UK PubMed Central (United Kingdom)

Oestrogen has been reported to modulate tumour necrosis factor (TNF), interleukin (IL)-1 and IL-6 cytokine levels in human mononuclear cell cultures. In the present study, the effects of exogenous oestrogen...Full Text Available

Science.gov (United States)

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UK PubMed Central (United Kingdom)

An attempt was made to programme ovulation in women on a predetermined day of the menstrual cycle by treatment used to induce ovulation in anovulatory sterility. At laparotomy for elective sterilization...Full Text Available

KoreaScience (Korea)

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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

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

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

International Nuclear Information System (INIS)

The effects on reproductive functions of feeding adult rhesus monkeys on a diet of irradiated wheat flour and potato was investigated. Wheat flour and potatoes were exposed to 75 000 and 10 000 rad, respectively, of #gamma#-irradiation and then fed to the animals. Various parameters of reproductive function were compared with those of animals fed on unirradiated food. These were: external changes in the reproductive organs, menstrual cycle, vaginal cytology, assay of urinary hormones (oestrogens and pregnanediol), and post-mortem histopathological examination of the reproductive organs. At the end of 3 months, the experimental and control animals behaved similarly with regard to their reproductive functions. (author).

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

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

UK PubMed Central (United Kingdom)

BackgroundThe aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates the toxicity and biological activity of dioxins and related chemicals. The...Full Text Available

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 ...

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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.

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Decontamination and decommission activities related to the Molten Salt Reactor Experiment (MSRE) involve the trapping and recovery of radiolitically generated uranium hexafluoride and fluorine. Although fission product radiolysis was known to generate F{sub 2}, the formation of UF{sub 6} and its transport from the fuel salt was unexpected. Some of these gaseous radiolysis products have been moving through the gas piping to a charcoal bed since the reactor was shut down in 1969. Current and planned remediation and clean-up activities involve the trapping of the gaseous products, deactivation and treatment of the activated charcoal bed, stabilization and reconditioning of the fuel salt, and recovery of the uranium. The chemical aspects of these processes, including radiolytic generation mechanisms, reactions between uranium hexafluoride and fluorine and trapping materials such as ...

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 ...

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, ...

Energy Technology Data Exchange (ETDEWEB)

A compilation of all universities, industrial and governmental agencies in Quebec which are actively involved in research and development of chemical products and industrial materials derived from biomass products, was presented. Each entry presented in a standard format that included a description of the major research activities of the university or agency, the principal technologies used in the research, available research and analytical equipment, a description of the research personnel, names, and addresses of contact persons for the agency or university. Thirty entries were presented. These covered a wide diversity of activities including biotechnological research such as genetic manipulations, bioconversion, fermentation, enzymatic hydrolysis and physico-chemical applications such as bleaching, de-inking, purification and synthesis. tabs.

UK PubMed Central (United Kingdom)

SummaryTRPV1 is the founding and best-studied member of the family of temperature-activated transient receptor potential ion channels (thermoTRPs). Voltage, chemicals, and heat...Full Text Available

UK PubMed Central (United Kingdom)

New approaches to the risk assessment process are needed that might be more definitive and satisfying to the scientific community, interest groups, and the public at large. This commentary examines...Full Text Available

Science.gov (United States)

Environmental surveys to provide base-line data for assessing the potential impact of the operation of Wolseong NPP on marine ecosystems were performed at 3-month intervals in 1981. Physico-chemical properties of seawater and gross beta activities in seaw...

UK PubMed Central (United Kingdom)

Auxin modulates diverse plant developmental pathways through direct transcriptional regulation and cooperative signaling with other plant hormones. Genetic and biochemical approaches have clarified...Full Text Available

UK PubMed Central (United Kingdom)

In Pseudomonas paucimobilis UT26, gamma-hexachlorocyclohexane (gamma-HCH) is converted by two steps of dehydrochlorination to a chemically unstable intermediate, 1,3,4,6-tetrachloro-1,4-cyclohexadiene...Full Text Available

UK PubMed Central (United Kingdom)

Cells have an internal compass that enables them to move along shallow chemical gradients. As amoeboid cells migrate, signaling events such as Ras and PI3K activation occur spontaneously on pseudopodia....Full Text Available

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)

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The size of the market for pulverized activated charcoal and particulate activated charcoal prepared by the Association of Inorganic Chemicals of Japan is 55,000t/y (1987) in total. Individually, some fields showed the expansion such as water purification, water treatment and gas treatment on the one hand, but on the other hand, several fields showed the decline such as sugar refining, dextrin sugar and soda glutamate. As a whole, the market showed no marked fluctuations or a very slight increase. Many of the above usages are traditional in the chemical industry and the food industry, etc., and the new usages developed in the past several years have not grown to influence the statistics as yet. Selection of raw material is the key for determining the character of activated charcoal. And the factors of determining the characteristic features are fine pore, surface area and surface ...

Energy Technology Data Exchange (ETDEWEB)

The bibliography contains citations from a worldwide literature survey pertaining to the uses of activated charcoal in industry as well as in the laboratory, including its use in air pollution, chemical adsorption, radioactive waste adsorption, electrochemistry, industrial waste treatment, and the mining industry. (This updated bibliography contains 92 citations, 12 of which are new entries to the previous edition.)

Energy Technology Data Exchange (ETDEWEB)

Alkanol-amine is used for removing hydrogen sulfide and carbon dioxide from the gas stream. Contaminated amine is the amine which is contaminated by hydrocarbon, organic acid or iron sulfide, etc.. In addition, in the case when an antifoaming agent is excessively added to it or when it is decomposed chemically or thermally, it is considered that it is contaminated. When an amine solution becomes contaminated, several problems concerning operation control occur which would influence the effect of the amine treatment in consequence. By using activated charcoal, it is possible to decrease the additional amount of the antifoaming agent or corrosion inhibitor. This is because activated charcoal removes the decomposed product which causes the foaming phenomenon. In order to derive economical profit sufficiently, an activated charcoal system properly designed is necessary. In this article, the CALGON ...

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 ...

CERN Document Server

A general quantum adiabatic theorem with and without the time-dependent orthogonalization is proven, which can be applied to understand the origin of activation energies in chemical reactions. Further proofs are also developed for the oscillating Schwinger Hamiltonian to establish the relationship between the internal (due to time-dependent eigenfunctions) and external (due to time-dependent Hamiltonian) time scales. We prove that this relationship needs to be taken as an independent quantum adiabatic approximation criterion. We give four examples, including logical expositions based on the spin-1/2 two-level system to address the gapped and gapless (due to energy level crossings) systems, as well as to understand how does this theorem allows one to study dynamical systems such as chemical reactions.

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.

British Library Electronic Table of Contents (United Kingdom)

This paper is dedicated to the treatment of sludge occurring in frame of the Egyptian produced from oil and gas production. The activity levels of three radium isotopes: Ra-226 (of U-series), Ra-228 and Ra-224 (of Th-series) in the solid TENORM waste (sludge) were first evaluated and followed by a sequential treatment for all radium species (fractions) presented in TENORM. The sequential treatment was carried out based on two approaches `A' and `B' using different chemical solutions. The results obtained indicate that the activity levels of all radium isotopes (Ra-226, Ra-228 and Ra-224) of the environmental interest in the TENORM waste sludge were elevated with regard to exemption levels established by IAEA [International Atomic Energy Agency (IAEA), International basic safety standards f...

British Library Electronic Table of Contents (United Kingdom)

Nanoparticle metal oxides offer a wide variety of potential applications in medicine due to the unprecedented advances in nanobiotechnology research. In this work, the effect of zinc oxide (ZnO) nanoparticles prepared by mechano-chemical method on the antibacterial activity of different antibiotics was evaluated using disk diffusion method against Staphylococcus aureus and Escherichia coli. The average size of ZnO nanoparticles was between 20 nm and 45 nm. Although ZnO nanoparticles (500 mg/disk) decreased the antibacterial activity of amoxicillin, penicillin G, and nitrofurantoin in S. aureus, the antibacterial activity of ciprofloxacin increased in the presence of ZnO nanoparticles in both test strains. A total of 27% and 22% increase in inhibition zone areas was observed for ciprofloxac...

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Since the beginning of the large-scale technical manufacture of activated charcoal at the start of the century, this product has become increasingly important. Activated charcoal is a central part today of many chemical industrial processes. Furthermore, the purification of exhaust air and liquid wastes is often based on the adsorption by activated charcoal. The constantly increasing hygienic demands made of our drinking water may also often only be fulfilled by using activated charcoal. The highly developed adsorption technique of today is considerably supported by continuous improved quality of the products which can only be achieved by progress in manufacturing techniques. The large-scale use of activated charcoal has only become possible for a series of tasks by developing suitable reactivation methods. The last German-language monograph on ...

Energy Technology Data Exchange (ETDEWEB)

A procedure for high level tritium labelling at the C2-H position of adenosine 5`-triphosphate ([2-{sup 3}H]-ATP, 1), based on the tritiodehalogenation reaction of 2-bromoadenosine 5`-triphosphate (2) has been elaborated. This precursor was prepared in a six-step synthesis from guanosine. The tritiodehalogenation of (2) for three hours over palladium oxide in phosphate buffer yielded tritium labelled ATP with high specific activity, in good chemical yield. (author).

Energy Technology Data Exchange (ETDEWEB)

Microorganisms are ubiquitous in subsurface environments although their populations sizes and metabolic activities can vary considerably depending on energy and nutrient inputs. As a result of their metabolic activities and the chemical properties of their cell surfaces and the exopolymers they produce, microorganisms can directly or indirectly facilitate the biotransformation of radionuclides, thus altering their solubility and overall fate and transport in the environment. Although biosorption to cell surfaces and exopolymers can be an important factor modifying the solubility of some radionuclides under specific conditions, oxidation state is often considered the single most important factor controlling their speciation and, therefore, environmental behavior.

Energy Technology Data Exchange (ETDEWEB)

This study of the inorganic chemical composition of 10 different Nigerian medicinal plant species, using the technique of instrumental neutron activation analysis (INAA), resulted in the determination of the concentrations of 18 major, minor, and trace elements: Al, Ba, Br, Ca, Cl, Eu, Fe, Ga, K, La, Mn, Na, Sb, Sc, Si, Sm, V, and Zn. The parts of the plants used were roots, leaves, and bark. The NBS SRM 1571 Orchard Leaves was also analyzed to assess the accuracy of the procedures used. 21 refs., 4 tables.

Energy Technology Data Exchange (ETDEWEB)

Results from four chemical-equilibrium computer programs, REDEQL.EPAK, GEOCHEM, WATEQF, and SENECA2, have been compared with experimental solubility data for some simple systems of interest with geothermal brines. Seven test cases involving solubilities of CaCO/sub 3/, amorphous SiO/sub 2/, CaSO/sub 4/, and BaSO/sub 4/ at various temperatures from 25 to 300/sup 0/C and in NaCl or HCl solutions of 0 to 4 molal have been examined. Significant differences between calculated results and experimental data occurred in some cases. These differences were traced to inaccuracies in free-energy or equilibrium-constant data and in activity coefficients used by the programs. Although currently available chemical-equilibrium programs can give reasonable results for these calculations, considerable care must be taken in the selection of free-energy data and methods of calculating activity coefficients.

Energy Technology Data Exchange (ETDEWEB)

This report consists of a broad overview of activities at Los Alamos National Laboratory (LANL). The following topics are discussed: The growth of the waste management group; what we do today; the mission of the waste management group; the liquid waste treatment section; the radioactive liquid waste project office; the chemical waste section; the radioactive waste section; and the technical support section.

International Nuclear Information System (INIS)

Mechanical properties of vanadium, irradiated with fast neutrons up to 8.6x10"-"4 dpa depending on postirradiation annealing temperature, are studied. It is shown that radiation-annealing hardening (RAH) is observed at 300 deg C, which agrees with earlier performed studies. It is first stated that RAH is accompanied by plasticity decrease. Phenomenological model permitting to explain RAH dependence on irradiation temperature and dose and also on content of chemically active alloying impurities is suggested.

International Nuclear Information System (INIS)

Technological processes of welding are significant sources of pollution in the working area. Evaluation of chemical quality of working area was made by means of radionuclide x-ray fluorescence analysis and activation analysis with fast neutrons. Welding aerosols were sampled by filtration method on Synpor 4 membrane ultra-filters. For selected types of welding filter metals, determination of heavy metals in aerosols was performed. (author).

Energy Technology Data Exchange (ETDEWEB)

This paper describes the application of the instrumental analytical methods: neutron activation techniques, atomic absorption spectroscopy and flame emission spectroscopy, used to analyse some home-made teas, determining Na, K and Cl and comparing the results. This study verify whether the home-made teas used for rehydration of the children reach the composition recommended by WHO (World Health Organization). (author). 6 refs., 6 tabs.

Energy Technology Data Exchange (ETDEWEB)

A series of 2-alkylthiopyrine-4-carbothioamides were synthesized, and their anti-fungal potency was tested. The chemical structures were proved by infrared spectroscopy (IR) and {sup 1}H nuclear magnetic resonance ({sup 1}H-NMR) data and by elemental analysis. The minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) assessment were used for the estimation of potential activity in vitro. The study comprising 21 clinical isolates of fungi showed that two compounds exhibited fair inhibitory activity against some yeasts and dermatophytes. Selective fungistatic activity against non-dermatophytes (MIC = 3.12-25.0 {mu}g/mL) was found also in another compound. None of the above compounds showed inhibitory activity against non-dermatophyte filamentous fungi. Microbiological activity of 2-alkylthiopyridine-4-carbothioamides appears to be ...

British Library Electronic Table of Contents (United Kingdom)

Mono- and disubstituted novel derivatives of the heptaene nystatin analog 28,29-didehydronystatin A1 (S44HP, 1) were obtained by chemical modification of the exocyclic C-16 carboxyl and/or an amino group of mycosamine moiety. The strategy of preparation of mono- and double-modified polyene macrolides was based on the use of intermediate hydrophobic N-Fmoc (9-fluorenylmethoxycarbonyl) derivatives that facilitated the procedures of isolation and purification of new compounds. The antifungal activity of the new derivatives was first tested in vitro against yeasts and filamentous fungi, allowing the selection of the most active compounds that were subsequently tested for acute toxicity in mice. 2-(N,N-dimethylamino)ethylamide of 1 (2) and 2-(N,N-dimethylamino)ethylamide of N-fructopyranosyl-28...

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Surveillance and maintenance (S & M) of 75 sites were conductd by the Remedial Action Section for the Environmental Restoration Program for surplus facilities and sites contaminated with radioactive materials and/or hazardous chemicals. S & M activities on these sites were conducted from the end of their operating life until final facility disposal or site stabilization. The objectives of the Waste Area Grouping S & M Program are met by maintaining a program of routine S & M as well as by implementing interim corrective maintenance when deemed necessary as a result of site surveillance. This report briefly presents this program`s activities and includes tables indicating tank levels and dry well data for FY 1991.

British Library Electronic Table of Contents (United Kingdom)

The coastal ecosystem health assessment is a field of increasing importance. In this paper, a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made, mainly based on remote sensing data and GIS technique. Its spatial and quantitative evaluation was facilitated by the progress of remote sensing and GIS technique development. Firstly, human activities, hydrology and ecosystem problems in the study area were discussed and analyzed. Secondly, from 4 aspects of human stress, physical, chemical and biological responses to anthropogenic activities and natural stress, several indicators such as water transparency (Secchi Disk Depth, SDD), suspended substance concentration, dissolved inorganic nitrogen, active phosphate, chlorophyll, harmful algae bloom, as well as distr...

British Library Electronic Table of Contents (United Kingdom)

Dopant-free Bi2Ti2O7 thin films with pyrochlore structure and La-doped bismuth titanate thin films have been fabricated by means of chemical solution decomposition, and characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy and UV?Vis spectrophotometry in this study. Their photocatalytic activities have been evaluated by photodegrading methyl orange solution, and the optimum processing parameters for the highest photocatalytic activity have been found. Moreover, the effects of La-doping on the phase transformation and the photocalalytic activity have been studied. It has been deduced from the experiment result that substituted La3+ ions can act as a stabilizer of Aurivillus phase BLT and a grain?growth inhibitor in BLT thin films.

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Cost-time management methods have been developed by Westinghouse to examine business applications from a cost-time perspective. The initial application of cost-time management within Westinghouse was targeted at reducing cycle time in the manufacturing sector. As a result of the tremendous success of reduced cycle time in manufacturing, Westinghouse initiated application of the management technique to Environmental Restoration activities at its Government Owned Contractor Operated facilities. The Westinghouse initiative was proposed in support of the Department of Energy`s goals for cost effective Environmental Restoration activities. This paper describes the application of the cost-time method to Environmental Restoration work currently being performed at the Idaho National Engineering Laboratory (INEL) for the Department of Energy (DOE) by Westinghouse Idaho Nuclear Company (WINCO).

International Nuclear Information System (INIS)

Preliminary observations on the isothermal carbon transfer in low-carbon Alloy-800 exposed in sodium with AISI-304 type of steel at 550_0 are reported. The alloy was found to undergo a carburization comparable or slightly lower than that observed for the AISI-304 stainless steel for carbon activities above 6 x 10 /sup -3/ at 550_0C, but was not found to decarburize below such a carbon activity value. In the examined range the chemical composition of the alloys does not affect the process out of the experimental uncertainty of measure. Conclusions concerning the effective diffusion for carbon in the alloy are formulated. Preliminary relationships were found for an empirical evaluation of the carburization of the Alloy-800 in sodium of known carbon activity.

Science.gov (United States)

Enzymatic reactions in non-aqueous media have been shown to be effective in carrying out chemical transformation where the reactants are insoluble in water or water is a byproduct limiting conversion. Ionic liquids, liquid organic salts with infinitesimal vapor pressure, are potentially useful alternatives to organic solvents. It is known that the thermodynamic water activity is an important variable affecting the activity of enzymes in non-aqueous solvents. This study investigated the influence of water activity on the esterification of geraniol with acetic acid in ionic liquid [bmim]PF6 catalyzed by immobilized Candida antarctica lipase B. The conversion of geraniol in [bmim]PF6 was significant although the reaction rate was slower than in organic solvents. The profile of initial reaction rate-water activity was determined experimentally, and differed from the data reported for ...

International Nuclear Information System (INIS)

Phenolic resins have made a major breakthrough in the field of high technology in 80's. These are now active participants of "high tech' areas ranging from electronics, computers, communication, outer space, aerospace, advanced materials, bio materials and technology. A phenol - formaldehyde (1:1.5) resin having resin content of 70% synthesized in the laboratory has been applied for wood coating and reinforcing glass fiber. The weatherability and solvent resistance of these items have been studied and results discussed keeping in view the envisaged application for structural materials and chemical equipment. The toxic materials released during contact with solvents for chemical applications and during degradation general have been monitored. The results are discussed with reference to environmental pollution due to these resins and their composites under different conditions. (authors)

International Nuclear Information System (INIS)

The introduction of oxygen in the vicinity of a metallic target surface, bombarded with positive argon ions of twenty kiloelectron-volts, increases the number of sputtered atoms in the excited state. This phenomenon of exaltation, very sensitive in the case of nickel and aluminium, is much less marked in the case of molybdenum. Moreover, the emission of excited particles coming from the beam's ions is not modified. A quantum-mechanical model of a kinetic emission process, which permits the interpretation of the clean metallic target's emission phenomena, seems insufficient to explain all of the results obtained in the presence of oxygen. In this last case one can therfore use a thermodynamic model in which excited metallic particles can be formed directly by chemical surface reactions of neutralization or reduction. (orig.).

Energy Technology Data Exchange (ETDEWEB)

This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical process that affect the progeny's atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. This report describes the progress toward ...

Energy Technology Data Exchange (ETDEWEB)

This report presents research presented at the poster session of the Symposium covering a wide spectrum of current biotechnological research activities. Research focused mostly on ethanol production and methane generation from biomass material via microbial processing, as well as on enhanced hydrogen yield from algae. Several of the posters dealt with the pretreatment of cellulosic materials, and enzyme production/characterization, while a good number of papers displayed research efforts on bioremediation, photosynthesis, production of various useful chemicals from biomass by bioprocessing, and on other miscellaneous subjects. One of the papers treated a very interesting topic of cellulose-cellulase complexes. Many of the poster papers are included in this volume, and a synopsis of all the poster/papers presented is the subject of this article.

Energy Technology Data Exchange (ETDEWEB)

In developing new brain imaging agents for single photon emission computed tomography (SPECT), we synthesized eleven radioiodinated phenoxyacetic acid derivatives and investigated the relationship between the chemical structure and in vivo characteristics. Biodistribution studies in mice revealed high initial brain uptake for all the compounds. Blood radioactivity level depended markedly upon the chemical stability of the compound. The alpha,alpha-dimethylester derivative, amide derivatives and diamine derivatives, which were stable to hydrolysis, showed low blood activity levels following intravenous administration. Disappearance of the ester and amide compounds from the brain was rapid. However, the diamine derivatives displayed improved retention in the brain. Compounds 3a and 4 possessed the best combination of high brain uptake and sufficient retention to be useful as potential brain imaging radiopharmaceuticals with ...

Energy Technology Data Exchange (ETDEWEB)

Odor purification process using bio-function, which is technologically called bio-deodorizing process, utilizes the function of microorganism to convert mal-odor substances to non-odor substances. It attracts attention because the operation cost of a facility is low due to non-use of chemicals and energy, and because it is environmentally friendly without the possibility of generating secondary pollution. It is being used in deodorizing at sewage treatment facilities, fertilizer plants, coating plants, and foundries in Japan, and is more widely used in Europe. The conventional deodorizing technology in Japan mostly focuses on processes of physical chemistry such as activated carbon treatment, chemical scrubbing, combustion, and masking, but bio-deodorizing process tends to replace the conventional processes. This paper explains (1) relation of mal-odor and microorganism, (2) bio-deodorizing system (solid phase system and ...

British Library Electronic Table of Contents (United Kingdom)

Direct electrochemistry and electrocatalysis of catalase (Cat) was studied based on a nano-composite film consisting of amine functionalized graphene and gold nanoparticles (AuNPs) modified glassy carbon electrode. Graphene was synthesized chemically by Hummers and Offeman method and then was functionalized with amino groups via chemical modification of carboxyl groups introduced on the graphene surface. The nano-composite film showed an obvious promotion of the direct electron transfer between Cat and the underlying electrode, which attributed to the synergistic effect of graphene-NH2 and AuNPs. The resultant bioelectrode retained its biocatalytic activity and offered fast and sensitive H2O2 quantification. Under the optimized experimental conditions, hydrogen peroxide was detected in the...

British Library Electronic Table of Contents (United Kingdom)

A model is developed to represent mechanical strain, stress-enhanced dissolution, and shear dilation as innately hysteretic and interlinked processes in rough contacting fractures. The model is incorporated into a numerical simulator designed to examine permeability change and thermal exchange in chemically active and deformable fractured reservoirs. A candidate engineered geothermal reservoir system (EGS) is targeted. The mechanistic model is able to distinguish differences between the evolution of fluid transmission characteristics of (1) small scale, closely spaced fractures, and (2) large-scale, more widely spaced fractures. Alternate realizations of fracture frequency and scale, exhibiting identical initial bulk permeability, lead to significantly different conclusions regarding perme...

British Library Electronic Table of Contents (United Kingdom)

SBA-15 supported nano-scaled copper oxide was synthesized by impregnation method via ultrasonic-assisted route. The removal test from gas mixture containing 0.1?vol.% hydrogen sulfide was carried out over this material at atmospheric conditions. The effects of the chemical nature of copper oxide and the textural properties of the material on removal capacity were studied. The materials before and after the removal test were analyzed by nitrogen adsorption, X-ray diffraction, Transmission Electron Microscope, X-ray photoelectron Spectroscopy, Fourier Transform Infrared Spectrometer and Inductive Coupled Plasma. The results showed that copper species are located predominantly in mesopore channels, existing as copper oxide nanoparticles. Mesopores are active sites for removal reaction. The ou...

International Nuclear Information System (INIS)

The problems are discussed of using radionuclide X-ray fluorescence analysis (the most frequently used source is "2"4"1Am) and neutron activation analysis for monitoring the chemical quality of the working environment of a welder. Elements determinable by these methods are listed and the advantages of the methods stated with regard to speed, simplicity and appropriate accuracy of measurement together with commercial availability of the instruments. Welding as a source of harmful substances is assessed by determination of the amount of chromium in aerosols generated by welding austenitic chromium-nickel steels. The described methods allow to obtain a complex image of the chemical nature of welding aerosols and to understand the mechanism of their impact on the human organism. (J.C.).

Science.gov (United States)

The LLNL Chemical & Biological National Security Program (CBNP) provides science, technology and integrated systems for chemical and biological security. Our approach is to develop and field advanced strategies that dramatically improve the nation's capabilities to prevent, prepare for, detect, and respond to terrorist use of chemical or biological weapons. Recent events show the importance of civilian defense against terrorism. The 1995 nerve gas attack in Tokyo's subway served to catalyze and focus the early LLNL program on civilian counter terrorism. In the same year, LLNL began CBNP using Laboratory-Directed R&D investments and a focus on biodetection. The Nunn-Lugar-Domenici Defense Against Weapons of Mass Destruction Act, passed in 1996, initiated a number of U.S. nonproliferation and counter-terrorism programs including the DOE (now NNSA) Chemical and Biological ...

Energy Technology Data Exchange (ETDEWEB)

Developing markets in the Pacific Basin depend heavily on the production and export of consumer goods. The generation of hazardous waste as a by-product of industrial production can be linked to adverse health outcomes, such as childhood leukemia, in ways that are presently unknown. In California, exposures resulting from hazardous waste disposal are of concern in the etiology of childhood cancer. Approximately 63% of the 57 hazardous waste sites that the U.S. Environmental Protection Agency (USEPA) included in the national priority list under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) statute were in the six-county San Francisco Bay area. This area includes California`s Silicon Valley, where a disproportionate majority of these sites are located. Although only one study links hazardous waste disposal to childhood leukemia evidence is accumulating that in utero and maternal pesticide exposures as well as chemical exposures ...

Energy Technology Data Exchange (ETDEWEB)

the development of lithium metal batteries is hindered by the bad reversibility of the Li{sup +}/Li pair, due to dendrites formation which limits the amount of active matter and can generate short-circuits. The chemical and electrochemical phenomena which take place at the electrode/organic electrolyte interface lead to the formation of a complex passivation film which is of prime importance for the functioning of this type of batteries. The in-situ infrared reflection spectroscopy is well adapted to the chemical study of the passivation layer. Two different techniques were used: the substraction normalized interfacial transform infrared spectroscopy (SNIFTIRS) and the electro-chemically modulated infrared reflectance spectroscopy. These methods have shown that the passivation layer that develops on the surface of the lithium electrode in contact with organic solutions (propylene carbonate, ethylene ...

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This paper deals with an industrial application of the foam decontamination process applied to large volume components. The work presented below was achieved within the context of a CEC contract. The objective of this 4-year programme was to study, develop and demonstrate an effective in-situ decontamination process using foams containing suitable chemical reagents. Laboratory tests were first performed to optimize the chemical formulation of the foams. Pilot tests were then conducted to study the hydrodynamic features of the fluids and to adapt a technique of permanent foam circulation. With these tests completed, it was essential to validate the foam process on an industrial scale and on a representative nuclear component. The objective was successfully achieved. The process was effectively validated during the decontamination of a graphite-gas cooler representing a developed area of 1000 m{sup 2}. Results were quite convincing since the ...

Science.gov (United States)

We report on recent progress and improvements in the metal-organic chemical vapor deposition (MOCVD) growth of mid-infrared lasers and using a high speed rotating disk reactor (RDR). The devices contain AlAsSb active regions. These lasers have multi-stage, type I InAsSb/InAsP quantum well active regions. A semi-metal GaAsSb/InAs layer acts as an internal electron source for the multi-stage injection lasers and AlAsSb is an electron confinement layer. These structures are the first MOCVD multi-stage devices. Growth in an RDR was necessary to avoid the previously observed Al memory effects found in conventional horizontal reactors. A single stage, optically pumped laser yielded improved power (greater than 650 mW/facet) at 80K and 3.8um. A multi-stage 3.8-3.9um laser structure operated up to T=170K. At 80K, peak power greater than 100mW and a high slope- efficiency were observed in gain guided lasers.

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Many assays for oncogenic transformation have been developed ranging from those in established rodent cell lines where morphological alteration is scored, to those in human cells growing in nude mice where tumor invasiveness is scored. In general, systems that are most quantitaive are also the least relevant in terms of human carcinogenesis and human risk estimation. The development of cell culture systems has made it possible to assess at the cellular level the oncogenic potential of a variety of chemical, physical and viral agents. Cell culture systems afford the opportunity to identify factors and conditions that may prevent or enhance cellular transformation by radiation and chemicals. Permissive and protective factors in radiation-induced transformation include thyroid hormone and the tumor promoter TPA that increase the transformation incidence for a given dose of radiation, and retinoids, selenium, vitamin E, and 5-aminobenzamide that ...

Energy Technology Data Exchange (ETDEWEB)

Implementation of Noble Metal Chemical Application (NMCA) in a Boiling Water Reactor (BWR) requires injection of a noble metal compound while the reactor is idle at hot shutdown conditions. In order to minimize outage time, utilities are very pro-actively finding ways to reduce the number of critical path tasks. One of these tasks is to remove some containment vessel drywell head bolts during the NMCA idle time. This, thereby, saves the utilities outage time, or they can perform other tasks as desired. Using design basis conditions and state-of-the-art analytical techniques, detailed finite element stress analyses of the closure region are performed. Two acceptance criteria are evaluated. The first is that contained within Section III of the ASME Code for allowable stresses. The second relates to leak tightness, i.e., with bolt removal the joint must still remain leak tight. This paper describes the activities performed to ...

International Nuclear Information System (INIS)

Constitutive activation of the oncogenic transcription factor STAT3 frequently occurs in various human malignancies. STAT3 activation involves dimerization via intermolecular pTyr-SH2 interaction. Thus, antagonizing this interaction is a feasible approach to inhibit STAT3 activation for cancer therapy. In order to identify selective STAT3 inhibitors, we developed a biochemical HTS system based on AlphaScreen technology, which measures the abilities of test compounds to antagonize pTyr-SH2 interactions. We screened our chemical libraries using this system and identified 5,15-diphenylporphyrin (5,15-DPP) as a selective STAT3-SH2 antagonist. Selective inhibition of STAT3 nuclear translocation and DNA biding activity was observed in cells treated with 5,15-DPP. IL-6-dependent dimerization of STAT3, c-myc promoter binding and c-myc protein expression were all suppressed by 5,15-DPP, ...

Science.gov (United States)

The kainoid amino acids are biologically important compounds because they show remarkable neuroexcitatory and excitotoxic activities. For exhibiting potent activity, the stereochemical relationship of the substituents on the pyrrolidine ring is crucial. We found simple methods for determining the relative stereochemistry of these compounds on the basis of the (1)H NMR chemical shifts of H-2 and H-4 in D(2)O solution. The signals of H-2 appear at fields higher than 4.2 ppm when the compounds have 2,3-trans stereochemistry whereas, in the 2,3-cis compounds, they appear lower than 4.2 ppm, irrespective of the C-4 substituent. This criterion holds when the solution is in the range of pD 3-8. Moreover, when an epimeric pair at C-2 is available and the spectra are recorded at the same or nearly equal pD, the H-2 chemical shift of the 2,3-trans isomer is higher than that of the corresponding 2,3-cis isomer. ...

British Library Electronic Table of Contents (United Kingdom)

Feasibility of using fixed bed column of conventional ion exchangers/sorbent and chemical precipitation based processes have been examined for the effective removal of the very low levels of 106Ru activity from NH4NO3 effluent generated during wet processing of rejected sintered depleted uranium fuel pellets. Based on the results, a simple process involving precipitation of cobalt sulphide along with ferric hydroxide was selected and further optimization of process variables was carried out. The optimized process has been found to be highly efficient in reducing 106Ru activity down to extremely low levels.

British Library Electronic Table of Contents (United Kingdom)

Abstract Poly(butylene terephthalate) (PBT) composites containing multiwalled carbon nanotubes (MWCNTs) were prepared using a melt-blending process and used to examine the effects on the composite structure and properties of replacing PBT with acrylic acid-grafted PBT (PBT-g-AA). PBT-g-AA and multihydroxyl-functionalized MWCNTs (MWCNTs-OH) were used to improve the compatibility and dispersibility of the MWCNTs within the PBT matrix. The composites were characterized morphologically using transmission electron microscopy, and chemically using Fourier transform infrared, solid-state 13C NMR and UV-visible absorption spectroscopy. The antibacterial and electrical conductivity properties of the composites were also evaluated. MWCNTs or MWCNTs-OH enhanced the antibacterial activity and electric...

British Library Electronic Table of Contents (United Kingdom)

Extraction of 25 L fermentation broth of the newly isolated Streptomyces sp. strain TN58 and various separation and purification steps led to the isolation of five bioactive metabolites, namely brevianamide F (C1), reported from a streptomycete for the first time, N?-acetyltryptamine (C2), thiazolidomycin (C3), and two rhamnopyranosides (C4 and C5). These two rhamnopyranosides were produced directly, without precursor addition. The chemical structure of these five active compounds was established on the basis of 1H, 13C/APT and 2D NMR spectra, ESI and EI-MS data, and by comparison with data from the literature. According to the biological studies, we show in this work that the compounds C1, C2, C4 and C5 possess antimicrobial activities.

British Library Electronic Table of Contents (United Kingdom)

An important aspect of ecosystem sustainability is the ability to withstand and recover from disturbance or stress. In this study, we investigated the effect of a heat-disturbance on soil microbial biomass, microbial activity in response to the addition of organic acid (malate), and microbial community structure in a laboratory experiment. The soils investigated were from a jarrah (Eucalyptus marginata) forest that had undergone rehabilitation following bauxite mining 12 years previously. Soils from a full factorial of two field treatments; contour ripping induced micro-topography (mound or furrow) and prior exposure to prescription fire (burnt or non-burnt), were sampled and found to exhibit treatment-dependent differences in soil biological and chemical properties. Exposure of soil micro...

Energy Technology Data Exchange (ETDEWEB)

Reinforced (heterogel) silicate materials containing an amorphous and a crystalline phase are being used more and more industry. Such systems are energetically unsaturated and therefore promising for use in catalysts. The authors used two reinforced materials as supports: an aluminosilicate containing a zeolite (the cracking catalyst, tseokar) and asbestos-containing aluminosilicate. The active component was introduced by impregnation, and this was followed by heat treatment during which the chemical composition and porous structure were formed. The impregnating mixture consisted of solutions of potassium sulfate and vanadate of the required concentrations. The testing shows that reinforced heterogel systems are promising as support materials for sulfuric acid catalysts.

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In an effort to improve the extrapolation of laboratory data to man and estimate risk of human reproductive toxicity associated with environmental exposure, the pharmacokinetic parameters of the testicular compartment are being studied. Of particular interest is the variety of enzyme systems capable of activating and detoxicating environmental chemicals and drugs. This report compares the metabolism of benzo(a)pyrene by the isolated perfused testis and testicular homogenates in vitro. The cell free in vitro system metabolized benzo(a)pyrene at a much greater rate than the perfused testis and produced a different spectrum of metabolites. Reliable laboratory prediction of biotransformation by the whole organ or intact animal is an essential aspect of reproductive toxicology.

International Nuclear Information System (INIS)

We estimate the optimum electric field at the sheath edge and the minimum interval among the nanotubes to promote the growth of armchair-type nanotubes (metallic character) as a function of the tube length. On the basis of the electric charge distribution in a nanotube and the optimum electric filed E*_1 at the tip of a nanotube evaluated using the Hueckel-Poisson method, we calculate the structure of the electric field lines outside a nanotube in the sheath region. As the tube length increases, the E*_1 decreases. To maintain the chemical activity at the tip, the sheath electric field must be decreased. We show the decreasing rate of the sheath field to the tube length.

International Nuclear Information System (INIS)

Problem areas in BWRs, PWRs and PHWRs, from the viewpoint of chemistry, and the problem of fission product release in nuclear reactors are discussed. These problem areas are : fuel performance, off-normal water chemistry due to condenser leaks, the transport and deposition of the activated corrosion and fission products, denting in steam generators (in the case of PWRs), ingress of air in the cover gas helium and consequent radiolysis of D_2O in the moderator circuit (in the case of PHWRs). (M.G.B.).

CERN Document Server

As an International Organization, one the most important issues that CERN has to respect and guarantee is the protection of the environment. Several of ST activities and operations have a direct impact on the environment: civil engineering works, electrical (transformers) and air-cooling operation, chemical products storage, various waste disposal etc.... Important measures, taken in the past, have to be kept and new ones should be applied in order to insure the conformity of the infrastructure with existing legislation, the correct operation of equipment and systems, the constant monitoring of the different situations and the traceability of the events. Moreover good management of the environment would bring large savings to CERN.

Science.gov (United States)

This paper is dedicated to the treatment of sludge occurring in frame of the Egyptian produced from oil and gas production. The activity levels of three radium isotopes: Ra-226 (of U-series), Ra-228 and Ra-224 (of Th-series) in the solid TENORM waste (sludge) were first evaluated and followed by a sequential treatment for all radium species (fractions) presented in TENORM. The sequential treatment was carried out based on two approaches 'A' and 'B' using different chemical solutions. The results obtained indicate that the activity levels of all radium isotopes (Ra-226, Ra-228 and Ra-224) of the environmental interest in the TENORM waste sludge were elevated with regard to exemption levels established by IAEA [International Atomic Energy Agency (IAEA), International basic safety standards for the protection against ionizing radiation and for the safety of radiation sources. GOV/2715/Vienna, 1994]. Each approach of the ...

Energy Technology Data Exchange (ETDEWEB)

Chemical-looping combustion is a two-stage process proposed as an alternative for the combustion of carbonaceous materials, such as natural gas or coal gas, for almost complete CO{sub 2} capture. In the reduction stage, the structural oxygen contained in the lattice of a reducible inorganic oxide, is used for combustion of the carbonaceous material. In the regeneration stage the oxygen carrier, found in a reduced state after the reduction stage, is regenerated with pure air to recover the physical and chemical properties of the carrier, ready to reinitiate a new cycle reduction-regeneration. In a typical multicycle reactor test, the carriers are subjected to accumulative chemical and thermal stresses and the performance will, probably, decay progressively with the number of cycles. The occurrence of some side reactions may limit the efficiency of the overall process in CO{sub 2} capture. In this paper, titania-supported ...

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

International Nuclear Information System (INIS)

Genes encoding mutants of the thymine photodimer repair enzyme from bacteriophage T4 (T4 endonuclease V) having an amino acid substitution (T127M, W128A, W128S, Y129A, K130L, Y131A, Y132A) were constructed by use of a previously obtained synthetic gene and expressed in Escherichia coli under the control of the E. coli tryptophan promoter. An in vitro assay of partially fractionated mutant proteins for glycosylase activity was performed with chemically synthesized substrates containing a thymine photodimer. T127M and K130L showed almost the same activity as the wild-type protein. Although W128S, Y131A, and Y132A were slightly active, W128A and Y129A lost activity. The results indicated that the aromatic amino acids around position 130 may be important for the glycosylase activity. Mutant T127M was purified, and the Km value was found to be of the same order as ...

International Nuclear Information System (INIS)

At the Borssele Nuclear Power Station, which has been in operation since 1973, a comprehensive program of modifications, one of the most extensive of its kind worldwide, was conducted in 1997 within the framework of an integral safety evaluation carried out at ten-year intervals, especially in the nuclear section. The collective dose associated with this activity was greatly reduced by Alara measures, one of which was chemical decontamination of part of the emergency and residual heat removal systems. An average decontamination factor (DF) of 17 was achieved by using the Siemens Cord UV process. Two decontamination cycles were required. The decontamination program took three days to be completed. The planned collective dose was reduced from 1029 mSv (without decontamination) to 335 mSv (on the basis of a DF of 8). Based on the DF of 17 achieved, the planned dose was corrected downward to 270 mSv. The dose finally achieved was 118 mSv. A total ...

Energy Technology Data Exchange (ETDEWEB)

The dry desulfurization, denitrification and air toxics removal process using activated coke (AC) has been commercially adapted for flue gas clean up of a power plant, an oil refinery plant, an iron ore sintering plant, and a refuse incinerator. This process can achieve 100% removal of SO{sub x}, over 80% removal of NO{sub x} and effective removal of air toxics such as Hg, HCL, dioxines, etc., by contacting flue gas with AC and injecting NH{sub 3} for DeNO{sub x} at temperature range of about 100-200{degrees}C. For flue gas treatment, AC has several functions, which basically depends on the chemical surface group on AC inner surface. As adsorbent, AC can adsorb SO{sub x} at the relatively basic oxygen group site, where the adsorbed SO{sub x} is stored as sulfuric acid into micropore structure of AC. As catalyst, AC can decompose NO{sub x} catalytically with addition of NH{sub 3}. The catalytic activity (NO{sub x} removal ...

British Library Electronic Table of Contents (United Kingdom)

Emerging evidence suggests that E3 ligases play critical roles in diverse biological processes, including innate immune responses in plants. However, the mechanism of the E3 ligase involvement in plant innate immunity is unclear. We report that a rice gene, OsBBI1, encoding a RING finger protein with E3 ligase activity, mediates broad-spectrum disease resistance. The expression of OsBBI1 was induced by rice blast fungus Magnaporthe oryzae, as well as chemical inducers, benzothiadiazole and salicylic acid. Biochemical analysis revealed that OsBBI1 protein possesses E3 ubiquitin ligase activity in vitro. Genetic analysis revealed that the loss of OsBBI1 function in a Tos17-insertion line increased susceptibility, while the overexpression of OsBBI1 in transgenic plants conferred enhanced resi...

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Dopant-free Bi{sub 2}Ti{sub 2}O{sub 7} thin films with pyrochlore structure and La-doped bismuth titanate thin films have been fabricated by means of chemical solution decomposition, and characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy and UV-Vis spectrophotometry in this study. Their photocatalytic activities have been evaluated by photodegrading methyl orange solution, and the optimum processing parameters for the highest photocatalytic activity have been found. Moreover, the effects of La-doping on the phase transformation and the photocalalytic activity have been studied. It has been deduced from the experiment result that substituted La{sup 3+} ions can act as a stabilizer of Aurivillus phase BLT and a grain-growth inhibitor in BLT thin films.

Energy Technology Data Exchange (ETDEWEB)

The Pacific Northwest National Laboratory (PNNL) operates a number of research and development (R and D) facilities for the Department of Energy on the Hanford Site. According to DOE Order 5400.1, a Facility Effluent Monitoring Plan is required for each site, facility, or process that uses, generates, releases, or manages significant pollutants or hazardous materials. Three of the R and D facilities: the 325, 331, and 3720 Buildings, are considered major emission points for radionuclide air sampling and thus individual Facility Effluent Monitoring Plans (FEMPs) have been developed for them. Because no definition of ''significant'' is provided in DOE Order 5400.1 or the accompanying regulatory guide DOE/EH-0173T, this FEMP was developed to describe monitoring requirements in the DOE-owned, PNNL-operated facilities that do not have individual FEMPs. The remainder of the DOE-owned, PNNL-operated facilities are referred to as Balance-of-Plant (BOP) ...

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Los Alamos National Laboratory is subject to annual emissions-reporting requirements for regulated air contaminants under Title 20 of the New Mexico Administrative Code, Chapter 2, Part 73 (20.2.73 NMAC), Notice of Intent and Emissions Inventory Requirements. The applicability of the requirements is based on the Laboratory's potential to emit 100 tons per year of suspended particulate matter, nitrogen oxides, carbon monoxide, sulfur oxides, or volatile organic compounds. For calendar year 2001, the Technical Area 3 steam plant was the primary source of criteria air pollutants from the Laboratory, while research and development activities were the primary source of volatile organic compounds. Emissions of beryllium and aluminum were reported for activities permitted under 20.2.72 NMAC. Hazardous air pollutant emissions from chemical use for research and development activities were also reported.

Energy Technology Data Exchange (ETDEWEB)

This quarterly report for the period April through June 1984 summarizes activities in Sandia National Laboratories' continuing program of coal liquefaction research. The primary goals are to: explore novel catalytic concepts and materials for conversion of coal to liquid fuels; determine the effects of process variables on catalyst deactivation; determine the effects of coal structure and solvent properties on low temperature dissolution; study the kinetics and catalysis of hydrogen transfer reactions; develop an understanding of slurry gelling phenomena; and provide a technical assessment of coal liquefaction processes. During this period, work was performed on: analysis of catalyst samples from Wilsonville Run 246; catalyst presulfiding; catalyst activity testing using pyrene as a chemical probe; catalyst deactivation using a high-pressure model compound test reactor; dissolution chemistry of Wyodak coal; slurry ...

Energy Technology Data Exchange (ETDEWEB)

The carbon transfer has been analyzed in the Alloy 800/sodium/stainless steel system by determining the carbon-uptake of Alloy 800 foils, which were exposed in liquid sodium of known carburizing potential. Under equilibrium conditions between 650 and 550/sup 0/C the measured total carbon concentrations in the Alloy 800 tabs were found to be roughly related to the carbon activities of the sodium environment by the equation already stated for the 18 Cr-8/10 Ni stainless steels, extrapolated to the chemical composition of the Ni-rich austenitic alloy. However the Alloy 800 was not found to undergo any decarburization in low-carbon activity environments. The carbon diffusion kinetics was determined as a function of temperature, it was found to be similar to that reported for the AISI-304 type of steel. The effects of sodium exposure on microstructural and mechanical properties of several Alloy 800 heats were examined at 550/sup ...

Energy Technology Data Exchange (ETDEWEB)

The passive films formed in stainless steels are thin and fine oxide films, a high corrosion resistance can be provided by these films. This study formed SiO2 protective coating on the substrate of SUS 304 stainless steels by chemical vapor deposition using TEOS-O3 system. Firstly, relations of substrate temperature and deposition rate of films, chemical composition, refractive index of films were investigated. Then, the corrosion resistance of SUS 304 stainless steels coated SiO2 films was examined by activation time and an anodic polarization curve in 1 kmol[center dot]m[sup -3] HCl solution. The results were obtained as follows. Thickness of SiO2 films linearly increases with time at the deposition temperature of 473 to 673 K. Si-OH bonds would disappear above the deposition temperature of 573 K, almost perfect SiO2 films were obtained. The activation time in 1 kmol[center dot]m[sup -3] HCl solution ...

Energy Technology Data Exchange (ETDEWEB)

The Phase I feasibility study has focused on determining the availability of information for estimating exposures of the public to chemicals and radionuclides released as a result of historical operation of the facilities at the Oak Ridge Reservation (ORR). The estimation of such past exposures is frequently called dose reconstruction. The initial project tasks, Tasks 1 and 2 were designed to identify and collect information that documents the history of activities at the ORR that resulted in the release of contamination and to characterize the availability of data that could be used to estimate the magnitude of the contaminant releases or public exposures. A history of operations that are likely to have generated off-site releases has been documented as a result of Task 1 activities. The activities required to perform this task involved the extensive review of historical operation records and ...

Science.gov (United States)

Mesporous anatase-phase TiO(2) hollow spheres with high photocatalytic activity were prepared by hydrothermal treatment and self-transformation of amorphous TiO(2) solid spheres in an NH(4)F aqueous solution. The prepared samples were characterized by X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, N(2) adsorption-desorption isotherms and UV-vis absorption spectroscopy. The photocatalytic activity was evaluated by photocatalytic oxidation decomposition of acetone in air under UV irradiation. It is found that F(-) plays an essential role in the formation of TiO(2) hollow spheres. F(-) not only induces the hollowing of TiO(2) solid spheres, but also promotes the crystallization of anatase TiO(2) nanocrystals. A possible formation mechanism for the TiO(2) hollow spheres by localized Ostwald ripening or chemically induced self-transformation is proposed based on the ...

International Nuclear Information System (INIS)

For prolonged storage and eventual disposal radioactive wastes will be solidified to reduce the problems which accompany liquid waste whilst solid wastes will be encapsulated in an immobilising matrix. In the solidification and encapsulation process it will be important to produce a material in a form which is chemically stable, mechanically strong and which will not react with or allow free passage of groundwater. To this end a continuous check will be required to ensure that the various wastes are chemically compatible with the solidifying and binding matrices and that the associated processes are performed against a strict Quality Programme. The Quality Programme will be extensive requiring the specification of procedures for assessing the quality and nature of the wastes, the detailed operation of the solidification and/or encapsulation, the overpack requirements for transportation and the routines to be adopted with respect to storage or ...

Energy Technology Data Exchange (ETDEWEB)

Activities of the Referenzlaboratorium Reinhaltung der Luft at Magdeburg as well as existing air pollution standards in the German Democratic Republic are reviewed. The laboratroy coordinates research and standardization in the field of industrial air pollution for the Ministry of Health. The standards provide orientation for emission control by state district health inspectorates. Emission limits (in g/m/sup 3/) which are international standards for 15 selected industries are listed. Emission limits (in g/m/sup 3/) of GDR standards, issued between 1971 and 1984 are also provided. They concern emission of brown coal dust from coal preparation plants, dust and chemical compound emission from metallurgical plants, dust emission from plants of the limestone and cement industry as well as from cupola furnace plants, boiler plants, plants of the wood industry and road asphalt mixing. Six additional standards which entered effect between 1984 and ...

International Nuclear Information System (INIS)

In developing new brain imaging agents for single photon emission computed tomography (SPECT), we synthesized eleven radioiodinated phenoxyacetic acid derivatives and investigated the relationship between the chemical structure and in vivo characteristics. Biodistribution studies in mice revealed high initial brain uptake for all the compounds. Blood radioactivity level depended markedly upon the chemical stability of the compound. The #alpha#,#alpha#-dimethylester derivative (1e), amide derivatives (2a-c) and diamine derivatives (3a, b, 4), which were stable to hydrolysis, showed low blood activity levels following i.v. administration. Disappearance of the ester and amide compounds from the brain was rapid. However, the diamine derivatives displayed improved retention in the brain. Compounds 3a and 4 possessed the best combination of high brain uptake and sufficient retention to be useful as potential brain imaging ...

Energy Technology Data Exchange (ETDEWEB)

The authors have discovered chert xenoliths from green rocks in the Pippu area, central Hokkaido, Japan. Reports were given on the discovery with regard to the state of its production, chemical composition of the green rocks, and radiolarian fossils produced from the chert and their age. Considerations were given on the geological significance thereof. On 23 green rocks and five cherts out of the collected samples, rock slices were prepared, and petrographic statement was made by using a polarizing microscope. In addition, the whole petro-chemical composition analysis was performed on green rocks to discuss the radiolarian fossils and geological ages. The following conclusions were obtained as a result: green rocks may be identified as a product of igneous activities in a large plate in a certain period from the latter Callovian period of the middle age of the Jurassic period to the Barremian period of the Paleozoic era in ...

International Nuclear Information System (INIS)

Micronutrient deficiencies in flooded rice have been recognized with increasing frequency in recent years. Zinc deficiency is the most widespread disorder, followed by Fe, Mn, and Cu deficiencies. Boron and Mo deficiencies have not been reported in field culture. The peculiar characteristics of a flooded soil are: 1) a layer of standing water; 2) absence of oxygen; 3) a soil profile largely in a reduced chemical state; 4) the presence of large biological carbon dioxide excesses; 5) the presence of high concentrations of soluble Fe"+"+ and Mn"+"+; 6) alteration of soil pH; 7) the presence of toxic substances; 8) increased soluble Na"+, K"+, Ca"+"+, Mg"+"+, NH_4"+, HCO_3"-, H_2PO_4"-, and Si(OH)_4 in the soil solution. Micronutrient availability in flooded soils is affected by: 1) increased solubility of relatively insoluble minerals due to dilution effects; 2) pH changes in relation to solubility and plant availability; 3) changes in oxidation-reduction equilibria; ...

International Nuclear Information System (INIS)

PWR steam generators have suffered from a variety of degradation phenomena. This paper identifies the corrosion-related defects and their probable causes and suggests approaches to correct and prevent corrosive activity. In the attempt to solve the degradation problems, research programs have concentrated on modifying materials, stresses, and the chemical environment in both new and operating steam generators. The following corrosion-related defects have been studied: tube wastage, denting, primary side (ID) intergranular stress corrosion cracking (IGSCC), OD-initiated intergranular attack (IGA), pitting, and corrosion fatigue. Plants affected by wastage have greatly reduced their problem by adopting an all volatile treatment (AVT). In the case of denting, a less aggressive chemical environment is recommended. Primary side IGSCC responds to temperature reduction, stress relief, and material improvements, while flushing and ...

Science.gov (United States)

Macromolecular and polyanionic Na(+)-poly(gamma-glutamic acid) (PGA) silver nitrate complex acted as both a metal ion provider and a particle protector to fabricate nanosized silver colloids under chemical reduction by dextrose. The formation and size of particles have been characterized from transmission electron microscopy (TEM), dynamic light scattering analysis and UV-vis spectrophotometer. The results showed that the average particle size was 17.2+/-3.4 to 37.3+/-5.5 nm, apparently depending on the complex concentration. It was found that the rate constant and conversion of silver nanoparticles were proportional to the concentration of PGA. The growth mechanism of nanosized silver colloid was fully discussed. In addition, the in vitro cytotoxicity evaluated by L929 fibroblasts proliferation and antibacterial activity against Gram-positive strain (methicillin-resistant S. aureus (MRSA)) and Gram-negative strain (P. aeruginosa) bacteria have ...

International Nuclear Information System (INIS)

Direct electrochemistry and electrocatalysis of catalase (Cat) was studied based on a nano-composite film consisting of amine functionalized graphene and gold nanoparticles (AuNPs) modified glassy carbon electrode. Graphene was synthesized chemically by Hummers and Offeman method and then was functionalized with amino groups via chemical modification of carboxyl groups introduced on the graphene surface. The nano-composite film showed an obvious promotion of the direct electron transfer between Cat and the underlying electrode, which attributed to the synergistic effect of graphene-NH2 and AuNPs. The resultant bioelectrode retained its biocatalytic activity and offered fast and sensitive H2O2 quantification. Under the optimized experimental conditions, hydrogen peroxide was detected in the concentration range from 0.3 to 600 ?M with a detection limit of 50 nM at S/N = 3. The biosensor exhibited some advantages, such as ...

International Nuclear Information System (INIS)

Laboratory testing at Combustion Engineering has indicated promise in controlling simulated steam generator tube denting through chemical neutralization. Testing was limited to on-line treatment, and two neutralizers have been evaluated: calcium hydroxide and boric acid. On-line treatment with calcium hydroxide successfully halted active denting whenever the bulk calcium concentration (in ppm) equaled or exceeded the bulk chloride concentration (in ppm). Calcium hydroxide also was effective as an alternative to ammonia as a pH controlling agent in two tests conducted without ingress of chloride. On-line treatment with boric acid consisted of a four-day soak at simulated low (approximately 30 percent) power with 50 ppm B followed by one month full-power operation with 10 ppm B. This treatment also halted denting. Nondestructive and destructive examination of test boilers gave no indication of adverse side effects associated with either ...

Energy Technology Data Exchange (ETDEWEB)

The Hanford Site, Richland, Washington, contains over 1,500 identified waste sites and numerous groundwater plumes that will be characterized and remediated over the next 30 years. As a result of the Hanford Federal Facility Agreement and Consent Order, the US Department of Energy (DOE) has initiated a remedial investigation/feasibility study (RI/FS) at the 200-BP-1 operable unit. The 200-BP-1 RI/FS is the first Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) investigation on the Hanford Site that involves highly radioactive and chemically contaminated soils. The initial phase of site characterization was designed to assess the nature and extent of contamination associated with the source waste sites within the 200-BP-1 operable unit. Characterization activities consisted of drilling and sampling, chemical and physical analysis of samples, and development of a conceptual vadose zone model. ...

Energy Technology Data Exchange (ETDEWEB)

Modification of DNA and double-stranded deoxyoligonucleotides with antitumor 1,2-diamino-cyclohexanedinitroplatinum(II) (Pt-dach) complexes was investigated with the aid of physico-chemical methods and chemical probes of nucleic acid conformation. The three Pt-dach complexes were used which differed in isomeric forms of the dach non-leaving ligand-Pt(1R,2R-dach), Pt(1S,2S-dach) and Pt(1R,2S-dach) complexes. The latter complex has lower antitumor activity than the other two Pt-dach complexes. Pt(1R,2S-dach) complex exhibits the slowest kinetics of its binding to DNA and of the conversion of monofunctional binding to bifunctional lesions. The anomalously slow electrophoretic mobility of multimers of the platinated and ligated oligomers suggests that bifunctional binding of Pt-dach complexes to a d(GG) site within double-stranded oligonucleotides induces bending of the oligomer. It is proposed that different effects of the ...

Energy Technology Data Exchange (ETDEWEB)

The relative potencies of 20 polychlorinated biphenyls (PCBs) were studied in a chicken embryo hepatocyte system. The 20 congeners were selected according to a full 2{sup 4}-factorial design based on the principal properties of all 154 tetra- through heptachlorinated PCBs. The principal properties were obtained using principal component analysis (PCA) on a multitude of different physico-chemical properties of the PCBs. Toxic equivalency factors (TEFs) were determined for seven out of the twenty PCB congeners, viz. PCB{number_sign}41, PCB{number_sign}60, PCB{number_sign}78, PCB{number_sign}126, PCB{number_sign}169, PCB{number_sign}190, and PCB{number_sign}193, which elicit measurable catalytic ethoxyresorufin-O-deethylase (EROD) activity in the chicken hepatocytes. A multivariate quantitative structure-activity relationship (QSAR) was developed by using partial least-squares to latent variables (PLS) in order to model the ...

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

International Nuclear Information System (INIS)

The aim of the study is to prepare ionic exchangers using the polymerization of unsaturated polyster with monomeric styrene units in a ratio of 60%: 40% respectively. The type of method involved in this preparation, is called An Emulsion Polymerization. Such type of polymerization was carried out by two techniques: chemical and irradiation techniques. The first techniques requires the formation of free radical monomers by use of methyl Ethy Ketone Peroxide capable of decomposing into free radicals upon heating, while the other technique involves the use of gamma rays (using Co-60 source) capable of activating monomers towards free radical formations. A number of very effective chemical parameters and physical factors were used and investigated throughout the reactions such as: dispersant matrix, viscosity, rate of mixing, and irradiation dose. Besides, the study has included the study of the rate of Resin Beads Swelling ...

Energy Technology Data Exchange (ETDEWEB)

When a shortened enzymatic version of the Tetrahymena self-splicing intervening sequence (IVS) RNA is placed under catalytic conditions and irradiated at 254 nm, a covalent cross-link forms with high efficiency. The position of the cross-link was mapped by using three independent methods: RNase H digestion, primer extension with reverse transcriptase, and partial hydrolysis of end-labeled RNA. The cross-link is chemically unusual in that it joins two adenosines, A57 and A95. Formation of this cross-link depends upon the identity and concentration of divalent cations present and upon heat-cool renaturation of the IVS in a manner that parallels conditions required for optimal catalytic activity. Furthermore, cross-linking requires the presence of sequences within the core structure, which is conserved among group I intervening sequences and necessary for catalytic activity. Together these correlations suggest that a common ...

Energy Technology Data Exchange (ETDEWEB)

For the first time in scientific literature, in our joint work with Dr. G. Ladwig in 1978 it was established phase portraite of the oxide vanadium-phosphorus system within wide range of P/V ratios from 0.5 to 3.2. Some later those data were confirmed. By investigation of the properties of individual vanadium-phosphorus phases it was also shown that the active component of such catalysts in n-butane oxidation was vanadyl pyrophosphate phase (VO){sub 2}Pr{sub 2}O{sub 7}. From then the conclusion has been evidenced by numerous publications and at present it has been out of doubt practically all over the world. It was hypothized that the unique properties of (VO){sub 2}P{sub 2}O{sub 7} in the reaction of n-butane oxidation could be explained by the presence of paired vanadyl groups and nearness of the distances between neighbouring vanadyl pairs and that between the first and fourth carbon atoms in n-butane molecule. The molecule activation occured ...

British Library Electronic Table of Contents (United Kingdom)

The non-isothermal pyrolysis kinetics of Acetocell (the organosolv) and Lignoboost (kraft) lignins, in an inert atmosphere, have been studied by thermogravimetric analysis. Using isoconversional analysis, it was concluded that the apparent activation energy for all lignins strongly depends on conversion, showing that the pyrolysis of lignins is not a single chemical process. It was identified that the pyrolysis process of Acetocell and Lignoboost lignin takes place over three reaction steps, which was confirmed by appearance of the corresponding isokinetic relationships (IKR). It was found that major pyrolysis stage of both lignins is characterized by stilbene pyrolysis reactions, which were subsequently followed by decomposition reactions of products derived from the stilbene pyrolytic pr...

British Library Electronic Table of Contents (United Kingdom)

Eugenol, the principal chemical component of clove oil from Eugenia aromatica has been long known for its analgesic, local anesthetic, anti-inflammatory, and antibacterial effects. The interaction of the eugenol with ten different hydrophobic and hydrophilic antibiotics was studied against five different Gram negative bacteria. The MIC of the combination was found to decrease by a factor of 5-1000 with respect to their individual MIC. This synergy is because of the membrane damaging nature of eugenol, where 1mM of its concentration is able to damage nearly 50% of the bacterial membrane. Eugenol was also able to enhance the activities of lysozyme, Triton X-100 and SDS in damaging the bacterial cell membrane. The hydrophilic antibiotics such as vancomycin and b-lactam antibiotics which have ...

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

International Nuclear Information System (INIS)

The following aspects will be discussed: The main function of the Division of Inspection Services and its role in the Marketing of agricultural products; the shelf life of agricultural products: short review of present methods with a practical example of losses incurred due to limited keeping quality; irradiation and heat treatment: advantages of inhibited microbiological activities and undesirable chemical changes from a quality control point of view; quality standards: the basic principles of quality control; consequences of effective post-harvest treatment: export of deciduous and citrus fruit; the magnitude of the problem of poor keeping quality and quality requirements; other fruit; quantities and export limitations and vegetables; quantity and quality requirements; local marketing: fruit and vegetables subjected to inspection; quantity and quality aspects.

Science.gov (United States)

Before electroless plating, polymer surfaces must be sensitized and/or activated by using either the conventional two-step or one-step process. The latter stage is a compulsory one to make such surfaces catalytic, e.g., for Ni-P deposition. These processes are performed here using O{sub 2}, NH{sub 3}, or N{sub 2} plasma pretreatments. Reaction mechanisms are proposed for each of the processes and for each type of surface considered (oxygenated or both oxygenated and nitrogenated by the plasma treatment). Direct palladium chemisorption onto nitrogenated groups is highlighted. This allows one to simplify the process making the surface catalytic via elimination of the use of SnCl{sub 2} and to extend the method to any polymer. An additional interest of the plasma treatments, besides their high efficiency in grafting chemical functions, is to perform this grafting at will on selected areas which results in selective metallization.

International Nuclear Information System (INIS)

Nuclear approaches for compositional characterization has bright application prospect in forensic perspective towards assessment of nature and origin of seized material. The macro and micro physical properties of nuclear materials can be specifically associated with a process or type of nuclear activity. Under the jurisdiction of nuclear analytical chemistry as well as nuclear forensics, thrust areas of scientific endeavor like determination of radioisotopes, isotopic and mass ratios, analysis for impurity contents, arriving at chemical forms/species and physical parameters play supporting evidence in forensic investigations. The analytical methods developed for this purposes can be used in international safeguards as well for nuclear forensics. Nuclear material seized in nuclear trafficking can be identified and a profile of the nuclear material can be created

Energy Technology Data Exchange (ETDEWEB)

This report describes progress during the first year of a three-year project. The objective of the research is to examine new design approaches for achieving very high conversion efficiencies. The program is divided into two areas. The first centers on exploring new thin-film approaches specifically designed for III-V semiconductors. The second area centers on exploring design approaches for achieving high conversion efficiencies without requiring extremely high quality material. Research activities consisted of an experimental study of minority carrier recombination in n-type, metal-organic chemical vapor deposition (MOCVD)-deposited GaAs, an assessment of the minority carrier lifetimes in n-GaAs grown by molecular beam epitaxy, and developing a high-efficiency cell fabrication process.

Energy Technology Data Exchange (ETDEWEB)

Kinetics of postradiation polymerization of triethylene glycol ..cap alpha.., ..omega..-dimethacrylate has been studied by calorimetric method. The low-temperature radiolysis has been studied by ESR method. The radiation-chemical yield of radicals on ..gamma..-irradiation by /sup 60/Co is determined being equal to 6+-1 1/100 ev. Transformation of the radicals spectrum into the spectrum of propagating macroradicals proceeds at 140 K. After the transition from glassy to liquid state (Tsub(g)=193 K) the intensive postpolymerization begins. During the polymerization the disappearance of radicals is observed. For the low-temperature region the effective activation energy of polymerization is determined beina equal to 50.7+-0.8 kJ/mol.

CERN Document Server

An effect of laser-cooling of water was observed for the first time with a temperature decrease dT = -2.2 K after irradiation of liquid water surface by a powerful Ar-Xe pulse laser with a pulse energy of about 1 J and wavelength L = 1.73, 2.63 and 2.65 um. The discovered effect can apparently be ascribed to the optical excitation of vibrational states of H2O molecules followed by an endothermic consolidation of chemically active excited molecules into a quasi-stable cluster-like structure. The measured time dependences of the cooling effect show that a typical life time of the new state of water amounts to hours. It has also been shown that the life time of the excited vibrational molecular states due to a radiation trapping effect can be estimated to at least hundreds of seconds.

British Library Electronic Table of Contents (United Kingdom)

This work investigated the inactivation of Microcystis aeruginosa (MA) with contact glow discharge electrolysis (CGDE). The influences of applied voltage, current and treatment time on the inactivation rate were critically examined. Based on the above results, the optimal conditions were chosen to sufficiently utilize chemically active species and enhance the inactivation of MA. Under the optimal conditions (voltage: 530?V; current: 30?mA; treatment time: 20?min), the inactivation rate of algae was more than 90% within 5?days incubation after inoculating. At the same time, the concentrations of Chlorophyll-a and dehydrogenase decreased, which demonstrated that 20?min CGDE treatment could effectively inhibit the growth of MA and caused deterioration of cell integrity. The present work would...

British Library Electronic Table of Contents (United Kingdom)

The comprehensive theoretical and experimental study of the adsorption of water and methanol molecules on active sites (carboxyl and phenol hydroxyl groups) on the graphitized thermal carbon black is performed. It is shown that microclusters formed upon the adsorption of these molecules on such sites are characterized by the cyclic structure comprising 4?5 molecules similar to that whose existence was revealed previously in liquid water and on the surface of silver iodide. The analysis of the studied adsorption clusters demonstrated that the formation of such cycles is governed primarily by the hydrogen bonding; however, a definite role is played also by energy effects associated with the changes in the state of molecular motion during adsorption. It is shown that the generalized Langmuir ...

British Library Electronic Table of Contents (United Kingdom)

The leaf extract from the plant Piliostigma reticulatum was found to exhibit antimicrobial activity against some bacteria and fungi such as Staphylococcus aureus (NCTC 6571), Escherichia coli (NCTC 10418), Bacillus subtilis (NCTC 8236), Proteus vulgaris (NCTC 4175), Aspergillus niger (ATCC 10578) and Candida albicans (ATCC 10231). Upon investigation of the chemical constituents present in the leaf extract, a total of seven compounds were isolated and their structures were unambiguously established by spectroscopic methods including HR-MS and NMR spectrometry. Four of the isolated compounds were novel, namely 6-C-methyl-2-p-hydroxyphenyloxychromonol (piliostigmol), 1, 6,8-di-C-methylquercetin-3,3prime,7-trimethyl ether, 2, 6,8-di-C-methylquercetin-3,3prime-dimethyl ether, 3 and 3prime,6,8,-...

Energy Technology Data Exchange (ETDEWEB)

This article describes the chemical preparation of petroleum additives of the MASK type from samples of concentrated alkylsalicylic acids. The obtained additives contain high contents of calcium alkylsalicylate and respective total alkalinities of 156, 131, and 130 mg KOH/g. Sodium alkylsalicylate concentrates, obtained in the form of an aqueous acetone solution, were converted to alkylsalicylic acids by interaction with hydrochloric acid. The solvent was removed from the upper and lower layers by distillation, and the resulting products were analyzed by liquid chromatography. Service tests were performed on a model formulation of the additive in M-11 oil in a Petter AV-1 test stand unit in comparison with commercial MASK additive. The results indicate that the model additive formulation gives approximately the same corrected piston fouling ratings as the commercial additive.

International Nuclear Information System (INIS)

The activities "1"0"1Mo and "1"0"1Tc produced from neutron capture by natural Mo were chemically separated and studied using Ge(Li) #gamma#-ray detectors. Out of 185 transitions observed in the decay of "1"0"1Mo, 170 were assigned to 44 excited levels in "1"0"1Tc. For the decay of "1"0"1Tc, 26 of 27 transitions were placed among 10 excited levels in "1"0"1Ru. The interpretation of the "1"0"1Tc level scheme using the shell-model approach is not satisfactory even for a five-particle calculation. Systematics of odd-A level structures in the region of A=101 indicate that the level structure of "1"0"1Tc could be due partly to the onset of collective effects.

Energy Technology Data Exchange (ETDEWEB)

Japanese companies have developed suitable cleansing technologies and export their know-how. Some original technologies are developed today, like: in-situ chemical oxidation, iron confinement, hot-soil process, low-temperature catalytic decomposition or dechlorination of dioxins. However, some pollutions are still poorly considered (nitrates) or badly mastered (dioxins). This situation is partly due to late legal decisions and to limited pollution abatement measures. Japan is also very active in bio-cleansing research, and this, despite the lack of dialogue and directives at the national level. Several research programs with important funds have started since 1995. However, Japan is still at the preliminary stage in open-field applications of cleansing methods. (J.S.)

Energy Technology Data Exchange (ETDEWEB)

As an integral part of DOE/GTD's Brine Injection Program, LBL is developing and demonstrating methods for: (1) designing and analyzing injection tests, (2) predicting and monitoring migration of injected fluids, and (3) optimizing field-wide injection and heat extraction operations in geothermal reservoirs. Computational and well test techniques are being developed (a) to detect and predict the movement of fluids of contrasting temperatures, phase compositions and chemistries in the injected formation, and (b) to characterize the associated physical and chemical processes occurring in the reservoir. LBL's theoretical and field-related brine injection activities in FY 1986 are described, and progress made during FY 1987 is discussed.

Energy Technology Data Exchange (ETDEWEB)

The results of a study on the application of remote sensing and geophysical methods for the detection and monitoring of acid mine drainage (AMD) are summarized, with emphasis on those that appear most suitable. The study consisted of a literature review, an information survey of users and suppliers, and discussions with various experts. Space-borne sensors, airborne sensors, airborne videography and digital frame cameras, spectroradiometers, radar, and photographic data are considered. Geophysical methods are effective for measurement of sulphides, areas of active chemical oxidation, acid mine drainage, and contaminated ground water movement. The popularity and effectiveness of various geophysical methods are rated for AMD applications. 25 refs., 1 fig., 3 tabs.

British Library Electronic Table of Contents (United Kingdom)

Known since ancient times, the phenomenon of allelopathy has recently received greater attention from researchers and farmers worldwide. Crop failures and low yields caused by the reseeding, overseeding, crop rotation and replanting of fruit trees in orchards are believed to be caused by allelopathic activity. Moreover, the expensive and environmentally impacting herbicides for weed control have motivated studies directed at developing cheaper, environmentally-friendly alternatives. Despite the difficulties in separating chemical interference from other mechanisms, more modern approaches have produced consistent and conclusive data on this topic. The release and dynamics of allelochemicals in the soil are discussed herein. Examples of allelopathic crops, the allelochemicals produced and th...

Science.gov (United States)

In the Advance Coal Liquefaction Concept Proposal (ACLCP) carbon monoxide (CO) and water have been proposed as the primary reagents in the pretreatment process. The main objective of this project is to develop a methodology for pretreating coal under mild conditions based on a combination of existing processes which have shown great promise in liquefaction, extraction and pyrolysis studies. The aim of this pretreatment process is to partially depolymerise the coal, eliminate oxygen and diminish the propensity for retograde reactions during subsequent liquefaction. The desirable outcome of the CO pretreatment step should be: (1) enhanced liquefaction activity and/or selectivity toward products of higher quality due to chemical modification of the coal structure; (2) cleaner downstream products; (3) overall improvement in operability and process economics.

International Nuclear Information System (INIS)

This paper shows how molecular theory paves the way for accelerated aging tests of safety-related equipment in nuclear power plants, as required by NRC qualification programs. Arrhenius' model, based on an equation, provides useful information regarding the extent of molecular change as a function of time and temperature. Critical to determining the aging characteristics and qualified life of organic materials is the activation energy concept, which is derived from information gathered when the molecular reaction of the material is documented over the entire life cycle. In accelerated-aging applications, the importance of the model lies in characterizing the chemical related reactions of materials. The problem with the Arrhenius approach is that, in generating a testing period of reasonable duration, a rather high test temperature must be selected which may lead to an added and unrelated environmental effect.

British Library Electronic Table of Contents (United Kingdom)

Nowadays there are many sun-protection cosmetics incorporating organic or inorganic UV filters as active ingredients. Chemically stable inorganic sunscreen agents, usually metal oxides, are widely employed in high-SPF (sun protection factor) products. Titanium dioxide is one of the most frequently used inorganic UV filters. It has been used as a pigment for a long period of cosmetic history. With the development of micronization techniques, it has become possible to incorporate titanium dioxide in sunscreen formulations without the previous whitening effect, and hence its use in cosmetics has become an important research topic. However, there are very few works related to quantitation of titanium dioxide in sunscreen products. In this research, we analysed the amounts of titanium dioxide i...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared

Energy Technology Data Exchange (ETDEWEB)

Short communication. 3 refs.

Science.gov (United States)

No abstract prepared.

Science.gov (United States)

No abstract available.

Medline Plus

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

International Nuclear Information System (INIS)

There are two major distinct activities involved with reprocessing of nuclear fuel. They are: a) Mechanical handling of the fuel in the head end plants; and b) chemical dissolution and separation of unused fuel, useful by-products and waste products. Plants and facilities associated with the former include significant remote handling equipment that is designed for handling of fuel for normal production processes. These equipment are selected and designed to meet the design throughput of the plant taking into consideration ease of their operation and maintenance in conjunction with statutory regulations on safety and operator dose uptake. Nevertheless, during the life of the plant, there are instances when special equipment is called for to access part of the plant and undertake tasks such as inspection, maintenance and modification to improve the existing process. BNFL has much experience in the design and application of remote handling ...

International Nuclear Information System (INIS)

The "6"2Zn-"6"2Cu generator system is one of the few which yield a pure positron emitting daughter. The authors have developed a method for the preparation of this generator system following 32 MeV #alpha# particle bombardment of nickel targets. The chemical processing involves two stages: first a hydrous zirconium oxide column is used at pH 4-5 to separate the zinc and copper activities produced in the target nickel, and secondly, a conventional anion exchange column is used to retain the "6"2Zn and remove all copper activities in 2M HCl. This column serves as the "6"2Cu generator which will yield pure "6"2Cu repeatedly, free from "6"2Zn and other impurities, in a mixture of HCl and NaCl. A method is outlined also to obtain a solution of "6"2Zn using the hydrous zirconium oxide (HZO) column. "6"1Cu can be prepared as a by-product in the above procedure, but a method for the preparation of "6"1Cu alone using an 18 MeV ...

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 is an austenitic Fe-Ni-Cr steel containing relatively minor but important amounts of carbon, aluminium and titanium. Special grades of alloy 800 known as 800H, 800HT and 800LC differ in the concentrations of these elements. In addition to these industrial specifications, further melts were prepared containing phosphorous or sulphur. Using a radioactive tracer method the bulk and grain-boundary diffusion of {sup 59}Fe was investigated in these alloys in the temperature range 800 to 1000 C. For evaluation of the diffusion profiles the approximation of Suzuoka was used, which considers the depletion of the tracer on the surface. By autoradiography it was confirmed that such depletion occurs. In alloy 800H the activation energy of grain-boundary diffusion of {sup 59}Fe was found to be (209{+-}17) kJ/mol; dissolved elements, especially phosphorous, increase the activation energy. The same materials - aged at 800 C for 100 h - were used for ...

Energy Technology Data Exchange (ETDEWEB)

Using a radioactive tracer method the bulk and grain boundary diffusion of {sup 59}Fe was determined in industrial alloy 800 and melts of alloy 800 with additional P and S in the temperature range 800 to 1000 C. The use of the approximation of Suzuoka was confirmed by autoradiographs. In alloy 800 H the activation energy of grain boundary diffusion of {sup 59}Fe is (209 {+-} 17)kJ/mol. Dissolved elements especially P increase the activation energy of the grain boundary diffusion of Fe by their segregation to the grain boundaries. In addition the influence of the grain boundary diffusion on the growth of creep cavities was investigated in the same materials, and the chemical composition of the creep cavities and grain boundaries were analysed by Auger electron spectroscopy (AES). For alloy 800 + 0.088 wt-%P an enrichment of about 14 at-%P was observed at the grain boundaries. The addition of P clearly enhances the creep ...

International Nuclear Information System (INIS)

In this paper, we present the results of Plasma-Enhanced Chemical Vapor Deposition gate-oxide (SiO_2) integrity on ELC (excimer-laser-crystallized), MILC (metal-induced lateral-crystallized) and SPC (solid-phase-crystallized) polysilicon films. We observed that gate oxide strength of poly-Si TFT strongly depends on the crystallization method for the active silicon layer. In the case of ELC films, asperities on the silicon surface reduce the SiO_2 breakdown field significantly. The metallic contaminants in MILC films are responsible for a deleterious impact on gate oxide integrity. Among the three cases, the SiO_2 breakdown field was the highest for the SPC silicon films. The breakdown fields at the 50 % failure points in Weibull plots for the ELC, MILC and SPC cases were 5.1 MV/cm, 6.2 MV/cm, and 8.1 MV/cm, respectively. We conclude that the roughness and metallic contamination of the poly-Si films are the main factors that cause enhanced ...

International Nuclear Information System (INIS)

Maytenus ilicifolia Mart. ex Reissek is traditionally used in Brazil for treatment of gastric ulcers. Here we report the phytochemical investigation of an ethanol extract of M. ilicifolia leaves (EEMIL) aiming at the isolation of constituents which were used as chemical markers to monitor an activity-guided fractionation of a lyophilized aqueous extract of M. ilicifolia leaves (LAEMIL). From EEMIL, four flavonoids were isolated, namely the tri-flavonoid glycosides mauritianin (1), trifolin, (2) hyperin (4), and epi-catechin (5). Fractionation of LAEMIL led to 5 fractions which afforded the tetra-glycoside kaempferol derivative (3), and galactitol (6). LAEMIL and its fractions were evaluated in rats for their effects on gastric secretion volume and pH. HPLC (High Performance Liquid Chromatography) analysis revealed that only fractions containing the tri- and tetra-flavonoid glycosides 1 and 3 caused significant increase of gastric volume and pH, ...

Energy Technology Data Exchange (ETDEWEB)

The present work's objective is to test sampling methodologies applied on the bioremediation processes in situ, involving the establishment of sample replicates, specific laboratory procedures and its results, inedited on the referred technique. Agricultural fertilizers were used, NPK and OSMOCOTE, as biostimulants on mangroves substrates affected by petroleum activities. The tested methodology used on the experiment was based on the monitoring of this technology in aquarium with water from Sao Paulo's river and sediment contaminated by oil, realized in three steps (first pre-test, second pre-test and third pre-test) that happened between the months of August and November of 2007. The physical-chemical parameters were measured with portable devices carefully calibrated and the oil analyzed with gas chromatography. The saturated hydrocarbons (n-alkenes) had an increase on the concentrations for some aquariums and these found ...

Energy Technology Data Exchange (ETDEWEB)

The adsorption of mercury vapor on particles was studied by using soot particles generated by incineration of sewage sludge (EP-ash) and activated carbon particles. Through the experiments, it was found that, at 298 K, the EP-ash has a fairly high adsorption capacity for mercury vapor in the order of 10/sup -6/g/g, which is between that of the ordinary soils and that of activated carbon particles. Furthermore, it was found that physical adsorption of mercury vapor on the studied particles at high temperature is described by Dubinin's equation. On the basis of the equation, it was shown that EP-ash physically adsorbs very little mercury at high temperature, and therefore, most mercury in the EP-ash is chemically adsorbed or contained in a form of mercury compounds. Nevertheless, the total amount of mercury contained in the particles is very little compared to the total mercury in the exhaust gases so that most ...

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.

International Science & Technology Center (ISTC)

Development of biological preparation with surfactant activity

Energy Technology Data Exchange (ETDEWEB)

Gas-insulated systems employing SF/sub 6/ are utilized in a variety of applications in power delivery systems. Because electric arcs, sparks or corona can decompose SF/sub 6/ into byproducts having chemical properties different from SF/sub 6/, environmental concerns arise regarding inadvertent human exposures to electrically-decomposed SF/sub 6/. Biological assays in our laboratory using mammalian cell culture systems have revealed that spark-decomposed SF/sub 6/ produces cell death, and the extent of cell killing increases with increasing spark energy. Chemical analysis of spark-decomposed SF/sub 6/ has identified the major decomposition pathways and byproducts, but biological testing of individual or byproduct mixtures has indicated that these major decomposition products do not contribute, in a significant fashion, to the cell lethality seen in our assays. Further experiments have suggested that S/sub 2/F/sub 10/ may be produced under our ...

Energy Technology Data Exchange (ETDEWEB)

Peroxisome proliferating agents (PPAs) are a structurally diverse group of chemicals that include environmental chemical contaminants such as certain chlorinated herbicides, solvents and plasticizers. PPAs have previously been shown to induce anti-trout laruci acid hydroxylase immunoreactive proteins in bluegill and catfish. In this investigation, induction of lauric acid hydroxylase activity and immunoreactive proteins was confirmed, and the mass spectral analysis of specific hydroxylation products was performed in order to identify possible species-specific differences in fatty acid metabolism. Male bluegill (Lepomis macrochirus) and channel catfish (Ictalurus punctatus) were administered clofibrate or ciprofibrate 48 hr prior to hepatic or trunk kidney (catfish only) microsome preparation. While no significant differences were observed in male catfish, male bluegill had significant decreases in hematocrit and plasma ...

Energy Technology Data Exchange (ETDEWEB)

Organic materials released from energy-related activities could affect human health and the environment. To better assess possible impacts, we developed a model to predict the fate of spills or discharges of pollutants into flowing or static bodies of fresh water. A computer code, Aquatic Pathways Model (APM), was written to implement the model. The computer programs use compartmental analysis to simulate aquatic ecosystems. The APM estimates the concentrations of chemicals in fish tissue, water and sediment, and is therefore useful for assessing exposure to humans through aquatic pathways. The APM will consider any aquatic pathway for which the user has transport data. Additionally, APM will estimate transport rates from physical and chemical properties of chemicals between several key compartments. The major pathways considered are biodegradation, fish and sediment uptake, photolysis, and evaporation. ...

Energy Technology Data Exchange (ETDEWEB)

N-substituted aromatics are important priority pollutants entering the environment primarily through anthropogenic activities associated associated with the industrial production of dyes, explosives, pestides, and pharmaceuticals. Anaerobic treatment of wastewaters discharged by these industries could potentially be problematical as a result of the high toxicity of N-substituted aromatics. The objective of this study was to examine the structure-toxicity relationship of N-substituted aromatic compounds to acetoclastic methanogenic bacteria. The toxicity was assayed to serum flasks by measuring methane production in granular sludge. Unacclimated cultures were used to minimize the biotransformation of the toxic organic chemicals during the test. The nature and the degree of the aromatic substitution were observed to have a profound effect on the toxicity of the test compound. Nitroaromatic compounds were, on the average, over 500-fold more toxic ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes research and development activities at the University of Regina, Saskatchewan, Canada on Optimization of CO{sub 2} Extraction Process Technologies. The ultimate goal of this research is to develop better and more effective CO{sub 2} separation processes which can be used to recover CO{sub 2} from industrial sources such as coal-fired power plants and coal gasification complexes at the lowest possible capital and operating costs. The research program has been supported by Saskatchewan Power Corporation, Saskatchewan Energy and Mines, Prairie Coal Ltd., the Canada Centre for Mineral and Energy Technology (CANMET), Fluor Daniel Inc. (USA), Sulzer Chemtech (Switzerland), Wascana Energy Inc., and Natural Sciences and Engineering Research Council of Canada (NSERC). Currently, six parallel and complementary projects have been carried out at the Process Systems Laboratory. These projects are: (1) Searching for new sterically hindered amines for high ...

Science.gov (United States)

The experimental work completed thus far in the areas of rapid radiochemical separations and metastable isomeric states is summarized. Activation analyses were made in samples of ore materials and metals using rapid radiochemical separations to isolate short-lived radioactive isotopes such as 3.77-min V/sup 52/ and 14.6-min Mo/sup 101/. The analytical results obtained were compared to the results obtained from standard chemical and instrumental analytical methods and, where possible, to activation analysis results obtained from longer-lived isotopes of the same element. Further work is in progress to improve the procedures, to evaluate the reproducibility and accuracy of the methods, and to evaluate their usefulness on a wide variety of sample matrices. The research on short-lived metastable isomers showed that 1.7-min W/sup 185m/ is not produced in sufficiently high yield for the development of a ...

Energy Technology Data Exchange (ETDEWEB)

Cross sections for some electro- and photoinduced spallation reactions on {sup 27}Al and {sup 51}V are measured in the energy region 130 MeV to 580 MeV with the activation method. Comparisons are made with calculations based on the Dalitz formalism for virtual photon spectra, and Monte Carlo calculations based on a cascade evaporation model, respectively. By use of Bremsstrahlung with end-point energies from threshold to 750 MeV, the yields for photo- production of{pi}{sup -}leading to ground and isomeric states in {sup 197}Hg are measured with the activation method. The activity from the Hg-isotopes were measured after a chemical separation of Hg from the target material. The yields and isomeric ratios are compared with impulse approximation calculations. For the photoproduction of {sup 195m}Hg and {sup 192}Hg from {sup 197}Au, the yields were measured. The experimental mean cross sections are compared ...

Science.gov (United States)

Several examples of agonist-directed trafficking of receptor signalling at 5-HT2A and 5-HT2C receptors have been reported that involve independent downstream transduction pathways. We now report the functional selectivity of a series of chemically diverse agonists at human (h)5-HT2A, h5-HT2B and h5-HT2C-VSV by examining two related responses, the upstream activation of Gq/11 proteins in comparison with its associated cascade of calcium mobilisation. At the h5-HT2A receptor, d-lysergic acid diethylamide (LSD) and the antiparkinsonian agents lisuride, bromocriptine and pergolide exhibit a higher potency for Gq/11 activation than calcium release in contrast with all the other tested ligands such as 5-HT, mCPP and BW723C86, that show an opposite preference of signalling pathway. Comparable observations are made at h5-HT2B and h5-HT2C-VSV receptors, suggesting a similar mechanism of functional selectivity for the three serotonin ...

Energy Technology Data Exchange (ETDEWEB)

Trihydroxynaphthalene reductase catalyzes two intermediate steps in the fungal melanin biosynthetic pathway. The enzyme, a typical short-chain dehydrogenase, is the biochemical target of three commercial fungicides. The fungicides bind preferentially to the NADPH form of the enzyme. Three X-ray structures of the Magnaporthe grisea enzyme complexed with NADPH and two commercial and one experimental fungicide were determined at 1.7 {angstrom} (pyroquilon), 2.0 {angstrom} (2,3-dihydro-4-nitro-1H-inden-1-one, 1), and 2.1 {angstrom} (phthalide) resolutions. The chemically distinct inhibitors occupy similar space within the enzyme's active site. The three inhibitors share hydrogen bonds with the side chain hydroxyls of Ser-164 and Tyr-178 via a carbonyl oxygen (pyroquilon and 1) or via a carbonyl oxygen and a ring oxygen (phthalide). Active site residues occupy similar positions among the three structures. A buried water ...

Energy Technology Data Exchange (ETDEWEB)

Photoelectrochemical oxidation is a potentially interesting method for destroying toxic organic materials. We have studied the photoelectrocatalytic activity of TiO{sub 2} films made by thermal oxidation of titanium, low pressure chemical vapour deposition (LPCVD), and anodisation of titanium. Two model organic compounds have been investigated for photooxidation: methyl phosphonic acid (MPA) which is a nerve gas analogue and 4-chlorophenol (4-CP) which is a chlorinated aromatic compound considered a standard for the evaluation of the TiO{sub 2} / UV processes. In addition to photoelectrochemical characterisation the films have been characterised by profilometry, XRD, AFM, photocurrent spectroscopy and Raman microscopy. Correlations have been made between the physical properties of the thin films and their catalytic activities. The most catalytic sample of thermally oxidised titanium was prepared at 400 deg C, and the ...

Energy Technology Data Exchange (ETDEWEB)

Six major use pesticides (Atrazine, Dicamba, Isoproturon, Lindane, Paraquat and Trifluralin) with differing physico-chemical properties were evaluated for the significance of 'bound' or non extractable residue formation. Investigations were carried out in purpose-built microcosms where mineralization, volatilisation, 'soil water' extractable and organic solvent extractable residues could be quantified. Extractable residues were defined as those accessible by sequential extraction where the solvent used became increasingly non-polar. Dichloromethane was the 'harshest' solvent used at the end of the sequential extraction procedure. {sup 14}C-labelled volatilised and {sup 14}CO{sub 2} fractions were trapped on exit from the microcosm. The pesticides were categorised into 3 classes based on their behaviour. (i) Type A (Atrazine, Lindane and Trifluralin) in which ring degradation was limited as was the formation of ...

International Nuclear Information System (INIS)

1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) is an anti-inflammatory agent with a propenone moiety and chemically synthesized recently. In this study, we examined the chemopreventive effect of FPP-3 on 7,12-dimethylbenz[a]anthracene (DMBA)-induced genotoxicity in MCF-7 cells. FPP-3 reduced the formation of the DMBA-DNA adduct. DMBA-induced CYP1A1 and CYP1B1 gene expression and enzyme activity were inhibited by FPP-3. It inhibited DMBA-induced aryl hydrocarbon receptor (AhR) transactivation and DMBA-inducible nuclear localization of the AhR. Induction of detoxifying phase II genes by chemopreventive agents represents a coordinated protective response against oxidative stress and neoplastic effects of carcinogens. Transcription factor NF-E2 related factor 2 (Nrf2) regulates antioxidant response element (ARE) of phase II detoxifying and antioxidant enzymes, such as glutathione S-transferase (GST) and NAD(P)H:quinone oxidoreductase (QR). FPP-3 ...

Science.gov (United States)

Pentaerythritol tetranitrate (PETN) is a relatively sensitive explosive used in many electroexplosive devices as well as in medicine. Of primary interest to LLNL is its use in items such as exploding bridgewire (EBW) detonators and exploding bridge foil initiators (EFI). In these devices the crystalline powder is pressed into a granular, low-density compact that can be initiated by an exploding wire or foil. The long-term stability of this pressed compact is of interest to weapon stockpile lifetime prediction studies. Key points about potential aging mechanisms can be summarized as follows: (1) There are a number of factors that can contribute to PETN instability. These include particle size, polymorphic phase transitions, crystal structure, impurities, moisture, occlusions, chemical incompatibility and biological (microorganism) action. of these factors the most important for long-term aging of high surface area powders used in detonators appears to be that of ...

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

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

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

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

Energy Technology Data Exchange (ETDEWEB)

The forest products industry is the third largest economic sector in Alberta, producing pulp and paper, dimensional lumber, paneling, and value added products, providing some 40,000 jobs . 'Value added' is a key component of expanding economic activity within the forest products sector. Wood residues can play a key role in obtaining more value from forest resources by providing new products, serving as feedstock to energy and chemical production, and playing a role in agriculture and land reclamation. One of the principal roles of the Forest Products Development Branch of the Alberta Economics Department is to encourage the development of the industry by creating new uses for these materials and developing awareness of the scope of the resource. Distances to markets, economic competition from conventional energy sources and coordination of research efforts are substantial barriers to further development that the Forest ...

Energy Technology Data Exchange (ETDEWEB)

High energy radiation was studied as a means for destroying hazardous organic chemical wastes. Tests were conducted at bench scale with a {sup 60}Co source, and at full scale (387 l/min) with a 1.5 MV electron beam source. Bench scale tests for both benzene and phenol included 32 permutations of water quality factors. For some water qualities, as much as 99.99% of benzene or 90% of phenol were removed by 775 krads of {sup 60}Co irradiation. Full scale testing for destruction of benzene in a simulated waste-water mix showed loss of 97% of benzene following an 800 krad dose and 88% following a 500 krad dose. At these loss rates, approximately 5 Mrad of electron beam irradiation is required to reduce concentrations from 100 g/l to drinking water quality (5 {mu}g/l). Since many waste streams are also inhabited by bacterial populations which may affect filtering operations, the effect of irradiation on those populations was also studied. {sup 60}Co and electron beam ...

Energy Technology Data Exchange (ETDEWEB)

Self-assembled monolayers (SAMs) on various metal, semiconductor or insulator substrates can be easily modified with specific functional groups of interest and have promising applications in surface wetting (hydrophobic/hydrophilic modification), tribology, corrosion protection, sensor electrodes modification, molecular and biomolecular recognition, protein adsorption, cell adhesion, and molecular- or organic-electronic device fabrications. In this paper, we highlight recent progress in the development of SAMs on solid substrates as well as their practical applications, with particular emphasis on the characterization of self-assembled aromatic thiol monolayers with different functional groups on Au(1 1 1) using synchrotron-based photoemission spectroscopy and near-edge X-ray absorption fine structure measurements. The SAM-related molecular orientation, electronic structures, and chemical bonding are presented. Using copper(II) phthalocyanine as a model system, we ...

Energy Technology Data Exchange (ETDEWEB)

Sandia National Laboratories has recently developed two major field test capabilities for unattended ground sensor systems at the Department of energy`s Nevada Test Site (NTS). The first capability utilizes the NTS large area, varied terrain, and intrasite communications systems for testing sensors for detecting and tracking vehicular traffic. Sensor and ground truth data can be collected at either of two secure control centers. This system also includes an automated ground truth capability that consists of differential Global Positioning Satellite (GPS) receivers on test vehicles and live TV coverage of critical road sections. Finally there is a high-speed, secure computer network link between the control centers and the Air Force`s Theater Air Command and Control Simulation Facility in Albuquerque NM. The second capability is Bunker 2-300. It is a facility for evaluating advanced sensor systems for monitoring activities in underground cut-and-cover facilities. ...

International Nuclear Information System (INIS)

Low-temperature #gamma# radiolysis and photolysis of crystalline 2,4,6-triazido-3,5-dichloropyridine (TAP) were studied by means of the ESR technique. It was found that the long-term irradiation of TAP at 77 K leads to the appearance of characteristic signals of quintet 2,6-dinitreno-4-azido-3,5-dichloropyridine and 2,4-dinitreno-6-azido-3,5-dichloropyridine; the radiation-chemical yield was 0.035 and 0.012 molecule/100 eV, respectively. The photolysis of crystalline 2,4,6-triazido-3,5-dichloropyridine proceeded less effectively, producing only quintet 2,6 dinitrene with a quantum yield of #approx#4.5 x 10"-"4. The study showed that the generation of high-spin nitrenes via radiolysis of crystalline azides is much superior to the photochemical technique in efficiency and may be of practical importance for the preparation of magnetically active organic materials

International Nuclear Information System (INIS)

In this thesis the rate constants for a number of radical reactions in aqueous solution have been studied in a wide temperature range. The reactions of H with H_2O_2, OH and HO_2 and the reactions of HO_2 with OH, Fe"2"+ and Cu"2"+ have been studied. For each reaction rate constants have been determined as a function of temperature using the technique of high temperature, high pressure (HTP) pulse radiolysis. The rate constants were obtained by fitting a kinetic computer model to the experimental data. From an Arrhenius plot the activation energy of each reaction was determined. The data determined in this way are important for modeling of radiolysis in nuclear light water reactors. A previously developed model for calculation of the effect of water radiolysis products on oxidation and dissolution of spent nuclear fuel has been improved. In the new model, called TraRaMo, simultaneous transport by diffusion and chemical reactions induced by ...

International Nuclear Information System (INIS)

A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical NO-detector at variable gas ...

Energy Technology Data Exchange (ETDEWEB)

Stearic acid (C{sub 1}8H{sub 36}O{sub 2}) was treated into Ar and Ar-O{sub 2}(10%) pulsed DC discharge created by a cathode-anode confined system. The samples were placed at the floating potential. The results show that the mass variation of the stearic acid samples after Ar-O{sub 2} plasma exposure is more important than the pure Ar plasma treatments. This comportment demonstrate that the oxygen actives species (O and O{sub 2} in all states) strongly enhance the etching process with regards to A{sup *} species, regardless of their concentration. After treatment by Ar and Ar-O{sub 2} plasma, analyses by X-ray diffraction show a significant structural modification of the samples surface, utilizing Ar-O{sub 2} plasma the modification was more pronounced. The chemical composition evolution shows that the acid function is etched preferentially in the beginning of the treatment (about 5 min) and that after 10 min the carbonic chains seems to be ...

International Nuclear Information System (INIS)

During the phases of separation, treatment, conditioning and storage of radioactive waste, destructive and nondestructive methods for their characterization are needed. In order to satisfy this necessity, in the frame of the National Program of Research and Development, the 'Laboratory for characterization of spent nuclear fuel and high/medium level radioactive waste- LABORAD' was created. The purpose of the project was to accredit the analysis methods available in the laboratory, and also to develop new methods for the characterization of the radioactive waste. A special attention was paid to the high-level radioactive waste and spent nuclear fuel characterization that require special facilities for handling. These facilities (e.g. hot cells, remote handlers, transport container) are already available in our institute. Experimental results and performances obtained during validation of the methods are presented in this paper. The laboratory (LABORAD) is notified as testing laboratory ...

International Nuclear Information System (INIS)

SiC has been considered as a primary candidate material for a first wall component in future fusion reactor because it has been claimed that SiC has excellent high-temperature properties, good chemical stability and low activation. However, the behavior of tritium on SiC has not been discussed yet. In this study, tritium trapping capacity on the surface of SiC was experimentally obtained at the temperature range of 25-800 deg. C in consideration of tritium trapping to the experimental system. The capacity, which was independent of the water vapor pressure in the gas phase and the temperature, was determined as about 10"6 Bq/cm"2. The isotope exchange reaction rate between tritiated water in a gas phase and hydrogen on the surface was quantified at the temperature of 25, 500 and 700 deg. C in consideration of the behavior of tritium trapping at change of experimental condition by the numerical curve fitting method applying the serial reactor ...

International Nuclear Information System (INIS)

Full text: The excessive use of chemical pesticides to control agricultural pests is becoming alarming. The objective of this study is to search for biopesticides of plant origin that could be used to control one of the major pest of fruit production; the Mediterranean fruit fly (Ceratitis capitata Wied.). A colony of the Lebanese wild strain of this insect was reared under laboratory condition to provide biological material. The insecticidal activity of the essential oils extracted from aromatic plants in Lebanon was assessed. The tested plants are: Foeniculum vulgare, Thymbra spicata, Artemisia herba alba, Origanum syriacum, Ruta chalepensis, Lavandula stoechas, Salvia fruticosa, Mentha microphylla, Juniperus oxycedrus, Rosmarinus officinalis, Myrtus communis, Laurus nobilis and Ocimum gratissimum. Results show that essential oils isolated from F. vulgare, T. spicata, A. herba alba, O. syriacum and R. chalepensis have promising insecticidal ...

International Nuclear Information System (INIS)

The properties of the mass-metallicity relation among dwarf spheroidal galaxies are discussed in terms of a model which assumes that the internal chemical evolution of the dwarf spheroidals was promoted by supernova activity. The model can be used to explain the observed dwarf spheroidal mass-metallicity relation assuming the present mass of these systems M sub s is proportional to their initial masses M as M sub s varies according to a power-law index of exp 7/4. It is inferred from the power-law dependence of M on the proto-cloud radius that the most massive dwarf spheroids were formed from the densest clouds. The observed slope of the mass-metallicity relation for dwarf spheroidal galaxies is found to be significantly different from theoretical estimates of this slope for elliptical galaxies. It is suggested that the difference may imply that spheroidal dwarfs and elliptical galaxies had different formation histories, confirming Kormendy's ...

International Nuclear Information System (INIS)

The objective this work was to evaluate the gamma radiation processing for elimination of organic contaminants on industrial wastewater. Standard samples with 17 hydrocarbons (acetophenone, anisole, benzene, chlorobenzene, cyclohexanone, N, N-dimethylaniline, phenol, naphtalene, 1-chloronaphtalene, n-octadecane, p-nitrotoluene, toluene, tetrachloroethane, tetramethylbenzene, n-undecane, m-xylene and o-xylene) was preparated in hexane with total concentration of 1 #mu# g/ #mu# l which was analyzed by gas chromatography. Other sample with the same concentration of these hydrocarbons in acetone was used to contaminate water samples, which were irradiated with gamma radiation from Co-60 between doses 5.0 to 20.0 KGy and dose rate of 1.162 KGy/h. The activity of source was 1470 Ci. Percents destruction of hydrocarbons were: 79.76 % to 5.0 KGy, 85.97 % to 7.5 KGy, 86.24 % to 10.0 KGy, 86.72 % to 12.5 KGy, 88.92 % to 15.0 KGy, 91.74 % to 17.5 KGy and 92.38 % to 20.0 KGy. ...

Energy Technology Data Exchange (ETDEWEB)

Lubricant additives have been known to affect rolling element bearing surface durability for many years. Tapered roller bearings were used in fatigue testing of lubricants formulated with gear oil type additive systems. These systems have sulfur- and phosphoruscontaining compounds used for gear protection as well as bearing lubrication. Several variations of a commercially available base additive formulation were tested having modified sulfur components. The variations represent a range of ''active'' extreme pressure (EP) chemistries. The bearing fatigue test results were compared with respect to EP formulation and test conditions. Inner ring near-surface material in selected test bearings was evaluated on two scales: the micrometer scale using optical metallography and the nanometer scale using transmission electron microscopy (TEM). Focused-ion beam (FIB) techniques were used for TEM specimen preparation. Imaging and ...

Energy Technology Data Exchange (ETDEWEB)

In the wide range from brown coal to anthracite, an investigation was made of effects of heat treatment on physical/chemical properties and of coal rank dependence. For the experiment, 12 kinds of coal samples were used, and for heat treatment, the fluidized bed heated by the electric furnace and the infrared-ray gold image furnace were used. To examine characteristics of the heat-treated coal char, conducted were oxygen gasification, TPD measurement, XRD measurement, alkali metal measurement, and pore distribution measurement. The following were obtained from the experiment. The gasification reaction rate of the char heat-treated in the temperature range between 900{degree}C to 1700{degree}C decreases with a rise of the temperature of heat treatment, and the degree of decrease in the rate depends on coal rank. The order of gasification rate between coal ranks depends on the temperature of heat treatment, and the lower the heat treatment temperature is, the more ...

International Nuclear Information System (INIS)

Full text: The production of #beta#-sialon from kaolinite and carbon has been studied using Hulu Langat Kaolin and activated carbon as raw materials. The sintered temperature is shown to play a prominent role in the process of sialon conversion. Apart from temperature, nitrogen flow rate is also affect the production of #beta#--sialon. This study was carried out on the effect of additive, Y_2O_3 and Al_2O_3 at different temperature that will be mixed and sintered. The additives are expected to affect the formation of #beta#--sialon and Y-sialon upon the synthesis. The mineral and phase development was analysed using X-Ray Diffraction technique (Rigaku Geigerflex) while its chemical compositions through X-Ray Fluorescent Spectrophotometer (Shimadzu XRF 1700) and the particle size distribution analysis through Particle Size Analyser (Horiba, CAPA 700). The observed changes in the microstructure were analysed using the Hitachi S2500 Scanning ...

Energy Technology Data Exchange (ETDEWEB)

A survey to assess the techniques used to control occupational exposure to formaldehyde (50000) and methanol (67561) was conducted at the E. I. DuPont de Nemours and Company (SIC-2869) formaldehyde production unit, Linden, New Jersey, in October 1982. Exposure concentrations were reduced primarily by the use of a process that was completely enclosed except for process sampling, methanol unloading, and formaldehyde discharge points. Local and area exhaust ventilation, and work practices were also used to control exposures. Formaldehyde concentrations in the absorber area were controlled by burning the exit gases in an afterburner and discharging them high above the ground. Analysis of area and breathing zone samples showed methanol and formaldehyde concentrations below the OSHA limits of 200 and 3 parts per million, respectively. The authors conclude that workers are not overexposed to either methanol or formaldehyde on a short or long term basis. Maintenance workers should not be ...

International Nuclear Information System (INIS)

This book deals with organizations that operate in high hazard industries, such as the nuclear power, aviation, oil and chemical industry organisations. The society puts a great strain on these organisations to rigorously manage the risks inherent in the technology they use and the products they produce. In this book, an organisational psychology view is taken to analyse what are the typical challenges of daily work in these environments. The analysis is based on a literature review about human and organisational factors in safety critical industries, and on the interviews of Finnish safety experts and safety managers from four different companies. In addition to this, personnel interviews conducted in the Finnish nuclear power plants are utilised. The authors come up with eight themes that seem to be common organizational challenges cross the industries. These include e.g. how does the personnel understand the risks and what is the right level for rules and ...

Energy Technology Data Exchange (ETDEWEB)

This report presented an analysis of incidents gathered by the Canadian upstream oil and gas industry committee in relation to explosive atmospheres in wellbores, vessels, tanks, and piping systems. The aim of the report was to develop industry recommended practices for oil and gas industry fires and explosions. Two accident theory models were used to set out the relationships between hazards, defenses, and losses. Three levels of defenses were identified based on organizational, local workplace, and human factors. An organizational responsibility approach was used to examine the activities of key people with the system. Incidents were analyzed based on an expanded fire triangle used to identify fire and explosion hazards. The study showed that the ignition of hydrocarbons into the air was a factor in nearly 50 per cent of the incidents. A lack of understanding of liquid-hydrocarbon properties was demonstrated in incidents involving oxidized hydrocarbons. A lack of ...

Energy Technology Data Exchange (ETDEWEB)

This project was supported through ERDA to demonstrate that the temporal distribution of tritium can be documented by the analysis of bound hydrogen in annual tree-ring samples. The project focuses on two sample locations at the Savannah River Site (SRS), a nuclear material production facility located in Aiken, SC. The SRS provided samples of cross-sections from a single tree that were to be pooled together for analysis. Annual tree-rings were identified in each cross-section sample and separated for the period 1954 to 1993. These annual samples were ground and chemically treated to separate the hollocellulose fraction of the wood, then subsequently combusted and the resulting water counting using low-level liquid scintillation counting equipment. Additionally, the ground annual tree-rings were gamma-counted to determine any temporal variation in radionuclide activity and analyzed with x-ray fluorescence to find any temporal variation in ...

Energy Technology Data Exchange (ETDEWEB)

The symmetrical complexes [{sup 99m}Tc][TcN(R{sub 2}PS{sub 2}){sub 2}] [R = CH{sub 3}, CH{sub 2}CH{sub 3}, CH{sub 2}CH{sub 2}CH{sub 3}, CH{sub 2}(CH{sub 3}){sub 2}], and the unsymmetrical complex [{sup 99m}Tc][TcN(Me{sub 2}PS{sub 2})(Et{sub 2}PS{sub 2})] have been prepared, at tracer level, through a two-step procedure involving the preliminary formation of a prereduced technetium nitrido intermediate followed by substitution reaction onto this species by the appropriate dithiophosphinate ligand [R{sub 2}PS{sub 2}]Na. The chemical identity of the resulting complexes have been established by comparison with the corresponding {sup 99}Tc-analogs prepared, at macroscopic level, by reacting the complex [{sup 99}TcNCl{sub 4}] [n-Bu{sub 4}N] (n-Bu = n-butyl) with an excess of ligand in methanol, and characterized by elemental analyses and spectroscopic techniques. The complexes are neutral and lipophilic, and possess a square pyramidal geometry, with an apical Tc N group ...

Energy Technology Data Exchange (ETDEWEB)

Manganese is an essential metal of toxicologic concern primarily because of exposure via inhalation. Environmental forms of Mn exist mainly as insoluble oxides, yet much of the research information available relates to the soluble salts. In the present study, adult male Sprague-Dawley rats were intratracheally instilled with either soluble MnCl/sub 2/ or insoluble Mn/sub 3/O/sub 4/ labeled with /sup 54/Mn. Lungs and other major organs were sampled over a span of 3 mo after dosing with the respective chemicals, which were equivalent to 8 ..mu..Ci and 1 ..mu..mol of manganese in 0.2 ml of buffer. There was rapid clearance of Mn from the lungs in the case of both chemicals; the chloride cleared at an initial rate of nearly four times that of the oxide. Despite this early difference, the amount of /sup 54/Mn remaining in the lungs after 2 wk was similar for both compounds. The level of /sup 54/Mn in the liver, kidney, spleen, and testes peaked at ...

Energy Technology Data Exchange (ETDEWEB)

Before low-level waste may be disposed of, a performance assessment must be written and then approved by the DOE (DOE 1988a DOE 1999a). The performance assessment is to determine whether ''reasonable assurance'' exists that the performance objectives of the disposal facility will be met. The DOE requirements for waste disposal (DOE 1988a DOE 1999a) require the protection of public health and safety; and the protection of the environment. Although quantitative limits are sometimes stated (for example, the all-pathways exposure limit is 25 mrem/year), usually the requirements are stated in a general nature. Quantitative limits were established by: investigating all potentially applicable regulations as well as interpretations of the review panels which DOE has established to review performance assessments, interacting with program management to establish the additional requirements of the program, and interacting with the public (i.e., the Hanford ...

International Nuclear Information System (INIS)

The study of tropospheric kinetics underlies global change because key greenhouse gases are photochemically active. Modeling of tropospheric chemistry on a global scale is essential because some indirect greenhouse gases are short-lived and interact in a non-linear fashion. It is also extremely challenging, however; the global change grid is extensive in both the physical and temporal domains, and critical lower atmospheric species include the organics and their oxidized derivatives, which are numerous. Several types of optimization may be incorporated into kinetics modules to enhance their ability to simulate the complete lower atmospheric gas phase chemical system. (1) The photochemical integrator can be accelerated by avoiding matrix and iterative solutions and by establishing families. Accuracy and mass conservation are sacrificed in the absence of iteration, but atom balancing is restorable post hoc. (2) Chemistry can be arranged upon the ...

International Nuclear Information System (INIS)

Changes in physical and chemical characteristics of aquatic habitats made to reduce or eliminate ecological risks can sometimes have unforeseen consequences. Environmental management activities on the U.S. Dept. of Energy reservation in Oak Ridge, Tennessee,have succeeded in improving water quality in streams impacted by discharges fi-om industrial facilities and waste disposal sites. The diversity and abundance of pollution-sensitive components of the benthic macroinvertebrate communities of three streams improved after new waste treatment systems or remedial actions reduced inputs of various toxic chemicals. Two of the streams were known to be mercury-contaminated from historical spills and waste disposal practices. Waterborne mercury concentrations in the third were typical of uncontaminated systems. In each case, concentrations of mercury in fish, or the apparent biological availability of mercury increased over the ...