Energy Technology Data Exchange (ETDEWEB)

One of the aims in the safety assessment of SFR-1 is to estimate the release to the environment. In order to make these calculations there is a need to describe the inventory in greater detail. The new computerised database of waste in SFR-1 gives a good possibility to achieve this. The aim for project SAFE is to make both conservative and realistic radionuclide transport calculations. To achieve this goal there must be two inventories. The conservative inventory is the inventory used in the design of the repository, which in most parts is identical with the limits in the licence for SFR-1. There is a great interest to have good estimates of the volumes of the different waste types. A thorough prognosis should be made in 1999, but until then the latest one from 1995 could be used in the calculations. The total (actual) inventory of nuclides is calculated from the measurements of the ...

International Nuclear Information System (INIS)

Nuclear fuel vendors in Japan are now studying reprocessed uranium (RepU) fuel in order to prepare for full scale utilization in the future. Separate studies are made for PWR and BWR fuel. The study consists of 2 phrases. The purposes of phase-1 are to understand various RepU characteristics in the fuel fabrication process, to analyze the core characteristics by loading RepU assemblies, to solve the problems clarified in the study, and to collect basic data for licensing. In phase-2, the effects of impurities on the fabrication process will be evaluated, and the safety of RepU fuel manufacturing will be confirmed with a RepU fuel fabrication campaign in 1990. The neutronic data will be collected after insertion into power reactors, and the data will be used to verify plant safety for full utilization of RepU in the future. This paper summarizes the phase-1 study results. 1. RepU Characteristics. The internal and external radiation exposures due to nuclide ...

Energy Technology Data Exchange (ETDEWEB)

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

Energy Technology Data Exchange (ETDEWEB)

The masses of proton rich nuclides in the vicinity of N=Z=43 were measured with the Penning trap mass spectrometer SHIPTRAP at GSI. These nuclei were produced in the fusion-evaporation reaction {sup 36}Ar+{sup 54}Fe at energies of 5.0 and 5.9 MeV/u and separated at the velocity filter SHIP. The data are of astrophysical interest since these nuclei are believed to be a part of the rp and {nu}p process paths. The masses of {sup 85}Mo and {sup 87}Tc were measured for the first time. The masses of another two nuclides, {sup 86,87}Mo, were determined for the first time in a direct mass measurement. For these nuclides the mass excess deviates from values of the 2003 Atomic Mass Evaluation by up to 1.5 MeV, indicating a systematic shift of the mass surface in this region of the nuclear chart. Additionally, the masses of {sup 86}Zr and {sup 85}Nb were measured and found to be in agreement with the values obtained at JYFLTRAP. The ...

International Nuclear Information System (INIS)

In the framework of the development of burnup calculation method for commercial fast reactors, a sensitivity analysis was carried out to clarify the dependence of fuel burnup characteristics on nuclear data libraries (NDLs). The following NDLs were compared: JEF-2.2, ENDF/B-VI Release 5, JENDL-3.2 and JENDL-3.3. The NDL-dependence of material balance for main heavy metal nuclides ("2"3"5U, "2"3"8U, "2"3"9Pu, "2"4"0Pu and "2"4"1Pu) was small, since the number densities at the end of one-cycle burnup did not change over 1 or 2% among the above-mentioned libraries. Relatively large differences were found for minor actinide nuclides, especially for "2"3"6U, "2"3"7Np, "2"4"2"mAm, "2"4"3Am and curium isotopes. The number densities for these nuclides after burning up showed remarkable NDL-dependence over 5% through 50%. A burnup sensitivity analysis system based on the generalized perturbation theory enabled ...

Energy Technology Data Exchange (ETDEWEB)

The use of chemically selective laser ionization combined with {beta} -delayed neutron counting at CERN/ISOLDE has permitted identification and half-life measurements for 623-ms {sup 61}Mn up through 14-ms {sup 69}Mn . The measured half-lives are found to be significantly longer near N=40 than the values calculated with a quasiparticle random-phase-approximation shell model. Gamma-ray singles and coincidence spectroscopy has been performed for {sup 64,66}Mn decays to levels of {sup 64,66}Fe , revealing a significant drop in the energy of the first 2{sup +} state in these nuclides that suggests an unanticipated increase in collectivity near N=40 . {copyright} {ital 1999} {ital The American Physical Society }

Energy Technology Data Exchange (ETDEWEB)

The evaluated nuclear data given in JENDL-3.2 were compared with other evaluated data sets and available experimental data, for important minor actinides of {sup 242m}Am and {sup 243}Am, and fission product nuclides of {sup 99}Tc and {sup 140}Ce. Since problems were found as a result of the comparison, the data of JENDL-3.2 were improved for these nuclides. It was found that the evaluated data of Maslov et al. were superior to the others. They were adopted for {sup 242m}Am and {sup 243}Am after further improvements. For {sup 99}Tc and {sup 140}Ce, resonance parameters and optical model parameters were improved. The cross sections of these two nuclides in the smooth part were re-calculated. The present results were given in the neutron energy range from 10{sup -5} eV to 20 MeV in the ENDF-6 format, and adopted to JENDL-3.3. (author)

Energy Technology Data Exchange (ETDEWEB)

The masses of the proton-rich nuclides {sup 85,86,87}Mo and {sup 87}Tc have been measured with the Penning trap mass spectrometer SHIPTRAP at GSI. The measured mass excesses of these nuclei deviate from the values of the Atomic Mass Evaluation 2003 by up to 1.6 MeV, indicating a systematic shift of the mass surface in this region compared to previous measurements. A local mass extrapolation based on the new results has been made for the mass range A=80-95. Measured and extrapolated mass values and the derived separation energies have been compared to theoretical mass models. Taking into account the new mass excess values, rp-process network calculations have been performed. Preliminary results show changes in the final abundances for A=86-92 by up to a factor of 30. Results of measurements and calculations are presented, and the issue of a potential Zr-Nb cycle is addressed.

International Nuclear Information System (INIS)

The feasibility of immobilizing simulated radioactive slurry (SRS) by alkali-activated slag---clay minerals composite cement (AASCM) was studied under the experimental conditions. The results show that the dosage of SRS and water cement ratio (W/C) have significant effect on the flowability of the mixture of AASCM and SRS. The more dosage of SRS, the lower flowability. When cement/sand ratio is 1: 1 and W/C is 0.45, the flowability of the mixture meets the case of solidification engineering and the compressive strength of the waste forms containing 20% SRS meets the needs of GB 14569.1-93. The setting time of the mixture of AASCM and SRS is highly dependent on temperature while sorts of anions have little influence on it. The application of AASCM is suitable below 20 degree C. The leaching resistance of AASCM based waste forms is superior to that of OPC based waste forms. The control of the forms to Sr2+ is stronger than that to Cs+. Silicon fume can improve ...

International Nuclear Information System (INIS)

A new two-body interaction recently derived for nuclei in the 0f1p shell by fitting two-body matrix elements to 494 energy levels in A=41-66 nuclei, is used to investigate the neutron-rich nuclei in the vicinity of the doubly closed nuclide "4"8Ca. This study is of fundamental interest in providing a test for the new effective interaction away from the stability line. Masses and binding energies are calculated for a variety of neutron-rich nuclei and compared with experimental data, where available. In addition level schemes for "5"0"-"5"2Ca, "5"1"-"5"2Sc and "5"1"-"5"2Ti have been calculated and are compared with available experimental data. In general a good correspondence between theory and experiment is found, but some systematic discrepancies are apparent. ((orig.)).

Energy Technology Data Exchange (ETDEWEB)

Data and functions of the cell burnup calculation of the SRAC system were revised to improve mainly the accuracy of the burnup calculation of high conversion light water reactors (HCLWRs). New burnup chain models were developed in order to treat fission products (FPs) and actinide nuclides in detail. Group cross section library, SRACLIB-JENDL2, was generated based on JENDL-2 nuclear data file. In generating this library, emphasis was placed on FPs and actinides. Also revised were the data such as the average energy release per fission for various actinides. These improved data were verified by performing the burnup analysis of PWR spent fuels. Some new functions were added to the SRAC system for the convenience to yield macroscopic cross sections used in the core burnup process. (author).

International Nuclear Information System (INIS)

Tarapur Atomic Power Station Unit-4 is first 540 MWe pressurized heavy water reactor in India. It achieved criticality on 06th March 2005 and then operated at full power i.e 500 MWe. Radiation workers during the normal operation and reactor shutdown are exposed to radiation field. The control of dose rates and the collective dose of the radiation workers is most important for the best performance of the reactor. Experience gained during the operation of the 220 MWe reactors has shown that the Moderator system, primary heat transport system, annulus gas system and moderator cover gas system are the main systems contributing to the dose rate and collective dose. In order to identify the radio nuclides contributing to the radiation field, study was undertaken at TAPS Unit-4. Various samples from the Moderator, primary heat transport system, annulus gas system and moderator cover gas system were collected and analysed for the spectrometric analysis. This paper ...

Science.gov (United States)

We briefly reviewed and summarized the experimental study on {beta}-delayed proton decays published by our group over the last 8 years, namely the experimental observation of {beta}-delayed proton decays of nine new nuclides in the rare-earth region near the proton drip line and five nuclides in the mass 90 region with N{approx}Z by utilizing the p-{gamma} coincidence technique in combination with a He-jet tape transport system. In addition, important technical details of the experiments were provided. The experimental results were compared to the theoretical predictions of some nuclear models, resulting in the following conclusions. (1) The experimental half-lives for {sup 85}Mo, {sup 92}Rh, as well as the predicted 'waiting point' nuclei {sup 89}Ru and {sup 93}Pd were 5-10 times longer than the macroscopic-microscopic model predictions of Moeller et al. [At. Data Nucl. Data Tables 66,131(1997)]. These data considerably ...

Energy Technology Data Exchange (ETDEWEB)

Nuclear Act of Korea requires the manifest of low and intermediate level radioactive waste generated from nuclear power plants and other nuclear facilities prior to deliver to a disposal sites. Individual history records of the radioactive waste should be described the information about the activity of nuclides in the drum, total activity, weight, the type of waste. So a fully automated nuclide analysis assay system(non-destructive) of a radwaste drum was developed. For the nuclides that could not be analysed directly by MCA, the activities of the representative {gamma}-emitters(Cs-137, Co-60) contained in the drum were measured by using that system. Then the scaling factors were used to calculate the activities of {alpha} - and {beta}-emitters. This assay system divided a drum into 8 segments, a segment into 8 sectors to minimize analysis error, and used several methods(transmission ratio, differential ...

KoreaScience (Korea)

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International Nuclear Information System (INIS)

Analytical expression of the dependence of freezing temperature of electrolyte (CdCl_2, CdSO_4, BeSO_4) aqueous solutions on their composition was found. Three different methods were suggested were suggested for calculation of water activity in multicomponent solution. It was established that sublinear extrapolation of freezing temperature of salt aqueous solutions was possible not up to -5 deg C, but up to -15 deg C, independently of their composition. 6 refs.; 2 figs.

International Nuclear Information System (INIS)

Black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electrons from a linear accelerator to a dose of 100 kGy and radioactivity was measured in order to estimate induced radioactivity in the irradiated foods. Induced radioactivity could not be detected significantly by #gamma#-ray spectrometry in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list of photonuclear reactions which could produce radioactivity below 10 MeV. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H_5_0 according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from "4"0K contained in the samples. (author).

International Nuclear Information System (INIS)

In the radiochemical reprocessing of spent fuel from nuclear reactors, a considerable amount of liquid, solid, and gaseous waste is formed; this waste is potentially dangerous to humans and requires the development of special and complex technological techniques for its localization and reliable long-term storage. The most hazardous are liquid wastes of high specific activity - water-tailings solutions obtained in the first cycle of extraction after the removal of uranium and plutonium. These solutions contain more than 99.9% of all the other transuranic elements - isotopes of neptunium, americium, and curium. Where necessary, some fission products and actinides may be removed from wastes of high specific activity for subsequent use. The quantity, composition, and activity of these wastes varies within broad limits, depending on the type and power of the reactor, the initial nuclide composition of the fuel, and its specific ...

Energy Technology Data Exchange (ETDEWEB)

In the context of safety assessment of radioactive waste repositories, complex radionuclide transport models covering key safety-relevant processes play a major role. In recent Swiss safety assessments, such as Kristallin-I, an important drawback was the limitation in geosphere modelling capability to account for geosphere heterogeneities. In marked contrast to this limitation in modelling capabilities, great effort has been put into investigating the heterogeneity of the geosphere as it impacts on hydrology. Structural geological methods have been used to look at the geometry of the flow paths on a small scale and the diffusion and sorption properties of different rock materials have been investigated. This huge amount of information could however be only partially applied in geosphere transport modelling. To make use of these investigations the 'PICNIC project' was established as a joint cooperation of PSI/Nagra and QuantiSci to provide a new geosphere transport ...

Energy Technology Data Exchange (ETDEWEB)

The effect of the coated composite surface of particles on the mechanical properties of the powder bed was investigated. Polyethylene-silica surface composite powder was prepared at several coating ratios with Hybridizer. Various tests on mechanical properties of the powder bed were carried out with the prepared powder, and the following results were obtained: The ultimate tensile strength depends only on the cohesive force between particles, and the contact probability model of composite particles led to good agreement between the experimental and calculated values. The coefficient of internal friction and cohesive shear strength were influenced due to the interlocking effect of the surface roughness of composite particles. The effects of coating particles became small with dynamic properties like angle of repose. It is possible to control the mechanical properties in a step wise ...

Energy Technology Data Exchange (ETDEWEB)

The procedure was developed to enable STUK (Radiation and Nuclear Safety Authority) to make simplified estimates on off-site consequences based on the existing results of the PSA level 2 calculations done by e.g. power utilities. Method is based on dose calculated from each nuclide group of reactor activity inventory when the same release fraction for each group is assumed. This means that a specific new result from PSA level 2 can be categorised to find out a representative PSA level 3 result for this case. In addition a user interface including the procedure was prepared. Secondly some new insights about consequences based on the releases from PSA level 2 is expected to give better understanding of risks at prevailing increased reactor power levels. In this case only some early health effects and long-term doses were estimated without full-scope PSA level 3 approach. (orig.)

International Nuclear Information System (INIS)

There is an increasing interest in using radioisotopes of rare earth elements for internal radiotherapy and for imaging in nuclear medicine. "1"7"7Lu is one of the promising radionuclides. This article reports on the first measurements of the excitation function for the production of "1"7"7Lu with proton-beam energies up to 17 MeV on natural hafnium targets. The experimental cross sections for the reaction "n"a"tHf(p,x)"1"7"7Lu were obtained by the activation of a stacked-foil target and subsequent gamma spectrometry. Theoretical cross sections were calculated up to 35 MeV with the EMPIRE nuclear reaction model code. The measured and calculated cross sections were used for deriving the thick-target yields and for estimating the production of other nuclides than "1"7"7Lu. Measured production cross sections of "1"7"5","1"7"6","1"7"7","1"7"8Ta on the same target are also presented.

Energy Technology Data Exchange (ETDEWEB)

In nuclear fuel with a burn-up of 33 kg/t U and 52 kg/t U 15 transuranium nuclides /sup 237/Np to /sup 246/Cm have been determined by alpha and gamma spectroscopy after radiochemical separation.

CERN Document Server

We demonstrate that a massive asymptotic giant branch (AGB) star is a good candidate as the main source of short-lived radionuclides in the early solar system. Recent identification of massive (4-8 solar masses) AGB stars in the Galaxy, which are both lithium- and rubidium-rich, demonstrates that these stars experience proton captures at the base of the convective envelope (hot bottom burning), together with high-neutron density nucleosynthesis with 22Ne as a neutron source in the He shell and efficient dredge-up of the processed material. A model of a 6.5 solar masses star of solar metallicity can simultaneously match the abundances of 26Al, 41Ca, 60Fe, and 107Pd inferred to have been present in the solar nebula by using a dilution factor of 1 part of AGB material per 300 parts of original solar nebula material, and taking into account a time interval between injection of the short-lived nuclides and consolidation of the first meteorites equal to 0.53 Myr. Such a ...

International Nuclear Information System (INIS)

Some aspects of metrological provision of X-ray radiometric analyzers for mineral raw composition and gamma-gamma-logging equipment are considered. Standard samples (SS) based on the phenol-formaldehyde resin with the introduced quantities calculated of element compositions in the form of oxides and salts are described. Principles of metrological provision developed are used when carrying out state acceptance tests of X-ray radiometric analyzer RAL-M-102 ''Ehkran'' and gamma-gamma-logging equipmnt RSK-102. Economic benefit from introduction of an SS set is #approx# 60-100 thousand roubles per year.

Energy Technology Data Exchange (ETDEWEB)

Analysis of the coke gas combustion porcess is presented. Standard kinetic relationships were utilized. Calculations were performed for coke gas with high and low content of H/sub 2/ and for blasting air 20 and 100/sup 0/C. Temperature relationships, composition of gas combustion products and release of nitrogen oxides were determined. Results are analyzed which will make it possible to control the composition of combustion products.

International Nuclear Information System (INIS)

The distribution of radiation dose commitments within the body that can result from the lung deposition of a number of transuranic radionuclides ("2"3"7Pu, "2"3"8Pu, "2"3"9Pu, "2"4"0Pu, "2"4"1Pu, "2"4"2Pu, "2"4"3Pu, "2"4"4Pu, "2"4"1Am, "2"4"2Am, "2"4"3Am, "2"4"4Am, "2"4"2Cm, "2"4"3Cm, "2"4"4Cm, and "2"4"6Cm) was calculated. The variables that influence these organ dose commitments include the mobility of the particle or its dissolution products within the body, the radiation characteristics of the inhaled radionuclides and their progeny, and the size of the particles inhaled. In the calculation of organ dose commitments for whole-body, lungs, liver, bone tissues, kidneys, and gastrointestinal tract from the inhalation of transuranium radionuclides, physical characteristics of importance are the dimensions of the particle, its aerodynamic properties, and its density. For particles within the respirable size range, a useful description is ...

International Nuclear Information System (INIS)

Measurements of gamma-ray spectra, following the thermal neutron fission of "2"3"5U have been made using a high purity germanium detector at the University of Massachusetts Lowell (UML) Van de Graaff facility. The gamma spectra were measured at delay times ranging from 0.2 s to nearly 10000 s following the rapid transfer of the fission fragments with a helium-jet system. On the basis of the known gamma transitions, forty isotopes have been identified and studied. By measuring the relative intensities of these transitions, the relative yields of the various precursor nuclides have been calculated. The results are compared with the recommended values listed in the ENDF/B-VI fission product data base (for the lifetimes and the relative yields) and those published in the Nuclear Data Sheets (for the beta branching ratios). This information is particularly useful for the cases of short-lived fission products with lifetimes of the order of fractions ...

International Nuclear Information System (INIS)

Service water, 100 l each, was collected at an intake of a water treatment plant and at a tap after water was left running for five minutes. The carriers of strontium and cesium were added to water immediately after sampling, and the sample was vigorously stirred and filtered. Then it was passed through a cation exchange column at a rate of 80 ml/min. Strontium and cesium were eluted with hydrochloric acid from the cation exchange column, and separated. After the radiochemical separation, the mounted precipitates were counted for activity using low background beta counters normally for 60 min. Net sample counting rates were corrected for counter efficiency, recovery, self absorption and decay to obtain the content of strontium-90 and cesium-137 radioactivity per sample aliquot. From the results, concentrations of these nuclides in the original sample were calculated. The maximum values obtained were 0.29 pCi/l of Sr-90 in Kyoto in August, 1981, ...

International Nuclear Information System (INIS)

First structural wall material (FSW) materials in inertial fusion energy (IFE) power reactors will be irradiated under typical repetition rates of 1-10 Hz, for an operation time as long as the total reactor lifetime. The main objective of the present work is to determine whether a continuous-pulsed (CP) approach can be an efficient method in modeling the pulsed activation process for operating conditions of FSW materials. The accuracy and practicability of this method was investigated both analytically and (for reaction/decay chains of two and three nuclides) by computational simulation. It was found that CP modeling is an accurate and practical method for calculating the neutron-activation of FSW materials. Its use is recommended instead of the equivalent steady-state method or the exact pulsed modeling. Moreover, the applicability of this method to components of an IFE power plant subject to repetition rates lower than those of the FSW is ...

Energy Technology Data Exchange (ETDEWEB)

The characterization data obtained to date are described for Approved Testing Material (ATM)-103, which is spent fuel from Assembly D101 of pressurized-water reactor Calvert Cliffs, No. 1. This report is one in a series being written by the Materials Characterization Center (MCC) at Pacific Northwest Laboratory (PNL) on spent fuel ATMs. The ATMs are receiving extensive examinations to provide a source of well-characterized spent fuel for testing in the US nuclear waste repository program. ATM-103 consists of 176 full-length irradiated fuel rods with rod-average burnups of about 2600 GJ/kgM (30 MWd/kgM) and less than 1% fission gas release. Characterization data include 1) as-fabricated fuel design, irradiation history, and subsequent storage and handling; 2) isotopic gamma scans; 3) fission gas analyses; 4) ceramography of the fuel and metallography of the cladding; 5) special fuels studies involving analytical transmission electron microscopy (AEM); 6) calculated ...

Energy Technology Data Exchange (ETDEWEB)

The characterization data obtained to data are described for Approved Testing Material 105 (ATM-105), which is spent fuel from Bundles CZ346 and CZ348 of the Cooper Nuclear Power Plant, a boiling-water reactor. This report is one in a series being prepared by the Materials Characterization Center at Pacific Northwest Laboratory (PNL) on spent fuel ATMs. The ATMs are receiving extensive examinations to provide a source of well-characterized spent fuel for testing in the US Department of Energy Office of Civilian Radioactive Waste Management (OCRWM) Program. ATM-105 consists of 88 full-length irradiated fuel rods with rod-average burnups of about 2400 GJ/kgM (28 MWd/kgM) and expected fission gas release of about 1%. Characterization data include (1) descriptions of as-fabricated fuel design, irradiation history, and subsequent storage and handling; (2) isotopic gamma scans; (3) fission gas analyses; (4) ceramography of the fuel and metallography of the cladding; (5) special fuel studies ...

Energy Technology Data Exchange (ETDEWEB)

Coal ash is a substance that has been mixed into minerals in the earth`s crust during their coalification process. Estimation was made on what kinds of mineral composition have been mixed into coals. Noted first was the kinds of compounds contained in the ash, wherein the ratios of mass in the compounds and minerals were correlated, and selection was made on minerals which are thought correlated. The selection criterion was based on minerals containing silica, alumina, iron oxide, lime and magnesium as compounds. Then, a phase equilibrium line diagram was used to estimate compositions and melting points of minerals which are thought to have been produced from these compounds. By comparing the estimation with the measured melting points of the ashes, mineral compositions thought reasonable were all selected. Assumption was possible on minerals that are thought to have been transferred into coal ash. Compound indications of ...

International Nuclear Information System (INIS)

The composition of sputter-deposited HgS films was determined by electron microprobe analysis. From the relative x-ray intensity as a function of film thickness, the depth of the ionizations that produce SK sub(#alpha#) and HgM sub(#alpha#) was found to be approximately 0.65 #mu#m at an accelerating voltage of 15 kV. This value agreed well with a value calculated from Castaings' empirical law after absorption correction. The determination of film composition was limited to sufficiently thicker films than this critical value, usually 1 - 2 #mu#m thick. The relation between the conposition of bulk standard determined by chemical analysis and the x-ray intensity ratio was used for the correction of film composition. The results showed that the crystal structure of HgS films was independent of the composition, i.e., the growth of metastable #betta#-HgS films was not caused by the ...

International Nuclear Information System (INIS)

Radiation-initiated polymerization of styrene and acrylic acid in poplar wood were investigated for the preparation of wood-polymer composites. The direct irradiation method was applied to the monomer adsorbed poplar wood specimens. 8000 Ci "6"0Co source at a dose rate of about 0.4 Mrad/h was used. Furthermore the effects of carbon tetrachloride, methanol, dioxane and acrylonitrile on styrene polymerization were investigated and the reaction rates were calculated for each case. The influence of CCl_4 (10%) on acrylic acid polymerization in poplar wood was also determined. (author).

Energy Technology Data Exchange (ETDEWEB)

A prediction of delayed neutron yields for actinides which are important in the nuclear energy field is given. The prediction is based on a correlation related to a suggested cluster structure of the nucleus. (author).

Energy Technology Data Exchange (ETDEWEB)

Of some interest is the comparison between the actinide nuclide burning up (fission) rates such as americium 241, americium 242, curium 244, and neptunium 237, in the reactors with fast or thermal neutron spectra.

Energy Technology Data Exchange (ETDEWEB)

The paper studied a possibility of estimating characteristics of coal liquefaction residue from liquefaction conditions in the case of fixing coal kind in the NEDOL process coal liquefaction PSU. Wyoming coal was used for the study, and the already proposed simplified liquefaction reaction models were used. Among material balances explained by the models, those of asphaltene, preasphaltene, THF insoluble matters are concerned with residue composition. Ash content is separately calculated from ash balance. Reaction velocity constants of simplified liquefaction reaction models which influence the residue composition were obtained by the multiple regression method from experimental results in the past. The estimation expression of residue viscosity was introduced from residue ash/composition. When the residue composition is estimated by the model from liquefaction conditions, and the ...

International Nuclear Information System (INIS)

The results of theoretical and experimental investigations, describing the effect of ionizing radiation on wood and its main components and methods for production of wood-plastic composites by means of radiation-induced chemical modification are generalized. Domestic and foreign experience in their production is systematized; physico-mechanical characteristics of new material, simulation and calculation of irradiating devices, as well as calculation and experimental study of #gamma#-radiation attenuation both by wood material and by wood of different species are given. Gamma sources ("6"0Co isotope, a hot loop of a nuclear reactor) as well as electron accelerators are considered as ionizing radiation sources.

International Nuclear Information System (INIS)

Prompt fission neutron energy spectra for "2"3"5U and "2"3"9Pu have been measured for fission neutron energies greater than the energy of the incident neutrons inducing fission. The measurements were undertaken to investigate the shape dependence of the fission neutron spectra upon both the incident neutron energy and the mass of the nucleus undergoing fission. Measurements were made for both nuclides at incident neutron energies of 0.50, 1.50, 2.50 and 3.50 MeV. The data are presented either as relative yields or as ratios of measured spectra to that of "2"3"5U at 0.50 MeV. Incident neutrons were produced by the "7Li(p,n)"7Be reaction using a pulsed, bunched proton beam from the 5.5 MV Van de Graaff accelerator at the University of Massachusetts Lowell Radiation Laboratory. Fission neutrons were detected by a thin liquid scintillator with good time resolution capabilities. Neutron energies were determined by time-of-flight techniques with pulse-shape ...

International Nuclear Information System (INIS)

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

International Nuclear Information System (INIS)

The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects are calculated, with reference to ITER/NET (International Thermonuclear Experiment Reactor/Next European ...

Science.gov (United States)

In response to a need of the safeguards community, we have begun an evaluation effort to upgrade the recommended values of the prompt neutron emission multiplicity distribution, P/sub nu/ and its average value, nubar. This paper will report on progress achieved thus far. The evaluation of the uranium, plutonium, americium and curium nuclide's nubar values will be presented. The recommended values will be given and discussed. 61 references.

Energy Technology Data Exchange (ETDEWEB)

This paper continues, with respect to the transplutonium nuclides, earlier efforts to collate and evaluate data from the scientific literature on the prompt neutron multiplicity distribution from fission and its first moment = ..sigma..nuPnu. The isotopes considered here for which P/sub nu/ and or data (or both) were found in the literature are of americium (Am), curium (Cm), berkelium (Bk), californium (Cf), einsteinium (Es), fermium (Fm), and nobelium (No).

Energy Technology Data Exchange (ETDEWEB)

In the groundwater flow modelling part of this work the effective dilution volume in the well scenario was estimated by means of transient simulations of groundwater flow and transport, which are coupled due to the varying salinity. Both deep, drilled wells and shallow surface wells in the vicinity of the repository were considered. The simulations covered the time period from the present to 1000 years after the present. Conceptually the fractured bedrock consists of planar fracture zones (with a high fracture density and a greater ability to conduct water) and the intact rock (in which the fracture density and the hydraulic conductivity are low). For them the equivalent-continuum model was applied separately. Thus, the fractured bedrock was considered as piecewise homogeneous (except for the depth dependence) and isotropic continuum with representative average characteristics. A generic simulation model for groundwater flow and solute transport was developed on the basis of ...

Energy Technology Data Exchange (ETDEWEB)

The complex formation of zirconium with biphenyl mono- and biscatecholyazo derivatives has been studied spectrophotometrically. The composition of the complexes, form and charge of complex-forming zirconium ions have been established. A procedure is suggested for calculation of molar absorptivities and stability constants for each of the complexes formed simultaneously in the system. Possible complex formation schemes have been studied. The data obtained were used to develop a spectrophotometric method of determining zirconium in the presence of large amounts of copper.

Energy Technology Data Exchange (ETDEWEB)

A model has been developed to predict the chemical composition of lakes that form in pyrite-bearing open-pit mines. Pyrite oxidation in wall rock releases sulfuric acid and metals, which mix with ground waters in the lake. Aqueous metal concentrations are calculated using MINTEQA2.

Energy Technology Data Exchange (ETDEWEB)

The equilibrium composition and temperature resulting from the combustion of hydrocarbon fuels in combination with hydrogen have been analytically evaluated. Rich, lean and stoichiometric mixtures have been considered for this purpose. The flame temperature data obtained from computer calculations has been fitted with an equation expressed in terms of calorific value, C/H ratio, air-fuel ratio and heat of dissociation of the fuel mixture. This equation can be used to calculate the flame temperature directly without resorting to the elaborate calculation of species concentration. The results obtained using the equation have been found to have an accuracy of 0.05 to 2.5% for different fuel combinations. (author).

Energy Technology Data Exchange (ETDEWEB)

Micro-Vickers hardness measurement has been used to determine the composition of functionally graded materials (FGMs). Materials used in the present study are Al-SiC, Al-Shirasu and Al-Al{sub 3}Ni FGMs, which are fabricated by a centrifugal method. The micro-hardness of the aluminum matrix for Al-SiC FGM markedly increases as the volume fraction of SiC particles increases. However, the tendency is not so clear in the cases of Al-Shirasu and Al-Al{sub 3}Ni FGMs. Plastic strain energy due to thermal misfits between the matrix and dipersed particles is calculated based on an elasto-plastic analysis by applying a shell theory after Lee et al. The hardness is correlated theoretically with the composition gradient through the mean plastic strain energy (responsible for dislocation density). It is concluded that the composition gradient of metal-based FGMs can be determined from micro-hardness measurements. ...

International Nuclear Information System (INIS)

A method has been developed for calibration of CT-numbers to volumetric electron density distributions using tissue substitutes of known elemental composition and experimentally determined electron density. This information have been used in a dose calculation method based on photon and electron interaction processes. The method utilizes a convolution integral between the photon fluence matrix and dose distribution kernels. Inhomogeneous media are accounted for using the theorems of Fano and O'Connor for scaling dose distribution kernels in proportion to electron density. For clinical application of a calculated dose plan, a method for prediction of accelerator output have been developed. The methods gives the number of monitor units that has to be given to obtain a certain absorbed dose to a point inside an irregular, inhomogeneous object. The method for verification of dose distributions outlined in this study makes it ...

Energy Technology Data Exchange (ETDEWEB)

Sorption studies of cesium, strontium, and cobalt (Cs, Sr, and Co) on bentonite under various experimental conditions, such as contact time, pH, sorbent and sorbate concentration, and temperature, have been performed. The sorption data for all these metals have been interpreted in terms of Freundlich, Langmuir, and Dubinin-Radushkevich equations. Thermodynamics parameters, such as heat of sorption {Delta}H{degrees}, free energy change {Delta}G{degrees}, and entropy change {Delta}S{degrees}, for the sorption of these metals on bentonite have been calculated. The value of {Delta}H{degrees} shows that the sorption of Cs was exothermic, while the sorption of Sr and Co on bentonite were endothermic in nature. The value of {Delta}G{degrees} for their sorption was negative, showing the spontaneity of the process. The maximum loading capacity of Cs, Sr, and Co were 75.5, 22, and 27.5 meq, respectively, for 100 g of bentonite. The mean free energy E of Cs, Sr, and Co ...

British Library Electronic Table of Contents (United Kingdom)

The analysis of complex fluids such as crude oils, fuels, vegetable oils and mixed waste streams poses significant challenges arising primarily from the multiplicity of components, the different properties of the components (polarity, polarizability, etc.) and matrix properties. We have recently introduced an analytical strategy that simplifies many of these analyses, and provides the added potential of linking compositional information with physical property information. This aspect can be used to facilitate equation of state development for the complex fluids. In addition to chemical characterization, the approach provides the ability to calculate thermodynamic properties for such complex heterogeneous streams. The technique is based on the advanced distillation curve (ADC) metrology, wh...

International Nuclear Information System (INIS)

Plutonium, seized from illicit trafficking in nuclear materials, can originate from several, distinct sources. The primary focus of nuclear-forensics investigations of confiscated Pu is to specify correctly its origin. Such specification is possible by means of accurate determination the Pu isotopic composition. Five Pu samples of different origins were analysed by thermal-ionisation mass spectrometry. The source (i.e., the type of production reactor) of each sample was determined by comparing the measured Pu isotopic composition with that calculated by one of two reactor-production computer codes, ORIGEN2 and SCALE. These results, in conjunction with the age determination of each sample, allow us to deduce the origin of each. (author)

International Nuclear Information System (INIS)

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

International Nuclear Information System (INIS)

The decay of mass-separated samples of the previously unknown nuclide "7"1Br have been investigated by means of the Chalk River on-line isotope separator. Eleven #gamma#-transitions were assigned to the decay of this nuclide and its half-life was measured to be 21.4 +- 0.6 s. A simple decay scheme for "7"1Br has been constructed incorporating six levels in its daughter, "7"1Se. The half-life of the first excited state in "7"1Se was measured to be 5.5 +- 1.0 #mu#s and the transition from this state to the ground state was found to be highly converted. Systematic trends in the level schemes of "6"7Zn, "6"9Ge and "7"1Se are investigated. (orig.).

International Nuclear Information System (INIS)

We studied the influence of alloying on the structural and electronic properties of the unrelaxed and relaxed Si_1_-_yC_y random alloys by means of ab initio theoretical calculations using two methods: (i) a supercell approach in connection with the plane-wave pseudopotential method; (ii) the full-potential augmented plane-wave plus local orbitals (APW+lo) method. The first method is used to obtain the relaxed atomic structure. The relaxed atomic positions obtained by pseudopotential calculations were used to calculate the band structure via the second method. The local density approximation was used for the exchange and correlation energy density functional. We investigated the lattice parameters and band gap energies. We found that a quite smaller gap appears in the neighborhood of y=0.03125 concentration of C atoms. The band gap shows a large anomalous bowing and is strongly composition dependent. ...

Energy Technology Data Exchange (ETDEWEB)

Experimental results of nuclear reaction and radiative decay for A = 203 nuclides are evaluated. Adopted properties for all the nine isobars, Au, Hg, Tl, Pb, Bi, Po, At, Rn, Fr of mass 203 are presented. Nothing is yet known for [sup 203]Os. 96 refs.

International Nuclear Information System (INIS)

In the execution of disposal of low and intermediate level radioactive wastes, it is important to evaluate accurately the kind and quantity of each radionuclide in the wastes. For such an evaluation, correlation of non-gamma-emitting nuclides based on gamma-emitting nuclides is recommended and regarded as a partial method. This method necessitates a completion of a highly accurate and reliable nondestructive assay system of gamma-emitting nuclides for partical use. In 1992, in support of the new waste disposal program in Hungary, Paks NPP initiated a waste characterization program to determine the radiological properties of its rad wastes. A segmented gamma scanning system has been set up to measure the gamma-emitting nuclides in 2000 litre low level drums following in-drum compaction. In the framework of the program a radiochemical analysis sub-program was stated to determine the long-lived non-gamma ...

Energy Technology Data Exchange (ETDEWEB)

Sensors installed at a telephone office building in Neenah, WI, continuously monitor 24 parameters related to the operation of the building's heating, ventilating, and air conditioning (HVAC) system. This data is stored in a dedicated minicomputer and can be retrieved, in various formats, for subsequent analyses. For more than a year, we have measured indoor and outdoor concentrations of both fine and coarse airborne particles, their chemical constituents, and volatile organic compounds at this same location. Using this data, we have examined the composition of the indoor air as it correlates to the composition of the outdoor air and the various HVAC operating parameters. The steady-state indoor concentrations of the particles, particulate constituents, and organic vapors can be explained in the context of a mass balance model. This model can also be used to calculate the rate at which selected chemicals are ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Questions: How important is the choice of flow routing algorithm with respect to application of topographic wetness index (TWI) in vegetation ecology? Which flow routing algorithms are preferable for application in vegetation ecology? Location: Forests in three different regions of the Czech Republic. Methods: We used vegetation data from 521 georeferenced plots, recently sampled in a wide range of forest communities. From a digital elevation model, we calculated 11 variations of TWI for each plot with 11 different flow routing algorithms. We evaluated the performance of differently calculated TWI by (1) Spearman rank correlation with average Ellenberg indicator values for soil moisture, (2) Mantel correlation coefficient between dissimilarities of species composition and dissimil...

Energy Technology Data Exchange (ETDEWEB)

The paper presents a procedure for the calculation of an absorption-refrigeration plant that uses an LiBr/ZnBr{sub 2}/CH{sub 3}OH solution and is driven throughout the year by heat received from a solar pond. The calculations for the solar pond are based on a finite-difference solution of the transient heat conduction differential equation during the year, and the operation of the refrigeration unit is simulated by the use of functions describing the thermodynamic behaviour of the working medium. On the basis of the procedure devised, correlations and nomographs are developed that describe the seasonally optimum operation of the proposed composite system. The nomographs may be employed for a first estimation in the design of such systems. (Author).

International Nuclear Information System (INIS)

Thienyl oxazoles and thienyl isoxazoles, are composite molecules having two subsystems thiophene and oxazole molecules connected together by a single bond that they have 13 isomers. They are potential candidates for many kinds of applications such as OLED and nonlinear optical materials. Initially equilibrium geometries of title compounds have been obtained without any restriction using density functional theory with 6-311++g(2d,p) basis set. We obtained structural parameters, dipole moment and electronic energy. At the second stage, we have calculated some electronic and nonlinear optical properties such as HOMO and LUMO energies, polarizability, anisotropic polarizability and hyper polarizability using same level of theory.

Science.gov (United States)

The total half-life and the half-life for spontaneous fission are evaluated for the various long-lived nuclides of interest. Recommended values are presented for /sup 241/Am, /sup 242m/Am, /sup 243/Am, /sup 242/Cm, /sup 243/Cm, /sup 244/Cm, /sup 245/Cm, /sup 246/Cm, /sup 247/Cm, /sup 248/Cm, and /sup 250/Cm. The uncertainties are provided at the 95% confidence limit for each of the recommended values.

Energy Technology Data Exchange (ETDEWEB)

Measurements of the half-lives of some long-lived nuclides of elements Z = 92, 94, 95 and 96 have been compiled and evaluated. Recommended values are presented for {sup 232-236,238}U, for {sup 236,238-242,244}Pu, for {sup 241,242m,243}Am, and for {sup 242-248,250}Cm. Values are presented for both spontaneous fission half-life and total half-life. Problems with reported uncertainties are also discussed. (author).

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 unknown origin are ...

Energy Technology Data Exchange (ETDEWEB)

A centralized, automatic monitoring system for coal mines has been developed. The system consists of newly-developed and improved sensors, transmission equipment, a minicomputer designed for scientific and technical calculations, and accompanying software (MOLES). MOLES performs six functions: input, computation, decision, memory, output and correction. Previously, centralized monitoring has been limited to single dimensional monitoring of the 'time and point' type. The present system carries out data analysis and processing with respect to time, space and item. It is also capable of simple automatic diagnosis of abnormalities. (In Japanese)

International Nuclear Information System (INIS)

The stability constant values of Pa(V) with some complexing ligands (chloride, sulfate and oxalate) are graphically determined using solvent extraction data. The organic phase was at constant composition of HTTA in benzene while the aqueous phase was held at constant hydrogen ion concentration and ionic strength of 3. The curve-fitting method was adopted throughout this investigation, giving the following values. The stability constants obtained are used to calculate the distribution of the different Pa (V) species in the corresponding aqueous phase (expressed in mole fraction) as a function of ligand ion concentration.

International Nuclear Information System (INIS)

The energy spectra of energetic confined alpha particles are being measured using the pellet charge exchange method [R. K. Fisher, J. S. Leffler, A. M. Howald, and P. B. Parks, Fusion Technol. 13, 536 (1988)]. The technique uses the dense ablation cloud surrounding an injected impurity pellet to neutralize a fraction of the incident alpha particles, allowing them to escape from the plasma where their energy spectrum can be measured using a neutral particle analyzer. The signal calculations given in the above-mentioned reference disregarded the effects of the alpha particles' helical Larmor orbits, which causes the alphas to make multiple passes through the cloud. Other effects such as electron ionization by plasma and ablation cloud electrons and the effect of the charge state composition of the cloud, were also neglected. This report considers these issues, reformulates the signal level calculation, and uses a Monte-Carlo ...

Energy Technology Data Exchange (ETDEWEB)

Activities in British Columbia's Fraser Valley generate an estimated 3 million tones of agriculture and food wastes annually, of which 85 per cent are readily available for anaerobic digestion. The potential for energy generation from biogas through anaerobic digestion is approximately 30 MW. On-farm manure-based systems represent the most likely scenario for the development of anaerobic digestion in British Columbia in the near future. Off-farm food processing wastes may be an alternative option to large centralized industrial complexes. Odour control, pathogen reduction, improved water quality, reduced greenhouse gas emissions and reduced landfill usage are among the environmental benefits of anaerobic digestion. The economical benefits include power and heat generation, biogas upgrading, and further processing of the residues to produce compost or animal bedding. This paper described a newly developed anaerobic digestion (AD) calculator that helps users ...

International Nuclear Information System (INIS)

Crystal field calculation and electron paramagnetic resonance (EPR) have been performed on zircon-type materials Nd:YMO_4 (M=V, As, P). Simulation of the energy level schemes has been carried out and the wave functions composition and g tensor principal values associated to the first sub-level of the "4I_9_/_2 manifold were calculated. A rather good correlation is obtained between crystal field calculations and the EPR measurements. Furthermore, some extra lines observed by optical spectroscopy (absorption and emission) also appear on the EPR spectra and a correlation between the two spectroscopies indicates that Nd"3"+-Nd"3"+ exchange and dipolar interactions occur in the zircon family, even at very low doping content (less than 8 x 10"1"9 Nd"3"+ ions cm"-"3). Nd"3"+-Nd"3"+ pairs at distances 3.9, 5.9 and 6.3 A have been identified. (orig.)

International Nuclear Information System (INIS)

For the intermetallic system CaCdsub(1-x)Tlsub(x), 0 <= x <= 1, the Knight shift Ksub(s) of the Cd-NMR and the Tl-NMR were calculated as a function of x, Ksub(s) = Ksub(s)(x). The theoretical investigations were performed on the basis of relativistic augmented-plane-wave (RAPW) band-structure calculations for the boundary phases CaCd and CaTl respectively, and by using the rigid band model for the ternary phases. The density of states and the matrix elements of the relativistic hyperfine operator for electron states at the Fermi surface were calculated in detail. The obtained values were compared with nonrelativistic calculations. The effect of using different exchange potentials was studied for Ksub(s)(Tl). For the Cd-NMR the relativistic effects enhance the nonrelativistic results by a factor of about 1.4. The theoretical value for the Knight shift is smaller than the experimental one by a ...

International Nuclear Information System (INIS)

... radiation effects RADIATIONS. WOOD-PLASTIC COMPOSITES.

International Science & Technology Center (ISTC)

New Composite Multifunctional Coatings Produced Using SHS-Electrodes

International Science & Technology Center (ISTC)

Development of Ceramic Composite Materials and Structural Elements for High-Temperature Nuclear Reactors

International Nuclear Information System (INIS)

The lakes formed in the Amazon floodplain play a key role in sustaining the highest populational density in the Amazon Basin because of its high primary productivity. The water volume in these lakes vary greatly during the year and possible water sources are the feeding river during high water state of the hydrographs and local inputs from its drainage basin. As these sources are chemically distinct, to understand the nutrient dynamics in these lakes, it is very important to know the relative water contribution of different water sources. In this paper we use "1"8O as a conservative to know the water sources for the lakes and our hypothesis is that: 1) In the high water stage lake water is derived predominantly from its feeding river. Therefore their #delta#"1"8O should be similar. 2) In the low water stage lake water is a mixture of watershed and last flood event waters. In this case, lake #delta#"1"8O should be indicative of the relative contribution of each source. To test this ...

Energy Technology Data Exchange (ETDEWEB)

The chemical composition and evolution of produced waters associated with gas production in the Palm Valley gas field, Northern Territory, has important implications for issues such as gas reserve calculations, reservoir management and saline water disposal. The occurrence of saline formation water in the Palm Valley field has been the subject of considerable debate. There were no occurrences of mobile water early in the development of the field and only after gas production had reduced the reservoir pressure, was saline formation water produced. Initially this was in small quantities but has increased dramatically with time, particularly after the initiation of compression in November 1996. The produced waters range from highly saline (up to 300,000 mg/L TDS), with unusual enrichments in Ca, Ba and Sr, to low salinity fluids that may represent condensate waters. The Sr isotopic compositions of the waters ({sup 87}Sr/{sup ...

Energy Technology Data Exchange (ETDEWEB)

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

International Nuclear Information System (INIS)

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

International Nuclear Information System (INIS)

The Si_3N_4-rich corner of the phase diagrams for neodymia and ytterbia containing sialons has been investigated by a systematic variation of the m and n values for compositions between 0.5 and 2.0 with a step size of 0.5. Samples requiring nitrides of the rare earth elements have not been prepared. Sintering has been performed at 1800 C for one hour in a nitrogen atmosphere of 1 MPa. The sintered samples were characterized by X-ray diffraction analysis to identify the crystalline phases in equilibrium with sialon. #alpha#- and #beta#-sialon, the 21R AlN polytypoid, and N-melilite M' were found in the Nd containing system. Materials with Yb showed the formation of #alpha#- and #beta#-sialon, and the AlN polytypoids 12H and 21R. The m and n values of the #alpha#-sialon phase have been calculated via their lattice parameters that were refined by a least squares routine. The occurrence and composition of the phases were used ...

British Library Electronic Table of Contents (United Kingdom)

Platinum Group Element (PGE) concentrations in garnet pyroxenite xenoliths from Oahu, Hawaii, are significantly lower than those in mantle peridotites and show fractionated patterns (e.g. PdN/OsN=2-10, PdN/IrN=4-24; N=chondrite normalized) and very high ReN/OsN ratios (9-248). Mass balance calculations show that the bulk rock pyroxenite PGE inventory is controlled by the presence of sulfide phases. The 187Os/188Os ratios of these pyroxenites vary from subchondritic to suprachondritic (0.123-0.164); and the 187Os/188Os ratios show good correlations with bulk rock and clinopyroxene major and trace element compositions, and bulk rock PGE and sulfur abundances. These observations suggest that the Os isotope compositions in these pyroxenites largely reflect primary processes in the oceanic mant...

International Nuclear Information System (INIS)

A radioactive Waste Incineration System (WIS) with suspension combustion is noticed as effective volume reduction technology of low level radiactive wastes that are increasing every year. In order to demonstrate the decontamination efficiency of ceramic filter used on WIS, this test has been carried out with the test facilities as joint research of Central Research Institute of Electric Power Industry (CRIEPI) and Sumitomo Heavy Industries, Ltd. Miscellaneous combustible waste and power resin, to which 5 nuclides (Mn-54, Fe-59, Co-60, Zn-65, Cs-137) were added, were used as samples for incineration. As the result of the test, it was verified that Decontamination Factor (DF) of the single stage ceramic filter was usually kept over 10"5 for every nuclide, and from the results of above DF, over 10"8 is expected for real commercial plant as a total system. Therefore, it is realized that the off-gas clean up system of the WIS composed of only single ...

International Nuclear Information System (INIS)

To dispose the radioactive waste drums, the waste form's integrity and the nuclides inventories must be assured according to the national and site waste acceptance criteria. Because they might be would gravely affected the performance objectives of disposal site. Our national regulation for the waste inventory related to 'Radioactive Waste Acceptance Criteria' requires that the activities of 13 nuclides and gross #alpha# must be measured and the 95 % of nuclides incorporated in the drum must be identified. It is very difficult to measure the radioactivity with accuracy from the regulated waste drum(200L), and have a large error in the analysis results. In present, there are two system, SGS (Segmented Gamma Scanning System) and TGS (Tomographic Gamma Scanning System) for the analysis of radionuclides from the waste drums. In general, it is known that the accuracy of TGS is below 20 % and that of SGS is below 30 %. The ...

International Nuclear Information System (INIS)

1 - Description: Format: MATXS. Number of groups: 80 neutron-, 24 photon-groups. 97 Nuclides: 1-H-1, 1-H-2, 2-He-3, 2-He-4, 3-Li-6, 3-Li-7, 4-Be-9, 5-B-10, 5-B-11, 6-C- nat., 7-N-14, 7-N-15, 8-O-16, 9-F-19, 11-Na-23, 12-Mg-nat., 13-Al-27, 14-Si-nat., 15-P-31, 17-Cl-nat., 18-Ar-40, 19-K-nat., 20-Ca-nat., 22-Ti-nat., 23-V-nat., 24-Cr-50, 24-Cr-52, 24-Cr-53, 24-Cr-54, 25-Mn-25, 26-Fe-54, 26-Fe-56, 26-Fe-57, 26-Fe-58, 27-Co-59, 28-Ni-58, 28-Ni-60, 28-Ni-61, 28-Ni-62, 28-Ni-64, 29-Cu-nat., 31-Ga-nat., 39-Y-89, 40-Zr-nat., 41-Nb-93, 42-Mo-nat., 47-Ag-107, 47-Ag-109, 48-Cd-nat., 50-Sn-nat., 63-Eu-151, 63-Eu-153, 64-Gd-152, 64-Gd-154, 64-Gd-155, 64-Gd-156, 64-Gd-157, 64-Gd-158, 64-Gd-160, 73-Ta-181, 74-W-182, 74-W-183, 74-W-184, 74-W-186, 75-Re-185, 75-Re-187, 79-Au-197, 82-Pb-nat., 83-Bi-209, 90-Th-232, 91-Pa-233, 92-U-232, 92-U-233, 92-U-234, 92-U-235, 92-U-236, 92-U-237, 92-U-238, 93-Np-237, 93-Np-238, 94-Pu-238, 94-Pu-239, 94-Pu-240, 94-Pu-241, 94-Pu-242, 95-Am-241, ...

Science.gov (United States)

The long-lived nuclides of the americium curium elements are of interest for their use in certain safeguard applications and for nuclear reactor burnup studies in waste management. Recommended values are presented for /sup 241,242m,243/Am, and for /sup 242,243,244,245,246,247,248,250/Cm. These values result from a consistent evaluation of all these half-lives. These preliminary estimates were presented earlier. The uncertainties are provided at the 95% confidence limit for each of the recommended values. It will be noted that many of the recommended errors considerably exceed errors quoted by individual authors in their publication, by up to an order of magnitude, e.g., the total half-life of /sup 242,246,248/Cm and the spontaneous fission half-life of /sup 244/Cm. 65 refs., 18 tabs.

International Nuclear Information System (INIS)

A new evaluation (UKFY2) has been prepared of the independent and cumulative yields of the products of fission induced by thermal, fast, and 14 MeV neutrons in nuclides important for reactor design and operation and for fuel and waste management. Three spontaneously fissioning nuclides were also considered. The evaluation used a database that is considered to be complete up to early 1989. Careful study was made of experimental uncertainties and discrepancies, emphasizing the need for further measurements. Gaps in the data were filled by interpolation and extrapolation, using fits to empirical models. The yields were subsequently adjusted to fit physical constraints of the fissioning process. This paper describes the evaluation, which was submitted and accepted for inclusion in the JEF2 file. The file was produced in January 1990 and a revision of cumulative yield uncertainties distributed in January 1991.

Energy Technology Data Exchange (ETDEWEB)

We have measured production cross-sections of the new neutron-rich isotopes {sup 58}Ti, {sup 61}V, {sup 63}Cr, {sup 66}Mn, {sup 69}Fe, {sup 71}Co and neighbouring isotopes that have been identified as projectile fragments from reactions between a 500 MeV/u {sup 86}Kr beam and a beryllium target. The isotope identification was performed with the zero-degree magnetic spectrometer FRS at GSI, using in addition time-of-flight and energy-loss mesurements. The experimental production cross-sections for the new nuclides and neighbouring isotopes are compared with an empirical parameterization. The resulting prospects for reaching even more neutron-rich isotopes, such as the doubly-magic nuclide {sup 78}Ni, are discussed. (orig.).

International Nuclear Information System (INIS)

We have measured production cross-sections of the new neutron-rich isotopes "5"8Ti, "6"1V, "6"3Cr, "6"6Mn, "6"9Fe, "7"1Co and neighbouring isotopes that have been identified as projectile fragments from reactions between a 500 MeV/u "8"6Kr beam and a beryllium target. The isotope identification was performed with the zero-degree magnetic spectrometer FRS at GSI, using in addition time-of-flight and energy-loss measurements. The experimental production cross-sections for the new nuclides and neighbouring isotopes are compared with an empirical parametrization. The resulting prospects for reaching even more neutronrich isotopes, such as the doubly-magic nuclide "7"8Ni, are discussed. (orig.).

Science.gov (United States)

The use of chemically selective laser ionization combined with beta-delayed neutron counting at ISOLDE has permitted identification and half-life measurements for {sup 61}Mn up through {sup 69}Mn. The 14(4)-ms half life for {sup 69}Mn is one of the shortest determined for any nuclide beyond the sd shell. Gamma-ray singles and coincidence spectra have been determined for the decays of {sup 64,66}Mn to levels of {sup 64,66}Fe, revealing strong deformation and vanishing of the N=40 subshell in the Fe isotopes. {copyright} {ital 1998 American Institute of Physics.}

British Library Electronic Table of Contents (United Kingdom)

Effective integration of nonproliferation management into the design process is key to the broad deployment of advanced nuclear energy systems, and is an explicit goal of the Laser Inertial Fusion Energy (LIFE) project at Lawrence Livermore National Laboratory. The nuclear explosives utility of a nuclear material to a state (proliferator) or sub-state (terrorist) is a critical factor to be assessed and is one aspect of material attractiveness. In this work, we approached nuclear explosives utility through the calculation of a ''figure of merit'' (FOM) that has recently been developed to capture the relative viability and difficulty of constructing nuclear explosives starting from various nuclear material forms and compositions. We discuss the integration of the figure of merit into an asse...

British Library Electronic Table of Contents (United Kingdom)

Glass ceramics are commonly used as sealing materials for planar solid oxide fuel cells (SOFCs). The major requirements of stack and module builders for these materials are the stability of the coefficient of thermal expansion (CTE), excellent bonding (sticking) behaviour and the absence of volatile ingredients, which can lead to changes of the material properties and the sealing ability. SCHOTT Electronic Packaging has developed special glasses and glass-ceramics for various solid oxide fuel cell designs and operating temperatures. The glass compositions are based on the system MgO-Al2O3-BaO-SiO2-B2O3. In this study the evaluation of the developed materials was done by high temperature aging tests for up to 1000h, high temperature XRD-studies and Rietveld calculations, combined with scann...

International Nuclear Information System (INIS)

Collection, analysis and quantification of human factor data are important compositions of human reliability analysis (HRA) and probabilistic risk assessment (PRA). Various human factor databases have been set up, but there are comparatively little human factor data management systems which can be uses for collection, classification, analysis, calculation and predication of the human factor data. Therefore, the human factor data management system for Daya Bay NPP is developed, with the following three modules and four databases: original data module, computing module, introduced data module, and basic database, other data source of the plant, external database and introduced database. The foundational problems about human factor data and the systemic structure and function are described. The data structure in the database is also discussed, because it is of the most importance in the system

Energy Technology Data Exchange (ETDEWEB)

The application of a method for determining the temperature of an oxygen-replenished air stream heated to 2600 K by a hydrogen burner is reviewed and discussed. The purpose of the measurements is to determine the spatial uniformity of the temperature in the core flow of a ramjet test facility. The technique involves sampling the product gases at the exit of the test section nozzle to infer the makeup of the reactant gases entering the burner. Knowing also the temperature of the inlet gases and assuming the flow is at chemical equilibrium, the adiabatic flame temperature is determined using an industry accepted chemical equilibrium computer code. Local temperature depressions are estimated from heat loss calculations. A description of the method, hardware and procedures is presented, along with local heat loss estimates and uncertainty assessments. The uncertainty of the method is estimated at {+-}31 K, and the spatial uniformity was measured within {+-}35 K.

Energy Technology Data Exchange (ETDEWEB)

The emission of air pollutants from road vehicles is the most significant source of air pollution in towns. The chemical composition of these pollutive substances is dependent on the fuel, the type of vehicle and the character of the traffic system. The pollution concentration was measured, (nitrogen oxides and carbon monoxide) in relation to each type of vehicle, in four streets in the Copenhagen area. The system of measurement used was the ''Operational Street Pollution Model'' (OSPM). Results are presented in the form of tables and charts. (AB) 11 refs.

Energy Technology Data Exchange (ETDEWEB)

CMSX-4 superalloy laser beam welds were investigated by transmission electron microscopy and atom probe field-ion microscopy (APFIM). The weld microstructure consisted of fine (10- to 50-nm) irregularly shaped {gamma}` precipitates (0.65 to 0.75 volume fraction) within the {gamma} matrix. APFIM compositions of the {gamma} and {gamma}` phases were found to be different from those in the base metal. Concentration profiles across the {gamma} and {gamma}` phases showed extensive variations of Cr, Co and Al concentrations as a function of distance within the {gamma} phase. Calculated lattice misfits near the {gamma}/{gamma}` interface in the welds are positive values compared to the negative values for base metal. (orig.).

CERN Document Server

Modeling artificial scanning electron microscope (SEM) and scanning ion microscope images has recently become important. This is because of the need to provide repeatable images with a priori determined parameters. Modeled artificial images are highly useful in the evaluation of new imaging and metrological techniques, like image-sharpness calculation, or drift-corrected image composition (DCIC). Originally, the NIST-developed artificial image generator was designed only to produce the SEM images of gold-on-carbon resolution sample for image-sharpness evaluation. Since then, the new improved version of the software was written in C++ programming language and is in the Public Domain. The current version of the software can generate arbitrary samples, any drift function, and many other features. This work describes scanning in charged-particle microscopes, which is applied both in the artificial image generator and the DCIC technique. As an ...

International Nuclear Information System (INIS)

Experimental data on A-15 binary phases (the lattice parameter dependence on composition, phase diagrams, etc.) have been considered and the so-called ''compounds with A-15 structure'' are shown to be solid solutions of element substitution in the structure of A-15 type. Values of lattice parameter and atomic volume of A-15 modifications for 21 elements have been obtained (for Zr, W, Nb, Mo, V in particular). There has been shown the possibility of calculation of atomic volumes and lattice parameters of A-15 binary phases at the lack of direct experimental data. The essential role of atomic volume relations of different phases has been observed for the estimation of stability conditions of A-15 phase.

Energy Technology Data Exchange (ETDEWEB)

This paper presents the application of artificial neural networks to adiabatic flame temperature prediction of hydrocarbon fuels. The investigation was conducted over a wide range of operating conditions in terms of fuel composition, pressure and temperature of reactants, fuel-air equivalence ratio and fuel vapour fraction. Several neural network models for predicting the flame temperature for different applicable fuel ranges were built and examined. The proper preparation of network training data and the appropriate choice of network parameters for achieving better prediction accuracy are discussed. The neural network prediction results were compared with those calculated by a thermodynamic and chemical equilibrium-based computer code - the NASA program CET89. It was shown that trained neural network models can provide the adiabatic flame temperature prediction with a good level of accuracy over a wide range of operating conditions. 16 refs., ...

Energy Technology Data Exchange (ETDEWEB)

The equilibria composition of the gaseous and the solid phase in the system GeO/sub 2//WO/sub 2/ is calculated with an improved thermodynamical program for temperatures 1100 < T < 1400 K and constant volume. By means of the results the experimental observed migration of GeO/sub 2/ in the presence of WO/sub 2/ in a temperature gradient T/sub 2/ ..-->.. T/sub 1/ (1200 ..-->.. 1100 K) in sealed evacuated silica tubes is due to a chemical transport with H/sub 2/ as the transporting agent. The H/sub 2/ is formed by H/sub 2/O which is desorbed by the quartz glass of the ampoules. The also observed volatility of WO/sub 2/ and its deposition in form of Ge/sub 0.75/W/sub 3/O/sub 9/ at the 'cold' end (T/sub 1/) of the tubes is performed by gaseous GeWO/sub 4/. The calculated and experimental transport rates are compared and discussed.

International Nuclear Information System (INIS)

Molar excess volumes, VE, molar excess enthalpies, HE, and speeds of sound data, u, of chloroform (i) + aniline or o-toluidine (j) binary mixtures have been measured as a function of composition at 308.15 K. Isentropic compressibility changes of mixing, ?SE have been determined by employing speed of sound data. Topological investigations of VE data reveals that aniline, chloroform and o-toluidine are associated entities and these (i + j) mixtures contain a 1:1 molecular complex. The IR studies lend further support to the nature and extent of interaction for the proposed molecular entity in the mixtures. HE and ?SE values have also been calculated by employing Moelwyn-Huggins concept [Polymer 12 (1971) 387] taking topology of the constituents of the mixtures. It has been observed that calculated HE and ?SE values compare well with their corresponding experimental values. The observed VE, HE and ?SE data have also been ...

British Library Electronic Table of Contents (United Kingdom)

We present a forward modelling technique for calculating the surface X-ray spectra for a variety of lunar terrains. Our calculations considered variations in solar fluxes from solar quiescent condition to large flare activity (M1 flare), and expected elemental concentrations in the target, as well as yield, instrumental, and viewing geometry parameters for X-ray induced fluorescence from the lunar surface. Additionally, we present estimates of anticipated XRF signals from prominent Ka lines observable by a collimated 14cm2 X-ray detector from a 100km lunar orbit with 20km spatial resolution. Our results show that Mg, Al and Si characteristic Ka lines can be observed for all solar conditions. The Ca Ka lines line can be differentiated from a fixed background during more energetic solar cond...

International Nuclear Information System (INIS)

State-of-the-art approaches for the calculation of gamma heating in LMFBR core, blanket and reflector regions have been evaluated, with particular emphasis on coupled neutron-gamma methods/cross section sets. The major source of calculational error was found to be the apparent failure to impose a mass-energy balance on total gamma energy yield from neutron capture and other interactions in the preparation of representative neutron-gamma cross section sets. The applicability of many simplifying assumptions was demonstrated, including: volume-weighted homogenization, insensitivity to the shape of the gamma-source-spectrum, gamma energy deposition equal to gamma energy source more than 10 cm inside large zones of uniform composition, and the negligible effect of bremsstrahlung. A simple one-group method was developed to permit rapid, accurate estimation of the large (factor of 2) changes in the gamma energy ...

International Nuclear Information System (INIS)

Advanced modality of high-precision radiotherapy fulfilled by a composition of large numbers of small field beams called 'beamlets' can be achieved via nonuniform intensity fluencies. In case of radiation measurements and calculations with narrow high-energy photon beams, however, an accurate two-dimensional dosimetry is a challenging task due to dosimetrically unfavorable phenomena such as dramatic changes of the dose at the field boundaries, dis-equilibrium of the electrons resulting from larger detector volume, and non-uniformity between the detector and the phantom materials. Meanwhile, with the advantages of high spatial resolution and wide range of absorbed doses, there is a growing demand of GAFCHROMICat..EBT film to confirm delivered dose distribution. Especially, the effects from the material differences between the phantom and the film can be minimized in the heterogeneous condition since the GAFCHROMICat..EBT film is composed of ...

Energy Technology Data Exchange (ETDEWEB)

Signal-to-noise-ratio (SNR) thresholds for microarray data analysis were experimentally determined with an oligonucleotide array that contained perfect match (PM) and mismatch (MM) probes based upon four genes from Shewanella oneidensis MR-1. A new SNR calculation, called signal to both standard deviations ratio (SSDR) was developed, and evaluated along with other two methods, signal to standard deviation ratio (SSR), and signal to background ratio (SBR). At a low stringency, the thresholds of SSR, SBR, and SSDR were 2.5, 1.60 and 0.80 with oligonucleotide and PCR amplicon as target templates, and 2.0, 1.60 and 0.70 with genomic DNA as target templates. Slightly higher thresholds were obtained at the high stringency condition. The thresholds of SSR and SSDR decreased with an increase in the complexity of targets (e.g., target types), and the presence of background DNA, and a decrease in the composition of targets, while SBR remained unchanged ...

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PRESTO-II is a computer code developed to evaluate possible health effects from shallow land disposal of low level radioactive wastes. PRESTO-PREP is a data preprocessor that has been developed to expedite the formation of input data sets for PRESTO-II. PRESTO-PREP utilizes a library of nuclide and risk-specific data. Given an initial waste inventory, the code creates the radionuclide portion of the associated input data set for PRESTO-II. 2 references.

International Nuclear Information System (INIS)

The authors present a case in which primary Ewing's sarcoma of the right petrous pyramid in a 9-year-old girl showed no uptake on a /sup 99m/Tc-pertechnetate nuclide angiogram. Intense uptake was present on a /sup 99m/Tc-polyphosphate bone scan, but a static brain scan was only minimally abnormal. The diagnosis and treatment of Ewing's sarcoma are reviewed.

Energy Technology Data Exchange (ETDEWEB)

Gamma scanning measurements are used to determine the radioactive nuclides from an irradiated fuel rod in a hot cell which is a routine task in the Irradiated Materials Examination Facility (IMEF) of the Korea Atomic Energy Research Institute (KAERI), Total gamma spectra of radioactive nuclides and the atomic ratio of {sup 134}Cs to {sup 137}Cs in a few segments of a single fuel rod are measured by the present gamma scanning system. For the purpose of determining the radioactive nuclide's distribution in detail within a fuel rod quantitatively, we attempt to upgrade the present gamma scanning system in this paper, therefore, an investigation of the feasibility of the tomographic gamma scanning (TGS) technique, which is one of the promising nondestructive assay (NDA) methods is proposed. The TGS technique is an efficient method and it has an accurate precision for the characterization of several fuel parameters. In ...

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Norwegian Open Research Archives (NORA)

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Science.gov (United States)

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Energy Technology Data Exchange (ETDEWEB)

Biodiesel consists of long-chain fatty acid esters, derived from renewable sources such as vegetable oils, and its utilization is associated to the substitution of the diesel oil in engines. Depending on the raw material, bio diesel can contain more or less unsaturated fatty acids in its composition, which are susceptible to oxidation reactions accelerated by exposition to oxygen and high temperatures, being able to change into polymerized compounds. The objective of this work was to determine the oxidative stability of bio diesel produced by ethanolysis of neutralized, refined, soybean frying oil waste, and partially hydrogenated soybean frying oil waste. The evaluation was conducted by means of the Rancimat equipment, at temperatures of 100 and 105 deg C, with an air flow of 20 L h{sup -1}. The fatty acid composition was determined by GC and the iodine value was calculated. It was observed that even though the ...

Energy Technology Data Exchange (ETDEWEB)

As an explosion develops in the collapsed core of a massive star, neutrino emission drives convection in a hot bubble of radiation, nucleons, and pairs just outside a proto-neutron star. Shortly thereafter, neutrinos drive a wind-like outflow from the neutron star. In both the convective bubble and the early wind, weak interactions temporarily cause a proton excess (Y{sub e} {approx}> 0.50) to develop in the ejected matter. This situation lasts for at least the first second, and the approximately 0.05-0.1 M{sub {circle_dot}} that is ejected has an unusual composition that may be important for nucleosynthesis. Using tracer particles to follow the conditions in a two-dimensional model of a successful supernova explosion calculated by Janka, Buras, and Rampp (2003), they determine the composition of this material. most of it is helium and {sup 56}Ni. The rest is relatively rare species produced by the decay of ...

International Science & Technology Center (ISTC)

Thermodynamic Stable Metal Compositions for Improvement of an Operational Safety of Constructional Materials under Conditions of Multifactor Loadings of an Aggressive Environment

Science.gov (United States)

... Accession Number : ADD345858. Title : Nondestructive Testing of Polymeric Composite Sandwich Panels Via the Thermographic Halo,. ...

Science.gov (United States)

... Abstract : High temperature testing of graphite/epoxy laminates and composite sandwich panels was performed while the Shuttle was on orbit to ...

Science.gov (United States)

the progressive simplification of composite sandwich panels. The equations ... The thermal and structural behavior of composite sandwich panels with a ...

Science.gov (United States)

... polypropylene, polylactic acid and polyvinyl chloride to form wood plastic composites (WPC). WPCs have seen a large growth in ... ...

Energy Technology Data Exchange (ETDEWEB)

The radionuclide characteristics of light-water-reactor (LWR) spent fuel play key roles in the design and licensing activities for radioactive waste transportation systems, interim storage facilities, and the final repository site. Several areas of analysis require detailed information concerning the time-dependent behavior of radioactive nuclides including (1) neutron/gamma-ray sources for shielding studies, (2) fissile/absorber concentrations for criticality safety determinations, (3) residual decay heat predictions for thermal considerations, and (4) curie and/or radiological toxicity levels for materials assumed to be released into the ground/environment after long periods of time. The crucial nature of the radionuclide predictions over both short and long periods of time has resulted in an increased emphasis on thorough validation for radionuclide generation/depletion codes. Current radionuclide generation/depletion codes have the capability to follow the ...

Energy Technology Data Exchange (ETDEWEB)

Chemical composition of fine aerosol particles over the northern Chilean coastal waters was determined onboard the U.S. DOE G-1 aircraft during the VOCALS (VAMOS Ocean-Cloud-Atmosphere-Land Study) field campaign between October 16 and November 15, 2008. SO42-, NO3-, NH4+, and total organics (Org) were determined using an Aerodyne Aerosol Mass Spectrometer, and SO42-, NO3-, NH4+, Na+, Cl-, CH3SO3-, Mg2+, Ca2+, and K+ were determined using a particle-into-liquid sampler-ion chromatography technique. The results show the marine boundary layer (MBL) aerosol mass was dominated by non- sea-salt SO42- followed by Na+, Cl-, Org, NO3-, and NH4+, in decreasing importance; CH3SO3-, Ca2+, and K+ rarely exceeded their respective limits of detection. The SO42- aerosols were strongly acidic as the equivalent NH4+ to SO42- ratio was only ~0.25 on average. NaCl particles, presumably of sea-salt origin, showed chloride deficits but retained Cl- typically more than half the ...

Energy Technology Data Exchange (ETDEWEB)

Polychlorinated dibenzo-p-dioxins and dibenzo-furans form a family of more than 200 compounds which are relatively stable in the biosphere and tend to accumulate in the human body. The tetra- to hexa-chlorinated dioxins and furans are considered highly toxic. To facilitate the assessment of the total toxicity of dioxin and furan mixtures, the estimated toxic effects of the individual compounds relative to the 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) were introduced as Toxic Equivalent Factors which yield, when multiplied with the respective concentrations, the Toxic Equivalent (TE) of the mixture. Toxic dioxins and furans are unintentionally formed in a number of industrial combustion processes such as waste incineration and iron ore sintering, in the chemical industry and in household heating. To keep the emissions as low as possible, off-gas clearing systems for the collection of dioxins and furans are increasingly prescribed by the authorities. In addition, it appears desirable ...

Energy Technology Data Exchange (ETDEWEB)

Coal fired combined cycle power systems will be a sufficient way to increase the efficiency of coal combustion. However, combined cycle power systems require a reliable hot gas cleanup. Especially alkali metals, such as sodium and potassium, can lead to hot corrosion of the gas turbine blading if they condensate as sulphates. The actual work deals with the release and sorption of alkali metals in coal fired combined cycle power systems. The influence of coal composition, temperature and pressure on the release of alkali species in coal combustion was investigated and the relevant release mechanisms identified. Alumosilicate sorbents have been found that reduce the alkali concentration in the hot flue gas of the Circulating Pressurized Fluidized Bed Combustion 2{sup nd} Generation (CPFBC 2{sup nd} Gen.) at 750 C to values sufficient for use in a gas turbine. Accordingly, alumosilicate sorbents working at 1400 C have been found for the Pressurized Pulverized Coal ...

Energy Technology Data Exchange (ETDEWEB)

The fixed bed pilot plant, the catalyst testing procedure, and the calculations for conversion and selectivities were previously described in the technical progress report covering the period of 3/16/88 to 6/16/88 for Contract DE-AC22-87PC79812. Conversions and hydrocarbon selectivities were calculated using data from an on-line gas chromatography (GC) analyzer. Alcohol selectivities were calculated using data from an on-line boiling point GC analyzer which analyzed the liquid product. The catalysts were prepared via the steps of impregnation, calcination, and reduction on a special Y-zeolite-derived support. The impregnation step consisted of evaporation of metal salts on to the support from an aqueous solution. For one catalyst (No. 6531-188) the metal salts were evaporated on to the support from a reverse micelle solution containing the metal salts. All the catalysts were calcined for four hours at 450{degree}C. The ...

International Nuclear Information System (INIS)

The molar heat capacities (Cp,m) of a series of synthetic forsterite (Fo)-fayalite (Fa), (Mg2SiO4+Fe2SiO4), olivines have been measured between 5K and 300K on milligram-sized samples with the Physical Properties Measurement System (Quantum Design(R)). Sharp, ?-type heat capacity anomalies are observed in the Fe-rich compositions fayalite, Fo10Fa90, Fo20Fa80, Fo30Fa70, and Fo40Fa60. The corresponding Neel temperatures TN decrease linearly from 64.5K in fayalite to 32.8K in Fo40Fa60 following the relationship TN=79.02.xFa-14.07. Fo50Fa50 and Mg-richer olivines show weak broad features in the heat capacity data around 15K to 20K that decrease in magnitude with increasing forsterite content. In order to derive and separate molar electronic, magnetic and vibrational heat capacity contributions, Cel,m, Cmag,m, and Cvib,m from the experimental heat capacities (Ctot,m), we used a single-parametric phonon dispersion model to calculate Cvib,m for the ...

International Nuclear Information System (INIS)

Silicon/carbon composite anode materials were prepared by pyrolyzing the phenol-formaldehyde resin (PFR) mixed with silicon and graphite powders. Scanning electron microscopic (SEM) observation showed that the morphology stability of the composite electrodes can be retained during cycling. A structure evolution mechanism is proposed to illuminate the enhancement of cycleability of the composite electrode. The composite used as anode material for lithium ion batteries possesses a reversible capacity of over 700 mAh/g.

Energy Technology Data Exchange (ETDEWEB)

A trans-uranium (TRU) fuel should be manufactured and loaded in transmutation systems in order to transmute the long-lived TRU nuclides into short-lived ones. However, since all of the TRU nuclides are not completely transmuted in one cycle lifetime in transmutation systems, the spent TRU fuel has to be treated to recover the long-lived radionuclides or fuel matrix materials. One concept to manufacture TRU fuel for transmutation is to recover uranium from TRU and molten salt. If this type of fuel is adopted for transmutation, uranium could also be an objective material to be recovered and recycled. Since electrowinning is a promising technology to be employed for the recovery of uranium from fuel materials, some experimental work of electrowinning using anode of Cd-Li alloy was carried out in this study. The basic salt chosen was a mixture of LiCl-KCl which has an eutectic point at 357 .deg. C.

International Nuclear Information System (INIS)

To reduce the volume of radioactive wastes after evaporation, activity carriers can be separated from the inactive salt load. Boric acid separation from PWR concentrates was considered a preliminary stage for nuclide precipitation. In connection with the precipitation process, the reaction conditions for boric acid separation were determined by bench-scale experiments. After evaluating the known purification processes, crystallization was suggested as a practicable method. After inactive bench-scale experiments, mixed crystal formation with iron hexacyanoferrate for Cs removal was chosen. The disturbing effect of the complexing agents was neutralized by a pre-dose of iron-III-salts. By specifying the precipitation conditions, for Cs-134 an activity separation from 3,0 E + 06 Bg/l to 1,9 E + 02 Bg/l, and for Cs-137 from 5,9 E + 06 Bg/l to 1,2 E + 02 Bg/l was achieved. Accordingly, the decontamination factor for Cs-134 was 16000, and for Cs-137 48000. For the ...

Energy Technology Data Exchange (ETDEWEB)

A pyrochemical process has been introduced and utilized so that the transmutation of spent PWR fuel in PEACER can produce mainly low and intermediate level waste for near surface disposal. Major radioactive nuclides from PEACER pyroprocessing are composed of TRU and LLFP. In this study, the requirement for the final waste from PEACER is evaluated based on the methodology for establishment of waste acceptance criteria. Also, sensitivity analysis for several input parameters is conducted in order to determine acceptable decontamination factor (DF) and LLFP removal efficiency and to find out input parameter that extremely have an effect on DF. As a result of the study, LLFP removal efficiency, especially Sr-90 and Tc-99, is proved to be a major nuclide which contributes to annual dose by human intrusion scenario rather than TRU DF. More than 98.5% of LLFP have to be removed to meet below dose constraint within the DF more than 5.0E + 03. Besides, ...

International Nuclear Information System (INIS)

In this work, densities #rho#, speeds of sound u, and viscosities #eta#, have been measured over the whole composition range for the binary mixtures of diethylene glycol monomethyl ether (DEGMME), CH_3(OCH_2CH_2)_2OH with 1-hexanol, CH_3(CH_2)_5OH, 1-octanol, CH_3(CH_2)_7OH, and 1-decanol, CH_3(CH_2)_9OH at T = (293.15, 298.15, 303.15, and 308.15) K along with the properties of the pure components. By using the experimental values of #rho#, u, and #eta#, excess molar volume, V_m"E, deviations in viscosity, #DELTA##eta#, isentropic compressibility #kappa#_S, deviations in isentropic compressibility #DELTA##kappa#_S, deviations of the speed of sound #DELTA#u, have been calculated. The viscosity results have also been analysed in terms of some semi-empirical equations.

International Nuclear Information System (INIS)

Molar excess volumes, VE, molar excess enthalpies, HE, and speeds of sound, u, of o-toluidine (i) + cyclohexane or n-hexane or n-heptane (j) binary mixtures have been determined over entire range of composition at 308.15 K. Speeds of sound data have been utilized to predict isentropic compressibility changes of mixing, ?SE of (i + j) mixtures. The observed VE, HE and ?SE data have been analyzed in terms of Graph theory. The analysis of VE data by Graph theory reveals that o-toluidine exists as an associated molecular entity and (i + j) mixtures contain 1:1 molecular complex. It has been observed that VE, HE and ?SE values calculated by Graph theory compare well with their corresponding experimental values. The observed data have also been analyzed in term of Flory theory.

International Nuclear Information System (INIS)

The Flory model is applied to predict the isobaric expansion coefficients, ?P, isentropic, ?S, and isothermal, ?T, compressibilities and speeds of sound, u, of the highly complex mixtures: hydroxyether + alkane, + dibutylether, + 1-butanol or + 2-methoxyethanol, 1-alkanol + alkane, and 1-alkanol + dibutylether. Predictions were obtained using the energetic parameter, ?12, determined from values of excess enthalpies, HE, and from values of the excess isochoric internal energies, UVE, at equimolar composition. No meaningful differences exist between such predictions. Deviations between experimental and calculated values are lower than 2% for mixtures containing alkoxyethanols. Poorer results are obtained for 1-alkanol + dibutylether mixtures with deviations up to 5%. It is shown that predictions on ?P, ?S, ?T, and u essentially depend on structural effects and not on the orientational effects present in the studied mixtures. Results are improved ...

International Nuclear Information System (INIS)

The detailed electronic energy band structure of hexagonal close-packed #alpha#-zirconium, corresponding to the atomic configuration of 4d"25s"2 of its four outermost valence electrons, has been computed by the composite-wave variational version of the augmented-plane-wave(APW) method in conjunction with the X#alpha#(#alpha# = 0.70424) exchange approximation for obtaining the potentials. From these data the electronic density of states and its angular-momentum-decomposed components have been obtained by the Raubenheimer-Gilat method. These quantities are required in order to calculate the electron-phonon interaction parameter (lambda) and the superconducting transition temperature (Tsub(c)) within the framework of the theories of Gaspari and Gyorffy and McMillan. A study of the variation of Tsub(c) with the Coulomb pseudopotential (#mu#*) revealed that #mu#* = 0.1 yields the best agreement between theory and experiment for #alpha#-Zr. Also ...

Energy Technology Data Exchange (ETDEWEB)

In this study, WO{sub 3} thin films were grown on glass substrates using an aqueous solution containing tungstate (NH{sub 4}){sub 2}WO{sub 4} as precursor. The substrate temperature incremented from 250 to 500 deg. C, by steps of 50 deg. C. The structural properties were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. Microprobe analyses showed that a balanced stoichiometric composition was obtained for thin films prepared at T{sub s} = 350 and 400 deg. C. The X-ray diffraction analyses showed different structure crystallography in function of the substrate temperature. Moreover, films deposited at 400 deg. C were annealed in air for 2 h at 450 and 500 deg. C, respectively and the structural changes due to heat treatment were studied. Finally, the optical properties of these films were carried out using optical measurements of transmittance T({lambda}) and reflectance R({lambda}) spectra in 300-1800 nm domain. The ...

International Nuclear Information System (INIS)

The transfer kinetics of the negatively charged glycosphingolipid II"3-N-acetylneuraminosyl-gangliotetraosylceramide (GM_1) were investigated by monitoring tritiated GM_1 movement between donor and acceptor vesicles. After appropriate incubation times at 45 "0C, donor and acceptor vesicles were separated by molecular sieve chromatography. Donors were small unilamellar vesicles produced by sonication, whereas acceptors were large unilamellar vesicles produced by either fusion or ethanol injection. Initial GM_1 transfer to acceptors followed first-order kinetics with a half-time of about 40 h assuming that GM_1 is present in equal mole fractions in the exterior and interior surfaces of the donor vesicle bilayer and that no glycolipid flip-flop occurs. GM_1 net transfer was calculated relative to that of ["1"4C]cholesteryl oleate, which served as a nontransferable marker in the donor vesicles. Factors affecting the GM_1 interbilayer transfer rate included phospholipid ...

Energy Technology Data Exchange (ETDEWEB)

Petrographic research for the Nevada Nuclear Waste Storage Investigations focused on xenolithic variability in the Topopah Spring Member and on variations of clinoptilolite composition at Yucca Mountain. Zeolite and smectite occurrences were considered in terms of their relation to a disturbed zone beneath the potential repository, and mineral stability experiments have produced a new clinoptilolite structure as a result of prolonged heating at low temperature. Limitations were defined on the abundance of erionite and of sulfur. X-ray diffraction studies lead to improved analytical methods. Progress was made in the comparative study of mineralogy in sand ramps and in faults. Geological modeling considered the differences of the diffusion of nonsorbing tracers in vertically and in horizontally fractured rock. Modeling also treated the diffusion of a nonsorbing tracer in devitrified and in zeolitized rock. The results of these experiments in all cases show relatively ...

Energy Technology Data Exchange (ETDEWEB)

The aim of this study as to determine the mechanisms involved in using ammonium fluoborate as a reducing atmosphere when preheating a high magnesium content aluminium alloy. Rutherford Backscattering (RBS) has been the major technique used in the analysis of samples, it revealed significant reduction in both the diffusion of magnesium to the surface and the calculated oxide thickness in the presence of NH{sub 4}BF{sub 4}. At temperatures above 500 deg C in air, SEM images revealed depressions and voids due to incipient melting at various stages, around the grain boundaries. Grain boundaries effectively acted as pipes aiding the diffusion of magnesium to the surface. These results have been verified through compositional analysis with both RBS and auger electron spectroscopy (AES). Results from NH{sub 4}BF{sub 4} atmosphere preheat conditions showed significant improvements. It was verified experimentally that above 500 deg C , AA5182 alloys ...

Energy Technology Data Exchange (ETDEWEB)

A laboratory differential simulation method is used for the design of carbonization columns at coal-tar processing in which phenols are regenerated from phenolate solution by carbon dioxide absorption. The design method is based on integration of local absorption rates of carbon dioxide along the column. The local absorption rates into industrial phenolate mixture are measured in a laboratory model contactor for various compositions of the gas and liquid phases under the conditions that ensure the absorption rates in the laboratory absorber simulate the local rates in the industrial column. On the bases of the calculations, two-step carbonization columns were designed for 30000 t/year of the phenolate solution treatment by carbon dioxide. The absorption proceeds at higher pressure of 500 kPa and temperatures from 50 to 65 C, pure carbon dioxide is used and toluene is added. These conditions have the following favourable effects: (I) significant ...

International Nuclear Information System (INIS)

Distributed Bragg reflectors (DBRs) composed of In_0_._5Al_0_._5P/In_0_._5(Al_yGa_1_-_y)_0_._5P quarter-wave layers have been prepared using metalorganic vapor phase epitaxy. The structures were grown over a wide range of high-index layer composition (0#<=#y#<=#0.6) and peak reflectivity wavelength (720 nm#<=##lambda##<=#565 nm, covering the spectrum from deep red to green). In all cases observed and calculated reflectance spectra were in excellent agreement. Using these DBRs, an undoped all-phosphide visible vertical cavity surface-emitting laser structure was grown. Under pulsed optical excitation at room temperature, lasing was obtained at a wavelength of #lambda##approx#670 nm, with a threshold power density comparable to that observed from similar structures prepared using AlAs/AlGaAs DBRs.

International Nuclear Information System (INIS)

It is very well known that the CANDU reactor has positive Coolant Void Reactivity (CVR), which is most important criticisms about CANDU. The most recent innovations based on using a thin absorbent Hafnium shell in the central bundle element were successfully been applied to the Advanced CANDU Reactor (ACR) project. The paper's objective is to analyze elementary lattice cell effects in applying such methods to reduce the CVR. Three basic fuel designs in their corresponding geometries were chosen to be compared: the ACR-1000TM, the RU-43 (developed in INR Pitesti) and the standard CANDU fuel. The bundle geometry influence on void effect was also evaluated. The WIMS calculations proved the Hafnium absorber suitability (in the latest 'shell design') to achieve the negative CVR target with great accuracy for the ACR-1000 fuel bundle design than for the other two projects. (authors)

Energy Technology Data Exchange (ETDEWEB)

The cost of transporting biogas digestate can be decreased by reducing its water content. However, the digestate emits volatile compounds during drying. This study investigated the drying behaviour and the change of digestate composition. Drying took place in a hybrid solar/waste-heat dryer that used solar energy as well as waste heat from a combined heat and power unit (CHP) and the exhaust air of a microturbine. The experiment involved the use of 60 t of liquid digestate. Climatic conditions were measured inside and outside the drying hall. Dry matter (DM) and organic dry matter (ODM) were also measured on a daily basis. In addition, the energy consumption of waste and solar heat were recorded and related to the quantity of dried feedstock. The total nitrogen, ammonium, phosphate, potassium oxide, magnesium oxide and calcium oxide in the digestate were subjected to chemical analysis before and after the drying process. Losses of nitrogen were ...

International Nuclear Information System (INIS)

The feasibility of developing a fusion power monitor based on a fluid activation detector is considered here. The activation fluid may be either a liquid or a gas and its composition can be selected from a number of candidate materials to provide desired activation and decay characterisitcs. Performance calculations indicate that ordinary water would be a nearly ideal activation fluid. The "1"6O(n,p)"1"6N reaction has a threshold at about 10 MeV and a cross section energy dependence giving it a predominant response for unmoderated D-T fusion neutrons. Adequate activation can be obtained at moderate flow rates for remote counting away from the high radiation area of the reactor. The 7.16 sec half-life of "1"6N is ideal for remote counting with subsequent decay in a small hold-up tank to eliminate activity build-up in the recycled water.

International Nuclear Information System (INIS)

Complex formation between neptunium(IV) and neptunium(V) ions with thiosemicarbazidodiacetic acid in solution has been studied spectrophotometrically. Under the conditions employed herein complexes of composition 1:2 and 1:1, in the form Np(HR)_2 and NpO_2R"2"-, respectively, are formed. Stability constants for these complexes have been calculated and their molar extinction coefficients have been determined, and are equal to (1.33 +/- 0.25) x 10"7, log #beta# = 7.11 +/- 0.8, element of/sub K/ = 96 +/- 3 liter/mole x cm for Np(HR)_2, and (2.34 +/- 0.2) x 10"3, log #beta# = 3.36 +/- 0.036, element of/sub K/ = 235 +/- 1 liter/mole x cm for NpO_2R"2"-. Spectrophotometric titration has also shown that in basic solutions thiosemicarbazidodiacetic acid behaves as a tribasic acid; it third ionization constant has been determined and is equal to 10/sup -9.2/.

International Nuclear Information System (INIS)

We present a comprehensive, up-to-date compilation of band parameters for the technologically important III - V zinc blende and wurtzite compound semiconductors: GaAs, GaSb, GaP, GaN, AlAs, AlSb, AlP, AlN, InAs, InSb, InP, and InN, along with their ternary and quaternary alloys. Based on a review of the existing literature, complete and consistent parameter sets are given for all materials. Emphasizing the quantities required for band structure calculations, we tabulate the direct and indirect energy gaps, spin-orbit, and crystal-field splittings, alloy bowing parameters, effective masses for electrons, heavy, light, and split-off holes, Luttinger parameters, interband momentum matrix elements, and deformation potentials, including temperature and alloy-composition dependences where available. Heterostructure band offsets are also given, on an absolute scale that allows any material to be aligned relative to any other. [copyright] 2001 American ...

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The relationship between coal properties and liquefaction or gasification characteristics was analyzed by using the analysis and test results and liquefaction characteristics in the coal data base. On liquefaction reaction, the close relation between an oil yield and coal constituent composition or a coal rank is well-known. Various multivariable regression analyses were conducted by using 6 factors as variables such as calorific value, volatile component, O/C and H/C atomic ratios, exinite+vitrinite content and vitrinite reflectance, and liquefaction characteristics as variate. On liquefaction characteristics, the oil yield of dehydrated and deashed coals, asphaltene yield, hydrogen consumption, produced water and gas quantities, and oil+asphaltene yield were predicted. The theoretical gasification efficiency of each specimen was calculated to evaluate the liquefaction reaction obtained. As a result, the oil yield increased with H/C atomic ...

International Nuclear Information System (INIS)

Novel hybrid organic/inorganic nanocomposites made of metal oxide and conjugated polymer nanocomposite and its application in bulk-heterojunction solar cells were studied. The composite was composed of different concentrations of strontium titanate (SrTiO_3) and polyaniline doped phosphoric acid. The optimum concentration of strontium titanate was found to be 0.2 v/v. An inorganic-organic photovoltaic device with a structure of Ag/Pani-H_3PO_4-SrTiO_3/Al has been fabricated. The ideality factor value of the diode was found to be 1.8. This n value of the diode implies a deviation from ideal junction behaviour. The barrier height #phi#_b value for the diode was found to be 0.56 eV. The Ag/Pani-H_3PO_4-SrTiO_3/Al diode shows a photovoltaic behaviour with a maximum open-circuit voltage V_o_c of 2.49 V, and short-circuit current I_s_c of 5.6 mA under light illumination #lambda# = 460 nm. The conversion efficiency was found to be 5.2%. It is evaluated that the ...

International Nuclear Information System (INIS)

The "8"8Y decay has been studied with the aim to discover emission of monohromatic positrons (MP). The "8"8Sr(d,2N) reaction was used for production of "8"8Y (#beta#"+, Tsub(1/2)=106.6 days) nuclides. The prismatic beta spectrometer has been used to measure spectra of electrons and positrons. No MPs have been found. The resulting upper bound for their emission rate turned out to be lower than theoretically expected one.

International Nuclear Information System (INIS)

This paper introduces the inter-comparison results of some environmental radioactivity monitoring items for Daya Bay nuclear power plant. The inter-comparison was organized by China Institute for Radiation Protection and five laboratories participated in it. The compared items included total #beta# in kelp and sediment, "3H in water, "9"0Sr in soil, artificial nuclides "1"1"0"mAg, "2"4"1Am, "1"0"9Cd, "5"7Co in kelp and sediment. Inter-comparison results are analyzed as well

Energy Technology Data Exchange (ETDEWEB)

The decontamination of the urban building surfaces, based on the covering of clay suspensions, has been studied. Contaminated samples for test purpose were prepared by application of radioactive solution which was extracted from the soil of 2 km zone of the Chernobyl Nuclear Power Plant(ChNPP). The cation converting conditions of clay suspensions were determined by the experiments of swelling and stability of the suspensions. According to the experimental results, the most effective clay suspension was the NH{sub 4}-type which had a 7.1 of decontamination factor(DF) on Cs and 4.5 of DF on total nuclides after 3 times covering on slate.

Science.gov (United States)

The analysis of complex fluids such as crude oils, fuels, vegetable oils and mixed waste streams poses significant challenges arising primarily from the multiplicity of components, the different properties of the components (polarity, polarizability, etc.) and matrix properties. We have recently introduced an analytical strategy that simplifies many of these analyses, and provides the added potential of linking compositional information with physical property information. This aspect can be used to facilitate equation of state development for the complex fluids. In addition to chemical characterization, the approach provides the ability to calculate thermodynamic properties for such complex heterogeneous streams. The technique is based on the advanced distillation curve (ADC) metrology, which separates a complex fluid by distillation into fractions that are sampled, and for which thermodynamically consistent temperatures are measured at ...

International Nuclear Information System (INIS)

Intermetallic compounds based on the Al-Co system were synthesized by solid state method - mechanical alloying and their properties were investigated using XRD, SEM, and DSC. The powder was used to make new targets of irradiation for gamma sources in order to enhance the specific activity and to reduce the consumption of material. The intermetallic compound AlCo was formed in the first 4 hours of milling. After 8 hours of milling the medium size of crystallites were of 5.58 nm. This value decreases with the increase of milling time up to 3 nm, corresponding to the 28 hours of grinding. There was calculated and plotted the Gibbs function, #DELTA#_f"0, for the reaction of formation AlCo and Al_3Co from the Al-Co system. It had negative values over the entire range of temperatures for both investigated compounds. After 28 hours milling a phase composition was obtained as follows: 0.2% Al; 21%Co ; 55.5%AlCo; 23.3% Al_1_3Co_4. AlCo 98% has been ...

International Nuclear Information System (INIS)

The chemical composition and evolution of formation waters associated with gas production in the Palm Valley field, Northern Territory, has important implications for reservoir management, saline water disposal, and gas reserve calculations. Historically, the occurrence of saline formation water in gas fields has been the subject of considerable debate. A better understanding of the origin, chemical evolution and movement of the formation water at Palm Valley has important implications for future reservoir management, disposal of highly saline water and accurate gas reserves estimation. Major and trace element abundance data suggest that a significant component of the highly saline water from Palm Valley has characteristics that may have been derived from a modified evaporated seawater source such as an evaporite horizon. The most dilute waters probably represent condensate and the variation in the chemistry of the intermediate waters suggests ...

International Nuclear Information System (INIS)

Effect of nitrogen-containing additives in the study of wood plastic composites of MMA with simul and mango wood of Bangladesh has been investigated. Nine different additives were used and the additives containing carboamide group induce the highest tensile strength to the composite. (author).

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A composite is any combination of two or more resources held together by some type of mastic or matrix. This report will describe several different types of composites with regard to thermoplasticization, improved mechanical properties, and stiffness.

UK PubMed Central (United Kingdom)

Dimethacrylate polymers and composites are seeing increased usage in orthopedics. As these applications require the material to integrate with the surrounding tissues, direct contact cytotoxicity...Full Text Available

International Nuclear Information System (INIS)

1 - Description of program or function: Format: MATXS; Number of groups: 175 neutron-, 42 photon-groups; 176 Nuclides: 1-H-1, 1-H-2, 1-H-3, 2-He-3, 2-He-4, 3-Li-6, 3-Li-7, 4-Be-9, 5-B-10, 5-B-11, 6-C- nat., 7-N-14, 7-N-15, 8-O-16, 8-O-17, 9-F-19, 11-Na-23, 12-Mg-nat., 13-Al-27, 14-Si-nat., 14-Si-28, 14-Si-29, 14-Si-30, 15-P-31, 16-S-32, 17-Cl-nat., 19-K-nat., 20-Ca-nat., 21-Sc-45, 22-Ti-nat., 23-V-nat., 24-Cr-50, 24-Cr-52, 24-Cr-53, 24-Cr-54, 25-Mn-25, 26-Fe-54, 26-Fe-56, 26-Fe-57, 26-Fe-58, 27-Co-59, 28-Ni-58, 28-Ni-60, 28-Ni-61, 28-Ni-62, 28-Ni-64, 29-Cu-63, 29-Cu-65, 31-Ga-nat., 39-Y-89, 40-Zr-nat., 40-Zr-90, 40-Zr-91, 40-Zr-92, 40-Zr-94, 40-Zr-96, 41-Nb-93, 42-Mo-nat., 46-Pd-102, 46-Pd-104, 46-Pd-105, 46-Pd-106, 46-Pd-108, 46-Pd-110, 47-Ag-107, 47-Ag-109, 48-Cd-106, 48-Cd-108, 48-Cd-110, 48-Cd-112, 48-Cd-113, 48-Cd-114, 48-Cd-116, 49-In-nat., 53-I-127, 54-Xe-124, 54-Xe-126, 54-Xe-128, 54-Xe-129, 54-Xe-130, 54-Xe-131, 54-Xe-132, 54-Xe-134, 54-Xe-136, 55-Cs-133, ...

UK PubMed Central (United Kingdom)

The relative role of the maternal source and the filial sink in controlling the composition of maize (Zea mays L.) kernels is unclear and may be influenced by the genotype and the N...Full Text Available

Science.gov (United States)

Composite Sandwich Panels under Different Thermal Environments, Composite Structures, Vol. 25,. July 1993, pp. 227239. 11. Ko, William L., Mechanical and ...

Energy Technology Data Exchange (ETDEWEB)

As a new composition of matter, alkali metal or ammonium or tetraalkylammonium diazidoperfluorophthalocyanatoferrate. Other embodiments of the invention comprise compositions wherein the metal of the coordination complex is cobalt, manganese and chromium.

Science.gov (United States)

... Accession Number : ADD442819. Title : Instrumeted Impact Testing of Composite Sandwich Panels,. Corporate Author : AUBURN UNIV AL. ...

Science.gov (United States)

hlgh fiber content composites met the minlmum requirements. (1400 O F ) , the hlgher fiber content as-fabricated composites have impact strengths distinctly ...

Science.gov (United States)

The objectives of the Phase-I research address the development of mechanics- based structural integrity analysis methodologies for composite sandwich panels ...

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We study the signals for composite vector leptoquarks in [ital e][sup +][ital e[minus

Science.gov (United States)

We advance a tentative composite model for computer security at JPL, together with inter and intra networking with other NASA centers and overseas clients.

Energy Technology Data Exchange (ETDEWEB)

The presented paper describes the formulation of the fractional mass balances which are used to calculate the concentration and size distribution of char in the balance cells of a circulating fluidized bed boiler. In case of using the shrinking core model additionally the distribution of conversion of the char particles is calculated. Basically two reaction models (a shrinking particle and a shrinking core model) are available to describe the combustion process. The model considers all essential physico/chemical phenomena (primary fragmentation, attrition, mass transfer to gas phase) which have to be taken into account for the description of the combustion process. The model is part of an overall simulation program for circulating fluidized bed boilers. This engineering simulator has been developed to return the main performance parameters of such systems like temperature along the furnace height, size distribution of balanced solid components, ...

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Volumetric properties of liquid mixtures of neon and hydrogen have been calculated using path integral hybrid Monte Carlo simulations. Realistic potentials have been used for the three interactions involved. Molar volumes and excess volumes of these mixtures have been evaluated for various compositions at 29 and 31.14 K, and 30 atm. Significant quantum effects are observed in molar volumes. Quantum simulations agree well with experimental molar volumes. Calculated excess volumes agree qualitatively with experimental values. However, contrary to the existing understanding that large positive deviations from ideal mixtures are caused due to quantum effects in Ne{endash}H{sub 2} mixtures, both classical as well as quantum simulations predict the large positive deviations from ideal mixtures. Further investigations using two other Ne{endash}H{sub 2} potentials of Lennard{endash}Jones (LJ) type show that excess volumes are very ...

International Nuclear Information System (INIS)

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

International Nuclear Information System (INIS)

The first-principles energetics of the constituent elements Ca and Mg and the Mg_2Ca C14 laves phase (C14) in the Ca-Mg binary system were used in the computational thermodynamic modeling, with models for the Gibbs energy of individual phases. C14 was modeled as (Ca,Mg)_2(Ca,Mg)_1 with four end-members. The first-principles calculations were performed using two computer codes: (i) WIEN2K based on the full-potential linearized augmented plane-wave (FLAPW) method and (ii) VASP based on the pseudo-potentials and a plane wave basis set. The total energies of the pure Ca and Mg in the fcc, bcc, and hcp structures, three laves phase structures of Mg_2Ca, and the four end-members of C14 were calculated at 0 K. The enthalpies of formation of the four end-members were obtained accordingly and used as input data in evaluating the Gibbs energy functions of C14. The entropy contribution in the Gibbs energy function for C14 was obtained through its liquidus ...

Science.gov (United States)

This Dissertation presents the author's investigation and development of a systematic method for evaluating the aerodynamic performance of Vertical Axis Wind Energy Capture Systems (WECS) apart from their electrical generation capability. The current standard method for specifying a wind energy machine is to discuss its rated power in kilowatts (or megawatts when capacity exceeds 100 kW). While this holistic method is effective for comparing machines it does not reveal the essential characteristics necessary for optimization of individual machine components. The method developed herein separates the performance characteristics of the WECS from the generation characteristics and isolates them for benchmarking and optimization. In order to develop an evaluation criterion, it was essential to evaluate and benchmark the current state of the art for wind energy capture. A thorough history of Vertical Axis Wind Turbine (VAWT) development and technology transfer, a standardized set of VAWT ...

International Nuclear Information System (INIS)

Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) has been proposed several years ago as an approach for quantitative analysis of Laser-Induced Breakdown Spectroscopy spectra. Recently developed refinement of the spectral processing method is described in the present work. Accurate quantitative results have been demonstrated for several metallic alloys. However, the degree of accuracy that can be achieved with Calibration-Free Laser-Induced Breakdown Spectroscopy analysis of generic samples still needs to be thoroughly investigated. The authors have undertaken a systematic study of errors and biasing factors affecting the calculation in the Calibration-Free Laser-Induced Breakdown Spectroscopy spectra processing. These factors may be classified in three main groups: 1) experimental aberrations (intensity fluctuations and inaccuracy in the correction for spectral efficiency of a detection system), 2) inaccuracy in theoretical parameters used for ...

Science.gov (United States)

The critical currents of A-15 phase Nb(,3)Sn, V(,3)Si, Nb(,3)Ge, V(,3)Ga, and Nb-Sn with a few at.% Ga and Al(,2)O(,3) have been measured at temperatures up to T(,c) and in magnetic fields up to 8T to study fundamental flux pinning interactions as a function of defect size and density. The samples are electron beam evaporated films typically 2 (mu)m thick. Their particular usefulness for this study is that they span the clean to dirty limits and their normal state resistivity and grain size can be controlled by deposition parameters. The grain boundaries are the defects most responsible for flux pinning. The electron scattering mechanism is based on the local change in the coherence length due to increased conduction electron scattering and is chosen from among several possible mechanisms to calculate the elementary pinning force at a grain boundary. A direct summation of the elementary pinning force of each boundary is compared with the experimental results. ...

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... and testing of unidirectional composites, there are serious doubts about the possibility of obtaining a true ultimate compressive strength for this kind ...

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Energy Technology Data Exchange (ETDEWEB)

The method of production of xAl{sub 2}O{sub 3}-yTiO{sub 2} compositions provides for the depth distribution of coating components and specifies its mechanical properties. In case of the composition obtained by cladding, titanium is mainly concentrated at the substrate. In case of mechanical mixture or composition obtained by sintering the oxides, the depth distribution of coating components is random.

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Science.gov (United States)

... slenderness ratio. Equations which determine the ultimate compressive strength of a composite were established. Several ...

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Science.gov (United States)

... Descriptors : *PROPELLING CHARGES, *NITROCELLULOSE, *COMBUSTIBLE CARTRIDGE CASES, DENSITY, FIBERS, MANUFACTURING ...

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Science.gov (United States)

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

International Nuclear Information System (INIS)

Wood plastic composites are prepared under radiation of "6"0Co gamma source with simul, a low grade wood of Bangladesh using a water soluble monomer acrylamide (AM) mixed with a swelling solvent methanol, water or methanol/water (1:1) at different compositions in the presence of a number of additives and co-additives such as NVP (N-vinylpyrrolidone), TPGDA (tripropylene glycol diacrylate), TMPTA (trimethylol propane triacrylate), sulfuric acid, urea and copper sulfate. Polymer loading (PL) and tensile strength (TS) of the composites are measured. The role of these additives on the composites is also discussed. It is observed that nitrogen-atom containing-materials like urea, NVP and AM produce composites with the highest mechanical strength, and incorporation of copper into this system provides additional property of protection and preservation of the composites ...

International Nuclear Information System (INIS)

Polymerizing effects of high energy radiation has been found suitable for preparation of wood-polymer composites. In the present work after evaluating polymer products that have been obtained by irradiation method, wood-polymer composites have been prepared by in situ polymerization of vinyl acetate, acrylic acid and acrylic acid/styrene mixture using two samples of Iranian hardwoods, Beech and Hornbeam. These woods and their composites have been tested for their physical and mechanical properties. The results have shown that chemical bonding between polymer and the cell wall component lead to better strength properties in the composites. (author).

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Abstract not provided