Enhanced separation of rare earth elements

Energy Technology Data Exchange (ETDEWEB)

Lyon, K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Herbst, R. S. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, T. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Welty, A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Soderstrom, M. D. [Cytec Solvay Group, Tempe, AZ (United States); Jakovljevic, B. [Cytec Solvay Group, Niagara Falls, ON (Canada)

2016-09-01

Industrial rare earth separation processes utilize PC88A, a phosphonic acid ligand, for solvent extraction separations. The separation factors of the individual rare earths, the equipment requirements, and chemical usage for these flowsheets are well characterized. Alternative ligands such as Cyanex® 572 and the associated flowsheets are being investigated at the pilot scale level to determine if significant improvements to the current separation processes can be realized. These improvements are identified as higher separation factors, reduced stage requirements, or reduced chemical consumption. Any of these improvements can significantly affect the costs associated with these challenging separation proccesses. A mid/heavy rare earth element (REE) separations flowsheet was developed and tested for each ligand in a 30 stage mixer-settler circuit to compare the separation performance of PC88A and Cyanex® 572. The ligand-metal complex strength of Cyanex® 572 provides efficient extraction of REE while significantly reducing the strip acid requirements. Reductions in chemical consumption have a significant impact on process economics for REE separations. Partitioning results summarized Table 1 indicate that Cyanex® 572 offers the same separation performance as PC88A while reducing acid consumption by 30% in the strip section for the mid/heavy REE separation. Flowsheet Effluent Compositions PC88A Cyanex® 572 Raffinate Mid REE Heavy REE 99.40% 0.60% 99.40% 0.60% Rich Mid REE Heavy REE 2.20% 97.80% 0.80% 99.20% Liquor Strip Acid Required 3.4 M 2.3 M Table 1 – Flowsheet results comparing separation performance of PC88A and Cyanex® 572 for a mid/heavy REE separation.

Multi-scale graph-cut algorithm for efficient water-fat separation.

Science.gov (United States)

Berglund, Johan; Skorpil, Mikael

2017-09-01

To improve the accuracy and robustness to noise in water-fat separation by unifying the multiscale and graph cut based approaches to B 0 -correction. A previously proposed water-fat separation algorithm that corrects for B 0 field inhomogeneity in 3D by a single quadratic pseudo-Boolean optimization (QPBO) graph cut was incorporated into a multi-scale framework, where field map solutions are propagated from coarse to fine scales for voxels that are not resolved by the graph cut. The accuracy of the single-scale and multi-scale QPBO algorithms was evaluated against benchmark reference datasets. The robustness to noise was evaluated by adding noise to the input data prior to water-fat separation. Both algorithms achieved the highest accuracy when compared with seven previously published methods, while computation times were acceptable for implementation in clinical routine. The multi-scale algorithm was more robust to noise than the single-scale algorithm, while causing only a small increase (+10%) of the reconstruction time. The proposed 3D multi-scale QPBO algorithm offers accurate water-fat separation, robustness to noise, and fast reconstruction. The software implementation is freely available to the research community. Magn Reson Med 78:941-949, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

The separation and determination of trace elements in iron ore

International Nuclear Information System (INIS)

Jones, E.A.

1977-01-01

The separation, concentration, and determination of trace elements in iron ores are described. After the sample has been dissolved, the iron is separated by liquid-liquid extraction with a liquid cation-exchanger, di-(2-ethylhexyl) phosphoric acid. The trace elements aluminium, cadmium, calcium, chromium, cobalt, copper, lead, magnesium, manganese, mercury, potassium, sodium, vanadium, and zinc are determined in the aqueous phase by atomic-absorption spectrophotometry

The method of separation for evolutionary spectral density estimation of multi-variate and multi-dimensional non-stationary stochastic processes

KAUST Repository

Schillinger, Dominik

2013-07-01

The method of separation can be used as a non-parametric estimation technique, especially suitable for evolutionary spectral density functions of uniformly modulated and strongly narrow-band stochastic processes. The paper at hand provides a consistent derivation of method of separation based spectrum estimation for the general multi-variate and multi-dimensional case. The validity of the method is demonstrated by benchmark tests with uniformly modulated spectra, for which convergence to the analytical solution is demonstrated. The key advantage of the method of separation is the minimization of spectral dispersion due to optimum time- or space-frequency localization. This is illustrated by the calibration of multi-dimensional and multi-variate geometric imperfection models from strongly narrow-band measurements in I-beams and cylindrical shells. Finally, the application of the method of separation based estimates for the stochastic buckling analysis of the example structures is briefly discussed. © 2013 Elsevier Ltd.

Multi-element analysis for environmental characterization and its future trends

International Nuclear Information System (INIS)

Sansoni, B.

1987-04-01

Before starting to characterize the environment by its elemental composition, it may be useful to ask about the objective of these efforts. This includes questions about the scope of environmental protection, the definition of the environment and the limitations of its characterization by elemental composition alone. In the second part of this lecture, examples are given of the elemental composition of well analysed samples from the atmosphere, hydrosphere, lithosphere and biosphere. The third part introduces the principle of multi-element analysis and the fourth part gives examples. Finally, future aspects of modern chemical analysis are outlined with respect to the multi-element principle. (orig.)

Rapid separation of individual rare-earth elements from fission products

International Nuclear Information System (INIS)

Baker, J.D.; Gehrke, R.J.; Greenwood, R.C.; Meikrantz, D.H.

1980-01-01

A microprocessor-controlled radiochemical separation system has been developed to rapidly separate rare-earth elements from gross fission products. The system is composed of two high performance liquid chromatography columns coupled in series by a stream-splitting injection valve. The first column separates the rare-earth group by extraction chromatography using dihexyldiethylcarbamylmethylenephosphonate (DHDECMP) adsorbed on Vydac C 8 resin. The second column isolates the individual rare-earth elements by cation exchange using Aminex A-9 resin with α-hydroxyisobutyric acid (α-HIBA) as the eluent. With this system, fission-product rare-earth isotopes with half-lives as short as three minutes have been studied

Reducing Data Size Inequality during Finite Element Model Separation into Superelements

Directory of Open Access Journals (Sweden)

Yu. V. Berchun

2015-01-01

Full Text Available The work considers two methods of automatic separation of final element model into super-elements to decrease computing resource demand when solving the linearly - elastic problems of solid mechanics. The first method represents an algorithm to separate a final element grid into simply connected sub-regions according to the set specific number of nodes in the super-element. The second method is based on the generation of a super-element with the set specific data size of the coefficient matrix of the system of equations of the internal nodes balance, which are eliminated during super-element transformation. Both methods are based on the theory of graphs. The data size of a matrix of coefficients is assessed on the assumption that the further solution of a task will use Holetsky’s method. Before assessment of data size, a KatkhillaMackey's (Cuthill-McKee algorithm renumbers the internal nodes of a super-element both to decrease a profile width of the appropriate matrix of the system of equations of balance and to reduce the number of nonzero elements. Test examples show work results of abovementioned methods compared in terms of inequality of generated super-element separation according to the number of nodes and data size of the coefficient matrix of the system of equations of the internal nodes balance. It is shown that the offered approach provides smaller inequality of data size of super-element matrixes, with slightly increasing inequality by the number of tops.

Experimental study of multi-component separation by gas centrifuge

International Nuclear Information System (INIS)

Zhou, M.S.; Liang, X.W.; Chen, W.N.; Yin, Y.T.

2006-01-01

Stable isotopes are applied in many areas and most stable isotopes are multi-component, This paper presents experimental results of several stable isotopes separation conducted in Tsinghua University by using ultra-speed gas centrifuges. Xe, WF 6 , TeF 6 , SiHCl 3 , SiF 4 were chosen as the process gases. By adjusting some of the centrifuge's parameters, the suitable centrifuge parameters for different process gas separations were found and the overall unit separation factors γ 0 were obtained by means of single gas centrifuge separation. The experimental results show that with appropriate process gases, stable isotope separation by gas centrifuge was effective. (authors)

Some Chemical Group Separations of Radioactive Trace Elements

Energy Technology Data Exchange (ETDEWEB)

Samsahl, K

1962-06-15

As a pretreatment for gamma spectrometric analysis methods have been developed for the chemical separation of traces of P, Sc, Ge, As, Se, Br, Zr, Nb, Ru, Ag, Cd, Sn, Sb, I, Hf, Ta, Re, Os, Au and Hg into 9 different groups. By combining the present methods with already existing chemical group separation methods for traces of Na, K, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Rb, Sr, Mo, In, Fe, Cs, Ba, L.a, the rare earths, W and Ir, a complete separation scheme comprising 15 groups of elements has been worked out. The chemical 15-group separation method has been advantageously used in gamma spectrometric routine analysis of biological materials.

Some Chemical Group Separations of Radioactive Trace Elements

International Nuclear Information System (INIS)

Samsahl, K.

1962-06-01

As a pretreatment for gamma spectrometric analysis methods have been developed for the chemical separation of traces of P, Sc, Ge, As, Se, Br, Zr, Nb, Ru, Ag, Cd, Sn, Sb, I, Hf, Ta, Re, Os, Au and Hg into 9 different groups. By combining the present methods with already existing chemical group separation methods for traces of Na, K, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Rb, Sr, Mo, In, Fe, Cs, Ba, L.a, the rare earths, W and Ir, a complete separation scheme comprising 15 groups of elements has been worked out. The chemical 15-group separation method has been advantageously used in gamma spectrometric routine analysis of biological materials

Multi-element probabilistic collocation method in high dimensions

International Nuclear Information System (INIS)

Foo, Jasmine; Karniadakis, George Em

2010-01-01

We combine multi-element polynomial chaos with analysis of variance (ANOVA) functional decomposition to enhance the convergence rate of polynomial chaos in high dimensions and in problems with low stochastic regularity. Specifically, we employ the multi-element probabilistic collocation method MEPCM and so we refer to the new method as MEPCM-A. We investigate the dependence of the convergence of MEPCM-A on two decomposition parameters, the polynomial order μ and the effective dimension ν, with ν<< N, and N the nominal dimension. Numerical tests for multi-dimensional integration and for stochastic elliptic problems suggest that ν≥μ for monotonic convergence of the method. We also employ MEPCM-A to obtain error bars for the piezometric head at the Hanford nuclear waste site under stochastic hydraulic conductivity conditions. Finally, we compare the cost of MEPCM-A against Monte Carlo in several hundred dimensions, and we find MEPCM-A to be more efficient for up to 600 dimensions for a specific multi-dimensional integration problem involving a discontinuous function.

Development of a relatively cheap and simple automated separation system for a routine separation procedure based on extraction chromatography

International Nuclear Information System (INIS)

Petro Zoriy; Reinhold Flucht; Mechthild Burow; Peter Ostapczuk; Reinhard Lennartz; Myroslav Zoriy

2010-01-01

A robust analytical method has been developed in our laboratory for the separation of radionuclides by means of extraction chromatography using an automated separation system. The proposed method is both cheap and simple and provides the advantageous, rapid and accurate separation of the element of interest. The automated separation system enables a shorter separation time by maintaining a constant flow rate of solution and by avoiding clogging or bubbling in the chromatographic column. The present separation method was tested with two types of samples (water and urine) using UTEVA-, TRU- and Sr-specific resins for the separation of U, Th, Am, Pu and Sr. The total separation time for one radionuclide ranged from 60 to 100 min with the separation yield ranging from 68 to 98% depending on the elements separated. We used ICP-QMS, multi-low-level counter and alpha spectroscopy to measure the corresponding elements. (author)

Separations chemistry for f elements: Recent developments and historical perspective

International Nuclear Information System (INIS)

Nash, K.L.; Choppin, G.R.

1995-01-01

With the end of the cold war, the principal mission in actinide separations has changed from production of plutonium to cleanup of the immense volume of moderately radioactive mixed wastes which resulted from fifty years of processing activities. In order to approach the cleanup task from a proper perspective, it is necessary to understand the nature of the problem and how the wastes were generated. In this report, the history of actinide separations, both the basic science and production aspects, is examined. Many of the separations techniques in use today were developed in the 40's and 50's for the identification and production of actinide elements. To respond to the modern world of actinide separations new techniques are being developed for separations ranging from analytical methods to detect ultra-trace concentrations (for bioassay and environmental monitoring) to large scale waste treatment procedures. Some of these new methods are ''improvements'' or adaptations of the historical techniques. Total actinide recovery, lanthanide/actinide separations, and selective partitioning of actinides from inert constituents are of primary concern. This report, offers a historical perspective, review the current status of f element separation processes, and suggest areas for continued research in both actinide separations and waste cleanup/environment remediation

Integrated Process Design and Control of Multi-element Reactive Distillation Processes

DEFF Research Database (Denmark)

Mansouri, Seyed Soheil; Sales-Cruz, Mauricio; Huusom, Jakob Kjøbsted

2016-01-01

In this work, integrated process design and control of reactive distillation processes involving multi-elements is presented. The reactive distillation column is designed using methods and tools which are similar in concept to non-reactive distillation design methods, such as driving force approach....... The methods employed in this work are based on equivalent element concept. This concept facilitates the representation of a multi-element reactive system as equivalent binary light and heavy key elements. First, the reactive distillation column is designed at the maximum driving force where through steady...

Technical possibilities to support separation of radioactive elements from metallic waste

International Nuclear Information System (INIS)

Bjoerkvall, Johan; Ye, Guozhu; Lindberg, Maria

2014-01-01

In the nuclear industry metallic objects can be either surface or bulk contaminated. Surface contaminated objects are often decontaminated by chemical or mechanical means, but are there other possibilities? During melting slags are formed either spontaneously or by adding slag forming compounds. However, one question that frequently arises is: Can all nuclides be separated by adding slag forming compounds? This question is not entirely correct as it is not only the radioactive nuclides that are separated from the metal but all atoms of that element present in the melt, radioactive and stable isotopes alike. Part of the answer lays in thermodynamics. Thermodynamics cannot positively answer the question with yes, as there are also practical and economical aspects to take into account, but if the answer is no there will never be any practical or economical efforts that will override nature. This paper will describe the theoretical baseline for evaluating the possibilities to separate certain elements during the melting process, mainly from steel but other metals will also touched on. The most common elements that have radioactive isotopes of interest is of course cobalt (Co-60, Co-58), but other elements of interest are manganese (Mn-54), strontium (Sr- 90), antimony (Sb-125) and of course heavy elements such as uranium, plutonium and americium. The paper will also describe methods used in the normal metal melting industry to separate elements from the base metal melted. This section will cover practical methods used as well as developed methods that are very seldom used due to time or financial constraints. (authors)

Light element thermodynamics related to actinide separations

International Nuclear Information System (INIS)

Johnson, I.; Johnson, C.E.

1997-01-01

The accumulation of waste from the last five decades of nuclear reactor development has resulted in large quantities of materials of very diverse chemical composition. An electrometallurgical (EM) method is being developed to separate the components of the waste into several unique streams suitable for permanent disposal and an actinide stream suitable for retrievable storage. The principal types of nuclear wastes are spent oxide or metallic fuel. Since the EM module requires a metallic feed, and oxygen interferes with its operation, the oxide fuel has to be reduced prior to EM treatment. Further, the wastes contain, in addition to oxygen, other light elements (first- and second-row elements) that may also interfere with the operation of the EM module. The extent that these light elements interfere with the operation of the EM module has been determined by chemical thermodynamic calculations. (orig.)

Multi-element analysis of unidentified fallen objects from Tatale in ...

African Journals Online (AJOL)

A multi-element analysis has been carried out on two fallen objects, # 01 and # 02, using instrumental neutron activation analysis technique. A total of 17 elements were identified in object # 01 while 21 elements were found in object # 02. The two major elements in object # 01 were Fe and Mg, which together constitute ...

Electro-kinetic separation of rare earth elements using a redox-active ligand

Energy Technology Data Exchange (ETDEWEB)

Fang, Huayi; Cole, Bren E.; Qiao, Yusen; Bogart, Justin A.; Cheisson, Thibault; Manor, Brian C.; Carroll, Patrick J.; Schelter, Eric J. [Department of Chemistry, University of Pennsylvania, Philadelphia, PA (United States)

2017-10-16

Purification of rare earth elements is challenging due to their chemical similarities. All of the deployed separation methods rely on thermodynamic properties, such as distribution equilibria in solvent extraction. Rare-earth-metal separations based on kinetic differences have not been examined. Herein, we demonstrate a new approach for rare-earth-element separations by exploiting differences in the oxidation rates within a series of rare earth compounds containing the redox-active ligand [{2-(tBuN(O))C_6H_4CH_2}{sub 3}N]{sup 3-}. Using this method, a single-step separation factor up to 261 was obtained for the separation of a 50:50 yttrium-lutetium mixture. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

Electromagnetic separator for light and middle isotope elements

International Nuclear Information System (INIS)

Bernas, R.

1952-01-01

We describe a separator of isotope with a 60 deg magnetic sector that permits, thanks to a process of neutralization of the space charge, to use efficiently intense ion beams. The ion source for solid is essentially constituted by a discharge of hot cathode in a magnetic field and provides an ion beam focused of more than 10 mA. The result of the first separations (Zn, Sb, Hg) indicates that the isotopes of various elements can be obtained in quantities varying from 10 to 100 mg/24 hours. (author) [fr

Use of coextraction and suppression of extraction in extraction-chromatographic separation of elements

International Nuclear Information System (INIS)

Karandashev, V.K.; Kuznetsov, R.A.; Grazhulene, S.S.; Usmanova, M.M.

1988-01-01

TBP, solutions of hydrobromic acid, indium and polytetrafluoroethylene powder, carrier for TBP, were used to study the effects of coextraction and extraction suppression on extraction-chromatographic behaviour of microamounts of elements in the presence of macroamounts of other elements. Possibility of using these effects under extraction-chromatographic element separation were considered. A new method for extraction-chromatographic separation of scandium microamounts from the mixture of large amount of elements (Y, Cd, Ce, Eu, Lu, Hf, Ta, W, Np and other) was suggested. 15 refs.; 3 figs

Limitation of multi-elemental fingerprinting of wheat grains: Effect of cultivar, sowing date, and nutrient management

DEFF Research Database (Denmark)

Suarez-Tapia, Alfonso; Kucheryavskiy, Sergey V.; Christensen, Bent Tolstrup

2017-01-01

Multi-element fingerprinting demonstrates some potential for tracing the origin of agricultural products but not for discriminating among crop cultivars and nutrient management (source, rate). With principal component analysis (PCA) and univariate statistics, we examined 19 elements in grains from...... two winter wheat cultivars (Hereford, Mariboss) grown with different rates of animal manure (AM) or mineral fertilisers (NPK) in a long-term field experiment and two sowing dates (early, timely). Nitrogen, Cd and Mn related to NPK, and Mo and Na to AM. Barium, Fe, and P reflected nutrient rate......; these elements increased with nutrient rate regardless of source. Unmanured grains were enriched in Cu. Mariboss was characterized by higher concentrations of Sr, Ba and Sc compared to Hereford with Sr in grain as the main separator. Univariate statistics showed higher concentrations of N, P, Mg, Ba, Cu, Mo...

Coulomb matrix elements in multi-orbital Hubbard models.

Science.gov (United States)

Bünemann, Jörg; Gebhard, Florian

2017-04-26

Coulomb matrix elements are needed in all studies in solid-state theory that are based on Hubbard-type multi-orbital models. Due to symmetries, the matrix elements are not independent. We determine a set of independent Coulomb parameters for a d-shell and an f-shell and all point groups with up to 16 elements (O h , O, T d , T h , D 6h , and D 4h ). Furthermore, we express all other matrix elements as a function of the independent Coulomb parameters. Apart from the solution of the general point-group problem we investigate in detail the spherical approximation and first-order corrections to the spherical approximation.

Multi Elemental Study Using Prompt Gamma Technique

International Nuclear Information System (INIS)

Normanshah Dahing; Muhamad Samudi Yasir; Normanshah Dahing; Hanafi Ithnin; Mohd Fitri Abdul Rahman; Hearie Hassan

2016-01-01

In this study, principle of prompt gamma neutron activation analysis has been used as a technique to determine the elements in the sample. The system consists of collimated isotopic neutron source, Cf-252 with HPGe detector and Multichannel Analysis (MCA). Concrete with size of 10x10x10 cm 3 and 15x15x15 cm 3 were analysed as sample. When neutrons enter and interact with elements in the concrete, the neutron capture reaction will occur and produce characteristic prompt gamma ray of the elements. The preliminary result of this study demonstrate the major element in the concrete was determined such as Si, Mg, Ca, Al, Fe and H as well as others element, such as Cl by analysis the gamma ray lines respectively. The results obtained were compared with computer simulation, NAA and XRF as a part of reference and validation. The potential and the capability of neutron induced prompt gamma as tool for multi elemental analysis qualitatively to identify the elements present in the concrete sample discussed. (author)

The separation of trace elements in manganese dioxide

International Nuclear Information System (INIS)

Jones, E.A.; Dixon, K.

1981-01-01

Separations from manganese are discribed for (a)Al(III), Mo(VI), V(V), and Ti(IV), and (b)trace elements in general. In the first separation, a combined anion-cation exchange, the oxalate complexes are absorbed onto the anionic BIO.RAD 1-X8 resin. V(V) and Al(III) are then eluted into a cation-exchange column from which they are eluted successively, Mo(VI) and Ti(IV) then being eluted from the anionic resin. In the second separation, up to 2g of manganese is absorbed onto BIO.RAD AG 50W-X8 resin, from which V(V) is eluted with dilute hydrochloric acid prior to the elution of Co(II), Cu(II), Zn(II), Cd(II), Fe(III), As(III), Sb(III), Mo(VI), W(VI), and Sn(II) with a mixture of 1 M hydrochloric acid, 80 per cent acetone, and 0,1 per cent hydrogen peroxide. Mn(11) is eluted next with a mixture of 0,75M hydrochloric acid and 90 per cent acetone, after which the remaining cations are eluted with 4M hydrochloric acid. Satisfactory recoveries ranging from 0,8 to 60 mg/l were obtained for 18 of the 21 elements tested. After concentration by evaporation, final measurements were made by the use of atomic-absorption spectrophotometry, or direct-reading spectrometry with excitation from an inductively coupled plasma source. Comparative results were obtained with atomic-absorption procedures where the manganese was not separated. However, the separation procedure can reduce the time required for analysis by the direct method because it limits the number of dilutions necessary and eliminates the need for the use of the method of additions to compensate for interferences from manganese

A new large solid angle multi-element silicon drift detector system for low energy X-ray fluorescence spectroscopy

Science.gov (United States)

Bufon, J.; Schillani, S.; Altissimo, M.; Bellutti, P.; Bertuccio, G.; Billè, F.; Borghes, R.; Borghi, G.; Cautero, G.; Cirrincione, D.; Fabiani, S.; Ficorella, F.; Gandola, M.; Gianoncelli, A.; Giuressi, D.; Kourousias, G.; Mele, F.; Menk, R. H.; Picciotto, A.; Rachevski, A.; Rashevskaya, I.; Sammartini, M.; Stolfa, A.; Zampa, G.; Zampa, N.; Zorzi, N.; Vacchi, A.

2018-03-01

Low-energy X-ray fluorescence (LEXRF) is an essential tool for bio-related research of organic samples, whose composition is dominated by light elements. Working at energies below 2 keV and being able to detect fluorescence photons of lightweight elements such as carbon (277 eV) is still a challenge, since it requires in-vacuum operations to avoid in-air photon absorption. Moreover, the detectors must have a thin entrance window and collect photons at an angle of incidence near 90 degrees to minimize the absorption by the protective coating. Considering the low fluorescence yield of light elements, it is important to cover a substantial part of the solid angle detecting ideally all emitted X-ray fluorescence (XRF) photons. Furthermore, the energy resolution of the detection system should be close to the Fano limit in order to discriminate elements whose XRF emission lines are often very close within the energy spectra. To ensure all these features, a system consisting of four monolithic multi-element silicon drift detectors was developed. The use of four separate detector units allows optimizing the incidence angle on all the sensor elements. The multi-element approach in turn provides a lower leakage current on each anode, which, in combination with ultra-low noise preamplifiers, is necessary to achieve an energy resolution close to the Fano limit. The potential of the new detection system and its applicability for typical LEXRF applications has been proved on the Elettra TwinMic beamline.

Emitter signal separation method based on multi-level digital channelization

Science.gov (United States)

Han, Xun; Ping, Yifan; Wang, Sujun; Feng, Ying; Kuang, Yin; Yang, Xinquan

2018-02-01

To solve the problem of emitter separation under complex electromagnetic environment, a signal separation method based on multi-level digital channelization is proposed in this paper. A two-level structure which can divide signal into different channel is designed first, after that, the peaks of different channels are tracked using the track filter and the coincident signals in time domain are separated in time-frequency domain. Finally, the time domain waveforms of different signals are acquired by reverse transformation. The validness of the proposed method is proved by experiment.

Micro-scaled high-throughput digestion of plant tissue samples for multi-elemental analysis

Directory of Open Access Journals (Sweden)

Husted Søren

2009-09-01

Full Text Available Abstract Background Quantitative multi-elemental analysis by inductively coupled plasma (ICP spectrometry depends on a complete digestion of solid samples. However, fast and thorough sample digestion is a challenging analytical task which constitutes a bottleneck in modern multi-elemental analysis. Additional obstacles may be that sample quantities are limited and elemental concentrations low. In such cases, digestion in small volumes with minimum dilution and contamination is required in order to obtain high accuracy data. Results We have developed a micro-scaled microwave digestion procedure and optimized it for accurate elemental profiling of plant materials (1-20 mg dry weight. A commercially available 64-position rotor with 5 ml disposable glass vials, originally designed for microwave-based parallel organic synthesis, was used as a platform for the digestion. The novel micro-scaled method was successfully validated by the use of various certified reference materials (CRM with matrices rich in starch, lipid or protein. When the micro-scaled digestion procedure was applied on single rice grains or small batches of Arabidopsis seeds (1 mg, corresponding to approximately 50 seeds, the obtained elemental profiles closely matched those obtained by conventional analysis using digestion in large volume vessels. Accumulated elemental contents derived from separate analyses of rice grain fractions (aleurone, embryo and endosperm closely matched the total content obtained by analysis of the whole rice grain. Conclusion A high-throughput micro-scaled method has been developed which enables digestion of small quantities of plant samples for subsequent elemental profiling by ICP-spectrometry. The method constitutes a valuable tool for screening of mutants and transformants. In addition, the method facilitates studies of the distribution of essential trace elements between and within plant organs which is relevant for, e.g., breeding programmes aiming at

XRF and TXRF techniques for multi-element determination of trace elements in whole blood and human hair samples

International Nuclear Information System (INIS)

Khuder, A.; Karjou, J.; Sawan, M.Kh.; Bakir, M.A.

2007-01-01

XRF and TXRF were established as useful techniques for multi-element analysis of whole blood and human head hair samples. Direct-XRF with different collimation units and different X-ray excitation modes was successfully used for the determination of S, P, K, Ca, Fe, and Br elements in blood samples and K, Ca, Mn, Fe elements in human hair samples. Direct analysis by TXRF was used for the determination of Rb and Sr in digested blood and human hair samples, respectively, while, the co-precipitation method using APDC for TXRF analysis was used for the determination of Ni, Cu, Zn, and Pb elements in both matrices. As a result, the improved XRF and TXRF methods were applied for multi-element determination of elements in whole blood and human hair samples in non-occupational exposed population living in Damascus city. The mean concentrations of analyzed elements in both matrices were on the reported range values for non-occupational population in other countries. (author)

XRF and TXRF techniques for multi-element determination of trace elements in whole blood and human hair samples

International Nuclear Information System (INIS)

Khuder, A.; Karjou, J.; Sawan, M.Kh.; Bakir, M.A.

2008-01-01

XRF and TXRF were established as useful techniques for multi-element analysis of whole blood and human head hair samples. Direct-XRF with different collimation units and different X-ray excitation modes was successfully used for the determination of S, P, K, Ca, Fe, and Br elements in blood samples and K, Ca, Mn, Fe elements in human hair samples. Direct analysis by TXRF was used for the determination of Rb and Sr in digested blood and human hair samples, respectively, while, the co-precipitation method using APDC for TXRF analysis was used for the determination of Ni, Cu, Zn, and Pb elements in both matrices. As a result, the improved XRF and TXRF methods were applied for multi-element determination of elements in whole blood and human hair samples in non-occupational exposed population living in Damascus city. The mean concentrations of analyzed elements in both matrices were on the reported range values for non-occupational population in other countries. (author)

Development of Radiochemical Separation Technology

Energy Technology Data Exchange (ETDEWEB)

Lee, Eil Hee; Kim, K. W.; Yang, H. B. (and others)

2007-06-15

This project of the second phase was aimed at the development of basic unit technologies for advanced partitioning, and the application tests of pre-developed partitioning technologies for separation of actinides by using a simulated multi-component radioactive waste containing Am, Np, Tc, U and so on. The goals for recovery yield of TRU, and for purity of Tc are high than 99% and about 99%, respectively. The work scopes and contents were as follows. 1). For the development of basic unit technologies for advanced partitioning. 1. Development of technologies for co-removal of TRU and for mutual separation of U and TRU with a reduction-complexation reaction. 2. Development of extraction system for high-acidity co-separation of An(+3) and Ln(+3) and its radiolytic evaluation. 3. Synthesis of extractants for the selective separation of An(+3) and its relevant extraction system development. 4. Development of a hybrid system for the recovery of noble metals and its continuous separation tests. 5. Development of electrolytic system for the decompositions of N-NO3 and N-NH3 compounds to nitrogen gas. 2). For the application test of pre-developed partitioning technologies for the separation of actinide elements in a simulated multi-component solution equivalent to HLW level. 1. Co-separation of Tc, Np and U by a (TBP-TOA)/NDD system. 2. Mutual-separation of Am, Cm and RE elements by a (Zr-DEHPA)/NDD system. All results will be used as the fundamental data for the development of advanced partitioning process in the future.

Multi-column step-gradient chromatography system for automated ion exchange separations

International Nuclear Information System (INIS)

Rucker, T.L.

1985-01-01

A multi-column step-gradient chromatography system has been designed to perform automated sequential separations of radionuclides by ion exchange chromatography. The system consists of a digital programmer with automatic stream selection valve, two peristaltic pumps, ten columns, and a fraction collector. The automation allows complicated separations of radionuclides to be made with minimal analyst attention and allows for increased productivity and reduced cost of analyses. Results are reported for test separations on mixtures of radionuclides by the system

Validation of multi-element isotope dilution ICPMS for the analysis of basalts

Energy Technology Data Exchange (ETDEWEB)

Willbold, M.; Jochum, K.P.; Raczek, I.; Amini, M.A.; Stoll, B.; Hofmann, A.W. [Max-Planck-Institut fuer Chemie, Mainz (Germany)

2003-09-01

In this study we have validated a newly developed multi-element isotope dilution (ID) ICPMS method for the simultaneous analysis of up to 12 trace elements in geological samples. By evaluating the analytical uncertainty of individual components using certified reference materials we have quantified the overall analytical uncertainty of the multi-element ID ICPMS method at 1-2%. Individual components include sampling/weighing, purity of reagents, purity of spike solutions, calibration of spikes, determination of isotopic ratios, instrumental sources of error, correction of mass discrimination effect, values of constants, and operator bias. We have used the ID-determined trace elements for internal standardization to improve indirectly the analysis of 14 other (mainly mono-isotopic trace elements) by external calibration. The overall analytical uncertainty for those data is about 2-3%. In addition, we have analyzed USGS and MPI-DING geological reference materials (BHVO-1, BHVO-2, KL2-G, ML3B-G) to quantify the overall bias of the measurement procedure. Trace element analysis of geological reference materials yielded results that agree mostly within about 2-3% relative to the reference values. Since these results match the conclusions obtained by the investigation of the overall analytical uncertainty, we take this as a measure for the validity of multi-element ID ICPMS. (orig.)

Multi-Element Lean Direct Injection Combustor Module, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — We propose to develop a Multi-Element Lean Direct Injection, ME-LDI, Combustion concept with the following innovative features: 1. Independent, mini burning zones...

Theoretical study on separation of H2/HD by multi-column interlinking cryogenic distillation

International Nuclear Information System (INIS)

Xia Xiulong

2010-01-01

Multi-column interlinking is an effective separation method adopted for enrichment of trace deuterium and tritium. Conceptual design and proper operating mode were proposed for separation of H2/HD by cryogenic distillation with three interlinking columns,and separation performance were obtained.Enrichment of 20 x 10 x 10 achieved with proper operating mode indicating multi-column interlinking is specially suitable for trace composition enrichment. Pressure and reflux ratio' effect on separation performance were also investigated. As pressure increased from 0.6 atm to 1.5 atm, deuterium stripping efficiency dropped from 99.79% to 99.44%; As reflux ratio increased from 3 to 5, deuterium stripping efficiency increased from 99.67% to 99.81%. (authors)

Infinite elements for soil-structure interaction analysis in multi-layered halfspaces

International Nuclear Information System (INIS)

Yun, Chung Bang; Kim, Jae Min; Yang, Shin Chu

1994-01-01

This paper presents the theoretical aspects of a computer code (KIESSI) for soil-structure interaction analysis in a multi-layered halfspace using infinite elements. The shape functions of the infinite elements are derived from approximate expressions of the analytical solutions. Three different infinite elements are developed. They are the horizontal, the vertical and the comer infinite elements (HIE, VIE and CIE). Numerical example analyses are presented for demonstrating the effectiveness of the proposed infinite elements

Stacked white OLED having separate red, green and blue sub-elements

Energy Technology Data Exchange (ETDEWEB)

Forrest, Stephen; Qi, Xiangfei; Slootsky, Michael

2015-06-23

The present invention relates to efficient organic light emitting devices (OLEDs). More specifically, the present invention relates to white-emitting OLEDs, or WOLEDs. The devices of the present invention employ three emissive sub-elements, typically emitting red, green and blue, to sufficiently cover the visible spectrum. The sub-elements are separated by charge generating layers.

Stacked white OLED having separate red, green and blue sub-elements

Science.gov (United States)

Forrest, Stephen; Qi, Xiangfei; Slootsky, Michael

2016-06-28

The present invention relates to efficient organic light emitting devices (OLEDs). More specifically, the present invention relates to white-emitting OLEDs, or WOLEDs. The devices of the present invention employ three emissive sub-elements, typically emitting red, green and blue, to sufficiently cover the visible spectrum. The sub-elements are separated by charge generating layers.

Investigations for chromatographic separation and determination of the rare earths and auxiliary group elements

International Nuclear Information System (INIS)

Post, K.

1981-01-01

Different method have been developed to quantitatively determine rare earth elements after their column chromatographic separation. The influence of the active solvents in the running systems diethyl ether/tetra hydrofuran (THF)/nitric acid (HNO 3 ) and diethyl ether/bis-(2-ethyl hexyl) phosphate (HDEHP)/HNO 3 was investigated on the column chromatographic separation of all rare earth elements is possible by the synergistic combination of the active running components THF and HDEHP. Further from product isotopes could also be separated using the running agents described here in investigations to separate fission product mixtures of irradiated uranium. (orig./HBR) [de

An improved ion-exchange separation of rare-earth elements for spectrographic analysis

International Nuclear Information System (INIS)

Jones, E.A.

1978-01-01

Rare-earth elements are separated from scandium and base metals by adsorption onto anion resin BIORAD AG1-X8 in the nitrate form from a mixture of 5 per cent 7M nitric acid and 95 per cent methanol. The yttrium subgroup is eluted with a mixture of 45 per cent 7M nitric acid and 55 per cent methanol, followed by elution of the cerium subgroup with 8M nitric acid. This separation facilitates the determination of the traces of the heavier yttrium subgroup of rare-earth elements

Separation of transuranium elements and fission products from medium activity aqueous liquid wastes

International Nuclear Information System (INIS)

Gompper, K.; Kunze, S.; Eden, G.; Loesch, G.; Zemski, C.

1986-01-01

In the course of work performed between January 1981 and June 1985 on the separation of TRU elements and fission products three liquid alpha containing waste streams were treated: - medium level waste solutions, - waste solutions from the acid digestion of burnable alpha containing solid residues, - waste solutions from mixed oxide fuel element fabrication. The method of separation was initially developed and optimized with simulating substances. Subesequently it was tested with real waste solutions

Application of pressurized ion exchange to separations of transplutonium elements

International Nuclear Information System (INIS)

Campbell, D.O.

1980-01-01

High-pressure ion exchange chromatography, used first for nucleic acid separations, was applied to the production of the heavier actinides, particularly the transcurium elements. Its use at the TRU plant is described. Future developments are considered briefly

Pump radiation distribution in multi-element first cladding laser fibres

International Nuclear Information System (INIS)

Mel'kumov, Mikhail A; Bufetov, Igor' A; Bubnov, M M; Shubin, Aleksei V; Semenov, S L; Dianov, Evgenii M

2005-01-01

Pump radiation transfer is studied experimentally in multi-element first cladding laser fibres. A model of this process is proposed, which is in good agreement with experimental results. An all-fibre single-mode cw ytterbium laser based on a three-element first cladding fibre with an output power of 100W is fabricated. (lasers)

Column extraction chromatography with HEH (EHP) for separating rare earth elements from coexistent elements and its application

International Nuclear Information System (INIS)

Peng Chunlin; Sun Baocheng; Zhao Junwu; Liu Xuan

1985-01-01

For separating rare earths from large amount of coexistent elements a new method of column extraction chromatography with HEH (EHP) as a stationary phase and sulphosalicylic acid, gluconic acid, ascorbic acid respectively as a mobile phase has been developed. It has been applied to the determination of trace rare earth elements in nickel-base alloys and iron-nickel-base alloys with satisfactory results

Application of fibrous complexing sorbents for trace elements preconcentration and separation

International Nuclear Information System (INIS)

Zakhartchenko, E.A.; Myasoedova, G.V.

2003-01-01

This article demonstrates the application of the 'filled' fibrous sorbents for preconcentration and separation of platinum metals, as well as heavy metals and radionuclides. The POLYORGS complexing sorbents and ion-exchangers were used as fillers. Dynamic preconcentration conditions should be set for complete sorption of the elements: diameter and mass of the sorbent disk or the column as well as flow rate of the solution. These conditions depend on specific features of materials to be analysed and the requirements of the experimental task or detection method. Extensive alteration of features as well as perfect kinetic properties and high selectivity of the 'filled' sorbents confirm their applicability for trace elements preconcentration and separation in technology and analytical chemistry. (authors)

Separations chemistry for actinide elements: Recent developments and historical perspective

International Nuclear Information System (INIS)

Nash, K.L.; Choppin, G.R.

1997-01-01

With the end of the cold war, the principal mission in actinide separations has changed from production of plutonium to cleanup of the immense volume of moderately radioactive mixed wastes which resulted from fifty years of processing activities. In order to approach the cleanup task from a proper perspective, it is necessary to understand how the wastes were generated. Most of the key separations techniques central to actinide production were developed in the 40's and 50's for the identification and production of actinide elements. Total actinide recovery, lanthanide/actinide separations, and selective partitioning of actinides from inert constituents are currently of primary concern. To respond to the modern world of actinide separations, new techniques are being developed for separations ranging from analytical methods to detect ultra-trace concentrations (for bioassay and environmental monitoring) to large-scale waste treatment procedures. In this report, the history of actinide separations, both the basic science and production aspects, is examined and evaluated in terms of contemporary priorities

Chemical elements in the environment: multi-element geochemical datasets from continental to national scale surveys on four continents

Science.gov (United States)

Caritat, Patrice de; Reimann, Clemens; Smith, David; Wang, Xueqiu

2017-01-01

During the last 10-20 years, Geological Surveys around the world have undertaken a major effort towards delivering fully harmonized and tightly quality-controlled low-density multi-element soil geochemical maps and datasets of vast regions including up to whole continents. Concentrations of between 45 and 60 elements commonly have been determined in a variety of different regolith types (e.g., sediment, soil). The multi-element datasets are published as complete geochemical atlases and made available to the general public. Several other geochemical datasets covering smaller areas but generally at a higher spatial density are also available. These datasets may, however, not be found by superficial internet-based searches because the elements are not mentioned individually either in the title or in the keyword lists of the original references. This publication attempts to increase the visibility and discoverability of these fundamental background datasets covering large areas up to whole continents.

Ion exchange separation of minor elements from iron for the analysis of S/G sludge

International Nuclear Information System (INIS)

Park, Kyoung Kyun; Choi, Kwang Soon; Kim, Jong Goo

2005-01-01

The chemical data of minor elements in steam generator sludge could give information about the contamination sources such as a system corrosion, an intrusion of chemicals, etc. The major component of sludge is iron. Iron of a high concentration in a measuring solution worsens the determination limit of the minor elements in a spectroscopic atom analysis. Moreover, iron has so many absorption or emission bands in a wide wavelength range that it has a spectroscopic interference on the atomic spectroscopy of various minor elements such as B, Pb, etc. Thus, the quantitative separation of minor elements from the iron matrix is essential for their determination. Gas sublimation, co-precipitation, solvent extraction and ion exchange are used for this separation. Ion exchange chromatography is applied to the separation of specific minor elements. Ion exchange method has an advantage from the point of experimental space, waste production, and number of elements when applyed to radioactive samples. This presentation describes the results of a separation of some minor elements(Al, B, Ba, Ca, Cd, Co, Cr, Cu, Gd, Mg, Mn, Mo, Nd, Ni, P, Pb, Si, Sn, Sr, Ti, V, Yb, Zn and Zr) from synthetic iron samples by anionic and cationic exchange methods for the purpose of analyzing them in the S/G sludge from a power plant

Development of the multitracer technology for a simultaneous multi-elemental analysis and its evolution in RI-beam factory project

International Nuclear Information System (INIS)

Enomoto, Shuichi

2003-01-01

This review describes the method to produce the multitracer, its biobehavior, its application for environmental sciences, Nuclear Energy Fundamentals Crossover Research (for upgrading multitracer production technology, and development of the automatic chemical separation units and of the simultaneous imaging apparatus for multi gamma-ray nuclides), and Inst. of Physical and Chemical Research (RIKEN) RI-beam factory project. The multitracer technology is an efficient (i.e., many information's are available through one experimentation) tracer technique for studying the physical, chemical and biological behavior of elements with use of their multiple radioisotopes produced by accelerators like RIKEN ring cyclotron and of computer/semiconductor detector for their individual gamma-ray spectrometry. The multitracer elements are produced in their carrier-free forms by irradiation of the target element with the heavy particle (up to Ta, in RIKEN cyclotron) and by resultant nuclear fragmentation of the target. The multitracer through nuclear fragmentation and/or fission with an automated separation apparatus will be sophisticatedly supplied in future. GREI (gamma-ray emission imaging) is under investigation. The RI-beam factory project aims to irradiate/accelerate the radioisotope, which is expected to give novel knowledge's in biology like metabolic physiology. (N.I.)

Computation of subsonic flow around airfoil systems with multiple separation

Science.gov (United States)

Jacob, K.

1982-01-01

A numerical method for computing the subsonic flow around multi-element airfoil systems was developed, allowing for flow separation at one or more elements. Besides multiple rear separation also sort bubbles on the upper surface and cove bubbles can approximately be taken into account. Also, compressibility effects for pure subsonic flow are approximately accounted for. After presentation the method is applied to several examples and improved in some details. Finally, the present limitations and desirable extensions are discussed.

Volatile and non-volatile elements in grain-size separated samples of Apollo 17 lunar soils

International Nuclear Information System (INIS)

Giovanoli, R.; Gunten, H.R. von; Kraehenbuehl, U.; Meyer, G.; Wegmueller, F.; Gruetter, A.; Wyttenbach, A.

1977-01-01

Three samples of Apollo 17 lunar soils (75081, 72501 and 72461) were separated into 9 grain-size fractions between 540 and 1 μm mean diameter. In order to detect mineral fractionations caused during the separation procedures major elements were determined by instrumental neutron activation analyses performed on small aliquots of the separated samples. Twenty elements were measured in each size fraction using instrumental and radiochemical neutron activation techniques. The concentration of the main elements in sample 75081 does not change with the grain-size. Exceptions are Fe and Ti which decrease slightly and Al which increases slightly with the decrease in the grain-size. These changes in the composition in main elements suggest a decrease in Ilmenite and an increase in Anorthite with decreasing grain-size. However, it can be concluded that the mineral composition of the fractions changes less than a factor of 2. Samples 72501 and 72461 are not yet analyzed for the main elements. (Auth.)

Numerical solution of multi group-Two dimensional- Adjoint equation with finite element method

International Nuclear Information System (INIS)

Poursalehi, N.; Khalafi, H.; Shahriari, M.; Minoochehr

2008-01-01

Adjoint equation is used for perturbation theory in nuclear reactor design. For numerical solution of adjoint equation, usually two methods are applied. These are Finite Element and Finite Difference procedures. Usually Finite Element Procedure is chosen for solving of adjoint equation, because it is more use able in variety of geometries. In this article, Galerkin Finite Element method is discussed. This method is applied for numerical solving multi group, multi region and two dimensional (X, Y) adjoint equation. Typical reactor geometry is partitioned with triangular meshes and boundary condition for adjoint flux is considered zero. Finally, for a case of defined parameters, Finite Element Code was applied and results were compared with Citation Code

Use of cationites for separation of transplutonium elements from other elements from aqueous and aqua-alcohol solutions of hydrochloric and nitric acids

International Nuclear Information System (INIS)

Guseva, L.I.; Tikhomirova, G.S.

1984-01-01

The behaviour of Am, Cm, Pu and certain fragment elements (Cs, Sr, Y, Zr, Nb, Ru, Eu) on cationite dauex-50 in aqueous and aqueous-alcohol solutions of HCl and HNO 3 has been studied. Dependences of distribution coefficients and separation factors of the elements on the acid concentration and alcohol content in the solutions are presented. The sorption of TPE by cationite from HCl and HNO 3 solutions in the presence of alcohol is shown to increase over the range of concentrations studied (from 0.5 mol/L to 4-5 mol/L), which is explained by the salting-out effect of alcohol. The distribution coefficients of TPE in the solutions, containing >= 50% alcohol, constitute >= 10 2 . The distribution coefficients of the fragment elements in the presence of alcohol also increase, but to a considerably lesser extent, which results in a better separation. The study of the washing-out curves has shown that, to separate TPE from fragment elements on cationites, both HCl and HNO 3 solutions can be used, at that, in the case of aqueous solutions a better separation is attained at acid concentration, equal to 1 mol/L, and in the case of eluating by aqueous-alcohol solutions a good separation is achieved at hig-her concentrations of the acids as well

Multi-configuration time-dependent density-functional theory based on range separation

DEFF Research Database (Denmark)

Fromager, E.; Knecht, S.; Jensen, Hans Jørgen Aagaard

2013-01-01

Multi-configuration range-separated density-functional theory is extended to the time-dependent regime. An exact variational formulation is derived. The approximation, which consists in combining a long-range Multi-Configuration- Self-Consistent Field (MCSCF) treatment with an adiabatic short...... (srGGA) approximations. As expected, when modeling long-range interactions with the MCSCF model instead of the adiabatic Buijse-Baerends density-matrix functional as recently proposed by Pernal [J. Chem. Phys. 136, 184105 (2012)10.1063/1.4712019], the description of both the 1D doubly-excited state...

Multi-element trace analysis of solid samples using one-photon two-step RIMS

International Nuclear Information System (INIS)

Telle, H. H.; Abraham, C. J.; Jones, O. R.; Krustev, T.

1998-01-01

In this study we have investigated the feasibility of multi-element analysis using a simple 1+1 photo-excitation/photo-ionization scheme. Although such schemes are usually far from ideal for optimum resonance ionization, they are the approach of choice if one wishes to maintain a simple, easy-to-operate laser set-up which is potentially suitable for routine analysis. In addition, we only made use of the second-harmonic tuning range of a single dye. While this limits the range of elements which are accessible in the 1+1 RIS scheme it further adds to the simplicity and allows for automation of sequential multi-element analysis

Yttrium separation of Xenotime waste in Pitinga (Brazil), in order to obtain rare earth elements

International Nuclear Information System (INIS)

Melo.

1996-01-01

The xenotime (YPO 4 and rare earth elements) found in the mine of Pitinga, Amazonas State, Brazil, has its origin in a primal depository ('eluvio' kind) of cassiterite, having considerable quantities of zirconite, ilmenite, topaz and niobates-tantalates. This xenotime has different characteristics in relation of the depositories that exist in other countries for presenting more concentration of rare earth heavy oxides. The mineralization of this cassiterite is problematic, because of the high level of radioactive elements. In the present work, we will process only the xenotime. The separation of rare earth elements is very difficult due to their great chemical similarity. For a more exactly determination, it is necessary to separate them at least of the macron constituents of the sample. As the Yttrium is considerate one of the rare earth elements, due to its chemical similarity, we can understand the difficulty of a chemical separation, mainly when this one is also a macro constituent of the sample, as in the case of xenotime. The process of separation will be based on the little difference that exists between the constants of complexation and the fluoride. (authors). 5 refs., 1 fig., 2 tabs

Multi-interface Level Sensors and New Development in Monitoring and Control of Oil Separators

Directory of Open Access Journals (Sweden)

Wuqiang Yang

2006-04-01

Full Text Available In the oil industry, huge saving may be made if suitable multi-interface levelmeasurement systems are employed for effectively monitoring crude oil separators andefficient control of their operation. A number of techniques, e.g. externally mounteddisplacers, differential pressure transmitters and capacitance rod devices, have beendeveloped to measure the separation process with gas, oil, water and other components.Because of the unavailability of suitable multi-interface level measurement systems, oilseparators are currently operated by the trial-and-error approach. In this paper someconventional techniques, which have been used for level measurement in industry, and newdevelopment are discussed.

Statistical Methods in Assembly Quality Management of Multi-Element Products on Automatic Rotor Lines

Science.gov (United States)

Pries, V. V.; Proskuriakov, N. E.

2018-04-01

To control the assembly quality of multi-element mass-produced products on automatic rotor lines, control methods with operational feedback are required. However, due to possible failures in the operation of the devices and systems of automatic rotor line, there is always a real probability of getting defective (incomplete) products into the output process stream. Therefore, a continuous sampling control of the products completeness, based on the use of statistical methods, remains an important element in managing the quality of assembly of multi-element mass products on automatic rotor lines. The feature of continuous sampling control of the multi-element products completeness in the assembly process is its breaking sort, which excludes the possibility of returning component parts after sampling control to the process stream and leads to a decrease in the actual productivity of the assembly equipment. Therefore, the use of statistical procedures for continuous sampling control of the multi-element products completeness when assembled on automatic rotor lines requires the use of such sampling plans that ensure a minimum size of control samples. Comparison of the values of the limit of the average output defect level for the continuous sampling plan (CSP) and for the automated continuous sampling plan (ACSP) shows the possibility of providing lower limit values for the average output defects level using the ACSP-1. Also, the average sample size when using the ACSP-1 plan is less than when using the CSP-1 plan. Thus, the application of statistical methods in the assembly quality management of multi-element products on automatic rotor lines, involving the use of proposed plans and methods for continuous selective control, will allow to automating sampling control procedures and the required level of quality of assembled products while minimizing sample size.

Measurements of environmental gamma-ray spectra using a multi-element TL dosemeter

International Nuclear Information System (INIS)

Furuta, Sadaaki; Boetter-Jensen, L.; Nielsen, S.P.

1986-12-01

A method to estimate the energy distribution and dose of environmental gamma radiation was developed using a multielement TL dosemeter. Experimentally obtained energy responses from a multi-element TL dosemeter with different kinds of filters were used to calculate the energy distribution and related dose by the SAND-II computer code. The code was originally developed to estimate the neutron flux using a multiple foil activation method. Measurements were made at several locations with the multi-element TL dosemeter and comparisons were made with results from a NaI(Tl) scintillation detector and a high-pressure ionization chamber. (author)

Solving the Einstein constraint equations on multi-block triangulations using finite element methods

Energy Technology Data Exchange (ETDEWEB)

Korobkin, Oleg; Pazos, Enrique [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Aksoylu, Burak [Center for Computation and Technology, Louisiana State University, Baton Rouge, LA 70803 (United States); Holst, Michael [Department of Mathematics, University of California at San Diego 9500 Gilman Drive La Jolla, CA 92093-0112 (United States); Tiglio, Manuel [Department of Physics, University of Maryland, College Park, MD 20742 (United States)

2009-07-21

In order to generate initial data for nonlinear relativistic simulations, one needs to solve the Einstein constraints, which can be cast into a coupled set of nonlinear elliptic equations. Here we present an approach for solving these equations on three-dimensional multi-block domains using finite element methods. We illustrate our approach on a simple example of Brill wave initial data, with the constraints reducing to a single linear elliptic equation for the conformal factor psi. We use quadratic Lagrange elements on semi-structured simplicial meshes, obtained by triangulation of multi-block grids. In the case of uniform refinement the scheme is superconvergent at most mesh vertices, due to local symmetry of the finite element basis with respect to local spatial inversions. We show that in the superconvergent case subsequent unstructured mesh refinements do not improve the quality of our initial data. As proof of concept that this approach is feasible for generating multi-block initial data in three dimensions, after constructing the initial data we evolve them in time using a high-order finite-differencing multi-block approach and extract the gravitational waves from the numerical solution.

Solving the Einstein constraint equations on multi-block triangulations using finite element methods

International Nuclear Information System (INIS)

Korobkin, Oleg; Pazos, Enrique; Aksoylu, Burak; Holst, Michael; Tiglio, Manuel

2009-01-01

In order to generate initial data for nonlinear relativistic simulations, one needs to solve the Einstein constraints, which can be cast into a coupled set of nonlinear elliptic equations. Here we present an approach for solving these equations on three-dimensional multi-block domains using finite element methods. We illustrate our approach on a simple example of Brill wave initial data, with the constraints reducing to a single linear elliptic equation for the conformal factor ψ. We use quadratic Lagrange elements on semi-structured simplicial meshes, obtained by triangulation of multi-block grids. In the case of uniform refinement the scheme is superconvergent at most mesh vertices, due to local symmetry of the finite element basis with respect to local spatial inversions. We show that in the superconvergent case subsequent unstructured mesh refinements do not improve the quality of our initial data. As proof of concept that this approach is feasible for generating multi-block initial data in three dimensions, after constructing the initial data we evolve them in time using a high-order finite-differencing multi-block approach and extract the gravitational waves from the numerical solution.

MULTI ELEMENT SI SENSOR WITH READOUT ASIC FOR EXAFS SPECTROSCOPY.

Energy Technology Data Exchange (ETDEWEB)

DE GERONIMO,G.; O CONNOR,P.; BEUTTENMULLER,R.H.; LI,Z.; KUCZEWSKI,A.J.; SIDDONS,D.P.

2002-09-09

Extended X-ray Absorption Fine Structure (EXAFS) experiments impose stringent requirements on a detection system, due to the need for processing ionizing events at a high rate, typically above of 10Mcps/cm{sup 2}, and with a high resolution, typically better than 300eV. The detection system here presented is being developed targeting these stringent requirements. It is the result of a cooperation between the Instrumentation Division and the National Synchrotron Light Source (NSLS) of the Brookhaven National Laboratory (BNL). The system is composed of a multi-element Si sensor with dedicated per pixel electronics. The combination of high rate, high resolution and moderate complexity makes this system attractive when compared to other multi-element solutions. In sections 2, 3 and 4 the sensor, the interconnect and the electronics are briefly described. Section 5 reports on the first experimental results.

Stacked white OLED having separate red, green and blue sub-elements

Energy Technology Data Exchange (ETDEWEB)

Forrest, Stephen; Qi, Xiangfei; Slootsky, Michael

2014-07-01

The present invention relates to efficient organic light emitting devices (OLEDs). The devices employ three emissive sub-elements, typically emitting red, green and blue, to sufficiently cover the visible spectrum. Thus, the devices may be white-emitting OLEDs, or WOLEDs. Each sub-element comprises at least one organic layer which is an emissive layer--i.e., the layer is capable of emitting light when a voltage is applied across the stacked device. The sub-elements are vertically stacked and are separated by charge generating layers. The charge-generating layers are layers that inject charge carriers into the adjacent layer(s) but do not have a direct external connection.

Studies of the source complex behaviour and of the ultrasound radiation of contact flexible multi-element transducers; Etudes du comportement complexe de source et du rayonnement ultrasonore des traducteurs multi-elements flexibles au contact

Energy Technology Data Exchange (ETDEWEB)

Amory, V

2007-12-15

This work deals with the ultrasonic nondestructive testing of parts with complex geometries using soft multi-element sensors. The different types of contact control configurations are presented first. Then, the difficulties encountered with conventional contact transducers are explained and the multi-element piezoelectric transducers technology, developed to meet these difficulties, is presented. The second chapter presents the results of finite-element calculations showing the complexity of a transducer in a condition of testing utilization. In a same configuration, the radiated far field calculated by finite-elements is compared to the measurement in order to validate the way the source behaviour is calculated. However, despite the efficiency of the finite-elements simulation, this tool is numerically too costly and cannot be used to optimize a full multi-element transducer. Therefore, a realistic source model is built and implemented in a radiation code based on high-frequency asymptotic approximations where only L and T volume waves are calculated. The incapacity of this model to reproduce the behaviour of T waves in some directions of propagation has led to give a particular attention to the fore-waves, neglected in the radiation calculation. Chapter 3 treats of the building of an exact radiation model taking into consideration the fore-waves contribution emitted by a contact transducer exerting a random space-time distribution constraint at the surface of the considered medium. A radiation model, based on the calculation of exact Green functions of the Lamb problem is proposed. The exact model is particularly interesting in the case of sensor geometries with a long length with respect to other dimensions (2D case). Field calculation results are shown for an element of the matrix network (3D case) and for a linear element (2D case). A study of different existing approached models is carried out as well. The last chapter presents some results of the field

Spectral response of multi-element silicon detectors

Energy Technology Data Exchange (ETDEWEB)

Ludewigt, B.A.; Rossington, C.S.; Chapman, K. [Univ. of California, Berkeley, CA (United States)

1997-04-01

Multi-element silicon strip detectors, in conjunction with integrated circuit pulse-processing electronics, offer an attractive alternative to conventional lithium-drifted silicon Si(Li) and high purity germanium detectors (HPGe) for high count rate, low noise synchrotron x-ray fluorescence applications. One of the major differences between the segmented Si detectors and the commercially available single-element Si(Li) or HPGe detectors is that hundreds of elements can be fabricated on a single Si substrate using standard silicon processing technologies. The segmentation of the detector substrate into many small elements results in very low noise performance at or near, room temperature, and the count rate of the detector is increased many-fold due to the multiplication in the total number of detectors. Traditionally, a single channel of detector with electronics can handle {approximately}100 kHz count rates while maintaining good energy resolution; the segmented detectors can operate at greater than MHz count rates merely due to the multiplication in the number of channels. One of the most critical aspects in the development of the segmented detectors is characterizing the charge sharing and charge loss that occur between the individual detector strips, and determining how these affect the spectral response of the detectors.

A framework for developing finite element codes for multi-disciplinary applications.

OpenAIRE

Dadvand, Pooyan

2007-01-01

The world of computing simulation has experienced great progresses in recent years and requires more exigent multidisciplinary challenges to satisfy the new upcoming demands. Increasing the importance of solving multi-disciplinary problems makes developers put more attention to these problems and deal with difficulties involved in developing software in this area. Conventional finite element codes have several difficulties in dealing with multi-disciplinary problems. Many of these codes are d...

Multi-element neutron activation analysis and solution of classification problems using multidimensional statistics

International Nuclear Information System (INIS)

Vaganov, P.A.; Kol'tsov, A.A.; Kulikov, V.D.; Mejer, V.A.

1983-01-01

The multi-element instrumental neutron activation analysis of samples of mountain rocks (sandstones, aleurolites and shales of one of gold deposits) is performed. The spectra of irradiated samples are measured by Ge(Li) detector of the volume of 35 mm 3 . The content of 22 chemical elements is determined in each sample. The results of analysis serve as reliable basis for multi-dimensional statistic information processing, they constitute the basis for the generalized characteristics of rocks which brings about the solution of classification problem for rocks of different deposits

On the optimity of separation cascade for a binary and a multi-component case

International Nuclear Information System (INIS)

Song, T.M.; Zeng, S.

2006-01-01

The optimity discussed in this article means minimum total interstage flow which is studied for two cases, a binary and a multi-component case, using direct numerical optimizations for countercurrent symmetric cascades with the concentrations of the target component specified in the .feed flow, the product and waste withdrawals In binary separation, the ideal cascade in which there are no mixing losses and whose stages are working under symmetric separation is the optimum cascade that has the minimum total flow However when the separation factor is large, there may not exist an ideal cascade for certain prescribed external parameters. Cascades are optimized numerically to minimize mixing losses and total flows, respectively The results are compared for the minimum mixing losses and the minimum total flow, and analyzed with theoretically derived formulas. For the multi-component case, satisfying the non-mixing condition is impossible. There is a counterpart of the binary ideal cascade named MARC which matches the abundance ratio at mixing points. An optimization example for a four-cornponent mixture separation cascade is analyzed with the first and the last components as the targets, respectively. The results show that MARC is not the optimum cascade for the separation of one certain isotope. The separation power of each stage in the optimized cascades is calculated using several different definitions, and the rationality of these definitions is discussed. The Q-iteration method is used to calculate the concentration distribution in both the binary and the multi-component cases. Ns-2 stage cuts out of the Ns stages of the cascade are the optimization variables in the optimization process and a combination of the simulated annealing and the Hooke-Jeeves method is applied as the optimization technique to find the minimum. (authors)

Electromagnetic separator for light and middle isotope elements; Separateur electromagnetique pour les isotopes d'elements legers et moyens

Energy Technology Data Exchange (ETDEWEB)

Bernas, R [Commissariat a l' Energie Atomique, Lab. du Fort de Chatillon, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1952-07-01

We describe a separator of isotope with a 60 deg magnetic sector that permits, thanks to a process of neutralization of the space charge, to use efficiently intense ion beams. The ion source for solid is essentially constituted by a discharge of hot cathode in a magnetic field and provides an ion beam focused of more than 10 mA. The result of the first separations (Zn, Sb, Hg) indicates that the isotopes of various elements can be obtained in quantities varying from 10 to 100 mg/24 hours. (author) [French] 0n decrit un separateur d'isotope a secteur magnetique de 60 deg qui permet, grace a un procede de neutralisation de la charge d'espace, d'utiliser efficacement des faisceaux d'ions intenses. La source d'ions pour solide est essentiellement constituee par une decharge a cathode chaude dans un champ magnetique et fournit un faisceau d'ion focalises de plus de 10 mA. Le resultat des premieres separations (Zn, Sb, Hg) indique que les isotopes de divers elements peuvent etre obtenus en quantites variant de 10 a 100 mg/24 heures. (auteur)

Studies on absorption coefficient near edge of multi elements

International Nuclear Information System (INIS)

Eisa, M.H.; Shen, H.; Yao, H.Y.; Mi, Y.; Zhou, Z.Y.; Hu, T.D.; Xie, Y.N.

2005-01-01

X-ray absorption near edge structure (XANES) was used to study the near edge mass-absorption coefficients of seven elements, such as, Ti, V, Fe, Co, Ni, Cu and Zn. It is well known that, on the near edge absorption of element, when incident X-ray a few eV change can make the absorption coefficient an order magnitude alteration. So that, there are only a few points mass-absorption coefficient at the near edge absorption and that always average value in published table. Our results showed a wide range of data, the total measured data of mass-absorption coefficient of the seven elements was about 505. The investigation confirmed that XANES is useful technique for multi-element absorption coefficient measurement. Details of experimental methods and results are given and discussed. The experimental work has been performed at Beijing Synchrotron Radiation Facility. The measured values were compared with the published data. Good agreement between experimental results and published data is obtained

Studies on absorption coefficient near edge of multi elements

Science.gov (United States)

Eisa, M. H.; Shen, H.; Yao, H. Y.; Mi, Y.; Zhou, Z. Y.; Hu, T. D.; Xie, Y. N.

2005-12-01

X-ray absorption near edge structure (XANES) was used to study the near edge mass-absorption coefficients of seven elements, such as, Ti, V, Fe, Co, Ni, Cu and Zn. It is well known that, on the near edge absorption of element, when incident X-ray a few eV change can make the absorption coefficient an order magnitude alteration. So that, there are only a few points mass-absorption coefficient at the near edge absorption and that always average value in published table. Our results showed a wide range of data, the total measured data of mass-absorption coefficient of the seven elements was about 505. The investigation confirmed that XANES is useful technique for multi-element absorption coefficient measurement. Details of experimental methods and results are given and discussed. The experimental work has been performed at Beijing Synchrotron Radiation Facility. The measured values were compared with the published data. Good agreement between experimental results and published data is obtained.

Separation of traces of traces of trans-plutonium elements in weight quantities of rare earths

International Nuclear Information System (INIS)

SORET, Christian

1969-08-01

The author reports the separation of trans-plutonium elements and their dosing in a mixture of fission products. In some situations dosing is performed on both rare earths and trans-plutonium elements. The chemical separation process is a chromatographic method of exchange on an anionic resin in concentrated lithium chloride. He proposes a brief overview of separation processes, describes the separation mechanism, and then reports preliminary studies of the influence of increasing quantities of rare earths and the influence of increasing heights of resin bed in order to determine the best conditions of separation. He describes the preparation of resin and of the column, the introduction of the fixing solution at the top of the column, the preparation of lithium chloride solutions. He presents the adjustment and measurement devices, and the calculation of the resin minimum volume. Results are then presented and discussed. The operation mode is addressed: devices, reagents, preparation techniques (preparation of lithium chloride solutions) [fr

Multi-Column Experimental Test Bed for Xe/Kr Separation

International Nuclear Information System (INIS)

Greenhalgh, Mitchell Randy; Garn, Troy Gerry; Welty, Amy Keil; Lyon, Kevin Lawrence; Watson, Tony Leroy

2015-01-01

Previous research studies have shown that INL-developed engineered form sorbents are capable of capturing both Kr and Xe from various composite gas streams. The previous experimental test bed provided single column testing for capacity evaluations over a broad temperature range. To advance research capabilities, the employment of an additional column to study selective capture of target species to provide a defined final gas composition for waste storage was warranted. The second column addition also allows for compositional analyses of the final gas product to provide for final storage determinations. The INL krypton capture system was modified by adding an additional adsorption column in order to create a multi-column test bed. The purpose of this modification was to investigate the separation of xenon from krypton supplied as a mixed gas feed. The extra column was placed in a Stirling Ultra-low Temperature Cooler, capable of controlling temperatures between 190 and 253K. Additional piping and valves were incorporated into the system to allow for a variety of flow path configurations. The new column was filled with the AgZ-PAN sorbent which was utilized as the capture medium for xenon while allowing the krypton to pass through. The xenon-free gas stream was then routed to the cryostat filled with the HZ-PAN sorbent to capture the krypton at 191K. Selectivities of xenon over krypton were determined using the new column to verify the system performance and to establish the operating conditions required for multi-column testing. Results of these evaluations verified that the system was operating as designed and also demonstrated that AgZ-PAN exhibits excellent selectivity for xenon over krypton in air at or near room temperature. Two separation tests were performed utilizing a feed gas consisting of 1000 ppmv xenon and 150 ppmv krypton with the balance being made up of air. The AgZ-PAN temperature was held at 295 or 253K while the HZ-PAN was held at 191K for both

Finite element method for radiation heat transfer in multi-dimensional graded index medium

International Nuclear Information System (INIS)

Liu, L.H.; Zhang, L.; Tan, H.P.

2006-01-01

In graded index medium, ray goes along a curved path determined by Fermat principle, and curved ray-tracing is very difficult and complex. To avoid the complicated and time-consuming computation of curved ray trajectories, a finite element method based on discrete ordinate equation is developed to solve the radiative transfer problem in a multi-dimensional semitransparent graded index medium. Two particular test problems of radiative transfer are taken as examples to verify this finite element method. The predicted dimensionless net radiative heat fluxes are determined by the proposed method and compared with the results obtained by finite volume method. The results show that the finite element method presented in this paper has a good accuracy in solving the multi-dimensional radiative transfer problem in semitransparent graded index medium

Hydrometallurgical separation of rare earth elements, cobalt and nickel from spent nickel-metal-hydride batteries

Science.gov (United States)

Rodrigues, Luiz Eduardo Oliveira Carmo; Mansur, Marcelo Borges

The separation of rare earth elements, cobalt and nickel from NiMH battery residues is evaluated in this paper. Analysis of the internal content of the NiMH batteries shows that nickel is the main metal present in the residue (around 50% in weight), as well as potassium (2.2-10.9%), cobalt (5.1-5.5%), rare earth elements (15.3-29.0%) and cadmium (2.8%). The presence of cadmium reveals that some Ni-Cd batteries are possibly labeled as NiMH ones. The leaching of nickel and cobalt from the NiMH battery powder with sulfuric acid is efficient; operating variables temperature and concentration of H 2O 2 has no significant effect for the conditions studied. A mixture of rare earth elements is separated by precipitation with NaOH. Finally, solvent extraction with D2EHPA (di-2-ethylhexyl phosphoric acid) followed by Cyanex 272 (bis-2,4,4-trimethylpentyl phosphinic acid) can separate cadmium, cobalt and nickel from the leach liquor. The effect of the main operating variables of both leaching and solvent extraction steps are discussed aiming to maximize metal separation for recycling purposes.

Development of a dry-mechanical graphite separation process and elimination of the separated carbon for the reprocessing of spherical HTR fuel elements

International Nuclear Information System (INIS)

Kronschnabel, H.

1982-01-01

Due to the C-14 distribution the separation of the particle-free outer region of the spherical HTR fuel element with subsequent solidification of the separated carbon makes it possible to reduce by half the remaining C-14 inventory in the inner particle region to be further treated. Separation of the particle-free outer region by a newly developed sphere-peeling milling machine, conditioning the graphite into compacts and in-situ cementation into a salt-mine are the basic elements of this head-end process variation. An annual cavern volume of approx. 2000 m 3 will be needed to ultimately store the graphite of the particle-free outer region, which corresponds to a reprocessing capacity of 50 GWsub(e) installed HTR power. The brush-disintegration of the remaining inner particle region and the resulting peel-brush-preparation are capable of separating 95% of the graphite without any heavy metal losses. With the mentioned reprocessing capacity an annual cavern volume of approx. 16.500 m 3 is required. (orig.) [de

Radiochemical neutron activation analysis based multi-elemental analysis of high purity gallium

International Nuclear Information System (INIS)

Tashimova, F.A.; Sadikov, I.I; Salimov, M.I.; Zinov'ev, V.G.

2006-01-01

Full text: Gallium is one of the widely used materials in semiconductor and optoelectronics industry. Gallium is used to produce infrared detectors, piezoelectric sensors, high- and low-temperature transistors for space and defense technology. One of the most important requirements for semiconductor materials of gallium compounds is an excessive high purity for layers and films. Information on impurities (type of an impurity, concentration, character of distribution) is important as for better understanding of the physical and chemical processes taking place in formed semiconductor structures and for the 'know-how' of devices on their basis. The object of this work is to develop radiochemical neutron activation technique for analysis of high purity gallium. Irradiation of 0.1 g of gallium sample in neutron flux of 5·10 13 cm -2 s -1 for 5 hours will result in induced activity of more than 10 8 Bq, due to 72 Ga radionuclide, half-life of which is 14.1 hours. Therefore to perform instrumental NAA of gallium long period (10 day) cooling is required, and high sensitive determination of elements producing short- and long-lived radionuclides (T 1/2 72 Ga. We have studied the behavior of gallium in extraction-chromatographic system 'TBP-HCl'. The experiments have shown that higher factor of distribution (D) and capacity on gallium can be achieved when 'TBP-4M HCl' system is used. However more than 10 trace elements have high D and thus they cannot be separated from 72 Ga. To resolve the problem and increase the number of separated trace elements we have used preliminary satisfaction of chromatographic column with tellurium, which has D higher than the most of elements in 'TBP-4M HCl' system and thus suppresses extraction of elements. Distribution profile of gallium along the column and elution curve of 25 trace elements have been measured. Chemical yields of separated elements measured by using radiotracers are more than 93%. On the basis of the carried out researches

WE-G-18C-07: Accelerated Water/fat Separation in MRI for Radiotherapy Planning Using Multi-Band Imaging Techniques

Energy Technology Data Exchange (ETDEWEB)

Crijns, S; Stemkens, B; Sbrizzi, A; Lagendijk, J; Berg, C van den; Andreychenko, A [UMC Utrecht, Utrecht, Utrecht (Netherlands)

2014-06-15

Purpose: Dixon sequences are used to characterize disease processes, obtain good fat or water separation in cases where fat suppression fails and to obtain pseudo-CT datasets. Dixon's method uses at least two images acquired with different echo times and thus requires prolonged acquisition times. To overcome associated problems (e.g., for DCE/cine-MRI), we propose to use a method for water/fat separation based on spectrally selective RF pulses. Methods: Two alternating RF pulses were used, that imposes a fat selective phase cycling over the phase encoding lines, which results in a spatial shift for fat in the reconstructed image, identical to that in CAIPIRINHA. Associated aliasing artefacts were resolved using the encoding power of a multi-element receiver array, analogous to SENSE. In vivo measurements were performed on a 1.5T clinical MR-scanner in a healthy volunteer's legs, using a four channel receiver coil. Gradient echo images were acquired with TE/TR = 2.3/4.7ms, flip angle 20°, FOV 45×22.5cm{sup 2}, matrix 480×216, slice thickness 5mm. Dixon images were acquired with TE,1/TE,2/TR=2.2/4.6/7ms. All image reconstructions were done in Matlab using the ReconFrame toolbox (Gyrotools, Zurich, CH). Results: RF pulse alternation yields a fat image offset from the water image. Hence the water and fat images fold over, which is resolved using in-plane SENSE reconstruction. Using the proposed technique, we achieved excellent water/fat separation comparable to Dixon images, while acquiring images at only one echo time. Conclusion: The proposed technique yields both inphase water and fat images at arbitrary echo times and requires only one measurement, thereby shortening the acquisition time by a factor 2. In future work the technique may be extended to a multi-band water/fat separation sequence that is able to achieve single point water/fat separation in multiple slices at once and hence yields higher speed-up factors.

Search for chemical separations of the element 106 homologues in HF and HF-HCl media

International Nuclear Information System (INIS)

Trubert, D.; Monroy-Guzman, F.; Hussonnois, M.; Brillard, L.; Le Naour, C.; Constantinescu, O.

1996-01-01

In order to study the chemical properties of element 263 106 in aqueous media, fast, efficient and reproducible chromatographic separations were tested on its assumed homologous: Mo, W and U. Corroborative static and dynamic off-line experiments have shown that after fixation of these three elements on anion-exchange resin in HF medium, selective elution could be achieved by using suitable concentration of HCl - HF and HCl solutions. Separations of short-lived W isotopes, produced through heavy ion irradiation were also performed on-line. (author). 27 refs., 14 figs

Alternative separation of exchange and correlation energies in multi-configuration range-separated density-functional theory.

Science.gov (United States)

Stoyanova, Alexandrina; Teale, Andrew M; Toulouse, Julien; Helgaker, Trygve; Fromager, Emmanuel

2013-10-07

The alternative separation of exchange and correlation energies proposed by Toulouse et al. [Theor. Chem. Acc. 114, 305 (2005)] is explored in the context of multi-configuration range-separated density-functional theory. The new decomposition of the short-range exchange-correlation energy relies on the auxiliary long-range interacting wavefunction rather than the Kohn-Sham (KS) determinant. The advantage, relative to the traditional KS decomposition, is that the wavefunction part of the energy is now computed with the regular (fully interacting) Hamiltonian. One potential drawback is that, because of double counting, the wavefunction used to compute the energy cannot be obtained by minimizing the energy expression with respect to the wavefunction parameters. The problem is overcome by using short-range optimized effective potentials (OEPs). The resulting combination of OEP techniques with wavefunction theory has been investigated in this work, at the Hartree-Fock (HF) and multi-configuration self-consistent-field (MCSCF) levels. In the HF case, an analytical expression for the energy gradient has been derived and implemented. Calculations have been performed within the short-range local density approximation on H2, N2, Li2, and H2O. Significant improvements in binding energies are obtained with the new decomposition of the short-range energy. The importance of optimizing the short-range OEP at the MCSCF level when static correlation becomes significant has also been demonstrated for H2, using a finite-difference gradient. The implementation of the analytical gradient for MCSCF wavefunctions is currently in progress.

Precombustion desulfurization using Microcel{trademark} and multi-gravity separator

Energy Technology Data Exchange (ETDEWEB)

Yoon, R.H.; Luttrell, G.H.; Venkatraman, P. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States)

1994-12-31

Studies conducted at the Center for Coal and Minerals Processing (CCMP) indicate that surface-based processes such as froth flotation are inefficient in removing pyrite from fine coal. This shortcoming has been attributed to the fact that pyrite can become hydrophobic under certain conditions and to the inability of flotation to reject middling particles. To overcome these deficiencies, a new processing scheme has been developed at CCMP which involved the use of the Microcel{trademark} flotation column in combination with a centrifugal flowing-film separator, called a Multi-Gravity Separator (MGS). The flotation column removes ash-forming minerals such as clay, while the MGS is effective in removing pyrite. Preliminary test data obtained with high-sulfur coals shows that this processing scheme can nearly double the pyritic sulfur rejection with little loss in clean coal yield. This article discusses the underlying principles of the new circuit and provides test results obtained using eastern U.S. coals.

Simultaneous multi-element analysis of some edible pulses using neutron activation analysis

International Nuclear Information System (INIS)

El-Sweify, F.H.; Metwally, E.; Abdel-Khalik, H.

2007-01-01

This paper comprises the application of instrumental neutron activation analysis (INAA) for multi-element determination in some edible pulse samples. These edible pulses are usually daily used in the Egyptian kitchen. These were: anise, cumin, coriander, caraway, black cumin, white kidney bean, lupine, lentil, chickpea, broad bean, peanut, almond, and fenugreek. The pulses have been analyzed as dehulled pulses, in the case of legume and oil pulses with simultaneous analysis of their respective skins. The determined elements were: Ce, Co, Cr, Cs, Eu, Fe, Hf, Rb, Sb, Sc, Sr, Th and Zn. The element content in the dehulled pulses and their respective skins has been compared. Some elements were major or minor elements where others were trace elements. Standard reference materials were used to assure quality control, accuracy and precision of the technique. (author)

Multi-element determination in environmental samples by mass spectrometric isotope dilution analysis using thermal ionization. Pt. 2

International Nuclear Information System (INIS)

Hilpert, K.; Waidmann, E.

1988-01-01

An analytical procedure for the multi-element analysis of the elements Fe, Ni, Cu, Zn, Ga, Rb, Sr, Cd, Ba, Tl, and Pb in pine needles by mass spectrometric isotope dilution analysis using thermal ionization has been reported in Part I of this paper. This procedure is now transferred to the non-vegetable material 'Oyster Tissue' (Standard Reference Material 1566, National Bureau of Standards, USA). By a modification of the analytical procedure, it was possible to determine Cr in this material in addition to the aforementioned elements. No concentrations are certified for the elements Ga, Ba and Tl analyzed in this work. The concentrations of the remaining elements obtained by the multi-element analysis agree well with those certified. (orig.)

Provenance Establishment of Stingless Bee Honey Using Multi-element Analysis in Combination with Chemometrics Techniques.

Science.gov (United States)

Shadan, Aidil Fahmi; Mahat, Naji A; Wan Ibrahim, Wan Aini; Ariffin, Zaiton; Ismail, Dzulkiflee

2018-01-01

As consumption of stingless bee honey has been gaining popularity in many countries including Malaysia, ability to identify accurately its geographical origin proves pertinent for investigating fraudulent activities for consumer protection. Because a chemical signature can be location-specific, multi-element distribution patterns may prove useful for provenancing such product. Using the inductively coupled-plasma optical emission spectrometer as well as principal component analysis (PCA) and linear discriminant analysis (LDA), the distributions of multi-elements in stingless bee honey collected at four different geographical locations (North, West, East, and South) in Johor, Malaysia, were investigated. While cross-validation using PCA demonstrated 87.0% correct classification rate, the same was improved (96.2%) with the use of LDA, indicating that discrimination was possible for the different geographical regions. Therefore, utilization of multi-element analysis coupled with chemometrics techniques for assigning the provenance of stingless bee honeys for forensic applications is supported. © 2017 American Academy of Forensic Sciences.

Multi-component separation and analysis of bat echolocation calls.

Science.gov (United States)

DiCecco, John; Gaudette, Jason E; Simmons, James A

2013-01-01

The vast majority of animal vocalizations contain multiple frequency modulated (FM) components with varying amounts of non-linear modulation and harmonic instability. This is especially true of biosonar sounds where precise time-frequency templates are essential for neural information processing of echoes. Understanding the dynamic waveform design by bats and other echolocating animals may help to improve the efficacy of man-made sonar through biomimetic design. Bats are known to adapt their call structure based on the echolocation task, proximity to nearby objects, and density of acoustic clutter. To interpret the significance of these changes, a method was developed for component separation and analysis of biosonar waveforms. Techniques for imaging in the time-frequency plane are typically limited due to the uncertainty principle and interference cross terms. This problem is addressed by extending the use of the fractional Fourier transform to isolate each non-linear component for separate analysis. Once separated, empirical mode decomposition can be used to further examine each component. The Hilbert transform may then successfully extract detailed time-frequency information from each isolated component. This multi-component analysis method is applied to the sonar signals of four species of bats recorded in-flight by radiotelemetry along with a comparison of other common time-frequency representations.

Optimal acid digestion for multi-element analysis of different waste matrices

DEFF Research Database (Denmark)

Götze, Ramona; Astrup, Thomas Fruergaard

of the distinct waste materials and recyclables. The purpose of this study is to evaluate the performance of different standardized microwave assisted acid digestion methods on waste samples and subsequent multi-element analysis. Six acid digestion methods were applied on a Paper & Cardboard and Composite waste...

The use of tetracycline as complexing agent for the separation of interfering elements during uranium activation analysis

International Nuclear Information System (INIS)

Petrauskas, R.

1984-01-01

A method was developed for uranium separation, when its determination could not be performed by non-destructive neutron activation analysis due to the presence of interfering elements. Th, Zn, Na, Ta, Fe, W, Mo, Ag and the lanthanides were considered interferents because some of these elements, via (n, γ) reactions, form the same radioisotopes produced in the fission of 235 U, or radioisotopes that emit gamma-rays with energies close to the ones emitted by 239 Np or by the fission products of 235 U. Besides they could form radioisotopes whose Compton continuum makes difficult the detection of the gamma-rays of 239 Np and the fission products of 235 U. The separation method is based on the extraction of uranium from the interfering elements using a solution of tetracycline in benzyl alcohol. Adequate conditions for the separation were studied and extraction curves of uranium and interferents were obtained separately and in the presence of a solution of uranium ore from the IAEA. Separation of uranium from Na, Ag and Zn was achieved with a single extraction operation and by controlling the pH of the aqueous phase. Diethylenetriaminepentaacetic acid was used as masking agent for uranium separation from Fe, Th and lanthanides. For other elements, the separation was partial, meaning that about 11% of W, 32% of Mo and 5% of Ta were extracted together with uranium after two extraction operations (extraction and washing). Chemical separation presented a recovery of 97% for uranium. After separation an aliquot of organic phase containing uranium was irradiated for uranium and isotopic ratio 235 U/ 238 U determinations. This method was applied in the analysis of the following ores: standard S-7 (pitchblende) provided by IAEA, monazite and an ore called 'goianita' from the state of Goias (GO, Brazil). The accuracy and precision of results were discussed, and the isotopic ratio results indicated that the ores analysed present an isotopic abundance of natural uranium. (Author

Multi-element proportional counter for radiation protection measurements

International Nuclear Information System (INIS)

Kliauga, P.; Rossi, H.H.; Johnson, G.

1988-01-01

This article discusses design modifications of a multi-element proportional counter. The original counter exhibited poor resolution, as measured by the width of the event-size spectrum for low-energy photons. It was also suspected that the field inside each volume was not sufficiently symmetric. Results of the modifications showed that a dramatic improvement in resolution could be obtained in the chamber with tissue-equivalent septa if their potentials were adjusted to obtain optimal resolution. The full width at half maximum then approached, although it did not equal, that of a standard spherical counter

Studies of the source complex behaviour and of the ultrasound radiation of contact flexible multi-element transducers

International Nuclear Information System (INIS)

Amory, V.

2007-12-01

This work deals with the ultrasonic nondestructive testing of parts with complex geometries using soft multi-element sensors. The different types of contact control configurations are presented first. Then, the difficulties encountered with conventional contact transducers are explained and the multi-element piezoelectric transducers technology, developed to meet these difficulties, is presented. The second chapter presents the results of finite-element calculations showing the complexity of a transducer in a condition of testing utilization. In a same configuration, the radiated far field calculated by finite-elements is compared to the measurement in order to validate the way the source behaviour is calculated. However, despite the efficiency of the finite-elements simulation, this tool is numerically too costly and cannot be used to optimize a full multi-element transducer. Therefore, a realistic source model is built and implemented in a radiation code based on high-frequency asymptotic approximations where only L and T volume waves are calculated. The incapacity of this model to reproduce the behaviour of T waves in some directions of propagation has led to give a particular attention to the fore-waves, neglected in the radiation calculation. Chapter 3 treats of the building of an exact radiation model taking into consideration the fore-waves contribution emitted by a contact transducer exerting a random space-time distribution constraint at the surface of the considered medium. A radiation model, based on the calculation of exact Green functions of the Lamb problem is proposed. The exact model is particularly interesting in the case of sensor geometries with a long length with respect to other dimensions (2D case). Field calculation results are shown for an element of the matrix network (3D case) and for a linear element (2D case). A study of different existing approached models is carried out as well. The last chapter presents some results of the field

An optimization on strontium separation model for fission products (inactive trace elements) using artificial neural networks

International Nuclear Information System (INIS)

Moosavi, K.; Setayeshi, S.; Maragheh, M.Gh.; Ahmadi, S.J.; Kardan, M.R.; Banaem, L.M.

2009-01-01

In this study, an experimental design using artificial neural networks for an optimization on the strontium separation model for fission products (inactive trace elements) is investigated. The goal is to optimize the separation parameters to achieve maximum amount of strontium that is separated from the fission products. The result of the optimization method causes a proper purity of Strontium-89 that was separated from the fission products. It is also shown that ANN may be establish a method to optimize the separation model.

Separation of interfering elements in the neutron activation analysis of lanthanides in geological materials

International Nuclear Information System (INIS)

Saiki, M.

1988-01-01

A chemical procedure has been developed for the separation of U, Th, Fe, Sc, Na,Ta, and Mo which interfere in the neutron activation analysis of the lanthanide elements in geological materials. This procedure is based on the solvent extraction of interferents using a solution of tetracycline in benzyl alcohol. The lanthanide elements remaining in the aqueous phase are coprecipitated on calcium oxalate or ferric hydroxide for irradiation and subsequent determination by gamma ray spectrometry. The chemical separation procedure was applied in the analysis of lanthanides in two international geological reference materials GSP-1 (USGS), GS-N (CRPG) and in the analysis of a volcanic rock from Pocos de Caldas, MG, Brazil. The sensitivities for all the lanthanides were determined. (author) [pt

Precision and Accuracy of k0-NAA Method for Analysis of Multi Elements in Reference Samples

International Nuclear Information System (INIS)

Sri-Wardani

2004-01-01

Accuracy and precision of k 0 -NAA method could determine in the analysis of multi elements contained in reference samples. The analyzed results of multi elements in SRM 1633b sample were obtained with optimum results in bias of 20% but it is in a good accuracy and precision. The analyzed results of As, Cd and Zn in CCQM-P29 rice flour sample were obtained with very good result in bias of 0.5 - 5.6%. (author)

A multi-element cosmological model with a complex space-time topology

Science.gov (United States)

Kardashev, N. S.; Lipatova, L. N.; Novikov, I. D.; Shatskiy, A. A.

2015-02-01

Wormhole models with a complex topology having one entrance and two exits into the same space-time of another universe are considered, as well as models with two entrances from the same space-time and one exit to another universe. These models are used to build a model of a multi-sheeted universe (a multi-element model of the "Multiverse") with a complex topology. Spherical symmetry is assumed in all the models. A Reissner-Norström black-hole model having no singularity beyond the horizon is constructed. The strength of the central singularity of the black hole is analyzed.

Multi-Element Composition of Honey as a Suitable Tool for Its Authenticity Analysis

Directory of Open Access Journals (Sweden)

Oroian Mircea

2015-06-01

Full Text Available The aim of this study was to evaluate the composition of 36 honey samples of 4 different botanical origins (acacia, sun flower, tilia and honeydew from the North East region of Romania. An inductively coupled plasma-mass spectrometry (ICP-MS method was used to determine 27 elements in honey (Ag, Al, As, Ba, Be, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, K, Li, Mg, Mn, Na, Ni, Pb, Rb, Se, Sr, Tl, U, V and Zn. We would like to achieve the following goal: to demonstrate that the qualitative and quantitative multi-element composition determination of honey can be used as a suitable tool to classify honey according to its botanical origin. The principal component analysis allowed the reduction of the 27 variables to 2 principal components which explained 74% of the total variance. The dominant elements which were strongly associated with the principal component were K, Mg and Ca. Discriminant models obtained for each kind of botanical honey confirmed that the differentiation of honeys according to their botanical origin was mainly based on multi-element composition. A correct classification of all samples was achieved with the exception of 11.1% of honeydew honeys.

Influence of elution rate on the efficiency of chromatographic separation process of rare earth and transplutonium elements

International Nuclear Information System (INIS)

Peshkov, A.S.; Chuveleva, Eh.A.; Nazarov, P.P.; Rybakov, S.Yu.

1990-01-01

Applicability of finely dispersed sulfocationites of the KU-2-8 MD grade for the separation of radionuclides of rare earth and transplutonium element separation by the method of replacing complexing chromatography (RCC) has been investigated. Using as an example separation of neodymium-praseodymium, yttrium-europium by the RCC method, using nitriloacetic (1) and diethylenetriaminepentaacetic (2) acid solutions as eluent, the dependence of the element separation of ficiency on elution rate is shown. It is found that when using solution 1 as eluent, the value of the height equivalent to theoretical plate depends on elution rate much less, than in case of solution 2. The conclusion is made that for 1 the main contribution to the blurring of the areas is made by transcolumn effect, and for 2 -by transcolumn and transpartial effects

Separation and accumulation of acitinides with the aid of a phosphoric acid polymer

International Nuclear Information System (INIS)

Novikov, A.; Geckeler, K.E.

1993-01-01

A new method for the separation and enrichment of actinides based on the use of polymer reagents is presented, in this study, poly(ethyleneimine methylphosphonic acid) was used for the interaction with actinide ions in the homogeneous phase. In conjunction with membrane filtration this reagent allows both the separation and the enrichment of actinides from dilute solutions. The retention profiles for the series of actinides U(VI), Np(V), Pu(IV), Am(III), Cm(III), Cf(III) were investigated at different pH. Retention differences between 0% and 100% were found depending on the actinide element and pH. Thus, these elements can be separated and enriched form aqueous solutions of binary or multi-component mixtures. (orig.)

Finite Macro-Element Mesh Deformation in a Structured Multi-Block Navier-Stokes Code

Science.gov (United States)

Bartels, Robert E.

2005-01-01

A mesh deformation scheme is developed for a structured multi-block Navier-Stokes code consisting of two steps. The first step is a finite element solution of either user defined or automatically generated macro-elements. Macro-elements are hexagonal finite elements created from a subset of points from the full mesh. When assembled, the finite element system spans the complete flow domain. Macro-element moduli vary according to the distance to the nearest surface, resulting in extremely stiff elements near a moving surface and very pliable elements away from boundaries. Solution of the finite element system for the imposed boundary deflections generally produces smoothly varying nodal deflections. The manner in which distance to the nearest surface has been found to critically influence the quality of the element deformation. The second step is a transfinite interpolation which distributes the macro-element nodal deflections to the remaining fluid mesh points. The scheme is demonstrated for several two-dimensional applications.

Numerical Study Of Flue Gas Flow In A Multi Cyclone Separator

OpenAIRE

Ganga Reddy C; Umesh Kuppuraj

2015-01-01

The removal of harmful particulate matter from power plant flue gas is of critical importance to the environment and its inhabitants. The present work illustrates the use of multi-cyclone separators to remove the particulate matter from the bulk of the gas exhausted to the atmosphere. The method has potential to replace conventional systems like electrostatic precipitator due to inherent low power requirement and low maintenance. A parametric model may be employed to design the sy...

MicroCT parameters for multi material elements assessment

Energy Technology Data Exchange (ETDEWEB)

Araújo, Olga M.O. de; Machado, Alessandra S.; Santos, Thaís M.P. dos; Ferreira, Cintia G.; Lopes, Ricardo T., E-mail: olgaufrjlin@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Bastos, Jaqueline Silva [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), São Paulo, SP (Brazil)

2017-07-01

Microtomography is a non-destructive testing technique for quantitative and qualitative analysis. The investigation of multi material elements with great difference of density can result in artifacts that degrade image quality depending on combination of additional filter. The aim of this study is the selection of parameters most appropriate for analysis of bone tissue with metallic implant. The results show the simulation with MCNPX code for the distribution of energy without additional filter, with use of aluminum, copper and brass filters and their respective reconstructed images showing the importance of the choice of these parameters in image acquisition process on computed microtomography. (author)

Multi-Column Xe/Kr Separation with AgZ-PAN and HZ-PAN

International Nuclear Information System (INIS)

Greenhalgh, Mitchell Randy; Garn, Troy Gerry; Welty, Amy Keil; Watson, Tony Leroy

2016-01-01

Previous multi-column xenon/krypton separation tests have demonstrated the capability of separating xenon from krypton in a mixed gas feed stream. The results of this initial testing with AgZ-PAN and HZ-PAN indicated that an excellent separation of xenon from krypton could be achieved. Building upon these initial results, a series of additional multi-column testing were performed in FY-16. The purpose of this testing was to scale up the sorbent beds, test a different composition of feed gas and attempt to improve the accuracy of the analysis of the individual capture columns' compositions. Two Stirling coolers were installed in series to perform this testing. The use of the coolers instead of the cryostat provided two desired improvements, 1) removal of the large dilution due to the internal volume of the cryostat adsorption chamber, and 2) ability to increase the sorbent bed size for scale-up. The AgZ-PAN sorbent, due to its xenon selectivity, was loaded in the first column to capture the xenon while allowing the krypton to flow through and be routed to a second column containing the HZ-PAN for capture and analysis. The gases captured on both columns were sampled with evacuated sample bombs and subsequently analyzed via GC-MS for both krypton and xenon. The results of these tests can be used to develop the scope of future testing and analysis using this test bed for demonstrating the capture and separation of xenon and krypton using sorbents, for demonstrating desorption and regeneration of the sorbents, and for determining compositions of the desorbed gases. They indicate a need for future desorption studies in order to better quantify co-adsorbed species and final krypton purity.

Multi-Column Xe/Kr Separation with AgZ-PAN and HZ-PAN

Energy Technology Data Exchange (ETDEWEB)

Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States); Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony Leroy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-08-01

Previous multi-column xenon/krypton separation tests have demonstrated the capability of separating xenon from krypton in a mixed gas feed stream. The results of this initial testing with AgZ-PAN and HZ-PAN indicated that an excellent separation of xenon from krypton could be achieved. Building upon these initial results, a series of additional multi-column testing were performed in FY-16. The purpose of this testing was to scale up the sorbent beds, test a different composition of feed gas and attempt to improve the accuracy of the analysis of the individual capture columns’ compositions. Two Stirling coolers were installed in series to perform this testing. The use of the coolers instead of the cryostat provided two desired improvements, 1) removal of the large dilution due to the internal volume of the cryostat adsorption chamber, and 2) ability to increase the sorbent bed size for scale-up. The AgZ-PAN sorbent, due to its xenon selectivity, was loaded in the first column to capture the xenon while allowing the krypton to flow through and be routed to a second column containing the HZ-PAN for capture and analysis. The gases captured on both columns were sampled with evacuated sample bombs and subsequently analyzed via GC-MS for both krypton and xenon. The results of these tests can be used to develop the scope of future testing and analysis using this test bed for demonstrating the capture and separation of xenon and krypton using sorbents, for demonstrating desorption and regeneration of the sorbents, and for determining compositions of the desorbed gases. They indicate a need for future desorption studies in order to better quantify co-adsorbed species and final krypton purity.

Recovery and separation of rare-earth elements, barium, and strontium from bastnasite with sulfuric acid

International Nuclear Information System (INIS)

Eisele, J.A.; Bauer, D.J.

1974-01-01

A bench-scale investigation was made of a concentrated H 2 SO 4 reaction for recovering and separating rare earth elements, barium, and strontium from a bastnaesite ore and byproduct. Barium and strontium were dissolved in the concentrated acid and precipitated as a mixed product by water dilution. Separation of strontium from barium was effected by reaction with Na 2 CO 3 solution, followed by a dilute acid leach of the SrCO 3 formed. After removing the barium and strontium from bastnaesite ore, the rare-earth elements were roasted to water-soluble sulfates. The rare earth sulfate solution was subsequently processed by solvent extraction to produce rare-earth oxides low in lead and magnesium. (U.S.)

Advances in the hydrometallurgical separation techniques of high purity rare earth elements

International Nuclear Information System (INIS)

Vijayalakshmi, R.; Kain, V.

2017-01-01

Rare Earths are a series of 15 chemically similar elements that occur together in monazite mineral found in the beach sands of Kerala, Tamil Nadu and Orissa. The rare earth elements (REE) are becoming increasingly strategically important considering their essential role in permanent magnets such as, SmCo_5, Sm_2Co_1_7 and Nd_2Fe_1_4B, phosphors for LED screens and lamps, rechargeable nickel metal hydride batteries and catalysts and other green applications. The increasing popularity of hybrid and electric cars, wind turbines and compact fluorescent lamps is causing an increase in the demand and price of REE. The European Commission considers the REE as the most critical raw materials group, with the highest supply risk. According to the medium-term criticality matrix of the U.S. Department of Energy (DOE), the five most critical REE are neodymium (Nd), europium (Eu), terbium (Tb), dysprosium (Dy) and yttrium (Y). China is presently producing more than 90% of all rare earths, although they possess less than 405 of the proven reserves. Due to large and increasing domestic demands, China tightened its REE export quota from 2012 onwards. These export quotas caused serious problems for REE users outside of China. Fortunately India is blessed with large resources of rare earths in the form of monazite found in the beach sands of Kerala, Tamil Nadu and Orissa. Indian Rare Earths Limited at Aluva near Kochi produces mainly mixed rare earths chloride and till recent past exporting to USA, UK, France, Japan, etc. They have revived their rare earth separation plant to meet the in-house demands of the strategic, defense and nuclear industry. This paper discusses the recent advances made in hydrometallurgical separation techniques based on solvent extraction technique, ion-exchange resins, hollow fibre membrane extractor, solvent encapsulated polymeric beads, etc for the production of high purity rare earth elements from both primary (Monazite, xenotime) and secondary sources

Fully automated dissolution and separation methods for inductively coupled plasma atomic emission spectrometry rock analysis. Application to the determination of rare earth elements

International Nuclear Information System (INIS)

Govindaraju, K.; Mevelle, G.

1987-01-01

In rock analysis laboratories, sample preparation is a serious problem, or even an enormous bottleneck. Because this laboratory is production-oriented, this problem was attacked by automating progressively, different steps in rock analysis for major, minor and trace elements. This effort has been considerably eased by the fact that all sample preparation schemes in this laboratory for the past three decades have been based on an initial lithium borate fusion of rock samples and all analytical methods based on multi-element atomic emission spectrometry, with switch-over from solid analysis by arc/spark excitation to solution analysis by plasma excitation in 1974. The sample preparation steps which have been automated are: weighing of samples and fluxes, lithium borate fusion, dissolution and dilution of fusion products and ion-exchange separation of difficult trace elements such as rare earth elements (REE). During 1985 and 1986, these different unit operations have been assembled together as peripheral units in the form of a workstation, called LabRobStation. A travelling robot is the master of LabRobStation, with all peripheral units at its reach in 10 m 2 workspace. As an example of real application, the automated determination of REE, based on more than 8000 samples analysed during 1982 and 1986, is presented. (author)

MEGHNAD – A multi element detector array for heavy ion collision ...

Indian Academy of Sciences (India)

When heavy ion beam available from such machines fall on a target and undergo collision, very rich and often pristine fields of research open up. In order to carry on such activities, we have taken up a project to build a multi element gamma, heavy ion and neutron array of detectors (MEGHNAD) to detect and study the ...

Hybrid Direct and Iterative Solver with Library of Multi-criteria Optimal Orderings for h Adaptive Finite Element Method Computations

KAUST Repository

AbouEisha, Hassan M.

2016-06-02

In this paper we present a multi-criteria optimization of element partition trees and resulting orderings for multi-frontal solver algorithms executed for two dimensional h adaptive finite element method. In particular, the problem of optimal ordering of elimination of rows in the sparse matrices resulting from adaptive finite element method computations is reduced to the problem of finding of optimal element partition trees. Given a two dimensional h refined mesh, we find all optimal element partition trees by using the dynamic programming approach. An element partition tree defines a prescribed order of elimination of degrees of freedom over the mesh. We utilize three different metrics to estimate the quality of the element partition tree. As the first criterion we consider the number of floating point operations(FLOPs) performed by the multi-frontal solver. As the second criterion we consider the number of memory transfers (MEMOPS) performed by the multi-frontal solver algorithm. As the third criterion we consider memory usage (NONZEROS) of the multi-frontal direct solver. We show the optimization results for FLOPs vs MEMOPS as well as for the execution time estimated as FLOPs+100MEMOPS vs NONZEROS. We obtain Pareto fronts with multiple optimal trees, for each mesh, and for each refinement level. We generate a library of optimal elimination trees for small grids with local singularities. We also propose an algorithm that for a given large mesh with identified local sub-grids, each one with local singularity. We compute Schur complements over the sub-grids using the optimal trees from the library, and we submit the sequence of Schur complements into the iterative solver ILUPCG.

Morphing the feature-based multi-blocks of normative/healthy vertebral geometries to scoliosis vertebral geometries: development of personalized finite element models.

Science.gov (United States)

Hadagali, Prasannaah; Peters, James R; Balasubramanian, Sriram

2018-03-12

Personalized Finite Element (FE) models and hexahedral elements are preferred for biomechanical investigations. Feature-based multi-block methods are used to develop anatomically accurate personalized FE models with hexahedral mesh. It is tedious to manually construct multi-blocks for large number of geometries on an individual basis to develop personalized FE models. Mesh-morphing method mitigates the aforementioned tediousness in meshing personalized geometries every time, but leads to element warping and loss of geometrical data. Such issues increase in magnitude when normative spine FE model is morphed to scoliosis-affected spinal geometry. The only way to bypass the issue of hex-mesh distortion or loss of geometry as a result of morphing is to rely on manually constructing the multi-blocks for scoliosis-affected spine geometry of each individual, which is time intensive. A method to semi-automate the construction of multi-blocks on the geometry of scoliosis vertebrae from the existing multi-blocks of normative vertebrae is demonstrated in this paper. High-quality hexahedral elements were generated on the scoliosis vertebrae from the morphed multi-blocks of normative vertebrae. Time taken was 3 months to construct the multi-blocks for normative spine and less than a day for scoliosis. Efforts taken to construct multi-blocks on personalized scoliosis spinal geometries are significantly reduced by morphing existing multi-blocks.

Multi-elemental analysis of aqueous geological samples by inductively coupled plasma-optical emission spectrometry

Science.gov (United States)

Todorov, Todor I.; Wolf, Ruth E.; Adams, Monique

2014-01-01

Typically, 27 major, minor, and trace elements are determined in natural waters, acid mine drainage, extraction fluids, and leachates of geological and environmental samples by inductively coupled plasma-optical emission spectrometry (ICP-OES). At the discretion of the analyst, additional elements may be determined after suitable method modifications and performance data are established. Samples are preserved in 1–2 percent nitric acid (HNO3) at sample collection or as soon as possible after collection. The aqueous samples are aspirated into the ICP-OES discharge, where the elemental emission signals are measured simultaneously for 27 elements. Calibration is performed with a series of matrix-matched, multi-element solution standards.

A multi-stage oil-water-separating process design for the sea oil spill recovery robot

Science.gov (United States)

Zhang, Min-ge; Wu, Jian-guo; Lin, Xinhua; Wang, Xiao-ming

2018-03-01

Oil spill have the most common pollution to the marine ecological environment. In the late stage of physical method recovery, because of the thin oil and the strong sea breeze, the recovery vessels has low efficiency and high energy consumption. This paper develops a multi-stage oil-water-separating process carried by the sea oil spill recovery robot in severe conditions. This design consists of three separation process, among which both the first and third process adopt corrugated sheets horizontal oil-water separator, while the second is hydraulic rotary breaker. This design also equiptment with rectifier and cyclone separator and other important components. This process has high flexibility and high recovery efficiency. The implement effect is significant.

Separation of transuranium elements from high-level waste by extraction with diisodecyl phosphoric acid

International Nuclear Information System (INIS)

Morita, Y.; Kubota, M.; Tani, S.

1991-01-01

Separation of transuranic elements (TRU) by extraction with diisodecyl phosphoric acid (DIDPA) has been studied to develop a partitioning process for high-level waste (HLW). In the present study, experiments of counter-current continuous extraction and back-extraction using a miniature mixer-settler were carried out to find the optimum process condition for the separation of Np initially in the pentavalent state and to examine the extraction behaviors of fission and corrosion products. (J.P.N.)

Electrodialytic separation of alkali-element ions with the aid of ion-exchange membranes

International Nuclear Information System (INIS)

Gurskii, V.S.; Moskvin, L.N.

1988-01-01

Electrodialytic separation of ions bearing charges of the same sign with the aid of ion-exchange membranes has been examined in the literature in relation to the so-called ideal membranes, which do not exhibit selectivity with respect to one ion type in ion exchange. It has been shown that separation on such membranes is effective only for counterions differing in size of charge. A matter of greater importance from the practical standpoint is the possibility of using electrodialysis for separating ions bearing like charges and having similar properties, including ionic forms of isotopes of the same element. In this paper they report a comparative study of ion separation, with reference to the Cs-Na pair, by electrodialysis through various types of cation-exchange membranes. Changes of the solution concentration in the cathode compartment were monitored by measurement of 22 Na and 137 Cs activities

Extended automated separation techniques in destructive neutron activation analysis; application to various biological materials, including human tissues and blood

International Nuclear Information System (INIS)

Tjioe, P.S.; Goeij, J.J.M. de; Houtman, J.P.W.

1976-09-01

Neutron activation analysis may be performed as a multi-element and low-level technique for many important trace elements in biological materials, provided that post-irradiation chemical separations are applied. This paper describes a chemical separation consisting of automated procedures for destruction, distillation, and anion-chromatography. The system developed enables the determination of 14 trace elements in biological materials, viz. antimony, arsenic, bromine, cadmium, chromium, cobalt, copper, gold, iron, mercury, molybdenum, nickel, selenium, and zinc. The aspects of sample preparation, neutron irradiation, gamma-spectrum evaluation, and blank-value contribution are also discussed

Use of reference materials for quality control of elemental analysis by neutron activation with radiochemical separation

International Nuclear Information System (INIS)

Woittiez, J.R.W.

1990-01-01

This paper describes the use of certified reference materials to monitor the long-term quality of radiochemical separations. The practical limitations which determine the actual design of the quality control are discussed. The hypothesis that the high yield of the radiochemical separation will be constant with time has been checked and validated for the elements Zn, Fe, Co, Cd, Mo and to a lesser extent for W and Th using NBS SRM 1577A, BCR CRM 274 and IAEA RM A-11. This validation could not be made for the elements Cr, Au, and Ag. Especially for Cr there is a serious lack of appropiate certified reference materials. (orig.)

Design and Fabrication of High Gain Multi-element Multi-segment Quarter-sector Cylindrical Dielectric Resonator Antenna

Science.gov (United States)

Ranjan, Pinku; Gangwar, Ravi Kumar

2017-12-01

A novel design and analysis of quarter cylindrical dielectric resonator antenna (q-CDRA) with multi-element and multi-segment (MEMS) approach has been presented. The MEMS q-CDRA has been designed by splitting four identical quarters from a solid cylinder and then multi-segmentation approach has been utilized to design q-CDRA. The proposed antenna has been designed for enhancement in bandwidth as well as for high gain. For bandwidth enhancement, multi-segmentation method has been explained for the selection of dielectric constant of materials. The performance of the proposed MEMS q-CDRA has been demonstrated with design guideline of MEMS approach. To validate the antenna performance, three segments q-CDRA has been fabricated and analyzed practically. The simulated results have been in good agreement with measured one. The MEMS q-CDRA has wide impedance bandwidth (|S11|≤-10 dB) of 133.8 % with monopole-like radiation pattern. The proposed MEMS q-CDRA has been operating at TM01δ mode with the measured gain of 6.65 dBi and minimum gain of 4.5 dBi in entire operating frequency band (5.1-13.7 GHz). The proposed MEMS q-CDRA may find appropriate applications in WiMAX and WLAN band.

Optimization conditions for the separation of rare earth elements, americium, curium and cesium with HPLC technique

International Nuclear Information System (INIS)

Goutelard, F.; Caussignac, C.; Brennetot, R.; Stadelmann, G.; Gautier, C.

2009-01-01

In order to validate the neutronic code calculations used in the nuclear field, it is necessary to quantify the isotopic composition of the nuclear irradiated fuels with high precision and accuracy. A separation step whose objective is to isolate the elements of interest in a fraction as pure as possible, is performed before mass spectrometry detection (MC-ICP-MS, TIMS), in order to eliminate isobaric interferences. In a first step, uranium and plutonium are separated from the fission products by ion exchange chromatography. Then, fission products are separated by high performance liquid chromatography (HPLC). A gradient separation with a silica sulphonated support as stationary phase and hydroxy-methyl butyric acid (HMB) as eluent solution provides a good degree of separation of the rare earth elements, Am, Cm and Cs. But, for a same manufacturer, the rate of sulphonated groups is variable from one column to another for a given production batch. For every replacement of column, it is necessary to adjust the separation conditions. Furthermore, the high radioactivity of the samples injected damages the stationary phase, dragging a regular renewal of the columns. The goal of this study is to determine the optimal separation conditions with a minimum of tests in order to limit the time assigned to this operation. A first Doehlert experimental design with pH and HMB concentration as variables has been implemented to optimize Gd, Eu separation, in isocratic initial conditions. A second one has been tested in order to separate the higher lanthanides and to fix the final conditions of the gradient separation. A last set of tests has been performed to characterize the cesium behaviour. Finally, the gradient conditions have been adjusted in order to perform the full separation of lanthanides, Cs, Am and Cm with nuclear facilities. (author)

Development of radiochemical separation method for determination of toxic elements in biological samples

International Nuclear Information System (INIS)

Maihara, V.A.; Vasconcellos, M.B.A.; Favaro, D.I.T.; Armelin, M.J.A.

1990-01-01

In order to determine Hg, Sb, As and Se in biological materials by neutron activation analysis, a radiochemical separation was developed. The chemical separation procedure used was based on the digestion of the irradiated sample in a mixture of H NO 3 and H 2 SO 4 in a teflon bomb, at 130 0 C for 1 to 4 hours. After the dissolution of organic matter, Hg and Sb were retained by a Dowex 2-X8 resin column in 6 M HCl. The effluent was passed through a TDO, tin dioxide column which retains As and Se in 3 M HCl medium. Radioactive tracers of these elements were used to determine the yields of the separation process. Certified reference materials were analyzed to check the precision and accuracy of the method. (author)

Development of a radiochemical separation method for toxic elements determination from biologic samples

International Nuclear Information System (INIS)

Malhara, V.A.; Vasconcellos, M.B.A.; Favaro, D.I.T.; Armelin, M.J.A.

1990-01-01

In order to determine Hg, Sb, As and Se in biological materials by neutron activation analysis, a radiochemical separation was developed. The chemical separation procedure used was based on the digestion of the irradiated sample in a mixture of HNO 3 and H 2 SO 4 in a teflon bomb, at 130 0 C for 1 to 4 hours. After the dissolution of organic matter, Hg and Sb were retained by a Dowex 2-XB resin column in 6M HCI. The efluent was passed through a TDO, tin dioxide column which retains As and Se in 3M HCI medium. Radioactive tracers of these elements were used to determine the yields of the separation process. Certified reference materials were analyzed to check the precision and accuracy of the method. (author)

Rare earths: critical elements for various applications and challenges in their separation

International Nuclear Information System (INIS)

Singh, D.K.; Chakravartty, J.K.

2015-01-01

High purity rare earths oxides, metal and alloys find wide applications in high tech area such as nuclear energy, permanent magnets, materials for storing hydrogen, phosphors, laser, etc. Rare earths consists a group of 15 elements from La to Lu in the periodic table and it also includes Sc and Y. Due to similar chemical nature owing to common oxidation state of +3, rare earths are very difficult to separate from each other. They have very low separation factors with acidic extractants like D2EHPA and EHEHPA and hence require large number of stages in various cascade of extraction process. Monazite (a source of rare earths, thorium and uranium) is processed at IREL to separate rare earths from thorium and uranium. The rare earths are fractionated into three groups namely light rare earths (LRE), middle rare earths (MRE) and heavy rare earths (HRE) by solvent extraction method employing EHEHPA as extractant

Multi-element analysis of emeralds and associated rocks by k0 neutron activation analysis

International Nuclear Information System (INIS)

Acharya, R.N.; Mondal, R.K.; Burte, P.P.; Nair, A.G.C.; Reddy, N.B.Y.; Reddy, L.K.; Reddy, A.V.R.; Manohar, S.B.

2000-01-01

Multi-element analysis was carried out in natural emeralds, their associated rocks and one sample of beryl obtained from Rajasthan, India. The concentrations of 21 elements were assayed by Instrumental Neutron Activation Analysis using the k 0 method (k 0 INAA method) and high-resolution gamma ray spectrometry. The data reveal the segregation of some elements from associated (trapped and host) rocks to the mineral beryl forming the gemstones. A reference rock standard of the US Geological Survey (USGS BCR-1) was also analysed as a control of the method

Parameter Optimization of Multi-Element Synthetic Aperture Imaging Systems

Directory of Open Access Journals (Sweden)

Vera Behar

2007-03-01

Full Text Available In conventional ultrasound imaging systems with phased arrays, the further improvement of lateral resolution requires enlarging of the number of array elements that in turn increases both, the complexity and the cost, of imaging systems. Multi-element synthetic aperture focusing (MSAF systems are a very good alternative to conventional systems with phased arrays. The benefit of the synthetic aperture is in reduction of the system complexity, cost and acquisition time. In a MSAF system considered in the paper, a group of elements transmit and receive signals simultaneously, and the transmit beam is defocused to emulate a single element response. The echo received at each element of a receive sub-aperture is recorded in the computer memory. The process of transmission/reception is repeated for all positions of a transmit sub-aperture. All the data recordings associated with each corresponding pair "transmit-receive sub-aperture" are then focused synthetically producing a low-resolution image. The final high-resolution image is formed by summing of the all low-resolution images associated with transmit/receive sub-apertures. A problem of parameter optimization of a MSAF system is considered in this paper. The quality of imaging (lateral resolution and contrast is expressed in terms of the beam characteristics - beam width and side lobe level. The comparison between the MSAF system described in the paper and an equivalent conventional phased array system shows that the MSAF system acquires images of equivalent quality much faster using only a small part of the power per image.

Detailed finite element method modeling of evaporating multi-component droplets

Energy Technology Data Exchange (ETDEWEB)

Diddens, Christian, E-mail: C.Diddens@tue.nl

2017-07-01

The evaporation of sessile multi-component droplets is modeled with an axisymmetic finite element method. The model comprises the coupled processes of mixture evaporation, multi-component flow with composition-dependent fluid properties and thermal effects. Based on representative examples of water–glycerol and water–ethanol droplets, regular and chaotic examples of solutal Marangoni flows are discussed. Furthermore, the relevance of the substrate thickness for the evaporative cooling of volatile binary mixture droplets is pointed out. It is shown how the evaporation of the more volatile component can drastically decrease the interface temperature, so that ambient vapor of the less volatile component condenses on the droplet. Finally, results of this model are compared with corresponding results of a lubrication theory model, showing that the application of lubrication theory can cause considerable errors even for moderate contact angles of 40°. - Graphical abstract:.

Operational trials of single- and multi-element CR-39 dosemeters for the DIDO and PLUTO reactors at the Harwell Laboratory

International Nuclear Information System (INIS)

Gallacher, G.G.; Perks, C.A.

1993-01-01

Single- and multi-element CR-39 dosemeters, developed at the Harwell Laboratory, and a commercially available multi-element CR-39 dosemeter (obtained from Track Analysis Systems Ltd), were evaluated for their potential as neutron dosemeters for personnel working at Harwell Laboratory's research reactors. Owing to the angular dependence of the CR-39 (processed using electrochemical etching), the single-element dosemeter was found to be impractical. Consequently, a multi-element dosemeter was developed, which consisted of a cube of side 36 mm with CR-39 elements (also processed using electrochemical etching) attached to each of the sides. Although this dosemeter was technically suitable for this type of dosimetry, it was considered to be unacceptably bulky in personnel trials. The commercially available CR-39 dosemeter tested was much smaller (the CR-39 was only chemically etched) and this was considered to be acceptable as a personnel dosemeter. In addition, trials with personnel working at active handling glove boxes indicated that single-element dosemeters might be adequate, but further work would be needed to verify this. (author)

Separation and Simultaneous Determination of 14 Fungicides with the Combination of Multi-Analyte Methods and HPLC Detection

Energy Technology Data Exchange (ETDEWEB)

Canping, Pan [Department of Applied Chemistry, China Agricultural University, Beijing (China)

2009-07-15

The separation and simultaneous HPLC-MS determination for a series of fungicide products is reported. Multi-analyte methods were applied on a Chromolith RP-18e monolithic column having low resistance and enabling high flow rates and short analysis time at very good separation power. Details and analytical conditions are described with chromatograms illustrating the results and work done. (author)

Rolling Process Modeling Report: Finite-Element Prediction of Roll Separating Force and Rolling Defects

Energy Technology Data Exchange (ETDEWEB)

Soulami, Ayoub [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Paxton, Dean M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Burkes, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2014-04-23

Pacific Northwest National Laboratory (PNNL) has been investigating manufacturing processes for the uranium-10% molybdenum (U-10Mo) alloy plate-type fuel for the U.S. high-performance research reactors. This work supports the Convert Program of the U.S. Department of Energy’s National Nuclear Security Administration (DOE/NNSA) Global Threat Reduction Initiative. This report documents modeling results of PNNL’s efforts to perform finite-element simulations to predict roll separating forces and rolling defects. Simulations were performed using a finite-element model developed using the commercial code LS-Dyna. Simulations of the hot rolling of U-10Mo coupons encapsulated in low-carbon steel have been conducted following two different schedules. Model predictions of the roll-separation force and roll-pack thicknesses at different stages of the rolling process were compared with experimental measurements. This report discusses various attributes of the rolled coupons revealed by the model (e.g., dog-boning and thickness non-uniformity).

An Assessment of the Icing Blade and the SEA Multi-Element Sensor for Liquid Water Content Calibration of the NASA GRC Icing Research Tunnel

Science.gov (United States)

Steen, Laura E.; Ide, Robert F.; Van Zante, Judith Foss

2017-01-01

The Icing Research Tunnel at NASA Glenn has recently switched to from using the Icing Blade to using the SEA Multi-Element Sensor (also known as the multi-wire) for its calibration of cloud liquid water content. In order to perform this transition, tests were completed to compare the Multi-Element Sensor to the Icing Blade, particularly with respect to liquid water content, airspeed, and drop size. The two instruments were found to compare well for the majority of Appendix C conditions. However, it was discovered that the Icing Blade under-measures when the conditions approach the Ludlam Limit. This paper also describes data processing procedures for the Multi-Element Sensor in the IRT, including collection efficiency corrections, mounting underneath a splitter plate, and correcting for a jump in the compensation wire power. Further data is presented to describe the repeatability of the IRT with the Multi-Element sensor, health-monitoring checks for the instrument, and a sensing-element configuration comparison.

The gas filled separator as a separation method to detect transuranic elements

International Nuclear Information System (INIS)

Ninov, V.

1992-08-01

The mass spectrometer NASE (NAchSEparator) built as a post-separator and located behind the velocity filter SHIP at the GSI in Darmstadt, was taken into operation as a gas-filled separator, and its separation properties for fusion products from heavy ion reactions were studied. Chapter 2 describes the principle of separation in a gas-filled magnet. The technical specifications of the separator, the detectors and the setup of detection electronics are outlined in chapter 3. The studies of separation properties are described in chapter 4, and chapter 5 deals with preliminary applications of the gas-filled separator to detect isotopes poor in neutrons, with an atomic number Z = 92, 93. Chapter 6 is concerned with preliminary tests to detect heavy nuclei with an atomic number Z > = 100 by means of light radiation and actinide targets. The experimental results of comparative measurements between the velocity filter SHIP and the gas-filled separator are pointed out in chapter 7, and future application possibilities of gas-filled separators for synthesis of heaviest nuclei through asymmetric reactions are discussed. (orig./BBR) [de

Separation of soft and collinear infrared limits of QCD squared matrix elements

CERN Document Server

Nagy, Zoltan; Trócsányi, Z L; Trocsanyi, Zoltan; Somogyi, Gabor; Trocsanyi, Zoltan

2007-01-01

We present a simple way of separating the overlap between the soft and collinear factorization formulae of QCD squared matrix elements. We check its validity explicitly for single and double unresolved emissions of tree-level processes. The new method makes possible the definition of helicity-dependent subtraction terms for regularizing the real contributions in computing radiative corrections to QCD jet cross sections. This implies application of Monte Carlo helicity summation in computing higher order corrections.

Magnetically assisted chemical separation (MACS) process: Preparation and optimization of particles for removal of transuranic elements

International Nuclear Information System (INIS)

Nunez, L.; Kaminski, M.; Bradley, C.; Buchholz, B.A.; Aase, S.B.; Tuazon, H.E.; Vandegrift, G.F.; Landsberger, S.

1995-05-01

The Magnetically Assisted Chemical Separation (MACS) process combines the selectivity afforded by solvent extractants with magnetic separation by using specially coated magnetic particles to provide a more efficient chemical separation of transuranic (TRU) elements, other radionuclides, and heavy metals from waste streams. Development of the MACS process uses chemical and physical techniques to elucidate the properties of particle coatings and the extent of radiolytic and chemical damage to the particles, and to optimize the stages of loading, extraction, and particle regeneration. This report describes the development of a separation process for TRU elements from various high-level waste streams. Polymer-coated ferromagnetic particles with an adsorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted with tributyl phosphate (TBP) were evaluated for use in the separation and recovery of americium and plutonium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles, which can then be recovered from the solution by using a magnet. The partition coefficients were larger than those expected based on liquid[liquid extractions, and the extraction proceeded with rapid kinetics. Extractants were stripped from the particles with alcohols and 400-fold volume reductions were achieved. Particles were more sensitive to acid hydrolysis than to radiolysis. Overall, the optimization of a suitable NMCS particle for TRU separation was achieved under simulant conditions, and a MACS unit is currently being designed for an in-lab demonstration

Separation of rare earth elements in monazite sand by anion exchange resin (pt. II)

International Nuclear Information System (INIS)

Cha, K.W.; Lee, J.H.; Yoon, S.H.; Ha, Y.G.

1980-01-01

An anion exchange method for separating Y, La, Ce, Pr, and Nd element in monazaites and into enriched fractions has been developed. The complexed rare earth ions with EDTA at pH 8.4 passed through the resin column of the various size and eluted with 0.0301 M EDTA as eluent at flow rate of 1 ml/min and 2 ml/min. The result of separation is good in the high column length rather than the low on using the resin of the same amount and the volume of eluent required in eluting all the rare earths at 2 ml/min flow rare is larger than that at 1 ml/min and the result of separation obtained here is unsatisfactory. (author)

AC power flow importance measures considering multi-element failures

International Nuclear Information System (INIS)

Li, Jian; Dueñas-Osorio, Leonardo; Chen, Changkun; Shi, Congling

2017-01-01

Quantifying the criticality of individual components of power systems is essential for overall reliability and management. This paper proposes an AC-based power flow element importance measure, while considering multi-element failures. The measure relies on a proposed AC-based cascading failure model, which captures branch overflow, bus load shedding, and branch failures, via AC power flow and optimal power flow analyses. Taking the IEEE 30, 57 and 118-bus power systems as case studies, we find that N-3 analyses are sufficient to measure the importance of a bus or branch. It is observed that for a substation bus, its importance is statistically proportional to its power demand, but this trend is not observed for power plant buses. While comparing with other reliability, functionality, and topology-based importance measures popular today, we find that a DC power flow model, although better correlated with the benchmark AC model as a whole, still fails to locate some critical elements. This is due to the focus of DC-based models on real power that ignores reactive power. The proposed importance measure is aimed to inform decision makers about key components in complex systems, while improving cascading failure prevention, system backup setting, and overall resilience. - Highlights: • We propose a novel importance measure based on joint failures and AC power flow. • A cascading failure model considers both AC power flow and optimal power flow. • We find that N-3 analyses are sufficient to measure the importance of an element. • Power demand impacts the importance of substations but less so that of generators. • DC models fail to identify some key elements, despite correlating with AC models.

Experimental investigation in separating the heavy metal elements of refuse incineration fly ashes by using molten iron

Energy Technology Data Exchange (ETDEWEB)

Yang, J. [Chongqing Univ., Chongqing (China)]|[CPI-Yuanda Environmental-protection Engineering Co. Ltd., Chongqing (China); Liu, Q.; Dong, L. [Chongqing Univ., Chongqing (China); Du, Y. [CPI-Yuanda Environmental-protection Engineering Co. Ltd., Chongqing (China)

2008-07-01

One of the main waste treatment methods in the world for municipal solid waste (MSW) is incineration. It is effective in toxic substance destruction, waste volume reduction, and energy recovery. Some chemical substances are accumulated during incineration, most notably lead, zinc, chromium and cadmium, as well as other heavy metals. Untreated fly ash disposed in landfills can pollute the soil, surface water and groundwater because of the high levels of hazardous heavy metals and high salt concentration that can be leached out. This paper presented an experiment that melt-separated the heavy metal elements from fly ash generated during refuse incineration. Molted iron, was used as resolvent to dissolve the heavy metal elements in it. The paper described the materials and methods as well as the results of the study. It was concluded that using molted iron to separate the heavy metal elements from MSW incineration fly ash was feasible. The removal ratio of the main heavy metal elements was above 80 per cent, and some of it was above 99 per cent. 5 refs., 7 tabs., 1 fig.

US Participation in the Solar Orbiter Multi Element Telescope for Imaging and Spectroscopy (METIS) Project

Data.gov (United States)

National Aeronautics and Space Administration — The Multi Element Telescope for Imaging and Spectroscopy, METIS, investigation has been conceived to perform off-limb and near-Sun coronagraphy and is motivated by...

The evaluation of multi-element personal dosemeters using the linear programming method

International Nuclear Information System (INIS)

Kragh, P.; Ambrosi, P.; Boehm, J.; Hilgers, G.

1996-01-01

Multi-element dosemeters are frequently used in individual monitoring. Each element can be regarded as an individual dosemeter with its own individual dose measurement value. In general, the individual dose values of one dosemeter vary according to the exposure conditions, i. e. the energy and angle of incidence of the radiation. The (final) dose measurement value of the personal dosemeter is calculated from the individual dose values by means of an evaluation algorithm. The best possible dose value, i.e. that of the smallest systematic (type B) uncertainty if the exposure conditions are changed in the dosemeter's rated range of use, is obtained by the method of linear programming. (author)

Multi-elemental imaging of paraffin-embedded human samples by laser-induced breakdown spectroscopy

Science.gov (United States)

Moncayo, S.; Trichard, F.; Busser, B.; Sabatier-Vincent, M.; Pelascini, F.; Pinel, N.; Templier, I.; Charles, J.; Sancey, L.; Motto-Ros, V.

2017-07-01

Chemical elements play central roles for physiological homeostasis in human cells, and their dysregulation might lead to a certain number of pathologies. Novel imaging techniques that improve the work of pathologists for tissue analysis and diagnostics are continuously sought. We report the use of Laser-Induced Breakdown Spectroscopy (LIBS) to perform multi-elemental images of human paraffin-embedded skin samples on the entire biopsy scale in a complementary and compatible way with microscope histopathological examination. A specific instrumental configuration is proposed in order to detect most of the elements of medical interest (i.e. P, Al, Mg, Na, Zn, Si, Fe, and Cu). As an example of medical application, we selected and analysed skin biopsies, including healthy skin tissue, cutaneous metastasis of melanoma, Merkel-cell carcinoma and squamous cell carcinoma. Clear distinctions in the distribution of chemical elements are observed from the different samples investigated. This study demonstrates the high complementarity of LIBS elemental imaging with conventional histopathology, opening new opportunities for any medical application involving metals.

Multi-element analysis of emeralds and associated rocks by k{sub 0} neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Acharya, R.N.; Mondal, R.K.; Burte, P.P.; Nair, A.G.C.; Reddy, N.B.Y.; Reddy, L.K.; Reddy, A.V.R.; Manohar, S.B

2000-12-15

Multi-element analysis was carried out in natural emeralds, their associated rocks and one sample of beryl obtained from Rajasthan, India. The concentrations of 21 elements were assayed by Instrumental Neutron Activation Analysis using the k{sub 0} method (k{sub 0} INAA method) and high-resolution gamma ray spectrometry. The data reveal the segregation of some elements from associated (trapped and host) rocks to the mineral beryl forming the gemstones. A reference rock standard of the US Geological Survey (USGS BCR-1) was also analysed as a control of the method.

Temporal stability of otolith elemental fingerprints discriminates among lagoon nursery habitats

Science.gov (United States)

Tournois, Jennifer; Ferraton, Franck; Velez, Laure; McKenzie, David J.; Aliaume, Catherine; Mercier, Lény; Darnaude, Audrey M.

2013-10-01

The chemical composition of fish otoliths reflects that of the water masses that they inhabit. Otolith elemental compositions can, therefore, be used as natural tags to discriminate among habitats. However, for retrospective habitat identification to be valid and reliable for any adult, irrespective of its age, significant differences in environmental conditions, and therefore otolith signatures, must be temporally stable within each habitat, otherwise connectivity studies have to be carried out by matching year-classes to the corresponding annual fingerprints. This study investigated how various different combinations of chemical elements in otoliths could distinguish, over three separate years, between four coastal lagoon habitats used annually as nurseries by gilthead sea bream (Sparus aurata L.) in the Gulf of Lions (NW Mediterranean). A series of nine elements were measured in otoliths of 301 S. aurata juveniles collected in the four lagoons in 2008, 2010 and 2011. Percentages of correct re-assignment of juveniles to their lagoon of origin were calculated with the Random Forest classification method, considering every possible combination of elements. This revealed both spatial and temporal variations in accuracy of habitat identification, with correct re-assignment to each lagoon ranging from 44 to 99% depending on the year and the lagoon. There were also annual differences in the combination of elements that provided the best discrimination among the lagoons. Despite this, when the data from the three years were pooled, a combination of eight elements (B, Ba, Cu, Li, Mg, Rb, Sr and Y) provided greater than 70% correct re-assignment to each single lagoon, with a multi-annual global accuracy of 79%. When considering the years separately, discrimination accuracy with these elemental fingerprints was above 90% for 2008 and 2010. It decreased to 61% in 2011, when unusually heavy rainfall occurred, which presumably reduced chemical differences among several of the

Predictions of wet natural gases condensation rates via multi-component and multi-phase simulation of supersonic separators

International Nuclear Information System (INIS)

Shooshtari, Seyed Heydar Rajaee; Shahsavand, Akbar

2014-01-01

Proper correction of water and heavy hydrocarbon dew points of sweet natural gases is essential from various technical and economical standpoints. Supersonic separators (3S) are proved to be capable of achieving these tasks with maximum reliability and minimal expenses. The majority of the previous articles have focused on the flow behavior of pure fluids across a 3S unit. Multicomponent fluid flow inside 3S accompanied with condensation phenomenon will drastically increase the complexity of the simulation process. We tackle this issue by considering a proper combination of fundamental governing equations and phase equilibrium calculations to predict various operating conditions and composition profiles across two multi-component and multi-phase 3S units. Various Iranian sweet gases are used as real case studies to demonstrate the importance of 3S unit practical applications. Simulation results clearly illustrate the effectiveness of 3S units for faithful dehydration of various natural gases, while successfully controlling its dew point, suitable for any practical applications. Conventional HYSYS simulation software is used to validate the simulation results

Boundary element numerical method for the electric field generated by oblique multi-needle electrodes

Institute of Scientific and Technical Information of China (English)

LIU FuPing; WANG AnLing; WANG AnXuan; CAO YueZu; CHEN Qiang; YANG ChangChun

2009-01-01

According to the electric potential of oblique multi-needle electrodes (OMNE) in biological tissue, the discrete equations based on the indetermination linear current density were established by the boundary element integral equations (BEIE). The non-uniform distribution of the current flowing from multi-needle electrodes to conductive biological tissues was imaged by solving a set of linear equa-tions. Then, the electric field and potential generated by OMNE in biological tissues at any point may be determined through the boundary element method (BEM). The time of program running and stability of computing method are examined by an example. It demonstrates that the algorithm possesses a quick speed and the steady computed results. It means that this method has an important referenced significance for computing the field and the potential generated by OMNE in bio-tissue, which is a fast, effective and accurate computing method.

Radiochemical separation and ICP-AES determination of some common metallic elements in ThO2 matrix

International Nuclear Information System (INIS)

Adya, V.C.; Hon, N.S.; Bangia, T.R.; Sastry, M.D.; Iyer, R.H.

1997-01-01

Radioactive tracer and also ICP-AES studies have been carried out to determine Al, Cd, Ca, Cr, Co, Cu, Mn, Mo and Pd in ThO 2 matrix after chemical separation. Di-2-ethyl-hexyl phosphoric acid/xylene/HNO 3 extraction system was used for quantitative separation of thorium. The recovery of elements as determined by tracers and ICP-AES was found to be quantitative within experimental error. (author). 3 refs., 1 tab

Design and Wind Tunnel Testing of a Thick, Multi-Element High-Lift Airfoil

DEFF Research Database (Denmark)

Zahle, Frederik; Gaunaa, Mac; Sørensen, Niels N.

2012-01-01

In this work a 2D CFD solver has been used to optimize the shape of a leading edge slat with a chord length of 30% of the main airfoil which was 40% thick. The airfoil configuration was subsequently tested in a wind tunnel and compared to numerical predictions. The multi-element airfoil was predi...

Efficiency Evaluation of Food Waste Materials for the Removal of Metals and Metalloids from Complex Multi-Element Solutions.

Science.gov (United States)

Massimi, Lorenzo; Giuliano, Antonella; Astolfi, Maria Luisa; Congedo, Rossana; Masotti, Andrea; Canepari, Silvia

2018-02-26

Recent studies have shown the potential of food waste materials as low cost adsorbents for the removal of heavy metals and toxic elements from wastewater. However, the adsorption experiments have been performed in heterogeneous conditions, consequently it is difficult to compare the efficiency of the individual adsorbents. In this study, the adsorption capacities of 12 food waste materials were evaluated by comparing the adsorbents' efficiency for the removal of 23 elements from complex multi-element solutions, maintaining homogeneous experimental conditions. The examined materials resulted to be extremely efficient for the adsorption of many elements from synthetic multi-element solutions as well as from a heavy metal wastewater. The 12 adsorbent surfaces were analyzed by Fourier transform infrared spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements. By multivariate statistical computations of the obtained data, the 12 food waste materials were grouped in five clusters characterized by different elements' removal efficiency which resulted to be in correlation with the specific adsorbents' chemical structures. Banana peel, watermelon peel and grape waste resulted the least selective and the most efficient food waste materials for the removal of most of the elements.

A novel network of chaotic elements and its application in multi-valued associative memory

International Nuclear Information System (INIS)

Xiu Chunbo; Liu Xiangdong; Tang Yunyu; Zhang Yuhe

2004-01-01

We give a novel chaotic element model whose activation function composed of Gauss and Sigmoid function. It is shown that the model may exhibit a complex dynamic behavior. The most significant bifurcation processes, leading to chaos, are investigated through the computation of the Lyapunov exponents. Based on this model, we propose a novel network of chaotic elements, which can be applied in associative memory, and then investigate its dynamic behavior. It is worth noting that multi-valued associative memory can also be realized by this network

Multi-elemental profile of some Brazilian make-up products by instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

Dalmazio, Ilza; Menezes, Maria Angela de B.C., E-mail: id@cdtn.b, E-mail: menezes@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Reator e Tecnicas Analiticas. Lab. de Ativacao Neutronica

2011-07-01

Recent works have shown that analysis in cosmetics and beauty products from the European and Asian markets indicate the presence of U, Th and rare earths besides other trace elements. Considering these previous findings and health issues, it would be valuable to obtain information on elements in cosmetics available in the Brazilian market. The purpose of this study was to acquire a multi-elemental profile of some Brazilian make-up products of diverse brands. Samples of eye shadow, liquid base, facial concealer, lipstick, and compact face powder were analyzed applying neutron activation analysis, k{sub 0}-standardization method at CDTN/CNEN, using the TRIGA Mark I IPR-R1 research reactor. Concentrations of more than 30 elements in samples are presented and it was found elements included in Brazilian National Health Surveillance Agency prohibitive list, rare earths, Th and U in a minimum of two cosmetic samples. (author)

Multi-elemental profile of some Brazilian make-up products by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Dalmazio, Ilza; Menezes, Maria Angela de B.C.

2011-01-01

Recent works have shown that analysis in cosmetics and beauty products from the European and Asian markets indicate the presence of U, Th and rare earths besides other trace elements. Considering these previous findings and health issues, it would be valuable to obtain information on elements in cosmetics available in the Brazilian market. The purpose of this study was to acquire a multi-elemental profile of some Brazilian make-up products of diverse brands. Samples of eye shadow, liquid base, facial concealer, lipstick, and compact face powder were analyzed applying neutron activation analysis, k 0 -standardization method at CDTN/CNEN, using the TRIGA Mark I IPR-R1 research reactor. Concentrations of more than 30 elements in samples are presented and it was found elements included in Brazilian National Health Surveillance Agency prohibitive list, rare earths, Th and U in a minimum of two cosmetic samples. (author)

Study on the use of neutron activation analysis within a new separation method in order to determine element traces in sea water

International Nuclear Information System (INIS)

Amman, K.

1982-01-01

Starting from the problematic situation of neutron activation analysis of sea salt it is outlined, that an early separation of disturbing nuclides of chief components will considerably increase the number of elements which can be determined by NAA of sea salt. Referring to this, a new separation method is presented which allows the selective separation of chief activities with the high decontamination factors required. For 21 elements limits of detection achieved by this method are compared with the average content of sea water. (orig.) [de

Current extraction and separation of uranium, thorium and rare earths elements from monazite leach solution using organophosphorous extractants

International Nuclear Information System (INIS)

Biswas, Sujoy; Rupawate, V.H.; Hareendran, K.N.; Roy, S.B.

2014-01-01

A new process based on solvent extraction has been developed for separation of uranium, thorium and rare earths from monazite leach solution using organophosphorous extractants. The Thorium cake coming from monazite source was dissolved in HNO 3 medium in presence of trace amount of HF for feed preparation. The separation of U(VI) was carried out by liquid-liquid extraction using tris-2-ethyl hexyl phosphoric acid (TEHP) in dodecane leaving thorium and rare earths elements in the raffinate. The thorium from raffinate was selectively extracted using 1M tri iso amyl phosphate (TiAP) in dodecane in organic phase leaving all rare earths elements in aqueous solution. The uranium and thorium from organic medium was quantitatively stripped using 0.05 M HNO 3 counter current mode. Results indicate the quantitative separation of uranium, thorium and rare earths from thorium cake (monazite source) using organophosphorous extractant in counter current mode

Fixation and separation of the elements thorium and uranium using anion exchange resins in nitrate solution; Fixation et separation des elements thorium et uranium par les resines echangeuses d'anions en milieu nitrate

Energy Technology Data Exchange (ETDEWEB)

Korgaonkar, V. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-10-01

The exchange of thorium and uranium between a strong base anion resin and a mixed water + ethanol solvent containing nitrate ions is studied. It is assumed that in the resin the thorium and uranium are fixed in the form of the complexes Th(NO{sub 3}){sub 6}{sup 2-} and UO{sub 2}(NO{sub 3}){sub 4}{sup 2-} in solution these elements are present in the form of complexes having the general formula: Th(NO{sub 3}){sub 6-n}{sup n-2} and UO{sub 2}(NO{sub 3}){sub 4-n}{sup n-2} It has been possible to deduce a law for the changes in the partition functions of thorium and uranium as a function of the concentrations of the various species in solution and of the complexing ion NO{sub 3}. From this has been deduced the optimum operational conditions for separating a mixture of these two elements. Finally, in these conditions, the influence of a few interfering ions has been studied: Ba, Bi, Ce, La, Mo, Pb, Zr. The method proposed can be used either as a preparation, or for the dosage of thorium by a quantitative separation. (author) [French] On etudie l'echange du thorium et de l'uranium entre une resine anion base forte et un solvant mixte eau + ethanol charge en ions nitrates. On a suppose que, dans la resine, le thorium et l'uranium sont fixes sous forme de complexes Th(NO{sub 3}){sub 6}{sup 2-} et UO{sub 2}(NO{sub 3}){sub 4}{sup 2-} en solution, ces elements sont engages dans des complexes de formule generale: Th(NO{sub 3}){sub 6-n}{sup n-2} and UO{sub 2}(NO{sub 3}){sub 4-n}{sup n-2} On a pu degager une loi de variation des coefficients de partage du thorium et de l'uranium en fonction des concentrations des diverses especes en solution et de l'anion complexant NO{sub 3}{sup -}. On en a deduit les conditions operatoires optimales necessaires pour separer les deux elements a partir de leurs melanges. Enfin, dans ces conditions, on a etudie l'influence de quelques elements genants: Ba, Bi, Ce, La, Mo, Pb, Zr. La methode preconisee peut etre

Multi-element analysis of crude-oil samples by 14.6 MeV neutron activation

International Nuclear Information System (INIS)

Cam, N.F.; Cigeroglu, F.; Erduran, M.N.

1997-01-01

The instrumental neutron activation technique, using the SAMEST T-400 neutron generator with 14.6 MeV neutrons produced from 3 H(d,n) 4 He reaction, is demonstrated for multi-element analysis of Saudi-Arabian crude-oil samples. The system parameters for the absolute method (e.g., the counting solid-angle, intrinsic efficiency of the γ-ray detector, effective neutron flux, activation cross sections, etc.)were determined and the results of elemental concentrations were presented with the corrections for all possible interferences having been carefully considered. (author)

Efficiency Evaluation of Food Waste Materials for the Removal of Metals and Metalloids from Complex Multi-Element Solutions

Science.gov (United States)

Giuliano, Antonella; Astolfi, Maria Luisa; Congedo, Rossana; Masotti, Andrea; Canepari, Silvia

2018-01-01

Recent studies have shown the potential of food waste materials as low cost adsorbents for the removal of heavy metals and toxic elements from wastewater. However, the adsorption experiments have been performed in heterogeneous conditions, consequently it is difficult to compare the efficiency of the individual adsorbents. In this study, the adsorption capacities of 12 food waste materials were evaluated by comparing the adsorbents’ efficiency for the removal of 23 elements from complex multi-element solutions, maintaining homogeneous experimental conditions. The examined materials resulted to be extremely efficient for the adsorption of many elements from synthetic multi-element solutions as well as from a heavy metal wastewater. The 12 adsorbent surfaces were analyzed by Fourier transform infrared spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements. By multivariate statistical computations of the obtained data, the 12 food waste materials were grouped in five clusters characterized by different elements’ removal efficiency which resulted to be in correlation with the specific adsorbents’ chemical structures. Banana peel, watermelon peel and grape waste resulted the least selective and the most efficient food waste materials for the removal of most of the elements. PMID:29495363

Efficiency Evaluation of Food Waste Materials for the Removal of Metals and Metalloids from Complex Multi-Element Solutions

Directory of Open Access Journals (Sweden)

Lorenzo Massimi

2018-02-01

Full Text Available Recent studies have shown the potential of food waste materials as low cost adsorbents for the removal of heavy metals and toxic elements from wastewater. However, the adsorption experiments have been performed in heterogeneous conditions, consequently it is difficult to compare the efficiency of the individual adsorbents. In this study, the adsorption capacities of 12 food waste materials were evaluated by comparing the adsorbents’ efficiency for the removal of 23 elements from complex multi-element solutions, maintaining homogeneous experimental conditions. The examined materials resulted to be extremely efficient for the adsorption of many elements from synthetic multi-element solutions as well as from a heavy metal wastewater. The 12 adsorbent surfaces were analyzed by Fourier transform infrared spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements. By multivariate statistical computations of the obtained data, the 12 food waste materials were grouped in five clusters characterized by different elements’ removal efficiency which resulted to be in correlation with the specific adsorbents’ chemical structures. Banana peel, watermelon peel and grape waste resulted the least selective and the most efficient food waste materials for the removal of most of the elements.

An Assessment of the SEA Multi-Element Sensor for Liquid Water Content Calibration of the NASA GRC Icing Research Tunnel

Science.gov (United States)

Steen, Laura E.; Ide, Robert F.; Van Zante, Judith F.

2015-01-01

The NASA Glenn Icing Research tunnel has been using an Icing Blade technique to measure cloud liquid water content (LWC) since 1980. The IRT conducted tests with SEA Multi-Element sensors from 2009 to 2011 to assess their performance in measuring LWC. These tests revealed that the Multi-Element sensors showed some significant advantages over the Icing Blade, particularly at higher water contents, higher impingement rates, and large drop sizes. Results of these and other tests are presented here.

Progress in multi-element silicon detectors for synchrotron XRF applications

International Nuclear Information System (INIS)

Ludewigt, B.; Rossington, C.; Kipnis, I.; Krieger, B.

1995-10-01

Multi-element silicon strip detectors, in conjunction with integrated circuit pulse-processing electronics, offer an attractive alternative to conventional lithium-drifted silicon and high purity germanium detectors for high count rate, low noise synchrotron x-ray fluorescence applications. We have been developing these types of detectors specifically for low noise synchrotron applications, such as extended x-ray absorption fine structure spectroscopy, microprobe x-ray fluorescence and total reflection x-ray fluorescence. The current version of the 192-element detector and integrated circuit preamplifier, cooled to -25 degrees C with a single-stage thermoelectric cooler, achieves an energy resolution of <200 eV full width of half maximum (FWHM) per channel (at 5.9 keV, 2 μs peaking time), and each detector element is designed to handle ∼20 kHz count rate. The detector system will soon be completed to 64 channels using new application specific integrated circuit (ASIC) amplifier chips, new CAMAC (Computer Automated Measurement and Control standard) analog-to-digital converters recently developed at Lawrence Berkeley National Laboratory (LBNL), CAMAC histogramming modules, and Macintosh-based data acquisition software. We report on the characteristics of this detector system, and the work in progress towards the next generation system

Minmax defense strategy for complex multi-state systems

International Nuclear Information System (INIS)

Hausken, Kjell; Levitin, Gregory

2009-01-01

This paper presents a general optimization methodology that merges game theory and multi-state system survivability theory. The defender has multiple alternatives of defense strategy that presumes separation and protection of system elements. The attacker also has multiple alternatives of its attack strategy based on a combination of different possible attack actions against different groups of system elements. The defender minimizes, and the attacker maximizes, the expected damage caused by the attack (taking into account the unreliability of system elements and the multi-state nature of complex series-parallel systems). The problem is defined as a two-period minmax non-cooperative game between the defender who moves first and the attacker who moves second. An exhaustive minmax optimization algorithm is presented based on a double-loop genetic algorithm for determining the solution. A universal generating function technique is applied for evaluating the losses caused by system performance reduction. Illustrative examples with solutions are presented

SU(3) techniques for angular momentum projected matrix elements in multi-cluster problems

International Nuclear Information System (INIS)

Hecht, K.T.; Zahn, W.

1978-01-01

In the theory of integral transforms for the evaluation of the resonating group kernels needed for cluster model calculations, the evaluation of matrix elements in an angular momentum coupled basis has proved to be difficult for cluster problems involving more than two fragments. For multi-cluster wave functions SU(3) coupling and recoupling techniques can furnish a tool for the practical evaluation matrix elements in an angular momentum coupled basis if the several relative motion harmonic oscillator functions in Bargmann space have simple SU(3) coupling properties. The method is illustrated by a three-cluster problem, such as 12 C = α + α + α, involving three 1 S clusters. 2 references

Multi-objective optimization of linear multi-state multiple sliding window system

International Nuclear Information System (INIS)

Konak, Abdullah; Kulturel-Konak, Sadan; Levitin, Gregory

2012-01-01

This paper considers the optimal element sequencing in a linear multi-state multiple sliding window system that consists of n linearly ordered multi-state elements. Each multi-state element can have different states: from complete failure up to perfect functioning. A performance rate is associated with each state. The failure of type i in the system occurs if for any i (1≤i≤I) the cumulative performance of any r i consecutive elements is lower than w i . The element sequence strongly affects the probability of any type of system failure. The sequence that minimizes the probability of certain type of failure can provide high probability of other types of failures. Therefore the optimization problem for the multiple sliding window system is essentially multi-objective. The paper formulates and solves the multi-objective optimization problem for the multiple sliding window systems. A multi-objective Genetic Algorithm is used as the optimization engine. Illustrative examples are presented.

Computational complexity and memory usage for multi-frontal direct solvers used in p finite element analysis

KAUST Repository

Calo, Victor M.; Collier, Nathan; Pardo, David; Paszyński, Maciej R.

2011-01-01

The multi-frontal direct solver is the state of the art for the direct solution of linear systems. This paper provides computational complexity and memory usage estimates for the application of the multi-frontal direct solver algorithm on linear systems resulting from p finite elements. Specifically we provide the estimates for systems resulting from C0 polynomial spaces spanned by B-splines. The structured grid and uniform polynomial order used in isogeometric meshes simplifies the analysis.

Computational complexity and memory usage for multi-frontal direct solvers used in p finite element analysis

KAUST Repository

Calo, Victor M.

2011-05-14

The multi-frontal direct solver is the state of the art for the direct solution of linear systems. This paper provides computational complexity and memory usage estimates for the application of the multi-frontal direct solver algorithm on linear systems resulting from p finite elements. Specifically we provide the estimates for systems resulting from C0 polynomial spaces spanned by B-splines. The structured grid and uniform polynomial order used in isogeometric meshes simplifies the analysis.

Evaluation of a two-step thermal method for separating organic and elemental carbon for radiocarbon analysis

NARCIS (Netherlands)

Dusek, U.; Monaco, M.; Prokopiou, M.; Gongriep, F.; Hitzenberger, R.; Meijer, H. A. J.; Rockmann, T.

2014-01-01

We thoroughly characterized a system for thermal separation of organic carbon (OC) and elemental carbon (EC) for subsequent radiocarbon analysis. Different organic compounds as well as ambient aerosol filter samples were introduced into an oven system and combusted to CO2 in pure O-2. The main

Rapid chemical separations

CERN Document Server

Trautmann, N

1976-01-01

A survey is given on the progress of fast chemical separation procedures during the last few years. Fast, discontinuous separation techniques are illustrated by a procedure for niobium. The use of such techniques for the chemical characterization of the heaviest known elements is described. Other rapid separation methods from aqueous solutions are summarized. The application of the high speed liquid chromatography to the separation of chemically similar elements is outlined. The use of the gas jet recoil transport method for nuclear reaction products and its combination with a continuous solvent extraction technique and with a thermochromatographic separation is presented. Different separation methods in the gas phase are briefly discussed and the attachment of a thermochromatographic technique to an on-line mass separator is shown. (45 refs).

Development of new extraction agents for separation of rare radioactive elements

International Nuclear Information System (INIS)

Hala, J.; Navratil, O.; Prihoda, J.; Smola, J.

1977-01-01

Certain transition elements, such as rhodium and palladium may be recovered from waste solutions produced in spent fuel reprocessing. The extraction of palladium was studied using sulfur compounds of the sulfide and sulfoxide types and the effects were investigated of the individual factors on palladium distribution between the aqueous and the organic phases. The possibility of separating hafnium in the form of extractable complexes was tested on several systems. Studied in more detail were mainly the complexes of hafnium with pyrocatechol violet, xylenol orange, and tributyl phosphate. The extraction of other metals, mainly of scandium, europium and indium was investigated in detail in the system acid aqueous phase - organophosphinic acids solution in benzene. (L.K.)

Multi Scale Finite Element Analyses By Using SEM-EBSD Crystallographic Modeling and Parallel Computing

International Nuclear Information System (INIS)

Nakamachi, Eiji

2005-01-01

A crystallographic homogenization procedure is introduced to the conventional static-explicit and dynamic-explicit finite element formulation to develop a multi scale - double scale - analysis code to predict the plastic strain induced texture evolution, yield loci and formability of sheet metal. The double-scale structure consists of a crystal aggregation - micro-structure - and a macroscopic elastic plastic continuum. At first, we measure crystal morphologies by using SEM-EBSD apparatus, and define a unit cell of micro structure, which satisfy the periodicity condition in the real scale of polycrystal. Next, this crystallographic homogenization FE code is applied to 3N pure-iron and 'Benchmark' aluminum A6022 polycrystal sheets. It reveals that the initial crystal orientation distribution - the texture - affects very much to a plastic strain induced texture and anisotropic hardening evolutions and sheet deformation. Since, the multi-scale finite element analysis requires a large computation time, a parallel computing technique by using PC cluster is developed for a quick calculation. In this parallelization scheme, a dynamic workload balancing technique is introduced for quick and efficient calculations

Clustering of samples and elements based on multi-variable chemical data

International Nuclear Information System (INIS)

Op de Beeck, J.

1984-01-01

Clustering and classification are defined in the context of multivariable chemical analysis data. Classical multi-variate techniques, commonly used to interpret such data, are shown to be based on probabilistic and geometrical principles which are not justified for analytical data, since in that case one assumes or expects a system of more or less systematically related objects (samples) as defined by measurements on more or less systematically interdependent variables (elements). For the specific analytical problem of data set concerning a large number of trace elements determined in a large number of samples, a deterministic cluster analysis can be used to develop the underlying classification structure. Three main steps can be distinguished: diagnostic evaluation and preprocessing of the raw input data; computation of a symmetric matrix with pairwise standardized dissimilarity values between all possible pairs of samples and/or elements; and ultrametric clustering strategy to produce the final classification as a dendrogram. The software packages designed to perform these tasks are discussed and final results are given. Conclusions are formulated concerning the dangers of using multivariate, clustering and classification software packages as a black-box

Effect of randomness on multi-frequency aeroelastic responses resolved by Unsteady Adaptive Stochastic Finite Elements

International Nuclear Information System (INIS)

Witteveen, Jeroen A.S.; Bijl, Hester

2009-01-01

The Unsteady Adaptive Stochastic Finite Elements (UASFE) method resolves the effect of randomness in numerical simulations of single-mode aeroelastic responses with a constant accuracy in time for a constant number of samples. In this paper, the UASFE framework is extended to multi-frequency responses and continuous structures by employing a wavelet decomposition pre-processing step to decompose the sampled multi-frequency signals into single-frequency components. The effect of the randomness on the multi-frequency response is then obtained by summing the results of the UASFE interpolation at constant phase for the different frequency components. Results for multi-frequency responses and continuous structures show a three orders of magnitude reduction of computational costs compared to crude Monte Carlo simulations in a harmonically forced oscillator, a flutter panel problem, and the three-dimensional transonic AGARD 445.6 wing aeroelastic benchmark subject to random fields and random parameters with various probability distributions.

Theoretical background and implementation of the finite element method for multi-dimensional Fokker-Planck equation analysis

Czech Academy of Sciences Publication Activity Database

Král, Radomil; Náprstek, Jiří

2017-01-01

Roč. 113, November (2017), s. 54-75 ISSN 0965-9978 R&D Projects: GA ČR(CZ) GP14-34467P; GA ČR(CZ) GA15-01035S Institutional support: RVO:68378297 Keywords : Fokker-Planck equation * finite element method * simplex element * multi-dimensional problem * non-symmetric operator Subject RIV: JM - Building Engineering OBOR OECD: Mechanical engineering Impact factor: 3.000, year: 2016 https://www.sciencedirect.com/science/ article /pii/S0965997817301904

Radioactivity in the pelagic fish. II. Group separation of radioactive elements in fish tissues

Energy Technology Data Exchange (ETDEWEB)

Yamada, K; Tozawa, H; Amano, K; Takase, A

1955-01-01

Analytical group separation was performed with various ashed tissues of some fishes exposed to radioactive ash. The radioactivity was particularly large with elements belonging to the 3rd group, both A and B subgroups. The 2nd group showed considerable activity in pyloric ceca and kidney of Skipjacks. The radioactivity of the 1st and 4th groups was detected in some tissues; the 5th group showed slight activity.

Design considerations regarding an atomizer for multi-element electrothermal atomic absorption spectrometry

Energy Technology Data Exchange (ETDEWEB)

Katskov, Dmitri A., E-mail: katskovda@tut.ac.za [Department of Chemistry, Tshwane University of Technology, Private Bag X680, Pretoria 0001 (South Africa); Sadagov, Yuri M. [All-Russian Scientific Research Institute of Optical and Physical Measurements (VNIIOFI), Ozernaya St. 46, Moscow 119361 (Russian Federation)

2011-06-15

The methodology of simultaneous multi-element electrothermal atomic absorption spectrometry (ETAAS-Electrothermal Atomic Absorption Spectrometry) stipulates rigid requirements to the design and operation of the atomizer. It must provide high degree of atomization for the group of analytes, invariant respective to the vaporization kinetics and heating ramp residence time of atoms in the absorption volume and absence of memory effects from major sample components. For the low resolution spectrometer with a continuum radiation source the reduced compared to traditional ETAAS (Electrothermal Atomic Absorption Spectrometry) sensitivity should be, at least partially, compensated by creating high density of atomic vapor in the absorption pulse. The sought-for characteristics were obtained for the 18 mm in length and 2.5 mm in internal diameter longitudinally heated graphite tube atomizer furnished with 2-4.5 mg of ring shaped carbon fiber yarn collector. The collector located next to the sampling port provides large substrate area that helps to keep the sample and its residue in the central part of the tube after drying. The collector also provides a 'platform' effect that delays the vaporization and stipulates vapor release into absorption volume having already stabilized gas temperature. Due to the shape of external surface of the tube, presence of collector and rapid (about 10 {sup o}C/ms) heating, an inverse temperature distribution along the tube is attained at the beginnings of the atomization and cleaning steps. The effect is employed for cleaning of the atomizer using the set of short maximum power heating pulses. Preparation, optimal maintenance of the atomizer and its compliance to the multi-element determination requirements are evaluated and discussed. The experimental setup provides direct simultaneous determination of large group of element within 3-4 order concentration range. Limits of detection are close to those for sequential single element

Neutron activation analysis of trace elements in foodstuffs

International Nuclear Information System (INIS)

Schelenz, R.; Fischer, E.

1976-05-01

A neutron activation method for multielement determination in biological material was developed. The individual steps of the method include radiochemical processing as well as nondestructive techniques. In order to develop a high resolution gamma spectrometric method the indispensable assumptions were the application of Ge(Li)-semiconductor detectors, multi-channel pulse height analyzers and the use of electronic data evaluation with mini-computers for the automatic evaluation of complex gamma spectra. After radiochemical separation (RNAA) 33 elements can be determined in biological materials and by application of nondestructive, purely instrumental techniques (INAA) 25 elements. The time required for the analysis of 33 elements can be determined in biological materials and by application of nondestructive, purely instrumental techniques (INAA) 25 elements. The time required for the analysis of 33 elements is 4 days. The neutron activation method is used routinely for the determination of trace elements in foodstuffs and in the field of nutrition research. (orig.) [de

chemical studies on the reactivity of some organic extractants for extraction and separation of certain elements from aqueous solutions

International Nuclear Information System (INIS)

Aly, M.M.I.

2010-01-01

Lanthanide elements such as lanthanum and neodymium are important elements in photo-electronic and metallurgical industries as well as in nuclear technology. The main constituents of the spent nuclear fuel are actinides like uranium, thorium and various fission products including lanthanides. The co-ordination compounds of the trivalent lanthanum and neodymium continues to be an active research area, which includes the specific spectroscopic and magnetic properties of rare earth ions and their applications as super molecular device, contrast-enhancing agents in magnetic resonance imaging, optical signal amplifiers and electroluminescent (EL) devices. Hence, the separation and purification of these elements is of great concern. Solvent extraction technique is employed to separate and purify rare earth elements in an industrial scale, but the separation of lanthanum and neodymium is a difficult task, as lanthanide ions exhibit similar chemical and physical properties. They have generally common and stable +3 oxidation state that requires synthesis of certain extractants which are able to extract them from different aqueous solutions. During the last twenty years, different publications have pointed out the remarkable properties of alkyl amide in the field of separation chemistry. These extractants are able to form stable co-ordination compounds with different metallic ions. In this concern, this thesis deals with the synthesis of different amide extractants namely N, N diethylacetoamide (DEAA), N, N Teteraphenyl malonamide (TPMA), N, N diphenylbenzamide (DPBA), N, N' diphenylacetoamide (DPAA), and N, N' Teteraethyl malonamide (TEMA), which were synthesized, characterized and compared with Aliquat-336 in kerosene for extraction and separation of La (III) and Nd (III). The effect of the different parameters affecting the extraction of these metals from aqueous nitric acid medium in the different systems has been studied in terms of shaking time, nitric acid, hydrogen

Separation by sequential chromatography of americium, plutonium and neptunium elements: application to the study of trans-uranian elements migration in a European lacustrine system

International Nuclear Information System (INIS)

Michel, H.

1999-01-01

The nuclear tests carried out in the atmosphere in the Sixties, the accidents and in particular that to the power station of Chernobyl in 1986, were at the origin of the dispersion of a significant quantity of transuranic elements and fission products. The study of a lake system, such that of the Blelham Tarn in Great Britain, presented in this memory, can bring interesting answers to the problems of management of the environment. The determination of the radionuclides in sediment cores made it possible not only to establish the history of the depositions and consequently the origin of the radionuclides, but also to evaluate the various transfers which took place according to the parameters of the site and the properties of the elements. The studied transuranic elements are plutonium 238, 239-240, americium 241 and neptunium 237. Alpha emitting radionuclides, their determination requires complex radiochemical separations. A method was worked out to successively separate the three radioelements by using a same chromatographic column. Cesium 137 is the studied fission product, its determination is done by direct Gamma spectrometry. Lead 210, natural radionuclide, whose atmospheric flow can be supposed constant. makes it possible to obtain a chronology of the various events. The detailed vertical study of sediment cores showed that the accumulation mode of the studied elements is the same one and that the methods of dating converge. The cesium, more mobile than transuranic elements in the atmosphere, was detected in the 1963 and 1986 fallout whereas an activity out of transuranic elements appears only for the 1963 fallout. The activity of the 1963 cesium fallout is of the same order of magnitude as that of 1986. The calculation of the diffusion coefficients of the elements in the sediments shows an increased migration of cesium compared to transuranic elements. An inventory on the whole of the lake made it possible to note that the atmospheric fallout constitute the

Determination of rare earth elements in rocks by neutron activation analysis with pre-irradiation separation

International Nuclear Information System (INIS)

Alcala, A.L.

1991-01-01

Rare earth elements were determined by neutron activation analysis in rocks, a group separation before irradiation was developed. The international reference standards AGV-1, BE-N and JB-1, as well the Brazilian geological standards BB-1 and GB-1, provided by the Instituto de Geociencias da Universidade Federal da Bahia, were analysed. The method was based on acid digestion of the samples, cation exchange separation, and coprecipitation of the REE with calcium oxalate. Interferents like U, Th, Ta and Fe were eliminated. The concentration values of eleven REE's (La, Co, Pr, Nd, Sm, Eu, Gd, Tb, Ho, Yb and Lu) were determined. (author)

Evaluation of a multi-site program designed to strengthen relational bonds for siblings separated by foster care.

Science.gov (United States)

Waid, Jeffrey; Wojciak, Armeda Stevenson

2017-10-01

Sibling relationships in foster care settings have received increased attention in recent years. Despite growing evidence regarding the protective potential of sibling relationships for youth in care, some sibling groups continue to experience foster care related separation, and few programs exist to address the needs of these youth. This study describes and evaluates Camp To Belong, a multi-site program designed to provide short-term reunification to separated sibling groups through a week-long summer camp experience. Using a pre-test post-test survey design, this paper examines changes in youth ratings of sibling conflict and sibling support across camps located in six geographically distinct regions of the United States. The effects of youth age, number of prior camp exposures, and camp location were tested using multilevel modeling procedures. Findings suggest that participation in Camp To Belong may reduce sibling conflict, and improvements in sibling support are noted for youth who have had prior exposure to the camp's programming. Camp-level variance in the sibling support outcome highlight the complex nature of relationships for siblings separated by foster care, and suggest the need for additional research. Lessons learned from this multi-site evaluation and future directions are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Finite Element Modeling of Adsorption Processes for Gas Separation and Purification

International Nuclear Information System (INIS)

Humble, Paul H.; Williams, Richard M.; Hayes, James C.

2009-01-01

Pacific Northwest National Laboratory (PNNL) has expertise in the design and fabrication of automated radioxenon collection systems for nuclear explosion monitoring. In developing new systems there is an ever present need to reduce size, power consumption and complexity. Most of these systems have used adsorption based techniques for gas collection and/or concentration and purification. These processes include pressure swing adsorption, vacuum swing adsorption, temperature swing adsorption, gas chromatography and hybrid processes that combine elements of these techniques. To better understand these processes, and help with the development of improved hardware, a finite element software package (COMSOL Multiphysics) has been used to develop complex models of these adsorption based operations. The partial differential equations used include a mass balance for each gas species and adsorbed species along with a convection conduction energy balance equation. These equations in conjunction with multicomponent temperature dependent isotherm models are capable of simulating separation processes ranging from complex multibed PSA processes, and multicomponent temperature programmed gas chromatography, to simple two component temperature swing adsorption. These numerical simulations have been a valuable tool for assessing the capability of proposed processes and optimizing hardware and process parameters.

Spatial separation and bidirectional trafficking of proteins using a multi-functional reporter

Directory of Open Access Journals (Sweden)

Klaubert Dieter H

2008-04-01

Full Text Available Abstract Background The ability to specifically label proteins within living cells can provide information about their dynamics and function. To study a membrane protein, we fused a multi-functional reporter protein, HaloTag®, to the extracellular domain of a truncated integrin. Results Using the HaloTag technology, we could study the localization, trafficking and processing of an integrin-HaloTag fusion, which we showed had cellular dynamics consistent with native integrins. By labeling live cells with different fluorescent impermeable and permeable ligands, we showed spatial separation of plasma membrane and internal pools of the integrin-HaloTag fusion, and followed these protein pools over time to study bi-directional trafficking. In addition to combining the HaloTag reporter protein with different fluorophores, we also employed an affinity tag to achieve cell capture. Conclusion The HaloTag technology was used successfully to study expression, trafficking, spatial separation and real-time translocation of an integrin-HaloTag fusion, thereby demonstrating that this technology can be a powerful tool to investigate membrane protein biology in live cells.

Analysis and separation of lanthanide elements

International Nuclear Information System (INIS)

Almeida Pimentel, E. de.

1973-01-01

Improvements of rare earth separation by the combined use of acetic and critic acid were studied and analytical methods for determining some of the lanthanides were tryed out. Separations of the R.E. studied were favorable when citric acid (solution A) and acetic acid (solution B) were used in the proportion of 10:1 at pH=4,00. Neutron activation, spectro-photometric, polarographic, volumetric and gravimetric procedures allowed the determination of 8 R.E.; samarium, neodymium, praseodymium, lanthanum, cerium, holmium, erbium and europium

Isotope separation process

International Nuclear Information System (INIS)

Cox, D.M.; Maas, E.T.

1982-01-01

Processes are disclosed for the separation of isotopes of an element comprising vaporizing uranyl compounds having the formula (UO2a2)n, where a is a monovalent anion and n in an integer from 2 to 4, the compounds having an isotopically shifted infrared absorption spectrum associated with uranyl ions containing said element which is to be separated, and then irradiating the uranyl compound with infrared radiation which is preferentially absorbed by a molecular vibration of uranyl ions of the compound containing a predetermined isotope of that element so that excited molecules of the compound are provided which are enriched in the molecules of the compound containing that predetermined isotope, thus enabling separation of these excited molecules. The processes disclosed include separation of the excited molecules by irradiating under conditions such that the excited molecules dissociate, and also separating the excited molecules by a discrete separation step. The latter includes irradiating the excited molecules by a second infrared laser in order to convert the excited molecules into a separable product, or also by chemically converting the excited molecules, preferably by reaction with a gaseous reactant

A new XRF probe for in-situ determining concentration of multi-elements in ocean sediments

International Nuclear Information System (INIS)

Ge Liangquan; Lai Wanchang; Zhou Sichun; Lin Ling; Lin Yanchang; Ren Jiafu

2001-01-01

The author introduces a new X-ray fluorescence probe for in-situ determining the concentration of multi-elements in ocean sediments. The probe consists of Si-Pin X-ray detector with an electro-thermal colder, two isotope sources, essential electrical signal processing units and a notebook computer. More than 10 elements can be simultaneously determined at a detection limit of (10-200) x 10 -6 and precision of 5%-30% without liquid Nitrogen supply. tests show that the probe can perform the analytical tasks under the water at the depth of less than 1000 meters

Costs of head-end incineration with respect to Kr separation in the reprocessing of HTR fuel elements

Energy Technology Data Exchange (ETDEWEB)

Barnert-Wiemer, H.; Boehnert, R.

1976-07-15

The C-incinerations and the Kr-separations during head-end incineration in the reprocessing of HTR fuel elements are described. The costs for constructing an operating a head-end incineration of reprocessing capacities with 5,000 to 50,000 MW(e)-HTR power have been determined. The cost estimates are divided into investment and operating costs, further after the fraction of the N/sub 2/-content in the incineration exhaust gas, which strongly affects costs. It appears that, in the case of Kr-separation from the incineration exhaust gas, the investment costs as well as the operating costs of the head-end for N/sub 2/-containing exhaust gas are considerably greater than those for gas without N/sub 2/. The C-incineration of the graphite of the HTR fuel elements should therefore only be performed with influx gas that is free of N/sub 2/.

Usage of air jigging for multi-component separation of construction and demolition waste.

Science.gov (United States)

Ambrós, Weslei Monteiro; Sampaio, Carlos Hoffmann; Cazacliu, Bogdan Grigore; Miltzarek, Gerson Luis; Miranda, Leonardo R

2017-02-01

The use of air jigging for performing multi-component separation in the treatment of mixed construction and demolition waste was studied. Sorting tests were carried out with mixtures of equal bulk volume of concrete and brick in which fixed quantities of unwanted materials - gypsum, wood and paper - were added. Experimental results have demonstrated the possibility to use air jigging to carry out both the removal of low-density contaminants and the concrete concentration in only one process step. In relation to the removal of contaminants only, the overall performance of jigging process can be comparable with that of commercial air classifiers and automatic sorting systems. Also, the initial content of contaminants seems does not have a significant effect on the separation extent. These results are of particular importance for recycling plants processing as they represent an alternative to optimize the use of air jigs. Further investigation is needed in order to evaluate the practical feasibility of such method. Copyright © 2016 Elsevier Ltd. All rights reserved.

Generation of a multi-photon Greenberger-Horne-Zeilinger state with linear optical elements and photon detectors

International Nuclear Information System (INIS)

Zou, X B; Pahlke, K; Mathis, W

2005-01-01

We present a scheme to generate a multi-photon Greenberger-Horne-Zeilinger (GHZ) state by using single-photon sources, linear optical elements and photon detectors. Such a maximum entanglement has wide applications in the demonstration of quantum nonlocality and quantum information processing

Overview of multi-element monolithic germanium detectors for XAFS experiments at diamond light source

International Nuclear Information System (INIS)

Chatterji, S.; Dennis, G. J.; Dent, A.; Diaz-Moreno, S.; Cibin, G.; Tartoni, N.; Helsby, W. I.

2016-01-01

An overview of multi-element monolithic germanium detectors being used at the X-ray absorption spectroscopy (XAS) beam lines at Diamond Light Source (DLS) is being reported. The hardware details and a summary of the performance of these detectors have also been provided. Recent updates about various ongoing projects being worked on to improve the performance of these detectors are summarized.

Overview of multi-element monolithic germanium detectors for XAFS experiments at diamond light source

Energy Technology Data Exchange (ETDEWEB)

Chatterji, S.; Dennis, G. J.; Dent, A.; Diaz-Moreno, S.; Cibin, G.; Tartoni, N. [Diamond Light Source Ltd, Oxfordshire (United Kingdom); Helsby, W. I. [STFC Daresbury Laboratory, Warrington (United Kingdom)

2016-07-27

An overview of multi-element monolithic germanium detectors being used at the X-ray absorption spectroscopy (XAS) beam lines at Diamond Light Source (DLS) is being reported. The hardware details and a summary of the performance of these detectors have also been provided. Recent updates about various ongoing projects being worked on to improve the performance of these detectors are summarized.

Multi-Element Analysis and Geochemical Spatial Trends of Groundwater in Rural Northern New York

Directory of Open Access Journals (Sweden)

Michael O’Connor

2010-05-01

Full Text Available Samples from private wells (n = 169 throughout St. Lawrence County, NY were analyzed by ICP-MS multi-element techniques. St. Lawrence County spans three diverse bedrock terranes including Precambrian crystalline rocks of the Adirondack Lowlands (mostly paragneisses and Highlands (mostly orthogneisses, as well as Paleozoic sedimentary rocks of the St. Lawrence Valley. An ArcGIS database was constructed and used to generate contour plots for elements across the county. Strontium isotopes and unique geochemical signatures were used to distinguish water from various geologic units. The results were consistent with a large (7,309 km2, sparsely populated (~110,000, rural region with diverse bedrock and glacial cover.

Process to separate transuranic elements from nuclear waste

Science.gov (United States)

Johnson, T.R.; Ackerman, J.P.; Tomczuk, Z.; Fischer, D.F.

1989-03-21

A process is described for removing transuranic elements from a waste chloride electrolytic salt containing transuranic elements in addition to rare earth and other fission product elements so the salt waste may be disposed of more easily and the valuable transuranic elements may be recovered for reuse. The salt is contacted with a cadmium-uranium alloy which selectively extracts the transuranic elements from the salt. The waste salt is generated during the reprocessing of nuclear fuel associated with the Integral Fast Reactor (IFR). 2 figs.

Process to separate transuranic elements from nuclear waste

International Nuclear Information System (INIS)

Johnson, T.R.; Ackerman, J.P.; Tomczuk, Z.; Fischer, D.F.

1989-01-01

A process is described for removing transuranic elements from a waste chloride electrolytic salt containing transuranic elements in addition to rare earth and other fission product elements so the salt waste may be disposed of more easily and the valuable transuranic elements may be recovered for reuse. The salt is contacted with a cadmium-uranium alloy which selectively extracts the transuranic elements from the salt. The waste salt is generated during the reprocessing of nuclear fuel associated with the Integral Fast Reactor (IFR). 2 figs

Beam Dynamics Simulations of the REX-ISOLDE A/q-separator

CERN Document Server

Fraser, M A; Wenander, F

2014-01-01

The REX-ISOLDE A=q-separator selects the radioactive species of interest from the background of residual gas ions coming from the EBIS ion source. In the context of the HIE-ISOLDE upgrade, including the implementation of a multi-harmonic buncher and an upgraded EBIS, the separator and the beam line between the EBIS and RFQ, which we will call the Low Energy Beam Transfer (LEBT) line, has been simulated by tracking particles through the field maps of each active element using the TRACK [4] code. The simulations were benchmarked with a COSY-1 model that was improved to take into account the fringe fields of the electrostatic quadrupoles, electrostatic deflector and magnetic bender; the model can be used to tune and optimise the separator with higher-order effects taken into account. In this note the beam dynamics simulations are documented and the transverse and longitudinal acceptance of the separator line studied to provide design constraints for the EBIS upgrade.

Multi-component transport in polymers: hydrocarbon / hydrogen separation by reverse selectivity membrane; Transport multi-composants dans les polymeres: separation hydrocarbures / hydrogene par membrane a selectivite inverse

Energy Technology Data Exchange (ETDEWEB)

Mauviel, G.

2003-12-15

Hydrogen separation by reverse selectivity membranes is investigated. The first goal is to develop materials showing an increased selectivity. Silicone membranes loaded with inorganic fillers have been prepared, but the expected enhancement is not observed. The second goal is to model the multi- component transport through rubbers. Indeed the permeability model is not able to predict correctly permeation when a vapour is present. Thus many phenomena have to be considered: diffusional inter-dependency, sorption synergy, membrane swelling and drag effect. The dependence of diffusivities with the local composition is modelled according to free-volume theory. The model resolution allows to predict the permeation flow-rates of mixed species from their pure sorption and diffusion data. For the systems under consideration, the diffusional inter-dependency is shown to be preponderant. Besides, sorption synergy importance is pointed out, whereas it is most often neglected. (author)

Fixation and separation of the elements thorium and uranium using anion exchange resins in nitrate solution

International Nuclear Information System (INIS)

Korgaonkar, V.

1967-10-01

The exchange of thorium and uranium between a strong base anion resin and a mixed water + ethanol solvent containing nitrate ions is studied. It is assumed that in the resin the thorium and uranium are fixed in the form of the complexes Th(NO 3 ) 6 2- and UO 2 (NO 3 ) 4 2- in solution these elements are present in the form of complexes having the general formula: Th(NO 3 ) 6-n n-2 and UO 2 (NO 3 ) 4-n n-2 It has been possible to deduce a law for the changes in the partition functions of thorium and uranium as a function of the concentrations of the various species in solution and of the complexing ion NO 3 . From this has been deduced the optimum operational conditions for separating a mixture of these two elements. Finally, in these conditions, the influence of a few interfering ions has been studied: Ba, Bi, Ce, La, Mo, Pb, Zr. The method proposed can be used either as a preparation, or for the dosage of thorium by a quantitative separation. (author) [fr

Multi-element neutron activation analysis of Brazilian coal samples

International Nuclear Information System (INIS)

Atalla, L.T.; Requejo, C.S.

1982-09-01

The elements U, Th, La, Ce, Nd, Sm, Eu, Dy, Tb, Yb, Lu, Sc, Ta, Hf, Co, Ni, Cr, Mo, Ti, V, W, In, Ga, Mn, Ba, Sr, Mg, Rb, Cs, K, Cl, Br, As, Sb, Au, Ca, Al and Fe were determined in coal samples by instrumental neutron activation analysis, by using both thermal and epithermal neutron irradiations. The irradiation times were 10 minutes and 8 or 16 hours in a position where the thermal neutron flux was about 10 12 n.cm - 2 .s - 1 and 72 non-consecutive hours for epithermal irradiation at a flux of about 10 11 n.Cm - 2 .s - 1 . After the instrumental analysis of the above mentioned elements, Zn and Se were determined with chemical separation. The relative standard deviation of, at least, 4 determinations was about + - 10% for the majority of the results. The coal samples analysed were supplied by: Cia. Estadual da Tecnologia e Saneamento Basico (CETESB-SP), Cia. de Pesquisas e Lavras Minerais (COPELMI-RS), Cia. Carbonifera Urussunga (SC), Cia. Carbonifera Prospera (SC), Cia. Carbonifera Treviso (SC), Cia. Nacional de Mineracao de Carvao do Barro Branco (SC) and Comissao Nacional de Energia Nuclear (CNEN-RJ). (Author) [pt

The Multi-Element Electronstatic Lens Systems for Controlling and Focusing Charged Particle

International Nuclear Information System (INIS)

Sise, O.

2004-01-01

Particle optics are very close anolog of photon optics and most of the principles of an barged particle beam can be understood by thinking of the particles as rays of light. There are similar behaviours between particle and photon optics in controlling beams of light and charged particles, such as lenses and mirrors. Extensive information about the properties of charged particle optics, from which appropriate systems can be designed for any specific problem. In this way electrostatic lens systems are used to control beams of c/iarged particle with various energy and directions in several fields, for example electron microscopy, cathode ray tubes, ion accelerators and electron impact studies. In an electrostatic lens system quantative information is required over a wide energy range and a zoom-type of optics is needed. If the magnification is to remain constant over a wide range of energies, quite complicated electrostatic lens systems are required, .containing three, four, five, or even more lens elements. We firstly calculated the optical properties of three and four element cylinder electrostatic lenses with the help of the SIMION and LENSYS programs and developed the method for the calculation of the focal properties of five and more element lenses with afocal mode. In this method we used the combination of three and four element lenses to derive focal properties of multi-element lenses and presented this data over a wide range of energy

[Rapid multi-elemental analysis on four precious Tibetan medicines based on LIBS technique].

Science.gov (United States)

Liu, Xiao-na; Shi, Xin-yuan; Jia, Shuai-yun; Zhao, Na; Wu, Zhi-sheng; Qiao, Yan-jiang

2015-06-01

The laser-induced breakdown spectroscopy (LIBS) was applied to perform a qualitative elementary analysis on four precious Tibetan medicines, i. e. Renqing Mangjue, Renqing Changjue, 25-herb coral pills and 25-herb pearl pills. The specific spectra of the four Tibetan medicines were established. In the experiment, Nd: YAG and 1 064 nm-baseband pulse laser were adopted to collect the spectra. A laser beam focused on the surface of the samples to generate plasma. Its spectral signal was detected by using spectrograph. Based on the National Institute of Standard and Technology (NIST) database, LIBS spectral lines were indentified. The four Tibetan medicines mainly included Ca, Na, K, Mg and other elements and C-N molecular band. Specifically, Fe was detected in Renqing Changjue and 25-herb pearl pills; heavy mental elements Hg and Cu were shown in Renqing Mangjue and Renqing Changjue; Ag was found in Renqing Changjue. The results demonstrated that LIBS is a reliable and rapid multi-element analysis on the four Tibetan medicines. With Real-time, rapid and nondestructive advantages, LIBS has a wide application prospect in the element analysis on ethnic medicines.

Investigation of equilibrium core by recycling MA and LLFP in fast reactor cycle. 2. Investigation of LLFP confined in Equilibrium Core with element separation

International Nuclear Information System (INIS)

Mizutani, Akihiko; Shono, Akira; Ishikawa, Makoto

2000-02-01

A feasibility study has been performed on a self-consistent fuel cycle system in the nuclear fuel recycle system with fast reactors. In this system, the self-generated MAs (Minor Actinides) and LLFPs (Long-Lived Fission Products) are confined and incinerated in the fast reactor, which is called the 'Equilibrium Core' concept. However, as the isotope separations for selected LLFPs have been assumed in this cycle system, it seems that this assumption is far from realistic one from the viewpoint of economy with respect to the fuel cycle system. In this study, the possibility for realization of the 'Equilibrium Core' concept is evaluated for three fuel types such as oxide, nitride and metallic fuels, provided that the isotopic separation of LLFPs is changed to the element one. This study provides, that is to say, how many LLFP elements can be confined in the 'Equilibrium Core' with element separation. This report examines the nuclear properties of the Equilibrium Core' for various combinations of LLFP incineration schemes from the viewpoints of the risk of geological disposal and the limit in confinable quantity of LLFPs. From the viewpoint of the risk of geological disposal estimated by the retardation factor, it is possible to confine with element separation for Tc, I and Se even in the oxide fueled core. From the standpoint of the limit of confinable amounts of LLFPs, on the other hand, Tc, I, Se, Sn and Cs can be confined with element separate only in case that the nitride fuel is chosen. (author)

Multi-objective Calibration of DHSVM Based on Hydrologic Key Elements in Jinhua River Basin, East China

Science.gov (United States)

Pan, S.; Liu, L.; Xu, Y. P.

2017-12-01

Abstract: In physically based distributed hydrological model, large number of parameters, representing spatial heterogeneity of watershed and various processes in hydrologic cycle, are involved. For lack of calibration module in Distributed Hydrology Soil Vegetation Model, this study developed a multi-objective calibration module using Epsilon-Dominance Non-Dominated Sorted Genetic Algorithm II (ɛ-NSGAII) and based on parallel computing of Linux cluster for DHSVM (ɛP-DHSVM). In this study, two hydrologic key elements (i.e., runoff and evapotranspiration) are used as objectives in multi-objective calibration of model. MODIS evapotranspiration obtained by SEBAL is adopted to fill the gap of lack of observation for evapotranspiration. The results show that good performance of runoff simulation in single objective calibration cannot ensure good simulation performance of other hydrologic key elements. Self-developed ɛP-DHSVM model can make multi-objective calibration more efficiently and effectively. The running speed can be increased by more than 20-30 times via applying ɛP-DHSVM. In addition, runoff and evapotranspiration can be simulated very well simultaneously by ɛP-DHSVM, with superior values for two efficiency coefficients (0.74 for NS of runoff and 0.79 for NS of evapotranspiration, -10.5% and -8.6% for PBIAS of runoff and evapotranspiration respectively).

Fast sequential multi-element determination of major and minor elements in environmental samples and drinking waters by high-resolution continuum source flame atomic absorption spectrometry.

Science.gov (United States)

Gómez-Nieto, Beatriz; Gismera, Ma Jesús; Sevilla, Ma Teresa; Procopio, Jesús R

2015-01-07

The fast sequential multi-element determination of 11 elements present at different concentration levels in environmental samples and drinking waters has been investigated using high-resolution continuum source flame atomic absorption spectrometry. The main lines for Cu (324.754 nm), Zn (213.857 nm), Cd (228.802 nm), Ni (232.003 nm) and Pb (217.001 nm), main and secondary absorption lines for Mn (279.482 and 279.827 nm), Fe (248.327, 248.514 and 302.064 nm) and Ca (422.673 and 239.856 nm), secondary lines with different sensitivities for Na (589.592 and 330.237 nm) and K (769.897 and 404.414 nm) and a secondary line for Mg (202.582 nm) have been chosen to perform the analysis. A flow injection system has been used for sample introduction so sample consumption has been reduced up to less than 1 mL per element, measured in triplicate. Furthermore, the use of multiplets for Fe and the side pixel registration approach for Mg have been studied in order to reduce sensitivity and extend the linear working range. The figures of merit have been calculated and the proposed method was applied to determine these elements in a pine needles reference material (SRM 1575a), drinking and natural waters and soil extracts. Recoveries of analytes added at different concentration levels to water samples and extracts of soils were within 88-115% interval. In this way, the fast sequential multi-element determination of major and minor elements can be carried out, in triplicate, with successful results without requiring additional dilutions of samples or several different strategies for sample preparation using about 8-9 mL of sample. Copyright © 2014 Elsevier B.V. All rights reserved.

A new XRF probe for in-situ determining concentration of multi-elements in ocean sediments

CERN Document Server

Ge Liang Quan; Zhou Si Chun; Lin Ling; Lin Yan Chang; Ren Jia Fu

2001-01-01

The author introduces a new X-ray fluorescence probe for in-situ determining the concentration of multi-elements in ocean sediments. The probe consists of Si-Pin X-ray detector with an electro-thermal colder, two isotope sources, essential electrical signal processing units and a notebook computer. More than 10 elements can be simultaneously determined at a detection limit of (10-200) x 10 sup - sup 6 and precision of 5%-30% without liquid Nitrogen supply. tests show that the probe can perform the analytical tasks under the water at the depth of less than 1000 meters

Analysis and Implementation of an Open Programmable Router Based on Forwarding and Control Element Separation

Institute of Scientific and Technical Information of China (English)

Wei-Ming Wang; Li-Gang Dong; Bin Zhuge

2008-01-01

A router architecture based upon ForCES (Forwarding and Control Element Separation), which is being standardized by IETF ForCES working group, gains its competitive advantage over traditional router architectures in flexibility, programmability, and cost-effectiveness. In this paper, design and implementation of a ForCES-based router (ForTER) is illustrated. Firstly, the implementation architecture of ForTER is discussed. Then, a layered software model,which well illustrates ForCES features, is proposed. Based on the model, design and implementation of Control Element (CE) and Forwarding Element (FE) in ForTER are introduced in detail. Moreover, security for ForTER is considered and an algorithm to prevent DoS attacks is presented. Lastly, experiments of ForTER are illustrated for routing and running routing protocols, network management, DoS attack prevention, etc. The experimental results show the feasibility of the ForTER design. Consequently, the ForTER implementation basically testifies the feasibility of ForCES architecture and some IETF ForCES specifications.

Multi-element analysis of lubricant oil by WDXRF technique using thin-film sample preparation

International Nuclear Information System (INIS)

Scapin, M. A.; Salvador, V. L. R.; Lopes, C. D.; Sato, I. M.

2006-01-01

The quantitative analysis of the chemical elements in matrices like oils or gels represents a challenge for the analytical chemists. The classics methods or instrumental techniques such as atomic absorption spectrometry (AAS) and plasma optical emission spectrometry (ICP-OES) need chemical treatments, mainly sample dissolution and degradation processes. X-ray fluorescence technique allows a direct and multi-element analysis without previous sample treatments. In this work, a sensible method for the determination of elements Mg, Al, Si, P, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Ag, Sn, Ba and Pb in lubricating oil is presented. The x-ray fluorescence (WDXRF) technique using linear regression method and thin film sample preparation was used. The validation of the methodology (repeatability and accuracy) was obtained by the analysis of the standard reference materials SRM Alpha AESAR lot 703527D, applying the Chauvenet, Cochrane, ANOVA and Z-score statistical tests. The method presents a relative standard deviation lower than 10% for all the elements, except for Pb determination (RSD Pb 15%). The Z-score values for all the elements were in the range -2 < Z < 2, indicating a very good accuracy.(Full text)

Determination of rare earth elements by liquid chromatographic separation using inductively coupled plasma mass spectrometric detection

International Nuclear Information System (INIS)

Braverman, D.S.

1992-01-01

High-performance liquid chromatography (HPLC) is used to separate the rare earth elements (REEs) prior to detection by inductively coupled plasma mass spectrometry (ICP-MS). The use of HPLC-ICP-MS in series combines the separation power and speed of HPLC with the sensitivity, isotopic selectivity and speed of ICP-MS. The detection limits for the REEs are in the sub-ng ml -1 range and the response is linear over four orders of magnitude. A preliminary comparison of isotope dilution and external standard results for the determination of REEs in National Institute of Standards and Technology (NIST) Standard Reference Material (SRM 1633a) Fly Ash is presented. (author)

Low-resolution continuum source simultaneous multi-element electrothermal atomic absorption spectrometry: steps into practice

International Nuclear Information System (INIS)

Katskov, Dmitri

2015-01-01

The theory and practical problems of continuum source simultaneous multi-element electrothermal atomic absorption spectrometry (SMET AAS) are discussed by the example of direct analysis of underground water. The experimental methodology is based on pulse vaporization of the sample in a fast heated graphite tube and measurement of transient absorption of continuum spectrum radiation from D 2 and Xe lamps within 200–400 nm wavelengths range with a low resolution spectral instrument and linear charge-coupled device. The setup permits the acquisition of 200 spectra during 1 s atomization pulse. Respective data matrix absorbance vs wavelength/time is employed for the quantification of elements in the sample. The calculation algorithm developed includes broad band and continuum background correction, linearization of function absorbance vs. concentration of atomic vapor and integration of thus modified absorbance at the resonance lines of the elements to be determined. Practical application shows that the method can be employed for the direct simultaneous determination of about 20 elements above microgram per liter level within 3–5 orders of the magnitude concentration range. The investigated sources of measurement errors are mainly associated with the atomization and vapor transportation problems, which are aggravated for the simultaneous release of major and minor sample constituents. Respective corrections concerning the selection of analytical lines, optimal sampling volume, matrix modification and cleaning of the atomizer have been introduced in the SMET AAS analytical technology. Under the optimized experimental conditions the calibration curves in Log-Log coordinates for all the investigated analytes in the single or multi-element reference solutions are approximated by the first order equations. The use of these equations as permanent characteristics of the setup enables instant quantification of Al, Ca, Co, Cr, Cu, Fe, Mg, Mn and Ni in the underground water

Low-resolution continuum source simultaneous multi-element electrothermal atomic absorption spectrometry: steps into practice

Energy Technology Data Exchange (ETDEWEB)

Katskov, Dmitri, E-mail: katskovda@tut.ac.za

2015-03-01

The theory and practical problems of continuum source simultaneous multi-element electrothermal atomic absorption spectrometry (SMET AAS) are discussed by the example of direct analysis of underground water. The experimental methodology is based on pulse vaporization of the sample in a fast heated graphite tube and measurement of transient absorption of continuum spectrum radiation from D{sub 2} and Xe lamps within 200–400 nm wavelengths range with a low resolution spectral instrument and linear charge-coupled device. The setup permits the acquisition of 200 spectra during 1 s atomization pulse. Respective data matrix absorbance vs wavelength/time is employed for the quantification of elements in the sample. The calculation algorithm developed includes broad band and continuum background correction, linearization of function absorbance vs. concentration of atomic vapor and integration of thus modified absorbance at the resonance lines of the elements to be determined. Practical application shows that the method can be employed for the direct simultaneous determination of about 20 elements above microgram per liter level within 3–5 orders of the magnitude concentration range. The investigated sources of measurement errors are mainly associated with the atomization and vapor transportation problems, which are aggravated for the simultaneous release of major and minor sample constituents. Respective corrections concerning the selection of analytical lines, optimal sampling volume, matrix modification and cleaning of the atomizer have been introduced in the SMET AAS analytical technology. Under the optimized experimental conditions the calibration curves in Log-Log coordinates for all the investigated analytes in the single or multi-element reference solutions are approximated by the first order equations. The use of these equations as permanent characteristics of the setup enables instant quantification of Al, Ca, Co, Cr, Cu, Fe, Mg, Mn and Ni in the underground

Process for separately recovering uranium, transuranium elements, and fission products of uranium from atomic reactor fuel

International Nuclear Information System (INIS)

Balal, A.L.; Metscher, K.; Muehlig, B.; Reichmuth, C.; Schwarz, B.; Zimen, K.E.

1976-01-01

Spent reactor fuel elements are dissolved in dilute nitric acid. After addition of acetic acid as a complexing agent, the nitric acid is partly decomposed and the mixture subjected to electrolysis while a carrier liquid, which may be dilute acetic acid or a dilute mixture of acetic acid and nitric acid is caused to flow in the electric field between the electrodes either against the direction of ion migration or transversely thereto. The ions of uranium, plutonium, and other transuranium elements, and of fission products accumulate in discrete portions of the electrolyte and are separately withdrawn as at least three fractions after one or more stages of electrolysis

Isolation of radioactive strontium from natural samples. Separation of strontium from alkaline and alkaline earth elements by means of mixed solvent anion exchange

International Nuclear Information System (INIS)

Grahek, Z.; Kosutic, K.; Lulic, S.; Kvastek, K.; Eskinja, I.

1999-01-01

This paper presents the results of studies which led to the procedures for the chromatographic separation of radioactive strontium from alkaline, earth-alkaline and other elements in natural samples, on columns filled with strong base anion exchangers using alcoholic solutions of nitric acid as eluents. It has been shown that potassium, caesium, calcium, barium, yttrium and strontium can be adsorbed on strong base anion exchangers of the Dowex and Amberlite type, which contain the quaternary ammonium group with nitrate as counter-ion, from solutions of nitric acid in alcohol. Adsorption strength increases in the order methanol 3 in methanol, while they are adsorbed from ethanol and propanol. The adsorption strength is influenced by the polarity of alcohol, by the concentration of nitrate and by pH. The strength with which strontium adsorbs on the exchangers increases in the interval from 0 to 0.25M NH 4 NO 3 in methanol, after which it starts to decrease. Strontium adsorbs to the exchangers from the alcoholic solution of ammonium nitrate twice as strongly as from the alcoholic solution of nitric acid, while a fraction of water in pure alcohol exceeding 10% prevents adsorption. In the mixture of alcohol and nitric acid, the adsorption strength for calcium and strontium increases with the increase of the volume fraction of alcohol with a lower dielectric constant. The rate and strength of adsorption of ions on the exchanger also increase in the series 0.25M HNO 3 in methanol 3 in ethanol 3 in 1-propanol for each individual ion, as well as in the Ca 3 in methanol, 0.25M HNO 3 in ethanol and 0.25M HNO 3 in propanol. Separation is also possible from alcohol mixtures. Strontium separation is most difficult from calcium, while the efficiency of separation increases with a decrease of the polarity of the used alcohol or alcohol mixture. The first group elements of the periodic table are not separated from each other in this way, while the elements of the second group are

Separation, preconcentration and estimation of rare earth and trace elements by inductively coupled plasma-atomic emission spectrometry (ICP-AES) in thorium matrices

International Nuclear Information System (INIS)

Chakraborty, Prithwish; Kumar Vijay; Durani, Smeer; Satyanarayana, K.

2007-01-01

A simple, sensitive and efficient method is developed for the separation of Rare earth elements (REEs) La-Lu, and Y and some trace elements Cd, Co, Cr, Cu, Ni,V, Zn from thorium matrix and their subsequent estimations by ICP-AES. In thorium-rich geological samples, the estimation of REE's by ICP-AES suffers from the spectral interferences due to the presence of excess of Th. In the proposed method, thorium is separated from the matrix by the solvent extraction. To optimize the separation, of REEs and trace elements from Th matrix, synthetic mixture solutions was prepared containing Th, REEs and trace elements maintaining different acidic conditions (1M, 2M, 4M, 6M, 8M and 10M HNO 3 and 2M, 4M, 6M and 8M HCl) and each solution was subjected to solvent extraction. The solvent extraction was carried out using a mixture of di-2-ethylhexyl phosphoric acid (in 30 % Toluene) and 1- pentanol in the ratio of 5:1. The aqueous phase containing the required elements was evaporated to dryness and an acidity of 5% HCl is maintained in final volume. Solutions were analysed by ICP-AES and the quantitative recovery of REEs and trace elements were obtained at 6M HNO 3 acidity. The developed method was applied to the certified standard reference material: IGS-36 and the values obtained were comparable with the certified values. The method was also applied to the real time monazite sample and the recovery was quantitative. Corrections have been applied for the REEs inter-elemental interferences in ICP-AES. (author)

Separation of macro-quantities of actinide elements at Savannah River by high-pressure cation exchange

International Nuclear Information System (INIS)

Burney, G.A.

1980-01-01

Large-scale separation of actinides from fission products and from each other by pressurized cation exchange chromatography at Savannah River is reviewed. Several kilograms of 244 Cm have been separated, with each run containing as much as 150 g of 244 Cm. Dowex 50W-X8 (Dow Chemical Co.) cation resin, graded to 30-70 micron size range, is used, and separation is made by eluting with 0.05M diethylenetriamine pentaacetic acid (DTPA) at a pH of 3. The effluent from the column is continuously monitored by a BF 3 detector, a NaI detector, and a lithium-drifted germanium detector and gamma spectrometer to guide collection of product fractions. Operating the columns at 300 to 1000 psi pressure eliminates resin bed disruption caused by radiolytically produced gases, and operating at increased flow rates decreases the radiolytic degradation of the resin per unit of product processed. A portion of the hot canyon of a production radiochemical separation plant was converted from a remote crane-operated facility to a master-slave manipulator-operated facility for separation and purification of actinide elements by pressurized cation exchange. It also contains an evaporator, furnaces, a calorimeter, and several precipitators and associated tanks. Actinide processing from target dissolution to packaging of purified product is planned in this facility

On the accuracy of X-ray lithography using synchrotron radiation for the fabrication of technical separation nozzle elements

International Nuclear Information System (INIS)

Becker, E.W.; Ehrfeld, W.; Muenchmeyer, D.

1984-04-01

As a method for the fabrication of technical separation nozzle elements with extremely small characteristic dimensions, the Institut fuer Kernverfahrenstechnik of the University and the Nuclear Research Centre of Karlsruhe in co-operation with the Siemens AG, Munich, and the Fraunhofer Institute for Solid-State Technology, Munich, are developping the LIGA-process. In this process, poly(methylmethacrylate) layers of an approximate thickness of 0.5 mm are structured by means of X-ray depth-lithography using synchrotron radiation. Subsequently, the nozzle structures are electroformed with nickel using the PMMA-layers as a mould. The manufacturing precision which can be obtained by X-ray depth-lithography was investigated by means of computer simulation of both the irradiation and the development step. In the first step the precision is limited by diffraction, photoelectrons, and beam divergency, respectively. It is shown, that under appropriate conditions each of these effects contributes only some 0.1 μm to errors at the structure edges. The simulation of the development step is based on experiments on the dissolution properties of both irradiated and unirradiated PMMA in a special developing agent. From the results of the computer simulation it can be seen, that the ratio of the slit length to the smallest width which is required for the fabrication of separation nozzles and the required precision are already obtainable in the one-step lithographic process at a characteristic wavelength of 0.2 nm. If an extreme structure height in combination with high precision is required or if a radiation source with a longer characteristic wavelength has to be used, the multi-step process can be applied. The calculations may easily be adapted to different manufacturing parameters concerning the radiation source or the developer characteristic. (orig.) [de

Determination of multi-element in marine sediment samples collected in Angola by the k0-NAA technique

International Nuclear Information System (INIS)

Teixeira, M.C.P.; Ho Manh Dung; Cao Dong Vu; Nguyen Thi Sy; Nguyen Thanh Binh; Vuong Huu Tan

2006-01-01

The marine sediment samples were designed to collect in Angola for marine environmental pollution study. The k 0 -standardization method of neutron activation analysis (k 0 -NAA) on Dalat research reactor has been developed to determine of multi-element in the Angola marine sediment samples. The samples were irradiated in cell 7-1 for short- and middle-lived nuclides and rotary specimen rack for long-lived nuclides. The irradiation facilities were characterized for neutron spectrum parameters and post-activated samples were measured on the calibrated gamma-ray spectrometers using HPGe detectors. The analytical results for 9 marine sediment samples with 27 elements: Al, As, Br, Ca, Ce,Cl, Co, Cs, Dy, Fe, Hf, I, K, Mg, Mn, Na, Rb, Sb, Sc, Se, Sm, Th, Ti, U, V and Zn in term of mean concentration, standard deviation and their content range are shown in the report. The analytical quality assurance was done by analysis of a Japan's certified reference material namely marine sediment NMIJ-CRM-7302a. These preliminary results revealed that the k 0 -NAA technique on the Dalat research reactor is a good analytical technique for determination of multi-element in the marine sediment samples. Some heavy metals and trace elements determined in this work possibly connected to the human activities at the sampling region. (author)

Multi-Directional Environmental Sensors

Science.gov (United States)

Manohara, Harish (Inventor); Del Castillo, Linda Y. (Inventor); Mojarradi, Mohammed M. (Inventor)

2016-01-01

Systems and methods in accordance with embodiments of the invention implement multi-directional environmental sensors. In one embodiment, a multi-directional environmental sensor includes: an inner conductive element that is substantially symmetrical about three orthogonal planes; an outer conductive element that is substantially symmetrical about three orthogonal planes; and a device that measures the electrical characteristics of the multi-directional environmental sensor, the device having a first terminal and a second terminal; where the inner conductive element is substantially enclosed within the outer conductive element; where the inner conductive element is electrically coupled to the first terminal of the device; and where the outer conductive element is electrically coupled to the second terminal of the device.

Separation of zirconium and hafnium from acompanying elements by paper chromatography in the systems of alcohol-acid

International Nuclear Information System (INIS)

Lebedeva, G.G.; Viktorova, M.E.

1980-01-01

Solvents have been chosen and investigated which provide expressed separation of zirconium and hafnium at the analysis of mineral raw materials by paper chromatography. The systems with HNO 3 and HCl containing methyl, ethyl, propyl and butyl alcohols have been studied as mobile phases for separation of zirconium and hafnium. It has been shown that alcohol contents and solvent acidity affect the Rsub(f) value of these elements. The C 2 H 5 OH-5MHCl and C 2 H 5 OH-5MHNO 3 systems are most optimal for pre-concentration of zirconium and hafnium

A simple chemical method for the separation of phosphorus interfering the trace element determinations by neutron activation analysis in high doped silicon wafers

International Nuclear Information System (INIS)

Wagler, H.; Flachowsky, J.

1986-01-01

Neutron activation analysis is one of the most available method for the determination of trace elements, but in the case of P-doped silicon wafers the 32 P-activity interferes the gamma spectrometry. It is not possible to determine the trace elements without chemical manipulations. On the other hand, time consuming chemical separations should be avoided. Therefore, a simple and rapid P-separation method has to be developed, in which the following twelve trace elements should be taken into consideration: Ag, As, Au, Co, Cr, Cu, Fe, Mo, Na, Sb, W, and Zn. After acid oxidative dissolution of the activated sample, P is present as phosphate ion. The phosphate ion is removed by precipitation as BiPO 4 . (author)

Chemistry of superheavy elements

International Nuclear Information System (INIS)

Schaedel, M.

2012-01-01

The chemistry of superheavy elements - or transactinides from their position in the Periodic Table - is summarized. After giving an overview over historical developments, nuclear aspects about synthesis of neutron-rich isotopes of these elements, produced in hot-fusion reactions, and their nuclear decay properties are briefly mentioned. Specific requirements to cope with the one-atom-at-a-time situation in automated chemical separations and recent developments in aqueous-phase and gas-phase chemistry are presented. Exciting, current developments, first applications, and future prospects of chemical separations behind physical recoil separators ('pre-separator') are discussed in detail. The status of our current knowledge about the chemistry of rutherfordium (Rf, element 104), dubnium (Db, element 105), seaborgium (Sg, element 106), bohrium (Bh, element 107), hassium (Hs, element 108), copernicium (Cn, element 112), and element 114 is discussed from an experimental point of view. Recent results are emphasized and compared with empirical extrapolations and with fully-relativistic theoretical calculations, especially also under the aspect of the architecture of the Periodic Table. (orig.)

Feasibility Studies for Production of Pellet Grade Concentrate from Sub Grade Iron Ore Using Multi Gravity Separator

Science.gov (United States)

Rao, Gottumukkala Venkateswara; Markandeya, R.; Kumar, Rajan

2018-04-01

An attempt has been made to utilise Sub Grade Iron Ore by producing pellet grade concentrate from Deposit 5, Bacheli Complex, Bailadila, Chhattisgarh, India. The `as received' Run of Mine (ROM) sample assayed 40.80% Fe, 40.90% SiO2. Mineralogical studies indicated that the main ore mineral is Hematite and lone gangue mineral is Quartz. Mineral liberation studies indicated that, the ore mineral Hematite and gangue mineral Quartz are getting liberated below 100 microns. The stage crushed and ground sample was subjected to concentration by using a Multi Gravity Separator (MGS). Rougher Multi Gravity Separation (MGS) experimental results were optimised to recover highest possible iron values. A concentrate of 55.80% Fe with a yield of 61.73% by weight with a recovery of 84.42% Iron values was obtained in rougher MGS concentrate. Further experiments were carried out with rougher MGS concentrate to produce a concentrate suitable for commercial grade pellet concentrate. It was proved that a concentrate assaying 66.67% Fe, 3.12% SiO2 with an yield of 45.08% by weight and with a recovery of 73.67% iron values in the concentrate.

Radio elements / bottom salts separation by nano-filtration aided by complexation in a highly saline environment

International Nuclear Information System (INIS)

Gaubert, Eric

1997-01-01

This research thesis addresses the use of a membrane-based technique, nano-filtration, aided or not by complexation, for the processing of highly saline liquid effluents produced by radio-chemical decontamination. The objective is to separate non-radioactive elements (sodium nitrate) from radio-elements (caesium, strontium and actinides) in order to reduce the volume of wastes. Within the perspective of an industrial application, a system to concentrate the effluent is firstly defined. Different nano-filtration membranes are tested and reveal to be insufficient in highly saline environment. A stage of selective complexation of radio-elements is therefore considered before nano-filtration. The main factors affecting performance of nano-filtration-complexation (for a given membrane system) are identified: ionic force, pH, ligand content, trans-membrane pressure. Finally, a nano-filtration pilot is implemented to perform nano-filtration-complexation operations by remote handling on radioactive substances [fr

The multi-element ultrasonic technology: examples of application on military naval structures

International Nuclear Information System (INIS)

Recolin, P.; Rivalin, S.

2009-01-01

DCNS is the European leader in the military ship construction and maintenance (conventional and nuclear propulsion). The potential of ultrasonic technologies with multi-element probes has been studied in its Materials laboratory since the end of the 80's, and a growing number of applications has appeared these last ten years. A series of examples is given: in-service nuclear reactor pipe welds monitoring, time-of-flight diffraction (TOFD) technique for the inspection of containment welds, coating fabrication control, detection of laminating corrosion on aluminum rings, detection of corrosion on submarine hulls in basin, inspection of hull welded joints

Studies on rapid ion-exchange separation of the transplutonium elements with mineral acid-methanol mixed media

International Nuclear Information System (INIS)

Usuda, Shigekazu

1989-03-01

In order to study properties of short-lived transplutonium nuclides synthesized by heavy-ion bombardment, three methods for rapid separation of tri-valent transplutonium elements by ion-exchange chromatography with mineral acid-methanol mixed media at elevated temperature were investigated. The first separation method was anion-exchange chromatography with nitric acid-methanol mixed media. The second method was anion-exchange choromatography with dilute hydrochloric acid-methanol mixed media. The third method was improved cation-exchange chromatography with single-column operation using the mixed media of hydrochloric acid and methanol. The separation methods developed were found applicable to studies on synthesis of the trans-plutonium nuclides, 250 Fm (T 1/2 :30 min), 244,245,246 Cf (T 1/2 :20 min, 46 min and 35.7 h, respectively) from the 16 O + 238 U and 12 C + 242 Pu reactions, and on the decay property of 245 Cf. Attempts to search for new actinide nuclides, such as 240 U and neutron deficient nuclides of Am, Cm and Bk, were made by a quick purification. The separation system was also applied to the rapid and effective separation of Nd, Am and Cm from spent nuclear fuel samples, for burn-up determination. (J.P.N.) 242 refs

Homogenization on Multi-Materials’ Elements: Application to Printed Circuit Boards and Warpage Analysis

Directory of Open Access Journals (Sweden)

Araújo Manuel

2016-01-01

Full Text Available Multi-material domains are often found in industrial applications. Modelling them can be computationally very expensive due to meshing requirements. The finite element properties comprising different materials are hardly accurate. In this work, a new homogenization method that simplifies the computation of the homogenized Young modulus, Poisson ratio and thermal expansion coefficient is proposed, and applied to composite-like material on a printed circuit board. The results show a good properties correspondence between the homogenized domain and the real geometry simulation.

A computer programme for use in the development of multi-element x-ray-fluorescence methods of analysis

International Nuclear Information System (INIS)

Wall, G.J.

1985-01-01

A computer programme (written in BASIC) is described for the evaluation of spectral-line intensities in X-ray-fluorescence spectrometry. The programme is designed to assist the analyst while he is developing new analytical methods, because it facilitates the selection of the following evaluation parameters: calculation models, spectral-line correction factors, calibration curves, calibration ranges, and point deletions. In addition, the programme enables the analyst to undertake routine calculations of data from multi-element analyses in which variable data-reduction parameters are used for each element

Optimisation of a Multi-Gravity Separator with Novel Modifications for the Recovery of Ferberite

Directory of Open Access Journals (Sweden)

Robert Fitzpatrick

2018-05-01

Full Text Available Tungsten is considered by the European Union as a critical raw material for future development due to its expected demand and scarcity of resource within Europe. It is therefore, critical to optimize European tungsten operations and maximise recoveries. The role of enhanced gravity/centrifugal concentrators in recovering tungsten from ultra-fine fractions should form an important part of this aim. Reported herein are the results of investigations to improve efficiency of Wolf Minerals’ Draklends mine, a major European tungsten mine, by recovering saleable material from a magnetic waste stream of a low-intensity magnetic separator using an enhanced gravity concentrator. The mine hosts wolframite and ferberite as the main tungsten bearing mineral species. A Mozley multi-gravity separator (MGS C-900 was selected as it is suited to exploiting small variations in mineral density to affect a separation. Working with a current manufacturer, a novel scraping blade system was tested. To assess the MGS in a statistically valid manner, a response surface methodology was followed to determine optimal test conditions. The test programme showed that the most important parameters were drum speed and wash water rate. Under optimal conditions the model predicted that 40% of the tungsten could be recovered above the required grade of 43% WO3.

Method of separating plutonium from the process streams of a reprocessing plant for HTR fuel elements

Energy Technology Data Exchange (ETDEWEB)

Herz, D.; Kankura, R.; Wenzel, U.

1975-07-15

The process streams of a reprocessing plant for Th-U fuel elements can be purified of Pu, using a chromatographic method. The process is based on the principles of extraction chromatography with the application of the method of breakthrough chromatography. The inert carrier consists of polytrifluoromonochloroethylene, TOA forming the steady-state phase and 2 M HNO/sub 3/ the mobile phase. After adjustment of the feed solution to the extraction conditions, Pu is extracted in the separating column to the steady-state phase. The height of the separating stages is expressed by the equation HTS (cm) = 0.2 + 0.65 u/sub 0/ (cm min/sup -1/). Due to the delayed Pu/Th exchange in TOA, it depends heavily on the linear flow velocity. Details are given of the design of a separating unit for a flowrate of 2 kg of heavy metal per day (the flowrate of the Jupiter plant). (12 fig, 4 tables)

Non destructive multi elemental analysis using prompt gamma neutron activation analysis techniques: Preliminary results for concrete sample

Energy Technology Data Exchange (ETDEWEB)

Dahing, Lahasen Normanshah [School of Applied Physics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia and Malaysian Nuclear Agency (Nuklear Malaysia), Bangi 43000, Kajang (Malaysia); Yahya, Redzuan [School of Applied Physics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Yahya, Roslan; Hassan, Hearie [Malaysian Nuclear Agency (Nuklear Malaysia), Bangi 43000, Kajang (Malaysia)

2014-09-03

In this study, principle of prompt gamma neutron activation analysis has been used as a technique to determine the elements in the sample. The system consists of collimated isotopic neutron source, Cf-252 with HPGe detector and Multichannel Analysis (MCA). Concrete with size of 10×10×10 cm{sup 3} and 15×15×15 cm{sup 3} were analysed as sample. When neutrons enter and interact with elements in the concrete, the neutron capture reaction will occur and produce characteristic prompt gamma ray of the elements. The preliminary result of this study demonstrate the major element in the concrete was determined such as Si, Mg, Ca, Al, Fe and H as well as others element, such as Cl by analysis the gamma ray lines respectively. The results obtained were compared with NAA and XRF techniques as a part of reference and validation. The potential and the capability of neutron induced prompt gamma as tool for multi elemental analysis qualitatively to identify the elements present in the concrete sample discussed.

Mass separation of rare-earth elements by a high-temperature thermal ion source coupled with a He-jet system

International Nuclear Information System (INIS)

Kawase, Y.; Okano, K.; Aoki, K.

1987-01-01

By using a high-temperature thermal ion source coupled to a He-jet system, neutron-rich isotopes of rare-earth elements such as cerium, praseodymium, neodymium and promethium produced by the thermal-neutron fission of /sup 235/U were ionized and successfully separated. The temperature dependence of the ionization efficiency has been measured and found to be explained qualitatively by the vapour pressure of the relevant elements. The characteristic temperature dependence of the ionization efficiency has been utilized for Z-identification of several isobars of rare-earth elements. The heaviest isotopes of neodymium and promethium, /sup 155/Nd and /sup 156/Pm, have recently been identified

Element separation before matter accretion of solar system planets in the light of the periodic law

International Nuclear Information System (INIS)

Chuburkov, Yu.T.

1990-01-01

The proofs of element separation in protoplanet nebula of Protosolar system have been found. For this purpose the K 1 /K 2 ratios of concentration of elements - chemical analogs in the rock samples of Venus, Earth, Mars and meteorites were compared. The new approach enabled the comparison of K 1 /K 2 of the Earth and meteorites with K 1 /K 2 of Venus and Mars obtained by elemental analysis of their rock samples. It has been found that at J 2 /J 1 >1 chemical analogs have K 1 /K 2 : on Venus probably less or at least commeasurable, on Mars and, especially in meteorites, considerably (several orders of magnitude) greater than in the Earth rocks (J 1 and J 2 are charged atoms fractions in photon flux of the Protosun). Other facts, which agree with the relationship K 1 /K 2 =f(R), where R is the average distance of a body from the Sun, were found. 41 refs.; 1 fig.; 5 tabs

Isotope separation

International Nuclear Information System (INIS)

Bartlett, R.J.; Morrey, J.R.

1978-01-01

A method and apparatus is described for separating gas molecules containing one isotope of an element from gas molecules containing other isotopes of the same element in which all of the molecules of the gas are at the same electronic state in their ground state. Gas molecules in a gas stream containing one of the isotopes are selectively excited to a different electronic state while leaving the other gas molecules in their original ground state. Gas molecules containing one of the isotopes are then deflected from the other gas molecules in the stream and thus physically separated

A fast pointwise strategy for anisotropic wave-mode separation in TI media

KAUST Repository

Liu, Qiancheng

2017-08-17

The multi-component wavefield contains both compressional and shear waves. Separating wave-modes has many applications in seismic workflows. Conventionally, anisotropic wave-mode separation is implemented by either directly filtering in the wavenumber domain or nonstationary filtering in the space domain, which are computationally expensive. These methods could be categorized into the pseudo-derivative family and only work well within Finite Difference (FD) methods. In this paper, we establish a relationship between group-velocity direction and polarity direction and propose a method, which could go beyond modeling by FD. In particular, we are interested in performing wave-mode separation in a Spectral Element Method (SEM), which is widely used for seismic wave propagation on various scales. The separation is implemented pointwise, independent of its neighbor points, suitable for running in parallel. Moreover, no correction for amplitude and phase changes caused by the derivative operator is required. We have verified our scheme using numerical examples.

A fast pointwise strategy for anisotropic wave-mode separation in TI media

KAUST Repository

Liu, Qiancheng; Peter, Daniel; Lu, Yongming

2017-01-01

The multi-component wavefield contains both compressional and shear waves. Separating wave-modes has many applications in seismic workflows. Conventionally, anisotropic wave-mode separation is implemented by either directly filtering in the wavenumber domain or nonstationary filtering in the space domain, which are computationally expensive. These methods could be categorized into the pseudo-derivative family and only work well within Finite Difference (FD) methods. In this paper, we establish a relationship between group-velocity direction and polarity direction and propose a method, which could go beyond modeling by FD. In particular, we are interested in performing wave-mode separation in a Spectral Element Method (SEM), which is widely used for seismic wave propagation on various scales. The separation is implemented pointwise, independent of its neighbor points, suitable for running in parallel. Moreover, no correction for amplitude and phase changes caused by the derivative operator is required. We have verified our scheme using numerical examples.

NanoSIMS multi-element imaging reveals internalisation and nucleolar targeting for a highly-charged polynuclear platinum compound.

Science.gov (United States)

Wedlock, Louise E; Kilburn, Matt R; Liu, Rong; Shaw, Jeremy A; Berners-Price, Susan J; Farrell, Nicholas P

2013-08-11

Simultaneous multi-element imaging using NanoSIMS (nano-scale secondary ion mass spectrometry), exploiting the novel combination of (195)Pt and (15)N in platinum-am(m)ine antitumour drugs, provides information on the internalisation and subcellular localisation of both metal and ligands, and allows identification of ligand exchange.

A nonlinear multi-proxy model based on manifold learning to reconstruct water temperature from high resolution trace element profiles in biogenic carbonates

Directory of Open Access Journals (Sweden)

M. Bauwens

2010-11-01

Full Text Available A long standing problem in paleoceanography concerns the reconstruction of water temperature from δ¹⁸O carbonate. It is problematic in the case of freshwater influenced environments because the δ¹⁸O isotopic composition of the ambient water (related to salinity needs to be known. In this paper we argue for the use of a nonlinear multi-proxy method called Weight Determination by Manifold Regularization (WDMR to develop a temperature reconstruction model that is less sensitive to salinity variations. The motivation for using this type of model is twofold: firstly, observed nonlinear relations between specific proxies and water temperature motivate the use of nonlinear models. Secondly, the use of multi-proxy models enables salinity related variations of a given temperature proxy to be explained by salinity-related information carried by a separate proxy. Our findings confirm that Mg/Ca is a powerful paleothermometer and highlight that reconstruction performance based on this proxy is improved significantly by combining its information with the information for other trace elements in multi-proxy models. Although the models presented here are black-box models that do not use any prior knowledge about the proxies, the comparison of model reconstruction performances based on different proxy combinations do yield useful information about proxy characteristics. Using Mg/Ca, Sr/Ca, Ba/Ca and Pb/Ca the WDMR model enables a temperature reconstruction with a root mean squared error of ± 2.19 °C for a salinity range between 15 and 32.

Bk and Cf chromatographic separation and 249Bk/248Cm and 249Cf/248Cm elemental ratios determination by inductively coupled plasma quadrupole mass spectrometry

International Nuclear Information System (INIS)

Gourgiotis, A.; Isnard, H.; Nonell, A.; Aubert, M.; Stadelmann, G.; Dupont, E.; AlMahamid, I.; Tiang, G.; Rao, L.; Lukens, W.; Cassette, P.; Panebianco, S.; Letourneau, A.; Chartier, F.

2013-01-01

The French Atomic Energy Commission has carried out several experiments for the study of minor-actinide transmutation processes in high intensity thermal neutron flux. In this context a Cm sample enriched in 248 Cm (97%) was irradiated in a thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). The precise and accurate determination of Cf isotope ratios and of 249 Bk/ 248 Cm and 249 Cf/ 248 Cm elemental ratios in the 248 Cm irradiated sample is crucial for the calculation of actinide neutron capture cross-sections.This work describes an analytical procedure for the separation and the isotope ratio measurement of Bk and Cf in the irradiated sample.The Bk and Cf separation is based on a lanthanides separation protocol previously developed by the laboratory. Well-defined retention times for Bk and Cf were obtained by coupling the Ionic Chromatography (IC) with an ICP-QMS. All conditions of element separation by IC and the different steps of the analytical protocol in order to obtain the isotopic and elemental ratios are presented. Relative uncertainties of Cf isotopic ratios range from 0.3% to 0.5% and the uncertainty of the 249 Bk/ 248 Cm and 249 Cf/ 248 Cm elemental ratios are respectively 6.1% and 3.2%.This level of uncertainty for both isotopic and elemental ratios is in perfect agreement with the requirement for transmutation studies. (authors)

Application of the multi-element analysis by X-fluorescence and neutron activation to the characterization of an archaeological site

International Nuclear Information System (INIS)

Rossini, I.

1991-06-01

The first part of this thesis is about possible analysis methods (XRF, PIXE, INAA, laser fluorimetry, and ICP), applied to Uranium, Thorium and Rubidium assays in archaeological clays and potteries. The best results have been obtained with Neutron Activation technics. The second part is about the multi-element analysis of quarries and about the research by statistical treatment of correlations between the element concentrations and the sampling sites (excavations, quarries)

Quantification of trace elements in protein bands by synchrotron radiation x-ray fluorescence after isoelectric focusing separation of human hemoglobin

International Nuclear Information System (INIS)

Gao Yuxi; Chen Chunying; Li Bai; He Wei; Huang Yuying; Chai Zhifang

2005-01-01

The role and effects of a trace element in a particular organism strongly depend on its particular chemical forms in which the element is present. Therefore, the bulk content or concentration of an element in the organism of interest is often meaningless in judging its biological significance. To understand bioavailability, transportation, cell uptake, metabolism, toxicity, and other biological behaviors of trace elements in the body, information is needed about speciation of trace element, especially about distribution of metal-containing proteins. Development of appropriate methods for speciation analysis is therefore required. Synchrotron radiation x-ray fluorescence (SRXRF) is a sensitive method for multielemental analysis with detection limit of 10 ng/g. It has been successfully used for imaging and quantifying trace elements in various pathological and healthy tissues, even in a single cell, to help understand the mechanism of diseases and the biochemistry of elements. In our previous work, the technique was combined with electrophoresis to study distribution of metalloproteins in biological samples, but the quantitative analysis of trace elements in protein bands after electrophoresis was still unrealized. In this study, a procedure has been proposed for quantification of Fe, Cu, and Zn in protein bands with SRXRF analysis after isoelectric focusing (IEF) separation. Calibration standards were prepared by adding certain amounts of metal ions and free-metal proteins to electrophoresis gel. Human hemoglobin was separated with IEF, and Fe, Cu, and Zn in protein bands were analyzed by SRXRF. The calibration curves can be obtained in a range of 0-8 mg/kg metals and a linear relationship between dosage of metals and fluorescent intensity can be observed (r 2 > 0.99). The method provides the detection limits of 2.43, 1.12, and 0.96 mg/kg for Fe, Cu and Zn, and the recoveries of 90.4 and 115.7 % for Fe and Zn, respectively. The hyphenated technique of SRXRF and IEF

Quantitative and qualitative analysis of fluoride and multi elements of shark teeth by PIXE

International Nuclear Information System (INIS)

Sakurai, S.; Asakawa, R.; Hirota, F.; Sato, T.; Sera, K.; Itoh, J.

2008-01-01

Biomineralization has two types, biologically induced mineralization (BIM) and biologically controlled mineralization (BCM). Shark teeth is a typical representative of BCM. We have measured concentrations of fluorine and multi elements in shark teeth collected in the south of Japan. As a result, it was confirmed that the sample preparation method, which was established for the biological samples, is applicable to the shark teeth samples and the elemental concentration was obtained in good accuracy and reproducibility. Moreover, we clarified that the shark teeth is composed of Fluorapatite by the combination with X-ray Diffraction. Fluorine concentration is found to be 5500 μg/g in the shark teeth. We have 100 samples of Shark teeth and are planning on reporting the findings of a study with larger samples in the near future. (author)

Use of multi-frequency, multi-polarization, multi-angle airborne radars for class discrimination in a southern temperature forest

Science.gov (United States)

Mehta, N. C.

1984-01-01

The utility of radar scatterometers for discrimination and characterization of natural vegetation was investigated. Backscatter measurements were acquired with airborne multi-frequency, multi-polarization, multi-angle radar scatterometers over a test site in a southern temperate forest. Separability between ground cover classes was studied using a two-class separability measure. Very good separability is achieved between most classes. Longer wavelength is useful in separating trees from non-tree classes, while shorter wavelength and cross polarization are helpful for discrimination among tree classes. Using the maximum likelihood classifier, 50% overall classification accuracy is achieved using a single, short-wavelength scatterometer channel. Addition of multiple incidence angles and another radar band improves classification accuracy by 20% and 50%, respectively, over the single channel accuracy. Incorporation of a third radar band seems redundant for vegetation classification. Vertical transmit polarization is critically important for all classes.

Simultaneous multi-element determination in different seed samples of Dodonaea viscosa hopseed using instrumental neutron activation analysis

International Nuclear Information System (INIS)

El-Sweify, Fatma H.; El-Amir, Mahmoud A.; Mostafa, Mohamed; Ramadan, Hala E.; Rashad, Ghada M.

2016-01-01

Instrumental neutron activation analysis technique (INAA) was applied for nondestructive multi-element analysis of seed samples of the plant Dodonaea viscosa hopseed. This plant is distributed all over Egypt, because of its suitable properties. The samples were collected from some bushes grown at different sites in some governorates, in July of each year during the period from 2004 to 2011. The determined elements are: Co, Cs, Eu, Fe, Hg, Ni, Rb, Sc, Se, Sr and Zn, under the chosen irradiation and cooling times. The content of some elements has been compared with data obtained from previous work on analysis of various kinds of seeds. The influence of some parameters on the determined elemental content is discussed. Standard reference materials IAEA-155 and IAEA-V-10 were used to assure quality control, accuracy and precision of the technique.

Simultaneous multi-element determination in different seed samples of Dodonaea viscosa hopseed using instrumental neutron activation analysis

Energy Technology Data Exchange (ETDEWEB)

El-Sweify, Fatma H.; El-Amir, Mahmoud A.; Mostafa, Mohamed; Ramadan, Hala E.; Rashad, Ghada M. [Atomic Energy Authority, Cairo (Egypt). Hot Lab. Center

2016-07-01

Instrumental neutron activation analysis technique (INAA) was applied for nondestructive multi-element analysis of seed samples of the plant Dodonaea viscosa hopseed. This plant is distributed all over Egypt, because of its suitable properties. The samples were collected from some bushes grown at different sites in some governorates, in July of each year during the period from 2004 to 2011. The determined elements are: Co, Cs, Eu, Fe, Hg, Ni, Rb, Sc, Se, Sr and Zn, under the chosen irradiation and cooling times. The content of some elements has been compared with data obtained from previous work on analysis of various kinds of seeds. The influence of some parameters on the determined elemental content is discussed. Standard reference materials IAEA-155 and IAEA-V-10 were used to assure quality control, accuracy and precision of the technique.

Rapid methods for multi-elemental X-ray fluorescence analysis using excitation isotope sources and Si(Li)-semiconductor detector

International Nuclear Information System (INIS)

Zhuravleva, E.L.

1980-01-01

Some rapid methods using an unique calibration curve have been developed for multi-elemental X-ray fluorescence analysis of thin and thick layers of various samples having low contents of heavy elements. The matrix absorption effect in thick samples is taken into account according to the scattered radiation.The similar method using a unique calibration curve for determination of low contents of trace elements in thin layers without account of matrix effect is proposed. The results on the intercomposition run soil-5 are in good agreement with the data obtained in different laboratories. The errors of the method are 10 %; in a case of peak superposition - 15 %

Multi-reception strategy with improved SNR for multichannel MR imaging.

Directory of Open Access Journals (Sweden)

Bing Wu

Full Text Available A multi-reception strategy with extended GRAPPA is proposed in this work to improve MR imaging performance at ultra-high field MR systems with limited receiver channels. In this method, coil elements are separated to two or more groups under appropriate grouping criteria. Those groups are enabled in sequence for imaging first, and then parallel acquisition is performed to compensate for the redundant scan time caused by the multiple receptions. To efficiently reconstruct the data acquired from elements of each group, a specific extended GRAPPA was developed. This approach was evaluated by using a 16-element head array on a 7 Tesla whole-body MRI scanner with 8 receive channels. The in-vivo experiments demonstrate that with the same scan time, the 16-element array with twice receptions and acceleration rate of 2 can achieve significant SNR gain in the periphery area of the brain and keep nearly the same SNR in the center area over an eight-element array, which indicates the proposed multi-reception strategy and extended GRAPPA are feasible to improve image quality for MRI systems with limited receive channels. This study also suggests that it is advantageous for a MR system with N receiver channels to utilize a coil array with more than N elements if an appropriate acquisition strategy is applied.

Isotope separation process

International Nuclear Information System (INIS)

Thomas, W.R.L.

1979-01-01

The instant invention relates to an improved process for separating a material into two or more parts in each of which the abundances of the isotopes of a given element differ from the abundances of the isotopes of the same element in said material. More particularly, the invention relates to a method for the isotopically selective excitation of gas phase molecules by multiple infrared photon absorption followed by a step wherein more of the excited molecules than non-excited molecules are converted to a chemically different form which may be separated by means known in the art. This invention is useful for, but not limited to, the separation of the principal isotopes of uranium

The effectiveness of various treatments in changing the nutrient status and bioavailability of risk elements in multi-element contaminated soil.

Science.gov (United States)

García-Sánchez, Mercedes; García-Romera, Inmaculada; Száková, Jiřina; Kaplan, Lukáš; Tlustoš, Pavel

2015-09-01

Potential changes in the mobility and bioavailability of risk and essential macro- and micro-elements achieved by adding various ameliorative materials were evaluated in a model pot experiment. Spring wheat (Triticum aestivum L.) was cultivated under controlled condition for 60 days in two soils, uncontaminated Chernozem and multi-element contaminated Fluvisol containing 4900 ± 200 mg/kg Zn, 35.4 ± 3.6 mg/kg Cd, and 3035 ± 26 mg/kg Pb. The treatments were all contained the same amount of sulfur and were as follows: (i) digestate from the anaerobic fermentation of biowaste, (ii) fly ash from wood chip combustion, and (iii) ammonium sulfate. Macro- and micro-nutrients Ca, Mg, K, Fe, Mn, Cu, P, and S, and risk elements Cd, Cr, Pb, and Zn were assayed in soil extracts with 0.11 mol/l solution of CH3COOH and in roots, shoots, and grain of wheat after 30 and 60 days of cultivation. Both digestate and fly ash increased levels of macro- and micro-nutrients as well as risk elements (especially Cd and Zn; the mobility of Pb decreased after 30 days of cultivation). The changes in element mobility in ammonium sulfate-treated soils appear to be due to both changes in soil pH level and inter-element interactions. Ammonium sulfate tended to be the most effective measure for increasing nutrient uptake by plants in Chernozem but with opposite pattern in Fluvisol. Changes in plant yield and element uptake in treated plants may have been associated with the higher proline content of wheat shoots cultivated in both soils compared to control. None of the treatments decreased uptake of risk elements by wheat plants in the extremely contaminated Fluvisol, and their accumulation in wheat grains significantly exceeded maximum permissible levels; these treatments cannot be used to enable cereal and other crop production in such soils. However, the combination of increased plant growth alongside unchanged element content in plant biomass in pots treated with digestate

Dose determination algorithms for a nearly tissue equivalent multi-element thermoluminescent dosimeter

International Nuclear Information System (INIS)

Moscovitch, M.; Chamberlain, J.; Velbeck, K.J.

1988-01-01

In a continuing effort to develop dosimetric systems that will enable reliable interpretation of dosimeter readings in terms of the absorbed dose or dose-equivalent, a new multi-element TL dosimeter assembly for Beta and Gamma dose monitoring has been designed. The radiation-sensitive volumes are four LiF-TLD elements, each covered by its own unique filter. For media-matching, care has been taken to employ nearly tissue equivalent filters of thicknesses of 1000 mg/cm 2 and 300 mg/cm 2 for deep dose and dose to the lens-of-the-eye measurements respectively. Only one metal filter (Cu) is employed to provide low energy photon discrimination. A Thin TL element (0.09 mm thick) is located behind an open window designed to improve the energy under-response to low energy beta rays and to provide closer estimate of the shallow dose equivalent. The deep and shallow dose equivalents are derived from the correlation of the response of the various TL elements to the above quantities through computations based on previously defined relationships obtained from experimental results. The theoretical formalization for the dose calculation algorithms is described in detail, and provides a useful methodology which can be applied to different tissue-equivalent dosimeter assemblies. Experimental data has been obtained by performing irradiation according to the specifications established by DOELAP, using 27 types of pure and mixed radiation fields including Cs-137 gamma rays, low energy photons down to 20 keV, Sr/Y-90, Uranium, and Tl-204 beta particles

Extraction and separation of Am and rare earth elements in HNO3 solution with P507-sulphonating kerosene

International Nuclear Information System (INIS)

Li Zhenhu; Jiao Rongzhou; Zhu Yongjun

1994-01-01

A study has been made of the extraction equilibrium of Am(III) and rare earth elements (III) in HNO 3 solution with P507-sulphonating kerosene. It has been found that this equilibrium depends on saponification ratio of P507, feed acidity, metal concentration as well as phase ratio. The extraction ability in order is La< Ce< Am< Pr< Nd< Sm. The model of distribution ratio has been founded. The agreement for calculated and experimental values of distribution ratio is fairly good. These values can be used to design the extraction and separation process of Am and rare earth elements

PIXE-based quantification of health-proactive trace elements in genetically transformed roots of a multi-medicinal plant, Sida acuta Burm.f

International Nuclear Information System (INIS)

Somanatha Jena; Lopamudra Sahu; Chand, P.K.; Ray, D.K.; Mishra, S.K.

2015-01-01

Inorganic element composition of genetically transformed hairy root cultures (HRCs) of a medicinal plant, Sida acuta was determined using PIXE technique. HRCs had a higher accumulation of pro-health trace elements compared to natural roots. It was estimated that < 160 g d.wt. of a selected rhizoclone could suffice to provide nearly all tested essential elements catering to per diem requirement of the human body. The ideal multi-elemental profile ushers a new possibility of integrating hairy root extracts in modern therapeutics ('rhizotherapy') as complementary medicine or a dietary nutraceutical supplement. (author)

Separation method for ions of elements of the III., IV., VI. and VIII. groups of periodical system

International Nuclear Information System (INIS)

Marhol, M.

1973-01-01

The method is presented of separating the ions of the elements of the periodic system groups III, IV, and VIII by ion exchangers. The ions are complex-bonded to a new type of ion exchanger consisting of the polycondensates of phenol with aldehydes or ketones and containing an atom of phosphorus, arsenic or antimony with an atom of sulphur or oxygen in a complex bond. The polymers of compounds containing a double bond, e.g., of butadiene, polyvinyl alcohol, polyethylene, polypropylene, and the compounds of styrene with fural may also be used for this purpose. The method is demonstrated on a case of uranium and heavy metal concentration and the separation thereof from waste waters. (L.K.)

Multi-Antenna Data Collector for Smart Metering Networks with Integrated Source Separation by Spatial Filtering

Science.gov (United States)

Quednau, Philipp; Trommer, Ralph; Schmidt, Lorenz-Peter

2016-03-01

Wireless transmission systems in smart metering networks share the advantage of lower installation costs due to the expandability of separate infrastructure but suffer from transmission problems. In this paper the issue of interference of wireless transmitted smart meter data with third party systems and data from other meters is investigated and an approach for solving the problem is presented. A multi-channel wireless m-bus receiver was developed to separate the desired data from unwanted interferers by spatial filtering. The according algorithms are presented and the influence of different antenna types on the spatial filtering is investigated. The performance of the spatial filtering is evaluated by extensive measurements in a realistic surrounding with several hundreds of active wireless m-bus transponders. These measurements correspond to the future environment for data-collectors as they took place in rural and urban areas with smart gas meters equipped with wireless m-bus transponders installed in almost all surrounding buildings.

Diversity and MIMO Performance Evaluation of Common Phase Center Multi Element Antenna Systems

Directory of Open Access Journals (Sweden)

V. Papamichael

2008-06-01

Full Text Available The diversity and Multiple Input Multiple Output (MIMO performance provided by common phase center multi element antenna (CPCMEA systems is evaluated using two practical methods which make use of the realized active element antenna patterns. These patterns include both the impact of the mutual coupling and the mismatch power loss at antenna ports. As a case study, two and four printed Inverted F Antenna (IFA systems are evaluated by means of Effective Diversity Gain (EDG and Capacity (C. EDG is measured in terms of the signal-to-noise ratio (SNR enhancement at a specific outage probability and in terms of the SNR reduction for achieving a desired average bit error rate (BER. The concept of receive antenna selection in MIMO systems is also investigated and the simulation results show a 43% improvement in the 1% outage C of a reconfigurable 2x2 MIMO system over a fixed 2x2 one.

Unified Modeling Language description of the object-oriented multi-scale adaptive finite element method for Step-and-Flash Imprint Lithography Simulations

International Nuclear Information System (INIS)

Paszynski, Maciej; Gurgul, Piotr; Sieniek, Marcin; Pardo, David

2010-01-01

In the first part of the paper we present the multi-scale simulation of the Step-and-Flash Imprint Lithography (SFIL), a modern patterning process. The simulation utilizes the hp adaptive Finite Element Method (hp-FEM) coupled with Molecular Statics (MS) model. Thus, we consider the multi-scale problem, with molecular statics applied in the areas of the mesh where the highest accuracy is required, and the continuous linear elasticity with thermal expansion coefficient applied in the remaining part of the domain. The degrees of freedom from macro-scale element's nodes located on the macro-scale side of the interface have been identified with particles from nano-scale elements located on the nano-scale side of the interface. In the second part of the paper we present Unified Modeling Language (UML) description of the resulting multi-scale application (hp-FEM coupled with MS). We investigated classical, procedural codes from the point of view of the object-oriented (O-O) programming paradigm. The discovered hierarchical structure of classes and algorithms makes the UML project as independent on the spatial dimension of the problem as possible. The O-O UML project was defined at an abstract level, independent on the programming language used.

Evaluation of pressed powders and thin section standards for multi-elemental analysis by conventional and micro-PIXE analysis

International Nuclear Information System (INIS)

Homma-Takeda, Shino; Iso, Hiroyuki; Ito, Masaki

2010-01-01

For multi-elemental analysis, various standards are used to quantify the elements consists of environmental and biological samples. In this paper two different configuration standards, pressed powders and thin section standards, were assessed for their purpose as standards by conventional and micro-PIXE analysis. Homogeneity of manganese, iron, zinc (Zn), copper and yttrium added to pressed powder standard materials were validated and the relative standard deviation (RSD) of the X-ray intensity of the standards was 2 area and the metal concentration was acceptable. (author)

Finite element modeling of temperature load effects on the vibration of local modes in multi-cable structures

Science.gov (United States)

Treyssède, Fabien

2018-01-01

Understanding thermal effects on the vibration of local (cable-dominant) modes in multi-cable structures is a complicated task. The main difficulty lies in the modification by temperature change of cable tensions, which are then undetermined. This paper applies a finite element procedure to investigate the effects of thermal loads on the linear dynamics of prestressed self-weighted multi-cable structures. Provided that boundary conditions are carefully handled, the discretization of cables with nonlinear curved beam elements can properly represent the thermoelastic behavior of cables as well as their linearized dynamics. A three-step procedure that aims to replace applied pretension forces with displacement continuity conditions is used. Despite an increase in the computational cost related to beam rotational degrees of freedom, such an approach has several advantages. Nonlinear beam finite elements are usually available in commercial codes. The overall method follows a thermoelastic geometrically non-linear analysis and hereby includes the main sources of non-linearities in multi-cable structures. The effects of cable bending stiffness, which can be significant, are also naturally accounted for. The accuracy of the numerical approach is assessed thanks to an analytical model for the vibration of a single inclined cable under temperature change. Then, the effects of thermal loads are investigated for two cable bridges, highlighting how natural frequencies can be affected by temperature. Although counterintuitive, a reverse relative change of natural frequency may occur for certain local modes. This phenomenon can be explained by two distinct mechanisms, one related to the physics intrinsic to cables and the other related to the thermal deflection of the superstructure. Numerical results show that cables cannot be isolated from the rest of the structure and the importance of modeling the whole structure for a quantitative analysis of temperature effects on the

Trials of separation of the rare-earth elements on the way of fractional precipitation of terephthalates

Energy Technology Data Exchange (ETDEWEB)

Brzyska, W. (Uniwersytet Marii Curie-Sklodowskiej, Lublin (Poland))

1980-01-01

A possibility of the rare-earth elements separation on the way of fractional precipitation of terephthalates in the presence of a complexing agent was studied. Selecting an appropriate quantity of the complexing agent, it is possible to obtain fractions differing in their composition. In the first fractions the light lanthanides accumulate, whereas in the last one accumulate Y and heavy lanthanides. The advantage of this method is that the terephthalic acid can be regenerated practically in 100%.

Applications of covalent organic frameworks (COFs): From gas storage and separation to drug delivery

Institute of Scientific and Technical Information of China (English)

Ming-Xue Wu; Ying-Wei Yang

2017-01-01

Covalent organic frameworks (COFs) are an emerging class of porous covalent organic structures whose backbones were composed of light elements (B,C,N,O,Si) and linked by robust covalent bonds to endow such material with desirable properties,i.e.,inherent porosity,well-defined pore aperture,ordered channel structure,large surface area,high stability,and multi-dimension.As expected,the abovementioned properties of COFs broaden the applications of this class of materials in various fields such as gas storage and separation,catalysis,optoelectronics,sensing,small molecules adsorption,and drug delivery.In this review,we outlined the synthesis of COFs and highlighted their applications ranging from the initial gas storage and separation to drug delivery.

Finite element analysis of multi-material models using a balancing domain decomposition method combined with the diagonal scaling preconditioner

International Nuclear Information System (INIS)

Ogino, Masao

2016-01-01

Actual problems in science and industrial applications are modeled by multi-materials and large-scale unstructured mesh, and the finite element analysis has been widely used to solve such problems on the parallel computer. However, for large-scale problems, the iterative methods for linear finite element equations suffer from slow or no convergence. Therefore, numerical methods having both robust convergence and scalable parallel efficiency are in great demand. The domain decomposition method is well known as an iterative substructuring method, and is an efficient approach for parallel finite element methods. Moreover, the balancing preconditioner achieves robust convergence. However, in case of problems consisting of very different materials, the convergence becomes bad. There are some research to solve this issue, however not suitable for cases of complex shape and composite materials. In this study, to improve convergence of the balancing preconditioner for multi-materials, a balancing preconditioner combined with the diagonal scaling preconditioner, called Scaled-BDD method, is proposed. Some numerical results are included which indicate that the proposed method has robust convergence for the number of subdomains and shows high performances compared with the original balancing preconditioner. (author)

COMPUTING EXPERIMENT FOR ASSESSMENT OF AERODYNAMIC CHARACTERISTICS OF SEPARATE ELEMENTS IN THE STRUCTURE OF THE FUSELAGE OF A HELICOPTER

Directory of Open Access Journals (Sweden)

V. A. Ivchin

2015-01-01

Full Text Available The present publication describes the calculation of helicopter fuselage aerodynamic characteristics and its separate elements, by computing experiment. On the basis of program commercial package CFX ANSYS the technique has been mastered and longitudinal and lateral characteristics of the helicopter fuselage on the various flight modes are calculated.

Separation of uranium and rare earth elements from Rirang ore leach solution by two-step precipitation

International Nuclear Information System (INIS)

Sradjono; Erni Rifandriyah, A.; Zahardi

1995-01-01

Separation of uranium and rare-earth elements from Rirang ore leach solution was carried out through a two-step precipitation. Several condition affecting the separation processes were examined including solution pH, reagent concentration, and reaction prepitation time. Optimum conditions for the first and second precipitation steps include adjustment of precipitation pH to 1.3 and 2.3, respectively by the addition of 7.3% of NH 4 OH solution and allowing 60 minutes precipitation/reaction time. Based on the conditions, about 6% of Th, 3% of U, 0.9% of PO 4 3- , and none of RE were recovered in the first precipitation step meanwhile, about 99% of RE, 55% of U, 76% of PO 4 3- , and of the Th were recovered in the second step. (author). 3 refs. 4 tabs. 4 figs

Multi-purpose canisters as an alternative for storage, transportation, and disposal of spent nuclear fuel

International Nuclear Information System (INIS)

Hollaway, W.R.; Rozier, R.; Nitti, D.A.; Williams, J.R.

1993-01-01

A study was conducted to assess the feasibility of using multi-purpose canisters to handle spent nuclear fuel throughout the Civilian Radioactive Waste Management System. Multi-purpose canisters would be sealed, metallic containers maintaining multiple spent fuel assemblies in a dry, inert environment and overpacked separately and uniquely for the various system elements of storage, transportation, and disposal. Using five implementation scenarios, the multi-purpose canister was evaluated with regard to several measures of effectiveness, including number of handlings, radiation exposure, cost, schedule and licensing considerations, and public perception. Advantages and disadvantages of the multi-purpose canister were identified relative to the current reference system within each scenario, and the scenarios were compared to determine the most effective method of implementation

Rapid ion-exchange separations of actinides

International Nuclear Information System (INIS)

Usuda, Shigekazu

1988-01-01

For the purpose of studying short-lived actinide nuclides, three methods for rapid ion exchange separation of actinide elements with mineral acid-alcohol mixed media were developed: anion exchange with nitric acid-methyl alcohol mixed media to separate the transplutonium and rare earth elements from target material, U or Pu and Al catcher foils; anion exchange with hydrochloric acid-methyl alcohol media to separate Am+Cm, Bk and Cf+Fm from the target, catcher foils and major fission products; and cation exchange with hydrochloric acid-methyl alcohol media and with concentrated hydrochloric acid to separate the transplutonium elements as a group from the rare earths after eliminating the large amounts of U, Al, Cu, Fe etc. The methods enable one to perform rapid and effective separation at elevated temperature (90 deg C) and immediate source preparation for alpha-ray spectrometry. (author) 47 refs.; 10 figs

Sequential separation of transuranic elements and fission products from uranium metal ingots in electrolytic reduction process of spent PWR fuels

International Nuclear Information System (INIS)

Chang Heon Lee; Kih Soo Joe; Won Ho Kim; Euo Chang Jung; Kwang Yong Jee

2009-01-01

A sequential separation procedure has been developed for the determination of transuranic elements and fission products in uranium metal ingot samples from an electrolytic reduction process for a metallization of uranium dioxide to uranium metal in a medium of LiCl-Li 2 O molten salt at 650 deg C. Pu, Np and U were separated using anion-exchange and tri-n-butylphosphate (TBP) extraction chromatography. Cs, Sr, Ba, Ce, Pr, Nd, Sm, Eu, Gd, Zr and Mo were separated in several groups from Am and Cm using TBP and di(2-ethylhexyl)phosphoric acid (HDEHP) extraction chromatography. Effect of Fe, Ni, Cr and Mg, which were corrosion products formed through the process, on the separation of the analytes was investigated in detail. The validity of the separation procedure was evaluated by measuring the recovery of the stable metals and 239 Pu, 237 Np, 241 Am and 244 Cm added to a synthetic uranium metal ingot dissolved solution. (author)

The multi-element probabilistic collocation method (ME-PCM): Error analysis and applications

International Nuclear Information System (INIS)

Foo, Jasmine; Wan Xiaoliang; Karniadakis, George Em

2008-01-01

Stochastic spectral methods are numerical techniques for approximating solutions to partial differential equations with random parameters. In this work, we present and examine the multi-element probabilistic collocation method (ME-PCM), which is a generalized form of the probabilistic collocation method. In the ME-PCM, the parametric space is discretized and a collocation/cubature grid is prescribed on each element. Both full and sparse tensor product grids based on Gauss and Clenshaw-Curtis quadrature rules are considered. We prove analytically and observe in numerical tests that as the parameter space mesh is refined, the convergence rate of the solution depends on the quadrature rule of each element only through its degree of exactness. In addition, the L 2 error of the tensor product interpolant is examined and an adaptivity algorithm is provided. Numerical examples demonstrating adaptive ME-PCM are shown, including low-regularity problems and long-time integration. We test the ME-PCM on two-dimensional Navier-Stokes examples and a stochastic diffusion problem with various random input distributions and up to 50 dimensions. While the convergence rate of ME-PCM deteriorates in 50 dimensions, the error in the mean and variance is two orders of magnitude lower than the error obtained with the Monte Carlo method using only a small number of samples (e.g., 100). The computational cost of ME-PCM is found to be favorable when compared to the cost of other methods including stochastic Galerkin, Monte Carlo and quasi-random sequence methods

Computer simulation of multi-elemental fusion reactor materials

International Nuclear Information System (INIS)

Voertler, K.

2011-01-01

Thermonuclear fusion is a sustainable energy solution, in which energy is produced using similar processes as in the sun. In this technology hydrogen isotopes are fused to gain energy and consequently to produce electricity. In a fusion reactor hydrogen isotopes are confined by magnetic fields as ionized gas, the plasma. Since the core plasma is millions of degrees hot, there are special needs for the plasma-facing materials. Moreover, in the plasma the fusion of hydrogen isotopes leads to the production of high energetic neutrons which sets demanding abilities for the structural materials of the reactor. This thesis investigates the irradiation response of materials to be used in future fusion reactors. Interactions of the plasma with the reactor wall leads to the removal of surface atoms, migration of them, and formation of co-deposited layers such as tungsten carbide. Sputtering of tungsten carbide and deuterium trapping in tungsten carbide was investigated in this thesis. As the second topic the primary interaction of the neutrons in the structural material steel was examined. As model materials for steel iron chromium and iron nickel were used. This study was performed theoretically by the means of computer simulations on the atomic level. In contrast to previous studies in the field, in which simulations were limited to pure elements, in this work more complex materials were used, i.e. they were multi-elemental including two or more atom species. The results of this thesis are in the microscale. One of the results is a catalogue of atom species, which were removed from tungsten carbide by the plasma. Another result is e.g. the atomic distributions of defects in iron chromium caused by the energetic neutrons. These microscopic results are used in data bases for multiscale modelling of fusion reactor materials, which has the aim to explain the macroscopic degradation in the materials. This thesis is therefore a relevant contribution to investigate the

Creating a Test Validated Structural Dynamic Finite Element Model of the Multi-Utility Technology Test Bed Aircraft

Science.gov (United States)

Pak, Chan-Gi; Truong, Samson S.

2014-01-01

Small modeling errors in the finite element model will eventually induce errors in the structural flexibility and mass, thus propagating into unpredictable errors in the unsteady aerodynamics and the control law design. One of the primary objectives of Multi Utility Technology Test Bed, X-56A, aircraft is the flight demonstration of active flutter suppression, and therefore in this study, the identification of the primary and secondary modes for the structural model tuning based on the flutter analysis of X-56A. The ground vibration test validated structural dynamic finite element model of the X-56A is created in this study. The structural dynamic finite element model of the X-56A is improved using a model tuning tool. In this study, two different weight configurations of the X-56A have been improved in a single optimization run.

An approach to unfold the response of a multi-element system using an artificial neural network

International Nuclear Information System (INIS)

Cordes, E.; Fehrenbacher, G.; Schuetz, R.; Sprunck, M.; Hahn, K.; Hofmann, R.; Wahl, W.

1998-01-01

An unfolding procedure is proposed which aims at obtaining spectral information of a neutron radiation field by the analysis of the response of a multi-element system consisting of converter type semiconductors. For the unfolding procedure an artificial neural network (feed forward network), trained by the back-propagation method, was used. The response functions of the single elements to neutron radiation were calculated by application of a computational model for an energy range from 10 -2 eV to 10 MeV. The training of the artificial neural network was based on the computation of responses of a six-element system for a set of 300 neutron spectra and the application of the back-propagation method. The validation was performed by the unfolding of 100 computed responses. Two unfolding examples were pointed out for the determination of the neutron spectra. The spectra resulting from the unfolding procedure agree well with the original spectra used for the response computation

Advances in laser isotope separation

International Nuclear Information System (INIS)

Herman, I.P.; Bernhardt, A.F.

1988-01-01

The physical and chemical concepts required to understand laser isotope separation are presented and discussed. The numerous successful demonstrations of separating isotopes using lasers are reviewed to 1983. Emphasis is placed on the separation of 235-U from 238-U by multi-step selective ioniation of uranium atomic vapor, and on the separation of D and H and of T from D, by pulsed infrared laser multiple-photon dissociation of fluoroform and chloroform, respectively, because they are among the most successful and important examples of laser isotope separation to date. 161 refs.; 7 figs

A 2D multi-term time and space fractional Bloch-Torrey model based on bilinear rectangular finite elements

Science.gov (United States)

Qin, Shanlin; Liu, Fawang; Turner, Ian W.

2018-03-01

The consideration of diffusion processes in magnetic resonance imaging (MRI) signal attenuation is classically described by the Bloch-Torrey equation. However, many recent works highlight the distinct deviation in MRI signal decay due to anomalous diffusion, which motivates the fractional order generalization of the Bloch-Torrey equation. In this work, we study the two-dimensional multi-term time and space fractional diffusion equation generalized from the time and space fractional Bloch-Torrey equation. By using the Galerkin finite element method with a structured mesh consisting of rectangular elements to discretize in space and the L1 approximation of the Caputo fractional derivative in time, a fully discrete numerical scheme is derived. A rigorous analysis of stability and error estimation is provided. Numerical experiments in the square and L-shaped domains are performed to give an insight into the efficiency and reliability of our method. Then the scheme is applied to solve the multi-term time and space fractional Bloch-Torrey equation, which shows that the extra time derivative terms impact the relaxation process.

Reliability modelling and analysis of a multi-state element based on a dynamic Bayesian network

Science.gov (United States)

Li, Zhiqiang; Xu, Tingxue; Gu, Junyuan; Dong, Qi; Fu, Linyu

2018-04-01

This paper presents a quantitative reliability modelling and analysis method for multi-state elements based on a combination of the Markov process and a dynamic Bayesian network (DBN), taking perfect repair, imperfect repair and condition-based maintenance (CBM) into consideration. The Markov models of elements without repair and under CBM are established, and an absorbing set is introduced to determine the reliability of the repairable element. According to the state-transition relations between the states determined by the Markov process, a DBN model is built. In addition, its parameters for series and parallel systems, namely, conditional probability tables, can be calculated by referring to the conditional degradation probabilities. Finally, the power of a control unit in a failure model is used as an example. A dynamic fault tree (DFT) is translated into a Bayesian network model, and subsequently extended to a DBN. The results show the state probabilities of an element and the system without repair, with perfect and imperfect repair, and under CBM, with an absorbing set plotted by differential equations and verified. Through referring forward, the reliability value of the control unit is determined in different kinds of modes. Finally, weak nodes are noted in the control unit.

Redox speciation of final repository relevant elements using separation methods in combination with ICP mass spectrometry

International Nuclear Information System (INIS)

Graser, Carl-Heinrich

2015-01-01

The long-term safety assessment for nuclear waste repositories requires a detailed understanding of the chemistry of actinide elements in the geosphere. The development of advanced analytical tools is required to gain detailed insights into actinide redox speciation in a given system. The mobility of radionuclides is mostly determined by the geochemical conditions which control the redox state of radionuclides. Besides the longlived radionuclides plutonium (Pu) and neptunium (Np), which are key elements in high level nuclear waste, iron (Fe) represents a main component in natural systems controlling redox related geochemical processes. Analytical techniques for determining oxidation state distribution for redox sensitive radionuclides and other metal ions often have a lack of sensitivity. The detection limits of these methods (i.e. UV/vis, TRLFS, XANES) are in general in the range of ≥ 10 -6 mol.L -1 . As a consequence ultrasensitive new analytical techniques are required. Capillary electrophoresis (CE) and ion chromatography (IC) are powerful separation methods for metal ions. In the course of this thesis different speciation method for iron, neptunium and plutonium were optimized. With the optimized setup redox speciation analysis of these elements in different samples were done. Furthermore CE hyphenated to inductively coupled plasma sector field mass spectrometry (CE - ICP - SF - MS) was used to measure the redox speciation of Pu (III, IV, V, VI), Np (IV, V, VI) and Fe (II, III) at concentrations lower than 10 -7 mol.L -1 . CE coupling and separation parameters such as sample gas pressure, make up flow rate, capillary position, auxiliary gas flow, as well as the electrolyte system were optimized to obtain the maximum sensitivity. The methodes detection limits are 10 -12 mol.L -1 for Np and Pu. The various oxidation state species of Pu and Np in different samples were separated by application of an acetate based electrolyte system. The separation of Fe (II

Multi-element analyses of earthworms for radioecology

International Nuclear Information System (INIS)

Yoshida, Satoshi; Muramatsu, Yasuyuki; Peijnenburg, W.

2004-01-01

Increasing attention on the environmental radiation protection realizes that more information is required on the transfer and accumulation of radionuclides in the biological compartments of the ecosystems. Earthworms play an important role in ecosystems, and might be a good indicator of soil contamination and its effect on the ecosystem. The elemental composition of earthworms gives useful information on background levels and possible accumulation of metals as well as related radionuclides. However, data for the elemental composition of earthworms are limited except for some specific heavy metals such as Cd, Zn, Pb and Cu. In this study, earthworms and their growth media were analyzed for 35 elements, including radionuclide related elements such as Cs, Sr, Th and U, in order to obtain the basic information on the transfer parameters of the elements. The earthworms analyzed were fed in the laboratory or collected in the environment. The concentrations and transfer factors (TFs) of the elements were determined both for laboratory and natural conditions. Relatively high TFs were observed for Na, Mg, P, K, Ca, Co, Ni, Cu, Zn, As, Se, Rb, Mo and Cd. The TFs for Al, Sc, Ti, Y, Nb and lanthanide elements were low. The TFs of Cs were different depending on the medium (soil type), indicating that bioavailability of Cs in the medium might be one of the important controlling factors of Cs concentration in earthworm. (author)

The use of cation exchange matrix separation coupled with ICP-MS to directly determine platinum group element (PGE) and other trace element emissions from passenger cars equipped with diesel particulate filters (DPF)

Energy Technology Data Exchange (ETDEWEB)

Cairns, Warren R.L.; Cozzi, Giulio [Institute for the Dynamics of Environmental Processes-CNR, Venice (Italy); De Boni, Antonella; Gabrieli, Jacopo [University of Venice, Department of Environmental Science, Venice (Italy); Asti, Massimo; Merlone Borla, Edoardo; Parussa, Flavio [Centro Ricerche Fiat, Orbassano (Italy); Moretto, Ezio [FIAT Powertrain Technologies S.p.A, Turin (Italy); Cescon, Paolo; Barbante, Carlo [University of Venice, Department of Environmental Science, Venice (Italy); Institute for the Dynamics of Environmental Processes-CNR, Venice (Italy); Boutron, Claude [Laboratoire de Glaciologie et Geophysique de l' Environnement, UMR CNRS 5183, B.P. 96, Saint Martin d' Heres Cedex (France)

2011-03-15

Inductively coupled plasma-mass spectrometry coupled with cation exchange matrix separation has been optimised for the direct determination of platinum group element (PGE) and trace element emissions from a diesel engine car. After matrix separation method detection limits of 1.6 ng g{sup -1} for Pd, 0.4 ng g{sup -1} for Rh and 4.3 ng g{sup -1} for Pt were achieved, the method was validated against the certified reference material BCR 723, urban road dust. The test vehicle was fitted with new and aged catalytic converters with and without diesel particulate filters (DPF). Samples were collected after three consecutive New European Driving Cycle (NEDC) of the particulate and ''soluble'' phases using a home-made sampler optimised for trace element analysis. Emission factors for the PGEs ranged from 0.021 ng km{sup -1} for Rh to 70.5 ng km{sup -1} for Pt; when a DPF was fitted, the emission factors for the PGEs actually used in the catalysts dropped by up to 97% (for Pt). Trace element emission factors were found to drop by a maximum of 92% for Ni to a minimum of 18% for Y when a DPF was fitted; a new DPF was also found to cause a reduction of up to 86% in the emission of particulate matter. (orig.)

Laser ablation-inductively coupled plasma-dynamic reaction cell-mass spectrometry for the multi-element analysis of polymers

International Nuclear Information System (INIS)

Resano, M.; Garcia-Ruiz, E.; Vanhaecke, F.

2005-01-01

In this work, the potential of laser ablation-inductively coupled plasma-mass spectrometry for the fast analysis of polymers has been explored. Different real-life samples (polyethylene shopping bags, an acrylonitrile butadiene styrene material and various plastic bricks) as well as several reference materials (VDA 001 to 004, Cd in polyethylene) have been selected for the study. Two polyethylene reference materials (ERM-EC 680 and 681), for which a reference or indicative value for the most relevant metals is available, have proved their suitability as standards for calibration. Special attention has been paid to the difficulties expected for the determination of Cr at the μg g -1 level in this kind of materials, due to the interference of ArC + ions on the most abundant isotopes of Cr. The use of ammonia as a reaction gas in a dynamic reaction cell is shown to alleviate this problem, resulting in a limit of detection of 0.15 μg g -1 for this element, while limiting only modestly the possibilities of the technique for simultaneous multi-element analysis. In this regard, As is the analyte most seriously affected by the use of ammonia, and its determination has to be carried out in vented mode, at the expense of measuring time. In all cases studied, accurate results could be obtained for elements ranging in content from the sub-μg g -1 level to tens of thousands of μg g -1 . However, the use of an element of known concentration as internal standard may be needed for materials with a matrix significantly different from that of the standard (polyethylene in this work). Precision ranged between 5% and 10% RSD for elements found at the 10 μg g -1 level or higher, while this value could deteriorate to 20% for analytes found at the sub-μg g -1 level. Overall, the technique evaluated presents many advantages for the fast and accurate multi-element analysis of these materials, avoiding laborious digestion procedures and minimizing the risk of analyte losses due to the

Laser ablation inductively coupled plasma dynamic reaction cell mass spectrometry for the multi-element analysis of polymers

Science.gov (United States)

Resano, M.; García-Ruiz, E.; Vanhaecke, F.

2005-11-01

In this work, the potential of laser ablation-inductively coupled plasma-mass spectrometry for the fast analysis of polymers has been explored. Different real-life samples (polyethylene shopping bags, an acrylonitrile butadiene styrene material and various plastic bricks) as well as several reference materials (VDA 001 to 004, Cd in polyethylene) have been selected for the study. Two polyethylene reference materials (ERM-EC 680 and 681), for which a reference or indicative value for the most relevant metals is available, have proved their suitability as standards for calibration. Special attention has been paid to the difficulties expected for the determination of Cr at the μg g - 1 level in this kind of materials, due to the interference of ArC + ions on the most abundant isotopes of Cr. The use of ammonia as a reaction gas in a dynamic reaction cell is shown to alleviate this problem, resulting in a limit of detection of 0.15 μg g - 1 for this element, while limiting only modestly the possibilities of the technique for simultaneous multi-element analysis. In this regard, As is the analyte most seriously affected by the use of ammonia, and its determination has to be carried out in vented mode, at the expense of measuring time. In all cases studied, accurate results could be obtained for elements ranging in content from the sub-μg g - 1 level to tens of thousands of μg g - 1 . However, the use of an element of known concentration as internal standard may be needed for materials with a matrix significantly different from that of the standard (polyethylene in this work). Precision ranged between 5% and 10% RSD for elements found at the 10 μg g - 1 level or higher, while this value could deteriorate to 20% for analytes found at the sub-μg g - 1 level. Overall, the technique evaluated presents many advantages for the fast and accurate multi-element analysis of these materials, avoiding laborious digestion procedures and minimizing the risk of analyte losses due

Obtaining Approximate Values of Exterior Orientation Elements of Multi-Intersection Images Using Particle Swarm Optimization

Science.gov (United States)

Li, X.; Li, S. W.

2012-07-01

In this paper, an efficient global optimization algorithm in the field of artificial intelligence, named Particle Swarm Optimization (PSO), is introduced into close range photogrammetric data processing. PSO can be applied to obtain the approximate values of exterior orientation elements under the condition that multi-intersection photography and a small portable plane control frame are used. PSO, put forward by an American social psychologist J. Kennedy and an electrical engineer R.C. Eberhart, is a stochastic global optimization method based on swarm intelligence, which was inspired by social behavior of bird flocking or fish schooling. The strategy of obtaining the approximate values of exterior orientation elements using PSO is as follows: in terms of image coordinate observed values and space coordinates of few control points, the equations of calculating the image coordinate residual errors can be given. The sum of absolute value of each image coordinate is minimized to be the objective function. The difference between image coordinate observed value and the image coordinate computed through collinear condition equation is defined as the image coordinate residual error. Firstly a gross area of exterior orientation elements is given, and then the adjustment of other parameters is made to get the particles fly in the gross area. After iterative computation for certain times, the satisfied approximate values of exterior orientation elements are obtained. By doing so, the procedures like positioning and measuring space control points in close range photogrammetry can be avoided. Obviously, this method can improve the surveying efficiency greatly and at the same time can decrease the surveying cost. And during such a process, only one small portable control frame with a couple of control points is employed, and there are no strict requirements for the space distribution of control points. In order to verify the effectiveness of this algorithm, two experiments are

OBTAINING APPROXIMATE VALUES OF EXTERIOR ORIENTATION ELEMENTS OF MULTI-INTERSECTION IMAGES USING PARTICLE SWARM OPTIMIZATION

Directory of Open Access Journals (Sweden)

X. Li

2012-07-01

Full Text Available In this paper, an efficient global optimization algorithm in the field of artificial intelligence, named Particle Swarm Optimization (PSO, is introduced into close range photogrammetric data processing. PSO can be applied to obtain the approximate values of exterior orientation elements under the condition that multi-intersection photography and a small portable plane control frame are used. PSO, put forward by an American social psychologist J. Kennedy and an electrical engineer R.C. Eberhart, is a stochastic global optimization method based on swarm intelligence, which was inspired by social behavior of bird flocking or fish schooling. The strategy of obtaining the approximate values of exterior orientation elements using PSO is as follows: in terms of image coordinate observed values and space coordinates of few control points, the equations of calculating the image coordinate residual errors can be given. The sum of absolute value of each image coordinate is minimized to be the objective function. The difference between image coordinate observed value and the image coordinate computed through collinear condition equation is defined as the image coordinate residual error. Firstly a gross area of exterior orientation elements is given, and then the adjustment of other parameters is made to get the particles fly in the gross area. After iterative computation for certain times, the satisfied approximate values of exterior orientation elements are obtained. By doing so, the procedures like positioning and measuring space control points in close range photogrammetry can be avoided. Obviously, this method can improve the surveying efficiency greatly and at the same time can decrease the surveying cost. And during such a process, only one small portable control frame with a couple of control points is employed, and there are no strict requirements for the space distribution of control points. In order to verify the effectiveness of this algorithm

Interactive Approach for Multi-Level Multi-Objective Fractional Programming Problems with Fuzzy Parameters

Directory of Open Access Journals (Sweden)

M.S. Osman

2018-03-01

Full Text Available In this paper, an interactive approach for solving multi-level multi-objective fractional programming (ML-MOFP problems with fuzzy parameters is presented. The proposed interactive approach makes an extended work of Shi and Xia (1997. In the first phase, the numerical crisp model of the ML-MOFP problem has been developed at a confidence level without changing the fuzzy gist of the problem. Then, the linear model for the ML-MOFP problem is formulated. In the second phase, the interactive approach simplifies the linear multi-level multi-objective model by converting it into separate multi-objective programming problems. Also, each separate multi-objective programming problem of the linear model is solved by the ∊-constraint method and the concept of satisfactoriness. Finally, illustrative examples and comparisons with the previous approaches are utilized to evince the feasibility of the proposed approach.

Neutron activation analysis of trace elements in foodstuffs

International Nuclear Information System (INIS)

Schelenz, R.; Bayat, I.; Fischer, E.

1976-05-01

For the determination of trace elements in foodstuffs with the aid of neutron activation analysis the separation of volatile radionuclides after digestion of the sample is of special interest for radiochemical processing. A distillation procedure was developed to give reproducable results, however optimal conditions were not found for all volatile radionuclides studied. The required selective separation of Br-82 from the distillate was best achieved by the application of an ion-exchange column-chromatography technique. The computer programs for the evaluation of complex gamma spectra have been developed further. The automatic peak search and peak area determination is based on a computer program using the correlation technique and carried out with a mini-computer coupled with a multi-channel gamma spectrometer. The results, which are presented in 3 earlier reports relating to this research program, reveal the advantages and disadvantages of the individual steps of the radiochemical separation scheme. Before neutron activation analysis can be introduced on a routine basis, some aspects of the radiochemical process remain to be tested; these studies will be published in a fourth and final report. (orig.) [de

High atomic weight isotope separator

International Nuclear Information System (INIS)

Book, D.L.

1978-01-01

A continuously operating device is described which separates one isotopic species of a given element from a mixture. The given element is vaporized and formed into a neutral beam containing the isotopes desired to be separated. The plasma is accelerated through a laser beam which is formed by two separate lasers which operate in the continuous wave mode in which the beams are as nearly as possible in the same beam path. The two laser output beams excite and ionize the isotope of interest while leaving the remaining atoms unaffected. The ionized isotopes are then separated from the beam by an electrostatic deflection technique and the unaffected atoms continue on in their path and are directed to a recovery device

Development and validation of a numerical model for cross-section optimization of a multi-part probe for soft tissue intervention.

Science.gov (United States)

Frasson, L; Neubert, J; Reina, S; Oldfield, M; Davies, B L; Rodriguez Y Baena, F

2010-01-01

The popularity of minimally invasive surgical procedures is driving the development of novel, safer and more accurate surgical tools. In this context a multi-part probe for soft tissue surgery is being developed in the Mechatronics in Medicine Laboratory at Imperial College, London. This study reports an optimization procedure using finite element methods, for the identification of an interlock geometry able to limit the separation of the segments composing the multi-part probe. An optimal geometry was obtained and the corresponding three-dimensional finite element model validated experimentally. Simulation results are shown to be consistent with the physical experiments. The outcome of this study is an important step in the provision of a novel miniature steerable probe for surgery.

Separation of some hazardous elements by natural materials

International Nuclear Information System (INIS)

Metwally, E.; Shehata, M.K.K.; Sharaf El Deen, S.E.A.

2000-01-01

A study has been conducted to study the uptake of radio europium and radiocesium as representatives of fission products in addition to the element chromium as a heavy metal ion, straw and sugarcane residue as representatives of natural cheap materials. Radiometric measurements and spectrophotometric analysis of concerned elements were the techniques adopted in this work. Factors affecting the uptake behavior of the studied elements on different types of straw (Rice, wheat and maize) in addition to sugarcane residue were studied. Such factors are the Ph, contact time, ion concentration and type of media. The uptake % of Cr(III) on straw and sugarcane samples is found to reach 100% at Ph=1, while that of Cr(Vi) does not exceed 15% on the same samples at higher Ph values. While uptake % of Eu(III) reaches 75% with all studied materials. The uptake % of Cs(I) on straw and sugarcane samples is found to be 80% in a short time then decreases sharply

Radiation gradient isotope separator

International Nuclear Information System (INIS)

Hughes, J.L.

1980-01-01

A system is described for transporting, separating and storing charged particles, charged antiparticles and fully or partially ionized isotopes of any element comprising a laser beam generator, laser beam intensity profiler, a laser beam variable intensity attenuator, and means for injecting charged particles, charged antiparticles and ionized isotopes into the beam and extracting them from the system as required. The invention is particularly useful for channelling electrons and ions used for fuel pellet compression in inertial fusion systems, for separating the isotopes of elements and for the confinement of charged antiparticles and particle/antiparticle plasmas

Separation of non-stationary multi-source sound field based on the interpolated time-domain equivalent source method

Science.gov (United States)

Bi, Chuan-Xing; Geng, Lin; Zhang, Xiao-Zheng

2016-05-01

In the sound field with multiple non-stationary sources, the measured pressure is the sum of the pressures generated by all sources, and thus cannot be used directly for studying the vibration and sound radiation characteristics of every source alone. This paper proposes a separation model based on the interpolated time-domain equivalent source method (ITDESM) to separate the pressure field belonging to every source from the non-stationary multi-source sound field. In the proposed method, ITDESM is first extended to establish the relationship between the mixed time-dependent pressure and all the equivalent sources distributed on every source with known location and geometry information, and all the equivalent source strengths at each time step are solved by an iterative solving process; then, the corresponding equivalent source strengths of one interested source are used to calculate the pressure field generated by that source alone. Numerical simulation of two baffled circular pistons demonstrates that the proposed method can be effective in separating the non-stationary pressure generated by every source alone in both time and space domains. An experiment with two speakers in a semi-anechoic chamber further evidences the effectiveness of the proposed method.

Multi-element analysis of small biological samples

International Nuclear Information System (INIS)

Rokita, E.; Cafmeyer, J.; Maenhaut, W.

1983-01-01

A method combining PIXE and INAA was developed to determine the elemental composition of small biological samples. The method needs virtually no sample preparation and less than 1 mg is sufficient for the analysis. The method was used for determining up to 18 elements in leaves taken from Cracow Herbaceous. The factors which influence the elemental composition of leaves and the possible use of leaves as an environmental pollution indicator are discussed

Multi-elemental characterization of Cuban natural zeolites

International Nuclear Information System (INIS)

Rizo, O.D.; Peraza, E.F.H.

1997-01-01

Concentration of 38 elements in samples from four important Cuban zeolite beds have been obtained by Instrumental Neutron Activation (INAA) and X-ray Fluorescence analyses (XRFA). In comparison with other analytical techniques good agreement was reached. The concentration values of minor element Ba, Sr, Zn and Mn and 25 trace element (including 9 REE) are at the first time reported in Cuban zeolite. It is important for the zeolite evaluation in different industrial uses. (author)

Multi-elemental characterization of Cuban natural zeolites

International Nuclear Information System (INIS)

Diaz Rizo, O.; Herrera Peraza, E.F.

1996-01-01

Concentrations of 38 elements in samples from four important Cuban zeolite bed have beam obtained by Instrumental Neutron Activation (INAA) and X-Ray Fluorescence Analysis (XRFA). In comparison with other analytical techniques good agreement was achieved. The concentration values of minor element Ba, Sr, Zn, and Mn, and 25 trace element (including 9 REE) are at the first time reported in Cuban zeolite. It is important for the zeolite evaluation in different industrial uses

Anomalous decrease in X-ray diffraction intensities of Cu-Ni-Al-Co-Cr-Fe-Si alloy systems with multi-principal elements

International Nuclear Information System (INIS)

Yeh, J.-W.; Chang, S.-Y.; Hong, Y.-D.; Chen, S.-K.; Lin, S.-J.

2007-01-01

With an aim to understand the great reduction in the X-ray diffraction (XRD) intensities of high-entropy alloys, a series of Cu-Ni-Al-Co-Cr-Fe-Si alloys with systematic addition of principal elements from pure element to seven elements was investigated for quantitative analysis of XRD intensities. The variation of XRD peak intensities of the alloy system is similar to that caused by thermal effect, but the intensities further drop beyond the thermal effect with increasing number of incorporated principal elements. An intrinsic lattice distortion effect caused by the addition of multi-principal elements with different atomic sizes is expected for the anomalous decrease in XRD intensities. The mathematical factor of this distortion effect for the modification of XRD structure factor is formulated analogue to that of thermal effect

Extraction separation of americium and curium. A review

International Nuclear Information System (INIS)

Petrzilova, H.

1976-11-01

A survey is given of extraction systems suitable for transplutonium element separation and preparation as well as for the practical application of their nuclear properties. Methods are discussed in detail of separating the actinide and the lanthanide fractions from fission and corrosion products and of separating americium from curium. The description is completed with flowsheets showing the separation of transplutonium elements from irradiated targets and waste solutions after spent fuel reprocessing. (L.K.)

Group separation of rare earth elements by liquid-liquid extraction for the neutron activation analysis of silicate rocks

International Nuclear Information System (INIS)

Wyttenbach, A.; Bajo, S.; Tobler, L.

1983-01-01

Rare earth elements are isolated as a group from neutron activated rock samples by a new radiochemical procedure based on extraction with thenoyltrifluoracetone/phenanthroline in CHCl 3 . The procedure consists of three extraction steps, obviates the use of inactive carriers and gives practically quantitative chemical yields, thereby avoiding fractionation of the individual rare earths. Details of the dissolution, chemical separations. and counting procedure are given together with an analysis of BCR-1. (author)

Separation of short-lived fission products

International Nuclear Information System (INIS)

Tamai, Tadaharu; Ohyoshi, Emiko; Ohyoshi, Akira; Kiso, Yoshiyuki; Shinagawa, Mutsuaki.

1976-01-01

A rbief review is presented on the various methods of separation available for both gaseous and liquid states, for the separation of short-lived fission products formed by binary fission of neutron irradiated uranium. The means available for gaseous state are the hot atom reaction, the hydride method and on-line mass separation. For liquid state, use can be made of precipitation, ionic or atomic exchange, solvent extraction and paper electrophoresis. Particular reference is made to electrophoretic separation of ions produced by fission in aqueous solution of uranium. The principle of electrophoretic separation and the procedures for separating the element of interest from the other fission products are outlined, with reference made to the results obtained with the method by the present authors. The elements in question are alkalines, alkaline earths, rare earths, halogens, selenium and

An adaptive multi-element probabilistic collocation method for statistical EMC/EMI characterization

KAUST Repository

Yücel, Abdulkadir C.

2013-12-01

An adaptive multi-element probabilistic collocation (ME-PC) method for quantifying uncertainties in electromagnetic compatibility and interference phenomena involving electrically large, multi-scale, and complex platforms is presented. The method permits the efficient and accurate statistical characterization of observables (i.e., quantities of interest such as coupled voltages) that potentially vary rapidly and/or are discontinuous in the random variables (i.e., parameters that characterize uncertainty in a system\\'s geometry, configuration, or excitation). The method achieves its efficiency and accuracy by recursively and adaptively dividing the domain of the random variables into subdomains using as a guide the decay rate of relative error in a polynomial chaos expansion of the observables. While constructing local polynomial expansions on each subdomain, a fast integral-equation-based deterministic field-cable-circuit simulator is used to compute the observable values at the collocation/integration points determined by the adaptive ME-PC scheme. The adaptive ME-PC scheme requires far fewer (computationally costly) deterministic simulations than traditional polynomial chaos collocation and Monte Carlo methods for computing averages, standard deviations, and probability density functions of rapidly varying observables. The efficiency and accuracy of the method are demonstrated via its applications to the statistical characterization of voltages in shielded/unshielded microwave amplifiers and magnetic fields induced on car tire pressure sensors. © 2013 IEEE.

Effects of Heat Input and Bead Generation Methods on Finite Element Analysis of Multi-Pass Welding Process

Energy Technology Data Exchange (ETDEWEB)

Park, Won Dong; Kim, Ji Hoon; Bahn, Chi Bum [Pusan National University, Busan (Korea, Republic of)

2016-10-15

Welding residual stresses are determined by various factors such as heat input, initial temperature of molten bead, heating time, cooling time, cooling conditions, and boundary conditions. In this study, a sensitivity analysis was performed to find the major factors and reasonable assumptions for simulation. Two-dimensional axisymmetric simulation was conducted by using commercial finite element analysis program ABAQUS, for multi-pass Alloy 82 welds in a 304 Stainless Steel and SA-105 Carbon Steel. The major object is to evaluate effects of the heat input methods and weld bead generation methods on the welding residual stress distribution. Totally four kinds of methods were compared. From the previous results, we could make the following conclusions. 1. Although there are non-negligible differences in HAZ depending on heat input method, welding residual stress distributions have roughly similar trends. However, it is needed to perform the more exact analysis to apply heat energy more carefully into the individual bead. 2. Residual stress distribution were similar for the two weld bead generation technique. However, overlapping was happened when element birth technique was applied. Effects of overlapping could not ignore as deformation increases. However, overlapping problem was avoided when quiet element technique was used. 3. Since existence of inactive bead elements, inaccurate weld residual stresses could be occurred in boundaries of previous and next weld elements in case of quiet element technique.

Multi-element determination of soil solution by INAA

International Nuclear Information System (INIS)

Qian Qinfang; Wu Shuiqing; Tian Jibing

1992-01-01

One of the factors influencing crop growth is the effective elemental contents, especially trace elements, under the circumstances of the same concentrations of N, P and K in soil. In order to obtain the data of effective elemental contents in soil, a novel method was introduced. In this method, soil solution was extracted by a squeezer. The concentrations of elements in soil solution were determined by INAA. Study on the compositions and the contents of elements in soil solution will provide information on making a suitable soil environment for plant growth and on rational and economical manuring

A Single Rod Multi-modality Multi-interface Level Sensor Using an AC Current Source

Directory of Open Access Journals (Sweden)

Abdulgader Hwili

2008-05-01

Full Text Available Crude oil separation is an important process in the oil industry. To make efficient use of the separators, it is important to know their internal behaviour, and to measure the levels of multi-interfaces between different materials, such as gas-foam, foam-oil, oil-emulsion, emulsion-water and water-solids. A single-rod multi-modality multi-interface level sensor is presented, which has a current source, and electromagnetic modalities. Some key issues have been addressed, including the effect of salt content and temperature i.e. conductivity on the measurement.

Isotope separation process

International Nuclear Information System (INIS)

Kaldor, A.; Rabinowitz, P.

1979-01-01

A method of separating the isotopes of an element is described, which comprises the steps of (i) subjecting molecules of a gaseous compound of the element simultaneously to two infrared radiations of different wavelengths, the first radiation having a wavelength which corresponds to an absorption band of the compound, which in turn corresponds to a mode of molecular motion in which there is participation by atoms of the element, and the second radiation having a power density greater than 10 6 watts per cm 2 , thereby exciting molecules of the compound in an isotopically selective manner, this step being conducted in such manner that the excited molecules either receive a level of energy sufficient to cause them to undergo conversion by unimolecular decomposition or receive a level of energy sufficient to cause them to undergo conversion by reaction with molecules of another gas present for that purpose; and (ii) separating and recovering converted molecules from unconverted molecules. (author)

The RIKEN gas-filled recoil separator and a possible new approach to superheavy elements by the (HI, αxn) reaction

International Nuclear Information System (INIS)

Nomura, T.

1990-10-01

The (HI, αxn) reaction, in which precompound α particle emission takes place, is shown to occur significantly even near the Coulomb barrier. Because the α emission can efficiently cool down a highly excited nucleus both in energy and angular momentum, it is considered to be very effective for production of heavy elements like SHE. However, the angular distributions of residual nuclei produced in this reaction are side-peaked, requiring a recoil-type separator with large angular acceptance when it is applied for collection of the relevant nuclei. A brief description is given about a gas-filled separator recently constructed at RIKEN, which meets the above requirement. (author)

SEPARATION OF TRANSURANIC ELEMENTS FROM RARE EARTH COMPOUNDS

Science.gov (United States)

Kohman, T.P.

1961-11-21

A process of separating neptunium and plutonium values from rare earths and alkaline earth fission products present on a solid mixed actinide carrier (Th or U(IV) oxalate or fluoride) --fission product carrier (LaF/sub 3/, CeF/sub 3/, SrF/sub 2/, CaF/sub 2/, YF/sub 3/, La oxalate, cerous oxalate, Sr oxalate, Ca oxalate or Y oxalate) by extraction of the actinides at elevated temperature with a solution of ammonium fluoride and/or ammonium oxalate is described. Separation of the fission-product-containing carriers from the actinide solution formed and precipitation of the neptunium and plutonium from the solution with mineral acid are also accomplished. (AEC)

Electrothermal vaporisation ICP-mass spectrometry (ETV-ICP-MS) for the determination and speciation of trace elements in solid samples - A review of real-life applications from the author's lab

Energy Technology Data Exchange (ETDEWEB)

Vanhaecke, Frank; Resano, Martin; Moens, Luc [Laboratory of Analytical Chemistry, Ghent University, Institute for Nuclear Sciences, Proeftuinstraat 86, 9000 Ghent (Belgium)

2002-09-01

The use of electrothermal vaporisation (ETV) from a graphite furnace as a means of sample introduction in inductively coupled plasma mass spectrometry (ICP-MS) permits the direct analysis of solid samples. A multi-step furnace temperature programme is used to separate the vaporisation of the target element(s) and of the matrix components from one another. Sometimes, a chemical modifier is used to enable a higher thermal pre-treatment temperature, by avoiding premature analyte losses (stabilisation) or promoting the selective volatilisation of matrix components. In almost all instances, accurate results can be obtained via external calibration or single standard addition using an aqueous standard solution. Absolute limits of detection are typically 1 pg, which corresponds to 1 ng/g for a typical sample mass of 1 mg. Real-life applications carried out in the author's lab are used to illustrate the utility of this approach. These applications aim at trace element determination in industrial and environmental materials. The industrial materials analysed include different types of plastics - Carilon, polyethylene, poly(ethyleneterephtalate) and polyamide - and photo- and thermographic materials. As samples from environmental origin, plant material, animal tissue and sediments were investigated. Some applications aimed at a multi-element determination, while in other, the content of a single, but often challenging, element (e.g., Si or S) had to be measured. ETV-ICP-MS was also used in elemental speciation studies. Separation of Se-containing proteins was accomplished using polyacrylamide gel electrophoresis (PAGE). Subsequent quantification of the Se content in the protein spots was carried out using ETV-ICP-MS. As the volatilisation of methylmercury and inorganic mercury could be separated from one another with respect to time, no chromatographic or electrophoretic separation procedure was required, but ETV-ICP-MS as such sufficed for Hg speciation in fish tissue

Blind speech separation system for humanoid robot with FastICA for audio filtering and separation

Science.gov (United States)

Budiharto, Widodo; Santoso Gunawan, Alexander Agung

2016-07-01

Nowadays, there are many developments in building intelligent humanoid robot, mainly in order to handle voice and image. In this research, we propose blind speech separation system using FastICA for audio filtering and separation that can be used in education or entertainment. Our main problem is to separate the multi speech sources and also to filter irrelevant noises. After speech separation step, the results will be integrated with our previous speech and face recognition system which is based on Bioloid GP robot and Raspberry Pi 2 as controller. The experimental results show the accuracy of our blind speech separation system is about 88% in command and query recognition cases.

Separations chemistry

International Nuclear Information System (INIS)

Anon.

1976-01-01

Results of studies on the photochemistry of aqueous Pu solutions and the stability of iodine in liquid and gaseous CO 2 are reported. Progress is reported in studies on: the preparation of macroporous bodies filled with oxides and sulfides to be used as adsorbents; the beneficiation of photographic wastes; the anion exchange adsorption of transition elements from thiosulfate solutions; advanced filtration applications of energy significance; high-resolution separations; and, the examination of the separation agents, octylphenylphosphoric acid (OPPA) and trihexyl phosphate (THP)

Superheavy element chemistry. Achievements and perspectives

International Nuclear Information System (INIS)

Schaedel, M.

2007-01-01

Superheavy elements have been synthesized and chemically characterized one-atom-at-a-time up to element 108. Presently, the quest for element 112 is one of the hottest topics in this field. The transactinide elements 104 to 108 are members of group 4 to 8 of the Periodic Table and element 112 belongs into group 12. Chemical properties of some of these elements, like elements 104 and 105, show stunning deviations from simple extrapolations within their respective group while others exhibit great similarities with their lighter homologues elements. First experiments to investigate seaborgium (Sg, element 106) in aqueous solution were performed. Again, in large international collaborations at the GSI, several gas-phase chemistry experiments were performed with hassium (Hs, element 108). Recently, the highly efficient and very clean separation of Hs was applied for nuclear studies of various Hs nuclides investigating their cross section and their nuclear decay properties in the region of the doubly-magic 270 Hs (Z=108, N=162). To overcome certain limitations of the presently used on-line chemical separations the new TransActinide Separation and Chemistry Apparatus (TASCA) - with a gas-filled recoil separator as a front-end tool - was designed and built at the GSI in a collaborative effort. Presently in its commissioning phase, TASCA shall be a key instrument for a big leap into quantitatively and qualitatively new experiments in the region of superheavy elements. (author)

Chromatographic hydrogen isotope separation

International Nuclear Information System (INIS)

Aldridge, F.T.

1983-01-01

Intermetallic compounds with the CaCu5 type of crystal structure, particularly LaNiCo and CaNi5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation column. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale multi-stage chromatographic separation process run as a secondary process off a hydrogen feedstream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors

First superheavy element experiments at the GSI recoil separator TASCA: The production and decay of element 114 in the 244Pu(48Ca,3-4n) reaction

International Nuclear Information System (INIS)

Gates, J. M.; Duellmann, Ch. E.; Schaedel, M.; Ackermann, D.; Block, M.; Bruechle, W.; Essel, H. G.; Hartmann, W.; Hessberger, F. P.; Huebner, A.; Jaeger, E.; Khuyagbaatar, J.; Kindler, B.; Krier, J.; Kurz, N.; Lommel, B.; Schaffner, H.; Schausten, B.; Schimpf, E.; Steiner, J.

2011-01-01

Experiments with the new recoil separator, Transactinide Separator and Chemistry Apparatus (TASCA), at the GSI were performed by using beams of 48 Ca to irradiate targets of 206-208 Pb, which led to the production of 252-254 No isotopes. These studies allowed for evaluation of the performance of TASCA when coupled to a new detector and electronics system. By following these studies, the isotopes of element 114 ( 288-291 114) were produced in irradiations of 244 Pu targets with 48 Ca beams at compound nucleus excitation energies around 41.7 and 37.5 MeV, demonstrating TASCA's ability to perform experiments with picobarn-level cross sections. A total of 15 decay chains were observed and were assigned to the decay of 288-291 114. A new α-decay branch in 281 Ds was observed, leading to the new nucleus 277 Hs.

Study on Yen Phu rare earth ore concentrate treatment technology and separation of major heavy rare earth elements by solvent extraction method

International Nuclear Information System (INIS)

Le Ba Thuan; Pham Quang Trung; Vu Lap Lai

2003-01-01

1. Yenphu rare earth ore concentrate treatment by alkali under pressure: On the base of studying mineral and chemical compositions of Yenphu rare earth ore concentrate containing 28% TREO and conditions for digestion of ore concentrate by alkali under pressure such as ore concentrate/ NaOH ratio, alkali concentration, pressure and temperature at bench scale (100 gram and 5 kg per batch), the optimal conditions for decomposition of REE ore concentrate have been determined. The yield of the decomposition stage is about 90%. The studies on alkali washing, REE leaching by HCl, pH for leaching process, and iron and radioactive impurities removing by Na 2 S + Na 2 PO 4 have been carried out. The obtained results show that mixture of Na 2 S 5% + Na2PO 4 1% is effective in iron and radioactive impurities removing. The obtained REE oxides get purity of > 99% and meet the need of solvent extraction (SX) individual separation of rare earth elements. The schema for recovery of REEs from Yenphu REE ore concentrate by alkali decomposition under high pressure has been proposed. 2. Fractionation of Yenphu rare earth mixture into subgroups by solvent extraction with PC88A: On the base of simulation program, the parameters for fractional process of rare earths mixture into subgroups by solvent extraction with PC88A have been proposed and determined by experimental verification on mixer-settler set. According to this process, rare earths mixture fractionated into yttrium and light subgroups. In their turn, the light subgroup was separated into light (La, Ce, Pr, Nd) and middle (Sm, Eu, Gd) subgroups. The average yield of the process reached value > 95%. The composition of light subgroup meets the needs for individual separation of Gd, Eu, and Sm. 3. Separation and purification of yttrium: The process for recovery of yttrium consists of two stages: upgrade to get high quality Y concentrate by PC88A and purification by Aliquat 336 in NH 4 SCN-NH 4 Cl medium. The process parameter for

Influence of throttling of the heavy fraction on the uranium isotope separation in the separation nozzle

International Nuclear Information System (INIS)

Bley, P.; Ehrfeld, W.; Heiden, U.

1978-04-01

In a separation nozzle cascade for enrichment of U-235 the cut of the separation elements is adjusted by throttling the heavy fraction. This control process influences directly the flow properties in the nozzle and may noticeably change its separation characteristics. This paper deals with an experimental investigation of the throttling effect on the separation and control characteristics of the separation nozzle operated with a H 2 /UF 6 mixture. In consideration of the extremely small characteristic dimensions of commercial separation nozzle elements the influence of manufacturing tolerances on the characteristics of the throttled nozzle was analysed in detail. It appears, that the elementary effect of isotope separation increases by throttling of the heavy fraction up to 5% without changing the optimum operating conditions. This increase of the elementary effect is not only obtained for separation nozzles with zero tolerances but also for separation nozzles having finite tolerances of the skimmer position. Tolerances of the nozzle width, however, become increasingly detrimental, when the heavy fraction is throttled. Regarding the control characteristics of the separation nozzle it was found out, that the UF 6 -cut of the throttled nozzle reacts more sensitively to alterations of the operating pressures and less sensitively to alterations of the UF 6 -concentration of the process gas mixture. (orig.) [de

Detailed Modeling and Irreversible Transfer Process Analysis of a Multi-Element Thermoelectric Generator System

Science.gov (United States)

Xiao, Heng; Gou, Xiaolong; Yang, Suwen

2011-05-01

Thermoelectric (TE) power generation technology, due to its several advantages, is becoming a noteworthy research direction. Many researchers conduct their performance analysis and optimization of TE devices and related applications based on the generalized thermoelectric energy balance equations. These generalized TE equations involve the internal irreversibility of Joule heating inside the thermoelectric device and heat leakage through the thermoelectric couple leg. However, it is assumed that the thermoelectric generator (TEG) is thermally isolated from the surroundings except for the heat flows at the cold and hot junctions. Since the thermoelectric generator is a multi-element device in practice, being composed of many fundamental TE couple legs, the effect of heat transfer between the TE couple leg and the ambient environment is not negligible. In this paper, based on basic theories of thermoelectric power generation and thermal science, detailed modeling of a thermoelectric generator taking account of the phenomenon of energy loss from the TE couple leg is reported. The revised generalized thermoelectric energy balance equations considering the effect of heat transfer between the TE couple leg and the ambient environment have been derived. Furthermore, characteristics of a multi-element thermoelectric generator with irreversibility have been investigated on the basis of the new derived TE equations. In the present investigation, second-law-based thermodynamic analysis (exergy analysis) has been applied to the irreversible heat transfer process in particular. It is found that the existence of the irreversible heat convection process causes a large loss of heat exergy in the TEG system, and using thermoelectric generators for low-grade waste heat recovery has promising potential. The results of irreversibility analysis, especially irreversible effects on generator system performance, based on the system model established in detail have guiding significance for

Optimization and Openmp Parallelization of a Discrete Element Code for Convex Polyhedra on Multi-Core Machines

Science.gov (United States)

Chen, Jian; Matuttis, Hans-Georg

2013-02-01

We report our experiences with the optimization and parallelization of a discrete element code for convex polyhedra on multi-core machines and introduce a novel variant of the sort-and-sweep neighborhood algorithm. While in theory the whole code in itself parallelizes ideally, in practice the results on different architectures with different compilers and performance measurement tools depend very much on the particle number and optimization of the code. After difficulties with the interpretation of the data for speedup and efficiency are overcome, respectable parallelization speedups could be obtained.

Multi element analysis by X-ray fluorescence. A powerful tool of ivory identification from various origins

International Nuclear Information System (INIS)

Kautenburger, R.; Mueller, P.; Wannemacher, J.

2004-01-01

The 11th CITES Conference in 2000 decided to maintain a total worldwide ban on trade of elephant ivory. The 12th Conference in 2002 decided to allow a conditional trade in stockpiled ivory in 2004. Reopening of the ivory trade would require methods to identify the origin of the ivory so that legal ivory can be distinguished from the black-market ones. X-ray fluorescence multi-element analysis of ivory samples from various regions of Africa and Southeast-Asia to characterize ivory of the various elephant populations is described. (author)

Electromigration in molten salts and application to isotopic separation of alkaline and alkaline-earth elements

International Nuclear Information System (INIS)

Menes, F.

1969-01-01

The separation of the isotopes of the alkaline-earth elements has been studied using counter-current electromigration in molten bromides. The conditions under which the cathode operates as a bromine electrode for the highest possible currents have been examined. For the separation of calcium, it has been necessary to use a stable CaBr 2 - (CaBr 2 + KBr) 'chain'. In the case of barium and strontium, it was possible to employ the pure bromides. Enrichment factors of the order of 10 for 48 Ca and of the order of 1.5 for the rare isotopes of barium and strontium have been obtained. In the case of magnesium the method is slightly more difficult to apply because of material loss due to the relatively high vapour pressure of the salt requiring the use of electrolyte chains, MgBr 2 - CeBr 3 . A study has been made that has led to a larger-scale application of the method. These are essentially the inhibition of reversible operation of the cathode by traces of water, limiting the intensity which can be tolerated; evacuation of the heat produced by the Joule effect, in the absence of which the separation efficiency is reduced by thermal gradients; corrosion of the materials by molten salts at high temperature. Several cells capable of treating a few kilograms of substance have been put into operation; none of these has lasted long enough to produce a satisfactory enrichment. The method is thus limited actually to yields of the order of a few grams. (author) [fr

Evolutionary algorithm-based multi-criteria optimization of triboelectrostatic separator

Czech Academy of Sciences Publication Activity Database

Mach, F.; Adam, L.; Kacerovský, J.; Karban, P.; Doležel, Ivo

2014-01-01

Roč. 270, November (2014), s. 134-142 ISSN 0377-0427 R&D Projects: GA ČR(CZ) GAP102/11/0498 Institutional support: RVO:61388998 Keywords : separation processes * triboelectricity * particle separators Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.266, year: 2014

Proposal for implanting a magnetic stable isotope separator

International Nuclear Information System (INIS)

Lemos, O.F.

1988-07-01

The implantation of an electromagnetic isotope separator able to separate elements of mass from 20 to 250 a.m.u., with an enrichment factor from 10 to 200 times the initial concentration, depending on the elements, is proposed. The most suitable separator type for Brazilian CNEN, considering building installations and minimum conditions for the equipment facilities, the retinue chronogram, the infrastructure, and the personnel training for operation is defined. (M.C.K.) [pt

Multi trace element analysis of dry biological materials by neutron activation analysis including a chemical group separation

International Nuclear Information System (INIS)

Weers, C.A.

1980-01-01

The principles of activation analysis and the practical aspects of neutron activation analysis are outlined. The limits which are set to accuracy and precision are defined. The description of the evaporation process is summarised in terms of the half-volume. This quantity is then used to define the resolving power. The formulation is checked by radiotracer experiments. Dried animal blood is used as the testing material. The pretreatment of the samples and (the development of) the destruction-evaporation apparatus is described. Four successive devices were built and tested. The development of the successive adsorption steps with active charcoal, Al 2 O 3 and coprecipitation with Fe(OH) 3 is presented. Seven groups of about 25 elements in total can be determined this way. The results obtained for standard reference materials are summarized and compared with literature data. (Auth.)

Method for separating isotopes

International Nuclear Information System (INIS)

Jepson, B.E.

1976-01-01

The invention comprises a method for separating different isotopes of elements from each other by contacting a feed solution containing the different isotopes with a macrocyclic polyether to preferentially form a macrocyclic polyether complex with the lighter of the different isotopes. The macrocyclic polyether complex is then separated from the lighter isotope depleted feed solution. A chemical separation of isotopes is carried out in which a constant refluxing system permits a continuous countercurrent liquid-liquid extraction. (LL)

Traceability of Opuntia ficus-indica L. Miller by ICP-MS multi-element profile and chemometric approach.

Science.gov (United States)

Mottese, Antonio Francesco; Naccari, Clara; Vadalà, Rossella; Bua, Giuseppe Daniel; Bartolomeo, Giovanni; Rando, Rossana; Cicero, Nicola; Dugo, Giacomo

2018-01-01

Opuntia ficus-indica L. Miller fruits, particularly 'Ficodindia dell'Etna' of Biancavilla (POD), 'Fico d'india tradizionale di Roccapalumba' with protected brand and samples from an experimental field in Pezzolo (Sicily) were analyzed by inductively coupled plasma mass spectrometry in order to determine the multi-element profile. A multivariate chemometric approach, specifically principal component analysis (PCA), was applied to individuate how mineral elements may represent a marker of geographic origin, which would be useful for traceability. PCA has allowed us to verify that the geographical origin of prickly pear fruits is significantly influenced by trace element content, and the results found in Biancavilla PDO samples were linked to the geological composition of this volcanic areas. It was observed that two principal components accounted for 72.03% of the total variance in the data and, in more detail, PC1 explains 45.51% and PC2 26.52%, respectively. This study demonstrated that PCA is an integrated tool for the traceability of food products and, at the same time, a useful method of authentication of typical local fruits such as prickly pear. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

A site-specific and multi-element isotopic approach to origin inference of sugars in foods and beverages

International Nuclear Information System (INIS)

Martin, M.L.; Martin, G.J.; Guillou, C.

1991-01-01

A strategy is presented for the characterization of sugars according to their botanical origin. The samples fermented in standardized conditions can be described in the multi-dimensional space of the overall carbon isotope ratio of ethanol measured by isotope ratio mass spectrometry (IRMS) and of the specific hydrogen isotope parameters of the methyl and methylene sites derived from nuclear magnetic resonance investigation of site-specific natural isotope fractionation (SNIF-NMR method). In the comparison of natural juices, the deuterium and oxygen-18 parameters of water extracted from the juice and from the end fermentation medium also contain information on the origin of the product. The isotopic effects of the concentration processes leading to concentrated juices, musts and syrups can be estimated and taken into account in interpreting the data. The classification power of this multi-element and multi-site approach is illustrated by discriminant analyses involving selected isotopic variables associated with pineapple, apple and barley sugars, compared to beet and cane sugars which are common sources of enrichment. The ability of the method to detect adulteration by exogenous sugars is improved when environmental conditions can be taken into account. (authors)

Pollution and wet cleaning of separation nozzle systems for enrichment of uranium-235

International Nuclear Information System (INIS)

Bacher, W.; Bier, W.; Linder, N.

1980-06-01

Operational defects in separation nozzle plants resulting in air leaking into the system may cause permanent pollution of the narrow slits of the separation elements by products of the hydrolysis of UF 6 . The deposits may deteriorate the separation performance of the separation elements to such an extent that their further use for uranium enrichment is no longer feasible. Tests performed on commercial-scale separation element tubes indicated that the deposits can be removed by a wet chemical process effectively enough to restore the full separative power of the elements. The aspects of the technical application of the cleanup process are discussed. (orig.) [de

Multi-recycling of transuranic elements in a PWR assembly with reduced fuel rod diameter

International Nuclear Information System (INIS)

Chambers, Alex; Ragusa, Jean C.

2014-01-01

Highlights: • Study of multiple recycling passes of transuranic elements: (a) without exceeding 5 wt.% on U-235 enrichment; (b) using PWR fuel assemblies compatible with current reactor core internals. • Isotopic concentrations tend towards an equilibrium after 15 recycle passes, suggesting that thermal recycling may be continued beyond that point. • Radiotoxicity comparisons for once-through UOX, once-recycle MOX-Pu, and multiple recycle passes of MOX-PuNpAm and MOX-PuNpAmCm are presented. - Abstract: This paper examines the multi-recycling of transuranic (TRU) elements (Pu-Np-Am-Cm) in standard Pressurized Water Reactor (PWR) assemblies. The original feed of TRU comes from legacy spent UOX fuel. For all subsequent recycling passes, TRU elements from the previous generation are employed, supplemented by TRU from legacy UOX fuel, as needed. The design criteria include: 235 U enrichment requirements to remain below 5 w/o, TRU loading limits to avoid return to criticality under voided conditions, and assembly power peaking factors. In order to carry out multiple recycling passes within the design envelope, additional neutron moderation is required and achieved by reducing the fuel pellet diameter by about 13%, thus keeping the assembly design compatible with current PWR core internals. TRU transmutation rates and long-term ingestion radiotoxicity results are presented for 15 recycling passes and compared to standard UOX and MOX once-through cycles. The results also show that TRU fuel isotopics and radiotoxicity tend towards an equilibrium, enabling further additional recycling passes

Effects of Heat Input and Bead Generation Methods on Finite Element Analysis of Cylindrical Multi-Pass Welding Process of Metals

International Nuclear Information System (INIS)

Park, Won Dong; Bahn, Chi Bum; Kim, Ji Hoon

2017-01-01

In this study, a finite element analysis of a cylindrical multi-pass weldment for dissimilar metals was performed. The effects of the heat input method and weld bead generation method were considered. We compared two heat input methods: the heat flux method and the temperature method. We also compared two weld bead generation methods: the element birth method and the quiet element method. Although the results of the thermal analysis show deviations between the two heat input methods, the welding residual stresses were similar. Because the areas exposed to high temperature were similar and the strength of the material was very low in high temperature (above the 1000 ℃), the effects of the weld bead temperature were insignificant. The distributions of the welding residual stress were similar to each other. However, gaps and overlaps occurred on the welding boundary surfaces when the element birth method was applied. The quiet element method is more suitable for a large deformation model in order to simulate a more accurate weld shape.

Effects of Heat Input and Bead Generation Methods on Finite Element Analysis of Cylindrical Multi-Pass Welding Process of Metals

Energy Technology Data Exchange (ETDEWEB)

Park, Won Dong; Bahn, Chi Bum; Kim, Ji Hoon [Pusan Nat’l Univ., Busan (Korea, Republic of)

2017-06-15

In this study, a finite element analysis of a cylindrical multi-pass weldment for dissimilar metals was performed. The effects of the heat input method and weld bead generation method were considered. We compared two heat input methods: the heat flux method and the temperature method. We also compared two weld bead generation methods: the element birth method and the quiet element method. Although the results of the thermal analysis show deviations between the two heat input methods, the welding residual stresses were similar. Because the areas exposed to high temperature were similar and the strength of the material was very low in high temperature (above the 1000 ℃), the effects of the weld bead temperature were insignificant. The distributions of the welding residual stress were similar to each other. However, gaps and overlaps occurred on the welding boundary surfaces when the element birth method was applied. The quiet element method is more suitable for a large deformation model in order to simulate a more accurate weld shape.

A ''master key'' to chemical separation processes

International Nuclear Information System (INIS)

Madic, Ch.; Hill, C.

2002-01-01

One of the keys to sorting nuclear waste is extracting minor actinides - the most troublesome long-lived elements - from the flow of waste by separating them from lanthanides, which have very similar chemical properties to actinides, for possible transmutation into shorter-lived elements. Thanks to a European initiative coordinated by CEA, this key is now available: its name is Sanex. There now remains to develop tough, straightforward industrial processes to integrate it into a new nuclear waste management approach by 2005. Sanex joins the Diamex process, used for the combined separation of lanthanides and minor actinides from fission products. A third process, Sesame, designed to separate americium, completes the list of available separation processes. (authors)

The transuranium elements: From neptunium and plutonium to element 112

International Nuclear Information System (INIS)

Hoffman, D.C.

1996-01-01

Beginning in the 1930's, both chemists and physicists became interested in synthesizing new artificial elements. The first transuranium element, Np, was synthesized in 1940. Over the past six decades, 20 transuranium elements have been produced. A review of the synthesis is given. The procedure of naming the heavy elements is also discussed. It appears feasible to produce elements 113 and 114. With the Berkeley Gas-filled Separator, it should be possible to reach the superheavy elements in the region of the spherical Z=114 shell, but with fewer neutrons than the N=184 spherical shell. 57 refs, 6 figs

Separation process of heavy rare earth elements from xenotime ore

International Nuclear Information System (INIS)

Sri Sukmajaya; Tri Handini; Wahyu Rachmi Pusparini; Dwi Biyantoro

2016-01-01

Separation process of heavy rare earth elements from xenotime ore had been done. A 100 mesh of xenotime ore was upgrade using water, sodium silicate and oleic acid in pH 9. Mixed of slurry by air blown in room temperature along 30 minutes. The middle of slurry xenotime was be separated, then dried and so added soda caustic, potassium carbonate and ammonium dihydrogen phosphate. The mix was be homogenized then leached in furnace to 700°C temperature along 4 hours. The frits of leaching product would be leached using 1200 mL volume of water that made oxidation by HCl onto pH 4 by agitated heated in 70°C temperature. The mix was filtered, then solid settled was be dried and then to processed again in water HCl acidified leaching alike before until pH 4 with minimized HCl added least 2 mL. The solid settled filled into 1000 mL of beker glass, added HCl viscous in 300 mL volume, hydrogen peroxide and BaCl_2/Na_2SO_4/Na_2S then heated to 100°C temperature. Let in room temperature then was filtrated. The solid settled as ThSO_4/ThS, RaSO_4/RaS. The filtrate to be settled using 15g (NH_4)_2CO_3 in 100 mL volume of water while mixed until the solution reached pH 2. The solid settled was be dried, then into the filtrate added 10 mL volume of formic acid. The solid settled of filtration was be dried. The solution of filtrate to be settled using (NH_4)_2CO_3 until pH 4. The solid settled was be filtered and dried. The filtrate was be settled using oxalic acid. The analysis of standard of oxide rare earth had been done using XRF Am"2"4"1 source. Result of these process got 100 mesh xenotime upgrade those leached in 700°C along 4 hours used (NH_4)H_2PO_4 so HRE total lifted up from 4.31 to 8.16%. Resulted of HRE oxide yield was 17.76% in pH 2. HRE oxide yield in pH 4 was 38.45%, and HRE oxide yield was 6.38% as oxalic compound, so the total HRE oxide yield was 62.59%. (author)

Large scale multi-zone creep finite element modelling of a main steam line branch intersection

International Nuclear Information System (INIS)

Payten, Warwick

2006-01-01

A number of papers detail the non-linear creep finite element analysis of branch pieces. Predominately these models have incorporated only a single material zone representing the parent material. Multi-zone models incorporating weld material and heat affected zones have primarily been two-dimensional analyses, in part due to the large number of elements required to adequately represent all of the zones. This paper describes a non-linear creep analysis of a main steam line branch intersection using creep properties to represent the parent metal, weld metal, and heat affected zone (HAZ), the stress redistribution over 100,000 h is examined. The results show that the redistribution leads to a complex stress state, particularly at the heat affected zone. Although, there is damage on the external surface of the branch piece as expected, the results indicate that the damage would be more widespread through extensive sections of the heat affected zone. This would appear to indicate that the time between damage indications on the surface using techniques such as replication and full thickness damage may be more limited then previously expected

Multi-elemental analysis of aqueous geochemical samples by quadrupole inductively coupled plasma-mass spectrometry (ICP-MS)

Science.gov (United States)

Wolf, Ruth E.; Adams, Monique

2015-01-01

Typically, quadrupole inductively coupled plasma-mass spectrometry (ICP-MS) is used to determine as many as 57 major, minor, and trace elements in aqueous geochemical samples, including natural surface water and groundwater, acid mine drainage water, and extracts or leachates from geological samples. The sample solution is aspirated into the inductively coupled plasma (ICP) which is an electrodeless discharge of ionized argon gas at a temperature of approximately 6,000 degrees Celsius. The elements in the sample solution are subsequently volatilized, atomized, and ionized by the ICP. The ions generated are then focused and introduced into a quadrupole mass filter which only allows one mass to reach the detector at a given moment in time. As the settings of the mass analyzer change, subsequent masses are allowed to impact the detector. Although the typical quadrupole ICP-MS system is a sequential scanning instrument (determining each mass separately), the scan speed of modern instruments is on the order of several thousand masses per second. Consequently, typical total sample analysis times of 2–3 minutes are readily achievable for up to 57 elements.

Multi-resolution simulation of focused ultrasound propagation through ovine skull from a single-element transducer

Science.gov (United States)

Yoon, Kyungho; Lee, Wonhye; Croce, Phillip; Cammalleri, Amanda; Yoo, Seung-Schik

2018-05-01

Transcranial focused ultrasound (tFUS) is emerging as a non-invasive brain stimulation modality. Complicated interactions between acoustic pressure waves and osseous tissue introduce many challenges in the accurate targeting of an acoustic focus through the cranium. Image-guidance accompanied by a numerical simulation is desired to predict the intracranial acoustic propagation through the skull; however, such simulations typically demand heavy computation, which warrants an expedited processing method to provide on-site feedback for the user in guiding the acoustic focus to a particular brain region. In this paper, we present a multi-resolution simulation method based on the finite-difference time-domain formulation to model the transcranial propagation of acoustic waves from a single-element transducer (250 kHz). The multi-resolution approach improved computational efficiency by providing the flexibility in adjusting the spatial resolution. The simulation was also accelerated by utilizing parallelized computation through the graphic processing unit. To evaluate the accuracy of the method, we measured the actual acoustic fields through ex vivo sheep skulls with different sonication incident angles. The measured acoustic fields were compared to the simulation results in terms of focal location, dimensions, and pressure levels. The computational efficiency of the presented method was also assessed by comparing simulation speeds at various combinations of resolution grid settings. The multi-resolution grids consisting of 0.5 and 1.0 mm resolutions gave acceptable accuracy (under 3 mm in terms of focal position and dimension, less than 5% difference in peak pressure ratio) with a speed compatible with semi real-time user feedback (within 30 s). The proposed multi-resolution approach may serve as a novel tool for simulation-based guidance for tFUS applications.

A novel scatter separation method for multi-energy x-ray imaging

Science.gov (United States)

Sossin, A.; Rebuffel, V.; Tabary, J.; Létang, J. M.; Freud, N.; Verger, L.

2016-06-01

X-ray imaging coupled with recently emerged energy-resolved photon counting detectors provides the ability to differentiate material components and to estimate their respective thicknesses. However, such techniques require highly accurate images. The presence of scattered radiation leads to a loss of spatial contrast and, more importantly, a bias in radiographic material imaging and artefacts in computed tomography (CT). The aim of the present study was to introduce and evaluate a partial attenuation spectral scatter separation approach (PASSSA) adapted for multi-energy imaging. This evaluation was carried out with the aid of numerical simulations provided by an internal simulation tool, Sindbad-SFFD. A simplified numerical thorax phantom placed in a CT geometry was used. The attenuation images and CT slices obtained from corrected data showed a remarkable increase in local contrast and internal structure detectability when compared to uncorrected images. Scatter induced bias was also substantially decreased. In terms of quantitative performance, the developed approach proved to be quite accurate as well. The average normalized root-mean-square error between the uncorrected projections and the reference primary projections was around 23%. The application of PASSSA reduced this error to around 5%. Finally, in terms of voxel value accuracy, an increase by a factor  >10 was observed for most inspected volumes-of-interest, when comparing the corrected and uncorrected total volumes.

On-line separation of refractory hafnium and tantalum isotopes at the ISOCELE separator

CERN Document Server

Liang, C F; Obert, J; Paris, P; Putaux, J C

1981-01-01

By chemical evaporation technique, neutron deficient hafnium nuclei have been on-line separated at the ISOCELE facility, from the isobar rare-earth elements, in the metal-fluoride HfF/sub 3//sup +/ ion form. Half-lives of /sup 162-165/Hf have been measured. Similarly, tantalum has been selectively separated on the TaF/sub 4//sup +/ form. (4 refs) .

Rayleigh-based, multi-element coral thermometry: A biomineralization approach to developing climate proxies

Science.gov (United States)

Gaetani, G.A.; Cohen, A.L.; Wang, Z.; Crusius, John

2011-01-01

This study presents a new approach to coral thermometry that deconvolves the influence of water temperature on skeleton composition from that of “vital effects”, and has the potential to provide estimates of growth temperatures that are accurate to within a few tenths of a degree Celsius from both tropical and cold-water corals. Our results provide support for a physico-chemical model of coral biomineralization, and imply that Mg2+ substitutes directly for Ca2+ in biogenic aragonite. Recent studies have identified Rayleigh fractionation as an important influence on the elemental composition of coral skeletons. Daily, seasonal and interannual variations in the amount of aragonite precipitated by corals from each “batch” of calcifying fluid can explain why the temperature dependencies of elemental ratios in coral skeleton differ from those of abiogenic aragonites, and are highly variable among individual corals. On the basis of this new insight into the origin of “vital effects” in coral skeleton, we developed a Rayleigh-based, multi-element approach to coral thermometry. Temperature is resolved from the Rayleigh fractionation signal by combining information from multiple element ratios (e.g., Mg/Ca, Sr/Ca, Ba/Ca) to produce a mathematically over-constrained system of Rayleigh equations. Unlike conventional coral thermometers, this approach does not rely on an initial calibration of coral skeletal composition to an instrumental temperature record. Rather, considering coral skeletogenesis as a biologically mediated, physico-chemical process provides a means to extract temperature information from the skeleton composition using the Rayleigh equation and a set of experimentally determined partition coefficients. Because this approach is based on a quantitative understanding of the mechanism that produces the “vital effect” it should be possible to apply it both across scleractinian species and to corals growing in vastly different environments. Where

Development of Multi-Scale Finite Element Analysis Codes for High Formability Sheet Metal Generation

International Nuclear Information System (INIS)

Nnakamachi, Eiji; Kuramae, Hiroyuki; Ngoc Tam, Nguyen; Nakamura, Yasunori; Sakamoto, Hidetoshi; Morimoto, Hideo

2007-01-01

In this study, the dynamic- and static-explicit multi-scale finite element (F.E.) codes are developed by employing the homogenization method, the crystalplasticity constitutive equation and SEM-EBSD measurement based polycrystal model. These can predict the crystal morphological change and the hardening evolution at the micro level, and the macroscopic plastic anisotropy evolution. These codes are applied to analyze the asymmetrical rolling process, which is introduced to control the crystal texture of the sheet metal for generating a high formability sheet metal. These codes can predict the yield surface and the sheet formability by analyzing the strain path dependent yield, the simple sheet forming process, such as the limit dome height test and the cylindrical deep drawing problems. It shows that the shear dominant rolling process, such as the asymmetric rolling, generates ''high formability'' textures and eventually the high formability sheet. The texture evolution and the high formability of the newly generated sheet metal experimentally were confirmed by the SEM-EBSD measurement and LDH test. It is concluded that these explicit type crystallographic homogenized multi-scale F.E. code could be a comprehensive tool to predict the plastic induced texture evolution, anisotropy and formability by the rolling process and the limit dome height test analyses

Effects of Process Parameters on Copper Powder Compaction Process Using Multi-Particle Finite Element Method

Science.gov (United States)

Güner, F.; Sofuoğlu, H.

2018-01-01

Powder metallurgy (PM) has been widely used in several industries; especially automotive and aerospace industries and powder metallurgy products grow up every year. The mechanical properties of the final product that is obtained by cold compaction and sintering in powder metallurgy are closely related to the final relative density of the process. The distribution of the relative density in the die is affected by parameters such as compaction velocity, friction coefficient and temperature. Moreover, most of the numerical studies utilizing finite element approaches treat the examined environment as a continuous media with uniformly homogeneous porosity whereas Multi-Particle Finite Element Method (MPFEM) treats every particles as an individual body. In MPFEM, each of the particles can be defined as an elastic- plastic deformable body, so the interactions of the particles with each other and the die wall can be investigated. In this study, each particle was modelled and analyzed as individual deformable body with 3D tetrahedral elements by using MPFEM approach. This study, therefore, was performed to investigate the effects of different temperatures and compaction velocities on stress distribution and deformations of copper powders of 200 µm-diameter in compaction process. Furthermore, 3-D MPFEM model utilized von Mises material model and constant coefficient of friction of μ=0.05. In addition to MPFEM approach, continuum modelling approach was also performed for comparison purposes.

Development of an Efficient Meso- scale Multi-phase Flow Solver in Nuclear Applications

Energy Technology Data Exchange (ETDEWEB)

Lee, Taehun [City Univ. (CUNY), NY (United States)

2015-10-20

The proposed research aims at formulating a predictive high-order Lattice Boltzmann Equation for multi-phase flows relevant to nuclear energy related application - namely, saturated and sub-cooled boiling in reactors, and liquid- liquid mixing and extraction for fuel cycle separation. An efficient flow solver will be developed based on the Finite Element based Lattice Boltzmann Method (FE- LBM), accounting for phase-change heat transfer and capable of treating multiple phases over length scales from the submicron to the meter. A thermal LBM will be developed in order to handle adjustable Prandtl number, arbitrary specific heat ratio, a wide range of temperature variations, better numerical stability during liquid-vapor phase change, and full thermo-hydrodynamic consistency. Two-phase FE-LBM will be extended to liquid–liquid–gas multi-phase flows for application to high-fidelity simulations building up from the meso-scale up to the equipment sub-component scale. While several relevant applications exist, the initial applications for demonstration of the efficient methods to be developed as part of this project include numerical investigations of Critical Heat Flux (CHF) phenomena in nuclear reactor fuel bundles, and liquid-liquid mixing and interfacial area generation for liquid-liquid separations. In addition, targeted experiments will be conducted for validation of this advanced multi-phase model.

Multi-color and artistic dithering

OpenAIRE

Ostromoukhov, Victor; Hersch, Roger D.

1999-01-01

A multi-color dithering algorithm is proposed, which converts a barycentric combination of color intensities into a multi-color non-overlapping surface coverage. Multi-color dithering is a generalization of standard bi-level dithering. Combined with tetrahedral color separation, multi-color dithering makes it possible to print images made of a set of non-standard inks. In contrast to most previous color halftoning methods, multi-color dithering ensures by construction that the different selec...

Determination of 25 trace impurity elements in U3O8 by horizontal ICP-AES after separation with TBP levextrel resin chromatography

International Nuclear Information System (INIS)

Guan Jingsu; Shi Youqing; Gao Binghua; Liu Yingmei

1988-01-01

A method for the determination of Al, As, Ba, Be, Bi, Ca, Cd, Cu, Co, Cr, Fe, Mg, Mn, Mo, Ni, P, Pb, Ru, Sb, Sn, Sr, Ti, V, W and Zn 25 trace elements in U 3 O 8 is reported. The sample is dissolved in HNO 3 or HNO 3 -HCLO 4 -HF and the uranium is separated by TBP Levextrel resin chromatogyaphy. The impurity elements containing in the aquaous phase are determined by horizontal ICp-AES method. With a sample of 300 mg, the detection limit for all the 25 elements is in the range of 0.01∼5ppm, the recovery is in the range of 82∼ 121%, the determination precision (RSD) is less than ±13%. 18 trace elements in reference material of U 3 O 8 prepared in China are determined, the values obtained well with the values of overall median of accepted laboratory means

Ultraviolet-light-induced multi-physics behaviors of 0–3 polarized transparent PLZT plates: II. Finite element analysis and validation

International Nuclear Information System (INIS)

Luo, Quantian; Tong, Liyong

2011-01-01

This paper presents a novel finite element formulation for 0–3 polarized PbLaZrTi (PLZT) plates and a comparison of the predicted and measured bending displacements. The coupled multi-physics fields and Hamilton's principle for piezoelectric (PZT) materials are first extended to PLZT ceramics by including the anomalous photovoltaic and photo-thermal effects. The photo-induced non-uniform electrical field and mechanical strains across the thickness are modeled in the present finite element formulation for 0–3 polarized PLZT plates, and the associated actuator and sensor equations are derived. The transverse displacements of a 0–3 polarized PLZT plate are predicted using the present finite element formulation and compared with the measured data given in part I. A reasonably good correlation is noted for the transverse displacements at the ten measurement points

[Ultra-Fine Pressed Powder Pellet Sample Preparation XRF Determination of Multi-Elements and Carbon Dioxide in Carbonate].

Science.gov (United States)

Li, Xiao-li; An, Shu-qing; Xu, Tie-min; Liu, Yi-bo; Zhang, Li-juan; Zeng, Jiang-ping; Wang, Na

2015-06-01

The main analysis error of pressed powder pellet of carbonate comes from particle-size effect and mineral effect. So in the article in order to eliminate the particle-size effect, the ultrafine pressed powder pellet sample preparation is used to the determination of multi-elements and carbon-dioxide in carbonate. To prepare the ultrafine powder the FRITSCH planetary Micro Mill machine and tungsten carbide media is utilized. To conquer the conglomeration during the process of grinding, the wet grinding is preferred. The surface morphology of the pellet is more smooth and neat, the Compton scatter effect is reduced with the decrease in particle size. The intensity of the spectral line is varied with the change of the particle size, generally the intensity of the spectral line is increased with the decrease in the particle size. But when the particle size of more than one component of the material is decreased, the intensity of the spectral line may increase for S, Si, Mg, or decrease for Ca, Al, Ti, K, which depend on the respective mass absorption coefficient . The change of the composition of the phase with milling is also researched. The incident depth of respective element is given from theoretical calculation. When the sample is grounded to the particle size of less than the penetration depth of all the analyte, the effect of the particle size on the intensity of the spectral line is much reduced. In the experiment, when grounded the sample to less than 8 μm(d95), the particle-size effect is much eliminated, with the correction method of theoretical α coefficient and the empirical coefficient, 14 major, minor and trace element in the carbonate can be determined accurately. And the precision of the method is much improved with RSD element, the fluorescence yield is low and the interference is serious. With the manual multi-layer crystal PX4, coarse collimator, empirical correction, X-ray spectrometer can be used to determine the carbon dioxide in the carbonate

Multi-trace elements level in drinking water and the prevalence of multi-chronic arsenical poisoning in residents in the west area of Iran

International Nuclear Information System (INIS)

Barati, A.H.; Maleki, A.; Alasvand, M.

2010-01-01

First, we determined the levels of 8 trace elements (As, Se, Hg, Cd, Ag, Mn, Cr and Pb) in 530 village drinking water sources by graphite furnace or flame atomic absorption spectroscopy method, in Kurdistan Province in the west of Iran. The results showed that the level of As, Cd and Se in 28 village drinking water sources exceeded WHO or National Standard limits. The levels of concentration of arsenic in drinking water ranged from 42 to 1500 μg/L. Then in a cross-sectional survey, 587 people from 211 households were chosen for clinical examinations of multi-chronic arsenical poisoning including pigment disorders, keratosis of palms and soles, Mee's line in fingers and nails and the gangrene as a systemic manifestation. Of 587 participants, 180 (30.7%) participants were affected by representing the type of chronic arsenical poisoning. The prevalence of Mee's line, keratosis, and pigment disorders were 86.1%, 77.2% and 67.8% respectively. Therefore, the prevalence of Mee's line between inhabitants was higher than the other disorders. The results show a strong linear relationship between arsenic exposure and occurrence of multi-chronic arsenical poisoning (R 2 = 0.76). The association between age for more than 40 years and gender for more than 60 years with chronic arsenical poisoning is significant (p < 0.05). Also, there is a relationship between subjects who were affected with disorders and duration of living in the village. Except for gangrene disorder, the odds ratio of prevalence of other disorders with arsenic exposure level in drinking water show a highly significant relationship between arsenic content and the risk of chronic disorders (p < 0.01). These results confirm the need to further study trace elements in drinking waters, food products and other samples in this area and the relationship to other chronic diseases arising out of arsenicosis.

Thorium and uranium separation from Rare Earth complex minerals in Turkey

International Nuclear Information System (INIS)

Uzmen, R.

2014-01-01

Conclusion: • Thorium and uranium separation from a REEs solution is possible in by using simple traditional methods. • Main advantage of this method is to separate with high recovery yield uraniumand almost completely thorium which is an undesirable element due to its radioactive property in the different REEs group or individual REE. • Separation of thorium before any other step of REE’s group or individual element separation is crucial. • By using this flowsheet it would be possible to obtain uranium and other valuable elements (Zr, Ti, etc.) as coproducts of REEs. • Another important point, during REEs production, it is avoided to accumalate U and Th contaminated process wastes. • Thus, in the contrary, radioactive elements are refined and contained for safe storage.

Dynamic Computational Model of Symptomatic Bacteremia to Inform Bacterial Separation Treatment Requirements.

Directory of Open Access Journals (Sweden)

Sinead E Miller

Full Text Available The rise of multi-drug resistance has decreased the effectiveness of antibiotics, which has led to increased mortality rates associated with symptomatic bacteremia, or bacterial sepsis. To combat decreasing antibiotic effectiveness, extracorporeal bacterial separation approaches have been proposed to capture and separate bacteria from blood. However, bacteremia is dynamic and involves host-pathogen interactions across various anatomical sites. We developed a mathematical model that quantitatively describes the kinetics of pathogenesis and progression of symptomatic bacteremia under various conditions, including bacterial separation therapy, to better understand disease mechanisms and quantitatively assess the biological impact of bacterial separation therapy. Model validity was tested against experimental data from published studies. This is the first multi-compartment model of symptomatic bacteremia in mammals that includes extracorporeal bacterial separation and antibiotic treatment, separately and in combination. The addition of an extracorporeal bacterial separation circuit reduced the predicted time of total bacteria clearance from the blood of an immunocompromised rodent by 49%, compared to antibiotic treatment alone. Implementation of bacterial separation therapy resulted in predicted multi-drug resistant bacterial clearance from the blood of a human in 97% less time than antibiotic treatment alone. The model also proposes a quantitative correlation between time-dependent bacterial load among tissues and bacteremia severity, analogous to the well-known 'area under the curve' for characterization of drug efficacy. The engineering-based mathematical model developed may be useful for informing the design of extracorporeal bacterial separation devices. This work enables the quantitative identification of the characteristics required of an extracorporeal bacteria separation device to provide biological benefit. These devices will potentially

Studies on the separation and purification of strontium from the highly radioactive waste flow of fuel element reprocessing

International Nuclear Information System (INIS)

Tuerker, A.

1989-10-01

The quantity of spent fuel elements is increasing due to the extended peaceful uses of nuclear energy. Of the numerous fission products, strontium has an interesting application potential as a radiation or energy source for utilization in various industrial fields. A necessary condition for its use is its isolation in high radiochemical purity from the highly radioactive waste flow of the Purex process. In the present study, precipitation and coprecipitation reactions, and in particular ion exchange reactions, were chosen from among the various possible chemical and physical separation methods and examined with respect to their suitability for a selective separation of strontium from the other fission products. In selecting separation materials, particularly with respect to radiation resistance, thermal stability and selectivity, polyantimonic acid proved to be the best absorbent (even in a very acid medium) for strontium. Furthermore, the behaviour of the most important radionuclides was studied with respect to the denitration reaction from a 5 molar nitric acid solution. On the basis of the high demands made on the purity of the product, a method was developed by combining lead sulphate carrier precipitation with an ion exchange reaction on polyantimonic acid and is shown in a flow chart. (orig.) [de

Multi-element measurements in mexican cigarette tobacco

International Nuclear Information System (INIS)

Vega-Carrillo, H.R.; Texas Univ., Austin, TX; Zacatecas Univ.; Iskander, F.Y.; Manzanares-Acuna, E.

1995-01-01

The concentration of 21 elements in cigarette tobacco in nine different brands manufactured and commercially available in Mexico has been determined using neutron activation analysis. The concentration range of the measured elements (in μg g -1 ) were: As, (four brands) <0.55-3.24; Ba, 64-251; Br, (four brands) 49-136; Ce, <0.3-1.7; Co, 0.29-0.55, Cr, <0.8-2.4; Cs, 0.091-0.40; Eu, <0.03; Fe, 420-680; Hf, <0.03-0.13; K, (four brands) 18300-40300; La, (four brands) < 0.2-0.66; Na, (four brands) 309-566; Rb, 19-50; Sb, <0.7; Sc, 0.13-0.22; Se, <0.7; Sm, (four brands) 0.07-0.14; Sr, 227-472; Th, < 0.1-0.17 and Zn, 14-56. The results are compared with the literature values for the concentration of the above elements in cigarette tobacco from other countries. (author) 18 refs.; 2 tabs

Multi-recycling of transuranic elements in a PWR assembly with reduced fuel rod diameter

Energy Technology Data Exchange (ETDEWEB)

Chambers, Alex, E-mail: acchamb@gmail.com; Ragusa, Jean C., E-mail: jean.ragusa@tamu.edu

2014-04-01

Highlights: • Study of multiple recycling passes of transuranic elements: (a) without exceeding 5 wt.% on U-235 enrichment; (b) using PWR fuel assemblies compatible with current reactor core internals. • Isotopic concentrations tend towards an equilibrium after 15 recycle passes, suggesting that thermal recycling may be continued beyond that point. • Radiotoxicity comparisons for once-through UOX, once-recycle MOX-Pu, and multiple recycle passes of MOX-PuNpAm and MOX-PuNpAmCm are presented. - Abstract: This paper examines the multi-recycling of transuranic (TRU) elements (Pu-Np-Am-Cm) in standard Pressurized Water Reactor (PWR) assemblies. The original feed of TRU comes from legacy spent UOX fuel. For all subsequent recycling passes, TRU elements from the previous generation are employed, supplemented by TRU from legacy UOX fuel, as needed. The design criteria include: {sup 235}U enrichment requirements to remain below 5 w/o, TRU loading limits to avoid return to criticality under voided conditions, and assembly power peaking factors. In order to carry out multiple recycling passes within the design envelope, additional neutron moderation is required and achieved by reducing the fuel pellet diameter by about 13%, thus keeping the assembly design compatible with current PWR core internals. TRU transmutation rates and long-term ingestion radiotoxicity results are presented for 15 recycling passes and compared to standard UOX and MOX once-through cycles. The results also show that TRU fuel isotopics and radiotoxicity tend towards an equilibrium, enabling further additional recycling passes.

Cesium and Strontium Separation Technologies Literature Review

Energy Technology Data Exchange (ETDEWEB)

T. A. Todd; T. A. Todd; J. D. Law; R. S. Herbst

2004-03-01

Integral to the Advanced Fuel Cycle Initiative (AFCI) Program’s proposed closed nuclear fuel cycle, the fission products cesium and strontium in the dissolved spent nuclear fuel stream are to be separated and managed separately. A comprehensive literature survey is presented to identify cesium and strontium separation technologies that have the highest potential and to focus research and development efforts on these technologies. Removal of these high-heat-emitting fission products reduces the radiation fields in subsequent fuel cycle reprocessing streams and provides a significant short-term (100 yr) heat source reduction in the repository. This, along with separation of actinides, may provide a substantial future improvement in the amount of fuel that could be stored in a geologic repository. The survey and review of the candidate cesium and strontium separation technologies are presented herein. Because the AFCI program intends to manage cesium and strontium together, technologies that simultaneously separate both elements are of the greatest interest, relative to technologies that separate only one of the two elements.

Fusion-evaporation studies with the Super Separator spectrometer (S3 at Spiral2

Directory of Open Access Journals (Sweden)

Déchery F.

2011-10-01

Full Text Available The Super Separator Spectrometer S3 is a device designed for experiments with the very high intensity stable ion beam of the superconducting linear accelerator of the SPIRAL2 facility. Its Physics goals cover the study of radioactive ions produced by fusion-evaporation reactions, like superheavy elements or neutron deficient nuclei close to the proton drip line, but also neutron rich nuclei produced by multi-nucleon transfer reactions as well as ion-ion atomic interactions. It is composed of a two-step separator, with a momentum achromat followed by a mass spectrometer. Superconducting multipole triplets, combining quadruple, sextuple and octupole fields, allow a combination of high transmission and mass resolution. A specific open multipole has been designed to stop the high beam power at the first momentum dispersive plane. A decay spectroscopy detection set-up or a low energy branch can be coupled to S3 for a wide range of studies.

A high-sensitive and quantitative in-line monitoring method for transplutonium elements separation processes

International Nuclear Information System (INIS)

Zhu Rongbao; Wang Shiju; Xu Yingpu; Zhang Zengrui

1986-04-01

A high-sensitive monitoring device and a quantitative analys technigue for transplutonium elements separation processes are described. X-ray and low energy γ-ray are measured by means of a scintillation monitor with two NaI(Tl) thin crystals. The α spectra of the fluents of ion-exchange column is measured by means of Si(Au) surface barrier in-line monitor. The construction of the monitors, auxiliary electronics, investigation result for the α spectra character of thick source and the calibration method were described. The determination results for extracting process of 243 Am and 244 Cm by ion-exchange chromatography were given. The sensitivity of total adding amount for 243 Am using the 4π scintillation monitor is better than 0.1 μCi. The precision of 243 Am and 244 Cm concentration determination using Si(Au) monitor is +- 5%. The precision of the two metals contents in containers is about +- 10%

A problem in gravimetric method for the determination of rare earth elements as oxide after the fluoride separation

International Nuclear Information System (INIS)

Takada, Kunio

1979-01-01

For the gravimetric determination of lanthanum, it was precipitated as fluoride and converted to oxide by igniting (ca. 930 0 C) in a town gas flame. However, the oxidation of lanthanum fluoride by ignition was incomplete, the major part of the precipitate being converted to oxyfluoride (LaOF) and a mixture of oxide and oxyfluoride resulted. Therefore, analytical results were generally (5 -- 7)% higher than theoretically expected. The lanthanum fluoride became converted into the oxide by repeating ignition (ca. 1070 0 C) three times, each for (30 -- 40)min. However, the weight was lower than that of the corresponding sesquioxide, La 2 O 3 . Except for ytterbium and lutetium, gravimetric results as oxides for the other rare earth elements (Y, Pr, Nd, Sm, Eu and Gd) were higher than theoretical values. Therefore, the precipitation of the rare earth elements as fluoride and the subsequent determination as oxide by ignition of the fluoride could not be recommended as the gravimetric method for the rare earths. In order to obtain accurate results for major to minor amounts of the rare earth elements, an EDTA titration at pH 6 should be used after the dissolution of fluoride in acid, if the fluoride precipitation separation is involved. (author)

The Multi-Template Molecularly Imprinted Polymer Based on SBA-15 for Selective Separation and Determination of Panax notoginseng Saponins Simultaneously in Biological Samples

Directory of Open Access Journals (Sweden)

Chenghong Sun

2017-11-01

Full Text Available The feasible, reliable and selective multi-template molecularly imprinted polymers (MT-MIPs based on SBA-15 (SBA-15@MT-MIPs for the selective separation and determination of the trace level of ginsenoside Rb1 (Rb1, ginsenoside Rg1 (Rg1 and notoginsenoside R1 (R1 simultaneously from biological samples were developed. The polymers were constructed by SBA-15 as support, Rb1, Rg1, R1 as multi-template, acrylamide (AM as functional monomer and ethylene glycol dimethacrylate (EGDMA as cross-linker. The new synthetic SBA-15@MT-MIPs were satisfactorily applied to solid-phase extraction (SPE coupled with high performance liquid chromatography (HPLC for the separation and determination of trace Rb1, Rg1 and R1 in plasma samples. Under the optimized conditions, the limits of detection (LODs and quantitation (LOQs of the proposed method for Rb1, Rg1 and R1 were in the range of 0.63–0.75 ng·mL−1 and 2.1–2.5 ng·mL−1, respectively. The recoveries of R1, Rb1 and Rg1 were obtained between 93.4% and 104.3% with relative standard deviations (RSDs in the range of 3.3–4.2%. All results show that the obtained SBA-15@MT-MIPs could be a promising prospect for the practical application in the selective separation and enrichment of trace Panax notoginseng saponins (PNS in the biological samples.

Resonance ionization laser ion sources for on-line isotope separators (invited)

International Nuclear Information System (INIS)

Marsh, B. A.

2014-01-01

A Resonance Ionization Laser Ion Source (RILIS) is today considered an essential component of the majority of Isotope Separator On Line (ISOL) facilities; there are seven laser ion sources currently operational at ISOL facilities worldwide and several more are under development. The ionization mechanism is a highly element selective multi-step resonance photo-absorption process that requires a specifically tailored laser configuration for each chemical element. For some isotopes, isomer selective ionization may even be achieved by exploiting the differences in hyperfine structures of an atomic transition for different nuclear spin states. For many radioactive ion beam experiments, laser resonance ionization is the only means of achieving an acceptable level of beam purity without compromising isotope yield. Furthermore, by performing element selection at the location of the ion source, the propagation of unwanted radioactivity downstream of the target assembly is reduced. Whilst advances in laser technology have improved the performance and reliability of laser ion sources and broadened the range of suitable commercially available laser systems, many recent developments have focused rather on the laser/atom interaction region in the quest for increased selectivity and/or improved spectral resolution. Much of the progress in this area has been achieved by decoupling the laser ionization from competing ionization processes through the use of a laser/atom interaction region that is physically separated from the target chamber. A new application of gas catcher laser ion source technology promises to expand the capabilities of projectile fragmentation facilities through the conversion of otherwise discarded reaction fragments into high-purity low-energy ion beams. A summary of recent RILIS developments and the current status of laser ion sources worldwide is presented

Investigations on the application of the ion-exchanger SRAFION NMRR for the enrichment and separation of uranium and other trace elements from sea water

International Nuclear Information System (INIS)

Ochsenkuehn-Petropulu, M.; Parissakis, G.

1985-01-01

It can be demonstrated, in batch and continuous flow experiments that the ion-exchanger SRAFION NMRR is suitable for the preconcentration and separation of uranium and other trace elements (such as Mo, V, Ag, Cr, Cu, Fe, Mn, Ni, Pb and Zn) from sea water. Among the different eluates, 0.5 N HNO 3 was selected. Uranium was extracted from the eluate with 0.1 M TOPO/cyclohexane and analysed in the organic extract by differential-pulse polarography, while the other elements were directly determined in the eluate by AAS. It was possible to determine the above mentioned trace elements by this absorption-elution process in the sea water of the Isthmus of Corinth area, Greece. (orig.) [de

Multi-element analyses of earthworms for radioecology and ecotoxicology

International Nuclear Information System (INIS)

Yoshida, S.; Peijnenburg, W.; Muramatsu, Y.

2004-01-01

Increasing concern about environmental radiation protection has raised awareness that more information is required on the transfer and accumulation of radionuclides in the biological compartments of ecosystems. ICRP (International Commission on Radiological Protection) selected earthworm as one of the reference organisms in their radiation protection recommendations. Earthworms play an important role in ecosystems, and might be a good indicator of soil contamination and its effect on the ecosystem. The elemental composition of earthworms gives useful information on background levels and possible accumulation of metals as well as related radionuclides. In addition, a change of the elemental composition itself might be a possible indicator of the effect on the earthworm and/or ecosystem. However, data for the elemental composition of earthworms are limited except for some specific heavy metals such as Cd, Zn, Pb and Cu. In this study, earthworms and their growth media were analyzed for more than 30 elements, including radionuclide related elements such as Cs, Sr, Th and U, in order to obtain the basic information on the transfer parameters of the elements. The earthworms analyzed were fed in the laboratory or collected in the environment. The concentrations and transfer factors of the elements were determined both for laboratory and natural conditions. The controlling factors on the transfer parameters such as the bioavailability of the elements in the soils will also be discussed. (author)

Velocity Profile measurements in two-phase flow using multi-wave sensors

Science.gov (United States)

Biddinika, M. K.; Ito, D.; Takahashi, H.; Kikura, H.; Aritomi, M.

2009-02-01

Two-phase flow has been recognized as one of the most important phenomena in fluid dynamics. In addition, gas-liquid two-phase flow appears in various industrial fields such as chemical industries and power generations. In order to clarify the flow structure, some flow parameters have been measured by using many effective measurement techniques. The velocity profile as one of the important flow parameter, has been measured by using ultrasonic velocity profile (UVP) technique. This technique can measure velocity distributions along a measuring line, which is a beam formed by pulse ultrasounds. Furthermore, a multi-wave sensor can measure the velocity profiles of both gas and liquid phase using UVP method. In this study, two types of multi-wave sensors are used. A sensor has cylindrical shape, and another one has square shape. The piezoelectric elements of each sensor have basic frequencies of 8 MHz for liquid phase and 2 MHz for gas phase, separately. The velocity profiles of air-water bubbly flow in a vertical rectangular channel were measured by using these multi-wave sensors, and the validation of the measuring accuracy was performed by the comparison between the velocity profiles measured by two multi-wave sensors.

Velocity Profile measurements in two-phase flow using multi-wave sensors

International Nuclear Information System (INIS)

Biddinika, M K; Ito, D; Takahashi, H; Kikura, H; Aritomi, M

2009-01-01

Two-phase flow has been recognized as one of the most important phenomena in fluid dynamics. In addition, gas-liquid two-phase flow appears in various industrial fields such as chemical industries and power generations. In order to clarify the flow structure, some flow parameters have been measured by using many effective measurement techniques. The velocity profile as one of the important flow parameter, has been measured by using ultrasonic velocity profile (UVP) technique. This technique can measure velocity distributions along a measuring line, which is a beam formed by pulse ultrasounds. Furthermore, a multi-wave sensor can measure the velocity profiles of both gas and liquid phase using UVP method. In this study, two types of multi-wave sensors are used. A sensor has cylindrical shape, and another one has square shape. The piezoelectric elements of each sensor have basic frequencies of 8 MHz for liquid phase and 2 MHz for gas phase, separately. The velocity profiles of air-water bubbly flow in a vertical rectangular channel were measured by using these multi-wave sensors, and the validation of the measuring accuracy was performed by the comparison between the velocity profiles measured by two multi-wave sensors.

Extended depth of field integral imaging using multi-focus fusion

Science.gov (United States)

Piao, Yongri; Zhang, Miao; Wang, Xiaohui; Li, Peihua

2018-03-01

In this paper, we propose a new method for depth of field extension in integral imaging by realizing the image fusion method on the multi-focus elemental images. In the proposed method, a camera is translated on a 2D grid to take multi-focus elemental images by sweeping the focus plane across the scene. Simply applying an image fusion method on the elemental images holding rich parallax information does not work effectively because registration accuracy of images is the prerequisite for image fusion. To solve this problem an elemental image generalization method is proposed. The aim of this generalization process is to geometrically align the objects in all elemental images so that the correct regions of multi-focus elemental images can be exacted. The all-in focus elemental images are then generated by fusing the generalized elemental images using the block based fusion method. The experimental results demonstrate that the depth of field of synthetic aperture integral imaging system has been extended by realizing the generation method combined with the image fusion on multi-focus elemental images in synthetic aperture integral imaging system.

Simultaneous Multi-Element Electrothermal Atomic Absorption ...

African Journals Online (AJOL)

width of transmittance profile 120 pm, a linear CCD array attached to a PC and a tube atomizer furnished with a carbon fibre collector. In the experiments simultaneous determination of 18 elements was performed in the mixed solutions at the mg ...

Effective enhancement of gas separation performance in mixed matrix membranes using core/shell structured multi-walled carbon nanotube/graphene oxide nanoribbons

Science.gov (United States)

Xue, Qingzhong; Pan, Xinglong; Li, Xiaofang; Zhang, Jianqiang; Guo, Qikai

2017-02-01

Novel core/shell structured multi-walled carbon nanotube/graphene oxide nanoribbons (MWCNT@GONRs) nanohybrids were successfully prepared using a modified chemical longitudinal unzipping method. Subsequently, the MWCNT@GONRs nanohybrids were used as fillers to enhance the gas separation performance of polyimide based mixed matrix membranes (MMMs). It is found that MMMs concurrently exhibited higher gas selectivity and higher gas permeability compared to pristine polyimide. The high gas selectivity could be attributed to the GONRs shell, which provided a selective barrier and large gas adsorbed area, while the high gas permeability resulted from the hollow structured MWCNTs core with smooth internal surface, which acted as a rapid transport channel. MWCNT@GONRs could be promising candidates to improve gas separation performance of MMMs due to the unique microstructures, ease of synthesis and low filling loading.

Determination of mutually interfering elements in activation analysis

International Nuclear Information System (INIS)

Figueiredo, A.M.G.

1979-01-01

The determination of the elements present in the groups scandium-zinc, mercury-selenium and arsenic-antimony-bromine represents a classical problem in thermal neutron activation analysis because the gamma-ray peaks of the radioisotopes produced from these elements by activation appear very close in the spectrum. A study is made of the possibility of simultaneous instrumental determination of these elements by means of the spectrum stripping technique, using a 400-channel analyser coupled to a Nal(Tl) detector and a 4096-channel analyser coupled to a Ge(Li) detector. Artificial mixtures of the interfering elements in varying proportions are prepared, so as to reproduce possible real samples, where the elements may be present at several concentrations. Radiochemical separation techniques for the cited elements are studied with the use of tracers. For the separation of scadium and zinc, the technique of extraction chromatography is applied. The separation of mercury and selenium is accomplished by means of ion exchange. The technique of coprecipitation is used to separate bromine from arsenic and antimony followed by ion exchange to isolate these two elements from each other. The precision and the accuracy of the results are discussed. (Author) [pt

Effect of kinetic properties of extraction systems on separation of some elements by liquid chromatography method with free fixed phase

International Nuclear Information System (INIS)

Fedotov, P.S.; Maryutina, T.A.; Pichugin, A.A.; Spivakov, B.Ya.

1993-01-01

Effect of kinetic properties of a series of extraction systems on the separation of certain elements by the method of liquid chromatography with free fixed phase is considered. Chromatographic behaviour of europium 3 and iron 3 ions when using systems based on di-2-ethylhexylphosphovers acid and tetraphenylmethylenediphosphine dioxide is investigated. Kinetic properties of the extraction systems used are studied by diffusion cell method with mixing, europium 3 and iron 3 mass transfer coefficients are determined

Technical feasibility of advanced separation; Faisabilite technique de la separation poussee

Energy Technology Data Exchange (ETDEWEB)

Rostaing, Ch

2004-07-01

Advanced separation aims at reducing the amount and toxicity of high-level and long lived radioactive wastes. The Purex process has been retained as a reference way for the recovery of the most radio-toxic elements: neptunium, technetium and iodine. Complementary solvent extraction processes have to be developed for the separation of americium, curium and cesium from the high activity effluent of the spent fuel reprocessing treatment. Researches have been carried out with the aim of demonstrating the scientifical and technical feasibility of advanced separation of minor actinides and long lived fission products from spent fuels. The scientifical feasibility was demonstrated at the end of 2001. The technical feasibility works started in the beginning of 2002. Many results have been obtained which are presented and summarized in this document: approach followed, processes retained for the technical feasibility (An/Ln and Am/Cm separation), processes retained for further validation at the new shielded Purex installation, technical feasibility of Purex adaptation to Np separation, technical feasibility of Diamex (first step: (An+Ln)/other fission products) separation), technical feasibility of Sanex process (second step: An(III)/Ln(III) separation), technical feasibility of Am(III)/Cm(III) separation, cesium separation, iodine separation, technical-economical evaluation, conclusions and perspectives, facilities and apparatuses used for the experiments. (J.S.)

Isotope separation process

International Nuclear Information System (INIS)

Lyon, R.K.

1977-01-01

The instant invention relates to a process for separating a material into two or more parts in each of which the abundances of the isotopes of a given element differ from the abundances of the isotopes of the same material in said material. More particularly, the invention relates to a method for the isotopically selective excitation of gas phase molecules by multiple infrared photon absorption followed by a step wherein more of the excited molecules than nonexcited molecules are converted to a chemically different form which may be separated by means known in the art. This invention is useful for, but not limited to, the separation of the principal isotopes of uranium. 15 claims, 1 figure

Method of separating hafnium from zirconium

International Nuclear Information System (INIS)

Megy, J.A.

1980-01-01

English. A new anhydrous method was developed for separating zirconium and hafnium, which gives higher separation factors and is more economical than previous methods. A molten phase, comprising a solution of unseparated zirconium and hafnium and a solvent metal, is first prepared. The molten metal phase is contacted with a fused salt phase which includes a zirconium salt. Zirconium and hafnium separation is effected by mutual displacement with hafnium being transported from the molten metal phase to the fused salt phase, while zirconium is transported from the fused salt phase to the molten metal phase. The solvent metal is less electropositive than zirconium. Zinc was chosen as the solvent metal, from a group which also included cadmium, lead, bismuth, copper, and tin. The fused salt phase cations are more electropositive than zirconium and were selected from a group comprising the alkali elements, the alkaline earth elements, the rare earth elements, and aluminum. A portion of the zirconium in the molten metal phase was oxidized by injecting an oxidizing agent, chlorine, to form zirconium tetrachlorid

Multi-element sewer slime impact pattern--a quantitative characteristic enabling identification of the source of heavy metal discharges into sewer systems.

Science.gov (United States)

Kintrup, J; Wünsch, G

2001-11-01

The capability of sewer slime to accumulate heavy metals from municipal wastewater can be exploited to identify the sources of sewage sludge pollution. Former investigations of sewer slime looked for a few elements only and could, therefore, not account for deviations of the enrichment efficiency of the slime or for irregularities from sampling. Results of ICP-MS multi element determinations were analyzed by multivariate statistical methods. A new dimensionless characteristic "sewer slime impact" is proposed, which is zero for unloaded samples. Patterns expressed in this data format specifically extract the information required to identify the type of pollution and polluter quicker and with less effort and cost than hitherto.

Jansen-MIDAS: A multi-level photomicrograph segmentation software based on isotropic undecimated wavelets.

Science.gov (United States)

de Siqueira, Alexandre Fioravante; Cabrera, Flávio Camargo; Nakasuga, Wagner Massayuki; Pagamisse, Aylton; Job, Aldo Eloizo

2018-01-01

Image segmentation, the process of separating the elements within a picture, is frequently used for obtaining information from photomicrographs. Segmentation methods should be used with reservations, since incorrect results can mislead when interpreting regions of interest (ROI). This decreases the success rate of extra procedures. Multi-Level Starlet Segmentation (MLSS) and Multi-Level Starlet Optimal Segmentation (MLSOS) were developed to be an alternative for general segmentation tools. These methods gave rise to Jansen-MIDAS, an open-source software. A scientist can use it to obtain several segmentations of hers/his photomicrographs. It is a reliable alternative to process different types of photomicrographs: previous versions of Jansen-MIDAS were used to segment ROI in photomicrographs of two different materials, with an accuracy superior to 89%. © 2017 Wiley Periodicals, Inc.

Multi-scale damage modelling in a ceramic matrix composite using a finite-element microstructure meshfree methodology

Science.gov (United States)

2016-01-01

The problem of multi-scale modelling of damage development in a SiC ceramic fibre-reinforced SiC matrix ceramic composite tube is addressed, with the objective of demonstrating the ability of the finite-element microstructure meshfree (FEMME) model to introduce important aspects of the microstructure into a larger scale model of the component. These are particularly the location, orientation and geometry of significant porosity and the load-carrying capability and quasi-brittle failure behaviour of the fibre tows. The FEMME model uses finite-element and cellular automata layers, connected by a meshfree layer, to efficiently couple the damage in the microstructure with the strain field at the component level. Comparison is made with experimental observations of damage development in an axially loaded composite tube, studied by X-ray computed tomography and digital volume correlation. Recommendations are made for further development of the model to achieve greater fidelity to the microstructure. This article is part of the themed issue ‘Multiscale modelling of the structural integrity of composite materials’. PMID:27242308

Free and Forced Vibrations of an Axially-Loaded Timoshenko Multi-Span Beam Carrying a Number of Various Concentrated Elements

Directory of Open Access Journals (Sweden)

Yusuf Yesilce

2012-01-01

Full Text Available In the existing reports regarding free and forced vibrations of the beams, most of them studied a uniform beam carrying various concentrated elements using Bernoulli-Euler Beam Theory (BET but without axial force. The purpose of this paper is to utilize the numerical assembly technique to determine the exact frequency-response amplitudes of the axially-loaded Timoshenko multi-span beam carrying a number of various concentrated elements (including point masses, rotary inertias, linear springs and rotational springs and subjected to a harmonic concentrated force and the exact natural frequencies and mode shapes of the beam for the free vibration analysis. The model allows analyzing the influence of the shear and axial force and harmonic concentrated force effects and intermediate concentrated elements on the dynamic behavior of the beams by using Timoshenko Beam Theory (TBT. At first, the coefficient matrices for the intermediate concentrated elements, an intermediate pinned support, applied harmonic force, left-end support and right-end support of Timoshenko beam are derived. After the derivation of the coefficient matrices, the numerical assembly technique is used to establish the overall coefficient matrix for the whole vibrating system. Finally, solving the equations associated with the last overall coefficient matrix one determines the exact dynamic response amplitudes of the forced vibrating system corresponding to each specified exciting frequency of the harmonic force. Equating the determinant of the overall coefficient matrix to zero one determines the natural frequencies of the free vibrating system (the case of zero harmonic force and substituting the corresponding values of integration constants into the related eigenfunctions one determines the associated mode shapes. The calculated vibration amplitudes of the forced vibrating systems and the natural frequencies of the free vibrating systems are given in tables for different values of

Application of a particle separation device to reduce inductively coupled plasma-enhanced elemental fractionation in laser ablation-inductively coupled plasma-mass spectrometry

International Nuclear Information System (INIS)

Guillong, Marcel; Kuhn, Hans-Rudolf; Guenther, Detlef

2003-01-01

The particle size distribution of laser ablation aerosols are a function of the wavelength, the energy density and the pulse duration of the laser, as well as the sample matrix and the gas environment. Further the size of the particles affects the vaporization and ionization efficiency in the inductively coupled plasma (ICP). Some matrices produce large particles, which are not completely vaporized and ionized in the ICP. The previous work has shown that analytical results such as matrix-independent calibration, accuracy and precision can be significantly influenced by the particle sizes of the particles. To minimize the particle size related incomplete conversion of the sample to ions in the ICP a particle separation device was developed, which allows effective particle separation using centrifugal forces in a thin coiled tube. In this device, the particle cut-off size is varied by changing the number of turns in the coil, as well as by changing the gas flow and the tube diameter. The interaction of the laser with the different samples leads to varying particle size distributions. When carrying out quantitative analysis with non-matrix matched calibration reference materials, it was shown that different particle cut-off sizes were required depending on the ICP conditions and the instrument used for analysis. Various sample materials were investigated in this study to demonstrate the applicability of the device. For silicate matrices, the capability of the ICP to produce ions was significantly reduced for particles larger than 0.5 μm, and was dependent on the element monitored. To reduce memory effects caused by the separated particles, a washout procedure was developed, which additionally allowed the analysis of the trapped particles. These results clearly demonstrate the very important particle size dependent ICP-MS signal response and the potential of the described particle size based separator for the reduction of ICP induced elemental fractionation

Isotope separation process

International Nuclear Information System (INIS)

1976-01-01

The invention relates to a process for separating a given material into two or more parts, in each of which the abundances of the isotopes of a given element differ from the abundances of the isotopes of the same material in the said material. More particularly, the invention relates to a method for the isotopically selective excitation of gas phase UF 6 by infrared photon absorption followed by selective reaction of said excited UF 6 with atomic chlorine, bromine, or iodine to form a product which may be separated by means known in the art

Application of PCA-LDA method to determine the geographical origin of tea based on determination of stable isotopes and multi-elements

International Nuclear Information System (INIS)

Yuan Yuwei; Zhang Yongzhi; Yang Guiling; Zhang Zhiheng; Fu Haiyan; Han Wenyan; Li Shufang

2013-01-01

The ratio of stable isotope and concentration of multi-element in tea was determinated with isotope ratio mass spectrometry (IRMS) and inductively coupled plasma mass spectrometry (ICP-MS). Pattern recognition techniques with principal component analysis (PCA) and linear discriminant analysis (LDA) were used to classify the geographical origins of tea from Fujian, Shandong and Zhejiang province, and Yuyao, Jinhua and Xihu region of Zhejiang. The results showed the values of δ"1"5N, δ"1"3C, δD, δ"1"8O and the ratios of "2"0"6Pb/"2"0"7Pb, "2"0"8Pb/"2"0"6Pb and "8"7Sr/"8"6Sr in tea samples were different from different origins. There was also large variable for the concentrations of 27 mineral elements, such as Li, Be, Na and so on, with a specific character of origin. The method of PCA could be used to classify the geographical origin of tea from different origins but with a cross in the scatter plot. However, PCA combining with LDA could gave correct assignation percentages of 99% for the tea samples among Fujian, Shandong and Zhejiang provinces, and 87% for the tea samples among Yuyao, Jinhua and Xihu region of Zhejiang. These results revealed that it was possible and feasible to classify the geographical origin of tea by the method of PCA-LDA based on the determination of isotopes and multi-elements. (authors)

Undergraduate Student Peer Mentoring in a Multi-Faculty, Multi-Campus University Context

Science.gov (United States)

Townsend, Robert A.; Delves, Melinda; Kidd, Tracy; Figg, Bev

2011-01-01

This article explores research that utilised a mapping strategy to investigate the elements of peer mentoring and peer tutoring programs across a multi-campus Australian university. Peer mentoring, peer tutoring and peer learning activities at the multi-campus university are occurring in a manner that may be considered ad-hoc which does not…

Modelling of the acoustic field of a multi-element HIFU array scattered by human ribs

Science.gov (United States)

Gélat, Pierre; ter Haar, Gail; Saffari, Nader

2011-09-01

The efficacy of high-intensity focused ultrasound (HIFU) for the treatment of a range of different cancers, including those of the liver, prostate and breast, has been demonstrated. As a non-invasive focused therapy, HIFU offers considerable advantages over techniques such as chemotherapy and surgical resection in terms of reduced risk of harmful side effects. Despite this, there are a number of significant challenges which currently hinder its widespread clinical application. One of these challenges is the need to transmit sufficient energy through the rib cage to induce tissue necrosis in the required volume whilst minimizing the formation of side lobes. Multi-element random-phased arrays are currently showing great promise in overcoming the limitations of single-element transducers. Nevertheless, successful treatment of a patient with liver tumours requires a thorough understanding of the way in which the ultrasonic pressure field from a HIFU array is scattered by the rib cage. In order to address this, a boundary element approach based on a generalized minimal residual (GMRES) implementation of the Burton-Miller formulation was used in conjunction with phase conjugation techniques to focus the field of a 256-element random HIFU array behind human ribs at locations requiring intercostal and transcostal treatment. Simulations were carried out on a 3D mesh of quadratic pressure patches generated using CT scan anatomical data for adult ribs 9-12 on the right side. The methodology was validated on spherical and cylindrical scatterers. Field calculations were also carried out for idealized ribs, consisting of arrays of strip-like scatterers, demonstrating effects of splitting at the focus. This method has the advantage of fully accounting for the effect of scattering and diffraction in 3D under continuous wave excitation.

Modelling of the acoustic field of a multi-element HIFU array scattered by human ribs

Energy Technology Data Exchange (ETDEWEB)

Gelat, Pierre [National Physical Laboratory, Hampton Road, Teddington TW11 0LW (United Kingdom); Ter Haar, Gail [Therapeutic Ultrasound Group, Physics Department, Institute of Cancer Research, Sutton SM2 5NG (United Kingdom); Saffari, Nader, E-mail: Pierre.Gelat@npl.co.uk [Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom)

2011-09-07

The efficacy of high-intensity focused ultrasound (HIFU) for the treatment of a range of different cancers, including those of the liver, prostate and breast, has been demonstrated. As a non-invasive focused therapy, HIFU offers considerable advantages over techniques such as chemotherapy and surgical resection in terms of reduced risk of harmful side effects. Despite this, there are a number of significant challenges which currently hinder its widespread clinical application. One of these challenges is the need to transmit sufficient energy through the rib cage to induce tissue necrosis in the required volume whilst minimizing the formation of side lobes. Multi-element random-phased arrays are currently showing great promise in overcoming the limitations of single-element transducers. Nevertheless, successful treatment of a patient with liver tumours requires a thorough understanding of the way in which the ultrasonic pressure field from a HIFU array is scattered by the rib cage. In order to address this, a boundary element approach based on a generalized minimal residual (GMRES) implementation of the Burton-Miller formulation was used in conjunction with phase conjugation techniques to focus the field of a 256-element random HIFU array behind human ribs at locations requiring intercostal and transcostal treatment. Simulations were carried out on a 3D mesh of quadratic pressure patches generated using CT scan anatomical data for adult ribs 9-12 on the right side. The methodology was validated on spherical and cylindrical scatterers. Field calculations were also carried out for idealized ribs, consisting of arrays of strip-like scatterers, demonstrating effects of splitting at the focus. This method has the advantage of fully accounting for the effect of scattering and diffraction in 3D under continuous wave excitation.

Pyrometallurgical partitioning of uranium and transuranic elements from rare earth elements by electrorefining and reductive extraction

International Nuclear Information System (INIS)

Uozumi, Koichi; Kinoshita, Kensuke; Inoue, Tadashi; Storvick, T.S.; Krueger, C.L.; Nabelek, C.R.

2001-01-01

High-level liquid waste generated from PUREX reprocessing contains a small amount of transuranic elements, such as Np, Pu, Am, and Cm, with long-lived radioactivities. A pyrometallurgical partitioning process is being developed to recover transuranic elements from such waste. Small amounts of U contained in the high-level liquid waste are also recovered in the process. A key issue for developing the process is effective separation of U and the transuranic elements from the rare-earth elements, because the two elemental groups are chemically analogous. A series of process tests were carried out in the present study to demonstrate that a combination of electrorefining and reductive extraction is useful for separating U and transuranic elements from the rare-earth elements. The results indicate that 99% of U and each transuranic elements is recovered by the combination process as a product, and that the quantity of rare-earth elements contained in the product is smaller than the transuranic elements by weight. The overall mass balance of U and transuranic elements in the system ranged within the experimental errors assigned to sampling and analysis. (author)

Analysis and synthesis of multi-qubit, multi-mode quantum devices

Energy Technology Data Exchange (ETDEWEB)

Solgun, Firat

2015-03-27

In this thesis we propose new methods in multi-qubit multi-mode circuit quantum electrodynamics (circuit-QED) architectures. First we describe a direct parity measurement method for three qubits, which can be realized in 2D circuit-QED with a possible extension to four qubits in a 3D circuit-QED setup for the implementation of the surface code. In Chapter 3 we show how to derive Hamiltonians and compute relaxation rates of the multi-mode superconducting microwave circuits consisting of single Josephson junctions using an exact impedance synthesis technique (the Brune synthesis) and applying previous formalisms for lumped element circuit quantization. In the rest of the thesis we extend our method to multi-junction (multi-qubit) multi-mode circuits through the use of state-space descriptions which allows us to quantize any multiport microwave superconducting circuit with a reciprocal lossy impedance response.

A Multi-Element Approach to Location Inference of Twitter: A Case for Emergency Response

Directory of Open Access Journals (Sweden)

Farhad Laylavi

2016-04-01

Full Text Available Since its inception, Twitter has played a major role in real-world events—especially in the aftermath of disasters and catastrophic incidents, and has been increasingly becoming the first point of contact for users wishing to provide or seek information about such situations. The use of Twitter in emergency response and disaster management opens up avenues of research concerning different aspects of Twitter data quality, usefulness and credibility. A real challenge that has attracted substantial attention in the Twitter research community exists in the location inference of twitter data. Considering that less than 2% of tweets are geotagged, finding location inference methods that can go beyond the geotagging capability is undoubtedly the priority research area. This is especially true in terms of emergency response, where spatial aspects of information play an important role. This paper introduces a multi-elemental location inference method that puts the geotagging aside and tries to predict the location of tweets by exploiting the other inherently attached data elements. In this regard, textual content, users’ profile location and place labelling, as the main location-related elements, are taken into account. Location-name classes in three granularity levels are defined and employed to look up the location references from the location-associated elements. The inferred location of the finest granular level is assigned to a tweet, based on a novel location assignment rule. The location assigned by the location inference process is considered to be the inferred location of a tweet, and is compared with the geotagged coordinates as the ground truth of the study. The results show that this method is able to successfully infer the location of 87% of the tweets at the average distance error of 12.2 km and the median distance error of 4.5 km, which is a significant improvement compared with that of the current methods that can predict the location

[Multi-parent families as "normal" families--segregation and parent-child-alienation after separation and divorce].

Science.gov (United States)

Napp-Peters, Anneke

2005-12-01

Decisive for the question as to how children cope with their parents' divorce is whether or not the parents continue to perform their parental role together even after separation, or have at least made arrangements for the child to maintain a good relationship with each parent. These are the findings of a longitudinal study of 150 postdivorce families. The case of a multi-parent family after remarriage, which sees itself as a "normal" family and segregates the visiting parent, shows what consequences the breakdown of parent-child relationships has for the psychological health and the development of children. Alienation and long-term disruption of the contact between child and visiting parent is a phenomenon which the psychiatric and psychotherapeutic professions are increasingly confronted with. The American child psychiatrist R. A. Gardner has introduced the term "Parental Alienation Syndrome (PAS)" to encompass this childhood disorder that arises almost exclusively in the context of child-custody disputes.

Application of dot matrix LCD in multi-element portable X-ray fluorescence spectrometry The LCD is stated for Liquid Crystal Display

CERN Document Server

Lin Yan Chang; Lai Wan Chang; Zhou Si Chun

2002-01-01

Dot matrix LCD based on T6963C is a low power supply module. It needs no complex interface circuits connecting with MCU. Application in text and graphics is easy. Application of this LCD in multi-element portable XRF spectrometry is show. How to use it in Chinese, pull-down menu, spectrum and how to design the interface circuits with embedded computer are shown as well

Computer Aided Design and Analysis of Separation Processes with Electrolyte Systems

DEFF Research Database (Denmark)

A methodology for computer aided design and analysis of separation processes involving electrolyte systems is presented. The methodology consists of three main parts. The thermodynamic part "creates" the problem specific property model package, which is a collection of pure component and mixture...... property models. The design and analysis part generates process (flowsheet) alternatives, evaluates/analyses feasibility of separation and provides a visual operation path for the desired separation. The simulation part consists of a simulation/calculation engine that allows the screening and validation...... of process alternatives. For the simulation part, a general multi-purpose, multi-phase separation model has been developed and integrated to an existing computer aided system. Application of the design and analysis methodology is highlighted through two illustrative case studies....

Computer Aided Design and Analysis of Separation Processes with Electrolyte Systems

DEFF Research Database (Denmark)

Takano, Kiyoteru; Gani, Rafiqul; Kolar, P.

2000-01-01

A methodology for computer aided design and analysis of separation processes involving electrolyte systems is presented. The methodology consists of three main parts. The thermodynamic part 'creates' the problem specific property model package, which is a collection of pure component and mixture...... property models. The design and analysis part generates process (flowsheet) alternatives, evaluates/analyses feasibility of separation and provides a visual operation path for the desired separation. The simulation part consists of a simulation/calculation engine that allows the screening and validation...... of process alternatives. For the simulation part, a general multi-purpose, multi-phase separation model has been developed and integrated to an existing computer aided system. Application of the design and analysis methodology is highlighted through two illustrative case studies, (C) 2000 Elsevier Science...

Stress analysis of disconnected structures in contact through finite element gaps

International Nuclear Information System (INIS)

Stadter, J.T.; Weiss, R.O.

1976-07-01

A numerical procedure is presented for analyzing thermal stress problems of disconnected structures in contact across separations or gaps. The new procedure is called SAASGAPS, an adaptation of the basic SAAS III computer program. The SAAS program uses the finite element method and allows analyses of plane and axisymmetric bodies with temperature dependent material properties, subject to thermal and mechanical loads. A secant modulus approach with a bilinear stress-strain curve is used for elastic-plastic problems. The SAASGAPS version contains all of the features of the original SAAS program. A special gap element is used together with a stress invariance principle to model the contact process. The iterative procedure implemented in SAASGAPS is described. Results are discussed for five problems involving frictionless contact. Two of these problems are associated with the thermal stress analysis of the heat shield for the Multi-Hundred Watt Radioisotope Thermoelectric Generator. Input instructions for the program are described in an appendix

Experimental validation of a multi-energy x-ray adapted scatter separation method

Science.gov (United States)

Sossin, A.; Rebuffel, V.; Tabary, J.; Létang, J. M.; Freud, N.; Verger, L.

2016-12-01

Both in radiography and computed tomography (CT), recently emerged energy-resolved x-ray photon counting detectors enable the identification and quantification of individual materials comprising the inspected object. However, the approaches used for these operations require highly accurate x-ray images. The accuracy of the images is severely compromised by the presence of scattered radiation, which leads to a loss of spatial contrast and, more importantly, a bias in radiographic material imaging and artefacts in CT. The aim of the present study was to experimentally evaluate a recently introduced partial attenuation spectral scatter separation approach (PASSSA) adapted for multi-energy imaging. For this purpose, a prototype x-ray system was used. Several radiographic acquisitions of an anthropomorphic thorax phantom were performed. Reference primary images were obtained via the beam-stop (BS) approach. The attenuation images acquired from PASSSA-corrected data showed a substantial increase in local contrast and internal structure contour visibility when compared to uncorrected images. A substantial reduction of scatter induced bias was also achieved. Quantitatively, the developed method proved to be in relatively good agreement with the BS data. The application of the proposed scatter correction technique lowered the initial normalized root-mean-square error (NRMSE) of 45% between the uncorrected total and the reference primary spectral images by a factor of 9, thus reducing it to around 5%.

Magnetic particle separation using controllable magnetic force switches

International Nuclear Information System (INIS)

Wei Zunghang; Lee, C.-P.; Lai, M.-F.

2010-01-01

Magnetic particle separation is very important in biomedical applications. In this study, a magnetic particle microseparator is proposed that uses micro magnets to produce open/closed magnetic flux for switching on/off the separation. When all magnets are magnetized in the same direction, the magnetic force switch for separation is on; almost all magnetic particles are trapped in the channel side walls and the separation rate can reach 95%. When the magnetization directions of adjacent magnets are opposite, the magnetic force switch for separation is off, and most magnetic particles pass through the microchannel without being trapped. For the separation of multi-sized magnetic particles, the proposed microseparator is numerically demonstrated to have high separation rate.

Design and Fabrication of Oxygen/RP-2 Multi-Element Oxidizer-Rich Staged Combustion Thrust Chamber Injectors

Science.gov (United States)

Garcia, C. P.; Medina, C. R.; Protz, C. S.; Kenny, R. J.; Kelly, G. W.; Casiano, M. J.; Hulka, J. R.; Richardson, B. R.

2016-01-01

As part of the Combustion Stability Tool Development project funded by the Air Force Space and Missile Systems Center, the NASA Marshall Space Flight Center was contracted to assemble and hot-fire test a multi-element integrated test article demonstrating combustion characteristics of an oxygen/hydrocarbon propellant oxidizer-rich staged-combustion engine thrust chamber. Such a test article simulates flow through the main injectors of oxygen/kerosene oxidizer-rich staged combustion engines such as the Russian RD-180 or NK-33 engines, or future U.S.-built engine systems such as the Aerojet-Rocketdyne AR-1 engine or the Hydrocarbon Boost program demonstration engine. On the current project, several configurations of new main injectors were considered for the thrust chamber assembly of the integrated test article. All the injector elements were of the gas-centered swirl coaxial type, similar to those used on the Russian oxidizer-rich staged-combustion rocket engines. In such elements, oxidizer-rich combustion products from the preburner/turbine exhaust flow through a straight tube, and fuel exiting from the combustion chamber and nozzle regenerative cooling circuits is injected near the exit of the oxidizer tube through tangentially oriented orifices that impart a swirl motion such that the fuel flows along the wall of the oxidizer tube in a thin film. In some elements there is an orifice at the inlet to the oxidizer tube, and in some elements there is a sleeve or "shield" inside the oxidizer tube where the fuel enters. In the current project, several variations of element geometries were created, including element size (i.e., number of elements or pattern density), the distance from the exit of the sleeve to the injector face, the width of the gap between the oxidizer tube inner wall and the outer wall of the sleeve, and excluding the sleeve entirely. This paper discusses the design rationale for each of these element variations, including hydraulic, structural

A finite element method based microwave heat transfer modeling of frozen multi-component foods

Science.gov (United States)

Pitchai, Krishnamoorthy

Microwave heating is fast and convenient, but is highly non-uniform. Non-uniform heating in microwave cooking affects not only food quality but also food safety. Most food industries develop microwavable food products based on "cook-and-look" approach. This approach is time-consuming, labor intensive and expensive and may not result in optimal food product design that assures food safety and quality. Design of microwavable food can be realized through a simulation model which describes the physical mechanisms of microwave heating in mathematical expressions. The objective of this study was to develop a microwave heat transfer model to predict spatial and temporal profiles of various heterogeneous foods such as multi-component meal (chicken nuggets and mashed potato), multi-component and multi-layered meal (lasagna), and multi-layered food with active packages (pizza) during microwave heating. A microwave heat transfer model was developed by solving electromagnetic and heat transfer equations using finite element method in commercially available COMSOL Multiphysics v4.4 software. The microwave heat transfer model included detailed geometry of the cavity, phase change, and rotation of the food on the turntable. The predicted spatial surface temperature patterns and temporal profiles were validated against the experimental temperature profiles obtained using a thermal imaging camera and fiber-optic sensors. The predicted spatial surface temperature profile of different multi-component foods was in good agreement with the corresponding experimental profiles in terms of hot and cold spot patterns. The root mean square error values of temporal profiles ranged from 5.8 °C to 26.2 °C in chicken nuggets as compared 4.3 °C to 4.7 °C in mashed potatoes. In frozen lasagna, root mean square error values at six locations ranged from 6.6 °C to 20.0 °C for 6 min of heating. A microwave heat transfer model was developed to include susceptor assisted microwave heating of a

Amalgam-chromatographic separation of magnesium isotopes

International Nuclear Information System (INIS)

Klinskij, G.D.; Levkin, A.V.; Ivanov, S.A.

1990-01-01

Separation of magnesium isotopes within Mg(Hg)-MgI 2 system (in dimethylformamide) is conducted under amalgam-chromatographic conditions. Separation maximal degree, that is (1.09), for 24 Mg and 26 Mg and separation coefficient (α = 1.0089±0.006) are determined. Light isotopes are found to concentrate in the amalgam. Technique of thermal conversion of flows within amalgam-dimethylformamide system is suggested on the basis of reversible reaction of Ca-Mg element exchange

A positive and multi-element conserving time stepping scheme for biogeochemical processes in marine ecosystem models

Science.gov (United States)

Radtke, H.; Burchard, H.

2015-01-01

In this paper, an unconditionally positive and multi-element conserving time stepping scheme for systems of non-linearly coupled ODE's is presented. These systems of ODE's are used to describe biogeochemical transformation processes in marine ecosystem models. The numerical scheme is a positive-definite modification of the Runge-Kutta method, it can have arbitrarily high order of accuracy and does not require time step adaption. If the scheme is combined with a modified Patankar-Runge-Kutta method from Burchard et al. (2003), it also gets the ability to solve a certain class of stiff numerical problems, but the accuracy is restricted to second-order then. The performance of the new scheme on two test case problems is shown.

Multi-element sewer slime impact pattern - a quantitative characteristic enabling identification of the source of heavy metal discharges into sewer systems

Energy Technology Data Exchange (ETDEWEB)

Kintrup, J. [Chemistry Lab., Wessling GmbH, Hannover (Germany); Wuensch, G. [Lehrgebiet Analytische Chemie, Univ. Hannover (Germany)

2001-11-01

The capability of sewer slime to accumulate heavy metals from municipal wastewater can be exploited to identify the sources of sewage sludge pollution. Former investigations of sewer slime looked for a few elements only and could, therefore, not account for deviations of the enrichment efficiency of the slime or for irregularities from sampling. Results of ICP-MS multi element determinations were analyzed by multivariate statistical methods. A new dimensionless characteristic ''sewer slime impact'' is proposed, which is zero for unloaded samples. Patterns expressed in this data format specifically extract the information required to identify the type of pollution and polluter quicker and with less effort and cost than hitherto. (orig.)

ICP-AES determination of trace elements in carbon steel

International Nuclear Information System (INIS)

Sengupta, Arijit; Rajeswari, B.; Kadam, R.M.; Babu, Y.; Godbole, S.V.

2010-01-01

Full text: Carbon steel, a combination of the elements iron and carbon, can be classified into four types as mild, medium, high and very high depending on the carbon content which varies from 0.05% to 2.1%. Carbon steel of different types finds application in medical devices, razor blades, cutlery and spring. In the nuclear industry, it is used in feeder pipes in the reactor. A strict quality control measure is required to monitor the trace elements, which have deleterious effects on the mechanical properties of the carbon steel. Thus, it becomes imperative to check the purity of carbon steel as a quality control measure before it is used in feeder pipes in the reactor. Several methods have been reported in literature for trace elemental determination in high purity iron. Some of these include neutron activation analysis, atomic absorption spectrometry and atomic emission spectrometry. Inductively coupled plasma atomic emission spectrometry (ICP-AES) is widely recognized as a sensitive technique for the determination of trace elements in various matrices, its major advantages being good accuracy and precision, high sensitivity, multi-element capability, large linear dynamic range and relative freedom from matrix effects. The present study mainly deals with the direct determination of trace elements in carbon steel using ICP-AES. An axially viewing ICP spectrometer having a polychromator with 35 fixed analytical channels and limited sequential facility to select any analytical line within 2.2 nm of a polychromator line was used in these studies. Iron, which forms one of the main constituents of carbon steel, has a multi electronic configuration with line rich emission spectrum and, therefore, tends to interfere in the determination of trace impurities in carbon steel matrix. Spectral interference in ICP-AES can be seriously detrimental to the accuracy and reliability of trace element determinations, particularly when they are performed in the presence of high

Wear And Tear Determination By Trace Multi-Element Analysis Of An Unused And Used Lubricant Oil Using Instrumental Neutron Activation Analysis

International Nuclear Information System (INIS)

Adeyemo, D.J.

2004-01-01

Instrumental neutron activation analysis technique using the Imperial College Centre consort M. K. II nuclear reactor was utilized for the determination of: As, Ba Ca CI, Co, Cr, Cu, Fe, K, Mn, Mo, Na Ni, Rb, Sb, Se, Ti, V, and Zn, in an imported and used car lubricant oil. The wear of the oil lubricated parts of the car engine was monitored by establishing a correlation between the results obtained in the analysis. The result obtained from the analysis of the unused and then used samples on a low performing oil leaking four stroke car engine showed an increase on all the elements determined except for Se and Rb. The precision for the multi-element analysis is less than 12% for most of the elements. The accuracy of the measurement is also validated by the result obtained from the analysis of NBS-SRM1635 (sub-bituminous) coal standard for the elements. The results obtained indicate that analysis of unused and used lubricant oil samples can aid in locating defects in engine parts and hence facilitated maintenance procedures

Electrochemical performance of multi-element doped α-nickel hydroxide prepared by supersonic co-precipitation method

International Nuclear Information System (INIS)

Zhang, Z.J.; Zhu, Y.J.; Bao, J.; Lin, X.R.; Zheng, H.Z.

2011-01-01

Highlights: → The α-nickel hydroxides doped with several elements were prepared by supersonic co-precipitation method. → Cyclic voltammetry and electrochemical impedance spectroscopy show sample C has the best electrochemical performance. → The charge/discharge tests show that the 0.5 C discharge capacity (346 mAh/g) of sample C is even larger than that (337 mAh/g) at 0.1 C rate, while the discharge capacity at 0.5 C rate is much lower than that at 0.1 C rate for samples A and B. - Abstract: The multi-element doped α-nickel hydroxides have been prepared by supersonic co-precipitation method. Three kinds of samples A, B, C were prepared by chemically coprecipitating Ni, Al, Co, Y, Zn. It was found that sample C produced better performance than the others. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements indicated that sample C has better electrochemical performance, such as better reaction reversibility, higher proton diffusion coefficient and lower charge-transfer resistance, than those of samples A and B. The charge-discharge tests showed that the discharge capacity (346 mA h/g) of sample C is even larger at 0.5 C rate than that (337mAh/g) at 0.1 C rate, while the discharge capacity at 0.5 C rate is much lower than that at 0.1 C rate for samples A and B. It indicates that all doped elements can produce the synergic effect and further improve the electrochemical properties of the active materials.

Magnetic separation in microfluidic systems

DEFF Research Database (Denmark)

Smistrup, Kristian

2007-01-01

to facilitate real-time monitoring of the experiments. The set-up and experimental protocol are described in detail. Results are presented for ’active’ magnetic bead separators, where on-chip microfabricated electromagnets supply the magnetic field and field gradients necessary for magnetic bead separation....... It is shown conceptually how such a system can be applied for parallel biochemical processing in a microfluidic system. ’Passive’ magnetic separators are presented, where on-chip soft magnetic elements are magnetized by an external magnetic field and create strong magnetic fields and gradients inside...

Chemical analysis of rare earth elements

International Nuclear Information System (INIS)

Tsukahara, Ryoichi; Sakoh, Takefumi; Nagai, Iwao

1994-01-01

Recently attention has been paid to ICP-AES or ICP-MS, and the reports on the analysis of rare earth elements by utilizing these methods continue to increase. These reports have become to take about 30% of the reports on rare earth analysis, and this is because these methods are highly sensitive to rare earth elements, and also these methods have spread widely. In ICP-AES and ICP-MS, mostly solution samples are measured, therefore, solids must be made into solution. At the time of quantitatively determining the rare earth elements of low concentration, separation and concentration are necessary. Referring to the literatures reported partially in 1990 and from 1991 to 1993, the progress of ICP-AES and ICP-MS is reported. Rare earth oxides and the alloys containing rare earth elements are easily decomposed with acids, but the decomposition of rocks is difficult, and its method is discussed. The separation of the rare earth elements from others in geochemical samples, cation exchange process is frequently utilized. Also solvent extraction process has been studied. For the separation of rare earth elements mutually, chromatography is used. The spectral interference in spectral analysis was studied. The comparison of these methods with other methods is reported. (K.I)

Multi-trace elements level in drinking water and the prevalence of multi-chronic arsenical poisoning in residents in the west area of Iran

Energy Technology Data Exchange (ETDEWEB)

Barati, A.H., E-mail: ah_barati@yahoo.com [Department of Medical Physics, Faculty of Medicine, Kurdistan University of Medical Sciences, P.O.Box-66135-756, Pasdaran Street, Sanandaj (Iran, Islamic Republic of); Maleki, A. [Department of Environmental Health, Faculty of Health Sciences, Kurdistan University of Medical Sciences, Sanandaj (Iran, Islamic Republic of); Alasvand, M. [Department of Medical Physiology, Faculty of Medicine, Kurdistan University of Medical Sciences, Sanandaj (Iran, Islamic Republic of)

2010-03-01

First, we determined the levels of 8 trace elements (As, Se, Hg, Cd, Ag, Mn, Cr and Pb) in 530 village drinking water sources by graphite furnace or flame atomic absorption spectroscopy method, in Kurdistan Province in the west of Iran. The results showed that the level of As, Cd and Se in 28 village drinking water sources exceeded WHO or National Standard limits. The levels of concentration of arsenic in drinking water ranged from 42 to 1500 {mu}g/L. Then in a cross-sectional survey, 587 people from 211 households were chosen for clinical examinations of multi-chronic arsenical poisoning including pigment disorders, keratosis of palms and soles, Mee's line in fingers and nails and the gangrene as a systemic manifestation. Of 587 participants, 180 (30.7%) participants were affected by representing the type of chronic arsenical poisoning. The prevalence of Mee's line, keratosis, and pigment disorders were 86.1%, 77.2% and 67.8% respectively. Therefore, the prevalence of Mee's line between inhabitants was higher than the other disorders. The results show a strong linear relationship between arsenic exposure and occurrence of multi-chronic arsenical poisoning (R{sup 2} = 0.76). The association between age for more than 40 years and gender for more than 60 years with chronic arsenical poisoning is significant (p < 0.05). Also, there is a relationship between subjects who were affected with disorders and duration of living in the village. Except for gangrene disorder, the odds ratio of prevalence of other disorders with arsenic exposure level in drinking water show a highly significant relationship between arsenic content and the risk of chronic disorders (p < 0.01). These results confirm the need to further study trace elements in drinking waters, food products and other samples in this area and the relationship to other chronic diseases arising out of arsenicosis.

Multi-Column Experimental Test Bed Using CaSDB MOF for Xe/Kr Separation

Energy Technology Data Exchange (ETDEWEB)

Welty, Amy Keil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Greenhalgh, Mitchell Randy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Garn, Troy Gerry [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-03-01

Processing of spent nuclear fuel produces off-gas from which several volatile radioactive components must be separated for further treatment or storage. As part of the Off-gas Sigma Team, parallel research at INL and PNNL has produced several promising sorbents for the selective capture of xenon and krypton from these off-gas streams. In order to design full-scale treatment systems, sorbents that are promising on a laboratory scale must be proven under process conditions to be considered for pilot and then full-scale use. To that end, a bench-scale multi-column system with capability to test multiple sorbents was designed and constructed at INL. This report details bench-scale testing of CaSDB MOF, produced at PNNL, and compares the results to those reported last year using INL engineered sorbents. Two multi-column tests were performed with the CaSDB MOF installed in the first column, followed with HZ-PAN installed in the second column. The CaSDB MOF column was placed in a Stirling cryocooler while the cryostat was employed for the HZ-PAN column. Test temperatures of 253 K and 191 K were selected for the first column while the second column was held at 191 K for both tests. Calibrated volume sample bombs were utilized for gas stream analyses. At the conclusion of each test, samples were collected from each column and analyzed for gas composition. While CaSDB MOF does appear to have good capacity for Xe, the short time to initial breakthrough would make design of a continuous adsorption/desorption cycle difficult, requiring either very large columns or a large number of smaller columns. Because of the tenacity with which Xe and Kr adhere to the material once adsorbed, this CaSDB MOF may be more suitable for use as a long-term storage solution. Further testing is recommended to determine if CaSDB MOF is suitable for this purpose.

Computational Analysis of Multi-Rotor Flows

Science.gov (United States)

Yoon, Seokkwan; Lee, Henry C.; Pulliam, Thomas H.

2016-01-01

Interactional aerodynamics of multi-rotor flows has been studied for a quadcopter representing a generic quad tilt-rotor aircraft in hover. The objective of the present study is to investigate the effects of the separation distances between rotors, and also fuselage and wings on the performance and efficiency of multirotor systems. Three-dimensional unsteady Navier-Stokes equations are solved using a spatially 5th order accurate scheme, dual-time stepping, and the Detached Eddy Simulation turbulence model. The results show that the separation distances as well as the wings have significant effects on the vertical forces of quadroror systems in hover. Understanding interactions in multi-rotor flows would help improve the design of next generation multi-rotor drones.

Gas separation membranes

Science.gov (United States)

Schell, William J.

1979-01-01

A dry, fabric supported, polymeric gas separation membrane, such as cellulose acetate, is prepared by casting a solution of the polymer onto a shrinkable fabric preferably formed of synthetic polymers such as polyester or polyamide filaments before washing, stretching or calendering (so called griege goods). The supported membrane is then subjected to gelling, annealing, and drying by solvent exchange. During the processing steps, both the fabric support and the membrane shrink a preselected, controlled amount which prevents curling, wrinkling or cracking of the membrane in flat form or when spirally wound into a gas separation element.

FY09 PROGRESS: MULTI-ISOTOPE PROCESS (MIP) MONITOR

International Nuclear Information System (INIS)

Schwantes, Jon M.; Orton, Christopher R.; Fraga, Carlos G.; Christensen, Richard; Laspe, Amy R.; Ward, Rebecca M.

2009-01-01

Model and experimental estimates of the Multi-Isotope Process Monitor performance for determining burnup after dissolution and acid concentration during solvent extraction steps during reprocessing of spent nuclear fuel are presented. Modern industrial reprocessing techniques, including the PUREX and UREX+ family of separations technologies, are based on solvent extraction between organic and aqueous phases. In these bi-phase systems, product (actinide) and contaminant (fission and activation products) elements are preferentially driven (thermodynamically) to opposite phases, with small amounts of each remaining in the other phase. The distribution of each element, between the organic and aqueous phases, is determined by major process variables such as acid concentration, organic ligand concentration, reduction potential, and temperature. Hence, for consistent performance of the separation process, the distribution of each element between the organic and aqueous phases should be relatively constant. During 'normal' operations the pattern of elements distributing into the product and waste streams at each segment of the facility should be reproducible, resulting in a statistically significant signature of the nominal process conditions. Under 'abnormal' conditions, such as those expected under some protracted diversion scenarios, patterns of elements within the various streams would be expected to change measurably. The MIP monitoring approach utilizes changes in the concentrations of gamma-emitting elements as evidence of changes to the process chemistry. It exploits a suite of gamma emitting isotopes to track multiple chemical species and behaviors simultaneously, thus encompassing a large array of elements that are affected by chemical and physical changes. In-process surveillance by the MIP monitor is accomplished by coupling the gamma spectrometry of the streams with multivariate techniques, such as Principal Component Analysis (PCA). PCA is a chemometrics tool

Individual-specific multi-scale finite element simulation of cortical bone of human proximal femur

International Nuclear Information System (INIS)

Ascenzi, Maria-Grazia; Kawas, Neal P.; Lutz, Andre; Kardas, Dieter; Nackenhorst, Udo; Keyak, Joyce H.

2013-01-01

We present an innovative method to perform multi-scale finite element analyses of the cortical component of the femur using the individual’s (1) computed tomography scan; and (2) a bone specimen obtained in conjunction with orthopedic surgery. The method enables study of micro-structural characteristics regulating strains and stresses under physiological loading conditions. The analysis of the micro-structural scenarios that cause variation of strain and stress is the first step in understanding the elevated strains and stresses in bone tissue, which are indicative of higher likelihood of micro-crack formation in bone, implicated in consequent remodeling or macroscopic bone fracture. Evidence that micro-structure varies with clinical history and contributes in significant, but poorly understood, ways to bone function, motivates the method’s development, as does need for software tools to investigate relationships between macroscopic loading and micro-structure. Three applications – varying region of interest, bone mineral density, and orientation of collagen type I, illustrate the method. We show, in comparison between physiological loading and simple compression of a patient’s femur, that strains computed at the multi-scale model’s micro-level: (i) differ; and (ii) depend on local collagen-apatite orientation and degree of calcification. Our findings confirm the strain concentration role of osteocyte lacunae, important for mechano-transduction. We hypothesize occurrence of micro-crack formation, leading either to remodeling or macroscopic fracture, when the computed strains exceed the elastic range observed in micro-structural testing

Individual-specific multi-scale finite element simulation of cortical bone of human proximal femur

Energy Technology Data Exchange (ETDEWEB)

Ascenzi, Maria-Grazia, E-mail: mgascenzi@mednet.ucla.edu [UCLA/Orthopaedic Hospital, Department of Orthopaedic Surgery, Rehabilitation Bldg, Room 22-69, 1000 Veteran Avenue, University of California, Los Angeles, CA 90095 (United States); Kawas, Neal P., E-mail: nealkawas@ucla.edu [UCLA/Orthopaedic Hospital, Department of Orthopaedic Surgery, Rehabilitation Bldg, Room 22-69, 1000 Veteran Avenue, University of California, Los Angeles, CA 90095 (United States); Lutz, Andre, E-mail: andre.lutz@hotmail.de [Institute of Biomechanics and Numerical Mechanics, Leibniz University Hannover, 30167 Hannover (Germany); Kardas, Dieter, E-mail: kardas@ibnm.uni-hannover.de [ContiTech Vibration Control, Jaedekamp 30 None, 30419 Hannover (Germany); Nackenhorst, Udo, E-mail: nackenhorst@ibnm.uni-hannover.de [Institute of Biomechanics and Numerical Mechanics, Leibniz University Hannover, 30167 Hannover (Germany); Keyak, Joyce H., E-mail: jhkeyak@uci.edu [Department of Radiological Sciences, Medical Sciences I, Bldg 811, Room B140, University of California, Irvine, CA 92697-5000 (United States)

2013-07-01

We present an innovative method to perform multi-scale finite element analyses of the cortical component of the femur using the individual’s (1) computed tomography scan; and (2) a bone specimen obtained in conjunction with orthopedic surgery. The method enables study of micro-structural characteristics regulating strains and stresses under physiological loading conditions. The analysis of the micro-structural scenarios that cause variation of strain and stress is the first step in understanding the elevated strains and stresses in bone tissue, which are indicative of higher likelihood of micro-crack formation in bone, implicated in consequent remodeling or macroscopic bone fracture. Evidence that micro-structure varies with clinical history and contributes in significant, but poorly understood, ways to bone function, motivates the method’s development, as does need for software tools to investigate relationships between macroscopic loading and micro-structure. Three applications – varying region of interest, bone mineral density, and orientation of collagen type I, illustrate the method. We show, in comparison between physiological loading and simple compression of a patient’s femur, that strains computed at the multi-scale model’s micro-level: (i) differ; and (ii) depend on local collagen-apatite orientation and degree of calcification. Our findings confirm the strain concentration role of osteocyte lacunae, important for mechano-transduction. We hypothesize occurrence of micro-crack formation, leading either to remodeling or macroscopic fracture, when the computed strains exceed the elastic range observed in micro-structural testing.

Effects of Al2O3 and/or CaO on properties of yttria stabilized zirconia electrolyte doped with multi-elements

International Nuclear Information System (INIS)

Lv Zhengang; Guo Ruisong; Yao Pei; Dai Fengying

2007-01-01

Yttria stabilized zirconia (YSZ) has a high oxide ion conductivity at high temperatures. Some rare earth elements (e.g., Yb, Sc, Dy) with similar cation radii to Zr 4+ can dissolve into ZrO 2 , increasing its vacancy concentration and crystal lattice distortion, and therefore enhancing its conductivity and lowering the activation energy. It is expected this material could be used as intermediate temperature electrolyte. In the present work, YSZ electrolyte materials doped by multi-elements (Sc 2 O 3 or Dy 2 O 3 and Yb 2 O 3 ) were prepared by high temperature solid-state method. The high temperature conductivity was improved obviously, reaching 0.18 S/cm at 1000 deg. C, but the density and mechanical properties of sintered materials were not sufficiently high. It is found that sinterability and mechanical properties could be improved by inclusion of a small amount of Al 2 O 3 and/or CaO into the multi-elements doped YSZ materials and our results proved it. The results showed density and bending strength of sintered bodies were enhanced by Al 2 O 3 addition by 4.6% and 30%, respectively, while the conductivity did not degrade remarkably. But the degradation in bending strength and conductivity resulting from the CaO addition happened due to the second phase formed at the grain boundary. XRD patterns showed that all samples had cubic fluorite structure and crystalline lattice parameter was increased. SEM photographs obviously revealed the grain growth for the samples with CaO inclusion

Comparison of Different Assembling Techniques Regarding Cost, Durability, and Ecology - A Survey of Multi-layer Wooden Panel Assembly Load-Bearing Construction Elements

Directory of Open Access Journals (Sweden)

Dietrich Buck

2015-10-01

Full Text Available Wood is a pure, sustainable, renewable material. The increasing use of wood for construction can improve its sustainability. There are various techniques to assemble multi-layer wooden panels into prefabricated, load-bearing construction elements. However, comparative market and economy studies are still scarce. In this study, the following assembling techniques were compared: laminating, nailing, stapling, screwing, stress laminating, doweling, dovetailing, and wood welding. The production costs, durability, and ecological considerations were presented. This study was based on reviews of published works and information gathered from 27 leading wood product manufacturing companies in six European countries. The study shows that the various techniques of assembling multi-layer wooden construction panel elements are very different. Cross laminated timber (CLT exhibited the best results in terms of cost and durability. With regard to ecological concerns, dovetailing is the best. Taking into account both durability and ecological considerations, wooden screw-doweling is the best. These alternatives give manufacturers some freedom of choice regarding the visibility of surfaces and the efficient use of lower-quality timber. CLT is the most cost-effective, is not patented, and is a well-established option on the market today.

Disassembly and physical separation of electric/electronic components layered in printed circuit boards (PCB).

Science.gov (United States)

Lee, Jaeryeong; Kim, Youngjin; Lee, Jae-chun

2012-11-30

Although printed circuit boards (PCBs) contain various elements, only the major elements (i.e., those with content levels in wt% or over grade) of and precious metals (e.g., Ag, Au, and platinum groups) contained within PCBs can be recycled. To recover other elements from PCBs, the PCBs should be properly disassembled as the first step of the recycling process. The recovery of these other elements would be beneficial for efforts to conserve scarce resources, reuse electric/electronic components (EECs), and eliminate environmental problems. This paper examines the disassembly of EECs from wasted PCBs (WPCBs) and the physical separation of these EECs using a self-designed disassembling apparatus and a 3-step separation process of sieving, magnetic separation, and dense medium separation. The disassembling efficiencies were evaluated by using the ratio of grinding area (E(area)) and the weight ratio of the detached EECs (E(weight)). In the disassembly treatment, these efficiencies were improved with an increase of grinder speed and grinder height. 97.7% (E(area)) and 98% (E(weight)) could be accomplished ultimately by 3 repetitive treatments at a grinder speed of 5500 rpm and a grinder height of 1.5mm. Through a series of physical separations, most groups of the EECs (except for the diode, transistor, and IC chip groups) could be sorted at a relatively high separation efficiency of about 75% or more. To evaluate the separation efficiency with regard to the elemental composition, the distribution ratio (R(dis)) and the concentration ratio (R(conc)) were used. 15 elements could be separated with the highest R(dis) and R(conc) in the same separated division. This result implies that the recyclability of the elements is highly feasible, even though the initial content in EECs is lower than several tens of mg/kg. Copyright © 2012 Elsevier B.V. All rights reserved.

Cyclical subnormal separation in A-groups

International Nuclear Information System (INIS)

Makarfi, M.U.

1995-12-01

Three main results, concerning A-groups in respect of cyclical subnormal separation as defined in, are presented. It is shown in theorem A that any A-group that is generated by elements of prime order and satisfying the cyclical subnormal separation conditions is metabelian. The two other main results give necessary and sufficient conditions for A-groups, that are split extensions of certain abelian p-groups by a metabelian p'-group, to satisfy the cyclical subnormal separation condition. There is also a result which shows that A-groups with elementary abelian Sylow subgroups are cyclically separated as defined. (author). 7 refs

Separation and Recycling for Rare Earth Elements by Homogeneous Liquid-Liquid Extraction (HoLLE Using a pH-Responsive Fluorine-Based Surfactant

Directory of Open Access Journals (Sweden)

Shotaro Saito

2015-08-01

Full Text Available A selective separation and recycling system for metal ions was developed by homogeneous liquid-liquid extraction (HoLLE using a fluorosurfactant. Sixty-two different elemental ions (e.g., Ag, Al, As, Au, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, In, Ir, La, Lu, Mg, Mn, Mo, Nb, Nd, Ni, Os, P, Pb, Pd, Pr, Pt, Re, Rh, Ru, Sb, Sc, Se, Si, Sm, Sn, Sr, Ta, Tb, Te, Ti, Tl, Tm, V, W, Y, Yb, Zn, and Zr were examined. By changing pH from a neutral or alkaline solution (pH ≥ 6.5 to that of an acidic solution (pH < 4.0, gallium, zirconium, palladium, silver, platinum, and rare earth elements were extracted at >90% efficiency into a sedimented Zonyl FSA® (CF3(CF2n(CH22S(CH22COOH, n = 6–8 liquid phase. Moreover, all rare earth elements were obtained with superior extraction and stripping percentages. In the recycling of rare earth elements, the sedimented phase was maintained using a filter along with a mixed solution of THF and 1 M sodium hydroxide aqueous solution. The Zonyl FSA® was filtrated and the rare earth elements were recovered on the filter as a hydroxide. Furthermore, the filtrated Zonyl FSA was reusable by conditioning the subject pH.

A Finite Element Method for Simulation of Compressible Cavitating Flows

Science.gov (United States)

Shams, Ehsan; Yang, Fan; Zhang, Yu; Sahni, Onkar; Shephard, Mark; Oberai, Assad

2016-11-01

This work focuses on a novel approach for finite element simulations of multi-phase flows which involve evolving interface with phase change. Modeling problems, such as cavitation, requires addressing multiple challenges, including compressibility of the vapor phase, interface physics caused by mass, momentum and energy fluxes. We have developed a mathematically consistent and robust computational approach to address these problems. We use stabilized finite element methods on unstructured meshes to solve for the compressible Navier-Stokes equations. Arbitrary Lagrangian-Eulerian formulation is used to handle the interface motions. Our method uses a mesh adaptation strategy to preserve the quality of the volumetric mesh, while the interface mesh moves along with the interface. The interface jump conditions are accurately represented using a discontinuous Galerkin method on the conservation laws. Condensation and evaporation rates at the interface are thermodynamically modeled to determine the interface velocity. We will present initial results on bubble cavitation the behavior of an attached cavitation zone in a separated boundary layer. We acknowledge the support from Army Research Office (ARO) under ARO Grant W911NF-14-1-0301.

The Associative Structure of Memory for Multi-Element Events

Science.gov (United States)

2013-01-01

The hippocampus is thought to be an associative memory “convergence zone,” binding together the multimodal elements of an experienced event into a single engram. This predicts a degree of dependency between the retrieval of the different elements comprising an event. We present data from a series of studies designed to address this prediction. Participants vividly imagined a series of person–location–object events, and memory for these events was assessed across multiple trials of cued retrieval. Consistent with the prediction, a significant level of dependency was found between the retrieval of different elements from the same event. Furthermore, the level of dependency was sensitive both to retrieval task, with higher dependency during cued recall than cued recognition, and to subjective confidence. We propose a simple model, in which events are stored as multiple pairwise associations between individual event elements, and dependency is captured by a common factor that varies across events. This factor may relate to between-events modulation of the strength of encoding, or to a process of within-event “pattern completion” at retrieval. The model predicts the quantitative pattern of dependency in the data when changes in the level of guessing with retrieval task and confidence are taken into account. Thus, we find direct behavioral support for the idea that memory for complex multimodal events depends on the pairwise associations of their constituent elements and that retrieval of the various elements corresponding to the same event reflects a common factor that varies from event to event. PMID:23915127

Optics of mass separator I

International Nuclear Information System (INIS)

Balestrini, S.J.

1981-07-01

The ion optics of an existing mass separator are documented. The elctrostatic and magnetic stages are analyzed theoretically, both separately and in combination, by paying particular attention to the ion trajectories, the linear and angular magnifications, and the dispersion. The possibility of converting the magnet into a tunable unit by means of current-carrying elements in the gap is demonstrated. The feasibility of correction coils constructed from printed circuit board is shown

Optics of mass separator I

Energy Technology Data Exchange (ETDEWEB)

Balestrini, S.J.

1981-07-01

The ion optics of an existing mass separator are documented. The elctrostatic and magnetic stages are analyzed theoretically, both separately and in combination, by paying particular attention to the ion trajectories, the linear and angular magnifications, and the dispersion. The possibility of converting the magnet into a tunable unit by means of current-carrying elements in the gap is demonstrated. The feasibility of correction coils constructed from printed circuit board is shown.

Isolation of transplutonium elements from high-level radioactive wastes using diphenyl(dibutylcarbamoylmethyl)phosphine oxide

International Nuclear Information System (INIS)

Chmutova, M.K.; Litvina, M.N.; Pribylova, G.A.; Ivanova, L.A.; Myasoedov, B.F.; Smirnov, I.V.; Shadrin, A.Yu.

1999-01-01

Consequent stages of development of principal technological scheme of extraction separation of transplutonium elements from high-level radioactive wastes of spent fuel reprocessing are presented. Approach to reagent selection from the series of carbamoylmethylphosphine oxides is based. Distribution of transplutonium elements and accompanying elements between model solution of high-level radioactive wastes and solution of reagent in organic solvent is investigated. Methods of separation of transplutonium elements, reextraction of transplutonium elements together with rare earth elements are developed. Principal technological scheme of transplutonium elements separation from nonevaporated raffinates of spent fuel of WWER type reactors and method of separation of transplutonium and rare earth elements in weakly acid reextract with the use of liquid chromatography with free immobile phase are proposed [ru

Transactinide elements

International Nuclear Information System (INIS)

Hemingway, J.D.

1975-01-01

The review is covered in sections, entitled: predicted nuclear properties - including closed shells, decay characteristics; predicted chemical properties - including electronic structure and calculated properties, X-radiation, extrapolated chemical properties, separation chemistry; methods of synthesis; the natural occurrence of superheavy elements. (U.K.)

Representation of individual elements of a complex call sequence in primary auditory cortex

Directory of Open Access Journals (Sweden)

Mark Nelson Wallace

2013-10-01

Full Text Available Conspecific communication calls can be rhythmic or contain extended, discontinuous series of either constant or frequency modulated harmonic tones and noise bursts separated by brief periods of silence. In the guinea pig, rhythmic calls can produce isomorphic responses within the primary auditory cortex (AI where single units respond to every call element. Other calls such as the chutter comprise a series of short irregular syllables that vary in their spectral content and are more like human speech. These calls can also evoke isomorphic responses, but may only do so in fields in the auditory belt and not in AI. Here we present evidence that cells in AI treat the individual elements within a syllable as separate auditory objects and respond selectively to one or a subset of them. We used a single chutter exemplar to compare single/multi-unit responses in the low-frequency portion of AI - AI(LF and the low-frequency part of the thalamic medial geniculate body - MGB(LF in urethane anaesthetised guinea pigs. Both thalamic and cortical cells responded with brief increases in firing rate to one, or more, of the 8 main elements present in the chutter call. Almost none of the units responded to all 8 elements. While there were many different combinations of responses to between one and five of the elements, MBG(LF and AI(LF neurons exhibited the same specific types of response combinations. Nearby units in the upper layers of the cortex tended to respond to similar combinations of elements while the deep layers were less responsive. Thus the responses from a number of AI units would need to be combined in order to represent the entire chutter call. Our results don’t rule out the possibility of constructive convergence but there was no evidence that a convergence of inputs within AI led to a complete representation of all eight elements.

Slow-roll corrections in multi-field inflation: a separate universes approach

Science.gov (United States)

Karčiauskas, Mindaugas; Kohri, Kazunori; Mori, Taro; White, Jonathan

2018-05-01

In view of cosmological parameters being measured to ever higher precision, theoretical predictions must also be computed to an equally high level of precision. In this work we investigate the impact on such predictions of relaxing some of the simplifying assumptions often used in these computations. In particular, we investigate the importance of slow-roll corrections in the computation of multi-field inflation observables, such as the amplitude of the scalar spectrum Pζ, its spectral tilt ns, the tensor-to-scalar ratio r and the non-Gaussianity parameter fNL. To this end we use the separate universes approach and δ N formalism, which allows us to consider slow-roll corrections to the non-Gaussianity of the primordial curvature perturbation as well as corrections to its two-point statistics. In the context of the δ N expansion, we divide slow-roll corrections into two categories: those associated with calculating the correlation functions of the field perturbations on the initial flat hypersurface and those associated with determining the derivatives of the e-folding number with respect to the field values on the initial flat hypersurface. Using the results of Nakamura & Stewart '96, corrections of the first kind can be written in a compact form. Corrections of the second kind arise from using different levels of slow-roll approximation in solving for the super-horizon evolution, which in turn corresponds to using different levels of slow-roll approximation in the background equations of motion. We consider four different levels of approximation and apply the results to a few example models. The various approximations are also compared to exact numerical solutions.

Application of ion exchangers

International Nuclear Information System (INIS)

Markhol, M.

1985-01-01

Existing methods of multi-element separation for radiochemical analysis are considered. The majority of existing methods is noted to be based on application of organic and inorganic ion exchangers. Distillation, coprecipitation, extraction as well as combination of the above methods are also used. Concrete flowsheets of multi-element separation are presented

Isotope separation process

International Nuclear Information System (INIS)

Lyon, R.K.

1976-01-01

The instant invention relates to a process for separating a material into two or more parts in each of which the abundances of the isotopes of a given element differ from the abundances of the isotopes of the same material in said material. In one embodiment, the invention relates to a method for the isotopically selective excitation of gas phase molecules by multiple infrared photon absorption followed by selective dissociation of said excited molecules by the absorption of a single photon of visible or ultraviolet light. This invention is useful for, but not limited to, the separation of the principal isotopes of uranium. 11 Claims, 2 Drawing Figures

Separation of uranium and plutonium isotopes for measurement by multi collector inductively coupled plasma mass spectroscopy

International Nuclear Information System (INIS)

Martinelli, R.E.; Hamilton, T.F.; Kehl, S.R.; Williams, R.W.

2009-01-01

Uranium (U) and plutonium (Pu) isotopes in coral soils, contaminated by nuclear weapons testing in the northern Marshall Islands, were isolated by ion-exchange chromatography and analyzed by mass spectrometry. The soil samples were spiked with 233 U and 242 Pu tracers, dissolved in minerals acids, and U and Pu isotopes isolated and purified on commercially available ion-exchange columns. The ion-exchange technique employed a TEVA R column coupled to a UTEVA R column. U and Pu isotope fractions were then further isolated using separate elution schemes, and the purified fractions containing U and Pu isotopes analyzed sequentially using multi-collector inductively coupled plasma mass spectrometer (MCICP-MS). High precision measurements of 234 U/ 235 U, 238 U/ 235 U, 236 U/ 235 U, and 240 Pu/ 239 Pu in soil samples were attained using the described methodology and instrumentation, and provide a basis for conducting more detailed assessments of the behavior and transfer of uranium and plutonium in the environment. (author)

Variational formulation of relaxed and multi-region relaxed magnetohydrodynamics

Science.gov (United States)

Dewar, R. L.; Yoshida, Z.; Bhattacharjee, A.; Hudson, S. R.

2015-12-01

> Ideal magnetohydrodynamics (IMHD) is strongly constrained by an infinite number of microscopic constraints expressing mass, entropy and magnetic flux conservation in each infinitesimal fluid element, the latter preventing magnetic reconnection. By contrast, in the Taylor relaxation model for formation of macroscopically self-organized plasma equilibrium states, all these constraints are relaxed save for the global magnetic fluxes and helicity. A Lagrangian variational principle is presented that leads to a new, fully dynamical, relaxed magnetohydrodynamics (RxMHD), such that all static solutions are Taylor states but also allows state with flow. By postulating that some long-lived macroscopic current sheets can act as barriers to relaxation, separating the plasma into multiple relaxation regions, a further generalization, multi-region relaxed magnetohydrodynamics (MRxMHD) is developed.

Automated rapid chemistry in heavy element research

International Nuclear Information System (INIS)

Schaedel, M.

1994-01-01

With the increasingly short half-lives of the heavy element isotopes in the transition region from the heaviest actinides to the transactinide elements the demand for automated rapid chemistry techniques is also increasing. Separation times of significantly less than one minute, high chemical yields, high repetition rates, and an adequate detection system are prerequisites for many successful experiments in this field. The development of techniques for separations in the gas phase and in the aqueous phase for applications of chemical or nuclear studies of the heaviest elements are briefly outlined. Typical examples of results obtained with automated techniques are presented for studies up to element 105, especially those obtained with the Automated Rapid Chemistry Apparatus, ARCA. The prospects to investigate the properties of even heavier elements with chemical techniques are discussed

Comparative Study on Interface Elements, Thin-Layer Elements, and Contact Analysis Methods in the Analysis of High Concrete-Faced Rockfill Dams

Directory of Open Access Journals (Sweden)

Xiao-xiang Qian

2013-01-01

Full Text Available This paper presents a study on the numerical performance of three contact simulation methods, namely, the interface element, thin-layer element, and contact analysis methods, through the analysis of the contact behavior between the concrete face slab and the dam body of a high concrete-faced rockfill dam named Tianshengqiao-I in China. To investigate the accuracy and limitations of each method, the simulation results are compared in terms of the dam deformation, contact stress along the interface, stresses in the concrete face slab, and separation of the concrete face slab from the cushion layer. In particular, the predicted dam deformation and slab separation are compared with the in-situ observation data to classify these methods according to their agreement with the in-situ observations. It is revealed that the interface element and thin-layer element methods have their limitations in predicting contact stress, slab separation, and stresses in the concrete face slab if a large slip occurs. The contact analysis method seems to be the best choice whether the separation is finite or not.

Determination of refractory trace elements in Chinese meteorites by RNAA

International Nuclear Information System (INIS)

Kraehenbuehl, U.; Burger, M.

1989-01-01

Some refractory trace elements are important target elements for spallation reactions in meteorites. These elements also serve to characterize the investigated meteorites. The elements Ti, Y, Zr, Hf, W and Ta were measured after radiochemical separation in chondrites from China. After acid digestion of the irradiated samples, the group separations were obtained by precipitation reactions. The necessary radiochemical purification of the pure β emitter Y was realized on a Lewatite OC 1026 column. For all the other elements discrete gamma radiation was measured. (orig.)

Recovery of trans-plutonium elements; Recuperation des elements transplutoniens

Energy Technology Data Exchange (ETDEWEB)

Espie, J Y; Poncet, B; Simon, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1970-07-01

The object of this work is to study the recovery of americium and curium from the fission-product solution obtained from the processing of irradiated fuel elements made of natural metallic uranium alloyed with aluminium, iron and silicon; these elements have been subjected to an average irradiation of 4000 MW days/ton in a gas-graphite type reactor having a thermal power of 3.7 MW/ton of uranium. The process used consists of 3 extraction cycles and one americium-curium separation: - 1) extraction cycle in 40 per cent TBP: extraction of actinides and lanthanides; elimination of fission products; - 2) extraction cycle in 8 per cent D2EHPA: decontamination from the fission products, decontamination of actinides from lanthanides; - 3) extraction cycle in 40 per cent TBP: separation of the complexing agent and concentration of the actinides; - 4) americium-curium separation by precipitation. (authors) [French] Cette etude a pour objet, la recuperation de l'americium et du curium de la solution de produits de fission provenant du traitement de combustibles irradies a base d'uranium naturel metallique allie a l'aluminium, le fer, et le silicium, et ayant subi une irradiation moyenne de 4000 MWj/t dans une pile du type graphite-gaz, dont la puissance thermique est de 3.7 MW/t d'uranium. Le procede utilise comprend 3 cycles d'extraction et une separation americium-curium: - 1. cycle d'extraction dans le TBP a 40 pour cent: extraction des actinides et des lanthanides, elimination des produits de fission; - 2. cycle d'extraction dans le D2EHPA a 8 pour cent: decontamination en produits de fission, decontamination des actinides en lanthanides; - 3. cycle d'extraction dans le TBP a 40 pour cent: separation du complexant et concentration des actinides; - 4. separation americium-curium par precipitation. (auteurs)

Centrifugal gas separator

Energy Technology Data Exchange (ETDEWEB)

Kanagawa, A; Fujii, O; Nakamoto, H

1970-03-09

Counter currents in the rotary drum of a centrifugal gas separator are produced by providing, at either end of the drum in the vicinity of the circumferential and central positions, respectively, outflow and inflow holes with a communicating passage external to the drum there between whereby gaseous counter currents are caused to flow within the drum and travel through the passage which is provided with gas flow adjustment means. Furthermore, the space defined by the stationary portion of the passage and the rotor drum is additionally provided with a screw pump or throttling device at either its stationary side or drum side or both in order to produce a radially directed gas flow therewithin. A gas mixture is axially admitted into the drum while centrifugal force and a cooling element provided therebelow cause an increase in gas pressure along and a gaseous flow toward the wall member, whereupon the comparatively high pressured circumferentially distributed gas is extracted from the outlet holes, flows through the external gas passage and back into the lower pressured drum core through the inlet holes, thus producing the desired counter currents. The gases thus separated are withdrawn along axially provided discharge pipes. Accordingly, this invention permits heating elements which were formerly used to produce thermal convection currents to be disposed of and allows the length of the rotor drum to be more efficiently utilized to enhance separation efficiency.

Modelling optimization involving different types of elements in finite element analysis

International Nuclear Information System (INIS)

Wai, C M; Rivai, Ahmad; Bapokutty, Omar

2013-01-01

Finite elements are used to express the mechanical behaviour of a structure in finite element analysis. Therefore, the selection of the elements determines the quality of the analysis. The aim of this paper is to compare and contrast 1D element, 2D element, and 3D element used in finite element analysis. A simple case study was carried out on a standard W460x74 I-beam. The I-beam was modelled and analyzed statically with 1D elements, 2D elements and 3D elements. The results for the three separate finite element models were compared in terms of stresses, deformation and displacement of the I-beam. All three finite element models yield satisfactory results with acceptable errors. The advantages and limitations of these elements are discussed. 1D elements offer simplicity although lacking in their ability to model complicated geometry. 2D elements and 3D elements provide more detail yet sophisticated results which require more time and computer memory in the modelling process. It is also found that the choice of element in finite element analysis is influence by a few factors such as the geometry of the structure, desired analysis results, and the capability of the computer

Dynamic separation of nanomagnet sublattices by orientation of elliptical elements

Science.gov (United States)

Yahagi, Y.; Berk, C. R.; Harteneck, B. D.; Cabrini, S. D.; Schmidt, H.

2014-04-01

We report the separation of the magnetization dynamics of densely packed nanomagnets depending on their orientation. The arrays consist of interleaved sublattices of identical nickel elliptical disks. By controlling the orientation of the elliptic disks relative to the external field in each sublattice, we simultaneously analyzed the magnetization dynamics in each sublattice using a time-resolved magnetooptic Kerr effect (TR-MOKE) microscopy system. The Fourier spectra showed clearly separated precession modes for sublattices with different orientations. The spectra were shown to be robust against the error in applied field orientation. The sublattice response can be tuned to a single collective frequency by choosing a symmetric field orientation. We analyzed the effect of the interelement coupling with various spacing between nanomagnets and found a relatively weak dependence on dipolar interactions in good agreement with micromagnetic simulations.

Fabrication of Separator Demonstration Facility process vessel

International Nuclear Information System (INIS)

Oberst, E.F.

1985-01-01

The process vessel system is the central element in the Separator Development Facility (SDF). It houses the two major process components, i.e., the laser-beam folding optics and the separators pods. This major subsystem is the critical-path procurement for the SDF project. Details of the vaious parts of the process vessel are given

Quadratic inner element subgrid scale discretisation of the Boltzmann transport equation

International Nuclear Information System (INIS)

Baker, C.M.J.; Buchan, A.G.; Pain, C.C.; Tollit, B.; Eaton, M.D.; Warner, P.

2012-01-01

This paper explores the application of the inner element subgrid scale method to the Boltzmann transport equation using quadratic basis functions. Previously, only linear basis functions for both the coarse scale and the fine scale were considered. This paper, therefore, analyses the advantages of using different coarse and subgrid basis functions for increasing the accuracy of the subgrid scale method. The transport of neutral particle radiation may be described by the Boltzmann transport equation (BTE) which, due to its 7 dimensional phase space, is computationally expensive to resolve. Multi-scale methods offer an approach to efficiently resolve the spatial dimensions of the BTE by separating the solution into its coarse and fine scales and formulating a solution whereby only the computationally efficient coarse scales need to be solved. In previous work an inner element subgrid scale method was developed that applied a linear continuous and discontinuous finite element method to represent the solution’s coarse and fine scale components. This approach was shown to generate efficient and stable solutions, and so this article continues its development by formulating higher order quadratic finite element expansions over the continuous and discontinuous scales. Here it is shown that a solution’s convergence can be improved significantly using higher order basis functions. Furthermore, by using linear finite elements to represent coarse scales in combination with quadratic fine scales, convergence can also be improved with only a modest increase in computational expense.

Long-term program for research and development of group separation and disintegration techniques

International Nuclear Information System (INIS)

1988-01-01

In Japan, the basic guidelines state that high-level radioactive wastes released from reprocessing of spent fuel should be processed into stable solid material, followed by storage for cooling for 30-50 years and disposal in the ground at a depth of several hundreds of meters. The Long-Term Program for Research and Development of Group Separation and Disintegration Techniques is aimed at efficient disposal of high-level wastes, reutilization of useful substances contained, and improved safety. Important processes include separation of nuclides (group separation, individual nuclide separation) and conversion (disintegration) of long-lived nuclides into short-lived or non-radioactive one. These processes can reduce the volume of high-level wastes to be left for final disposal. Research and development projects have been under way to provide techniques to separate high-level waste substances into four groups (transuranic elements, strontium/cesium, technetium/platinum group elements, and others). These projects also cover recovery of useful metals and efficient utilization of separated substances. For disintegration, conceptual studies have been carried out for the application of fast neutron beams to conversion of long half-life transuranium elements into short half-life or non-radioactive elements. (N.K.)

Methods for separation of actinides

International Nuclear Information System (INIS)

Keller, C.

1976-01-01

Methods of actinoids separation are reviewed, including precipitation, sublimation, paper chromatography and electrophoresis. Compounds typically used for co-precipitation of actinoid ions are listed. Ion-exchange methods considered include cation and ion exchange. Factors are described, which affect the efficiency of separation of transuranium elements in the same degrees of oxidation: complex-forming agents, temperature, ion-exchange resin, rate of elution, the size of the column, the influence of salts. Extraction of actinoid ions upon formation of solvate complexes, inner complex compounds and metal salts is discussed. Combining the advantages of ion exchange and extraction, the method of extraction chromatography can be widely used for separation of actinoids

Multi-element analyses of Vietnamese environmental samples for radiation protection

International Nuclear Information System (INIS)

Mai, T.H.; Nguyen, T.B.; Nguyen, T.N.; Yoshida, S.

2005-01-01

The Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) were used for measuring 8 major and 27 trace elements in food and soil samples collected in Vietnam. The concentration of elements in food samples was different from different locations and also from different food groups. Depth profiles of the elements were discussed for soil samples. (author)

Spectrometer system using a modular echelle spectrograph and a laser-driven continuum source for simultaneous multi-element determination by graphite furnace absorption spectrometry

Energy Technology Data Exchange (ETDEWEB)

Geisler, Sebastian; Okruss, Michael; Becker-Ross, Helmut; Huang, Mao Dong, E-mail: huang@isas.de; Esser, Norbert; Florek, Stefan

2015-05-01

A multi-element absorption spectrometer system has been developed based on a laser-driven xenon continuum source and a modular simultaneous echelle spectrograph (MOSES), which is characterized by a minimized number of optical components resulting in high optical throughput, high transmittance and high image quality. The main feature of the new optical design is the multifunction usage of a Littrow prism, which is attached on a rotation stage. It operates as an order-sorter for the echelle grating in a double-pass mode, as a fine positioning device moving the echelle spectrum on the detector, and as a forwarder to address different optical components, e.g., echelle gratings, in the setup. Using different prisms, which are mounted back to back on the rotation stage, a multitude of different spectroscopic modes like broad-range panorama observations, specific UV–VIS and NIR studies or high resolution zoom investigations of variable spectral channels can be realized. In the UV panorama mode applied in this work, MOSES has simultaneously detectable wavelength coverage from 193 nm to 390 nm with a spectral resolution λ/Δλ of 55,000 (3-pixel criterion). In the zoom mode the latter can be further increased by a factor of about two for a selectable section of the full wavelength range. The applicability and the analytical performance of the system were tested by simultaneous element determination in a graphite furnace, using eight different elements. Compared to an instrument operating in the optimized single line mode, the achieved analytical sensitivity using the panorama mode was typically a factor of two lower. Using the zoom mode for selected elements, comparable sensitivities were obtained. The results confirm the influence of the different spectral resolutions. - Highlights: • Echelle spectrometer with a full frame CCD array detector • High and variable spectral resolution from λ/Δλ of 55,000 to 95,000 • Laser-driven continuum light source �

Optimizing survivability of multi-state systems with multi-level protection by multi-processor genetic algorithm

International Nuclear Information System (INIS)

Levitin, Gregory; Dai Yuanshun; Xie Min; Leng Poh, Kim

2003-01-01

In this paper we consider vulnerable systems which can have different states corresponding to different combinations of available elements composing the system. Each state can be characterized by a performance rate, which is the quantitative measure of a system's ability to perform its task. Both the impact of external factors (stress) and internal causes (failures) affect system survivability, which is determined as probability of meeting a given demand. In order to increase the survivability of the system, a multi-level protection is applied to its subsystems. This means that a subsystem and its inner level of protection are in their turn protected by the protection of an outer level. This double-protected subsystem has its outer protection and so forth. In such systems, the protected subsystems can be destroyed only if all of the levels of their protection are destroyed. Each level of protection can be destroyed only if all of the outer levels of protection are destroyed. We formulate the problem of finding the structure of series-parallel multi-state system (including choice of system elements, choice of structure of multi-level protection and choice of protection methods) in order to achieve a desired level of system survivability by the minimal cost. An algorithm based on the universal generating function method is used for determination of the system survivability. A multi-processor version of genetic algorithm is used as optimization tool in order to solve the structure optimization problem. An application example is presented to illustrate the procedure presented in this paper

Simultaneous speciation of trace elements using chemical separation and neutron activation

International Nuclear Information System (INIS)

Chatt, A.

2003-01-01

Speciation neutron activation analysis (SNAA) is a sophisticated analytical technique which can be developed for studying the simultaneous speciation of a number of elements in a variety of matrices. The advantages of SNAA are demonstrated with typical examples such as (i) arsenic speciation in sea foods and water, and simultaneous speciation of (ii) arsenic, antimony and selenium in water, (iii) chlorine, bromine and iodine in fish, (iv) lanthanides in simulated vitrified waste, and (v) trace elements bound to proteins. (author)

MONSS: A multi-objective nonlinear simplex search approach

Science.gov (United States)

Zapotecas-Martínez, Saúl; Coello Coello, Carlos A.

2016-01-01

This article presents a novel methodology for dealing with continuous box-constrained multi-objective optimization problems (MOPs). The proposed algorithm adopts a nonlinear simplex search scheme in order to obtain multiple elements of the Pareto optimal set. The search is directed by a well-distributed set of weight vectors, each of which defines a scalarization problem that is solved by deforming a simplex according to the movements described by Nelder and Mead's method. Considering an MOP with n decision variables, the simplex is constructed using n+1 solutions which minimize different scalarization problems defined by n+1 neighbor weight vectors. All solutions found in the search are used to update a set of solutions considered to be the minima for each separate problem. In this way, the proposed algorithm collectively obtains multiple trade-offs among the different conflicting objectives, while maintaining a proper representation of the Pareto optimal front. In this article, it is shown that a well-designed strategy using just mathematical programming techniques can be competitive with respect to the state-of-the-art multi-objective evolutionary algorithms against which it was compared.

Separability of three qubit Greenberger-Horne-Zeilinger diagonal states

Science.gov (United States)

Han, Kyung Hoon; Kye, Seung-Hyeok

2017-04-01

We characterize the separability of three qubit GHZ diagonal states in terms of entries. This enables us to check separability of GHZ diagonal states without decomposition into the sum of pure product states. In the course of discussion, we show that the necessary criterion of Gühne (2011 Entanglement criteria and full separability of multi-qubit quantum states Phys. Lett. A 375 406-10) for (full) separability of three qubit GHZ diagonal states is sufficient with a simpler formula. The main tool is to use entanglement witnesses which are tri-partite Choi matrices of positive bi-linear maps.

Permission-based separation logic for multi-threaded Java programs

NARCIS (Netherlands)

Amighi, A.; Haack, Christian; Huisman, Marieke; Hurlin, C.

This paper presents a program logic for reasoning about multithreaded Java-like programs with concurrency primitives such as dynamic thread creation, thread joining and reentrant object monitors. The logic is based on concurrent separation logic. It is the first detailed adaptation of concurrent

Finite element modelling

International Nuclear Information System (INIS)

Tonks, M.R.; Williamson, R.; Masson, R.

2015-01-01

The Finite Element Method (FEM) is a numerical technique for finding approximate solutions to boundary value problems. While FEM is commonly used to solve solid mechanics equations, it can be applied to a large range of BVPs from many different fields. FEM has been used for reactor fuels modelling for many years. It is most often used for fuel performance modelling at the pellet and pin scale, however, it has also been used to investigate properties of the fuel material, such as thermal conductivity and fission gas release. Recently, the United Stated Department Nuclear Energy Advanced Modelling and Simulation Program has begun using FEM as the basis of the MOOSE-BISON-MARMOT Project that is developing a multi-dimensional, multi-physics fuel performance capability that is massively parallel and will use multi-scale material models to provide a truly predictive modelling capability. (authors)

Diffusion of elements and vacancies in multi-component systems

Czech Academy of Sciences Publication Activity Database

Fischer, F. D.; Svoboda, Jiří

2014-01-01

Roč. 60, MAR (2014), s. 338-367 ISSN 0079-6425 Institutional support: RVO:68081723 Keywords : multi-component diffusion * vacancy activity * manning theory * stress-driven diffusion Subject RIV: BJ - Thermodynamics Impact factor: 27.417, year: 2014

Simulation Model of Membrane Gas Separator Using Aspen Custom Modeler

Energy Technology Data Exchange (ETDEWEB)

Song, Dong-keun [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of); Shin, Gahui; Yun, Jinwon; Yu, Sangseok [Chungnam Nat’l Univ., Daejeon (Korea, Republic of)

2016-12-15

Membranes are used to separate pure gas from gas mixtures. In this study, three different types of mass transport through a membrane were developed in order to investigate the gas separation capabilities of a membrane. The three different models typically used are a lumped model, a multi-cell model, and a discretization model. Despite the multi-cell model producing similar results to a discretization model, the discretization model was selected for this investigation, due to the cell number dependence of a multi-cell model. The mass transport model was then used to investigate the effects of pressure difference, flow rate, total exposed area, and permeability. The results showed that the pressure difference increased with the stage cut, but the selectivity was a trade-off for the increasing pressure difference. Additionally, even though permeability is an important parameter, the selectivity and stage cut of the membrane converged as permeability increased.

Mansion, A Distributed Multi-Agent System

NARCIS (Netherlands)

van t Noordende, G.; Brazier, F.M.; Tanenbaum, A.S.

2001-01-01

In this position summary we present work in progress on a worldwide, scalable multi-agent system, based on a paradigm of hyperlinked rooms. The framework offers facilities for managing distribution, security and mobility aspects for both active elements (agents) and passive elements (objects) in the

Quantitative real-time monitoring of multi-elements in airborne particulates by direct introduction into an inductively coupled plasma mass spectrometer

International Nuclear Information System (INIS)

Suzuki, Yoshinari; Sato, Hikaru; Hiyoshi, Katsuhiro; Furuta, Naoki

2012-01-01

A new calibration system for real-time determination of trace elements in airborne particulates was developed. Airborne particulates were directly introduced into an inductively coupled plasma mass spectrometer, and the concentrations of 15 trace elements were determined by means of an external calibration method. External standard solutions were nebulized by an ultrasonic nebulizer (USN) coupled with a desolvation system, and the resulting aerosol was introduced into the plasma. The efficiency of sample introduction via the USN was calculated by two methods: (1) the introduction of a Cr standard solution via the USN was compared with introduction of a Cr(CO) 6 standard gas via a standard gas generator and (2) the aerosol generated by the USN was trapped on filters and then analyzed. The Cr introduction efficiencies obtained by the two methods were the same, and the introduction efficiencies of the other elements were equal to the introduction efficiency of Cr. Our results indicated that our calibration method for introduction efficiency worked well for the 15 elements (Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Sn, Sb, Ba, Tl and Pb). The real-time data and the filter-collection data agreed well for elements with low-melting oxides (V, Co, As, Mo, Sb, Tl, and Pb). In contrast, the real-time data were smaller than the filter-collection data for elements with high-melting oxides (Ti, Cr, Mn, Ni, Cu, Zn, Sn, and Ba). This result implies that the oxides of these 8 elements were not completely fused, vaporized, atomized, and ionized in the initial radiation zone of the inductively coupled plasma. However, quantitative real-time monitoring can be realized after correction for the element recoveries which can be calculated from the ratio of real-time data/filter-collection data. - Highlights: ► APs were directly introduced into ICP-MS and real-time analysis was performed. ► The real-time data were calibrated by a multi-element standard solution from USN. ► During real

A High-Throughput SU-8Microfluidic Magnetic Bead Separator

DEFF Research Database (Denmark)

Bu, Minqiang; Christensen, T. B.; Smistrup, Kristian

2007-01-01

We present a novel microfluidic magnetic bead separator based on SU-8 fabrication technique for high through-put applications. The experimental results show that magnetic beads can be captured at an efficiency of 91 % and 54 % at flow rates of 1 mL/min and 4 mL/min, respectively. Integration...... of soft magnetic elements in the chip leads to a slightly higher capturing efficiency and a more uniform distribution of captured beads over the separation chamber than the system without soft magnetic elements....

Application of activation analysis for determination of some elements in cassiterite samples

International Nuclear Information System (INIS)

Armelin, Maria Jose Aguirre

1978-01-01

This work consists in the development of an analytical method using activation by thermal neutrons for the determination of some minor elements and traces present in cassiterite (tin ore). This method was then applied to determine these elements in samples of cassiterite from different regions of Brazil. An analysis was made of the mineralogy characteristic of cassiterite as well as of the minerals most commonly associated with it. Four main types of interference were found to occur in the analysis by activation of trace elements in samples of cassiterite. The method involves the analysis without chemical separation for the determination of some elements and the analysis with chemical separation for the determination of other elements. The steps involved in both types of analysis are described. In the analysis with chemical separation the matrix element (tin) is separated by distillation in an H 2 SO 4 -HBr medium, after fusion of the ore with Na 2 O 2 . Arsine and antimony are determined in the distilled, whereas some lanthanide elements and uranium are determined in the distillation residue by separating them as a group by precipitation with lanthanum fluoride. A discussion on the precision, accuracy and sensibility of the method is also included. (author)

2. Transuranic elements

International Nuclear Information System (INIS)

Anon.

1975-01-01

Methods of sample collection, sample storage, sample procedures and radioanalytical procedures for transuranic elements in marine environment are reviewed and recommended. Alpha spectrometry and scintillation techniques are used for measurement of isotopic content. Separation processes for samples are described

Optimization of the isotope separation in columns

International Nuclear Information System (INIS)

Kaminskij, V.A.; Vetsko, V.M.; Tevzadze, G.A.; Devdariani, O.A.; Sulaberidze, G.A.

1982-01-01

The general method for the multi-parameter optimization of cascade plants of packed columns is proposed. As an optimization effectiveness function a netcost of the isotopic product is selected. The net cost is comprehensively characterizing the sum total of capital costs for manufacturing the products as well as determining the choice of the most effective directions for capital investments and rational limits of improvement of the products quality. The method is based on main representations of the cascade theory, such as the ideal flow profile and form efficiency as well as mathematical model of the packed column specifying the bonds between its geometric and operating parameters. As a result, the isotopic products cost function could be bound with such parameters as the equilibrium stage height, ultimate packing capacity, its element dimensions, column diameter. It is concluded that the suggested approach to the optimization of isotope separation processes is rather a general one. It permits to solve a number of special problems, such as estimation of advisability of using heat-pump circuits and determining the rational automation level. Besides, by means of the method suggested one can optimize the process conditions with regard to temperature and pressure

Ion source development for the on-line isotope separator at GSI

International Nuclear Information System (INIS)