Identification of oxidation states of ultra-trace elements by radiation detection
International Nuclear Information System (INIS)
The determination of the oxidation state of ultra-trace elements in the environment, especially in the case of actinides, is of importance in many ways. Speciation techniques using radiation may comprise methods based on the detection of the nuclear and atomic radiations emitted in radioactive decay or methods using external sources of excitation. In the former instance, information can be obtained from the energy and intensity of radiation, but at present the partition method is still the most commonly used, although its reliability is questionable. Excitation with intense laser beams, as is currently being used for trace element analysis in photoacoustic and thermal lensing spectroscopic techniques, could conceivably be applied under suitable conditions to ultra-trace elements with a sensitivity approaching that of the radiochemical methods.
1989-11-01
Energy Technology Data Exchange (ETDEWEB)
The use of high-performance ion exchangers allows a trace-matrix-separation (SMT) directly followed by an ion chromatographic (IC) separation of the analytes. Based on the principles described in Part 1, a combined procedure IC-SMT-IC for metallic impurities in Mo and W is presented. Up to 12 metal traces (Fe, Cu, Pb, Zn, Ni, Co, Cd, Ca, Mn, Sr, Mg and Ba) can be determined in one run with 35 min. A special method for traces of U and Th is also given. Detection limits are typically 10-100 ng g{sup -1} in the metal sample. (author). 14 refs.; 10 figs.; 6 tabs.
1992-01-31
Energy Technology Data Exchange (ETDEWEB)
It is reported about the adsorptive stripping voltammetric determination of uranium, antimony, tin, vanadium and molybdenum using chloranilic acid as complex forming reagent. The determination limits are in the l{sup 1}-range. (orig.) [Deutsch] Es wird ueber die Bestimmung von Uran, Antimon, Zinn, Vanadium und Molybdaen durch Adsorptions-Stripping-Voltammetrie mit Chloranilsaeure als Komplexbildner berichtet. Die Bestimmungsgrenzen liegen im ng l{sup -1} Bereich. (orig.)
1996-12-01
British Library Electronic Table of Contents (United Kingdom)
An extremely sensitive stripping voltammetric procedure for ultra-trace determination of iridium(III) is reported. The method is based on the interfacial accumulation of the iridium(III)-CTAB complex onto the glassy carbon electrode, followed by the catalytic reduction of the adsorbed complex in the presence of bromate. 0.3molL^-^1 acetate buffer pH 4.7+6.9x10^-^2molL^-^1 NaBrO3+2.7x10^-^5molL^-^1 cetyltrimethylammonium bromide (CTAB)+0.2molL^-^1 KCl was employed as the supporting electrolyte. The analytical procedure was verified by the analysis of the standard reference materials: Sea Water BCR-CRM 403 and Fresh Water NIST-SRM 1643d. The accuracy, expressed as relative error e%, was satisfactory, being lower than 6%, while precision as repeatability, expressed as relative standard deviat...
2011-01-01
H_2 emission arises outside photodissociation regions in ultra-luminous infrared galaxies
Ultra-luminous infrared galaxies are among the most luminous objects in the local universe and are thought to be powered by intense star formation. It has been shown that in these objects the rotational spectral lines of molecular hydrogen observed at mid-infrared wavelengths are not affected by dust obscuration, leaving unresolved the source of excitation of this emission. Here I report an analysis of archival Spitzer Space Telescope data on ultra-luminous infrared galaxies and demonstrate that star formation regions are buried inside optically thick clouds of gas and dust, so that dust obscuration affects star-formation indicators but not molecular hydrogen. I thereby establish that the emission of H_2 is not co-spatial with the buried starburst activity and originates outside the obscured regions. This is rather surprising in light of the standard view that H_2 emission is directly associated with star-formation ...
2010-01-01
Analysis of Automotive Paints using Pyrolysis-Gas Chromatography
Energy Technology Data Exchange (ETDEWEB)
The automotive paints could be generally differentiated by color, layer sequence and chemistry of the paint layers comprising each of the topcoat and the primer system. The successful identification of hit-and-run a and traffic accidental vehicles from evidential paint fragments is greatly facilitated with a comprehensive laboratory collection of reference paint samples and the technique for direct analysis without sample preparation. The Pyrolysis-Gas Chromatography(PGC) is a precise and reliable method for performing both quantitative and qualitative analysis of polymeric materials and forensic samples. Our Forensic Laboratory is conducting the examination and identification of 73 reference paint samples; 4 colors of each domestic automotive make that is poplar in Korea, by Curie Point Pyrolyzer(JHP-3) and GC with capillary column(ultra alloy-5). This method can be used not only to compare paint ...
2000-02-01
Determination of trace amounts of thallium and lead by photon activation analysis
International Nuclear Information System (INIS)
... activation analysis lead lead 203 lead 204 microanalysis nuclear reactions
Determination of Proper Peaking Time for Ultra Lege detector at Medium Energies
International Nuclear Information System (INIS)
Reducing count losses and pile-up pulse effects in quantitative and qualitative analysis is necessary for accuracy of analysis. Therefore, the optimum peaking time for particular detector systems is important. For this purpose, pure Se and Zn elements were excited by 59.5 keV ?-rays from a 50 mCi 241Am annular radioactive source in this study. The characteristic x-rays emitted from pure Se and Zn elements were detected by using an ultra low energy Ge (Ultra-LEGe) detector connecting Tennelec TC 244 spectroscopy amplifier at different peaking time modes. Overall pulse widths were determined by HM 203-7 oscilloscope connecting amplifier. The proper peaking time for ultra low energy germanium detector (Ultra-LEGe) is determined about 4 ?s.
2008-08-25
PIXE analysis of trace elements in relation to chlorophyll concentration in Plantago ovata Forsk
Energy Technology Data Exchange (ETDEWEB)
Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.
2010-03-15
Ionospheric Modeling and Propagation Analysis.
... these features and yields results which are two orders of magnitude faster than those available using conventional numerical ray tracing techniques ...
1980-04-01
Trace metal concentrations in estuaries and coastal regions
Energy Technology Data Exchange (ETDEWEB)
Estuaries and coastal regions are highly variable in the physical and hydrographic conditions. As a result of heavy urbanization and industrialization of the head waters of most estuaries, there are substantial localized inputs of contaminants to the estuary. These factors combined with the flushing characteristics of individual estuaries to create relatively unique features that result in variation in the typical levels of trace metals for these systems. This makes intercomparison of the estuaries difficult. Comparability among estuaries becomes even more difficult when metals analyses are conducted without proper control of field and laboratory contamination, now firmly established in the trace metal analytical literature as a prerequisite for reliable marine trace metals analysis. This paper compares the concentrations of selected trace metal (Ag, Cd, Cu, Ni, Pb, and Zn) ...
1994-12-31
A Software System for Data Analysis in Automated DNA?Sequencing
UK PubMed Central (United Kingdom)
Software for gel image analysis and base-calling in fluorescence-based sequencing consisting of two primary programs, BaseFinder and GelImager, is described. BaseFinder is a framework for trace processing,...Full Text Available
1998-06-01
A mobile remote sensing laboratory for water vapor, trace gas, aerosol, and wind speed measurements
Energy Technology Data Exchange (ETDEWEB)
The Lawrence Livermore National Laboratory has developed a mobile field laboratory for remote measurement of atmospheric processes and observables that are important in global climate change, dispersal of hazardous materials, and atmospheric pollution. Specific observables of interest are water vapor, trace gases, aerosol size and density, wind, and temperature. The goal is to study atmospheric processes continuously for extended periods in remote field locations. This laboratory has just reached field ready status with sensors for aerosol and trace gas measurement based on established techniques. A development program is underway to enhance the sensor suite with several new techniques and instruments that are expected to significantly extend the state of the art in remote trace gas analysis. The new sensors will be incorporated into the lab during the next two years.
1993-03-19
International Nuclear Information System (INIS)
A simple and rapid laser fluorometric determination of trace and ultra trace level of uranium in a wide variety of low uranium content materials like soil, basic and ultra basic rocks, plant ash, coal fly ash and red mud samples is described. Interference studies of some common major, minor and trace elements likely to be present in different geological materials on uranium fluorescence are studied using different fluorescence enhancing reagents like sodium pyrophosphate, orthophosphoric acid, penta sodium tri-polyphosphate and sodium hexametaphosphate. The accurate determination of very low uranium content samples which are rich in iron, manganese and calcium, is possible only after the selective separation of uranium. Conditions suitable for the quantitative single step extraction of 25 ng to 20 #mu#g uranium with tri-n-octylphosphine oxide and single step quantitative stripping ...
1999-10-01
Measurement of time of travel in streams by dye tracing
Energy Technology Data Exchange (ETDEWEB)
The US Geological survey is active in measuring time of travel in streams using dye tracers. This manual describes methods of measuring time of travel of water and waterborne solutes by dye tracing. The fluorescent dyes, measuring equipment used, and field and laboratory procedures are also described. Methods of analysis and presentation to illustrate time of travel of streams are provided.
1989-01-01
Determination of heavy metals in welders' working environment using nuclear analytical methods
International Nuclear Information System (INIS)
Technological processes of welding are significant sources of pollution in the working area. Evaluation of chemical quality of working area was made by means of radionuclide x-ray fluorescence analysis and activation analysis with fast neutrons. Welding aerosols were sampled by filtration method on Synpor 4 membrane ultra-filters. For selected types of welding filter metals, determination of heavy metals in aerosols was performed. (author).
1985-01-01
Determination of heavy metals in welders' working environment using nuclear analytical methods
Energy Technology Data Exchange (ETDEWEB)
Technological processes of welding are significant sources of pollution in the working area. Evaluation of chemical quality of working area was made by means of radionuclide x-ray fluorescence analysis and activation analysis with fast neutrons. Welding aerosols were sampled by filtration method on Synpor 4 membrane ultra-filters. For selected types of welding filter metals, determination of heavy metals in aerosols was performed.
1985-01-03
Synthesis of deuterated eicosanoids
Energy Technology Data Exchange (ETDEWEB)
Deuterated lipoxygenase and cyclooxygenase derivatives of eicosatetraenoic acid (arachidonic acid) and their metabolites are indispensable tools for organic trace analysis, biomedical studies, and mechanistic investigations on the corresponding endogenous (unlabelled) eicosanoids. Methods for the preparation of deuterated eicosanoids are reviewed.
1986-03-01
UK PubMed Central (United Kingdom)
Randomly amplified polymorphic DNA (RAPD) analysis and the PCR assay were used in combination with dilution plating on a semiselective medium to detect and enumerate propagules of Trichoderma...Full Text Available
1999-12-01
International Nuclear Information System (INIS)
This paper discusses essentially the role of WDXRFS based multi element data in uranium exploration, with special reference to India. The state of art MagiX-PRO WDXRFS with 4 kW end window x-ray tubes has been used in the present study as an indispensable geo-analytical tool for the analysis of major and selected trace elements at ppm to percentage level, with high precision and relatively better accuracy
2010-10-01
International Nuclear Information System (INIS)
Coal is the most abundant available fossil fuel in Australia and provides a substantial part of energy needs. It is used for power generation, to supply energy to industry as well as for domestic requirements. Analysis of trace elements (the elements present in coal in ppm/ppb level) during combustion of coal in very important. Trace elements, like heavy metals such as arsenic, selenium, and chromium etc. are hazardous to the environment and some of them have carcinogenic potency. In the near future more stringent limits may be proposed for such elements generated from combustion process, such as coal combustion in power plants. Hence analysis and assessment of the emissions of these elements is essential at this stage. The first step towards reducing any impacts of trace elements is to have accurate quantitative analysis. Analysis of coal, ...
2005-11-20
Challenges in environmental radiological surveillance around nuclear facilities
International Nuclear Information System (INIS)
To accomplish the environmental radiological surveillance need of India's ambitious nuclear power programme, Health Physics Division is infusing new technologies and improved analytical techniques for day to day measurements of various radionuclides in different environmental matrices. It is essential to have techniques for measuring the concentration of radionuclides just above the background level since the discharges from the nuclear facilities are very low i.e. in the range of 5-10% of the prescribed discharge limits by the regulatory bodies. In view of developing ultra-sensitive techniques, the aim of ongoing programmes of the division is to meet the challenges of measuring ultra trace level of radioactivity by adopting state of art new instrumentation and improved sample processing techniques. This will allow us to measure the lowest level of radioactivity (3H, 90Sr, 137Cs, 239+240Pu, etc.) in the environment and ...
2007-06-05
Trace Elements in Human Myocardial Infarction Determined by Neutron Activation Analysis
International Nuclear Information System (INIS)
By means of neutron activation analysis, injured and adjacent uninjured human heart tissue from 12 autopsy cases with myocardial infarction are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent y-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, Zn and W. In the injured tissue compared to the uninjured, calculation on a wet weight basis showed a decrease in Co, Cs, K, Mo, P, Rb and Zn, and an increase in Br, Ca, Ce, La, Na, Sb and Sm. The differences in Ca, La, Mo, P and Zn are dependent on the age of the myocardial infarction, and the regression lines for these elements are given. The concentration of the trace elements in uninjured tissue from infarcted hearts is ...
1965-01-01
Contribution to the in vitro multielement X-ray fluorescence analysis of human soft tissues
International Nuclear Information System (INIS)
Determination of Mn, Fe, Ni, Cu, Zn, and Pb in human soft tissues by radionuclide X-ray fluorescence analysis (using "2"3"8Pu and "1"0"9Cd sources) is described. The results of multielement XRS analysis of selected human tissues are tabulated. They are in good agreement with the literature data. It is concluded that X-ray fluorescence technique is a suitable method for trace element determination. (author).
1986-11-01
UK PubMed Central (United Kingdom)
The interpretation of solution hydrodynamic data in terms of macromolecular structural parameters is not a straightforward task. Over the years, several approaches have been developed to cope...Full Text Available
2010-02-01
Separation of rubidium from irradiated aluminum-encapsulated uranium
International Nuclear Information System (INIS)
A procedure was developed for separating rubidium from irradiated aluminum encapsulated uranium. The separations procedure produces a final ultra-high purity RbCl product for subsequent high performance mass spectrometric analysis. The procedure involves first removing most of the macro-components and fission products by strong base anion exchange using, first, concentrated HCl, then oxalic acid media and second, selectively separating rubidium from alkaline-earth ions and other alkali-metal ions, including cesium, using Bio-Rex-40 cation-exchange resin. The resultant RbCl is then put through a final vacuum sublimation step. Ultra-pure reagents and specially clean glassware are used throughout the procedure to minimize contamination by naturally-occurring rubidium.
1993-05-01
Separation of rubidium from irradiated aluminum-encapsulated uranium
Energy Technology Data Exchange (ETDEWEB)
A procedure was developed for separating rubidium from irradiated aluminum encapsulated uranium. The separations procedure produces a final ultra-high purity RbCl product for subsequent high performance mass spectrometric analysis. The procedure involves first removing most of the macro-components and fission products by strong base anion exchange using, first, concentrated HCl, then oxalic acid media and second, selectively separating rubidium from alkaline-earth ions and other alkali-metal ions, including cesium, using Bio-Rex-40 cation-exchange resin. The resultant RbCl is then put through a final vacuum sublimation step. Ultra-pure reagents and specially clean glassware are used throughout the procedure to minimize contamination by naturally-occurring rubidium.
1982-01-01
Production and characterization of ultrafine WC powders
International Nuclear Information System (INIS)
The conventional Calzination-Reduction-Carburization (CRC) process offers the potential to manufacture commercial WC powders with median SEM grain sizes below 0.5 pm (ultra fine grades). Strict process control and a high degree of automation have led to increased powder uniformity and high lot-to-lot reliability. The high potential and flexibility of the CRC process is shown by the development of tailor made WC powders with regard to subsequent alloy manufacturing. R and D powders have successfully been processed in full-scale units exhibiting SEM grain sizes of 0.15 - 0.20 pm. This paper discusses the powder characteristics of various ultra fine WC powder grades, stemming from the conventional CRC process. Analytical characterization include also field-emission SEM, bright field TEM, EDX analysis and XRD-line broadening. (author)
2001-05-01
Neutron activation analysis of trace elements in Japanese hormesis cosmetics
International Nuclear Information System (INIS)
In Japan, cosmetics claiming hormesis effect are available through Internet. Although these cosmetics show the contents, they never mention the minor elements and radioactive sources. The existence of radioisotopes, however, was observed by measurements of the gamma-rays with a HPGe detector. In this study, in order to clarify the contents of trace elements, the hormesis cosmetics including radioactive sources were analyzed using INAA, PGAA and NAA with multiple gamma-ray detection (NAAMG). Nineteen elements were analyzed quantitatively in hormesis cosmetics by INAA, PGAA and NAAMG and 16 elements were detected qualitatively by SEM-EPMA. (author)
2008-12-01
Determination of uranium and thorium concentrations in integrated circuit packaging materials
International Nuclear Information System (INIS)
The purpose of the present research is to find a suitable technique to measure trace amounts of uranium and thorium and to determine the surface #alpha#-flux in silicon compound (SiO) used for fabrication of integrated circuit packaging materials. Among several commonly-used detecting techniques, it was found that neutron activation analysis (NAA) was most promising. The results from NAA show a large difference in uranium and thorium concentrations when cadmium and boron carbide shields are used, whereas #alpha#-flux measurements show a low #alpha#-activity, which corresponds to the trace amounts of uranium and thorium expected to be present in these materials. (author) 13 refs.; 6 figs.
Trace element intake and status of Italian subjects living in the Gubbi area
International Nuclear Information System (INIS)
Daily intakes of certain trace elements (Pb, Cd, Ni, Hg, and Cr) were assessed using dietary history and weighed record methods and concurrent chemical analysis (CA) of duplicate portions, along with blood levels, in a group (21 M, 23 F) of inhabitants of the Gubbio area (Belvedere, Biscina Scritto). The evaluation of only intake of trace elements was accomplished in 40 subjects (20 M, 20 F) 1 year later. In both surveys, trace element intakes were generally lower than the potential tolerable weekly intake. However, daily intakes of Pb, Cd, Ni, Hg, and Cr were higher in men compared to women in both surveys (P<0.05). In fact, intakes at the 50th percentile were greater in men by approximately 75% for Pb, 91% for Cd, 20% for Ni, 45% fo Hg, and 29% for Cr in the first survey. In the second survey, percentage differences for Pb, Cd, Ni, and Cr were about 12%, 28%, 26%, and 26%, respectively. Blood ...
2003-02-01
SLAROM-UF: Ultra fine group cell calculation code for fast reactor
International Nuclear Information System (INIS)
A cell calculation code SLAROM-UF was developed to improve calculation accuracy of effective cross sections for various fast reactor types. SLAROM-UF has a capability to calculate effective cross sections in ultra fine groups of about 100,000 below 50keV and in fine groups above the energy (maximum 900 groups). Resonance interaction among the fuel, the coolant, and the structure materials can be treated accurately even in a heterogeneous cell structure. Temperature can be set up freely in a cell by the ultra fine group calculation. Improvement in nuclear characteristics was observed in the analysis of JUPITER critical experiment, as 0.1% for criticality, 4% for sodium void reactivity, several % for radial reaction rate distribution, when SLAROM-UF was used instead of the typical cell calculation code. The effect of the ultra fine group calculation is remarkable in the non-leakage term of sodium void ...
Tolerance analysis of a phase space beam analyzer
The phase space beam analyzer is a measurement instrument that is applied in laser technology to perform analyses of the spatial and angular distribution of rays. We are interested in this instrument as a means to characterize non-coherent light sources. In this context, a closer look at the tolerances of this optical instrument was considered useful. Having a so-called quadrupole lens as a key element, the phase space beam analyzer is a device that features anamorphic optical properties. To describe these anamorphic properties, recurrence was made to a description by extended ray-transfer matrices. This formalism allows for an analysis of the alignment tolerances of the phase space beam analyzer and facilitates a study of the sensitivities of the instrument. The analysis is complemented using numerical ray tracing.
2007-09-01
The use of lead isotopic abundances in trace uranium samples for nuclear forensics analysis
International Nuclear Information System (INIS)
Secondary ion mass spectrometry (SIMS), secondary electron microscopy (SEM) and X-ray analysis have been applied to the measurement of U-bearing particles with the intent of gleaning information concerning their history and/or origin. The lead isotopic abundances are definitive indicators that U-bearing particles have come from an ore-body, even if they have undergone chemical processing. SEM images and X-ray analysis can add further information to the study that may allude to the extent of chemical processing. The presence of 'common' lead that does not exhibit a radiogenic signature is clear evidence of anthropogenic origin. (author)
2010-06-01
Coverage and large scale anisotropies estimation methods for the Pierre Auger Observatory
Energy Technology Data Exchange (ETDEWEB)
When searching for anisotropies in the arrival directions of Ultra High Energy Cosmic Rays, one must estimate the number of events expected in each direction of the sky in the case of a perfect isotropy. We present in this article a new method, developed for the Auger Observatory, based on a smooth estimate of the zenith angle distribution obtained from the data itself (which is essentially unchanged in the case of the presence of a large scale anisotropy pattern). We also study the sensitivity of several methods to detect large-scale anisotropies in the cosmic ray arrival direction distribution : Rayleigh analysis, dipole fitting and angular power spectrum estimation.
2005-07-01
Energy Technology Data Exchange (ETDEWEB)
This short paper (abstract) describes the characteristics and performances of prototypes of ultra-thin lithium micro-batteries (thickness < 0.2 mm) which can be incorporated into microelectronic circuits. (J.S.)
1996-12-31
Energy Technology Data Exchange (ETDEWEB)
In the case where sources and receivers are not distributed on a 2-D plane, seismic tomography inversion was studied. In tomography experiments, the existing wells are generally used. In such case, sources and receivers are frequently not distributed on a 2-D plane. The 2.5-D analysis method including 2-D structure and 3-D ray-tracing was thus developed. This method is featured by less memory necessary for ray-tracing calculation, and the same algorithm for velocity determination as 2-D analysis method. In previous methods, since analysis is generally carried out by projecting sources and receivers on a certain assumed 2-D plane, it can derive correct results in the case of constant velocity and straight ray, however, in the other case, it derives incorrect results. Application of 3-D tomography requires a large amount of memory, and falls into poor convergence because of various ...
1996-10-01
International Nuclear Information System (INIS)
Determination of Cr, Fe, Cu, Zn and Pb in drinking water preconcentrated on a chelating ion exchanger of Czechoslovak production is described. The analytical system consisted of a radionuclide source "2"3"8Pu, a Si/Li semiconductor detector and a multichannel analyzer. Results are compared with trehshold limit values recommended for drinking water. (author) 9 refs.; 2 figs.
1992-04-01
UK PubMed Central (United Kingdom)
Chemical contamination can be one of the more common problems encountered when performing trace-level analysis regardless of the analytical technique. Minimizing or eliminating background interferences...Full Text Available
2008-05-01
Determination of Mg, Al, Si, Cl and K in some medicinal plants by NAA and REA methods
Energy Technology Data Exchange (ETDEWEB)
Trace elements have been determined in biological samples including pepperwort, thyme, plantain, blessed thistle and common comfrey as well as cabbage leaves and milk powder. Concentrations of Al, Si, and Cl have been determined by fast neutron activation analysis while, in the case of Mg-, K, and Cl the X-ray fluorescence method was used.
1982-07-26
Ultra High Strength Beta Titanium Alloy for Fasteners.
... Accession Number : ADD151811. Title : Ultra High Strength Beta Titanium Alloy for Fasteners. Descriptive Note : Journal article,. ...
Estimation of essential and trace elements in some medicinal plants by PIXE and PIGE techniques
Energy Technology Data Exchange (ETDEWEB)
Proton induced X-ray emission (PIXE) and proton induced {gamma}-ray emission (PIGE) techniques are employed for the determination of essential and trace elements in some commonly used medicinal plants of north east India. Light elements such as Na, Mg, Al and P are determined by PIGE while medium Z elements such as K, Ca, Mn, Fe, Cu, Zn, Rb and Sr are determined by PIXE. Analysis is performed on pellets (thick targets) prepared using powders of the specimens which, in turn, are obtained following a series of processing steps. Plant based biological certified reference materials (CRMs) served as standards for quantification. These elements are found to be present in varying concentrations in the studied plants, with the contents of Mn and Zn being notably large in certain specimens. Medicinal properties possessed by these plants have been correlated with their elemental distribution.
2008-04-15
Studies of ultra-low energy electron-molecule collisions using very-high-n Rydberg atoms
International Nuclear Information System (INIS)
Potassium atoms in selected high-lying np Rydberg states (80 #<=# n #<=# 400) are being used as a tool to examine electron-polar molecule collisions at ultra-low energies (#approx#80 #mu#eV - 1 meV). This energy regime has not been investigated previously and is of interest because the corresponding electron de Broglie wavelength is large, #approx#1300 - 330 Angstrom, and because the collision time is comparable to the period of molecular rotation. A variety of target molecules has been studied, including simple rotors such as HF, and more complex species such as NH_3, CH_3I, CH_2Br_2 and C_6H_5NO_2. These targets encompass a range of dipole moments and rotational behavior, but analysis of the data shows that in each case the cross section #sigma#(#epsilon#) for rotationally-inelastic electron-polar molecule scattering varies approximately as 1/#epsilon# where #epsilon# is the electron energy. Such threshold behavior is not predicted by ...
1993-05-16
Energy Technology Data Exchange (ETDEWEB)
In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance-voltage measurement. The analysis of capacitance-voltage characteristics demonstrated that ...
2007-06-04
International Nuclear Information System (INIS)
In this work, the silicon oxynitride layer was studied as a tunneling layer for non-volatile memory application by fabricating low temperature polysilicon thin film transistors on glass. Silicon wafers were oxynitrided by only nitrous oxide plasma under different radio frequency powers and plasma treatment times. Plasma oxynitridation was performed in RF plasma using inductively coupled plasma chemical vapor deposition. The X-ray energy dispersive spectroscopy was employed to analyze the atomic concentration ratio of nitrogen/oxygen in oxynitride layer. The oxynitrided layer formed under radio frequency power of 150 W and substrate temperature of 623 K was found to contain the atomic concentration ratio of nitrogen/oxygen as high as 1.57. The advantage of high nitrogen concentration in silicon oxide layer formed by using nitrous oxide plasma was investigated by capacitance-voltage measurement. The analysis of capacitance-voltage characteristics demonstrated that ...
2007-06-04
Energy Technology Data Exchange (ETDEWEB)
In this work we present an ultra-low temperature method for the oxidation of an amorphous silicon-carbide-nitride (SiCN) material. The SiCN is deposited on silicon substrates by plasma enhanced chemical vapor deposition using CH{sub 4}, SiH{sub 4}, and N{sub 2} chemistry. The physical and chemical properties are characterized for the as-deposited SiCN and post-oxidized films are discussed. The SiCN film is exposed to oxygen plasma, where it undergoes a chemical transformation into a binary SiO{sub 2} material system. A 1.7 nm/min oxidation rate is typical for this process and compares favorably to oxidation methods utilizing much higher temperatures. The substrate temperature remains extremely low throughout the oxidation process, T{sub s} < 200 deg. C. Changes in film stress, optical constants, film thickness, surface roughness, and film density are measured. Chemical analysis by X-ray photoelectron spectroscopy is reported for both the ...
2008-01-30
Energy Technology Data Exchange (ETDEWEB)
The object of this research is the evaluation of the performance of ultra high speed relays (UHSR's) used for protection of a-c transmission lines. For purposes of this report, these are relays whose response time is less than a quarter of a cycle of the 60 Hz wave (i.e. 4.167 ms.). To identify relaying schemes that may comply with this definition, a literature survey was undertaken. The selected relays were studied in detail and modeled on a digital computer. A theoretical description of these relays is presented. Records of real transient data as well as of simulated data were used as input to the digital models of relays. The real data were recorded by means of monitoring stations connected to the Florida Power and Light Company transmission lines. The simulated data were obtained by modeling the relevant parts of the utility's transmission system using a University of British Columbia simplified version of the well known Electromagnetic ...
1984-01-01
Review of the study and application on nuclear forensic analysis
International Nuclear Information System (INIS)
For the interests of national security, many scientists who work in the field of nuclear forensic analysis have carried out extensive work in the past on the detection of radioactive material and attributions study, developed a series of scientific and technical means to trace and detect illicit circulation of nuclear materials used to weapons and other radioactive materials which impair public security. All these questions relate to physical, chemical, biological attribution of materials. The nuclear forensic analysis has already become a special, up-to-date sphere of learning. The goal of the study of nuclear forensics is to prevent terrorists from acquiring not only nuclear weapons but also mate- rials that can be used to make such weapons, including radioactive materials for nuclear power plants, and medical radioisotope to and provide us as many clues of environmental links as possible that could help us ...
2009-12-01
Versatile charged particle activation technique for the analysis of the noble metals
Energy Technology Data Exchange (ETDEWEB)
The general usefulness of neutron activation analysis (NAA) for samples containing the platinum group elements (PGE) and Au, either as major or trace constituents, is discussed. Charged particle activation is shown to be a viable or complementary alternative. Proton (6-10 MeV) and alpha particle (9-15 MeV) beams, produced in a tandem Van de Graaff accelerator, have been established to be the most effective choice. By taking advantage of the Coulomb barrier effect and the fact that many charged particle induced reactions have relatively large threshold values, the same instrumental technique can be applied, with minor modifications, to a wide range of materials.
1982-01-01
Versatile charged particle activation technique for the analysis of the noble metals
Energy Technology Data Exchange (ETDEWEB)
The general usefulness of neutron activation analysis (NAA) for samples containing the platinum group elements and Au, either as major or trace constituents, is discussed. Charged particle activation is shown to be a viable or complementary alternative. Proton (6-10 MeV) and alpha particle (9-15 MeV) beams, produced in a Tandem van de Graaff accelerator, have been established to be the most effective choice. By taking advantage of the Coulomb barrier effect and the fact that many charged particle induced reactions have relatively large threshold values, the same instrumental technique can be applied, with minor modifications, to a wide range of materials.
1983-01-01
Monitoring of "1"1"0"mAg in the Daya Bay marine environment
International Nuclear Information System (INIS)
The author describes the Gamma -spectrum analysis results of "1"1"0"mAg, the method used, and the coincidence correction theory on which the analysis is based. The samples were placed at the upper end of the detector. The monitoring results of "1"1"0"mAg in the surrounding marine area from the beginning of operation of the Daya Bay nuclear power plant are reviewed as well. The results showed that "1"1"0"mAg traces were detected in some marine species. However, the concentrations observed are far below the National Standard limits
1999-09-20
Formal Analysis of UMTS Privacy
The ubiquitous presence of mobile communication devices and the continuous development of mo- bile data applications, which results in high level of mobile devices' activity and exchanged data, often transparent to the user, makes privacy preservation an important feature of mobile telephony systems. We present a formal analysis of the UMTS Authentication and Key Agreement protocol, using the applied pi-calculus and the ProVerif tool. We formally verify the model with respect to privacy properties. We show a linkability attack which makes it possible, for individuals with low-cost equipment, to trace UMTS subscribers. The attack exploits information leaked by poorly designed error messages.
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
This study of the inorganic chemical composition of 10 different Nigerian medicinal plant species, using the technique of instrumental neutron activation analysis (INAA), resulted in the determination of the concentrations of 18 major, minor, and trace elements: Al, Ba, Br, Ca, Cl, Eu, Fe, Ga, K, La, Mn, Na, Sb, Sc, Si, Sm, V, and Zn. The parts of the plants used were roots, leaves, and bark. The NBS SRM 1571 Orchard Leaves was also analyzed to assess the accuracy of the procedures used. 21 refs., 4 tables.
1984-04-02
High-throughput proteomics of breast carcinoma cells: a focus on FTICR-MS
Energy Technology Data Exchange (ETDEWEB)
Discovery of better biomarkers for diagnosis, prognosis, and therapy-response prediction is the most critical task of a scientific quest aimed at developing newly designed, tailor-made therapies for patients with cancer. Consequently, a proteome wide analysis, in addition to genomic studies, is an absolute requirement for a complete functional understanding of tumor biology. Ultra-sensitive, high-performance Fourier transform ion cyclotron resonance (FTICR) mass spectrometry (MS) currently holds an important role in fulfilling the demands of biomarker discovery. In this review, we describe the applicability of FTICR MS for breast cancer proteomics, particularly for the analysis of complex protein mixtures obtained from a limited number of cells typically available from clinical specimens.
2008-06-05
British Library Electronic Table of Contents (United Kingdom)
A qualitative method, involving supported liquid?liquid extraction (SLE) and ultra high pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS?MS), was developed for the rapid tentative identification of various drugs of abuse in urine. In this study, 28 drugs and metabolites were covered by the screening procedure. Before analysis, urine samples were extracted by SLE and good extraction recoveries were obtained for most investigated compounds. The UHPLC strategy was then selected for the rapid separation of amphetamines, cocaine, opiates and related compounds in urine. Using columns packed with sub-2??m particles, analysis time was reduced down to 2?min, while maintaining acceptable performance. Finally, the detection was by tandem MS operating in the single reaction...
2009-01-01
Biological and morphological characterization of human neonatal fibroblast cell culture B-HNF-1
British Library Electronic Table of Contents (United Kingdom)
In the present study, human neonatal fibroblasts were isolated from a two-month-old human male. The purpose of the present investigation was the analysis of the morphology (light and transmission electron microscopy), karyotype and growth characteristics of the human neonatal fibroblast cell culture B-HNF-1. Moreover, STR typing and mitochondrial DNA amplification and sequencing was also performed. Analysis of chromosomes count showed that B-HNF-1 cell culture is diploid and has normal male karyotype 46, XY, which was stable during cultivation. The transmission electron microscopy demonstrated the ultra-structure of the B-HNF-1 cells; they have typical morphological features of proteosynthesis-active cells. Large number of fibroblasts bearing different shapes and surface characteristics ad...
2010-01-01
Fostering the commercialization of ultra capacitors
Energy Technology Data Exchange (ETDEWEB)
This document presents the activity of KiloFarad International (KFI), a trade association for the promotion of the interests of the international ultra-capacitor industry through education and representation. KFI provides a forum for the ultra-capacitor industry to work on non-competitive activities (standards, working groups, test procedures etc..). The rest of the document presents some informations about ultra-capacitors technology and some advanced applications in the automotive and telecommunication industries. (J.S.)
2004-07-01
International Nuclear Information System (INIS)
The concentrations of Cd, Co, Cr, Fe, Mo, Ni, Se, Ti, V and Zn in biological fluids, human blood serum and market milk were determined by neutron activation analysis, with enrichment by coprecipitation. The pre-concentration of these trace elements was accomplished by converting the dissolved trace metal ions into their pyrrolidinedithiocarbamate (1-pyrrolidinecarbodithioate) chelates, followed by coprecipitation with a metal carrier such as Ni, Pb or Bi. The coprecipitation was carried out prior to irradiation for the short-lived nuclides (V, Ti and Se) and after irradiation for the other elements. The validity of the method was checked using certified biological reference materials; the concentrations of trace elements found by the proposed method agreed well with the published certified data. The limits of detection for Cd, Co, Cr, Fe, Mo, Ni, Se (obtained through the long-lived isotope "7"5Se) and ...
Energy Technology Data Exchange (ETDEWEB)
New and elaborate techniques for alpha-particle autoradiography of thick specimens based on the plastic nuclear track detector CR-39 have been developed. These permit a full analysis of both trace element and microdistribution of alpha-active nuclides present. The important features of the techniques are: 1) reliable low level configuration down to 10/sup -15/ Ci g/sup -1/, 2) high resolution alpha-particle spectroscopy in CR-39, 3) determination of the absolute abundance of alpha active nuclides present in the specimen, 4) determination of the distribution of emission with height up to 30 microns above the surface of the autoradiograph, 5) the local determination of the radon diffusion coefficient in the specimen which is needed to calculate the activity levels of /sup 222/Rn and daughter nuclei, 6) the analysis of small and large clusters of alpha-particle activity recorded on the autoradiograph. These techniques are ...
1984-06-15
Energy Technology Data Exchange (ETDEWEB)
The thesis explains the development of a mass spectrometerical isotope dilution analysis (MS/DA) for determining trace amounts of Tc. The Tc-97 isotope has been prepared by in-core irradiation of Ru of natural isotopic composition, and used as the indicator isotope. For separation of Tc-97 from the Ru matrix, a method has been developed to quantitatively separate Tc-97 from a high Ru surplus. For determining the isotope ratio for the MS/DA, a mass spectrometrical measuring technique has been found which allows reproducible measurement of the Tc-99/Tc-97 isotope ratio. Positive and, for the first time, also negative thermoionisation has been used as a method of selective ionisation of Tc. The applicability of the MS/DA for Tc trace analysis has been verified using two Al foils doped with Tc-99 or Mo-98, respectively. These have been irradiated in a nuclear reactor, the irradiation of Tc-99 yielding ...
1984-01-01
Spin-resolved magnetic studies of focused ion beam etched nano-sized magnetic structures
International Nuclear Information System (INIS)
Scanning ion microscopy with polarization analysis (SIMPA) is used to study the spin-resolved surface magnetic structure of nano-sized magnetic systems. SIMPA is utilized for in situ topographic and spin-resolved magnetic domain imaging as well as for focused ion beam (FIB) etching of desired structures in magnetic or non-magnetic systems. Ultra-thin Co films are deposited on surfaces of Si(1 0 0) substrates, and ultra-thin, tri-layered, bct Fe(1 0 0)/Mn/bct Fe(1 0 0) wedged magnetic structures are deposited on fcc Pd(1 0 0) substrates. SIMPA experiments clearly show that ion-induced electrons emitted from magnetic surfaces exhibit non-zero electron spin polarization (ESP), whereas electrons emitted from non-magnetic surfaces such as Si and Pd exhibit zero ESP, which can be used to calibrate sputtering rates in situ. We report on new, spin-resolved magnetic microstructures, such as magnetic 'C' states and magnetic vortices, ...
2005-04-01
Migration of strontium in the food chain of plants, animals and man - problems and risks
International Nuclear Information System (INIS)
The aims of investigation were to follow the Sr transport in the food chain from the flora to the fauna and humans, and its dependence on the geological origin og the plant site, industrial emissions, the age and site of plants, the part of plant used for nutrition and the strontium content in the drinking water, to determine the Sr intake of humans with the help of the duplicate method, and to estimate the apparent absorption rate and balance of strontium depending on of the form of diet (mixed or ovolactovegetarian), sex, season, age, region (geological origin of the living space) and method of intake measurement (duplicate or basket method). Strontium, an ultra trace element widespread in the earth's crust, is not essential and only mildly toxic for plants, animals and man according to current knowledge. The biological essentiality of Sr has not been investigated yet. Amoeba species living in sea water use Sr for the formation of their ...
2008-10-15
Trace metals in tap water from Tehran, Iran
Energy Technology Data Exchange (ETDEWEB)
A total of 272 tap water samples were collected from 68 homes throughout the city of Tehran. Analysis for cadmium, zinc, lead, copper, arsenic, iron and manganese showed some accumulation of these metals in household piping overnight. However, the concentration of all metals was in the parts per billion (ug/l) range and well below international standards. Heavy metals in Tehran's drinking water therefore, do not pose a significant acute health hazard. 19 references, 2 tables.
1986-01-01
The nucleotide sequence and organization of nuclear 5S rRNA genes in yellow lupine
International Nuclear Information System (INIS)
We have isolated a genomic clone containing 'Lupinus luteus' 5S ribosomal RNA genes by screening with 5S rDNA probe clones that were hybridized previously with the initiator methionine tRNA preparation (contaminated) with traces of rRNA or its degradation products). The clone isolated contains ten repeat units of 342 bp with 119 bp fragment showing 100% homology to the 5S rRNA from yellow lupine. Sequence analysis indicates only point heterogeneities among the flanking regions of the genes. (author). 6 refs, 3 figs.
1993-01-01
The Formation of Multipoles during the High-Temperature Creep of Austenitic Stainless Steels
DEFF Research Database (Denmark)
It is shown that multipole dislocation configurations can arise during power-law creep of certain austenitic stainless steels. These multipoles have been analysed in some detail for two particular steels (Alloy 800 and a modified AISI 316L) and it is suggested that they arise either during instantaneous loading or during the primary creep stage. Trace analysis has shown that the multipoles are confined to {1 1 1} planes during primary creep but are not necessarily confined to these planes during steady-state creep unless they are pinned by interstitials.
1981-01-01
Radiochemistry at the Philips Research Laboratories, Eindhoven, The Netherlands
International Nuclear Information System (INIS)
The activities of the radiochemical section (part of the Analytical Chemistry Group) deal mostly with problems of composition. Activation analysis with thermal neutrons serves for most of the trace element analyses either with or without chemical separations. Ge(Li) spectrometry has been increasingly automated so that many analyses can now be performed by relatively unskilled personnel. In a number of analyses an A.V.F.-cyclotron was employed: such an accelerator can deliver not only different types of charged particles at variable energies but also fast neutrons. (T.G.).
1977-01-01
Post-inversion stage of regional metamorphism of coals
Energy Technology Data Exchange (ETDEWEB)
A study is made of the metamorphism of coals in Kuznetsk Basin. To interpret the stages of coalification, measurements were used of the indicators of vitrinite along the hinges of folds, graphic plottings of isometamorphism of coals, analysis of interrelationships of the isolines of coal metamorphism with isopachites covering their deposits. The elevation of the coal mass of Kuzbass in the post-inversion time was accompanied by the formation of steep linear folds and longitudinal bending of their hinges. As a consequence of this, the hinges of the folds in beds of the same name occurred at different depths from the modern surface, however coal metamorphism along the hinges has not changed. In the Kuznetsk Basin there are no traces of post-inversion coalification.
1982-01-01
Landslides affecting sedimentary characteristics of reservoir basin
British Library Electronic Table of Contents (United Kingdom)
Typhoons Aere (2004) and Matsa (2005) caused high nephelometric turbidity in the Shihmen reservoir in northern Taiwan, jeopardizing the operation of the reservoir for several days, and ultimately impacting the living conditions and economy of the downstream residents. The torrential rains caused landslides and debris flows in upland areas, and flowed into riverbeds, likely contributing significantly to the suspended sediment yields in the reservoir. This investigation elucidates how upland landslides affect sediment attributes in the reservoir basin. Study methods including field observations, spatial analysis in GIS and aerial photo interpretation are adopted to trace the sediment sources and contributing factors to the landslide. Torrential rains induced landslides and debris-flows uplan...
2010-01-01
Investigation of Two-Phase Flow Regime Maps for Development of Thermal-Hydraulic Analysis Codes
Energy Technology Data Exchange (ETDEWEB)
This reports is a literature survey on models and correlations for determining flow pattern that are used to simulate thermal-hydraulics in nuclear reactors. Determination of flow patterns are a basis for obtaining physical values of wall/interfacial friction, wall/interfacial heat transfer, and droplet entrainment/de-entrainment. Not only existing system codes, such as RELAP5-3D, TRAC-M, MARS, TRACE, CATHARE) but also up-to-date researches were reviewed to find models and correlations
2010-04-15
Long cylindrical mirror sections with an 'Alliptical' cross- section and an interfoci distance of approximately 1 m can be produced by means of diamond fly cutting. However, because of the finite tool radius, the generated profile is basically not an ellipse, but an equidistant ellipse or 'Allipse'. By numerical ray tracing analysis two unique conjugated 'A-points' can be found that are optically nearly equivalent with pure elliptical focal points. A reversed modeling procedure is used to predict the optimum machine configuration for producing just the required ellipse sections. Optical figure quality, focal line position and straightness are tested by a simple deflectometer set-up.
1999-09-01
Energy Technology Data Exchange (ETDEWEB)
Elemental analysis of some medicinal plants used in the Indian Ayurvedic system was performed by employing instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted by gamma ray spectrometry using an efficiency calibrated high resolution high purity germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the elements under study. The variation in elemental concentration in same medicinal plants samples collected in summer, winter and rainy seasons was studied and the biological effects of these elements on human beings are discussed. (orig.)
2009-07-01
Analysis by mass spectroscope device provided with ion source of induced plasma
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.
Non-destructive Imaging of Individual Bio-Molecules
Radiation damage is considered to be the major problem that still prevents imaging an individual biological molecule for structural analysis. So far, all known mapping techniques using sufficient short wave-length radiation, be it X-rays or high energy electrons, circumvent this problem by averaging over many molecules. Averaging, however, leaves conformational details uncovered. Even the anticipated use of ultra-short but extremely bright X-ray bursts of a Free Electron Laser shall afford averaging over 10^6 molecules to arrive at atomic resolution. Here we present direct experimental evidence for non-destructive imaging of individual DNA molecules. In fact, we show that DNA withstands coherent low energy electron radiation with deBroglie wavelength in the Angstrom regime despite a vast dose of 10^8 electrons/nm^2 accumulated over more than one hour.
2009-01-01
Verification of a nuclear analysis system for fast reactors using BFS-62 critical experiment
International Nuclear Information System (INIS)
Critical experiments have been analyzed to verify a nuclear analysis system for fast reactors used in Japan Nuclear Cycle Development Institute (JNC). The experiments were performed in a collaboration work between JNC and the Institute of Physics and Power Engineering of Russia to dispose Russian surplus weapons plutonium, focusing on the effect of the introduction of uranium-plutonium mixed-dioxide (MOX) fuel and stainless steel reflector into the current BN-600 core that is comprised of UO_2 fuel and blanket. The analysis results agreed well with measured values on most of the nuclear characteristics. The accuracies are comparable to those obtained for the conventional MOX fueled fast reactors. It suggests that the JNC analysis system can analyze accurately nuclear characteristics in uranium fueled cores as well. A significant improvement was achieved on the sodium void reactivity by employing an ...
2004-12-01
International Nuclear Information System (INIS)
A gel-type "9"9Mo-"9"9"mTc generator using Titanium-Molybdate target (TiMo-target) as column packing was developed in Radioisotope Department, the Dalat Nuclear Research Institute [1]. The concentration of trace elements in TiMo-target and radionuclidic purity in "9"9"mTc solution eluted from this type of generator were studied for quality control purpose. The monostandard method in neutron activation analysis has been applied to determine the concentration of trace impurities in titanium-molybdate target. For neutron activation analysis, TiMo samples were irradiated in the different channels of nuclear reactor IVV-9 at a neutron flux of maximum 2.1 x 10"1"3 n.cm"-"2s"-"1. The following chemical element impurities were determined: Na, W, Co, Fe, Zn, Ag, Sb and Cr. The gamma ray emitted nuclides found in "9"9"mTc solution eluted from our "9"9"mTc generator were the following: "6"5Zn, "6"0Co, "1"1"0"mAg, ...
2004-06-01
Energy Technology Data Exchange (ETDEWEB)
The theoretical analysis of a partially-ionized hydrogen gas flow (gas temperatures of approximately 10,000 to 20,000 K) through a particular class of magnetohydrodynamic (MHD) generators and the preliminary design of these MHD generators as open cycle, electric power supplies are performed. Analysis of the gas flow through these ultra-high temperature MHD generators requires a coupled gas dynamics/radiative heat transfer solution. Gas dynamics are modeled by a set of quasi-one-dimensional, nonlinear differential equations which account for friction, convective and radiative heat transfer and the interaction between the ionized gas and applied magnetic field. Radiative heat transfer is modeled using non-gray, absorbing-emitting two- and three-dimensional P-1 approximations which permit an arbitrary variation of the spectral absorption coefficient with frequency. Gas dynamics and radiative heat transfer are coupled through ...
1990-01-01
Energy Technology Data Exchange (ETDEWEB)
Some crops of important nutritive requirements have been collected from farmlands located in Bitsichi an old tin mining town in north central region of Nigeria. The food crops were analyzed in order to determine trace element concentrations level using Neutron Activation Analysis (NAA). The activity concentrations due to natural radionuclides in the food samples and soil samples collected within the root zone of the crops were also determined using gamma-ray spectrometry (GRS). The NAA results obtained showed higher concentration of Potassium among the essential elements in all the crops. Calcium concentration in both maize and Guinea corn was below detection limit and also Zn in Green beans, sweet potato and cassava. The trace elements; Sc, Hf, Sm, and Th, were below detection limit in all the crops except in Green beans. Rubidium (Rb) and lanthanum (La) were below detection limits only in Cabbage. The activity ...
2007-01-15
Estimation of trace elements in some anti-diabetic medicinal plants using PIXE technique
Energy Technology Data Exchange (ETDEWEB)
Trace elemental analysis was carried out in various parts of some anti-diabetic medicinal plants using PIXE technique. A 3 MeV proton beam was used to excite the samples. The elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb and Sr were identified and their concentrations were estimated. The results of the present study provide justification for the usage of these medicinal plants in the treatment of diabetes mellitus (DM) since they are found to contain appreciable amounts of the elements K, Ca, Cr, Mn, Cu, and Zn, which are responsible for potentiating insulin action. Our results show that the analyzed medicinal plants can be considered as potential sources for providing a reasonable amount of the required elements other than diet to the patients of DM. Moreover, these results can be used to set new standards for prescribing the dosage of the herbal drugs prepared from these plant materials.
2006-08-15
British Library Electronic Table of Contents (United Kingdom)
This paper explores the potential of combining substance-flow modelling with water and wastewater sampling to trace consumption-related substances emitted through the urban wastewater. The method is exemplified on sucralose. Sucralose is a chemical sweetener that is 600 times sweeter than sucrose and has been on the European market since 2004. As a food additive, sucralose has recently increased in usage in a number of foods, such as soft drinks, dairy products, candy and several dietary products. In a field campaign, sucralose concentrations were measured in the inflow and outflow of the local wastewater treatment plant in Linkoping, Sweden, as well as upstream and downstream of the receiving stream and in Lake Roxen. This allows the loads emitted from the city to be estimated. A method c...
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
Abstract: The recent National Academy of Sciences report on forensic sciences states that the study of fire patterns and debris in arson fires is in need of additional work and eventual standardization. We discuss a recently introduced method that can provide predicted evaporation patterns for ignitable liquids as a function of temperature. The method is a complex fluid analysis protocol, the advanced distillation curve approach, featuring a composition explicit data channel for each distillate fraction (for qualitative, quantitative, and trace analysis), low uncertainty temperature measurements that are thermodynamic state points that can be modeled with an equation of state, consistency with a century of historical data, and an assessment of the energy content of each distillate fraction...
2011-01-01
Nuclear analytical techniques in Cuban sugar industry
Energy Technology Data Exchange (ETDEWEB)
This paper is a review concerning the application of Nuclear Analytical Techniques in the Cuban sugar industry. The most complete elemental composition of final molasses (34 elements) and natural zeolites (38) this last one employed as an auxiliary agent in sugar technological processe4s has been performed by means of instrumental Neutron Activation Analysis (INAA) and X-Ray Fluorescence Analysis (XRFA). The trace elemental sugar cane soill-plant relationship and elemental composition of different types of Cuban sugar (raw, blanco-directo and refine) were also studied. As a result, valuable information referred to the possibilities of using these products in animal and human foodstuff so as in the other applications are given. (author). 34 refs., 6 figs., 1 tab.
1997-12-01
Micro-analysis of ?salt weathering? on cement paste
British Library Electronic Table of Contents (United Kingdom)
Normally, concrete technologists attribute salt weathering, salt crystallization or physical attack to the deterioration of concrete that is partially exposed to sulfate environment. However, there are few convincing evidences supporting this view. The purpose of this paper is to check by means of extensive micro-analysis if traces of sulfate crystals are present in the paste. This would enable to verify in a direct way whether salt weathering really causes cement paste damage or not.In this research, cement paste and cement?fly ash paste specimens were partially exposed to sodium sulfate and magnesium sulfates solution under a constant storage condition (20 ? 2 ?C, and 60 ? 5% RH) and a sharply fluctuating environment (40 ? 2 ?C and 35 ? 5% RH for 24 h, then 10 ? 1 ?C and 85 ? 5% RH, also...
2011-01-01
International Lens Design Conference, Monterey, CA, June 11-14, 1990, Proceedings
Energy Technology Data Exchange (ETDEWEB)
The present conference on lens design encompasses physical and geometrical optics, diffractive optics, the optimization of optical design, software packages, ray tracing, the use of artificial intelligence, the achromatization of materials, zoom optics, microoptics and GRIN lenses, and IR lens design. Specific issues addressed include diffraction-performance calculations in lens design, the optimization of the optical transfer function, a rank-down method for automatic lens design, applications of quadric surfaces, the correction of aberrations by using HOEs in UV and visible imaging systems, and an all-refractive telescope for intersatellite communications. Also addressed are automation techniques for optics manufacturing, all-reflective phased-array imaging telescopes, the thermal aberration analysis of a Nd:YAG laser, the analysis of illumination systems, athermalized FLIR optics, and the design of array systems using ...
1990-01-01
Energy Technology Data Exchange (ETDEWEB)
Leafy samples often used as medicine in the Indian Ayurvedic system and vegetables were analyzed for 20 elements (As, Ba, Br, Ca, Ce, Cr, Cs, Co, Eu, Fe, K, La, Na, Rb, Sb, Sc, Sm, Sr, Th, Zn) by employing Instrumental Neutron Activation Analysis (INAA). The samples were irradiated at the 100 kW TRIGA-MAINZ nuclear reactor and the induced activities were counted by gamma ray spectrometry using an efficiency calibrated high resolution High Purity Germanium (HPGe) detector. The concentration of the elements in the medicinal and vegetable leaves and their biological effects on human beings are discussed.
1999-05-01
Energy Technology Data Exchange (ETDEWEB)
Specific parts of several plants (fruits, leaves, stem, bark and roots) often used as medicines in the Indian Ayurvedic system have been analysed for 20 elements (As, Ba, Br, Ca, Cl, Co, Cr, Cu, Fe, K, Mn, Mo, Na, P, Rb, Sb, Sc, Se, Sr and Zn) by employing instrumental neutron activation analysis (INAA). The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted using high resolution gamma ray spectrometry. Most of the medicinal herbs have been found to be rich in one or more of the elements under study. (Author).
1997-01-01
British Library Electronic Table of Contents (United Kingdom)
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. This new method is a significant improvement over current approaches, with features including a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), trace chemical analysis of each distillate fraction, and a corrosivity assessment of each distillate fraction. In the present contribution, we present the application of the advanced distillation curve method to a bio-derived crude oil prepared from swine manure. One motivation behind the work was to precisely measure the distillation curve of the oil derived from swine manure with our advanced distillation apparatus and compare the bio-derived oil to traditional pe...
2008-01-01
MICRONUTRIENTS/TRACE ELEMENTS - Global Change Master Directory (GCMD)
Total concentrations of major and trace elements were determined in samples of the epilithic lichen Umbilicaria decussata from 24 ice-free areas in coastal ...
Study of silicon damage caused by ultra-low energy boron implantation
International Nuclear Information System (INIS)
Ultra-shallow junction formation in deep submicron Si devices is limited by anomalous diffusion of the dopant, which is related to the release of interstitials from defect clusters formed during the implantation of energetic ions or the subsequent annealing. The work described in this dissertation is concerned with the effects of low energy B ion implantation, especially damage formation, clustering and its annealing. After a review of the stopping and ranges of energetic ions in Si, the formation of implant damage, in particular of point defects, their migration, agglomeration and annihilation, including the involvement of dopant ions, is considered. A description of the Salford ultra low energy implanter is given and the main analysis technique, medium ion energy scattering (MEIS) reviewed. Additional analytical techniques used, such as secondary ion mass spectrometry (SIMS), 4-point probe and cross section transmission ...
Iridium and PGE in sedimentary rocks; Iridium et platinoides dans les roches sedimentaires
Energy Technology Data Exchange (ETDEWEB)
The detection limit of Instrumental Neutron Activation Analysis (INAA), about a few microgram per kg, is not sufficient to determine iridium concentrations in most geological samples. Use of the coincidence counting of the 316 and 468 keV gamma-rays emitted during the decay of {sup 192}Ir, improved the sensitivity (0.01 microgram per kg). The high iridium content of the clay layers from the Cretaceous-Tertiary transition (KTB) has been considered as an evidence of the extra-terrestrial origin of the KTB mass extinction. However some results indicate that a significant part of the iridium content in sediments has a volcanic origin. Radiochemical Neutron Activation Analysis (RNAA) in some KTB samples and in basic and ultra-basic rocks show that, unlike in volcanic products, no PGE (platinoids) fractionation appears in KTB samples. The nearby chondritic PGE pattern supports an extra-terrestrial origin for the KTB iridium ...
1994-12-31
Energy Technology Data Exchange (ETDEWEB)
For rational use of energy resources, the process technology which allows harmonization and multiplication of conflicting characteristics was developed for development of new ceramic system materials. This paper summarizes the result in fiscal 1997. On a structural reaction process among creation technologies of ultra-reliable structure, study was made on structure control and hot-working technology through atmosphere control in ceramics synthesis. On basic technology for analysis and evaluation, study was made on the effect of particle bridging on strengthening and toughening of ceramic materials. Study was also made on a toughness expression mechanism, FEM model analysis of particle bridging, and crack growth resistance of ceramics. On control of solid solution precipitation, new alumina ceramics with high strength, hardness and wear resistance was obtained by transgranularly precipitating nano-size particles from a ...
1998-03-01
Assessment of trace element contents of chicken products from turkey
Energy Technology Data Exchange (ETDEWEB)
Due to the consumption of chicken and chicken products in Turkey at high ratio, trace metal content of chicken and chicken products from Turkey were determined by atomic absorption spectrometry after microwave digestion. The accuracy of the method was confirmed by analysis of standard reference material (NIST SRM 1577b Bovine liver). Trace element content in various parts of chicken samples and chicken products were to be in the range of 0.10-114 {mu}g/g for copper, 0.25-6.09 {mu}g/kg for cadmium, 0.01-0.40 {mu}g/g for lead, 0.10-0.91 {mu}g/g for selenium, 0.05-3.91 {mu}g/g for manganese, 0.06-0.10 {mu}g/g for arsenic, 0.01-0.72 {mu}g/g for chromium, 0.01-2.08 {mu}g/g for nickel, 0.01-0.02 {mu}g/g for cobalt, 0.10-1.90 {mu}g/g for aluminium, 1.21-24.3 {mu}g/g for zinc, 2.91-155 {mu}g/g for iron. The levels of lead in some analyzed chicken products were higher than the recommended legal limits for human consumption.
2009-04-30
International Nuclear Information System (INIS)
Some crops of important nutritive requirements have been collected from farmlands located in Bitsichi an old tin mining town in north central region of Nigeria. The food crops were analyzed in order to determine trace element concentrations level using Neutron Activation Analysis (NAA). The activity concentrations due to natural radionuclides in the food samples and soil samples collected within the root zone of the crops were also determined using gamma-ray spectrometry (GRS). The NAA results obtained showed higher concentration of Potassium among the essential elements in all the crops. Calcium concentration in both maize and Guinea corn was below detection limit and also Zn in Green beans, sweet potato and cassava. The trace elements; Sc, Hf, Sm, and Th, were below detection limit in all the crops except in Green beans. Rubidium (Rb) and lanthanum (La) were below detection limits only in Cabbage. The activity ...
Technology and Policy for Sustainable Development
The development of short-sea shipping will be fostered by the deployment of tracking and tracing systems,
International Nuclear Information System (INIS)
Selenium (Se), zinc (Zn), magnesium (Mg), molybdenum (Mo) and vanadium (V) in 28 types of Egyptian common foodstuffs as well as drinking and irrigation water samples were determined using neutron activation analysis (NAA) and atomic absorption spectrometry (AAS). The samples were collected from 74 sites over 13 governorates as well as the Nile river, wells and tap water in the regions of the Nile Delta, Sinai, the east and west desert, and north and south Egypt. These trace elements were chosen according to international references, which show the close relationship of their deficiencies to immunity-related diseases. Calculation values of daily uptake per capita were made with the results of analysis. The results, as calculated per 100 g dry weight, showed that some Egyptian foods are rich in Se including such fish (0.94 #mu#g), sesame (0.88 #mu#g), beef meat (0.48 #mu#g), instant tea (0.42 #mu#g), mushroom (0.34 #mu#g) and ...
Trace analysis in cadmium telluride by heavy ion induced X-ray emission and by SIMS
International Nuclear Information System (INIS)
The possibilities of using both selective heavy ion induced X-ray emission and secondary ion mass spectroscopy (SIMS), for the identification of impurities present at low concentrations in cadmium telluride are examined. The relative concentrations of the impurities along CdTe crystals have been determined by exciting the X-ray emission of the elements in several slices with Ar and Kr ions and by comparing the relative characteristic X-ray emission yields. As a consequence of the quasimolecular inner shell ionization mechanism in heavy ion-atom collisions, Ar and Kr ions allow a strong excitation of the main impurities seen by SIMS namely Si, Cl and Ge, As, with only a minor contribution of Cd and Te. From the changes of the concentrations of the various impurities along the crystal, informations about segregation coefficients and compensation can be obtained.
2007-02-01
Thermoelectrically cooled water trap
Energy Technology Data Exchange (ETDEWEB)
A water trap system based on a thermoelectric cooling device is employed to remove a major fraction of the water from air samples, prior to analysis of these samples for chemical composition, by a variety of analytical techniques where water vapor interferes with the measurement process. These analytical techniques include infrared spectroscopy, mass spectrometry, ion mobility spectrometry and gas chromatography. The thermoelectric system for trapping water present in air samples can substantially improve detection sensitivity in these analytical techniques when it is necessary to measure trace analytes with concentrations in the ppm (parts per million) or ppb (parts per billion) partial pressure range. The thermoelectric trap design is compact and amenable to use in a portable gas monitoring instrumentation.
2006-02-21
Scale prevention with special reference to threshold treatment
Energy Technology Data Exchange (ETDEWEB)
Various chemical, physical, and mechanical methods to prevent unwanted deposition of mineral scale are described. The suitability of the different methods, which largely depends on the specific features and requirements of the system involved, is discussed. Special emphasis is placed upon the threshold treatment, where the growth process is retarded by the addition of trace amounts of growth inhibitors. Growth experiments have been performed on barium sulfate and calcium sulfate dihydrate seed crystals, suspended in a supersaturated solution with and without organic bisphosphonates as inhibitors. Two methods are selected for the analysis of the growth data. A degree of inhibition is defined to obtain a quantitative description of the influence of a growth inhibitor on the growth rate of the crystals. In addition the influence of the molecular structure of various bisphosphonates with different substituents is shown. The effect of a ...
1983-01-01
Quasi-stationary and transient patterns in jets
Apparent evolution of relativistic flows as traced by radio emission results from a combination of several factors related to propagation of relativistic blobs or shocks, velocity, density and pressure stratification of the underlying flow, plasma instability and (possibly also) phase and time travel effect. This combination can create an intricate and chaotic patterns of the observed morphological changes in radio emission, which complicates the analysis and interpretation of kinematic and physical properties of the jet plasma. Recent studies have indicated that slow and quasi-stationary patterns in jets are most likely formed by plasma instabilities while faster, superluminally moving patterns are related to highly relativistic plasma condensations produced by the nuclear flares. Some of the stationary patterns may also be related to recollimation shocks or locations where strong non-thermal continuum is produced in jets. Similarities and ...
2011-01-01
Augmenting Actual Life Through MUVEs
The necessity of supporting more and more social interaction (and not only the mere information sharing) in online environments is the disruptive force upon which phenomena ascribed to the Web2.0 paradigm continuously bud. People interacting in online socio-technical environments mould technology on their needs, seamlessly integrating it into their everyday life. MUVEs (Multi User Virtual Environments) are no exception and, in several cases, represent the new frontier in this field. In this work we analyze if and how MUVEs can be considered a mean for augmenting communities (and more in general people) life. We trace a framework of analysis based on four main observations, and through these lenses we look at Second Life and at several projects we are currently developing in that synthetic world.
2008-01-01
Minerals and trace elements determination in diets by neutron activation analysis
International Nuclear Information System (INIS)
In the present study 12 diets, each one consisting of a pool of seven day diets, composed by four meals: breakfast, lunch, dinner and snack, adequate in energy and macro nutrients according to the RDA (Recommended Daily Allowance) recommendations, were elaborated and offered to a group of 12 men (19-42 years). The diets were collected by duplicate portion technique and dried by two different processes: freeze drying and 60 deg C ventilated oven drying. In the total, 24 diets were analyzed. The content of some minerals and trace elements (Ca, Fe, Mg, Mn, Na, Se and Zn) were determined by Instrumental Neutron Activation Analysis. The validation of methodology was made by analysis of the reference materials Typical Diet (NIST SRM 1548"a), Orchard Leaves (NIST SRM 1541) and Peach Leaves (NIST SRM 1547). The results observed by two different drying processes used were statistically compared by test T of Student. It was possible ...
2002-08-11
Microprocessor-controlled anodic stripping voltammeter for trace metal analysis in tap water
Energy Technology Data Exchange (ETDEWEB)
The construction and use of a portable, microprocessor controlled anodic stripping voltameter for on-site simultaneous metal analysis of copper, lead and cadmium in tap water is discussed. The instrumental system is comprised of a programmable controller which permits keying in analytical parameters such as sparge time and plating time: a rotating cell for efficient oxygen removal and amalgam formation; and, data handling via a minicomputer or analog pen recorder. Plating and stripping potentials are controlled by a digital potentiostat; stripping is done using a staircase waveform with measurement of the current after a one msec delay. In this way charging current effects are minimized. Results of tap water analysis showed 3 +- 1 ..mu..g/L lead, 22 +- 0.3 ..mu..g/L copper, and less than 0.2 ..mu..g/L cadmium for a Berkeley, California tap water, and 1-1000 ..mu..g/L Cu, 1 -2 ..mu..g/L Pb for ten samples of Seattle, Washington tap water. ...
1984-06-01
Carbon Dioxide Information Analysis Center: FY 1992 activities
Energy Technology Data Exchange (ETDEWEB)
During the course of a fiscal year, Oak Ridge National Laboratory`s Carbon Dioxide Information Analysis Center (CDIAC) distributes thousands of specialty publications-numeric data packages (NDPs), computer model packages (CMPs), technical reports, public communication publications, newsletters, article reprints, and reference books-in response to requests for information related to global environmental issues, primarily those pertaining to climate change. CDIACs staff also provides technical responses to specific inquiries related to carbon dioxide (CO{sub 2}), other trace gases, and climate. Hundreds of referrals to other researchers, policy analysts, information specialists, or organizations are also facilitated by CDIAC`s staff. This report provides an account of the activities accomplished by CDIAC during the period October 1, 1991 to September 30, 1992. An organizational overview of CDIAC and its staff is supplemented by a detailed ...
1993-03-01
Energy Technology Data Exchange (ETDEWEB)
The United States and Russia have agreed to jointly develop a solar dynamic (SD) system for flight demonstration on the Russian Mir space station starting in late 1997. Two important components of this SD system are the solar concentrator and heat receiver provided by Russia and the US, respectively. This paper describes optical analysis of the concentrator and solar flux predictions on target receiver surfaces. The optical analysis is performed using the code CIRCE2. These analyses account for finite sun size with limb darkening, concentrator surface slope and position errors, concentrator petal thermal deformation, gaps between petals, and the shading effect of the receiver support struts. The receiver spatial flux distributions are then combined with concentrator shadowing predictions. Geometric shadowing patterns are traced from the concentrator to the target receiver surfaces. These patterns vary with time depending on ...
1995-12-31
X-ray and UV-light irradiation effects on oxide superconducting thin films
International Nuclear Information System (INIS)
Oxide superconducting thin films were irradiated with X-rays and ultra-violet (UV) light, and induced radiation effects on electrical and chemical properties were examined by transport measurement, X-ray diffraction analysis (XRD), diamagnetization measurement and X-ray photoemission spectroscopy (XPS). After irradiation for ErBa_2Cu_3O_x films with X-rays emitted from a Rh tube for 100 hours, superconductivity was remarkably damaged, destroying the zero-resistance state. The UV-light irradiation for Bi_2Sr_2CaCu_2O_x films was performed in He gas of about 500 Pa with a low pressure mercury lamp. The superconductivity was gradually degraded with the UV irradiation time up to 70 minutes. In both cases, adequate oxygen-annealing treatments restored superconductivity. The X-ray photoemission spectra showed that the mean Cu valence of the films was decreased approximately from +2 to +1 by the irradiation. From these results we can find that ...
WIDGET: System Performance and GRB Prompt Optical Observations
The WIDeField telescope for Gamma-ray burst Early Timing (WIDGET) is used for a fully automated, ultra-wide-field survey aimed at detecting the prompt optical emission associated with Gamma-ray Bursts (GRBs). WIDGET surveys the HETE-2 and Swift/BAT pointing directions covering a total field of view of 62 degree x 62 degree every 10 secounds using an unfiltered system. This monitoring survey allows exploration of the optical emission before the gamma-ray trigger. The unfiltered magnitude is well converted to the SDSS r' system at a 0.1 mag level. Since 2004, WIDGET has made a total of ten simultaneous and one pre-trigger GRB observations. The efficiency of synchronized observation with HETE-2 is four times better than that of Swift. There has been no bright optical emission similar to that from GRB 080319B. The statistical analysis implies that GRB080319B is a rare event. This paper summarizes the design and operation of the WIDGET system and ...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
A 2-stage cold (non-tritium) PMR system was tested with the ITER mix in61 days of continuous operation. No decrease in performance was observed over the duration of the test. Decontamination factor (DF) was found to increase with decreasing inlet rate. Decontamination factors in excess of 1.4 {times} 10{sup 5} were obtained, but the exact value of the highest DF could not be determined because of analysis limitations. Results of the 61-day test were used to design a 2-stage PMR system for use in tritium testing. The PMR system was scaled up by a factor of 6 and built into a glovebox in the Tritium Systems Test Assembly (TSTA) of the Los Alamos National Laboratory. This system is approximately 1/5th of the expected full ITER scale. The ITER mix was injected into the PMR system for 31 hours, during which 4.5 g of tritium were processed. The 1st stage had DF = 200 and the 2nd stage had DF = 2.9 {times} 10{sup 6}. The overall DF = 5.8 {times} 10{sup 8}, which is ...
1996-12-31
International Nuclear Information System (INIS)
A 2-stage cold (non-tritium) PMR system was tested with the ITER mix in 61 days of continuous operation. No decrease in performance was observed over the duration of the test. Decontamination factor (DF) was found to increase with decreasing inlet rate. Decontamination factors in excess of 1.4x10"5 were obtained, but the exact value of the highest DF could not be determined because of analysis limitations. Results of the 61-day test were used to design a 2-stage PMR system for use in tritium testing. The PMR system was scaled up by a factor of 6 and built into a glovebox in the Tritium Systems Test Assembly (TSTA) of the Los Alamos National Laboratory. This system is approximately 1/5"t"h of the expected full ITER scale. The ITER mix was injected into the PMR system for 31 hours, during which 4.5 g of tritium were processed. The 1"s"t stage had DF =200 and the 2"n"d stage had DF=2.9x10"6. The overall DF=5.8x10"8, which is greater than ITER requirements. 3 refs., 10 ...
1996-06-16
Energy Technology Data Exchange (ETDEWEB)
In this study, the effects of 325nm wavelength ultraviolet light irradiation on pitting corrosion behavior of type 340 stainless steel in a neutral chloride solution are studied. Further, the change of passive film with the light irradiation is analyzed using x-ray photoelectron spectroscopy. The mains results obtained therefrom are stated below. Pitting potential can be shifted in noble direction by the ultraviolet light irradiation. The effect of ultraviolet light irradiation is ore prominent in the pitting corrosion process than that in the passive film formation. The result of the analysis in terms of the birth and death stochastic probability process shows that pitting corrosion rate is decreased remarkably by the ultraviolet light irradiation at the formation of passive film, while the repassivation is slightly expedited by the ultraviolet light irradiation. On the other hand, the repassivation rate is increased a little by the ultraviolet light irradiation ...
1998-06-20
Energy Technology Data Exchange (ETDEWEB)
Research and development has been performed on photochromic materials expected to be used in ultra-high density recording, high resolution indication and photoswitches. With regard to molecular orientation in the ternary system mixed LB film, the result of structural analysis by XPM spectrum revealed that the acceptor constituent in the LB film is so structured that it is separated and laminated with two other constituents, and that the sensitizer constituent and the donor constituent are not recognized of being separated definitely. Regarding the electron movement reaction in the solid phase system, a photo-current measuring experiment was carried out on the laminated film which is vacuum-deposited with the ternary system comprising of the donor, sensitizer, and acceptor. It was concluded that the observed photo-current reflects the electron movement reaction in the solid phase as it is. For the photo-current in the LB film, increase in the ...
1990-03-01
Full scale testing of wind turbine blade to failure - flapwise loading
Energy Technology Data Exchange (ETDEWEB)
A 25m wind turbine blade was tested to failure when subjected to a flapwise load. With the test setup, it was possible to test the blade to failure at three diffe-rent locations. The objective of these tests is to learn about how a wind turbine blade fails when exposed to a large flapwise load and how failures propagate. The report shows also results from ultra sonic scan of the surface of the blade and it is seen to be very useful for the detection of defects, especially in the layer between the skin laminate and the load carrying main spar. Acoustic emission was successfully used as sensor for the detection of damages in the blade during the test. The report contains measurements of the total deflection of the blade, the local deflection of the skin and the load carrying main spar and also measurement of strain all as a function of the applied load and up to failure of the blade. The 'post mortem' analysis and description of ...
2004-06-01
Trace element analysis in CRM of plant origin by inductively coupled plasma mass spectrometry
International Nuclear Information System (INIS)
Three CRMs of plant origin (SRM 1515 Apple Leaves, SRM 1570a Trace Elements in Spinach Leaves, and SRM 1575 Pine Needles) were used for analytical quality assurance of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, and Pb determination by ICP-MS. The samples were decomposed using microwave assisted pressurized digestion by HNO_3 and HNO_3 + H_2O_2 mixture and temperature programmed dry ashing. Concentrations of elements in samples were evaluated by external calibration. All samples, blanks, and standards were spiked to 100 #mu#g/L concentration of In and Bi as internal standards. During the measurement, signals of "5"2Cr, "5"3Cr, "5"4Fe, "5"5Mn, "5"9Co, "6"0Ni, "6"2Ni, "6"3Cu, "6"5Cu, "6"6Zn, "9"5Mo, "1"1"1Cd, "1"1"2Cd, "1"1"5In, "2"0"6Pb, "2"0"7Pb, "2"0"8Pb and "2"0"9Bi were monitored. Results of Pb, Cd, Cu, Zn, Mo and Co determination were in good agreement with certified values. In order to obtain accurate results for As at low levels, it was necessary to ...
1997-04-21
Energy Technology Data Exchange (ETDEWEB)
The K site near Seoul began landfilling in 1992. The landfilled wastes include municipal solid waste (66.4%), construction residues (20.4%), water and wastewater sludges (trace levels), and hazardous waste (trace levels). The water content of the municipal solid waste is very high (47.3%); as a result, the leachate level (average E.L.) of the landfill, the design value of which is 7.0 m, was measured at 10.3 m in January 1995 and is increasing. The increase of leachate level in the landfill site causes a problem with slope stability. The leachate level at each disposal stage divided by the intermediate cover layer was calculated with the HELP (Hydrologic Evaluation of Landfill Performance) model and calibrated with the data measured from February 1993 to June 1995. Also, the hydraulic conductivities of the waste layer and the intermediate cover layer in each stage were calibrated continuously with HELP model analysis. To ...
1996-12-31
International Nuclear Information System (INIS)
Full text.Sediments are the ultimate sink of trace elements. The total metal analysis may only give information concerning possible enrichment of metals. The analysis of metal partitioning in the different chemical components of sediments (exchangeable, carbonate, easily reducible, moderately reducible, organic and residual); give a detailed information on the way in which these metals are bound to sediments, their mobilization capacity and their ability to affect water quality under different environmental conditions. The studied river basin is dominated by limestone formation, the enrichment of metals in the carbonate sediment fraction is a high probability. The objective of the study was to determine the percentage of the total metal content (Fe, Mn, Zn, Cu and Pb) in the six chemical fractions of the bed load sediments of Nahr-Ibrahim river during the dry season and verify the role of carbonate for metal sediment ...
1999-11-02
The mask detection technology for occluded face analysis in the surveillance system.
The surveillance systems have been widely used in automatic teller machines (ATMs), banks, convenient stores, etc. For example, when a customer uses the ATM, the surveillance systems will record his/her face information. The information will help us understand and trace who withdrew money. However, when criminals use the ATM to withdraw illegal money, they usually block their faces with something (in Taiwan, criminals usually use safety helmets or masks to block their faces). That will degrade the purpose of the surveillance system. In previous work, we already proposed a technology for safety helmet detection. In this paper, we propose a mask detection technology based upon automatic face recognition methods. We use the Gabor filters to generate facial features and utilize geometric analysis algorithms for mask detection. The technology can give an early warning to save-guards when any "customer" or "intruder" blocks his/her face information ...
2005-05-01
Integrated microelectrode arrays for trace-metal analysis of aqueous solutions
Energy Technology Data Exchange (ETDEWEB)
Stripping Voltammetry (SV) at microelectrodes has gained increased interest in the analysis of aqueous solutions due to its ability to analyze low concentrations (ppb) of electroactive metallic species in solution. Existing integrated circuit (IC) technology allows the inexpensive fabrication of microelectrodes with dimensions on the order of microns and with a high degree of uniformity and reproducibility. Additional circuitry, both multiplexing and signal conditioning, can be placed directly onto the sensor offering increased sensitivity and flexibility. Multi-element electrochemical sensors containing arrays of Pt, Au, and Ag electrodes and capable of individual measurement through built-in multiplexing or simultaneous measurement at the appropriate potential ranges for each individual electrode were fabricated using existing 2 micron IC technology. Results of simultaneous measurements of low concentrations of Cd, Pb, Cu, As, and Hg in solution indicate that ...
1995-12-31
Complete factorization scheme analysis of $F_2^{\\gamma}(x,Q^2)$ in the next--to--leading order QCD is performed. It is shown that the presence of the inhomogenous term in the evolution equations for parton distribution functions of the photon implies qualitative change in the way factorization mechanism works in photon--hadron and photon--photon collisions as compared to hadron--hadron ones. The incompletness of the existing NLO analyses of $F_2^{\\gamma}(x,Q^2)$ is pointed out and its origins traced back to the misinterpretation of the behaviour of $q^{\\gamma}(x,M)$ as a function of in the LO photonic coefficient function $C_{\\gamma}^{(0)}(x)$ is given and smooth transition between the properties of virtual and real photon discussed. A simple way of avoiding the problems with the term $\\ln(1-x)$ appearing in the standard expression for $C_{\\gamma}^{(0)}(x)$ in the case of the reaal photon is proposed.
1998-01-01
International Nuclear Information System (INIS)
Along with the shrinkage of LSI geometries, a higher quality of ultrapure water has been continuously required. Analytical technology for ultrapure water has also progressed before ultrapure water production technology improvements. In this study, we performed optimization of the analytical conditions for the direct analysis of acid droplets, and established an analytical technology for measurements of trace amounts of metallic impurities deposited on a wafer surface by means of Vapor Phase Decomposition (VPD)/Inductively Coupled Plasma Mass Spectrometry (ICP-MS). As a result, analytical technology for metallic elements of the 1x10"8 atoms/cm"2 level on wafer surface has been established. By applying analytical technology to the wafer that has been contacted with ultrapure water, a new evaluation technology for ultrapure water quality by means of wafer surface contamination has been established. We confirmed good correlations between metal ...
2010-07-01
An off-axis Cassegrain optimal design for short focal length parabolic solar concentrators
Energy Technology Data Exchange (ETDEWEB)
The present work addresses an off-axis Cassegrain optical concentration system. The specific primary collector analyzed, a short focal length parabolic concentrator, is at the University of Florida`s Energy Park. A secondary hyperbolic reflective element was designed to redirect the solar radiation from the primary focal plane to an off-axis target on the polar axis of the primary concentrator. This ground level target will be required for planned experimental work. The analysis was performed using a numerical ray tracing procedure that incorporates both random and systematic errors due to slope and surface irregularities. The optimization process varied secondary element size, curvature, and offset angle, and yielded information required for optimum design. As a single secondary element was found impractical, three elements were designed for use at various time of the year. The numerical analysis predicts that typically 70 ...
1995-02-01
Energy Technology Data Exchange (ETDEWEB)
This project was supported through ERDA to demonstrate that the temporal distribution of tritium can be documented by the analysis of bound hydrogen in annual tree-ring samples. The project focuses on two sample locations at the Savannah River Site (SRS), a nuclear material production facility located in Aiken, SC. The SRS provided samples of cross-sections from a single tree that were to be pooled together for analysis. Annual tree-rings were identified in each cross-section sample and separated for the period 1954 to 1993. These annual samples were ground and chemically treated to separate the hollocellulose fraction of the wood, then subsequently combusted and the resulting water counting using low-level liquid scintillation counting equipment. Additionally, the ground annual tree-rings were gamma-counted to determine any temporal variation in radionuclide activity and analyzed with x-ray fluorescence to find any temporal variation in ...
1995-03-21
The Atmospheric Trace ... - NASA Langley Science Directorate
Trace gas molecules absorb specific wavelengths of incoming solar ... These data(with information collected from similar experiments carried on balloons, rockets, ... The ATMOS sensor instrumentis a state-of-the-art version of a 19th century ...
UK PubMed Central (United Kingdom)
Rhizosphere acidification by Fe-deficient bean (Phaseolus vulgaris L.) plants was induced by trace amounts of divalent metal ions (Zn, Mn). The induction of this Fe-efficiency reaction...Full Text Available
1989-05-01
Phytoremediation of Soil Trace Elements
This chapter summarizes research progress in development of phytoremediation technologies. Some soils have become contaminated by trace elements enough to kill plants, inhibit soil organisms, and/or threaten wildlife, humans or the environment. Traditional remediation by dig and haul methods are v...
A trace gas technique for measuring clothing microclimate air exchange rates
UK PubMed Central (United Kingdom)
Crockford, G. W., Crowder, M., and Prestidge, S. P. (1972).Brit. J. industr. Med.,29, 378-386. A trace gas technique for measuring clothing microclimate...Full Text Available
1972-10-01
Screening of Flexible Cables by Nonlinear Resistance ...
... Abstract : Two traces in flexible cables used in the Milstar agile beam antenna system failed during acceptance testing. ...
1994-01-10
RAYMAN: A FORTRAN Computer Code for Tracing Rays ...
... Descriptors : *COMPUTERIZED SIMULATION, *HUMAN BODY, *WOUND BALLISTICS, COMPUTER PROGRAMS, PROJECTILES, MATRICES ...
1977-11-01
Energy resolution estimation of hemispherical deflector analyzers using electron ray-tracing code
International Nuclear Information System (INIS)
... Authority (Turkey) The Scientific and Technical Research Council of Turkey
2006-08-22
Determination of major metals and their trace states in ground water in Lebanon
International Nuclear Information System (INIS)
1999 p. 148 Lebanon Saad, Zeinab Commission Libanaise d'Energie Atomique,
1999-11-02
The separation and determination of trace elements in iron ore
International Nuclear Information System (INIS)
The separation, concentration, and determination of trace elements in iron ores are described. After the sample has been dissolved, the iron is separated by liquid-liquid extraction with a liquid cation-exchanger, di-(2-ethylhexyl) phosphoric acid. The trace elements aluminium, cadmium, calcium, chromium, cobalt, copper, lead, magnesium, manganese, mercury, potassium, sodium, vanadium, and zinc are determined in the aqueous phase by atomic-absorption spectrophotometry.
2008-05-01
A phenomenological interpretation of trace impurity transport
Energy Technology Data Exchange (ETDEWEB)
An interpretive theory of trace impurity transport in tokamaks is presented. It is based on an earlier phenomenological approach developed by the authors for describing tokamak plasma transport experiments. The present model is used to explain disparate phenomena observed in ALCATOR C and DITE in a unified phenomenological framework. Predictive numerical calculations are presented for DITE conditions. If experimentally confirmed, the model could be used to correlate plasma properties with trace impurity behaviour. (orig.)
1989-10-01
Traces of evidence. Nuclear forensics and illicit trafficking
International Nuclear Information System (INIS)
An IAEA databank lists a number of reported cases of illicitly trafficked nuclear or other radioactive materials. Apart from the traditional concern with nuclear proliferation, the post September 11th public is now wary of a possible attack by terrorists with a nuclear or radiation dispersion device (RDD). Until now, the seized quantities have not been sufficient to manufacture a nuclear explosive device, but they might be enough to construct an RDD. Recognizing the latent global challenge to public health and safety, the G8 States (Japan, USA, Germany, France, UK, Italy, Canada, and Russia) have called for 'joint international efforts to identify and suppress illicit supply' of, and demand for, nuclear material and to deter potential traffickers. One measure gaining in significance is to identify seized material and trace it back to its origin the objective of an emerging science known as nuclear forensics. Repeatedly nuclear or other radioactive material of ...
2003-06-01
PV Conversion Technologies, Session: OPV, Sensitized, Seed (Presentation)
Energy Technology Data Exchange (ETDEWEB)
The NREL Sensitized Solar Cell (SSC) Core Program supports the Solar America Initiative by: (1) targeting new devices and processes for commercialization by 2015 that are less expensive, more efficient, highly reliable, and environmentally benign; (2) collaborating with DOE OS/BES to conduct basic research targeting breakthroughs in key areas, such as ultra-high efficiency and/or ultra-low cost materials and devices.
2008-04-01
Reflection tomography using finite element method ray tracing
Energy Technology Data Exchange (ETDEWEB)
The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. After subdividing subsurface into triangular element we shoot off the ray into subsurface by the Snell`s law. And then after taking the ray path which is similar to proper ...
1996-12-01
International Nuclear Information System (INIS)
Exploration for epithermal Au has been active lately in the Aegean Sea of the eastern Mediterranean Basin, both in the islands of the Quaternary arc and in those of the back-arc region. The purpose of this study was the structural mapping and analysis for a preliminary investigation of possible epithermal gold mineralization, using remotely sensed data and techniques, structural and field data, and geochemical information, for a specific area on the Island of Lesvos. Therefore, Landsat-TM and SPOT-Pan satellite images and the Digital Elevation Model (DEM) of the study area were processed digitally using spatial filtering techniques for the enhancement and recognition of the geologically significant lineaments, as well as algebraic operations with band ratios and Principal Component Analysis (PCA), for the identification of alteration zones. Statistical rose diagrams and a SCHMIDT projection Stereo Net were generated from the lineament maps and ...
2000-12-01
Energy Technology Data Exchange (ETDEWEB)
Known trace-matrix-separation and enrichment procedures for the refractory metals Mo and W use very time-consuming batch-techniques. This paper presents the application of a quasicontinuous liquid chromatographic (LC) technique as a step towards automated ultratrace separation. The anionic peroxo complexes from Mo(VI) and W(VI) are used for the trace-matrix-separation. Optimization of the peroxide concentration permits a complete removal of all cationic analyte traces on the HPLC-suitable cation exchanger Nucleosil SA. The high chromato-graphic efficiency also allows a direct ion chromatographic separation of the removed traces. This leads to conclusions about the contribution of the analyte traces on the trace-matrix-separation column and the limits of determination. (author). 13 refs.; 12 figs.; 5 tabs.
1991-11-20
Investigation by XRF and XRD of Zn and Fe in Fe{sub x} Zn{sub 1-x} thin films
Energy Technology Data Exchange (ETDEWEB)
Fe{sub x}Zn{sub 1-x} alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K{beta}/K{alpha} x-ray intensity ratios of Zn and Fe in Fe{sub x}Zn{sub 1-x} thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi {sup 241}Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in Fe{sub x}Zn{sub 1-x} thin films for different values of x. ...
2008-12-15
Investigation by XRF and XRD of Zn and Fe in Fex Zn1-x thin films
International Nuclear Information System (INIS)
FexZn1-x alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K?/K? x-ray intensity ratios of Zn and Fe in FexZn1-x thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi 241Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in FexZn1-x thin films for different values of x. The reason for this change may be that the ...
2008-12-01
SE and I content in military total diet
International Nuclear Information System (INIS)
Selenium and iodine are trace elements that play an important role in health of man and animals. Concerning supply of both elements it is important to meet nutritional needs. According to discoveries selenium is a part of an active group of glutathione peroxidase enzyme. It prevents necrotic changes in liver, muscle dystrophy and has impact on growth. Extensive studies on content of selenium in plant and animal origin products were started in the beginning of the seventies in Western Europe (Frankenberger, et al., 1998). The aim of our work was to determine selenium and iodine content in total diets of Slovene military. Slovene military nutrition is based on its own nutritional standards, which determine 200 #mu#g of iodine and 50 #mu#g of selenium in daily diet (Rep. Slovenija Ministrstvo za Obrambo, 1994). To determine if the amounts of both elements meet the standards we have analysed 20 total daily diets from four different barracks within a two month period. ...
2003-06-10
Performance of the upgraded LTP-II at the ALS Optical Metrology Laboratory
Energy Technology Data Exchange (ETDEWEB)
The next generation of synchrotrons and free electron laser facilities requires x-ray optical systems with extremely high performance, generally of diffraction limited quality. Fabrication and use of such optics requires adequate, highly accurate metrology and dedicated instrumentation. Previously, we suggested ways to improve the performance of the Long Trace Profiler (LTP), a slope measuring instrument widely used to characterize x-ray optics at long spatial wavelengths. The main way is use of a CCD detector and corresponding technique for calibration of photo-response non-uniformity [J. L. Kirschman, et al., Proceedings of SPIE 6704, 67040J (2007)]. The present work focuses on the performance and characteristics of the upgraded LTP-II at the ALS Optical Metrology Laboratory. This includes a review of the overall aspects of the design, control system, the movement and measurement regimes for the stage, and analysis of the performance by a ...
2008-07-14
PIXE-PIGE analysis of some Indian medicinal plants
Energy Technology Data Exchange (ETDEWEB)
The quantitative estimation of various trace element concentrations in medicinal plants is necessary for determining their effectiveness in treating various diseases and for understanding their pharmacological action. Elemental concentrations of some selected medicinal plants of north east India was measured by proton induced X-ray emission (PIXE) and proton induced {gamma}-ray emission (PIGE) techniques. PIXE measurements were carried out using 2.4 MeV collimated protons from the 3 MV tandetron accelerator of NCCCM, Hyderabad (India) while the PIGE measurements were carried out using 3 MeV protons from the same accelerator in the same laboratory. Accuracy and precision of the techniques were assured by analyzing certified reference materials in the same experimental conditions. Various elements of biological importance in man's metabolism were found to be present in varying concentrations in the studied medicinal plants and no toxic heavy metals were ...
2010-06-15
Energy Technology Data Exchange (ETDEWEB)
Recently there has been much concern with the ability of plants to uptake heavy metals from their surroundings. With the development of instrumental techniques with low detection limits such as inductively coupled plasma-mass spectrometry (ICP-MS), attention is shifting toward achieving faster and more elegant ways of oxidizing the organic material inherent in environmental samples. Closed-vessel microwave dissolution was compared with conventional methods for the determination of concentrations of cerium, samarium, europium, terbium, uranium and thorium in a series of samples from the National Institute of Standards and Technology and from fields in Idaho. The ICP-MS technique exhibited detection limits in parts-per-trillion and linear calibration plots over three orders of magnitude for the elements under study. The results obtained by using nitric acid and hydrogen peroxide in a microwave digestion system for the analysis of reference materials showed close ...
1997-08-01
Integral Field Unit Observations of NGC 4302: Kinematics of the Diffuse Ionized Gas Halo
We present moderate resolution spectroscopy of extraplanar diffuse ionized gas (EDIG) emission in the edge-on spiral galaxy NGC 4302. The spectra were obtained with the SparsePak integral field unit (IFU) at the WIYN Observatory. The spectra are used to construct position-velocity (PV) diagrams at several ranges of heights above the midplane. Azimuthal velocities are directly extracted from the PV diagrams using the envelope tracing method, and indicate an extremely steep dropoff in rotational velocity with increasing height, with magnitude ~30 km/s/kpc. We find evidence for a radial variation in the velocity gradient on the receding side. We have also performed artificial observations of galaxy models in an attempt to match the PV diagrams. The results of a statistical analysis also favor a gradient of ~30 km/s/kpc. We compare these results with an entirely ballistic model of disk-halo flow, and find a strong dichotomy between the observed ...
2007-01-01
International Nuclear Information System (INIS)
A simple sample decomposition and laser fluorimetric determination of uranium at trace level is reported in certain refractory minerals, like ilmenite, rutile, zircon and monazite; environmental samples viz. soil and sediments; industrial waste materials, such as, coal fly ash and red mud. Ilmenite sample is decomposed by heating with ammonium fluoride. Rutile, zircon and monazite minerals are decomposed by fusion using a mixture of potassium bifluoride and sodium fluoride. Environmental and industrial waste materials are brought into solution by treating with a mixture of hydrofluoric and nitric acids. The laser induced fluorimetric determination of uranium is carried out directly in rutile, zircon and in monazite minerals and after separation in other samples. The determination limit was 1 #mu#g x g"-"1 for ilmenite, soil, sediment, coal fly ash and red mud samples, and it is 5 #mu#g x g"-"1 for rutile, zircon and monazite. The method is also developed for the ...
2005-10-01
CSI: A Paradigm for Behavior-oriented Delivery Services in Mobile Human Networks
We propose behavior-oriented services as a new paradigm of communication in mobile human networks. Our study is motivated by the tight user-network coupling in future mobile societies. In such a paradigm, messages are sent to inferred behavioral profiles, instead of explicit IDs. Our paper provides a systematic framework in providing such services. First, user behavioral profiles are constructed based on traces collected from two large wireless networks, and their spatio-temporal stability is analyzed. The implicit relationship discovered between mobile users could be utilized to provide a service for message delivery and discovery in various network environments. As an example application, we provide a detailed design of such a service in challenged opportunistic network architecture, named CSI. We provide a fully distributed solution using behavioral profile space gradients and small world structures. Our analysis shows that user behavioral ...
2008-01-01
Analysis of Spatio-Temporal Preferences and Encounter Statistics for DTN Performance
Spatio-temporal preferences and encounter statistics provide realistic measures to understand mobile user's behavioral preferences and transfer opportunities in Delay Tolerant Networks (DTNs). The time dependent behavior and periodic reappearances at specific locations can approximate future online presence while encounter statistics can aid to forward the routing decisions. It is theoretically shown that such characteristics heavily affect the performance of routing protocols. Therefore, mobility models demonstrating such characteristics are also expected to show identical routing performance. However, we argue models despite capturing these properties deviate from their expected routing performance. We use realistic traces to validate this observation on two mobility models. Our empirical results for epidemic routing show those models' largely differ (delay 67% & reachability 79%) from the observed values. This in-turn call for two important activities: (i) ...
2010-01-01
A rapid, radiometric assay for sucrose synthase
Energy Technology Data Exchange (ETDEWEB)
Investigations of sucrose synthase in maize root tips have required development of a means to circumvent the rapid decline of activity observed after extraction dialysis and either synthetic or degradative assays. Several protease inhibitors were tested; although PMSF increased initial activity, no inhibitor prevented the drop in activity with time. Western blot analysis indicated that activity decline was not associated with protein degradation. Therefore, a procedure was developed which (1) shortened extraction-to-assay period from ca. 24 hours to 7 minutes, (2) simplified previous assays and (3) reduced the amount of tissue required. Extract was desalted with spun columns and the {sup 14}C-UDPG product recovered with DEAE ion exchange paper. The minute quantities of product recovered can be concealed by the presence of trace impurities in the {sup 14}C-sucrose utilized. DEAE ion exchange paper was used to remove interfering radio-labelled ...
1990-05-01
Radon gas monitoring survey for the determination of Radon Prone Areas in Lombardia
Energy Technology Data Exchange (ETDEWEB)
Region Lombardia has carried out a radon gas monitoring survey on its territory to localize radon prone areas as by law 241/00 enacted. To plan the survey, the Lombardia territory has been divided into two different types according to the morphology as well as the presence of a substratum of rock. The area with hills and mountains has been investigated with more attention compared to the plain because we can assume higher variability in radon concentration distribution due to the geological and morphological characteristics. The territory subdivision was based on the standard grid.. of the techniregional cartography (8 x 5 km). To perform radon indoor concentration measurements about 3600 measuring points were selected. They are located at the ground floor of buildings with the characteristics to ensure the tests are representative and comparable. It has also been taken into account evaluations done with previous surveys in accordance with the defined specification of the sites. The ...
2006-07-01
Energy Technology Data Exchange (ETDEWEB)
Population residing in the northern part of the Chelyabinsk oblast and the south eastern part of the Sverdlovsk oblast of Russia affected to accidental exposure since 1957. The territory (East Ural Radioactive Trace - EURT) was contaminated after explosion of container with highly radioactive wastes at the Mayak Production Association. Studies of health effects of exposure in the southern, head part of EURT are conducted in the Ural Research and Practical Center of Radiation Medicine (U.R.P.R.M.). In the 1990's U.R.P.C.R.M. formed a cohort of EURT within Chelyabinsk oblast (14,500 cases and 19,400 external controls). The cohort was followed in 1957-1987 and the results of the study are discussed by Crestinina et al. First results of study on exposure late health effects among rural population in the northern part of the EURT are presented in this paper. Firstly, or the period 1958-2000 a statistically significant increase in cancer mortality associated ...
2006-07-01
Non-catalytic and catalytic wet air oxidation of pharmaceuticals in ultra-pure and natural waters
British Library Electronic Table of Contents (United Kingdom)
A wet air oxidation (WAO) process was applied to four selected pharmaceuticals (metoprolol, naproxen, amoxicillin, and phenacetin) individually dissolved in ultra-pure water, varying the temperature and oxygen pressure. Due to the moderate (amoxicillin) or low (metoprolol, naproxen, and phenacetin) efficiency found in the oxidation of these pollutants, a catalytic wet air oxidation (CWAO) process was then tested using a platinum catalyst supported on multi-walled carbon nanotubes (CNT). In this CWAO process, the pharmaceuticals were dissolved together in ultra-pure water and in four natural water matrices-a reservoir water, a groundwater, and two waters from different municipal wastewater treatment plants. On the basis of the measurements of their removals, a discussion is given of the inf...
2011-01-01
Machinability of magnesium alloy in ultra-precision diamond cutting
Energy Technology Data Exchange (ETDEWEB)
This paper deals with an experimental study of ultra-precision diamond cutting of magnesium alloy (AZ31). In order to investigate the machinability such as the cutting force and the surface integrity and understand the problems in a micro cutting, the experiments on the diamond cutting of magnesium alloy and pure aluminum with an ultra-precision turning machine has been carried out. The machinability of magnesium alloy was compared with that of pure aluminum and discussed. Consequently, both the thrust force component and the surface roughness obtained by cutting of magnesium alloy became larger than that of pure aluminum. It was also found that the inclusions or the defects in the work material caused to generate the scratches on the finished surface and influenced the integrity of mirror surface. (orig.)
2003-07-01
Free-electron laser driven by the LBNL laser-plasma accelerator
Energy Technology Data Exchange (ETDEWEB)
A design of a compact free-electron laser (FEL), generating ultra-fast, high-peak flux, XUV pulses is presented. The FEL is driven by ahigh-current, 0.5 GeV electron beam from the Lawrence Berkeley National Laboratory (LBNL) laser-plasma accelerator, whose active acceleration length is only a few centimeters. The proposed ultra-fast source (~;;10 fs) would be intrinsically temporally synchronized to the drive laser pulse, enabling pump-probe studies in ultra-fast science. Owing to the high current (>10 kA) of the laser-plasma-accelerated electron beams, saturated output fluxes are potentially greater than 10^13 photons/pulse. Devices based both on self-amplified spontaneous emission and high-harmonic generated input seeds, to reduce undulator length and fluctuations, are considered.
2008-08-04
International Nuclear Information System (INIS)
An Ultra-Low-Carbon 19% Cr-11% Ni Stainless Steels used in nuclear fuel reprocessing plants where highly corrosion resistance in nitric acid is required has been developed. This steel has optimized the chemistry composition to decrease inclusions and deformation-induced martensitic transformation. The formation of deformation-induced martensite has the potential danger of accelerating corrosion in nitric acid. In this paper, effects of cold reduction and martensitic transformation on corrosion resistance of Ultra-Low-Carbon Stainless Steels in nitric acid are discussed. The developed steel showed excellent corrosion resistance during long-term exposure to nitric acid. (author).
A numerical study of ultra-short-pulse reflectometry
Energy Technology Data Exchange (ETDEWEB)
Ultra-short-pulse reflectometry is studied by means of the numerical integration of a one-dimensional full-wave equation for ordinary modes propagating in a plasma. The numerical calculations illustrate the potential of using the reflection of ultra-short-pulse, microwaves as an effective probe of the density profile even in the presence of significant density fluctuations. The difference in time delays of differing frequency components of the microwaves can be used to deduce the density profile. The modification of the reflected pulses in the presence of density fluctuations is examined and can be understood based on considerations of Bragg resonance. A simple and effective profile-reconstruction algorithm using the zero-crossings of the reflected pulse and subsequent Abel inversion is demonstrated. The robustness of the profile reconstruction algorithm in the presence of a sufficiently small amplitude density perturbation is assessed.
1994-05-01
Reflection tomography using finite element method ray tracing
Energy Technology Data Exchange (ETDEWEB)
The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. Since the FEM (Finite Element Method) ray tracing we have developed goes well the inverse velocities structure, we can apply the inversion problem to complex ...
1996-12-01
Numerical simulation of trace tests in atmosphere in Daya Bay nuclear power site
International Nuclear Information System (INIS)
The validation of the forecast model for early emergency response to nuclear accidents is evaluated by trace tests in atmosphere in Daya Bay nuclear power site. The simulation experiment of the Daya Bay nuclear power site shows that the particle spreading image and the time-integrated concentration distribution given by plume concentration prediction model can perform the variation of pathway of the pollutant transport, as well as the effects of topography on transport and diffusion of pollutants. The simulation of five trace tests in field shows that 59.1% of ratios between predicted results and observed results are within the range of 10, and 41% of ratios are within the range of 5 approximately. (authors)
2005-09-01
Laser ray-tracing method for optical testing.
We have developed a novel laser ray-tracing method to measure aberrations in optical systems. It consists of delivering narrow laser pencils (by a laser scanner), recording the spots that are formed on the image plane (with a CCD camera), and computing the position of each centroid. This approach could be considered an experimental (approximate) implementation of standard numerical ray tracing. Several tests and experiments, including a direct comparison with a Hartmann-Shack wave-front sensor, provided highly satisfactory results that confirmed the validity of the method and revealed potential advantages. PMID:18073906
1999-07-15
Energy Technology Data Exchange (ETDEWEB)
A Guide to Seismic Un{sup *} (SU)(2)-Examples of Data Processing(part 1), Data Input and the Preparation of Trace Headers - This is part 1, the preparatory section for the preliminary series for the SU, the two cases of reflectional seismic survey and processing employing the SU, which explains how to input input data from the SEG-Y format tapes and to set trace header. (NEDO)
1999-10-01
Ultra high field magnetic resonance imaging
International Nuclear Information System (INIS)
Understanding human brain function, brain development and brain dysfunction is one of the great challenges of the twenty first century. Biomedical imaging has now run up against a number of technical constraints that are exposing limits to its potential. In order to overcome the current limits to high-field magnetic resonance cerebral imaging (MRI) and unleash its fullest potential, the Cea has built NeuroSpin, an ultra-high-field neuroimaging facility at its Saclay centre (in the Essonne). NeuroSpin already boasts three fully operational MRI systems. The first is a 3-tesla high-field system and the second is a very-high-field 7-tesla system, both of which are dedicated to clinical studies and investigations in humans, while the third is an ultra-high-field 17.65-tesla system designed for studies on small animals. In 2011, NeuroSpin will be commissioning an 11.7-tesla ultra-high-field system of unprecedented power that is ...
System Design and Applications of the Ultra Small ... - GLTRS - NASA
The advanced technologies of Ka-Band systems such as high gain spot .... sometimes used based on link requirements for a specific application. .... received at NASA LeRC from a Ku-band satellite and retransmitted to the USAT at Ka-Band. .... and to the Office of Management and Budget, Paperwork Reduction Project ...
Railgun. Challenge to ultra-high speed; Railgun. Chokosoku eno chosen
Energy Technology Data Exchange (ETDEWEB)
A railgun has an armature driven between two rail-like conductors. In other words, it is a linear drive device system that drives airframes by using the Lorentz`s force. The system is expected as a next-generation high-speed transport means, or as a means to create such ultimate fields as ultra-high pressures, ultra-high temperatures, and ultra-ferromagnetic fields. This paper is a report on investigations on the relevant technological trends as surveyed by the investigation committee at the Institute of Electrical Engineers of Japan using research reports published inside and outside the country. The reported themes cover explanations from the construction to the pulse power supply that forms the core of the technology, problems in switching, recent status of research and development, and to application fields. Compatibility in the high-level electrical and mechanical performances demanded in the railgun is not as easy as ...
1995-09-12
Mesozoic Era of relativistic heavy ion physics and beyond.
In order to understand how matter 15 billion years ago in the form of quarks, gluons and leptons at a temperature of 2 (times) 10(sup 12) (degrees)K evolved to become today's Universe, the goal of relativistic and ultra-relativistic heavy ion physics is t...
1994-01-01
Breaking the 1000-gene barrier for Mimivirus using ultra-deep genome and transcriptome sequencing
UK PubMed Central (United Kingdom)
BackgroundMimivirus, a giant dsDNA virus infecting Acanthamoeba, is the prototype of the mimiviridae family, the latest addition to the family of the nucleocytoplasmic...Full Text Available
International Nuclear Information System (INIS)
Our purpose in this work was to develop an automatic boundary detection method for mammographic masses and to rigorously test this method via statistical analysis. The segmentation method utilized a steepest change analysis technique for determining the mass boundaries based on a composed probability density cost function. Previous investigators have shown that this function can be utilized to determine the border of the mass body. We have further analyzed this method and have discovered that the steepest changes in this function can produce mass delineations that include extended projections. The method was tested on 124 digitized mammograms selected from the University of South Florida's Digital Database for Screening Mammography (DDSM). The segmentation results were validated using overlap, accuracy, sensitivity, and specificity statistics, where the gold standards were manual traces provided by two expert radiologists. ...
2004-10-01
Energy Technology Data Exchange (ETDEWEB)
Exhaust fine and ultra fine particle numbers, particle sizes, mass, shape, structure and density were studied from Euro II - EEV emission level heavy-duty vehicles. For total particle emission factors city buses were run on dynamic conditions simulating city bus driving. The new heavy-duty chassis dynamometer of VTT was used. Vehicles were a comprehensive sample of current city bus fleet, the type approved emission level of which was Euro II - Euro III. Also cleaner engines of Euro IV to EEV targeted emission level were included: CRT, CNG, DPF. Particle emissions of these buses were extremely low; numbers 1/100 - 1/1000 and masses 1/10 - 1/100 of those of the predominating techniques. Morphological properties of fine particle populations that represent majority of particle size distribution (Da < 500 nm) are being analyzed by image processing (Matlab) from electron microscopical images (SEM, ESEM and TEM) as a function of particle size. Particles from ...
2004-07-01
SERAPHIM: A propulsion technology for fast trains
Energy Technology Data Exchange (ETDEWEB)
The Segmented Rail Phased Induction Motor (SERAPHIM) is a compact, pulsed linear induction motor (LIM) offering a unique capability for very high speed train propulsion. It uses technology developed for the Sandia coilgun, an electromagnetic launcher designed to accelerate projectiles to several kilometers per second. Both aluminum cylinders and plates were accelerated to a kilometer per second (Mach 3) by passing through a sequence of coils which were energized at the appropriate time. Although this technology was developed for ultra-high velocity, it can be readily adapted to train propulsion for which, at sea level, the power required to overcome air resistance limits the operational speed to a more modest 300 mph. Here, the geometry is reversed. The coils are on the vehicle and the ``projectiles`` are fixed along the roadbed. SERAPHIM operates not by embedding flux in a conductor, but by excluding it. In this propulsion scheme, pairs of closely spaced coils on ...
1995-06-01
Long-term high temperature fatigue properties of new structural materials for nuclear reactors
Energy Technology Data Exchange (ETDEWEB)
This study aims to evaluate fatigue strength properties at long-term high temperature of 316FR steels developed for structural materials applied to high temperature components in the 21st Century such as Demonstration FBR, and to obtain design indicators on high temperature strength properties arranged on chemical composition and grain size on a base of 316FR stainless steels. As results obtained by the study, it could be found that as a result of systematic examinations on temperatures and strain rate dependence on symmetric triangular strain waveform of 316FR steels between 500 to 600degC, temperature of fatigue life, and strain rate dependence can be integrally evaluated by a parameter analysis method developed by authors and life prediction at ultra low strain rate of less than 10{sup -6}/s and its experimental verification could be carried out. And, it was also found that as a result of evaluation of creep fatigue life and creep rupture ...
2003-01-01
Long-term high temperature fatigue properties of new structural materials for nuclear reactors
International Nuclear Information System (INIS)
This study aims to evaluate fatigue strength properties at long-term high temperature of 316FR steels developed for structural materials applied to high temperature components in the 21st Century such as Demonstration FBR, and to obtain design indicators on high temperature strength properties arranged on chemical composition and grain size on a base of 316FR stainless steels. As results obtained by the study, it could be found that as a result of systematic examinations on temperatures and strain rate dependence on symmetric triangular strain waveform of 316FR steels between 500 to 600degC, temperature of fatigue life, and strain rate dependence can be integrally evaluated by a parameter analysis method developed by authors and life prediction at ultra low strain rate of less than 10"-"6/s and its experimental verification could be carried out. And, it was also found that as a result of evaluation of creep fatigue life and creep rupture ...
2003-01-01
Energy Technology Data Exchange (ETDEWEB)
Fatigue tests were accomplished with a series of specimens doped with trace elements of a hardened Fe-Ni-Cr alloy, cast and hardened with intermetallic phases for determining the influence of these elements on the high temperature strength properties. The results of extensive fatigue tests show that even small contents of Te, Bi, Se, Pb, Tl and Zn considerably influence the life and creep processes especially after longer running periods, when added individually or combinedly. In contrast to this, the fatigue ductility is reduced by trace element additions even with short running periods. The order in which the metallic trace elements influence the fatigue properties nearly correlates with earlier work concerning Ni- and Co-superalloys. (orig.)
1993-01-01
International Nuclear Information System (INIS)
A new in vivo method has been developed for the precise observation of RES activity. Both Escherichia coli endotoxin 100 #mu#g/100 g i.v. (LPS) and radiodetoxified endotoxin 100 #mu#g/100 g body weight i.v. (RD-LPS, TOLERIN) increased the granulopectic activity of RES. The RD-LPS was more effective. The preparation containing trace elements also increased the activity of RES. The treatment consisting of the use of both trace elements and RD-LPS proved to be the most effective. The activity of RES was inversely proportional to various doses of X-ray irradiation (7, 8, 9 Gy). Trace elements and RD-LPS even improved the immunity system of animals having deteriorated RES. (N.T.).
British Library Electronic Table of Contents (United Kingdom)
This paper describes the modeling of horizontal steam generator with the TRACE code and calculation results of a loss-of-feedwater (LOF-10) experiment at the PACTEL facility. Parallel Channel Test Loop (PACTEL) is an integral test facility for a VVER-440 type nuclear reactor. The main objectives were to prepare a simulation model for its horizontal steam generator with the TRACE thermal hydraulic code and assess different modeling options of the code. PACTEL experiment LOF-10 was chosen for this assessment. The calculation results showed that TRACE is capable in simulating horizontal steam generator behavior both in steady state and during loss-of-feedwater transient. The phenomenon of heat transfer from primary to secondary side, steam superheating and flow reversal in the lowest heat exc...
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
Monthly sampling of slightly alkaline arsenic-rich stream in the Mokrsko gold deposit revealed seasonal variations in dissolved Zn, Cu, As and Mo. Concentrations of trace metal cations (Zn, Cu) increased as much as 330 and 178%, respectively, from minimum mean values at autumn to maximum mean values at spring. In contrast, concentrations of trace element oxyanions (As, Mo) revealed opposite seasonal pattern with increase to 189% (As) and 123% (Mo) during summer?autumn, indicating that in-stream biogeochemical process(es) played the main role in controlling the seasonal variations of these trace elements. The trace elements were mainly scavenged by low crystalline Mn oxyhydroxide and Fe oxyhydroxide (ferrihydrite). Results are consistent with sorption and coprecipitation processes controlli...
2011-01-01
Relationship of Optical Coating on Thermal Radiation ...
drical Enclosures Using a Numerical Ray Tracing Technique. NASA. TM-I02527, 1990 . Buckley, H.: Radiation from the Interior of a Reflecting Cylinder. Philos. ...
British Library Electronic Table of Contents (United Kingdom)
Ichnogenera belonging to cleft-foot and wedge-foot bivalves can in most cases be distinguished. This paper addresses the taxonomy of locomotion traces made by wedge-foot bivalves. Ichnogenera Ptychoplasma Fenton and Fenton and Oravaichnium Plicka and Uhrova are reviewed together with related ichnotaxa. Both are interpreted as the locomotion traces of non-cleft, wedge-foot bivalves. Both are usually preserved as hypichnial ridges that include a distinctive bioprint of amygdaloid segments. Ptychoplasma is dominated by amygdaloid segments whereas Oravaichnium is wall-like with only sporadic amygdaloid segments. Ichnospecies of Ptychoplasma are distinguished on the basis of their continuity: P. excelsum Fenton and Fenton (the type) is a relatively continuous trace fossil consisting largely of ...
2011-01-01
Genomic view of the evolution of the complement system
UK PubMed Central (United Kingdom)
The recent accumulation of genomic information of many representative animals has made it possible to trace the evolution of the complement system based on the presence or absence of each complement...Full Text Available
2006-09-01
DESIGN, IMPLEMENTATION AND TESTING OF ... - LAMBDA - NASA
FIG. 4. Power Spectral Density of the MAP W11 radiometer. The red and black traces are the power spectral density measurements of the two detectors on the ...
Energy Technology Data Exchange (ETDEWEB)
To study the biogeochemical behaviour, mobility and transport of trace metals in seawater (Se, Mo, Cd, Pb, Hg, Cu, Co, Fe, Ni, Zn), in suspended particulate matter (Mo, Cd, Pb, Cu, Co, Fe, Ni, Zn, Al, Mn) and in sediments of the inner and outer coastal regions, samples were collected on 3 separate cruises during a one year period (Mai 1993 - April 1994) at 20 stations in the coastal area of Mecklenburg-Vorpommern. Standard hydrographic parameters, nutrients and dissolved oxygen were also measured. Priority was taken to establish the methods for the determination of molybdenum and selenium. To study the behaviour of these two elements in detail, longterm measurements were carried out weekly between January 1993 and June 1994 at the `Messsteg/Warnemuende`. Because of parallel measurements correlations to biological, chemical and hydrographic parameters have been tested. The total database is summarized in the Appendix. The results are presented in 30 figures and 13 ...
1995-04-01
Energy Technology Data Exchange (ETDEWEB)
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. This new method is a significant improvement over current approaches, with features including a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), trace chemical analysis of each distillate fraction, and a corrosivity assessment of each distillate fraction. In the present contribution, we present the application of the advanced distillation curve method to a bio-derived crude oil prepared from swine manure. One motivation behind the work was to precisely measure the distillation curve of the oil derived from swine manure with our advanced distillation apparatus and compare the bio-derived oil to traditional petroleum crude oils. Then, the information content of the bio-derived oil distillation was extended further with the composition-explicit ...
2008-11-15
Tropospheric sampling with aircraft
Energy Technology Data Exchange (ETDEWEB)
Aircraft constitute a unique environment which places stringent requirements on the instruments used to measure the concentrations of atmospheric trace gases and aerosols. Some of these requirements such as minimization of size, weight, and power consumption are general; others are specific to individual techniques. This review presents the basic principles and considerations governing the deployment of trace gas and aerosol instrumentation on an aircraft. An overview of common instruments illustrates these points and provides guidelines for designing and using instruments on aircraft-based measurement programs.
1991-03-01
Content of long-lived radionuclides in the moss cover of the eastern-Ural radioactive trace region
Energy Technology Data Exchange (ETDEWEB)
This study examines the extent of radioactive pollution of moss cover of forest communities of the Kamenskii district of the Sverdlovsk region. This area contains the periphery section of the Eastern-Ural Radioactive Trace, formed as a result of the Kyshtymskii accident. Mosses do not release radionuclides for a long time, making them a biological indicator of radioactive environmental pollution and making them useful for radioecological monitoring. 14 refs., 2 figs., 1 tab.
1995-07-01
Trace metal characterization of the U-Al matrix by atomic spectroscopy
International Nuclear Information System (INIS)
Uranium-aluminum alloys with a significant enrichment of uranium with "2"3"3U or "2"3"5U serve as nuclear fuels in research reactors. The quality assurance of this fuel requires, among other things, precise knowledge that all trace metal constituents that affect neutron economy, fuel integrity, and fuel fabrication process parameters are well within the specification limits. Trace metal characterization of "2"3"5U-Al alloy has been carried out by atomic spectrometry. The trace metal constituents of interest are grouped into common metals (silver, boron, calcium, cadmium, cobalt, chromium, copper, iron, magnesium, manganese, molybdenum, sodium, nickel, lead, silicon, tin, titanium, vanadium, tungsten, and zinc) and lanthanides (cerium, dysprosium, europium, gadolinium, holminium, lutetium, samarium, and terbium). The elements yttrium and zirconium are grouped with the latter in view of the chemical separation procedure used. ...
International Nuclear Information System (INIS)
Application of greenwaste compost to brownfield land is increasingly common in soil and landscape restoration. Previous studies have demonstrated both beneficial and detrimental effects of this material on trace element mobility. A pot experiment with homogenised soil/compost investigated distribution and mobility of trace elements, two years after application of greenwaste compost mulch to shallow soils overlying a former alkali-works contaminated with Pb, Cu and As (#approx#900, 200 and 500 mg kg"-"1, respectively). Compost mulch increased organic carbon and Fe in soil pore water, which in turn increased As and Sb mobilization; this enhanced uptake by lettuce and sunflower. A very small proportion of the total soil trace element pool was in readily-exchangeable form (<0.01% As, <0.001% other trace elements), but the effect of compost on behaviour of metals was variable and ambiguous. It is ...
2010-05-01
Environmental trace gas analysis by proton-transfer-reaction mass spectrometry (PTR-MS)
International Nuclear Information System (INIS)
The work presented here demonstrates the ability of proton-transfer-reaction mass spectrometry (PTR-MS) to perform fast-response measurements of volatile organic compounds (VOCs) (including methanol, acetonitrile, acetaldehyde, acetone, PAN-type compounds, alpha- and beta-pinene, nopinone and pinonaldehyde) at the pptv level and its versatile applicability in the field of environmental trace gas analysis. Laboratory and field experiments including various calibration techniques and intercomparisons with other measurement techniques such as gas chromatography, atmospheric pressure chemical ionization and Fourier transformation infrared spectroscopy were performed providing a first characterization of the PTR-MS instrument performance (sensitivity, detection limit, precision, accuracy). Typically a detection limit (S/N=2) of 50 pptv for a 10 s signal integration time, a precision of 5 % and an accuracy in the range between 10 and 25 % were ...
Half-period optical pulse generation using a free-electron laser
Energy Technology Data Exchange (ETDEWEB)
Recently there has been growth, in interest in non-equilibrium interaction of half-period long optical pulses with matter. To date the optical pulses have been produced by chopping out a half-period long segment from a longer pulse using a semiconductor switch driven by a femtosecond laser. In this paper we present new methods for producing tunable ultra-short optical pulses as short as half an optical period using a free-electron laser driven by electron bunches with a duration a fraction of an optical period. Two different methods relying on the production of coherent spontaneous emission will be described. In the first method we show that when a train of ultra-short optical pulses as short as one half period. We present calculations which show that the small signal gain is unimportant in the early stages of radiation build up in the cavity when the startup process is dominated by coherent spontaneous emission. To support our proposed method ...
1995-12-31
The concentration and distribution of a soil fumigant in the subsurface of field plots are two key factors in the determination of the fumigant efficacy. Subsurface concentrations of the biologically active compounds cis- and trans-1,3-dichloropropene (1,3-D) and chloropicrin (CP) were determined in soil at two adjacent injection traces and midpoint between the two traces in plastic-covered field beds after injection of the fumigant Telone C35 by conventional chisels or by a coulter rig (Avenger coulters). Two of the four beds were covered with metallic polyethylene film (MPE) and the remaining two were covered with virtually impermeable film (VIF). Three hours after chisel injection, concentrations of the three compounds at the two adjacent injection traces in the two beds were highly variable. Large concentrations of the compounds were detected at the side traces, whereas the compounds were not ...
2007-06-02
Direct Comparison of the X-Ray Emission and Absorption of Cerium Oxide
Energy Technology Data Exchange (ETDEWEB)
Bremstrahlung Isochromat Spectroscopy (BIS). The XES spectra were collected using a Specs electron gun for the excitation and the XES 350 grating monochromator and channel plate system from Scienta as the photon detection. Spectra were collected in 'normal mode,' where the electron gun kinetic energy (KE) and the energy position of the center of the channel plate were both fixed and the energy distribution in the photon (hv) spectrum was derived from the intensities distributed across the channel plate detector in the energy dispersal direction. The polycrystalline Ce sample was oxidized by exposure to air at ambient pressures. After introduction to the ultra-high vacuum system, the oxidized sample was bombarded with Ar, to clean the topmost surface region and stabilize the surface and near surface regions. Although CeO{sub 2} would be the thermodynamically preferred composition in an oxygen rich environment, the combination of a vacuum ...
2010-11-24
Energy Technology Data Exchange (ETDEWEB)
Some hypo-stoichiometric Zr-based Laves phase alloys were prepared and studied from a viewpoint of discharge capacity for electrochemical application. After careful alloy design of ZrMn{sub 2}-based hydrogen storage alloys through changing their stoichiometry while substituting or adding some alloying elements, the Zr(Mn{sub 0.2}V{sub 0.2}Ni{sub 0.6}){sub 1.8} alloy reveals relatively good properties with regard to hydrogen storage capacity, hydrogen equilibrium pressure and electrochemical discharge capacity. In order to improve the discharge capacity and rate-capability, Zr is partially replaced by Ti. The discharge capacity of Zr{sub 1-x}Ti{sub x}(Mn{sub 0.2}V{sub 0.2}Ni{sub 0.6}){sub 1.8} (x=0.0, 0.2, 0.3, 0.4, 0.6) alloy electrodes at 30 C reaches a maximum value and decreases as the Ti fraction increases. In view of electrochemical and thermodynamic characteristics, the occurrence of a maximal phenomenon of the electrochemical discharge capacity of the alloy is attributed to a ...
2000-08-10
Ultra-thin {sup 242m}Am fuel elements in nuclear reactors
Energy Technology Data Exchange (ETDEWEB)
There is a growing interest in using {sup 242m}Am as a nuclear fuel. The advantages of {sup 242m}Am as a nuclear fuel derive from the fact that {sup 242m}Am has the highest thermal fission cross section. The thermal capture cross section is relatively low and the number of neutrons per thermal fission is high. These nuclear properties make it possible to obtain nuclear criticality with ultra-thin fuel elements. The possibility of having ultra-thin fuel elements enables the use of these fission products directly, without the necessity of converting their energy to heat, as is done in conventional reactors. There are three options of using such highly energetic and highly ionized fission products. - Using the fission products themselves for ionic propulsion. - Using the fission products in an MHD generator, in order to obtain electricity directly. - Using the fission products to heat a gas up to a high temperature for propulsion purposes. In this ...
2000-12-01
Ultra-high pressure water jet: Baseline report
International Nuclear Information System (INIS)
The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU's evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky trademark pump feeds water to a lance that directs the high pressure water at the surface to be removed. The safety and health evaluation during the testing demonstration focused on two main areas of exposure. These were dust and noise. The dust exposure was found to be minimal, which would be expected due to the wet environment inherent in the technology, but noise exposure was at a significant level. Further testing for noise is recommended because of ...
1997-07-01
Phantom and animal imaging studies using PLS synchrotron X-rays
Ultra-high resolution radiographs can be obtained using synchrotron X-rays. A collaboration team consisting of K-JIST, POSTECH and YUMC has recently commissioned a new beamline (5C1) at Pohang Light Source (PLS) in Korea for medical applications using phase contrast radiology. Relatively simple image acquisition systems were set up on 5C1 beamline, and imaging studies were performed for resolution test patterns, mammographic phantom, and animals. Resolution test patterns and mammographic phantom images showed much better image resolution and quality with the 5C1 imaging system than the mammography system. Both fish and mouse images with 5C1 imaging system also showed much better image resolution with great details of organs and anatomy compared to those obtained with a conventional mammography system. A simple and inexpensive ultra-high resolution imaging system on 5C1 beamline was successfully implemented. The authors were able to acquire ...
2001-01-01
Energy Technology Data Exchange (ETDEWEB)
In this paper, we propose to characterize boron transient enhanced diffusion (TED) for processes currently used for P{sup +}/N ultra-shallow junctions (USJ) fabrication. Indeed, the fundamental understanding of boron diffusion for low energy boron implantation is mandatory to evaluate the scalability of such processes for the coming complementary metal-oxide-semiconductor (CMOS) transistor generations. In these experiments, we characterize the boron anomalous diffusion, thanks to boron buried marker-layers obtained by epitaxial growth. B{sup +} and BF{sub 2}{sup +} ultra-low energy (ULE) implantations and plasma doping (PLAD) using BF{sub 3} as precursor gas are carried out to compare the two techniques used for advanced USJ fabrication. Boron diffusion behaviors are analyzed via secondary ion mass spectrometry for annealing at 700 deg. C for 5 min and 15 min. Finally this paper brings some physical insights explaining the technological benefit ...
2005-08-01
International Nuclear Information System (INIS)
In this paper, we propose to characterize boron transient enhanced diffusion (TED) for processes currently used for P"+/N ultra-shallow junctions (USJ) fabrication. Indeed, the fundamental understanding of boron diffusion for low energy boron implantation is mandatory to evaluate the scalability of such processes for the coming complementary metal-oxide-semiconductor (CMOS) transistor generations. In these experiments, we characterize the boron anomalous diffusion, thanks to boron buried marker-layers obtained by epitaxial growth. B"+ and BF_2"+ ultra-low energy (ULE) implantations and plasma doping (PLAD) using BF_3 as precursor gas are carried out to compare the two techniques used for advanced USJ fabrication. Boron diffusion behaviors are analyzed via secondary ion mass spectrometry for annealing at 700 deg. C for 5 min and 15 min. Finally this paper brings some physical insights explaining the technological benefit coming from PLAD ...
2005-08-01
Energy Technology Data Exchange (ETDEWEB)
The effects of gate and drain bias stresses on thin film transistors fabricated in polysilicon films crystallized using the advanced sequential lateral solidification excimer laser annealing (SLS ELA) process, which yields very elongated polysilicon grains and allows the fabrication of TFTs without grain boundary barriers to current flow, are investigated as a function of the active layer thickness and of the TFT orientation relative to the grains. The application of hot carrier stress, with a condition of V{sub GS} = V{sub DS}/2, was determined to induce threshold voltage, subthreshold swing and transconductance degradation for TFTs in thicker polysilicon films and the associated stress-induced increase in the active layer trap density was evaluated. However, this device degradation was drastically reduced for TFTs fabricated in ultra-thin films. Furthermore, the application of the same stress condition to TFTs oriented vertically to the elongated grains resulted ...
2005-01-01
International Nuclear Information System (INIS)
The effects of gate and drain bias stresses on thin film transistors fabricated in polysilicon films crystallized using the advanced sequential lateral solidification excimer laser annealing (SLS ELA) process, which yields very elongated polysilicon grains and allows the fabrication of TFTs without grain boundary barriers to current flow, are investigated as a function of the active layer thickness and of the TFT orientation relative to the grains. The application of hot carrier stress, with a condition of V_G_S = V_D_S/2, was determined to induce threshold voltage, subthreshold swing and transconductance degradation for TFTs in thicker polysilicon films and the associated stress-induced increase in the active layer trap density was evaluated. However, this device degradation was drastically reduced for TFTs fabricated in ultra-thin films. Furthermore, the application of the same stress condition to TFTs oriented vertically to the elongated grains resulted in ...
2005-01-01
Development of a fine and ultra-fine group cell calculation code SLAROM-UF for fast reactor analyses
International Nuclear Information System (INIS)
A cell calculation code SLAROM-UF has been developed for fast reactor analyses to produce effective cross sections with high accuracy in practical computing time, taking full advantage of fine and ultra-fine group calculation schemes. The fine group calculation covers the whole energy range in a maximum of 900-group structure. The structure is finer above 52.5 keV with a minimum lethargy width of 0.008. The ultra-fine group calculation solves the slowing down equation below 52.5 keV to treat resonance structures directly and precisely including resonance interference effects. Effective cross sections obtained in the two calculations are combined to produce effective cross sections over the entire energy range. Calculation accuracy and improvements from conventional 70-group cell calculation results were investigated through comparisons with reference values obtained with continuous energy Monte Carlo calculations. It was confirmed that ...
2006-08-01
The role of water and oxygen impurities on ozone production in a negative corona discharge of CO_2
International Nuclear Information System (INIS)
The production of ozone in a negative corona discharge fed by carbon dioxide with embedded traces of oxygen and water has been studied. The presence of traces of oxygen in both pure and dry CO_2 leads to an increase in nascent ozone concentrations. In contrast, traces of water vapour (0-800 ppm) are shown to rapidly suppress ozone concentrations with the largest decreases being observed at lowest gas pressures in the discharge (300 Torr). The presence of water vapour did not considerably affect the electrical properties of negative dc corona suggesting that a chemical process is responsible for the ozone loss. We have shown that the addition of water up to a concentration of 1500 ppm has only a marginal effect on the processes of ozone formation but the catalytic cycle of ozone destruction involving OH radicals can be the reason for observed decrease in the total ozone concentration with increasing water concentration.
2007-11-07
Energy Technology Data Exchange (ETDEWEB)
The impact of the azimuthal wave refraction in the middle atmosphere on the distribution of gravity wave amplitudes, propagation azimuths, and other wave parameters is investigated using a numerical ray-tracing model of gravity wave propagation through a representative zonal mean reference model of geostrophic winds and temperature in the middle atmosphere. Simulations are first performed with only a single type of gravity wave to help explain some important effects which occur during the refraction process. Then, a multiray simulation is performed which traces a crude spectrum of waves from different altitudes through the atmosphere for every month of a climatological year. The simulated wave climatologies are compared with observations. 108 refs.
1992-10-01
Grating cloaks are a variation of dielectric carpet (or ground- plane) cloaks. The latter were introduced by Li and Pendry. In contrast to the numerical work involved in the quasi-conformal carpet cloak, the refractive-index profile of a conformal grating cloak follows a closed and exact analytical form. We have previously mentioned that finite-size conformal grating cloaks may exhibit better cloaking than usual finite-size carpet cloaks. In this letter, we directly visualize their performance using photorealistic ray-tracing simulations. We employ a Newtonian approach that is advantageous compared to conventional ray tracing based on Snell's law. Furthermore, we quantify the achieved cloaking quality by computing the cross-correlations of rendered images. The cross-correlations for the grating cloak are much closer to 100% (i.e., ideal) than those for the Gaussian carpet cloak.
2010-01-01
Trace elements were extracted from a coal-fired power plant electrostatic precipitator ash with nitric acid, hydrochloric acid, citric acid, redistilled water, and ammonium hydroxide as extractants. Effluent waters at this plant were sampled to assess the elevation of trace element concentrations compared with intake waters. The results showed a positive correlation between those elements most extractable by water (B, F, Mo, and Se) or acid (As, B, Cd, F, Mo, and Se) and those elements most elevated in effluent waters (As, B, F, Mo, and Se).
1977-10-01
Ultrashallow P{sup +}/N junction formation by plasma ion implantation
Energy Technology Data Exchange (ETDEWEB)
We investigated the electrical characteristics and the junction depth of ultra-shallow junctions formed by using the plasma-doping method. Compared with ultra-low energy boron-ion implantation at 500 eV, the junctions formed with the plasma-doping process exhibited shallow junction depths and low sheet resistances. The junction depths of the plasma-doped samples were 150 A and 330 A after annealing for 10 s at 900 .deg. C and 950 .deg. C, respectively. For the same junction depth, the sheet resistance of the B{sub 2}H{sub 6} plasma-doped sample was an order of magnitude less than that of the 500-eV B-ion implanted sample. Cross-sectional transmission electron microscopy and deep level transient spectroscopy showed that the defects formed by the B{sub 2}H{sub 6} plasma-doping process could be removed by annealing at 950 .deg. C for 10 s. The scaling of metal-oxide-semiconductor field-effect-transistor (MOSFET) device channel lengths for ...
2000-12-01
Ultrashallow P"+/N junction formation by plasma ion implantation
International Nuclear Information System (INIS)
We investigated the electrical characteristics and the junction depth of ultra-shallow junctions formed by using the plasma-doping method. Compared with ultra-low energy boron-ion implantation at 500 eV, the junctions formed with the plasma-doping process exhibited shallow junction depths and low sheet resistances. The junction depths of the plasma-doped samples were 150 A and 330 A after annealing for 10 s at 900 .deg. C and 950 .deg. C, respectively. For the same junction depth, the sheet resistance of the B_2H_6 plasma-doped sample was an order of magnitude less than that of the 500-eV B-ion implanted sample. Cross-sectional transmission electron microscopy and deep level transient spectroscopy showed that the defects formed by the B_2H_6 plasma-doping process could be removed by annealing at 950 .deg. C for 10 s. The scaling of metal-oxide-semiconductor field-effect-transistor (MOSFET) device channel lengths for high-speed application ...
2000-12-01
XRF analysis of rock and sediment using standard rock samples
Energy Technology Data Exchange (ETDEWEB)
A simple and rapid method is described for the determination of major and trace elements in rock and sediment samples by wavelength dispersive XRF. Sample measured were made from cellulose powder pressed into 4 cm diameter aluminium ring 0.4 t cm/sup -2/, and then 1 g of powdered sample (0.08 g cm/sup -2/) was placed on the disk and repressed at 1.6 t cm/sup -2/. X-ray measurements were performed for total XRF intensity (I/sub p/) at the characteristic line of each element and background intensity (I/sub b/) in vicinity of the line. The correction of matrix effect was achieved by X-ray intensity ratio of peak to background for each element. Eight standard rock samples from Geological Survey of Japan were used as standard materials, and linear calibration curves were obtained by the plot of I/sub p/ - I/sub b/ vs. concentration for Ca, Na and Pb and by the plot of I/sub p//I/sub b/ ratio vs. concentration for Si, Fe, Ti, K, P, Cl, Cr, Mn, Ni, Cu, Zn, Pb, Sr and Ba, ...
1987-03-01
XRF analysis of rock and sediment using standard rock samples
International Nuclear Information System (INIS)
A simple and rapid method is described for the determination of major and trace elements in rock and sediment samples by wavelength dispersive XRF. Sample measured were made from cellulose powder pressed into 4 cm diameter aluminium ring 0.4 t cm"-"2, and then 1 g of powdered sample (0.08 g cm"-"2) was placed on the disk and repressed at 1.6 t cm"-"2. X-ray measurements were performed for total XRF intensity (I_p) at the characteristic line of each element and background intensity (I_b) in vicinity of the line. The correction of matrix effect was achieved by X-ray intensity ratio of peak to background for each element. Eight standard rock samples from Geological Survey of Japan were used as standard materials, and linear calibration curves were obtained by the plot of I_p - I_b vs. concentration for Ca, Na and Pb and by the plot of I_p/I_b ratio vs. concentration for Si, Fe, Ti, K, P, Cl, Cr, Mn, Ni, Cu, Zn, Pb, Sr and Ba, respectively. The relative standard ...
Energy Technology Data Exchange (ETDEWEB)
(-)-N6-(R-4-Hydroxyphenylisopropyl)adenosine (HPIA) was iodinated with NaI and trace /sup 125/I. Mono- and diiodinated reaction products and the starting material were separated by high pressure liquid chromatography and the structures of the reaction products were verified by NMR. (-)-N6-(R-Phenylisopropyl)adenosine (PIA), IHPIA, and I2HPIA decreased rat atrial contractility with ED50 values of 24, 28, and 33 nM, respectively. The contractile effects of these compounds were competitively blocked by theophylline (KI . 7.9 microM), but were not affected by adenosine deaminase. IHPIA also inhibited (-)isoproterenol-stimulated cyclic AMP accumulation in adipocytes with an ED50 (10 nM) and to an extent (83%) nearly identical to PIA. (/sup 125/I)HPIA prepared using carrier-free /sup 125/I bound to adenosine receptors on membranes from rat cerebral cortex, adipocyte ghosts, and heart ventricles. Binding was inhibited stereospecifically by PIA and by other adenosine ...
1984-11-01
International Nuclear Information System (INIS)
A novel continuous powder introduction microwave-induced plasma atomic emission spectrometry method (CPI-MIP-AES) has been developed for trace determination of metals in ground and tap water samples after preconcentration on activated carbon. The experimental setup consisted of integrated rectangular cavity TE_1_0_1 and vertically positioned plasma torch. The technical arrangement of the sample introduction system has been designed based on the fluidized bed concept. The satisfactory signal stability required for sequential analysis was attained owing to the vertical plasma configuration, as well as the plasma gas flow rate compatibility with sample introduction flow rate. The elements of interest (Cd, Cu, Cr, Fe, Mn, Pb, Zn) were preconcentrated in a batch procedure at pH 8-8.5 after addition of activated carbon and then, after filtering and drying of the activated carbon suspension, introduced to the MIP by the CPI system. An enrichment ...
2005-03-31
Energy Technology Data Exchange (ETDEWEB)
Dunaliella salina cells were pulse-labeled for 2 min with (/sup 14/C)palmitic acid, (/sup 14/C)oleic acid, or (/sup 14/C)lauric acid in order to trace the pathway of galactolipid biosynthesis and desaturation. Through the use of high performance liquid chromatography it was possible to follow the movement of radioactivity through many individual molecular species of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) for periods of 24 h and, in some cases, as much as 120 h. Analysis of the fatty acid fluxes permitted us to refine current views regarding biosynthesis of the predominantly prokaryotic galactolipids. The initial D. salina MGDG molecular species, containing paired oleate and palmitate (18:1/16:0), can follow two metabolic routes. If the palmitoyl chain is desaturated to 16:1, the resulting 18:1/16:1 MGDG is subject to rapid further desaturation to varying degrees, and a part of these products is subsequently ...
1987-06-05
Eight of 100 normotensive children who had pyelonephritic scarring secondary to urinary infection and vesicoureteric reflux were found in an earlier study to have increased plasma renin activity (PRA). Because the risk of these patients becoming hypertensive is between 10% and 20% and because renin activity may play a part in the pathogenesis of the hypertension, PRA and blood pressure were studied in 98 of the original group after five years of follow up. Two patients could not be traced, and other factors that might influence blood pressure or PRA led us to exclude 13 others, 10 of whom were girls taking oral hormonal contraceptives. Increased PRA was found in 11 of the remaining 85 patients but not in five of the eight patients with increased PRA in the first study. Of eight children identified as hypertensive in the follow up study, only three had had increased PRA five years previously. In normal children PRA decreases with age. In the initial study this ...
1987-07-01
Enrichment of trace cadmium by soybean protein for the analysis by atomic absorption method
International Nuclear Information System (INIS)
A method for enrichment of the ppb level of cadmium in water by using the coagulation of soybean protein by adding acids or its complex-forming character with heavy metal ions was investigated. After adding fixed amounts of soybean milk and 2% sodium diethyldithiocarbamate(DDTC) aqueous solution and a suitable amount of delta-gluconic lactone (delta-GL) to a sample solution, the mixture was heated to boiling in order to coagulate the protein. The coagulum(soybean curd) was separated from the suspension by centrifugation and burned to ashes with a low temperature plasma asher. Then the cadmium enriched in it was determined by atomic absorption spectrometry. Various factors such as the pH of the sample solution, the amounts of soybean milk and the collection additives, and the concentration of NaCl in the sample solution on the recovery of cadmium were examined systematically. The best recovery was obtained under the following conditions: To a certain amount of sample solution were added ...
1975-01-01
International Nuclear Information System (INIS)
Nuclear analytical techniques were applied to determine the elemental compositions of suspended and bottom sediments, collected at different sites in Haiphong harbor area (North Viet nam). The study was aimed at: 1/Understanding the origin of the sediment filling up the access channel and causing large expenditures for dredging operations. 2/Determining the background concentrations of trace elements in sediment. This would allow to detect in the future any pollution caused by the discharge of industrial wastes in the water due to the growing industrialization of the area. 3/Identifying the elements, which can be served as activatable tracers in sediment transport studies. The results obtained for the concentrations of nearly 30 elements show rather similar elemental compositions, reflecting a common origin of the sediments taken from different locations in the harbour area. The results could not allow to identify the pathway of the sediment transported to and ...
1992-03-09
International Nuclear Information System (INIS)
The concentration of trace elements in brain sections was measured by synchrotron radiation X-ray fluorescence. The relative concentration was calculated by means of the normalization of Compton scattering intensity approximately 22 keV, after the normalization for collecting time of X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate film for supporting sample. Furthermore, the statistical evaluation of the element distribution in various regions of the brain sections of the 20-day-old rats was tested. For investigating the distribution of elements in the brain of iodine deficient rats, Wistar rats were fed with iodine deficient diet and deionized water (ID group). The rats were fed the same iodine deficient diet, but drank KIO_3 solution as control (CT group). The results showed that the contents of calcium (Ca) in thalamus (TH) and copper (Cu) and iron (Fe) in cerebral cortex (CX) of ID rats were ...
2004-02-27
Development of a stable cobalt-ruthenium Fisher-Tropsch catalyst. Final report
Energy Technology Data Exchange (ETDEWEB)
The reverse micelle catalyst preparation method has been used to prepare catalysts on four supports: magnesium oxide, carbon, alumina- titania and steamed Y zeolite. These catalysts were not as active as a reference catalyst prepared during previous contracts to Union Carbide Corp. This catalyst was supported on steamed Y zerolite support and was impregnated by a pore-filling method using a nonaqueous solvent. Additional catalysts were prepared via pore- filling impregnation of steamed Y zeolites. These catalysts had levels of cobalt two to three and a half times as high as the original Union Carbide catalyst. On a catalyst volume basis they were much more active than the previous catalyst; on an atom by atom basis the cobalt was about of the same activity, i.e., the high cobalt catalysts` cobalt atoms were not extensively covered over and deactivated by other cobalt atoms. The new, high activity, Y zerolite catalysts were not as stable as the earlier Union Carbide catalyst. However, ...
1995-02-01
Energy Technology Data Exchange (ETDEWEB)
As the jump from 2D to 3D, seismic exploration lives a new revolution with the use of converted PS waves. Indeed PS converted waves are proving their potential as a tool for imaging through gas; lithology discrimination; structural confirmation; and more. Nevertheless, processing converted shear data and in particular determining accurate P and S velocity models for depth imaging of these data is still a challenging problem, especially when the subsurface is anisotropic. To solve this velocity model determination problem we propose to use reflection travel time tomography. In a first step, we derive a new approximation of the exact phase velocity equation of the SV wave in anisotropic (TI) media. This new approximation is valid for non-weak anisotropy and is mathematically simpler to handle than the exact equation. Then, starting from an isotropic reflection tomography tool developed at Lt-'P, we extend the isotropic bending ray tracing method to the ...
2001-12-01
A PIXE/PIGE study of gold mineralisation in lateritic terrain, Tanami Desert, Australia
Energy Technology Data Exchange (ETDEWEB)
Proton induced X-ray and {gamma}-ray emission (PIXE/PIGE) have been used to analyze major and trace elements in a suite of 140 core samples from around of the Jim`s Find South gold anomaly in the Tanami desert, located in heavily weathered terrain. Simultaneous analyses were obtained for 30 elements, ranging in atomic number from {sup 3}Li to {sup 90}Th. The method was chosen because of its speed and the wide range of determination, its flexibility, precision and low detection limits. The regolith powder samples were treated by hot aqua regia before making them into pills. The PIXE/PIGE data of the acid insoluble residue give three factor analysis clusters. The first cluster comprises the elements F, Al, K, V, Mn, Fe, Ga, Rb, W and Au and is essentially related to sericitic wallrock alteration. The second cluster consists of Ti, As, Y, Zr, and Nb and is largely related to resistant minerals. The third cluster consists of Na, Ca and Sr and is ...
1997-12-31
Theoretical Standard Model Rates of Proton to Neutron Conversions Near Metallic Hydride Surfaces
The process of radiation induced electron capture by protons or deuterons producing new ultra low momentum neutrons and neutrinos may be theoretically described within the standard field theoretical model of electroweak interactions. For protons or deuterons in the neighborhoods of surfaces of condensed matter metallic hydride cathodes, such conversions are determined in part by the collective plasma modes of the participating charged particles, e.g. electrons and protons. The radiation energy required for such low energy nuclear reactions may be supplied by the applied voltage required to push a strong charged current across a metallic hydride surface employed as a cathode within a chemical cell. The electroweak rates of the resulting ultra low momentum neutron production are computed from these considerations.
2006-01-01
British Library Electronic Table of Contents (United Kingdom)
Tailor die quenching in the hot stamping of quenchable steel sheets was developed to produce ultra-high strength steel formed parts having strength distribution. Local portions of the heated sheet were quenched by holding grooved tools at the bottom dead centre during the stamping. Non-contact portions were generated in the sheet by grooving the tools, and thus the strength in the contact portions is high owing to the quenching and that in the non-contact portions is low owing to the lack of the quenching. Hat-shaped products having a tensile strength of approximately 1.5GPa only at four corners were formed.
2010-01-01
Simulation of the filtration mechanism of hyaluronic acid in total knee prosthesis
Energy Technology Data Exchange (ETDEWEB)
Polyethylene (UHMWPE) wear in current knee prosthesis causes prosthesis loosening after no more than 15 years. In this work, a steady state one-dimensional lubrication model with non- Newtonian fluid, porous elastic layer on tibial component, ultra-filtration mechanism of fluid and some features of the surface roughness is studied through a numerical technique based on the Finite Element Method. The results show that the UHMWPE stiffness makes difficult the lubrication mechanism of the artificial joint and promotes abrasive and fatigue wear. Nevertheless, the use of compliant porous materials on the tibial component could reduce friction and wear. Moreover, the ultra-filtration mechanism promotes efficiency on the joint.
2007-11-15
Mechanical properties and structure of low-alloy ultra-high strength steels
Energy Technology Data Exchange (ETDEWEB)
Mechanical properties of P-LDHA and V-ROL N steels of the Czech production are compared with other ultra-high strength steels produced in the world. The most important results can be summarized into following points: 1. Optimally heat treated P-LDHA steel exhibits substantially better strength characteristics then the V-ROL N steel. 2. Optimal tempering temperature of the P-LDHA steel is 300 C. 3. Basic mechanical properties of P-LDHA steel belong to the top of the UHS steels ranking and are well comparable with those of American 300 M steel. 4. In the low-cycle fatigue region, the P-LDHA steel exhibits slightly better fatigue resistance then the 300 M steel. On the other hand, the high-cycle fatigue resistance of 300 M steel is slightly better then that of the P-LDHA steel. (orig.)
2000-07-01
Hydrogen transport and embrittlement in 300 M and AerMet100 ultra high strength steels
Energy Technology Data Exchange (ETDEWEB)
This paper describes how hydrogen transport affects the severity of hydrogen embrittlement in 300 M and AerMet100 ultra high strength steels. Slow strain rate tests were carried out on specimens coated with electrodeposited cadmium and aluminium-based SermeTel 1140/962. Hydrogen diffusivities were measured using two-cell permeation and galvanostatic charging methods and values of 8.0 x 10{sup -8} and 1.0 x 10{sup -9} cm{sup 2} s{sup -1} were obtained for 300 M and AerMet100, respectively. A two-dimensional diffusion model was used to predict the hydrogen distributions in the SSR specimens at the time of failure. The superior embrittlement resistance of AerMet100 was attributed to reverted austenite forming around martensite laths during tempering.
2010-05-15
Development of Ultra-Fast Silicon Switches for Active X-Band High Power RF Compression Systems
Energy Technology Data Exchange (ETDEWEB)
We present the recent results of our research on the high power ultra-fast silicon RF switches. This switch is composed of a group of PIN diodes on a high purity silicon wafer. The wafer is inserted into a cylindrical waveguide under TE{sub 01} mode, performing switching by injecting carriers into the bulk silicon. Our current design uses a CMOS compatible process and the device was fabricated at SNF (Stanford Nanofabrication Facility). 300 ns switching time has been observed, while the switching speed can be improved further with 3-D device structure and faster driving circuit. Power handling capacity of the switch is at the level of 10 MW. The switch was designed for active X-band RF pulse compression systems--especially for NLC, but it is also possible to be modified for other applications and other frequencies.
2006-03-06
Design and fabrication of large ultra-thin PIN detector with membrane stress deviation
Energy Technology Data Exchange (ETDEWEB)
In this paper, the design of large thin PIN detector with a membrane stress avoidance configuration is proposed, and the related device fabrication process is developed. Ultra-thin PIN detector {approx} 1.13 cm{sup 2} in area is fabricated on a thin ( {approx} 35{mu}m) silicon membrane, and characterized. Detector performance improvement has been successfully demonstrated. With the membrane stress avoidance design, the improved detector exhibits a leakage of 6nA, which is at least 5 times lower than that of detector of identical junction area. The new detector features a full depleted capacitance of 110 pF, and a FWHM of 40.86 keV energy resolution for 5.486 MeV alpha particle spectrography.
2010-09-15
British Library Electronic Table of Contents (United Kingdom)
Bacterial cellulose produced by the gram-negative bacterium Gluconacetobacter xylinum was found to be an excellent native starting material for preparing shaped ultra-lightweight cellulose aerogels. The procedure comprises thorough washing and sterilization of the aquogel, quantitative solvent exchange and subsequent drying with supercritical carbon dioxide at 40 degreeC and 100 bar. The average density of the obtained dry cellulose aerogels is only about 8 mg cm-3 which is comparable to the most lightweight silica aerogels and distinctly lower than all values for cellulosic aerogels obtained from plant cellulose so far. SEM, ESEM and nitrogen adsorption experiments at 77 K reveal an open-porous network structure that consists of a comparatively high percentage of large mesopores and small...
2010-01-01
and streambed sediment samples 2-6. Graphs showing: 2. Cesium-137 profile in HOE core 3. PAH trends in Lake Houston cores 4. DDE trends in Lake Houston cores 5. Trends in six trace...
2011-08-27
The preparation of a `metal-free' nappy and its application to metabolic balances in children
UK PubMed Central (United Kingdom)
Disposable nappies (diapers) have been satisfactorily demineralized and used for the collection of excreta from infants and young children during mineral and trace metal balances. It was possible to...Full Text Available
1972-11-01
Sequence Reactivation in the Hippocampus is Impaired in Aged Rats
UK PubMed Central (United Kingdom)
The hippocampus is thought to coordinate memory consolidation by reactivating traces from behavioral experience when the brain is not actively processing new input. In fact, during slow-wave...Full Text Available
2008-07-30
Retrograde neuronal tracing with a deletion-mutant rabies virus
UK PubMed Central (United Kingdom)
We have constructed a deletion-mutant rabies virus encoding EGFP and find it to be an excellent tool for studying detailed morphology and physiology of neurons projecting to injection sites...Full Text Available
2007-01-01
UK PubMed Central (United Kingdom)
We use high-density single nucleotide polymorphism (SNP) genotyping microarrays to demonstrate the ability to accurately and robustly determine whether individuals are in a complex genomic DNA mixture....Full Text Available
2008-08-01
Optical System Assessment for Design: Numerical Ray Tracing in the Gaussian Pupil,
The continuing rapid increase in available computing power has not reduced the importance of efficient methods of optical system assessment for automatic lens design. On the contrary, the new capabilities simply show that truly automatic optical design wi...
1988-01-01
Numerical optimization of spherical variable-line-spacing grating X-ray spectrometers
UK PubMed Central (United Kingdom)
Operation of an X-ray spectrometer based on a spherical variable-line-spacing (VLS) grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and...Full Text Available
2011-03-01
UK PubMed Central (United Kingdom)
A strain of Neurospora crassa was isolated by training the mould to grow on media containing high concentrations of Co2+. This strain, the CoR strain, exhibited...Full Text Available
1973-04-01
UK PubMed Central (United Kingdom)
We present a software system that computationally reproduces biochemical radioisotope-tracer experiments. It consists of three main components: A mapping database of substrate-product atomic correspondents...Full Text Available
2003-11-01
Energy Technology Data Exchange (ETDEWEB)
In the course of the research project 'Investigations of trace element concentrations in coal seams with different mineral groups', 31 seam coals of the Ruhr Carboniferous were analysed in order to determine the bending of 14 coal-relevant trace elements to the mineral groups and/or minerals of the coals. Products with different ash content were produced by fluctuation of the seam coals in a laboratory cell. The raw coals and fluctuation component products were analyzed chemically and mineralogically in order to get a quantitative raw material characterisation of the sampled material. Particular interest is taken in the chemical and non-ecological composition of the mineral as ash carrier in the coal and the fluctuation component products, as well as in trace element control. (orig./EF).
1992-01-01
Genome-Wide Transcriptional Response of Chemostat-Cultured Escherichia coli to Zinc
UK PubMed Central (United Kingdom)
Zinc is an essential trace metal ion for growth, but an excess of Zn is toxic and microorganisms express diverse resistance mechanisms. To understand global bacterial responses to excess Zn, we conducted...Full Text Available
2005-02-01
Evolution of macromolecular import pathways in mitochondria, hydrogenosomes and mitosomes
UK PubMed Central (United Kingdom)
All eukaryotes require mitochondria for survival and growth. The origin of mitochondria can be traced down to a single endosymbiotic event between two probably prokaryotic organisms. Subsequent evolution...Full Text Available
2010-03-12
UK PubMed Central (United Kingdom)
Linking biological samples found at a crime scene with the actual crime event represents the most important aspect of forensic investigation, together with the identification of the sample donor. While...Full Text Available
2010-09-01
Effect of NAD+ on Malate Oxidation in Intact Plant Mitochondria 1
UK PubMed Central (United Kingdom)
Potato tuber mitochondria oxidizing malate respond to NAD+ addition with increased oxidation rates, whereas mung bean hypocotyl mitochondria do not. This is traced to a low endogenous content...Full Text Available
1980-08-01
UK PubMed Central (United Kingdom)
BackgroundThe rate of emergence of human pathogens is steadily increasing; most of these novel agents originate in wildlife. Bats, remarkably, are the natural reservoirs of many...Full Text Available
Bioaccumulation and toxicity of selenium compounds in the green alga Scenedesmus quadricauda
UK PubMed Central (United Kingdom)
BackgroundSelenium is a trace element performing important biological functions in many organisms including humans. It usually affects organisms in a strictly dosage-dependent manner...Full Text Available
Energy Technology Data Exchange (ETDEWEB)
Instrumental neutron activation analysis (INAA) followed by gamma-ray spectrometry was used to determine the concentrations of As, Ca, Co, Cr, Cu, Eu, Fe, K, La, Mg, Mn, Mo, Na, Pr, Sb, Se, Th, U, V and Z, in 82 leaf samples belonging to two cultivars of pigeonpea (Cajanus cajan (L.) Millsp). Pigeonpea, an easy cultivation legume species, probably originated from Africa and adapted to brazilian conditions, is a very promising and unconventional source of food, mainly to the grain production intended for human feeding, and that even can be used in flour products. It is an excellent proteic supplement for ruminants, due to its large potential of forage production and its high nutritive value, or in addition it can be used in the recuperation of exhausting soils either by means of its utilization as green manure or by taking free Nitrogen from the atmosphere to produce nitrates which can be utilized by the plants. However, in spite of the several possibilities and ...
2001-07-01
Energy Technology Data Exchange (ETDEWEB)
The investigation of the petroleum contamination in marine organisms requires the trace level quantitative determination of indicative substances to be identified by a fingerprint of petroleum. Polymethylnaphthalene (PMN) and polymethylphenanthrene (PMP) were chosen because of their simple separation from a crude oil by means of an activated charcoal chromatography, their relatively high existence in aromatic compounds, and their persistence relative to other petroleum components in the tissue of oil contaminated marine organisms. The purpose of this paper is to present an activated charcoal chromatographic separation procedure of PMN and PMP in a crude oil and a trace level quantitative analytical method of them in marine organisms by mass fragmentography (MF).
1980-09-01
International Nuclear Information System (INIS)
A database has been compiled on human dietary intakes of trace elements by populations groups living in various countries. The main sources of information used were (1) publications in the open scientific literature, and (2) data submitted to the IAEA in response to a questionnaire. The database contains 1,758 intake values covering 35 elements and 47 countries. In this report the data are listed in various ways to facilitate identification of intake values for any specified country, element and population group. 4 refs, 5 tabs.
Determining surface profile from sequential interference patterns from a long trace profiler
Energy Technology Data Exchange (ETDEWEB)
The Long Trace Profiler (Takacs et al.) is a slope-measuring instrument which was introduced several years ago. Development of this instrument continues at Lawrence Berkeley Laboratory in improving both hardware design and software algorithms for turning the raw interference data (a sequence of intensity patterns) into properly interpreted representations of surface slope and height. This report presents a mathematical model of the interference pattern and methods of extracting the slope and height profile from such patterns. 9 refs.
1991-07-01
British Library Electronic Table of Contents (United Kingdom)
The concentrates of scattered organic matter???kerogen-like polymer, which is insoluble in acids and organic solvents???were isolated from rock samples taken at different depths from various stratigraphic units at the productive deposits of the Orenburg oil-gas condensate field using chemical methods. The chemical composition of the kerogen-like polymer and the concentrations of trace elements in it were studied. The regularities of evolutionary changes in the composition of the organic matter and the concentrations of trace elements in it in the order of the kerogen-like polymer and the following its consecutive derivatives were established: asphaltenes, ethanol-benzene tars, benzene tars, oils, and paraffins
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
High and ultra-high strength steels for pipelines are produced by properly handling the steel microstructure. The metallurgical principles involved in the microstructure control are presented, with emphasis on TMCP processing, that comprises conventional controlled rolling followed by accelerated cooling. (author)
2008-05-15
Energy Technology Data Exchange (ETDEWEB)
Conference abstract book contains seven sections: Plenary-4 abstracts; Chemical-9 abstracts; Radiation-7 abstracts; Ultra Low Doses and Medicine-6 abstracts; Biomedical-11 abstracts; Risk Assessment-5 abstracts and Poster Sessions-25 abstracts. Each abstract was provided by the author/presenter participating in the conference.
2002-05-28
New designs for Ultra High High-Power Single Transverse Mode Cw fibre lasers
International Nuclear Information System (INIS)
Overcoming the limiting constraints of stimulated Raman scattering (SRS) and stimulated Brilluoin scattering (SBS) poses serious fibre design challenges for increasing the output power of optical amplifiers and lasers. New fibre amplifier designs are proposed to break out of these limitations to reach several kWs CW powers. (Author)
2009-04-01
Nanophotonic components utilizing channel plasmon polaritons
Channel plasmon polaritons (CPPs) propagating along the bottom of subwavelength grooves cut into a metal surface were recently shown to exhibit strong confinement combined with low propagation loss, a feature that makes this guiding configuration very promising for the realisation of ultra-compact photonic components. Here, the results of our investigations of CPP guiding by V-grooves cut into gold are presented, demonstrating efficient large-angle bending and splitting of radiation as well as waveguide-ring resonators and Bragg grating filters.
2008-08-01
Method of defining features on materials with a femtosecond laser
Energy Technology Data Exchange (ETDEWEB)
The invention relates to a pulsed laser ablation method of metals and/or dielectric films from the surface of a wafer, printed circuit board or a hybrid substrate. By utilizing a high-energy ultra-short pulses of laser light, such a method can be used to manufacture electronic circuits and/or electro-mechanical assemblies without affecting the material adjacent to the ablation zone.
2006-05-23
In situ spectroscopic and corrosion studies of ultra-thin gradient plasma polymer layers on zinc
International Nuclear Information System (INIS)
By means of an audio frequency plasma polymerisation ultra-thin gradient plasma polymer layers were deposited on zinc and zinc-coated iron. The aim was to generate an interfacial polymeric layer which bonds to an oxidised metal as well as to a subsequently applied organic coating and acts as an interfacial barrier layer for ions and water. Surface modifications were done in an in situ plasma cell with infrared reflection absorption spectroscopy (IRRAS). The zinc surface was first activated by an oxygen plasma to provide a freshly oxidised and contamination free oxide surface. The intermediate stages of the surface reactions could be revealed. Carbon dioxide molecules as oxidation products adsorbed on the growing zinc oxide and were desorbed at a later stage. An organosilicon plasma polymer was deposited directly on top of the oxide layer from a hexamethyldisilane (HMDS) plasma. Afterwards a cyclohexene (CHEX)/hexamethyldisilane co-plasma polymer was deposited. The ...
2003-07-15
Determination of [sup 99]Tc in sea water at ultra low levels
Energy Technology Data Exchange (ETDEWEB)
A method based on the collection of [sup 99]Tc from 500 l sea water samples by anion exchange and further extraction of TcO[sub 4][sup -] into 5% triisooctylamine-xylene has been improved to include a decontamination factor 6.5x10[sup 5] for uranium. The detection limit for [sup 99]Tc is thereby reduced to 3 mBq/m[sup 3].
1994-01-20
A Theory of Laser Induced Nuclear Reaction in Single Atoms
International Nuclear Information System (INIS)
An 'electron-bridge' mechanism of nuclear reaction in an atom or ion by ultra-intense laser fields is presented. A preliminary estimate of the intensity dependence of the rate of disintegration reaction of deuteron nucleus in deuterium atom is made for 800 nm laser fields. For intensities below 5x1021 W/cm2, the rate of disintegration by the 'electron-bridge' mechanism is found to be small, but it rises sharply and becomes large already for ?1022 W/cm2.
2010-02-02
Energy Technology Data Exchange (ETDEWEB)
Pyrolysis and combustion of CH are investigated. In order to reduce the work required for the present combination of parameters, the following substances were selected: Hexachloroethane, hexachlorocyclohexane, hexachlorobenzene and hexachlorophene. The model substances were pyrolyzed or combusted in varying conditions, and the combustion or pyrolysis products were analyzed. Only the main products were of interest; trace components are important only as far as they may throw light on the reaction mechanisms. The furnace design resulted in incomplete combustion and pyrolysis reactions, so that products of all stages of combusition or pyrolysis were available for analysis. Reaction processes can be derived from the products. As an alternative to thermal treatment of refuse, biological degradation of chlorinated hydrocarbons was gone into. The efficiency of decomposition by microorganisms was to be compared with the efficiency of thermal ...
1993-07-01
Energy Technology Data Exchange (ETDEWEB)
Iodized oil has been used as a contrast agent in lymphangiography. One of the commercially available compounds is Lipidol Ultra-fluid(LUF) which contains 38% iodine by weight. Nakakuma et al(1979) reported that LUF was selectively retained in the hypervascular hepatocellular carcinoma when injected directly into the ligated hepatic artery. Since that time, it has been widely utilized in the detection as well as the therapeutic attempts of hepatocellular carcinoma, where it has been mixed with chemotherapeutic agents or labeled with radioactive I-131. Like all significant advances, the mechanism of lipid retention within the hepatocellular carcinoma is not clearly understood, and also there is a lack of information about the biodistribution and kinetics of I-131 Lipiodol. The apparent safety of this technique require confirmation. The present study was aimed to assess the biodistribution and kinetics of intraarterially injected I-131 Lipiodol and the histologic ...
1989-08-15
Modeling, Simulation Design and Control of Hybrid-Electric Vehicle Drives
Energy Technology Data Exchange (ETDEWEB)
Ohio State University (OSU) is uniquely poised to establish such a center, with interdisciplinary emphasis on modeling, simulation, design and control of hybrid-electric drives for a number of reasons, some of which are: (1) The OSU Center for Automotive Research (CAR) already provides an infrastructure for interdisciplinary automotive research and graduate education; the facilities available at OSU-CAR in the area of vehicle and powertrain research are among the best in the country. CAR facilities include 31,000 sq. feet of space, multiple chassis and engine dynamometers, an anechoic chamber, and a high bay area. (2) OSU has in excess of 10 graduate level courses related to automotive systems. A graduate level sequence has already been initiated with GM. In addition, an Automotive Systems Engineering (ASE) program cosponsored by the mechanical and electrical engineering programs, had been formulated earlier at OSU, independent of the GATE program proposal. The main objective of the ...
2005-09-30
Energy Technology Data Exchange (ETDEWEB)
This paper describes the modeling of horizontal steam generator with the TRACE code and calculation results of a loss-of-feedwater (LOF-10) experiment at the PACTEL facility. Parallel Channel Test Loop (PACTEL) is an integral test facility for a VVER-440 type nuclear reactor. The main objectives were to prepare a simulation model for its horizontal steam generator with the TRACE thermal hydraulic code and assess different modeling options of the code. PACTEL experiment LOF-10 was chosen for this assessment. The calculation results showed that TRACE is capable in simulating horizontal steam generator behavior both in steady state and during loss-of-feedwater transient. The phenomenon of heat transfer from primary to secondary side, steam superheating and flow reversal in the lowest heat exchange tubes were studied in detail. Different nodalization options were introduced. In the simulation of PACTEL loss-of-feedwater ...
2010-11-15
International Nuclear Information System (INIS)
This paper describes the modeling of horizontal steam generator with the TRACE code and calculation results of a loss-of-feedwater (LOF-10) experiment at the PACTEL facility. Parallel Channel Test Loop (PACTEL) is an integral test facility for a VVER-440 type nuclear reactor. The main objectives were to prepare a simulation model for its horizontal steam generator with the TRACE thermal hydraulic code and assess different modeling options of the code. PACTEL experiment LOF-10 was chosen for this assessment. The calculation results showed that TRACE is capable in simulating horizontal steam generator behavior both in steady state and during loss-of-feedwater transient. The phenomenon of heat transfer from primary to secondary side, steam superheating and flow reversal in the lowest heat exchange tubes were studied in detail. Different nodalization options were introduced. In the simulation of PACTEL loss-of-feedwater ...
2010-11-01
Masking of trace metal contaminants with citrate in the In-111 labeling of Mab-DTPA
International Nuclear Information System (INIS)
Tumor imaging using radioiodinated monoclonal antibodies (Mab) suffered from rapid in vivo deiodination. This problem can be circumvented by covalent attachment of a bifunctional chelating group to the Mab followed by chelation with a suitable cationic radionuclide such as In-111. Competition of trace metal contaminants with In-111 for chelating sites, however, is known to lower the labeling yield. Since commercially available reagents may be contaminated with other trace metal ions, the effect of trace metals on Mab-DTPA chelation and the possibility of masking the trace metal effect on the In-111 labeling of Mab-DTPA were, therefore, investigated. Labeling yield of 93% was obtained when 1 mg (20mg/ml) of Mab F(ab')/sub 2/-DTPA (protein to DTPA ratio of --1) was allowed to incubate with 3 mCi In-111 in 2 ml acetate buffer (0.5M, pH 5.5) for 30 min. The yield was drastically decreased to 13-76% when the ...
1985-06-02
VSP reverse-time migration using two-way nonreflection wave equation
Energy Technology Data Exchange (ETDEWEB)
VSP data are usually recorded in common-shot gather and contain less informations. It is difficult, therefore, to obtain good migration result by using conventional migration methods. Both inner interface reflections and interformational multiples can be removed by reverse-time migration with the use of two-way nonreflection wave equation: besides, boundary reflection in VSP can be eliminated using Clayton's absorption boundary condition. It is proved that reverse-time migration is able to improve migration quality. The imaging condition is still obtained by generalizing Claerbout's imaging principle and solving eikonal equation. This is a very practical wave equation migration method. This method is applicable to prestack VSP data, conventional multiple-offset shot gather and the simultaneous migration of VSP data and surface seismic data. Besides, it is adaptable to various velocity variations. Before applying the method to VSP data processing, one should finish the ...
1989-01-01
Separation of trace radionuclides by ion exchange in the presence of competing ions
International Nuclear Information System (INIS)
The performance of larger than bench scale ion exchange systems is evaluated by using solutions containing trace amounts of "1"3"7Cs, "8"5Kr, and "1"3"1I, and large amounts of either NaCl or Na_2HPO_4, H_3BO_3, and LiOH. The significant finding in this study is that the empirical rules of ionic selectivity of strong acid cation and strong base anion resins were followed by all ionic species, even though concentrations of some macrocomponents were nearly 10"6 times those of trace components. Other results of possible importance are the correlation between the instantaneous decontamination factor (DF) and the efficiency of column exchange capacity utilization, and the concept of time average decontamination factor (anti DF). The plot of anti DF vs. feed throughput will serve as a guide in determining when the feed should be discontinued in order to achieve a desired anti DF. Both of these correlations are derived from the breakthrough curves.
Ray Tracing Simulations of Weak Lensing by Large-Scale Structure
We investigate weak lensing by large-scale structure using ray tracing through N-body simulations. Photon trajectories are followed through high resolution simulations of structure formation to make simulated maps of shear and convergence on the sky. Tests with varying numerical parameters are used to calibrate the accuracy of computed lensing statistics on angular scales from about 1 arcminute to a few degrees. Various aspects of the weak lensing approximation are also tested. For fields a few degrees on a side the shear power spectrum is almost entirely in the nonlinear regime and agrees well with nonlinear analytical predictions. Sampling fluctuations in power spectrum estimates are investigated by comparing several ray tracing realizations of a given model. For survey areas smaller than a degree on a side the main source of scatter is nonlinear coupling to modes larger than the survey. We develop a method which uses this effect to estimate ...
2000-01-01
We propose the Particle Swarm Optimization (PSO) as an alternative method for locating periodic orbits in a three--dimensional (3D) model of barred galaxies. We develop an appropriate scheme that transforms the problem of finding periodic orbits into the problem of detecting global minimizers of a function, which is defined on the Poincar\\'{e} Surface of Section (PSS) of the Hamiltonian system. By combining the PSO method with deflection techniques, we succeeded in tracing systematically several periodic orbits of the system. The method succeeded in tracing the initial conditions of periodic orbits in cases where Newton iterative techniques had difficulties. In particular, we found families of 2D and 3D periodic orbits associated with the inner 8:1 to 12:1 resonances, between the radial 4:1 and corotation resonances of our 3D Ferrers bar model. The main advantages of the proposed algorithm is its simplicity, its ability to work using function ...
2005-01-01
OZONE PRODUCTION IN THE PHILADELPHIA URBAN AREA DURING NE-OPS 99
International Nuclear Information System (INIS)
As part of the 1999 NARSTO Northeast Oxidant and Particulate Study (NE-OPS) field campaign, the DOE G-1 aircraft sampled trace gases and aerosols in and around the Philadelphia metropolitan area. Twenty research flights were conducted between July 25 and August 11. The overall goals of these flights were to obtain a mechanistic understanding of O(sub 3) production; to characterize the spatial and temporal behavior of photo-oxidants and aerosols; and to study the evolution of aerosol size distributions, including the process of new particle formation. Within the NE-OPS program, other groups provided additional trace gas, aerosol, and meteorological observations using aircraft, balloon, remote sensing, and surface based instruments (Phillbrick et al., 2000). In this article we provide an overview of the G-1 observations related to O(sub 3) production, focusing on the vertical distribution of pollutants. Ozone production rates are calculated using ...
Assessment of the historical trace metal contamination of sediments in the Elizabeth River, Virginia
International Nuclear Information System (INIS)
Two sediment cores (Southern Branch, PC-1, and Western Branch, WB-2) were taken from the highly industrialized Elizabeth River, Virginia. The concentrations of trace metals cadmium, cobalt, chromium, copper, nickel, lead and zinc, major elements iron, manganese and aluminum, organic carbon content and the specific surface area of the sediments were determined in each of the cores. Down-core variations in metals varied significantly in each core with maximum contamination events occurring at different times in different portions of the river. In PC-1, maximum metal concentrations were seen after the appearance of "1"3"7Cs. In contrast, the highest levels in WB-2 occurred well before the appearance of "1"3"7Cs. Although stricter environmental regulations have caused a decrease in metal concentrations since the 1980s, the concentrations in the surface sediments of many trace metals were elevated to levels 2-5 times higher than the levels at the ...
2007-04-01
Materials used in new generation vehicles: supplies, shifts, and supporting infrastructure
Energy Technology Data Exchange (ETDEWEB)
The Partnership for a New Generation of Vehicles (PNGV) program intends to develop new designs for automobiles that will reduce fuel consumption by two thirds but otherwise have price, comfort, safety, and other measures of performance similar to the typical automobile now on the market. PNGV vehicle designs are expected to substitute lightweight materials, such as aluminum, magnesium, carbon-reinforced polymer composites, glass-reinforced polymer composites, and ultra- light steel, for heavier materials such as steel and iron in automobile components. The target mass of a PNGV vehicle is 1,960 pounds, as compared to the average current vehicle that weights 3,240 pounds. Other changes could include the use of different ferrous alloys, engineering changes, or incorporation of advanced ceramic components. Widespread adoption of these vehicle designs would affect materials markets and require concurrent development and adoption of supporting technologies to supply the ...
1997-08-01
International Nuclear Information System (INIS)
This report summarizes the findings of a five-month LDRD project funded through Sandia's NTM Investment Area. The project was aimed at providing the foundation for the development of advanced functional materials through the application of ultrathin coatings of microporous or mesoporous materials onto the surface of substrates such as silicon wafers. Prior art teaches that layers of microporous materials such as zeolites may be applied as, e.g., sensor platforms or gas separation membranes. These layers, however, are typically several microns to several hundred microns thick. For many potential applications, vast improvements in the response of a device could be realized if the thickness of the porous layer were reduced to tens of nanometers. However, a basic understanding of how to synthesize or fabricate such ultra-thin layers is lacking. This report describes traditional and novel approaches to the growth of layers of microporous materials on silicon wafers. The ...
Energy Technology Data Exchange (ETDEWEB)
This paper describes high speed rolling and gauge control in cold tandem mill for ultra-thin gauge strip at the Chiba Works of Kawasaki Steel Corporation. To improve the plate-out property of rolling oil, cationic polymeric coagulant was prepared. Rolling oil with cohesion independent of inorganic inclusions or phosphatide was developed, to improve the lubrication for cold rolling, remarkably. In addition, a low-cost Ti-enhanced work roll having high wear resistance and excellent grindability was developed. Rolling can be conducted at the optimal rolling roughness and operation can be performed at the highest rolling speed independent of the rolling treatment amount. Rolling speed at 2800 m/min was confirmed by developing the rolling oil with excellent lubrication and the work roll having high wear resistance. For the improvement of strip thickness accuracy at the steady state rolling, use of the backup roll as roller bearing was more effective rather than the ...
1996-09-01
Point defect engineering in preamorphized silicon enriched with fluorine
International Nuclear Information System (INIS)
Fluorine is known to have a beneficial role for the B diffusion reduction in preamorphized Si, and is promising for the realization of ultra-shallow junctions. Thus, we studied the F incorporation in Si during the solid phase epitaxy (SPE) process, pointing out the effects of the implanted F energy and fluence and the role played by the possible presence of dopants. The incorporation of fluorine proceeds by F segregation at the amorphous-crystalline interface, with a kinetics driven by the SPE rate. In fact, the quicker the SPE rate, the higher is the F fluence retained. Moreover, we demonstrated that F incorporated in Si layers does not appreciably affect the Is emission from spatially separated end-of-range (EOR) defects. The modification, induced by the presence of F, of the point defect density (Is and Vs) was also studied by means of B and Sb spike layers, used as local markers for Is and Vs, respectively. We showed that F is not only able to completely ...
2006-12-01
Oxygen stabilization induced enhancement in superconducting characteristics of high-Tc oxides
International Nuclear Information System (INIS)
In an attempt to enhance the electrical and mechanical properties of the high temperature superconducting oxides, high T(sub c) composites were prepared composed of the 123 compounds and AgO. The presence of extra oxygen due to the decomposition of AgO at high temperature is found to stabilize the superconducting 123 phase. Ag is found to serve as clean flux for grain growth and precipitates as pinning center. Consequently, almost two orders of magnitude enhancement in critical current densities were also observed in these composites. In addition, these composites also show much improvement in workability and shape formation. On the other hand, proper oxygen treatment of Y5Ba6Cu11Oy was found to possibly stabilize superconducting phase with T(sub c) near 250 K. I-V, ac susceptibility, and electrical resistivity measurements indicate the existence of this ultra high T(sub c) phase in this compound. Detailed structure, microstructure, electrical, magnetic and thermal ...
1991-01-01
Modelisation of boron diffusion from ultra-low-energy implantation in crystalline silicon
Energy Technology Data Exchange (ETDEWEB)
We have investigated and modeled the boron diffusion in silicon following ultra-low-energy implantation (500 eV). It is well known that reducing implant energies is an effective way to eliminate transient enhanced diffusion due to the excess of interstitials from the implant. However, for sub-keV B implants diffusion remains enhanced. This enhancement is linked to the presence of a silicon boride layer located at the silicon surface which creates interstitials. This phenomenon is named 'boron enhanced diffusion' (BED). The BED effect is of obvious interest since it counteracts the advantage obtained by reducing the ion implantation energy. For these reasons, we have investigated the diffusion of low-energy boron implanted in crystalline silicon and tested a complete simulation program, which takes into account the effect of boron precipitation and the effect of the silicon boride layer as a source of self-interstitials. Experimental results have ...
2003-12-31
Energy Technology Data Exchange (ETDEWEB)
Supermetal with critical characteristics is under advanced investigation for further improvement of metal materials. Although iron is most frequently used as structural material among various metals, it should be used more carefully and effectively because of resource limitation and global environmental problem. It is essential to draw various excellent properties much more from iron and to improve recyclability. In particular, the best way to meet these requirements is achievement of more fine structure and higher purity. Since the lowest crystalline grain size is now limited to nearly 10{mu}m, metallic structure composed of grains below 1{mu}m is expected by mesoscopic control. Various methods have been studied to achieve ultra-fine crystalline structure, and study of precise heat treatment control and ultra-strength metallurgy is required. Heat treatment in magnetic field and layered structure by mechanical alloying are also promising. ...
1996-03-01
Gamma-ray burst (GRB) is one of the candidates of high-energy cosmic-ray acceleration sites. They may be also ultra-high-energy (above 3 EeV) cosmic-ray (UHECR) sources. In this paper, we discuss possibilities and implications of high-energy cosmic-ray acceleration in GRBs. (1) First, we show that not only protons but also heavier nuclei can be accelerated up to ultra-high energies in both usual high-luminosity (HL) and low-luminosity (LL) GRBs by using the Geant4. LL GRBs may also make a significant contribution to the observed UHECR flux if they form a distinct population, and we investigate cosmic-ray acceleration in LL GRBs in detail. (2) Second, we discuss implications of the GRB-UHECR hypothesis (and Hypernova-UHECR hypothesis) to cosmic-ray astronomy. HL GRBs and LL GRBs will lead to different source number densities as UHECR sources, so that the determination of the number density of UHECR sources and strength of the mean extragalactic ...
2008-01-01
High Angular Resolution Imaging Spectroscopy of the Galactic Ultra-Compact HII Region K3-50A
Gemini North adaptive optics imaging spectroscopy is presented for the Galactic ultra-compact HII (UCHII) region K3-50A. Data were obtained in the K-band using the Near-infrared Integral Field Spectrograph (NIFS) behind the facility adaptive optics module ALTAIR in natural guide star mode. The NIFS data cube reveals a complex spatial morphology across the 0.1 pc scale of the 3'' UCHII region. Comparison of the nebular emission to Cloudy ionization models shows that the central source must have an effective temperature between about 37000 K and 45000 K with preferred values near 40000 K. Evidence is presented for sharp density variations in the nebula which are interpreted as a clearing of material nearest the central source. High excitation lines of FeIII and SeIV show that the ionization of the nebula clearly changes with distance from the central source. A double lobed kinematic signature (+/- 25 kms) is evident in the Br gamma line map which may be related to ...
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
A 19.1 metre wind turbine blade was subjected to static tests. The purpose of the test series was to verify the abilities of different types of sensors to detect damage in wind turbine blades. Prior to each of the static test-series an artificial damage was made on the blade. The damage made for each test-series was surveyed during each series by acoustic emission, fiber optic micro bend displacement transducers and strain gauges. The propagation of the damage was determined by use of ultra sonic and X-ray surveillance during stops in the test series. By use of acoustic emission it was possible to measure damage propagation before the propagation was of visible size. By use of fiber optic micro bend displacement transducers and strain gauges it was possible to measure minor damage propagation. By use of both ultra sonic, and X-ray NDT-equipment it were possible to determine the size of propagated damage. (au)
2002-05-01
Energy Technology Data Exchange (ETDEWEB)
Experimental discussions were given on effect of V and W addition on the high temperature strength properties of 12% Cr-15% Mn austenite steels. The test samples were added with W at 0% to 3.5% and V at 0% to 0.5% in addition to C and N, and were given aging treatment or solution treatment. This paper describes the following matters on the results of high-temperature strength measurements and structural observation: A remarkable trend was observed that M23 Cb type carbides precipitate in the aging treatment, wherein aging hardening appears prominently which is attributable to ultra-fine deposits of vanadium nitride (VN) in the V-added material; the V addition is very effective in increasing the high-temperature tensile strength and creep fracture strength as compared with single W addition, wherein the said carbides that accelerate the precipitation as a result of the V addition make a large contribution, in addition to that by ultra-fine VN ...
1992-11-01
Energy Technology Data Exchange (ETDEWEB)
In the development of the specific mathematical modeling for heavy and ultra heavy petroleum fractions in a molecular distiller is very important the definition of physical and chemical parameters as density and specific heat of the mixture, the enthalpy of vaporization, among others, since they are used in the energy balance. Information on these properties and their variation with temperature are found in the open literature for mixture with few components (simple mixtures). However, for multicomponent solutions consisting of complex mixtures such as oil and its heavy and ultraheavy fractions, available data are few, or are limited to low temperatures. The specific heat is an important property in the energy balance. This property can be measured by Differential Scanning Calorimetry (DSC), which gives results with great sensitivity and accuracy. This paper presents the variation of specific heat with the temperature of ultra-heavy oil ...
2008-07-01
Coherent Electromagnetic Processes in Ultra-Peripheral Heavy-Ion Collisions
We report measurements for coherent rho^0 production, AuAu->AuAu rho^0, and coherent rho^0 and e^+e^- pair production accompanied by mutual nuclear Coulomb excitation, AuAu->Au*Au* rho^0 and AuAuee, in ultra-peripheral relativistic gold-gold collisions (UPC). We discuss transverse momentum, mass, and rapidity distributions. The two photon-process of e^+e^- pair production is an important probe of strong field QED because of the large coupling Z*alpha=0.6. At sqrt{s}=200GeV, the e^+e^- production cross section agrees with lowest order QED calculations. The cross sections for coherent rho^0 production at sqrt{s}=130 and 200GeV are in agreement with theoretical predictions. The calculations for both, coherent e^+e^- and rho^0 production treat nuclear excitation as independent process.
2004-01-01
A new application of MRT of the lung using ultra-shot turbo spin echo sequences (UTSE)
International Nuclear Information System (INIS)
T_2 weighted ultra-short turbo spin echo sequences were used in five individuals with variations in echo times, delayed triggering and echo intervals. To reduce movement artifacts all examinations were carried out with ECG and respiratory triggering. The sequences giving optimal image quality were then employed in 19 patients having various pulmonary abnormalities. Image resolutions, artifacts, image contrasts and diagnostic value were then judged by two observers and compared with CT. In the first study, a diastole-triggered UTSE sequence with the shortest echo proved optimal (T_E=90 ms, T_R=2-4 s, echo=9 ms, turbo factor=19). In the patient series studied, MRT was inferior to CT with regard to resolution and number of artifacts, but better in respect of contrast and diagnostic value. Using UTSE of the lung, MRT can produce images of good quality. Compared with CT, contrast is better with MRT, offering diagnostic advantages for MRT. (orig./MG).
Energy Technology Data Exchange (ETDEWEB)
The main driver in ultra-shallow formation for the 65 nm technology node and beyond is to find solutions that both reduce boron transient enhanced diffusion and can be integrated in the CMOS process flow. To this end, many studies have recently focused on using co-doping techniques with fluorine and most recently with carbon. In most cases, one or both of these is co-implanted with a dopant specie in pre-amorphized silicon. In this work, we show a comparative study of fluorine or carbon co-implanted with low-energy boron to form source and drain extension junctions for PMOS devices. We will show that by a systematic optimization of germanium, boron, fluorine or carbon energies and doses, spike annealing technology can be extended to the 65 nm node. These results will be used to discuss how the different formed junctions offer potential solutions for either low-power or high-performance PMOS device fabrication.
2005-12-05
"Mtrack 2.0": An ultra-scale tracking algorithm for low-resolution overhead imagery
Energy Technology Data Exchange (ETDEWEB)
Overhead persistent surveillance systems are becoming more capable at acquiring wide-field image sequences for long time-spans. The need to exploit this data is becoming ever greater. The ability to track a single vehicle of interest or to track all the observable vehicles, which may number in the thousands, over large, cluttered regions while they persist in the imagery is very desirable. Typically, this imagery has many thousands of pixels on a side and is characterized by lower resolutions (e.g. {approx}0.5 meters/pixel to {approx}2.0 meters/pixel) and lower frame rates (e.g. {approx} sub-Hz to several Hz). We describe our ultra-scale capable implementation of a multiple-vehicle tracking algorithm for overhead persistent surveillance imagery. This work builds upon an earlier report, where now the algorithm has been modified for improved performance and has been substantially improved to handle much larger datasets in a much shorter time.
2008-09-26
The development of Soviet rocket engines (For strategic missiles)
Energy Technology Data Exchange (ETDEWEB)
A first-hand account of developments in the Soviet rocket industry is presented. The organization and leadership of the rocket and missile industry are traced from its beginning in the 1920s. The development of the Glushko Experimental Design Bureau, where the majority of Soviet rocket engines were created, is related. The evolution of Soviet rocket engines is traced in regard to both their technical improvement and their application in missiles and space vehicles. Improved Glushko engines and specialized Isaev and Kosberg engines are discussed. The difficulties faced by the Soviet missile and space program, such as the pre-Sputnik failures, the oscillation problem of 1965/1966, which exposed a weakness in Soviet ICBM missiles, and the Nedelin disaster of 1960, which cost the lives of more than 200 scientists and engineers, as well as the Commander-in-Chief of the Strategic Rocket Forces, Marshall Nedelin, are examined. 122 refs.
1991-01-01
British Library Electronic Table of Contents (United Kingdom)
Taking the port city of Alicante the author outlines how numerous crossroads connect the northern and southern shores of the Mediterranean. Along the arc of Euro-Mediterranean trading centres lies the European continent as a whole, extending eastwards to the republics emerging from the disintegration of the Soviet Empire, and in the south to Francophone and Muslim Africa. This arc of trading towns includes Istanbul, Dubai, Naples, Antwerp, Hamburg, Marseilles and Alicante. The author traces the movements of individuals pursuing "suitcase trade" performed by means of face-to-face links, word of mouth, and verbal agreements. The author then traces this vast "choreographed movement" that originates from Europe's borders, and suggests that although reasons other than trade influence mobility a...
2007-01-01
British Library Electronic Table of Contents (United Kingdom)
In this paper we provide a geochemical investigation on 34 groundwater samples in the Mt. Vulture volcanic aquifer representing one of the most important groundwater resources of the southern Italy pumped for drinking and irrigation supply. The present study includes the first data on the abundance and mobility of minor and trace elements and the thermodynamic considerations on water-rock interaction processes in order to evaluate the conditions of alkali basalt weathering by waters enriched in magma-derived CO2. The results highlight the occurrence of two hydrofacies: bicarbonate alkaline-earth and alkaline waters deriving from low-temperature leaching of volcanic rocks of Mt. Vulture, and bicarbonate-sulfate-alkaline waters (high-salinity waters) related to prolonged water circulation in...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
One hypothesis for the decline of the North American greater (Aythya marila) and lesser (A. affinis) scaup population is that contaminant burdens acquired on wintering or staging areas impair reproduction or cause lethal or sublethal health effects. Recent studies have found increased selenium (Se) concentrations in scaup but have focused on the fall and spring staging periods. From January to March 2006 and December to March 2006 and 2007, we analyzed liver tissues collected from greater scaup wintering in western Lake Ontario for 16 trace elements. We also measured Se concentrations in greater scaup blood and Dreissenid mussel tissue. Se was the only trace element that occurred at increased concentrations (>10??g/g liver dry weight) in a substantial proportion (99%) of greater scaup live...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
We collected female greater scaup (Aythya marila) on the Yukon-Kuskokwim Delta, Alaska during two breeding seasons to determine if concentrations of 18 trace elements in livers and eggs were elevated and if hepatic concentrations correlated with body condition or affected reproductive status. Fifty-six percent, 5%, and 42% of females, respectively, had elevated hepatic cadmium (Cd: >3mgg-1 dry weight [dw]), mercury (Hg: >3mgg-1dw), and selenium (Se: >10mgg-1dw). Somatic protein and lipid reserves were not correlated with hepatic Cd or Hg, but there was a weak negative correlation between protein and Se. Hepatic Cd, Hg, and Se were similar in females that had and had not initiated egg production. In a sample of six eggs, 33% and 100%, respectively, contained Se and Hg, but concentrations we...
2009-01-01
Regulation of natural gas: policy and politics, 1938-1978
Energy Technology Data Exchange (ETDEWEB)
The history of the political process surrounding regulations is traced from the 1930s, when the natural gas industry and the Federal Power Commission were in their infancy. The author traces the changing mandate that Congress has provided the regulators and the instincts for self-preservation that these bureaucrats have manifested when they suspected a change in presidential administration or a new decision from the Supreme Court. Natural gas has been one political issue that has split Congress by region. The economic interests of producer and consumer states have often been at such odds that regulation has involved the question of redistribution of wealth among regions as well as between households and industry. The picture is complicated by the link between gas production and distribution and the production and distribution of coal and oil. 12 figures, 25 tables.
1981-01-01
Microwave transport in EBT distribution manifolds using Monte Carlo ray-tracing techniques
Energy Technology Data Exchange (ETDEWEB)
Ray tracing Monte Carlo calculations have been carried out using an existing Monte Carlo radiation transport code to obtain estimates of the microsave power exiting the torus coupling links in EPT microwave manifolds. The microwave power loss and polarization at surface reflections were accounted for by treating the microwaves as plane waves reflecting off plane surfaces. Agreement on the order of 10% was obtained between the measured and calculated output power distribution for an existing EBT-S toroidal manifold. A cost effective iterative procedure utilizing the Monte Carlo history data was implemented to predict design changes which could produce increased manifold efficiency and improved output power uniformity.
1983-01-01
International Nuclear Information System (INIS)
Using the Laser-Fluorescence technique, an investigation was made, adopting the standard mix method, on trace uranium concentrations in hot spring water and geothermal water from Lishan region, and in tap water from some major cities in Shanxi province. Totally 40 samples from 27 sites were investigated. Measurement showed that the tap water contains around 10"-"6 g/L of uranium, whose concentrations in both hot spring water and geothermal water are 10"-"5 g/L. Most of samples are at normal radioactive background level, some higher contents were determined in a few samples
2002-03-01
International Nuclear Information System (INIS)
Lead is contained as trace element in uranium ores and propagates throughout the production process to intermediate products like yellow cake or uranium oxide. The lead isotopes in such material originate from two sources: natural lead and radiogenic lead. The variability of the isotopic composition of lead in ores and yellow cakes was studied and the applicability of this parameter for nuclear forensic investigations was investigated. Furthermore, the chemical impurities contained in these materials were measured in order to identify characteristic differences between materials from different mines. For the samples investigated, it could be shown, that the lead isotopic composition varies largely from mine to mine and it may be used as one of the parameters to distinguish between materials of different origins. Some of the chemical impurities show a similar pattern and support the conclusions drawn from the lead isotope data. (orig.)
British Library Electronic Table of Contents (United Kingdom)
Abstract The Jebel Ressas Pb-Zn deposits in North-Eastern Tunisia occur mainly as open-space fillings (lodes, tectonic breccia cements) in bioclastic limestones of the Upper Jurassic Ressas Formation and along the contact of this formation with Triassic rocks. The galena-sphalerite association and their alteration products (cerussite, hemimorphite, hydrozincite) are set within a calcite gangue. The Triassic rocks exhibit enrichments in trace metals, namely Pb, Co and Cd enrichment in clays and Pb, Zn, Cd, Co and Cr enrichment in carbonates, suggesting that the Triassic rocks have interacted with the ore-bearing fluids associated with the Jebel Ressas Pb-Zn deposits. The 18O content of calcite associated with the Pb-Zn mineralization suggests that it is likely to have precipitated from a fl...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
A compact and supersensitive device that can rapidly detect minute trace vapors from concealed explosives has been developed by scientists at Oak Ridge National Laboratory (ORNL). The new explosives sensor can detect and chemically identify organic nitrogen-oxygen compounds which are the building blocks of explosives such as TNT, plastiques, and nitroglycerine. The device could be used to scan persons entering airport terminals, nuclear power plants, defense installations, or other sensitive locations, providing greater security against potential terrorism. This device works on a glow discharge principle, and is more specifically called an ''Atmospheric Sampling Glow Discharge Ionization'' (ASGDI) source. The new detector is a highly automated, miniaturized version of research mass spectrometers widely used to trace constituents of chemical mixtures. Detail of this device's construction and ...
1987-01-01
Estimating the erosion and deposition rates in a small watershed by the 137Cs tracing method
International Nuclear Information System (INIS)
Understanding the erosion and deposition rates in a small watershed is important for designing soil and water conservation measures. The objective of this study is to estimate the net soil loss and gain at points with various land use types and landform positions in a small watershed in the Sichuan Hilly Basin of China by the 137Cs tracing technique. Among various land use types, the order of erosion rate was bare rock > sloping cultivated land > forest land. The paddy field and Caotu (a kind of cultivated land located at the foot of hills) were depositional areas. The erosion rate under different landform was in this order: hillside > saddle > hilltop. The footslope and the valley were depositional areas. The 137Cs technique was shown to provide an effective means of documenting the spatial distribution of soil erosion and deposition within the small watershed.
2009-02-01
Contaminants in Lesser and Greater Scaup Staging on the Lower Great Lakes
British Library Electronic Table of Contents (United Kingdom)
The decrease and subsequent lack of recovery of the North American scaup population has increased concerns about contaminants acquired during migration. We collected 189 fall- and spring-migrant lesser (Aythya affinis) and greater scaup (A. marila) on the lower Great Lakes (LGL) to determine if organic contaminants and trace elements in scaup livers were increased and to evaluate sources of variation in selenium (Se) burdens. We found that all organic contaminants were below toxic levels. Of 18 trace elements, only Se was detected at increased (>10-ppm dry-mass) levels. Se in lesser scaup increased but remained constant in greater scaup throughout fall; levels were increased in 14% of lesser scaup and 46% of greater scaup. During spring, Se increased in lesser scaup but decreased slightly ...
2007-01-01
Comparison of methods used for preparation of biological CRM`s
Energy Technology Data Exchange (ETDEWEB)
The starting material for two certified and one candidate reference material was obtained from dried grass specially cultivated on a selected and well prepared soil. The Community Bureau of Reference (BCR) of the Commission of the European Communities produced two certified reference materials (CRM`s) from this dried grass: a rye grass material (CRM 281) certified in 1988 for the quality control of trace and toxic element analyses and a hay powder material (CRM 129) certified in 1989 for monitoring trace and minor elements. A fraction of the dried grass was used in 1993 for the preparation of a hay powder with a particle size of < 63 {mu}m using newly developed grinding techniques. This paper compares the production methods of these three materials and the obtained particle size distribution of the powders. The analytical evaluation of these production methods was carried out by solid sampling Zeeman atomic absorption spectrometry for the ...
1995-05-01
International Nuclear Information System (INIS)
In this work, a water-soluble polymer, polyethylenimine (PEI) was used for the simultaneous separation and preconcentration of trace Cu and Mn prior to their determination by flame atomic absorption spectrometry. For this purpose, the sample and the PEI solution were mixed and the metal-bound polymer was precipitated by adding acetone. The precipitate was separated and dissolved in a minimum amounts of water and aspirated into a flame AAS. By increasing the ratio of the volumes of sample to water used in dissolving the precipitate, the analyte elements were concentrated as needed. The sorption is quantitative in the pH ?6. Detection limits were 5.2 ?g/L for Cu and 5.4 ?g/L for Mn. This method is simple, fast and precise.
2006-04-21
A rheological assessment of the effect of trace level Ni additions on the solidification of Sn?0.7Cu
British Library Electronic Table of Contents (United Kingdom)
The influence of trace level Ni additions on the eutectic solidification mode of Sn?0.7Cu has been studied using continuous torque experiments during solidification. The solid fraction at which resistance to paddle rotation at the thermal centre of the sample occurs is related to the spatial distribution of solid during solidification. The results indicate that a transition in solidification mode occurs in the range 0?300ppm Ni. Growth occurs antiparallel to heat flow from near the mould walls in the Ni-free alloy, while equiaxed growth from distributed centres dominates in alloys containing at least 300ppm Ni.
2006-01-01
{sup 242m}Am fueled nuclear battery
Energy Technology Data Exchange (ETDEWEB)
A nuclear battery based on the direct energy conversion of the fission products is presented. Such energy conversion is possible by using a nuclear reactor with ultra-thin fuel elements of 0.2 {mu}m of {sup 242m}Am. The amount of nuclear fuel is 376 g and the dimensions of the battery are 2.4x2.4x2.4 m{sup 3} (including the vacuum spacing), with a BeO moderator and Be electrodes. The total power of the reactor is 10.6 MW and the electrical power is 0.652 MW.
2004-10-01
Ultra-thin {sup 242m}Am fuel elements in nuclear reactors. II
Energy Technology Data Exchange (ETDEWEB)
There is growing interest in using {sup 242m}Am as a nuclear fuel for space reactors and nuclear batteries. In this paper, we discuss different {sup 242m}Am enrichments, as well as fuel weight requirements, to produce a critical reactor. It was found that relatively low enrichments of {sup 242m}Am, about 10 w/o, are enough to guarantee criticality. Such low enrichments might eliminate the need for a {sup 242m}Am enrichment process. It was also found that the best results for low {sup 242m}Am requirements are obtained with a moderator to fuel volume ratio of 10,000.
2004-04-21
Star Formation in the Outer Disks of Spiral Galaxies
This is a study done in collaboration with Deidre Hunter at Lowell Observatory studying star formation in two luminous spiral galaxies NGC 801 and UGC 2885. We used ultra-deep H? images taken at the KPNO 2.1 m telescope. We compare these data to stellar images at various wavelengths and to HI maps to determine the extent of star formation activity into the outer disk in these galaxies and its relationship to the gas and older stars. TW is grateful for an REU internship during the summer of 2010 at Northern Arizona University, funded by NSF through grant AST-1004107.
2011-01-01
International Nuclear Information System (INIS)
Energy deposition process by relativistic fast electrons produced by ultra-intense laser pulses is discussed. The process is calculated with a two dimensional Fokker-Planck simulation code including binary and collective collisions coupled with electromagnetic field. We focused on Velocity Distribution Function (VDF) dependence in the simulation. The results show that the spread angle of the fast electrons distribution affects energy deposition area and deposited energy is concentrated in the vicinity of the propagation axis of the fast electrons. It may be also suggested that self-pinch effect of a fast electron beam causes large deposition energy. (author)
2008-03-01
Problems and approach to geological disposal of radioactive waste
International Nuclear Information System (INIS)
This feature articles described a concept and technical problems of geological disposal of high-level radioactive waste in the civil engineering. It consists of six papers such as the present statues and subjects of geological disposal by KITAYAMA Kazumi, the diastrophism, igneous activity, and upheaval and erosion by YAMAZAKI Haruo, the groundwater flow and evaluation of nuclear transfer by IJIRI Yuji, evaluation of alteration of cement materials in the ultra-long period by HAGA Kazuko, The Mizunami Underground Research Laboratory in course of construction by SAKAMAKI Masanori, and interview of the ninetieth president of JSCE (Japan Society of Civil Engineers), he places his hope on JSCE and civil engineers by KISHI Kiyoshi. (S.Y.)
2006-11-01
Orthophosphoric acid interactions with ultrastable zeolite Y: Infrared and NMR studies
Energy Technology Data Exchange (ETDEWEB)
Zeolite Y is the active component of most commercial cracking catalysts. Interaction of H[sub 3]PO[sub 4] with extraframework aluminum of ultra-stable zeolite (USY) leads to the formation of different types of aluminum phosphates, while there is no indication of the formation of SAPO zeotype structures. The total acidity of USY slightly decreases upon the H[sub 3]PO[sub 4] treatment, while the maximum in the distribution of acid strength is shifted to milder acidities. Dealumination of the zeolite and creation of POH sites associated with AIPO[sub 4] are responsible for the modifications observed. 37 refs., 8 figs., 3 tabs.
1994-01-01
Multilayer ultra high gradient insulator technology
Energy Technology Data Exchange (ETDEWEB)
We are investigating a novel insulator concept which involves the use of alternating layers of conductors and insulators with periods less than 1 mm. These structures perform many times better (about 1.5 to 4 times higher breakdown electric field) than conventional insulators in long pulse, short pulse, and alternating polarity applications. We present our ongoing studies investigating the degradation of the breakdown electric field resulting from surface roughness, the effect of gas pressure, and the performance of the insulator structure under bi-polar stress. Further, we present our initial modeling studies.
1998-03-27
Improved formability of ultra high strength steels through local heat treatment
Energy Technology Data Exchange (ETDEWEB)
In this paper it is described how a martensitic steel sheet with tensile strength of 1400 MPa is heat treated locally. The sheet is then formed in the heat treated regions in a way that would be impossible with the untreated material. Mechanical properties and forming limit diagrams of the heat treated material are determined and the forming operations are simulated, which shows that the method can be used by designers. Although the method has been known for decades, it remains to be industrialised and the work presented here is to be seen as a contribution to this development. (orig.)
2005-07-01
Enhancement of Heat and Mass Transfer in Mechanically Contstrained Ultra Thin Films
Energy Technology Data Exchange (ETDEWEB)
Oregon State University (OSU) and the Pacific Northwest National Laboratory (PNNL) were funded by the U.S. Department of Energy to conduct research focused on resolving the key technical issues that limited the deployment of efficient and extremely compact microtechnology based heat actuated absorption heat pumps and gas absorbers. Success in demonstrating these technologies will reduce the main barriers to the deployment of a technology that can significantly reduce energy consumption in the building, automotive and industrial sectors while providing a technology that can improve our ability to sequester CO{sub 2}. The proposed research cost $939,477. $539,477 of the proposed amount funded research conducted at OSU while the balance ($400,000) was used at PNNL. The project lasted 42 months and started in April 2001. Recent developments at the Pacific Northwest National Laboratory and Oregon State University suggest that the performance of absorption and desorption systems can be ...
2005-01-01
Direct dark matter identification with a hybrid detection technique
In the quest to understand the ultimate nature of WIMPs, we propose the use of a hybrid detection technique: cylinders filled with liquefied noble gasses, acting as targets, are immersed inside a tank of Gd-doped ultra-pure water that provides an active and efficient veto against neutrons. The evaluation of the background rejection capabilities and physics potential of this instrument have been carried out through a full GEANT4 simulation, assuming the detector will be located at the Canfranc underground laboratory (in the Spanish Pyrenees). Our results compare very favourably with existing or planned experiments in the field. This technique is scalable and will allow to reach target masses of few tonnes in the next future.
2008-01-01
Cosmic no hair for collapsing universes
Energy Technology Data Exchange (ETDEWEB)
It is shown that all contracting, spatially homogeneous, orthogonal Bianchi cosmologies that are sourced by an ultra-stiff fluid with an arbitrary and, in general, varying equation of state asymptote to the spatially flat and isotropic universe in the neighbourhood of the big crunch singularity. This result is employed to investigate the asymptotic dynamics of a collapsing Bianchi type IX universe sourced by a scalar field rolling down a steep, negative exponential potential. A toroidally compactified version of M*-theory that leads to such a potential is discussed and it is shown that the isotropic attractor solution for a collapsing Bianchi type IX universe is supersymmetric when interpreted in an 11-dimensional context.
2006-05-21
Ultra high vacuum test setup for electron gun
Energy Technology Data Exchange (ETDEWEB)
Ultra High Vacuum (UHV) test setup for electron gun testing has been developed. The development of next generation light sources and accelerators require development of klystron as a radio frequency power source, and in turn electron gun. This UHV electron gun test setup can be used to test the electron guns ranging from high average current, quasi-continuous wave to high peak current, single pulse etc. An electron gun has been designed, fabricated, assembled and tested for insulation up to 80 kV under the programme to develop high power klystron for future accelerators. Further testing includes the electron emission parameters characterization of the cathode, as it determines the development of a reliable and efficient electron gun with high electron emission current and high life time as well. This needs a clean ultra high vacuum to study these parameters particularly at high emission current. The cathode emission current, work function and ...
2008-05-01
Pressurized electroosmotic dewatering (PED) of fine coal suspensions
Current dewatering methods for ultra-fine coal suspensions are inadequate and usually require subsequent expensive thermal drying. This unique dewatering method is based on pressurized electroosmosis, the movement of water by an electrical field through a porous medium, under modest pressure, e.g., 110 psi. More ultra-fine coal can be utilized since an effective dewatering process can be realized by combining known filtration techniques with electroosmosis. The dewatering efficiency can be significantly improved, the residual moisture of the cake can be substantially reduced and handling problems can be eliminated. Bench-scale testing is being used to optimize the parameters which influence pressurized electroosmotic dewatering (PED) of ultra-fine coal suspensions. Particle size distribution is being addressed to obtain a maximum density for a given pressure such that pore saturation is maintained allowing electroosmosis to ...
1985-01-01
Energy Technology Data Exchange (ETDEWEB)
Our objective was to evaluate the feasibility of ultra-low-dose scanning for multislice CT colonography in the detection of colorectal lesions. Twenty-seven patients (14 men, 13 women) with clinical indication for conventional colonoscopy were recruited. Multislice spiral CT (Somatom Plus 4 Volume Zoom, Siemens, Germany) examinations were performed after standard oral colonoscopic preparation and colonic distension with room air. Images were acquired using 2.5-mm collimation, 3.0-mm slice thickness, standard reconstruction kernel, 140 kVp, and 10 mAs. Supine and prone acquisitions were obtained in all patients. Images were analyzed on a workstation by two gastrointestinal radiologists. Conventional colonoscopy was performed on the same day in all patients and represented the standard of reference. Total radiation exposure was also calculated. All colorectal cancers were correctly identified at CT colonography (9 of 9, sensitivity 100%). The CT colonography also ...
2003-06-01
UK PubMed Central (United Kingdom)
We characterized the absorption and short-term translocation of cadmium (Cd) in rice (Oryza sativa ‘Nipponbare’) quantitatively using serial images observed with a positron-emitting...Full Text Available
2010-04-01
Quantitative spectroscopy of close binary stars
The method of spectral disentangling has now created the opportunity for studying the chemical composition in previously inaccessible components of binary and multiple stars. This in turn makes it possible to trace their chemical evolution, a vital aspect in understanding the evolution of stellar systems. We review different ways to reconstruct individual spectra from eclipsing and non-eclipsing systems, and then concentrate on some recent applications to detached binaries with high-mass and intermediate-mass stars, and Algol-type mass-transfer systems.
2011-01-01
Proof of the closed-universe recollapse conjecture for general Bianchi type-IX cosmologies
Energy Technology Data Exchange (ETDEWEB)
It is proven that there do not exist any Bianchi type-IX universes which expand for an infinite time, provided only that the matter satisfies the dominant energy condition and has non-negative average pressure (i.e., a non-negative trace of the spatial projection of the stress-energy tensor). This generalizes a proof recently given by us for the case of diagonal Bianchi type-IX solutions.
1990-04-15
Proof of the closed-universe recollapse conjecture for general Bianchi type-IX cosmologies
International Nuclear Information System (INIS)
It is proven that there do not exist any Bianchi type-IX universes which expand for an infinite time, provided only that the matter satisfies the dominant energy condition and has non-negative average pressure (i.e., a non-negative trace of the spatial projection of the stress-energy tensor). This generalizes a proof recently given by us for the case of diagonal Bianchi type-IX solutions.
Progress of magnetic-suspension systems and magnetic bearings in the USSR
International Nuclear Information System (INIS)
This paper traces the development and progress of magnetic suspension systems and magnetic bearings in the USSR. The paper describes magnetic bearings for turbomachines, magnetic suspension systems for vibration isolation, some special measuring devices, wind tunnels, and other applications. The design, principles of operation, and dynamic characteristics of the system are presented.
1992-05-01
Particle acceleration by stimulated emission of radiation near a solid-state active medium
British Library Electronic Table of Contents (United Kingdom)
We report acceleration of electrons moving in free space near an active Nd:YAG slab. The power of a non-relativistic beam of electrons has increased by more than 30% when the medium was excited. It is demonstrated experimentally that the energy gained by the electrons is linearly proportional to the energy stored in the medium. Moreover, the energy gain traces closely the population inversion inferred by monitoring the spontaneous radiation.
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The Formerly Utilized Sites Remedial Action Program (FUSRAP) is to evaluate the radiological conditions at former MED-US AEC sites. Purpose of the Ocean FUSRAP program is to assess the feasibility of ocean disposal of FUSRAP waste which contains trace natural radioactive materials. This paper presents soil characterization information on the Middlesex, NJ, Sampling Plant site, and reports preliminary ocean dispersion calculations. (DLC)
1982-01-01
Mathematical two-dimensional model for three-phase filtering of compressible fluids
Energy Technology Data Exchange (ETDEWEB)
A mathematical model is proposed for three-phase filtering which is a particular case of a more general model of filtering multiple component mixtures and makes it possible to describe three-phase filtering flows under conditions where the pressure of saturation is variable in time and in space. In the proposed model, the system of unknown functions is selected so that it makes it possible to trace fairly simply the pressure of saturation and to compute the corresponding equation coefficients.
1982-01-01
International Nuclear Information System (INIS)
Hydrology and hydrogeochemical are auxiliary techniques to valid conceptual hydrogeology an recharge models. Stable isotopes from water trace sources and path flow and Tritium indicates age. This paper is about the use of D 18, D2H y 3H to study the aquifer system on Bajo Cauca antioqueno.
First-break refraction event picking and seismic data trace editing using neural networks
Energy Technology Data Exchange (ETDEWEB)
Interactive seismic processing systems for editing noisy seismic traces and picking the first-break refraction events have been developed using a neural network learning algorithm. The authors employ a back propagation neural network (BNN) paradigm modified to improve the convergence rate of the BNN. The BNN is interactively trained'' to edit seismic data or pick first breaks by a human processor who judiciously selects and presents to the network examples of trace edits or refraction picks. The network then iteratively adjusts a set of internal weights until it can accurately duplicate the examples provided by the user. After the training session is completed, the BNN system an then process new data sets in a manner that mimics the human processor. Synthetic modeling studies indicated that the BNN uses many of the same subjective criteria that humans employ in editing and picking seismic data sets. Automated ...
1993-01-01
Development of 2-D velocity structure model input tool
Energy Technology Data Exchange (ETDEWEB)
The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. Since the FEM (Finite Element Method) ray tracing we have developed goes well the inverse velocities structure, we can apply the inversion problem to complex ...
1996-12-01
UK PubMed Central (United Kingdom)
Seventy male Wistar rats were the recipients of labeled small lymphocytes (1.5 X 10(7) each) collected from the peripheral blood of syngeneic donors. The migrating labeled lymphocytes were traced in...Full Text Available
1978-12-01
Cation exchange separation of trace amounts of {sup 203}Hg and {sup 181}Hf
Energy Technology Data Exchange (ETDEWEB)
A radiochemical method of separation of {sup 203}Hg from {sup 181}Hf is described. The method involves separation by Dowex 50W- X 8, 100-200 mesh, cation exchange resin using 1 M hydrochloric acid as the eluant. The chemical yield for the separation of mercury is > 85% and the decontamination factor is >10{sup 4}. The {sup 181}Hf can be eluted from the column by 4 M HCl.
2000-02-01
International Nuclear Information System (INIS)
In the report the results of the estimations of radiological risk of various stages of decommissioning of nuclear submarines are presented. At occurrence on nuclear submarine the heavy failure, relating to the class hypotetical volume of acting of radionuclides in atmosphere can reach 1.6E(15) Bq. Results of estimations probable doses on an axis of a trace of a radioactive loop show, that at distribution of radionuclides during atmospheric carry to 'agreed' settlement (500-1000 m) the maximum doses on its territory can make: about 6.0E(-3) Sv (for the whole body); 3.0E(-3) Gy for the leather (basal layer); 6.3E(-2) Gy for the lungs (acute exposure) and up to 1.8 Gy for the thyroid gland. Hypotetical failure for the estimation of the greatest possible radioecological consequences for hydrobiocenosis is considering, connected with single discharge of liquid radioactive waste (LRW) in water area. At navigating failure of the tanker with LRW in water area can arrive ...
2000-05-01
Wastewater treatment; Abwasserreinigung
Energy Technology Data Exchange (ETDEWEB)
The methods introduced for the field of cleaning waste water can be classified under various processes. Chemical oxidation is done with ozone, hydrogen peroxide and ultraviolet irradiation with subsequent biological decomposition. Another method is ultra-filtration with recovery of valuable materials or waste water ponds with algae biomass to decompose ammonium compounds, nitrates and phosphates. (EF) [Deutsch] Die auf dem Gebiet der Abwasserreinigung vorgestellten Methoden kann man in verschiedene Verfahren einordnen. Die chemische Oxidation erfolgt mit Ozon, Wasserstoff-Peroxid, UV Bestrahlung und anschliessenden biologischen Abbau. Eine andere Methode ist die Ultrafiltration mit Rueckgewinnung von Wertstoffen oder Abwasserteiche mit Algenbiomasse zum Abbau von Ammoniumverbindungen, Nitraten und Phosphaten. (EF)
1994-11-01
Energy Technology Data Exchange (ETDEWEB)
The formation, migration and agglomeration in silicon of fluorine-vacancy complexes have been monitored by single-detector Doppler broadening spectroscopy. After electronics engineers found that fluorine ion implantation effectively eliminated the transient-enhanced diffusion of dopants in the creation of ultra-shallow junctions, a vital step in the further miniaturization of device structures, positron beams have played a pivotal role in providing an insight into the mechanisms underlying this phenomenon, being able to detect FV complexes in implanted and annealed samples. Secondary Ion Mass Spectrometry has provided complementary information on fluorine concentrations so that the nature of the F{sub m}V{sub n} complexes can be further assessed. New results on Si and SiGe structures are presented.
2008-10-31
Untersuchungen zur Anwendung von UHPFRC-Tubbingen bei der zweischaligen Tunnelbauweise
British Library Electronic Table of Contents (United Kingdom)
Faserbewehrter Beton wird heute zunehmend auch bei Tunnelbauwerken (Tunnelinnenschalen, Tubbinge) eingesetzt. Wesentliche Vorteile sind das hohe Tragvermogen, das daraus entstehende Einsparungspotential an herkommlicher stabformiger Bewehrung (Biegebewehrung, Bugelbewehrung in der Randzone), die Aufnahme von Spaltzugbeanspruchungen durch die Fasern, Rissbreitenbegrenzung, erhohte Dauerhaftigkeit, verbesserter Brandwiderstand (insbesondere bei Verwendung von Kunststofffasern), Optimierung der Arbeitsablaufe etc. Neue Entwicklungen in der Betontechnologie haben in den letzten Jahrzehnten den faserbewehrten ultrahochfesten Beton (engl. UHPFRC - Ultra High Performance Fibre Reinforced Concrete) hervorgebracht. Im Rahmen dieser Arbeit wird der Einsatz des ultrahochfesten, stahlfaserbewehrten Be...
2010-01-01
Ultra high strength beta titanium alloy for fasteners
International Nuclear Information System (INIS)
A new high strength titanium alloy has been developed primarily intended for fastener applications. While Ti-6Al-4V is used extensively as a fastener alloy in the aerospace industry, its shear strength allowable is limited to 655 MPa (95 ksi). For higher shear strength requirements, various steels or nickel-based alloys are used (up to 860 MPa (125 ksi)), but with the attendant density penalty. This new alloy is intended to provide the 860 MPa shear strength at roughly a 40% weight savings. After screening various alloy systems, the optimum chemistry has been selected as follows: Ti-6.0V-6.2Mo-5.7Fe-3Al. In light of its 125 ksi shear strength goal, the alloy has been designated TIMETAL reg-sign 125.
1993-02-21
The investigations on K and L X-ray fluorescence parameters of gold compounds
British Library Electronic Table of Contents (United Kingdom)
The study aimed to determine the chemical effects on the K and L X-ray intensity ratios and the K and L X-ray production cross sections for gold compounds. The K shell fluorescence yields and L shell average yields were also investigated. The samples were excited by 59.5keV ?-rays from an 241Am annular radioactive source and 123.6keV ?-rays from a 57Co annular radioactive source. K and L X-rays emitted from samples were counted by an Ultra-LEGe detector with a resolution of 0.150keV at 5.9keV. The experimental values were compared with theoretical, the semi-empirical and other experimental values.
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
The conductive ultra thin films were fabricated from mixed monolayers containing stearic acid and Head-to-Tail poly(3-alkylthiophene). These films exhibited well-defined layered structures as determined by optical absorption and X-ray diffraction measurements. The UV-Vis absorption spectra of these films showed lower energy absorption shifts of 48 nm from that of the random poly(3-alkylthiophene)/stearic acid LB films. The blue shift of absorption maximum of the LB film is attributed to the increase of {pi}-conjugation length caused by no steric hindrance of alkyl side chains. The conductivity of the Head-to-Tail poly(3-hexylthiophene)/stearic acid LB films was greatly improved in the range of 67-100 S/cm. (orig.)
1997-01-01
Pulsed laser deposition of titanium-carbonitride thin films
Energy Technology Data Exchange (ETDEWEB)
The goal of this research program is to determine whether pulsed laser deposition is an effective alternative method for growing TiCN thin films. Pulsed laser deposition (PLD) is chosen because of its well-documented capability for growing uniform, stoichiometric films in ultra-high vacuum or gaseous environments. Processing of thin films by PLD is also achieved at relatively low temperatures compared with CVD processing. Given these attributes, the primary objectives in this article are to determine whether nitrogen may be readily incorporated into films resulting from the laser-ablation of TiC in an N{sub 2} environment, determine what effect nitrogen has on mechanical properties, and determine whether nitrogen incorporation is strongly influenced by processes unrelated to laser deposition (e.g., thermally-activated surface reactions).
1997-05-15
Potential of AMS for Quantifying Long-Lived Reaction Products
International Nuclear Information System (INIS)
Accelerator mass spectrometry (AMS) represents a powerful technique for the detection of long-lived radionuclides through ultra-low isotope ratio measurements. In many cases, counting atoms rather than decays yields much higher sensitivities. The potential of AMS will be demonstrated on typical radionuclides of interest with half-lives between some tens of years up to a hundred million years. The precise measurement of the 27Al(n,2n)26Al excitation function will be exemplified. Lack of information exists for a list of nuclides as pointed out by nuclear data requests. A brief overview on detection limits and some applications for selected long-lived radionuclides is given.
2005-05-24
British Library Electronic Table of Contents (United Kingdom)
After irradiation at 254nm of aqueous solutions of the antipsychotic drug flupentixol, the structures of the photodegradation products were determined by ultra high performance liquid-chromatography linked to mass spectrometry. Fragmentation patterns of the parent ions were established on a hybrid linear ion trap-orbitrap mass spectrometer allowing accurate mass measurements of both parent and daughter ions. This allowed to propose plausible structures for the main photolysis products of flupentixol. A total of nine photoproducts were detected after irradiation of the drug. The main photoproduct is generated following the addition of a hydroxyl group on the double bond adjacent to the thioxanthene ring. Secondary photoproducts were also observed.
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
A dense Pd-Ag membrane reactor (MR) with 100% hydrogen selectivity packed with either Rh/La2O3 or Rh/La2O3-SiO2 as catalysts was used to carry out the dry reforming of methane. The membrane reactor simulation was performed using a well-known reactor model. For this purpose, we employed the equations derived from complete kinetic studies of the dry reforming of methane reaction in connection with both catalysts. In addition, we developed the kinetic equation for the reverse water gas shift reaction (RWGS). The combination of detailed kinetic studies with the measured permeation flux for the Pd-Ag membrane allowed a complete comparison between experimental and simulated operation variables. The variables studied for both catalysts were methane conversion and hydrogen permeation as a function...
2011-01-01
International Nuclear Information System (INIS)
Pre-amorphization of ultrashallow implanted boron in Silicon-on-insulator is optimized to produce an abrupt box-like doping profile with negligible electrical deactivation and significantly reduced transient enhanced diffusion. The effect is achieved by positioning the as-implanted amorphous/crystalline interface close to the buried oxide interface, to minimize interstitials whilst leaving a single-crystal seed to support solid-phase epitaxy. Based on a simple physical model of our results, we estimate that the interface between the Si overlayer and the buried oxide is an efficient interstitial sink with a recombination length of the order of 10nm or less under our experimental conditions. (author)
2008-12-01
International Nuclear Information System (INIS)
The roughness length at air-sea interface during free convection (Z0fc) is mainly related to the convective velocity (w) rather than the friction velocity (u). The parameterization of Z0fc with (w)2/g as proposed by Abdella and D'Alessio (2003) is evaluated. It is shown that the field measurements at MM Lab, Tarapur Maharashtra Site (TMS) coastal site using Metek GmbH, Ultra sonic anemometers are consistent with the proposed formula. In order to avoid self-correlation by using u, a new parameterization of w with ?u and ?v and gustiness parameter as given by Fairall et al. (1996) is used. The mean values of w and Z0fc estimated using new parameterization were observed to be 0.97 m/s and 2.3E-4 m respectively for the year 2009 at TMS. (author)
2010-05-13
Near term and future alternative clean vehicle technologies
Energy Technology Data Exchange (ETDEWEB)
Availability of a natural gas-powered van that meets California`s ultra low emission vehicle requirements and has a 300-km range was reported. A similar van with an electric system giving a range of 240 km was also within sight. Regarding the limitations of electric batteries it was suggested that a super capacitor may allow systems to achieve higher energy densities; a refuelable zinc-air battery could be considered for vehicle use. While the prospect for emissions improvement of gasoline vehicles has clearly improved in recent years, the relative costs of infrastructure, vehicle and fuel for the the alternative fuels compared with gasoline demonstrate the difficulty the alternative fuels have in taking market share from gasoline. For the next decade, gasoline, propane and CNG are expected to be the dominant fuels for vehicles. After that, the leading fuel will be the one that has been most extensively researched and developed during the decade. 17 refs.
1994-12-31
Mesodynamics in the SARS nucleocapsid measured by NMR field cycling
Energy Technology Data Exchange (ETDEWEB)
Protein motions on all timescales faster than molecular tumbling are encoded in the spectral density. The dissection of complex protein dynamics is typically performed using relaxation rates determined at high and ultra-high field. Here we expand this range of the spectral density to low fields through field cycling using the nucleocapsid protein of the SARS coronavirus as a model system. The field-cycling approach enables site-specific measurements of R{sub 1} at low fields with the sensitivity and resolution of a high-field magnet. These data, together with high-field relaxation and heteronuclear NOE, provide evidence for correlated rigid-body motions of the entire {beta}-hairpin, and corresponding motions of adjacent loops with a time constant of 0.8 ns (mesodynamics). MD simulations substantiate these findings and provide direct verification of the time scale and collective nature of these motions.
2009-09-15
Manganese oxide nanowires, films, and membranes and methods of making
Energy Technology Data Exchange (ETDEWEB)
Nanowires, films, and membranes comprising ordered porous manganese oxide-based octahedral molecular sieves, and methods of making, are disclosed. A single crystal ultra-long nanowire includes an ordered porous manganese oxide-based octahedral molecular sieve, and has an average length greater than about 10 micrometers and an average diameter of about 5 nanometers to about 100 nanometers. A film comprises a microporous network comprising a plurality of single crystal nanowires in the form of a layer, wherein a plurality of layers is stacked on a surface of a substrate, wherein the nanowires of each layer are substantially axially aligned. A free standing membrane comprises a microporous network comprising a plurality of single crystal nanowires in the form of a layer, wherein a plurality of layers is aggregately stacked, and wherein the nanowires of each layer are substantially axially aligned.
2008-10-21
Energy Technology Data Exchange (ETDEWEB)
Ultra-thin, uniform, pinhole-free solid polymer electrolyte films having a fixed carboxylic ester group of approximately 1 {mu}m thickness were prepared by polymerization of methyl acrylate and tris(2-methoxyethoxy)vinylsilane in a glow discharge plasma. The carboxylic ester group of the plasma polymer were transformed to lithium carboxylate groups by treatment with lithium iodide. This process give a single lithium ion conductive film. These solid polymer electrolyte films showed ionic conductivities of the order of 10{sup -8} S cm{sup -1} (10{sup 4} {omega} cm{sup 2} resistance per unit area) at room temperature. (orig.).
1990-08-01
Influence of Population III stars on cosmic chemical evolution
British Library Electronic Table of Contents (United Kingdom)
ABSTRACT New observations from the Hubble Ultra Deep Field suggest that the star formation rate at Formula Not Shown drops off faster than previously thought. Using a newly determined star formation rate for the normal mode of Population II/I (PopII/I) stars, including this new constraint, we compute the Thomson scattering optical depth and find a result that is marginally consistent with Wilkinson Microwave Anisotropy Probe 5 results. We also reconsider the role of Population III (PopIII) stars in light of cosmological and stellar evolution constraints. While this input may be needed for reionization, we show that it is essential in order to account for cosmic chemical evolution in the early universe. We investigate the consequences of PopIII stars on the local metallicity distribution fu...
2009-01-01
The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional and multi-component seismic area is being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil-in-place will result in additional oil production by primary and enhanced recovery processes.
1996-02-01
Energy Technology Data Exchange (ETDEWEB)
The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in Red River and Ratcliffe shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing three-dimensional and multi-component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short-radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil in place will result in additional oil recovery by primary and enhanced recovery processes.
1995-09-01
The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in Red River and Ratcliffe shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing three-dimensional and multi-component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short-radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil in place will result in additional oil recovery by primary and enhanced recovery processes.
1996-09-01
Identification of fatigue damage in cortical bone by diffraction enhanced imaging
International Nuclear Information System (INIS)
In an effort to explore Diffraction Enhanced Imaging of bone tissue, experiments were performed to determine if it was possible to use Diffraction Enhanced Imaging to detect microdamage in bovine cortical bone. Measurements were made at the National Synchrotron Light Source where pre- and post-fatigue rocking curve widths of the bone were studied. The rocking curve widths were then compared. Since no consistent pattern of narrowing or broadening of the rocking curve emerged, it is likely that the ultra-small-angle X-ray scattering present in the bone overshadowed any additional changes to rocking curve caused by microdamage of the bone. Larger bone structures were able to be visualized which suggests that microdamage may be visualized with a higher resolution detector.
2005-08-11
Hot dip galvanised dual phase steels for automotive applications
Energy Technology Data Exchange (ETDEWEB)
The automotive industry desires to optimize safety and lightweight construction for the production of cars and trucks. The resulting task for steel suppliers is to make steel grades available that can fulfil these requirements. Different projects have shown optimistic outlooks for optimization of safety and reduction of the weight of automobile bodies by using different high strength and ultra high strength steels. In the last group the dual phase steels play the lead. In recent years different steel grades have been developed and optimized for these applications. On one hand developing the mechanical properties as well as joining and forming of dual phase steels is one of the first steps. On the other hand different coated surfaces for various applications of dual phase steels is another step. Starting with characteristic production conditions for cold rolled hot dip galvanised dual phase steels, the mechanical properties for joining and forming will be deduced ...
2005-07-01
High-temperature property data: Ferrous alloys
Energy Technology Data Exchange (ETDEWEB)
In this book over 250 alloys are organized by AISI number into 10 major sections: Irons, Carbon Steels, Alloy Steels, Low Alloy Constructional Steels, Ultra High Strength Steels, Tool Steels, Maraging Steels, Wrought Stainless Steels, Heat Resistnat Casting Alloys, and Iron Based Rought Superalloys. Each alloy record lists the designation, specifications, UNS number, composition, product forms and a comment on the high-temperature properties and applications. Referenced data is then given for physical properties such as density, specific heat, thermal conductivity, thermal expansion, electrical conductivity, Poisson's ratio, moduli of elasticity and rigidity, etc. Mechanical properties follow, and include tensile properties, shearing and bearing properties, impact properties, creep, stress rupture and stress relaxation and fatigue properties. The last part of the alloy record gives other effects of temperature, such as hot hardness, corrosion, and growth.
1987-01-01
Friction in ultra-thin conjunction of valve seals of pressurised metered dose inhalers
British Library Electronic Table of Contents (United Kingdom)
In many drug dispensing devices, such as syringes and inhalers, an elatomeric gasket is used to prevent the formulation from leaking from the chamber. During device actuation, the seal is subjected to friction, which in turn causes its deformation and can cause unintentional leakage, thus dose variability. Additionally, friction of seal is responsible for a host of potential problems such undue effort required for actuation and potential wear. The mechanism of friction generation in the seal conjunction is complex, arising from adhesion of rubber in contact with the moving interface, viscous action of a thin film of fluid and deformation of seal asperities. Therefore, the first step in understanding the conjunctional behaviour of rubber seals is a fundamental study of mechanisms of frictio...
2010-01-01
Empirical regularities of order placement in the Chinese stock market
Using ultra-high-frequency data extracted from the order flows of 23 stocks traded on the Shenzhen Stock Exchange, we study the empirical regularities of order placement in the opening call auction, cool period and continuous auction. The distributions of relative logarithmic prices against reference prices in the three time periods are qualitatively the same with quantitative discrepancies. The order placement behavior is asymmetric between buyers and sellers and between the inside-the-book orders and outside-the-book orders. In addition, the conditional distributions of relative prices in the continuous auction are independent of the bid-ask spread and volatility. These findings are crucial to build an empirical behavioral microscopic model based on order flows for Chinese stocks.
2007-01-01
Embedded systems for vacuum control at PEFP
International Nuclear Information System (INIS)
Development of a front end system for a high energy proton accelerator is in progress at Korea Atomic Energy Research Institute (KAERI) for basic science and industrial applications. The proper vacuum components has been installed and operated successfully between ion source and RFQ. The reliable operation of the accelerator has been completed at vacuum system in the high and ultra high vacuum range under operating conditions. Proper control system for the vacuum instruments, based on PC operated by Windows, has been designed and constructed by control group at PAL. As PC operated by windows with inherent instability does not proper, embedded system can be replaced for reliable operation system, such as VME system operated by vxWorks.
2005-05-26
Effects of C-60 fullerenes and carbon nanotubes on marine mussels.
Environmental Research Database
Objectives1. We will use reduction of lysosomal stability as an indicator of cell injury induced by C-60 fullerenes and carbon nanotubes in the liver analogue or digestive gland (hepatopancreas) of marine mussels. Molluscan hepatopancreatic digestive cells are key to normal function and are a sensitive key interface with the environment. Reduction of lysosomal stability is mechanistically linked with impaired health of the whole animal. 2. We will also test the hepatopancreatic digestive cells for evide [continued...]DescriptionNanotechnology is a major innovative scientific and economic growth area, which may present a variety of hazards for environmental and human health. The surface properties and very small size of nanoparticles and nanotubes provides surfaces that may bind and transport toxic chemical pollutants, as well as possibly being toxic in their own right by generating reactive oxygen species (ROS). There is a wealth of evidence for the harmful effects of nanoscale ...
2008-01-25
Double plasma mirror for ultrahigh temporal contrast ultra-intense laser pulses
International Nuclear Information System (INIS)
We present and characterize a very efficient optical device that employs the plasma mirror technique to increase the contrast of high-power laser systems. Contrast improvements higher than 104 with 50% transmission are shown to be routinely achieved on a typical 10 TW laser system when the pulse is reflected on two consecutive plasma mirrors. Used at the end of the laser system, this double plasma mirror preserves the spatial profile of the initial beam, is unaffected by shot-to-shot fluctuations, and is suitable for most high peak power laser systems. We use the generation of high-order harmonics as an effective test for the contrast improvement produced by the double plasma mirrors. (authors)
International Nuclear Information System (INIS)
The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)
1999-08-22
Energy Technology Data Exchange (ETDEWEB)
The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)
1999-08-01
COSY synchrotron and storage ring for medium energy physics
Energy Technology Data Exchange (ETDEWEB)
At present the cooler synchrotron COSY a synchrotron and storage ring for medium energy physics is being commissioned at Juelich. The construction of the ring was finished during September 1992. The cooler ring will deliver protons in the momentum range from 270 to 3300 MeV/c. The phase density of the circulating protons will be increased with electron cooling at injection and with stochastic cooling at momenta between 1500 and 3300 MeV/c. High luminosity internal experiments as well as high resolution external experiments will be possible. Details of the lattice, to match the different ion optical requirements for cooling, acceleration, internal experiments and ultra-slow extraction will be discussed. An overview of the performance of the ion sources, the injector cyclotron, the ring, the injection beamline are given. The realization status of the extraction beamlines to the external experimental area is given. The experience on the commissioning of the cooler ...
1993-01-01
Boron-enhanced-diffusion of boron: The limiting factor for ultra-shallow junctions
Energy Technology Data Exchange (ETDEWEB)
Reducing implant energy is an effective way to eliminate transient enhanced diffusion (TED) due to excess interstitials from the implant. It is shown that TED from a fixed Si dose implanted at energies from 0.5 to 20 keV into boron doping-superlattices decreases linearly with decreasing Si ion range, virtually disappearing at sub-keV energies. However, for sub-keV B implants diffusion remains enhanced and x{sub j} is limited to {ge} 100 nm at 1,050 C. The authors term this enhancement, which arises in the presence of B atomic concentrations at the surface of {approx} 6%, Boron-Enhanced-Diffusion (BED).
1997-12-01
Advanced Neutron Source: Plant Design Requirements
Energy Technology Data Exchange (ETDEWEB)
The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and ...
1990-07-01
Seismic line across Wind River thrust fault, Wyoming
Energy Technology Data Exchange (ETDEWEB)
A seismic line was acquired by ARCO Exploration Company in 1977 in southern Freemont County and extends northeast from the deepest part of the Green River basin across the Wind River thrust onto crystalline basement rocks of the Wind River Mountains. A COCORP line across the area has been discussed previously, but the ARCO line shows more detailed information beneath the thrust. The seismic line is significant because it shows a strong reflection at the base of the Precambrian granite, which overlies a sedimentary rocks of the northern Green River basin. It also illustrates an apparent anticline beneath the thrust fault which is the result of lateral velocity variation caused by a shallow wedge of low-velocity Miocene sediments superimposed on a velocity pull-up related to the high-velocity Precambrian granite. The effects of the velocity variations can be analyzed by ray tracing and by studying the near offset and far offset stacks of the seismic data. A ...
1985-05-01
Energy Technology Data Exchange (ETDEWEB)
A new method for the preconcentration and determination of trace amounts of lead at the {mu}g/L level in natural waters has been established based on the formation of the thenoyltrifluoroacetone (TTA) complex with dibenzo-18-crown-6 (DB18C6) by means of synergistic extraction and back-extraction combined with atomic absorption spectrometry (AAS). The effect of various factors (synergism with TTA and DB18C6, shaking time, preconcentration factor, composition of the extracted species, and foreign ions etc.) on the extraction and back-extraction of lead has been investigated in detail. The lead-TTA chelate in o-dichlorobenzene forms a stable adduct with DB18C6 as Pb(TTA){sub 2} DB18C6. The stability constant ({beta}) of the adduct determined by curve fitting method was log {beta} = 4.2. The amount of lead in natural waters such as tap water (Kanazawa University) and Kakehashi river (Komatsu City) determined by the present method was found to be 0.64 {+-} 0.02 {mu}g/L ...
1998-07-01
Optimal alignment of mirror based pentaprisms for scanning deflectometric devices
In the recent work [Proc. of SPIE 7801, 7801-2/1-12 (2010), Opt. Eng. 50(5) (2011), in press], we have reported on improvement of the Developmental Long Trace Profiler (DLTP), a slope measuring profiler available at the Advanced Light Source Optical Metrology Laboratory, achieved by replacing the bulk pentaprism with a mirror based pentaprism (MBPP). An original experimental procedure for optimal mutual alignment of the MBPP mirrors has been suggested and verified with numerical ray tracing simulations. It has been experimentally shown that the optimally aligned MBPP allows the elimination of systematic errors introduced by inhomogeneity of the optical material and fabrication imperfections of the bulk pentaprism. In the present article, we provide the analytical derivation and verification of easily executed optimal alignment algorithms for two different designs of mirror based pentaprisms. We also provide an analytical description for the ...
2011-03-04
Kinetics of absorption of trace iodine vapor in aqueous solution of sodium hydroxide, (2)
International Nuclear Information System (INIS)
A liquid column was used for the experiments reported in Part 1. However, it only gives the observation of the effect of fast reaction because the liquid flow was controlled to uniform laminar flow and the contact is limited to short time of around 10 ms. In practical absorbing operation, turbulence is involved in liquid flow, and the residence time for contact is long. Hence, the absorption of trace iodine in the purified air has been experimented by using a constant interface area type stirred absorption tank. Prior to the experiment, the characteristics of the absorption tank was investigated by conducting pure carbon dioxide absorption test with purified water. It gave the conclusion that the tank was sufficiently usable for fundamental researches. In short contact time absorption, the iodine dissolved and absorbed in liquid phase is affected by reaction of hypoiodous acid and poly-iodide ion formation due to hydrolysis by basic catalyst, proceeding in the ...
1978-01-01
Bioaccumulation of trace metals in farmed fish from South China and potential risk assessment
British Library Electronic Table of Contents (United Kingdom)
Concentrations of trace metals were determined in water, sediment, fish feed and two species of farmed fish, pompano and snapper, collected from Daya Bay and Hailing Bay of South China in July 2007 and January 2008. Total average concentrations of Cu, Pb, Zn, Cd, Cr, Hg and As were 1.6, 2.7, 27.3, 0.025, 0.62, 0.18 and 0.59?g/gdrywt in pompano and 1.5, 2.6, 23.6, 0.020, 0.55, 0.22 and 0.53?g/gdrywt in snapper. In general, the concentrations of all target metals except Hg were positively correlated with lipid contents whereas negative correlations were observed between the metal concentrations and fish body weights. Model calculation indicated that dietary uptake of Zn and Cd predominate their accumulation in snapper, accounting for 99.9% and 98.2% of the total inputs. Risk ...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The atmosphere and the biosphere are inherently coupled to one another. Atmospheric surface state variables such as temperature, winds, water vapor, precipitation, and radiation control biophysical, biogeochemical, and ecological processes at the surface and subsurface. At the same time, surface fluxes of momentum, moisture, heat, and trace gases act as time-dependent boundary conditions providing feedback on atmospheric processes. To understand such phenomena, a coupled set of interactive models is required. Costs are still prohibitive for computing surface/subsurface fluxes directly for medium-resolution atmospheric general circulation models (AGCMs), but a technique has been developed for testing large-scale homogeneity and accessing surface parameterizations and models to reduce this computational cost and maintain accuracy. This modeling system potentially bridges the observed spatial and temporal ranges yet allows the incorporation of necessary details about ...
1993-12-31
Tracing of salicylic acid additive during precipitation of zirconium
International Nuclear Information System (INIS)
This paper presents the results of experimental study carried out to know whether the salicylic acid used as an additive during the precipitation of zirconium using ammonium hydroxide solution goes into the filtrate, remains in the hydrated zirconia or gets distributed between the both under the ambient conditions of precipitation. Keeping its simplicity and amenability to adopt on a routine basis, spectrophotometric method has been chosen for the purpose among the many methods available and the problems associated in determining salicylic acid in the presence of zirconium and the medial measures to circumvent the same have been brought out in detail. (author)
2011-02-22
International Nuclear Information System (INIS)
The methodology for studying the behaviour of the toxic pollutant metals (Hg, Pb, Cd, Cr) in the South Shetland region is presented here, toxic pollutants are caused by the urban and industrial activity at the Southern hemisphere and they are pressured to be incorporated to the region though atmospheric transport processes the Cs 137 (refI) was used as a tracing element, which was freed and dispersed in the atmosphere as a result of nuclear bombs testing. During the austral summer samples from ground, sediments, atmospheric and glacier were extracted.
Safety design guide for pipe rupture protection for CANDU 9
Energy Technology Data Exchange (ETDEWEB)
This safety design guide for pipe rupture protection identifies high-energy systems in which pipe ruptures must be postulated to occur, as well as systems that must be protected from the dynamic effects of such ruptures. Dynamic effects considered in this SDG consist of pipe whip (including missiles generated by pipe ruptures, if any) and jet impingement, Requirements for protection against the dynamic effects of a postulated pipe rupture and method of protection of essential structures, systems and components are specified for these effects. The change status for the regulatory requirements, code and standards should be traced and this safety design guide shall be updated accordingly. 2 tabs., 5 refs. (Author) .new.
1996-03-01
Recovery of rare earths from red mud
International Nuclear Information System (INIS)
The prospect for the recovery of rare earths from red mud, the bauxite tailings from the production of alumina is examined. The Jamaican red mud by far has the higher trace concentrations of lanthanum, cerium, neodymium, and yttrium. Scandium is also present. The dissolution of the rare earth is a major extraction problem because of the large volume of other materials. The recovery processes that have been proposed include the production of co-products such as iron, alumina, and titanium concentrates, with the rare earths going with the titanium. In this paper a critical examination of the possible processes are presented with the recommended research projects to be carried out.
1992-03-01
Probable role of trace elements of some medicinal plants in cardio-vascular diseases
International Nuclear Information System (INIS)
A number of herbal drugs are used in the Unani (Greco-Arab) System of Medicine for cardiovascular diseases. The herbs were analyzed by flame AAS and ICP-AES to determine if their therapeutic actions can be associated with the elements present in them. Cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, sodium, nickel, phosphorus, lead and zinc were some of the elements which play various roles in cardiovascular affections. An effort was made to correlate the role of these elements in cardiac diseases. (Auth.). 2 tabs., 32 refs.
International Nuclear Information System (INIS)
The purpose of the Ocean FUSRAP Program, which began in March 1981, is to assess the technical, environmental, and institutional feasibility of disposing, in the ocean and on the ocean floor, of FUSRAP waste which contains traces of natural radioactive materials. The initial planning has focused on the Middlesex, New Jersey, Sampling Plant site and surrounding properties, which contain on the order of 100,000 metric tons of material. The Belgian Congo uranium ore and other uranium ores used by the United States were handled at the sampling plant site and have since been removed.
Numerical study of Cosmic Ray Diffusion in MHD turbulence
We study diffusion of Cosmic Rays (CRs) in turbulent magnetic fields using test particle simulations. Electromagnetic fields are produced in direct numerical MHD simulations of turbulence and used as an input for particle tracing, particle feedback on turbulence being ignored. Statistical transport coefficients from the test particle runs are compared with earlier analytical predictions. We find qualitative correspondence between them in various aspects of CR diffusion. In the incompressible case, that we consider in this paper, the dominant scattering mechanism occurs to be the non-resonant mirror interactions with the slow-mode perturbations. Perpendicular transport roughly agrees with being produced by magnetic field wandering.
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
The Monte Carlo ray-tracing method is applied and coupled with optical properties to predict the radiation performance of solar concentrator/cavity receiver systems. Several different cavity geometries are compared on the radiation performance. A flux density distribution measurement system for dish parabolic concentrators is developed. The contours of the flux distribution for target placements at different distances from the dish vertex of a solar concentrator are taken by using an indirect method with a Lambert and a charge coupled device (CCD) camera. Further, the measured flux distributions are compared with a Monte Carlo-predicted distribution. The results can be a valuable reference for the design and assemblage of the solar collector system.
2010-01-01
Microstructure, texture and mechanical properties of the magnesium alloy AZ31 processed by ECAP
Energy Technology Data Exchange (ETDEWEB)
To investigate the influence of equal channel angular pressing on the microstructure and texture of the magnesium alloy AZ31, electron backscattering diffraction and well as neutron diffraction experiments were carried out. Through these experiments it was possible to trace the microstructure and texture evolution with strain accumulated with the increasing number of equal channel angular pressing passes. It was further demonstrated by subsequent compression tests that the microstructural changes produced by equal channel angular pressing have a beneficial effect on both the compressive strength and ductility of AZ31. (orig.)
2008-01-15
Longitudinal emittance oscillation in a superconducting drift tube linac
International Nuclear Information System (INIS)
In drift tube linacs a beam energy spread results form the finite beam size. Radial variation of the axial accelerating field induces a beam energy spread, which, in general, will accumulate as the beam passes through successive drift tubes. This paper shows that under some conditions of periodic transverse focusing and longitudinal phase focusing, the correlation between the longitudinal and transverse motion can be used to correct the energy spread. The process of achieving such a correction is first described in a simplified situation, and then demonstrated for a particular tuning using a ray-tracing program which models a low velocity and low charge state linac designed for radioactive ion beams.
1995-05-01
Interferometry and refraction measurements in plasmas of elliptical cross-section
Energy Technology Data Exchange (ETDEWEB)
The measurement of electron densities using interferometry and refraction measurements in plasmas with cross-sections where the electron density contours are concentric ellipses is examined. Transforms are found for both interferometrically deduced optical path-length differences and refraction angle data obtained from elliptical cross-section plasmas. The transformed data can be inverted to give electron densities using standard techniques developed for circular cross-section plasmas. Refraction of light in elliptical cross-section plasmas is examined using numerical ray tracing.
1984-04-14
This bulletin traces development of high-pressure, coal and tar hydrogenation technology, based on an intensive review of pertinent literature. The bulletin written as part of the Bureau of Mines research program on synthetic liquid fuels covers the history and economics of the process; chemical aspects of hydrogenation of coal, tar, and middle oil; engineering aspects of converting coal and tar to liquid fuels, principally gasoline; and equipment for the process. The literature covered includes documents of United States and British governments, journals, and other publications. Bureau results in the hydrogenation field are also incorporated.
1968-01-01
Employment of /sup 203/Pb isotoic solution without a carrier for erythrocyte tracing
Energy Technology Data Exchange (ETDEWEB)
Possibilities of applying the Pb/sup 203/ isotonic solution without a carrier as a label of blood erythrocytes, are found. There is a number of advantages in the Pb/sup 203/ isotonic solution without a carrier, such as a high label efficiency (above 95%), a short half-life (52 hours), and a low radiation dose. These factors prove to be favourable as compared with Cr/sup 51/ widely used for these purposes. Besides, of all preparations used up to now to treat erythrocytes and to scan the spleen, it is only in the case of Pb/sup 203/ isotonic solution without a carrier that no weight amounts of chemical substances do not enter the organism.
1981-08-01
International Nuclear Information System (INIS)
Iodine deficiency disorders (IDD) are one of most common nutritional deficiencies in the world. The nuclear analytical methods (ENAA, SRXRF and XRF) were employed to study the effect of iodine deficiency on the metal ion changes during the stage of brain development, combined with biochemical methods. The results show that the distributions of iron, copper and zinc varied to different extent in different brain regions and subcellular fractions of the ID rat brains. These distributional changes of trace elements might be associated with the brain damage caused by the iodine deficiency. (author)
2006-09-01
Discrete simulation of power law noise
A method for simulating power law noise in clocks and oscillators is presented based on modification of the spectrum of white phase noise, then Fourier transforming to the time domain. Symmetric real matrices are introduced whose traces--the sums of their eigenvalues--are equal to the Allan variances, in overlapping or non-overlapping forms, as well as for the corresponding forms of the modified Allan variance. Diagonalization of these matrices leads to expressions for the probability distributions for observing a variance at an arbitrary value of the sampling or averaging interval $\\tau$, and hence for estimating confidence in the measurements. A number of applications are presented for the common power-law noises.
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The authors trace the early history of nuclear power regulation in the US. Focusing on the Atomic Energy Commission, they describe the role of other groups that figured in the development of regulatory policies, including the Congressional Joint Committee on Atomic Energy, other federal agencies, state governments, the nuclear industry, and scientific organizations. They consider changes in public perceptions of and attitudes toward atomic energy and the dangers of radiation exposure. The basic purpose of the book is to provide the Nuclear Regulatory Commission and the general public with information on the historical antecedents and background of regulatory issues so that there will be continuity in policy decisions. The book concludes with an annotated bibliography of selected references. 19 figures.
1984-01-01
Calculation of ice accumulation rates in Antarctica over the last glacial cycle.
Environmental Research Database
DescriptionRates of ice accumulation in Antarctica are not known well, yet they are fundamental to assessing the ice sheet mass balance. Past accumulation rates are less well defined. We are in a unique position to provide detailed accounts of accumulation in Antarctica. We will measure isochronous internal layering across the ice sheet, which can be readily identified in radar data that we hold. Internal layers will be traced to ice-cores (allowing dating) and across wide regions of the ice sheets. A nume [continued...
2006-01-08
Brittle fracture problem in composite insulators
Energy Technology Data Exchange (ETDEWEB)
The report traces the documented incidences of brittle fracture in composite suspension insulators for use on high voltage transmission lines, and presents the subsequent investigations. It describes the part played by electrical activity, stress corrosion and humidity, and compares similar failures that have taken place in electric traction insulators. It then goes on to review related work on the humidity effects, stress corrosion, fatigue and partial discharges in glass fiber reinforced plastics in general. The final section summarizes the present understanding of the problem and the various measures taken by different manufactures to avoid it in the future. The need for acceptance criteria in this respect is outlined.
1984-04-01
Trace elements in the Allende meteorite
International Nuclear Information System (INIS)
New RNAA determinations of Ba, Sr, Zr, U, Re, Pd, Ag, Zn and Se and INAA measurements of Lu are added to published data for 21 other elements in the same suite of ten samples. On the average, 21 refractory elements are not significantly fractionated from one another. The mean of their enrichment factors relative to C1 chondrites is 17.5 +- 0.4, indicating that the high-temperature condensate inclusions represent 5.7 wt% of the total condensable matter. Os, Ir, Ru, Re and most of the W condensed in one or more refractory siderophile element alloys along with small fractions of the Pd, Co, Au and Ag. The bulk of the Eu and Sr condensed in solid solution in melilite. Sc, Zr, Hf, Ta, U and the remaining REE condensed in a phase whose abundance in the inclusions in negatively correlated with that of melilite, either diopside or one or more minor or trace phases, including perovskite. Ba condensed in a different phase, separately from all these elements. In individual ...
1977-01-01
Simultaneous estimation of trace and toxic metals through drinking water from Tarapur using ICP-AES
International Nuclear Information System (INIS)
In the present paper the contamination levels of trace and toxic metals in drinking water collected from Tarapur industrial area, Thane were investigated. The concentrations of trace and toxic metals (Pb, Cd, Cu, Cr, Ni, Se, V, Zn, Mn, Mo, Co, As and Ba) were determined simultaneously using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The results were compared with international water quality guidelines (WHO, 2008) and were found within the permissible limits. The quality assurance was checked by standard addition method and spike recovery. The concentration of Pb, Cd, Cu, Cr, Ni, Se, V, Zn, Mn, Mo, Co, As and Ba varies from 4.25-19.62 #mu#g/L, 0.13-1.49 #mu#g/L, 0.60-65.55 #mu#g/L, 0.46-4.15 #mu#g/L, <0.1 #mu#g/L, 0.5- 9.35 #mu#g/L, <0.5 #mu#g/L, 3.41-99.64 #mu#g/L, 0.80-9.62 #mu#g/L, 0.30-1.48 #mu#g/L, <0.1-0.90 #mu#g/L, <0.63 #mu#g/L and 0.71-9.0 #mu#g/L respectively. Similarly Na, K, Ca and Mg varies from ...
2010-05-13
Numerical ray tracing of electrons in different 3D fringing fields of spherical deflectors
This paper presents the results of numerical investigations on electron trajectories in different 3D fringing fields of spherical defectors. We start with a chosen set of geometrical values for the electrodes such as radius of curvature, electrode gap, angle between entrance and exit face. We do a first numerical calculation of the spatial potential distribution using a 3D electron optics program based on the finite difference method (FDM). Ray tracing through this potential distribution is then performed using another program, which also gives the potential and the electric field strength along the curved beam path. In the next step we estimate the position and the geometry of the field clamp using Herzog's formulae assuming the entrance of a parallel plate condenser to be a good approximation for the entrance of the spherical deflector in first order. For the consecutive numerical recalculations of the real potential distribution of the spherical deflector with ...
1999-11-01
Energy Technology Data Exchange (ETDEWEB)
Dissolved humic substances (humic and fulvic acids) occur in surface waters and groundwaters in concentrations ranging from less than 1 mg(C)/L to more than 100 mg(C)/L. Humic substances are strong complexing agents for many trace metals in the environment and are also capable of forming stable soluble complexes or chelates with radionuclides. Concentrations of humic materials as low as 1 mg(C)/L can produce a detectable increase in the mobility of some actinide elements by forming soluble complexes that inhibit sorption of the radionuclides onto rock materials. The stability of trace metal- or radionuclide-organic complexes is commonly measured by an empirically determined conditional stability constant (K'), which is based on the ratio of complexed metal (radionuclide) in solution to the product concentration of uncomplexed metal and humic complexant. Larger values of stability constants indicate greater complex stability. The ...
1985-07-01
Energy Technology Data Exchange (ETDEWEB)
A high power (200KV), intense current density, low emittance (71mmmrad), high brightness (8x10{sup 10}A/m rad) electron beam was generated in the 10cm long, high-voltage-resistive multi-gap hollow cathode pseudospark chamber filled with 15pa nitrogen and driven by an improved pulse line accelerator. The beam was ejected with the 1mm diameter, the 2.2KA beam current, and the 400ns pulse length, and could propagated 20cm in the drift tube. At a distance of 5cm from the anode it penetrated consecutively an acid-sensitive discoloring film and a 0.05mm-thick copper foil both stuck closely, left 0.6mm and 0.3mm holes on them, respectively. That 10 shots on an acid-sensitive film produced a hole of 1.6mm at 7cm downstream of anode showed its good repeatability. After 60 shots the pseudospark discharge chamber was disassembled and observed that almost no destructive damage traces left on the surfaces of its various electrodes and insulators. But on almost all the surfaces ...
1995-12-31
International Nuclear Information System (INIS)
The physicochemical forms and partitioning of corrosion products released from stainless steel upon exposure to selected environmental conditions is the subject of this investigation. This report describes the influence of calcareous sediment on the rate of release and fate of corrosion products produced when neutron-activated stainless steel specimens were exposed to a Globigerina ooze taken from the Northeast Pacific Ocean. The calcareous ooze used in this study consists largely of planktonic formanifera tests and was found to be about 90% CaCO_3. The trace metal content of this sediment was typical of average deep-sea carbonate sediments, and the ratios of trace elements to Ti were not remarkably different from a coastal clayey silt or a Northeast Pacific pelagic red clay. Most (>80%) of the trace metals extracted by sequential chemical treatment were associated with reductant-soluble materials, i.e., amorphous Mn and ...
International Nuclear Information System (INIS)
Tritium occurs in nature in trace amounts, but its concentration is changing due to natural and artificial sources. Studies focusing on natural tritium have to take into account the effect of artificial sources. Also, the impact of tritium is an important issue in environmental protection, e.g. in connection with the emissions from nuclear power plants. The present work focuses on the rain washout of tritium emitted from the Paks nuclear power plant in Hungary. Rainwater collectors were placed around the plant and after a period of precipitation, rainwater was collected and analysed for tritium content. Samples were analysed using low-level liquid scintillation counting, with some also subject to the more accurate "3He ingrowth method. The results clearly show the trace of the tritium plume emitted from the plant; however, values are only about one order of magnitude higher than environmental background levels. A washout model was devised to ...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
A transplant experiment was conducted to determine whether standard metabolic rate (SMR) of a freshwater shrimp (Palaeomonetes paludosus) would be affected by exposure to trace element-enriched coal combustion waste (coal ash). Shrimp were transplanted into replicate cages in a coal ash-polluted site and a reference site for 8 months. The coal ash-polluted site was characterized by elevated sediment concentrations of As, Cd, Cr, Cu, Ni, Pb and Se compared to sediments in the reference site. After 8 months in the study sites, shrimp in the polluted site appeared to have accumulated As, Cd and Se from the habitat, but there were on differences in survival between the study sites. However, mean SMR of shrimp (measured as O{sub 2} consumption at rest) held in the polluted site was 51% higher than mean SMR of shrimp held in the reference site. The elevation in SMR indicates that the energetic costs of maintenance are greater for shrimp chronically exposed to the ...
1998-12-01
ARM AND INTERARM STAR FORMATION IN SPIRAL GALAXIES
International Nuclear Information System (INIS)
We investigate the relationship between spiral arms and star formation in the grand-design spirals NGC 5194 and NGC 628 and in the flocculent spiral NGC 6946. Filtered maps of near-IR (3.6 #mu#m) emission allow us to identify 'arm regions' that should correspond to regions of stellar mass density enhancements. The two grand-design spirals show a clear two-armed structure, while NGC 6946 is more complex. We examine these arm and interarm regions, looking at maps that trace recent star formation-far-ultraviolet (GALEX NGS) and 24 #mu#m emission (Spitzer SINGS)-and cold gas-CO (HERACLES) and H I (THINGS). We find the star formation tracers and CO more concentrated in the spiral arms than the stellar 3.6 #mu#m flux. If we define the spiral arms as the 25% highest pixels in the filtered 3.6 #mu#m images, we find that the majority (60%) of star formation tracers occur in the interarm regions; this result persists qualitatively even when considering the potential impact ...
2010-12-10
Energy Technology Data Exchange (ETDEWEB)
The development of new steels is always a challenge for the manufacturer of filler metals. In many cases it is obvious that some properties of the base metal cannot be fulfilled with matching filler metals. In some cases, dissimilar filler metals can solve the problem in some cases, there is no chance to meet the requirements of the base metal (for example yield strengths of new ultra high strength steels). This paper deals with different kinds of new steels and the requirements for the weld metal with examples from motor car industry (Mangan Austenite), crane (Ultra high strength steels), earthmoving machinery (Wear-resistant steels) and offshore (Supermartensitic steels). Specific problems will be discussed and best solutions will be highlighted. These examples make clear that the success of new kinds of steels in the market depends on solving the joining problems of these steels. (Abstract Copyright [2007], Wiley Periodicals, Inc.) [German] ...
2007-07-15
Ultra-high temperature strength properties on Mod.9Cr-1Mo steel
Energy Technology Data Exchange (ETDEWEB)
A sodium-water reaction drove from the single tube break in steam generator of FBR might overheat labor tubes rapidly under internal pressure loadings. If the temperature of tube wall becomes too high, it has to be evaluated that the stress of tube does not exceed the material strength limit to prevent the propagation of tube rupture. This study clarified the tensile and creep properties of Mod.9Cr-1Mo steel at ultra-high temperature which will be used in evaluation of the tube burst by sodium-water reaction. The strain rates for tensile test are from 10%/min to 10%/sec, and creep-rupture time is maximum 277sec. The range of test temperature is 700degC to 1300degC. The main results obtained were as follows; (1) The evaluation data on the relationship between tensile strength and strain rate and creep-rupture strength in shorter time on Mod.9Cr-1Mo steel were acquired. (2) Short-term mechanical properties of Mod.9Cr-1Mo steel were evaluated based on the results of ...
2000-03-01
Energy Technology Data Exchange (ETDEWEB)
Research highlights: {yields} The use of resonant photoemission in its 'core-hole clock' expression for the study of the dynamical charge transfer across hybrid organic-inorganic interfaces and for the intermolecular charge transfer in the bulk of organic thin films is reviewed. {yields} The electronic coupling to the substrate and the efficiency of charge transport across hybrid interfaces is different for individual electronic subsystems of the molecular adsorbate. {yields} The intermolecular charge transfer in the bulk of discotic liquid crystals occurs on the order of a few femtoseconds and is faster than expected from the macroscopic charge transport characteristics of the material. -- Abstract: The focus of this brief review is the use of resonant photoemission in its 'core-hole clock' expression for the study of two important problems relevant for the field of organic electronics: the dynamical charge transfer across hybrid organic-inorganic ...
2011-01-15
Energy Technology Data Exchange (ETDEWEB)
The high-strength and ultra high-strength steels developed and produced by Thyssen Krupp Stahl make a major contribution to automotive lightweighting. Proven and newly-developed coatings are used to meet increasingly important corrosion protection requirements. Design for materials, optimized forming and joining processes and the use of modern simulation techniques help to exploit the potential of the new steels. Future development work will focus on reducing the density of steels without compromising their well-known advantages - in particular their strength. The use of high-strength and ultra high-strength steels in the automotive industry is on the increase. Steel will remain the material of choice for auto manufacture, above all due to its potential for cost-efficient lightweight construction and its full recyclability. (orig.) [German] Einen wesentlichen Beitrag zum Leichtbau im Automobil leisten die von Thyssen Krupp Stahl entwickelten ...
1999-04-01
The steroidogenic factor 1 (SF-1, also known as NR5A1) is a transcription factor belonging to the nuclear receptor superfamily. Whereas most of the members of this family have been extensively characterized, the therapeutic potential and pharmacology of SF-1 still remains elusive. Described here is the identification and characterization of selective inhibitory chemical probes of SF-1 by a rational ultra-high-throughput screening (uHTS) strategy. A set of 64,908 compounds from the National Institute of Health's Molecular Libraries Small Molecule Repository was screened in a transactivation cell-based assay employing a chimeric SF-1 construct. Two analogous isoquinolinones, ethyl 2-[2-[2-(2,3-dihydro-1,4-benzodioxin-7-ylamino)-2-oxoethyl]-1-oxoisoquinolin-5-yl]oxypropanoate (SID7969543) and ethyl 2-[2-[2-(1,3-benzodioxol-5-ylmethylamino)-2-oxoethyl]-1-oxoisoquinolin-5-yl]oxypropanoate and (SID7970631), were identified as potent submicromolar inhibitors, yielding ...
2008-03-11
Energy Technology Data Exchange (ETDEWEB)
A comprehensive understanding of dopant activation mechanisms in crystalline Si is required in order to form shallow junctions. In this paper, we will review several experimental assessments on boron clustering and novel methods to form shallow junctions. Boron marker-layer structures have been used to investigate the fundamental aspects of formation and ripening boron-interstitial clusters (BICs) and their influence on the associated transient enhanced diffusion (TED). The samples were damaged by Si implants at different doses in the sub-amorphizing range and annealed at high temperatures. We found that BICs act as a sink for interstitials at supersaturations values S(t)>10{sup 4}. This implies that silicon self-interstitial defects are the primary source of interstitials driving TED, and that BICs act as a secondary 'buffer' for the interstitial supersaturation. These clusters are less sensitive to the ripening process than pure interstitial clusters do, so ...
2002-01-01
International Nuclear Information System (INIS)
Ultra-low pure Pt-based electrodes (0.04-0.12 mg_P_t/cm"2) were prepared by dual ion-beam assisted deposition (dual IBAD) method on the surface of a non-catalyzed gas diffusion layer (GDL) substrate. Film thicknesses ranged between 250 and 750 A, these are compared with a control, a conventional Pt/C (1.0 mg_P_t_(_M_E_A_)/cm"2, E-TEK). The IBAD electrode constituted a significantly different morphology, where low density Pt deposits (largely amorphous) were formed with varying depths of penetration into the gas diffusion layer, exhibiting a gradual change towards increasing crystalline character (from 250 to 750 A). Mass specific power density of 0.297 g_P_t/kW is reported with 250 A IBAD deposit (0.04 mg_P_t/cm"2 for a total MEA loading of 0.08 mg_P_t/cm"2) at 0.65 V. This is contrasted with the commercial MEA with a loading of 1 mg_P_t_(_M_E_A_)/cm"2 where mass specific power density obtained was 1.18 g_P_t/kW (at 0.65 V), a value typical of current state of the ...
2006-06-05
Experimental study of lipiodol ultra-fluid. On its signal intensity in MR imaging
Energy Technology Data Exchange (ETDEWEB)
Lipiodol Ultra-Fluid (Lipiodol) is widely applied in the transcatheter arterial embolization (TAE). We studied signal intensity, the T1 relaxation time and the T2 relaxation time of Lipiodol itself using Siemens Magnetom H15-2 T (1.5 Tesla) and Magnetom M10 (1.0 Tesla). Lipiodol showed higher signal intensity than saline solution on the T1-weighted images (short TR, short TE technique in spin echo method). On the T2-weighted images (long TR, long TE technique in spin echo method), Lipiodol showed lower signal intensity than saline solution. The T1 relaxation time of Lipiodol, measured at 1.0 T, was 201 msec and 218 msec at 1.5 T. The T2 relaxation time of Lipiodol, measured at 1.0 T, was 127 msec; and 167 msec at 1.5 T. The signal intensity of Lipiodol at 1.0 T was higher than the intensity at 1.5 T. Shorter T1 relaxation time of Lipiodol at 1.0 T is probably responsible for the higher intensity at 1.0 T. When MRI is performed after TAE with Lipiodol, the signal ...
1988-11-01
International Nuclear Information System (INIS)
Ultra low loading noble metal (0.04-0.12 mg_P_t/cm"2) based electrodes were obtained by direct metallization of non-catalyzed gas diffusion layers via dual ion beam assisted deposition (IBAD) method. Fuel cell performance results reported earlier indicate significant improvements in terms of mass specific power density of 0.297 g_P_t/kW with 250 A thick IBAD deposit (0.04 mg_P_t/cm"2 for a total MEA loading of 0.08 mg_P_t/cm"2) at 0.65 V in contrast to the state of the art power density of 1.18 g_P_t/kW using 1 mg_P_t_(_M_E_A_)/cm"2 at 0.65 V. In this article we report the peroxide radical initiated attack of the membrane electrode assembly utilizing IBAD electrodes in comparison to commercially available E-TEK (now BASF Fuel Cell GmbH) electrodes and find the pathway of membrane degradation as well. A novel segmented fuel cell is used for this purpose to relate membrane degradation to peroxide generation at the electrode/electrolyte interface by means of ...
2009-11-01
Edge biasing in the WEGA stellarator
Energy Technology Data Exchange (ETDEWEB)
The WEGA stellarator is used to confine low temperature, overdense (densities exceeding the cut-off density of the heating wave) plasmas by magnetic fields in the range of B=50-500 mT. Microwave heating systems are used to ignite gas discharges using hydrogen, helium, neon or argon as working gases. The produced plasmas have been analyzed using Langmuir and emissive probes, a single-channel interferometer and ultra-high resolution Doppler spectroscopy. For a typical argon discharge in the low field operation, B=56 mT, the maximum electron density is n{sub e}{proportional_to}10{sup 18} m{sup -3} with temperatures in the range of T=4-12 eV. The plasma parameters are determined by using Langmuir probes and are cross-checked with interferometry. It is demonstrated within this work that the joint use of emissive probes and ultra-high resolution Doppler spectroscopy allows a precise measurement of the radial electric field. The focus of this work is ...
2009-02-27
Development of a dedicated ethanol ultra-low emission vehicle (ULEV) system design
Energy Technology Data Exchange (ETDEWEB)
The objective of this 3.5 year project is to develop a commercially competitive vehicle powered by ethanol (or ethanol blend) that can meet California`s ultra-low emission vehicle (ULEV) standards and equivalent corporate average fuel economy (CAFE) energy efficiency for a light-duty passenger car application. The definition of commercially competitive is independent of fuel cost, but does include technical requirements for competitive power, performance, refueling times, vehicle range, driveability, fuel handling safety, and overall emissions performance. This report summarizes a system design study completed after six months of effort on this project. The design study resulted in recommendations for ethanol-fuel blends that shall be tested for engine low-temperature cold-start performance and other criteria. The study also describes three changes to the engine, and two other changes to the vehicle to improve low-temperature starting, efficiency, and emissions. ...
1995-02-01
The analysis of biological and environmental samples for lead by photon activation
International Nuclear Information System (INIS)
... activation analysis biological materials bremsstrahlung environment lead lead
STRESS ANALYSIS OF AN AUTOFRETTAGED LOOSE ...
... Title : STRESS ANALYSIS OF AN AUTOFRETTAGED LOOSE LINER FOR GUN BARREL CONSTRUCTION PRECOMPRESSED IN THE ...
1969-09-16
Radionuclide X-ray fluorescence analysis. 3: Examples of application in practice
Examples are given of the applicability and importance of radionuclide fluorescence analysis as a
1973-01-01
Determination of nanogram quantities of lead by photon activation analysis
International Nuclear Information System (INIS)
... activation analysis bremsstrahlung environment gamma spectroscopy
SPARSE SUPERPIXEL UNMIXING FOR EXPLORATORY - NASA
Fast automated analysis of hyperspectral imagery can inform ... hyperspectral image analysis. .... atmospheric correction with the Crism Analysis Tool [11]. ...
Proteinortho: Detection of (Co-)orthologs in large-scale analysis
UK PubMed Central (United Kingdom)
BackgroundOrthology analysis is an important part of data analysis in many areas of bioinformatics such as comparative genomics and molecular phylogenetics. The ever-increasing flood...Full Text Available
UK PubMed Central (United Kingdom)
This article proposes Bayesian analysis of mediation effects. Compared to conventional frequentist mediation analysis, the Bayesian approach has several advantages. First, it allows researchers...Full Text Available
2009-12-01
XPS/AES Study of Electrical and Chemical Properties of Pd/SiC Interface
Silicon carbide (SiC) based electronic devices are of great importance for applications under the condition of high temperature, high power and high radiation. Schottky diodes of Palladium/SiC are good candidates for hydrogen and hydrocarbon gas sensors at elevated temperature. The detection sensibility of the diodes has been found heavily temperature dependent. In this work, the electrical and chemical properties of Pd/SiC Schottky contacts were studied by XPS and AES at different annealing temperatures. Schottky diodes were made by depositing ultra-thin palladium films onto a silicon carbide substrate. No significant change in the Schottky barrier height of the Pd/SiC contact was found in the temperature range of 300-673K. Palladium diffusion into SiC and the formation of palladium silicides were observed at room temperature and became significant at 300^oC and higher temperature. The mechanism of diffusion and reaction at the Pd/SiC interface will be discussed. ...
1997-11-01
Weldability of high strength Ni-based alloy USC141 as boiler tube for 700 C USC plant
Energy Technology Data Exchange (ETDEWEB)
Recently the increase of steam temperature and pressure of power plant is required to enhance the thermal efficiency and reduce the CO{sub 2} emission. For the application to advanced USC (Ultra Super Critical) boiler with steam temperature around 700 C, the application of Ni-based alloy such as Alloy617 will be necessary. A new Ni-based alloy USC141 (20Cr-10Mo-2Ti-Al-bal.Ni) with excellent creep rupture strength and low thermal expansion has been developed by Hitachi Ltd. and Hitachi Metals Ltd. as the candidate material for 700 C USC turbine components. In present work, to investigate the possibility for boiler tube application of USC141, its weldability and high temperature strength properties were experimentally examined. The tested material as solution-treated condition shows higher creep rupture strength than that of Alloy617. GTAW (Gas Tungsten Arc Welding) trials of tubular specimen using NIMONIC263 filler wire were conducted successfully and the creep ...
2007-07-01
Using Gamma-Ray Burst Prompt Emission to Probe Relativistic Shock Acceleration
It is widely accepted that the prompt transient signal in the 10 keV - 10 GeV band from gamma-ray bursts (GRBs) arises from multiple shocks internal to the ultra-relativistic expansion. The detailed understanding of the dissipation and accompanying acceleration at these shocks is a currently topical subject. This paper explores the relationship between GRB prompt emission spectra and the electron (or ion) acceleration properties at the relativistic shocks that pertain to GRB models. The focus is on the array of possible high-energy power-law indices in accelerated populations, highlighting how spectra above 1 MeV can probe the field obliquity in GRB internal shocks, and the character of hydromagnetic turbulence in their environs. It is emphasized that diffusive shock acceleration theory generates no canonical spectrum at relativistic MHD discontinuities. This diversity is commensurate with the significant range of spectral indices discerned in prompt burst ...
2010-01-01
Use of fuel cells to meet military requirements for mobile power
International Nuclear Information System (INIS)
'Full text:' The use of fuel cell technology in military applications will depend on safe, high energy density systems being developed. An important part of using this technology is also the development of alternative hydrogen producing fuels with high energy densities and are easy to transport. Fuel cells are now a very large R and D effort for several military applications around the world. The major reason is because of the high power demands needed requires electrical energy sources that far exceed the capabilities of batteries currently being fielded for portable applications. Fuel cells are regarded as highly efficient, tactical energy converters that can be adapted for wide range of power requirements. They are potentially the lowest weight power source when coupled with batteries or capacitors to form hybrid systems. Generally electrical power is needed to support a number of applications from ultra-high power for electrical pulses (radios, sensors) to ...
2004-09-25
Ultra high-speed (508 MHz) beam position digital feedback system
Energy Technology Data Exchange (ETDEWEB)
The B-Factory which is constructed by National Laboratory for High Energy Physics is the device for elucidating the breakdown of symmetry of matter and antimatter by studying the behavior of B mesons which are generated in large quantity when the electrons and the positrons which are accelerated to light velocity level are collided. In order to maintain electron beam-positron beam bunch circling the ring at light velocity stably, the instability of the coupled bunch must be overcome. For this purpose, the ultrahigh speed beam position digital feedback control system was developed. This system is composed of the high speed input-output substrate using GaAs LSI, the feedback computation substrate using complementary metal oxide semiconductor and the memory mounted on it, and the real time operation device. The development of both substrates and their functions are explained. The real time data collection and the change of computation parameters for specific bunch in the real time ...
1997-02-01
International Nuclear Information System (INIS)
In this paper, we show that boron transient enhanced diffusion can be reduced to different extents by varying the distribution of nitrogen atoms in the junction. This is attributed to the relative location of nitrogen atoms with respect to boron profile and end-of-range defect band, affecting the interactions between dopants and defects upon annealing. In addition, variations in boron dopant activation and deactivation are also observed. Similar to fluorine co-implantation, it is proposed that nitrogen atoms react with vacancy point defects to form nitrogen-vacancy clusters that will trap the interstitials emitted from end-of-range defects. However, we report that the interstitial sink efficiency of nitrogen atoms is not as good as the co-implanted carbon atoms, which is noticed from the dopant deactivation curves. In terms of extended defect evolution, the results clearly indicate that end-of-range defects can be stabilized by choosing the optimized co-implant condition of N. Finally, ...
2008-12-05
Scientific Electronic Library Online (English)
Abstract in english Frontal weapon is the term used to designate the apparatus consisting of frontal gland and associated structures that participate in the chemical defense of termite soldiers. The ultra structure of the frontal gland and the scanning microscopy of the soldier head was investigated in the termite Amiitermes euamignathus Silvestri, 1901.Campaniform sensilla was not observed but there were 80 to100 sensory bristles around the frontal pore. The glandular epithelium shows only (more) class 1 cells according 10 the classification of NOIROT & QUENNEDEY (1974, 1991). The glandular cells are characterized by apical microvilli, a basal labyrinth and a large quantity of smooth endoplasmic reticulum which forms dense zones throughout the cytoplasm. The secretion is concentrated mainly in the basal pole of the cell and consists of large lipid droplets. The secretory epithelium is covered by a thick apical cuticle composed of a thin outer epicuticle, a ...
2001-06-01
Energy Technology Data Exchange (ETDEWEB)
This paper describes an investigation of electrodeposited Zn-14% Ni and aluminium-based SermeTel 1140/962 coatings as possible replacements for cadmium. Slow strain rate tests were performed to measure the extent of direct hydrogen embrittlement of a high strength steel substrate as a result of the coating process and of hydrogen re-embrittlement caused by coating corrosion. The level of re-embrittlement was shown to depend on both the electrochemical potential of the coating and its barrier properties. Zn-14% Ni coatings caused the most re-embrittlement as they had the most active potential and contained through-thickness defects which left the steel exposed to hydrogen uptake. The microstructure of the high strength steel was also shown to be an important factor affecting the extent of embrittlement. AerMet 100 steel was more resistant than 300M steel and this was attributed to the presence of reverted austenite surrounding the martensite laths in AerMet 100, which trapped absorbed ...
2008-04-15
The cluster structure of the inner crust of neutron stars in the Hartree-Fock-Bogoliubov approach
We analyse how the structure of the inner curst is influenced by the pairing correlations. The inner-crust matter, formed by nuclear clusters immersed in a superfluid neutron gas and ultra-relativistic electrons, is treated in the Wigner-Seitz approximation. The properties of the Wigner-Seitz cells, i.e., their neutron to proton ratio and their radius at a given baryonic density, are obtained from the energy minimization at beta equilibrium. To obtain the binding energy of baryonic matter we perform Skyrme-HFB calculations with zero-range density-dependent pairing forces of various intensities. We find that the Wigner-Seitz cells have much smaller numbers of protons compared to previous calculations. For the dense cells the binding energy of the configurations with small proton numbers do not converge to a well-defined minimum value which precludes the determination of their structure. We show that for these cells there is a significant underestimation of the ...
2011-01-01
The Schenberg spherical antenna: status report
International Nuclear Information System (INIS)
Full text. Here we present a status report of the Schenberg antenna, which started commissioning runs in September 2006 under the full support of FAPESP. In its first commissioning runs we tested three preliminary parametric transducer systems, which did not achieve a high enough performance for placing the antenna sensitivity in the range of the calibrator capacitor. Instead of improving the calibrator, making it capable of introducing a larger input force, we decided to go to a radical upgrading operation: replacing the three transducers for a complete set of six transducers, with better sensitivity and arranged according to the truncated icosahedron configuration, plus two extra ones; starting to install the dilution refrigerator; installing wires, cables, and amplifiers for the complete set of transducer circuits; and a new suspension and vibration isolation system for the cabling and microstrip antennas. We also have been developing a new set of transducers, microwave oscillators, ...
2009-09-14
Several observational studies suggest that solar wind dynamic pressure fluctuations can drive magnetospheric ultra-low frequency (ULF) waves on the dayside. To investigate this causal relationship, we present results from Lyon-Fedder-Mobarry (LFM) global, three-dimensional magnetohydrodynamic (MHD) simulations of the solar wind-magnetosphere interaction. These simulations are driven with synthetic solar wind input conditions, where idealized ULF dynamic pressure fluctuations are embedded in the upstream solar wind. In three of the simulations, a monochromatic, sinusoidal ULF oscillation is introduced into the solar wind dynamic pressure time series. In the fourth simulation, a continuum of ULF fluctuations over the 0-50 mHz frequency band is introduced into the solar wind dynamic pressure time series. In this numerical experiment, the idealized solar wind input conditions allow us to study only the effect of a fluctuating solar wind dynamic pressure, while holding ...
2010-01-01
Simulating fullerene ball bearings of ultra-low friction
Energy Technology Data Exchange (ETDEWEB)
We report the direct molecular dynamics simulations for molecular ball bearings composed of fullerene molecules (C{sub 60} and C{sub 20}) and multi-walled carbon nanotubes. The comparison of friction levels indicates that fullerene ball bearings have extremely low friction (with minimal frictional forces of 5.283 x 10{sup -7} and 6.768 x 10{sup -7} nN/atom for C{sub 60} and C{sub 20} bearings) and energy dissipation (lowest dissipation per cycle of 0.013 and 0.016 meV/atom for C{sub 60} and C{sub 20} bearings). A single fullerene inside the ball bearings exhibits various motion statuses of mixed translation and rotation. The influences of the shaft's distortion on the long-ranged potential energy and normal force are discussed. The phonic dissipation mechanism leads to a non-monotonic function between the friction and the load rate for the molecular bearings.
2007-03-21
Scattered Light from Close-in Extrasolar Planets: Prospects of Detection with the MOST Satellite
The ultra-precise photometric space satellite MOST (Microvariability and Oscillations of STars) will provide the first opportunity to measure the albedos and scattered light curves from known short-period extrasolar planets. Due to the changing phases of an extrasolar planet as it orbits its parent star, the combined light of the planet-star system will vary on the order of tens of micromagnitudes. The amplitude and shape of the resulting light curve is sensitive to the planet's radius and orbital inclination, as well as the composition and size distribution of the scattering particles in the planet's atmosphere. To predict the capabilities of MOST and other planned space missions, we have constructed a series of models of such light curves, improving upon earlier work by incorporating more realistic details such as: limb darkening of the star, intrinsic granulation noise in the star itself, tidal distortion and back-heating, higher angular resolution of the light ...
2003-01-01
Energy Technology Data Exchange (ETDEWEB)
Studies are made on coal in terms of its effective utilization, coal cleaning, fluidization and production of new fuel, and issues globally raised. Coal is abundant in reserves and high in supply stability and economic efficiency. However, it is much in CO2 emission per calorific value. To control as much CO2 emission as possible, effective utilization such as increasing of power generation efficiency has been proceeded with. In addition to ultra supercritical pressure and fluidized bed combustion, cited are coal gasification combined cycle power generation and high temperature type fuel cell. Coal has 5-20% ash and impurities like sulfur/nitrogen. Coal should be used clean by pollution abatement measures such as dust collecting, desulfurization and denitrification. Japan is at a world top level of these technologies. Coal is solid, and therefore, is more difficult to handle than liquid fuel. To use it easily, coal is liquefied into slurry such as COM and CWM, and ...
1994-04-25
Research on deformation characteristic of AZ31Mg alloy and its constitutive equations
Energy Technology Data Exchange (ETDEWEB)
Superplasticity of polycrystalline metallic materials is a phenomenon which shows hundreds to thousands of percents of large plastic deformation without necking in a steady state of low stress, when the uni-axial tensile loading is done in some special thermo-mechanical conditions (some limited ranges of properly high temperature and low strain rate). The main mechanism of superplastic phenomenon is the grain boundary sliding, while the main mechanism of usual plastic deformation is the trans-granular sliding. In this research, the possibility of superplastic deformation in a magnesium alloy (AZ31Mg alloy) was experimentally investigated, because generally speaking, the magnesium alloy whose atomic structure is hexagonal does not have enough formability in a form of trans-granular sliding mechanism. In this paper, the detail of experimental results are shown and discussed. Moreover, the constitutive equations of Mg alloy are proposed on the basis of the experimental results. These ...
2004-07-01
Energy Technology Data Exchange (ETDEWEB)
Concerning the coal liquefaction research under way at the National Institute for Resources and Development, its purpose, contents, achievements, problems, future tasks, etc., are recapitulated. At the meeting, the coal liquefaction research is explained and discussed. Study tours are conducted to a liquefaction plant site, hydrolytic liquefaction facilities, and liquefaction facilities involving ultra-strong acid. Explanations are given on sub-themes of research in and after fiscal 1992 and the future prospects, and discussion is held on general matters. Various views and opinions are expressed by the committee members. Some ask what the chemical structure of coal is and what the model substance that represents coal is. Another insists that basic research on coal structure and reactivity be reconstructed. Those whose goal is to put the technology to practical use express their opinions that a clear position be given the liquefaction technology in the industrial ...
1997-03-01
Reducing the costs of ultrapure water production - a case study
Energy Technology Data Exchange (ETDEWEB)
The 380 MW combined cycle gas turbine power station in Peterborough changed its water supply from town mains to high purity reverse osmosis permeate in October 2000. The high purity water is produced from secondary treated sewage effluent using advanced membrane technology. Alpheus Environmental and British Gas staff have recently completed a study of the power station's demineralization plant to identify the differences in operating costs associated with the change in feedwater. The results show that the ultrapure water produced after the change to a high purity feed is of improved quality and that the demineralization plant regeneration operating costs have been reduced by over 90%. The demineralization plant availability has increased from 78 to 98% enabling almost 20% more ultra pure water to be produced. The change in feedwater has also improved the local environment by significantly reducing the amount of waste chemicals discharged from the site. ...
2002-02-01
Radiations emitted in the decay of /sup 165/Er: A promising medical radionuclide
The 10.3-h /sup 165/Er, decaying by electron capture to stable /sup 165/Ho, offers an excellent promise for use in diagnostic nuclear medicine, especially in conjuction with multiwire proportional-counter cameras. Using an ultra-high-resolution Si(Li) photon spectrometer, L and K x-ray photon yields in /sup 165/Er decay have been measured. The ratio P/sub L//P/sub K/ of electron-capture probabilities in L and K shells is determined to be 0.196 +- 0.030, in good agreement with theory. Estimates of Auger electron yields and yields of very-low-energy electrons from Coster--Kronig transitions are presented. Levels of /sup 169/Er and /sup 171/Er radioactive impurities in the reactor-produced /sup 165/Er sample are experimentally determined. Whole-body dose estimates for /sup 165/Er are given. These compare favorably with /sup 99/Tc dose.
1977-05-01
Radiations emitted in the decay of "1"6"5Er: A promising medical radionuclide
International Nuclear Information System (INIS)
The 10.3-h "1"6"5Er, decaying by electron capture to stable "1"6"5Ho, offers an excellent promise for use in diagnostic nuclear medicine, especially in conjuction with multiwire proportional-counter cameras. Using an ultra-high-resolution Si(Li) photon spectrometer, L and K x-ray photon yields in "1"6"5Er decay have been measured. The ratio P/sub L//P/sub K/ of electron-capture probabilities in L and K shells is determined to be 0.196 +- 0.030, in good agreement with theory. Estimates of Auger electron yields and yields of very-low-energy electrons from Coster--Kronig transitions are presented. Levels of "1"6"9Er and "1"7"1Er radioactive impurities in the reactor-produced "1"6"5Er sample are experimentally determined. Whole-body dose estimates for "1"6"5Er are given. These compare favorably with "9"9Tc dose.
Energy Technology Data Exchange (ETDEWEB)
A new industrial process allowing to reach very high cooling rates in the cooling section after soaking of a continuous annealing line for steel sheets is presented. This process constitutes the successful conclusion of a long term research programme, jointly carried out at CRM and Arcelor Cockerill-Sambre for three years, including laboratory experiments, pilot scale trials and several industrial campaigns. It is running on from developments performed in the framework of the HOWAQ (Hot Water Quench) process. The process successively combines a moderate cooling step (600 deg C/s for 0.8 mm thick strips), in boiling water, and a faster cooling step (above 700 deg C/s), by impinging turbulent cold water in a box. Its main features are simplicity, resulting from advanced developments, soundness, flexibility and cooling homogeneity. As treated steel products are characterized by improved mechanical properties, outstanding surface quality (corrosion resistance) and exceptional flatness. The ...
2003-08-01
Energy Technology Data Exchange (ETDEWEB)
This paper discussed the potential of biofuels with particular reference to the situation in Germany and Europe. Emphasis was on technical potential, such as biofuel production, utilization and environmental aspects. The Institute of Agricultural Technology and Biosystems Engineering ran vTI emission tests on diesel engines to evaluate the environmental impacts of biofuels. This testing facility is able to drive heavy-duty diesel engines in both stationary and dynamic test cycles, such as the European ESC and ETC. Additional analyses were conducted to determine the fine and ultra-fine particles, polycyclic aromatic hydrocarbons (PAH), aldehydes, ketones, and the usual regulated exhaust gas compounds. Ames tests were conducted to assess the mutagenic potential of tailpipe emissions. Previous study results showed that neat vegetable oils can render the exhaust high in mutagenic potency. Some of the non-regulated exhaust gas compounds were found to vary nonlinearly ...
2010-07-01
Optimization of advanced PMOS junctions using Ge, B and F co-implants
International Nuclear Information System (INIS)
The main challenges for PMOS ultra shallow junction formation remain the transient enhanced diffusion (TED) and the solid solubility limit of boron in silicon. It has been demonstrated that low energy boron implantation and spike annealing are key in meeting the 90nm technology node ITRS requirements. To meet the 65nm technology requirements many studies have used fluorine co-implantation with boron and Si"+ or Ge"+ pre-amorphization (PAI) and spike annealing. Although using BF_2"+ can be attractive for its high throughput, self-amorphization and the presence of fluorine, many studies have shown that the fluorine successfully reduce TED, its energy needs to be well optimized with respect to the boron's, therefore BF_2"+ does not present the right fluorine/boron energy ratio for the optimum junction formation. In this work we optimize the fluorine energy for boron energies down to 200eV. We show the dependence of optimized junction on Ge"+ energies of 2keV and ...
2005-08-01
Monitoring power plant fireside corrosion using corrosion probes
Energy Technology Data Exchange (ETDEWEB)
The ability to monitor the corrosion degradation of key components in fossil fuel power plants is of utmost importance for Futuregen and ultra-supercritical power plants. Fireside corrosion occurs in the high temperature sections of energy production facilities due to a number of factors: ash deposition, coal composition, thermal gradients, and low NOx conditions, among others. Problems occur when equipment designed for either oxidizing or reducing conditions is exposed to alternating oxidizing and reducing conditions. This can happen especially near the burners. The use of low NOx burners is becoming more commonplace and can produce reducing environments that accelerate corrosion. One method of addressing corrosion of these surfaces is the use of corrosion probes to monitor when process changes cause corrosive conditions. In such a case, corrosion rate could become a process control variable that directs the operation of a coal combustion or coal gasification ...
2005-01-01
Modeling of the Ostwald ripening of extrinsic defects and transient enhanced diffusion in silicon
Energy Technology Data Exchange (ETDEWEB)
We present an atomistic simulation of the Ostwald ripening of extrinsic defects (clusters, {l_brace}1 1 3{r_brace}s and dislocation loops) which occurs during annealing of ion implanted silicon. The model describes the capture and emission of Si interstitial atoms to and from extrinsic defects of sizes up to thousands of atoms and includes a loss term due to the flux of interstitials to the recombining surface. Key input parameters of the simulation are the variations of the formation energy and of the capture efficiency with the size of the different defects. This model shows that the kinetics of the well-known dissolution of {l_brace}1 1 3{r_brace} defects is only driven by the recombination efficiency at the surface and the distance from the defects to the sample surface. We have subsequently used this model to study defect evolution in low and ultra low energy (ULE) B implanted Si during annealing. Defect dissolution occurs earlier and at smaller sizes in the ...
2002-01-01
Modeling of the Ostwald ripening of extrinsic defects and transient enhanced diffusion in silicon
International Nuclear Information System (INIS)
We present an atomistic simulation of the Ostwald ripening of extrinsic defects (clusters, #left brace#1 1 3#right brace#s and dislocation loops) which occurs during annealing of ion implanted silicon. The model describes the capture and emission of Si interstitial atoms to and from extrinsic defects of sizes up to thousands of atoms and includes a loss term due to the flux of interstitials to the recombining surface. Key input parameters of the simulation are the variations of the formation energy and of the capture efficiency with the size of the different defects. This model shows that the kinetics of the well-known dissolution of #left brace#1 1 3#right brace# defects is only driven by the recombination efficiency at the surface and the distance from the defects to the sample surface. We have subsequently used this model to study defect evolution in low and ultra low energy (ULE) B implanted Si during annealing. Defect dissolution occurs earlier and at smaller ...
2002-01-01
Microstructural evolution of the surface of Mg-Al-based alloy by hydrogen treatment
Energy Technology Data Exchange (ETDEWEB)
The present paper describes the development of ultra-fine grains on the surface of AZ31 alloys caused by hydrogenation and dehydrogenation treatment, so-called HDDR process. Upon hydrogenation process, disproportionation reaction occurred in forming of MgH{sub 2}, Mg{sub 0.42}Al{sub 0.58}, and Al phases. In the following desorption process, the three phases were re-solved into the AZ31 alloy. As a result of the HDDR phenomena, the grain size of AZ31 alloy powders was reduced down to about 100 nm after the heat treatment at 350 C under a hydrogen pressure of 7 MPa for 24 h. The grain size tended to be increased with increasing process temperatures. In addition, the HDDR process was also applied to AZ31 alloy plates. By the HDDR process at 450 C, the grain size was reduced to less than 500 nm, where hydrogenated layer thickness was limited to be in the range of about 20 {mu}m from the surface. The Vickers hardness of AZ31 alloy plates was increased from 51.9 to 59.4 ...
2003-07-01
British Library Electronic Table of Contents (United Kingdom)
Ultra fine tungsten carbide and cobalt powders were milled by high energy planetary ball mill at different ball to powder weight ratios (BPR) to produce particles of WC-10wt%Co hard metal in nanometer scale size. Microstructural characterizations by TEM show that the particle size of tungsten carbide was achieved to 32nm after milling at 15 BPR during 10h. In order to reduce the WC grain growth during the sintering process, tantalum carbide was added to the hard metal as a WC grain growth inhibitor. The nano hard metal powders were compacted at 200MPa pressure and sintered at 1370-1450degreeC temperatures in a high purity hydrogen atmosphere. The results show that the addition of 0.6wt% of TaC improves the hardness and fracture toughness from 1493 HV30 and 11.8MPam (for TaC free sample) to...
2009-01-01
Mechanism of ageing in irradiated polymers
Energy Technology Data Exchange (ETDEWEB)
Samples of ultra-high molecular weight polyethylene (UHMWPE) and nylon 66, of grades suitable for use in medical prostheses, were subjected to irradiation using a /sup 60/Co source. The effects of a 10 Mrad dose on percentage crystallinity, tensile behaviour and dynamic mechanical response were established 3 days after irradiation at intervals over a one year period. Crystallinity in UHMWPE was found to increase progressively during this period with consequent changes in mechanical behaviour. It is proposed that the observed ageing process arises from the breakdown of metastable groups in the polymer, which are formed on irradiation, with consequent release of long inter-lamella tie chains. This removes an inhibition to crystal perfection processes, which can occur at room temperature in polyethylene. Infra-red spectroscopic evidence supports the proposal that the metastable species is peroxy or hydroperoxy and that this decomposes on ageing to a carbonyl group, ...
1988-01-01
Energy Technology Data Exchange (ETDEWEB)
Fe-Ni-Mn martensitic steels are one of the major groups of ultra-high strength steels that have good mechanical properties and ductility in as annealed condition but they suffer from severe inter-granular embitterment after aging. In this paper, the effect of heavy shaped cold rolling and wire drawing on the mechanical properties of Fe-Ni-Mn steel was investigated. This process could provide a large strain deformation in this alloy. The total strain was {epsilon} {approx}7. Aging behavior and tensile properties of Fe-10Ni-7Mn were studied after aging at 753 K. The results showed that the ultimate tensile strength and ductility after cold rolling, wire drawing and aging increased up to 2540 MPa and 7.1 %, respectively, while the conventional steels show a premature fracture stress of 830 MPa with about zero ductility after aging.
2010-07-01
International Nuclear Information System (INIS)
Fe-Ni-Mn martensitic steels are one of the major groups of ultra-high strength steels that have good mechanical properties and ductility in as annealed condition but they suffer from severe inter-granular embitterment after aging. In this paper, the effect of heavy shaped cold rolling and wire drawing on the mechanical properties of Fe-Ni-Mn steel was investigated. This process could provide a large strain deformation in this alloy. The total strain was #epsilon# #approx#7. Aging behavior and tensile properties of Fe-10Ni-7Mn were studied after aging at 753 K. The results showed that the ultimate tensile strength and ductility after cold rolling, wire drawing and aging increased up to 2540 MPa and 7.1 %, respectively, while the conventional steels show a premature fracture stress of 830 MPa with about zero ductility after aging.
2010-07-01
Lyman-alpha emitters as tracers of the transitioning Universe
Of the many ways of detecting high redshift galaxies, the selection of objects due to their redshifted Ly-alpha emission has become one of the most successful. But what types of galaxies are selected in this way? Until recently, Ly-alpha emitters were understood to be small star-forming galaxies, possible building-blocks of larger galaxies. But with increased number of observations of Ly-alpha emitters at lower redshifts, a new picture emerges. Ly-alpha emitters display strong evolution in their properties from higher to lower redshift. It has previously been shown that the fraction of ultra-luminous infrared galaxies (ULIRGs) among the Ly-alpha emitters increases dramatically between redshift three and two. Here, the fraction of AGN among the LAEs is shown to follow a similar evolutionary path. We argue that Ly-alpha emitters are not a homogeneous class of objects, and that the objects selected with this method reflect the general star forming and active galaxy ...
2011-01-01
Laser stabilization at 1536 nm using regenerative spectral hole burning
International Nuclear Information System (INIS)
Laser frequency stabilization giving a 500-Hz Allan deviation for a 2-ms integration time with drift reduced to 7 kHz/min over several minutes was achieved at 1536 nm in the optical communication band. A continuously regenerated spectral hole in the inhomogeneously broadened "4I_1_5_/_2(1)#->#"4I_1_3_/_2(1) optical absorption of an Er"3"+:Y_2SiO_5 crystal was used as the short-term frequency reference, while a variation on the locking technique allowed simultaneous use of the inhomogeneously broadened absorption line as a long-term reference. The reported frequency stability was achieved without vibration isolation. Spectral hole burning frequency stabilization provides ideal laser sources for high-resolution spectroscopy, real-time optical signal processing, and a range of applications requiring ultra-narrow-band light sources or coherent detection; the time scale for stability and the compatibility with spectral hole burning devices make this technique ...
2001-04-15
Improving T D reliability. How pumped storage can boost network security
Energy Technology Data Exchange (ETDEWEB)
The key to improving transmission-network security is faster response to contingencies. Now a new breed of pumped-storage plant - designed for ultra-fast response - may soon provide a tool dispatchers can use to improve network security. This type of plant can also substantially increase the effective capacity of existing transmission lines and improve the performance of thermal generating units. The Mt. Hope Waterpower Project, planned for Rockaway Township, NJ, 35 miles west of New York City, lies strategically adjacent to major load centers at the eastern end of the PJM control area and near the interconnection point with the New York Power Pool (NYPP). This location also is in an area deficient in significant generating facilities. Maximum design capacity of the project is 2000 MW, provided by six reversible pump/turbines, each with a nominal 340-MW rating. The upper reservoir, with a surface area of only 60 acres, provides 5000 acre-ft of active storage volume ...
1994-03-01
The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in- place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional and multi-component seismic area is being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended- reach jetting lance and other ultra-short radius lateral technologies. Improved completion efficiency, additional wells at closer spacings better estimates of oil-in-place will result in additional oil production by primary and enhanced recovery processes. Technical progress is described for field ...
1996-07-01
Implantation damage and anomalous diffusion of implanted boron in silicon through SiO_2 films
International Nuclear Information System (INIS)
Boron is implanted in crystalline silicon through oxide layers with different thicknesses. The implantation is carried out at various doses and energies of interest in ultra large scale integration (ULSI) application. Rapid thermal annealings (RTA) are used to obtain shallow junctions and electrical activation of the B atoms. However, transient enhanced diffusion induced by implantation damage can be observed. The boron concentration profiles before and after annealing are obtained with secondary ion mass spectrometry (SIMS). It is found that the diffusion transient in the tail region of the boron profile increases with decreasing oxide thickness. Even more, if the implantation damage concerns mostly the oxide, i.e. when the concentration peak is located in this oxide, the oxygen knocked into the silicon substrate could play this way an important role in restricting the boron diffusion, which is good to obtain very shallow junctions. On the other hand, for thinner ...
Implantation damage and anomalous diffusion of implanted boron in silicon through SiO[sub 2] films
Energy Technology Data Exchange (ETDEWEB)
Boron is implanted in crystalline silicon through oxide layers with different thicknesses. The implantation is carried out at various doses and energies of interest in ultra large scale integration (ULSI) application. Rapid thermal annealings (RTA) are used to obtain shallow junctions and electrical activation of the B atoms. However, transient enhanced diffusion induced by implantation damage can be observed. The boron concentration profiles before and after annealing are obtained with secondary ion mass spectrometry (SIMS). It is found that the diffusion transient in the tail region of the boron profile increases with decreasing oxide thickness. Even more, if the implantation damage concerns mostly the oxide, i.e. when the concentration peak is located in this oxide, the oxygen knocked into the silicon substrate could play this way an important role in restricting the boron diffusion, which is good to obtain very shallow junctions. On the other hand, for thinner ...
1993-07-16
Hybrid electric vehicles and electrochemical storage systems - a technology push-pull couple
Energy Technology Data Exchange (ETDEWEB)
In the advance of fuel cell electric vehicles (EV), hybrid electric vehicles (HEV) can contribute to reduced emissions and energy consumption of personal cars as a short term solution. Trade-offs reveal better emission control for series hybrid vehicles, while parallel hybrid vehicles with different drive trains may significantly reduce fuel consumption as well. At present, costs and marketing considerations favor parallel hybrid vehicles making use of small, high power batteries. With ultra high power density cells in development, exceeding 1 kW/kg, high power batteries can be provided by adapting a technology closely related to consumer cell production. Energy consumption and emissions may benefit from regenerative braking and smoothing of the internal combustion engine (ICE) response as well, with limited additional battery weight. High power supercapacitors may assist the achievement of this goal. Problems to be solved in practice comprise battery management to ...
1999-12-01
High-performance hybrid pervaporation membranes with superior hydrothermal and acid stability
Energy Technology Data Exchange (ETDEWEB)
A new organic-inorganic hybrid membrane has been prepared with exceptional performance in dewatering applications. The only precursor used in the sol-gel synthesis of the selective layer was organically linked 1,2-bis(triethoxysilyl)ethane (BTESE). The microporous structure of this layer enables selective molecular sieving of small molecules from larger ones. In the dehydration of n-butanol with 5% of water, the membrane shows a high separation factor of over 4000 and ultra-fast water transport at a rate of more than 20 kg m{sup -2} h{sup -1} at 150C. This can be related to the high adsorption capacity of the material and the sub-micron thickness of the selective layer. The selectivity has now remained constant over almost one and a half years under continuous process testing conditions. Apart from the hydrothermal stability, the membrane exhibits a high tolerance for acid contamination. A slow performance decline in flux and separation factor is only observed at a ...
2009-05-15
High temperature aluminum electrolytic capacitors for ULEV inverters
Energy Technology Data Exchange (ETDEWEB)
A comparison between the concepts of the hybrid electric vehicle (HEV) and the ultra low emission vehicle (ULEV) was presented. The ULEV uses a much larger engine compared to the HEV, but it uses a lower Kw generator/motor and inverter/charger to use the latest engine and battery technology. The underlying goal of the ULEV is to supply auxiliary power under start-up and heavy load conditions and to remove indirect systems such as steering, starting and blower control from the engine via small electric drives. The challenge is to build a ULEV that is robust enough to withstand any environmental conditions. Since the ULEV engine is larger, it can experience compartment temperatures greater than 125 degrees C, which limits the use of conventional filter capacitors. Nippon Chemi-Con has recently developed U787D, the world's first continuous 150 degrees C rated aluminum electrolytic capacitor designed to meet the ambient, ripple currents and vibration ...
2000-07-01
High performance ultra-steels with recyclable design
Energy Technology Data Exchange (ETDEWEB)
The global production of steel is predicted to increase rapidly to meet future demands. In order to conserve the natural resources, certain measures must be taken. These include perfecting the recycling of steel, improving the performance to extend the life of the material, and reduce the need for massive production of steel by increasing the strength of the material. This paper presented a design concept for ultrafine complex microstructure steel. The National Research Institute for Metals in Japan has worked on a project which investigated 800 MPa ferrite steel for welded structures with a chemical composition similar to 400 MPa-class plain carbon steel. The doubled strength was attributed to grain refinement. Novel welding techniques were also used for joining the ultrafine microstructure. In this study, low carbon Si-Mn ferrite-pearlite steels were subjected to a thermo-mechanical treatment to produce a microstructure of 1 micron order ultrafine grain ferrite plus finely dispersed ...
2000-07-01
Hard, infrared black coating with very low outgassing
Energy Technology Data Exchange (ETDEWEB)
Infrared astronomical instruments require absorptive coatings on internal surfaces to trap scattered and stray photons. This is typically accomplished with any one of a number of black paints. Although inexpensive and simple to apply, paint has several disadvantages. Painted surfaces can be fragile, prone to shedding particles, and difficult to clean. Most importantly, the vacuum performance is poor. Recently a plasma enhanced chemical vapor deposition (PECVD) process was developed to apply thick (30 {micro}m) diamond-like carbon (DLC) based protective coatings to the interior of oil pipelines. These DLC coatings show much promise as an infrared black for an ultra high vacuum environment. The coatings are very robust with excellent cryogenic adhesion. Their total infrared reflectivity of < 10% at normal incidence approaches that of black paints. We measured outgas rates of <10{sup -12} Torr liter/sec cm{sup 2}, comparable to bare stainless steel.
2008-06-02
Future limits on isotropic Lorentz violation in the photon sector from UHECRs and TeV gamma rays
Present and future ultra-high-energy-cosmic-ray facilities (e.g., the Pierre Auger Observatory with South and North components) and TeV-gamma-ray telescope arrays (e.g., HESS/VERITAS and CTA) have the potential to set stringent indirect bounds on the nine Lorentz-violating parameters of nonbirefringent modified Maxwell theory minimally coupled to standard Dirac theory. Theoretically, the most interesting case is isotropic Lorentz violation, which is described by a single parameter [taken to vanish for the case of the standard Lorentz-invariant theory]. It appears possible to obtain in the future an upper (lower) indirect bound on this single isotropic Lorentz-violating parameter at the +10^{-21} (-10^{-17}) level. Comparison is made with existing and future direct bounds from laboratory experiments. The possible physics implications of upper bounds at the 10^{-21} level are also briefly discussed.
2011-01-01
Friction properties of WS{sub 2}/graphite fluoride thin films grown by pulsed laser deposition
Energy Technology Data Exchange (ETDEWEB)
Graphite fluoride (CF{sub x}) is investigated as an additive for WS{sub 2} thin films to reduce its sensitivity to moisture. The films are grown onto hardened 440C stainless steel disks by pulsed laser deposition using the 248 nm line from an excimer laser. Substrate temperature and additive concentration are varied to control film chemistry and crystal structure. The effect of relative humidity (i.e., < 1 to 85% RH) on friction is evaluated. Coatings grown at RT from targets with a low concentration of CF{sub x} exhibit ultra-low friction (ULF) behavior in dry air (i.e., {mu} {<=} 0.01), but friction increases with RH. Mechanisms for the ULF behavior are proposed which suggest that further reductions in friction are possible. Films grown at 300 C or with higher concentrations of CF{sub x} are relatively insensitive to humidity, but have more typical friction coefficients ({mu} {<=} 0.04) in dry air. (orig.)
1995-12-01
Free-Electron Lasers: Present Status and Future Prospects
Energy Technology Data Exchange (ETDEWEB)
Free-electron lasers as scientific instruments are reviewed. The present status and future prospects are delineated with attention drawn to the size, complexity, availability, and performance capability of this new tool. The Free-Electron Laser (FEL) was proposed by John Madey in 1970 (1), although earlier work, relevant to the concept, had been performed by Motz (2) and by Phillips (3). Experimental demonstration was achieved by Madey, et. al. in 1975 and 1976 (4). Since that time, FELs of diverse configurations have been operated at several laboratories around the world. At present, FEL development is focused in two directions: in constructing reliable FELs for scientific research and in extending FEL capability to vacuum ultra-violet (VUV) and even shorter wavelengths. In this article we shall only very briefly review the principles of an FEL, putting emphasis on those aspects that limit performance, after which we shall discuss the applications, present status ...
1990-05-01
Focused ion beam techniques for fabricating geometrically-complex components and devices.
Energy Technology Data Exchange (ETDEWEB)
We have researched several new focused ion beam (FIB) micro-fabrication techniques that offer control of feature shape and the ability to accurately define features onto nonplanar substrates. These FIB-based processes are considered useful for prototyping, reverse engineering, and small-lot manufacturing. Ion beam-based techniques have been developed for defining features in miniature, nonplanar substrates. We demonstrate helices in cylindrical substrates having diameters from 100 {micro}m to 3 mm. Ion beam lathe processes sputter-define 10-{micro}m wide features in cylindrical substrates and tubes. For larger substrates, we combine focused ion beam milling with ultra-precision lathe turning techniques to accurately define 25-100 {micro}m features over many meters of path length. In several cases, we combine the feature defining capability of focused ion beam bombardment with additive techniques such as evaporation, sputter deposition and electroplating in order to ...
2004-03-01
First plasma experiment on spherical tokamak device UTST
International Nuclear Information System (INIS)
The UTST (University of Tokyo Spherical Tokamak) device was constructed for the purpose of exploring the formation of ultra-high beta ST (Spherical Tokamak) plasma using the double null plasma merging method. When two plasmas merge together to form a single plasma, magnetic field lines reconnect, and the magnetic field energy is converted to the plasma kinetic energy, increasing the plasma beta. The merging start-up has been demonstrated in the TS-3/4, START and MAST devices using coils inside the vacuum vessel and TS-3 plasma obtained 50% beta. In order to demonstrate the start-up in a more reactor relevant situation, UTST has all poloidal field coils outside the vacuum vessel. The first plasma experiment on the UTST was performed from December, 2007. In the result, the plasma obtained 10 kA by using only outer PF coils and single ST was generated at the lower area (z=-0.3 - -1.0[m]) close to a washer gun. This result suggests that another washer gun on the top of ...
2009-04-01
International Nuclear Information System (INIS)
We present an approach for fabrication of intentionally positioned epitaxial InAs QDs in a micron sized light emitting diode. For site-selective growth, a combination of molecular beam epitaxy (MBE) and focused ion beam (FIB) implantation technology in an all-ultra-high-vacuum (UHV) setup has been employed. Single dot occupancy of almost 55 % on FIB patterned nano-depressions was successfully achieved. Thereafter, carrier injection and subsequent radiative recombination from the positioned InAs/GaAs self-assembled QDs was investigated by embedding these QDs in the intrinsic part of a GaAs-based micron sized p-i-n junction device. Few or single dot are expected to be electrically addressed in these devices. We report results from electroluminescence (EL) measurement which proves the single dot characteristics of our device. The EL spectra consist of sharp emission lines and their dependence on injection current shows linear behavior for exciton and quadratic ...
2010-03-21
Energy-filtered electron microscopy for imaging core-shell nanostructures
Energy Technology Data Exchange (ETDEWEB)
CuAg core-shell nanoparticles are synthesized by ultra-high vacuum thermal evaporation. We show on this system how the Energy-Filtered Transmission Electron Microscopy (EFTEM) technique allows one to improve the characterization by precisely pointing out the formation of core-shell arrangements in bimetallic nanoparticle assemblies. A criterion to measure the shell thickness from EFTEM images on unique core-shell nanoparticles is defined, that can be used for core-shell nanoparticles of any sizes, with shell thicknesses over 1 nm. It is based on the intensity variation along a line drawn across a core-shell nanoparticle on a EFTEM image. This criterion has been validated by a close comparison of the shell thickness measurements performed in this work and the ones obtained by acoustic micro-Raman spectroscopy. Using this criterion, we report a strong correlation between the size of the Cu cores and the formation of the core-shell arrangements in the nanoparticle ...
2008-08-15
Energy Technology Data Exchange (ETDEWEB)
In this study, the exhaust gas from a common-rail direct injection diesel engine was investigated both upstream and downstream warm-up catalytic converters (WCC). Three different types of ultra-low sulfur fuels (ethanol-diesel blend, ethanol-diesel blend with cetane improver and pure diesel) were tested in this study. The objective of the work was to study the engine performance and the formation of THC (total hydro carbon), CO (carbon monoxide), NO{sub x} (nitrogen oxides), smoke and PM (particulate matters) when using these fuels. THC and CO emissions of the ethanol-diesel blend fuels were slightly increased, and about 50-80% mean conversion efficiencies of THC and CO on catalysts were achieved in the ECE R49 13-mode cycle. Smoke was decreased by more than 42% in the entire ECE 13-mode cycles. From the measurement of scanning mobility particle sizer (SMPS) for the particle size range of 10-385 nm, the total number and total mass of the PM of the ethanol-diesel ...
2008-10-15
Cooperative Research Centre for Mining Technology and Equipment (CMTE) annual report 1998/99
Energy Technology Data Exchange (ETDEWEB)
The Centre's new structure, implemented in July 1997 is now operating well. CMTE Development Limited is now the legal entity for the CRC and replaces the previously unincorporated joint venture. CMTE has ten core participating organisations. Roche Highwall Mining Pty. Ltd., withdrew participation during the year. The annual report describes its structure and management and various cooperative links. It outlines research programs in the following areas: mining; geological sensing; automation; reliability and maintenance; and coal processing. Projects include: developing an ultra-short-radius drilling machine for drainage of methane gas from coal seams; developing techniques for improved drilling speed and accuracy to reduce costs for gas drainage holes in underground coal mining; developing draglines; developing geophysical logging tools; developing autonomous control of underground vehicles such as coal-haul-dump (LHD) and haulage trucks, developing tools ...
1999-07-01
Energy Technology Data Exchange (ETDEWEB)
Most of the organic electronic devices are nowadays fabricated under poor vacuum conditions. In this regard, there is only little knowledge about the impact of contamination of the metal electrode on the charge injection barrier in this kind of electronic devices. In our study we have performed X-ray and ultra violet photoemission spectroscopy (XPS, UPS) on interfaces between the organic semiconductor -sexithiophene and sputter cleaned (ideal) metals as well as contaminated (realistic) metals. As metal substrates we have used silver, gold, palladium, and platinum. These metals provide us a wide range of metal work functions from 4.2 eV for silver up to 5.5 eV for platinum. For all interfaces of -sexithiophene and contaminated metals we have observed a reduction of the interface dipole and the hole injection barrier. The charge injection barrier in all four cases is almost independent of the underlying metal (within an error of 0.2 eV) and the interface dipole ...
2007-07-01
Coherent transport of matter waves in disordered optical potentials
Energy Technology Data Exchange (ETDEWEB)
The development of modern techniques for the cooling and the manipulation of atoms in recent years, and the possibility to create Bose-Einstein condensates and degenerate Fermi gases and to load them into regular optical lattices or disordered optical potentials, has evoked new interest for the disorder-induced localization of ultra-cold atoms. This work studies the transport properties of matter waves in disordered optical potentials, which are also known as speckle potentials. The effect of correlated disorder on localization is first studied numerically in the framework of the Anderson model. The relevant transport parameters in the configuration average over many different realizations of the speckle potential are then determined analytically, using self-consistent diagrammatic perturbation techniques. This allows to make predictions for a possible experimental observation of coherent transport phenomena for cold atoms in speckle potentials. Of particular ...
2007-07-01
Co-precipitated ZnAl2O4 spinel precursor as potential sintering aid for pure alumina system
British Library Electronic Table of Contents (United Kingdom)
Ultra-fine ZnAl2O4 spinel hydrogel precursor synthesized from mixed salt solutions of Zn^2^+ and Al^3^+ ions using ammonium hydroxide-hexamethylenetetramine as basic media for co-precipitation was used as bonding material and sintering aid for pure alumina system. The hydrogel powder exhibited some well-defined ZnAl2O4 spinel phases at 800^oC. Alumina compacts were fabricated by incorporating small proportions of the precursor in alumina powder and firing at different temperatures (1350-1500^oC). The degree of densification was studied by measurement of fired shrinkage, apparent porosity, bulk density and cold crushing strength. Phase compositions and microstructural features of sintered samples were evaluated by XRD and SEM respectively. Addition of 0.2% hydrogel powder to alumina exhibit...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
Tar sand bitumen is petroleum-based ultra-heavy oil, and has a great amount of reserve like coal. However, there are still a lot of problems for its highly effective utilization. This paper discusses whether the light components in bitumen show independent behavior during the thermal cracking of heavy components, or not. Solvent effect and reaction mechanism during the thermal cracking are also derived from the change of their chemical structures. Athabasca tar sand bitumen was separated into light and heavy fractions by vacuum distillation based on D-1660 of ASTM. Mixtures of the both fractions at various ratios were used as samples. Negative effect of the light fraction on cracking of the heavy fraction was observed with dealkylation and paraffin formation Polymerization of the dealkylated light fraction to the heavy fraction was suggested due to lack of hydrogen in the thermal cracking under nitrogen atmosphere, which resulted in the formation of polymer. 3 ...
1996-10-28
Energy Technology Data Exchange (ETDEWEB)
Wastewater from a food-manufacturing plant with a low concentration of organic matter was treated at 37 centigrade in an anaerobic fluidized-bed reactor or in an upflow anaerobic sludge blanket. As the influent TOC (total organic carbon) concentration decreased, the TOC removal efficiency in these reactors decreased from 85% to 65%. The concentration of suspended solids in the effluent could be reduced to 20 mg/l, which corresponded to 7% of that in the influent. The effluent from both reactors was treated aerobically in a fixed-bed reactor. The TOC concentration and optical density of effluent from the aerobic treatment were reduced to 5 mg/l and 0.005, respectively. When the effluent treated anaerobically or aerobically was passed over an activated carbon column, the effluent TOC concentration was reduced to 2 to 3 mg/l. The conductivity in raw wastewater was remarkably reduced on an ion-exchange resin column. Ultra-pure water for industrial use was obtained by ...
1994-03-25
Advanced Neutron Source: Plant Design Requirements. Revision 4
Energy Technology Data Exchange (ETDEWEB)
The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and ...
1990-07-01
Energy Technology Data Exchange (ETDEWEB)
Negative ion electrospray ionization (ESI) coupled with high field Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) allows for the direct detection of acidic NSO compounds in petroleum. The technique requires no chromatographic separation, is able to distinguish 18 different compound classes (e.g., neutral nitrogen, carboxylic acids and oxygenates), and can identify {approx}14,000 distinct masses by ultra-high mass resolution and mass accuracy. We previously studied three crude oils from different geological origins [Organic Geochemistry 33 (2002b) 743-759]. Here, we expand our research by comparing two source-equivalent Smackover oils of different levels of thermal maturity. We observe clear differences in the distribution of NSO compound classes, types (number of rings plus double bonds within a class), and number of alkyl carbons. With increasing thermal stress, the relative amount of sulfur and oxygen containing compounds decreases, ...
2004-07-01
A search for electron cyclotron maser emission from compact binaries
Unipolar induction (UI) is a fundamental physical process, which occurs when a conducting body transverses a magnetic field. It has been suggested that UI is operating in RX J0806+15 and RX J1914+24, which are believed to be ultra-compact binaries with orbital periods of 5.4 min and 9.6 min respectively. The UI model predicts that those two sources may be electron cyclotron maser sources at radio wavelengths. Other systems in which UI has been predicted to occur are short period extra-solar terrestrial planets with conducting cores. If UI is present, circularly polarised radio emission is predicted to be emitted. We have searched for this predicted radio emission from short period binaries using the VLA and ATCA. In one epoch we find evidence for a radio source, coincident in position with the optical position of RX J0806+15. Although we cannot completely exclude that this is a chance alignment between the position of RX J0806+15 and an artifact in the data ...
2007-01-01
Energy Technology Data Exchange (ETDEWEB)
It is an object of the claimed invention to combine chemical treatment with microfiltration process to treat groundwater, leachate from contaminated soil washing, surface and run-off waters contaminated with toxic metals, radionuclides and trace amounts of organics from variety of sources. The process can also be used to treat effluents from industrial processes such as discharges associated with smelting, mining and refining operations. Influent contaminants amenable to treatment are from a few mg/L to hundreds of mg/L. By selecting appropriate precipitation, ion exchange and adsorption agents and conditions, efficiencies greater than 99.9 percent can be achieved for removal of contaminants. The filtered water for discharge can be targeted with either an order of magnitude greater or lower than contaminant levels for drinking water.
1992-12-31
Spectrograph for free-electron laser experiments
International Nuclear Information System (INIS)
The design and construction of a Browne-Buechner type round pole face magnetic electron spectrograph is described. The design is based on the first order transfer properties of the bending magnet including the focal surface, dispersion, magnification and resolution. Second order aberrations are compared wit numerical ray tracing results using measured field data to simulate the magnet. The numerical results are also compared with floating wire measurements on the system. Agreement is within one part in 10"4. Data extraction from the instrument is done with an array of copper detectors placed along the focal surface. The spectrograph has been successfully employed in free-electron laser (FEL) experiments for over a year.
1983-03-21
Energy Technology Data Exchange (ETDEWEB)
Multi-kilo-electron-volt x-ray microscopy will be an important laser-produced plasma diagnostic at future megajoule facilities such as the National Ignition Facility (NIF). However, laser energies and plasma characteristics imply that x-ray microscopy will be more challenging at NIF than at existing facilities. We use analytical estimates and numerical ray tracing to investigate several instrumentation options in detail, and we conclude that near-normal-incidence single spherical or toroidal crystals may offer the best general solution for high-energy x-ray microscopy at NIF and similar large facilities. Apertured Kirkpatrick{endash}Baez microscopes using multilayer mirrors may also be good options, particularly for applications requiring one-dimensional imaging over narrow fields of view. {copyright} 1998 Optical Society of America
1998-04-01
Fabrication and characterization of low aberration micrometer-sized electron lenses
British Library Electronic Table of Contents (United Kingdom)
Intrinsic spherical aberrations of electron lenses have been the major resolution limiting factor in electron microscopes for several decades. While effective correctors have recently been implemented, an alternative to correct these aberrations is to circumvent them by scaling down lens dimensions by several orders of magnitude. We have fabricated electrostatic lenses exhibiting one micrometer diameter apertures and evaluated their beam forming properties against predictions from numerical ray tracing simulations. It turns out that it is routinely possible to shape a paraxial low-energy electron beam by such micron-sized lenses. Beam profiles have been measured both at a distant detector as well as in a plane close to the lens. It is shown that the lens can form a parallel beam extending ...
2010-01-01
Epigenetic regulation of autosomal gene expression by sex chromosomes
British Library Electronic Table of Contents (United Kingdom)
Males and females display differences in physiology, behaviour and susceptibility to many diseases. Genome-wide transcription profiling studies have uncovered large-scale sex differences in autosomal gene expression in somatic tissues that are thought to underlie such 'sexual dimorphisms'. Because males and females differ genetically mainly in their sex chromosome complement, most sex differences can be traced back to the X and Y chromosomes. Although sex hormones are usually considered the main architects of sexual dimorphisms, recent studies have demonstrated that sex chromosomes can also induce sex differences in somatic gene expression in the absence of hormonal differences. The recent discovery of epigenetic sex differences that are not hormone-induced brings us closer to understandin...
2011-01-01
International Nuclear Information System (INIS)
The dithiocarbamate and thiuram compounds, including disulfiram, were compared for their efficacies in influencing tissue distribution of a trace dose of intravenously injected lead plus "2"0"3Pb in rats. The tested compounds were sodium diethyldithiocarbamate (DEDTC), sodium dimethyldithiocarbamate (DMDTC), tetraethylthiuram disulfide (disulfiram), a complex of zinc and manganese ethylenebisdithiocarbamate (mancozeb), manganese ethylenebisdithiocarbamate (maneb), sodium monomethyldithiocarbamate (metham), zinc propylene bisdithiocarbamate (propineb), tetramethylthiuram disulfide (thiram), zinc ethylenebisdithiocarbamate (zineb), and zinc dimethyldithiocarbamate (ziram). The results of this study show that interactions can occur between lead and DEDTC, DMDTC, disulfiram, metham, thiram, and ziram, resulting in increased levels of lead in brain and probably potentiation of the neurotoxic effects of lead.
Compact Single-Stage Fuel Processor for PEM Fuel Cells. Final report
Energy Technology Data Exchange (ETDEWEB)
Based on observations during the steam reforming of ethanol, the authors conclude that carbon was forming in the steam generator due to the thermal decomposition of ethanol. Since ethanol is being thermally decomposed, they were operating the steam generator at too high of a temperature. The thermal degradation of ethanol was confirmed by using a GC with a flame ionization detector. They observed trace amounts of additional hydrocarbons other than methane in the effluent which we assume maybe ethane and ethylene. We identified the operating conditions that allowed us to steam reform ethanol for an acceptable amount of time. These conditions were a steam temperature of 200 C and a wall temperature of 400 C at the center of the reactor. The calculated ratios of CO{sub 2}/CO indicate that we can lower the potential for carbon deposition from the Boudouard further by reducing the pressure.
2000-01-01
Charles Darwin and the Evolution of Human Grammatical Systems
British Library Electronic Table of Contents (United Kingdom)
Charles Darwin's evolutionary theories of animal communication were deeply embedded in a centuries-old model of association psychology, whose prodromes have most often been traced to the writings of Aristotle. His notions of frequency of occurrence of pairings have been passed down through the centuries and were a major ontological feature in the formation of associative connectivity. He focused on the associations of cause and effect, contiguity of sequential occurrence, and similarity among items. Cause and effect were often reduced to another type of contiguity relation, so that Aristotle is most often evoked as the originator of the associative bondings through similarity and contiguity, contiguity being the most powerful and frequent means of association. Contiguity eventually became ...
2010-01-01
Application of radiolead to metabolic studies
International Nuclear Information System (INIS)
A review is presented of the literature through 1977 on the uses of radioactive lead isotopes in metabolic studies in man, animals, and plants. These studies have been done mainly with the naturally-occurring, long-lived (22-yr half life) "2"1"0Pb, but a few were with 53-hr "2"0"3Pb or 10.6-hr "2"1"2Pb. Such studies have made possible estimates of the metabolic parameters of lead in man and animals, such as intestinal absorption, the ratio of fecal-to-urinary excretion of endogenous lead, residence time of lead in the body and in various organs, and the distribution in the body (skeleton, liver, kidney, and blood). Subsequently, these parameters and data have been used to trace the sources of lead for man, such as those from the atmosphere, food, cigarette smoke, and automobile exhaust.
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