Pa., to design, furnish and install a plant to produce liquid nitrogen for ...

358

Microstructure and properties of ultrafine WC-10Co composites with chemically doped VC  

British Library Electronic Table of Contents (United Kingdom)

Vanadium carbide is the most effective grain growth inhibitor for ultrafine WC-Co composites due to its high solubility and mobility in the cobalt phase at relatively low temperatures; however, there are still some debates over the best way to introduce it into the WC-Co formulation. In this paper, the differences between admixed and chemically doped grain growth inhibitors on the microstructural development and properties of an ultrafine WC-10Co composite are discussed. The densification rate of chemically doped samples is slower in the early stage of sintering and the WC grain sizes of the sintered alloys are finer than those of admixed samples, leading to the increase of hardness and transverse rupture strength of the sintered alloys. The effectiveness of the chemically doped inhibitor ...

2011-01-01

359

Mechanism of action of lenalidomide in hematological malignancies  

UK PubMed Central (United Kingdom)

Immunomodulatory drugs lenalidomide and pomalidomide are synthetic compounds derived by modifying the chemical structure of thalidomide to improve its potency and reduce its side effects. Lenalidomide...Full Text Available

360

Kinetic energy dependence of the reactions of N"+ ions with NO, CO, CO_2, N_2O and SO_2  

International Nuclear Information System (INIS)

... kinetics chemical reactions energy dependence ion-molecule collisions milli

1977-07-01

361

Fourier transform IR studies on the interaction of selected chemicals with isolated cuticles  

International Nuclear Information System (INIS)

It is known that the plant cuticle represents the first barrier that must be overcome by any chemical reaching the plant surface from the atmosphere before entering the plant. Because of the importance of the cuticle as a barrier to penetration of a wide variety of compounds, its morphology, chemistry, and permeability have been extensively studied. However, only limited information is available on the nature of functional chemical groups present and their interaction and role during the penetration process. The usefulness of in situ Fourier transform infrared spectroscopy studies in identifying functional groups present in isolated cuticles is described and their relationships to the structure of the cuticular membrane are discussed. Applications of infrared spectroscopy on the presence and role of phenolics in the cuticle structure and during the cuticle development, nitrogen oxide binding to isolated cuticles, and the interactions between ...

363

Factors Influencing the Effectiveness of Swimming Pool Bactericides  

UK PubMed Central (United Kingdom)

Techniques for culturing, harvesting, and testing bacteria to evaluate bactericidal chemicals for swimming pools are described. Concentrations of 25, 50, and 100 mg of the chlorine stabilizer cyanuric...Full Text Available

1967-05-01

364

Environmental and toxicological aspects of insect growth regulators.  

UK PubMed Central (United Kingdom)

Insect growth regulators (IGRs) are a class of new chemicals that interfere with maturation and reproduction in insects. Proposed hypotheses on the biochemical mechanism of action are presented herein....Full Text Available

1976-04-01

365

Emergencies > Poisoning > Lead Poisoning | Browse EPA Topics...  

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

2011-01-20

366

Emergencies > Oil Spills > Facility Response Plan | Browse EPA...  

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

2011-01-20

367

Emergencies > Emergency Response > September 11 Response | Browse...  

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

2011-01-20

368

Emergencies > Emergency Response > Countermeasures | Browse EPA...  

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

2011-01-20

369

Emergencies > Disasters > Floods | Browse EPA Topics | US EPA  

Science.gov (United States)

Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

2011-01-20

370

ELECTRICAL ACTIVITY IN THE CHEMORECEPTORS OF THE BLOWFLY  

UK PubMed Central (United Kingdom)

The electrical responses of the neurons associated with the various types of chemosensory hairs of the blowfly, Phormia regina Meigen, following stimulation by chemical and mechanical...Full Text Available

1958-11-20

371

Development of Methods for Obtaining Position Image and Chemical Binding Information from Flow Experiments of Porous Media  

Energy Technology Data Exchange (ETDEWEB)

Existing oil reservoirs might be more fully exploited if the properties of the flow of oil and water in porous media were better known. In laboratory experiments it is important to collect as much information as possible to make a descriptive model of the system, including position imaging and chemical binding information. This thesis develops nuclear methods for obtaining position image and chemical binding information from flow experiments of porous media. A combined positron emission tomography and single photon emission computed tomography system to obtain position images, and a time-differential perturbed angular correlation system to obtain chemical binding information, have been built and thoroughly tested. 68 refs., 123 figs., 14 tabs.

1998-12-01

372

Detailed Chemical Kinetic Reaction Mechanisms for Incineration of Organophosphorus and Fluoro-Organophosphorus Compounds  

Energy Technology Data Exchange (ETDEWEB)

A detailed chemical kinetic reaction mechanism is developed to describe incineration of the chemical warfare nerve agent sarin (GB), based on commonly used principles of bond additivity and hierarchical reaction mechanisms. The mechanism is based on previous kinetic models of organophosphorus compounds such as TMP, DMMP and DIMP that are often used as surrogates to predict incineration of GB. Kinetic models of the three surrogates and GB are then used to predict their consumption in a perfectly stirred reactor fueled by natural gas to simulate incineration of these chemicals. Computed results indicate that DIMP is the only one of these surrogates that adequately describes combustion of GB under comparable conditions. The kinetic pathways responsible for these differences in reactivity are identified and discussed. The most important reaction in GB and DIMP that makes them more reactive than TMP or DMMP is found to be a ...

2001-12-13

373
374

Content of hydrogen, helium, and heavy elements in Procyon  

Energy Technology Data Exchange (ETDEWEB)

The values of X = 0.77, Z = 0.035, and Y = 0.195 and the stage of evolution of Procyon are determined from the evolutionary tracks and the results of an analysis of the chemical composition of the atmosphere.

1985-05-01

375

Comparative genomics of insect juvenile hormone biosynthesis?  

UK PubMed Central (United Kingdom)

The biosynthesis of insect juvenile hormone (JH) and its neuroendocrine control are attractive targets for chemical control of insect pests and vectors of disease. To facilitate the molecular...Full Text Available

2006-04-01

376

Chemical versus solvent extraction treatment: Comparison and influence on polyester based bio-composite mechanical properties  

British Library Electronic Table of Contents (United Kingdom)

The influence of chemical and solvent extraction compatibilising techniques on the mechanical properties of poly-lactic acid (PLA) and MaterBi-polyester (PEM) based bio-composites are compared. First, fibres were chemically grafted with two fatty chains: stearic anhydride and octadecylisocyanate. Grafted fibres were characterised by FTIR and elemental analyses. Contact angle measurements show the hydrophobisation of the fibres in spite of very low surface grafting. Extracted and non-grafted fibres were prepared to be used as references. PEM and PLA-based composites with 30% w/w were prepared by compression moulding. Their mechanical properties were studied. It was found that chemical and solvent treatment of the fibres improved the reinforcement effect in the case of a PEM matrix and the Y...

2010-01-01

377

Chemical resistance, void content and tensile properties of oil palm/jute fibre reinforced polymer hybrid composites  

British Library Electronic Table of Contents (United Kingdom)

Tri layer hybrid composites of oil palm empty fruit bunches (EFB) and jute fibres was prepared by keeping oil palm EFB as skin material and jute as the core material and vice versa. The chemical resistance, void content and tensile properties of oil palm EFB/Jute composites was investigated with reference to the relative weight of oil palm EFB/Jute, i.e. 4:1, the fibre loading was optimized and different layering pattern were investigated. It is found from the chemical resistance test that all the composites are resistant to various chemicals. It was observed that marked reduction in void content of hybrid composites in different layering pattern. From the different layering pattern, the tensile properties were slightly higher for the composite having jute as skin and oil palm EFB as core ...

2011-01-01

378

Chemical composition of passive films on AISI 304 stainless steel  

Energy Technology Data Exchange (ETDEWEB)

Chemical characterization of passive films formed on AISI 304 austenitic stainless steel, in a borate/boric acid solution at pH 9.2, under various conditions of potential, temperature, and polarizations time, was made by Auger electron spectroscopy combined with ion sputtering, and x-ray photoelectron spectroscopy (XPS). The depth chemical composition, thickness, and duplex character of the passive layers were determined after processing AES sputter profiles by their quantitative approach based on the sequential layer sputtering model. Moreover, separated contributions of elements in their oxidized and unoxidized state could be disclosed from part to part of the oxide-alloy interface. The XPS study specified the chemical bondings which take placed inside the film, between Fe and oxygen (and water).

1994-12-01

380

Chemical and Biological Warfare: A Manageable Problem  

Science.gov (United States)

... On 20 March 1995, members from the religious cult Aum Shinrikyo released sarin and VX nerve gas into the Tokyo subway system. At the height of ...

2003-01-27

381

Chemical Defense and the Persistence of Pioneer Plant Seeds in the Soil of a Tropical Cloud Forest:  

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT We present evidence that differences in soil seedbank persistence among pioneer plants in the cloud forest of Monteverde, Costa Rica, are influenced by differences in seed chemical defense. We used extracted seed chemicals from Bocconia frutescens (Papaveraceae), Guettarda poasana (Rubiaceae), Phytolacca rivinoides (Phytolaccaceae), Urera elata (Urticaceae), Cecropia polyphlebia (Cecropiaceae), and Witheringia meiantha (Solanaceae) to assess seed chemical defense in two ways: (1) a plant pathogen inhibition assay using Pythium irregulare; and (2) a brine shrimp toxicity assay using Artemia salina. The combined performance of each species in the two assays positively correlated with seedbank persistence. In the pathogen assay, mycelium growth was reduced when Pythium was cultured o...

2007-01-01

382

Big bang nucleosynthesis  

Energy Technology Data Exchange (ETDEWEB)

A brief review of standard big bang nucleosynthesis theory and the related observations of the light element isotopes is presented. Implications of BBN on chemical evolution and constraints on particle properties will also be discussed.

2000-01-01

384

Advances in feedstock recycling offer help with plastic waste  

Energy Technology Data Exchange (ETDEWEB)

An idea whose time has come takes center stage in London this week when BP Chemicals announces details of a consortium of chemical companies joining it in a new recycling project. In the project, which BP has been working on since 1989, waste plastic will be depolymerized to chemical feedstocks, via technology variously called feedstock or chemical recycling, polymer cracking, or tertiary recycling. BP's effort is one of the first to emerge from the research and pilot-plant stages that are committed to actual feedstock recycling of mixed polyolefins and other plastics. But it is only one of the many industry efforts under way to cope with the job of dealing with postconsumer plastics.

1993-10-04

385

Advanced synchronous luminescence system  

Energy Technology Data Exchange (ETDEWEB)

A method and apparatus for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition.

1997-01-01

386

Adducted proteins for identification of endogenous electrophiles.  

UK PubMed Central (United Kingdom)

Chemically reactive compounds in tissues can be monitored through their products of reaction with biomacromolecules. For the purpose of in vivo dose monitoring, hemoglobin (Hb) has been preferred to...Full Text Available

1993-03-01

387

A Model for Chlorine Dioxide Delignification of Chemical Pulp  

British Library Electronic Table of Contents (United Kingdom)

A phenomenon based model for chlorine dioxide delignification of chemical pulp is introduced. The pulp suspension environment is modeled using the concept of two liquid phases, one inside and the other external to the fiber wall. Physico-chemical processes taking place during delignification are implemented with thermodynamic, mass transfer and reaction kinetic models. A broad library of chemical reactions is introduced. Inclusion of each reaction is justified. The model response is tested against experimental laboratory delignification results (o-delignified birch pulp). The experimental data consists of kappa number, hexenuronic acid, inorganic oxy-chlorine compound, and organochlorine (AOX, OX) measurements at several time points during five delignification experiments. The model predic...

2010-01-01

388

A High Throughput Combinatorial Library Technique for Identifying Formalin-Sensitive Epitopes  

UK PubMed Central (United Kingdom)

We present a technique for identifying the amino acids responsible for a loss of immunoreactivity in response to treating an antigen with a chemical modifier. This is of particular interest...Full Text Available

2006-12-20

389

What can we learn about the lipid vesicle structure from the small-angle neutron scattering experiment? (Investigation DMPC vesicle structure by small angle neutron scattering)  

CERN Document Server

Small angle neutron scattering (SANS) on the unilamellar vesicle populations (diameter 500 and 1000 angstrom) was used to characterize lipid vesicles from dimyristoylphosphatidylcholine (DMPC) at three phases (gel, ripple, and liquid). Parameters of vesicle populations and internal structure of the DMPC bilayer were characterized on the basis of the Separated Form Factor (SFF) model. Parameters of the internal bilayer structure (thickness of the membrane and the hydrophobic core, hydration, and surface area of lipid molecule) were determined on the basis of the Hydrophobic-Hydrophilic (HH) approximation of neutron scattering length density across the bilayer r(x) and of the Step Function (SF) approximation of r(x). It was demonstrated in frame of HH approximation that DMPC membrane thickness in liquid phase (T=30 degrees) depends on the membrane curvature. The dependence of the DMPC membrane thickness on temperature was restored from the SANS experiment.

2005-01-01

390

Tris(2,2prime-bipyridyl)ruthenium(II) Electrogenerated Chemiluminescence Sensor Based on Sol-Gel-Derived V2O5/Nafion Composite Films  

British Library Electronic Table of Contents (United Kingdom)

Mesoporous V2O5/Nafion composite films have been used for the immobilization of tris(2,2prime-bipyridyl)ruthenium (II) (Ru(bpy)$\\rm{ {_{3}^{2+}}}$) on an electrode surface to yield a solid-state electrogenerated chemiluminescence (ECL) sensor. The electrochemical and ECL behavior of Ru(bpy)$\\rm{ {_{3}^{2+}}}$ ion-exchanged into the composite films has been characterized as a function of the amount of Nafion incorporated into the V2O5/Nafion composite. The composite film with 80% Nafion content has the largest pore diameter (4.19 nm) and yields the maximum ECL response for tripropylamine (TPA) because of the fast diffusion of analyte into the film with large pores. Due to the enlarged pore size and enhanced conductivity of the V2O5/Nafion composite, the present ECL sensor based on the compo...

2006-01-01

391

The multidrug resistance efflux complex, EmrAB from Escherichia coli forms a dimer in vitro  

International Nuclear Information System (INIS)

Tripartite efflux systems are responsible for the export of toxins across both the inner and outer membranes of Gram negative bacteria. Previous work has indicated that EmrAB-TolC from Escherichia coli is such a tripartite system, comprised of EmrB an MFS transporter, EmrA, a membrane fusion protein and TolC, an outer membrane channel. The whole complex is predicted to form a continuous channel allowing direct export from the cytoplasm to the exterior of the cell. Little is known, however, about the interactions between the individual components of this system. Reconstitution of EmrA + EmrB resulted in co-elution of the two proteins from a gel filtration column indicating formation of the EmrAB complex. Electron microscopic single particle analysis of the reconstituted EmrAB complex revealed the presence of particles approximately 240 x 140 A, likely to correspond to two EmrAB dimers in a back-to-back arrangement, suggesting the dimeric EmrAB form is the ...

2009-03-06

392

The growth factor from plerocercoids of Spirometra mansonoides is both a growth hormone agonist and a cysteine proteinase.  

Science.gov (United States)

Plerocercoids of the tapeworm Spirometra mansonoides produce a substance that stimulates growth of experimental hosts. We report purification of plerocercoid growth factor (PGF) to homogeneity by a process involving isolation and solubilization of plerocercoid membranes, isoelectric point selection by chromatofocusing chromatography or preparative isoelectric focusing, and anion-exchange chromatography. A radioreceptor assay (RRA) for human growth hormone (hGH) was used to detect PGF and purity of the 27.5-kDa protein was judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Proteolytic activity was detected in the 27.5-kDa protein by gelatin substrate PAGE. Characterization of PGF as a neutral cysteine proteinase was based on substrate and inhibitor specificities and dependence on pH and thiol-containing reagents. The association of hGH agonist and proteinase activities was shown by comparing RRA and hydrolytic activities in the presence ...

1996-04-01

393

Systematic implicit solvent coarse-graining of bilayer membranes: lipid and phase transferability of the force field  

International Nuclear Information System (INIS)

We study the lipid and phase transferability of our recently developed systematically coarse-grained solvent-free membrane model. The force field was explicitly parameterized to describe a fluid 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) bilayer at 310 K with correct structure and area per lipid, while gaining at least three orders of magnitude in computational efficiency (see Wang and Deserno 2010 J. Phys. Chem. B 114 11207-20). Here, we show that exchanging CG tails, without any subsequent re-parameterization, creates reliable models of 1,2-dioleoylphosphatidylcholine (DOPC) and 1,2-dipalmitoylphosphatidylcholine (DPPC) lipids in terms of structure and area per lipid. Furthermore, all CG lipids undergo a liquid-gel transition upon cooling, with characteristics like those observed in experiments and all-atom simulations during phase transformation. These studies suggest a promising transferability of our force field parameters to different lipid species and ...

2010-09-01

394

Synthesis, microstructure and photoluminescence of Eu{sup 3+}/Tb{sup 3+} activated Y{sub 2}SiO{sub 5} nanophosphors by new silicate sources  

Energy Technology Data Exchange (ETDEWEB)

Y{sub 2-x}Tb{sub x}SiO{sub 5} and Y{sub 2-x}Eu{sub x}SiO{sub 5} nanophosphors with seven different kinds of silicate sources were synthesized by sol-gel method. The structures have been investigated to be composed of nanometer-size grains of 30-60 nm through X-ray diffraction (XRD) and scanning electron microscopy (SEM) was used to compare the different morphology of patterns from seven different silicon sources. The photoluminescence of Y{sub 2-x}Tb{sub x}SiO{sub 5} was investigated as a function of silicate sources and the results revealed that these nanometer materials showed the characteristic emission {sup 5}D{sub 4} {yields} {sup 7}F{sub J} (J 6, 5, 4, 3) of Tb ions. The characteristic emission {sup 5}D{sub 0} {yields} {sup 7}F{sub J} (J = 1, 2, 4) of Eu ions was also found in the materials of Y{sub 2-x}Eu{sub x}SiO{sub 5}.

2008-01-15

395

Synthesis of nanoporous carbon as a gas adsorbent by reverse replication process of silica template  

Energy Technology Data Exchange (ETDEWEB)

Porous carbon with high surface area and pore volume was prepared by a reverse replication process and its toluene equilibrium adsorption behavior was investigated. The preparation process of the porous carbon was composed of following sub-processes in series: synthesis and template preparation of silica gel, impregnation and polymerization of DVB monomer in silica template, carbonization of DVB polymer in a silica-polymer composite, and HF-assisted selective etching of silica in carbon-silica composite, The prepared porous carbon was nano porous and had ultrahigh specific surface area (2007 m{sup 2}/g) and large pore volume (3.07cm{sup 3}/g). The nanoporous carbon showed rapid toluene adsorption rate and good toluene adsorption capacity, compared with a commercial Y-type zeolite, In the present study, a reverse replication process to prepare nanoporous carbons will be introduced and its application potential as a gas adsorbent will be discussed. (author). 17 ...

2003-06-01

396

Synthesis of (18-/sup 14/C)octatriacontane from (1-/sup 14/C)stearic acid  

Energy Technology Data Exchange (ETDEWEB)

A method was developed to synthesize /sup 14/C-labelled n-alkanes for use in cigarette smoke studies. Specifically, n-(18-/sup 14/C)-octatriacontane was synthesized from 1 mCi (1-/sup 14/C)stearic acid in a radiochemical yield of 20%. The key features of this synthesis were two consecutive alkylations of tosylmethyl isocyanide followed by acid hydrolysis to (18-/sup 14/C)-19-octatriacontanone and modified Wolff-Kishner reduction to the n-alkane. After purification on silica gel 25 mg of (18-/sup 14/C)octatriacontane was obtained with a total radioactivity of 200 ..mu..Ci, a specific activity of 4.3 mCi/mmol, and a radiochemical purity in excess of 98% by thin layer radiochromatography. The method has also been applied to the synthesis of unlabeled n-pentatriacontane and is considered to be generally applicable to the synthesis of radiolabeled alkanes from radiolabeled fatty acids.

1987-01-01

397

Suppressive effects of cadmium on neurons and affected proteins in cultured developing cortical cells  

International Nuclear Information System (INIS)

The purpose of the present study was to examine the in vitro effects of low-dose cadmium (Cd) on developing cortical cells. The cortical cells removed from fetuses (embryonic day 15) were treated with 10 nM of Cd for 24 h. The effects of Cd on dendritic and synaptic development were immunocytochemically observed with anti-microtubule associated protein-2 (MAP2) and anti-synapsin I antibodies, respectively. Administration of Cd suppressed dendritic as well as synaptic development at 10 nM. By two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometric (LC/MS/MS) analysis, we identified three proteins with different expression after Cd-treatment; dihydropyrimidinase-related protein 2 (DRP-2/CRMP-2), 14-3-3-epsillon and calmodulin (CaM). Though the number of identified proteins was small, these proteins are known to be involved in neuronal development. The present study demonstrated the morphological effects as well as affected proteins in ...

2008-11-20

398

Silver nanoparticles directly formed on natural macroporous matrix and their anti-microbial activities  

Energy Technology Data Exchange (ETDEWEB)

In this study, silver nanoparticles were formed on a natural macroporous matrix, the stem of rice-paper plant, by reducing Ag{sup +} in aqueous solution through in situ processing without using any other stabilizers. The pores of the matrix, with their size of about 100 {mu}m, were thought to act as reaction compartments for the nucleation and growth of silver nanoparticles, and the control of nucleation of silver crystal during the reduction reaction was found to be important to the successful formation of nanosized silver particles onto the matrix. The diameter and amount of resultant silver particles can be controlled by changing the reaction conditions. Under optimized conditions, the content of silver particles in the matrix can reach as high as 1.8 wt% with the particle diameters being kept below 100 nm. The anti-microbial activities in terms of minimum inhibitory concentration (MIC) for the silver nanoparticle composites against Escherichia coli and Candida albicans were assayed ...

2007-02-07

399

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

Energy Technology Data Exchange (ETDEWEB)

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 ...

2006-03-01

400

Radiolabeling of oligofructans with CO sub 2 in excised wheat leaves  

Energy Technology Data Exchange (ETDEWEB)

The authors studied the flow of carbon ({sup 14}C) from CO{sub 2} through sucrose to oligofructans in wheat (Triticum aestivum L.) leaves that had been induced by excision to accumulate fructan. Leaves were either labeled for 30 min and then chased in ambient air for 2 h or labeled continuously for 2 h. Fructans were chromatographed on BioGel P2 column. During continuous labeling, the specific activity was highest in sucrose and decreased for fructans with DP 3 to 5, and each increased linearly with time for 2 h. During the chase period, sucrose specific activity increased for 60 min and then declined while oligofructans gained in specific activity through the 2 h period. After 30 min of labeling, the specific activity of fructose moiety of sucrose was equal to glucose but, in oligofructans, those of the individual fructose units were not. The results may provide insight into the fructosyl donor-acceptor pool relations in wheat leaves.

1989-04-01

401

Radioiodination of chicken luteinizing hormone without affecting receptor binding potency  

Energy Technology Data Exchange (ETDEWEB)

By improving the currently used lactoperoxidase method, we were able to obtain radioiodinated chicken luteinizing hormone (LH) that shows high specific binding and low nonspecific binding to a crude plasma membrane fraction of testicular cells of the domestic fowl and the Japanese quail, and to the ovarian granulosa cells of the Japanese quail. The change we made from the original method consisted of (1) using chicken LH for radioiodination that was not only highly purified but also retained a high receptor binding potency; (2) controlling the level of incorporation of radioiodine into chicken LH molecules by employing a short reaction time and low temperature; and (3) fractionating radioiodinated chicken LH further by gel filtration using high-performance liquid chromatography. Specific radioactivity of the final {sup 125}I-labeled chicken LH preparation was 14 microCi/micrograms. When specific binding was 12-16%, nonspecific binding was as low as 2-4% in the ...

1989-12-01

402

Radiation resistance of nylon. [Gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

Various nylons including nylon 6, nylon 66, nylon 610 and nylon 12 in the forms of fiber and film were irradiated with the gamma-ray from Co-60 at the dose rate of 0.12 Mrad/hr in the atmosphere of oxygen at 7 kg/cm/sup 2/ and at the room temperature. The irradiation in vacuum on the same specimens was performed at 0.5 Mrad/hr. The tensile properties and the gel fraction of the irradiated nylon samples were measured, and the radiation resistance of the nylons against the irradiation at low dose rate was estimated. From the experimental results, it became clear that in the case of irradiation in vacuum, all the nylons were durable to the irradiation of 250 Mrad or more, and nylon 6 was more durable than nylon 12, and in the case of irradiation in pressurized oxygen, the radiation resistance of the nylons decreased to one-tenth as compared with that in vacuum, and contrary to that in vacuum, nylon 12 was superior to nylon 6, while nylon 610 was intermediate. From ...

1983-12-01

403

Purification and characterization of four keratinases produced by Streptomyces sp. strain 16 in native human foot skin medium  

British Library Electronic Table of Contents (United Kingdom)

Four extracellular keratinases (designated KI, KII, KIII, and KIV) were produced during submerged aerobic cultivation in a medium containing native human foot skin (NHFS) for enzyme synthesis. The molecular weights, determined by SDS-PAGE, were 25, 50, 34, and 19kDa, respectively. Gel filtration of the four purified enzymes in native conditions indicated that active keratinase KI is a novel homo-octamer, KII a homo-dimer, and KIII and KIV monomers. All four keratinases exhibited high activities at pH 8.0-10.0 with an optimal pH of 9.0. The optimal temperature for keratinolytic activity of KI, KII, and KIII was approximately 50, and 60degreeC for KIV. One millimolar of PMSF completely inhibited the keratinolytic activities of the four enzymes. The N-terminal sequences of KI, KII, and KIII s...

2010-01-01

404

Proteomic Analysis of Proteins Secreted by HepG2 Cells Treated with Butyl Benzyl Phthalate  

British Library Electronic Table of Contents (United Kingdom)

Proteomic changes in proteins secreted by human hepatocellular carcinomas (HepG2) cells exposed to butyl benzyl phthalate (BBP) were evaluated. HepG2 cells were treated with three different concentrations of BBP (0, 10, or 25 ?M) for 24 or 48 h. Following incubation, the cells were subjected to proteomic analysis using two different pI ranges (4-7 and 6-9) and large-size two-dimensional gel electrophoresis. Results showed resolution of a total of 2776 protein spots. Of these, 29, including 19 upregulated and 10 downregulated proteins, were identified by electrospray ionization-mass spectrometry-mass spectrometry (ESI-MS/MS). Among these, the identities of cystatin C, Rho guanine nucleotide dissociation inhibitor, gelsolin, DEK protein, Raf kinase inhibitory protein, triose phosphate ...

2010-01-01

405

Preparation and characterization of Co-doped BaTiO{sub 3} nanosized powders and ceramics  

Energy Technology Data Exchange (ETDEWEB)

The Co-doped BaTiO{sub 3} nanosized powders and ceramics were prepared via the sol-gel process. The powders and ceramics were characterized by methods of XRD, SEM and TEM. The dielectric properties of the ceramics were also determined by these methods. The influence of sintering temperature, sintering time and Co concentration on the microstructure and dielectric properties was discussed. The results revealed that the powders were in nanometer scale (30-50 nm) and were mainly composed of cubic BaTiO{sub 3} phase and small amount of BaCO{sub 3}. After sintering, both the cubic BaTiO{sub 3} and BaCO{sub 3} were transformed into tetrahedron BaTiO{sub 3}. The sintering temperatures of the Co-doped BaTiO{sub 3} ceramics decreased (about 100 deg. C) and the Curie temperatures of the ceramics were then moved to lower temperature. In addition, the dielectric constant of the ceramics doping with Co was higher than that of the pure BaTiO{sub 3} ceramics. The dielectric ...

2006-08-25

406

Photocatalytic self-cleaning properties of cellulosic fibers modified by nano-sized zinc oxide  

International Nuclear Information System (INIS)

Nano-sized zinc oxide was synthesized and deposited onto cellulosic fibers using the sol-gel process at ambient temperature. The prepared materials were characterized using several techniques including scanning electron microscopy, transmission electron microscopy, diffuse reflectance spectroscopy, X-ray diffraction and thermogravimetric analysis. X-ray diffraction studies of the ZnO-coated fiber indicate formation of the hexagonal crystal phase which was satisfactory crystallized on the fiber surface. The electron micrographs show formation of zinc oxide nanoparticles within 10-15 nm in size which have been homogeneously dispersed on the fiber surface. The prepared materials show significant photocatalytic self-cleaning activity, which was monitored by diffuse reflectance spectroscopy. The photoactivity was studied upon measuring the photodegradation of methylene blue and eosin yellowish under UV-Vis irradiation. The photocatalytic activity of the treated fabrics ...

2011-03-31

407

New real-time MR image-guided surgical robotic system for minimally invasive precision surgery  

Energy Technology Data Exchange (ETDEWEB)

To investigate the usefulness of a newly developed magnetic resonance (MR) image-guided surgical robotic system for minimally invasive laparoscopic surgery. The system consists of MR image guidance [interactive scan control (ISC) imaging, three-dimensional (3-D) navigation, and preoperative planning], an MR-compatible operating table, and an MR-compatible master-slave surgical manipulator that can enter the MR gantry. Using this system, we performed in vivo experiments with MR image-guided laparoscopic puncture on three pigs. We used a mimic tumor made of agarose gel and with a diameter of approximately 2 cm. All procedures were successfully performed. The operator only advanced the probe along the guidance device of the manipulator, which was adjusted on the basis of the preoperative plan, and punctured the target while maintaining the operative field using robotic forceps. The position of the probe was monitored continuously with 3-D navigation and 2-D ISC ...

2008-04-15

408

Metal coordination and selectivity with oxine ligands bound to silica polyamine composites  

British Library Electronic Table of Contents (United Kingdom)

A series of oxine ligands, 5-X, 8 OH C9H6N (X = H, Cl, SO3H) have been covalently bound to a silica gel polyamine composite made from a silanized amorphous silica xerogel and poly(allylamine) (BP-1) by the Mannich reaction. The resulting modified composites WP-4(X = H), CB-1(X = Cl), and SB-1(X = SO3H) were characterized by elemental analysis, FTIR, and solid state CPMAS-13C-NMR. Using the analytical data before and after the ligand modification, the ligand loading could be estimated and in combination with metal ion capacities a metal to ligand ratio could be obtained. The composites WP-4 and CB-1 both showed ratios of approximately 1 : 1 while the sulfonate modified composite, SB-1, showed a metal to ligand ratio of 1 : 2. This is tentatively interpreted in terms of a zwitterionic oxine ...

2010-01-01

409

Interaction of thyroid hormone and hemoglobin: nature of the interaction and effect of hemoglobin on thyroid hormone radioimmunoassay  

International Nuclear Information System (INIS)

Gel filtration of human erythrocyte (RBC) lysate incubated with labeled thyroxine (Tu) or triiodothyronine (Tt) revealed co-elution of a major iodothyronine-binding fraction (R-2) and hemoglobin. Solutions of purified human hemoglobin and Tt also showed co-elution of hormone and hemoglobin. Because hematin and protoporphyrin were shown to bind labeled Tt, the oxygen-binding site on hemoglobin was excluded as the site of iodothyronine-hemoglobin interaction. Analysis of hormone binding by heme and globin moieties showed Tt binding to be limited to the heme fraction. Addition of excess unlabeled Tt to hemoglobin or heme incubated with labeled Tt indicated 75% to 90% of hormone binding was poorly dissociable. These observations suggested that the presence of hemoglobin in RBC lysate or in serum could influence the measurement of Tu and Tt by specific radioimmunoassay (RIA). Subsequent studies of the addition to serum of human hemoglobin revealed a significant ...

410

Influence of crystallization on the spectral features of nano-sized ferroelectric barium strontium titanate (Ba0.7Sr0.3Tio3) thin films  

British Library Electronic Table of Contents (United Kingdom)

Ferroelectric barium strontium titanate (Ba0.7Sr0.3TiO3)(BST) thin films have been prepared from barium 2-ethylhexanoate [Ba[CH3(CH2)3CH(C2H5)CO2]2], strontium 2-ethylhexanoate [Sr[CH3(CH2)3CH(C2H5)CO2]2] and titanium(IV) isopropoxide [TiOCH(CH3)2]4 precursors using a modified sol-gel technique. The precursor except [TiOCH(CH3)2]4 were synthesized in the laboratory. Transparent and crack-free films were fabricated on pre-cleaned quartz substrates by spin coating. The structural and optical properties of films annealed at different temperatures have been investigated. The as-fired films were found to be amorphous that crystallized to the tetragonal phase after annealing at 550degreeC for 1h in air. The lattice constants "a" and "c" were found to be 3.974A and 3.990A, respectively. The grain...

2008-01-01

411

In situ ellipsometric studies of formation kinetics of rare earth metal conversion coatings on magnesium alloy  

International Nuclear Information System (INIS)

In situ spectroscopic ellipsometry was employed to investigate the initial regime of rare earth metal (REM) conversion coatings formation on AZ31 magnesium alloy. Three REM salts solutions, 0.05 mol.dm"-"3 Ce(NO_3)_3, La(NO)_3 and Sm(NO)_3 solutions, were used for REM conversion coatings preparation. By deconvoluting the ellipsometric data, the surface of the fresh well-polished AZ31 magnesium alloy was found to be covered with 15.80 nm thick native (hydr)oxide film; the refractive indices and the thickness of Ce, La and Sm conversion coatings were obtained. The formation kinetics of three REM coatings follows different exponential functions and the coatings exhibit different optical properties. La conversion coating has the largest n values and the lowest k values while Sm conversion coating is just opposite. Moreover, the pH variation of the bulk conversion solutions upon the coatings formation was recorded. It is confirmed that the reduction of protons leads to the interfacial pH ...

2008-05-01

412

Improvement of a high-resolution pulse cold neutron spectrometer AGNES  

International Nuclear Information System (INIS)

AGNES is a chopper spectrometer installed at the top of the C3 cold guide of JRR-3 (JAERI, Tokai). In 2004 - 2006, this spectrometer was greatly improved by installing (1) 208 new detectors to make the detector bank complete, (2) new radiation shields composed of Fe (14 mm), polyethylene (50 mm), B4C rubber (10 mm), and Cd (0.5 mm) sheets, (3) a new control system for the anti-frame-overlap chopper rotating simultaneously with the Fermi chopper, (4) a monitor counter at the space between the chopper and monochromator, (5) a neutron guide tube (50 cm) before the monochromator, (6) a new instrument control (monochromators, choppers, beam narrowers, etc.) and measurement control (real-time data monitoring, sample temperature control, etc.) systems, (7) a top-loading type cryostat workable at a wide temperature range of 6 - 480 K. As the results of these improvements, the signal intensity has been increased by 3.3 and the background has been reduced by 1/10 both compared with the data ...

2007-01-01

413

High-performance hybrid pervaporation membranes with superior hydrothermal and acid stability  

Energy Technology Data Exchange (ETDEWEB)

A new organic-inorganic hybrid membrane has been prepared with exceptional performance in dewatering applications. The only precursor used in the sol-gel synthesis of the selective layer was organically linked 1,2-bis(triethoxysilyl)ethane (BTESE). The microporous structure of this layer enables selective molecular sieving of small molecules from larger ones. In the dehydration of n-butanol with 5% of water, the membrane shows a high separation factor of over 4000 and ultra-fast water transport at a rate of more than 20 kg m{sup -2} h{sup -1} at 150C. This can be related to the high adsorption capacity of the material and the sub-micron thickness of the selective layer. The selectivity has now remained constant over almost one and a half years under continuous process testing conditions. Apart from the hydrothermal stability, the membrane exhibits a high tolerance for acid contamination. A slow performance decline in flux and separation factor is only observed at a ...

2009-05-15

414

FMRFamide-like immunoreactivity in rat brain: development of a radioimmunoassay and its application in studies of distribution and chromatographic properties  

International Nuclear Information System (INIS)

A radioimmunoassay is described for the molluscan neuropeptide, Phe-Met-Arg-Phe-NH"2(FMRFamide). The antibody used is C-terminal-specific and shows slight but significant (1-2%) cross-reactivity with chicken pancreatic polypeptide (APP). The assay has been used to identify in rat brain extracts a pair of molecules that may represent mammalian counterparts of FMRFamide. Their concentrations were highest in spinal cord and hypothalamus (>10 pmol.g"-_1) and lowest in cerebellum and striatum (<3.5 pmol.g"-_1). The two immunoreactive peptides were separated on CM ion-exchange chromatography where they appeared to be less basic than FMRFamide. On Sephadex G50 gel filtration one eluted in a similar position to FMRFamide and the other slightly earlier suggesting it may be of higher molecular weight. The rat immunoreactive components do not correspond to previously described neuropeptides or hormones, and may be members of a new group of mammalian neuropeptides with ...

415

Experimental studies on reconstruction of peripheral arteries by high voltage cathode ray irradiated allografts  

International Nuclear Information System (INIS)

The use of cathode ray irradiated arterial allografts on the reconstruction of small peripheral arteries is described. The fate of irradiated arterial allografts implanted subcutaneously in rats was compared histologically with that of allografts which were fresh, frozen or stored in 70% alcohol. Follow-up studies were made of 10 dogs in which irradiated arterial allografts had been implanted in the femoral artery to be evaluated; long term patency by arteriography, gross and histologic changes of the implanted allografts, and the luminal surface of the implanted allografts by scanning electron microscopic studies. For the purpose of antigenic studies, extracts of canine arteries which had been irradiated, frozen or stored in 70% alcohol, were prepared and tested by the following immunological methods: precipitation, Ouchterlony gel diffusion, and passive cutaneous anaphylaxis. From the results obtained in these experiments, it was concluded that, compared with ...

1976-01-01

416

Effects of freeze-thaw cycles on the performance of soft materials used in soil covers with capillary barrier; Effets des cycles de gel-degel sur la performance des materiaux meubles utilises dans les couvertures a effets de barriere capillaire  

Energy Technology Data Exchange (ETDEWEB)

Freezing and thaw have an effect on soils, and the effect of the freeze-thaw cycle on soil covers used in the control of acid mine drainage was discussed in this poster presentation. The purpose of soil covers in cases involving acid mine drainage (AMD) is to reduce the exposure of tailings to oxygen which cause AMD. The effect of this freezing-thaw cycle on soft materials used in soil covers with capillary effect was studied. Some laboratory experiments were conducted to evaluate the properties of the moisture retention layer. The preliminary results were presented. The results indicated that the freeze-thaw cycle might affect the performance of soil covers in the long term, depending on the type of materials selected. Further research is undergoing. 26 figs.

2000-07-01

417

Effect of radiation dose on the properties of natural rubber nanocomposite  

Energy Technology Data Exchange (ETDEWEB)

Effect of radiation dose and carbon nanotubes (CNT) on the mechanical properties of standard Malaysian rubber (SMR) was investigated in this study. SMR nanocomposites containing 1-7 phr CNT were prepared using the solvent casting method and the nanocomposites were radiated at doses of 50-200 kGy. The change in mechanical properties, especially, tensile strength (Ts), elongation at break (Eb), hardness and tensile modulus at 100% elongation (M{sub 100}) were studied as a function of radiation dose. The structure and morphology of reinforced natural rubber was investigated by FESEM, TEM and AFM in order to gain further evidence on the radiation-induced crosslinking. It was found that the Ts, M{sub 100} and the hardness of the SMR/CNT nanocomposites significantly increased with radiation dose; the elongation at break exhibited an increase up to 100 kGy, and a downward trend thereafter. Results on gel fraction further confirmed the crosslinking of SMR/CNT ...

2010-12-15

418

Differentiation to adipocytes in accompanied by an increase in the amounts of Gi- and Go-proteins in 3T3-L1 cells  

International Nuclear Information System (INIS)

Treatment of cultures of 3T3-L1 cells with methylisobutyl-xanthine and dexamethasone has been shown to result in accumulation of lipid and conversion to the morphology of adipocytes in more than 90% of the cells. The status of the stimulatory (Gs), inhibitory (Gi) and Go-proteins during the course of 3T3-L1 differentiation was examined. The amount of alpha subunit of Gs (#alpha#Gs), assayed by radiolabeling in the presence of cholera toxin and ["3"2P]NAD"+, increased upon differentiation as previously described by others. The amounts of #alpha#Gi and #alpha#Go assayed by radiolabeling in the presence of pertussis toxin and ["3"2P]NAD"+ increased 3-fold upon differentiation. Immunoblots of cell membranes subjected to gel electrophoresis in sodium dodecyl sulfate were probed with two rabbit antisera raised against bovine brain #alpha#Go and with one raised against the#beta#-subunit of the bovine rod-outer-segment G-protein, referred to as transducin. The ...

1986-06-08

419

Detection by /sup 125/I-cationized cytochrome c of proteoglycans and glycosaminoglycans immobilized on unmodified and on positively charged nylon 66  

Energy Technology Data Exchange (ETDEWEB)

We have examined the detection by a /sup 125/I-labeled basic protein, cationized cytochrome c, of selected proteoglycans (PGs) and standard preparations of glycosaminoglycans (GAGs) immobilized on Nylon 66 and also on positively charged Nylon 66. Immobilization on Nylon 66 appears to allow a relative freedom of interaction between PGs or GAGs and /sup 125/I-cationized cytochrome c, but a more restricted reaction was observed when PGs and GAGs were immobilized to positively charged Nylon 66. On this support PGs with large numbers of GAG side chains reacted well with /sup 125/I-cationized cytochrome c, but GAGs were minimally reactive. By taking advantage of some of the properties of large-pore agarose-acrylamide gels, rapid partial characterization of some PGs can be accomplished in the 10-ng range, and therefore at a sensitivity equal to PGs with internal biosynthetic labels.

1987-09-01

420

DNA alterations photosensitized by tetracycline and some of its derivatives  

Energy Technology Data Exchange (ETDEWEB)

Bacteriophage M13 mp10 DNA were irradiated with near-UV light in the presence of tetracycline derivatives and primed with synthetic oligonucleotide to be used for DNA synthesis using Escherichia coli DNA polymerase. Chain terminations were observed by denaturing polyacrylamide gel electrophoresis and mapped precisely. All the synthesis stops occurred before or at the level of guanine residues, showing that the photoreaction mediated by tetracycline derivatives led to a preferential alteration of guanine residues. These lesions were demonstrated to be induced in DNA through a pathway involving singlet oxygen. Tetracycline derivatives also photoinduced the breakage of the DNA sugar-phosphate backbone monitored by the conversion of supercoiled phi X174 DNA to a relaxed form. This lesion was shown to be initiated by hydroxyl radicals. The production of this free radical has been confirmed by electron paramagnetic resonance (EPR) spin trapping experiments using ...

1986-06-01

421

Construction of a human MluI YAC library  

Energy Technology Data Exchange (ETDEWEB)

The authors describe a cloning strategy for the construction of a human genomic library in yeast artificial chromosomes (YACs) based on complete digestion of high-molecular-weight DNA with the infrequently cutting restriction enzyme MluI. Cloning of MluI fragments in the vector pYAC-RC and one subsequent size fractionation by preparative pulsed-field gel electrophoresis yielded a library with average insert sizes of 600 kb. Ninety-seven percent of the colonies were recombinant. An additional size fractionation of MluI fragments prior to ligation had no significant influence on the size of the YACs. The library currently consists of 5000 clones, which is the equivalent of one human genome. Nineteen percent of the YACs were larger than 1.2 Mb. Since smaller MluI fragments are lost during sizing, they also performed cloning without size fractionation. Only 20% of the colonies were recombinant, probably due to unligated vector fragments that were present during the ...

1994-05-01

422

Cloning and linkage mapping of three polymorphic tetranucleotide (TAAA)[sub n] repeats on human chromosome 21  

Energy Technology Data Exchange (ETDEWEB)

The authors report the cloning, sequencing, and mapping of three short sequence repeat polymorphisms due to tetranucleotide (TAAA) repeats from human chromosome 21. These DNA markers (D21S221, D21S225, D21S226) have been cloned from the chromosome 21-specific plasmid library of J. C. Fuscoe, C. C. Collins, D. Pinkel, and J. W. Gray and were shown to be polymorphic by polymerase chain reaction amplification and polyacrylamide gel electrophoresis. Genotypes were determined in informative CEPH pedigrees and used in linkage analysis relative to other mapped markers on human chromosome 21. One of these markers, D21S221, is closely linked to the amyloid precursor protein gene (APP), which has been implicated in the etiology of familial Alzheimer disease in some families. 18 refs., 3 figs., 2 tabs.

1992-12-01

423

Clinical biochemistry of aluminum  

Energy Technology Data Exchange (ETDEWEB)

Aluminum toxicity has been implicated in the pathogenesis of a number of clinical disorders in patients with chronic renal failure on long-term intermittent hemodialysis treatment. The predominant disorders have been those involving either bone (osteomalacic dialysis osteodystrophy) or brain (dialysis encephalopathy). In nonuremic patients, an increased brain aluminum concentration has been implicated as a neurotoxic agent in the pathogenesis of Alzheimer's disease and was associated with experimental neurofibrillary degeneration in animals. The brain aluminum concentrations of patients dying with the syndrome of dialysis encephalopathy (dialysis dementia) are significantly higher than in dialyzed patients without the syndrome and in nondialyzed patients. Two potential sources for the increased tissue content of aluminum in patients on hemodialysis have been proposed: (1) intestinal absorption from aluminum containing phosphate-binding gels, and (2) ...

1981-05-01

424

Characterization of mal recombination plasmids cloned in Streptococcus pneumoniae  

Energy Technology Data Exchange (ETDEWEB)

The malM locus of Streptococcus pneumoniae was cloned into one of the two PstI sites of the multicopy S. pneumoniae plasmid pMV158. To eliminate chromosomal transformants in the simultaneous selection for tetracycline resistance (coded by pMV158) and maltose utilization, the host cells contained a chromosomal deletion of the mal gene cluster. Two clones were isolated; one with a 3.3 kb insert (pLS70) which behaved like wild type with respect to maltose utilization, and another with a 2.9 kb insert (pLS69) which behaved as though it contained a down promoter mutation. Preliminary mapping of these clones by restriction analysis placed the 0.4kb deletion on a HindIII fragment in the interior of the chromosomal insert. The recombinant plasmids were able to transform over 50% of a recipient population to Mal/sup +/. Enzyme measurements of the clones indicated an overproduction of amylomaltase, constituting up to 10% of the total cellular protein, and supported the theory that the deletion ...

1981-01-01

425

Characterization of hydrophobic ionic liquid-carbon nanotubes-gold nanoparticles composite film coated electrode and the simultaneous voltammetric determination of guanine and adenine  

Energy Technology Data Exchange (ETDEWEB)

A novel composite film, comprising of hydrophobic ionic liquid (IL), multi-walled carbon nanotubes (MWNTs) and gold nanoparticles (GNP), was fabricated and characterized. The GNP was introduced through electrochemical deposition on IL-MWNT gel film coated glassy carbon electrodes (GCE). Experiments showed that both IL and MWNTs could facilitate the GNP deposition. With GNP the composite film exhibited smaller electron transfer resistance and higher sensitivity in sensing guanine (G) and adenine (A). Under the optimized experimental conditions, the anodic peak currents were linear to the analyte concentration in the ranges of 0.008-2.0 {mu}M. The detection limits were down to nanomole level after an accumulation of 150 s on open-circuit. In addition, on the composite film coated GCE, the anodic peaks of G and A were well separated, and their response sensitivities kept almost unchanged no matter whether they coexisted or not. This proposed procedure was successfully ...

2008-11-01

426

Characterization of hydrophobic ionic liquid-carbon nanotubes-gold nanoparticles composite film coated electrode and the simultaneous voltammetric determination of guanine and adenine  

International Nuclear Information System (INIS)

A novel composite film, comprising of hydrophobic ionic liquid (IL), multi-walled carbon nanotubes (MWNTs) and gold nanoparticles (GNP), was fabricated and characterized. The GNP was introduced through electrochemical deposition on IL-MWNT gel film coated glassy carbon electrodes (GCE). Experiments showed that both IL and MWNTs could facilitate the GNP deposition. With GNP the composite film exhibited smaller electron transfer resistance and higher sensitivity in sensing guanine (G) and adenine (A). Under the optimized experimental conditions, the anodic peak currents were linear to the analyte concentration in the ranges of 0.008-2.0 ?M. The detection limits were down to nanomole level after an accumulation of 150 s on open-circuit. In addition, on the composite film coated GCE, the anodic peaks of G and A were well separated, and their response sensitivities kept almost unchanged no matter whether they coexisted or not. This proposed procedure was successfully ...

2008-11-01

427

Characterisation of polynuclear aromatic sulfur-heterocycles in a coal extract by GC/MS  

Energy Technology Data Exchange (ETDEWEB)

Polynuclear aromatic sulphur heterocycles (PASHs) were isolated from a coal extract by two-step separation method using silica gel column chromatography and ligand exchanges thin layer chromatography (PdCl{sub 2}/SiO{sub 2}). The subfraction was examined by capillary column gas chromatography with flame ionization detector and flame photometric detector and gas chromatography - mass spectrometry. Identification was accomplished by comparison of chromatographic retention indices and mass spectra of compounds with those reported in the literature. It was found that the principal structures of the sulphur-containing fraction of Guiding coal extract have 3-4 aromatic rings. Dibenzothiophene, C{sub 1} - C{sub 3} alkylated dibenzothiophenes, benzonaphthothiophene and its alkylated derivatives were the main compounds. Only a few other polynuclear sulfur heterocycles were detected. No benzothiophene and its derivatives were presented. 8 refs., 2 figs., 3 tabs.

1994-06-01

428

Cerebral biochemical abnormalities in experimental maternal phenylketonuria: gangliosides and sialoglycoproteins  

International Nuclear Information System (INIS)

The present study sought a biochemical explanation for retarded brain development in the heterozygous offspring of the phenylketonuric (PKU) mother. Two rat models of simulated maternal PKU, one induced by p-chloropheylalanine and phenylalanine and the other by phenylacetate, were employed in this investigation. Maternal PKU had no influence on cerebral concentrations of DNA, protein, and cholesterol, which were normal in the 2 d old pup. However, there was a noticeable disruption of the normal ganglioside pattern and a significant reduction of sialoglycoproteins. Concomitant with a delayed drop in the gangliosides Q/sub 1b/ and D_3, was a slower rise in M_1 and D/sub 1a/. At least 66% of sialoglycoproteins located on SDS-PAGE gel chromatograms, by radioactivity incorporated in vivo from radiolabeled N-acetylmannosamine and by ("3H) sialic acid released by neuraminidase from periodate-("3H) borohydride labeled glycoproteins, have mobilites of the cell adhesion ...

429

Biosorption of copper (II) onto immobilized cells of Pycnoporus sanguineus from aqueous solution: Equilibrium and kinetic studies  

Energy Technology Data Exchange (ETDEWEB)

The ability of white-rot fungus, Pycnoporus sanguineus to adsorb copper (II) ions from aqueous solution is investigated in a batch system. The live fungus cells were immobilized into Ca-alginate gel to study the influence of pH, initial metal ions concentration, biomass loading and temperature on the biosorption capacity. The optimum uptake of Cu (II) ions was observed at pH 5 with a value of 2.76 mg/g. Biosorption equilibrium data were best described by Langmuir isotherm model followed by Redlich-Peterson and Freundlich models, respectively. The biosorption kinetics followed the pseudo-second order and intraparticle diffusion equations. The thermodynamic parameters enthalpy change (10.16 kJ/mol) and entropy change (33.78 J/mol K) were determined from the biosorption equilibrium data. The FTIR analysis showed that -OH, -NH, C-H, C=O, -COOH and C-N groups were involved in the biosorption of Cu (II) ions onto immobilized cells of P. sanguineus. The immobilized cells ...

2009-01-15

430

A study of membrane protein defects and alpha hemoglobin chains of red blood cells in human beta thalassemia  

International Nuclear Information System (INIS)

The soluble pool of alpha hemoglobin chains present in blood or bone marrow cells was measured with a new affinity method using a specific probe, beta A hemoglobin chain labeled with ["3H]N-ethylmaleimide. This pool of soluble alpha chains was 0.067 #+-# 0.017% of hemoglobin in blood of normal adult, 0.11 #+-# 0.03% in heterozygous beta thalassemia and ranged from 0.26 to 1.30% in homozygous beta thalassemia intermedia. This elevated pool of soluble alpha chains observed in human beta thalassemia intermedia decreased 33-fold from a value of 10% of total hemoglobin in bone marrow cells to 0.3% in the most dense red blood cells. The amount of insoluble alpha chains was measured by using the polyacrylamide gel electrophoresis in urea and Triton X-100. In beta thalassemia intermedia the amount of insoluble alpha chains was correlated with the decreased spectrin content of red cell membrane and was associated with a decrease in ankyrin and with other abnormalities of ...

431

A new kind of immobilized lipase in organic solvent and its structure model.  

Science.gov (United States)

In this paper, we used Ca-alginate gel beads coated with polyetheneimine and glutaraldehyde to adsorb Expansum penicillium lipase. The immobilized lipase catalyzed esterification of 1-dodecanol with dodecanoic acid in benzene. The results show that when the concentration of Ca-alginate, polyetheneimine (PEI) and glutaraldehyde is 1%, 6% and 1%, respectively, the activity of the immobilized lipase and the amount of adsorbed protein are the highest. The immobilized lipase is better than the SDS-immobilized lipase. The activity of the immobilized lipase connected by glutaraldehyde is higher than the activity of that without glutaraldehyde. The initial rate of the immobilized lipase and lyophilized lipase powder is 5.9 x 10(2) nmol/min.mgpr and 2.8 x 10(1) nmol/min.mgpr, respectively. After the immobilized lipase catalyzed the esterification reaction at 37 degrees C for about 12 hours, 93.3% of 1-dodecanol was converted to ester, but for lyophilized lipase powder, only ...

1994-04-15

432

Sol-gel synthesis of high-quality SrRuO{sub 3} thin film electrodes suppressing the formation of detrimental RuO{sub 2} and the dielectric properties of integrated lead lanthanum zirconate titanate films.  

Science.gov (United States)

A facile solution chemistry is demonstrated to fabricate high-quality polycrystalline strontium ruthenium oxide (SrRuO{sub 3}) thin film electrodes on silicon substrates suppressing the formation of undesired ruthenium oxide (RuO{sub 2}) for the deposition of dielectric and ferroelectric materials like lead lanthanum zirconate titanate (PLZT). The robust, highly crystalline SrRuO{sub 3} film fabrication process does not favor the formation of RuO{sub 2} because of molecular level modification of the precursors possessing analogous melting points, yielding homogeneous films. This chemistry is further understood and complemented by kinetic and thermodynamic analysis of the DTA data under nonisothermal conditions, with which the activation energies to form RuO{sub 2} and SrRuO{sub 3} were calculated to be 156 {+-} 17 and 96 {+-} 10 kJ/mol, respectively. The room-temperature resistivity of the SrRuO{sub 3} film was measured to be 850 {+-} 50 {mu}{Omega} cm on silicon (100) substrates. The ...

2011-01-01

433

Monitoring of DNA and cytogenetic damage in lymphocytes from persons with skin cancer diseases  

International Nuclear Information System (INIS)

There is a lot of interest in the studies that would help to understand whether there is a casual association between cancer and various types of molecular or cytogenetic damage detected in human cells. One major oncogenesis process is activation of proto-oncogenes by point mutations or chromosomal translocation. There are substantial evidence that indicates that the loss of heterozygosity of certain chromosomes is involved in human cancerogenesis. Our study aimed to elicit the possible association between cancer and DNA and cytogenetic abnormalities induced in lymphocytes of people bearing various categories of skin cancer cells. Fresh blood was collected by venipuncture from 25 individuals (including nine prior to cancer treatment). All patients were nonsmoking males, however 42.3 % of them were former smokers. Blood samples were divided into two parts and in the first part of samples cytogenetic studies were performed immediately, while from the second part lymphocytes were isolated ...

2004-11-01

434

Effect of chlordecone (kepone) on calcium transport mechanisms in rat heart sarcoplasmic reticulum  

Energy Technology Data Exchange (ETDEWEB)

Since chlordecone (Kepone, CD) interferes with cardiac Na{sup +} ion translocases, we have studied CD effects on cardiac SR calcium pump activity. SR was isolated from heart ventricles of male Sprague-Dawley rats. Cardiac SR Ca{sup 2+}-ATPase, {sup 45}Ca-uptake and cAMP as well as calmodulin (CaM) dependent protein phosphorylation were measured. Ca{sup 2+}-ATPase was differentiated into low affinity and high affinity forms by measuring the activity using 50 and 0.7 {mu}M free Ca{sup 2+} respectively. CD in vitro inhibited {sup 45}Ca-uptake by SR in a concentration dependent manner with an IC50 value of 7 {mu}M and SR {sup 45}Ca-uptake was totally inhibited at 20-30 {mu}M CD. In agreement with this, both high affinity and low affinity Ca{sup 2+}-ATPases, which are involved in Ca{sup 2+} transport across membranes, were also inhibited by CD in a concentration dependent manner with IC50 values of 0.7 and 3.2 {mu}M respectively. Both Ca{sup 2+}-ATPase and {sup 45}Ca-uptake by cardiac SR ...

1990-01-01

435

Water chemistry and corrosion in water-steam circuits of nuclear power plants  

Energy Technology Data Exchange (ETDEWEB)

The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.

1981-05-01

436

Water chemistry and corrosion in water-steam circuits of nuclear power plants  

International Nuclear Information System (INIS)

The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.

437

Theoretical studies of Cerro Prieto brines chemical equilibria  

Energy Technology Data Exchange (ETDEWEB)

A chemical equilibrium model is used, implemented in a compact FORTRAN package called HITEQ, to investigate possible mineral deposition related to prereinjection treatment of Cerro Prieto brines for silica removal. Large saturation ratios of the treated brines with respect to several minerals are indicated by these computations. As a remedy, an inexpensive CO/sub 2/ removal scheme aimed at inhibiting carbonate mineral precipitation is proposed. This scheme is quantitatively discussed with the aid of HITEQ. It is concluded that the proposed treatment is both technically and economically feasible.

1980-02-01

438

The chemical properties of silica particle surface in relation to silica-cell interactions  

Energy Technology Data Exchange (ETDEWEB)

Although silicosis has been studied extensively, the mechanism is still not fully understood. Experiments do provide evidence that the actions of unique properties of silica surface on the cell membrane are the starting point of silicotic processes. This paper summarizes literature on chemical properties of silica surface, and the effect of particle size on silica toxicity. This paper also discusses the ways in which silica dusts are though to interact with the cell membrane, with emphasis on freshness, hydrogen bonding, and free-radical interactions.

1989-01-01

439

Request for interim approval to operate 218-E-12B Trench 94 as a chemical waste landfill for disposal of polychlorinated biphenyl wastes in submarine reactor compartments. Revision 1.  

Science.gov (United States)

This request is submitted to seek interim approval to operate a chemical waste landfill for the disposal of polychlorinated biphenyl (PCB) waste. Interim approval is requested for a period not to exceed 5 years. This request covers only the disposal of sm...

1992-01-01

440

Request for interim approval to operate 218-E-12B Trench 94 as a chemical waste landfill for disposal of polychlorinated biphenyl wastes in submarine reactor compartments.  

Science.gov (United States)

This request is submitted to seek interim approval to operate a chemical waste landfill for the disposal of polychlorinated biphenyl (PCB) wastes. This request covers only the disposal of small quantities of solid PCB wastes contained in decommissioned su...

1990-01-01

441

Report of National Cancer Institute symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. I. Common molecular mechanisms  

Science.gov (United States)

Some aspects of molecular mechanisms common to radiation and chemical carcinogenesis are discussed, particularly the DNA damage done by these agents. Emphasis is placed on epidemiological considerations and on dose-response models used in risk assessment to extrapolate from experimental data obtained at high doses to the effects from long-term, low-level exposures. 3 references, 6 figures. (ACR)

1984-01-01

442

Renewable resources - prospects for the chemicals industry  

International Nuclear Information System (INIS)

Improved boundary conditions for the cultivation and utilization of renewable feedstocks in Europe as well as advances in the manufacture and use of intermediate products, special and fine chemicals, and new materials on this basis were the topics of a second symposium, organized this time by Hoechst AG, together with the federal ministry of food, agriculture and forestry, in Frankfurt-Hoechst on May 5th and 6th. With more than 300 attendants from the sectors politics, farming, industry, science and administration, the meeting again encountered great interest. (orig.).

443

Quantitative spectroscopy of close binary stars  

CERN Document Server

The method of spectral disentangling has now created the opportunity for studying the chemical composition in previously inaccessible components of binary and multiple stars. This in turn makes it possible to trace their chemical evolution, a vital aspect in understanding the evolution of stellar systems. We review different ways to reconstruct individual spectra from eclipsing and non-eclipsing systems, and then concentrate on some recent applications to detached binaries with high-mass and intermediate-mass stars, and Algol-type mass-transfer systems.

2011-01-01

444

Pulsed plasma processing of effluent pollutants and toxic chemicals  

International Nuclear Information System (INIS)

The author is exploring the efficiency of pulsed plasma processing in the removal of nitrogen dioxide, nitrogen oxide, and other pollutants. This process uses an electrical discharge to create chemical radicals from air molecules. These radicals can react with pollutants and form harmless compounds. Additives such as hydrocarbons are also used to improve the efficiency of the removal. The efficient removal of nitrogen dioxide has required the presence of dilute aqueous solution of ammonia.

1994-05-01

445

Progress report, December 1, 1979-November 30, 1980. [Chemical poisoning of heterogeneously catalyzed reactions on transition metal surfaces  

Energy Technology Data Exchange (ETDEWEB)

The mechanism of chemical poisoning of model heterogeneously catalyzed reactions on transition metal surfaces is studied. Clean Mo(001) surfaces were characterized; results suggest a first-layer contraction of 10% of the bulk interlayer spacing. Characterization of clean Co(0001) surfaces is underway. Decomposition of formic acid on Mo(001) surfaces is being studied. (DLC)

1980-01-01

446

Poster 20. Analysis of chemical environment conditions in boiling zones  

International Nuclear Information System (INIS)

Boiling phenomenon is responsible for impurities concentration in the liquid phase and then can involve chemically aggressive conditions. This paper presents the methodology developed by NOVATOME to know the water quality conditions in the boiling zone and under deposits, in order to improve corrosion tests and materials reliability and safety. Calculations show that concentration of chloride and sodium hydroxide for example can reach significant levels which may lead to corrosion risks. (author).

447

Physical mechanisms of biological molecular motors  

Energy Technology Data Exchange (ETDEWEB)

Biological motors generally fall into two categories: (1) those that convert chemical into mechanical energy via hydrolysis of a nucleoside triphosphate, usually adenosine triphosphate, regarded as life's chemical currency of energy and (2) membrane bound motors driven directly by an ion gradient and/or membrane potential. Here we argue that electrostatic interactions play a vital role for both types of motors and, therefore, the tools of physics can greatly contribute to understanding biological motors.

2009-03-01

448

PWR steam generator chemical cleaning process  

International Nuclear Information System (INIS)

Some of the origins of corrosion encountered in the secondary side of pressurized water reactor steam generators are:-sludge accumulation (a mixture of metal oxides, primarily magnetite and copper) on tube sheet and attack of tube support plates by aggressive impurities leading to denting. Although Electricite de France has not suffered from these problems, it has developed a chemical cleaning process to dissolve corrosion products at both locations. (author).

1986-10-13

449

Method and apparatus for detecting explosives  

Energy Technology Data Exchange (ETDEWEB)

A method and apparatus is provided for detecting explosives by thermal imaging. The explosive material is subjected to a high energy wave which can be either a sound wave or an electromagnetic wave which will initiate a chemical reaction in the explosive material which chemical reaction will produce heat. The heat is then sensed by a thermal imaging device which will provide a signal to a computing device which will alert a user of the apparatus to the possibility of an explosive device being present.

2011-05-10

450

Methanol -a perspective raw material for the chemical industry  

Energy Technology Data Exchange (ETDEWEB)

Several new development trends in the processing of methanol to various chemical products are discussed. The production of acetic acid by carbonylation of methanol will increase. In the future, methanol is expected to represent the raw material in the production of lower alkenes. The synthesis of lower alcohols, of synthetic gas (homologation), and of aromatic hydrocarbons from methanol are in the research stage.

1983-08-01

451

Measurement of the electrical resistivity of the lithium isotopes at low temperatures  

Energy Technology Data Exchange (ETDEWEB)

The electrical resistivity at low temperatures (T = 10 to 90 K) of the lithium isotopes /sup 6/Li and /sup 7/Li and of an isotopic mixture /sup 7 +6/Li has been studied. The specimens contained a small amount of chemical impurities. An appreciable difference was observed in the temperature dependence of the resistivity produced both by deformation of the phonon spectrum, related to the change in isotopic composition, and by the presence of chemical impurities making the nonequilibrium part of the electron distribution function more isotropic.

1982-03-01

452

MOS device chemical response reversal with temperature  

British Library Electronic Table of Contents (United Kingdom)

Biased above threshold (VT), pulsed photocurrent (u) measurements on windowed silicon Pd gate MOS capacitors are shifted (DV) negatively by H2/N2, whereas Au gates shift positively under NO2/air. Below VT, the shifts are reversed by adjustments of interface state population. Minor temperature increases may coax the device from inversion to depletion, inducing sign reversal of the chemical response.

2010-01-01

453

Green chemistry at work  

Energy Technology Data Exchange (ETDEWEB)

The 1.7 billion pounds of benzene produced each year in the US provide one measure of its utility. At the same time, there are a number of environmental reasons for avoiding the use of benzene in chemical manufacture. Perhaps most compelling: benzene is a potent carcinogen. Scrutiny of many of the chemicals derived from benzene reveals that each molecule contains at least one oxygen atom while benzene completely lacks oxygen atoms. Introduction of oxygen to make up for this lack can require processes that are environmentally problematic. One of the steps used to introduce oxygen atoms during manufacture of adipic acid, a component of Nylon 66, is responsible for 10% of the annual global increase in atmospheric nitrous oxide. This by-product is a causative agent of atmospheric ozone depletion and has been implicated in global warming. With support from EPA and the National Science Foundation, alternative manufacturing processes are being ...

1994-12-31

454

Fouling Study of Silicon Oxide Pores Exposed to Tap Water  

Energy Technology Data Exchange (ETDEWEB)

We report on the fouling of Focused Ion Beam (FIB)-fabricated silicon oxide nanopores after exposure to tap water for two weeks. Pore clogging was monitored by Scanning Electron Microscopy (SEM) on both bare silicon oxide and chemically functionalized nanopores. While fouling occurred on hydrophilic silicon oxide pore walls, the hydrophobic nature of alkane chains prevented clogging on the chemically functionalized pore walls. These results have implications for nanopore sensing platform design.

2007-07-12

455

Extended range chemical sensing apparatus  

Energy Technology Data Exchange (ETDEWEB)

An apparatus for sensing chemicals over extended range of concentrations. In particular, first and second sensors each having separate, but overlapping ranges for sensing concentrations of hydrogen are provided. Preferably, the first sensor is a MOS solid state device wherein the metal electrode or gate is a nickel alloy. The second sensor is a chemiresistor comprising a nickel alloy.

1994-01-01

456

Enhanced Degradation of an Endocrine-Disrupting Chemical, Butyl Benzyl Phthalate, by Fusarium oxysporum f. sp. pisi Cutinase  

UK PubMed Central (United Kingdom)

Compared to yeast esterase, fungal cutinase degraded butyl benzyl phthalate (BBP) far more efficiently; i.e., almost 60% of the BBP disappeared within 7.5 h. Also, the final chemical composition significantly...Full Text Available

2002-09-01

457

Effectiveness of information provision in reducing risks to the environment  

Environmental Research Database

DescriptionAs part of a wider effort to develop new approaches to evaluating and quantifying the benefits of chemicals regulation, this project will review the effectiveness of existing information provision tools (such as classification and labelling for hazardous properties) in terms of affecting user behaviour. As some EC legislation relating to regulation of chemicals has been in place for some time, an assumption is made that the information provided by it is leading to an improvement in the way chem [continued...

2005-01-30

458

Effect of calcination and physico-chemical properties of red mud  

Energy Technology Data Exchange (ETDEWEB)

Physico-chemical studies were carried out on a sample of red mud collected from NALCO, Orissa, after calcination up to 1,200 C at an interval of 100 C. The observed change in properties like surface area, particle size, bulk density and mineral phases etc., can be profitably used while finding an appropriate application of this polluting waste from alumina plants.

1996-10-01

459

Design of solar receivers for chemical energy storage and pyroheliometallurgy applications  

Energy Technology Data Exchange (ETDEWEB)

A preliminary study of two different kinds of solar receivers (a rotating cavity receiver and a volumetric receiver) suitable to operate in the 1 kW solar facility at the University of Rome is presented. Possible applications of solar energy in the aluminum extraction from leucite and chemical storage by the CuO/Cu[sub 2]O cycle are presented and discussed. (author).

1992-01-01

460

DEFINITIVE SOX CONTROL PROCESS EVALUATIONS: AQUEOUS CARBONATE AND WELLMAN-LORD (ACID, ALLIED CHEMICAL, AND RESOX) FGD (FLUE GAS DESULFURIZATION) TECHNOLOGIES  

Science.gov (United States)

The report gives results of economic evaluations of two processes: the Rockwell International aqueous carbonate process (ACP) and the Wellman-Lord process, the latter applied to a sulfuric acid plant, the Foster Wheeler Resox process, and the Allied Chemical coal reduction proces...

461

Comparison of the genetic effects of equimolar doses of ENU and MNU: While the chemicals differ dramatically in their mutagenicity in stem-cell spermatogonia, both elicit very high mutation rates in differentiating spermatogonia  

UK PubMed Central (United Kingdom)

Mutagenic, reproductive, and toxicity effects of two closely related chemicals, ethylnitrosourea (ENU) and methylnitrosourea (MNU), were compared at equimolar and near-equimolar doses in the...Full Text Available

2007-03-01

462

Combining xenoestrogens at levels below individual no-observed-effect concentrations dramatically enhances steroid hormone action.  

UK PubMed Central (United Kingdom)

The low potency of many man-made estrogenic chemicals, so-called xenoestrogens, has been used to suggest that risks arising from exposure to individual chemicals are negligible. Another argument used...Full Text Available

2002-09-01

463

Coir fibre toxicity: in vivo and in vitro studies.  

Science.gov (United States)

The biological activity of coir fibre, coir ash and their components were investigated in vitro by measuring the haemolytic activity and macrophage cytotoxicity. In vivo studies carried out by injecting guinea pigs intratracheally with coir fibres resulted in resolving granulomas. The observed haemolytic activity and macrophage cytotoxicity was more marked with coir ash compared with coir fibres. Chemical analysis of coir ash revealed the presence of toxic chemical constituents in appreciable amounts. PMID:6283694

1982-03-01

464

Chemical modification of humic acids by the introduction of indole-containing fragments  

British Library Electronic Table of Contents (United Kingdom)

A method for the chemical modification of the initial structure of humic acids by acylation with indole-3-acetic acid chloride was developed to increase the biological activity of preparations based on peat and lignite humic acids. The plant growth stimulating effect and the antibacterial activity of the synthesized humic preparations were studied.

2011-01-01

465

Chemical effects on L_#gamma#_1/L_#beta#_1 x-ray intensity ratio of molybdenum compounds  

International Nuclear Information System (INIS)

Chemical effects on the intensity ratio of LX-ray of molybdenum compounds irradiated by 11-keV electrons and by 3-MeV protons were studied using an x-ray crystal spectrometer. It was found that the intensity ratios of L_#gamma#_1/L_#beta#_1 markedly decrease with the increase of ionicity of molybdenum compounds, except for the case of metallic molybdenum. (author).

1987-06-01

466

Behavior and impact assessment of heavy metals in estuarine and coastal zones  

Energy Technology Data Exchange (ETDEWEB)

Contents include: introduction; river systems; physical processes; chemical processes; estuaries and coastal zone; introduction; physical processes; chemical processes; the role of sediments; introduction; the anoxic layer; major-element chemistry; minor-element chemistry; the oxic-anoxic interface; assessment; introduction; analysis of sediments; modelling.

1987-01-01

467

A method for isolating a water influx into a well  

Energy Technology Data Exchange (ETDEWEB)

The goal of the invention is to increase the effectiveness of the isolation process through increasing the waterproofing of the stratum. The cited goal is achieved by isolating water influx into a well through introduction of a chemical reagent into the stratum. To interact with the stratum, an alloy of titanium and iron is introduced into the stratum as the chemical reagent with subsequent pumping of hydrogen into the stratum at 100 to 200C.

1983-01-01

468

Hydrogen production from fossil fuels with carbon dioxide capture, using chemical-looping technologies  

Energy Technology Data Exchange (ETDEWEB)

Carbon capture and storage have been receiving increasing interest lately, mainly as an option to reduce CO{sub 2} emissions from the power sector. The concept could be adapted for production of H{sub 2} as well, which would provide a carbon free energy carrier that could be used for example as transportation fuel. In this doctoral thesis, the option to use chemical-looping technologies to produce H{sub 2} from fossil fuels with CO{sub 2} capture is explored. In chemical-looping combustion, direct contact between fuel and combustion air is avoided. Instead, a solid oxygen carrier performs the task of bringing oxygen from the air to the fuel. Thus, the resulting CO{sub 2} and H{sub 2}O are not diluted with N{sub 2}, and pure CO{sub 2} can easily be recovered by cooling and condensation. The heat of reaction is the same as for ordinary combustion. Chemical-looping reforming uses the same basic principles as ...

2008-04-15

469

Toxicological benchmarks for screening contaminants of potential concern for effects on freshwater biota  

International Nuclear Information System (INIS)

An important early step in the assessment of ecological risks at contaminated sites is the screening of chemicals detected on the site to identify those that constitute a potential risk. Part of this screening process is the comparison of measured ambient concentrations to concentrations that are believed to be nonhazardous, termed benchmarks. This article discusses 13 methods by which benchmarks may be derived for aquatic biota and presents benchmarks for 105 chemicals. It then compares them with respect to their sensitivity, availability, magnitude relative to background concentrations, and conceptual bases. This compilation is limited to chemicals that have been detected on the US Department of Energy's Oak Ridge Reservation (ORR) and to benchmarks derived from studies of toxic effects on freshwater organisms. The list of chemicals includes 45 metals and 56 industrial organic ...

470

Role of accelerator mass spectrometry in biological dosimetry  

International Nuclear Information System (INIS)

Understanding risks from exposures to carcinogens and other chemicals depends upon measurement of their dose to target tissues and their reactivity with critical macromolecules. The authors have used AMS detection of radio-isotopes to assess doses and reactivities at low, environmentally relevant doses. Several biomedical investigations show the effectiveness of quantification of biologically important events at extremely high sensitivity with AMS. Specifically, they have measured the addition of environmental carcinogens such as 2-amino-3,8-dimethylimidazo[4,5-f]-quinoaxaline (MelQx), a chemical found in cooked food, to DNA at concentrations relevant to human exposure. Other low level detection problems in biology, such as immunoassay assessment of small environmental chemicals, is being developed with attomole sensitivity. AMS also aids the assessment of genotoxic risks from chemicals by quantifying ...

1992-04-05

471

Occupational health priorities for health standards: the current NIOSH approach.  

Science.gov (United States)

Government agencies responsible for protecting the public from the adverse effects of toxic chemicals must set priorities for research, regulatory action, protocol testing, and monitoring due to the vast number of toxic chemicals and the limited resources available to these agencies. The National Institute for Occupational Safety and Health (NIOSH) must set priorities for research on hazards encountered in the workplace. Priorities are also utilized by NIOSH in preparing criteria for recommended occupational standards which are forwarded to the Occupational Safety and Health Administration (OSHA), U.S. Department of Labor, for possible promulgation. For various reasons, including rapidly changing conditions in the American workplace, NIOSH has instituted a revised priorities program. In the future, NIOSH research and recommended standards activities will focus not only on individual chemicals, but also on industries, ...

1979-05-01

472

Nitrosamines and rubber  

Energy Technology Data Exchange (ETDEWEB)

Occupational exposure to N-nitrosamines in the rubber industry was first reported by Fajen et al. (1979). In order to study the origin and formation of nitrosamines in this industry, chemicals and industrial products, as well as the air in various working areas, were analysed. All chemicals used for rubber compounding contain nitrosamines if they are derivatives of secondary amines; e.g., tetramethylthiurame, zinc-diethyldithiocarbamate or N-oxydiethylene benzothiazolylsulfenamide. All rubber products containing these dialkyl amine derivatives exhibited considerable levels of the corresponding nitrosamines. Accordingly, variable concentrations of airborne nitrosamines could be detected at places where rubber products are manufactured or stored. The nitrosamines found correspond to the compounded chemicals. The original nitrosamine level in rubber chemicals is not high enough to explain the amounts found ...

1982-01-01

473

Modeling key cupola reactions: Behavior of carbon, silicon and manganese  

Energy Technology Data Exchange (ETDEWEB)

In the present study, models of key chemical processes governing the compositions of the tapped metal from the cupola on the basis of physico-chemical fundamentals have been developed. As evident from the literature survey, the investigations conducted in the past have focused their attention on one phenomenon at a time; for example, a particular chemical reaction, measurement of gas composition or the temperature distribution inside a cupola. Notwithstanding the importance of these studies and their contribution toward the understanding of cupola operation, mathematical models of key chemical processes and their interdependence must be investigated to obtain a complete insight into the various interlinked phenomena occurring inside a cupola. For example, the oxidation of the metallic charge leads to the formation of iron oxide which influences the final content of elements such as silicon, manganese ...

1991-01-01

474

Magnetic and chemical changes in marine sediments  

Energy Technology Data Exchange (ETDEWEB)

A considerable amount of chemical knowledge of marine sediments has been acquired in recent years but has not yet been utilized by paleomagnetists. On the other hand, geochemists are often unaware of the usefulness of numerous magnetic techniques. In this review we try to bridge this gap, and in particular, we outline many of the chemical and magnetic principles that should allow paleomagnetists to better identify and undertand chemical changes that affect the magnetic properties of marine sediments. The chemical principles include those for distinguishing the four major sources of sediments (continental, biological, authigenic/hydrogenous, volcanic/hydrothermal) from one another by determining elemental abundance distributions, as well as for investigating the stabilities of mineral phases relative to changes in pE and pH. The magnetic principles include the effects of authigenesis and diagenesis on ...

1980-05-01

475

Can we do it?  

International Nuclear Information System (INIS)

One wonders how a facility will cope with the new Clean Air Act Amendments (CAAA). Environmental engineers working in large companies' facilities and in corporate engineering groups already have an idea of how to comply with the regulations for chemical plant equipment leaks. (In fact, the rules will also affect process bins, wastewater, transfer and storage.) But those who work for smaller companies or who have assignments not directly tied to environmental affairs may not have access to the latest thinking on compliance. One of the first challenges in becoming aware of the CAAA regulations is learning the new language, which consists of acronyms, some containing other acronyms. NESHAP, for example, stands for national emissions standards for hazardous air pollutants. Prior to the CAAA, NESHAPs applied to a few specific chemicals, such as benzene. Now the proposed rules establish a HON, a hazardous organic NESHAP. According to David Gustafson, ...

476

Biological effects of low level exposures to chemicals and radiation  

International Nuclear Information System (INIS)

In May 1990 a group of scientists representing several federal agencies, the International Society of Regulatory Toxicology and Pharmacology, the private sector, and academia met to develop a strategy to encourage the study of the biological effects of low level exposures (BELLE) to chemical agents and radioactivity. A workshop was held in 1991 with seven invited speakers focusing on the toxicological implications of biological adaptations. The selection of topics and speakers was designed to consider critically the concept of hormesis, not only in a broad, conceptual manner, but also at the molecular and biochemical levels. These presentations offered a complementary perspective on the diverse range of molecular mechanisms that can become activated at low levels of toxicant exposure. In addition to chemical toxicology research, an overview of current research on 'Effects of low-dose radiation on the immune response' was presented as well as ...

477

Applicability of chemical cleaning process to steam generator secondary side, (4). Comprehensive applicability evaluation of chemical cleaning and its effect on integrity of other structural materials other than steam generator tubes  

International Nuclear Information System (INIS)

The application of chemical cleaning for dissolving and removing scale and sludge is being planned in the Japanese pressurized water reactor (PWR) plant in order to maintain high heat transfer performance and to prevent steam generator (SG) tube degradation. In this paper, the effectiveness of the Electric Power Research Institute (EPRI) and German Kraftwerk Union (KWU) processes on the integrity of structural materials other than SG tubes and the comprehensive applicability of chemical cleaning are discussed. The integrity of structural materials such as carbon steel, low-alloy steel and stainless steel was maintained after the EPRI and KWU processes. KWU chemical cleaning tailored for crevice cleaning has been studied to improve its cleaning effectiveness in crevices and to control the corrosion depth of structural materials less than the criterion for corrosion depth. (author)

2006-11-01

478

Quantitative genetic activity graphical profiles for use in chemical evaluation  

International Nuclear Information System (INIS)

A graphic approach, terms a Genetic Activity Profile (GAP), was developed to display a matrix of data on the genetic and related effects of selected chemical agents. The profiles provide a visual overview of the quantitative (doses) and qualitative (test results) data for each chemical. Either the lowest effective dose or highest ineffective dose is recorded for each agent and bioassay. Up to 200 different test systems are represented across the GAP. Bioassay systems are organized according to the phylogeny of the test organisms and the end points of genetic activity. The methodology for producing and evaluating genetic activity profile was developed in collaboration with the International Agency for Research on Cancer (IARC). Data on individual chemicals were compiles by IARC and by the US Environmental Protection Agency (EPA). Data are available on 343 compounds selected from volumes 1-53 of the IARC Monographs and on 115 ...

1990-06-27

479

Coupled modeling of non-isothermal multiphase flow, solutetransport and reactive chemistry in porous and fractured media: 1. ModelDevelopment and Validation  

Energy Technology Data Exchange (ETDEWEB)

Coupled modeling of subsurface multiphase fluid and heat flow, solute transport and chemical reactions can be used for the assessment of acid mine drainage remediation, mineral deposition, waste disposal sites, hydrothermal convection, contaminant transport, and groundwater quality. Here they present a numerical simulation model, TOUGHREACT, which considers non-isothermal multi-component chemical transport in both liquid and gas phases. A wide range of subsurface thermo-physical-chemical processes is considered. The model can be applied to one-, two- or three-dimensional porous and fractured media with physical and chemical heterogeneity. The model can accommodate any number of chemical species present in liquid, gas and solid phases. A variety of equilibrium chemical reactions is considered, such as aqueous complexation, gas dissolution/exsolution, cation ...

1998-09-01

480

Technology assessment: Chlorine chemistry  

International Nuclear Information System (INIS)

Chlorine is not just one of many chemical feedstocks which is used in a few definitely harmful products like PVC or CFC but is irrelevant in all other respects. Just the opposite is true: There is hardly any product line of the chemical industry that can do without chlorine, from herbicides and pesticides to dyes, plastics, pharmaceuticals, photographic atricles, and cosmetics. Chlorine is not only a key element of chemical production but also an ubiquitous element of everyday life in civilisation. There are even many who would agree that the volume of chlorine production is an indicator of the competitive strength and national wealth of a modern society. By now, however, it has become evident that the unreflected use of chlorine is no longer ecologically acceptable. The consequences of a chlorine phase-out as compared to the continued chlorine production at the present level were investigated scientifically by a PROGNOS ...

481

TREATMENT OF RADIOACTIVE EFFLUENTS AT THE MOL LABORATORIES  

Science.gov (United States)

The cold effluents (sanitary waste and decontaminated radioactive water) are flocculated with sodium phosphate and pumped through a trickling filter. The average decontamination obtained is about 86% for alpha emittera and 76% for beta emitters. The cool effluents (activity < 10/sup -3/ mu c/ml) can be treated by several methods. Provisions have been made for two successive chemical flocculations eventually followed by an adsorptlon. The warm waste treatment (activity between 10/sup -3/ and 1 mu c/ml) is still in the experimental stage. The following methods are used: evaporation for some chemically contaminated wastes, browncoal filtration for reactor effluents, and a combination of chemical treatment and browncoal adsorption in other cases. (auth)

1959-10-31

482

Simple chemical method for nanoporous network of In2S3 platelets for buffer layer in CIS solar cells  

British Library Electronic Table of Contents (United Kingdom)

Indium sulfide thin films consisting of porous network of nanoplatelets, have been deposited using chemical bath deposition (CBD) method onto the tin-doped indium oxide (ITO) coated glass substrate. Aqueous solutions of indium sulfate and thioacetamide have been used as indium and sulfur precursors. As a complexing agent, acetic acid was used. The chemically deposited indium sulfide thin films were examined for their structural, surface morphological and optical characterizations. The X-ray diffraction analysis revealed the formation of the cubic b-In2S3 onto the substrate. From scanning electron micrograph, it is observed that the surface of substrate is covered by nanoporous platelets type morphology. The optical studies showed a direct band gap of 2.84eV for indium sulfide platelets. Ph...

2008-01-01

483

Shifts in soil organic matter composition following treatment with sodium hypochlorite and hydrofluoric acid  

British Library Electronic Table of Contents (United Kingdom)

A renewed interest in chemical fractionation of soil organic matter (SOM) originates from the premise that it enables to isolate labile SOM from SOM protected through mineral binding and recalcitrant SOM. Both selective removal of labile non-bound SOM through oxidation or hydrolysis as well as selective removal of minerals and attached SOM are often applied. Molecular-level SOM characterization by means of temperature resolved Pyrolysis-Field Ionization Mass Spectroscopy analysis (Py-FIMS) was used here as an approach to obtain insight into the fate of SOM upon wet chemical treatment with regard to composition and thermal stability. The applied sequential chemical treatment with 6% NaOCl and 10% HF yielded similar sizes in stable SOM fractions between sandy semi-native heathland and cultiv...

2009-01-01

484

PIXE analysis of chinese chicken-blood stone  

Energy Technology Data Exchange (ETDEWEB)

This paper reports the chemical compositions of chicken-blood stone Ji Xue Shi measured by Proton Induced X-ray Emission (PIXE). The experimental result show that for the red portion of chicken-blood stone, the concentration of Hg is as high as 20 wt%, and the concentration of S can be above 10 wt%. For the non-red portion the main chemical compositions are Al{sub 2}O{sub 3} and SiO{sub 2}. The obtained chemical compositions are close to those of kaolinite for Balin chicken-blood stone, and of pyrophyllite for Changhua chicken-blood stone, respectively. So far many Changhua chicken-blood stones and Balin chicken-blood stones were found in China, the PIXE method can be used to explore the provenance of available chicken-blood stones. (author)

1999-07-01

485

On the curvature in logarithmic plots of rate coefficients for chemical reactions  

Science.gov (United States)

In terms of the reduced potential energy barrier ? = ?uTS/kT, the rate coefficients for chemical reactions are usually expressed as proportional to e-?. The coupling between vibrational modes of the medium to the reaction coordinate leads to a proportionality of the regularized gamma function of Euler Q(a,?) = ?(a,?)/?(a), with a being the number of modes coupled to the reaction coordinate. In this work, the experimental rate coefficients at various temperatures for several chemical reactions were fitted to the theoretical expression in terms of Q(a,?) to determine the extent of its validity and generality. The new expression affords lower deviations from the experimental points in 29 cases out of 38 and it accounts for the curvature in the logarithmic plots of rate coefficients versus inverse temperature. In the absence of tunneling, conventional theories predict the curvature of these plots to be identically zero.

2011-05-06

486

Immobilization of bacteria in microgel grafted onto macroporous polyethylene  

Energy Technology Data Exchange (ETDEWEB)

The development of 'Green Chemistry' requires new materials to replace the conventional organic chemistry by biological catalysts, to produce fine chemicals in an environmentally friendly manner. Microbial whole cells can be directly used as biocatalysts, providing a simple and cheap methodology since enzyme isolation and purification are avoided. High-density polyethylene (HDPE) is a very stable polymer though it can be activated by gamma radiation to induce grafting. Glycidyl methacrylate was grafted onto macroporous HDPE and PP in the range of 1-6%, proportional to the initial monomer concentration. Grafted polymers were further chemically modified with ethylenediamine to generate a cationic hydrogel of micron-size thickness onto the internal polymer surfaces. Modified polymers were able to immobilize Gram-positive and Gram-negative bacteria that can catalyze a chemical reaction as efficient as free ...

2010-03-15

487

How to detect acidification in flowing bodies of water? Chemical and zoo-ecological indication along an acidification gradient in two brooks in the western Harz mountains  

International Nuclear Information System (INIS)

The population of the hyporheic interstice and moss cushions by meso- and macroinvertebrates as found at the three measuring points along the Alte Riefensbeek and the Grosse Soese, respectively, in the period from March 1987 to May 1988 is studied and evaluated together with chemical measurements performed between 1987 and 1990. The six measuring points are positioned along an acidification gradient ranging from non-acid to severely acidified. Chemical and biological paramerters are studied with regard to their suitability as indicators of acidification. A model is presented which decribes the influence of abiotic anthropogenic and natural factors on invertebrate species diversity and populations and which can serve as a basis for the calculation of critical deposition burdens. (orig.).

1991-09-24

488

Environmental assessment of proposed effluent limitations guidelines and standards for the transportation equipment cleaning category: Volume 1. Final report  

Science.gov (United States)

This environmental assessment quantifies the water quality-related benefits for Transportation Equipment Cleaning (TEC) facilities based on site-specific analyses of current conditions and the conditions that would be achieved by process changes under proposed BAT (Best Available Technology) and PSES (Pretreatment Standards for Existing Sources) controls. The US Environmental Protection Agency (EPA) estimated instream pollutant concentrations for 157 priority and nonconventional pollutants from three subcategories (barge-chemical and petroleum, rail-chemical, and truck-chemical) of direct and indirect discharges using stream dilution modeling. The potential impacts and benefits to aquatic life are projected by comparing the modeled instream pollutant concentrations to published EPA aquatic life criteria guidance or to toxic effect levels.

1998-05-01

489

Development and validation of a CATHENA fuel channel model for a post-blowdown analysis of the high temperature thermal-chemical experiment CS28-1  

British Library Electronic Table of Contents (United Kingdom)

To form a licensing basis for a new methodology for a fuel channel safety analysis code for CANDU-6 nuclear reactor, a CATHENA model for a post-blowdown fuel channel analysis has been developed, and tested for a high temperature thermal-chemical experiment CS28-1 [Lei, Q.M., 1993. Post-test analysis of the 28-element high-temperature thermal-chemical experiment CS28-1. In: 4th International Conference on Simulation Methods in Nuclear Engineering, Montreal, PQ, 1993]. Pursuant to the objective of this investigation, the current study has focused on understanding the involved phenomena, their interrelations, and how to maintain a good accuracy of the temperature and H2 generation rate prediction without losing the important physics of the involved phenomena. The transient simulation results ...

2009-01-01

490

Decontamination of a gas-cooler by means of chemical reagent loaded foams  

Energy Technology Data Exchange (ETDEWEB)

This paper briefly describes an industrial application of the foam decontamination process applied to large volume components. The process is based on the filling of the component with liquid foam containing suitable chemical reagents, and a circulation loop enables its continuous recycling. The process was successfully validated during the decontamination of a graphite gas-cooler representing a developed area of 1000 m{sup 2}. A decontamination factor up to 190 was obtained leading to a residual activity below 1 Bq/cm{sup 2}. The process only produced 6 m{sup 3} of effluent i.e. about ten times less than for a chemical solution technique. (authors) 2 refs.

1995-12-31

491

Chemical state analysis of Si-base ceramics sliding materials by EPMA  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the present study is to develop a new method for chemical state analysis by means of EPMA(Electron probe microanalyser). The measured X-ray intensity of Si-K{beta} characteristic X-ray spectra were read-out by a 16 bit microcomputer with a RS-232C interface. And using the curve fitting method the quantitative analysis of chemical compositions in a ternary compound that constituted of the same element has been established. The present method was applied to analyse of the friction and wear properties of Si-base ceramics sliding materials. It was found that the wear debris contains both the compositions of the sliding materials and SiO{sub 2}, and the SiO{sub 2} contents in wear debris was changed with relative humidity. The results clearly showed that the proposed method is very useful for determing the compositions in the ternary compound. (author).

1994-03-01

492

Chemical state analysis of Si-base ceramics sliding materials by EPMA  

International Nuclear Information System (INIS)

The purpose of the present study is to develop a new method for chemical state analysis by means of EPMA(Electron probe microanalyser). The measured X-ray intensity of Si-K#beta# characteristic X-ray spectra were read-out by a 16 bit microcomputer with a RS-232C interface. And using the curve fitting method the quantitative analysis of chemical compositions in a ternary compound that constituted of the same element has been established. The present method was applied to analyse of the friction and wear properties of Si-base ceramics sliding materials. It was found that the wear debris contains both the compositions of the sliding materials and SiO_2, and the SiO_2 contents in wear debris was changed with relative humidity. The results clearly showed that the proposed method is very useful for determing the compositions in the ternary compound. (author).

493

Chemical kinetic modeling of chlorinated hydrocarbons under stirred-reactor conditions  

Energy Technology Data Exchange (ETDEWEB)

The combustin of chloroethane is modeled as a stirred reactor so that we can study critical emission characteristics of the reactor as a function of residence time. We examine important operating conditions such as pressure, temperature, and equivalence ratio and their influence on destructive efficiency of chloroethane and production of other chlorinated products. The model uses a detailed chemical kinetic mechanism that we have developed previously for C{sub 3} hydrocarbons. We have added to this mechanism the chemical kinetic mechanism for C{sub 2} chlorinated hydrocarbons developed by Senkan and coworkers. Some reactions have been added to Senkan's mechanism and some of the reaction-rate expressions have been updated to reflect recent developments in the literature. In the modeling calculations, sensitivity coefficients are determined to find which reaction-rate constants have the largest effect on destructive efficiency. 25 refs., ...

1990-10-04

494

Chemical Analysis of Solid-State Irradiated Human Insulin  

British Library Electronic Table of Contents (United Kingdom)

Purpose To study the chemical modifications induced upon irradiation of solid human insulin at radiosterilization doses and investigate the influence of the absorbed dose on radiolysis. Materials and Methods Volatile radiolytic products were monitored by gas chromatography coupled with mass spectrometry (GC-MS) and non-volatile products by two different high performance liquid chromatography (HPLC) methods: the formation of higher molecular weight proteins was assessed by size exclusion liquid chromatography whereas assays for related compounds and chemical potency tests were carried out using reverse-phase HPLC-UV. Conformational changes were investigated by measurements of circular dichroism. Results After gamma irradiation at 10?kGy, the recovery of insulin was 96.8%; higher molecular w...

2006-01-01

495

Cellulose and cellulignin from sugarcane bagasse reinforced polypropylene composites: Effect of acetylation on mechanical and thermal properties  

British Library Electronic Table of Contents (United Kingdom)

This current work is concerned with the development of polypropylene composites reinforced with cellulose and cellulignin fibers attained from sugarcane bagasse. Moreover, the fibers were chemically modified by acetylating process and its effects on the fiber/matrix interaction were also evaluated. The chemical modification efficiency was verified by FTIR analysis and the fibers morphological aspects of fibers by SEM. Likewise, the influence of modified fibers content in the composites was studied by mechanical (tensile, shear and flexural tests) and thermal analyses (TGA and DSC). After the chemical modification, the FTIR results showed the appearance of acetyl groups and reduction of OH bonds for all fibers. Together with, SEM characterization showed that the acetylation changed the morp...

2008-01-01

496

Cell-mediated mutagenesis and cell transformation of mammalian cells by chemical carcinogens. [Rats, hamsters  

Science.gov (United States)

We have developed a cell-mediated mutagenesis assay in which cells with the appropriate markers for mutagenesis are co-cultivated with either lethally irradiated rodent embryonic cells that can metabolize carcinogenic hydrocarbons or with primary rat liver cells that can metabolize chemicals carcinogenic to the liver. During co-cultivation, the reactive metabolites of the procarcinogen appear to be transmitted to the mutable cells and induce mutations in them. Assays of this type make it possible to demonstrate a relationship between carcinogenic potency of the chemicals and their ability to induce mutations in mammalian cells. In addition, by simultaneously comparing the frequencies of transformation and mutation induced in normal diploid hamster cells by benzo(a)pyrene (BP) and one of its metabolites, it is possible to estimate the genetic target size for cell transformation in vitro.

1977-01-01

497

Burn-up measurement of irradiated nuclear fuel by means of micro-gamma scanning  

International Nuclear Information System (INIS)

The Cs-137 radioactivity of a neutron-irradiated nuclear fuel sample has been measured by means of a micro-gamma scanning system which is associated with a high purity Ge detector. Subsequently the burn-up has been calculated from the Cs-137 radioactivity data and then compared with the values from the theoretical computation and chemical anaylsis. The burn-up value obtained with the gamma-scanning system seems to be reasonably agreeable with that of the chemical anaylsis provided that the statistical error in the experiments is taken into account. It is revealed that the burn-up data from the theoretical approach is slightly higher than those of micro-gamma scanning and chemical analysis methods. (Author).

498

Association between chemical and genetic variation in Calophyllum inophyllum, a medicinally important tree of the Western Ghats of India  

British Library Electronic Table of Contents (United Kingdom)

The objective of the present work is to study the chemical variation in Calophyllum inophyllum growing along the Western Ghats of India. Contents of dipyranocoumarins (inophyllums) in C.?inophyllum were determined to assess whether they could be used as a taxonomic marker for C.?inophyllum. This study also aims to establish inter simple sequence repeat (ISSR) markers that can be used to study genetic variation within the species and explore correlation between ISSR and chemical markers. The contents of dipyranocoumarins were estimated in seeds collected from 20 locations. Leaves from plants at the same 20 locations were assayed for ISSR variation. A dendrogram based on Nei?s genetic distance as well as principal component analysis based on dipyranocoumarins and ISSR variation clustered pla...

2011-01-01

499

Active hydrogen by chemical ionization mass spectrometry.  

Science.gov (United States)

A means of determination of a ctive hydrogen of hydroxyl, carboxyl, sulfhydryl, amino, amido and sulfonamido groups by chemical ionization mass spectrometry using ammonia and trideuterioammonia as reagent gases is described. The method is based on exchange of active hydrogen for deuterium occurring during the chemical ionization process using trideuterioammonia, with comparison of m/z for ammonium adduct [M + NH1]+ and trideuterioammonium adduct [M--nH + nD + ND4]+, or of protonated molecular ion [M + H]+ and deuteronated molecular ion [M--nH + nD + D]+ yielding the number of active hydrogens. Applications have been made to several classes of biologically important compounds. PMID:427257

1979-01-01

500

A guide to developing and implementing safety checklists: Plant steam utilities  

British Library Electronic Table of Contents (United Kingdom)

Abstract Steam generation is an integral part of most chemical process plants; however, the steam plant often is or can be overlooked in the area of hazard analysis. The reasons for this oversight are obvious: steam generation is considered to be an old and well-understood process, and steam boiler systems are often not considered to pose the same hazards as other plant units. However, modern steam boiler systems are fueled with natural gas, pulverized coal, and/or fuel oil; each of which poses significant fire and explosion hazards. For example, a moderately sized chemical plant's boiler house may have two or three boilers operating at 240 MMBTU/hr, with each using approximately 11 ton/hr of subbituminous pulverized coal feed. Chemical plants rely on equipment design and installation, mai...

2011-01-01