Research and development for treatment and disposal technologies of TRU waste
International Nuclear Information System (INIS)
After the publication of the 2nd progress report of geological disposal of TRU waste in Japan, policy and general scheme of future study for the waste disposal in Japan was published by ANRE and JAEA. This annual report summarized aim and progress of individual problem, which was assigned into JAEA in the published policy and general scheme. The problems are as follows; characteristics of TRU waste and its geologic disposal, treatment and waste production, quality control and inspection methodology for waste, mechanical analysis of near-field, data acquisition and preparation on radionuclides migration, cementitious material transition, bentonite and rock alteration in alkaline solution, nitrate effect, performance assessment of the disposal system and decomposition of nitrate as an alternative technology. (author)
2007-04-22
Research and development on plasma facing components for fusion reactors in JAEA
International Nuclear Information System (INIS)
This paper presents the present status of R and D activities on plasma facing components for fusion reactors, such as International Thermonuclear Experimental Reactor (ITER) and fusion demonstration reactor (DEMO). The plasma facing components (PFCs) as typified by divertor and first wall components are subjected to high heat flux and particle flux from fusion plasma. It is essential for these components to have sufficient heat removal capability and robust structure against those loadings. JAEA has been carried out to develop the ITER-PFCs which consist of copper alloys and armor materials with high thermal conductivity, such as carbon fiber composites, tungsten and beryllium. The demonstration of the thermomechanical performance of the ITER-PFCs by using mock-ups has successfully been made under close mutual cooperation between the participant countries of ITER. Currently, the activity on the development of the ITER-PFCs is in a qualification phase prior to the ...
2008-10-13
Using the Am9511 arithmetic processing unit with the Motorola M6800 microprocessor
Using the Am9511 arithmetic processing unit with the Motorola M6800 microprocessor
1979-01-01
Evaluation of heterogeneity effects for Am reaction rates of the moderated subassemblies
Energy Technology Data Exchange (ETDEWEB)
The technology of minor actinide recycling in fast reactors has been discussed. In CEA, the feasibility study on Am once-through recycling in Phenix core with the moderated target subassemblies (S/As) has been performed. In this report, the evaluation of the heterogeneity effect on the moderated target S/As is described. It was evaluated by the calculation with the continuous energy Monte-Carlo code, MVP, because the accuracy of the deterministic method for the moderated target S/As is unknown. The reaction rates of four isotopes (Am-241, Am-242, Am242m and Am-243) calculated with the heterogeneous model and the homogeneous one were compared. These four isotopes play the important role in Am incineration. It is seen that the homogeneous model overestimates the reaction rates of Am-241 and Am-243 by 4 - 13%, and ...
1998-10-01
Energy Technology Data Exchange (ETDEWEB)
Ratio of the fissile isomers and prompt fissions yields has been measured in processes of neutron capture by /sup 241/Am and /sup 243/Am nuclei in the neutron energy interval from 0.2 up to 1.3 MeV. The present data and the previous results suggest that the fission Am isomers are spin structure isomers rather than shape isomers.
1984-11-01
Determination of the /sup 242m/Am nuclear moments
Energy Technology Data Exchange (ETDEWEB)
The hyperfine structure of Am atoms was investigated in an atomic beam by laser spectroscopy. The observed splittings were evaluated with respect to the magnetic dipole and electric quadrupole moments of /sup 242m/Am. The results are: ..mu../sub I/(/sup 242m/Am) = +0.97(5) nm, Q(/sup 242m/Am) = +6.5(2.0) b.
1988-07-01
Energy Technology Data Exchange (ETDEWEB)
Since actinide mononitride has several superior thermal and neutronic properties, nitride fuel is considered as a candidate for future nuclear systems, such as advanced fast reactors and accelerator-driven system. Establishing reprocessing technology is one of key technologies for the development of nitride fuel cycle. In addition to general advantages of pyrochemical process, such as the potential for economy, radiation and proliferation resistance, recycling of N-15 in nitride fuel seems to be practical in comparison with conventional hydro-process. Following the electrochemical measurements of nitride fuel in LiCl-KCl molten salt, the experimental study on closing nitride fuel cycle has been carried out in JAEA by used of TRU nitride and burnup simulated nitride samples. Recent progress of the study is summarized in this paper.
2008-08-15
Ultra-thin {sup 242m}Am fuel elements in nuclear reactors. II
Energy Technology Data Exchange (ETDEWEB)
There is growing interest in using {sup 242m}Am as a nuclear fuel for space reactors and nuclear batteries. In this paper, we discuss different {sup 242m}Am enrichments, as well as fuel weight requirements, to produce a critical reactor. It was found that relatively low enrichments of {sup 242m}Am, about 10 w/o, are enough to guarantee criticality. Such low enrichments might eliminate the need for a {sup 242m}Am enrichment process. It was also found that the best results for low {sup 242m}Am requirements are obtained with a moderator to fuel volume ratio of 10,000.
2004-04-21
Calculated neutron capture cross sections to the americium ground and isomeric states
International Nuclear Information System (INIS)
The neutron capture cross sections of "2"4"1Am and "2"4"3Am to the ground and isomeric states of "2"4"2Am and "2"4"4Am have been calculated using the Hauser-Feshbach statistical theory of nuclear reactions for energies from thermal to 2 MeV. The parameters for the calculations were obtained from recent data on ("2"4"1Am + n) and ("2"4"3Am + n) or, where necessary, from systematics of actinide nuclei. The calculated values are in good agreement with the sparse experimental data.
Energy Technology Data Exchange (ETDEWEB)
A review of fission product yields and delayed neutron data for Np-237, Pu-242, Am-242m, Am-243, Cm-243 and Cm-245 has been undertaken. Gaps in understanding and inconsistencies in existing data were identified and priority areas for further experimental, theoretical and evaluation investigation detailed. (author)
1991-07-01
International Nuclear Information System (INIS)
A review of fission product yields and delayed neutron data for Np-237, Pu-242, Am-242m, Am-243, Cm-243 and Cm-245 has been undertaken. Gaps in understanding and inconsistencies in existing data were identified and priority areas for further experimental, theoretical and evaluation investigation detailed. (author)
1990-11-06
Presentation of random process at the output of a scintillation detector
International Nuclear Information System (INIS)
(1973). USSR Ovcharenko, AM Nedavnij, OI Kapranov, BI Tomskij
Evaluation of prompt neutron spectra from fission of americium isotopes
Energy Technology Data Exchange (ETDEWEB)
Prompt neutron spectra for Am isotopes ({sup 241}Am, {sup 242m}Am, {sup 243}Am) were calculated on the basis of a modified version of the Madland-Nix model combined with multimodal fission model. The predicted spectra were found to be in fair agreement with recent data. (author)
2002-06-01
A nuclear engine design with {sup 242m}Am as a nuclear fuel
Energy Technology Data Exchange (ETDEWEB)
A preliminary design for a nuclear engine is presented. The engine is based on the nuclear heating of a gas composed of H{sub 2} and {sup 242m}Am as a nuclear fuel. This engine has an initial volume of 0.135 m{sup 3} and at 64 MPa the critical mass is 0.228 kg. The simplicity {sup 242m}Am of the engine design might compensate for the use of rare nuclear fuel, such as {sup 242m}Am.
2000-01-01
Results of Am isotopic ratio analysis in irradiated MOX fuels
Energy Technology Data Exchange (ETDEWEB)
For analysis of a small quantity of americium, it is necessary to separate from curium which has similar chemical property. As a chemical separation method for americium and curium, the oxidation of americium with pentavalent bismuth and subsequent co-precipitation of trivalent curium with BIP O{sub 4} were applied to analyze americium in irradiated MOX fuels which contained about 30wt% plutonium and 0.9wt% {sup 241}Am before irradiation and were irradiated up to 26.2GWd/t in the experimental fast reactor Joyo. The purpose of this study is to measure isotopic ratio of americium and to evaluate the change of isotopic ratio with irradiation. Following results are obtained in this study. (1) The isotopic ratio of americium ({sup 241}Am, {sup 242m}Am and {sup 243}Am) can be analyzed in the MOX fuels by isolating americium. The isotopic ratio of {sup 242m}Am and {sup ...
1997-04-01
Potential applications of /sup 242m/Am as a nuclear fuel
Energy Technology Data Exchange (ETDEWEB)
The isomer /sup 242m/Am with a half-life of 141 yr. is obtained from a (n,..gamma..) capture reaction with /sup 241/Am. The latter is a decay product of /sup 241/Pu. The isomer /sup 242m/Am has the highest known thermal fission cross section. The cross sections of this isomer are evaluated. Unit cell calculations show that nuclear systems with /sup 242m/Am require less fuel by a factor of 2 to 100 compared to conventional fuels. These results indicate that potential applications of americium fuel exist, particularly for space reactors.
1988-07-01
Biosorption of {sup 241}Am by Rhizopus arrihizus: preliminary investigation and evaluation
Energy Technology Data Exchange (ETDEWEB)
The biosorption of {sup 241}Am from solution by a fungus--Rhizopus Arrihizus (R. arrihizus), and the effect of experimental conditions on the adsorption were investigated. The preliminary results showed that the biosorption of {sup 241}Am by R. arrihizus is very efficient. An average of more than 99% of the total {sup 241}Am was removed by R. arrihizus of 1.3 g/l (dry weight) from {sup 241}Am solutions of 5.6-111 MBq/l (44.3-877.2 {mu}g/l) (C{sub 0}), with adsorption capacities (W) of 4.2-79.4 MBq/g biomass (dry weight) (33.2-627.5 {mu}g/g). The biosorption equilibrium was achieved within 1 h and the optimum pH ranged from 1 to 3. No significant differences in {sup 241}Am biosorption were observed at 10-45 deg. C, or in solutions containing Au{sup 3+} or Ag{sup +}, even 2000 times above {sup 241}Am concentration. The relationship between concentrations and ...
2002-08-01
Energy Technology Data Exchange (ETDEWEB)
Making use of a lead slowing-down spectrometer coupled to a 46 MeV electron linear accelerator and a back-to-back type double fission chamber, the fission cross sections of Am-241, Am-242m and Am-243 have been measured relative to that of U-235 from 0.1 eV to 10 keV with the energy resolution of about 40 % full width at half maximum. Each of the measured result has been compared with (1) the evaluated nuclear data in ENDF/B-VI and JENDL-3.2, and (2) the existing experimental data, for which the evaluated and the experimental data were broadened by the energy resolution function of the spectrometer. (author)
1997-12-31
Energy Technology Data Exchange (ETDEWEB)
Making use of a back-to-back type double fission chamber and a lead slowing-down spectrometer driven by a 46 MeV electron linear accelerator, the fission cross sections of Am-241, Am-242m and Am-243 have been measured relative to that of U-235 from 0.1 eV to 10 keV with the energy resolution of about 40 % full width at half maximum. Each of the measured result has been compared with (1) the evaluated nuclear data in ENDF/B-VI and JENDL-3.2, and (2) the existing experimental data, whose evaluated and measured data were broadened by the energy resolution function of the spectrometer.
1998-08-01
Energy Technology Data Exchange (ETDEWEB)
Making use of a back-to-back type double fission chamber and a lead slowing-down spectrometer driven by a 46 MeV electron linear accelerator, the fission cross sections of Am-241, Am-242m and Am-243 have been measured relative to that of U-235 from 0.1 eV to 10 keV with the energy resolution of about 40% full width at half maximum. Each of the measured result has been compared with (1) the evaluated nuclear data in ENDF/B-VI and JENDL-3.2, and (2) the existing experimental data, whose evaluated and measured data were broadened by the energy resolution function of the spectrometer. (author)
1999-02-01
Fast neutron nuclear data: Pu-239 revision and Am status
International Nuclear Information System (INIS)
Neutron cross sections for Pu-239 and Am-241, -242m, -243 have been analyzed with the aid of theoretical models. A deformed optical potential that fits total, elastic and inelastic differential cross section data and neutron strength functions for Pu-239 and Am-241 have been used. In case of Pu-239 the consistency of absolute fission data and (n, 2n) cross section is investigated. Because of the strong discrepancies in Am fission cross section data a consistent set of calculated cross section values for the chain of Am nuclei is proposed. The present state of knowledge concerning first chance fission cross section allows to analyze fission cross section data of Am-241, -242m, -243, up to 20 MeV. The results thus obtained are compared with ENDF/B-V and JENDL-3 libraries. (orig.).
International Nuclear Information System (INIS)
In the VEGA program on radionuclide release from irradiated fuel under severe accident conditions, 10 tests in total were performed at JAEA from 1999 to 2004 under inert and steam atmospheres including the highest pressure or temperature conditions. These tests showed the increase in release rate above 2,800 K or at the fuel liquefaction and the decrease in release rate under elevated pressure, which was a first observation in the world. The data on low-volatility radionuclide release, release from MOX fuel, effect of fuel oxidation, and eutectic reaction with cladding on release were obtained from the tests. The mechanism of pressure effect on release was examined and a new release model with pressure effect was proposed. In addition, the pressure effect on source term evaluation and effectiveness of accident management measures were investigated. This article summarizes the major outcomes described above that have already been published and newly describes the ...
2011-01-01
Analysis of Am-242m in solidified products
International Nuclear Information System (INIS)
When solidified products made from low-level radioactive waste with melting treatment are disposed of in near surface repositories, concentrations of the radionuclides contained in the waste package have to be evaluated. Americium-242m is one of the targeted nuclides. In this study, simple analytical methods to evaluate the activity of "2"4"2"mAm are studied. Americium, Cm and Eu in a sample solution made from simulated solidified product and tracer of "1"5"2Eu and "2"4"4Cm and unknown solution of "2"4"1"+"2"4"2"m"+"2"4"3Am were separated from matrix elements with TRU resin. The fraction containing Eu, Am and Cm was passed through pyridine resin to separate Am from Eu and Cm. The contamination factor of "2"4"4Cm/"2"4"1Am was less than 3.0x10"-"3. Curium-242 generated from "2"4"2Am was measured to evaluate the activity of "2"4"2"mAm. The ...
2006-10-01
UK PubMed Central (United Kingdom)
The safety, pharmacokinetics, and distribution in tissue of an amphotericin B (AmB)-cholesteryl sulfate colloidal dispersion (ABCD) were compared with those of micellar amphotericin B-deoxycholate (m-AmB)....Full Text Available
1992-02-01
International Nuclear Information System (INIS)
Determination of americium (Am) is one of the requirements of chemical quality assurance of plutonium (Pu) bearing fuel materials. Though many methods are published for determining Am at picogram to femtogram levels in environmental and biological matrices, yet a few of them are used routinely for Pu based nuclear fuel samples. This paper gives a brief summary of the different analytical methods available and presents results of our experiments on the determination of Am in Pu bearing fuels using gamma spectroscopy. The methods utilizing gamma emissions from "2"4"1Am and Pu isotopes are fast as they do not involve chemical separation of Pu and Am, do not require an accurate knowledge of the efficiency values of the detector systems and are not dependent on the availability of a radiometric standard for "2"4"1Am. In addition, for aged Pu samples containing large ...
2010-11-15
Transmutation of {sup 241}Am in a high thermal neutron flux
Amongst the minor actinides issued from the spent nuclear fuel, {sup 241}Am is present in high concentration and contributes significantly to the long-term radiotoxicity of nuclear waste. A major uncertainty was present in the transmutation chain of {sup 241}Am when irradiated by a high intensity thermal neutron flux. This uncertainty was brought about by the poor knowledge of the {sup 242gs}Am neutron capture cross section. A dedicated experiment has been performed at the Institut Laue-Langevin in Grenoble, which gives a definitive experimental answer to this problem.
1998-10-26
Transmutation of "2"4"1Am in a high thermal neutron flux
International Nuclear Information System (INIS)
Amongst the minor actinides issued from the spent nuclear fuel, "2"4"1Am is present in high concentration and contributes significantly to the long-term radiotoxicity of nuclear waste. A major uncertainty was present in the transmutation chain of "2"4"1Am when irradiated by a high intensity thermal neutron flux. This uncertainty was brought about by the poor knowledge of the "2"4"2"g"sAm neutron capture cross section. A dedicated experiment has been performed at the Institut Laue-Langevin in Grenoble, which gives a definitive experimental answer to this problem.
1998-10-26
Measuring relative probability of Am-242 #beta#-decay
International Nuclear Information System (INIS)
... americium 241 americium 242 beta decay chain reactions integral doses mass
... reverse aeb 9 nescesmsy amI identify by block number) Provides procedures for evaluating metal, consumable, and combustible cartridge cases. ...
1980-10-21
AM: An Artificial Intelligence Approach to Discovery in ...
... For example, contrast solving the Missionaries and Cannibals problem with the more ill-defined reasoning which led to inventing it. ...
1976-07-01
Evidence for long-lived isomeric states in neutron-deficient /sup 236/Am and /sup 236/Bk nuclei
Energy Technology Data Exchange (ETDEWEB)
A 5.76 MeV alpha-particle group has been observed in Am and Bk sources separated from a CERN W target. The data are interpreted due to the production of long-lived isomeric states in /sup 236/Am and /sup 236/Bk which decay to /sup 236/Pu. The possibility of high spin states as well as of shape isomeric states is raised.
1987-06-04
Accelerator mass spectrometry: state of the art
Energy Technology Data Exchange (ETDEWEB)
Accelerator Mass Spectrometry (AMS) is the analytical technique of choice for the detection of long-lived radionuclides which cannot be practically analysed with decay counting or conventional mass spectrometry. The main use of AMS has been in the analysis of radiocarbon and other cosmogenic radionuclides for archaeological, geological and environmental applications. In addition, AMS has been recently applied in biomedicine to study exposure of human tissues to chemicals and biomolecules at attomole levels. There is also a world-wide effort to analyse rare nuclides of heavier masses, such as long-lived actinides, with important applications in safeguards and nuclear waste disposal. The use of AMS is limited by the expensive accelerator technology required and there are several attempts to develop smaller and cheaper AMS spectrometers. 5 refs.
1996-12-31
Incineration of {sup 241}Am induced by thermal neutrons
Energy Technology Data Exchange (ETDEWEB)
An experimental study of the {sup 241}Am incineration in a high-intensity thermal neutron flux was carried out at the high-flux reactor of the Institut Laue-Langevin in Grenoble. The combination of nuclear {gamma}-ray spectroscopy and off-line mass spectrometry methods made possible the measurement of several parameters of the transmutation chain and the first experimental determination of the unknown {sup 242gs}Am thermal neutron capture cross section, which plays an essential role in the {sup 241}Am incineration process. During a 19 days irradiation in a thermal neutron flux of 5.6x10{sup 14} n/(s cm{sup 2}), (46{+-}5)% of the initial {sup 241}Am was transmuted by neutron capture of which (22{+-}8)% was incinerated by nuclear fission. A value of the thermal neutron cross section of {sup 242gs}Am(n,{gamma}) of (330{+-}50) barns was obtained. We show that this keeps the option open ...
2001-10-22
Radiochemical determination of neutron capture cross sections of {sup 241}Am
Energy Technology Data Exchange (ETDEWEB)
The thermal neutron capture cross sections and the neutron capture resonance integrals of {sup 241}Am leading to the production of the isomer {sup 242m}Am and the ground-state {sup 242g}Am were measured radiochemically by the Cd-ratio technique with neutron flux monitors of Co/Al and Au/Al alloy. Highly-purified {sup 241}Am targets were irradiated in an aluminum capsule by using JMTR. The neutron fluxes and their epithermal neutron fractions were determined by measuring {gamma}-rays of {sup 60}Co and {sup 198}Au. The yields of {sup 242m}Am and {sup 242g}Am were decided by analyzing growth and decay curves of the {alpha}-ray activity ratios {sup 242}Cm/{sup 241}Am. The resultant thermal neutron capture cross sections are 85.7 {+-} 6.3 b and 768 {+-} 58 b for {sup 242m}Am and {sup 242g}Am, and the ...
1997-07-01
Re-evaluation of neutron nuclear data for {sup 242m}Am, {sup 243}Am, {sup 99}Tc and{sup 140}Ce
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)
2002-12-01
Energy Technology Data Exchange (ETDEWEB)
Evaluation of nuclear data has been performed for {sup 237}Np, {sup 241}Am, {sup 242g}Am and {sup 242m}Am. Neutron data were obtained at energies from 20 to 250 MeV and combined with JENDL-3.3 data at 20 MeV. Evaluation of the proton data has been done from 1 to 250 MeV. The coupled channel optical model was used to obtain angular distributions for elastic and inelastic scattering and transmission coefficients. Pre-equilibrium exciton model and Hauser-Feshbach statistical model were used to describe neutron and charged particles emission from excited nuclei. These evaluation is the first work for producing full sets of evaluated file up to 250 MeV for {sup 237}Np and Americium isotopes. (author)
2002-12-01
Evaluation of nuclear data has been performed for sup 2 sup 3 sup 7 Np, sup 2 sup 4 sup 1 Am, sup 2 sup 4 sup 2 sup g Am and sup 2 sup 4 sup 2 sup m Am. Neutron data were obtained at energies from 20 to 250 MeV and combined with JENDL-3.3 data at 20 MeV. Evaluation of the proton data has been done from 1 to 250 MeV. The coupled channel optical model was used to obtain angular distributions for elastic and inelastic scattering and transmission coefficients. Pre-equilibrium exciton model and Hauser-Feshbach statistical model were used to describe neutron and charged particles emission from excited nuclei. These evaluation is the first work for producing full sets of evaluated file up to 250 MeV for sup 2 sup 3 sup 7 Np and Americium isotopes.
2002-01-01
Total and spontaneous fission half-lives of the americium and curium nuclides
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.
1984-01-01
Total and spontaneous fission half-lives of the americium and curium nuclides
International Nuclear Information System (INIS)
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 "2"4"1Am, "2"4"2Am, "2"4"3Am, "2"4"2Cm, "2"4"3Cm, "2"4"4Cm, "2"4"5Cm, "2"4"6Cm, "2"4"7Cm, "2"4"8Cm, and "2"5"0Cm. The uncertainties are provided at the 95% confidence limit for each of the recommended values. (author).
1985-06-01
The differential cross section measurements for /sup 241/Am, /sup 242m/Am and /sup 243/Am are reviewed in the energy range from 0.5 eV to 10 keV. Parameters extracted from resonance analysis, such as the neutron strength function, the average level spacing, the average capture and fission widths, are compared for the various measurements. The average capture and fission cross sections from 100 eV to 10 keV are directly compared. The status of the data set is discussed with suggestions for further measurements. 24 references.
1978-11-16
Primary standardization of {sup 242} Am radioactive sources
Energy Technology Data Exchange (ETDEWEB)
The procedure followed by the Laboratorio de Metrologia Nuclear in Sao Paulo, Brazil, for the standardization of {sup 242g} Am is described. The calibration system was composed of a 4 {pi} gas-flow proportional counter coupled to a pair of NaI(Tl) crystals operating in coincidence. The samples were produced by irradiating dried aliquots of {sup 241} Am with thermal and epithermal neutrons at the IEA-R1 research reactor. The efficiency tracer technique has been applied using {sup 60} Co as tracer. The beta detection efficiency was changed by external absorbers and extrapolated to unity by linear least square fitting applying covariance methodology. (author)
2001-07-01
Fission neutron multiplicity for the /sup 242m/Am(n,f) reaction
International Nuclear Information System (INIS)
This paper analyzes fission neutron multiplicity for the /sup 242m/Am(n,f) reaction. The fission neutron multiplicity, v bar, of /sup 242m/Am(n,f) was measured relative to that of /sup 235/U(n,f) using the neutron time-of-flight facility at the Lawrence Livermore National Laboratory 100-MeV electron Linac. A comparison of the measured energy dependence of v-bar is made with semi-empirical models of neutron emission from the actinides. 22 refs.
Evaluation of prompt neutron spectra for americium isotopes by multimodal Madland-Nix model
Energy Technology Data Exchange (ETDEWEB)
The prompt neutron spectra of {sup 241}Am, {sup 242m}Am, and {sup 243}Am were evaluated for the next version of Japanese Evaluated Nuclear Data Library, using the methodology developed by the authors. The method is based on the Madland-Nix theory with some improvements to consider the multimodal nature of the fission process, and shell effects on the level density parameters and the neutron multiplicity from light and heavy fragments. The results were compared with previous evaluations. (authors)
2008-07-01
American National Standard: for nuclear criticality control of special actinide elements
Energy Technology Data Exchange (ETDEWEB)
This standard is applicable to operations with the following: /sup 237/Np, /sup 238/Pu, /sup 240/Pu, /sup 241/Pu, /sup 242/Pu, /sup 241/Am, /sup 242m/Am, /sup 243/Am, /sup 243/Cm, /sup 244/Cm, /sup 245/Cm, /sup 247/Cm, /sup 249/Cf and /sup 251/Cf. Subcritical mass limits are presented for isolated fissionable units. The limits are not applicable to interacting units.
1981-01-01
The SUERC AMS laboratory after 3 years
British Library Electronic Table of Contents (United Kingdom)
The new SUERC AMS Laboratory was described at AMS-9. Since then there have been technological developments, added and improved analysis capability, the formation of additional complementary groups, the purchase of another instrument, and many samples measured. Be, C, Al, Cl, Ca and I-AMS are established with measured species changing weekly. Full-terminal potential running is now routine and 5MV is proving sufficient for all species. Ion detection and evaluation has also been improved by the use of even thinner detector windows as necessary and a more powerful on-line data analysis system. Routine radiocarbon measurement is to 4permil reproducibility at middling current and graphite samples of as little as 100mg C can be accommodated. Even smaller samples can be measured as CO2 using He ca...
2007-01-01
Strain Rate Effects on Ultimate Strain of Copper
... Figure 3a. PETN Filled Tube Specimen Detonated by Exploding Bridgewire Specimen POLYETIILLENE END-CAP "1- 901am WALL IHICKNESS ...
1979-05-01
Regulation of Glutamate Dehydrogenases in nit-2 and am Mutants of Neurospora crassa
UK PubMed Central (United Kingdom)
The regulation of the glutamate dehydrogenases was investigated in wild-type Neurospora crassa and two classes of mutants altered in the assimilation of inorganic nitrogen, as either...Full Text Available
1979-03-01
Microstructures of friction welded joints of AZ31 to AM60 magnesium alloys
Energy Technology Data Exchange (ETDEWEB)
AZ31 magnesium alloy was friction-welded to AM60 and the microstructures and the friction welding process were studied. The microstructures changed near the weld interface. The AZ31 was refined to a grain size of several {mu}m near the weld interface. The nucleation occurred in the shear bands that were introduced during the welding process. On the other hand, the eutectic structure was deformed and the lamellar structure which was composed of {alpha}-Mg and Mg{sub 17}Al{sub 12} was formed near the weld interface in AM60 alloy. In the friction process, the adhesion and peel off occurred alternately between AZ31 and AM60. Eventually, bonding was completed during upset process. (orig.)
2003-07-01
... an endocrinologist here and am part of the Diabetes and Endocrinology Associates here at Shawnee Mission Medical ... also an endocrinologist and a member of the Diabetes and Endocrinology Associates here at Shawnee Mission Medical ...
Golden coast on the Black Sea; Goldkueste am Schwarzen Meer
Energy Technology Data Exchange (ETDEWEB)
The most profitable terrain in Romania is already sold. Investors are now looking for new wind power sites. The contribution presents details. (orig.)
2007-06-15
International Nuclear Information System (INIS)
English 2000 p. 91 Brazil Saiki, M. Kamiya, AM Nomura, DH Mateus,
BBC - Ethical Man blog: Think before you carve
... And I am sure lots of us carnivores would be a lot less keen on our mixed grills if we had to look ...
At the Root of the Wood Wide Web
UK PubMed Central (United Kingdom)
Arbuscular mycorrhizal (AM) fungi are mutualistic symbionts living in the roots of 80% of land plant species, and developing extensive, below-ground extraradical hyphae fundamental for the uptake of...Full Text Available
2006-01-01
UK PubMed Central (United Kingdom)
The mutualistic interaction of plants with arbuscular mycorrhizal (AM) fungi is characterized by an exchange of nutrients. The plant provides sugars in the form of hexoses to the heterotrophic fungus...Full Text Available
2008-05-01
This report summarizes the results of an expert-opinion elicitation activity designed to qualitatively assess the status and capabilities of currently available computer codes and models for accident analysis and reactor safety calculations of advanced sodium fast reactors, and identify important gaps. The twelve-member panel consisted of representatives from five U.S. National Laboratories (SNL, ANL, INL, ORNL, and BNL), the University of Wisconsin, the KAERI, the JAEA, and the CEA. The major portion of this elicitation activity occurred during a two-day meeting held on Aug. 10-11, 2010 at Argonne National Laboratory. There were two primary objectives of this work: (1) Identify computer codes currently available for SFR accident analysis and reactor safety calculations; and (2) Assess the status and capability of current US computer codes to adequately model the required accident scenarios and associated phenomena, and identify important gaps. During the review, ...
2011-06-01
Energy Technology Data Exchange (ETDEWEB)
The aims of the work described here were to provide an experimental basis for evaluating the committed effective dose equivalent per unit intake together with the ALI for four industrial oxide bearing dusts, and to assess the extent to which {sup 241}Am could be used for estimating the {sup 239}Pu content of the lung after an accidental intake of these materials. (author).
1991-01-01
Energy Technology Data Exchange (ETDEWEB)
A technique for measurement of the energy spectra of fission fragments is discussed. The fine structure found in the spectra of fragments from spontaneous fission of {sup 242}Cm and fast-neutron fission of {sup 242{ital m}}Am is analyzed. The quantitative parameters of the structure and their analogy with the characteristics of cold fission are discussed.
1989-05-01
Smart Takes - Archive: April 2011 | SmartPlanet
... April 29, 2011, 8:25 AM PDT | By Andrew Nusca Ottawa taps Itron for 210,000 smart water meters The City of Ottawa has chosen smart grid firm Itron ...to deploy smart water meters and related infrastructure in town. April 29, 2011, 7:18 AM PDT | By Andrew ...
Mass-energy spectra of fission fragments in the reaction {sup 242m}Am(n{sub th},f)
Energy Technology Data Exchange (ETDEWEB)
The mass-energy spectra of the fragments of thermal fission of {sup 242m}Am are measured using the time-of-flight technique. The resulting mass-yield curve and peak-to-valley ratio agree with radiochemical data. The parameters of the kinetic energy distribution of the fragments are determined for the first time. Data on the fine structure of mass spectra in the region of cold fragmentation are presented. 15 refs., 4 figs.
1994-12-01
The mz8310 device support module provides support for the following record types: event, pulseCounter, pulseDelay, and pulseTrain. No driver support is needed. Up to 4 mz8310 modules are supported. Each 8310 module contains 10 channels, which are identified as signals O,...9. Each channel is individually configurable. Each mz83 10 has two Am9513 Timing Controller chips. Each Am9513 has 5 counters.
1992-07-09
Enabling Technologies for Petascale Electromagnetic Accelerator Simulation
Energy Technology Data Exchange (ETDEWEB)
The SciDAC2 accelerator project at SLAC aims to simulate an entire three-cryomodule radio frequency (RF) unit of the International Linear Collider (ILC) main Linac. Petascale computing resources supported by advances in Applied Mathematics (AM) and Computer Science (CS) and INCITE Program are essential to enable such very large-scale electromagnetic accelerator simulations required by the ILC Global Design Effort. This poster presents the recent advances and achievements in the areas of CS/AM through collaborations.
2007-11-09
UK PubMed Central (United Kingdom)
The oceanic bathypelagic realm (1000–4000Ȁa;m) is a nutrient-poor habitat. Most fishes living there have pelagic larvae using the rich waters of the upper 200Ȁa;m. Morphological...Full Text Available
2009-04-23
Biosorption of Americium-242 by saccharomyces cerevisiae: preliminary evaluation and mechanism
International Nuclear Information System (INIS)
As an important radioisotope in nuclear industry and other fields, americium-241 is one of the most serious contamination concerns duo to its high radiation toxicity and long half-life. In this experiment, the biosorption of "2"4"1Am from solution by a fungus, Saccharomyces cerevisiae (S. cerevisiae), and the effects of various experimental conditions on the biosorption and the mechanism were explored. The preliminary results showed that S. cerevisiae is a very efficient biosorbent. An average of more than 99% of the total "2"4"1Am could be removed by S. cerevisiae of 2.1g/L (dry weight) from "2"4"1Am solutions of 2.22MBq/L -555 MBq/L (Co). The adsorption equilibrium was achieved within 1 hour and the optimum pH ranged 1-3. The culture times of more than 16 hours were suitable and the efficient adsorption of 241Am by the S. cerevisiae could be noted. The biosorption of 241Am by the ...
Energy Technology Data Exchange (ETDEWEB)
The author cites the example of Gelsenkirchen in order to illustrate the measures taken in the field of power supply with regard to air pollution abatement. (orig.) [Deutsch] Der Verfasser gibt am Beispiel der Stadt Gelsenkirchen einen Ueberblick darueber, was hinsichtlich des Klimaschutzes - und zwar bezogen auf die Energieversorgung - in den letzten Jahren in Gelsenkirchen getan wurde. (orig.)
1996-07-01
Ultra-thin {sup 242m}Am fuel elements in nuclear reactors
Energy Technology Data Exchange (ETDEWEB)
There is a growing interest in using {sup 242m}Am as a nuclear fuel. The advantages of {sup 242m}Am as a nuclear fuel derive from the fact that {sup 242m}Am has the highest thermal fission cross section. The thermal capture cross section is relatively low and the number of neutrons per thermal fission is high. These nuclear properties make it possible to obtain nuclear criticality with ultra-thin fuel elements. The possibility of having ultra-thin fuel elements enables the use of these fission products directly, without the necessity of converting their energy to heat, as is done in conventional reactors. There are three options of using such highly energetic and highly ionized fission products. - Using the fission products themselves for ionic propulsion. - Using the fission products in an MHD generator, in order to obtain electricity directly. - Using the fission products to heat a gas up to a high temperature for ...
2000-12-01
Thermal-neutron capture cross section and resonance integral of americium-241
International Nuclear Information System (INIS)
The thermal-neutron capture cross section (#sigma#_0_,_g) and the resonance integral (I_0_,_g) leading to the ground state of "2"4"2Am were measured by an activation method for neutron capture by "2"4"1Am. A method with gadolinium, which was similar to the cadmium difference method, was used to measure the cross section #sigma#_0_,_g with attention to resonances of "2"4"1Am. Americium chloride samples containing "2"4"1Am radioisotope were irradiated for 68 h in the long-irradiation plug of the Kyoto University Research Reactor, KUR. Wires of Co/Al and Au/Al alloys were used as monitors to determine thermal-neutron fluxes and epithermal Westcott's indexes at the irradiation positions. An #alpha#-ray spectrometer was used to measure the activity ratios of "2"4"2Cm to "2"4"1Am. On the basis of Westcott's convention, the #sigma#_0_,_g and I_0_,_g values were determined as 628#+-#22 b ...
2007-12-01
Review of integral data on higher transactinides
International Nuclear Information System (INIS)
A review of the status of integral measurements is presented for "2"4"0Pu, "2"4"1Pu, "2"4"2Pu, "2"4"1Am and "2"4"3Am. This review includes integral measurements pertinent to thermal reactor systems, i.e., thermal cross sections and resonance integrals, as well as measurements for fast reactor systems. It appears that for these nuclides the data for thermal reactors are in good shape; however, more work is recommended in defining the branching ratio of the capture cross section of "2"4"1Am to the isomeric and ground states of "2"4"2Am. Also, benchmark irradiation data are needed for cross section data testing using depletion/production codes. For fast reactors, experiments are in progress, in the UK, in France, and also in the US, with partial results available at this time. Fast integral data obtained from these measurements will be very beneficial. The recommendation pertaining to ...
1979-05-01
International Nuclear Information System (INIS)
Extraction of copper-, nickel-, zinc- and cadmium complexes with 4-(2 pyridilazo)-resorcin (PAR) is studied in the presence of 2-aminopyridine (Am). Maximum optical densities of the extracts are attained at pH=7.5-8.0; 6.0-7.0; 6.5-7.0 and 7.0-8.0, respectively. The ratio of components in the complexes extractable by chloroform was defined by the method of isomolar series and equilibrium shift. It is established that nickel and copper are extracted to the organic phase as the NiAm(PAR)_2 and CuAmPAR complexes, and, in the case of zinc and cadmium, complexes of different composition are extracted, for example Zn(Am)_2PAR and ZnAm(PAR)_2. The light absorption spectra are studied and molar extinction coefficients of complex extracts are determined at lambdasub(max). It is shown that the general low of light absorption is observed within a sufficiently wide range of concentrations for ...
1984-01-01
Energy Technology Data Exchange (ETDEWEB)
Yet designed to measure charged component of the cosmic rays, the foreseen Alpha Magnetic Spectrometer (AMS-02) could also release {gamma}-ray studies, in the energy range from GeV to TeV, using the tracker system, for {gamma}-rays converted in e{sup +}e{sup -} pair, and the electromagnetic calorimeter. In the first part of the thesis are described the calibrations and the performances of the engineering model of the calorimeter, obtained from the analysis of data taken during a test-beam performed at CERN in July 2002. In the second part of the thesis, the AMS-02 discovery potential for {gamma}-astrophysics is presented. While exposure maps of the {gamma}--sky are computed for one year of data taking with the {gamma}--detectors, the acceptance of the calorimeter is obtained from Monte-Carlo simulations. The AMS-02 potential is then estimated for signals from the Vela pulsar and for some supersymmetric signals from the ...
2004-12-15
ZZ UKFY2, Fission Yields of Th, U, Np, Pu, Am, Cm, Cf Isotopes
International Nuclear Information System (INIS)
Description of program or function: Format: ENDFB-6 format; Nuclides: Th-232, U-233, U-234, U-235, U-236, U-238, Np-237, Np-238, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241, Am-242, Am-243, Cm-243, Cm-244, Cm-245, and from the spontaneous fission of Cm-242, Cm-244, and Cf-252. Origin: New evaluation (Crouch 1, 2, 3, 4; UKFY1; JEF-1). A new evaluation of fission product yields from the thermal, fast, and 14 MeV neutron-induced fission of the following nuclides has been prepared in ENDFB-VI format: "2"3"2Th, "2"3"3U, "2"3"4U, "2"3"5U, "2"3"6U, "2"3"8U, "2"3"7Np, "2"3"8Np, "2"3"8Pu, "2"3"9Pu, "2"4"0Pu, "2"4"1Pu, "2"4"2Pu, "2"4"1Am, "2"4"2"mAm, "2"4"3Am, "2"4"3Cm, "2"4"4Cm, "2"4"5Cm; and from the spontaneous fission of "2"4"2Cm, "2"4"4Cm, and "2"5"2Cf
Biosorption of americium-241 by Candida sp.
Energy Technology Data Exchange (ETDEWEB)
As an important radioisotope in nuclear industry and other fields, americium-241 is one of the most serious contamination concerns duo to its high toxicity and long half-life. In this experiment, the biosorption of {sup 241}Am from solution by Candida sp., and the effects of various experimental conditions on the adsorption were investigated. The preliminary results showed that the adsorption of {sup 241}Am by Candida sp. was efficient. {sup 241}Am could be removed by Candida sp. of 0.82 g/L (dry weight) from {sup 241}Am solutions of 5.6-111 MBq/L (44.3-877.2 {mu}g/L)(C{sub 0}), with maximum adsorption rate (R) of 98% and maximum adsorption capacities (W) of 63.5 MBq/g biomass (dry weight) (501.8 {mu}g/g). The biosorption equilibrium was achieved within 4 hour and the optimum pH was pH = 2. No significant differences on {sup 241}Am adsorption were observed at 10 C-45 C, or in ...
2003-07-01
XML schema for atomic and molecular data. Summary report of consultants' meeting
International Nuclear Information System (INIS)
Advanced developments in computer technologies offer exciting opportunities for new distribution tools and applications in various fields of physics. The convenient and reliable exchange of data is clearly an important component of such applications. Therefore, in 2003, the A+M Data Unit initiated within the collaborative efforts of the DCN (Data Centre Network) a new standard for atomic, molecular and particle surface interaction data exchange (AM'PSI) based on XML (eXtensible Markup Language). A working group composed of staff from the IAEA, NIST, ORNL and Observatoire Paris-Meudon meets biannually to discuss progress made on the XML schema, and to foresee new developments and actions to be taken to promote this standard for AM/PSI data exchange. (author)
2007-12-06
Vacuum distillation refining and recycling of magnesium alloys
Energy Technology Data Exchange (ETDEWEB)
Purification parameters of the vacuum distillation process for AM50A and AZ31B magnesium alloy were studied. The vacuum distillation tests were kept at 580 C to 620 C up to 10 h under a vacuum pressure of about 1 Pa. The purification ratio for AM50A magnesium alloy increases with increasing the purification time. The chemical compositions of materials deposited purifying at 580 C for AM50A magnesium alloy almost satisfy the values for pure magnesium specified by JIS standard specification. The chemical compositions of deposited materials at 600 C for AZ31B magnesium alloy satisfy the values specified by the standard specification except for Zn. (orig.)
2003-07-01
The Brazilian Bragg curve detector built for AMS studies
Energy Technology Data Exchange (ETDEWEB)
A Bragg curve detector (BCD) has been designed and built to be used for AMS purposes. Its design is described and its performance, obtained in tests at the Australian National University (ANU), is reported. At a {sup 36}Cl energy of 154 MeV, the energy resolution was found to be 0.38%, and the charge resolution 1.3%. The {sup 36}Cl and {sup 36}S are completely discriminated. Good separation was also achieved at 64 MeV, and a measurement at this energy of the {sup 36}Cl/Cl ratio of a sample measured previously at 154 MeV with the standard ANU ionization detector agreed well with the earlier value. This very simple detector has been shown to be suitable for use in AMS programs.
2000-10-01
THERMAL-NEUTRON FISSION CROSS SECTIONS FOR ISOTOPES OF PLUTONIUM, AMERICIUM, AND CURIUM
The following thermal-neutron fission cross sections have been measured in the thermal column of the Materials "Testing Reactor at Idaho Falls, Idaho: Pu/ sup 238/, 18.4 plus or minus 0.9 b; Am/sup 241/, 3.13 plus or minus 0.15 b; Am/sup 245/, 6390 plus or minus 500 b; Am/sup 243/, <0.072 b Cm/sup 243/, 690 plus or minus 50 b; Cm/sup 245/, 1880 plus or minus 150 b. In addition, a pile neutron capture cross section of 520 plus or minus 40 b has been measured for Pu/sup 238/. (auth)
1957-09-01
British Library Electronic Table of Contents (United Kingdom)
This study describes the chemical composition of the essential oil of Artemisia maritima (Am.Oil) and the pharmacological basis for its medicinal use in gut and airways disorders. Twenty five compounds, composing 93.7% of the oil, were identified; among these, chrysanthenyl propionate and elixene were identified for the first time from any Artemisia species. The Am.Oil (0.3?1.0 mg/mL) suppressed spontaneous and high K+ (80 mM)-induced contractions in isolated rabbit jejunum, suggestive of an antispasmodic effect mediated possibly through calcium channel blockade. The calcium channel blockade activity was confirmed when pre-treatment of the tissue with Am.Oil (0.01?0.03 mg/mL) shifted the Ca++ concentration-response curves to the right, similar to verapamil and papaverine. In isolated trach...
2011-01-01
Studies on heterogeneous simulated Am targets. Influence of lanthanide oxides
Energy Technology Data Exchange (ETDEWEB)
Targets for heterogeneous transmutation of americium are composed of a support material, the inert matrix and of an americium oxide compound: AmO{sub 2-x} or Am{sub 2}O{sub 3}. In parallel to the studies using americium, simulated compounds of americium oxide, chosen amongst lanthanide oxides, are used. The selection of these compounds is based on theoretical, physical and crystallochemical considerations. In order to assess the influence of impurities composed of lanthanide oxides, resulting from the separation process, on the physical and chemical properties of such a target, synthesis of oxide powders containing impurities associated with the simulated americium oxide, characterizations, crystallographic studies and sodium compatibility tests have been performed. (author)
1997-12-31
Potential of AMS for Quantifying Long-Lived Reaction Products
International Nuclear Information System (INIS)
Accelerator mass spectrometry (AMS) represents a powerful technique for the detection of long-lived radionuclides through ultra-low isotope ratio measurements. In many cases, counting atoms rather than decays yields much higher sensitivities. The potential of AMS will be demonstrated on typical radionuclides of interest with half-lives between some tens of years up to a hundred million years. The precise measurement of the 27Al(n,2n)26Al excitation function will be exemplified. Lack of information exists for a list of nuclides as pointed out by nuclear data requests. A brief overview on detection limits and some applications for selected long-lived radionuclides is given.
2005-05-24
British Library Electronic Table of Contents (United Kingdom)
Abstract Introduction.- Infection is the worst complication seen with inflatable penile prosthesis (IPP). Both the American Medical Systems (AMS) and Coloplast IPP have infection retardant coatings. AMS is coated at the factory with rifampicin and minocycline (InhibiZone). The Coloplast IPP has a hydrophilic coating covalently bonded to its components that will absorb any aqueous solution before implantation and provides increased surface lubricity to decrease bacterial adherence. Aim.- We tested several antibiotic dips comparing zones of inhibition (ZOI) against five commonly infecting bacteria with coated Coloplast implants. Results were compared with those ZOI created with strips of an AMS IPP precoated with InhibiZone. Methods.- Pieces of sterile Coloplast Titan IPP were dipped in (i) ...
2011-01-01
Adsorption and Dissociation of Molecular Hydrogen on the (0001) Surface of DHCP Americium
Hydrogen molecule adsorption on the (0001) surface of double hexagonal closed packed americium has been studied in detail within the framework of density functional theory. Weak molecular hydrogen adsorptions were observed. The most stable configuration corresponded to a Hor2 approach molecular adsorption at the one-fold top site where the molecule's approach is perpendicular to a lattice vector. Adsorption energies and adsorption geometries for different adsorption sites will be discussed. The change in work functions, magnetic moments, partial charges inside muffin-tins, difference charge density distributions and density of states for the bare Am slab and the Am slab after adsorption of the hydrogen molecule will be discussed. Reaction barrier for the dissociation of hydrogen molecule will be presented. The implications of adsorption on Am 5f electron localization-delocalization will be summarized.
2009-03-01
International Nuclear Information System (INIS)
Full text of publication follows: Radiation hardening and embrittlement due to high-energy neutron radiation around 623 K are the important issues on reduced-activation ferritic/martensitic (RAF/M) steels. It is expected that the improvement of radiation hardening might be one of effective ways to control the mechanical properties of RAF/M after irradiation. It has been reported that the weld joint has less hardening than the base metal from the tensile test results of TIG weldments irradiated in HFIR. This report indicated that radiation hardening can be reduced by the optimization of heat treatment condition for F82H. The purposes of this study are to establish the condition of heat treatment for minimum of radiation hardening in F82H steel using Neutron/Ion-irradiation and to examine a correlation between tensile property and micro-hardness before/after irradiation. The materials used in this study were F82H IEA heat and F82H heat treatment variants. Neutron irradiation was ...
2007-12-10
Use of Microelectrode Arrays to Directly Measure Diffusion of ...
... F.; Murray, R. W. J. Am. Chem. ... 14. Thackeray, J. W.; White, H. S.; Wrighton, M. SJ Phys. ... Dr. James S. Murday (1) Dr. Harold H. Singerman (i) ...
1990-05-16
UK PubMed Central (United Kingdom)
During the symbiotic interaction between Medicago truncatula and the arbuscular mycorrhizal (AM) fungus Glomus intraradices, an endogenous increase in jasmonic acid...Full Text Available
2005-11-01
SUBMIT TO: AM105 CONFERENCE TITLE: Earth Observing Systems VI - NASA
BAE SYSTEMS Infrared Imaging Systems. MS 209. 2 Forbes Road. Lexington, MA 02421 -7306. (781) 863-3762. (781) 863-4809 (fax) ken.overoye @lmco.com ...
Resonance ionization spectroscopy at {sup 240f,242f}Am fission isomers
Energy Technology Data Exchange (ETDEWEB)
Optical Isotope shift measurements have been performed for the {sup 240f,242f}Am fission isomers to test the stability of nuclear deformation as function of the neutron number. The method is based on resonance ionization spectroscopy (RIS) in a buffer gas cell with fission detection of the ionization process. The {sup 240f,242f}Am fission isomers have been produced by {sup 242}Pu(p, 3n), {sup 242}Pu(d, 2n) reactions, respectively. Relative isotope shift ratios X{sub exp}{sup 242f}(500 nm)=IS{sup 242f,241}/IS{sup 243,241}=41.4(8) and X{sub exp}{sup 240f}(500 nm)=IS{sup 240f,241}/IS{sup 243,241}=39.2(8) were measured. From these ratios a small difference {delta}{beta}{sub 2}{sup 242f,240f}=0.0076(14) of the deformation parameter {beta}{sub 2} can be deduced assuming that the isotope shift between the reference isotopes {sup 241,243}Am is caused by a pure volume change. (orig.)
1997-10-01
Energy Technology Data Exchange (ETDEWEB)
The authors introduce the above electric car. They deal particularly with the vehicle concept, the energy consumption and the emission balance. (orig.).
1992-05-04
Performance of the AMS-02 Experiment for High Energy Gamma Ray Astrophysics
AMS is a particle detector designed to perform high precision measurements of the cosmic rays fluxes with the main goals of searching for anti-nuclei, as remnants of primordial anti-matter, and of measuring the faintest components of the cosmic flux, anti- protons, positrons and high energy photons. To fulfill the requirements of large acceptance, long exposure time and excellent particle identification needed to achieve the intended results, AMS will operate in space as an attached payload to the International Space Station (ISS), being the first full featured particle physics experiment to operate in the Earth orbit. The AMS-02 accurate measurements of cosmic-ray nuclei, protons, antiprotons, electrons and positrons will be completed by high energy gamma rays detection. The experiment will detect gamma-rays, either by reconstructing e+e? pairs generated by photons converted upstream the tracker (conversion mode), or based ...
2007-01-01
Panel > Cloudenomics 101 What Cloud Computing Really Means for
Aug 8, 2011 ... Panel > Cloudenomics 101 What Cloud Computing Really Means for NASA. 11:00 am in Collaboration, LiveCall by Lucas Cioffi (Moderator) ...
How much donated leave can I receive? - NSSC Information Center - NASA
Oct 28, 2009 ... Note: FERS employees become eligible for disability retirement after 18 ... Can I use advanced sick leave while I am on the Voluntary Leave ...
Expression of Fc receptors is suppressed in alveolar macrophages from patients with sarcoidosis.
UK PubMed Central (United Kingdom)
To study the expression of Fc receptors in human alveolar macrophages (AM), the cells were collected from 12 healthy controls and 22 patients with sarcoidosis and the activity involved in binding to...Full Text Available
1988-09-01
Curium isotopes and americium-242 m in Irish Sea sediment
Energy Technology Data Exchange (ETDEWEB)
An intertidal estuarine sediment core was collected from Esk Estuary in the Irish Sea which had been contaminated by low-level radioactive liquid effluent from the nuclear fuel reprocessing plants at Sellafield, UK. The {sup 242}Cm and {sup 243,244}Cm radioactivity concentrations were determined to establish the present contamination levels compared with other radionuclides {sup 137}Cs, {sup 237}Np, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Pu and {sup 241}Am. The results showed that {sup 242}Cm and {sup 244}Cm existed in the detectable levels in the Irish Sea sediment and the concentration of {sup 242m}Am was evaluated from that of {sup 242}Cm. The {sup 242m}Am/{sup 239,240}Pu and {sup 244}Cm/{sup 239,240}Pu inventory ratios in the sediment core were about 0.04% and 0.3%, respectively. The total amount of {sup 242m}Am discharged into the Irish Sea from the start of the operation of BNFL Sellafield in 1952 ...
1999-03-01
Anisotropy of fission of /sup 242//sup m/Am by fast neutrons
Energy Technology Data Exchange (ETDEWEB)
Careful measurements do not confirm an anomalous anisotropy in the angular distribution of fission fragments from the fast neutron fission of Americium 242. The energy range covered was 1.60-3.15 MeV. (AIP)
1985-10-01
International Nuclear Information System (INIS)
A method for express determination of "2"3"4"-"2"3"8U, "2"3"8"-"2"4"2Pu, "2"4"1"-"2"4"3Am and "2"4"2"-"2"4"4Cm content in fuel 'hot' particles and spent nuclear fuel is offered. The method is based on precision measurement of a sample #alpha# activity followed by estimate of relative contributions of individual nuclides, or groups of radionuclides, to total activity. Segregation in separate fractions of uranium, plutonium, americium and curium was made with the help of ion-exchange chromatography. Results are presented of "2"3"4"U, "2"3"8U, "2"3"8"Pu,"2"3"9"+"2"4"0Pu, "2"4"1Pu, "2"4"2Pu, "2"4"1"Am, "2"4"2"mAm, "2"4"3Am "2"4"2"Cm and "2"4"4Cm definition in 'hot' particles sampled in Chernobyl NPP surroundings, Opportunities to apply this method for identifying radionuclide content of spent nuclear fuel are discussed.
AMS Project Plan - Alpha Magnetic Spectrometer - NASA
Feb 19, 2009 ... Standard Practice for Military Marking. MIL-STD-130. K. 1/15/00. Identification Marking of U.S. Military Property. MIL-STD-2073-1. D. Notice 1 ...
A Gallium Arsenide MESFET Operational Amplifier for Use in ...
... 19. AmSTR.ACT (Continuq 9n =usff i En " Adentity by bo nwnb Agallumarsemoe t(a.") MEtFET ... 2%ITE 4T (Include Area Code) InghE SMO ...
1993-12-01
8:00am - Jack Marburger's Remarks to the Committee - NASA
Aug 5, 2009 ... and the intelligence community as well. The subsequent process was carried ..... The source of this criticism ranges from concern over technical capability to .... universe with both human and robotic missions, and open ...
{sup 242m}Am fueled nuclear battery
Energy Technology Data Exchange (ETDEWEB)
A nuclear battery based on the direct energy conversion of the fission products is presented. Such energy conversion is possible by using a nuclear reactor with ultra-thin fuel elements of 0.2 {mu}m of {sup 242m}Am. The amount of nuclear fuel is 376 g and the dimensions of the battery are 2.4x2.4x2.4 m{sup 3} (including the vacuum spacing), with a BeO moderator and Be electrodes. The total power of the reactor is 10.6 MW and the electrical power is 0.652 MW.
2004-10-01
The AMS-02 electromagnetic calorimeter
The Electromagnetic Calorimeter (ECAL) of the AMS-02 experiment is a lead-scintillating fibers sampling calorimeter characterized by high granularity that allows to image the longitudinal and lateral showers development, a key issue to provide high electron/hadron discrimination. The light collection system and the FE electronics are designed to let the calorimeter operate over a wide energy range from few GeV up to 1 TeV. A full-scale prototype of the e.m. calorimeter was tested at CERN in October 2001 using electrons and pions beams with energy ranging from 3 to 100 GeV. Effective sampling thickness, linearity and energy resolution were measured. (8 refs).
2002-01-01
Measurement of the energy dependence of the neutron fission cross section of /sup 242/Am/sup m/
Energy Technology Data Exchange (ETDEWEB)
Measurements were made of the cross section for /sup 242/Am/sup m/ fission induced by neutrons in the energy range 0.04< or =E/sub n/< or =4.52 MeV as well as by neutrons with E/sub n/roughly-equal14.8 MeV. An electrostatic generator and a low-voltage accelerating tube were used to generate the quasimonochromatic neutrons. Measurements in the low-energy region were made by using the time-of-flight technique in neutrons from a nuclear explosion. Results of the measurements are compared with previously published data.
1981-03-01
Level structure of the doubly-odd /sup 242/Am nucleus
Energy Technology Data Exchange (ETDEWEB)
The level structure of the doubly-odd /sup 242/Am nucleus was investigated by means of thermal-neutron-capture gamma-ray and conversion electron spectroscopy. Pair, curved-crystal, and ..beta.. spectrometers were used. The data from these measurements, combined with previous direct reaction results, permit us to establish a detailed level scheme including six new well-developed bands. Our experimental results are interpreted in the framework of the Nilsson model. Precise Gallagher-Moszkowski splittings and Newby odd-even shifts extracted from the data are compared with theoretical calculations.
1988-06-01
High efficiency GaInP/GaAs tandem solar cells
Energy Technology Data Exchange (ETDEWEB)
We report on multijunction GaInP/GaAs photovoltaic cells with total-area efficiencies of 29.5% at one-sun concentration and air mass (AM) 1.5 global and 25.7% one-sun, AM0. These values represent the highest efficiencies achieved by any solar cell under these illumination conditions. Three key areas in this technology are identified and discussed: the grid design, front surface passivation of the top cell, and bottom surface passivation of both cells. Aspects of cell design related to its operation under different solar spectra and under concentration are also discussed.
1994-06-30
Comparative AMS radiocarbon dating of pretreated versus non-pretreated tropical wood samples
Energy Technology Data Exchange (ETDEWEB)
Several wood samples collected from Dorslandboom, a large iconic African baobab (Adansonia digitata L.) from Namibia, were investigated by AMS radiocarbon dating subsequent to pretreatment and, alternatively, without pretreatment. The comparative statistical evaluation of results showed that there were no significant differences between fraction modern values and radiocarbon dates of the samples analyzed after pretreatment and without pretreatment, respectively. The radiocarbon date of the oldest sample was 993 +- 20 BP. Dating results also revealed that Dorslandboom is a multi-generation tree, with several stems showing different ages.
2010-04-15
Basic criticality relations for gas core design
Energy Technology Data Exchange (ETDEWEB)
Minimum critical fissile concentrations are calculated for U-233, U-235, Pu-239, and Am-242m mixed homogeneously with hydrogen at temperatures to 15,000K. Minimum critical masses of the same mixtures in a 1000 liter sphere are also calculated. It is shown that propellent efficiencies of a gas core fizzler engine using Am-242m as fuel would exceed those in a solid core engine as small as 1000L operating at 100 atmospheres pressure. The same would be true for Pu-239 and possibly U-233 at pressures of 1000 atm. or at larger volumes.
1992-05-22
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 2 sup 4 sup 2 sup m Am and sup 2 sup 4 sup 3 Am, and fission product nuclides of sup 9 sup 9 Tc and sup 1 sup 4 sup 0 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 2 sup 4 sup 2 sup m Am and sup 2 sup 4 sup 3 Am after further improvements. For sup 9 sup 9 Tc and sup 1 sup 4 sup 0 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 - sup 5 eV to 20 MeV in the ENDF-6 format, and adopted to JENDL-3.3.
2002-01-01
Recycling heterogeneous americium targets in a boiling water reactor
International Nuclear Information System (INIS)
One of the limiting contributors to the heat load constraint for a long term spent fuel repository is the decay of americium-241. A possible option to reduce the heat load produced by Am-241 is to eliminate it via transmutation in a light water reactor thermal neutron environment, in particular, by taking advantage of the large thermal fission cross section of Am-242 and Am-242m. In this study we employ lattice loading optimization techniques to define the loadings and arrangements of fuel pins with blended americium and uranium oxide in boiling water reactor bundles, specifically, by defining the incineration of pre-loaded americium as an objective function to maximize americium transmutation. Subsequently, the viability of these optimized lattices is tested by assembling them into bundles with Am-spiked fuel pins and by loading these bundles into realistic three-dimensional BWR core-wide simulations ...
2010-02-01
Optimization of americium-loaded lattices tested in 3D BWR core-wide simulations
International Nuclear Information System (INIS)
One of the limiting contributors to the heat load constraint for the Yucca Mountain repository is the decay of Americium 241. A possible option to reduce the heat load produced by Am-241 is to eliminate or transmute it in a light water reactor thermal neutron environment, particularly, by taking advantage of the thermal fission cross section of Am-242 and Am-242m. In this study we employ lattice loading optimization techniques to define the americium/uranium blending and pin arrangements via an adaptation of the code FORMOSA-L to include the incineration of preloaded americium as an objective function. The optimization routines were designed to maximize americium transmutation, while maintaining power peaking below a predefined constraint. The viability of these lattice designs has been analyzed by creating bundles with these Am-spiked lattices and by loading these bundles into realistic 3D BWR ...
2008-09-14
International Nuclear Information System (INIS)
The nuclide "2"4"1Am decays by alpha emission to "2"3"7Np. Most of the decays (84.6%) populate the excited level of "2"3"7Np with energy of 59.54 keV. Digital coincidence counting was applied to standardize a solution of "2"4"1Am by alpha-gamma coincidence counting with efficiency extrapolation. Electronic discrimination was implemented with a pressurized proportional counter and the results were compared with two other independent techniques: Liquid scintillation counting using the logical sum of double coincidences in a TDCR array and defined solid angle counting taking into account activity inhomogeneity in the active deposit. The results show consistency between the three methods within a limit of a 0.3%. An ampoule of this solution will be sent to the International Reference System (SIR) during 2009. Uncertainties were analysed and compared in detail for the three applied methods.
2009-09-07
International Nuclear Information System (INIS)
We provide a numerically efficient procedure to perform LDA+Hubbard I calculations including self-consistency over the charge density in the FP-LAPW basis. The method is applied to Pu, Am, and PuAm and PuCe alloys. Our results for valence photoemission spectra (PES) agree with experimental data and with previous LDA+DMFT calculations. Analysis of the J=5/2 and J=7/2 contributions to the f-occupation supports the intermediate-coupling picture of f-states in heavy actinides. The electronic specific heat coefficient is calculated for PuAm and PuCe alloys in reasonable agreement with recent experiments. We show that Pu atoms keep their mixed-valence character in these alloys. Next, we study electronic and spectral properties of Pu-based superconductor PuCoGa_5 and obtain good agreement with experimental PES. Finally, we analyze surface effects. In Pu monolayer, we find substantial modification of PES due to 5f-electron ...
2010-03-21
Role of accelerator mass spectrometry in biological dosimetry
International Nuclear Information System (INIS)
Understanding risks from exposures to carcinogens and other chemicals depends upon measurement of their dose to target tissues and their reactivity with critical macromolecules. The authors have used AMS detection of radio-isotopes to assess doses and reactivities at low, environmentally relevant doses. Several biomedical investigations show the effectiveness of quantification of biologically important events at extremely high sensitivity with AMS. Specifically, they have measured the addition of environmental carcinogens such as 2-amino-3,8-dimethylimidazo[4,5-f]-quinoaxaline (MelQx), a chemical found in cooked food, to DNA at concentrations relevant to human exposure. Other low level detection problems in biology, such as immunoassay assessment of small environmental chemicals, is being developed with attomole sensitivity. AMS also aids the assessment of genotoxic risks from chemicals by quantifying the binding of labeled ...
1992-04-05
A new method, near-infrared laser desorption/ionization aerosol mass spectrometry (NIR-LDI-AMS), is described for the real time analysis of organic aerosols at atmospherically relevant mass loadings. Use of a single NIR laser pulse to vaporize and ionize particle components deposited on an aluminum probe results in minimal fragmentation to produce exclusively intact pseudomolecular anions at [M-H](-). Limits of detection (total particulate mass sampled) for oxidized compounds of relevance to atmospheric primary and secondary organic aerosol range from 89 fg for pinic acid to 8.8 pg for cholesterol. NIR-LDI-AMS was used in conjunction with the University of Vermont Environmental Chamber to study secondary organic aerosol (SOA) formation from ozonolysis of limonene at total aerosol mass loadings ranging from 3.2 to 25.0 ?g m(-3) and with a time resolution of several minutes. NIR-LDI-AMS permitted direct delineation between ...
2010-10-01
Measurement of the /SUP 242m/ Am neutron fission cross section
Energy Technology Data Exchange (ETDEWEB)
The fission cross section of /SUP 242m/ Am has been measured from 0.005 eV to 20 MeV using time-of-flight techniques at the Oak Ridge Electron Linear Accelerator. A hemispherical plate fission ionization chamber with five pairs of plates contained three deposits totaling 507 ..mu..g of /SUP 242m/ Am, one deposit of 168 ..mu..g /sup 235/U, and a ''weightless'' deposit of /sup 252/Cf, which served as a monitor of chamber performance. The fission of /sup 235/U, served as the cross-section standard for energies above 101 keV while /sup 6/Li(n,..cap alpha..), normalized to /sup 235/U fission in the 7.8- to 11.0-eV interval, served as a shape standard below 101 keV. Approximately 360 h of data were obtained at a flight path distance of 9.1 m, primarily with 40-ns bursts. Particular attention was paid to correction of backgrounds, especially inscattered-neutron-induced events. The fission resonance integral was ...
1983-05-01
Measurement of the /SUP 242m/ Am neutron fission cross section
International Nuclear Information System (INIS)
The fission cross section of /SUP 242m/ Am has been measured from 0.005 eV to 20 MeV using time-of-flight techniques at the Oak Ridge Electron Linear Accelerator. A hemispherical plate fission ionization chamber with five pairs of plates contained three deposits totaling 507 #mu#g of /SUP 242m/ Am, one deposit of 168 #mu#g "2"3"5U, and a ''weightless'' deposit of "2"5"2Cf, which served as a monitor of chamber performance. The fission of "2"3"5U, served as the cross-section standard for energies above 101 keV while "6Li(n,#alpha#), normalized to "2"3"5U fission in the 7.8- to 11.0-eV interval, served as a shape standard below 101 keV. Approximately 360 h of data were obtained at a flight path distance of 9.1 m, primarily with 40-ns bursts. Particular attention was paid to correction of backgrounds, especially inscattered-neutron-induced events. The fission resonance integral was found to be 1800 + or - 65 b.
International Nuclear Information System (INIS)
The extraction of Am(III) and Eu(III) has been investigated using mixtures of synthesized aromatic dithiophosphinic acids (R_2PSSH) and tributylphosphate (TBP), trioctylphosphine oxide (TOPO) or tributylphosphine oxide (TBPO) in toluene from nitric acid (0.01-1.5 mol l"-"1). There was no detectable extraction when R_2PSSHs were used alone as extractants for either Am(III) or Eu(III) (D_A_m_,_E_u<10"-"4) under the experimental conditions used in this study. High separation factors (D_A_m/D_E_u>20) with D_A_m>1 were achieved in the nitric acid range 0.1-1 moll"-"1 by means of a synergistic mixture of bischlorodithiophosphinic acid with TBP, TOPO or TBPO. (orig.)
1998-06-12
British Library Electronic Table of Contents (United Kingdom)
The generalized demodulation time-frequency analysis is a novel signal processing method, which is particularly suitable for the processing of multi-component amplitude-modulated and frequency-modulated (AM-FM) signals as it can decompose a multi-component signal into a set of single-component signals whose instantaneous frequencies own physical meaning. While fault occurs in gear, the vibration signals measured from gearbox would exactly display AM-FM characteristics. Therefore, targeting the modulation feature of gear vibration signal in run-ups and run-downs, a fault diagnosis method in which generalized demodulation time-frequency analysis and envelope order spectrum technique are combined is put forward and applied to the transient analysis of gear vibration signal. Firstly the multi-...
2010-01-01
Solubility of AmOHCO{sub 3} in aqueous solution under atmospheric conditions
Energy Technology Data Exchange (ETDEWEB)
Modeling calculations on the solubility of americium have indicated that basic americium carbonate, and not americium trihydroxide, is the solubility-controlling solid in the pH range from 6 to 10 under the influence of atmospheric CO{sub 2}. The solubility of crystalline {sup 243}AmOHCO{sup 3} has been investigated in batch experiments in near-neutral and basic solutions as a function of dissolution time in 0.1 M NaClO{sup 4} at room temperature under oxic conditions. After the solutions reached steady-state conditions, the influence of dissolved solids on the americium concentration in the supernatant solution was studied by utilizing several experimental methods to separate the solution phase from the solid. The solids were characterized by X-ray powder diffraction analysis.
1987-12-01
Small propulsion reactor design based on particle bed reactor concept
In this paper Particle Bed Reactor (PBR) designs are discussed which use /sup 233/U and /sup 242m/Am as fissile materials. A constant total power of 100MW is assumed for all reactors in this study. Three broad aspects of these reactors is discussed. First, possible reactor designs are developed, second physics calculations are outlined and discussed and third mass estimates of the various candidates reactors are made. It is concluded that reactors with a specific mass of 1 kg/MW can be envisioned of /sup 233/U is used and approximately a quarter of this value can be achieved if /sup 242m/Am is used. If this power level is increased by increasing the power density lower specific mass values are achievable. The limit will be determined by uncertainties in the thermal-hydraulic analysis. 5 refs., 5 figs., 6 tabs.
1989-01-01
Role of additives in wood plastic composite of water soluble monomer
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 against attacks by insects and microbes. (author).
1994-01-01
Real-time neutron monitoring method using an imaging plate
Energy Technology Data Exchange (ETDEWEB)
A novel system for real-time radiation monitoring in reactor or accelerator facilities has been studied using an imaging plate. The authors made a feasibility study on a new neutron detection system using both photostimulated luminescence (PSL) and prompt luminescence (PL) generated in a neutron imaging plate (NIP) when the NIP is irradiated by neutrons. A readout system consisting of a semiconductor laser and a photomultiplier tube was fabricated for the purpose. It was confirmed that the system can measure both PSL and PL, where Am-Li was used as a neutron source. It may be possible to establish a new wide-range neutron monitoring system using the developed system as a PL mode normally, and as a PSL mode in case of intense neutron dose that cannot be measured in a PL mode because of saturation of the detection system. (author)
1999-07-01
Real-time neutron monitoring method using an imaging plate
International Nuclear Information System (INIS)
A novel system for real-time radiation monitoring in reactor or accelerator facilities has been studied using an imaging plate. The authors made a feasibility study on a new neutron detection system using both photostimulated luminescence (PSL) and prompt luminescence (PL) generated in a neutron imaging plate (NIP) when the NIP is irradiated by neutrons. A readout system consisting of a semiconductor laser and a photomultiplier tube was fabricated for the purpose. It was confirmed that the system can measure both PSL and PL, where Am-Li was used as a neutron source. It may be possible to establish a new wide-range neutron monitoring system using the developed system as a PL mode normally, and as a PSL mode in case of intense neutron dose that cannot be measured in a PL mode because of saturation of the detection system. (author)
1999-04-19
Prompt neutron multiplicities for the transplutonium nuclides
The direct determination of the average prompt neutron emission values is reviewed, and a method of comparing different sites of neutron emission multiplicity distribution values is described. Measured and recommended values are tabulated for these nuclides: /sup 241/Am, /sup 242/Am, /sup 242/Cm, /sup 243/Cm, /sup 244/Cm, /sup 246/Cm, /sup 247/Cm, /sup 248/Cm, /sup 250/Cm, /sup 245/Cm, /sup 249/Bk, /sup 246/Cf, /sup 249/Cf, /sup 250/Cf, /sup 252/Cf, /sup 254/Cf, /sup 251/Cf, /sup 253/Es, /sup 254/Es, /sup 244/Fm, /sup 246/Fm, /sup 255/Fm, /sup 252/No, /sup 254/Fm, /sup 256/Fm, /sup 257/Fm. 59 refs., 24 tabs. (LEW)
1985-01-01
Microstructure and mechanical behaviour of an elevated temperature Mg-rare earth based alloy
International Nuclear Information System (INIS)
AM-SC1 is a heat treatable magnesium alloy that has been specifically developed to achieve the elevated temperature strength and creep properties necessary for engine block applications. This paper describes the interrelationship between the microstructure and the mechanical properties of AM-SC1. The compressive and tensile strengths are relatively insensitive to temperature up to and including 450 K and the tensile yield behaviour deviates from a standard Hall-Petch relationship at grain sizes below 200 ?m. The microstructural features contributing to the creep resistance are both inter- and intra-granular in nature and are on length scales from nanometers to micrometers. The creep behaviour at 423 K and 450 K is diffusion controlled, with any contribution from the grain boundaries being negligible.
2009-04-15
Energy Technology Data Exchange (ETDEWEB)
Mass and charge distributions of products from fission of sup(242m)Am induced by thermal neutrons have been investigated by means of the semiconductor spectrometry of ..gamma.. radiation from a mixture of non-separated fragment nuclei. Specimens of the fissible material have been irradiated in the vertical experimental channel of the research reactor then the measurements have been performed with calibrated semiconductor detectors. Three experiments with substantially different irradiation times have been performed to expand the nomenclature of the investigated fission products. The spectra of ..gamma.. radiation from the mixture of fission products, and time dependences of the counting rates at the total absorption peaks have been handled with computers. The obtained yields are compared with data of previous investigations performed with different experimental methods, as well as with the calculated one.
1985-03-01
Energy Technology Data Exchange (ETDEWEB)
The mass and charge distributions in an unseparated mix of fission product nuclei from thermal-neutron fission of /sup 242m/Am were studied through semiconductor gamma-ray spectrometry. Samples of the fissionable material under study were irradiated in a vertical irradiation tube of the MIFI IRT research reactor. Following irradiation, measurements were made on aperture-calibrated semiconductor detectors. For broader identification of fission fragment nuclides three experiments were conducted that differed substantially in irradiation duration. The spectrum of gamma radiation from the mix of fission products and the time dependences of count rate at total absorption peaks were analyzed on SM-4 and Iskra-226 computers. The values of yields obtained were compared with data of investigations conducted earlier with other experimental methods, and also with the results of calculations.
1985-03-01
MOCVD growth of GaAs solar cells on silicon substrates
Energy Technology Data Exchange (ETDEWEB)
This paper reports advances in the development of solar cells made from GaAs-on-Si structures prepared by metalorganic chemical vapor deposition (MOCVD). The use of concentrator cells, operating at [similar to]200 suns, has led to the efficiency achievements of 21.3% (AM1.5D) for a GaAs-on-Si solar cell, and 27.6 (AM1.5D) for a homoepitaxial GaAs cell. The development of epitaxial multilayer dielectric mirrors (Bragg reflectors), as back-surface reflectors in thin-film GaAs cells, on both Si and GaAs substrates, is shown to lead to modest efficiency increases, over that of conventional designs.
1992-12-01
International Nuclear Information System (INIS)
The Moessbauer emission spectrum of "2"4"1Am metal was investigated for influences of radiation self damage. Samples were kept continuously for 230 h at 4.2 K and spectra were taken each 10 to 20 h. No change in f-factor was observed, while the linewidth increased monotonically and reached saturation after approximately 180 h. The original width could be reproduced by a brief warming to room temperature. The increase in width reflects the change in quadrupole interaction due to the creation of lattice defects. The constancy of the f-factor indicates that the basic crystalline structure is retained.
International Nuclear Information System (INIS)
The helium releases were investigated in FBR fuel pins irradiated to high burn-up. The released amounts increased with the increase of burn-up, but no burn-up dependence of their release fraction to total amounts generated was seen. The contents of "2"4"1Am in fuel pellets affected the released amounts. The effect of released helium on the internal pressure in fuel pins was smaller in FBR fuel pins than in LWR fuel pins, but released helium in fuel pins containing increased amounts of "2"4"1Am, which are anticipated in future FBRs, is expected to affect the internal pressure.
2010-06-01
Energy Technology Data Exchange (ETDEWEB)
The intrinsic energy levels in the doubly odd isotopes of Np with mass number 238 and of Am with mass numbers 240, 242 and 244 are calculated using the zero-range neutron-proton residual interaction whose parameters are evaluated using the atomic masses and the ground state Gallagher-Moszkowski splitting energy in each case. A configuration dependence of the residual interaction is in evidence in several cases. The results are compared with the experimental data and the comparison is used to check on the two-particle configuration assignments to the intrinsic states in the respective spectra. Encouraged by the nature and the degree of the agreement of the theory with the available experimental data, predictions are made about the expected location of the as yet unobserved two-quasiparticle states in these nuclei.
1982-01-18
British Library Electronic Table of Contents (United Kingdom)
Photoelectron resonance capture ionization aerosol mass spectrometry (PERCI-AMS) has been applied to the analysis of proxies for marine aerosols with and without ozone; proxies used were mixed oleic acid-amino acid particles. The mechanism of ion formation for serine (104 m/z), glutamic acid (146 m/z), and phenylalanine (164 m/z) was dissociative electron attachment. This corresponds to loss of the hydrogen atom only, allowing for straightforward identification of the free amino acids. No ozonolysis products for the free amino acids were observed, even at high concentrations of ozone (500 ppm for 19 s). The direct detection of a novel gas-phase hydrated anion, [serine + H2O-H]-, is described. These preliminary results suggest that PERCI-AMS may provide an effective, simple and direct onlin...
2008-01-01
Delayed neutron yields: Time dependent measurements and a predictive model
Energy Technology Data Exchange (ETDEWEB)
The delayed neutrons from neutron-induced fission in /sup 232/U, /sup 237/Np, /sup 238/Pu, /sup 241/Am, /sup 242/Am/sup m/, /sup 245/Cm, and /sup 249/Cf were studied for the first time; those from /sup 232/Th, /sup 233/U, /sup 235/U, /sup 238/U, /sup 239/Pu, /sup 241/Pu, and /sup 242/Pu were measured again. The data were used to develop an expression for the prediction of the absolute delayed neutron yield, and the prediction of delayed neutron emission with time. This approach accurately predicts observed delayed neutron yields and decay characteristics. A fission product yield model was used in conjunction with delayed neutron emission probability to analytically predict delayed neutron characteristics. The results of this analysis are in excellent agreement with experimental values.
1981-03-01
Burning nuclear wastes in fusion reactors
Energy Technology Data Exchange (ETDEWEB)
We have studied actinide burn-up in ICF reactor pellets; i.e., 14 MeV neutron fission of the very long-lived actinides that pose storage problems. A major advantage of pellet fuel region burn-up is safety: only milligrams of highly toxic and active material need to be present in the fusion chamber, whereas blanket burn-up requires the continued presence of tons of actinides in a small volume. The actinide data tables required for Monte Carlo calculations of the burn-up of /sup 241/Am and /sup 243/Am are discussed in connection with a study of the sensitivity to cross section uncertainties. More accurate and complete cross sections are required for realistic quantitative calculations.
1980-02-20
Anwendung von Trapezblechstegen im Bruckenbau
British Library Electronic Table of Contents (United Kingdom)
Trapezblechstege im Bruckenbau kommen trotz der groen Vorteile, die diese Bauweise bietet, in Deutschland bisher nur an einem Pilotprojekt zur Anwendung. Durch die charakteristischen Eigenschaften des Trapezbleches entstehen konstruktive und wirtschaftliche Vorteile gegenuber herkommlichen Bruckenbauweisen. Allerdings lassen die aktuell gultigen Regelwerke aufgrund fehlender Kenntnis zum Tragverhalten und mangelnder Erfahrung keine wirtschaftliche Ausbildung zu. Dies zeigt sich am Beispiel des Pilotprojekts. Die Ausbildung der Verbundfuge wurde hier nur sehr unbefriedigend gelost und verdeutlicht somit die Notwendigkeit einfacher und praktikabler Verbindungsmoglichkeiten. Am Institut fur Leichtbau Entwerfen und Konstruieren der Universitat Stuttgart wurde in Zusammenarbeit mit dem Institut...
2009-01-01
British Library Electronic Table of Contents (United Kingdom)
Abstract:- Significant interest has emerged in the introduction of food packaging materials manufactured from biodegradable polymers that have the potential to reduce the environmental impacts associated with conventional packaging materials. Current technologies in active packaging enable effective antimicrobial (AM) packaging films to be prepared from biodegradable materials that have been modified and/or blended with different compatible materials and/or plasticisers. A wide range of AM films prepared from modified biodegradable materials have the potential to be used for packaging of various food products. This review examines biodegradable polymers derived from polysaccharides and protein-based materials for their potential use in packaging systems designed for the protection of food ...
2011-01-01
An americium-fueled gas core nuclear rocket
Energy Technology Data Exchange (ETDEWEB)
A gas core fission reactor that utilizes americium in place of uranium is examined for potential utilization as a nuclear rocket for space propulsion. The isomer [sup 242m]Am with a half life of 141 years is obtained from an (n, [gamma]) capture reaction with [sup 241]Am, and has the highest known thermal fission cross section. We consider a 7500 MW reactor, whose propulsion characteristics with [sup 235]U have already been established, and re-examine it using americium. We find that the same performance can be achieved at a comparable fuel density, and a radial size reduction (of both core and moderator/reflector) of about 70%.
1993-01-10
Energy Technology Data Exchange (ETDEWEB)
This report presents the results of a study dealing with the homogeneous recycling of either Pu or Pu+Np or Pu+Np+Am or Pu+Np+Am+Cm in PWRs using MOX-UE fuel, i.e. standard MOX fuel with a U235 enriched uranium support instead of the standard tail uranium (0.25%) for standard MOX fuel. This approach allows to multirecycle Pu or TRU (Pu+MA) as long as U235 is available, by keeping the Pu or TRU content in the fuel constant and at a value ensuring a negative moderator void coefficient (i.e. the loss of the coolant brings imperatively the reactor to a subcritical state). Once this value is determined, the U235 enrichment of the MOX-UE fuel is adjusted in order to reach the target burnup (51 GWd/t in this study).
2009-05-01
Using neutron-activation detectors with fissionable nuclides
Energy Technology Data Exchange (ETDEWEB)
Presented are results of a test of a method for measuring neutron fluences using detectors with fissionable nuclides. The investigations show the soundness of of using neutron-activation detectors of the type Am for mesurements in nuclear installations for values of thermal-neutron fluence of from 10/sup 13/ to 10/sup 20/ neutrons/cm/sup 2/ with exposure for up to several months. The proposed method can be used for prolonged measurements in strong fields of both thermal and fast neutrons.
1986-09-01
Theory of isomer ratios of shape isomers in heavy ion induced reactions
A method for the calculation of excitation functions and isomer ratios, for shape isomers, in heavy ion induced reactions is proposed. The calculated values of excitation functions and isomer ratios agree very well with the experimental values for the reaction /sup 238/U(/sup 11/B, alpha 3n)/sup 242/Am. (auth)
1973-11-12
Separation of Pu-238 and Pu-242 from irradiated Am-241
International Nuclear Information System (INIS)
... americium 241 americium 242 daughter products ion exchange chromatography isotope ratio neutron beams plutonium 238 plutonium 242 ... Authors Watanabe, Kenju; Sagawa, Chiaki; Ueno, Kaoru (Japan Atomic Energy Research Inst., Tokai, Ibaraki. Tokai Research Establishment)
Optical and statistical model calculation of the americium 242m capture cross section
International Nuclear Information System (INIS)
The capture cross sections of Am 242m can be deduced from resonances analysis at low energy and computed with theoretical models at high energy. In this work, a coherent set of cross sections which reproduced the experimental values of the fission cross sections is computed. These calculations were performed for an energy of the incoming neutron between 1 keV and 1 MeV.
International Nuclear Information System (INIS)
Airborne lead particulates collected on a membrane filter were determined by the nondestructive X-ray fluorescence method. The gamma/X radionuclide source "2"4"1Am/Ag and a scintillation detector with a NaI/Tl crystal were used for the excitation and detection, respectively, of L X-rays of Pb. One can say, with reference to the obtained results, that the sensitivity and accuracy of the measurement is more than adequate for monitoring the Pb level in air. (author).
1980-01-01
Neutron multiplicities for the transplutonium nuclides
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).
1985-01-01
Neutron multiplicities for the transplutonium nuclides
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
1985-01-01
... I worked on the Young City Farmers course in 2008, where I was voted the best-spoken bus driver and teacher the participants had ever had!! I am a representative of the University for widening participation and outreach, for my enthusiasm, communication and personal skills. I look forward to meeting you, welcoming you to the College and helping with your learning and progression. Sam Parkes Hi I'm ...
Energy Technology Data Exchange (ETDEWEB)
Biological cells of the nitrogen fixating bacteria Xanthobacter autotrophicus GZ 29 have been cultivated with 57-Fe, and from the nitrogenase of these cells the 57-Fe marked molybdenum-iron-protein is extracted. The Moessbauer spectra of this enzyme show that the structure of the iron cluster is similar to the structure in the molybdenum-iron-proteins of Azotobacter vinelandii, Klebsiella pneumoniae or Clostridium pasteurianum.
1983-05-01
UK PubMed Central (United Kingdom)
We have shown previously that raising extracellular Ca2+ inhibited the apical 70-pS K channel in the thick ascending limb (TAL; Wang, W.H., M. Lu, and S.C. Hebert. 1996. Am....Full Text Available
2002-01-01
Energy Technology Data Exchange (ETDEWEB)
Fe, Mn, Ni, V, Ti and Mo were determined in aerosols from manual arc welding. Samples of welding aerosols were trapped on a Synpor 4 filter. The amount of determined elements in aerosols was detected using the method of radionuclide X-ray fluorescence analysis. A /sup 241/Am annular source was used as the source of excitation radiation and radiation was processed using a Si(Li) spectrometer.
1984-10-01
International Nuclear Information System (INIS)
Fe, Mn, Ni, V, Ti and Mo were determined in aerosols from manual arc welding. Samples of welding aerosols were trapped on a Synpor 4 filter. The amount of determined elements in aerosols was detected using the method of radionuclide X-ray fluorescence analysis. A "2"4"1Am annular source was used as the source of excitation radiation and radiation was processed using a Si(Li) spectrometer. (E.S.).
1984-01-01
Heavy metals and some other elements in medicinal plants. Determined by X-ray fluorescence analysis
International Nuclear Information System (INIS)
Determination of Mn, Fe, Cu, Zn, Hg, Pb, Br, Se, Rb, Sr and Cd in the medicinal plants by radionuclide X-ray fluorescence analysis (using "2"3"8Pu, "2"4"1Am/Ag and "1"2"5I) is described. (author). 12 refs., 2 tabs.
1995-01-01
HEDL evaluation of actinide cross sections for ENDF/B-V
International Nuclear Information System (INIS)
Sixteen actinide nuclei: U-234 and -236; Np-237; Pu-236, -237, -238, -242, and -244; Am-241, -242* and -243; and Cm-241, -242, -243, -244, and -248, have been evaluated for ENDF/B-V with particular attention given to the fast fission and capture cross sections. Seven nuclei have not appeared on ENDF/B before and major changes for previous ENDF/B files have been made.
Formation of iron oxides during mechanical activation in water
International Nuclear Information System (INIS)
It has been shown that mechanical milling of iron in water results in formation of nanocrystalline magnetite Fe3O4 with an average particle size of 0.6 ?m, saturation magnetization of 77 Am2/kg and coercivity of ?150 A/cm. Along with magnetite, an antiferromagnetic Fe-O phase (?10 wt%), which is an aggregate of small iron-oxygen clusters forms.
2007-05-21
Energy Technology Data Exchange (ETDEWEB)
About two dezen exhibitors from Switzerland and abroad presented their electric vehicles at the Geneva International Car Exhibition on March 5-15. Interesting new serial vehicles, attractive new prototypes, handsome oldtimer cars varied information and a competition to beat the long-distance world championship provided attractions for the visitors. (orig.).
1992-02-21
Determination of americium and plutonium in autopsy tissue: methods and problems
International Nuclear Information System (INIS)
The current methods used by the tissue analysis program at LASL for the determination of americium and plutonium in autopsy tissue are described. Problems affecting radiochemical yield are discussed. Included are problems associated with sample preparation, separation of plutonium from large amounts of bone ash, and reagent contamination. The average "2"4"2Pu tracer yield for 1800 Pu determinations is 78 +- 12%. The average "2"4"2Am tracer yield is 85 +- 7% for 40 determinations.
Determination of americium and plutonium in autopsy tissue: methods and problems
The current methods used by the tissue analysis program at LASL for the determination of americium and plutonium in autopsy tissue are described. Problems affecting radiochemical yield are discussed. Included are problems associated with sample preparation, separation of plutonium from large amounts of bone ash, and reagent contamination. The average /sup 242/Pu tracer yield for 1800 Pu determinations is 78 +- 12%. The average /sup 242/Am tracer yield is 85 +- 7% for 40 determinations.
1979-01-01
Curium isotopes and americium-242 m in Irish Sea sediment
International Nuclear Information System (INIS)
An intertidal estuarine sediment core was collected from Esk Estuary in the Irish Sea which had been contaminated by low-level radioactive liquid effluent from the nuclear fuel reprocessing plants at Sellafield, UK. The "2"4"2Cm and "2"4"3","2"4"4Cm radioactivity concentrations were determined to establish the present contamination levels compared with other radionuclides "1"3"7Cs, "2"3"7Np, "2"3"8Pu, "2"3"9","2"4"0Pu, "2"4"1Pu and "2"4"1Am. The results showed that "2"4"2Cm and "2"4"4Cm existed in the detectable levels in the Irish Sea sediment and the concentration of "2"4"2"mAm was evaluated from that of "2"4"2Cm. The "2"4"2"mAm/"2"3"9","2"4"0Pu and "2"4"4Cm/"2"3"9","2"4"0Pu inventory ratios in the sediment core were about 0.04% and 0.3%, respectively. The total amount of "2"4"2"mAm discharged into the Irish Sea from the start of the operation of BNFL Sellafield in 1952 to 1988 was estimated to be ...
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 ...
1975-11-17
Analysis of titanium and zirconium in red mud with energy dispersive x-ray spectrometry
Energy Technology Data Exchange (ETDEWEB)
An energy dispersive x-ray fluorescence technique was used for the determination of Titanium (Ti) and Zirconium (Zr) in red mud by using a standard addition method. An annular {sup 241}Am source is employed for excitation of K shells of elements. 13 refs., 2 figs., 1 tab.
1996-11-01
UK PubMed Central (United Kingdom)
The current investigation attempted to confirm the beneficial actions of a chemically characterized Radix Astragali decoction (AM-W) against type 2 diabetic (T2D) Sprague-Dawley (SD) rats. Using a case/control...Full Text Available
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
Main topic of the project was the manufacturing of highly efficient GaAs-solar cells and the fabrication of concentrator cells. During this process significant progress was made with the material preparation, the solar cell technology and the material and process characterisation. This succeeded in the following efficiencies: - GaAs solar cell made by MOVPE technology: 22.9% on 4 cm{sup 2} (AM1.5g) - GaAs solar cell made by LPE-ER process: 22.8% on 4 cm{sup 2} (AM1.5g) - GaAs concentrator solar cell made by LPE-ER process: 24.9% at C=100xAM1.5d - GaAs concentrator module with fresnel lenses: Module efficiency 20.1% (under irradiation of 793 W/m{sup 2}). Another main focus was the epitaxy of GaAs on Si substrate. Two different approaches were investigated. Together with the cooperation partner ASE, Heilbronn a selective growth technology was developed that led to a decreased crack formation. By a simultanous optimization of ...
1996-10-01
Energy Technology Data Exchange (ETDEWEB)
This work concerns the development of nuclear energy and nuclear waste management in particular. Two parts of this study can be distinguished. In the first part (theoretical), a thorium-plutonium fuel based on MOX and dedicated for PWR was investigated in order to transmute plutonium in a potentially low waste fuel cycle. It was shown that this type of fuel is not regenerative but could be used for a transition to the industrial thorium fuel cycle without building new reactors. Thanks to moderated neutron spectra and high loaded actinide mass in the core, U-233 is quickly created ({approx}300 kg/y) for a loss of about {approx}1200 kg of fissile plutonium. In the second part (experimental), we have developed and built a new reaction chamber to measure neutron cross sections of actinides by alpha-gamma spectroscopy. This experimental device (in principle transportable) was commissioned in the high flux reactor of ILL Grenoble. Neutron flux was measured by gamma spectroscopy of irradiated ...
2002-09-01
Energy Technology Data Exchange (ETDEWEB)
In the framework of nuclear waste transmutation studies, the Mini-INCA project has been initiated at CEA/DSM with objectives to determine optimal conditions for transmutation and incineration of minor actinides (MA) in high intensity neutron fluxes. Our experimental tools based on alpha- and gamma-spectroscopy of the samples and the development of micro fission chambers could gather either microscopic information on nuclear reactions (total or partial cross sections for neutron capture and/or fission reactions) or macroscopic information on transmutation and incineration potentials. Neutron capture cross sections of selected actinides ({sup 241}Am, {sup 242}Am, {sup 242}Pu, {sup 237}Np) have already been measured at ILL, showing some discrepancies when compared to evaluated data libraries but in overall good agreement with recent data. The studies and possibilities offer by the MEGAPIE project to assess neutronic performances of a 1 MW ...
2003-07-01
International Nuclear Information System (INIS)
In the framework of nuclear waste transmutation studies, the Mini-INCA project has been initiated at CEA/DSM with objectives to determine optimal conditions for transmutation and incineration of minor actinides (MA) in high intensity neutron fluxes. Our experimental tools based on alpha- and gamma-spectroscopy of the samples and the development of micro fission chambers could gather either microscopic information on nuclear reactions (total or partial cross sections for neutron capture and/or fission reactions) or macroscopic information on transmutation and incineration potentials. Neutron capture cross sections of selected actinides ("2"4"1Am, "2"4"2Am, "2"4"2Pu, "2"3"7Np) have already been measured at ILL, showing some discrepancies when compared to evaluated data libraries but in overall good agreement with recent data. The studies and possibilities offer by the MEGAPIE project to assess neutronic performances of a 1 MW spallation target ...
2003-09-01
Energy Technology Data Exchange (ETDEWEB)
The PuO/sub 2/ cask or SP 5320-2 and 3 cask is designed for surface shipment of americium or plutonium. The cask design was physically tested to demonstrate that it met the criteria specified in US ERDA Manual Chapter 0529, and Chapter I, Interstate Commerce Commission. The package has been assessed for transport of up to 357 grams of plutonium (403 grams PuO/sub 2/ powder) and up to 176 grams of americium (200 grams AmO/sub 2/ powder), having a maximum decay heat of 203 watts. Criticality evaluation alone would allow the shipment as Fissile Class II but the radiation level of the cask, measured at the time of shipment, may exceed 50 mrem/h at the surface and require shipment as Fissile Class III. Sample calculations address only the more restrictive of the two materials, which in most cases is /sup 238/PuO/sub 2/.
1980-05-01
Energy Technology Data Exchange (ETDEWEB)
On February 20th 1998 Auckland, the biggest city of New Zealand, was nearly paralyzed by an extended power failure. On this day the last of four cables supplying the central business district failed and caused a five weeks lasting blackout. This failure has caused costs of 128.3 Mio NZ Dollar for the affected utility Mercury Energy Ltd. The official ministerial inquiry was published on July 21st 1998 and reproaches the utility in an unusual clear manner. (orig.) [Deutsch] Am 20. Februar 1998 wurde Auckland, die groesste Stadt Neuseelands, von einer folgenschweren Unterbrechung der Stromversorgung nahezu lahmgelegt. An diesem Tag fiel das letzte von vier 110-kV-Kabeln zur Versorgung des Innenstadtbereiches aus und verursachte damit einen 5 Wochen dauernden Stromausfall. Diese Versorgungsunterbrechung hat bisher Kosten in Hoehe von 128,3 Mio NZ Dollar (rd. 115,5 Mio DM) fuer den oertlichen Stromversorger Mercury Energy Limited verursacht. Der am ...
1998-11-30
Production of rare earth enriched isotopes and americium 242 using metallphthalocyanines
International Nuclear Information System (INIS)
A technique of producing radioactive isotopes of rare earth elements (r.e.e.) and carrier free "2"4"2Am is suggested. The technique makes use of ''sandwich'' phthalocya=- nine complexes of r.e.e. and americium placed on sorbent. This is a new type of r.e.e. compounds and actinides (C_3_2H_1_6N_8)_2M (M is a metal ion) which are thermally, radiationally and chemically stable, dissolve well in some organic solvents and do not dissolve in water. Radiation and chemically stable activated carbon is used as a sorbent carrier. After irradiation the target is treated by a weakly acid solution or complex-former solution. Radioactive atoms formed due to (n, #gamma#)-reaction and desoleting the complex because of recoil transfer into the solution. When irradiating in the flux of 10"1"3 neutr./cm"2 x s for 1 hour it is possible to produce radioactive isotopes with the yield from 20 to 90%, for example "1"6"0Tb, "1"6"6Ho with enrichment factor > 100 and ...
Energy Technology Data Exchange (ETDEWEB)
Burnup calculations with SARC system were carried out to analyse the effects of plutonium build-up on criticality of MTR type research reactor PARR-1 using several WIMSD libraries based on evaluated nuclear data files ENDFB-VI.8, JEF-2.2, JEFF-3.1 and JENDL-3.2. For equilibrium core of the reactor, it was found that a net reactivity of more than 3.5 mk is induced due to build-up of plutonium isotopes during depletion. The plutonium credit amounts to 3% of the length of equilibrium cycle. From the analysis of actinide production in the core during burnup, it was observed that in most of the cases, the amounts of actinides obtained using various cross section libraries agree fairly with each other, however, significant differences were observed for {sup 238}Pu, {sup 241}Pu, {sup 242m}Am, {sup 243}Am, {sup 242}Cm and {sup 244}Cm for some libraries. The actinide chain analysis was conducted to investigate the reasons for the observed differences.
2006-12-15
Nanocrystallization of soft magnetic Fe-Co-Zr-Cu-B alloys
International Nuclear Information System (INIS)
In the present study, Fe_4_1Co_4_1 B_1_0Zr_7Cu_1 alloy has been investigated in order to evaluate its thermal stability and structure after heat treatment, as well as the impact of heat treatment on magnetic properties. X-ray diffractometry, differential scanning calorimetry, chemical composition microanalysis, transmission electron microscopy, and magnetic hysteresis loop measurement techniques were employed. The crystallization temperature of the as-quenched alloy is 490"oC (continuous heating at 5 "oC/min). The melt spun ribbon having 27 #mu#m in thickness was annealed for 1 hour at temperatures from 400 to 700 "oC. The alloy after treatment at about 550"oC underwent primary crystallization, with the average size of crystals under 20 nm. This specimen shows the coercive field of 38 A/m, as compared to about 160 A/m reported for a similar alloy (Fe_4_4Co_4_4B_4Zr_7Cu_1) with a similar structure, annealed at 600"oC. (author)
2001-09-23
Energy Technology Data Exchange (ETDEWEB)
Yields of light fission products (A = 68, 70-84, 87, 88, 94, 96, 98, 102 and 106-108), their kinetic energies and nuclear charge distributions (A 71-84, 87 and 88) in the thermal neutron induced fission of the odd-Z nucleus {sup 242m}Am(Z = 95) were measured using the mass-separator Lohengrin at the Institute Laue-Langevin in Grenoble (France). The mass yield curve shows a fine structure at A = 70, probably due to shell and/or odd-even effects affecting also the nuclear charge distribution. The analysis of isotopic chain yields gives evidence for a very low excitation energy of the lightest fission fragments observed. A preferential formation of fragments with even Z is found for this odd-Z compound nucleus. Calculated values for the local odd-even effect are comparable with those for the neighbouring even-Z fissile nuclides and increase from 13% to 30% with increasing asymmetry of the mass split (A{sub L} = 84 to 68 and Z{sub L} = 35 to 28). The neutron odd-even ...
1999-10-25
Isotope shift measurements at the {sup 242{ital f}}Am fission isomer
Energy Technology Data Exchange (ETDEWEB)
Isotope shift measurements have been performed for the {sup 242{ital f}}Am fission isomer with target production rates of only a few per second. The method is based on resonance ionization spectroscopy (RIS) in a buffer gas cell with radioactive decay detection of the ionization process (RADRIS). A relative isotope shift ratio X{sub {ital exp}}=IS{sup 242{ital f},241}/IS{sup 243,241}=41.7{plus_minus}0.9 has been measured for the 500.02 nm transition corresponding to a nuclear parameter A{sup 242{ital f},241}=(5.4{plus_minus}0.3) fm{sup 2}. A preliminary analysis of the quadrupole moment based on the deformed Fermi model of the nuclear charge distribution results in Q{sub 20}=35.9{plus_minus}1.1({sup +0.3}{sub {minus}0.7}) {sub model} eb. {copyright} 1995 {ital American} {ital Institute} {ital of} {ital Physics}
1995-04-01
Hans-Christian Jacobaeus (1879?1937)
British Library Electronic Table of Contents (United Kingdom)
Zusammenfassung Im Jahre 1910 f?hrte der schwedische Internist Hans-Christian Jacobaeus den ersten laparoskopischen Eingriff am Menschen in Stockholm durch. Grundlage seiner Pioniertat waren die tierexperimentellen Studien von Georg Kelling (1866?1945) aus Dresden, der im Jahre 1901 die erste Laparoskopie mittels eines Nitze-Zystoskops am Hund durchf?hrte. Jacobaeus ver?ffentlichte 1910 in der M?nchener Medizinischen Wochenschrift seine Erfahrungen mit den ersten 17 Laparoskopien unter dem Titel: ??ber die M?glichkeit die Zystoskopie bei Untersuchungen ser?ser H?hlen anzuwenden?. Hierbei nutzte er die neue Technik insbesondere zu diagnostischen Zwecken bei unklaren abdominellen Beschwerden und Funktionsst?rungen. Er war auch der Erste, der explizit auf die Gefahr der Darmverletzung bei Er?...
2006-01-01
Energy report Frankfurt am Main 1992; Stadt Frankfurt am Main. Energiebericht 1992
Energy Technology Data Exchange (ETDEWEB)
By joining the `climate association of European cities`, Frankfurt has agreed to reduce its CO{sub 2}-emissions by 50% by the year 2010. The so-called `climate offense 1991` was the first regulatory paper to be set up by a community to reach this goal over a long term. This report now represents the present level of the project. Main points are the development of houses with low entropy, the retrofitting of heating systems, water saving measures and energy management. (BWI) [Deutsch] Durch den Beitritt zum `Klima-Buendnis der Europaeischen Staedte` hat sich die Stadt Frankfurt/M. verpflichtet, die CO{sub 2}-Emissionen bis zum Jahr 2010 um 50% zu senken. Mit der sog. `Klimaoffensive 1991` wurde dann erstmals von einer Kommune in Deutschland ein detailliertes Regelwerk aufgestellt, um dieses Ziel langfristig erreichen zu koennen. Der vorliegende Bericht stellt den aktuellen Stand des Projektes dar. Kernpunkte sind die Entwicklung von Niedrigentropiehaeusern, die Umstellung von ...
1993-12-31
Dependence of fast reactor fuel burnup characteristics on nuclear data libraries
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 us to find out quantitatively the causative ...
2005-04-01
Energy Technology Data Exchange (ETDEWEB)
Plutonium-containing compounds vary widely in isotopic content, and as a result, the dose as function of isotopic content also varies considerably. Determination of the dose from neutrons, decay and capture gammas from plutonium in the form of compounds thus requires that the spontaneous fission and ({alpha},n) source and spectra from each individual isotope be known. To facilitate dose calculations from plutonium-containing compounds, we have calculated the spontaneous fission and ({alpha},n) sources and spectra for 1 g of each of the plutonium isotopes in the form of either PuF{sub 4} or PuO{sub 2}. As {sup 241}Am is often a component in a mixture of plutonium isotopic compounds, the source and spectra from 1 g of {sup 241}Am mixed with PuF{sub 4} or PuO{sub 2} has also been determined. Using these results, the neutron source and spectra may be determined for any sample composition. 2 refs., 3 tabs.
1996-10-01
Energy Technology Data Exchange (ETDEWEB)
Ventilation systems must ensure high room air quality with minimum energy consumption in all states of operation. Systems for ventilation on demand are increasing their market share. (orig./MSK) [Deutsch] Oberste Aufgabe von Raumlufttechnischen Anlagen ist die Sicherstellung guter Raumluftqualitaet bei minimalem Energieverbrauch unter allen Betriebsbedingungen. Um dieses Ziel zu erreichen, setzt sich am Markt zunehmend die bedarfsgeregelte Lueftung durch. (orig./MSK)
1997-11-01
Use of high energy radiation component as a reference source for radiometric testing
International Nuclear Information System (INIS)
The possibility of providing high accuracy of absorption and albedo methods of radiometric testing due to the use of high-energy radiation component that has passed through a barrier and gone from it in the opposite direction as a reference source, is considered. It is shown that the use of high-energy component of penetrating radiation as a reference source decreases the device response to the main interference in a much larger degree than its response to the change of measured parameter. Experiments are performed using steel pipes and plates. "2"4"1Am, "1"3"7Cs and "6"0Co are used as sources.
Total and spontaneous fission half-lives for uranium, plutonium, americium and curium nuclides
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).
1989-01-01
Light construction vehicles: ample choice; Leichte Baufahrzeuge: Reiche Auswahl
Energy Technology Data Exchange (ETDEWEB)
There are many types of allround trucks. But which is the adequate one for the manifold tasks in construction, horticulture and landscaping works? Passenger transport, load haulage and traction: the article takes a critical glance at what is on offer. (orig.) [German] Allroundlaster gibt es viele. Aber welcher ist der richtige fuer die vielfaeltigen Aufgaben am Bau und im Garten- und Landschaftsbau? Personen befoerdern, Lasten tragen und Anhaenger ziehen: Ein kritischer Blick aufs Angebot. (orig.)
1999-07-01
Knowledge base development for SAM training tools
Energy Technology Data Exchange (ETDEWEB)
Severe accident management can be defined as the use of existing and alternative resources, systems, and actions to prevent or mitigate a core-melt accident in nuclear power plants. TRAIN (Training pRogram for AMP In NPP), developed for training control room staff and the technical group, is introduced in this report. The TRAIN composes of phenomenological knowledge base (KB), accident sequence KB and accident management procedures with AM strategy control diagrams and information needs. This TRAIN might contribute to training them by obtaining phenomenological knowledge of severe accidents, understanding plant vulnerabilities, and solving problems under high stress. 24 refs., 76 figs., 102 tabs. (Author)
2001-03-01
K_#beta#/K_#alpha# X-ray intensity ratio following K-electron capture and radioisotope excitation
International Nuclear Information System (INIS)
The K_#beta#/K_#alpha# X-ray intensity ratios are measured for Mn and Fe and for six other elements with Z lying in the range 49<=Z<=82 following electron capture decay and photon excitation using "2"4"1Am and "5"7Co sources. High-resolution Si(Li) and HpGe detector systems were used in the experiments. The dependence of K_#beta#/K_#alpha# values on the mode of excitation in the case of Mn and Fe is attribuited to the chemical effects, while no such dependence is found for the high-Z elements.
1987-01-01
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
2003-01-01
Inelastic scattering of electrons by close-lying levels of isomeric nuclei
Energy Technology Data Exchange (ETDEWEB)
The process of inelastic scattering of hot plasma electrons with energies upto 3 keV by a pair of close-lying nuclear levels (..delta../ital E/less than or equal to2keV), one of whichis isomeric, is discussed. The transition cross sections in the nuclei/sup 242/Am, /sup 171/Lu, and /sup 73/Se are calculated. Estimates of the numberof isomeric nuclei de-excited as a result of electron-stimulated processes in aplasma with parameters characteristic of present-day experiments in controlledthermonuclear fusion are given.
1988-11-01
British Library Electronic Table of Contents (United Kingdom)
We operate a new NEC 250kV single-stage accelerator mass spectrometer (SSAMS) next to our established 5MV tandem. This permits good comparison of 14C-AMS and challenges SSAMS performance. Initial SSAMS ion-optical deficiencies have been addressed by shimming the injection magnet and 3permil 14C/13C measurement with background limited by sample chemistry is routine. Higher-precision analysis is also achievable. A problematic measurement interference remains, however. The small spectrometer was procured to add measurement capacity, and for experiments with positive ions, but is now the preferred instrument for both convenience and measurement quality.
2010-01-01
Heating and cooling with the building mass; Mit der Gebaeudemasse heizen und kuehlen
Energy Technology Data Exchange (ETDEWEB)
A Paderborn group of builder-owners decided in favour of so-called concrete core activation or isothermal component tempering as an alternative to conventional air conditioning. Results are now available for the first year of operation. [German] Am eigenen Neubau hat eine Paderborner Bauherrengemeinschaft die sogenannte Betonkernaktivierung - oder wie es die Bauherren nennen, isotherme Baukoerpertemperierung - als Alternative zu einer konventionellen Klimaanlage installiert. Inzwischen liegen die Messergebnisse von der ueber einjaehrigen Betriebszeit vor. (orig.)
2000-08-01
Gastrointestinal absorption of transuranic elements by rats
International Nuclear Information System (INIS)
Absorption of ''organically bound'' "2"3"3U and "2"4"1Am from gastrointestinal tracts of adult rats was twice that of the inorganic nitrate form. There was no difference between transport of "2"3"2U and "2"3"3U by adult rats, but "2"3"2U absorption by newborn rats was four times that of "2"3"3U. Absorption of "2"3"8Pu nitrate through the gut of the newborn is relatively insensitive to dose but incorporation in the gut mucosa saturates at high dose levels. Absorption of "2"3"8Pu is greater at 4 hr of age than at 24 hr.
1977-05-01
Energy Technology Data Exchange (ETDEWEB)
This digest paper presents the theoretical project of a fission engine for space ship as imagined by Y. Ronen from the Ben-Gourion Univ. (Israel). In this engine, the combustion chamber is covered with metastable {sup 242}Am thin sheets. The fission reaction is triggered with a bombardment of neutrons and the fission fragments ionize a gas (hydrogen, for instance) which is overheated and ejected through the engine nozzle. (J.S.)
2002-01-01
Decontamination of Johnston Island Coral: a preliminary study
International Nuclear Information System (INIS)
A preliminary investigation was completed on the characterization and decontamination of coral samples from Johnston Island. These samples were found to contain individual particles (2 to 0.25 mm) of contaminated coral as well as a piece of contaminated magnetic metal. They ranged in activity from about 70 to 811 nCi Am-241. The decontamination methods investigated were froth flotation, ferrite treatment, attrition scrubbing, ultrasonic treatment and dry sieving. Dry sieving, the more effective technique, separated about 42 wt % of the coral into a decontaminated fraction. This fraction (>4 mm) contained about 0.5% of the total activity. 7 refs., 3 tabs.
International Nuclear Information System (INIS)
A radioactively contaminated marine sediment core stemming from Irish Sea has been characterized by radiometric and mass spectrometric techniques as for "2"3"7Np, "2"4"1Am, "2"3"9Pu, "2"4"0Pu, "2"4"1Pu, "1"3"7Cs and "1"5"4Eu. The data obtained with independent methods in the framework of a QA/QC program as compared with the source term discharges, as well as with those reported in literature, are in good agreement. (author)
2005-02-01
Energy Technology Data Exchange (ETDEWEB)
The use of the method is described on powder samples before and after sintering with a La content of up to 1%. For excitation of the K series of La a /sup 241/Am source with an activity of 1.11 GBq was used. The obtained results showed that the method is sufficiently accurate (error 7%) at a short period of measurement (100 s). It gives satisfactory results even in the comparison of the experimental relative count rate and the theoretically calculated value despite the fact that the analytical signal comes from the sample surface.
1983-05-01
International Nuclear Information System (INIS)
The use of the method is described on powder samples before and after sintering with an La content of up to 1%. For excitation of the K series of La a _2_4_1Am source with an activity of 1.11 GBq was used. The obtained results showed that the method is sufficiently accurate (error 7%) at a short period of measurement (100 s). It gives satisfactory results even in the comparison of the experimental relative count rate and the theoretically calculated value despite the fact that the analytical signal comes from the sample surface. (Ha).
1983-01-01
British Library Electronic Table of Contents (United Kingdom)
Activity concentrations of some anthropogenic radionuclides (90Sr, 137Cs, 238Pu, 239+240Pu and 241Am) have been measured in the surface of marine sediments along the Saudi coast of the Arabian (Persian) Gulf. The samples were collected at different locations and water depths. The spatial distribution of the concentrations of the measured radionuclides showed a heterogeneous pattern and is independent of location or water depth. The obtained results are discussed and some conclusions are drawn.
2007-01-01
Sample requirements and design of an inter-laboratory trial for radiocarbon laboratories
International Nuclear Information System (INIS)
An on-going inter-comparison programme which is focused on assessing and establishing consensus protocols to be applied in the identification, selection and sub-sampling of materials for subsequent "1"4C analysis is described. The outcome of the programme will provide a detailed quantification of the uncertainties associated with "1"4C measurements including the issues of accuracy and precision. Such projects have become recognised as a fundamental aspect of continuing laboratory quality assurance schemes, providing a mechanism for the harmonisation of measurements and for demonstrating the traceability of results. The design of this study and its rationale are described. In summary, a suite of core samples has been defined which will be made available to both AMS and radiometric laboratories. These core materials are representative of routinely dated material and their ages span the full range of the applied "1"4C time-scale. Two of the samples are of wood from ...
2000-10-01
Magnetic resonance imaging of cerebral anomalies in subjects with resistance to thyroid hormone
Energy Technology Data Exchange (ETDEWEB)
Resistance to thyroid hormone (RTH) is an autosomal dominant disease caused by mutations in the human thyroid receptor beta gene on chromosome 3. Individuals with RTH have an increased incidence of attention deficit hyperactivity disorder (ADHD). The purpose of this study was to search for developmental brain malformations associated with RTH. Forty-three subjects (20 affected males [AM], 23 affected females [AF]) with resistance to thyroid hormone and 32 unaffected first degree relatives (18 unaffected males [UM], 14 unaffected females [UF]) underwent MRI brain scans with a volumetric acquisition that provided 90 contiguous 2 mm thick sagittal images. Films of six contiguous images beginning at a standard sagittal position lateral to the insula were analyzed by an investigator who was blind with respect to subject characteristics. The presence of extra or missing gyri in the parietal bank of the Sylvian fissure (multimodal association cortex) and multiple Heschl`s ...
1995-06-19
Highly enriched isotope samples of uranium and transuranium elements for scientific investigation
International Nuclear Information System (INIS)
The paper describes the production of highly enriched isotopes of uranium, plutonium, americium and curium by electromagnetic separation for scientific and applied researches in physics, chemistry, geology, medicine, biology and other fields. Using the equipment described, the isotopes are produced in quantities sufficient to set up nuclear physical experiments, to produce nuclear reference materials and standard sources for calibration of radiometrical and mass spectrometrical equipment, in radionuclide metrology, etc. For the following isotopes the indicated degrees of isotopic enrichment were achieved: "2"3"3U-99.97%; "2"3"5U-99.97%; "2"3"6U-98.0%; "2"3"8U-99.997%; "2"3"8Pu-99.6%; "2"3"9Pu-99.9977%; "2"4"0Pu-99.9-100%; "2"4"1Pu-96.998%; "2"4"2Pu-97.8-99.96%; "2"4"4Pu-96.7%; "2"4"1Am-99.6%; "2"4"2"mAm-73.6%; "2"4"3Am-99.2-99.94%; "2"4"3Cm-99.99%; "2"4"5Cm-99.998%; "2"4"6Cm-99.8%; "2"4"7Cm-90%, "2"4"8Cm-97%. Methods for ...
Energy Technology Data Exchange (ETDEWEB)
Since the integrity of the containment penetrations was confirmed under accident management (AM) conditions in the former test, failure criteria tests and aerosol trapping tests were carried out using low-voltage modules and flange gaskets of an actual plant under severe accident (SA) conditions, without AM. The safety margin for failure temperature of the penetrations and the credit for fission product (FP) aerosol trapping effect along the leakage paths of the degraded penetrations were evaluated in the present tests. Failure temperature of the penetrations ranged from 270 to 300degC for low-voltage modules and 300 to 350degC for flange gaskets under 0.4 to 1.0 MPa conditions. Pressure dependency on failure temperature was small. This means that the safety margin of failure temperature under AM condition is more than 70degC. By introducing a equivalent leak area for the damaged test pieces, total leak area was estimated ...
1999-07-01
Chelation of intracellular calcium blocks insulin action in the adipocyte
Energy Technology Data Exchange (ETDEWEB)
The hypothesis that intracellular Ca/sup 2 +/ is an essential component of the intracellular mechanism of insulin action in the adipocyte was evaluated. Cells were loaded with the Ca/sup 2 +/ chelator quin-2, by preincubating them with quin-2 AM, the tetrakis(acetoxymethyl) ester of quin-2. Quin-2 loading inhibited insulin-stimulated glucose transport without affecting basal activity. The ability of insulin to stimulate glucose uptake in quin-2-loaded cells could be partially restored by preincubating cells with buffer supplemented with 1.2 mM CaCl/sub 2/ and the Ca/sup 2 +/ ionophore A23187. These conditions had no effect on basal activity and omission of CaCl/sub 2/ from the buffer prevented the restoration of insulin-stimulated glucose uptake by A23187. Quin-2 loading also inhibited insulin-stimulated glucose oxidation and the ability of insulin to inhibit cAMP-stimulated lipolysis without affecting their basal activities. Incubation of cells with 100 ..mu..M ...
1987-02-01
Chelation of intracellular calcium blocks insulin action in the adipocyte
International Nuclear Information System (INIS)
The hypothesis that intracellular Ca"2"+ is an essential component of the intracellular mechanism of insulin action in the adipocyte was evaluated. Cells were loaded with the Ca"2"+ chelator quin-2, by preincubating them with quin-2 AM, the tetrakis(acetoxymethyl) ester of quin-2. Quin-2 loading inhibited insulin-stimulated glucose transport without affecting basal activity. The ability of insulin to stimulate glucose uptake in quin-2-loaded cells could be partially restored by preincubating cells with buffer supplemented with 1.2 mM CaCl_2 and the Ca"2"+ ionophore A23187. These conditions had no effect on basal activity and omission of CaCl_2 from the buffer prevented the restoration of insulin-stimulated glucose uptake by A23187. Quin-2 loading also inhibited insulin-stimulated glucose oxidation and the ability of insulin to inhibit cAMP-stimulated lipolysis without affecting their basal activities. Incubation of cells with 100 #mu#M quin-2 or quin-2 ...
International Nuclear Information System (INIS)
Ab initio total energy calculations within the framework of density functional theory have been performed for atomic hydrogen and oxygen chemisorption on the (0001) surface of double hexagonal packed (dhcp) americium using a full-potential all-electron linearized augmented plane wave plus local orbitals method. Chemisorption energies were optimized with respect to the distance of the adatom from the relaxed surface for three adsorption sites, namely top, bridge, and hollow hcp sites, the ad-layer structure corresponding to the coverage of a 0.25 monolayer in all cases. Chemisorption energies were computed at the scalar-relativistic level (no spin-orbit coupling NSOC) and at the fully relativistic level (with spin-orbit coupling SOC). The two-fold bridge adsorption site was found to be the most stable site for O at both the NSOC and SOC theoretical levels with chemisorption energies of 8.204 eV and 8.368 eV respectively, while the three-fold hollow hcp adsorption site was found to be ...
2008-02-01
/sup 242/Am/sup m/ fission cross section
Energy Technology Data Exchange (ETDEWEB)
The neutron-induced fission cross section of /sup 242/Am/sup m/ has been measured over the energy region from 10/sup -3/ eV to approx.20 MeV in a series of experiments utilizing a linac-produced ''white'' neutron source and a monoenergetic source of 14.1 MeV neutrons. The cross section was measured relative to that of /sup 235/U in the thermal (0.001 to approx.3 eV) and high energy (1 keV to approx.20 MeV) regions and normalized to the ENDF/B-V /sup 235/U(n,f) evaluated cross section. In the resonance energy region (0.5 eV to 10 keV) the neutron flux was measured using thin lithium glass scintillators and the relative cross section thus obtained was normalized to the thermal energy measurement. This procedure allowed a consistency check between the thermal and high energy data. The cross section data have a statistical accuracy of approx.0.5% at thermal energies and in the 1-MeV energy region, and a systematic uncertainty of ...
1984-06-01
cap alpha. decay of fission isomers
Energy Technology Data Exchange (ETDEWEB)
The theory of ..cap alpha.. decay in first-order perturbation theory is presented. The theory is designed for a strongly deformed nucleus in an isomeric state which changes its deformation dynamically through decay from a very deformed to an almost spherical shape. It is shown that other channels are not coupled to the ..cap alpha.. channel in first-order perturbation theory. The collective degrees of freedom of the daughter nucleus are described by shape vibrational states, eigenstates of a Hamiltonian whose potential has two minima. The parent nucleus is described by dynamically coupling the vibrational degrees of freedom to the ..cap alpha..-particle motion and also taking rotations into account. The ..cap alpha.. particle is taken to be a point-like particle. The theory is applied to the ..cap alpha.. decay of the isomeric state of /sub 95//sup 242/Am.
1984-10-01
ZZ MCJEF22NEA.BOLIB, MCNP Cross Section Library Based on JEF-2.2
International Nuclear Information System (INIS)
1 - Description or function: Continuous energy cross-section data library for the Monte Carlo program MCNP based on the JEF-2.2 evaluated nuclear data library (ACE Format). Format: ACE Number of groups: Continuous energy Nuclides (107): H-1, H-2, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-nat, N-14, N-15, O-16, O-17, F-19, Na-23, Mg-nat, Al-27, Si-nat, Cl-nat, Ti-nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-60, Ni-61, Ni-62, Ni-64, Zr-90, Zr-91, Zr-92, Zr-94, Zr-96, Zr-nat, Nb-93, Mo-92, Mo-94, Mo-95, Mo-96, Mo-97, Mo-98, Mo-100, Mo-nat, Tc-99, Ru-101, Ru-102, Ru-104, Rh-103, Pd-105, Pd-107, Ag-109, I-129, Xe-131, Cs-133, Pr-141, Nd-143, Nd-145, Pm-147, Sm-147, Sm-149, Sm-150, Sm-151, Sm-152, Eu-153, Gd-154, Gd-155, Gd-156, Gd-157, Gd-158, Gd-160, Hf-174, Hf-176, Hf-177, Hf-178, Hf-179, Hf-180, Pb-nat, Bi-209, Th-232, U-234, U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-239bis, Pu-240, Pu-241, Pu-242, Am-241, ...
ZZ MCB63NEA.BOLIB, MCNP Cross Section Library Based on ENDF/B-VI Release 3
International Nuclear Information System (INIS)
1 - Description of program or function: Continuous energy cross-section data library for the Monte Carlo program MCNP based on the ENDF/B-VI Release 3 evaluated nuclear data library (ACE Format). Format: ACE; Number of groups: Continuous energy; Nuclides (107): H-1, H-2, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-nat, N-14, N-15, O-16, O-17, Na-23, Mg-nat, Al-27, Si-nat, Cl-nat, Ti-nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-60, Ni-61, Ni-62, Ni-64, Zr-90, Zr-91, Zr-92, Zr-94, Zr-96, Zr-nat, Nb-93, Mo-94, Mo-95, Mo-96, Mo-97, Mo-nat, Tc-99, Ru-101, Ru-102, Ru-104, Rh-103, Pd-105, Pd-107, Ag-109, I-129, Xe-131, Cs-133, Pr-141, Nd-143, Nd-145, Pm-147, Sm-147, Sm-149, Sm-150, Sm-151, Sm-152, Eu-153, Gd-154, Gd-155, Gd-156, Gd-157, Gd-158, Gd-160, Hf-174, Hf-176, Hf-177, Hf-178, Hf-179, Hf-180, Hf-nat, Pb-206, Pb-207, Pb-208, Bi-209, Th-232,U-233, U-234, U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241, ...
VIS harvesting unsymmetrical squaraine dye for dye-sensitized solar cells
British Library Electronic Table of Contents (United Kingdom)
An unsymmetrical squaraine dye which contains an arylamino group was synthesized and used in dye-sensitized solar cells. The molar extinction coefficient of the dye is 77793 M-1 cm-1. Because our synthesized molecule may have no diradical character or the contribution of the diradicaloid component to resonance is quite small, the newly designed squaraine dye has a maximum absorption at 546 nm in the visible region compared with the NIR squaraine sensitizers. Cyclic voltammetry and time dependent density function theory calculation were accomplished to scrutinize the sensitized performance of the dye. Meanwhile, the novel sensitizer has been used to sensitize nanocrystalline TiO2-based solar cell. Under standard global AM 1.5 solar conditions, the squaraine dye-sensitized cell gives a short...
2012-01-01
Total and spontaneous fission half-lives for uranium, plutonium, americium and curium nuclides
International Nuclear Information System (INIS)
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 "2"3"2"-"2"3"6","2"3"8U, for "2"3"6","2"3"8"-"2"4"2","2"4"4Pu, for "2"4"1","2"4"2"m","2"4"3Am, and for "2"4"2"-"2"4"8","2"5"0Cm. Values are presented for both spontaneous fission half-life and total half-life. Problems with reported uncertainties are also discussed. (author).
Total and spontaneous fission half-lives for americium and curium nuclides
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.
1985-01-01
Energy Technology Data Exchange (ETDEWEB)
Objective: To determine the reproductibility of three-dimensional volume and thickness measurements of the knee joint cartilage with MRI in volunteers. Methods: The knees of 7 healthy individuals (ages 23 to 58 yrs.) were sagitally imaged with a resolution of 2x0.31x0.31 mm{sup 3}, using a fat-suppressed FLASH-3 D sequence. The knee was repositioned in between replicate acquisitions, 6 data sets being obtained in each case. After semiautomatic segmentation and three-dimensional reconstruction of the cartilage, the thickness was determined independent of the original section orientation. The coefficient of variation for repeated volume measurements and the deviations of the maximal cartilage thickness values were calculated subsequently. Results: The mean variation of the cartilage volumes of the replicate measurements was 1.4% ({+-}0.8%) in the patella, 1.7% ({+-}1.5%) in the femur, 3.0% ({+-}1.2%) in the medial tibial plateau and 3.5% ({+-}2.0%) in the lateral tibial plateau. The ...
1997-12-01
Energy Technology Data Exchange (ETDEWEB)
The role of high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) in the diagnosis of preoperative and postoperative complications caused by acquired cholesteatomas will be described in this paper. The pre- and postoperative imaging of the temporal bone was performed with HRCT and MRI. HRCT and MRI were performed in the axial and coronal plane. MRI was done with T2 weighted and T1 weighted sequences both before and after the intravenous application of contrast material. All imaging findings were confirmed clinically or surgically. The preoperative cholesteatoma-caused complications depicted by HRCT included bony erosions of the ossicles, scutum, facial canal in the middle ear, tympanic walls including the tegmen tympani, and of the labyrinth. The preoperative cholesteatoma-caused complications depicted by MRI included signs indicative for labyrinthitis, and brain abscess. Postoperative HRCT depicted bony erosions caused by recurrent cholesteatoma, bony defects ...
2003-03-01
The investigations on K and L X-ray fluorescence parameters of gold compounds
British Library Electronic Table of Contents (United Kingdom)
The study aimed to determine the chemical effects on the K and L X-ray intensity ratios and the K and L X-ray production cross sections for gold compounds. The K shell fluorescence yields and L shell average yields were also investigated. The samples were excited by 59.5keV ?-rays from an 241Am annular radioactive source and 123.6keV ?-rays from a 57Co annular radioactive source. K and L X-rays emitted from samples were counted by an Ultra-LEGe detector with a resolution of 0.150keV at 5.9keV. The experimental values were compared with theoretical, the semi-empirical and other experimental values.
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
Biosorption behaviour of and toxic effects of heavy metals in submersed and immobilised microorganisms was studied in batches and in continuous processes in an airlift-recycle reactor. Nickel, cadmium, and zinc were used as heavy metals. (orig./VHE) [Deutsch] Am Beispiel einer Naphthalin-2-sulfonsaeure-abbauenden Kultur wurde das Biosorptionsverhalten und die toxische Wirkung von Schwermetallen auf submerse und immobilisierte Mikroorganismen im Batch-Ansatz und im kontinuierlichen Betrieb in einem Airlift-Schlaufenreaktor untersucht. Als Schwermetalle wurden Nickel, Cadmium und Zink eingesetzt. (orig./VHE)
1993-09-01
Stentgraftimplantationen im Aortenbogen
British Library Electronic Table of Contents (United Kingdom)
Zusammenfassung Hintergrund Endograftimplantationen im oder am Aortenbogen stellen besondere Herausforderungen an die Implantationstechnik und an die mechanischen Eigenschaften von Stentgrafts und ihren Einf?hrungssystemen, bedingt durch die Notwendigkeit, die Prothesen punktgenau abzusetzen und durch die mit der Biegung im Aortenbogen zunehmende Reibungswiderst?nde innerhalb der Einf?hrungssysteme. Die Endograftsysteme der 1. Generation (Talent?, Zenith TX 1?, TAG?) zeigten in dieser Lokalisation technisch bedingte Limitationen. Neue Prothesen Bei den seit 2004 und 2005 verf?gbaren neuen Stentgrafts (E-vita?, Zenith TX 2?, Valiant?, Relay?) sind diese Limitationen weitgehend ?berwunden. Durch technische Verbesserungen von Stentgrafts und Einf?hrungssystemen ist es nun m?glich, auch lange ...
2006-01-01
Energy Technology Data Exchange (ETDEWEB)
So far, publications in turbomachinery engineering have tended to neglect the description of control systems and strategies which could be converted into practical guidelines for turbine operation. The contribution describes the power station turbine as a basis for modelling the control stage. The solutions will serve as a basis for further type-specific investigations of the problem. [German] Eine vornehmlich regelungstechnisch ausgerichtete Beschreibung des thermodynamisch-mechanischen Wirkungsgeschehens im Bereich der Regelstufe von Dampfturbinen sowie deren Umsetzung in schluessige, betriebsrelevante Aussagen fehlen bislang in der Turbomaschinenliteratur. Im Beitrag werden am Beispiel der Kraftwerksturbine die Grundlagen fuer eine modelltechnische Nachbildung der Regelstufe entwickelt. Die Loesungen dienen als Ausgangsbasis fuer weitere typenspezifische Bearbeitungen dieses Problems. (orig.)
2000-07-01
Solvothermal Synthesis of a New Photochromic Azo Polymer and its Self-assembly Behavior
British Library Electronic Table of Contents (United Kingdom)
An amphiphilic azobenzene diblock copolymer {2-[4-(4-methoxy phenyl azo)phenoxy]hexyl acrylate co-acrylic acid} was synthesized via reversible addition-fragmentation chain transfer polymerization in a hydrothermal reactor. The products were characterized by 1H-NMR, DSC, GPC and UV-Vis spectroscopy. Different self-assembly behaviors of this amphiphilic diblock copolymer in different organic solvent with different water content were investigated. In THF/H2O solution, the diblock copolymer self-assembled into spheres and the spheres would then change to vesicles with smaller size by increasing the volume of H2O. However, in DMSO/H2O solution, the sizes and morphologies of the self-assembled spheres would not change significantly with an enhanced amount of H2O. Photochromic behaviors of the am...
2010-01-01
Serological testing-An alternative to boosters?
British Library Electronic Table of Contents (United Kingdom)
The issue of the duration of immunity, particularly for the modified live viral components of veterinary vaccines, has been a significant part of the recent vaccination debate. One manufacturer has increased the recommended booster interval for these components to 3 years give name and another now states `up to 4 years' immunity.There remain many unanswered questions regarding this duration of immunity (DOI). Studies suitable for data sheet claims are time consuming and costly and can only be performed in laboratory dogs under tightly controlled conditions. Evidence from rabies serology testing in the UK shows that the response of individual animals to routine vaccination is highly variable. Much of the published field evidence on the persistence of antibody titres originates from North Am...
2006-01-01
British Library Electronic Table of Contents (United Kingdom)
Abstract Root exudates play a major role in the mobilization of sparingly soluble nutrients in the rhizosphere. Since the amount and composition of major metabolites in root exudates from one plant species have not yet been systematically compared under different nutrient deficiencies, relations between exudation patterns and the type of nutrient being deficient remain poorly understood. Comparing root exudates from axenically grown maize plants exposed to N, K, P, or Fe deficiency showed a higher release of glutamate, glucose, ribitol, and citrate from Fe-deficient plants, while P deficiency stimulated the release of -aminobutyric acid and carbohydrates. Potassium-starved plants released less sugars, in particular glycerol, ribitol, fructose, and maltose, while under N deficiency lower am...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The behavior of Am, Cm, Bk, Cf, Es, and other actinides, as well as Zr, on anion and cation exchangers in aqueous and water-ethanol solutions of sulfuric acid as a function of the various components of the solution has been investigated. It has been discovered that the presence of ethanol in sulfuric acid solutions causes an increase in the distribution coefficients both on cation exchangers and on anion exchangers. The possibility of the use of ion exchangers for the preconcentration and separation of transplutonium elements from U, Np, Pu, Zr, and other elements which form strong complexes with sulfate ions over a broad range of concentrations of sulfuric acid has been demonstrated.
1988-05-01
Radio and television interference caused by corona discharges from high-voltage transmission lines
Energy Technology Data Exchange (ETDEWEB)
Increase in power utility loads in industrialized countries, as well as developing countries, demands a higher level of transmission line voltage. Radio interference (RI) problems have been determined to be a limiting factor in selecting the size of transmission line conductors. Transmission line noise is primarily caused by corona discharges in the immediate vicinity of the conductor. It has been observed that discharges occur during both half-cycles of the applied voltage, but positive corona is usually predominant at AM radio frequencies range with practical high-voltage and extra high-voltage transmission lines. The corona radio noise effect is highly dependent upon the presence of particles on the surface of the conductor and the increase of the electrical gradient beyond the breakdown value of the air. Therefore, corona radio noise varies significantly with the weather and atmospheric conditions and generally increases by 10 to 30 dB in foul weather.
1996-11-01
Radio and television interference caused by corona discharges from high-voltage transmission lines
Energy Technology Data Exchange (ETDEWEB)
Increase in power utility loads in industrialized countries, as well as developing countries, demands a higher level of transmission line voltage. Radio interference (RI) problems have been determined to be a limiting factor in selecting the size of transmission line conductors. Transmission line noise is primarily caused by corona discharges in the immediate vicinity of the conductor. It has been observed that discharges occur during both half-cycles of the applied voltage, but positive corona is usually predominant at AM radio frequencies range with practical high-voltage and extra high-voltage transmission lines. The corona radio noise effect is highly dependent upon the presence of particles on the surface of the conductor and the increase of the electrical gradient beyond the breakdown value of the air. Therefore, corona radio noise varies significantly with the weather and atmospheric conditions and generally increases by 10 to 30 dB in foul weather.
1995-10-01
Radio and television interference caused by corona discharges from high-voltage transmission lines
International Nuclear Information System (INIS)
Increase in power utility loads in industrialized countries, as well as developing countries, demands a higher level of transmission line voltage. Radio interference (RI) problems have been determined to be a limiting factor in selecting the size of transmission line conductors. Transmission line noise is primarily caused by corona discharges in the immediate vicinity of the conductor. It has been observed that discharges occur during both half-cycles of the applied voltage, but positive corona is usually predominant at AM radio frequencies range with practical high-voltage and extra high-voltage transmission lines. The corona radio noise effect is highly dependent upon the presence of particles on the surface of the conductor and the increase of the electrical gradient beyond the breakdown value of the air. Therefore, corona radio noise varies significantly with the weather and atmospheric conditions and generally increases by 10 to 30 dB in foul weather.
1996-04-09
Prospects of wind energy in Bangladesh
Energy Technology Data Exchange (ETDEWEB)
Wind speed has been measured in Patenga, Cox`s Bazar, Kuakata, Moheshkhali, and Noakhali by the computerized anemometers. The wind computers have been installed at 20 meters height. According to this study annual average wind speeds in the coastal regions of Bangladesh are greater than 6.5 m/s at the height of 20 meters. It has been observed that during day times (8 a.m. to 7 p.m.) wind speeds are about 30 to 40% higher than the average values. The value of the power exponent {alpha} has been determined in the above sites and it is 0.139. So, at 40 meters height the annual average wind speed is about 7.15 m/s. So, wind speeds in the coastal regions of Bangladesh are suitable for both water pumping and electricity generation. Details are given in this paper with graphical and analytical representations. (author)
1996-09-01
Production of plutonium, yttrium and strontium tracers for using in environmental research
International Nuclear Information System (INIS)
Summary of cyclotron production methods of "2"3"7Pu (45,2 d), "8"8Y (106,65 d) and "8"5Sr (64,84 d) tracers via nuclear reactions with protons and alphas on "2"3"5U, "8"8Sr and "8"5Rb targets in wide energy range is given. Chemical methods of separation and purification of the tracers from the irradiated uranium, strontium and rubidium targets are described. The tracers were used for determination of Pu (239-240), Sr-90 and Am-241 in the samples (soil, plants, underground waters) from Semipalatinsk Test Site. Obtained results are discussed.
2001-12-12
Particle identification for heavy ions in a time-of-flight spectrometer
Energy Technology Data Exchange (ETDEWEB)
A time-of-flight (TOF) spectrometer has been constructed at the JAERI 20 MV tandem accelerator facility. A position-sensitive start detector, which consists of a thin carbon foil, microchannel plates and a resistive plate, was developed for the TOF measurements through the spectrometer. The time and position resolutions obtained were 120 ps and 0.3 mm for ..cap alpha.. particles from /sup 241/Am, respectively. A two-dimensional position-sensitive detector was also developed to measure the solid angle of the spectrometer and the maximum solid angle obtained was 9.5 msr. As a particle detector a Bragg curve ionization chamber was developed. From the Bragg curves of heavy ions in the detector, energies, ranges and Bragg curve peaks were measured and used for particle identification. The resolving power Z/..delta..Z of the atomic number was about 50.
1982-05-01
Energy Technology Data Exchange (ETDEWEB)
The K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios are measured for Mn and Fe and for six other elements with Z lying in the range 49 less than or equal to Z less than or equal to 82 following electron capture decay and photon excitation using /sup 241/Am and /sup 57/Co sources. High-resolution Si(Li) and HpGe detector systems were used in the experiments. The dependence of K/sub ..beta..//K/sub ..cap alpha../ values on the mode of excitation in the case of Mn and Fe is attributed to chemical effects, while no such dependence is found for the high-Z elements.
1987-01-01
Instruments for X-ray fluorescence analysis and spectrometry
International Nuclear Information System (INIS)
The radionuclide X-ray fluorescence analyzer consists of a source changer and a sample changer. "5"5Fe, "1"0"9Cd and "2"4"1Am are used as excitation sources. The radiation is detected with a semiconductor Si(Li) detector. The complete assembly of the apparatus consists of an imagine unit, a keyboard, a floppy disc drive, a printer, a console and a rack with analog and digital electronics. Its multichannel amplitude analyzer consists of power supplies, a high voltage supply, a linear amplifier, an analog-to-digital converter and a computer. The technical specifications are given. The control and data processing system is controlled with an MHB 8080A microprocessor. Software for semiconductor gamma spectrometry and for quantitative gamma spectrometry will be supplied with the equipment. (E.S.). 3 figs., 4 refs.
Energy Technology Data Exchange (ETDEWEB)
A passive dosemeter, based on a Makrofol ED track detector covered with aluminized Mylar, enclosed in diffusion chamber, has been used for radon concentration studies. Detectors have been irradiated, using a {sup 241}Am source, at different energies and fluences in order to obtain the electrochemical etching conditions that allow the optimum registration of alpha particles having energies over 3 MeV. Thirty dosemeters have been sent to the UK National Radiation Protection Board (NRPB) Radon Environmental Chamber for calibration. The sensitivity of the dosemeter has been calculated. Several dosemeters have also been exposed in houses and dwellings in the Barcelona and Madrid areas for monitoring. Values for radon concentration in the areas under study are presented. (author).
1991-01-01
International Nuclear Information System (INIS)
A passive dosemeter, based on a Makrofol ED track detector covered with aluminized Mylar, enclosed in diffusion chamber, has been used for radon concentration studies. Detectors have been irradiated, using a "2"4"1Am source, at different energies and fluences in order to obtain the electrochemical etching conditions that allow the optimum registration of alpha particles having energies over 3 MeV. Thirty dosemeters have been sent to the UK National Radiation Protection Board (NRPB) Radon Environmental Chamber for calibration. The sensitivity of the dosemeter has been calculated. Several dosemeters have also been exposed in houses and dwellings in the Barcelona and Madrid areas for monitoring. Values for radon concentration in the areas under study are presented. (author).
Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. Several signatures, ranging from the positron excess, as observed by HEAT, AMS-01 and PAMELA, the gamma ray excess, as observed by the EGRET spectrometer, the WMAP-haze, and constraints from antiprotons, as observed by CAPRICE, BESS and PAMELA, have been discussed in the literature. Unfortunately, the different signatures all lead to different WIMP masses, indicating that at least some of these interpretations are likely to be incorrect. Here we review them and discuss their relative merits and uncertainties. New x-ray data from ROSAT suggests non-negligible convection in our Galaxy, which leads to an order of magnitude uncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in the halo to outer space.
2008-01-01
Energy Technology Data Exchange (ETDEWEB)
Contamination and blockages of the cooling tubes in the turbine condenser disturb the heat transfer, thereby causing power losses at the turbine and increasing the fuel demand. Corrosions cause tubing leakages which require operating downtimes and reduce the lifetime of the pipes. Tube cleaning systems and backflushing cooling water filters eliminate these problems. Nevertheless it can come to coatings in the condenser tubes, if the tube cleaning equipment does not operate optimally or if coarse dirt is entered. Under this aspect, the author of the contribution under consideration reports on these problems on the basis of practical examples. The author gives references to the optimized operation of the tube cleaning system and the cooling water filtration.
2010-07-01
Energy Technology Data Exchange (ETDEWEB)
A number of concrete culverts used to retrievably store drummed, dry, radioactive waste at the Savannah River Site (SRS), were suspected of containing ambiguous quantities of transuranic (TRU) nuclides. These culverts were assayed in place for Pu-239 content using thermal and fast neutron counting techniques. High resolution gamma-ray spectroscopy on 17 culverts, having neutron emission rates several times higher than expected, showed characteristic gamma-ray signatures of neutron emitters other than Pu-239 (e.g., Pu-238, Pu/Be, or Am/Be neutron sources). This study confirmed the Pu-239 content of the culverts with anomalous neutron rates and established limits on the Pu-239 mass in each of the 17 suspect culverts by in-field, non-intrusive gamma-ray measurements.
1990-01-01
Energy Technology Data Exchange (ETDEWEB)
A number of concrete culverts used to retrievably store drummed, dry, radioactive waste at the Savannah River Site (SRS), were suspected of containing ambiguous quantities of transuranic (TRU) nuclides. These culverts were assayed in place for Pu-239 content using thermal and fast neutron counting techniques. High resolution gamma-ray spectroscopy on 17 culverts, having neutron emission rates several times higher than expected, showed characteristic gamma-ray signatures of neutron emitters other than Pu-239 (e.g., Pu-238, Pu/Be, or Am/Be neutron sources). This study confirmed the Pu-239 content of the culverts with anomalous neutron rates and established limits on the Pu-239 mass in each of the 17 suspect culverts by in-field, non-intrusive gamma-ray measurements.
1990-12-31
Engagement for progress: applied philosophy of science in context
British Library Electronic Table of Contents (United Kingdom)
Philosophy of science was once a much more socially engaged endeavor, and can be so again. After a look back at philosophy of science in the 1930s?1950s, I turn to discuss the current potential for returning to a more engaged philosophy of science. Although philosophers of science have much to offer scientists and the public, I am skeptical that much can be gained by philosophers importing off-the-shelf discussions from philosophy of science to science and society. Such efforts will likely look like efforts to do applied ethics by merely applying ethical theories to particular contexts and problems. While some insight can be gained by these kinds of endeavors, the most interesting and pressing problems for the actual practitioners and users of science are rarely addressed. Instead, I recom...
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
A study was undertaken to assess the effect of different storage temperatures on senescence and postharvest performance of isolated flowers of Ranunculus asiaticus L.. The main aim of the work was to develop a cost-effective storage protocol to reduce the postharvest losses and to bring out the transportation of cut flowers of R. Asiaticus. The flowers were subjected to two different storage treatments, dry storage and wet storage, and their postharvest performance was compared under laboratory conditions. For this purpose, the buds were harvested at 8:00 AM at loose bud stage (Stage II of flower development). The harvested buds were cut to a uniform size of 15 cm and processed for dry or wet storage. For dry storage, the buds were packed after wrapping them in moistened filter papers and ...
2011-01-01
Effect of Nordic diets on ECOSYS model predictions of ingestion doses
British Library Electronic Table of Contents (United Kingdom)
The ECOSYS model is used to estimate ingestion dose in the ARGOS and RODOS decision support systems for nuclear emergency management. It is recommended that nation-specific values for several parameters are used in the model. However, this is generally overlooked when the systems are used in practice. We have estimated first year ingestion doses in two scenarios with wet and dry deposition of 137Cs, using the ECOSYS model. We calculated doses for each country using national dietary data while keeping all other parameters at their default values. These dose calculations were then used to estimate the variation in ingestion doses resulting from the variation in the diets only. The dietary data demonstrated that the average consumption of milk, meat and vegetables varied by a factor of 2-4 am...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: With intracranial tumors a flat, contrast-enhancing, probably dural structure adjacent to the tumor can occasionally be observed on gadolinium-DTPA enhanced MR images. Therefore we have attempted to evaluate a tumor infiltration of this enthancement on MRI. Material and Methods: This study included 50 patients. 19 patients had a dural thickening at the tumor base (13 meningiomas and 6 metastases), while 31 patients did not (12 meningiomas and 19 metastases). Studies included plane T{sub 2}-weighted spin echo (SE) images as well as T{sub 1}-weighted axial, coronal, or sagittal plains with and without contrast agent. Histopathological examinations, were done on the tumor base adjacent to the dura mater. Results: 7 of 12 meningiomas showed a meningeal thickening on MRI with histopathologically proven tumor infiltration as did also 5 of 6 metastases. But 3 of 12 meningiomas and 15 of 19 metastases without dural thickening at the tumor base also showed tumor invasion into the dura ...
1997-11-01
Energy Technology Data Exchange (ETDEWEB)
The present work focuses on investigations of a highly selective ligand for Am(III)/Ln(III) separation: bis-triazinyl-pyridine (BTP). By means of nano-electro-spray mass spectrometry, complex formation of BTP with selected elements of the lanthanide series is investigated. We show that the diluent drastically influences complex speciation. Measurements obtained in the extraction-relevant diluent 1-octanol show the occurrence of Ln(BTP){sub i} (i 1-3) species in different relative abundances, depending on the lanthanide used. Here, the relative abundances of the Ln(BTP){sub 3} complexes correlate with the distribution ratios for extraction to the organic phase of the respective lanthanide. (authors)
2009-12-15
Development of anion-exchange resins for separations of actinides
Energy Technology Data Exchange (ETDEWEB)
The evolution of these new ion-exchange resins hinges upon an understanding of the chemistry of actinide metal complexes as they exist in solution and when interacting with the cationic sites. Molecular modeling of electrostatic interactions between the metal complex and the cationic substrate is used to help visualize uptake mechanisms and, eventually, to predict optimized coordination sites. Thus, these new materials integrate the fields of ion-specific chelation and ion-exchange technology. Synthesized resins contain cationic sites designed to facilitate the uptake of plutonium nitrato complexes from high-nitrate solutions, and they exhibit distribution coefficients that are up to 10 times higher than those observed for commercial resins. Additionally, some new resins show surprisingly large Kd`s for anionic complexes of Am(III) and U(VI).
1997-12-31
Energy Technology Data Exchange (ETDEWEB)
The measurements of the K X-ray intensity ratio I(K{sub {beta}})/I(K{sub {alpha}}) for the 17 elements Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Y, Zr, Nb and Mo have been done following ionization by 59.5keV {gamma}-rays from a {sup 241}Am point source. Ratios of emission probabilities of Auger electrons and the vacancy transfer coefficients have been extracted in terms of the intensity ratios. It is found that the present results agree well with earlier fitted values and the semi-empirical values.
2006-01-15
Determination of Proper Peaking Time for Ultra Lege detector at Medium Energies
International Nuclear Information System (INIS)
Reducing count losses and pile-up pulse effects in quantitative and qualitative analysis is necessary for accuracy of analysis. Therefore, the optimum peaking time for particular detector systems is important. For this purpose, pure Se and Zn elements were excited by 59.5 keV ?-rays from a 50 mCi 241Am annular radioactive source in this study. The characteristic x-rays emitted from pure Se and Zn elements were detected by using an ultra low energy Ge (Ultra-LEGe) detector connecting Tennelec TC 244 spectroscopy amplifier at different peaking time modes. Overall pulse widths were determined by HM 203-7 oscilloscope connecting amplifier. The proper peaking time for ultra low energy germanium detector (Ultra-LEGe) is determined about 4 ?s.
2008-08-25
Constitutional examinations in the system Fe-Al-Zr; Konstitutionsuntersuchungen im System Fe-Al-Zr
Energy Technology Data Exchange (ETDEWEB)
Two isothermal sections were prepared at 1000 and 1150 C showing the low-Zr phases of the system Fe-Al-Zr. The phase equilibria were determined by means of X-ray powder diffractometry and electron beam microanalysis. For initial characterisation of mechanical properties, hardness values are determined and added to the tabulated data. (orig./MM) [German] Es werden am Fe-Al-Zr-System zwei isotherme Schnitte durch den zirkoniumarmen Teil des Systems bei 1000 und 1150 C erstellt. Die auftretenden Phasengleichgewichte werden mit Hilfe der Roentgenpulverdiffraktometrie und Elektronenstrahlmikroanalyse aufgeklaert. Zusaetzlich werden zur ersten Charakterisierung der mechanischen Eigenschaften Haertewerte bestimmt.
1999-07-01
Energy Technology Data Exchange (ETDEWEB)
CT and MRI of acquired abnormalities of the inner ear and cerebello-pontine angle present themselves with very typical findings. The imaging should be adapted to the pathology looked for and either CT or MRI should be used alone or in combination.CT, especially high resolution CT (HRCT), provides an excellent bone contrast, while MRI has a much superior soft tissue contrast. Acute inflammatory changes of the inner ear are solely depicted by contrast-enhanced MRI. HRCT excellently depicts osseous changes of the inner ear and cerebellopontine angle such as chronic ossifying labyrinthitis occurring after acute labyrinthitis, otosclerotic or traumatic changes. Tumorous changes not yielding to bony changes are best delineated by MRI. Posttraumatic hemorrhage and chronic fibrotic changes within the labyrinth are depicted by MRI, only. In conclusion HRCT and MRI are excellent methods to delineate acquired abnormalities of the inner ear and cerebello-pontine angle. HRCT best depicts osseous ...
2003-03-01
Comparative study of extraction methods for solar cell model parameters
Energy Technology Data Exchange (ETDEWEB)
A comparative study of three methods for extracting solar cell parameters of the single-diode lumped-circuit model is presented, using experimental characteristics collected from two silicon cells over a range of illuminations and temperatures. The results show that the curve-fitting method can often give erroneous parameter values. The 5-point methods are found to be reliable and accurate in situations where the model is a good approximation of cell performance. The analytical 5-point method, however, has the added advantage of simplicity. It is also found that for the cell measured, the single diode model is valid at illuminations above one-half AM1 but gives non-physical parameter values at lower illumination.
1986-03-01
Collection of athermal phonons into doped Ge thermistors using quasiparticle trapping
Energy Technology Data Exchange (ETDEWEB)
We have developed a low-temperature particle detector that uses a novel quasiparticle trapping mechanism to funnel athermal phonon energy from an 80 mg Ge absorber into a 1.6 mg doped Ge thermistor via a superconducting Al film. We report on pulse height spectra obtained at 320 mK by scanning a {sup 241}Am alpha source along the device, and show that up to 20% of the energy deposited in the Ge absorber by a 5.5 MeV alpha particle interaction can be collected into a thermistor via quasiparticle trapping. We show that this device is sensitive to the position of an alpha particle interaction in the Ge absorber for interaction distances of up to 5 mm from a quasiparticle trap.
1995-05-15
CTH-process for HLLW treatment. Pt. 1
Energy Technology Data Exchange (ETDEWEB)
A process for separation of actinides and technetium from reprocessing high level liquid waste has been developed, the CTH-process. The main parts are three consecutive solvent extraction cycles followed by an optional step for sorption on inorganic ion exchangers. The first extraction cycle removes and recovers uranium, neptunium, and plutonium by extraction with HDEHP. The second extraction cycle separates technetium and nitric acid from the waste using TBP. In the third extraction cycle Am and Cm are separated from the waste using HDEHP. The actinide free waste is then passed through inorganic ion exchangers to remove most of remaining radionuclides. The process has been tested on an authenic HLLW solution. A decontamination factor > 10/sup 5/ for alpha emitters was measured for the solvent extraction process and the sorption on inorganic ion exchangers gave a decontamination factor > 3x10/sup 4/ for beta emitters.
1984-01-01
Burning ice. Methane hydrate on the sea floor; Brennendes Eis. Methanhydrat am Meeresgrund
Energy Technology Data Exchange (ETDEWEB)
In certain regions of the sea floor, water and methane from organic depositions have turned into a burnable form of ice, i.e. methane hydrates which contain more stored energy than all fossil fuel reserves. If they should desintegrate as a result of global heating, methane will be released and will contribute to further global heating. [Deutsch] Im Boden bestimmter Meeresregionen haben sich Wasser und Methan aus organischen Ablagerungen zu einer brennbaren Form von Eis vereinigt. Diese Methanhydrate speichern mehr Energie als alle fossilen Brennstoffvorraete. Wenn sie sich bei einer globalen Erwaermung zersetzen, koennte das entweichende Methan als Treibhausgas die Erde noch mehr aufheizen. (orig.)
1999-06-01
Bragg Curve Counter for primary beam monitor
Energy Technology Data Exchange (ETDEWEB)
The prototype Bragg Curve Counter (BCC) has been tested by {alpha}-source ({sup 241}Am) with a continuous gas flow system (P-10: 90% Ar+10% CH{sub 4}, at 300Torr). Two types of the Frisch grid were prepared for the BCC. One was made of expanded metal meshes, which consist of 175 meshes/inch{sup 2} with a 100{mu}m{sup t} nickel sheet. The other was made of a 1mm pitch wire with {phi} 50 {mu}m of the tungsten. The shape of Bragg peak signal was compared each other. It was found that the energy spectrum obtained by the wire grid is a little sharper than that obtained by the meshes grid. However the meshes grid is superior than the wire grid so far as handling and durability are concerned. (author).
1994-12-31
International Nuclear Information System (INIS)
The problems are discussed of using radionuclide X-ray fluorescence analysis (the most frequently used source is "2"4"1Am) and neutron activation analysis for monitoring the chemical quality of the working environment of a welder. Elements determinable by these methods are listed and the advantages of the methods stated with regard to speed, simplicity and appropriate accuracy of measurement together with commercial availability of the instruments. Welding as a source of harmful substances is assessed by determination of the amount of chromium in aerosols generated by welding austenitic chromium-nickel steels. The described methods allow to obtain a complex image of the chemical nature of welding aerosols and to understand the mechanism of their impact on the human organism. (J.C.).
1986-01-01
Air pollution abatement at the crossroads. Emissionsminderungstechnik am Scheideweg
Energy Technology Data Exchange (ETDEWEB)
A brief survey of present air pollution abatement requirements relevant to domestic heating systems is followed by a comparative evaluation of the latest results worked out on the part of boiler and burner manufacturers, and the legal requirements and existing regulations. Details are given on the limiting values required by law, the regulations valid for domestic heating systems, and the values fixed according to scientific knowledge and research results (development of NO{sub x} and CO, flame temperature dependence, table comparing CO and NO{sub x} limiting values for different types of burners and boilers). Access is given to primary air pollution abatement measures (cooling of flames, absorber rods, influence of mixing pressure), modern burner and boiler systems, and secondary measures suited for smaller boilers. (HWJ).
1989-05-01
British Library Electronic Table of Contents (United Kingdom)
? Introduction For large trees without a continuous sequence of growth rings in their trunk, such as the African baobab (Adansonia digitata L.), the only accurate method for age determination is radiocarbon dating. As of today, this method was limited to dating samples collected from the remains of dead specimens. ? Methods Our research extends significantly the dating of such trees to large live specimens with inner cavities. The new approach is based on collecting samples from the cavities and their subsequent radiocarbon dating. ? Results The giant two-stemmed Platland tree, also known as Sunland baobab, was investigated by using this new approach. AMS radiocarbon dates of the oldest sample segments originating from the two inner cavities indicate that the large stem I (364.5?m3) is 750...
2011-01-01
A novel BMT technique for treatment of various currently intractable diseases
British Library Electronic Table of Contents (United Kingdom)
A recently-developed BMT method combines a ''Perfusion Method'' (PM) for collecting bone marrow cells (BMCs) with the Intra-Bone Marrow (IBM) injection of BMCs (IBM-BMT). As distinct from the conventional aspiration method (AM), the PM allows rapid (within 1 h) collection of BMCs without T cell contamination (T cells < 10%). Therefore, no GvHD occurs. Moreover, the burden on donors, such as back pain, bleeding and infection, can be reduced. Full chimerism can be achieved even with only mild conditioning regimens if IBM-BMT is carried out, since IBM-BMT replaces not only the recipient's hemopoietic stem cells (HSCs) but also mesenchymal stem cells (MSCs) with donor-derived HSCs and MSCs. Using this method, we show that most currently intractable diseases are HSC or MSC disorders, and that t...
2011-01-01
Understanding the peak asymmetry in alpha liquid scintillation with {beta}/{gamma} discrimination
Energy Technology Data Exchange (ETDEWEB)
The peak evaluation in alpha liquid scintillation is known to be easy, mostly due to the gaussian shape of the peaks. However, we often observed a high-energy tail in addition to a pure gaussian function. This effect is only detectable with a high resolution {alpha} liquid scintillation spectrometer such as the PERALS trademark system. Indeed, its intrinsic resolution (180 keV for a 4 MeV {alpha} particle) is better than that obtained for conventional LSC spectrometers. The peak asymmetry was quantified using the Fisher's coefficient {gamma}{sub 1} (symmetry factor). We show that the main effect responsible for the asymmetry is internal conversion. Indeed, most of the even-even nuclides have low {alpha} intensity transitions leading to excited levels of their daughter nuclides. The internal conversion is almost equal to 100% and consequently produces a sum peak at higher energy. No generalization is possible for odd-even nuclides, but the knowledge of their disintegration ...
2000-07-01
The generalized demodulation time-frequency analysis is a novel signal processing method, which is particularly suitable for the processing of multi-component amplitude-modulated and frequency-modulated (AM-FM) signals as it can decompose a multi-component signal into a set of single-component signals whose instantaneous frequencies own physical meaning. While fault occurs in gear, the vibration signals measured from gearbox would exactly display AM-FM characteristics. Therefore, targeting the modulation feature of gear vibration signal in run-ups and run-downs, a fault diagnosis method in which generalized demodulation time-frequency analysis and envelope order spectrum technique are combined is put forward and applied to the transient analysis of gear vibration signal. Firstly the multi-component vibration signal of gear is decomposed into some mono-component signals using the generalized demodulation time-frequency analysis approach; ...
2010-02-01
Energy Technology Data Exchange (ETDEWEB)
A study conducted at the IHS had the aim to obtain basic information on whether it is possible to build flow turbines following the free jet principle that are on a par with, or superior to, the conventional design, especially in terms of performance and the efficiency curve. Several inflow contours with a ventilated free jet and a conventional flow turbine were studied. The direct comparison of these variants revealed a slightly enhanced peak load efficiency and a very distinct superiority of the free jet contour during partial load. But the efficiency of all variants failed to attain the values claimed by commercial manufacturers. As compared to the initial contour, peak load efficiency was enhanced by 5 per cent. During partial load, the variants studied showed a distinct superiority of the free jet concept over the contour of conventional flow turbines. (orig.) [Deutsch] Am IHS wurde eine Untersuchung mit dem Ziel durchgefuehrt, grundlegende Aussagen zu ...
1997-12-31
Synthesis, structure and characterisation of the n=4 Aurivillius phase Bi5Ti3CrO15
International Nuclear Information System (INIS)
The n=4 Aurivillius phase, Bi5Ti3CrO15, was synthesised by solid state reaction. Rietveld analysis of high resolution neutron diffraction data demonstrated this material to adopt the polar space group A21am at room temperature, transforming to the aristotype I4/mmm structure above 650 oC. This phase transition is coincident with an anomaly in DSC signal and relative permittivity, which are characteristic of a ferroelectric-paraelectric phase transition. Bi5Ti3CrO15 exhibits paramagnetic behaviour at low temperature, with short range antiferromagnetic interactions, but no evidence for long range magnetic ordering. This is considered a consequence of significant disorder of Ti and Cr over the available octahedral sites, as demonstrated by analysis of neutron diffraction data. -- Graphical abstract: We report here the synthesis, structure and characterisation of the n=4 Aurivillius phase Bi5Ti3CrO15. Analysis of neutron powder diffraction and XANES data, supported by ...
2011-02-01
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 workability of the mixture ...
2006-03-01
International Nuclear Information System (INIS)
A processing technique for A-15 compounds which has improved mechanical and superconducting properties has been developed. This technique consists of rapid solidification of the alloy by the chill block spinning machine (CBSM) to form amorphous ribbons and by subsequent annealing crystallizes the stable or metastable fine grain flexible A-15 structure. The CBSM has been modified so that all the processing parameters could be controlled and optimized for each alloy composition. By the improved CBSM it was possible to form amorphous Nb_3Si, Nb_3Ge and Nb_3(AlSi) ribbons with more than 80% reproducible rate. Critical current density measurements are limited by contact resistance. A Cu plating technique was introduced in this research that made the contact resistance three orders of magnitude lower than that obtained by other methods. This plated coating also gave an additional mechanical support to the sample and acted as a shunt for thermal stabilization of the sample. J_c of Nb_3Ge at ...
Future needs and requirements for AMS "1"4C standards and reference materials
International Nuclear Information System (INIS)
"1"4C measurement uses a number of standards and reference materials with different properties. Historically the absolute calibration of "1"4C measurement was tied to 1890 wood, through the 'primary' standard of NBS-OxI (produced by the National Bureau of Standards, now NIST - National Institute of Standards and technology) subsequently replaced by NBS-OxII. These are both internationally calibrated and certified materials, whose "1"4C activities are known absolutely. A second tier of materials, often called secondary standards or reference materials, and including internationally recognised materials such as ANU-sucrose (now also IAEA-C6), Chinese - sucrose and the IAEA C1-C6 series, augmented by additional oxalic acid samples are also used routinely. The activity of these materials has been estimated from large numbers of measurements made by many laboratories. Recently, further natural materials from the Third and Fourth International Radiocarbon Inter-comparisons (TIRI and FIRI) ...
2004-08-01
Energy Technology Data Exchange (ETDEWEB)
Inverted growth and the development of associated cell processing, are likely to offer a significant degree of freedom for improving the performance of many III-V multijunction cascades and open new avenues for advanced multijunction concepts. This is especially true for the development of high-efficiency Al[sub 0.37]Ga[sub 0.63]As/GaAs cascades where the high growth temperatures required for the AlGaAs top cell growth can cause the deterioration of the tunnel junction interconnect. In the approach of inverted-grown AlGaAs/GaAs cascade cells, the AlGaAs top cell is grown first at 780 [degree]C and the GaAs tunnel junction and bottom cell are grown at 675 [degree]C. After the inverted growth, the AlGaAs/GaAs cascade structure is selectively removed from the parent substrate. The feasibility of inverted growth is demonstrated by a fully-processed, inverted-grown, thin film GaAs cell with a 1-sun AM1.5 efficiency of 20.3%. Also, an inverted-grown, thin-film, Al[sub ...
1992-12-01
International Nuclear Information System (INIS)
A series of separation experiment was performed in order to study a multi-functional spent fuel reprocessing process based on ion-exchange technique. The tertiary pyridine-type anion-exchange resin was used in this experiment and the mixed oxide fuel highly irradiated in the experimental fast reactor ''JOYO'' was used as a reference spent fuel. As the result, "1"0"6Ru + "1"2"5Sb, "1"3"7Cs + "1"5"5Eu + "1"4"4Ce, plutonium, americium and curium could be separated from the irradiated fuel by only three steps of ion-exchange. The decontamination factor of "1"3"7Cs and trivalent lanthanides ("1"5"5Eu, "1"4"4Ce) in the final americium product exceeded 3.9 x 10"4 and 1.0 x 10"5, respectively. The decontamination factor for the mutual separation of "2"4"3Cm and "2"4"1Am was larger than 2.2 x 10"3 for the americium product and, moreover, the content of "1"3"7Cs, trivalent lanthanides and "2"4"3Cm included in "2"4"1Am product did not exceed 2 ppm. These ...
2006-06-01
Energy Technology Data Exchange (ETDEWEB)
Investigation of an HP-blade damage in 1996 and an MP-blade damage in 1007 at the mounting showed that fretting and creep fatigue had caused the damage. Break-down occurred when creep-related cracks developed between radial bridge to the upper blade tooth and weight relief boreholes. After disassembly of the HP-blades the lower blade tooth was found to be cracked after fretting (some cracks along the whole length of the tooth). The lower teeth of MP-bladedes showed merely superficial cracks (depth about 0.4mm). The massive cracks of the lower blade tooth were caused by instationary clearance changes combined with hard blade underground.(orig.) [German] Das Ergebnis der Untersuchung nach einem HD-Schaufelschaden 1996 sowie einem MD-Schaufelschaden 1997 an der Vierzackenfussbefestigung ergab Zeitstanderschoepfung und Fretting als auszuloesende Schadensmechanismen. Die Havarien wurden durch zeitstandbedingte Brueche zwischen Radienuebergang zum oberen Schaufelzacken und ...
1998-07-01
Corrosion fatigue of magnesium alloys
Energy Technology Data Exchange (ETDEWEB)
To study the fatigue life of extruded AZ31 (3%Al, 1%Zn, 0.3%Mn, Mg - the rest), AM50 (5%Al, 0.4%Mn, Mg - the rest) and ZK60 (5%Zn, 0.5%Zr, Mg - the rest) Mg alloys in air and NaCl-based solutions, corrosion fatigue tests were carried out using a rotating beam type fatigue machine. For the analysis of the corrosion fatigue behavior of Mg alloys in different environments, fitted N{sub sol}/N{sub air} ratio considered as a relative corrosion fatigue life is used. Here N{sub sol} and N{sub air} are the numbers of cycles to failure in the solution and in air, respectively. An extruded ZK60 alloy shows very high fatigue and corrosion fatigue properties in comparison with other alloys. However, ZK60 shows the lowest values of the relative fatigue life (N{sub sol}/N{sub air} {proportional_to}10{sup -3}-10{sup -2}) compared to that for AM50 and AZ31 alloys (N{sub sol}/N{sub air} {proportional_to}10{sup -2} - 10{sup -1}). Generally, extruded alloys in ...
2003-07-01
Construction, testing of the 1 MW, 130-260 GHz Fusion-FEM
Energy Technology Data Exchange (ETDEWEB)
During the previous 9 months the major part of the Fusion-FEM has been constructed. The 2 MV Insulated Core Transformer, the electron gun, the accelerator, the focusing lenses and the undulator have been tested on-site. In the present - temporary - set-up, the electron beam line consists of a 12 A, 80 keV thermionic electron gun, a 2 MeV dc accelerator, beam transport optics, the undulator and a collector. The gun is mounted in the high voltage terminal, which is now at -2 MV, and the undulator and mm-wave system am at ground potential outside the SF{sub 6}-filled pressure tank. This so-called inverse set-up allows easy access to the larger part of the beam line, the undulator and the mm-wave system, which is important in the conditioning phase. The decelerator and depressed collector am not yet installed. The design of the electron beam line has been optimised using the GPS particle-tracking code and the TOSCA code. The TOSCA code is used for ...
1995-12-31
Analysis of a Fast Spectrum Irradiation Facility in the High Flux Isotope Reactor
Energy Technology Data Exchange (ETDEWEB)
The Global Nuclear Energy Partnership (GNEP) is proposing to develop a sodium-cooled fast-spectrum reactor (SFR) to transmute and consume actinides from discharged nuclear fuel. To meet performance objectives, new and advanced fuels and targets need to be developed. The fuels to be irradiated include metal and oxide mixed actinides (U-Np-Pu-Am-Cm); for the target concept, Am-Cm has been considered. A significant part of the development process is the irradiation of the fuel and cladding in a prototypic fast reactor environment to determine the performance under irradiation. Analysis results are presented in this paper for a fast-neutron irradiation facility design based on the large fast neutron flux available in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) combined with the use of a strongly-absorbing thermal neutron shield. Several designs were assessed; the preferred concept consists of a three-pin design with ...
2008-09-01
Plutonium isotopes (239Pu and 238Pu, and 241Am) with a total activity of 269 kBq were accidentally deposited in a puncture wound of the right index finger of a nuclear worker at the Mayak Production Association. Tissues surrounding the wound site contaminated with radionuclides were excised 4.5 h after the injury. Residual contamination within the wound amounted to 0.05% of the initial contamination. The 10-d therapy with CaNa3-diethylene triamine pentaacetate acid (CaNa3-DTPA) was performed in parallel with in vivo measurements of the wound site and daily urine bioassays. The wound intake of radionuclides was consistent with two forms of radioactive materials detected within the wound site, i.e., soluble compounds and a large fragment, which was completely removed by excision. On day 9 after the injury, the clearance rate from the wound site was 1.8 times higher than the rate predicted by the National Council on Radiation Protection and Measurements (NCRP) model ...
2010-10-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: To report on the nephron-sparing, percutaneous ablation of a large renal cell carcinoma by combined superselective embolization and percutaneous radiofrequency ablation. Materials and Methods: A 5 cm renal cell carcinoma of a 43-year-old drug abusing male with serologically proven HIV, hepatitis B and C infection, who refused surgery, was superselectively embolized using microspheres (size: 500 - 700 {mu}m) and a platinum coil under local anesthesia. Percutaneous radiofrequency ablation using a 7F LeVeen probe (size of expanded probe tip: 40 mm) and a 200 Watt generator was performed one day after transcatheter embolization under general anesthesia. Results: The combined treatment resulted in complete destruction of the tumor without relevant damage of the surrounding healthy renal tissue. The patient was discharged 24 hours after RF ablation. No complications like urinary leaks or fistulas were observed and follow up CT one day and 4 weeks after the radiofrequency ...
2001-11-01
Energy Technology Data Exchange (ETDEWEB)
The U.S. Department of Energy (DOE) has been developing a nuclear waste disposal facility, the Waste Isolation Pilot Plant (WIPP), located approximately 42 km east of Carlsbad, New Mexico. The WIPP is designed to demonstrate the safe disposal of transuranic wastes produced by the defense nuclear-weapons program. Pefiormance assessment analyses (U.S. DOE, 1996) indicate that human intrusion by inadvertent and intermittent drilling for resources provide the only credible mechanisms for significant releases of radionuclides horn the disposal system. These releases may occur by five mechanisms: (1) cuttings, (2) cavings, (3) spallings, (4) direct brine releases, and (5) long- term brine releases. The first four mechanisms could result in immediate release of contaminant to the accessible environment. For the last mechanisq migration pathways through the permeable layers of rock above the Salado are important, and major emphasis is placed on the Culebra Member of the Rustler Formation ...
1998-09-01
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, ...
Wear properties of steel plasma nitrided at high temperatures
Energy Technology Data Exchange (ETDEWEB)
The wear behaviour of 722M24 (En40B) steel plasma nitrided at high temperatures for long durations was investigated. Under dry sliding and abrasive-containing lubricated conditions, the wear characteristics of the steel were studied as a function of load, time and white layer thickness. The white layer and the wear debris were characterized by X-ray diffraction. The topography of the wear surface was examined in a scanning electron microscope. The plasma nitriding process was carried out using a 20 kW plasma processing unit in cracked ammonia atmosphere. Treatment times of up to 100 h were employed with temperatures of 550, 570 and 590 C. Wear tests were performed with plasma nitrided AMS 6472 as the counterface material. The tests under abrasive-containing lubricated conditions were carried out with 10% carborundum powder 10 [mu]m in size in SAE-30 machine oil. The wear resistance of the steel was improved by plasma nitriding and the abrasive wear resistance of ...
1993-08-30
WLUP3.0, 69 and 172 Group Cross Section Libraries for WIMS
International Nuclear Information System (INIS)
Description or function: WLUP contains validated WIMS-D formatted cross section libraries in 69 and 172 energy group structures for nuclear reactor calculations. Materials from recently released evaluated nuclear data libraries are included. The NJOY nuclear data processing system was applied for generating the cross section files following the models and conventions built into the WIMS-D lattice code. The relevant features for the WIMS users are: - Energy group structures: 69 and 172 energy groups. - List of materials: WIMS ID, general information, source of data. - Cross sections: 69 and 172 group plots. - Resonance data: WIMS ID, temperature, background cross sections. - Goldstein-Cohen factors: Goldstein-Cohen lambda values. - Thermal scattering data: thermal scattering laws and P1 matrixes. - Fission spectrum: fission spectrum data. - Burnup data: burnup chains. - Fission product yields: fission yield tables. - Pseudo lumped fission product: Description of pseudo fission product. ...
Energy Technology Data Exchange (ETDEWEB)
The authors investigated the development of tribochemical reaction layers and surface-level structural changes in a fuel-lubricated roller bearing steel 100Cr6 in the limiting friction range, using two different variants of surface treatment and heat treatment. Tribological experiments were carried out in a laboratory test stand with reversing sliding wear under varying loads and with a varying number of friction cycles. [German] Ziel der vorliegenden Arbeit war es, die Entstehung von tribochemischen Reaktionsschichten und oberflaechennahen Gefuegeaenderungen am Waelzlagerstahl 100Cr6 bei Kraftstoffschmierung im Grenzreibungsbereich fuer je zwei Oberflaechenbearbeitungen und Waermebehandlungen zu untersuchen. Dazu wurden tribologische Kurzversuche in einem Laborpruefstand mit reversierender Gleitbeanspruchung unter Variation der Last und der Anzahl der Reibzyklen durchgefuehrt. (orig.)
2000-08-01
Treatment of low-frequency pulsating magnetic field on amorphous alloy Fe_7_8Si_9B_1_3
International Nuclear Information System (INIS)
Effect of low-frequency pulsating magnetic field on the microstructure and magnetic properties of amorphous alloy Fe_7_8Si_9B_1_3 were investigated. The temperature rise induced by the treatment was measured by a non-contact infrared thermometer. The crystallization behavior and microstructure of specimens were studied by Moessbauer spectroscopy and transmission electron microscope (TEM). Magnetic properties of the specimens were investigated by alternating gradient magnetometer (AGM). The results show that the low-frequency pulsating magnetic field can promote the single-phase crystallization of amorphous alloy Fe_7_8Si_9B_1_3. The frequency, f of applied field is from 10 to 40 Hz, magnetic field, H is from 0.02 to 0.04 T and treatment duration, t is from 180-300 s. The volume fraction of crystallization phase (#alpha#-Fe(Si), the grain size, 2-10 nm) is 3-7%. The temperature rise less than 7 deg. C. Magnetic properties of samples are improved by magnetic field. The field's f is 40 ...
2007-07-15
Energy Technology Data Exchange (ETDEWEB)
An ASTER (advanced spaceborne thermal emission and reflection radiometer) is one of the image sensors. It is to be installed in an earth survey polar orbit platform satellite, EOS-AM1, which is to be launched in 1998, and it is going to start its operation. Data observed by the thermal infrared remote sensing of ASTER include the spectral emissivity, and the spectral emission reflectivity which is expressed by the function of temperature. It is required to overcome technical problems how to extract the spectral emissivity from the observed data. The spectral emissivity extracted from the remote sensing data by the MMD method, measured for samples collected in Cuprite area, Nevada, and/or measured at sampled points were compared to each other and discussed. The hemisphere spectral reflectivity, which is indirect spectral emissivity, agreed well with the direct spectral emissivity. Data suggesting the establishment of Kirchhoff`s law were obtained even for the ...
1996-10-01
Energy Technology Data Exchange (ETDEWEB)
This paper deals with the externally coal-fired combined cycle (EFCC). A process simulation for different configurations of the EFCC-process is carried out as well as an investigation of the effect of the key parameters such as the gas turbine inlet temperature and the compressor intake airflow. The results show a promising potential of the efficiency. One component of this combined gas and steam turbine cycle is a high temperature heat exchanger that has to withstand the extrem chemical and thermal operating conditions. Fibre reinforced ceramics and combinations of them with monolithic ceramics seem to be the most promising materials for this application. A cost estimating of the EFCC-process shows that a competitive operation should be possible. (orig.) [Deutsch] Die Ergebnisse der Prozesssimulationen weisen ein vielversprechendes Wirkungsgradpotential des extern kohlebefeuerten Gasturbinenprozesses auf. Der fuer dieses neue Kraftwerkskonzept notwendige Hochtemperatur-Waermetauscher ...
1996-12-31
Test plan for single well injection/extraction characterization of DNAPL
Energy Technology Data Exchange (ETDEWEB)
Soils and groundwater beneath an abandoned Process sewer line in the A/M Area of the Savannah River Site (SRS) contain elevated levels of volatile organic compounds, specifically trichloroethylene (TCE) and tetrachloroethylene (PCE), two common chlorinated solvents. These compounds have low aqueous solubilities, thus when released to the subsurface in sufficient quantity, tend to exist as immiscible fluids or nonaqueous phase liquids (NAPLs). Because chlorinated solvents are also denser than water, they are referred to by the acronym DNAPLS, or dense non aqueous Phase liquids. Technologies targeted at the efficient characterization or removal of DNAPL are not currently proven. For example, most DNAPL studies rely on traditional soil and water sampling and the fortuitous observation of immiscible solvent. Once DNAPL is identified, soil excavation (which is only applicable to small contained spill sites) is the only ``proven`` cleanup method. New cleanup approaches ...
1995-12-01
Energy Technology Data Exchange (ETDEWEB)
Soils and groundwater beneath an abandoned process sewer line in the A/M Area of the Savannah River Site (SRS) contain elevated levels of volatile organic compounds, specifically trichloroethylene (TCE) and tetrachloroethylene (PCE), two common chlorinated solvents. These compounds have low aqueous solubilities, thus when released to the subsurface in sufficient quantity, tend to exist as immiscible fluids or nonaqueous phase liquids (NAPLs). Because chlorinated solvents are also denser than water, they are referred to by the acronym DNAPLs, or dense non-aqueous phase liquids. Technologies targeted at the efficient characterization or removal of DNAPL are not currently proven. For example, most DNAPL studies rely on traditional soil and water sampling and the fortuitous observation of immiscible solvent. Once DNAPL is identified, soil excavation (which is only applicable to small contained spill sites) is the only proven cleanup method. New cleanup approaches based ...
1996-09-01
Reversal in time order of interactive events: Collision of inclined rods
In the rod and hole paradox as described by Rindler (1961 Am. J. Phys. 29 365-6), a rigid rod moves at high speed over a table towards a hole of the same size. Observations from the inertial frames of the rod and slot are widely different. Rindler explains these differences by the concept of differing perceptions in rigidity. Gron and Johannesen (1993 Eur. J. Phys. 14 97-100) confirmed this aspect by computer simulation where the shapes of the rods are different as observed from the co-moving frames of the rod and slot. Lintel and Gruber (2005 Eur. J. Phys. 26 19-23) presented an approach based on retardation due to speed of stress propagation. In this paper we consider the situation when two parallel rods collide while approaching each other along a line at an inclination with their axis. The collisions of the top and bottom ends are reversed in time order as observed from the two co-moving frames. This result is explained by the concept of extended present ...
2008-01-01
Energy Technology Data Exchange (ETDEWEB)
The document describes the outcome of the CSN/CIEMAT-00 interlaboratory test comparison among environmental radioactivity laboratories. the exercise was organised according to the ISO-43 and the ISO/IUPAC/AOAC Harmonized Protocol for the proficiency testing of analytical laboratories. the test sample was a soil containing environmental levels of K-40, Ra-226, Ac-228, Sr-90, Cs-137, Cs-134, Pu (239-240) y Am-241. the Universidad Autonoma de Barcelona prepared the material and reported adequate statistical studies of homogeneity. The results of the exercise were computed for 30 participating laboratories, and their analytical performance was assessed using the u-score approach. A raised percentage of satisfactory laboratory performance has been obtained for all the analysis, being the best performance in gamma measurements. The exercise has drawn that several laboratories have difficulties in the evaluation of combined uncertainty, mainly in analysis involving ...
2002-07-01
Radioanalytical methods of rare earth element determination
International Nuclear Information System (INIS)
Instrumental neutron activation analysis (INAA) and radionuclide X-ray fluorescence analysis (RXFA) were used for the determination of rare earth elements. For INAA, solution obtained by sample decomposition was dripped onto filter paper, enclosed and sealed into a polyethylene foil. The sample was activated in reactor WWR-S over a period of 4 to 6 hours with a neutron fluence of 10"1"3cm"-"2. Gamma radiation measurement was carried out with a planar and a coaxial HP-Ge detector in three decay periods. La, Ce, Nd, Sm, Eu, Gd, Tb, Ho, Tm, Yb and Lu were determined. The advantage of the method is its accuracy and high sensitivity, the disadvantage is the time-consuming analysis. The RXFA method was used as a rapid and operative method for the analysis of loose ore samples, aqueous and organic solutions of rare earth elements. For exciting X-ray radiation, "2"4"1Am was used and the radiation of K-lines was detected with a planar Si(Li) detector. For elements beyond Dy ...
1989-06-01
Radioanalytical determination of chromium in welding fumes
International Nuclear Information System (INIS)
Radionuclide X-ray fluorescence analysis and fast neutron activation analysis were used for the determination of chromium. The excitation source for X-ray fluorescence analysis was a ring-shaped "2"4"1Am source with an activity of 18.5x10"9 Bq. SYNPOR filters of 35 mm in diameter were used for the measurement. The 5.414 keV Cr peak was measured with a Si(Li) detector. The sensitivity was 0.05 mg for a period of measurement of 1000 s. A neutron generator with an emission of 10"9 s"-"1 was used as the source of fast neutrons. "5"2V and "5"3V, the products of nuclear reaction with Cr, were measured gamma spectrometrically with a Ge(Li) detector. The sensitivity for Cr is 0.015 mg, in the presence of Mn which causes interference the sensitivity is a mere 0.075 mg. The mentioned methods were used to determine total Cr and Cr(VI) in welding aerosols. It was found that the most toxic form, i.e., Cr(VI), is released during manual arc welding of high alloy steels with ...
1985-01-01
Pneumokokkenkonjugatimpfstoffe ? Expertenkonsens
British Library Electronic Table of Contents (United Kingdom)
Zusammenfassung Seit Dezember 2009 ist in Deutschland neben einem 10-valenten (PCV10) auch ein 13-valenter Pneumokokkenkonjugatimpfstoff (PCV13) verf?gbar. Ein Wechsel von PCV7 zu PCV13 ist zu jedem Zeitpunkt einer begonnenen Impfserie problemlos m?glich, von PCV7 zu PCV10 nur bei der Boosterimpfung. F?r alle Kinder mit abgeschlossener vollst?ndiger PCV7- oder -10-Impfserie stellt sich die Frage, ob eine zus?tzliche Impfung mit PCV13 sinnvoll ist. Kinder mit erh?htem Risiko f?r Pneumokokkenerkrankungen gem?? STIKO (St?ndige Impfkommission am Robert?Koch-Institut), die mit PCV7, jedoch nicht mit PPV23 geimpft sind, sollten grunds?tzlich mit PCV13 geimpft werden. Zu diesen Risikokindern sind evtl. auch gesunde, aber bereits im fr?hen Alter in Gemeinschaftseinrichtungen betreute Kinder zu rec...
2011-01-01
Plutonium Finishing Plant safety evaluation report
Energy Technology Data Exchange (ETDEWEB)
The Plutonium Finishing Plant (PFP) previously known as the Plutonium Process and Storage Facility, or Z-Plant, was built and put into operation in 1949. Since 1949 PFP has been used for various processing missions, including plutonium purification, oxide production, metal production, parts fabrication, plutonium recovery, and the recovery of americium (Am-241). The PFP has also been used for receipt and large scale storage of plutonium scrap and product materials. The PFP Final Safety Analysis Report (FSAR) was prepared by WHC to document the hazards associated with the facility, present safety analyses of potential accident scenarios, and demonstrate the adequacy of safety class structures, systems, and components (SSCs) and operational safety requirements (OSRs) necessary to eliminate, control, or mitigate the identified hazards. Documented in this Safety Evaluation Report (SER) is DOE`s independent review and evaluation of the PFP FSAR and the basis for ...
1995-01-01
Non-Detection of Polarized, Scattered Light from the HD 189733b Hot Jupiter
Using the POLISH instrument, I am unable to reproduce the large-amplitude polarimetric observations of Berdyugina et al. (2008) to the >99.99% confidence level. I observe no significant polarimetric variability in the HD 189733 system, and the upper limit to variability from the exoplanet is Delta_P < 7.9 x 10^(-5) with 99% confidence in the 400 nm to 675 nm wavelength range. Berdyugina et al. (2008) report polarized, scattered light from the atmosphere of the HD 189733b hot Jupiter with an amplitude of two parts in 10^4. Such a large amplitude is over an order of magnitude larger than expected given a geometric albedo similar to other hot Jupiters. However, my non-detection of polarimetric variability phase-locked to the orbital period of the exoplanet, and the lack of any significant variability, shows that the polarimetric modulation reported by Berdyugina et al. (2008) cannot be due to the exoplanet.
2009-01-01
The main LHC superconducting magnets (dipoles and quadrupoles) use Rutherford type cables, stabilized electrically and thermally with copper profiles. The portions of cables are connected to each other by a soft soldering technique (Sn96Ag4) with an overlapping length corresponding to one pitch of the superconducting strands. The splice constitutes a "composite" structure with the interchanging layers of Sn96Ag4 and NbTi superconductor, located inside a Cu cage. In order to ensure a high level of reliability (failure probability not exceeding 10-8) for some 10000 connections in the LHC, a non-destructive technique to check the quantity of solder in the joint is foreseen. The technique is based on a gamma ray source (241Am) and the detection is position-sensitive in the transmission mode. Scintillating detectors of gamma rays are used and their accumulated length corresponds to the length of the radioactive source (120 mm). The method can be used in-situ, the ...
2004-01-01
British Library Electronic Table of Contents (United Kingdom)
The effect of Mo addition on the glass-forming ability (GFA), magnetic properties, mechanical properties and corrosion resistance of (Fe0.76Si0.096B0.084P0.06)100-xMox (x=0, 2, 4 and 6at.%) bulk glassy alloys (BGAs) with high Fe contents was investigated. The 2at.% Mo addition makes the alloy composition approach towards a eutectic point, which could result in an increase in the GFA. The BGA rod with diameters up to 3.5mm was produced by copper mold casting. These BGAs exhibit a rather high saturation magnetization of 0.98-1.51T and lower coercive force of 1.7-2.1A/m. A significant improvement in corrosion resistance was observed with microalloying Mo element in 1N H2SO4 solution. Furthermore, these Fe-based BGAs show super-high strength of ~3.3GPa and Young's modulus of 200GPa.
2011-01-01
International Nuclear Information System (INIS)
The Rocky Flats Environmental Technology Site (RFETS) has historically released radionuclide chemicals of potential concern into the surrounding environment. The off-site environment was evaluated for Pu"2"3"9"/"2"4"0 and Am"2"4"1 occurrence. An evaluation of exposure and effects to the aquatic ecology within off-site areas including: Standley Lake, Great Western Reservoir, Mower Reservoir and portions of Big Dry Creek, Walnut Creek, and Woman Creek was performed for the completion of an Ecological Risk Assessment. Collocated sampling activities were performed for surface water, sediment, benthic macroinvertebrates and fish. Results of the analytical data were used to assess ongoing exposure and effects. Data collected to determine effects (chemical content of fish tissue, diversity and density of macroinvertebrate populations) provided some of the necessary information needed to evaluate risk. However, due to conditions of interfering stressor effects, a ...
1995-11-05
Measuring instrument for radiometric monitoring of solids and heavy metals in water
International Nuclear Information System (INIS)
A combination of measuring instruments, consisting of a Beta-Sedimeter and a radionuclide X-ray fluorescence instrument, is described. With the Beta-Sedimeter the C-14-radiation is measured. Through direct irradiation with photons of a Pu238-source in an ancillary irradiation chamber and energy dispersing measurement of the K- and L-radiation resp. of the excited heavy metals with the aid of a Si(Li)-semiconductor detector and a 4-channel analyzer the heavy metal concentrations of the heavy metals Zn, Cr, Ni and Pb are determined. For the determination of cadmium the indirect excitation with Am-241 and Dy-targets is described. The system produces records and operates fully automatically in a step-by-step mode with a testing cycle of 45 minutes. In connection with the process monitoring of the wastewater from a zinc plating plant during a period of 8 months the concentration of the solid material and of the metals Cr and Zn, which were considered to be ...
1979-01-01
Measurement of relative L X-ray intensity ratio following radioactive decay and photoionization
International Nuclear Information System (INIS)
The measurements of the L X-ray intensity ratio I(L?)/I(L?), I(L?)/I(L?), I(L?)/I(L?), I(L?)/I(L?) and I(L?)/I(L?) for elements Dy, Ho, Yb, W, Hg, Tl and Pb were experimentally determined both by photon excitation, in which 59.5 keV ?-rays from a filtered radioisotope 241Am was used, and by the radioactive decay of 160Tb, 160Er, 173Lu, 182Re, 201Tl, 203Pb and 207Bi. L X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the calculated theoretical values. Theoretical values of the I(L?/L?), I(L?/L?), I(L?/L?), I(L?/L?) and I(L?/L?) intensity ratios were calculated using theoretically tabulated values of subshell photoionization cross-section, fluorescence yield, fractional X-ray emission rates, Coster-Kronig transition probabilities. It was observed that present values agree with previous theoretical and other available experimental results.
2008-05-22
Measurement of relative K X-ray intensity ratio following radioactive decay and photoionization
Energy Technology Data Exchange (ETDEWEB)
The measurements of the K X-ray intensity ratio I(K{alpha} {sub 2}/K{alpha} {sub 1}), I(K{beta} {sub 1}/K{alpha} {sub 1}) and I(K{beta}/K{alpha}) for elements V, Mn, Zn, Tc, Ru, Cd, Xe, Ba, Cs, Hg and Rn were experimentally determined both by photon excitation, in which 59.5 keV {gamma}-rays from a {sup 241}Am and 123.6 keV {gamma}-rays from a {sup 60}Co were used, and following the radioactive decay of {sup 51}Cr, {sup 55}Fe, {sup 67}Ga, {sup 99}Tc, {sup 111}In, {sup 131}I, {sup 133}Ba, {sup 133}Xe, {sup 137}Cs, {sup 201}Tl and {sup 226}Ra. K X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the theoretical values. It was observed that present values agree with the previous theoretical and other experimental results.
2007-01-15
Measurement of relative K X-ray intensity ratio following radioactive decay and photoionization
International Nuclear Information System (INIS)
The measurements of the K X-ray intensity ratio I(K#alpha# _2/K#alpha# _1), I(K#beta# _1/K#alpha# _1) and I(K#beta#/K#alpha#) for elements V, Mn, Zn, Tc, Ru, Cd, Xe, Ba, Cs, Hg and Rn were experimentally determined both by photon excitation, in which 59.5 keV #gamma#-rays from a "2"4"1Am and 123.6 keV #gamma#-rays from a "6"0Co were used, and following the radioactive decay of "5"1Cr, "5"5Fe, "6"7Ga, "9"9Tc, "1"1"1In, "1"3"1I, "1"3"3Ba, "1"3"3Xe, "1"3"7Cs, "2"0"1Tl and "2"2"6Ra. K X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the theoretical values. It was observed that present values agree with the previous theoretical and other experimental results.
2007-01-01
Long-lived radionuclides in the coastal sediments of the Irish Sea, UK
Energy Technology Data Exchange (ETDEWEB)
Over the last four decades the Irish Sea has received controlled discharges of radioactive effluents from the Sellafield (Windscale) nuclear fuel reprocessing plant in Cumbria, UK. Enhanced levels of a range of fission, activation and transuranic elements have been reported in a variety of environmental media. Most of the {sup 239,240}Pu and {sup 241}Am and about 10% of the {sup 137}Cs have been retained in a deposit of the fine sediment near the discharge point. The quantities of radionuclides discharged annually from Sellafield decreased by two orders of magnitude from the mid-1970s to 1990, but estimated critical group internal and external exposure decreased by less than one order of magnitude over this period. Redistribution of the contaminated marine sediment is potentially of major significance. In this paper, a review is presented of published work and recent our study relating to Sellafield waste long-lived radionuclides, especially transuranium elements, ...
1996-12-01
Energy Technology Data Exchange (ETDEWEB)
K{beta}-to-K{alpha} X-ray intensity ratios of Ti, V, Cr, and Co in pure metals and their disilicide compounds have been measured following excitation by 59.54 keV {gamma}-rays from a 200 mCi {sup 241}Am point-source. The K{beta}-to-K{alpha} intensity ratios of all these metals in the disilicide compounds are found to be less than the corresponding ratios for pure metals. Comparison of the measured K{beta}-to-K{alpha} intensity ratios for the disilicides and pure metals with the multiconfiguration Dirac-Fock calculations indicates increase of the 3d electron populations of Ti, V, Cr, and Co in the disilicides from their pure metal values suggesting the rearrangement of electrons between 3d and 4s states of the individual metal atom. This rearrangement is found to be opposite to that observed in our previously reported work on NiSi{sub 2} and CuSi{sub 2}.
1999-06-01
Korrelation von Tonschwellenaudiogramm und H?rverlust f?r Zahlen
British Library Electronic Table of Contents (United Kingdom)
Zusammenfassung Hintergrund Die vorliegende Arbeit untersucht, welche Frequenzkombination f?r die Berechnung der mittleren H?rverluste im Tonschwellenaudiogramm am besten mit dem H?rverlust f?r Zahlen im Sprachaudiogramm korreliert, da in der Literatur verschiedene Rechenvarianten f?r diese gutachterliche Plausibilit?tspr?fung beschrieben werden. Es wurden die 3?Rechenvarianten A (250, 500 und 1000?Hz), B (500 und 1000?Hz) und C (500, 1000 und 2000?Hz) verglichen. Methoden Die Audiogramme von 80?Normalh?rigen, 106?Schwerh?rigen und 135 zu Begutachtenden wurden retrospektiv analysiert. Die Differenzen der Mittelwerte aus dem Tonschwellenaudiogramm und dem H?rverlust f?r Zahlen wurden f?r das rechte und linke Ohr getrennt in den 3?Patientenkollektiven berechnet und statistisch verglichen. Er...
2011-01-01
International Nuclear Information System (INIS)
K#beta#-to-K#alpha# X-ray intensity ratios of Ti, V, Cr, and Co in pure metals and their disilicide compounds have been measured following excitation by 59.54 keV #gamma#-rays from a 200 mCi "2"4"1Am point-source. The K#beta#-to-K#alpha# intensity ratios of all these metals in the disilicide compounds are found to be less than the corresponding ratios for pure metals. Comparison of the measured K#beta#-to-K#alpha# intensity ratios for the disilicides and pure metals with the multiconfiguration Dirac-Fock calculations indicates increase of the 3d electron populations of Ti, V, Cr, and Co in the disilicides from their pure metal values suggesting the rearrangement of electrons between 3d and 4s states of the individual metal atom. This rearrangement is found to be opposite to that observed in our previously reported work on NiSi_2 and CuSi_2.
1999-06-01
High-efficiency solar cell and method for fabrication
A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD). ...
1999-08-31
High-efficiency GaAs solar cells on mm and sub-mm grain-size polycrystalline Ge substrates
Energy Technology Data Exchange (ETDEWEB)
GaAs material and device structure optimization studies on optical-grade, millimeter-and-less grain-size polycrystalline Ge substrates are presented. We discuss the growth of high-quality epitaxial layers across various crystalline orientations of a polycrystalline substrate; this is important for obtaining high-performance solar cells. The GaAs solar cell on n-type poly-Ge substrate is a p-on-n type, with an undoped spacer between the p-emitter and the n-base. An experimental study of dark currents in these junctions, with and without the spacer, as a function of temperature (77K to 288K) is presented; this study suggests that the spacer reduces the tunneling contribution to dark current. In addition, we describe device-structure optimization studies that have led us to achieve an open-circuit voltage (V{sub oc}) exceeding 1 Volt and an AM1.5 efficiency of {approximately}19{percent} for a 4-cm{sup 2}-area GaAs cell on sub-mm grain-size poly-Ge. We have also ...
1997-02-01
Heavy-ion linear induction accelerators as drivers for inertial fusion power plants
International Nuclear Information System (INIS)
A linear induction accelerator that produces a beam of energetic heavy ions (T #approx =# 10 GeV, A #approx =# 200 am#mu#) is a prime candidate as a driver for an inertial fusion power plant. Some early perceptions were that heavy-ion driven fusion would not be cost-competitive with other power sources because of the high cost of the accelerators. However, improved understanding of the physics of heavy-ion transport and acceleration (supported by experimental results), combined with advances in accelerator technology, have resulted in accelerator design costs -- 50% of previous estimates. As a result, heavy-ion driven fusion power plants conceptual fusion power plants. A brief formulation of transport and acceleration physics is presented here, along with a description of the induction Linac cost optimization code LIACEP. Cost trends are presented and discussed, along with specific cost estimates for several accelerator designs matched to specific inertial fusion ...
Energy Technology Data Exchange (ETDEWEB)
The adaption of the Muster-VAwS (model ordinance on the handling of water endangering substances in plants and specialized facilities) in the ordinances of the different German states, means that the legislator has laid down concrete - technical and organizational - requirements concerning the handling of water-endangering substances for all plants. The present example of the systematic stocktaking of all environmentally relevant substances in the context of the operation of the pumped storage plants of Schluchseewerk AG, Freiburg, an the application of the model operating instructions for hydropower plants shall serve to illustrate two important aspects for the implementation of this extensive ordinance. (orig.) [Deutsch] Durch Umsetzung der Muster-VAwS (Muster-Verordnung ueber Anlagen zum Umgang mit wassergefaehrdenden Stoffen und Fachbetriebe) in entsprechende Laenderverordnungen wurden durch den Gesetzgeber konkrete Anforderungen, technisch und organisatorisch, fuer alle Anlagen ...
1998-08-01
Anti-proton and positron Galactic cosmic ray (GCR) spectra are among the key targets for indirect detection of dark matter (DM). The boost factors, corresponding to an enhancement of the signal|linked to the clumpiness properties of the dark matter distribution|, have been taken as high as thousands in the past. The dramatic impact of these boost factors for indirect detection of antiparticles, for instance with the PAMELA satellite or the coming AMS-02 experiment, asks for their detailed calculation. We take into account the state-of-the-art results of high resolution N-body dark matter simulations to calculate the most likely energy dependent boost factors|linked to the GCR propagation properties|, for anti-protons and positrons. The results from extreme, but still possible, configurations of the clumpy dark matter component is also discussed. Starting from the mass and space distributions of sub-halos, the anti-proton and positron propagators are used to ...
2007-01-01
Energy Technology Data Exchange (ETDEWEB)
In this work, a new class of thiadiazole derivatives, namely 3,5-bis(2-thienyl)-1,3,4-thiadiazole (2-TTH) and 3,5-bis(3-thienyl)-1,3,4-thiadiazole (3-TTH), have been studied as possible corrosion inhibitors for mild steel in molar hydrochloric acid (1M HCl). Polarisation curves and AC impedance methods have been used. These studies have shown that the thiadiazole derivatives were very good inhibitors for mild steel in 1M HCl. Comparison of results showed that 3-TTH was the best inhibitor. The potential of zero charge (PZC) of mild steel was studied by ac impedance method, and the mechanism of adsorption has been predicted. X-ray photoelectron spectroscopy surface analysis with thiadiazole derivatives shows that it chemisorbed at the mild steel/HCl interface. The adsorption of these inhibitors followed Langmuir's adsorption isotherm. The electronic properties of 2-TTH and 3-TTH, obtained using the AM1 semi-empirical quantum chemical approach, were ...
2004-07-01
Development of a Novel Bioelectrochemical Membrane Reactor for Wastewater Treatment.
A novel bioelectrochemical membrane reactor (BEMR), which takes advantage of a membrane bioreactor (MBR) and microbial fuel cells (MFC), is developed for wastewater treatment and energy recovery. In this system, stainless steel mesh with biofilm formed on it serves as both the cathode and the filtration material. Oxygen reduction reactions are effectively catalyzed by the microorganisms attached on the mesh. The effluent turbidity from the BEMR system was low during most of the operation period, and the chemical oxygen demand and NH(4)(+)-N removal efficiencies averaged 92.4% and 95.6%, respectively. With an increase in hydraulic retention time and a decrease in loading rate, the system performance was enhanced. In this BEMR process, a maximum power density of 4.35 W/m(3) and a current density of 18.32 A/m(3) were obtained at a hydraulic retention time of 150 min and external resister of 100 ?. The Coulombic efficiency was 8.2%. Though the power density and current ...
2011-10-01
Development of GaInAsP for GaInAsP/Ge cascade solar cells
Energy Technology Data Exchange (ETDEWEB)
Quaternary semiconductor compounds are ideal candidates for use in monolithic cascade solar cells because the lattice constant and the bandgap of such compounds can be independently varied. The quaternary semiconductor compound Ga[sub 0.83]In[sub 0.17]As[sub 0.67]P[sub 0.33] not only is lattice matched to GaAs and Ge but also provides a current matched top cell for the GaInAsP/Ge monolithic cascade solar cell. Under concentration of 100 suns, the projected efficiency for such a cell is about 34%. The growth of Ga[sub 0.83]In[sub 0.17]As[sub 0.67]P[sub 0.33] lattice matched to GaAs and Ge has been demonstrated. GaInAsP solar cells have been grown on both GaAs and Ge substrates. A GaInAsP on GaAs solar cell with an active area efficiency of 23.2% for 1 sun, AM 1.5 direct illumination has been prepared. A proposed structure for the GaInAsP/Ge cascade cell is also given.
1992-12-01
Determination of small amounts of elements by radionuclide X-ray fluorescence analysis
International Nuclear Information System (INIS)
The determination of small amounts of elements by radionuclide X-ray fluorescence analysis is described. Samples containing 5x10"-"4 to 5x10"-"6 g of elements were fixed on a suitable carrier. For a coaxial configuration a low-energy source of the #gamma#/X type was used, namely an annular "2"4"1Am/Ag source with an activity of 7.4x10"8 s"-"1 (20 mCi), and for a configuration with side reflection source of the #beta#/X type was used, namely "1"4"7Pm/Sm with the activity of Pm(OH)_3 approximately 3.7x1O"1"0 s"-"1 (1 Ci). Cs, Ba, La, Pr, Nd, and Ag were determined by means of the Ksub(#alpha#) line and Hg, W, Er, and Pr by means of the Lsub(#alpha#) line. For all elements studied a detection limit of the order of 10"-"7 g was achieved. (author).
1975-01-01
Energy Technology Data Exchange (ETDEWEB)
An innovative horizontal drilling system was used to install two horizontal wells as part of an integrated demonstration project at the Savannah River Site (SRS), Aiken, South Carolina. The SRS is located in south-central South Carolina in the upper Coastal Plain physiographic province. The demonstration site is located near the A/M Area, and is currently known as the Integated Demonstration Site. The Department of Energy's Office of Technology Development initiated an integrated demonstration of innovative technologies for cleanup of volatile organic compounds (VOCS) in soils and groundwater at the SRS in 1989. The overall goal of the program is to demonstrate, at a single location, multiple technologies in the fields of drilling, characterization, monitoring, and remediation. Innovative technologies are compared to one another and to baseline technologies in terms of technical performance and cost effectiveness. Transfer of successfully demonstrated ...
1992-12-01
Energy Technology Data Exchange (ETDEWEB)
An innovative horizontal drilling system was used to install two horizontal wells as part of an integrated demonstration project at the Savannah River Site (SRS), Aiken, South Carolina. The SRS is located in south-central South Carolina in the upper Coastal Plain physiographic province. The demonstration site is located near the A/M Area, and is currently known as the Integated Demonstration Site. The Department of Energy`s Office of Technology Development initiated an integrated demonstration of innovative technologies for cleanup of volatile organic compounds (VOCS) in soils and groundwater at the SRS in 1989. The overall goal of the program is to demonstrate, at a single location, multiple technologies in the fields of drilling, characterization, monitoring, and remediation. Innovative technologies are compared to one another and to baseline technologies in terms of technical performance and cost effectiveness. Transfer of successfully demonstrated technologies ...
1992-12-01
Comparison of fault management applications in French and Finnish distribution control centers
Energy Technology Data Exchange (ETDEWEB)
This paper compares two systems providing advanced functions for real-time management of power distribution networks developed in Finland and in France. The overall aim of these systems is to minimize the operational costs (e.g. power losses, outage level, thermal limits). These are to be integrated with a Supervision Control and Data Acquisition system (SCADA) and heterogeneous databases such as network and geographical information systems (AM/FM/GIS). The Finnish system called OPERA has been developed in the past years at the Tampere University of Technology. It is now commercialised by the Versoft Ltd software company and used in 11 control centers. The French system, called AUSTRAL is in the industrialization phase by now at the Research and Development Division of EDF. It will be put into real operation in three distribution utilities in 1997. In this paper, we briefly introduce both systems and discuss their similarities and differences in more detail. The ...
1997-12-31
Chiral auxiliaries are promising emerging tools for the asymmetric synthesis of octahedral metal complexes. We recently introduced chiral salicyloxazolines as coordinating bidentate chiral ligands which provide excellent control over the metal-centered configuration in the course of ligand substitution reactions and can be removed afterward in an acid-induced fashion under complete retention of configuration (J. Am. Chem. Soc. 2009, 131, 9602-9603). Here reported is our detailed investigation of this sequence of reactions, affording virtually enantiopure ruthenium polypyridyl complexes. The control of the metal-centered chirality by the coordinated chiral salicyloxazolinate ligand was evaluated as a function of reaction conditions, the employed bidentate 2,2'-bipyridine and 1,10-phenanthroline ligands, and the substituent at the asymmetric 5-position of the oxazoline heterocycle. Most striking was the strong influence of the reaction solvent, with aprotic solvents ...
2010-09-01
CTH-process for HLLW treatment. Pt. 2
Energy Technology Data Exchange (ETDEWEB)
The results from a hot test, using authentic HLLW solution, of the CTH actinide separation process are reported. The process consists of three solvent extraction cycles for separation of actinides and technetium from reprocessing high level liquid waste, utilizing HDEHP, TBP, and HDEHP in sequence, and an optional step for sorption on inorganic ion exchangers of the fission product content in the process raffinate. In general the process worked according to predictions but a malfunctioning feed pump gave a 10% loss of Pu to one stream. The hot test indicating that U and Pu can be recovered with losses below 0.1% and Am, Cm with a loss below 0.2%. Np and Tc were difficult to follow because of the low activity of /sup 237/Np and because /sup 99/Tc is a pure beta emitter, but the results indicate that also these elements behaved according to predictions, i.e., that recoveries >= 99.8% for Np and >= 97% for Tc can be achieved. For the HLLW stream the solvent ...
1984-01-01
Benign and malign pulmonary tumors in childhood; Benigne und maligne Lungentumoren im Kindesalter
Energy Technology Data Exchange (ETDEWEB)
Pulmonary tumors in children are rare. Nevertheless, there are besides malign primary neoplasms and metastases also some benign tumors that the radiologist should know. The identification of some tumors is difficult, since some of them may mimic pulmonary inflammation. The first diagnostic tool is chest radiography. After that, a CT with contrastmedium should be performed, if possible a multislice-CT (MSCT). Identification of mediastinal structures is best with MRI. (orig.) [German] Tumoren der Lunge sind im Kindesalter selten. Trotzdem finden sich neben den malignen primaeren und sekundaeren Raumforderungen auch im Kindesalter immer wieder benigne Tumoren, die der Radiologe kennen sollte. Eine eindeutige Identifizierung kann schwierig sein, da z. B. entzuendliche Infiltrate vorgetaeuscht werden koennen. Die primaere Untersuchungsmethode ist das konventionelle Thoraxroentgen. Die weitere Diagnostik muss mit der Computertomographie, nach Moeglichkeit mit einem ...
2003-12-01
Automation in a material processing/storage facility
Energy Technology Data Exchange (ETDEWEB)
The Savannah River Site (SRS) is currently developing a new facility, the Actinide Packaging and Storage Facility (APSF), to process and store legacy materials from the United States nuclear stockpile. A variety of materials, with a variety of properties, packaging and handling/storage requirements, will be processed and stored at the facility. Since these materials are hazardous and radioactive, automation will be used to minimize worker exposure. Other benefits derived from automation of the facility include increased throughput capacity and enhanced security. The diversity of materials and packaging geometries to be handled poses challenges to the automation of facility processes. In addition, the nature of the materials to be processed underscores the need for safety, reliability and serviceability. The application of automation in this facility must, therefore, be accomplished in a rational and disciplined manner to satisfy the strict operational requirements of the facility. ...
1997-05-01
Aspects of the development of mechanical superchargers; Aspekte der Entwicklung mechanischer Lader
Energy Technology Data Exchange (ETDEWEB)
Internal combustion engines with mechanically driven superchargers are known for good performance at low engine speeds and fast response times under fluctuating loads. Application engineers can choose between superchargers with and without internal compression - the familiar roots (blower) type or true compressors - for supercharging an internal combustion engine. This article by DaimlerChrysler describes two options for improving the partial load behaviour of mechanically supercharged internal combustion engines with compressors. (orig.) [German] Die Aufladung mit mechanisch angetriebenen Verdraengerladern zeichnet sich durch guten Druckaufbau bei niedrigen Drehzahlen und gute Dynamik bei Lastwechseln aus. Fuer die Applikation am Verbrennungsmotor koennen Maschinen ohne innere Verdichtung - wie die bekannten Roots-Geblaese - oder Maschinen mit innerer Verdichtung - Kompressoren im eigentlichen Sinne - zum Einsatz kommen. In diesem Beitrag von DaimlerChrysler sind ...
2001-11-01
Antideuterons from Dark Matter Decay
Recent observations of a large excess of cosmic-ray positrons at high energies have raised a lot of interest in leptonic decay modes of dark matter particles. Nevertheless, dark matter particles in the Milky Way halo could also decay hadronically, producing not only a flux of antiprotons but also a flux of antideuterons. We show that for certain choices of parameters the antideuteron flux from dark matter decay can be much larger than the purely secondary flux from spallation of cosmic rays on the interstellar medium, while the total antiproton flux remains consistent with present observations. We show that if the dark matter particle is sufficiently light, the antideuteron flux from dark matter decay could even be within the reach of planned experiments such as AMS-02 or GAPS. Furthermore, we discuss the prospects to observe the antideuteron flux in the near future if the steep rise in the positron fraction reported by the PAMELA collaboration is interpreted in ...
2009-01-01
Antideuteron fluxes from dark matter annihilation in diffusion models
Antideuterons are among the most promising galactic cosmic ray-related targets for dark matter indirect detection. Currently only upper limits exist on the flux, but the development of new experiments, such as GAPS and AMS-02, provides exciting perspectives for a positive measurement in the near future. In this Paper, we present a novel and updated calculation of both the secondary and primary antideuteron fluxes. We employ a two-zone diffusion model which successfully reproduces cosmic-ray nuclear data and the observed antiproton flux. We review the nuclear and astrophysical uncertainties and provide an up to date secondary (i.e. background) antideuteron flux. The primary (i.e. signal) contribution is calculated for generic WIMPs annihilating in the galactic halo: we explicitly consider and quantify the various sources of uncertainty in the theoretical evaluations. Propagation uncertainties, as is the case of antiprotons, are sizeable. Nevertheless, antideuterons ...
2008-01-01
Energy Technology Data Exchange (ETDEWEB)
Isobaric contaminants are often problematical in accelerated negative ion beams for research at certain radioactive ion beam (RIB) and accelerator mass spectrometry (AMS) facilities since their presence in low-intensity rare isotopic beams seriously compromise experimental results. This article describes a non-resonant, laser-based photo-detachment apparatus for use at these facilities, which, according to calculations efficiently removes isobaric contaminants from these beams. The advantage of the system for isobaric contaminant removal over other systems proposed to date lies in its ability to efficiently capture easily transportable energetic negative ion beams with low, intermediate or high energy spreads by a superconducting solenoid magnetic field. The ability to change the diameter of captured beams by adjusting the magnetic field strength permits optimum control of the radial overlap of the laser/negative ion beam profiles over an extended interaction ...
2008-09-01
Americium and curium total half-lives and for the spontaneous fission branch
Energy Technology Data Exchange (ETDEWEB)
The long-lived nuclides of the americium and 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. These preliminary estimates for the half-lives were given previously. Efforts continue to reevaluate the various experiments to better gauge the systematic errors involved and reassess the total ...
1985-01-01
Actinides produced by /sup 12/C + /sup 242/Pu and /sup 16/O + /sup 238/U reactions
Energy Technology Data Exchange (ETDEWEB)
The cross sections for /sup 250/Fm, /sup 244-246/Cf, /sup 242-244/Cm, and /sup 242/Am/sup g-italic/ produced by the /sup 12/C+ /sup 242/Pu and the /sup 16/O+ /sup 238/U reactions leading to the same compound nucleus of /sup 254/Fm have been measured by using radiochemical methods. The excitation functions show that the difference between the /sup 12/C+ /sup 242/Pu and the /sup 16/O+ /sup 238/U reactions can be attributed mainly to the Coulomb barriers. Our results were compared with others reported previously for /sup 22/Ne+ /sup 232/Th, /sup 12/C+ /sup 238/U, /sup 12/C+ /sup 240,241/Pu, /sup 13/C+ /sup 241/Pu, /sup 16/O+ /sup 233/U, and /sup 16/O+ /sup 242/Pu reaction systems, and support a mechanism involving transfer of ..cap alpha..-particle clusters (C,Be,He) from projectile to target for the production of Cf and Cm isotopes.
1986-09-01
Actinides produced by /sup 12/C + /sup 242/Pu and /sup 16/O + /sup 238/U reactions
International Nuclear Information System (INIS)
The cross sections for /sup 250/Fm, /sup 244-246/Cf, /sup 242-244/Cm, and /sup 242/Am/sup g/ produced by the /sup 12/C+ /sup 242/Pu and the /sup 16/O+ /sup 238/U reactions leading to the same compound nucleus of /sup 254/Fm have been measured by using radiochemical methods. The excitation functions show that the difference between the /sup 12/C+ /sup 242/Pu and the /sup 16/O+ /sup 238/U reactions can be attributed mainly to the Coulomb barriers. Our results were compared with others reported previously for /sup 22/Ne+ /sup 232/Th, /sup 12/C+ /sup 238/U, /sup 12/C+ /sup 240,241/Pu, /sup 13/C+ /sup 241/Pu, /sup 16/O+ /sup 233/U, and /sup 16/O+ /sup 242/Pu reaction systems, and support a mechanism involving transfer of #alpha#-particle clusters (C,Be,He) from projectile to target for the production of Cf and Cm isotopes.
Transfer of elements into mother's milk; Transfer von Elementen in die Muttermilch
Energy Technology Data Exchange (ETDEWEB)
This research project aimed to determine the factors for the transfer of the elements silver (Ag), cerium (Ce), cobalt (Co), chrome (Cr), gallium (Ga), lanthanum (La), molybdenum (Mo), niobium (Nb), radium (Ra), ruthenium (Ru), antimony (sb), thorium (Th), titanium (Ti) and uranium (U) from food into the mother's milk. This factors will be used as a basic to check and derive activity values for the contamination of food and for radiation protection at working places of suckling women. For this purpose 19 mothers collected samples daily (2-8 weeks), using the duplicate method, of all the food they consumed as well as of their milk. After microwave-assisted digestion the element contents were analysed by mass-spectroscopy with inductive coupled plasma (ICP-MS). The results of the mothers who participate for more than 5 weeks were used to make a time lapse between the intake and transfer of the elements in the mothers milk visible. (orig.) [German] Ziel dieses Forschungsvorhabens ...
2000-08-01
Energy Technology Data Exchange (ETDEWEB)
On account of a raised appearing of plastic waste and shreddered light fraction (SLF) from old car utilization as well as legal handicaps experiments were carried out at the Institute of Ferrous Metallurgy (RWTH Aachen) on a laboratory rig to inject DSD (Duales System Deutschland)-plastic waste and SLF with the destination of a subsequent raw material utilization in the blast furnace and cupola furnace. The experiments on the laboratory rig with DSD plastics could verify that by injection of specific coal/plastic mixtures into the blast furnace the injection rate could be raised by an improvement in the conversion degree and therefore the amount of the inserted reducing agent can be lowered. The injection of SLF without reduction of the inert materials and of the contents on alloying elements and/or tramp elements by extensive preparation has no advantages according to the experiments for the blast furnace process. Pilot experiments on the cupola furnace showed that, assuming a certain ...
1996-01-01
Energy Technology Data Exchange (ETDEWEB)
In the future even more than in the past, nuclear power will be indispensable in the present industrialized countries and in those still under development. The safe, nonpolluting, and economic supply of energy to mankind in the future includes so many different problems that the technology of the high-temperature reactor at its present level of development, and with the possibilities is offers above and beyond those provided by other, established, technologies, does not have to mark the end of some old line of development, but rather should be seen as the starting point of a development offering promise for the future. It is for this very reason that the extensive, valuable knowledge and experience accumulated in the construction, operation, and decommissioning of the AVR and THTR plants, the development of the HTR module and other variants and, last, but not least, the valuable results of projects such as PNP, NFE, and HHT, must be preserved at the research centers and with former ...
1996-08-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: The determination of tumor volume in ocular tumors is very important for the planning and success of radiation therapy. This study uses an animal model to evaluate the accuracy of MR-based volumetry of ocular tumors. Materials and methods: In a total of 25 porcine eyes obtained from the slaughterhouse, ocular tumors were produced by injecting a mixture of hand creme and Gd-DTPA under ophthalmoscopic guidance. The injected volume varied between 0.05 ml and 2.7 ml. The eyes were examined with a 1.5 Tesla scanner and a 4 cm circular surface coil especially developed for ocular MRI. After data transfer to a separate workstation, volumetric analysis was carried out by three independent radiologists using semiautomated software. The determined volume was compared with the injected volume. Results: Of the 25 prepared porcine eyes, 23 were suitable for volumetric analysis. The injection of the mixture of hand creme and GD-DTPA produced two different types of tumors. ...
2003-07-01
Drying plant waste; Trocknung von Betriebsabfaellen
Energy Technology Data Exchange (ETDEWEB)
Under the repository storage conditions of Eram and Konrad, waste packages designed for permanent storage must not contain or release freely mobile liquids, except for the minimum residues attainable by reasonable efforts or unavoidable. In accordance with a directive issued by the German Federal Ministry for the Environment (BMU), waste conditioning must be carried out so as to minimize waste volumes and, if possible, on the site where the waste arises. Liquid waste is conditioned most effectively by drying. At the present time, various different processes for drying liquid waste are employed as reflected by the state of the art: The Robe process; roller drying; the RDA process; Favorit; in-drum drying; and HPA liquid waste drying with make-up feed. The HPA process offers these advantages: Drying under atmospheric conditions, which means high level of dryness (freely mobile and releasable water is removed); the residual water content is 10%; isothermal drying by hot air, which ...
1995-11-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: The aim of this study was to evaluate the accuracy of MRI in the measurement of cartilage thickness of the ankle joint in comparison to pathologic and histologic specimens. Patients and methods: The ankle joints of four fresh cadaver feet were imaged on a 1.5 T MR-unit in the coronal plane. Standard T{sub 1}-weighted spin echo (SE) and a T{sub 1}-weighted 3D-GE (FLASH-3D) sequence with fat saturation were applied. Following MR imaging, the talus was explanted and cut parallel to the MR images for macroscopic evaluation and histologic specimens were prepared. MRI measurements of the cartilage thickness of the talus were carried out in two ways: Without and with consideration of a transition zone of intermediate signal intensity between hyperintense cartilage and hypointense cortical bone. The data were compared with the anatomic specimens as the gold standard expressing the difference as a percentage value. On histologic specimens thickness of deep calcified cartilage layer was ...
1997-04-01
International Nuclear Information System (INIS)
1 - Description of program or function: MCB-JEF2.2 is a continuous-energy cross section libraries in ACE Format suitable for the MCB-1C and MCNP codes. Libraries for various materials were generated at six different Temperatures, and cover the energy range up to 20 MeV. Format: ACE. Number of groups: Continuous energy. Nuclides: H-1, H-2, H-3, He-3, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-nat., N-14, N-15, O-16, O-17, Na-23, F-19, Mg-nat., Al-27, Si-nat., P-31, S-32, S-33, S-34, S-36, Cl-nat, K-nat, Ca-nat., Ti-nat, V-nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-59, Ni-60, Ni-61, Ni-62, Ni-64, Cu-nat, Ga-nat, Ge-72, Ge-73, Ge-74, Ge-76, As-75, Se-74, Se-76, Se-77, Se-78, Se-80, Se-82, Br-79, Br-81, Kr-78, Kr-80, Kr-82, Kr-83, Kr-84, Kr-85, Kr-86, Rb-85, Rb-86, Rb-87, Sr-84, Sr-86, Sr-87, Sr-88, Sr-89, Sr-90, Y-89, Y-90, Y-91, Zr-nat, Zr-90, Zr-91, Zr-92, Zr-93, Zr-94, Zr-95, Zr-96, Nb-93, Nb-94, Nb-95, Mo-nat, Mo-92, Mo-94, Mo-95, Mo-96, Mo-97, ...
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, 56-Ba-138, 59-Pr-141, ...
Energy Technology Data Exchange (ETDEWEB)
It has often been proposed that track diameter in etched detectors can be used for energy spectrometry. To test this proposition, the relationship between track diameter and energy of alpha particles, in the range 0.1-5.5 MeV, incident on CR-39 was studied. Two sets of detectors were irradiated by a collimated normally-incident beam of {alpha}-particles of different energies, using an Am-241 source. Different foils of the first set were etched for variable lengths of time in such a way that, in each case, the etchant reached the end of the latent track. Foils in the second set were etched for a fixed 'short' time of 2 h, for all {alpha}-energies. The linear rate of energy loss as well as the residual range of {alpha}-particles was determined by using Henke and Benton's computer program. It is found that, for 'short' etching times, the track diameter mimics the 'Bragg curve', i.e., at first it rises with ...
1999-02-01
Energy Technology Data Exchange (ETDEWEB)
K{beta}-to-K{alpha} X-ray intensity ratios of Ti, Cr, Fe and Co in pure metals and in Cr{sub 0.26}Fe{sub 0.74}, Cr{sub 0.80}Co{sub 0.20} and Ti{sub 0.80}Cr{sub 0.20} alloys have been measured following excitation by 59.54 keV {gamma}-rays from a 7400 MBq (200 mCi) {sup 241}Am point-source. The valence electronic structure of Ti, Cr, Fe and Co in the samples have been evaluated by the comparison of the measured K{beta}-to-K{alpha} intensity ratios with the results of multiconfiguration Dirac-Fock calculations performed for various electronic configurations of these metals. The 3d-electron populations obtained for pure metallic Ti, Cr, Fe and Co agree well with the results of band structure calculations of Papaconstantopoulos (Handbook of band structure of elemental solids, Plenum Press, New York, 1986). Our analysis indicates significant increase of 3d-electron population of Ti, Cr and Fe in the alloys with respect to the pure metals, except for Cr in Cr{sub ...
2002-10-01
International Nuclear Information System (INIS)
K#beta#-to-K#alpha# X-ray intensity ratios of Ti, Cr, Fe and Co in pure metals and in Cr_0_._2_6Fe_0_._7_4, Cr_0_._8_0Co_0_._2_0 and Ti_0_._8_0Cr_0_._2_0 alloys have been measured following excitation by 59.54 keV #gamma#-rays from a 7400 MBq (200 mCi) "2"4"1Am point-source. The valence electronic structure of Ti, Cr, Fe and Co in the samples have been evaluated by the comparison of the measured K#beta#-to-K#alpha# intensity ratios with the results of multiconfiguration Dirac-Fock calculations performed for various electronic configurations of these metals. The 3d-electron populations obtained for pure metallic Ti, Cr, Fe and Co agree well with the results of band structure calculations of Papaconstantopoulos (Handbook of band structure of elemental solids, Plenum Press, New York, 1986). Our analysis indicates significant increase of 3d-electron population of Ti, Cr and Fe in the alloys with respect to the pure metals, except for Cr in Cr_0_._2_6Fe_0_._7_4 where ...
2002-10-01
Treatment of low-frequency pulsating magnetic field on amorphous alloy Fe{sub 78}Si{sub 9}B{sub 13}
Energy Technology Data Exchange (ETDEWEB)
Effect of low-frequency pulsating magnetic field on the microstructure and magnetic properties of amorphous alloy Fe{sub 78}Si{sub 9}B{sub 13} were investigated. The temperature rise induced by the treatment was measured by a non-contact infrared thermometer. The crystallization behavior and microstructure of specimens were studied by Moessbauer spectroscopy and transmission electron microscope (TEM). Magnetic properties of the specimens were investigated by alternating gradient magnetometer (AGM). The results show that the low-frequency pulsating magnetic field can promote the single-phase crystallization of amorphous alloy Fe{sub 78}Si{sub 9}B{sub 13}. The frequency, f of applied field is from 10 to 40 Hz, magnetic field, H is from 0.02 to 0.04 T and treatment duration, t is from 180-300 s. The volume fraction of crystallization phase ({alpha}-Fe(Si), the grain size, 2-10 nm) is 3-7%. The temperature rise less than 7 deg. C. Magnetic properties of samples are improved by magnetic ...
2007-07-15
Energy Technology Data Exchange (ETDEWEB)
This report describes the progress of the Dutch RAS programme on `Recycling and Transmutation of Actinides and Fission Products` over the year 1995, which is the second year of the 4-year programme 1994-1997. An extensive listing of reports and publications from 1991 to 1995 is given. Highlights in 1995 were: -The completion of the European Strategy Study on Nuclear Waste Transmutation as a result of which the understanding of transmutation of plutonium, minor actinides and long-lived fission products in thermal and fast reactors has been increased significantly. Important ECN contributions were given on Am, {sup 99}Tc and {sup 129}I transmutation options. Follow-up contracts have been obtained for the study of 100% MOX cores and accelerator-based transmutation. - Important progress in the evaluation of CANDU reactors for burning very large amounts of transuranium mixtures in inert matrices. - The first RAS irradiation experiment in the HFR, in which the ...
1996-04-01
Energy Technology Data Exchange (ETDEWEB)
The translocation of particles from the alveolar compartment to the pleural space and tracheobronchial lymph nodes was investigated in rats over a 30 day period following the intrapulmonary instillation of 4 x 10/sup 8/ polystyrene microspheres (1.9 ..mu..m dia.). In initial studies, approx. =10/sup 4/ particles were found in the pleural space compartment on Days 1, 14 and 30 after particle deposition, and most of these were cell-associated. Subsequent pleural space studies indicated, however, that the particles found in this compartment were, at least in part, due to the pleural lavage technique, and, unlike observations reported for some fibers, the translocation of the particles used in our study to the pleural space does not represent an important lung clearance pathway. In regard to particle clearance to the tracheobronchial lymph nodes, the accumulation of particles, most of which were extracellular, kinetically was biphasic with the most rapid phase occurring within the first 24 ...
1985-01-01
Energy Technology Data Exchange (ETDEWEB)
On the 28{sup th} of May in 1998, the regulation of the ''Application of roof bolt support in coal mines'' came into force. Afterwards, the new roof bolt permission guidelines have been worked out by the Landesoberbergamt (Inspectorate of mines) in co-operation with the Deutsche Montan Technologie GmbH, with the Deutsche Steinkohle AG and with bolt manufacturers. These guidelines have been put into force on the 31{sup st} of August in 2000. Topics of this paper are the new regulation and first experiences. (orig.) [German] Nach der Erarbeitung der ''Richtlinien ueber die Verwendung von Ankerausbau im Steinkohlenbergbau (Anker-Richtlinien)'' vom 28. Mai 1998 wurden unverzueglich auch die ''Richtlinien ueber die Genehmigung von Ankerausbau (Ankergenehmigungs-Richtlinien)'' in Angriff genommen. Diese Richtlinien, die das Landesoberbergamt NRW gemeinsam mit Fachleuten der Deutschen ...
2001-07-01
Energy Technology Data Exchange (ETDEWEB)
Many features from the background for an intensified application of fracture mechanics concepts in many industries world-wide. These include requirements for a permanent increase of the level of performance of technical components and structures by the introduction of new materials, joining technologies and design principles, the problem of ageing components and life extension, an increased emphasis on non-destructive in-service inspection combined with improved NDT techniques, and also a number of failure events caused by fatigue and fracture The aim of the present paper is to give a brief state-of-the-art review on how fracture mechanics is applied in different industrial branches today. This is based on standards and guidelines in the aerospace industry, in the nuclear and fossil power generation, in the chemical and petrochemical and the pipeline industry, in civil engineering, offshore technique and other fields. Based on the review an outlook is given on a future development that ...
2000-07-01
Energy Technology Data Exchange (ETDEWEB)
We have developed refined statistical and modeling techniques to assess low-level uptake and urinary excretion of plutonium from different population group in the northern Marshall Islands. Urinary excretion rates of plutonium from the resident population on Enewetak Atoll and from resettlement workers living on Rongelap Atoll range from <1 to 8 {micro}Bq per day and are well below action levels established under the latest Department regulation 10 CFR 835 in the United States for in vitro bioassay monitoring of {sup 239}Pu. However, our statistical analyses show that urinary excretion of plutonium-239 ({sup 239}Pu) from both cohort groups is significantly positively associated with volunteer age, especially for the resident population living on Enewetak Atoll. Urinary excretion of {sup 239}Pu from the Enewetak cohort was also found to be positively associated with estimates of cumulative exposure to worldwide fallout. Consequently, the age-related trends in urinary excretion of ...
2007-05-01
Status of the WAND (Waste Assay for Nonradioactive Disposal) project as of July 1997
Energy Technology Data Exchange (ETDEWEB)
The WAND (Waste Assay for Nonradioactive Disposal) system can scan thought-to-be-clean, low-density waste (mostly paper and plastics) to determine whether the levels of any contaminant radioactivity are low enough to justify their disposal in normal public landfills or similar facilities. Such a screening would allow probably at least half of the large volume of low-density waste now buried at high cost in LANL`s Rad Waste Landfill (Area G at Technical Area 54) to be disposed of elsewhere at a much lower cost. The WAND System consists of a well-shielded bank of six 5-in.-diam. phoswich scintillation detectors; a mechanical conveyor system that carries a 12-in.-wide layer of either shredded material or packets of paper sheets beneath the bank of detectors; the electronics needed to process the outputs of the detectors; and a small computer to control the whole system and to perform the data analysis. WAND system minimum detectable activities (MDAs) for point sources range from ...
1998-03-01
Energy Technology Data Exchange (ETDEWEB)
The high-strength and ultra high-strength steels developed and produced by Thyssen Krupp Stahl make a major contribution to automotive lightweighting. Proven and newly-developed coatings are used to meet increasingly important corrosion protection requirements. Design for materials, optimized forming and joining processes and the use of modern simulation techniques help to exploit the potential of the new steels. Future development work will focus on reducing the density of steels without compromising their well-known advantages - in particular their strength. The use of high-strength and ultra high-strength steels in the automotive industry is on the increase. Steel will remain the material of choice for auto manufacture, above all due to its potential for cost-efficient lightweight construction and its full recyclability. (orig.) [German] Einen wesentlichen Beitrag zum Leichtbau im Automobil leisten die von Thyssen Krupp Stahl entwickelten und hergestellten hoeher- und hoechstfesten ...
1999-04-01
Energy Technology Data Exchange (ETDEWEB)
In a case study of the River Lahn, Hessen, Germany, the ecological impact of effluents from sewage treatment plants was investigated. These emissions have a significant impact on the receiving water quality with ammonia, nitrite, phosphorus and the eutrophication as most important factors. Current legislation standards seem to be sufficent for the sanitation of the nitrogen load. The potential of phosphorus removal in sewage treatment plants however may not reach the demand for eutrophication abatement. Therefore, integrated and immission oriented strategies are required including in site measures of river restoration. (orig.) [Deutsch] An der hessischen Lahn wurde in einem mehrjaehrigen Forschungsvorhabens die Bedeutung von Abwasserereinleitungen aus Klaeranlagen hinsichtlich ihrer gewaesseroekologischen Relevanz untersucht. Wesentliche Belastungen beziehen sich auf die Parameter Ammonium, Nitrit und Phosphor sowie eutrophierungsbedingte Folgeerscheinungen. Waehrend bei den ...
1995-12-01
Energy Technology Data Exchange (ETDEWEB)
Clinical information is indispensable for swift and cost-effective clarification of diseases of the larynx. While quality clarification of neurological changes in the area of the posterior cranial fossa and in the course of the vagus nerve as a cause of glottis malfunction is possible with MRI, localized disease of the larynx can more effectively be assessed with low-artifact CT. In the particularly difficult assessment of the post-operative larynx, a recurrence can be diagnosed only after a baseline study has been carried out after the end of therapy. With knowledge of the pretherapeutic findings, the findings immediately post-therapy, and the operation technique used, the optimal CT examination, which can be carried out quickly, will be able to provide more information about recurrence. (orig.) [Deutsch] Zur schnellen und kostenguenstigen Abklaerung von Erkrankungen des Larynx ist die klinische Information unabdingbar: Wenn neurologische Veraenderungen im Bereich der hinteren ...
1998-02-01
Energy Technology Data Exchange (ETDEWEB)
RangerMaster{trademark} is the embedded firmware for Quantrad Sensor`s integrated nuclear instrument package, the Ranger{trademark}. The Ranger{trademark}, which is both a gamma-ray and neutron detection system, was originally developed at Los Alamos National Laboratory for in situ surveys at the Plutonium Facility to confirm the presence of nuclear materials. The new RangerMaster{trademark} software expands the library of isotopes and simplifies the operation of the instrument by providing an easy mode suitable for untrained operators. The expanded library of the Ranger{trademark} now includes medical isotopes {sup 99}Tc, {sup 201}Tl, {sup 111}In, {sup 67}Ga, {sup 133}Xe, {sup 103}Pa, and {sup 131}I; industrial isotopes {sup 241}Am, {sup 57}Co, {sup 133}Ba, {sup 137}Cs, {sup 40}K, {sup 60}Co, {sup 232}Th, {sup 226}Ra, and {sup 207}Bi; and nuclear materials {sup 235}U, {sup 238}U, {sup 233}U, and {sup 239}Pu. To accomplish isotopic identification, a simulated ...
1998-12-31
Antiquitin (ATQ) deficiency is the main cause of pyridoxine dependent epilepsy characterized by early onset epileptic encephalopathy responsive to large dosages of pyridoxine. Despite seizure control most patients have intellectual disability. Folinic acid responsive seizures (FARS) are genetically identical to ATQ deficiency. ATQ functions as an aldehyde dehydrogenase (ALDH7A1) in the lysine degradation pathway. Its deficiency results in accumulation of ?-aminoadipic semialdehyde (AASA), piperideine-6-carboxylate (P6C) and pipecolic acid, which serve as diagnostic markers in urine, plasma, and CSF. To interrupt seizures a dose of 100mg of pyridoxine-HCl is given intravenously, or orally/enterally with 30mg/kg/day. First administration may result in respiratory arrest in responders, and thus treatment should be performed with support of respiratory management. To make sure that late and masked response is not missed, treatment with oral/enteral pyridoxine should be continued until ATQ ...
2011-05-24
Pulse height response of Si surface barrier detectors to 5-70 MeV heavy ions
Energy Technology Data Exchange (ETDEWEB)
An extensive series of pulse height measurements have been performed in partially depleted Si surface barrier detectors, using various heavy ions (Li, B, C, O, Al and Cl), at energies between 5 and 70 MeV. After correcting for the small energy loss of the incident ions in traversing the gold surface barrier layer of the detector and for the residual nuclear stopping, the resulting pulse heights per MeV for the various heavy ions were found to be up to 2.5% larger than for the {sup 241}Am (5.486 MeV) alpha particle. This increase, although significant, is smaller than had been anticipated from an extrapolation of the earlier study of H, He and Li pulse heights by Lennard et al.. A new method of analysis of pulse height data, which significantly reduces the uncertainties associated with the dead layer energy loss and nuclear stopping corrections, was used in order to determine directly the variation of the average energy for electron-hole pair creation with ...
1992-04-01
Properties of plutonium-contaminated particles resulting from British Vixen B trials at Maralinga
International Nuclear Information System (INIS)
Since 1984 a number of studies have been performed to investigate residual contamination at the former atomic weapons test site at Maralinga in South Australia, and to aid in the rehabilitation of the area. The largest site of plutonium contamination at Maralinga results from twelve Vixen B trials conduced at Taranaki in 1960, 1961 and 1963. Plutonium was dispersed along four major plumes from these trials. Measurements of the ratios of activities of "2"3"9Pu and "2"4"0Pu to "2"4"1Am are presented for the plumes. These are identified with individual trials where possible. Some measurements have also been made of "2"3"5U activities. An examination of meteorological and health physics survey data suggests that the most extensive part of the north-west plume results from a single trial, viz. Vixen B2 round 5 of 1961. It appears that the level of contamination in this plume was augmented by rainout of material, and the extent of the plume was enhanced by the ...
1997-05-01
PRELIMINARY CROSS SECTION AND NU-BAR COVARIANCES FOR WPEC SUBGROUP 26
Energy Technology Data Exchange (ETDEWEB)
We report preliminary cross section covariances developed for the WPEC Subgroup 26 for 45 out of 52 requested materials. The covariances were produced in 15- and 187-group representations as follows: (1) 36 isotopes ({sup 16}O, {sup 19}F, {sup 23}Na, {sup 27}Al, {sup 28}Si, {sup 52}Cr, {sup 56,56}Fe, {sup 58}Ni, {sup 90,91,92,94}Zr, {sup 166,167,168,170}Er, {sup 206,207,208}Pb, {sup 209}Bi, {sup 233,234,236}U, {sup 237}Np, {sup 238,240,241,242}Pu, {sup 241,242m,243}Am, {sup 242,243,244,245}Cm) were evaluated using the BNL-LANL methodology. For the thermal region and the resolved and unresolved resonance regions, the methodology has been based on the Atlas-Kalman approach, in the fast neutron region the Empire-Kalman method has been used; (2) 6 isotopes ({sup 155,156,157,158,160}Gd and {sup 232}Th) were taken from ENDF/B-VII.0; and (3) 3 isotopes ({sup 1}H, {sup 238}U and {sup 239}Pu) were taken from JENDL-3.3. For 6 light nuclei ({sup 4}He, {sup 6,7}Li, {sup 9}Be, ...
2007-01-31
Nuclear radiation detectors on II-VI compounds
International Nuclear Information System (INIS)
Nuclear radiation detectors in integral execution were produced by successive epitaxial growth from vapor phase of Zn Te and Cd Se thin layers onto scintillating Zn Se (Te) crystals. The irradiation of combined Zn Se (Te) - Zn Te - Cd Se detectors by Cu_K_a X-rays leads to the appearance of photoreceiver e.m.f., which tends to saturation with the increase of X-ray radiation dose reaching the value of 0.34-0.40 V at 200 R/min. The short circuit current dependence of irradiation dose power is linear. The matching factor for detectors with Zn Te-Cd Se photoreceivers with different doping levels is 0.68-0.92. The absolute monochromatic sensitivity is 0.32-0.35 m A/m W at a quantum efficiency 0.58-0.61 and a time constant 2 x 10"-"4 s. The calculated dose sensitivity for Zn Se(Te)-Zn Te-Cd Se combined detectors at the irradiation with X-rays having effective energy 8.86 keV gives the value 3.9 x 10"-"7 A/cm"2 (R/min); the experimental value of dose sensitivity reaches ...
1993-10-13
Nickel base alloys for future steam turbines; Nickelbasis-Legierungen fuer zukuenftige Dampfturbinen
Energy Technology Data Exchange (ETDEWEB)
Modern commercial alloys are not suited for future steam turbines of operating temperatures beyond 700 C. {gamma}'-hardened alloys like Waspaloy have good mechanical characteristics but have defects when large batches are melted. {gamma}'/{gamma}''-hardened alloys like Inconel 706, on the other hand, are easy to produce but have insufficient microstructural long-term stability and insufficient creep strength. Mixed crystal solidified alloys like Inconel 617 have excessive yield stress at forging temperatures. Two new alloys were therefore developed. Results so far show that they have good production characteristics but insufficient mechanical characteristics. The reasons for this are currently under investigation. (orig.) [German] Die heutigen kommerziellen Legierungen sind nicht geeignet fuer den Einsatz in zukuenftigen Dampfturbinen mit Betriebstemperaturen oberhalb 700 C. {gamma}'-gehaertete Legierungen wie Waspaloy zeigen zwar gute ...
2003-07-01
New materials for future generations of III-V solar cells
Energy Technology Data Exchange (ETDEWEB)
Three- and four-junction III-V devices are proposed for ultrahigh-efficiency solar cells using a new 1-eV material lattice-matched to GaAs, namely, GaInNAs. We demonstrate working prototypes of a GaInNAs-based solar cell lattice-matched to GaAs with photoresponse down to 1 eV. Under the AM1.5 direct spectrum with all the light higher in energy than the GaAs band gap filtered out, the prototypes grown with base doping of about 10{sup 17}&hthinsp;cm{sup {minus}3} have open-circuit voltages ranging from 0.35 to 0.44 V, short-circuit current densities of 1.8 mA/cm{sup 2}, and fill factors from 61{percent} to 66{percent}. To improve on the current record-efficiency tandem GaInP/GaAs solar cell by adding a GaInNAs junction, the short-circuit current density of this 1-eV cell must be significantly increased. Because these low short-circuit current densities are due to short diffusion lengths, we have demonstrated a depletion-width-enhanced variation of one of the ...
1999-03-01
Energy Technology Data Exchange (ETDEWEB)
More than two and a half years of monitoring of a passive house school and day-care centre in Frankfurt a. M. show comfortable indoor climate and good air quality. The space heat consumption is low and shows savings of approximately 90 % as compared to average existing schools. Excellent performance was also achieved in terms of primary energy. The results of further analyses of the efficient ventilation system with heat recovery, the perimeter insulation as an alternative to floor slab insulation and the influence of the air change due to the entrance door are presented. (Abstract Copyright [2008], Wiley Periodicals, Inc.) [German] Ueber zweieinhalb Jahre Monitoring einer Passivhaus-Schule und Kindertagesstaette (KiTa) in Frankfurt a.M. zeigt behagliche raumklimatische Bedingungen bei guten Luftqualitaeten. Die Heizwaermeverbrauchswerte liegen wie erwartet niedrig und zeigen Einsparungen um 90 % gegenueber dem Durchschnitt im Bestand. Auch primaerenergetisch ...
2008-02-15
Mitochondrial sequestration of BCECF after ester loading in the giant alga Chara australis.
Ratiometric fluorescent dyes are often used to monitor free ion concentrations in vivo, especially in cells that are recalcitrant to transformation with genetically encoded fluorescent markers. Although intracellular dye distributions are often found to be cytosolic, dye localisation has often not been examined in detail. We began exploring the use of BCECF (2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein) to monitor pH in the giant alga Chara australis and discovered that younger leaf cells could be loaded using the acetoxymethyl ester of BCECF. However, we were puzzled to find in microphotometric measurements that the fluorescence ratio appeared insensitive to manipulations affecting cytosolic pH. Confocal imaging of C. australis cells loaded with BCECF showed an accumulation of the dye in two locations: (1) on the outside of the chloroplasts in irregularly shaped stationary bodies; (2) within 1-1.5 mum structures that moved rapidly with the pericellular cytoplasmic streaming. ...
2007-12-19
Energy Technology Data Exchange (ETDEWEB)
A high-temperature flow reactor and different technical plants were tested within the framework of this research project. Anthropogenic N{sub 2}O emissions form during secondary flue gas or waste gas purification as secondary emissions during denitrification and pollution abatement measures. N{sub 2}O forms as an intermediate product as NO is reduced to N{sub 2}. Under certain operating conditions N{sub 2}O is not decomposed completely. Different secondary flue gas purification measures, i.e. selective noncatalytic reduction (SNCR), selective catalytic reduction (SCR), and nonselective catalytic reduction (NSCR) were investigated testing several technical plants and the high-temperature flow reactor. (orig./EF) [Deutsch] Das Forschungsprojekt ``Messung der N{sub 2}O-Emissionen von Verbrennungsanlagen und Untersuchung von Moeglichkeiten zur Emissionsminderung`` wurde an einem Hochtemperatur-Stroemungsreaktor und an verschiedenen technischen Anlagen durchgefuehrt. Das anthropogen ...
1994-12-01
Measurement of relative L X-ray intensity ratio following radioactive decay and photoionization
Energy Technology Data Exchange (ETDEWEB)
The measurements of the L X-ray intensity ratio I(L{alpha})/I(L{beta}), I(L{alpha})/I(L{gamma}), I(L{alpha})/I(L{iota}), I(L{beta})/I(L{gamma}) and I(L{iota})/I(L{gamma}) for elements Dy, Ho, Yb, W, Hg, Tl and Pb were experimentally determined both by photon excitation, in which 59.5 keV {gamma}-rays from a filtered radioisotope {sup 241}Am was used, and by the radioactive decay of {sup 160}Tb, {sup 160}Er, {sup 173}Lu, {sup 182}Re, {sup 201}Tl, {sup 203}Pb and {sup 207}Bi. L X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the calculated theoretical values. Theoretical values of the I(L{alpha}/L{beta}), I(L{alpha}/L{gamma}), I(L{alpha}/L{iota}), I(L{beta}/L{gamma}) and I(L{iota}/L{gamma}) intensity ratios were calculated using theoretically tabulated values of subshell photoionization cross-section, fluorescence yield, fractional X-ray emission rates, Coster-Kronig transition ...
2008-05-22
Measurement of K x-ray intensity ratio of tin, gadolinium and dysprosium
International Nuclear Information System (INIS)
Full text: Measurement of K_#beta# to K_#alpha# x-ray intensity ratios are important not only in the field of atomic physics, radiation physics and medical physics, but also to test the validity of assumptions made in the theoretical prediction. The intensity ratios can also give information on the effect of physical and chemical environment of the element in the compound. Many investigators have adopted a single and double reflection geometries to measure the K_#beta# to K_#alpha# x ray intensity ratios to understand the effect of physical and chemical environment on x-ray fluorescence. The targets are excited by a radioactive source of having activity of the order 100 MBq. in order to carry out accurate measurement K_#beta# to K_#alpha# x-ray intensity ratios, we have develop 2#pi# geometrical configuration method : placing a target right on the surface of the detector facing the target to measure the K shell fluorescence parameters such as fluorescence yield, fluorescence cross ...
2003-11-01
M shell x-ray emission in Pb, Th and U due to L_3 to M sub shell transfer of vacancies
International Nuclear Information System (INIS)
M shell x-ray production cross sections in thick targets of Pb, Th and U by K x-rays of Rb, Nb and Mo respectively have been measured. As the incident K x-ray energies are above the L_3 edge but below L_2 edge energies of the respective target elements under reference, the M x-rays are produced not only due to direct interaction of incident photons with M shell electrons but also due to the shift of the L_3 subshell vacancies to the M shell. The experiment has been performed using a double reflection geometrical setup with a 1 Curie"2"4"1Am gamma ray source and a Si (Li) x-ray spectrometer. The measured values have been compared with those calculated using known values of M and L_3 subshell photoionisation cross sections and fluorescence yields etc., wherever possible. The component of the percentage contribution due to shift of L_3 subshell vacancies to M shell to the total M shell x-ray emission were evaluated and it is seen that the shift of vacancies from L_3 ...
Energy Technology Data Exchange (ETDEWEB)
In an extended case report, we discuss four cases with masses in the lacrimal fossa representing the most important entities in this region (lymphoma, pleomorphadenoma, inflammatory pseudotumor, and malignant epithelial tumor). The different indications for CT and MRI are explained. For the differential diagnosis of lacrimal gland lesions, the following imaging parameters are important: The shape of the lacrimal gland, the inner structure, the degree of contrast enhancement, and the surrounding bony structures. In the evaluation of the expansion of lacrimal gland lesions, CT in thin slices with multiplanar reconstructions is equal to MRI. However, the contrast-enhancement of lacrimal glands is better evaluated with MRI than with CT. The bony structures are better visualized on CT than on MRI. (orig.) [Deutsch] In einem erweiterten Fallbericht wird ueber die vier grossen Entitaeten bei Traenendruesenraumforderungen berichtet (Lymphom, pleomorphes Adenom, entzuendlicher Pseudotumor und ...
1995-11-01
International Nuclear Information System (INIS)
K#beta#-to-K#alpha# x-ray intensity ratios of Fe and Ni in pure metals and in Fe_xNi_1_-_x alloys (x=0.20, 0.50, 0.58) exhibiting similar crystalline structure have been measured following excitation by 59.54 keV #gamma# rays from a 200 mCi "2"4"1Am point source to understand why the properties of the Fe_xNi_1_-_x (x=0.2) alloy are distinct from other alloy compositions. The valence electronic structure of Fe and Ni in the samples has been evaluated by comparing the measured K#beta#-to-K#alpha# intensity ratios with the results of multiconfiguration Dirac-Fock calculations. Significant changes in the 3d electron population (with respect to the pure metal) are observed for Fe and Ni for certain alloy compositions. These changes can be explained by assuming rearrangement of electrons between 3d and (4s,4p) band states of the individual metal atoms. It has been found that the valence electronic structure of the Fe_0_._2Ni_0_._8 alloy is totally different from the ...
2001-02-15
Investigation by XRF and XRD of Zn and Fe in Fe{sub x} Zn{sub 1-x} thin films
Energy Technology Data Exchange (ETDEWEB)
Fe{sub x}Zn{sub 1-x} alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K{beta}/K{alpha} x-ray intensity ratios of Zn and Fe in Fe{sub x}Zn{sub 1-x} thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi {sup 241}Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in Fe{sub x}Zn{sub 1-x} thin films for different values of x. The reason for this change may be that the ...
2008-12-15
Investigation by XRF and XRD of Zn and Fe in Fex Zn1-x thin films
International Nuclear Information System (INIS)
FexZn1-x alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K?/K? x-ray intensity ratios of Zn and Fe in FexZn1-x thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi 241Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in FexZn1-x thin films for different values of x. The reason for this change may be that the electronegativity of iron is higher than that of zinc ...
2008-12-01
Energy Technology Data Exchange (ETDEWEB)
56 patients with the clinical diagnosis of sprained ankles were investigated. Evaluation of the anterior (AFTL) and posterior fibulotalar ligament (PFTL) was performed with the foot in dorsiflexion (20 ) and of the fibulo calcanear ligament (FCL) in plantarflexion (45 ). Axial T{sub 1}w-SE and T{sub 2}w-TSE images were obtained. Full-length visualisation of ligmaments in one slice and the extent of injury were evaluated. 12 ankle injuries were confirmed by operation. With MRI full-length visualisation of lateral ankle ligaments was possible in 86%. A partial/complete rupture of the AFTL was noticed in 33/64% and of the FCI in 29/39%, and of the PFTL in 27/5%. Sensitivity/specificity of MRI when compared to surgery was 100/100% for injuries of the AFTL, 64/100% for the FCL, and 33/78% for the PFTL. (orig./MG) [Deutsch] 56 Patienten wurden mit der klinischen Diagnose einer frischen Supinationsverletzung des oberen Sprunggelenkes untersucht. Das Lig. talofibulare anterius (TFA) und ...
1996-03-01
Energy Technology Data Exchange (ETDEWEB)
A high power (200KV), intense current density, low emittance (71mmmrad), high brightness (8x10{sup 10}A/m rad) electron beam was generated in the 10cm long, high-voltage-resistive multi-gap hollow cathode pseudospark chamber filled with 15pa nitrogen and driven by an improved pulse line accelerator. The beam was ejected with the 1mm diameter, the 2.2KA beam current, and the 400ns pulse length, and could propagated 20cm in the drift tube. At a distance of 5cm from the anode it penetrated consecutively an acid-sensitive discoloring film and a 0.05mm-thick copper foil both stuck closely, left 0.6mm and 0.3mm holes on them, respectively. That 10 shots on an acid-sensitive film produced a hole of 1.6mm at 7cm downstream of anode showed its good repeatability. After 60 shots the pseudospark discharge chamber was disassembled and observed that almost no destructive damage traces left on the surfaces of its various electrodes and insulators. But on almost all the surfaces ...
1995-12-31
Energy Technology Data Exchange (ETDEWEB)
The low budgets of local governments and Federal States in Germany as well as lack of financial means of renters delaying thorough modernisation of existing heating systems in residential and public buildings, novel heat supply and related customer services are emerging on the market. Heat supply companies and housing construction associations increasingly use modern electronics and telecommunication systems for heating system upgrading and reliable operation and maintenance. This option holds an enormous potential of saving money today and in the future. Installation of remote control and maintenance systems and the related telephone-based services offer fast repair and other services via electronic telecommunications systems, thus saving money and manpower for the repair services of heat suppliers or plumbers, or financial losses due to rents being docked for broken down heating systems. Such remote control and maintenance systems however need to be reasonable in price, and versatile ...
1997-11-01
Energy Technology Data Exchange (ETDEWEB)
In view of current trends in motor car development, the author investigates the increasing conflict between higher comfort and lower fuel consumption. The conflict results mainly from insufficient cooling water heating with consumption-optimized engines. So far, it was never necessary to analyze heat flow after cold starting and heat-up of the powertrain, to develop strategies for heat storage and distribution, to remove heat sinks and to use components multifunctionally. The contribution shows that a general heat management strategy for the whole vehicle will result in high potential fuel savings and improved thermal comfort. Using the example of a latent heat store, heating strategies for the engine and transmission system on the one hand and the passenger compartment on the other hand are developed, and the advantages are presented in detail. [German] Abgeleitet aus den Trends in der Fahrzeugentwicklung wird auf den immer staerker werdenden Konflikt zwischen den steigenden ...
1999-07-01
Expression of Na(+)-H+ exchange and ATP-dependent proton extrusion in growing rat IMCD cells
Energy Technology Data Exchange (ETDEWEB)
As the last step of urinary acidification, the inner medullary collecting duct (IMCD) is thought to secrete protons into the tubular lumens by means of a H(+)-translocating adenosinetriphosphatase (H(+)-ATPase). However, recent studies have also shown the existence of Na(+)-H+ exchange activity in IMCD cells. Although the physiological function of the antiporter in IMCD cells is unknown, activation of Na(+)-H+ exchange in other cell-culture systems has been suggested to be closely associated with the process of cell growth. Thus presence of Na(+)-H+ exchange may relate to the growth phase of these cells. To examine intracellular pH (pHi) regulation in growing IMCD cells, we studied proton transport by Na(+)-dependent and Na(+)-independent mechanisms by microfluorimetry using the pHi-sensitive dye 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein acetoxymethyl ester (BCECF/AM). Actively growing cells, defined by (3H)thymidine incorporations, ...
1990-03-01
Experience and recent developments in nuclear forensics at the Institute of Isotopes
International Nuclear Information System (INIS)
Full text: Based on experience with nuclear material confiscated in Hungary from illicit trafficking activities in the nineties it has been decided that traditional gamma-spectrometry should be complemented by destructive analytical techniques. The 17/1996 (I. 31.) Korm. Governmental Decree delegated the identification, categorization and characterization tasks to the Institute of Isotopes, Budapest. Routine gamma-spectrometric methods have been further developed aiming at the i) age (production date) determination of seized samples and complete (nondismountable) uranium-bearing items (such as fresh fuel bundles and fission chambers) by HRGS technique, ii) improvement of measurement accuracy and reliability. Starting in 2005 mass spectrometry (ICP-SFMS) and scanning electron microscopy have been implemented to characterize nuclear samples in more detail and to analyze environmental samples both for isotopic and elemental composition focusing on long-lived radioactive isotopes including ...
Engineering Technology Reports, Volume 2: Technology Base FY00
Energy Technology Data Exchange (ETDEWEB)
In FY-2000, Engineering at Lawrence Livermore National Laboratory faced significant pressures to meet critical project milestones, and immediate demands to facilitate the reassignment of employees as the National Ignition Facility (the 600-TW laser facility being designed and built at Livermore, and one of the largest R&D construction projects in the world) was in the process of re-baselining its plan while executing full-speed its technology development efforts. This drive for change occurred as an unprecedented level of management and program changes were occurring within LLNL. I am pleased to report that we met many key milestones and achieved numerous technological breakthroughs. This report summarizes our efforts to perform feasibility and reduce-to-practice studies, demonstrations, and/or techniques--as structured through our technology centers. Whether using computational engineering to predict how giant structures like suspension bridges will ...
2001-10-03
Emissions results for dedicated propane Chrysler minivans: the 1996 propane vehicle challenge
Energy Technology Data Exchange (ETDEWEB)
The U.S. Department of Energy (US DOE), through Argonne National Laboratory, and in cooperation with Natural Resources-Canada and Chrysler Canada, sponsored and organized the 1996 Propane Vehicle Challenge (PVC). For this competition , 13 university teams from North America each received a stock Chrysler minivan to be converted to dedicated propane operation while maintaining maximum production feasibility. The converted vehicles were tested for performance (driveability, cold- and hot-start, acceleration, range, and fuel economy) and exhaust emissions. Of the 13 entries for the 1996 PVC, 10 completed all of the events scheduled, including the emissions test. The schools used a variety of fuel-management, fuel-phase and engine-control strategies, but their strategies can be summarized as three main types: liquid fuel-injection, gaseous fuel-injection, and gaseous carburetor. The converted vehicles performed similarly to the gasoline minivan. The University of Windsor`s minivan had the ...
1997-02-01
Dose coefficients for intakes of radionuclides via contaminated wounds.
The NCRP Wound Model, which describes the retention of selected radionuclides at the site of a contaminated wound and their uptake into the transfer compartment, has been combined with the ICRP element-specific systemic models for those radionuclides to derive dose coefficients for intakes via contaminated wounds. These coefficients can be used to generate derived regulatory guidance (i.e., the activity in a wound that would result in an effective dose of 20 or 50 mSv, or in some cases, a organ-equivalent dose of 500 mSv) and clinical decision guidance (i.e., activity levels that would indicate the need for consideration of medical intervention to remove activity from the wound site, administration of decorporation therapy or both). Data are provided for 38 radionuclides commonly encountered in various activities such as nuclear weapons, fuel fabrication or recycling, waste disposal, medicine, research, and nuclear power. These include 3H, 14C, 32P, 35S, 59Fe, 57,58,60Co, 85,89,90Sr, ...
2011-05-01
Energy Technology Data Exchange (ETDEWEB)
Energy and angular double differential cross-section data of fragments by tens of MeV neutron or proton are important to evaluate dosimetry and radiation effect in devices or instruments, since fragments cause a large local ionization. Up to now, experimental data of the fragment production are very scarce due to experimental difficulties of fragment detection. A bragg curve spectrometer (BCS) for fragment measurement is a gridded-ionization chamber that identify fragments on the basis of the difference of Bragg peak value. The BCS was fabricated to adopt for fragment measurement in neutron-induced reactions and tested with a charged-particle beam and then applied to a neutron field successfully. The structure of BCS is a cylindrical gridded ionization chamber, and filled with a Ar + 10% CH{sub 4} gas at a pressure of 2.7 x 10{sup 4} Pa. To confirm the performance of BCS, the following tests were performed: 1) the saturation property by using {sup 241}Am {alpha} ...
2002-09-01
International Nuclear Information System (INIS)
Host matrices for actinide immobilisation will undergo the formation of large helium quantities due to alpha decay. Helium diffusion rate has to be known in order to predict the long-term behaviour of the material, and particularly, the influence of helium accumulation on mechanical properties. A nuclear reaction analysis method, namely the "3He(d, p)"4He reaction, has been used to analyse the evolution of "3He profiles after ion implantations at 1 and 3 MeV in two materials, monoclinic ZrO_2 (as a test material) and Ca_9Nd(PO_4)_5(SiO_4)F_1_._5(OH)_0_._5 britholite (envisaged for Am and Pu long-term storage). Two data processing methods are used: the classical excitation curve (proton yields versus deuteron energy) and second, the proton energy spectrum for a given deuteron energy. The characteristics of the "3He profiles (depth, width) obtained by both methods are compared to SRIM estimations. Their evolution during subsequent annealings allows an estimation of ...
2002-06-01
Determination of sodium in biological samples by instrumental neutron activation analysis
International Nuclear Information System (INIS)
Sodium is one of the most essential elements needed for metabolic processes amongst human beings. It is consumed in the form of sodium chloride but it is also present in edible plant leaves. Sodium is mostly analyzed by flame photometric method, a destructive and time consuming technique. Sodium has been determined in some green leave vegetables samples-palak, radish, khatta palak (ambat chuka), chaulai leaves, chauli bean covers and its seeds by instrumental neutron activation analysis. The method involves irradiation of samples with thermal neutrons from "2"4"1Am-Be source and counting "2"4Na activity (half life 15 hr) from the reaction "2"3Na(n,#gamma#) "2"4Na. Activity due to 1.37 MeV photopeak was counted with a NaI(Tl) crystal coupled to gamma ray spectrometer. Green leaves of the vegetables were thoroughly washed, dried at constant temperature and powdered. Bowen's Kale powder was used as standard for measuring sodium abundances. About 2g each of samples and ...
1981-05-01
Energy Technology Data Exchange (ETDEWEB)
The Jurua gas field is the first important hydrocarbon accumulation found in the jungle-covered Solimoes basin. The tectonic framework in this area is characterized by a right-lateral transpressional zone (Jurua structural trend). Hydrocarbon traps are anticlines developed along the upthrown block of a reverse fault. The prospective 2,200-m-thick Paleozoic section is unconformably covered by a 2,800-m-thick pile of Mesozoic and Cenozoic continental sediments. Anomalous concentrations of hydrocarbons (C{sub 2}-C{sub 4}) in soil samples are concordantly aligned with the trace of the reverse fault crossing the gas field, indicating that this feature acted as a conduit for hydrocarbon microseepage. Gas-producing wells are located over a tabular watershed which coincides with the northeast-southwest Jurua structural trend. An unsupervised classification of Landsat MSS data over the gas field area reveals that one spectral class of vegetation is aligned with the Jurua structural trend. Field ...
1990-05-01
Decontamination of LRW of low and intermediate level of activity with a new bio-sorbent mycoton
International Nuclear Information System (INIS)
An absorption method of elimination of liquid radioactive wastes (LRW) of low and intermediate activity level by decreasing their contamination up to the level permitting their discharge into the environment is proposed in the paper. The LRW decontamination is accompanied with efficient compacting the resulting secondary solid wastes. The method is based on the use of a new very efficient, chitin containing natural fiber bio-sorbent, Mycoton, which is manufactured commercially in Ukraine. The chemical composition of the sorbent and its highly developed surface provide practically unrestricted opportunities for producing its modifications having any necessary absorption and operational characteristics. The effects of pH, the presence of various salts and complexing agents, as well as of some other factors to the distribution coefficients of the most important radionuclides have been carefully studied in experiments with Mycoton and its modifications. It appeared, that the Mycoton based ...
2005-10-09
Energy Technology Data Exchange (ETDEWEB)
Pulmonary infections and tumors are a major cause of death in patients with AIDS. The combination of clinical, radiological, laboratory, and pathohistological data helps to narrow the spectrum of differential diagnoses or even allows a specific diagnosis in many patients. Nevertheless, an accurate diagnosis should be obtained as soon as possible during the clinical course of the illness to initiate treatment in time. Computed tomography (CT) has proven to provide promising results in the diagnosis of AIDS-related throacic diseases. The aim of this paper was to demonstrate the diagnostic capacities of CT in the context of particular AIDS-related thoracic pathologies. Additional information on the spectrum of pathological agents and on differential diagnostic signs is summarized. (orig.) [Deutsch] Pulmonale Infektionen und Tumore sind eine wesentliche Todesursache bei Patienten, die am erworbenen Immunmangelsyndrom AIDS leiden. In den meisten Faellen gelingt es, ...
1996-07-01
Energy Technology Data Exchange (ETDEWEB)
Two window layer materials, Al{sub 0.51}In{sub 0.49}P (E{sub g} = 2.3 eV) and Ga{sub 0.51}In{sub 0.49}P (E{sub g} = 1.88 eV) were compared for gas-source and solid-source MBE grown GaAs and Ga{sub 0.84}In{sub 0.16}As{sub 0.68}P{sub 0.32} (E{sub g} = 1.55 eV) solar cells. Due to the wider band-gap of Al{sub 0.51}In{sub 0.49}P, the increased spectral response was observed for both GaAs and Ga{sub 0.84}In{sub 0.16}As{sub 0.68}P{sub 0.32} material based solar cells. In the case of the GaAs cells, the short-circuit current density was observed to increase from 32.5 mA/cm{sup 2} to 34.4 mA/cm{sup 2} with the Al{sub 0.51}In{sub 0.49}P window layer at AM0. Similar improvement was observed for the Ga{sub 0.84}In{sub 0.16}As{sub 0.68}P{sub 0.32} solar cells.
1997-12-31
Energy Technology Data Exchange (ETDEWEB)
A considerable fraction of radioactivity entering the environment from different nuclear events is associated with particles. The impact of these events can only be fully assessed where there is some knowledge about the mobility of particle bound radionuclides entering the environment. The behavior of particulate radionuclides is dependent on several factors, including the physical, chemical and redox state of the environment, the characteristics of the particles (e.g., the chemical composition, crystallinity and particle size) and on the oxidative state of radionuclides contained in the particles. Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized using non-destructive analytical and microanalytical methods. By determining the activity of {sup 239,240}Pu and {sup 241}Am isotopes from their gamma peaks structural information related to Pu matrix was obtained, and the source term was revealed. Composition and ...
2005-06-11
Energy Technology Data Exchange (ETDEWEB)
High-strength, fully hardening steels are used in general for applications involving severe wear and frequently also additional cyclic stress. For the latter condition, the available information and experimental data for component dimensioning are insufficient. Work reported in the dissertation therefore was intended to establish experimental information showing the performance of the bainitic roller bearing steel 100Cr6 and deducing rules of applicability to components, of the fatigue strength data obtained with the specimens. Various models for calculating the fatigue strength are presented together with their application to the steel 100Cr6. The results show that the weakest link model is a good concept for fatigue strength calculation, taking into account multiaxial loading. (orig/CB) [Deutsch] Hochfeste durchhaertende Staehle unterliegen in der Regel hohen Verschleissbeanspruchungen und werden darueber hinaus oftmals zusaetzlich schwingend beansprucht. Fuer die schwingende ...
1998-12-01
An FEL design for gamma-gamma colliders based on chirped pulse amplification techniques
International Nuclear Information System (INIS)
A next generation e"+-e"- linear collider in the TeV range can be converted into a #gamma#-#gamma# collider by converting it to e"--e"- operation and then generating #gamma#-rays via Compton backscattering with optical beams. This provides unique access to some areas of fundamental physics as well as highly desirable redundancy to the collisions. The required optical beam (with a wavelength of about 1 micron) must have very high peak power, (about 1 TW) as well as average power (about 10 kW). To achieve a 1 : 1 conversion from an electron to #gamma#-quantum, each micropulse must contain about one Joule and must be about one picosecond long, the micropulse peak power being about one Terawatt. To match the electron beam pulse structure, a macropulse consists of a sequence of about one hundred micropulses separated by about one nanosecond, and the macropulses am repeated at a rate of about 100 Hz. Thus, the time average power is about 10 kW propose and analyze a ...
1995-08-21
Am/Cm canister temperature evaluation in CIM5
Energy Technology Data Exchange (ETDEWEB)
To facilitate the evaluation of alternate canister designs, 2 canisters were outfitted with thermocouples at elevations of 1/2, 3 1/2, and 6 1/2 inches from the canister bottom. The canisters were fabricated from two inch diameter schedule 10 and two inch diameter schedule 40 stainless steel pipe. Each canister was filled with approximately 2 kilograms of 49 wt percent lanthanide (Ln) loaded 25SrABS glass during 5 inch Cylindrical Induction Melter (CIM5) runs for TTR Tasks 3.03 and 4.03. Melter temperature, total mass of glass poured, and the glass pour rates were almost identical in both runs. The schedule 40 canister has a slightly smaller ID compared to the schedule 10 canister and therefore filled to a level of 9.5 inches compared to 8.0 inches for the schedule 40 canister. The schedule 40 canister had an empty mass of 1906 grams compared to 919 grams for the schedule 10 canister. The schedule 10 canister was found to have a higher maximum surface temperature by about 50--100 C ...
2000-02-17
Alcoa titanium alloy Ti-10V-2Fe-3Al forgings -- Data sheets
International Nuclear Information System (INIS)
Ti-10V-2Fe-3Al is high strength, metastable beta titanium alloy developed by the Timet Division, Titanium Metals Corporation of America for enhanced forgeability and excellent mechanical property combinations, including deep hardening characteristics. Ti-10-2-3 has been the subject of intense thermomechanical processing (TMP) development and reduction to commercial practice for the full range of open die, closed-die and precision forged products utilized in aerospace and other applications. With commercially proven TMP, Ti-10-2-3 forgings provide a range of strength-fracture toughness combinations from 180 Ksi (1,240 MPa) minimum U.T.S. to 140 Ksi (965 MPa) minimum U.T.S with commensurate fracture toughness. With optimal TMP and these strength-toughness combinations, Ti-10-2-3 forgings are found provide superior smooth and notched fatigue properties critical to aerospace applications over incumbent alpha-beta alloys. The alloy retains 80 percent of its room temperature strength at 600 ...
1993-02-21
International Nuclear Information System (INIS)
Ab initio total energy calculations within the framework of density functional theory have been performed for water molecule adsorption on the (0001) surface of double hexagonal packed americium using a full-potential all-electron linearized augmented plane wave plus local orbitals method (FP-L/APW+lo). Subsequent partial dissociation (OH+H) and complete dissociation (H+O+H) of the water molecule have been examined. The completely dissociated H+O+H configuration exhibit the strongest binding with the surface (3.35 eV), followed by partially dissociated species OH+H (2.23 eV), with all molecular H_2O configurations showing weak physisorption (0.366 eV). For molecular adsorptions, the flat lying orientation of the water molecule if found to be more favorable for majority of the cases. In the case of partial dissociation (OH+H), the vertical orientation of OH molecule with O facing the surface adsorbed at a h3 adsorption site and the H atom adsorbed at another neighboring h3 site is found ...
2009-06-01
Acoustic analysis of combustion engines; Die Akustikanalyse von Verbrennungsmotoren
Energy Technology Data Exchange (ETDEWEB)
For millions of people general noise and especially traffic noise are the main sources of environmental pollution. The increasingly stricter noise pollution abatement limiting values laid down by the law call for motor vehicle noise pollution abatement measures. Within the framework of today`s cost- and performance-oriented automobile and engine development developing engineers are required to reduce noise levels. The present state of the art is described and future possibilities of combustion engine structure-borne noise calculation and optimization are discussed from the point of view of K + P Computerunterstuetzte Strukturanalysen GmbH. (orig.) [Deutsch] Laerm allgemein und dabei speziell wiederum der Verkehrslaerm steht fuer Millionen von Menschen an allererster Stelle der persoenlichen Belastung durch die Umwelt. Zur Minderung der Laermbelastung werden vom Gesetzgeber immer schaerfere Grenzwerte vorgeschrieben, die dazu zwingen, Massnahmen zur Geraeuschreduktion ...
1995-04-01
Absence of isoscalar monopole strength in {sup 56}Fe and {sup 58}Ni
Energy Technology Data Exchange (ETDEWEB)
Measurements with 240 MeV {alpha} particle inelastic scattering with excellent peak/background ratios at small scattering angles including 0{degrees} were made on {sup 56}Fe and {sup 58}Ni using the multipole-dipole-multipole spectrometer at Texas A&M University. Beam was delivered to the spectrometer through a beam analysis system having two bends of 88{degrees} and 87{degrees} respectively. A slit placed after the first 88{degrees} bend was used to define the beam. Slits placed after the second bend (87{degrees}) were used to eliminate slit scattered particles. Comparison of the results of a multiple peak fit to the{sup 58}Ni spectra after continuum subtraction to DWBA calculations revealed about 32% of the E0 EWSR and 58% of the E2 EWSR in the peak, in agreement with previous works. Fits to the angular distribution of the continuum for E{sub x} = 25 MeV show that <15% of the E0 EWSR is present in the continuum. Hence 50% of the EO EWSR must lie above ...
1995-10-01
ATP-dependent partitioning of the DNA template into supercoiled domains by Escherichia coli UvrAB
International Nuclear Information System (INIS)
The helicase action of the Escherichia coli UvrAB complex on a covalently closed circular DNA template was monitored using bacterial DNA topoisomerase I, which specifically removes negative supercoils. In the presence of E. coli DNA topoisomerase I and ATP, the UvrAB complex gradually introduced positive supercoils into the input relaxed plasmid DNA template. Positive supercoils were not produced when E. coli DNA topoisomerase I was replaced by eukaryotic DNA topoisomerase I or when both E. coli and eukaryotic DNA topoisomerases I were added simultaneously. These results suggest that like other DNA helix-tracking processes, the ATP-dependent action of the UvrAM complex on duplex DNA simultaneously generates both positive and negative supercoils, which are not constrained by protein binding but are torsionally strained. The supercoiling activity of UvrAB on UV-damaged DNA was also studied using UV-damaged plasmid DNA and a mutant UvrA protein that lacks the 40 ...
A study of neutron room scattering at RPCF
International Nuclear Information System (INIS)
High energy physics facilities must monitor the radiation doses received by their personnel. This monitoring can only be effective if the radiation detection devices can be calibrated with a good degree of accuracy. Radiation fields are usually composed of several types of radiation, including gamma rays, beta radiation, neutrons, etc. The neutron detection instruments respond not only to the neutrons coming directly from the source but also those scattered from the floor, walls, and ceiling. The amount of neutron scattering varies from site to site depending on the construction materials and layout of the building. The purpose of this study was to determine the scattered neutron fraction in the central volume of the calibration mezzanine of the Radiation Physics Calibration Facility (RPCF) at the Fermi National Accelerator Laboratory (Fermilab). At Fermilab, radiation workers dosimeters use CR39 for neutron detection, which are sent to an outside vendor for reading. As part of the ...
1997-01-05
A study of neutron room scattering at RPCF
Energy Technology Data Exchange (ETDEWEB)
High energy physics facilities must monitor the radiation doses received by their personnel. This monitoring can only be effective if the radiation detection devices can be calibrated with a good degree of accuracy. Radiation fields are usually composed of several types of radiation, including gamma rays, beta radiation, neutrons, etc. The neutron detection instruments respond not only to the neutrons coming directly from the source but also those scattered from the floor, walls, and ceiling. The amount of neutron scattering varies from site to site depending on the construction materials and layout of the building. The purpose of this study was to determine the scattered neutron fraction in the central volume of the calibration mezzanine of the Radiation Physics Calibration Facility (RPCF) at the Fermi National Accelerator Laboratory (Fermilab). At Fermilab, radiation workers dosimeters use CR39 for neutron detection, which are sent to an outside vendor for reading. As part of the ...
1996-09-01
Thermomechanical fatigue of ODS superalloys; Thermomechanische Ermuedung von ODS-Superlegierungen
Energy Technology Data Exchange (ETDEWEB)
The ODS superalloys MA 6000 and MA 760 were investigated with regard to their behaviour under non-isothermal fatigue stress. For this purpose, strain-controlled thermomechanical and bithermal experiments with different phase relationships between strain and temperature were carried out on the one hand; on the other hand, the deformation behaviour under thermomechanical stress was modelled on the basis of isothermal cyclic creep data. The fatigue experiments show that a diamond-shaped cycle derived from the stress pattern of a turbine blade is clearly less critical than in-phase and out-of-phase cycles. The life of the diamond-shaped cycle is determined by oxidation-induced crack initiation and propagation and can be predicted easily with a suitable damage model. Important damage parameters required by the model can be obtained by the less complicated bithermal fatigue tests. Modelling of the TMF hystereses suggests that cyclic, non-isothermal deformaltion is determined mainly by ...
1995-07-01
Energy Technology Data Exchange (ETDEWEB)
The high-speed direct-injection diesel engine for passenger cars has been a resounding success in the marketplace in the last few years. This was due to an intensive development process as a result of which the direct-injection diesel engine for passenger cars is currently setting new standards with regard to performance and fuel consumption in spite of the constant tightening of emission regulations. Of particular importance in this context is exhaust gas recirculation (EGR). This technology permits a considerable reduction in nitrogen oxide emissions, which are especially critical in the case of the direct-injection diesel engine. In addition, continuing development of supercharging technology, in particular the turbocharger with variable turbine geometry, have allowed further improvement of the full-load behaviour and the engine response and a considerable reduction in the fuel consumption of direct-injection diesel engines. This FVV paper deals with the fundamentals of the ...
1999-03-01
Energy Technology Data Exchange (ETDEWEB)
A singular stress field can occur at the edge of the joint plane in a thermally or mechanically loaded material compound. This stress field was calculated analytically and was compared with the results from the finite element method. If one of the two partners consists of ceramic material, unstable crack spread starting from faults in this strongly stressed area can lead to failure. In linear elastic material, the behaviour of a crack is clearly described by the stress intensity factors. These can be calculated for a known stress distribution in the uncracked structure by the method of the weight function. The corresponding weight functions for surface cracks parallel to the boundary surface were determined with the aid of suitable reference load cases. The effect of the position of the crack in the compound and the elastic constants of the compound are discussed. For examples, the stress intensity factors for cracks in a thermally stressed material compound were determined by the ...
1995-03-01
Energy Technology Data Exchange (ETDEWEB)
The first working meeting of the SAPIERR project about regional final storage of radioactive waste in the European Union was held in Piestany, Slovak Republic, on February 19 and 20, 2004. SAPIERR stands for Support Action: Pilot Initiative for European Regional Repositories. This is an independent study supported financially by the European Union within the 6th Research Framework Program. The background to the project is the debate about the feasibility of regional repositories for radioactive waste in the European Union, which has come up again especially with a view to the new accession countries and the draft of a waste management directive within the framework of the Nuclear Package. The results of the SAPIERR Project will be presented in Brussels at a concluding international seminar, most probably in October 2005. The seminar will be open not only to the participating countries but also to other interested European and non-European states. (orig.) [German] ...
2004-06-01
Energy Technology Data Exchange (ETDEWEB)
A prospective study was performed on 50 patients suffering from osteochondritis dissecans of the knee and ankle to define criteria for stability and fixation of osteochondral lesions. Morphological parameters in MRI (size, fragmentation, cartilage, interface) and conventional radiology (separation, fragmentation) were registered and compared with arthroscopical staging. MRI staging based on different types of interfaces was demonstrated on T{sub 1}- and T{sub 2}-weighted images. MRI could correctly predict a Grade 1 lesion in 50%, a Grade 2 lesion in 90%, a Grade 3 lesion on 0%, and a Grade 4 lesion in 79%. Stable lesions were differentiated from unstable lesions in 90%. Radiographic findings corresponded with arthroscopic staging in only 56% of the cases because fibrotic connection may guarantee stability in case of bony separation. (orig./MG) [Deutsch] In einer prospektiven Studie an 50 Patienten mit einer Osteochondrosis dissecans (OD) des Knie- und Sprunggelenkes sollten ...
1995-07-01
Energy Technology Data Exchange (ETDEWEB)
To study the biogeochemical behaviour, mobility and transport of trace metals in seawater (Se, Mo, Cd, Pb, Hg, Cu, Co, Fe, Ni, Zn), in suspended particulate matter (Mo, Cd, Pb, Cu, Co, Fe, Ni, Zn, Al, Mn) and in sediments of the inner and outer coastal regions, samples were collected on 3 separate cruises during a one year period (Mai 1993 - April 1994) at 20 stations in the coastal area of Mecklenburg-Vorpommern. Standard hydrographic parameters, nutrients and dissolved oxygen were also measured. Priority was taken to establish the methods for the determination of molybdenum and selenium. To study the behaviour of these two elements in detail, longterm measurements were carried out weekly between January 1993 and June 1994 at the `Messsteg/Warnemuende`. Because of parallel measurements correlations to biological, chemical and hydrographic parameters have been tested. The total database is summarized in the Appendix. The results are presented in 30 figures and 13 tables and are ...
1995-04-01
One of the NASA research activities was to identify, characterize, and simulate a series of technologies that could be used for hydrogen production at NASA Kennedy Space Center (KSC) using locally available sources. This project examined the production of hydrogen from solar energy. To produce hydrogen by water splitting, the operating voltage of conventional photovoltaic (PV) cells cannot supply the overvoltage required. Thus, the objective of this project was to research and develop photoelectrochemical (PEC) cells that can supply the required voltage for water splitting by constructing a multiple bandgap tandem PV cell and a photocatalyst that can be activated by infrared (IR) photons transmitted through the PV cell. The proposed concept is different from conventional PEC water splitting by using multiple band gap combinations. The advantages for this PEC cell concept is that the PV cells are not in contact with the electrolyte solution, thus reducing the problems of corrosion and ...
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
Lung cancer staging according to the TNM system is based on morphological assessment of the primary cancer, lymph nodes and metastases. All aspects of this important oncological classification are measurable with MRI. Pulmonary nodules can be detected at the clinically relevant size of 4-5 mm in diameter. The extent of mediastinal, hilar and supraclavicular lymph node affection can be assessed at the same time. The predominant metastatic spread to the adrenal glands and spine can be detected in coronal orientation during dedicated MRI of the lungs. Search focused whole body MRI completes the staging. Various additional MR imaging techniques provide further functional and clinically relevant information during a single examination. In the oncological context the most important techniques are imaging of perfusion and tumor motion. Functional MRI of the lungs complements the pure staging and improves surgical approaches and radiotherapy planning. (orig.) [German] Das Staging des ...
2010-08-15
Neutron cross-sections on minor actinides for next generation reactors: new data from n_TOF (CERN)
International Nuclear Information System (INIS)
Full text: Climatic problems associated to the greenhouse effect have recently stimulated a renewed interest in nuclear energy production, and triggered new studies aimed at developing future generation systems that would address current major safety, proliferation and waste concerns. In particular a possible solution to the waste problem could come from transmutation of the highly radiotoxic nuclear waste in Accelerator Driven Systems or in Generation-IV fast nuclear reactors. The design and operation of the new systems require accurate cross-section data on a large number of isotopes, in particular plutonium, minor actinides, long-lived fission fragments and structural materials. An important contribution to the field is being provided since a few years by a new time of-flight facility operative at CERN, n_TOF. The main features of the neutron beam, in particular the wide energy spectrum, ranging from thermal energy to hundreds of MeV, the very high instantaneous neutron flux, low ...
2008-06-01
Energy Technology Data Exchange (ETDEWEB)
1. Cyanide degradation: Of the cyanide- and thiocyanate-degrading bacteria, Burkholderia cepacia and Pseudomonas spec. were the most effective. 2. Biosorption: Of the isolates suited for biosorption of heavy metals, 597-A (non-identifiable) and 597-A2 (Aspergillus fumigatis) had the biggest potential. The sorption capacity of the fungi for metals varied with the C source used for their growth: apple juice > molasses > glucose. The fungi are not cyanide-sensitive and can even degrade cyanide. Living biomass had better metal sorption efficiencies than dead mycelium. The biosorption rates in waste water were usually higher than in broth. Depending on the metal composition and concentrations and on the exposure time and volume of the mycelia, up to 85 % of the initial concentration was removed from the liquid phase. The capacity of different biomasses for the sorption of metal mixtures was between 65 and 80 mg/g of dry matter depending on the experimental conditions, with ...
1999-12-01
Energy Technology Data Exchange (ETDEWEB)
The nuclear structure of A {proportional_to} 100 nuclei has been studied in the frame of this thesis with a recently developed {beta} - {gamma} - {gamma} triple coincidence fast timing technique and different models such as shell model, hydrodynamic model, Nilsson and particle-rotor models. This technique which allows the measurement of the level lifetimes in the ps range has been applied at JOSEF at the research reactor DIDO of KFA Juelich in studes of the short-lived neutron-rich nuclei in the A {approx_equal} 100 region. Lifetimes of level in {sup 96},{sup 98},{sup 100} ZR, {sup 99},{sup 101}-{sup 104} Nb, {sup 100}-{sup 105} Mo have been measured, which are in many cases completely new, and otherwise more precise than previously published data. From the lifetimes of the members of rotational bands, the size of the nuclear deformations has been deduced. (orig./HSI). [Deutsch] Im Rahmen dieser Doktorarbeit wurde die Kernstruktur der A {proportional_to} 100 Kerne untersucht. Dazu ...
1992-08-01
Energy Technology Data Exchange (ETDEWEB)
Southeastern Finland belongs to the area covered by the Weichselian ice sheet, where the release of the ice load caused a rapid isostatic rebound during the postglacial time. While the mean overall apparent uplift is of the order of 2 mm/yr today, in the early Holocene time it was several times higher. A marked decrease in the rebound rate occurred around 8500 BP, however, since then the uplift rate has remained high until today, with a slightly decreasing trend towards the present time. According to current understanding there have neither been temporary increases nor decreases in the rate of uplift during the postglacial time. Even so, it is not known for sure whether there are regional irregularities on the rebound in Finland. Concurrently with land uplift, relative sea-level changes in the Baltic basin were also strongly affected by the global eustatic rise of sea-level. During the early Litorina Sea stage on the southern coast of Finland around 7000 BP, the rise in sea-level ...
1999-09-01
Energy Technology Data Exchange (ETDEWEB)
FLUTAN is a highly vectorized computer code for 3-D fluiddynamic and thermal-hydraulic analyses in cartesian and cylinder coordinates. It is related to the family of COMMIX codes originally developed at Argonne National Laboratory, USA. To a large extent, FLUTAN relies on basic concepts and structures imported from COMMIX-1B and COMMIX-2 which were made available to KfK in the frame of cooperation contracts in the fast reactor safety field. While on the one hand not all features of the original COMMIX versions have been implemented in FLUTAN, the code on the other hand includes some essential innovative options like CRESOR solution algorithm, general 3-dimensional rebalacing scheme for solving the pressure equation, and LECUSSO-QUICK-FRAM techniques suitable for reducing `numerical diffusion` in both the enthalphy and momentum equations. This report provides users with detailed input instructions, presents formulations of the various model options, and explains by means of ...
1991-05-01
FLUTAN 2.0. Input specifications
Energy Technology Data Exchange (ETDEWEB)
FLUTAN is a highly vectorized computer code for 3D fluiddynamic and thermal-hydraulic analyses in Cartesian or cylinder coordinates. It is related to the family of COMMIX codes originally developed at Argonne National Laboratory, USA, and particularly to COMMIX-1A and COMMIX-1B, which were made available to FZK in the frame of cooperation contracts within the fast reactor safety field. FLUTAN 2.0 is an improved version of the FLUTAN code released in 1992. It offers some additional innovations, e.g. the QUICK-LECUSSO-FRAM techniques for reducing numerical diffusion in the k-{epsilon} turbulence model equations; a higher sophisticated wall model for specifying a mass flow outside the surface walls together with its flow path and its associated inlet and outlet flow temperatures; and a revised and upgraded pressure boundary condition to fully include the outlet cells in the solution process of the conservation equations. Last but not least, a so-called visualization option based on VISART ...
1996-05-01
Elk and Deer Study, Material Disposal Area G, Technical Area 54: Source document
Energy Technology Data Exchange (ETDEWEB)
As nuclear research has become more prevalent, environmental contamination from the disposal of radioactive waste has become a prominent issue. At Los Alamos National Laboratory (LANL) in northern New Mexico, radioactive contamination from disposal operations has raised some very specific concerns. Material Disposal Area G (Area G) is the primary low-level radioactive waste disposal site at LANL and occupies an area adjacent to land belonging to the Native American community of the Pueblo of San Ildefonso. Analyses of soil and vegetation collected from the perimeter of Area G have shown concentrations of radionuclides greater than background concentrations established for northern New Mexico. As a result, Pueblo residents had become concerned that contaminants from Area G could enter tribal lands through various ecological pathways. The residents specifically questioned the safety of consuming meat from elk and deer that forage near Area G and then migrate onto tribal lands. ...
1999-09-01
Energy Technology Data Exchange (ETDEWEB)
We performed a comparative study of digitally and conventionally acquired images in gastrointestinal examinations. Radiation dose and spatial resolution were determined in a water phantom. In 676 examinations with either conventional or digital imaging (system: Diagnost 76, DSI) the number of images and the duration of the fluoroscopy time were compared. 101 examinations with digital as well as conventional documentation were evaluated by using 5 criteria describing the diagnostic performance. The entrance dose of the DSI is 12% to 36% of the film/screen system and the spatial resolution of the DSI may be better than that of a film/screen system with a speed of 200. The fluoroscopy time shows no significant difference between DSI and the film/screen technique. In 2 of 4 examination modes significantly more images were produced by the DSI. With exception of the criterion of edge sharpness, DSI yields a significantly inferior assessment compared with the film/screen technique. (orig./MG) ...
1995-10-01
Creep-microcrack growth in alloy 800 HT at elevated temperatures
Energy Technology Data Exchange (ETDEWEB)
The aim of the presented investigation was to gain information about the behaviour of the initiation and growth of intercrystalline creep cracks during creep deformation from the evaluation of metallographic micrographs. The austenitic steel X10 NiCrAlTi 32 20 HT (Alloy 800 HT) was investigated by carrying out creep tests at 800 and 900 C with different nominal stresses until fracture. Additional tests are carried out on certain creep strains in the late tertiary creep stage. The creep tests are followed by a metallographic investigation of the crept specimens. The statistical distribution of the microcrack lengths was used to estimate the rate of crack initiation and crack growth. It is found that the rate of growth of the intercrystalline creep cracks in Alloy 800 HT is dependent on the applied stress and the creep strain reached. The rate of growth of long cracks was only slightly higher than that of short cracks and was lower than predictions based on fracture mechanics concepts. ...
1997-05-01
International Nuclear Information System (INIS)
Doping of manganese (Mn3+/Mn4+) into the Aurivillius phase Pb1-xBi4+xTi4-xMnxO15 was carried out using the molten salt technique for various Mn concentrations (x=0, 0.2, 0.4, 0.6, 0.8, and 1). Single phase samples could be obtained in the composition range with x up to 0.6 as confirmed by X-ray and neutron diffraction analysis. Dielectric measurements show a peak at 801, 803, 813 and 850 K for samples with x=0, 0.2, 0.4, and 0.6, respectively, related to the ferroelectric transition temperature (Tc). The main contribution of the in-plane polarization for x?0.2 which was calculated from the atomic positions obtained by the structure analysis is the dipole moment in the Ti(1)O6 layer; however, for x?0.4 the polarization originates from the dipole moment in the Ti(2)O6 layer. Mn doping in the Pb1-xBi4+xTi4-xMnxO15 does not show any long range magnetic ordering. -- Graphical abstract: The dipole moment of TiO6 dependence of x in Pb1-xBi4+xTi4-xMnxO15 (0?x?0.6): (a) along a-axis and (b) on ...
2011-05-01
Energy Technology Data Exchange (ETDEWEB)
Storing electrical energy in batteries is not a viable option for sustaining a country's energy economy. The mass and volume, as well as the costs, of electrochemical components required for this would be beyond all reason. Nevertheless, in certain applications the storage of electrical energy does have significant advantages over other technologies. For example, electrically powered road vehicles emit no exhaust fumes and very little noise at their place of operation. In this way they contribute substantially to air and noise pollution control in urban areas. Photovoltaic applications permit environmentally friendly electricity applications in places remote from the public grid where conventional solutions are prohibitively expensive. More than in the past, battery systems today have to meet a wide range of technical, economic and ecological requirements in order to be marketable. This is why the ''Zoxy'' zinc-air battery system was ...
1997-02-01
ZZ DECAYREM/C, Decay Spectra Library for EXREM Calculation
International Nuclear Information System (INIS)
Description of problem or function: Format: EXREM III; Nuclides: radioactive decay data on 252 Nuclides: 1H-3, 4Be-7, 6C-11, 6C-14, 7N-13, 8O-15, 9F-18, 11Na-22, 11Na-24, 12Mg-28, 13Al-28, 15P-32, 15P-33, 16S-35, 17Cl-36, 17Cl-38, 18A-37, 18A-39, 19K-40, 19K-42, 19K-43, 20Ca-45, 20Ca-47, 20Ca-49, 21Sc-46, 21Sc-47, 21Sc-49, 24Cr-51, 25Mn-52M, 25Mn-52, 25Mn-54, 26Fe-52, 26Fe-55, 26Fe-59, 27Co-56, 27Co-57, 27Co-58, 27Co-60, 28Ni-56, 28Ni-63, 29Cu-64, 30Zn-65, 30Zn-69M, 30Zn-69, 31Ga-67, 31Ga-68, 32Ge-77, 33As-76, 33As-77, 34Se-75, 35Br-80M, 35Br-80, 35Br-82, 35Br-83, 35Br-84, 36Kr-79, 36Kr-83M, 36Kr-85M, 36Kr-85, 36Kr-87, 36Kr-88, 37Rb-84, 37Rb-86, 37Rb-87, 37Rb-88, 37Rb-89, 37Rb-90M, 37Rb-90, 38Sr-85, 38Sr-87M, 38Sr-89, 38Sr-90, 38Sr-91, 38Sr-92, 38Sr-93, 39Y-87, 39Y-88, 39Y-90, 39Y-91M, 39Y-91, 39Y-92, 39Y-93, 40Zr-93, 41Nb-93M, 40Zr-95, 40Zr-97, 41Nb-95M, 41Nb-95, 41Nb-97M, 41Nb-97, 42Mo-99, 43Tc-99M, 43Tc-99, 44Ru-103, 44Ru-105, 44Ru-106, 45Rh-103M, 45Rh-105M, 45Rh-105, 45Rh-106, ...
Energy Technology Data Exchange (ETDEWEB)
Purpose: The nint version of the licensing regulation for medical doctors (Approbation Regulation (AR)) sets a benchmark in terms of practical experience, interdigitation of preclinical and clinical studies, interdisciplinary approach, economic efficiency, independence of students, added new teaching and learning modalities, and ongoing evaluation of the progress of the medical students. It is the aim to implement these major points of the AR in a model course for diagnostic radiology and radiation protection within the scope of the Virtual University of Bavaria and test them in practice. Materials and Methods: In cooperation with residents and board certified radiologists, students developed the virtual course 'Web-Based Training (WBT) Radiology' in diagnostic radiology and radiation protection for students in the first clinical semester. A representative target group taken from the student body was asked about the options to get access to the World Wide Web ...
2004-06-01
Energy Technology Data Exchange (ETDEWEB)
The staging of patients with multiple myeloma demands sensitive imaging methods for the assessment of the skeletal system. MRI allows for direct visualization of the bone marrow which exhibits five different infiltration patterns in multiple myeloma: 1. normal appearance of the bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. ''salt and pepper'' pattern with inhomogeneous bone marrow signals due to multiple fat islands. The combination of T1w-SE and STIR sequences is best suited for detecting all infiltration patterns and for the differential diagnoses e. g. hemangiomas. With parallel imaging in MRI, acquisition times can be markedly reduced and whole-body screening of the bone marrow can be achieved within 30 min. MRI is superior to radiography for the detection of focal as well as diffuse infiltration. Multidetector computed tomography and especially 16- and 64-detector row ...
2004-09-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: An animal model is used to investigate whether MR angiography combined with super-paramagnetic particles of iron oxide (SPIO) is suitable for detecting thromboses. Methods: 42 rats in groups of 7 each were examined on days 1, 3, 5, 7, 9 and 11, respectively, after mechanical/chemical thrombus induction in a 1.5 Tesla magnet with a FISP sequence (TR/TE/FA 50 ms/6 ms/40 ). Imaging was performed before and up to 90 minutes after intravenous injection of 30 {mu}mol FE/kg BW of the experimental SPIO (hydrodynamic diameter, 34{+-}17 nm LLS; R1 and R2 relaxivity at 0.47 T, 31 and 57 L/(mmol*s)). MIP reconstructions of MR angiographies were submitted to consensus assessment by two examiners using histology as the gold standard. Results: The image quality of MIP reconstructions was rated as good in 38 of 42 cases. With regard to thrombotic vessel occlusion, MR angiography coincided with histology in 17 of 42 cases and differed in 25, lumen narrowing being overestimated by MRI in 4 ...
1999-03-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: The purpose of this study was to observe the process of fixation in liver specimens non-invasively by means of magnetic resonance. The fixation process of several formaldehyde-containing solutions was monitored with MRI and MRS at two different temperatures. Materials and Methods: Liver specimens were conserved in aqueous fixative solutions containing formaldehyde concentrations of 0.7, 1.8, 4 and 7.2% and at different temperatures of 5 C and 20 C. MRI was performed with T1-, T2- and PD-weighted TSE sequences, a 2D FLASH-sequence with and without magnetization transfer, and a FISP 3D-sequence on a clinical 1.5 Tesla MR whole-body unit, and MRS with {sup 1}H-spectroscopic methods (STEAM-sequence) on a 3 Tesla MR whole-body unit. Results: The diffusion of formaldehyde into the tissue was best identified on PD- and T1-weighted images as a band under the liver surface with increasing thickness, penetrating especially fast during the first three days. Spectroscopic measurements ...
2004-04-01
Energy Technology Data Exchange (ETDEWEB)
From autumn this year, the FRJ-2 of the Research Center Juelich will be supplying molybdenum targets to the Institut National des Radioelements in Fleurus, Belgium - which deals in medical radio-isotopes worldwide - thus helping to meet the need for technetium-99, which is used in the medical profession for diagnostic purposes because of its favourable radiological characteristics. Technetium-99 is formed as a result of the radioactive decay of molybdenum-99. For many years now, molybdenum has been produced by the irradiation of uranium in research reactors, so that the initiation of molybdenum production in the FRJ-2 is not especially new. What is unusual, however, are the particular peripheral conditions which result from the combination of the irradiation requirements, a predetermined target design and the technical characteristics of the reactor and which necessitated special solutions. This applies especially to the handling of the targets after irradiation, which is much more ...
1999-06-01
Model to simulate the interaction between boron carbide and steam or air at high temperature
Energy Technology Data Exchange (ETDEWEB)
The oxidation of boron carbide in steam or air was recently extensively studied especially in Forschungszentrum Karlsruhe, Institut fuer Materialforschung. An important data set is available for the interaction modelling. An oxygen diffusion model through the superficial liquid boron oxide formed on the boron carbide external surface associated to a superficial reaction between the liquid boron oxide and steam is proposed to simulate the experimental kinetics from BOX rig and thermogravimetric tests on the interaction between steam and boron carbide at a temperature range 800 C to 1400 C. The oxygen diffusion model will be also useful to simulate interaction between boron carbide and Ar+O2 (air simulation) atmosphere when the steam pressure becomes zero. From the analysis of BOX rig experimental kinetics of non-condensable (H2, CO2, CO and CH4) gases we propose an oxygen diffusion model through the liquid boron oxide and a ''steam/liquid boron ...
2005-03-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: To determine the value of MRI in the preoperative evaluation of chronic paranasal sinusitis and to compare the results with CT and intraoperative findings. Method/Materials: 42 patients with clinical signs of chronic paranasal sinusitis underwent MRI after CT evaluation on one day, with subsequent functional endoscopic sinus surgery on the next day. Coronary CT was obtained with 5-mm slices and table-feed in the prone position, while MRI was performed in the supine position with coronary T{sub 2}-TSE+pd and coronary and transverse HASTE, each with 5-mm slice thickness. Aquisition time in MRI was less than 8 minutes. Two radiologists reviewed the CT and MRI scans for signs of sinusitis and detection of anatomical landmarks. The results were correlated with the intraoperative findings. Results: MRI offered no artifacts of dental work and showed more often high quality pictures than CT. CT and MRI demonstrated a good correlation in the detection of mucosal pathologies ...
2001-04-01
Energy Technology Data Exchange (ETDEWEB)
To evaluate the usefulness of radiation therapy alternative to surgery for clinical N0-N1 non-small cell lung cancer (NSCLC). From 1976 through 1989, 116 patients with NSCLC without mediastinal involvement were treated with definitive radiation therapy alone at Gunma University Hospital. All patients were treated with once-daily standard fractionation using 10 MV X-rays. The total dose ranged from 60 Gy to 80 Gy. The actuarial 2- and 5-year survival rates of the entire group were 43% and 20%, respectively with a median survival time of 19 months. The survival of 76 patients with stage T2 tumors was significantly better than that of 28 patients with T3 tumors (mean survival time 21 versus 15.5 months; p<0.05). Sixty-two patients with tumors less than 5 cm in diameter had a 2-year progression rate of 20%, in comparison with 39% of 54 patients with tumors greater than 5 cm. The difference of survivals for these 2 groups was statistically significant. Twelve patients given a total dose ...
1996-09-01
Energy Technology Data Exchange (ETDEWEB)
The further optimisation and improvement of the efficiency of internal combustion engines require the realisation of new technologies leading to a distinctively faster warm-up behaviour of the coolant and lubricants as well as of the engine components after a cold start. In order to achieve reduced fuel consumption and exhaust gas emissions with the help of heat management, the design criteria of innovative cooling systems need to be reflected and adapted to future requirements. The use of intelligent components within the cooling system, such as the 'Stand Alone Rotary Valve' as a thermostat's substitute or the use of coolant pumps with a rotary valve integrated into the pump's inlet chamber, offer new ways to realise in a decisively quicker and more flexible way the appropriate heating up and cooling down procedures at varying driving conditions. A description of both of the intelligent components for the cooling system is given in this paper. The ...
2001-07-01
Differential diagnosis of rheumatic diseases; Differenzialdiagnose rheumatischer Erkrankungen
Energy Technology Data Exchange (ETDEWEB)
Which imaging modalities are appropriate for the Differential diagnosis of Rheumatic diseases. MRI has far most the highest sensitivity and is unequaled in its brilliant presentation of Anatomy and Pathology. But it is sometimes forgotten, that this is at least in part the result of carefully selected sequences, dedicated to the expected result. In a method totally independent of any result, this should not be the case. In contrary this method should be highly standardised and regardless what will be the findings. This is true for Plain X-ray. It will be shown, that already the outer silhouette of the soft parts with different features of swelling, and differences in density and even more - defects or appositions of the bony silhouette in the majority of cases at least will allow to classify the patient for a group of diseases and in many cases will lead to a definite diagnosis. Differential diagnoses like Rheumatoid Arthritis versus Psoriatic Arthritis or simply but not always simple ...
2006-05-15
Diagnosis of plasmocytomas using magnetic resonance imaging; Diagnostik des Plasmozytoms mit der MRT
Energy Technology Data Exchange (ETDEWEB)
Background. In multiple myeloma 5 different infiltration patterns can be differentiated: 1. Normal appearance of bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. 'salt-and pepper' pattern with inhomogeneous bone marrow with interposition of fat islands. Methods. For the fast and total acquisition of all patterns a combination of a T1-weighted spin echo sequence and a fat suppression technique is superior. The focal involvement is clearly demonstrated as areas of high signal intensity on e.g. STIR images. Diffuse involvement can be quantified objectively by calculation of the percentage of signal intensity increase after contrast material injection. MRI is superior to X-ray in focal and diffuse involvement. With ultrafast sequences a 'screening' of the whole red bone marrow as for myeloma infiltration is possible. Prognosis. In prognosis studies diffuse infiltration is inferior to ...
2000-08-01
DWPF Recycle Evaporator Shielded Cells Testing
Testing was performed to determine the feasibility and processing characteristics of evaporation of actual Defense Waste Processing Facility (DWPF) recycle material. Samples of the Off Gas Condensate Tank (OGCT) and Slurry Mix Evaporator Condensate Tank (SMECT) were transferred from DWPF to the Savannah River National Lab (SRNL) Shielded Cells and blended with De-Ionized (DI) water and a small amount of Slurry Mix Evaporator (SME) product. A total of 3000 mL of this feed was concentrated to approximately 90 mL during a semi-batch evaporation test of approximately 17 hours. One interruption occurred during the run when the feed tube developed a split and was replaced. Samples of the resulting condensate and concentrate were collected and analyzed. The resulting analysis of the condensate was compared to the Waste Acceptance Criteria (WAC) limits for the F/H Effluent Treatment Plant (ETP). Results from the test were compared to previous testing using simulants and OLI modeling. ...
2005-07-01
A new concept for covered stent protected carotid angioplasty: an ex vivo study
Energy Technology Data Exchange (ETDEWEB)
Objective: To determine the efficacy of a covered stent prototype designed for protected carotid angioplasty to reduce cerebral embolization. Material and Method: The covered stent tested is made of nitinol, coated with a polyurethane membrane (MembraX{sup TM}; porous size 80 {mu}m). In a bench-top model (flow-rate 650 ml/min, pulsatile flow [dicrote] 123 Pulses/min, pressure 100/60 mm Hg [mean pressure 80 mmHg]) with inserted human carotid (n=6) stent implantation was performed (8/32 mm). Passed particles (mg) were determined in the effluent of a 100 {mu}m filter prior to intervention, after stent deployment and after final dilation (5 mm). Results: When stenting carotid arteries obtained from human cadavers, the highest rate of particle embolization was measured while crossing the lesion with the delivery device (6,8 mg; for all p<0,05), embolization after additional balloon angioplasty and particle rates measured in the effluent filter prior covered stent placement were ...
2003-12-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and separately read by ...
2002-10-01
Energy Technology Data Exchange (ETDEWEB)
As part of the demonstration testing of the Purge Water Management System (PWMS) technology at the Savannah River Site (SRS), four wells were equipped with PWMS units in 1997 and a series of sampling events were conducted at each during 1997-1998. Three of the wells were located in A/M Area while the fourth was located at the Old Radioactive Waste Burial Ground in the General Separations Area.The PWMS is a ''closed-loop'', non-contact, system used to collect and return purge water to the originating aquifer after a sampling event without having significantly altered the water quality. One of the primary concerns as to its applicability at SRS, and elsewhere, is whether the PWMS might resample groundwater that is returned to the aquifer during the previous sampling event. The purpose of the present investigation was to compare groundwater chemical analysis data collected at the four test wells using the PWMS vs. historical data ...
1999-04-27
Energy Technology Data Exchange (ETDEWEB)
Introduction: The goal of this study was to compare contrast-enhanced T1-weighted Flash and Turbo-Flash sequences with conventional spin-echo sequences as a basis for planning high-precision radiotherapy. Methods: A total of 25 consecutive patients with different intracranial tumors and a disrupted blood-brain barrier were studied. T1-weighted Flash, Turbo-Flash and conventional spin-echo images were evaluated after controlled 30-s infusion of 0.1 mmol/kg body weight of Gd-DTPA. The evaluation of the three sequences included the measurement of the signal- and contrast-to-noise ratios, the visual inspection of the tumors and artifacts, and the measurement of tumor size. Results: The signal- and contrast-to-noise ratios were significantly (P<0.05-0.01) lower for Flash and Turbo-Flash than for conventional spin-echo sequences. However, visual inspection of the contrast-enhancing tumors revealed in 23 and 24 of 25 lesions of Flash and Turbo-Flash images, respectively, good or very good ...
1997-03-01
Energy Technology Data Exchange (ETDEWEB)
We report for the first time about a micromachined mass flow sensor directly integrated between the double guidance and the needle seat into the body of a Common Rail (CR) injection nozzle. The thermal measurement principle was chosen because gaseous as well as liquid mass flows can be determined fast and precisely. Additionally, with glass-ceramic materials fabricated in a low cost batch process, a high temperature and especially pressure stable substrate can be used. The flow sensitive thin film is realized by an e-beam evaporated 110 nm thick molybdenum (Mo) layer. The latter is electrically characterized by the resistivity of {rho} = 8.2 x 10{sup -7} {omega} m ({+-}2%) at room temperature as well as by the first {alpha}=4.5 x 10{sup -4} K{sup -1} ({+-}5%) and second {beta}=3.0 x 10{sup -6} K{sup -2} ({+-}12%) temperature coefficients of resistance up to 300 C. The static temperature field at and around the thin film sensor on the glass-ceramic substrate is investigated with an IR ...
2001-05-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: Measurement of the oscillating CSF flow in the spinal canal (SC) of healthy volunteers and in patients with post-traumatic syringomyelia (PTS) using an optimized MRI protocol as well as to determine whether stenosis induced velocity changes are detectable using MRI. Methods: In 68 healthy volunteers quantitative studies of CSF flow in the cervical, thoracic, and lumbar regions were performed. First, an optimized sequence was developed and tested in 19 volunteers using four different flow-encoding velocities (4, 8, 12, 16 cm/s). Secondly, the optimized sequence was employed in 49 volunteers to measure the different CSF patterns in the cervical, thoracic, and lumbar spinal canals (CSC, TSC, LSC). Part three of the study, in which patients with PTS are being examined is still underway. We measured the maximum velocity (cm/s), the pixel area (mm{sup 2}), and the stroke volume (ml/s). Using a flow model the velocities prior to and after compression with 5 different power levels ...
2001-04-01
Energy Technology Data Exchange (ETDEWEB)
Low energy buildings promise significant energy savings and help climate preservation by cutting down on annual heating requirements to values below 70 kWh per m{sup 2} dwelling space. It is expected that low energy constructions will become the common standard by the year 2000 as a result of the forthcoming energy saving ordinance. For making the introduction and implementation of this standard successful, practical experience will be essential. For this reason, the state government of Hesse has supported respective pilot projects 1987. In 1989 the funding programme `30 low energy buildings in Hesse` has been established. Consecutively - between 1989 and 1993 - 29 buildings were erected. At first, the thermal quality of the crafted building construction including the ventilation systems was checked. Consecutively, energy consumption, indoor and outdoor temperatures were measured over a time span of several years. The experience of the inhabitants was surveyed. The `Institut Wohnen und ...
1998-10-01
Final Scientific EFNUDAT Workshop
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40th Anniversary of the First Proton-Proton Collisions in the CERN Intersecting Storage Rings (ISR)
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