Energy Technology Data Exchange (ETDEWEB)

We tested the hypothesis that insulin-dependent diabetic patients with coronary artery bypass graft surgery experience altered coupling of cerebral blood flow and oxygen consumption. In a study of 23 patients (11 diabetics and 12 age-matched controls), cerebral blood flow was measured using 133Xe clearance during nonpulsatile, alpha-stat blood gas managed cardiopulmonary bypass at the conditions of hypothermia and normothermia. In diabetic patients, the cerebral blood flow at 26.6 +/- 2.42 degrees C was 25.3 +/- 14.34 ml/100 g/min and at 36.9 +/- 0.58 degrees C it was 27.3 +/- 7.40 ml/100 g/min (p = NS). The control patients increased cerebral blood flow from 20.7 +/- 6.78 ml/100 g/min at 28.4 +/- 2.81 degrees C to 37.6 +/- 8.81 ml/100 g/min at 36.5 +/- 0.45 degrees C (p less than or equal to 0.005). The oxygen consumption was calculated from jugular bulb effluent and increased from hypothermic values of 0.52 +/- 0.20 ...

International Nuclear Information System (INIS)

The extraction-spectrophotometric method has been used to study lanthanoid ion complexing (Pr, Nd, Ho and Er) with antipyrine (Ant) and salicylic acid (Sal). The component relationship in different-ligand compounds Ln:Aut:Sal=2:3:6 and solvate number equal to 5 are determined; molar extinction coefficients of binary and different-ligand compounds are calculated. Oscillator strengths of absorption bands corresponding to supersensitive transitions of neodymium, holmium, erbium and some most intensive praseodymium bands are calculated. The study of IR spectra of investigated compounds allows to conclude on formation of coordination bonds of the central atom with the antipyrine molecule through the oxygen of the carbonyl group as well as on carboxyl group hydrogen substitution for metal and formation of coordination bond with OH group in salicylic acid molecules.

Energy Technology Data Exchange (ETDEWEB)

General conclusions, principles and order of substantiating the extractable reserves and coefficients of oil extraction from oil and oil and gas fields are presented. Recommendations are made for solving questions of constructing calculation models for heterogeneous beds, schematization of the working conditions, selection of mathematical models for oil extraction for different geological-field conditions and different stages of ''life'' of the field.

International Nuclear Information System (INIS)

The Monte Carlo transport codes LAHET and MCNP were used to calculate energy fluence spectra at three neutron therapy facilities. The results compare very favourably with measured data. Kerma spectra and the ratio of ICRU muscle tissue kerma to A-150 kerma, along the carbon to oxygen kerma ratio, were determined. Absorbed dose rate calculations are in reasonable agreement with measured values. Use of these codes to study modifications to existing therapy beams is briefly discussed. (author).

Energy Technology Data Exchange (ETDEWEB)

For each sample, one 30-gallon drum containing approximately 90 lb of coal at {minus}1/4 inch was designated for headspace oxygen analysis and coal quality monitoring at yearly intervals. Headspace oxygen analysis and retrieval of a 5-lb sample for coal analysis have begun. Headspace oxygen contents are shown in Table 1. Preparation and analysis of these samples for the second yearly quality evaluation is in progress. We have initiated a study of different means of storage in preventing sample deterioration and in maintaining an inert headspace atmosphere. The work was performed with support from the Penn State Cooperative Program in Coal Research. A run-of-mine sample of medium-volatile bituminous Lower Kittanning coal was collected as PSOC-1536 and promptly processed. Gieseler fluidity FSI, alkali extraction and preparation of petrographic pellets were accomplished within 32 hours of ...

British Library Electronic Table of Contents (United Kingdom)

Previously, we demonstrated that the lithium ion conduction in the perovskite-type manganese fluoride is attributed to counter cation-site vacancy mechanism. The divalent counter cation-doped KxBa(1-x)/2MnF3 was theoretically predicted as the lithium ion conductor in the perovskite-type manganese fluoride. In this study, we considered the oxygen doping for KxBa(1-x)/2MnF3 to realize the higher lithium ion conductivity. It is because lithium ion forms the stronger ionic bond with the doped oxygen anion. The hybrid-DFT calculations were performed to investigate the lithium ion conduction in the oxygen-doped KxBa(1-x)/2MnF3. The calculation results were discussed from the viewpoints of the potential energy curve, electron densities, and charge and spin densities. The effect of the lithium ion...

Energy Technology Data Exchange (ETDEWEB)

An oxidative method for enriching the content of humic acids in a mined lignite from Umbria (central Italy) is described. A mild oxidation using H{sub 2}O{sub 2} in an alkaline medium was successful in increasing the percentage of lignite-derived humidifed carbon from 5.77% to 33.67%. The newly formed humic acids showed a higher number of oxygen-bearing functional groups, a lower carbon/oxygen ratio and a higher absorbance ratio at 465 and 665 nm (E{sub 4}/E{sub 6}) in diluted solution compared to the native lignite-derived humic acids. A high E{sub 4}/E{sub 6} ratio indicated less condensation of the aromatic nucleus and a lower molecular weight in comparison to the lignite-derived native humic acids.

British Library Electronic Table of Contents (United Kingdom)

Nanocrystalline chromium oxynitride films were deposited by reactive RF magnetron sputtering of metallic chromium target in argon and helium atmospheres. The paper deals with consequence of increase in oxygen partial pressure on structural, hydrophobic and optical properties of chromium oxynitride films. The film stoichiometry changes from CrN and Cr2O3 to only Cr2O3 with increase in oxygen partial pressure as evident from X-Ray Diffraction analysis in both cases. The average crystallite size decreases with increase in oxygen partial pressure for both gas atmospheres. The thickness calculated from transmission data and surface profilometer are in good harmony with each other. The deposited films are hydrophobic by nature and the contact angle of the films varies as a function of surface ro...

International Nuclear Information System (INIS)

In this study, the degrees of destruction of hemoglobin irradiated in atmospheres of air and argon were compared. Hemoglobin preparations were irradiated in the forms: oxyhemoglobin (HbO_2) deoxyhemoglobin (Hb"2"+) and methemoglobin (MetHb) applying doses of 0.5 to 5 Mrad. The degree of hemoglobin destruction was estimate on the basis of changes in the values of the absorption coefficient at the Soret band, the absorption ratio A_5_0_5/A_5_6_3 determined after conversion of irradiated preparations into MetHb, absorption coefficinets for pyridine hemochromogen obtained from irradiated preparations, and changes in parameters characterizing the hemoglobin oxygenation reaction (log p/sub 1/2/O_2 and the Hill n coefficient). The calculated oxygen enhancement ratios S were generally higher than 1 for the parameters estimated. This indicates that the presence of oxygen during irradiation enhances hemoglobin ...

CERN Document Server

In the 21st century, Aerial and satellite images are information rich. They are also complex to analyze. For GIS systems, many features require fast and reliable extraction of open space area from high resolution satellite imagery. In this paper we will study efficient and reliable automatic extraction algorithm to find out the open space area from the high resolution urban satellite imagery. This automatic extraction algorithm uses some filters and segmentations and grouping is applying on satellite images. And the result images may use to calculate the total available open space area and the built up area. It may also use to compare the difference between present and past open space area using historical urban satellite images of that same projection

International Nuclear Information System (INIS)

Hydrogen (H) plasma treatment, oxygen (O) plasma treatment and water (H_2O)-vapor heat treatment for polycrystalline-silicon (poly-Si) thin-film transistors (TFTs) have been analyzed by separately extracting trap density at a front silicon-oxide interface (D_F) and trap density at a back interface (D_B). It is found that the H plasma treatment is apt to generate D_F and D_B. The O plasma treatment reduces D_F, while the H_2O-vapor heat treatment reduces both D_F and D_B. Improvement of transistor characteristics of poly-Si TFTs depends on understanding these results.

Energy Technology Data Exchange (ETDEWEB)

The experimental maturation of an immature kerogen from the Toarcian of the Paris basin has been carried out in a confined system under pressure. The evolution of various thermal maturity parameters was plotted against the corrected organic carbon percentage chosen as a common maturity indicator and compared with data extracted from a natural series. Results show the occurrence of three distinct stages respectively characterized by the removal of oxygenated compounds, the genesis of liquid hydrocarbons and the production of gaseous hydrocarbons.

Energy Technology Data Exchange (ETDEWEB)

Because of its high energy density, compatibility with aqueous electrolytes and the low toxicity of its active materials, the zinc-air battery system is an interesting candidate for electric vehicle applications. The use of O{sub 2} from the air as a reactant requires a partially open cell construction and a technologically challenging air interface. This report describes the research and development program at the Paul Scherrer Institute which finally led to the demonstration of a durable, electrically rechargeable zinc-oxygen battery. In a first phase the research program was focused on the development of bifunctional oxygen diffusion electrodes and pasted zinc electrodes. The current-potential behaviour and the cycle life performance of anodes and cathodes was tested in single electrode measurements (three-electrode arrangements) as well as in complete monopolar zinc-oxygen and zinc-air cells. La{sub 0.6}Ca{sub ...

International Nuclear Information System (INIS)

The wavefunction of a positron in ReO is calculated using the augmented-plane-wave method. Due to the loosely-packed structure of ReO_3, the ground-state GAMMA_1 wavefunction exhibits a marked anisotropy particularly around the oxygen ions, and a large fraction of a positron is distributed in the interstitial region. Experimental results of the positron annihilation 2#gamma#-correlations and the positron annihilation rates in ReO_3 are discussed based on the positron wavefunction. (orig.).

Scientific Electronic Library Online (English)

Abstract in english A mathematical model has been developed for describing the dynamic operation of the N-formylmorpholine extractive distillation column and the corresponding solvent recovery column in the benzene extraction plant. The NRTL equation was used to calculate the equilibrium and thermodynamic properties of the mixtures. The validity of the model in terms of temperature, pressure and split fraction was examined using actual plant data at steady-state conditions. Comparison betwee (more) n model results and plant data shows good consistency. In order to improve the control of the process and selection of the optimal control strategy, the model was used to find the optimum values of the constants of the controllers with Nelder-Mead algorithm during unsteady-state operation by minimizing the deviation from steady-state conditions. The outcome of this study could be used by operators and engineers to increase the ...

Science.gov (United States)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

Due to a leakage from a 12-inch pressurized diesel steel pipe four years ago, an area of approximately 30,000 square meters was contaminated. A pilot study applying the technology of in-situ enhanced bioremediation was conducted. In the study, a field test kit and on-site monitoring equipment were applied for site characterization and treatment verification. Physically, the enhanced bioremediation study consisted of an air extraction and air supply system, and a nutrition supply network. Certain consistent sampling methodology was employed. Progress was verified by daily monitoring and monthly verification. The objective of this study was to evaluate the capabilities of indigenous microorganisms to biodegrade the petroleum hydrocarbons with provision of oxygen and nutrients. Nine extraction wells and eight air sparging wells were installed. The air sparging wells injected the air into geoformation and the ...

British Library Electronic Table of Contents (United Kingdom)

Absorption coefficient data are presented for molecular oxygen at temperatures between 1100 and 2000K and discrete wavelengths between 211 and 235nm. Measurements were made behind reflected shock waves using broad-linewidth ultraviolet laser radiation generated from a frequency-quadrupled, tunable, pulsed Ti:Sapphire laser. Test mixtures consisting of 15% O"2, 15% He and balance Ar were used to minimize the influence of vibrational relaxation on the reflected shock temperature. The experimental results are in good agreement with theoretical calculations and confirm that discrete features from the Schumann-Runge system dominate between 211 and 235nm at temperatures higher than 1100K.

International Science & Technology Center (ISTC)

Development of Oxygen Ion-Implanted Collector materials for Thermal Emission Converters of Thermal Energy into the Electric One.

Energy Technology Data Exchange (ETDEWEB)

The potential to scrub biogas in a high rate pond (HRP) was evaluated using apparatus designed to maximize gas-liquid contact. Experiments compared the removal of carbon dioxide from synthetic biogas by an 'in-pond angled gutter' to that by a simulated 'counter-current pit'. Results showed that the counter current pit has potential for use in biogas scrubbing, with synthetic biogas carbon dioxide composition consistently reduced from 40% to<5%. The in-pond angled gutter was less effective due to bubble coalescence which reduced the total bubble surface surface area available for gas transfer. Measurement of oxygen levels in the scrubbed biogas showed that despite supersaturation of oxygen in the HRP water, there was little transfer to the biogas, so that explosive methane/oxygen mixtures would not be formed. Theoretical calculations indicated that the amount of ...

Science.gov (United States)

A finite three-dimensional layer-by-layer photonic crystal with planar defects in a layer is shown to drastically modify the spontaneous emission rate of an embedded dipole. Finite-difference time-domain calculations with one quarter symmetric boundary condition and perfectly matched layer demonstrate the strong enhancement effects induced by the cavity resonance of defect modes and band-edge resonant modes. Simulation shows that the emission spectra are quite different when the position or polarization of the dipole is changed. Moreover, the extraction efficiency is calculated to observe the percentage of light leakage through a substrate.

International Nuclear Information System (INIS)

We measured differential cross sections and vector analyzing powers for the "4"8Ca(d,n)"4"9Sc reaction at 79 MeV. An overall energy resolution of about 325 keV was achieved, and data were extracted for states up to 3.4 MeV of excitation. Both distorted-wave Born approximation and Johnson-Soper adiabatic approximation calculations were performed; in general, the Johnson-Soper adiabatic approximation calculations provide a better description of the data, and yield reasonable spectroscopic factors.

International Nuclear Information System (INIS)

We have measured the transverse asymmetry A_T_"' in the quasielastic "3He-vector(e-vector,e"') process with high precision at Q"2 values from 0.1 to 0.6 (GeV/c)"2. The neutron magnetic form factor G_M"n was extracted at Q"2 values of 0.1 and 0.2 (GeV/c)"2 using a nonrelativistic Faddeev calculation which includes both final-state interactions (FSI) and meson-exchange currents (MEC). Theoretical uncertainties due to the FSI and MEC effects were constrained with a precision measurement of the spin-dependent asymmetry in the threshold region of "3He-vector(e-vector,e"'). We also extracted the neutron magnetic form factor G_M"n at Q"2 values of 0.3 to 0.6 (GeV/c)"2 based on plane wave impulse approximation calculations.

Science.gov (United States)

A 65-yr-old female developed cough, fever and dyspnoea following repeated exposure to a home ultrasonic humidifier. High-resolution computed tomography showed ground-glass opacity in both lung fields. Arterial blood gas analysis gave an oxygen tension of 8.38 kPa (63 Torr). Pulmonary function testing revealed restrictive ventilatory impairment with a reduction in the diffusing capacity. The diagnosis of extrinsic allergic alveolitis (EAA) was confirmed by radiographic findings, pathological evidence of alveolitis and reproductive development by a provocation test to the humidifier water. The yeast Debaryomyces Hansenii was the only microorganism cultured from the water of the humidifier. The double diffusion precipitating test and lymphocyte proliferative response was positive for an extract of D. Hansenii, providing evidence to incriminate this fungus. This is the first described case of EAA caused by D. Hansenii. PMID:12449192

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.

Science.gov (United States)

We examine the electric and magnetic strange form factors of the nucleon in the pseudoscalar-vector SU(3) Skyrme model, with special emphasis on the effects of isospin symmetry breaking (ISB). It is found that ISB has a nontrivial effect on the strange vector form factors of the nucleon and its contribution to the nucleon strangeness is significantly larger than one might naively expect. Our calculations and discussions may be of some significance for the experimental extraction of the authentic strangeness.

International Nuclear Information System (INIS)

Separate entries were made in the data base for 17 of the 19 papers included. Two papers were previously included in the data base. Workshop reports are included on (1) nuclear level density theories and nuclear model reaction cross-section calculations and (2) extraction of nuclear level density information from experimental data.

Energy Technology Data Exchange (ETDEWEB)

The contribution of pulsar accelerated nuclei to the cosmic rays inside the Galaxy is calculated assuming that a significant part of the pulsar rotational energy is lost on acceleration of iron nuclei extracted from the surface of the neutron star. Different models of the galactic pulsar population are discussed. It is shown that the best description of the observed cosmic ray spectrum and the mass composition between a few 10{sup 15} eV and a few 10{sup 18} eV is obtained for the model B of Lorimer et al. (1993)

Energy Technology Data Exchange (ETDEWEB)

Non-invasive methods are described for estimating local cerebal blood flows (LCBF) and local partition coefficients (Llambda) during inhalation of 30 % stable xenon gas (Xe) in oxygen during CT scanning. After the denitrogenation with pure oxygen breathing, 30 % Xe is inhaled for four minutes to minimize subanesthetic effects with a rubber facemask and the delivery system of Xe. Local time-..delta.. Hounsfield units curve during the Xe wash-in and wash-out phase is utilized in order to calculate Llambda and LCBF using a least squares curve fitting analysis. Calculated Llambda and LCBF with the new method manifested reasonable distribution between the grey and white matters, and reproducibility was excellent in our study. Several case studies of patients with cerebral infarction are presented to demonstrate the characterization of Llambda and LCBF patterns in various tissues and theoretical grounds ...

International Nuclear Information System (INIS)

The effect of variations of the fundamental constants on the thermonuclear rate of the triple alpha reaction, "4He(#alpha##alpha#, #gamma#)"1"2C, that bridges the gap between "4He and "1"2C is investigated. We have followed the evolution of 15 and 60 M#centre dot# zero metallicity stellar models, up to the end of core helium burning. They are assumed to be representative of the first (Population III) stars. The calculated oxygen carbon abundances resulting from helium burning can then be used to constrain the variation of the fundamental constants.

International Nuclear Information System (INIS)

Scandium reacts with 4-(2-pyridylazo)resorcinol in the presence of monocarboxylic acids (X) to form mixed-ligand complexes with a Sc:PAR:x ratio of 1:2:2. The chemical nature of this interaction has been established, and the extraction of these mixed-ligand complexes has also been investigated; stability constants and molar extinction coefficients have been calculated. The values of the latter decrease in the order CH_3COOH > CH_2ClCOOH > CCl_3COOH. The formation and extraction of mixed-ligand complexes in Sc-PAR-HX systems make it possible to increase the sensitivity and selectivity of scandium determination in comparison with the use of the Sc-PAR mono-ligand complex.

Energy Technology Data Exchange (ETDEWEB)

By ab-initio calculation we show that the (Ga,Fe)N ground state may be changed from anti-ferromagnetic to ferromagnetic by acceptor defect like Ga vacancies. The electronic structures are calculated by using the Korringa-Kohn-Rostoker (KKR) method combined with coherent potential approximation (CPA). We show that we can increase the magnetic moment of Fe in p-type GaN by oxygen co-doping. Mechanism of exchange interactions between magnetic ions in p-type (Ga,Fe)N is also studied. The effect of external magnetic field on the electronic structure of (Ga, Fe)N and p-type (Ga, Fe)N is investigated.

Energy Technology Data Exchange (ETDEWEB)

Abstract not provided

Energy Technology Data Exchange (ETDEWEB)

The interdependence of thermodynamic parameters, phase equilibria, and electrochemical measurements can be used as a powerful tool in the development of high specific energy cells. These principles were used in the analysis of electrochemical experiments performed on ternary lithium-transition metal-oxide (M = Mn, Fe, and Co) positive electrodes. The free energies of formation of LiMnO/sub 2/, Li/sub 5/FeO/sub 4/, LiFeO/sub 2/, and LiCoO/sub 2/ were found to be -178.21, -399.88, -154.18, and 131.62 kcal/mol at 400/sup 0/C. The electrochemical displacement reactions were found to be reversible in LiCl/KCl molten salt cells over a range of 0.0-3.0 Li equivalents per mol at current densities of 5-15 mA/cm/sup 2/. The equilibrium potential vs. Li was found to be a logarithmic function of the calculated oxygen partial pressure for any tie triangle in which Li/sub 2/O is present, or for any tie triangle containing ternary oxide phases Li /SUB x/ MO ...

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

The solvent extraction of 12-phosphotungstic acid, also known as 12-tungstophosphoric acid-H_3PW_1_2O_4_0, the so-called Keggin heteropolyacid - by 0.73 M (20%v/v) tri-n-butyl phosphate (TBP) in n-octane under conditions comparable to those used previously for the extraction of conventional inorganic mineral acids is described. A simplified phase diagram for the pentanary system comprised of H_3PW_1_2O_4_0, HNO_3, H_2O, TBP, and n-octane reveals an extremely low initial concentration of H_3PW_1_2O_4_0 (1.1 mM) at the LOC (limiting organic concentration) condition, far lower than the most effective third-phase-forming inorganic acid, namely HClO_4. The results from small-angle neutron scattering (SANS) indicate that the interparticle attraction energy - U(r) calculated through application of the Baxter sticky sphere model to the SANS data at the LOC condition - does not approach the -2 k_B T value associated with phase ...

Energy Technology Data Exchange (ETDEWEB)

We review the development and application of kinetic Monte Carlo simulations to investigate defect and dopant diffusion in ion implanted silicon. In these type of Monte Carlo models, defects and dopants are treated at the atomic scale, and move according to reaction rates given as input principles. These input parameters can be obtained from first principles calculations and/or empirical molecular dynamics simulations, or can be extracted from fits to experimental data. Time and length scales differing several orders of magnitude can be followed with this method, allowing for direct comparison with experiments. The different approaches are explained and some results presented.

CERN Document Server

Contrary to some previous claims, we find a sizable instanton contribution to the finite energy sum rule used to extract the value of the strong coupling from the measured $\\tau$ decay widths. It is of the same order of magnitude as standard nonperturbative corrections induced by vacuum quark and gluon condensates. Our result indicates that there might be no hierarchy of power corrections in finite energy sum rules at the scale of $\\tau$ mass. Therefore, the standard nonperturbative corrections do not necessarily improve the accuracy of the theoretical predicition, but can rather be used to estimate an intrinsic accuracy of the pure perturbative calculation, which turns out to be rather high on this evidence, of order one percent.

Energy Technology Data Exchange (ETDEWEB)

This paper describes and evaluates the various methods used in the analysis and design of buried pipelines under vehicular crossings extracted from a vast number of literature. It was found that a unified treatment of the subject is currently not available and additional work is required. The study shows that there are sufficient data and technical information that can be integrated to produce sound design. Theoretical as well as empirical formulas are scrutinized and incorporated in their appropriate places. Design examples are presented, complete with the detail calculations. Where applicable nomographs and graphs are adapted as design aids. A brief review of the current safety codes pertaining to natural gas pipeline design is also presented.

International Nuclear Information System (INIS)

For the reuse of a waste salt from an electrorefining process of a spent oxide fuel, a separation of rare earth elements by an oxidative precipitation in a LiCl-KCl molten salt was tested without using precipitate agents. From the results obtained from the thermochemical calculations by HSC Chemistry software, the most stable rare earth compounds in the oxygen-used rare earth chlorides system were oxychlorides (EuOCl, NdOCl, PrOCl) and oxides (CeO2, PrO2), which coincide well with results of the Gibbs free energy of the reaction. In this study, similar to the thermochemical results, regardless of the sparging time and molten salt temperature, oxychlorides and oxides were formed as a precipitant by a reaction with oxygen. The structure of the rare earth precipitates was divided into two shapes: small cubic (oxide) and large plate-like (tetragonal) structures. The conversion efficiencies of the rare earth elements to their ...

Energy Technology Data Exchange (ETDEWEB)

The information reported is for the period October I to December 31, 1993. During this quarter, activities were undertaken in Task 2. Oxygen concentrations were measured in the post-flame region of the entrained flow reactor. The sampling probe was used for the hot gas tests to sample the gas stream. Samples were injected into a gas chromatograph to determine the oxygen concentration. Results agreed with thermoequilibrium calculations that yield equilibrium compositions based on the stoichiometry of the feed gases. The axial temperature distribution along the reactor centerline was measured using a silica-coated platinum-rhodium thermocouple. Two coating techniques were tested and it was found that flame-plating silica to the thermocouple wires produced a thinner coating than a ceramic adhesive technique and therefore a smaller radiation correction. Other activities this quarter included the fabrication of a solids sampling ...

Energy Technology Data Exchange (ETDEWEB)

Experiments on aqueous TiO{sup 2} photocatalytic reaction characteristics of 4 nitrogen-containing and 12 aromatic organic compounds were carried out. Based on the values calculated for the distribution of ionic species and atomic charge, the characteristics of their photocatalytic decomposition were estimated. It was shown that the dependence of decomposition of the N-containing compounds were linearly proportional to their nitrogen atomic charge values, while that of the aromatic compounds were inversely proportional. The effects of aqueous pH, oxygen content and concentration on the TiO{sup 2} photocatalytic characteristics of EDTA-Cu(II) and EDTA-Fe(III) were experimentally investigated. All EDTA systems were decomposed better in the pH range of 2.5{approx}3.0 and with more dissolved oxygen. These results could be applied to a unit process for removal of organic impurities dissolved in a source water of the system ...

Energy Technology Data Exchange (ETDEWEB)

While no mine in Queensland has yet extracted shale oil economically, large resources of oil shale are known to occur throughout the State. These resources have been reported to the Queensland Department of Resource Industries (formerly the Department of Mines) according to a number of different parameters, using numerous methods of calculation and in some instances, detailed and comprehensive supporting information has not been provided. This paper outlines present methods of calculation and reporting of oil shale resources. A more uniform system of reporting resources of Queensland oil shale is desirable to enable an accountable and reliable estimate of resources to be made. It is intended that a code for the reporting of identified oil shale resources based on the present Australian codes for the reporting of identified mineral and coal resources be prepared, and that the importance of determining the level of confidence ...

International Nuclear Information System (INIS)

This report is the user's manual of seismic system reliability analysis code SECOM2 (Seismic Core Melt Frequency Evaluation Code Ver.2) developed at the Japan Atomic Energy Research Institute for systems reliability analysis, which is one of the tasks of seismic probabilistic safety assessment (PSA) of nuclear power plants (NPPs). The SECOM2 code has many functions such as: Calculation of component failure probabilities based on the response factor method, Extraction of minimal cut sets (MCSs), Calculation of conditional system failure probabilities for given seismic motion levels at the site of an NPP, Calculation of accident sequence frequencies and the core damage frequency (CDF) with use of the seismic hazard curve, Importance analysis using various indicators, Uncertainty analysis, Calculation of the CDF taking into account the effect of the correlations of responses and ...

International Nuclear Information System (INIS)

Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of hydrocarbon material ...

Energy Technology Data Exchange (ETDEWEB)

The corrosion resistance of steel-reinforced mortar specimens made from alinite cement was investigated using ordinary Portland cement (OPC) specimens as reference. The specimens were prepared and exposed in three different environments: continuous exposure in tap water, interrupted exposure in tap water, and interrupted exposure in 3.5% NaCl solution. The steel weight loss and the half cell potential were measured vs. exposure time, up to the age of 12 months. Pore solution extraction and analysis and porosity determination were also performed. In continuous exposure in tap water, alinite cement provided adequate protection against corrosion. In interrupted exposure in tap water, a higher corrosion was observed for alinite cement compared to OPC. In the case of interrupted exposure in 3.5% NaCl solution, the simultaneous action of free chlorides and oxygen resulted in the depassivation of steel reinforcing bars in alinite and Portland cement ...

International Nuclear Information System (INIS)

The solubility of Sn(IV) oxide was determined in a dilute NaClO_4 solution with pH 2 through 12 at ambient temperature. Both oversaturation and undersaturation experiments were carried out in an inert gas glovebox where the concentration of the oxygen and carbon dioxide were less than 1 ppm. The solubility of Sn(IV) oxide was 3 x 10"-"8 mol/l at neutral pH, and increased at pH > 7.5. Equilibrium constants of soluble reactions were calculated from the experimental data, using curve fitting method. The study suggests that the solubility of Sn(IV) oxide would be higher than that provisionally used in current safety assessments of HLW disposal sites.

International Nuclear Information System (INIS)

A noninvasive method is described for estimating local cerebral blood flow (LCBF) and local partition coefficients by means of computed tomographic scanning during inhalation of 30% stable xenon gas in oxygen. Time-dependent xenon concentrations in arterial blood and brain tissue during the wash-in and washout phases are used to calculate partition coefficients and LCBF values by means of a least-squares curve-fitting analysis. Control values for partition coefficient and LCBF obtained from control subjects with minor head trauma in the chronic stage were compatible with those in several past reports, and reproducibility was satisfactory. The theoretic grounds underlying this new method of curve-fitting analysis are discussed.

International Nuclear Information System (INIS)

A series of cyclic voltammetry, chronoamperometry and electrochemical impedance experiments have been carried out in order to investigate the effect of cathode composition and porosity on the electrochemical characteristics of strontium-doped lanthanum, praseodymium and gadolinium cobaltite cathodes. The impedance responses at different electrode potentials of the half cell and symmetric single cell setups are compared and analyzed by the equivalent circuit modeling method. The deconvolution of impedance spectra for single cell cathode and anode reactions contributions based on the results of simultaneous analysis of half cells and symmetric single cells has been made by differential impedance real part vs. ac frequency plot analysis method. Noticeable influence of cathode chemical composition, meso-porosity and macro-porosity on the electrochemical activity of the oxygen electroreduction has been demonstrated. Seeming activation energy values have been ...

Energy Technology Data Exchange (ETDEWEB)

Cementitious materials provide an ideal geochemical environment (e.g., high pH pore fluids and large surface areas for sorption) for immobilizing nuclear waste. The inclusion of reducing agents, such as blast furnace slag (BFS) can immobilize radionuclides by forming of solid sulfide phases. Thermodynamic calculations using the MINTEQ geochemical computer code indicate the elemental sulfur present in BPS reacts with the highly mobile pertechnetate anion (TcO{sub 4}{sup -}) anion to form an insoluble technetium sulfide phase (Tc{sub 2}S{sub 7(s)}). Initially, the waste form very effectively immobilizes technetium. However, as oxygen diffuses into the waste form, an outer zone of oxidized concrete and a shrinking core of reduced intact concrete develops. Oxidation of sulfur in the outer zone results in increased technetium concentrations in the pore fluid because Tc{sub 2}S{sub 7(a)} oxidizes to the mobile TcO{sub 4}{sup -} anion. The TcO{sub ...

International Nuclear Information System (INIS)

Contrary to the electronic excitation induced phenomena of desorption and sputtering, we observed incorporation of oxygen in a thin Fe film during its irradiation with swift heavy ions. It is observed that the adsorbed oxygen diffuses in to the Fe film. The incorporation of oxygen and its diffusion in the bulk of the film is a manifestation of extremely large electronic energy deposition by the incident ions. It is shown that the experimentally observed high diffusivity of oxygen in Fe during irradiation is due to the existence of transient melt phase of Fe.

International Nuclear Information System (INIS)

The "2"0 "2"1 "2"2Ne("6Li, d)"2"4 "2"5 "2"6Mg reactions have been studied at a bombarding energy of 32 MeV. Alpha particle spectroscopic strengths have been extracted for several low-lying levels by a finite-range distorted wave analysis. These are compared with theoretical predictions. The agreement is good both for relative strengths to different levels within a nucleus and for ground-state strengths relative to the "1"6O("6Li, d) result. Strengths calculated using eigenfunctions determined in large shell-model computations agree well with pure symmetry SU(3) predictions. The "2"1Ne("6Li, d) angular distributions for transitions to the ground-state band of "2"5Mg are characterized by the lower of the two L-transfers allowed for populating each level. For the 3"+(5.24 MeV) unnatural parity level in "2"4Mg, a two-step calculation gives a better account of the data than does a compound nuclear ...

Science.gov (United States)

The interaction of Pu(IV) and Zr(IV) with citric acid in nitric acid solutions (C/sub HNO/sub 3// greater than 0.1 M) of lithium nitrate was studied by the distribution method in the interval of nitrate ion concentrations from 1 to 6 g-eq/liter. A 40 percent solution of TBP in decane was used as the extraction reagent. It was established that within the range of concentrations studied, complex compounds of plutonium and zirconium are formed: PuHCit/sup 2 +/ and ZrH/sub 2/Cit/sup 3 +/. The concentration equilibrium constants of the reactions of formation of these compounds retain a constant value at constant ionic strength and undergo substantial variation when the total concentration of the nitrate ion in solution is varied. The values of the effective equilibrium constants, calculated considering the change in the activity coefficient of the hydrogen ion, retain a constant value within a wide range of nitrate ion concentrations. It was shown ...

Energy Technology Data Exchange (ETDEWEB)

The excellent high temperature strength and thermal conductivity of molybdenum-base alloys provide attractive features for components in advanced magnetic and inertial fusion devices. Refractory metal alloys react readily with oxygen and other gases. Oxidized molybdenum in turn is susceptible to losses from volatile molybdenum trioxide species, MoO{sub 3}(m), in air and the hydroxide, MoO{sub 2}(OH){sub 2}, formed from water vapor. Transport of radioactivity by the volatilization, migration, and re-deposition of these volatile species during a potential accident involving a loss of vacuum or inert environment represents a safety issue. In this report the authors present experimental results on the oxidation, volatilization and re-deposition of molybdenum from TZM in flowing air between 400 and 800 C. These results are compared with calculations obtained from a vaporization mass transfer model using chemical thermodynamic data for vapor ...

International Nuclear Information System (INIS)

First-principles plane-wave pseudopotential and full-potential linearized-augmented plane-wave methods have been used to study the elastic and electronic properties of several potential superhard RuO_2 phases. The structures, relative stabilities, and the elastic constants and bulk moduli of these phases have been calculated within local-density approximation (LDA) and generalized gradient approximation (GGA). In RuO_2, the LDA and GGA approximations yield smaller and larger lattice constants, respectively, for the Pa3-bar-RuO_2 structure. The internal structural parameter for oxygen atoms in the Pa3-bar structure has a volume dependence that differs from the experimental result and therefore implies a significantly different compression mechanism. The calculated bulk moduli are very similar for the fluorite and Pa3-bar structures and therefore apparently independent of the internal structural parameter. The structure and ...

UK PubMed Central (United Kingdom)

PurposeThe goal of this study was to clarify the dynamics of tumor oxygen (partial pressure of oxygen, pO₂) in SCC VII murine tumors in mice after X-ray...Full Text Available

UK PubMed Central (United Kingdom)

IntroductionThe aim of this study was to evaluate the effects of red blood cell (RBC) transfusions on muscle tissue oxygenation, oxygen metabolism and microvascular reactivity in...Full Text Available

KoreaScience (Korea)

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International Nuclear Information System (INIS)

Ab initio total energy calculations within the framework of density functional theory have been performed for atomic hydrogen and oxygen chemisorption on the (0001) surface of double hexagonal packed (dhcp) americium using a full-potential all-electron linearized augmented plane wave plus local orbitals method. Chemisorption energies were optimized with respect to the distance of the adatom from the relaxed surface for three adsorption sites, namely top, bridge, and hollow hcp sites, the ad-layer structure corresponding to the coverage of a 0.25 monolayer in all cases. Chemisorption energies were computed at the scalar-relativistic level (no spin-orbit coupling NSOC) and at the fully relativistic level (with spin-orbit coupling SOC). The two-fold bridge adsorption site was found to be the most stable site for O at both the NSOC and SOC theoretical levels with chemisorption energies of 8.204 eV and 8.368 eV respectively, while the three-fold ...

Science.gov (United States)

The extraction of magnesium by tributyl phosphate from KI solutions was investigated. With increasing KI and TBP concentrations, the extraction increased. The maximum extraction (82%) was attained at pH 4, and it did not decrease with a further pH increase. With decreasing pH, the extraction decreased because of HI extraction. The magnesium was extracted as the compound MgI/sub 2/ x 4TBP. Complexone III (at pH 3-4) does not affect the extraction of magnesium, which makes it possible to use it to mask other metals.

Science.gov (United States)

The FFTF reactor is described. Procedures and equipment used to protect personnel from potential hazards of oxygen deficient environments are described.

Science.gov (United States)

... 5.9-585/T; thermal stability; solubility in liquid nitrogen, oxygen and Freons; molar extinction coefficients in the visible range and EPR spectrum. ...

Energy Technology Data Exchange (ETDEWEB)

In a forthcoming paper we describe a new approach to rapidity gap survival (RGS) in the production of high-mass systems (H = dijet, Higgs, etc.) in exclusive double-gap diffractive pp scattering, pp -> p + H + p. It is based on the idea that hard and soft interactions are approximately independent (QCD factorization), and allows us to calculate the RGS probability in a model-independent way in terms of the gluon generalized parton distributions (GPDs) in the colliding protons and the pp elastic scattering amplitude. Here we focus on the transverse momentum dependence of the cross section. By measuring the ''diffraction pattern'', one can perform detailed tests of the interplay of hard and soft interactions, and even extract information about the gluon GPD in the proton from the data.

Energy Technology Data Exchange (ETDEWEB)

Measurement results of total interaction cross sections averaged by the spectrum of ultracold neutrons (UCN) within the rate range from 3.2 to 5.7 m/s at the temperatures of 80 and 300 K for the following gases: hydrogen, parahydrogen, helium-4, nitrogen, neon, argon, xenon are presented. The experiment has been conducted conducted in the facility for UCN extraction, mounted in the radial channel of the WWR-K reactor. Experimental dependences of UCN counting rate on pressure of the investigated gases in the chamber varying from 0 to 1.5x10/sup 3/ torr are presented graphically. The measured total cross sections mainly satisfactorily agree with calculations, divergences are observed only for hydrogen and xenon.

CERN Document Server

We formulate a complete theory of Edge Radiation based on a novel method relying on Fourier Optics techniques. Similar types of radiation like Transition Undulator Radiation are addressed in the framework of the same formalism. Special attention is payed in discussing the validity of approximations upon which the theory is built. Our study makes consistent use of both similarity techniques and comparisons with numerical results from simulation. We discuss both near and far zone. Physical understanding of many asymptotes is discussed. Based on the solution of the field equation with a tensor Green's function technique, we also discuss an analytical model to describe the presence of a vacuum chamber. In particular, explicit calculations for a circular vacuum chamber are reported. Finally, we consider the use of Edge Radiation as a tool for electron beam diagnostics. We discuss Coherent Edge Radiation, Extraction of Edge Radiation by a mirror, and ...

International Nuclear Information System (INIS)

High-spin states in "1"7"7Ta were produced using the "1"7"0Er("1"1B, 4n) reaction at 55 and 60 MeV. Considerable extensions have been made to the previously known level scheme, and new structures have been found. B(M1)/B(E2) ratios have been extracted for strongly coupled bands. The behavior of the different rotational cascades, in particular the anomalous crossing frequency observed in the [541]1/2"- proton h_9_/_2 band and the occurrence of ''identical bands,'' is discussed. Comparisons are made with projected shell model calculations.

Energy Technology Data Exchange (ETDEWEB)

We present a phenomenological model of the quark-hadron transition in neutrino-nucleon scattering. Using recently extracted weak nucleon transition form factors, we investigate the extent to which local and global quark-hadron duality is applicable in the neutrino F{sub 1}, F{sub 2} and F{sub 3} structure functions, and contrast this with duality in electron scattering. Our findings suggest that duality works relatively well for neutrino-nucleon scattering for the F{sub 2} and F{sub 3} structure functions, but not as well for F{sub 1}. We also calculate the quasi-elastic, resonance and deep inelastic contributions to the Adler sum rule, and find it to be satisfied to within 10% for 0.5 < Q{sup 2} < 2 GeV{sup 2}.

Science.gov (United States)

A methodology and hypothetical case study are presented for incorporation of uncertainty and variability into calculations of human health risk appropriate for regional, or basin-scale, groundwater management problems. Uncertainty in well water concentration is introduced through complex contaminant migration patterns in the subsurface. Variability is considered in parameters related to individual behavior patterns and biological effects and to groundwater extraction and distribution networks. A joint uncertainty and variability (JUV) analysis is used to generate a two-dimensional distribution or risk surface that spans both transport uncertainty as well as individual variability. Cuts in this distributional surface (fractiles of variability and percentiles of uncertainty) are presented and discussed. Comparisons with alternative approaches based upon deterministic transport models are also made. In addition, important distinctions are made ...

International Nuclear Information System (INIS)

A more complete level scheme is presented here for the decay of "1"8"7Pt, incorporating many new lines and levels up to 2.4 MeV. Emphasis has been placed on the extraction of multipole mixing ratios from nuclear orientation data. Analysis of that data, however, required a more complete understanding of the level structure (including, in particular, branching ratios, conversion coefficients, and level feedings), prompting the collection of new spectroscopy data. The low-lying, positive-parity levels are described in terms of (odd-proton) single-particle Nilsson states coupled to a triaxial core. Multipole mixing ratios are compared to those calculated in the Particle-Plus-Triaxial-Rotor Model. (orig.).

British Library Electronic Table of Contents (United Kingdom)

Abstract Four methods were used to extract length scales from mixing data: the maximum striation thickness, point-to-nearest-neighbour (PNN) distributions, the correlogram and the variogram. Four test data sets were analysed: blending in a micromixer; particle dispersion in a stirred tank; dispersion of a smoke plume and a pulse tracer test in a reactor. The maximum striation thickness captures the largest length scale. The PNN method quantifies differences between clustered, random and regular spatial distributions. The correlogram calculation cannot be consistently used for all types of mixing data and has therefore been rejected. The variogram reveals both large-scale segregation and periodicity. Sub-sampling is needed to isolate smaller structures. The variogram, PNN and transect metho...

Energy Technology Data Exchange (ETDEWEB)

Considerable effort worldwide has been put into trying to find the best way to utilise the large amount of energy that we put into our dustbins every day. One of the problems encountered is that the waste collection systems tend to gather together in one place between 400 and 1000 t of the stuff everyday and since it is possible to extract rather more than 2 MW from each tonne, that is a lot of energy for which to find a market. In continental European cities, especially Germany, and Sweden with most of the population living in apartment blocks, and with colder winters than the UK, district heating provides a suitable market. With its milder winters, more diverse housing and cheap gas the UK is not such a fertile ground for district heating. But since the passing of the Energy Act in 1984, there is a steady market in electricity generation with the advantage that the purchase tariffs are published so that income can be accurately calculated.

International Nuclear Information System (INIS)

Radon concentrations were continuously measured outdoors, in living room and basement in 10-minute intervals for a month. The radon time series were analyzed by comparing algorithms to extract phase-space dynamical information. The application of fractal methods enabled to explore the chaotic nature of radon in the atmosphere. The computed fractal dimensions, such as Hurst exponent (H) from the rescaled range analysis, Lyapunov exponent (#lambda# ) and attractor dimension, provided estimates of the degree of chaotic behavior. The obtained low values of the Hurst exponent (0calculated fractal dimensions of attractors indicated more influencing (meteorological) parameters on radon in the atmosphere. ...

Energy Technology Data Exchange (ETDEWEB)

The thermal analysis of a turbine stack discharging exhaust gases to the atmosphere is presented. The examined turbine stack belongs to a gas lift plant for oil extraction located in the Gulf area. The analysis has been performed because an overheating of the anchor flange/bolts and of the concrete foundation occurred and caused small cracks in the upper layer of the foundation. A qualitative thermal analysis of the stack has pointed out that the main cause of the overheating was the thermal radiation in the air-filled region underneath the stack bottom plate. Detailed calculations performed by using a CFD code (Fluent ver. 6.0.12), cross-checked with measurements taken from site, have shown that a significant reduction of the heat flux to the foundation could be obtained by filling the above mentioned air region with an insulating material. The benefits of this solution are prevailing over those achievable with the installation of external ...

International Nuclear Information System (INIS)

This chapter consists of some points including an introduction, the basic parts of mass spectroscope device, sample introduction into the inductively coupled plasma, pneumatic nebuliser, ultrasonic nebuliser, dry gas cloud system, laser ablation unit, inductively coupled plasma-ion source, extraction of ions from ion source, mass analysis, quad-polar mass spectrometer, dual assembly mass spectrometer, mass spectrometer by calculation of time of flight, ion interferences and the ability of resolution, ion counter, working conditions of inductively coupled plasma mass spectroscope device, efficiency of ion transportation in an inductively coupled plasma mass spectroscope device and applications of analysis using mass spectroscope of induced plasma including nuclear, industrial, geological, environmental and archaeological applications, measurement of isotopes ratio and applications in tracing crimes.

International Nuclear Information System (INIS)

We present accurate tight-binding parametrizations of the first-principles augmented-plane-wave or linear-augmented-plane-wave band structures of LaCuO_3, La_2CuO_4, Ba_2CuO_4, and the high-temperature superconductor YBa_2Cu_3O_7. We discuss the methodology and efficient application of these fits, including as an example our tight-binding coherent-potential-approximation (CPA) calculations of the effects of disorder on the electronic structure of La/sub 2-//sub x/Ba/sub x/CuO/sub 4-//sub y/. Our CPA calculations support the hypothesis of a rigid-band lowering of the Fermi level for La/sub 2-//sub x/Ba/sub x/CuO_4, enhancing the density of states there. However, for La_2BaCuO/sub 4-//sub y/ they yield the interesting result that oxygen vacancies also lower E/sub F/ and raise N(E/sub F/). This is a significant result for the theory of superconductivity in these materials. In addition to CPA calculations, ...

British Library Electronic Table of Contents (United Kingdom)

Three alternative extraction procedures were carried out in order to separate the antioxidant components and isolate an efficient extract from Origanum dictamnus. Procedure A included sequential extractions with petroleum ether (PE), diethyl ether (DE) and ethanol; procedure B sequential extractions with PE and ethyl acetate (EAc); procedure C a single step extraction with ethanol. The most efficient radical scavengers, according to the DPPH method, were isolated in ethanol extract of procedure A (mainly rosmarinic acid), followed by ethanol extract of procedure C. However, both ethanol extracts had low solubility in oil and could not protect it. EAc and DE extracts, containing mainly apigenin and epirosmanol ethyl ether, presented lower radical scavenging activity but were very effective ...

International Nuclear Information System (INIS)

We have measured the lattice relaxation around As in Si at a homogeneous As concentration of 4x10"1"8 cm"-"3 by EXAFS spectroscopy. From the absorption spectra, distances up to the 4th shell could be extracted. A sizeable misfit due to an increased distance is only observed for the 1st shell. Complementing our experimental work we have performed ab initio calculations based on the density functional theory with the WIEN97 package which uses the linearised augmented plane wave method and with the FHI96md program which uses first-principles pseudo-potentials and a plane wave basis set to investigate the size dependence of the super-cells constructed around one substitutional As atom. The calculations yielded good agreement with our EXAFS experiment so that the determined relaxations can be used as a solid basis for further interpretations of derived parameters such as hyperfine interaction parameters in defect complexes.

International Nuclear Information System (INIS)

For the selective extraction of radionuclides from nitrate media, the extractabilities of organo-poly-phosphine poly-oxides were examined in the form of impregnated resins. It was found that the extractability of 1,1,3,5,5-pentaphenyl-1,3,5-tri-phospha-pentane trioxide (PPTPT) for U(VI) is quite unusual with very high values at both low and high concentrations of nitric acid, which is not observed for other types of extractants. Thus, this extractant might be promising for the selective extraction of U(VI) in very high concentrations of HNO3. (authors)

Science.gov (United States)

... oxygen to the tissues in the body),nicotinamide adenine dinucleotide (NADH) deficiency (a genetic condition), glucose-6- ...

International Nuclear Information System (INIS)

We report the oxygen, hydrogen, and deuterium effects on nitrogen implantation of stainless steel. Oxygen is absorbed on the surface creating a potential barrier and diminishing the nitrogen retention. Deuterium removes more oxygen from the surface than hydrogen, augmenting the nitrogen chemical potential and yielding faster nitrogen diffusion into the bulk material.

International Nuclear Information System (INIS)

... defects doped materials germanium infrared radiation monocrystals neutron

KoreaScience (Korea)

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DEFF Research Database (Denmark)

The multiple responses of fishes to changes in dissolved oxygen saturations have been studied widely in the laboratory. In contrast only few studies have included field observations. The objective of the present study was to evaluate the performance of a novel acoustic dissolved oxygen transmitter for field biotelemetry. The results demonstrated that the output of the transmitter was unaffected by three different temperatures (10 to 30 degrees C) and described the dissolved oxygen saturation with high accuracy (r(2) > 0.99) over the entire range of 0 to 191% saturation. The response time (>= 90% of end value) of the transmitter was 12 s both in terms of decreasing (100 to 0%) and increasing (0 to 100%) oxygen saturations. When externally attached to fishes the present findings support the use of the transmitter for reliable dissolved oxygen measurements on individuals living ...

Energy Technology Data Exchange (ETDEWEB)

The thermal stability of wood polymer composites made with extractive-free wood from four different wood species was studied. Hot water (HW) extractives, ethanol/cyclohexane (E/C) extractives and both types of extractives were eliminated from A. cyclops, E. grandis, P. radiata and Q. alba. Composites of LLDPE and 10 wt% of wood were prepared, using poly vinyl alcohol-co-ethylene (EVOH) as a compatibilizer. The thermal degradation behavior of the composites was characterized with thermogravimetric analysis (TGA). The obtained results showed that in all cases, the degradation temperatures shifted to higher values after removal of the extractives. The removal of E/C extractives was less effective in its improvement of the thermal stability than the removal of HW extractives. The largest improvement on the thermal stability of WPCs was achieved ...

Energy Technology Data Exchange (ETDEWEB)

To improve mirrors coating, we have modeled sputtering of binary oxide targets using TRIM code. First, we have proposed a method to calculate TRIM input parameters using on the one hand thermodynamic cycle and on the other hand Malherbe`s results. Secondly, an iterative processing has provided for oxide steady targets caused by ionic bombardment. Thirdly, we have exposed a model to get experimental sputtering yields. Fourthly, for (Ar - SiO{sub 2}) pair, we have determined that steady target is a silica one. A good agreement between simulated and experimental yields versus ion incident angle has been found. For (Ar - Ta{sub 2} O{sub 5}) pair, we have to introduce preferential sputtering concept to explain discrepancy between simulation and experiment. In this case, steady target is tantalum monoxide. For (Ar - Ta+O{sub 2}) pair, tantalum sputtered by argon ions in reactive oxygen atmosphere, we have to take into account new concept of oxidation ...

Energy Technology Data Exchange (ETDEWEB)

CuO/bentonite and CuO-BHA nanocomposites were studied as oxygen carriers in chemical-looping combustion (CLC) of simulated synthesis gas. Global reaction rates of reduction and oxidation, as the function of reaction conversion, were calculated from 10-cycle oxidation/reduction tests utilizing thermogravimetric analysis at atmospheric pressure between 700 and 900{degree}C. It was found that the reduction reactions are always faster than oxidation reactions; reaction temperature and particle size do not significantly affect the reaction performance of CuO/bentonite. Multicycle CLC tests conducted in a high-pressure flow reactor showed stable reactivity for production of CO{sub 2} from fuel gas at 800 and 900{degree}C and full consumption of hydrogen during the reaction. Results of the tapered element oscillating microbalance showed a negative effect of pressure on the global rates of reduction-oxidation reactions at higher fractional conversions. ...

Science.gov (United States)

The performance of 250 different computational protocols (combinations of density functionals, basis sets and methods) was assessed on a set of 165 well-established experimental (1)H-(1)H nuclear coupling constants (J(H-H)) from 65 molecules spanning a wide range of "chemical space". Thereby we found that, if one uses core-augmented basis sets and allows for linear scaling of the raw results, calculations of only the Fermi contact term yield more accurate predictions than calculations where all four terms that contribute to J(H-H) are evaluated. It turns out that B3LYP/6-31G(d,p)u+1s is the best (and, in addition, one of the most economical) of all tested methods, yielding predictions of J(H-H) with a root-mean-square deviation from experiment of less than 0.5 Hz for our test set. Another method that does similarly well, without the need for additional 1s basis functions, is B3LYP/cc-pVTZ, which is, however, ca. 8 times more "expensive" in ...

Energy Technology Data Exchange (ETDEWEB)

Solar ultraviolet radiation is damaging for living organisms due to its high energy pro each photon. The UV radiation is often separated into three regions according to the wavelength: UVC (200-280 nm), UVB (280-320 nm) and UVA (320-400 nm). The most hazardous part, UVC is absorbed completely in the upper atmosphere by molecular oxygen. UVB radiation is absorbed by atmospheric ozone partly, and it is reaching Earth`s surface, as UVA radiation. Besides atmospheric ozone, very important factors in determining the intensity of UVB radiation globally are the solar zenith angle and cloudiness. It may be calculated from global ozone changes that the clear-sky UVB doses may have enhanced by 10-15 % during spring and 5-10 % during summer at the latitudes of Finland, following the decrease of total ozone between 1979-90. The Finnish ozone and UV monitoring activities have become a part of international activities, especially the EU Environment and ...

International Nuclear Information System (INIS)

In this thesis, a new ab-initio method for molecular dynamics within the framework of density functional theory was developed and implemented. It is strongly related to the projector-augmented-wave method (PAW) by P. Bloechl, but also includes elements of a pseudocharge method proposed by M. Weinert for the full-potential linearized augmented plane wave method (FLAPW). Like the FLAPW-method, the PAW-method is an all-electron method. In the later case, the hamiltonian takes quite a simple form similar to the one obtained when using normconserving Kleinman-Bylander-type pseudopotentials or ultrasoft Vanderbilt pseudopotentials. The PAW-method allows for an efficient calculation of systems containing virtually any element of the periodic table, including those which require high numerical effort when treated using normconserving pseudopotentials (e.g. 2p-elements like oxygen or 3d-transitional metals like copper). In addition, a higher accuracy ...

International Nuclear Information System (INIS)

Marker experiments for studying the mass transport through a palladium silicide layer on a crystalline substrate during thermal oxidation at 700 to 850 deg C have been reported recently. In this work argon gas embedded in amorphous silicon during sputtering was implemented as the inert marker and the oxidation of PdSi was processed above 900 deg C. At this high-temperature oxidation silicon-rich silicide PdSisub(y), with y exceeding 5, may be obtained. This can be anticipated by considering the Pd-Si phase diagram which shows the liquid phase may appear at an annealing temperature above 892 deg C. As a result, a non-stoichiometric and non-uniform silicide layer may develop at the sample surface. Marker analysis showed that both palladium and silicon dissociated at the Pdsub(x)Si/ SiO_2 interface and moved to the substrate with the silicon being the dominant diffuser. The Rutherford backscattering spectra (RBS) showing the oxide film and composition isothermally annealed at 900 deg C is ...

International Nuclear Information System (INIS)

The EUROTRAC sub-project ''Tropospheric Ozone Research'' (TOR) follows a dual strategy: - Observation of the chemical processes contributing to the oxygen balance directly in the atmosphere; - Establishment of a validated data base for model calculations. Both tasks require simultaneous measurements of a wide range of chemical and meteorological components. In the case of the investigation of the chemical processes, it is also desirable to measure the free radicals directly involved in ozone production. In the project described, a measuring station was set up. For a period of two years and a half, continuous measurements were made of ozone and its chemical precursors (NO, NO_2, NO_y, VOC, CO), as well as other photooxidants (H_2O_2 and organic hydroperoxides, organic nitrates), the photolysis frequency of NO_2, and meteorological parameters (wind, temperature, moisture, aerosols). The station was located on the Schauinsland mountain in the ...

British Library Electronic Table of Contents (United Kingdom)

A new cis-dioxomolybdenum complex MoO2(DMLA)2 (DMLA=N,N-dimethyllactamide) has been synthesized and characterized by X-ray crystallography, H NMR and IR spectroscopies and electronic structure calculations at DFT/B3LYP level. This compound (chemical formula C10H20MoO6N2) crystallizes in the orthorhombic space group P212121 with Z=4, a=6.9357(2)?, b=11.8761(4)?, c=17.7251(5), V=1460.00(8)?3 and renders a slightly distorted octahedral structure with two long Mo-O bonds (2.253(3)? and 2.257(3)?) trans to each of the MoO groups and with two short Mo-O bonds of 1.942(3)4? cis to them. The MoO bond length are 1.715(3) and 1.704(3)?). Each lactamide ligand is bidentate; they are coordinated in their deprotonated form with the carbonyl oxygen occupy...

Energy Technology Data Exchange (ETDEWEB)

Optical frequency comb technology has been used in this work for the first time to investigate the nuclear structure of light radioactive isotopes. Therefore, three laser systems were stabilized with different techniques to accurately known optical frequencies and used in two specialized experiments. Absolute transition frequency measurements of lithium and beryllium isotopes were performed with accuracy on the order of 10{sup -10}. Such a high accuracy is required for the light elements since the nuclear volume effect has only a 10{sup -9} contribution to the total transition frequency. For beryllium, the isotope shift was determined with an accuracy that is sufficient to extract information about the proton distribution inside the nucleus. A Doppler-free two-photon spectroscopy on the stable lithium isotopes {sup 6,7}Li was performed in order to determine the absolute frequency of the 2S {yields} 3S transition. The achieved relative accuracy of 2 x 10{sup -10} is ...

Energy Technology Data Exchange (ETDEWEB)

The oxidation of boron carbide in steam or air was recently extensively studied especially in Forschungszentrum Karlsruhe, Institut fuer Materialforschung. An important data set is available for the interaction modelling. An oxygen diffusion model through the superficial liquid boron oxide formed on the boron carbide external surface associated to a superficial reaction between the liquid boron oxide and steam is proposed to simulate the experimental kinetics from BOX rig and thermogravimetric tests on the interaction between steam and boron carbide at a temperature range 800 C to 1400 C. The oxygen diffusion model will be also useful to simulate interaction between boron carbide and Ar+O2 (air simulation) atmosphere when the steam pressure becomes zero. From the analysis of BOX rig experimental kinetics of non-condensable (H2, CO2, CO and CH4) gases we propose an oxygen diffusion model through the liquid boron oxide and a ...

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This paper studies the analytical application of europium (III)-morin complex which is formed in alkaline medium and has an intense color. The extent of europium extraction was determined by adding to the extract a morin solution in isoamyl alcohol in a 50-100-fold excess with respect to europium. The dependence of the optical density of the extracts on the ph in the system europium (III)-morin-water-organic solvent for different excesses of the reagent is shown: this indicates formation of two extractable complexes, one being dominant in the pH range 4-7, the other at pH greater than or equal to 8.5. The extraction of the europium (III)-morin complex from alkaline solution is used for direct extraction-photometric determination of europium(III) in compounds of elements having amphoteric properties or forming amines (Zns, Mo0/sub 3/).

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Density functional theory (DFT) calculations using plane-wave methods were performed for Li2TMPO4F, LiTMPO4F, and TMPO4F (TM=V, Mn, Fe, Co, Ni) to address their feasibility as high-voltage cathode materials for Li ion batteries. We computed their structures, average open circuit voltages, and thermal stabilities for step-wise lithiation/delithation (discharge/charge) reactions. The calculations suggest that associated unit cell volume changes are sufficiently small on average that they should not be a significant detriment to the mechanical stability of the cathode. In the nickel case, the calculated volume change deviates from the series by increasing during the first delithiation step. Furthermore, the volume increases for all these materials during the second delithiation step. It appears that the relative volume expansion in the series during delithiation is directly correlated to the degree of d-p rehybridization. ...

Science.gov (United States)

Graphene nanosheets (GNSs) were synthesized and used as cathode active materials in a nonaqueous lithium-oxygen battery. The GNSs electrode delivered an extremely high discharge capacity in comparison to carbon powders, which is attributed to its unique morphology and structure. PMID:21779551

UK PubMed Central (United Kingdom)

It is generally accepted that hypoxia and recovery from oxygen deprivation contribute to the breakdown and ulceration of human skin. The effects of these stresses on proliferation, differentiation...Full Text Available

UK PubMed Central (United Kingdom)

The theory that the αβ dimer is the functional unit of cooperativity in hemoglobin has been tested by determination of the oxygen equilibrium curve of stable deoxy dimers, obtained by...Full Text Available

UK PubMed Central (United Kingdom)

Laboratory studies investigated the influence of dissolved oxygen tension (DOT) on microbial degradation of hexadecane in cultures with sediment-seawater suspensions. With a fermentor system, it was...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The effect of dissolved oxygen and copper on denting corrosion at 280/sup 0/C in solutions of NaCl at pH 9 with ammonia was investigated using a packed tube/support plate crevice in a laboratory simulation. The onset of corrosion was detected with a hydrogen analyzer sensitive to 0.2 ppB. In the absence of copper, rapidly rising hydrogen concentrations were detected only when the product of the chloride and oxygen concentrations were detected only when the product of the chloride and oxygen concentrations in the boiler-water exceeded 25 (ppM)/sup 2/, but at these high concentrations, unheated low-carbon steel surfaces in the system were as sensitive to corrosion as the heated crevice. When copper metal was present in the feed system, corrosion of the heated crevice occurred in the absence of oxygen, provided the copper had previously been exposed to dissolved oxygen. Dosing ...

UK PubMed Central (United Kingdom)

A two-channel optical system has been developed to provide spatially resolved simultaneous imaging of singlet molecular oxygen (¹O₂) phosphorescence and photosensitizer (PS) fluorescence...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Disclosed are additives for hydrocarbon fuels which are the reaction products of a polyamine and an alkyl ester of acrylic or alkyl acrylic acid. A preferred composition is a mixture of the reaction product and oxygenated or non-oxygenated mono- or polyamines.

British Library Electronic Table of Contents (United Kingdom)

Oxidation of propylene with oxygen, air and a mixture of nitrogen?oxygen in a barrier discharge is investigated. The selectivity towards formation of propylene oxide in pure oxygen is shown to be as high as 45 wt% and the propylene conversion ratio is found to be 12.9 wt%. In the oxidation with air, the propylene oxide selectivity is 23 wt%, while the conversion is 7.5 wt%. The values of propylene conversion and selectivity towards formation of propylene oxide in a barrier discharge are consistent with those obtained by the thermocatalytic methods for production of propylene oxide.

KoreaScience (Korea)

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International Nuclear Information System (INIS)

The manufacturing of TRIGA fuel rods with low enriched uranium follows in principle the same route as high-enriched uranium. The high purity of the primary metals (uranium, zirconium and erbium) is important for determining the equilibrium metal-hydrogen phases. The impurities from the metal, on the surface and from hydrogen may have an important influence on the hydriding process. This paper presents the aspects of the fuel contamination with oxygen during the manufacturing process of the low enriched uranium fuel. The continuous control of the oxygen concentration in the working zone ensures avoidance of the accidental contamination. Key words: manufacturing, fuel, oxygen, contamination. (authors)

International Nuclear Information System (INIS)

Starting from the Molten Salt Breeder Reactor project of Oak-Ridge, we have performed parametric studies in terms of safety coefficients, reprocessing requirements and breeding capabilities. In the frame of this major re-evaluation of the molten salt reactor (MSR), we have developed a new concept called Molten Salt Fast Reactor or MSFR, based on the Thorium fuel cycle and a fast neutron spectrum. This concept has been selected for further studies by the MSR steering committee of the Generation IV International Forum in 2009. Our reactor's studies of the MSFR concept rely on numerical simulations making use of the MCNP neutron transport code coupled with a code for materials evolution which resolves the Bateman's equations giving the population of each nucleus inside each part of the reactor at each moment. Because of MSR's fundamental characteristics compared to classical solid-fuelled reactors, the classical Bateman equations have to be modified by adding two terms representing the ...

Energy Technology Data Exchange (ETDEWEB)

A set of equations describing a stress-mediated evolution of the nonequilibrium dopant-defect system has been derived and analyzed. Together with coupled diffusion of dopant atoms and point defects, we consider the drift of all mobile species in different charge states, namely vacancies, self-interstitials, and pairs 'dopant atom-point defect', in the field of stress. It has been shown that stresses may affect the diffusion of dopant atoms mainly in two ways: (1) directly, due to the drift of the pairs in the field of stress; (2) indirectly, by the formation of nonuniform defect distribution due to the drift of point defects. On this basis, various features of doping processes, such as phenomena of 'uphill' impurity diffusion near the surface (within the framework of the first or second mechanisms) and the peculiarities of high concentration phosphorus diffusion (due to the second mechanism), can be explained. Numerical computations of high ...

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Using the constrained-curve fitting method and overlap fermions with the lowest pion mass at 180 MeV, we observe that the masses of the first positive and negative parity excited states of the nucleon tend to cross over as the quark masses are taken to the chiral limit. Both results at the physical pion mass agree with the experimental values of the Roper resonance (N{sup 1/2+}(1440)) and S{sub 11} (N{sup 1/2-}(1535)). This is seen for the first time in a lattice QCD calculation. These results are obtained on a quenched Iwasaki 16{sup 3}x28 lattice with a=0.2 fm. We also extract the ghost {eta}{sup '}N states (a quenched artifact) which are shown to decouple from the nucleon interpolation field above m{sub {pi}}{approx}300 MeV. From the quark mass dependence of these states in the chiral region, we conclude that spontaneously broken chiral symmetry dictates the dynamics of light quarks in the nucleon.

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Using the constrained curve fitting method and overlap fermions with the lowest pion mass at 180 MeV, we observe that the masses of the first positive and negative parity excited states of the nucleon tend to cross over as the quark masses are taken to the chiral limit. Both results at the physical pion mass agree with the experimental values of the Roper resonance (N{sup 1/2+} (1440)) and S{sub 11} (N{sup 1/2-}(1535)). This is seen for the first time in a lattice QCD calculation. These results are obtained on a quenched Iwasaki 16{sup 3} x 28 lattice with a = 0.2 fm. We also extract the ghost {eta}{prime} N states (a quenched artifact) which are shown to decouple from the nucleon interpolation field above m{sub {pi}} {approx} 300 MeV. From the quark mass dependence of these states in the chiral region, we conclude that spontaneously broken chiral symmetry dictates the dynamics of light quarks in the nucleon.

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An engineering tool incorporating a scanning infrared radiometer, an image digitizer, a microcomputer, and the software to drive the system was developed to allow remote mapping of the temperature distribution in solar cavity receivers. Using enclosure analysis, the infrared image processing program extracts the irradiance map from the radiosity map of the cavity to yield an emissive power map. Using the calibration curve of the radiometer and the emissivity of the surface of the cavity, the emissive power map is transformed into a temperature map. The system was tested by comparing its calculated temperatures to temperatures measured by thermocouples at several locations on the surfaces of heated model cavity receivers. The average relative error for the cavities ranged from 4.6%--34.9%, with the relative error on the base usually less than half that on the wall. Some work was also carried out to compensate the detected radiosity field for the ...

Energy Technology Data Exchange (ETDEWEB)

In 1986, the National Research Council, through its Energy Engineering Board, formed the Committee on Geothermal Energy Technology. The committee's study addressed major issues in geothermal energy technology, made recommendations for research and development, and considered cooperative arrangements among government, industry, and universities to facilitate RandD under current severe budget constraints. The report addresses four types of geothermal energy: hydrothermal, geopressured, hot dry rock, and magma systems. Hydrothermal systems are the only type that are now economically competitive commercially. Further technology development by the Department of Energy could make the uneconomical hydrothermal resources commercially attractive to the industry. The economics are more uncertain for the longer-term technologies for extracting energy from geopressured, hot dry rock, and magma systems. For some sites, the cost of energy derived from geopressured and ...

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The purpose of this project was to investigate the feasibility of an antiproton catalyzed fission fragment rocket (FFR). The FFR is characterized by the extraction of fission fragments from the fissile fuel, and the utilization of their kinetic energy for thrust generation. A significant drawback to previous FFR designs was the requirement to maintain a critical nuclear pile as the fission fragment source. The author examined the possibility of replacing the critical pile with a sub-critical pile driven by antiprotons. Recent experiments have revealed that antiprotons stimulate highly energetic fissions in {sup 238}U, with a neutron multiplicity of 13.7 neutrons per fission. This interaction was used as a throttled neutron source. The pile consisted of layers of fissile coated fibers which are designed to allow fission fragments to escape them, where the fragments collide with a fluid. The heated fluid is then ejected from the rocket to provide thrust. The ...

Energy Technology Data Exchange (ETDEWEB)

An adjustment support system using computer for start-up operation of cyclotron is being developed in order to support operators who, using their experiences and intuition, tune up dozens of components to maximize beam efficiency. This paper describes a method of beam pattern diagnosis and adjustment guidance based on fuzzy relation as one function of the adjustment support system. The followings are the basic processes of this method. (1) The computer extracts features of beam pattern which correspond with operators' criteria. (2) The computer calculates causative possibility of each adjustment parameters by inverse operation of fuzzy relational equation, which formulates the relationship between criteria of beam pattern and adjustment parameters. (3) The computer displays those causative probabilities in a graphical manner as a operation guidance. Not only the probabilities but also the criteria of beam pattern and their relationship ...

International Nuclear Information System (INIS)

Laser flash photolysis studies of tetraphenyl-p-dioxin have led to the characterization of its triplet state. The T-T absorption spectra shows maxima at 350 and 545 nm; the triplet has a lifetime of 535 ns in methanol and can be quenched by di-tert-butyl nitroxide, paraquat dications, oxygen, and di-tert-butyl selenoketone. The interaction of the triplet with oxygen leads to the formation of singlet oxygen which in turn reacts with the title compound to yield benzil.

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No abstract prepared.

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Crude N,N-dialkylcarbamoylmethylphosphonates and phosphine oxide extractants, and particularly crude dihexyl N,N-diethylcarbamoylmethylphosphonate and octylphenyl N,N-diisobutylcarbamoyl phosphine oxide, are purified by distilling the crude materials in a thin film evaporator. Preferably, the crude materials are reacted with concentrated hydrochloric acid and then with aqueous sodium hydroxide prior to distillation in the thin film evaporator to hydrolyze impurities contained in them. The purified extractants are useful for extracting actinides and lanthanides from liquid waste streams. (author).

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Energy Technology Data Exchange (ETDEWEB)

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Science.gov (United States)

PMID:21545471

Science.gov (United States)

A process is described for the recovery of uranium values from phosphoric acid utilizing an alkyl pyrophosphoric acid (Appa) primary extractant. After extracting the uranium from the phosphoric acid, the appa extractant is deactivated by heating and the uranium values stripped into a phosphoric acid strip solution containing ferric ion as a salting agent. The uranium values may then be re-extracted directly from this stripping solution without adjustment of its concentration into a dialkyl phosphoric acid trialkyl phosphine oxide synergistic extractant from which a relatively pure yellow cake is precipitated. A new procedure for preparing the requisite appa primary extractants is also disclosed.

British Library Electronic Table of Contents (United Kingdom)

Extracts were prepared from leaf, bark, and seed of Azadirachta indica, leaf and seed of Prunus persica, bark of Mangifera indica, and leaf of Psidium guajava and were evaluated against Boophilus microplus. Of the eight extracts screened, the extracts prepared from the A. indica seed showed very high level of efficacy (80%) after 5?h of treatment. Besides the immediate effect on adult ticks, the egg-laying properties of the survived ticks was also assessed, and a significant reduction (P?A. indica seed extracts was noted in comparison to control. The efficacy of the neem seed extracts was compared with the commonly used synthetic pyrethroids, and comparable efficacy against B. microplus fed on animals treated with neem seed extracts and acaricide treated was noted. The possibility of using...

Energy Technology Data Exchange (ETDEWEB)

Periphyton is typically a heterogeneous assemblage of filamentous and single celled photoautotrophic and heterotrophic micoorganisms suspended in a mucopolysaccharide matrix which they produce. By definition, the assemblage is attached to a substratum such as rock, sediment, or plant in an aquatic environment. Microtechniques with high spatial and temporal resolution are required to define metabolic interactions among the heterotrophic and autotrophic constituents, and between periphyton and its environment. This study used oxygen sensitive microelectrodes with tip diameters of < 30 m to investigate the effects of photosynthesis and respiration on the oxygen dynamics of several diverse periphyton communities both in situ and in laboratory microcosms. A novel flow-through system that utilized TSP radiotracer and that permitted manipulation of the velocity, flushing rate, and oxygen concentration of overlying water was ...

Energy Technology Data Exchange (ETDEWEB)

The ammoxidation of propane over VSb{sub y}O{sub x} catalysts (y=1, 2, 5) was investigated with respect to the role of different oxygen species in the selective and non selective reaction steps using transient experiments in the Temporal Analysis of Products (TAP) reactor. Only lattice oxygen is involved in the oxidation reactions. Using isotopic labelled oxygen it is shown that two different active sites exist on the surface. On site A, which can be reoxidized faster by gas phase oxygen compared to site B, mainly CO is formed. On site B CO{sub 2} and acrolein as well as NO and N{sub 2}O in the presence of ammonia in the feed gas are formed and reoxidation mainly occurs with bulk lattice oxygen. (orig.)

International Nuclear Information System (INIS)

Noninvasive and simplified methods for estimating regional cerebral blood flow (CBF) and regional partition coefficient (#lambda#) using the inhalation of stable xenon (Xe"s) and computed tomographic (CT) scanning are described. Thirty percent Xe"s in 70% oxygen was inhaled for 240 seconds and exhaled for 160 seconds during serial CT scanning without denitrogenation in 26 patients with cerebrovascular diseases and four volunteer controls. During the investigation, the end-tidal Xe"s concentration was continuously monitored with a thermoconductivity analyzer to determine the build-up range (A value) and build-up rate constant (K value) of the artery by the curve fitting method. Calculated A and K values were corrected by the following formulae reported previously: for patients aged 0-20 years, A_e = 0.75A_a + 2.15, K_e = 0.67K_a + 0.69; 21-40 years, A_e = 0.56A_a + 3.24, K_e = 0.38K_a + 1.12; 41-60 years, A_e = 0.91A_a + 1.95, K_e = 0.38K_a + ...

International Nuclear Information System (INIS)

Recently developed oxygen O18 method [K. Franzreb, J. Lorincik, P. Williams, Surf. Sci. 573 (2004) 291; R.C. Sobers, K. Franzreb, P. Williams, Appl. Surf. Sci. 231-232 (2004) 729; P. Williams, R.C. Sobers Jr., K. Franzreb, J. Lorincik, Appl. Surf. Sci. 252 (2006) 6429] is able to quantitatively determine the flux ratio of oxygen to matrix species at dynamical SIMS sputtering. This flux ratio can be directly related to the surface oxygen concentration at dynamical sputtering - an important parameter controlling the ionization yield of emitted species. It is argued that the oxygen O18 method is a worthy step forward in gathering relevant experimental data that might eventually lead to the understanding of oxygen enhancement mechanism in SIMS. A current status of understanding of the ionization processes in SIMS is briefly discussed in terms of non-adiabatic strongly velocity dependent ...

Energy Technology Data Exchange (ETDEWEB)

The potential hazard of landfill wastes was previously evaluated by examining the extraction procedures for individual waste, although various wastes were co-disposed of in actual landfills. This paper investigates the reduction of extraction-procedure toxicity by co-disposing various combinations of two wastes. When two wastes are mixed homogeneously, the extraction of heavy metals from the waste mixture is critically affected by the extract pH. Thus, co-disposal wastes will have a resultant pH between the pH values of its constituent. The lower the resultant pH, the lower the concentrations of heavy metals in the extract. When these wastes are extracted sequentially, the latter extracted waste has a stronger influence on the final concentration of heavy metals in the extract. Small-scale lysimeter experiments confirm ...

International Nuclear Information System (INIS)

The liquid-liquid extraction behavior of short-lived molybdenum and tungsten isotopes from HCl and HNO_3 as well as HF/HNO_3 acid media was studied using the #alpha#-benzoinoxime/chloroform system. The goal of the present experiments was to find an extraction system with a high selectivity for the group 6 elements in the periodic table which is suitable for the study the solution chemistry of seaborgium (Z = 106). It was found that Mo and W are both effectively extracted using #alpha#-benzoinoxime as an extractant and the maximum extraction yield is 100% and 94% for Mo and W, respectively. Ions of MO_2"2"+ (M = Mo, W) exist in HCl between the concentration range of 0.1-3 M and can be extracted quantitatively into the organic phase. The decrease of extraction yields at lower or higher acid concentration is due to the formation of anionic ...

Energy Technology Data Exchange (ETDEWEB)

We study the surface and interface roughness of a two-liquid film system using neutron reflectometry. The middle phase and bottom phase are extracted from a three-phase microemulsion containing 2 wt% non-ionic surfactant C{sub 10}E{sub 4}, 81 wt% D{sub 2}O and 17 wt% octane (C{sub 8}H{sub 18}). The system is formed by spreading a few drops of the middle phase of the microemulsion on the bottom phase of the microemulsion. The middle phase does not wet the bottom phase, but demixes to form a top octane-water mixture layer with a thickness of {proportional_to}580 A. The mean surface roughness of the system is found to be 7 A but the data are insensitive to interface roughness. An extended capillary wave model for a two-liquid-film system is derived to account for the coupling between the surface and interface. The dispersion relation yields two fundamental modes. In a calculation of mean-square roughness (left angle {zeta}{sup 2} right angle {sup ...

International Nuclear Information System (INIS)

An attempt is taken to explain anomalies in "9"2Mo(d, n)"9"3Tc, "9"2Mo(d, #alpha#)"9"0Nb, "9"4Mo(d, n)"9"5Tc, "9"8Mo(d, n)"9"9Tc, "9"8Mo(d, p)"9"9Mo, "9"8Mo(d, #alpha#)"9"6Nb, "1"0"0Mo(d, p)"1"0"1Mo and "1"0"0Mo(d, n)"1"0"1Tc reactions with input states having a one-particle nature. Thin films saturated with molybdenum isotopes at the approximately 1 mgxcm"-"2 surface density are used as targets. The targets are irradiated by the extracted cyclotron beam. The deuteron energy is 5-12 MeV. The reaction cross sections are determined by the activation analysis method. Quasi-stationary levels of the nucleus-deuteron system are calculated. Weak anomalies revealing in a smooth (d, #alpha#) reaction cross section on sup(92, 98)Mo nuclei, which do not necessarily correlate with anomalies in the (d, n) and (d, p) channels, are observed. The ground states of the (d, #alpha#) reaction products "9"0Nb and "9"6Nb have (8"+) and (6"+) spins, respec,.ively, ...

Science.gov (United States)

Surface wave tomography method based on analysis of ambient noise is widely used during the last decade. It is assumed that correlated component of noise is composed of surface waves generated by sources distributed over the Earth's surface more or less uniformly. In such a case the cross-correlation function (CCF) at two stations may be considered as the Green's function of surface wave. This function should be symmetric relatively to zero time. However analysis of CCF at the stations located at the East-European Platform shows that as a rule CCF is characterized with a strong asymmetry. Since "purered noise cannot be extracted from seismic records due to superposition of earthquake signals, the method for calculation of CCF includes amplitude normalization for suppression of earthquakes that reduces signals from earthquakes to a noise level. The parts of records containing waves from earthquakes are neglected because of their short duration. ...

International Nuclear Information System (INIS)

The decay of molybdenum-101 has been investigated using the three-parameter (#gamma#-#gamma#-t) coincidence system of HPGe-HPGe detectors. According to the off-line analysis, the decay scheme was modified. The positions of 221.80, 318.00, 377.90; 452.50, 515.42, 1011.05, and 1759.72 keV transitions have been arranged again, the transition positions of 104.70, 105.95, and 774.15 keV gamma rays have been assigned for the first time, the positions of 169.00, 590.91, 980.52, and 1431.68 keV transitions have been reconfirmed, and the 1508.01 keV gamma ray was observed simultaneously for the first time and its transition position has been assigned. The #beta#"- intensities and the values of log ft of most levels were calculated. Combining with the high-spin states observed by the in-beam #gamma#-ray spectroscopy of previous decay works, the structure of the excited positive/negative-parity yrast states of "1"0"1Tc is discussed using a projected shell model, and a band ...

International Nuclear Information System (INIS)

Purpose/Objective: At present, treatment verification between portal and reference images is performed based on manually-identified features by radiation oncologist, which is both time-consuming and potentially error-prone. There is a demand for the computerized verification procedure in clinical application. The purpose of this study is to develop a computerized portal verification scheme for pelvic treatment fields. Materials/Methods: The automated verification system involves image acquisition, image feature extraction, feature matching between reference and portal images and quantitative evaluation of patient setup. Electronic portal images with a matrix size of 256 x 256 and 12 bit gray levels were acquired using a liquid matrix electronic portal imaging device. Simulation images were acquired by digitizing simulation films using a TV camera into images with 256 x 256 matrix and 8 bit gray levels. Initially a Canny edge detector is applied to identify the ...

British Library Electronic Table of Contents (United Kingdom)

The extracts from kinnow peel, kinnow seeds, litchi pericarp, litchi seeds, grape seeds, and banana peel were screened for total phenolic content (TPC), trolox equivalent antioxidant capacity (TEAC), 1,1 diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity, as well as reducing power. Kinnow peel extract exhibited the highest reducing power, TEAC, and DPPH free radical scavenging activity, whereas, the phenolic content of 37.4 mg GAE/g-dw was highest for grape seed extract. Banana peel extract with a low TPC showed the lowest reducing power, TEAC as well as DPPH free radical scavenging activity among the fruit residue extracts examined in the present study. Correlation analysis between the reducing power and DPPH radical scavenging ability; reducing power and ABTS radical scavengin...

British Library Electronic Table of Contents (United Kingdom)

Summary Pectin was extracted from passion fruit peel using three different acids (citric, hydrochloric or nitric) at different temperatures (40-90 degreeC), pH (1.2-2.6) and extraction times (10-90 min), with and without skins using a 24 factorial design. Temperature, pH and extraction time had highly significant effects on the pectin yield. A central composite design with face centring was used to optimise the extraction process conditions for citric acid without skins. Pectin yields varied from 10% to 70%. The optimal conditions for maximisation of pectin yield were the use of citric acid at 80 degreeC and pH 1 with an extraction time of 10 min considering model extrapolation.

British Library Electronic Table of Contents (United Kingdom)

The physical and antioxidant properties of alginate biodegradable film incorporating white, red and extruded white ginseng extracts were investigated. No differences in moisture contents of all alginate film samples were noticeable (p>0.05) except those film samples incorporated without ginseng extract, which had the highest moisture content. The addition of ginseng extract to alginate film decreased tensile strength and elastic modulus (p<0.05) but increased the percent elongation at break. The presence of extracts did not significantly affect the water vapor permeability of the film samples. Alginate film containing extruded white ginseng extract at a barrel temperature of 130degreeC presented the highest (61.12%) free-radical scavenging activity against the 2,2-diphenyl-1-picryhydrazyl ...

CERN Document Server

Luminosity-driven channeling extraction has been observed for the first time in a 900 GeV study at the Fermilab Tevatron. This experiment, Fermilab E853, demonstrated that useful TeV level beams can be extracted from a superconducting accelerator during high luminosity collider operations without unduly affecting the background at the collider detectors. Multi-turn extraction was found to increase significantly the efficiency of the process. The beam extraction efficiency was about 25%. Studies of time dependent effects found that the turn-to-turn structure was governed mainly by accelerator beam dynamics. An investigation of a pre-scatterer using the accelerator flying wire system showed that a fiber could produce a significant extracted flux, consistent with expectations. Based on these results, it is feasible to construct a parasitic 5-10 MHz proton beam from the Tevatron ...

Energy Technology Data Exchange (ETDEWEB)

Acid mine drainage represents one of the most important environmental problem facing the mining industry. If the tailings contain sulphur, acid mine drainage will be generated as soon as the tailings are exposed to oxygen. In this paper, the authors discussed a technique for the storage of acid mine drainage generating tailings that delays and even eliminates the occurrence. It was suggested that tailings should be piled by incorporating, at regular intervals, compacted waste rock. Thermal convection and diffusion will prevent oxygen from reaching the tailings, and limit water circulation. The modelling of transfer processes (heat, water, oxygen) in a well known tailings dump, the Doyon Mine, was performed, and the results compared to the modelling where compacted waste rock had been incorporated at regular intervals. The results indicated that by remaining saturated, the layers acted as capillary barriers preventing ...

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The enhancement of positive secondary ion yields of silicon due to the presence of oxygen has been investigated quantitatively by low-energy (5 keV) oxygen implantation. Implantation and sputter profiling with 9 keV In/sup +/ were performed in the same ion microprobe instrument. Depth profiles of substrate and implanted oxygen atoms were measured for fluences ranging from 5x10/sup 15/ to 4x10/sup 16/ O-atoms/cm/sup 2/. The oxygen concentration, c(O), in the sample was deduced from the implanted fluence and the range distribution in the Gaussian approximation. It was found that the oxygen-enhanced Si/sup +/ intensity is proportional to c(O)sup(x) (with x=1.4) in the concentration regime, 1.5<=c(O)<=30 at%. The O/sup +/ intensity shows a similar dependence for c(O)> or approx.20 at.%.

Energy Technology Data Exchange (ETDEWEB)

To develop oxygen electrodes for rechargeable metal-air batteries, the electrochemical behaviour of gas-diffusion-type carbon electrodes loaded with Pr-Mn-Fe-based perovskite-type oxides was examined for the reduction and evolution of oxygen in 8 M KOH at 60 C. Among the oxides tested, Pr{sub 0.2}Ca{sub 0.8}Mn{sub 0.1}Fe{sub 0.9}O{sub 3} gave the highest electrode performances, e.g., current densities of 275 mA/cm{sup 2} (for oxygen reduction) and 225 mA/cm{sup 2} (for oxygen evolution) at -300 and +650 mV vs. Hg/HgO, respectively. The electrode performances were found to depend on both the catalytic activity of the oxides for H{sub 2}O{sub 2} decomposition reaction and the amounts of oxygen desorbed from the oxides. Furthermore, it was confirmed that the small zinc-air battery including the gas-diffusion-type electrode loaded with Pr{sub 0.2}Ca{sub 0.8}Mn{sub 0.1}Fe{sub 0.9}O{sub ...

Science.gov (United States)

This investigation will explore the effect that current timber extraction techniques have on plethadontid salamander populations in ... group selection, and two-age harvest. Broad scale timber extraction can d...

Science.gov (United States)

Information Extraction (IE) is an emerging NLP technology, whose function is to process unstructured, natural language text, to locate specific pieces of information, or facts, in the text, and to use these facts to fill a database. IE systems today are c...

UK PubMed Central (United Kingdom)

The stability of catalase, fumarase, and isocitrate lyase from deliberately broken organelles in crude extracts from endosperm tissue of castor bean seedlings has been examined. These enzymes are relatively...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe exploitation of information extraction (IE), a technology aiming to provide instances of structured representations from free-form text, has been rapidly growing within...Full Text Available

UK PubMed Central (United Kingdom)

Orthosiphon stamineus as medicinal plant is commonly used in Malaysia for treatment of hepatitis and jaundice; in this study, the ethanol extracts were applied to evaluate the...Full Text Available

International Nuclear Information System (INIS)

The author demonstrates through a specific example that it is possible to extract rotational energy from a Kerr source (in principle, of arbitrary size but not turned black) through a reversible process by suitably injecting tachyons. (Auth.).

UK PubMed Central (United Kingdom)

A nucleic acid extraction system that can handle small numbers of specimens with a short test turnaround time and short hands-on time is desirable for emergent testing. We performed a comparative validation...Full Text Available

UK PubMed Central (United Kingdom)

Objective:The main objective of this work was to study the antipyretic and antibacterial activity of C. erectus (Buch.-Ham.) Verdcourt leaf extract in an...Full Text Available

UK PubMed Central (United Kingdom)

An anion-exchange column technique for extraction of antibiotics from serum proteins has been developed for use in the assay of cephapirin, cefotaxime, and cefoxitin by high-pressure liquid chromatography....Full Text Available

Science.gov (United States)

One of the NASA research activities was to identify, characterize, and simulate a series of technologies that could be used for hydrogen production at NASA Kennedy Space Center (KSC) using locally available sources. This project examined the production of hydrogen from solar energy. To produce hydrogen by water splitting, the operating voltage of conventional photovoltaic (PV) cells cannot supply the overvoltage required. Thus, the objective of this project was to research and develop photoelectrochemical (PEC) cells that can supply the required voltage for water splitting by constructing a multiple bandgap tandem PV cell and a photocatalyst that can be activated by infrared (IR) photons transmitted through the PV cell. The proposed concept is different from conventional PEC water splitting by using multiple band gap combinations. The advantages for this PEC cell concept is that the PV cells are not in contact with the electrolyte solution, thus reducing the problems of corrosion and ...

Energy Technology Data Exchange (ETDEWEB)

X-ray crystal structures of L-3,4-dihydroxy-2-butanone-4-phosphate synthase from Magnaporthe grisea are reported for the E-SO{sub 4}{sup 2-}, E-{sub 4}{sup 2-}-Mg{sup 2+}, E-SO{sub 4}{sup 2-}-Mn{sup 2+}, E-SO{sub 4}{sup 2-}-Mn{sup 2+}-glycerol, and E-SO{sub 4}{sup 2-}-Zn{sup 2+} complexes with resolutions that extend to 1.55, 0.98, 1.60, 1.16, and 1.00 {angstrom}, respectively. Active-site residues of the homodimer are fully defined. The structures were used to model the substrate ribulose 5-phosphate in the active site with the phosphate group anchored at the sulfate site and the placement of the ribulose group guided by the glycerol site. The model includes two Mg{sup 2+} cations that bind to the oxygen substituents of the C2, C3, C4, and phosphate groups of the substrate, the side chains of Glu37 and His153, and water molecules. The position of the metal cofactors and the substrate's phosphate group are further stabilized by an extensive hydrogen-bond ...

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The aim of this work was to develop a method to distinguish between different ion formation processes and to determine the influence of these processes on the total number of detected monatomic ions of a certain element. A vector/matrix-formalism was developed, which describes the physical processes of sputtering, ion formation, mass separation and detection in laser-SNMS. In the framework of the method developed, based on this theoretic formalism, changes in the secondary flux contribution of the respective element were observed by comparing the detected monatomic ion yield obtained in specifically aligned (SIMS and) laser-SNMS experiments. The yields resulting from these experiments were used to calculate characteristic numbers to compare the flux composition from different surfaces. The potential of the method was demonstrated for the elements boron, iron and gadolinium by investigating the changes in the flux composition of secondary particles sputtered from ...

Energy Technology Data Exchange (ETDEWEB)

A noninvasive, simplified method using inhalation of stable xenon (Xe{sup s}) and computed tomographic (CT) scanning to estimate regional cerebral blood flow (rCBF) and regional partition coefficient (r{lambda}) is described. Twenty-four patients with cerebrovascular occlusive disease and six volunteer controls inhaled 30% Xe{sup s} and 70% oxygen for 180 seconds and exhaled for 144 seconds during serial CT scanning without denitrogenation. The end-tidal Xe{sup s} concentration was continuously monitored with a thermoconductivity analyzer to determine the build-up range (A value) and build-up rate constant (K value) for arteries with the curve fitting method. The time-CT number (Hounsfield unit) curve for cerebral tissue during the Xe{sup s} washin and washout phases was used to calculate r{lambda} and rCBF using least squares curve fitting analysis. The resultant r{lambda} and rCBF map demonstrated a reliable distribution between the gray and ...

Energy Technology Data Exchange (ETDEWEB)

Chemical looping combustion (CLC) is a novel technology where CO{sub 2} is inherently separated during combustion. Due to the existence of sulfur contaminants in the fossil fuels, the gaseous products of sulfur species and the interaction of sulfur contaminants with oxygen carrier are a big concern in the CLC practice. The reactivity of NiO/Al{sub 2}O{sub 3} oxygen carrier reduction with a gas mixture of CO/H{sub 2} and H{sub 2}S is investigated by means of a thermogravimetric analyzer (TGA) and Fourier Transform Infrared spectrum analyzer in this study. An X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscope (SEM) are used to evaluate the phase characterization of reacted oxygen carrier, and the formation mechanisms of the gaseous products of sulfur species are elucidated in the process of chemical looping combustion with a gaseous fuel containing hydrogen sulfide. The results ...

Energy Technology Data Exchange (ETDEWEB)

The oxidation of Cr(III) hydroxides, mixed Fe(III)-Cr(III) hydroxides, and specimens of spinel phases NiCr2O4 and Fe(Cr,Fe)2O4 have been investigated in alkaline suspensions under the action of air and pure oxygen (1-3 atm). The rate of reaction increases with increasing alkali concentration, temperature, and oxygen pressure. Pu(IV) fixed on chromium hydroxides is not oxidized by oxygen under these conditions but is retained in the precipitate.

Energy Technology Data Exchange (ETDEWEB)

Green River oil shale was air oxidized at subretorting temperatures. Off gases consisting of nitrogen, oxygen, carbon monoxide, carbon dioxide, and water were monitored and quantitatively determined. A mathematical model of the oxidation reactions based on a shrinking core model has been developed. This model incorporates the chemical reaction of oxygen and the organic material in the oil shale as well as the diffusivity of the oxygen into the shale particle. Diffusivity appears to be rate limiting for the oxidation. Arrhenius type equations, which include a term for oil shale grade, have been derived for both the chemical reaction and the diffusivity.

KoreaScience (Korea)

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International Nuclear Information System (INIS)

... chemical radiation effects decomposition extraction columns gamma radiation

KoreaScience (Korea)

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International Nuclear Information System (INIS)

... carrier-free isotopes chemical preparation gamma spectra isotope production

Energy Technology Data Exchange (ETDEWEB)

The nature and properties of inorganic /sup 211/At-species formed in aqueous solutions under alkaline, neutral, acidic and oxidative conditions are studied through extraction of At with a variety of organic solvents, followed by the determination of the chromatographic, re-extraction and interaction behaviour of the extracted activity. It is concluded from the Rsub(f) values (on SiO/sub 2/) and the different affinities for a large amount of additives, that the extracted activity - formerly denoted as At-zero - exists of AtX compounds that may form AtXLsub(u) complexes, depending on the kind of solvent (L) used.

KoreaScience (Korea)

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Science.gov (United States)

... study is to collect data in previously harvested timber stands to quantify the differences in herbaceous diversity ... ...

KoreaScience (Korea)

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KoreaScience (Korea)

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UK PubMed Central (United Kingdom)

Mitochondrial superoxide production is an important source of reactive oxygen species in cells, and may cause or contribute to ageing and the diseases of ageing. Seven major sites of superoxide...Full Text Available

UK PubMed Central (United Kingdom)

Dogs challenged with toxic doses of methylsalicylate developed acute myocardiopathy. Metabolic manifestations of uncoupling of oxidative phosphorylation by methylsalicylate (MS) were observed. Oxygen...Full Text Available

Science.gov (United States)

cellulose casing material made by Food Products Division,. Union Carbide Corporation. tion of the anode from oxygen generated at the charging electrode. ...