WorldWideScience

Sample records for heavy element separation

  1. 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.

  2. 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.

  3. Multiphoton spectroscopy in heavy elements

    Energy Technology Data Exchange (ETDEWEB)

    Solarz, R.W.; Paisner, J.A.; Worden, E.F.

    1977-05-03

    Some recently discovered regularities in the spectra of heavy elements which are also applicable to the analysis of the spectra of lighter atoms are described. It is pointed out that stepwise resonant multiphoton methods are irreplaceable tools in the study of high lying states in a complex atomic system. Systematic applications of these methods has permitted regularities to be observed which also hold for the lighter elements. It is noted that greatly increased understanding of the excited state structure of heavy atoms is not possible. 8 references. (JFP)

  4. Heavy element nucleosynthesis

    CERN Document Server

    Schramm, D N

    1976-01-01

    A review is made of current nuclear astrophysical theory regarding the origin of the elements heavier than iron. The pre-supernova evolution of stars is very briefly described, and speculation is given regarding the supernova mechanism. In particular, the possible role of weak neutral currents is presented. The synthesis of the trans-iron nuclei via the s and r-processes is examined. Special emphasis is given to the r-process because it depends completely on the properties of nuclei off the valley of stability. Recent explosive r-process calculations are discussed, as well as plausible astrophysical sites. The alternative n-process is also described. The possible production by the r and/or n-processes of the almost mythical superheavy elements is reviewed. The sensitivity of the results to certain crudely estimated parameters is explicitly shown. Throughout the discussion, the importance of certain nuclear physics experiments and formalism is demonstrated. Areas where advances in nuclear physics will have a d...

  5. Heavy Metals and Related Trace Elements.

    Science.gov (United States)

    Leland, Harry V.; And Others

    1978-01-01

    Presents a literature review of heavy metals and related trace elements in the environment, covering publications of 1976-77. This review includes: (1) trace treatment in natural water and in sediments; and (2) bioaccumulation and toxicity of trace elements. A list of 466 references is presented. (HM)

  6. Frontiers of heavy element nuclear and radiochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D.C.

    1997-10-01

    The production and half-lives of the heaviest chemical elements, now known through Z = 112, are reviewed. Recent experimental evidence for the stabilization of heavy element isotopes due to proximity to deformed nuclear shells at Z = 108 and N = 162 is compared with the theoretical predictions. The possible existence of isotopes of elements 107--110 with half-lives of seconds or longer, and production reactions and experimental techniques for increasing the overall yields of such isotopes in order to study both their nuclear and chemical properties are discussed. The present status of studies of the chemical properties of Rf, Ha, and Sg is briefly summarized and prospects for extending chemical studies beyond Sg are considered.

  7. Survival Mediated Heavy Element Capture Cross Sections

    Science.gov (United States)

    Loveland, Walter; Yao, Larry

    2017-11-01

    Formally, the cross section for producing a heavy evaporation residue, σEVR, in a fusion reaction can be written as where E is the center of mass energy, and T is the probability of the colliding nuclei to overcome the potential barrier in the entrance channel and reach the contact point. PCN is the probability that the projectile-target system will evolve from the contact point to the compound nucleus. Wsur is the probability that the compound nucleus will decay to produce an evaporation residue rather than fissioning. However, one must remember that the Wsur term effectively sets the allowed values of the spin, which in turn, restricts the values of the capture and fusion cross sections. We point out the implications of this fact for capture cross sections for heavy element formation reactions.

  8. Heavy metals in source-separated compost and digestates.

    Science.gov (United States)

    Kupper, Thomas; Bürge, Diane; Bachmann, Hans Jörg; Güsewell, Sabine; Mayer, Jochen

    2014-05-01

    The production of compost and digestate from source-separated organic residues is well established in Europe. However, these products may be a source of pollutants when applied to soils. In order to assess this issue, composts, solid and liquid digestates from Switzerland were analyzed for heavy metals (Cd, Co, Cr, Cu, Ni, Pb and Zn) addressing factors which may influence the concentration levels: the treatment process, the composition, origin, particle size and impurity content of input materials, the season of input materials collection or the degree of organic matter degradation. Composts (n=81) showed mean contents being at 60% or less of the legal threshold values. Solid digestates (n=20) had 20-50% lower values for Cd, Co, Pb and Zn but similar values for Cr, Cu and Ni. Liquid digestates (n=5) exhibited mean concentrations which were approximately twice the values measured in compost for most elements. Statistical analyses did not reveal clear relationships between influencing factors and heavy metal contents. This suggests that the contamination was rather driven by factors not addressed in the present study. According to mass balance calculations related to Switzerland, the annual loads to agricultural soils resulting from the application of compost and digestates ranged between 2% (Cd) and 22% (Pb) of total heavy metal loads. At regional scale, composts and digestates are therefore minor sources of pollution compared to manure (Co, Cu, Ni, Zn), mineral fertilizer (Cd, Cr) and aerial deposition (Pb). However, for individual fields, fertilization with compost or digestates results in higher heavy metal loads than application of equivalent nutrient inputs through manure or mineral fertilizer. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Heavy-element chemistry - Status and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Tuerler, A. [Paul Scherrer Institut, Villigen (Switzerland); Bern univ. (Switzerland)

    2002-10-01

    In the past ten years, nuclear chemists have made considerable progress in developing fast on-line separation techniques, which allowed to chemically characterize the first four transactinide elements Rf (rutherfordium, Z=104), Db (dubnium, Z=105), Sg (seaborgium, Z=106), and recently also Bh (bohrium, Z=107). In all cases the isolated nuclides were unambiguously identified by observing genetically linked decay chains. Nuclides with production cross-sections of less than 100 pb and half-lives as short as a few seconds have been chemically isolated. Thus, chemists have discovered or significantly contributed to the characterization of the nuclear-decay properties of a number of transactinide nuclei. New techniques with greatly improved overall efficiencies should allow chemists to extend their studies to even heavier elements such as Hs (hassium, Z=108) and to the recently discovered superheavy elements with Z=112 and 114, which can be produced only with picobarn cross-sections. (orig.)

  10. Survival Mediated Heavy Element Capture Cross Sections

    Directory of Open Access Journals (Sweden)

    Loveland Walter

    2017-01-01

    where E is the center of mass energy, and T is the probability of the colliding nuclei to overcome the potential barrier in the entrance channel and reach the contact point. PCN is the probability that the projectile-target system will evolve from the contact point to the compound nucleus. Wsur is the probability that the compound nucleus will decay to produce an evaporation residue rather than fissioning. However, one must remember that the Wsur term effectively sets the allowed values of the spin, which in turn, restricts the values of the capture and fusion cross sections. We point out the implications of this fact for capture cross sections for heavy element formation reactions.

  11. Preparation of targets by electrodeposition for heavy element studies

    Energy Technology Data Exchange (ETDEWEB)

    Eberhardt, K. E-mail: klaus.eberhardt@uni-mainz.de; Schaedel, M.; Schimpf, E.; Thoerle, P.; Trautmann, N

    2004-03-21

    For heavy element studies at GSI, lanthanide and actinide targets have been prepared by molecular plating. The deposition occurs from an isopropanolic solution at 1000-1200 V with current densities of a few mA/cm{sup 2}. Several lanthanide targets have been prepared for test experiments. With {sup nat}Gd deposited on a 10 {mu}m thick Be backing foil a target density of 1100 {mu}g/cm{sup 2} could be achieved. Gd-targets were used for the production of {alpha}-emitting isotopes of Os, the homologue of hassium (Hs; Z=108), in order to develop a chemical separation procedure for Hs. {sup 248}Cm targets with densities up to 730 {mu}g/cm{sup 2} have been produced for recent experiments to investigate the chemical behaviour of Hs. Here, a rotating wheel system with a multi-target device has been applied enabling higher beam intensities, compared to a stationary target. The targets were irradiated with a pulsed {sup 26}Mg{sup 5+} beam applying beam currents up to 6.6 {mu}A{sub electr}. An {alpha}-spectroscopic investigation of the irradiated Cm-targets showed that the Cm-material is not evenly distributed over the entire target area. Very often, for heavy element investigations, chemical separation procedures are required to ensure high purity of the deposited actinide materials.

  12. Actinide targets for the synthesis of super-heavy elements

    Energy Technology Data Exchange (ETDEWEB)

    Roberto, J.B., E-mail: robertojb@ornl.gov; Alexander, C.W.; Boll, R.A.; Burns, J.D.; Ezold, J.G.; Felker, L.K.; Hogle, S.L.; Rykaczewski, K.P.

    2015-12-15

    Since 2000, six new super-heavy elements with atomic numbers 113 through 118 have been synthesized in hot fusion reactions of {sup 48}Ca beams on actinide targets. These target materials, including {sup 242}Pu, {sup 244}Pu, {sup 243}Am, {sup 245}Cm, {sup 248}Cm, {sup 249}Cf, and {sup 249}Bk, are available in very limited quantities and require specialized production and processing facilities resident in only a few research centers worldwide. This report describes the production and chemical processing of heavy actinide materials for super-heavy element research, current availabilities of these materials, and related target fabrication techniques. The impact of actinide materials in super-heavy element discovery is reviewed, and strategies for enhancing the production of rare actinides including {sup 249}Bk, {sup 251}Cf, and {sup 254}Es are described.

  13. Element Distribution and Multiplicity of Heavy Fragments

    CERN Multimedia

    2002-01-01

    This experiment will measure the energy and angular distribution of heavy fragments produced in the reactions of |1|2C on several targets between |2|7Al and |2|3|8U at 86~MeV/u. The systematic investigation of a highly excited interaction region (fireball) by means of a clean N and Z identification of heavy tar fragments, may result in a better understanding of temperature concept and of the degree of equilibration of the local interaction region with respect to the total system. For this investigation a large-area position sensitive ionization chamber of 50~msr solid angle in conjunction with a time-of-flight telescope consisting of parallel-plate detectors will be used. \\\\ \\\\ In order to get information on the transverse momentum transfer and the inelasticity of the collision, the energy of the PROJECTILE-FRAGMENTS will be measured at forward angles with a plastic scintillator hodoscope. In addition to this inclusive measurement correlations between heavy fragments will be investigated by means of three pos...

  14. Heavy element research at FLNR (Dubna)

    Energy Technology Data Exchange (ETDEWEB)

    Oganessian, Yu. [Joint Institute for Nuclear Research, Flerov Laboratory of Nuclear Reactions, Moscow region, Dubna (Russian Federation)

    2009-12-15

    The setting of the experiments is described and the results obtained on the synthesis of the heaviest nuclides in reactions induced by {sup 48}Ca projectiles are presented. The decay properties of the new nuclei confirm the theoretical predictions about the new nuclear shells and the ''islands of stability'' of superheavy elements. Briefly, also the results of the first experiments aimed to study the atomic and chemical properties of element 112 are reported. (orig.)

  15. Selective liquid chromatographic separation of yttrium from heavier rare earth elements using acetic acid as a novel eluent.

    Science.gov (United States)

    Kifle, Dejene; Wibetoe, Grethe

    2013-09-13

    One of the major difficulties in the rare earth elements separation is purification of yttrium from heavy rare earth elements. Thus, an HPLC method using acetic acid as novel eluent was explored for selective separation of yttrium form the heavy rare earth elements. When acetic acid is used as a mobile phase yttrium eluted with the lighter lanthanides. This is contrary to its relative position amongst heavier lanthanides when eluents commonly used for separation of rare earth elements were employed. The shift in elution position of yttrium with acetic acid as eluent may reflect a relatively lower stability constant of the yttrium-AcOH complex (in the same order as for the lighter lanthanides) compared to the corresponding AcOH complexes with heavy lanthanides, enabling selective separation of yttrium from the latter. The method was successfully used for selective separation of yttrium in mixed rare earth sample containing about 80% of yttrium and about 20% of heavy rare earth oxides. Thus, the use of AcOH as eluent is an effective approach for separating and determining the trace amounts of heavy rare earth elements in large amounts of yttrium matrix. Separation was performed on C18 column by running appropriate elution programs. The effluent from the column was monitored with diode array detector at absorbance wavelength of 658nm after post column derivatization with Arsenazo III. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Determination of heavy elements in Nigerian river sediments using ...

    African Journals Online (AJOL)

    Energy Dispersive X-Ray Fluoresecence (EDXRF) Technique was used to determine eleven heavy elements (K, Ca, Ti, V, Fe, Co, Zn, Rb, Sr, Zr, Nb) from sediments of the Kubanni river in Nigeria. Six of them (K, Ca, Ti, Fe, Co, Sr) were found to be depleted, while lthe others were enriched with respect to their Clarke values.

  17. Alpha decay properties of heavy and superheavy elements

    Indian Academy of Sciences (India)

    properties of very heavy atomic nuclei. Elements with Z = 107−112 have been synthe- sized at GSI, Darmstadt [1,2] and their results gave a pronounced enlargement of lifetimes for Z = 106 − 118 nuclei. Based on this, here we apply our well-known cubic plus. Yukawa plus exponential (CYE) model which is successful in ...

  18. Selective Separation and Determination of Heavy Metals (Cd, Pb, Cr) Speciation Forms from Hortic Antrosols

    Science.gov (United States)

    Bulgariu, D.; Bulgariu, L.

    2009-04-01

    forms of heavy metals from glass houses soils has two main steps: (i) non-destructive separation of chemical-mineralogical associations and aggregates from soils samples - for this the separation method with heavy liquids (bromophorme) and isodynamic magnetic method have been used; (ii) sequential extraction of heavy metals from soil fractions separated in the first step, by using combined SPE-ABS procedure. For the preparation of combined extraction systems was used polyethylene glycol (with different molecular mass: 2000, 4000 and 8000). As phase-forming inorganic salts and as selective extracting agents we have used different usual inorganic reagents. The type and concentration of phase-forming salts have been selected in function of, both nature of extracted heavy metals and chemical-mineralogical characteristics of soil samples. The experimental parameters investigated in this study are: molecular mass of polyethylene glycol and the concentration of polymeric solutions, nature and concentration of phase-forming salts, nature and concentration of extracting agents, pH in extraction system phase, type of extracted heavy metals, type of speciation forms of heavy metals and their concentrations. All these factors can influence significantly the efficiency and the selectivity of separation process. The experimental results have indicate that the combined SPE-ABS extraction systems have better separation efficiency, in comparison with traditional SPE systems and ca realized a accurate discrimination between speciation forms of heavy metals from soils. Under these conditions, the estimation of inter-phases distribution and biodisponibility of heavy metals has a high precision. On the other hand, when the combined SPE-ABS systems are used, the concomitant extraction of the elements from the same geochemical association with studied heavy metals (inevitable phenomena in case of separation by SPE procedures) is significant diminished. This increases the separation

  19. Antioxidant, Heavy Metals and Elemental Analysis of Holoptelea integrifolia Planch

    OpenAIRE

    Saraswathy, A.; Devi, S. Nandini; D. Ramasamy

    2008-01-01

    The ethanol crude extract of stem bark of Holoptelea integrifolia Planch. traditionally used in Indian system of medicine was screened for its antioxidant activity using α-tocopherol as standard antioxidant. The free radical scavenging potential of the extract was evaluated by two different antioxidant methods; ferric thiocyanate and thiobarbituric acid method. The ethanol extract was found to exhibit good antioxidant property. Further physicochemical constants, elemental and heavy metal anal...

  20. Separations chemistry for f elements: Recent developments and historical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Nash, K.L. [Argonne National Lab., IL (United States); Choppin, G.R. [Florida State Univ., Tallahassee, FL (United States). Dept. of Chemistry

    1995-12-31

    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.

  1. Static calculation of the dynamic deflection elements for separation devices

    Directory of Open Access Journals (Sweden)

    Pavlenko I. V.

    2017-12-01

    Full Text Available The following paper considers the influence of acoustic oscillations on multiphase flows on their suspended particles, which can be destroyed or coagulated by vibrations. Considering this, the method of extension of application range of the dynamic separation element as vibrocoagulants due to the use of hydroaeroelasticity phenomena, namely flutter, has been proposed. There were considered the problems of development an engineering method for calculating dynamic separation elements, the main of which is the analytical solution of the hydroaeroelasticity problem. This work takes the first step to its development, considering the previous elastic elements deformation that has a significant effect on the flutter frequency. The state of their static equilibrium was conducted with the use of analytical dependencies of the finite element method. The bimodal finite elements with six degrees of freedom were used for dynamic deflection elements. As the result, there was determined the stiffness of pre-deformed plates and their maximum and minimum possible deflections. The functions of the median surface deflection in the form of a cubic polynomial were used in the model. In particular, there were considered the peculiarities of numerical modelling of coupled problems of gashydrodynamics flows and structural dynamics using the ANSYS Workbench, namely Fluent Flow and Transient Structural modules, which are combined with System Coupling. Also, the peculiarities of different approaches to multi-phase flow modelling are indicated. They are interesting not only by distribution of particles in the stream core, but also by the entrapped liquid film motion on the deposition surfaces.

  2. Neutron Star Mergers and Nucleosynthesis of Heavy Elements

    Science.gov (United States)

    Thielemann, F., -K.; Eichler, M.; Panov, I. V.; Wehmeyer, B.

    2017-11-01

    The existence of neutron star mergers has been supported since the discovery of the binary pulsar and the observation of its orbital energy loss, consistent with General Relativity. They are considered nucleosynthesis sites of the rapid neutron-capture process (r-process), which is responsible for creating approximately half of all heavy elements beyond Fe and is the only source of elements beyond Pb and Bi. Detailed nucleosynthesis calculations based on the decompression of neutron star matter are consistent with solar r-process abundances of heavy nuclei. Neutron star mergers have also been identified with short-duration {\\gamma}-ray bursts via their IR afterglow. The high neutron densities in ejected matter permit a violent r-process, leading to fission cycling of the heaviest nuclei in regions far from (nuclear) stability. Uncertainties in several nuclear properties affect the abundance distributions. The modeling of astrophysical events also depends on the hydrodynamic treatment, the occurrence of a neutrino wind after the merger and before the possible emergence of a black hole, and the properties of black hole accretion disks. We discuss the effect of nuclear and modeling uncertainties and conclude that binary compact mergers are probably a (or the) dominant site of the production of r-process nuclei in our Galaxy.

  3. Electrodialytic Separation of Phosphorus and Heavy Metals from Two Types of Sewage Sludge Ash

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie

    2014-01-01

    of P and heavy metals is required. The present work is an experimental screening of a new combination of acid extraction and electrodialysis–electrodialytic separation (EDS) for simultaneous P recovery and removal of heavy metals. Experiments were conducted with two different ashes; rich in Fe or Al......During sewage sludge incineration phosphorus (P) is retained in the ash in a form not directly available to plants. As P is a sparse resource, it is important to develop techniques for recovery of P from incinerated sewage sludge ashes (ISSA). Heavy metals are concentrated in ISSA and separation....... The separation method was best suited for the Fe-rich ash, where it was possible to separate P into one processing solution, heavy metals (Cu, Zn, Ni, Pb) into another, keeping the ash suspended in a third solution (which though still contained P after 1 week of EDS). For the Al rich ash, the separation...

  4. A novel method for the sequential removal and separation of multiple heavy metals from wastewater.

    Science.gov (United States)

    Fang, Li; Li, Liang; Qu, Zan; Xu, Haomiao; Xu, Jianfang; Yan, Naiqiang

    2018-01-15

    A novel method was developed and applied for the treatment of simulated wastewater containing multiple heavy metals. A sorbent of ZnS nanocrystals (NCs) was synthesized and showed extraordinary performance for the removal of Hg(2+), Cu(2+), Pb(2+) and Cd(2+). The removal efficiencies of Hg(2+), Cu(2+), Pb(2+) and Cd(2+) were 99.9%, 99.9%, 90.8% and 66.3%, respectively. Meanwhile, it was determined that solubility product (Ksp) of heavy metal sulfides was closely related to adsorption selectivity of various heavy metals on the sorbent. The removal efficiency of Hg(2+) was higher than that of Cd(2+), while the Ksp of HgS was lower than that of CdS. It indicated that preferential adsorption of heavy metals occurred when the Ksp of the heavy metal sulfide was lower. In addition, the differences in the Ksp of heavy metal sulfides allowed for the exchange of heavy metals, indicating the potential application for the sequential removal and separation of heavy metals from wastewater. According to the cumulative adsorption experimental results, multiple heavy metals were sequentially adsorbed and separated from the simulated wastewater in the order of the Ksp of their sulfides. This method holds the promise of sequentially removing and separating multiple heavy metals from wastewater. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Status of the low-energy super-heavy element facility at RIKEN

    Energy Technology Data Exchange (ETDEWEB)

    Schury, P., E-mail: schury@riken.jp [RIKEN, Nishina Center for Accelerator Based Science, Wako City, Saitama (Japan); Wada, M.; Ito, Y. [RIKEN, Nishina Center for Accelerator Based Science, Wako City, Saitama (Japan); Arai, F. [RIKEN, Nishina Center for Accelerator Based Science, Wako City, Saitama (Japan); Institute of Physics, University of Tsukuba, Tsukuba City, Ibaraki (Japan); Kaji, D. [RIKEN, Nishina Center for Accelerator Based Science, Wako City, Saitama (Japan); Kimura, S. [Institute of Physics, University of Tsukuba, Tsukuba City, Ibaraki (Japan); Morimoto, K.; Haba, H. [RIKEN, Nishina Center for Accelerator Based Science, Wako City, Saitama (Japan); Jeong, S. [Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Koura, H. [Advanced Science Research Center, Japan Atomic Energy Agency, Ibaraki 319-1195 (Japan); Miyatake, H. [Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Morita, K.; Reponen, M. [RIKEN, Nishina Center for Accelerator Based Science, Wako City, Saitama (Japan); Ozawa, A. [Institute of Physics, University of Tsukuba, Tsukuba City, Ibaraki (Japan); Sonoda, T.; Takamine, A. [RIKEN, Nishina Center for Accelerator Based Science, Wako City, Saitama (Japan); Wollnik, H. [Dept. Chemistry and BioChemistry, New Mexico State University, Las Cruces, NM (United States)

    2016-06-01

    In order to investigate nuclei produced via fusion–evaporation reactions, especially super-heavy elements (SHE), we have begun construction of a facility for conversion of fusion–evaporation residues (EVR) to low-energy beams. At the base of this facility is a small cryogenic gas cell utilizing a traveling wave RF-carpet, located directly following the gas-filled recoil ion separator GARIS-II, which will thermalize EVRs to convert them into ion beams amenable to ion trapping. We present here the results of initial studies of this small gas cell.

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

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, L.; Kaminski, M.; Bradley, C.; Buchholz, B.A.; Aase, S.B.; Tuazon, H.E.; Vandegrift, G.F. [Argonne National Lab., IL (United States); Landsberger, S. [Univ. of Illinois, Urbana, IL (United States)

    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.

  7. ST-LIBS for heavy element detection in complex matrices

    Science.gov (United States)

    Tamboli, M. M.; V. K., Unnikrishnan; Devangad, Praveen; K. M., Muhammed Shameem; Santhosh, C.

    2017-06-01

    Interest in the use of laser-based sensors operating in stand-off mode is increasing due to the wide range of options offered in the evaluation of distant targets. In this work, a stand-off laser induced breakdown spectroscopy (ST-LIBS) system has been developed and demonstrated to determine the heavy elements in soil samples. Initially, different parameters of the device have been optimized in ambient atmosphere and tested for quantitative analysis of Nickel and Chromium at two different stand-off distances (1 m and 6 m). The prepared concentrations were in the range of 100 ppm to 600 ppm. The laser energy of 150 mJ was maintained through out the experiment and to obtain a real time situation the target was in static state.

  8. Separation of heavy metal from water samples--The study of the synthesis of complex compounds of heavy metal with dithiocarbamates.

    Science.gov (United States)

    Kane, Sonila; Lazo, Pranvera; Ylli, Fatos; Stafilov, Trajce; Qarri, Flora; Marku, Elda

    2016-01-01

    The toxicity and persistence of heavy metal (HM) ions may cause several problems to marine organisms and human beings. For this reason, it is growing the interest in the chemistry of sulphur donor ligands such as dithiocarbamates (DDTC), due to their applications particularly in analytical chemistry sciences. The aim of this work has been the study of heavy metal complexes with DDTC and their application in separation techniques for the preconcentration and/or removing of heavy metals from the water solutions or the water ecosystems prior to their analysis. The HM-DDTC complexes were prepared and characterized by elemental analysis, FTIR and UV-Vis spectroscopic methods. The elemental analysis and the yield of the synthesis (97.5-99.9%) revealed a good purity of the complexes. High values of complex formation yields of HM-DDTC complexes is an important parameter for quantitatively removing/and or preconcentration of heavy metal ions from water solution even at low concentration of heavy metals. Significant differences founded between the characteristic parameters of UV/Vis (λmax and ϵmax) and FTIR absorption spectra of the parent DDTC and HM-DDTC complexes revealed the complex formation. The presence of the peaks at the visible spectral zone is important to M(nd(10-m))-L electron charge transfer of the new complexes. The (C=N) (1450-1500 cm(-1)) and the un-splitting (C-S) band (950-1002 cm(-1)) in HM-DDTC FTIR spectra are important to the identification of their bidentate mode (HM[S2CNC4H10]2). The total CHCl3 extraction of trace level heavy metals from water samples after their complex formation with DDTC is reported in this article.

  9. Spallation RI beam facility and heavy element nuclear chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Nagame, Yuichiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-11-01

    An outline of the spallation RI (Radioactive Ion) beam facility is presented. Neutron-rich nuclides are produced in the reaction of high intensity (10-1000 {mu}A) protons with energy of 1.5 GeV and an uranium carbide target. Produced nuclides are ionized in an isotope separator on-line (ISOL) and accelerated by the JAERI tandem and the booster linac. Current progress and a future project on the development of the RI beam facility are given. Studies of transactinide elements, including the synthesis of superheavy elements, nuclear structure far from stability, and RI-probed material science are planned with RI beams. An outlook of the transactinide nuclear chemistry studies using neutron-rich RI beams is described. (author)

  10. Electrodialytic treatment of sewage sludge ash for the recovery of phosphorous and separation of heavy metals

    DEFF Research Database (Denmark)

    Ebbers, Benjamin; Ottosen, Lisbeth M.; Jensen, Pernille Erland

    2012-01-01

    Mobilization and extraction of both phosphorus (P) and heavy metals (HM) from sewage sludge ash through means of acidification has been studied extensively. However, separation of both P and HM after mobilization to provide reusable materials has proven to be challenging. This study presents...... a combination of acidification and electrodialytic separation (EDS) to mobilize and separate P and HM from sewage sludge ash (SSA). The EDS experimental setup consists of three compartments, separated by ion exchange membranes which are located at either side of the stirred ash suspension. Through application...... in separation from the ash suspension to the anode compartment. Although 96% of the recovered P was mobilized, only 55% was separated from the ash suspension. Less mobilization (m), but better separation (s), from the ash and ash suspension was observed for heavy metals, 78% (m) 69% (s) for Cd; 24% (m) 7% (s...

  11. Review of even element super-heavy nuclei and search for element 120

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, S.; Heinz, S.; Mann, R.; Maurer, J.; Münzenberg, G.; Antalic, S.; Barth, W.; Burkhard, H. G.; Dahl, L.; Eberhardt, K.; Grzywacz, R.; Hamilton, J. H.; Henderson, R. A.; Kenneally, J. M.; Kindler, B.; Kojouharov, I.; Lang, R.; Lommel, B.; Miernik, K.; Miller, D.; Moody, K. J.; Morita, K.; Nishio, K.; Popeko, A. G.; Roberto, J. B.; Runke, J.; Rykaczewski, K. P.; Saro, S.; Scheidenberger, C.; Schött, H. J.; Shaughnessy, D. A.; Stoyer, M. A.; Thörle-Pospiech, P.; Tinschert, K.; Trautmann, N.; Uusitalo, J.; Yeremin, A. V.

    2016-06-01

    The reaction 54Cr$ + $248Cm was investigated at the velocity filter SHIP at GSI, Darmstadt, with the intention to study production and decay properties of isotopes of element 120. Three correlated signals were measured, which occurred within a period of 279ms. The heights of the signals correspond with the expectations for a decay sequence starting with an isotope of element 120. However, a complete decay chain cannot be established, since a signal from the implantation of the evaporation residue cannot be identified unambiguously. Measured properties of the event chain are discussed in detail. The result is compared with theoretical predictions. Previously measured decay properties of even element super-heavy nuclei were compiled in order to find arguments for an assignment from the systematics of experimental data. In the course of this review, a few tentatively assigned data could be corrected. New interpretations are given for results which could not be assigned definitely in previous studies. The discussion revealed that the cross-section for production of element 120 could be high enough so that a successful experiment seems possible with presently available techniques. However, a continuation of the experiment at SHIP for a necessary confirmation of the results obtained in a relatively short irradiation of five weeks is not possible at GSI presently. Therefore, we decided to publish the results of the measurement and of the review as they exist now. In the summary and outlook section we also present concepts for the continuation of research in the field of super-heavy nuclei.

  12. Review of even element super-heavy nuclei and search for element 120

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Goethe-Universitaet Frankfurt, Institut fuer Physik, Frankfurt (Germany); Heinz, S.; Mann, R.; Maurer, J.; Barth, W.; Burkhard, H.G.; Dahl, L.; Kindler, B.; Kojouharov, I.; Lang, R.; Lommel, B.; Runke, J.; Scheidenberger, C.; Schoett, H.J.; Tinschert, K. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Muenzenberg, G. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Manipal University, Manipal Centre for Natural Sciences, Manipal, Karnataka (India); Antalic, S.; Saro, S. [Comenius University, Department of Nuclear Physics and Biophysics, Bratislava (Slovakia); Eberhardt, K.; Thoerle-Pospiech, P.; Trautmann, N. [Johannes Gutenberg-Universitaet Mainz, Mainz (Germany); Grzywacz, R. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); University of Tennessee, Knoxville, TN (United States); Hamilton, J.H. [Vanderbuilt University, Department of Physics and Astronomy, Nashville, TN (United States); Henderson, R.A.; Kenneally, J.M.; Moody, K.J.; Shaughnessy, D.A.; Stoyer, M.A. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Miernik, K. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); University of Warsaw, Warsaw (Poland); Miller, D. [University of Tennessee, Knoxville, TN (United States); Morita, K. [RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama (Japan); Nishio, K. [Japan Atomic Energy Agency, Tokai, Ibaraki (Japan); Popeko, A.G.; Yeremin, A.V. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Roberto, J.B.; Rykaczewski, K.P. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Uusitalo, J. [University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland)

    2016-06-15

    The reaction {sup 54}Cr + {sup 248}Cm was investigated at the velocity filter SHIP at GSI, Darmstadt, with the intention to study production and decay properties of isotopes of element 120. Three correlated signals were measured, which occurred within a period of 279ms. The heights of the signals correspond with the expectations for a decay sequence starting with an isotope of element 120. However, a complete decay chain cannot be established, since a signal from the implantation of the evaporation residue cannot be identified unambiguously. Measured properties of the event chain are discussed in detail. The result is compared with theoretical predictions. Previously measured decay properties of even element super-heavy nuclei were compiled in order to find arguments for an assignment from the systematics of experimental data. In the course of this review, a few tentatively assigned data could be corrected. New interpretations are given for results which could not be assigned definitely in previous studies. The discussion revealed that the cross-section for production of element 120 could be high enough so that a successful experiment seems possible with presently available techniques. However, a continuation of the experiment at SHIP for a necessary confirmation of the results obtained in a relatively short irradiation of five weeks is not possible at GSI presently. Therefore, we decided to publish the results of the measurement and of the review as they exist now. In the summary and outlook section we also present concepts for the continuation of research in the field of super-heavy nuclei. (orig.)

  13. Heavy-Metal Fractions in Solid and Liquid Separates of Swine Slurry Separated using Different Technologies.

    Science.gov (United States)

    Olatuyi, S O; Kumaragamage, D; Akinremi, O O; Grieger, L

    2014-09-01

    Accumulation of metals is a concern with continuous application of swine slurry to agricultural soils. Solid-liquid separation is a promising approach for reducing phosphorus and total metal loadings with swine manure application to farmlands. However, very little work has been performed on the partitioning of different metal fractions in swine slurry to separated solids and liquids. This study examined the distribution of various metal fractions in raw manures (RM), their separated liquids (SL), and separated solids (SS). The three separation techniques used were centrifuge without flocculant (CNF), centrifuge with flocculant (CFL), and rotary press with flocculant (RFL). Concentrations of Cd, Cu, Zn, Ni, and Se in manure and separates were determined by a modified Sposito's sequential chemical fractionation scheme to extract water-soluble, exchangeable, organically bound, carbonate-precipitated, and residual fractions. The greatest concentrations of metals were recovered in the residual fraction, with the organically bound and carbonate-precipitated concentrations much greater than water-soluble and exchangeable fractions. Separation index () (i.e., percentage partitioned to SS) ranged from 13 to 66%, 9 to 87%, 16 to 93%, and 23 to 96% for water-soluble, exchangeable, organically bound, and carbonate-precipitated fractions, respectively. The values in general, were significantly ( < 0.05) greater for flocculant-based separation techniques than for CNF. For organically bound and carbonate-precipitated fractions, the greatest was obtained with the RFL for most metals. Our results suggest that applying the SL from RFL separation would minimize metal loading to farmlands compared with SL from CNF and CFL techniques. However, further validation is required using more sources of manure and different flocculants. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  14. Sources and speciation of heavy metals in municipal solid waste (MSW) and its effect on the separation technique

    Energy Technology Data Exchange (ETDEWEB)

    Biollaz, S.; Ludwig, Ch.; Stucki, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    A literature search was carried out to determine sources and speciation of heavy metals in MSW. A combination of thermal and mechanical separation techniques is necessary to achieve the required high degrees of metal separation. Metallic goods should be separated mechanically, chemically bound heavy metals by a thermal process. (author) 1 fig., 1 tab., 6 refs.

  15. The Zintl Chemistry of the Heavy Tetrel Elements

    Energy Technology Data Exchange (ETDEWEB)

    Klem, Michael Thomas [Iowa State Univ., Ames, IA (United States)

    2002-12-31

    Exploration of the alkali metal/alkaline-earth metal/heavy tetrel (Sn or Pb) systems has revealed a vast array of new chemistry and novel structure types. The structures and properties of these new materials have been studied in an attempt to understand the chemistry of these and other related systems. The first phase reported is Rb4Pb9 (K4Pb9 type). The compound contains two different types of Pb94- deltahedra, a monocapped square pyramid and a distorted tricapped trigonal prism. Both cluster geometries correspond to a nido assignment even though the tricapped trigonal prism is not the classic Wade's rules nido deltahedron expected for a monocapped square antiprism. Also, a series of compounds that contain square pyramidal Tt5 polyanions of tin and lead has been obtained in alkaline-earth or rare-earth metal-tetrel systems by direct fusion of the elements to yield Sr3Sn5, Ba3Pb5, and La3Sn5. These phases contain square pyramidal clusters of the tetrel elements that are weakly interlinked into chains via two types of longer intercluster interactions that are mediated by bridging cations and substantially influenced by cation size and the free electron count. Attempts at incorporating another main-group element to form heteroatomic clusters were also successful. In the case of A5InPb8 (A = K, Rb), the compounds contain clusters composed of two Pb4 tetrahedra that are interbridged by a lone μ6-In atom. The InPb8 units are weakly interlinked into sheets in the ab plane by long intercluster Pb-Pb interactions. Using As led to the formation of the compound K5As3Pb3 which is made up of As3Pb35- crown clusters that can be likened to a 6-atom hypho-cluster based on the tricapped trigonal parent as the closo

  16. Application of factor separation to heavy rainfall and cyclogenesis events: Mediterranean examples

    Science.gov (United States)

    Romero, R.

    2010-09-01

    The Mediterranean basin is an ideal atmospheric research "laboratory" recognized as one of the main cyclogenetic areas in the world. Much of the high impact weather affecting its coastal countries (notably strong winds and heavy precipitations) has been statistically associated with the near presence of a distinct cyclonic signature. The numerical modelling of these atmospheric circulations is the most powerful tool available to scientists to develop a better physical understanding of the responsible mechanisms. In particular, many studies have used this potential to isolate the role played by different physical factors by means of the factor separation technique. Boundary factors (e.g. orography and latent heat flux from the Mediterranean) and model physics factors (e.g. latent heat release in cloud systems) have been typically considered. Different results about the role of both types of factors in Mediterranean flash flood events will be shown and discussed. Comparatively less attention, however, has been paid to the effects due to internal features of the flow dynamics (jet streaks, troughs, fronts, etc) probably because, unlike the boundary of model physics factors, modifying or switching off these elements in the simulations is not straightforward. The three-dimensional nature and mutual dependence of pressure, temperature and wind fields pose serious constraints on the ways these fields can be altered without compromising the delicate dynamical balances that govern both the model equations and actual data. It will be presented a relatively clean approach to deal with these dynamical factors, based on the concept of potential vorticity (PV) and its invertibility principle. The role of upper-level precursor disturbances on heavy rain producing western Mediterranean cyclones will be studied by this PV inversion method. Finally, the applicability of the factor separation method to the study of extratropical cyclones in a framework which does not involve

  17. Stabilization and separation of heavy metals in incineration fly ash during the hydrothermal treatment process.

    Science.gov (United States)

    Hu, Yuyan; Zhang, Pengfei; Li, Jianping; Chen, Dezhen

    2015-12-15

    In the paper, hydrothermal treatment (HT) of MSWI fly ashes was performed to stabilize and separate heavy metals. Influences of pre-treatment, types of ferric and/or ferrous additives, and subsequent heavy metal stabilization procedure by adding phosphate were investigated. The chemical stability of hydrothermal products was examined by solid waste extraction procedure with acetic acid buffer solution. Mineralogical investigation of selected hydrothermal product was carried out by XRD. FEGE SEM- -EDX was used to study the morphology and surface compositions of the ash particles. Experimental results revealed that HT process facilitated heavy metal exposure to leaching solution. FEGE SEM-EDX images revealed that fly ash particles were re-organized during hydrothermal process and that the minerals with special shapes and containing high levels of heavy metals were formed. A mild acid washing treatment with final pH around 6.20 could remove soluble heavy metals. Therefore, it may be a proper pre- or post-treatment method for fly ash particles for the purpose of reducing heavy metal contents. For the purpose of stabilizing heavy metals, the addition of ferric/ferrous salts in the HT process or phosphate stabilization after HT is recommended. The HT process may be applied to realize the environmentally sound management of MSWI fly ash or to recover and utilize MSWI fly ash. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Process to separate transuranic elements from nuclear waste

    Science.gov (United States)

    Johnson, Terry R.; Ackerman, John P.; Tomczuk, Zygmunt; Fischer, Donald F.

    1989-01-01

    A process 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).

  19. Cold fusion of heavy ions paving the way to superheavy elements

    CERN Document Server

    Münzenberg, G

    2001-01-01

    Significant progress has been made approaching superheavy elements. A shell-stabilized region near hassium has been discovered. Element 112 has been synthesized. Recently evidence for the creation of elements 114, 116, and 118 has been reported. The way to these superheavy nuclei was paved by the cold fusion of heavy ions. In this paper experimental methods for heavy-element research, which is essentially physics with single atoms, are presented together with recent experimental results. The observed nuclear properties are discussed in the framework of theoretical models. New instrumental developments including accelerators and radioactive beams are be addressed.

  20. Heavy metals and essential elements in Italian cereals.

    Science.gov (United States)

    Brizio, P; Benedetto, A; Squadrone, S; Curcio, A; Pellegrino, M; Ferrero, M; Abete, M C

    2016-12-01

    Crops intended for human nutrition and food production containing different essential trace elements, such as copper and zinc, could be contaminated by toxic metals like cadmium and lead. The interrelationship between micronutrients and contaminant trace elements in different cereals was investigated in North-western Italy, where both agricultural and industrial activities are present. Elemental concentrations in sampled cereals were assessed by inductively coupled plasma mass spectrometry (ICP-MS). Rice, oats and barley reached the highest median levels for Al, Cd and Pb content, while corn samples were less contaminated by toxic metals. Regarding essential elements highest median values of Cu and Zn were both found in barley, while Ni median content was higher in oats. Rice had the lowest median levels of essential elements. The correlation study between toxic and essential elements seemed to demonstrate fixed trends in analysed samples, corroborating the importance of a different diet to limit potential adverse effects caused by toxic elements.

  1. 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.

  2. Process to separate transuranic elements from nuclear waste

    Science.gov (United States)

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

    1988-07-12

    A process 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.

  3. Chemistry of heavy- and trans-actinide elements. Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Tsukada, Kazuaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2000-03-01

    Experimental results on the chemical properties of the transactinide element, Rf (Z=104), on an atom-at-a-time base are reviewed. Status and future plans for the study of chemical behavior of transactinide elements with the JAERI tandem accelerator are reported. (author)

  4. In-beam fission study for Heavy Element Synthesis

    OpenAIRE

    Nishio Katsuhisa

    2013-01-01

    Fission fragment mass distributions were measured in heavy-ion induced fissions using 238U target nucleus. The measured mass distributions changed drastically with incident energy. The results are explained by a change of the ratio between fusion and qasifission with nuclear orientation. A calculation based on a fluctuation dissipation model reproduced the mass distributions and their incident energy dependence. Fusion probability was determined in the analysis. Evaporation residue cross sect...

  5. Heavy Ion Inertial Fusion Energy: Summaries of Program Elements

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, A; Barnard, J J; Kaganovich, I; Seidl, P A; Briggs, R J; Faltens, A; Kwan, J W; Lee, E P; Logan, B G

    2011-02-28

    The goal of the Heavy Ion Fusion (HIF) Program is to apply high-current accelerator technology to IFE power production. Ion beams of mass {approx}100 amu and kinetic energy {>=} 1 GeV provide efficient energy coupling into matter, and HIF enjoys R&D-supported favorable attributes of: (1) the driver, projected to be robust and efficient; see 'Heavy Ion Accelerator Drivers.'; (2) the targets, which span a continuum from full direct to full indirect drive (and perhaps fast ignition), and have metal exteriors that enable injection at {approx}10 Hz; see 'IFE Target Designs'; (3) the near-classical ion energy deposition in the targets; see 'Beam-Plasma Interactions'; (4) the magnetic final lens, robust against damage; see 'Final Optics-Heavy Ion Beams'; and (5) the fusion chamber, which may use neutronically-thick liquids; see 'Liquid-Wall Chambers.' Most studies of HIF power plants have assumed indirect drive and thick liquid wall protection, but other options are possible.

  6. TiO2/bone composite materials for the separation of heavy metal impurities from waste water solutions

    Science.gov (United States)

    Dakroury, G.; Labib, Sh.; Abou El-Nour, F. H.

    2012-09-01

    Pure bone material obtained from cow meat, as apatite-rich material, and TiO2-bone composite materials are prepared and studied to be used for heavy metal ions separation from waste water solutions. Meat wastes are chemically and thermally treated to control their microstructure in order to prepare the composite materials that fulfill all the requirements to be used as selective membranes with high performance, stability and mechanical strength. The prepared materials are analyzed using Hg-porosimetry for surface characterization, energy dispersive X-ray spectroscopy (EDAX) for elemental analysis and Fourier transform infrared spectroscopy (FTIR) for chemical composition investigation. Structural studies are performed using X-ray diffraction (XRD). Microstructural properties are studied using scanning electron microscopy (SEM) and specific surface area studies are performed using Brunauer-Emmet-Teller (BET) method. XRD studies show that multiphase structures are obtained as a result of 1h sintering at 700-1200 °C for both pure bone and TiO2-bone composite materials. The factors affecting the transport of different heavy metal ions through the selected membranes are determined from permeation flux measurements. It is found that membrane pore size, membrane surface roughness and membrane surface charge are the key parameters that control the transport or rejection of heavy metal ions through the selected membranes.

  7. Exploration of (super-)heavy elements using the Skyrme-Hartree-Fock model

    Energy Technology Data Exchange (ETDEWEB)

    Erler, Jochen

    2011-01-31

    Motivated by the steadily increasing number of known nuclei and nuclear properties, theories of nuclear structure are presently a field of intense research. This work concentrates on the self-consistent description of nuclei in terms of the Skyrme-Hartree-Fock (SHF) approach. The extrapolation of nuclear shell structure to the region of super-heavy elements (SHE) using the SHF model, the dependence on different parameterization and the influence of collective correlation will be studied. The general scope of this work are large scale calculation for a global survey of properties of SHE like binding energies, separation energies and decay characteristics and lifetimes. These calculations were done in a collaboration with the theory group of the GSI in Darmstadt and have the aim to develop a database of lifetimes and reaction rates for {alpha}, {beta}-decay and spontaneous fission in a very wide range with proton numbers 86 {<=} Z {<=} 120 and neutron numbers up to N {approx} 260 relevant for the astrophysical r-process. The results of this study for example predictions of a possible islands of very stable nuclei and information of favored decay mode for each nuclei are also applicable in the recent experimental synthesis of exotic SHE. For these calculation a framework to calculate {beta}-decay half-lives within the SHF model has been developed and the existing axial SHF code has been extended to compute {beta}-transition matrix elements and so to provide an estimation of half-lives. (orig.)

  8. Heavy element synthesis in the oldest stars and the early Universe.

    Science.gov (United States)

    Cowan, John J; Sneden, Christopher

    2006-04-27

    The first stars in the Universe were probably quite different from those born today. Composed almost entirely of hydrogen and helium (plus a tiny trace of lithium), they lacked the heavier elements that determine the formation and evolution of younger stars. Although we cannot observe the very first stars--they died long ago in supernovae explosions--they created heavy elements that were incorporated into the next generation. Here we describe how observations of heavy elements in the oldest surviving stars in our Galaxy's halo help us understand the nature of the first stars--those responsible for the chemical enrichment of our Galaxy and Universe.

  9. In-beam fission study for Heavy Element Synthesis

    Science.gov (United States)

    Nishio, Katsuhisa

    2013-12-01

    Fission fragment mass distributions were measured in heavy-ion induced fissions using 238U target nucleus. The measured mass distributions changed drastically with incident energy. The results are explained by a change of the ratio between fusion and qasifission with nuclear orientation. A calculation based on a fluctuation dissipation model reproduced the mass distributions and their incident energy dependence. Fusion probability was determined in the analysis. Evaporation residue cross sections were calculated with a statistical model in the reactions of 30Si + 238U and 34S + 238U using the obtained fusion probability in the entrance channel. The results agree with the measured cross sections for seaborgium and hassium isotopes.

  10. In-beam fission study for Heavy Element Synthesis

    Directory of Open Access Journals (Sweden)

    Nishio Katsuhisa

    2013-12-01

    Full Text Available Fission fragment mass distributions were measured in heavy-ion induced fissions using 238U target nucleus. The measured mass distributions changed drastically with incident energy. The results are explained by a change of the ratio between fusion and qasifission with nuclear orientation. A calculation based on a fluctuation dissipation model reproduced the mass distributions and their incident energy dependence. Fusion probability was determined in the analysis. Evaporation residue cross sections were calculated with a statistical model in the reactions of 30Si + 238U and 34S + 238U using the obtained fusion probability in the entrance channel. The results agree with the measured cross sections for seaborgium and hassium isotopes.

  11. CORONAL SOURCES, ELEMENTAL FRACTIONATION, AND RELEASE MECHANISMS OF HEAVY ION DROPOUTS IN THE SOLAR WIND

    Energy Technology Data Exchange (ETDEWEB)

    Weberg, Micah J. [PhD Candidate in Space Science, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2134A Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States); Lepri, Susan T. [Associate Professor, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2429 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States); Zurbuchen, Thomas H., E-mail: mjweberg@umich.edu, E-mail: slepri@umich.edu, E-mail: thomasz@umich.edu [Professor, Space Science and Aerospace Engineering, Associate Dean for Entrepreneurship Senior Counselor of Entrepreneurship Education, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2431 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States)

    2015-03-10

    The elemental abundances of heavy ions (masses larger than He) in the solar wind provide information about physical processes occurring in the corona. Additionally, the charge state distributions of these heavy ions are sensitive to the temperature profiles of their respective source regions in the corona. Heavy ion dropouts are a relatively new class of solar wind events identified by both elemental and ionic charge state distributions. We have shown that their origins lie in large, closed coronal loops where processes such as gravitational settling dominate and can cause a mass-dependent fractionation pattern. In this study we consider and attempt to answer three fundamental questions concerning heavy ion dropouts: (1) 'where are the source loops located in the large-scale corona?'; (2) 'how does the interplay between coronal processes influence the end elemental abundances?'; and (3) 'what are the most probable release mechanisms'? We begin by analyzing the temporal and spatial variability of heavy ion dropouts and their correlation with heliospheric plasma and magnetic structures. Next we investigate the ordering of the elements inside dropouts with respect to mass, ionic charge state, and first ionization potential. Finally, we discuss these results in the context of the prevailing solar wind theories and the processes they posit that may be responsible for the release of coronal plasma into interplanetary space.

  12. Microfluidic magnetic separator using an array of soft magnetic elements

    DEFF Research Database (Denmark)

    Smistrup, Kristian; Lund-Olesen, Torsten; Hansen, Mikkel Fougt

    2006-01-01

    We present the design, fabrication, characterization, and demonstration of a new passive magnetic bead separator. The device operates in an effective state when magnetized by an external magnetic field of only 50 mT, which is available from a tabletop electromagnet. We demonstrate the complete ca...

  13. Separation and recovery of heavy metals from waste water using synergistic solvent extraction

    Science.gov (United States)

    Li, Yan; Yang, Limei; Xu, Zheng; Sun, Qi

    2017-01-01

    Heavy metal wastewater pollution is one of the three major water pollutions in the world. The zinc hydrometallurgy smelting process usually discharge large quantities of heavy metal wastewater into the environment. In this paper, a synergistic solvent extraction process has been developed to recover copper, nickel, zinc and cadmium respectively from calcium and magnesium. The synergistic organic system contained 0.50 M Versatic 10 and 0.5 M Mextral 984H in DT100. Adjusting pH to 2.0 at 40 °C, the copper will be extracted preferentially with the extraction rate more than 99%. Continuing to adjust pH to 4.2 at 40 °C, the nickel will be extracted secondly with an extraction rate more than 98%; the zinc and cadmium in raffinate could be extracted separately while pH is about 6.5.

  14. 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)

  15. Development and testing of inorganic sorbents for radionuclide and heavy metal separations

    Energy Technology Data Exchange (ETDEWEB)

    Collins, J. [Oak Ridge National Lab., TN (United States)

    1996-10-01

    The objectives of this task are to develop, prepare, and test microspheres and granular forms of inorganic ion exchangers to remove radionuclides and heavy metals from waste streams occurring at various sites. Several inorganic materials, such as hexacyanoferrates, titanates, phosphates, and oxides have high selectivities and efficiencies for separating and removing radionuclides such as uranium, technetium, cesium and strontium, and metals such as cobalt, silver, zinc, and zirconium from aqueous waste streams. However, these sorvents frequently exist only as powders and consequently are not readily adaptable to continuous processing such as column chromatography.

  16. Separation of heavy metals: Removal from industrial wastewaters and contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Peters, R.W.; Shem, L.

    1993-03-01

    This paper reviews the applicable separation technologies relating to removal of heavy metals from solution and from soils in order to present the state-of-the-art in the field. Each technology is briefly described and typical operating conditions and technology performance are presented. Technologies described include chemical precipitation (including hydroxide, carbonate, or sulfide reagents), coagulation/flocculation, ion exchange, solvent extraction, extraction with chelating agents, complexation, electrochemical operation, cementation, membrane operations, evaporation, adsorption, solidification/stabilization, and vitrification. Several case histories are described, with a focus on waste reduction techniques and remediation of lead-contaminated soils. The paper concludes with a short discussion of important research needs in the field.

  17. Separation of heavy metals: Removal from industrial wastewaters and contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Peters, R.W.; Shem, L.

    1993-01-01

    This paper reviews the applicable separation technologies relating to removal of heavy metals from solution and from soils in order to present the state-of-the-art in the field. Each technology is briefly described and typical operating conditions and technology performance are presented. Technologies described include chemical precipitation (including hydroxide, carbonate, or sulfide reagents), coagulation/flocculation, ion exchange, solvent extraction, extraction with chelating agents, complexation, electrochemical operation, cementation, membrane operations, evaporation, adsorption, solidification/stabilization, and vitrification. Several case histories are described, with a focus on waste reduction techniques and remediation of lead-contaminated soils. The paper concludes with a short discussion of important research needs in the field.

  18. Survival and compound nucleus probability of super heavy element Z = 117

    Energy Technology Data Exchange (ETDEWEB)

    Manjunatha, H.C. [Government College for Women, Department of Physics, Kolar, Karnataka (India); Sridhar, K.N. [Government First grade College, Department of Physics, Kolar, Karnataka (India)

    2017-05-15

    As a part of a systematic study for predicting the most suitable projectile-target combinations for heavy-ion fusion experiments in the synthesis of {sup 289-297}Ts, we have calculated the transmission probability (T{sub l}), compound nucleus formation probabilities (P{sub CN}) and survival probability (P{sub sur}) of possible projectile-target combinations. We have also studied the fusion cross section, survival cross section and fission cross sections for different projectile-target combination of {sup 289-297}Ts. These theoretical parameters are required before the synthesis of the super heavy element. The calculated probabilities and cross sections show that the production of isotopes of the super heavy element with Z = 117 is strongly dependent on the reaction systems. The most probable reactions to synthetize the super heavy nuclei {sup 289-297}Ts are worked out and listed explicitly. We have also studied the variation of P{sub CN} and P{sub sur} with the mass number of projectile and target nuclei. This work is useful in the synthesis of the super heavy element Z = 117. (orig.)

  19. Comparative assessment of mineral elements and heavy metals accumulation in vegetable species

    Directory of Open Access Journals (Sweden)

    Nikolić Nataša P.

    2014-01-01

    Full Text Available The heavy metal (cadmium, lead, nickel, chromium and mineral element (potassium, phosphorus, calcium, magnesium levels in edible parts of tomato, potato, spinach, beetroot, parsley, parsnip, carrot, cauliflower, pepper and broccoli were determined by atomic absorption spectrophotometry. Six samples for each species originating from different localities were collected from green markets. The heavy metal concentrations ranged from calcium > phosphorus > magnesium. The highest mean levels of the heavy metals, as well as of potassium, calcium and magnesium, were found in spinach. A large number of samples containing high levels of toxic heavy metals, especially of cadmium and lead, impose the necessity for strict regulative guidelines concerning individual vegetable crops production, harvest, handling and storing, in order to diminish possibility of contamination.

  20. X-ray Ionization of Heavy Elements Applied to Protoplanetary Disks

    NARCIS (Netherlands)

    Ádámkovics, Máté; Glassgold, Alfred E.; Meijerink, Rowin

    The consequences of the Auger effect on the population of heavy-element ions are analyzed for the case of relatively cool gas irradiated by keV X-rays with intended applications to the accretion disks of young stellar objects. Highly charged ions are rapidly reduced to the doubly charged state in

  1. Chromatographic separation of heavy organic residues; TLC-FID: A useful monitoring tool

    Energy Technology Data Exchange (ETDEWEB)

    Weber, J.V. (Metz Univ., 57 (France). Lab. de Spectrometrie de Masse et Chimie Laser); Krzton, A. (Inst. of Coal Chemistry, Gliwice (Poland)); Cebolla, V. (CSIC, Inst. de Carboquimica, Zaragoza (Spain)); Swistek, M. (Metz Univ., 57 (France). Lab. de Spectrometrie de Masse et Chimie Laser)

    1993-11-01

    The determination of the relationships between the chemical composition and the thermal behaviour of heavy organic residues is of great importance considering their industrial applications. Due to the complexity of these products, a primary simplificative chromatographic step is generally needed. For this goal extrography is one of the most widely method used. Extrography combines extractive and chromatographic processes resulting in chemically selective separation. Nevertheless, preliminary experiments are often necessary to optimize the experimental conditions in order to reach the desired separation. Application of thin layer chromatography coupled with flame ionization detector (TLC-FID) to this objective seems evident but has not been yet described. In this work we discuss the use of TLC-FID to monitor the extrographic analysis of a binder coal tar pitch. (orig.)

  2. NEW HUBBLE SPACE TELESCOPE OBSERVATIONS OF HEAVY ELEMENTS IN FOUR METAL-POOR STARS

    Energy Technology Data Exchange (ETDEWEB)

    Roederer, Ian U.; Thompson, Ian B. [Carnegie Observatories, Pasadena, CA 91101 (United States); Lawler, James E. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Sobeck, Jennifer S. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Beers, Timothy C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Cowan, John J. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States); Frebel, Anna [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Ivans, Inese I. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Schatz, Hendrik [Department of Physics and Astronomy, Michigan State University, E. Lansing, MI 48824 (United States); Sneden, Christopher [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States)

    2012-12-15

    Elements heavier than the iron group are found in nearly all halo stars. A substantial number of these elements, key to understanding neutron-capture nucleosynthesis mechanisms, can only be detected in the near-ultraviolet. We report the results of an observing campaign using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope to study the detailed heavy-element abundance patterns in four metal-poor stars. We derive abundances or upper limits from 27 absorption lines of 15 elements produced by neutron-capture reactions, including seven elements (germanium, cadmium, tellurium, lutetium, osmium, platinum, and gold) that can only be detected in the near-ultraviolet. We also examine 202 heavy-element absorption lines in ground-based optical spectra obtained with the Magellan Inamori Kyocera Echelle Spectrograph on the Magellan-Clay Telescope at Las Campanas Observatory and the High Resolution Echelle Spectrometer on the Keck I Telescope on Mauna Kea. We have detected up to 34 elements heavier than zinc. The bulk of the heavy elements in these four stars are produced by r-process nucleosynthesis. These observations affirm earlier results suggesting that the tellurium found in metal-poor halo stars with moderate amounts of r-process material scales with the rare earth and third r-process peak elements. Cadmium often follows the abundances of the neighboring elements palladium and silver. We identify several sources of systematic uncertainty that must be considered when comparing these abundances with theoretical predictions. We also present new isotope shift and hyperfine structure component patterns for Lu II and Pb I lines of astrophysical interest.

  3. PROCESS FOR SEPARATING AMERICIUM AND CURIUM FROM RARE EARTH ELEMENTS

    Science.gov (United States)

    Baybarz, R.D.; Lloyd, M.H.

    1963-02-26

    This invention relates to methods of separating americium and curium values from rare earth values. In accordance with the invention americium, curium, and rare earth values are sorbed on an anion exchange resin. A major portion of the rare earth values are selectively stripped from the resin with a concentrated aqueous solution of lithium chloride, and americium, curium, and a minor portion of rare earth values are then stripped from the resin with a dilute aqueous solution of lithium chloride. The americium and curium values are further purified by increasing the concentration of lithium chloride in the solution to at least 8 molar and selectively extracting rare earth values from the resulting solution with a monoalkylphosphoric acid. (AEC)

  4. The effect of magnetite nanoparticles synthesis conditions on their ability to separate heavy metal ions

    Directory of Open Access Journals (Sweden)

    Bobik Magdalena

    2017-06-01

    Full Text Available Magnetite nanoparticles have become a promising material for scientific research. Among numerous technologies of their synthesis, co-precipitation seems to be the most convenient, less time-consuming and cheap method which produces fine and pure iron oxide particles applicable to environmental issues. The aim of the work was to investigate how the co-precipitation synthesis parameters, such as temperature and base volume, influence the magnetite nanoparticles ability to separate heavy metal ions. The synthesis were conducted at nine combinations of different ammonia volumes - 8 cm3, 10 cm3, 15 cm3 and temperatures - 30°C, 60°C, 90°C for each ammonia volume. Iron oxides synthesized at each combination were examined as an adsorbent of seven heavy metals: Cr(VI, Pb(II, Cr(III, Cu(II, Zn(II, Ni(II and Cd(II. The representative sample of magnetite was characterized using XRD, SEM and BET methods. It was observed that more effective sorbent for majority of ions was produced at 30°C using 10 cm3 of ammonia. The characterization of the sample produced at these reaction conditions indicate that pure magnetite with an average crystallite size of 23.2 nm was obtained (XRD, the nanosized crystallites in the sample were agglomerated (SEM and the specific surface area of the aggregates was estimated to be 55.64 m2·g-1 (BET. The general conclusion of the work is the evidence that magnetite nanoparticles have the ability to adsorb heavy metal ions from the aqueous solutions. The effectiveness of the process depends on many factors such as kind of heavy metal ion or the synthesis parameters of the sorbent.

  5. Separation and characterization of vanadium and nickel organometallic compounds in heavy crudes

    Energy Technology Data Exchange (ETDEWEB)

    Nali, M.; Corana, F.; Scilingo, A.; Scotti, R. (Eniricerche S.p.A., Milan (Italy))

    1994-01-01

    A new separation scheme has been developed to concentrate nickel and vanadium complexes in selected fractions before attempting a molecular characterization of these organometallic species in heavy crude oils. It involves a combination of solubility- (n-heptane deasphalting and pyridine/water extraction of asphaltenes) and polarity- (SO[sub 3]-modified silica gel column) based steps. The proposed method has been applied to Belayim crude oil. The nature of pyridine/water extract from asphaltenes has been investigated using both preparative gel permeation chromatography (GPC) and reverse phase liquid chromatography (RP-HPLC) combined (off-line) to graphite furnace atomic absorption (GFAA). The fractions obtained after the separation of the extract on a SO[sub 3]-modified silica gel column have been submitted to a series of analytical techniques. All the analytical evidence arising from the present study, indicates that vanadium, present in pyridine/water extract obtained from asphaltenes, is mostly bound in porphyrin structures, although the coordination sphere around vanadyl species, present in the most polar fraction obtained from the extract separation by column chromatography, shows different EPR parameter. On the other hand, nickel complexes are smaller and more polar than common Ni-porphyrins, which are concentrated in deasphalted oil. 16 refs., 9 figs., 2 tabs.

  6. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Mineralogy and heavy metal leachability of magnetic fractions separated from some Chinese coal fly ashes.

    Science.gov (United States)

    Lu, S G; Chen, Y Y; Shan, H D; Bai, S Q

    2009-09-30

    Magnetic fractions (MFs) in fly ashes from eight coal-burning power plants were extracted by magnetic separation procedure. Their mineralogy and potential leachability of heavy metals were analyzed using rock magnetism, X-ray diffraction (XRD), scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM/EDX) and leaching procedures (toxicity characteristics leaching procedure by the United States Environmental Protection Agency, TCLP, and gastric juice simulation test, GJST). Results show that the MFs in the fly ashes range between 2.2 and 16.3wt%, and are generally composed of magnetite, hematite, quartz and mullite. Thermomagnetic analysis and SEM/EDX indicate that the main magnetic carrier magnetite is substituted with small amounts of impure ions, and its structures are featured by rough, dendritic and granular iron spherules. The MFs are found to be rich in Fe, Mn, Cr, Cu, Cd and Pb. Compared with the non-magnetic fractions (NMFs), the MFs have about 5 times higher iron, and 1.6 times higher Mn, Cr, Cu and Cd concentrations. The TCLP test shows that the TCLP-extractable Cr, Cu, and Pb concentrations in the MFs are higher than those in the NMFs, while the TCLP-extractable Cd concentration in the MFs and NMFs is below the detection limit (Cr>Pb>Cd. The heavy metals of fly ashes have a great potential to be released into the environment under acid environment.

  9. Event-shape-engineering study of charge separation in heavy-ion collisions

    Science.gov (United States)

    Wen, Fufang; Bryon, Jacob; Wen, Liwen; Wang, Gang

    2018-01-01

    Recent measurements of charge-dependent azimuthal correlations in high-energy heavy-ion collisions have indicated charge-separation signals perpendicular to the reaction plane, and have been related to the chiral magnetic effect (CME). However, the correlation signal is contaminated with the background caused by the collective motion (flow) of the collision system, and an effective approach is needed to remove the flow background from the correlation. We present a method study with simplified Monte Carlo simulations and a multi-phase transport model, and develop a scheme to reveal the true CME signal via event-shape engineering with the flow vector of the particles of interest. Supported by a grant (DE-FG02-88ER40424) from U.S. Department of Energy, Office of Nuclear Physics

  10. Study of the Matrix Effect on the Plasma Characterization of Heavy Elements in Soil Sediments

    Directory of Open Access Journals (Sweden)

    Tawfik W.

    2007-01-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS has been applied to perform a study of the matrix effect on the plasma characterization of soil sediment targets. The plasma is generated by focusing a pulsed Nd: YAG laser on the target in air at atmospheric pressure. The plasma emission spectrum was detected using a portable Echelle spectrometer (Mechelle 7500 — Multichannel Instruments, Stockholm, Sweden with intensified CCD camera. Spectroscopic analysis of plasma evolution of laser produced plasmas has been characterized in terms of their spectra, and electron temperature. Four heavy elements V, Pb, Mn and Co were determined in the obtained spectra. The LTE and optically thin plasma conditions were verified for the produced plasma. The electron temperature and density were determined using the emission intensity and stark broadening, respectively, of the spectral lines of the heavy elements in the soil sediments. The electron temperature does not change with concentration. For environmental applications, the obtained results showed the capability of the proposed LIBS setup with the portable Mechelle 7500 spectrometer to be applied in-situ for real-time measurements of the variation of the matrix elemental composition of soil sediments by following up only a single element as a marker for the composition of the soil sediment without need of analysis of the other elements.

  11. Electro-kinetic Separation of Rare Earth Elements Using a Redox-Active Ligand.

    Science.gov (United States)

    Fang, Huayi; Cole, Bren E; Qiao, Yusen; Bogart, Justin A; Cheisson, Thibault; Manor, Brian C; Carroll, Patrick J; Schelter, Eric J

    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))C6 H4 CH2 }3 N]3- . Using this method, a single-step separation factor up to 261 was obtained for the separation of a 50:50 yttrium-lutetium mixture. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. 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)

  13. Orthotropic node-separation finite element method for composite laminate in hypervelocity impact simulation

    Science.gov (United States)

    Zhang, Xiaotian; Liu, Tao; Qiu, Xinming

    2017-11-01

    This paper reports a finite element modeling approach to simulate the hypervelocity impact (HVI) response of composite laminate. Node-separation finite element (NSFE) method based on scalar-element-fracture technique for isotropic material in HVI simulation has been presented in the previous study. To extend NSFE to composite materials, an orthotropic node-separation finite element (ONSFE) method is developed. This approach employs an orthotropic continuum material model and a corresponding orthotropic-element-fracture technique to represent the HVI behavior/damage of composite laminate. A series of HVI simulations are conducted and the developed ONSFE method is validated by comparing with the experimental data. The simulation results show that ONSFE can successfully capture the HVI phenomena of composite laminate, such as the orthotropic property, nonlinear shock response, perforation, fiber breakage and delamination. Finally, a HVI event of Whipple shield is simulated and the computational capability of ONSFE for predicting the damage state of the composite bumper is further evaluated.

  14. Trace elements and heavy metals in hair of stage III breast cancer patients.

    Science.gov (United States)

    Benderli Cihan, Yasemin; Sözen, Selim; Oztürk Yıldırım, Sema

    2011-12-01

    This prospective study was designed to compare the hair levels of 36 elements in 52 patients with stage III breast cancer to those of an equal number of healthy individuals. Principal component and cluster analysis were used for source of identification and apportionment of heavy metals and trace elements in these two groups. A higher average level of iron was found in samples from patients while controls had higher levels of calcium. Both patients and controls had elevated levels of tin, magnesium, zinc, and sodium. Almost all element values in cancer patients showed higher dispersion and asymmetry than in healthy controls. Between the two groups, there were statistically significant differences in the concentrations of silver, arsenic, gold, boron, barium, beryllium, calcium, cadmium, cerium, cobalt, cesium, gadolinium, manganese, nickel, lead, antimony, scandium, selenium, and zinc (p cancer group and between palladium and cobalt (r = 0.945) in the healthy individuals. Our results show that there are distinct patterns of heavy metals and trace elements in the hair of breast cancer patients in comparison to healthy controls. These results could be of significance in the diagnosis of breast cancer.

  15. The TRUSPEAK Concept: Combining CMPO and HDEHP for Separating Trivalent Lanthanides from the Transuranic Elements

    Energy Technology Data Exchange (ETDEWEB)

    Lumetta, Gregg J.; Gelis, Artem V.; Braley, Jenifer C.; Carter, Jennifer C.; Pittman, Jonathan W.; Warner, Marvin G.; Vandegrift, George F.

    2013-04-08

    Combining octyl(phenyl)-N,N-diisobutyl-carbamoylmethyl-phosphine oxide (CMPO) and bis-(2-ethylhexyl) phosphoric acid (HDEHP) into a single process solvent for separating transuranic elements from liquid high-level waste is explored. Co-extraction of americium and the lanthanide elements from nitric acid solution is possible with a solvent mixture consisting of 0.1-M CMPO plus 1-M HDEHP in n-dodecane. Switching the aqueous-phase chemistry to a citrate-buffered solution of diethylene triamine pentaacetic acid (DTPA) allows for selective stripping of americium, separating it from the lanthanide elements. Potential strategies for managing molybdenum and zirconium (both of which co-extract with americium and the lanthanides) have been developed. The work presented here demonstrates the feasibility of combining CMPO and HDEHP into a single extraction solvent for recovering americium from high-level waste and its separation from the lanthanides.

  16. Exploring Ultra-Heavy Cosmic Rays with the Trans-Iron Galactic Element Recorder (TIGER)

    Science.gov (United States)

    Link, Jason; Supertiger Collaboration

    2017-01-01

    Elements heavier than iron are primarily synthesized by neutron capture. These elements can be accelerated as cosmic-rays and measuring their abundances at Earth can yield information about galactic cosmic-rays' sources, the acceleration processes and the composition of the universe beyond the boundaries of our solar system. The Trans-Iron Galactic Element Recorder (TIGER) and its larger successor SuperTIGER was designed to measure the abundance of these ultra-heavy cosmic rays between Z=10 and Z=60. These detectors utilize scintillators with a wavelength shifter bar and PMT readout system as well as aerogel and acrylic Cherenkov detectors to identify the charge and energy of a particle and utilize a scintillating fiber hodoscope to provide trajectory information. In this talk I will review the results from this highly successful program, give the status for the next SuperTIGER flight planned for a December 2017 launch from Antarctica, and discuss the future direction of the program.

  17. 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.

  18. Contamination and Health Risks from Heavy Metals (Cd and Pb and Trace Elements (Cu and Zn in Dairy Products

    Directory of Open Access Journals (Sweden)

    Hamid Reza Ghafari

    2017-08-01

    Conclusion: Considering the serious contamination of some brands of butter and cheese by Cu and Pb, a control of heavy metals and trace elements levels during the whole production processing of dairy products must be applied.

  19. Comparison of two different electrodialytic cells for separation of phosphorus and heavy metals from sewage sludge ash

    DEFF Research Database (Denmark)

    Ebbers, Benjamin; Ottosen, Lisbeth M.; Jensen, Pernille Erland

    2015-01-01

    With decreasing availability of phosphorus from primary resources its recovery from waste streams becomes increasingly more important. Sewage sludge ash is rich in phosphorus, but the direct use as fertilizer is limited because of inorganic contaminants such as heavy metals and strong bonding...... utilizing a three compartment cell setup where the anode, cathode and stirred suspension are separated by ion exchange membranes are reported. Simplifying this experimental setup by removing the anion exchange membrane brings the anode in direct contact with the stirred ash suspension. Through...... this adjustment, half-reactions at the anode contribute to the acidity of the stirred suspension resulting in increased dissolution of both phosphorus and heavy metals (Cd, Cu, Cr, Pb, Zn, Ni) and better separation of most heavy metals from the stirred ash suspension. When the ash is suspended in an acidic...

  20. Seismic monitoring of heavy oil reservoirs: Rock physics and finite element modelling

    Science.gov (United States)

    Theune, Ulrich

    In the past decades, remote monitoring of subsurface processes has attracted increasing attention in geophysics. With repeated geophysical surveys one attempts to detect changes in the physical properties in the underground without directly accessing the earth. This technique has been proven to be very valuable for monitoring enhanced oil recovery programs. This thesis presents an modelling approach for the feasibility analysis for monitoring of a thermal enhanced oil recovery technique applied to heavy oil reservoirs in the Western Canadian Sedimentary Basin. In order to produce heavy oil from shallow reservoirs thermal oil recovery techniques such as the Steam Assisted Gravity Drainage (SAGD) are often employed. As these techniques are expensive and technically challenging, early detection of operational problems is without doubt of great value. However, the feasibility of geophysical monitoring depends on many factors such as the changes in the rock physical properties of the target reservoir. In order to access the feasibility of seismic monitoring for heavy oil reservoirs, a fluid-substitutional rock physical study has been carried out to simulate the steam injection. The second modelling approach is based on a modified finite element algorithm to simulate the propagation of elastic waves in the earth, which has been developed independently in the framework of this thesis. The work summarized in this thesis shows a possibility to access the feasibility of seismic monitoring for heavy oil reservoirs through an extensive rock-physical study. Seismic monitoring is a useful tool in reservoir management decision process. However, the work reported here suggests that seismic monitoring of SAGD processes in the heavy oil reservoirs of the Western Canadian Sedimentary Basin is only feasible in shallow, unconsolidated deposits. For deeper, but otherwise geological similar reservoirs, the SAGD does not create a sufficient change in the rock physical properties to be

  1. Assessment of heavy metals exposure, noise and thermal safety in the ambiance of a vacuum metallurgy separation system for recycling heavy metals from crushed e-wastes.

    Science.gov (United States)

    Zhan, Lu; Xu, Zhenming

    2014-12-01

    Vacuum metallurgy separation (VMS) is a technically feasible method to recover Pb, Cd and other heavy metals from crushed e-wastes. To further determine the environmental impacts and safety of this method, heavy metals exposure, noise and thermal safety in the ambiance of a vacuum metallurgy separation system are evaluated in this article. The mass concentrations of total suspended particulate (TSP) and PM10 are 0.1503 and 0.0973 mg m(-3) near the facilities. The concentrations of Pb, Cd and Sn in TSP samples are 0.0104, 0.1283 and 0.0961 μg m(-3), respectively. Health risk assessments show that the hazard index of Pb is 3.25 × 10(-1) and that of Cd is 1.09 × 10(-1). Carcinogenic risk of Cd through inhalation is 1.08 × 10(-5). The values of the hazard index and risk indicate that Pb and Cd will not cause non-cancerous effects or carcinogenic risk on workers. The noise sources are mainly the mechanical vacuum pump and the water cooling pump. Both of them have the noise levels below 80 dB (A). The thermal safety assessment shows that the temperatures of the vacuum metallurgy separation system surface are all below 303 K after adopting the circulated water cooling and heat insulation measures. This study provides the environmental information of the vacuum metallurgy separation system, which is of assistance to promote the industrialisation of vacuum metallurgy separation for recovering heavy metals from e-wastes. © The Author(s) 2014.

  2. Long-lived heavy mass elements half-lives (A > 125)

    Energy Technology Data Exchange (ETDEWEB)

    Holden, N.E.

    1985-01-01

    Reported values of half-lives of intermediate mass and heavy elements are evaluated. The evaluation analysis estimates the systematic error the resulting standard deviation. Recommended values are then presented for /sup 128/Te, /sup 130/Te, /sup 129/I, /sup 138/La, /sup 144/Nd, /sup 145/Nd, /sup 146,147,148/Sm, /sup 152/Gd, /sup 154/Dy, /sup 176/Lu, /sup 174/Hf, /sup 180/Ta, /sup 187/Re, /sup 186/Os, /sup 190/Pt, /sup 204,205/Pb, and /sup 230,232/Th. 103 refs., 21 tabs. (WRF)

  3. X-ray Ionization of Heavy Elements Applied to Protoplanetary Disks

    OpenAIRE

    Ádámkovics, Máté; Glassgold, Alfred E.; Meijerink, Rowin

    2011-01-01

    The consequences of the Auger effect on the population of heavy element ions are analyzed for the case of relatively cool gas irradiated by keV X-rays, with intended applications to the accretion disks of young stellar ob jects. Highly charged ions are rapidly reduced to the doubly-charged state in neutral gas, so the aim here is to derive the production rates for these singly- and doubly-charged ions and to specify their transformation by recombination, charge transfer, and molecular reactio...

  4. Evaluation of a 2-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.; Röckmann, 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 O2. The main

  5. A Taxonomy for Heavy-Duty Telemanipulation Tasks Using Elemental Actions

    Directory of Open Access Journals (Sweden)

    Alexander Owen-Hill

    2013-10-01

    Full Text Available In the maintenance of large scientific facilities, telemanipulation procedures can involve various subprocedures which in turn are made up of a sequence of subtasks. This work presents a taxonomy which describes a set of elemental actions for heavy-duty telemanipulation, along with an example of these actions in a standard maintenance subprocedure. As maintenance tasks are often very different at high-level, this generalized way of deconstructing tasks allows a highly adaptable approach to describe the sequence of any procedure, which can then be used for such applications as task monitoring, automation or detection of incomplete tasks. We describe in detail the properties of each elemental action and apply the taxonomy to an example subprocedure to show how the process can be generalizable. An automatic state-machine creation stage is shown, which would be used at the task scheduling stage to simplify calculations carried out during the moment-by-moment execution of the task.

  6. CE-XRF-initial steps toward a non-invasive elemental sensitive detector for liquid separations.

    Science.gov (United States)

    Tyssebotn, Inger Marie Bergø; Fittschen, Andreas; Fittschen, Ursula Elisabeth Adriane

    2017-11-29

    The toxicity, bioavailability, and mobilization of elements within the biosphere is dependent on its species. CE has emerged as a strong separation technique for elemental speciation. Conventionally, CE has been coupled with UV-vis, C 4 D, PIXE (proton-induced X-ray emission), and ICP-MS. UV-vis and C 4 D are not elemental sensitive detection methods, PIXE requires the etching of the detection window resulting in a very brittle capillary, and ICP-MS is an expensive large footprint instrument. Here, we aim to develop an elemental specific detector, XRF (X-ray fluorescence spectrometry), for use with CE. A custom-built micro-XRF was tested and static LODs were determined for 19 elements (Ca-U) with both unmodified (20-926 ppm) and modified capillaries (20-291 ppm). A custom-built CE was combined with the micro-XRF and separation of Ca 2+ and Co 2+ was obtained. Sr 2+ coeluted with Ca 2+ in the mixture, but because of the elemental sensitivity of XRF, the Sr and Ca signals could be separated. After successful testing of the micro-XRF, the feasibility of using a low-cost X-ray source and detector was tested. Even lower LODs were obtained for Ga and Rb, showing the feasibility of a smaller, low-cost XRF unit as an elemental specific detector. However, the buffer selection that can be conveniently used with XRF is currently limited due to capillary corrosion, likely correlated to radiolysis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Heavy metals and trace elements in atmospheric fall-out: Their relationship with topsoil and wheat element composition

    Energy Technology Data Exchange (ETDEWEB)

    Bermudez, Gonzalo M.A., E-mail: gbermudez@com.uncor.edu [Instituto Multidisciplinario de Biologia Vegetal (IMBIV), CONICET (Argentina); Catedra de Quimica General, FCEFyN, Universidad Nacional de Cordoba, Avda. Velez Sarsfield 1611, Ciudad Universitaria (X5016 GCA), Cordoba (Argentina); Jasan, Raquel; Pla, Rita [Tecnicas Analiticas Nucleares, Comision Nacional de Energia Atomica (CAE), Presbitero Gonzalez y Aragon N Degree-Sign 15 (B1802AYA), Ezeiza (Argentina); Pignata, Maria L. [Instituto Multidisciplinario de Biologia Vegetal (IMBIV), CONICET (Argentina); Catedra de Quimica General, FCEFyN, Universidad Nacional de Cordoba, Avda. Velez Sarsfield 1611, Ciudad Universitaria (X5016 GCA), Cordoba (Argentina)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer Metal and trace element deposition rates and concentrations in bulk samples. Black-Right-Pointing-Pointer Anthropogenic vs. natural sources were identified using enrichment factors and PCA. Black-Right-Pointing-Pointer Anthropogenic sources for Ca, Cd, Cu, Fe, Mn, Ni, Pb, Sb, U, Zn and lanthanides. Black-Right-Pointing-Pointer Main sources were a cement plant, chemical-mechanical industries, cities and mining. Black-Right-Pointing-Pointer Metals in wheat grain were predicted by soil and bulk deposition composition. - Abstract: The objectives of this study were to determine the average concentrations and deposition rates of 28 elements in atmospheric bulk deposition and to elucidate associations among topsoil, bulk deposition and wheat element composition. The fluxes of arsenic (As), copper (Cu), lead (Pb) and zinc (Zn) deposition in Cordoba were higher than in other agro-ecosystems, which reflects both natural (geochemistry and topsoil removal) and anthropogenic sources. High lanthanide, uranium (U) and thorium (Th) concentrations revealed the impact of an open cast uranium mine. The highest enrichment factors (EF) were those of Cu, Pb, Zn and nickel (Ni), with calcium (Ca) being the most prominent in the surroundings of a cement plant. Industries and the transport of airborne urban pollutants were the main anthropogenic sources for Ca, Cu, Ni, Pb, Zn, cadmium (Cd), iron (Fe), manganese (Mn) and antimony (Sb). The concentrations of metals in wheat grain were predicted using the topsoil and atmospheric fall-out composition with R{sup 2} = 0.90, with the latter being the best explanatory variable. The present study highlights the potential health hazards of wheat consumption (Environmental Protection Agency) by the assessment of heavy metals in bulk atmospheric deposition.

  8. Helioseismic models of the sun with a low heavy element abundance

    Science.gov (United States)

    Ayukov, S. V.; Baturin, V. A.

    2017-10-01

    Helioseismology and neutrino experiments probing the internal structure of the Sun have yieldedmuch information, such as the adiabatic elasticity index, density, and sound speed in the convective and radiative zones, the depth of the convective zone, and the flux of neutrinos from the core. The standard model of the Sun does not adequately reproduce these characteristics, with models with low heavy element contents (mass fraction of metals Z = 0.013 in the convective zone) deviating from the helioseismic data appreciably more strongly than models with high heavy element contents ( Z = 0.018). However, a spectroscopic low Z value is supported by studies reconstructing the Γ 1 profile in the adiabatic part of the convective zone based on the oscillation frequencies. Models of the convective zone show a good agreement precisely for low Z values. This study attempts to construct a model for the Sun with low Z that satisfies the helioseismic constraints. This model requires changes in the p + p reaction cross section and the opacities in the radiative zone. In our view, the helioseismic result for the mass concentrated in the convective zone testifies that the p + p reaction cross section or the electron-screening coefficient in the solar core must be increased by several percent over the current values. This requires a comparatively small correction to the opacities (by less than 5%), in order to obtain a solar model with low Z that is in agreement with the results of helioseismology and the observed solar neutrino fluxes.

  9. Heavy Metals and Biogenic Elements in Aquatic Systems of the Don River Delta

    Science.gov (United States)

    Tkachenko, Anna; Tkachenko, Oleg

    2014-05-01

    River deltas are located in the lower parts of the cascade landscape-geochemical systems of the river basins, so their geochemical conditions often characterize the anthropogenic impact on whole river system. The Don River runs through the one of the most agriculturally developed and densely populated area of Russia, and flows into the Azov Sea - the smallest and shallowest sea in the world. These factors determine the geochemical features of aquatic systems of the Don River mouth area and the specificity of the "river-sea" geochemical barrier zone. The paper presents results of the field studies of the geochemical structure of the Don River mouth area, which were conducted in frames of the RFBR project in 2012-2013. Major types of the deltaic water streams and bodies were studied in different hydrological seasons: spring floods, summer, autumn and winter low water periods. About 50 samples of water, suspended matter and 60 samples of bottom sediments have been collected and analyzed for heavy metals (Fe, Mn, Zn, Cu, Ni, Co, Pb, Cr, Cd etc.) and biogenic elements (nitrate, nitrite, ammonium, phosphates, silica, total nitrogen and phosphorus, dissolved oxygen and chlorophyll) content. To assess the toxicity degree and nutrient potential of water, bioassay test conducted by growing daphnia in water samples were held. The study shows that the Don River delta water is characterized by the relatively low values of dissolved heavy metal content. Significantly higher values of heavy metals were determined in the vicinity of settlements only. Metal accumulation in bottom sediments can be associated mainly with the rate of water flow. Higher values were found in sediments of small channels with weak flow velocity and prevailing processes of the suspended matter deposition. The data on the seasonal dynamics of nutrients and spatial variability of their forms have been obtained. The maximum concentration of nitrogen, phosphorus, silicon, and other biogenic elements are

  10. 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.

  11. Optimization of a dual capture element magnetic separator for the purification of high velocity water flow

    Science.gov (United States)

    Belounis, Abdallah; Mehasni, Rabia; Ouili, Mehdi; Feliachi, Mouloud; El-Hadi Latreche, Mohamed

    2016-02-01

    In this paper a magnetic separator based on the use of a cascade arrangement of two identical capture elements has been optimized and verified. Such a separator is intended for the separation of fine particles of iron from flowing water at high velocity. The optimization has concerned the search for the excitation current and the distance between the capture elements that permit the extraction of the particles from a water flow in a circular channel at an average velocity ufav = 1.05 m/s. For such optimization we have minimized the objective function that is the distance between the capture position of a particle initially situated at a specific position and the central point of the last capture element of the arrangement. To perform the minimization, we have applied the Tabu search method. To validate the obtained results experimental verification based on the control of the evolution of the captured particle buildup and the quantifying of the separated volume of particles was achieved. Contribution to the topical issue "Numelec 2015 - Elected submissions", edited by Adel Razek

  12. Mercury and trace element distribution in density separates of a South African Highveld (#4) coal: Implications for mercury reduction and preparation of export coal

    Science.gov (United States)

    Kolker, Allan; Senior, Connie L.; van Alphen, Chris; Koenig, Alan E.; Geboy, Nicholas J.

    2017-01-01

    Eight density separates of Permian Highveld (#4) coal were investigated for partitioning of Hg and trace elements. The separates include float fractions obtained in heavy media having densities of 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0 g/cm3, and the sink fraction for 2.0 g/cm3. Bulk analysis of the separates shows strong (R2 ≥ 0.80) positive correlations between pyritic sulfur and mercury, and between ash yield and both pyritic sulfur and mercury. Laser ablation (LA) ICP-MS analysis of individual pyrite grains in the separates confirms association of Hg and As with pyrite as indicated by bulk analysis. Other elements detected in pyrite by LA-ICP-MS include Mn, Co, Ni, Tl, and Pb. Results for the separates allow prediction of Hg, trace elements, and ash yields expected in specific South African coal products. These range from 0.06 ppm Hg and an ash yield of 11.5% ash for the export fraction to 0.47 ppm Hg and an ash yield of 60.9% for the discard (stone) fraction (dry basis). Results show pronounced differences expected between coal used for domestic power generation and coal which is exported.

  13. Separating homogeneous and inhomogeneous line widths of heavy- and light-hole excitons in weakly disordered semiconductor quantum wells.

    Science.gov (United States)

    Bristow, Alan D; Zhang, Tianhao; Siemens, Mark E; Cundiff, Steven T; Mirin, R P

    2011-05-12

    Optical two-dimensional Fourier-transform spectroscopy is used to study the heavy- and light-hole excitonic resonances in weakly disordered GaAs quantum wells. Homogeneous and inhomogeneous broadening contribute differently to the two-dimensional resonance line shapes, allowing separation of homogeneous and inhomogeneous line widths. The heavy-hole exciton exhibits more inhomogeneous than homogeneous broadening, whereas the light-hole exciton shows the reverse. This situation occurs because of the interplay between the length scale of the disorder and the exciton Bohr radius, which affects the exciton localization and scattering. Utilizing this separation of line widths, excitation-density-dependent measurements reveal that many-body interactions alter the homogeneous dephasing, while disorder-induced dephasing is unchanged.

  14. Heavy element accumulation in Evernia prunastri lichen transplants around a municipal solid waste landfill in central Italy.

    Science.gov (United States)

    Nannoni, Francesco; Santolini, Riccardo; Protano, Giuseppe

    2015-09-01

    This paper presents the results of a biomonitoring study to evaluate the environmental impact of airborne emissions from a municipal solid waste landfill in central Italy. Concentrations of 11 heavy elements, as well as photosynthetic efficiency and cell membrane integrity were measured in Evernia prunastri lichens transplanted for 4months in 17 monitoring sites around the waste landfill. Heavy element contents were also determined in surface soils. Analytical data indicated that emissions from the landfill affected Cd, Co, Cr, Cu, Ni, Pb, Sb and Zn concentrations in lichens transplanted within the landfill and along the fallout direction. In these sites moderate to severe accumulation of these heavy elements in lichens was coupled with an increase in cell membrane damage and decrease in photosynthetic efficiency. Nevertheless, results indicated that landfill emissions had no relevant impact on lichens, as heavy element accumulation and weak stress symptoms were detected only in lichen transplants from sites close to solid waste. The appropriate management of this landfill poses a low risk of environmental contamination by heavy elements. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Design of three-phase gravity separators for heavy oils; Projeto de separadores trifasicos para oleos pesados

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Rosivania P.; Bannwart, Antonio C. [Universidade Estadual de Campinas, SP (Brazil); Carvalho, Carlos H.M. de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    The primary processing of crude oil consists in the separation of oil, gas, water (and solids suspensions, if present), the conditioning of the hydrocarbons for transportation to the refinery, and the water treatment for re-use. With the discovery of significant fields of heavy oil in Brazil, whose densities are close to the density of water and viscosities are about hundreds to thousand times higher than the viscosity of water, the production and primary processing of this fluid with usual technology is not attractive and often unfeasible. It is well known that the demand from the majority of the refineries is that the quantity of water dispersion in the oil (BSW) is below 1%, so this work investigates the behavior of the water dispersion in heavy oil, causing an increase in viscosity and density. Therefore, this work intends to define strategies to efficiently separate these liquids, emphasizing the physical aspects of separation. Mathematica software was used for the equation modeling, which governs the horizontal separation vases dimensioning, allowing the observation of the influence of many variables on the separator dimensions. (author)

  16. Ionization potentials of the lanthanides and actinides - towards atomic spectroscopy of super-heavy elements

    Science.gov (United States)

    Wendt, K.; Gottwald, T.; Mattolat, C.; Raeder, S.

    2014-06-01

    A study on the systematic of the atomic ionization potentials for both, the lanthanide and actinide elements have been performed. The existing experimental basis, predominantly relying on results from resonance ionization spectroscopy, has been extended by novel laser spectroscopic investigations on the elements Au, Dy, Pr and Pa. Conclusive results of suitable precision for the ionization potentials could be obtained except for Pa, due to the complexity of its atomic spectrum. Nevertheless, a consistent interpretation of the observed trends for the ionization potentials of lanthanides and actinides was attempted. The series of lanthanides depicts the two well-known, completely smooth, linear trends above and below half-shell closure, from which an expectation value for the missing ionization potential of the all radioactive element promethium of IP Pm= 44985(140) cm -1 was derived. In contrast, the lighter members of the actinide series below the half-filled shell exhibit a significant deviation from predictions, which are ascribed dominantly to relativistic influences affecting the energetic position of the multitude of low-lying configurations. With the assumption of removal of a 6d electron during the ionization process agreement between theory and experiment and a smooth, even though not linear behavior, is obtained also in this region of the Periodic Table. This new interpretation could help to better predict similar trends and systematics for elements heavier than the actinides. Particularly relevant in this respect are the super-heavy elements, which are produced only in minuscule atom numbers and thus were not accessible for any atomic physics study yet.

  17. Combining CMPO and HEH[EHP] for Separating Trivalent Lanthanides from the Transuranic Elements

    Energy Technology Data Exchange (ETDEWEB)

    Braley, Jenifer C.; Lumetta, Gregg J.; Carter, Jennifer C.

    2013-09-05

    Combining octyl(phenyl)-N,N-diisobutyl-carbamoylmethylphosphine oxide (CMPO) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) into a single process solvent for separating transuranic elements from liquid high-level waste is explored. The lanthanides and americium can be co-extracted from HNO3 into 0.2 mol/L CMPO + 1.0 mol/L HEH[EHP] in n-dodecane. The extraction is relatively insensitive to the HNO3 concentration within 0.1 to 5 mol/L HNO3. Americium can be selectively stripped from the CMPO/HEH[EHP] solvent into a citrate-buffered N-(2-hydroxyethyl)ethylenediaminetriacetic acid solution . Separation factors >14 can be achieved in the range pH 2.5 to 3.7, and the separation factors are relatively insensitive to pH, a major advantage of this solvent formulation.

  18. New water soluble phosphonate and polycarboxylate complexants for enhanced f element separations

    Energy Technology Data Exchange (ETDEWEB)

    Nash, K.L.; Rickert, P.G.; Lessmann, E.P.; Mendoza, M.D.; Feil, J.F.; Sullivan, J.C.

    1994-08-01

    While lipophilic extractant molecules and ion exchange polymeric materials are clearly essential to efficient separation of metal ions by solvent extraction or ion exchange, the most difficult separations often could not be accomplished without the use of water soluble complexants. This report focuses on recent developments in design, synthesis and characterization of phosphonic acid and polycarboxylic acid ligands for enhanced f element separations. Emphasis is on the basic solution chemistry and crystal structures of complexes of the f elements with selected amino-derivatives of methanediphosphonic acid and with tetrahydrofuran-2,3,4,5-tetracarboxylic acid. The former series of compounds exhibit high affinity for lanthanides and actinides in acidic solutions. The latter ligand exhibits an unusual (and very useful) ``anti-selectivity`` for uranyl ion in a solvent extraction process, which permits efficient separation of uranyl from more radioactive components of nuclear wastes. Most of the observed effects can be explained through examination of the structure of the ligand, and comparison of the spectroscopic and thermodynamic parameters for complexation of various metal ions.

  19. 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.

  20. Trace Elements, Heavy Metals and Vitamin Levels in Patients with Coronary Artery Disease

    Science.gov (United States)

    Cebi, Aysegul; Kaya, Yuksel; Gungor, Hasan; Demir, Halit; Yoruk, Ibrahim Hakki; Soylemez, Nihat; Gunes, Yilmaz; Tuncer, Mustafa

    2011-01-01

    Aim: In the present study, we aimed to assess serum concentrations of zinc (Zn), copper (Cu), iron (Fe), cadmium (Cd), lead (Pb), manganese (Mn), vitamins A (retinol), D (cholecalciferol) and E (α-tocopherol) in patients with coronary artery disease (CAD) and to compare with healthy controls. Methods: A total of 30 CAD patients and 20 healthy subjects were included in this study. Atomic absorption spectrophotometry (UNICAM-929) was used to measure heavy metal and trace element concentrations. Serum α-tocopherol, retinol and cholecalciferol were measured simultaneously by high performance liquid chromatography (HPLC). Results: Demographic and baseline clinical characteristics were not statistically different between the groups. Serum concentrations of retinol (0.3521±0.1319 vs. 0.4313±0.0465 mmol/I, p=0.013), tocopherol (3.8630±1.3117 vs. 6.9124±1.0577 mmol/I, ptrace elements and vitamins may be changed in patients with CAD. In this relatively small study we found that serum levels of retinol, tocopherol, cholecalciferol, iron and copper may be lower whereas serum lead concentrations may be increased in patients with CAD. PMID:21850195

  1. Synthesis of superheavy elements at the Dubna gas-filled recoil separator

    Energy Technology Data Exchange (ETDEWEB)

    Voinov, A. A., E-mail: voinov@jinr.ru [Joint Institute for Nuclear Research (Russian Federation); Collaboration: JINR (Dubna), LLNL (Livermore), ORNL (Oak Ridge), University of Tennessee (Knoxville), Vanderbilt University (Nashville), Research Institute of Atomic Reactors (Dimitrovgrad) Collaboration

    2016-12-15

    A survey of experiments at the Dubna gas-filled recoil separator (Laboratory of Nuclear Reactions, JINR, Dubna) aimed at the detection and study of the “island of stability” of superheavy nuclei produced in complete fusion reactions of {sup 48}Ca ions and {sup 238}U–{sup 249}Cf target nuclei is given. The problems of synthesis of superheavy nuclei, methods for their identification, and investigation of their decay properties, including the results of recent experiments at other separators (SHIP, BGS, TASCA) and chemical setups, are discussed. The studied properties of the new nuclei, the isotopes of elements 112–118, as well as the properties of their decay products, indicate substantial growth of stability of the heaviest nuclei with increasing number of neutrons in the nucleus as the magic number of neutrons N = 184 is approached.

  2. Ion-exchange separation of the rare earth elements by means of solution of ammonium phthalate and chloride

    Energy Technology Data Exchange (ETDEWEB)

    Hubicki, W.; Ozga, W. (Uniwersytet Marii Curie-Sklodowskiej, Lublin (Poland))

    1976-01-01

    A new method of ion exchange separation of lanthanons by the use of equimolar solution of ammonium phthalate and ammonium chloride as an eluent was elaborated. This method allows to separate light lanthanons and to obtain concentrate of samarium and heavy lanthanons. 99.99% Y/sub 2/O/sub 3/ was obtained from non-neodymium concentration with 47.4% efficiency. The influence of change in concentration and pH of eluent on the effectiveness of separation was examined. It was found that an increase in concentration of eluent and pH leads to quick separation of yttrium from samarium and heavy lanthanons. However, the efficiency of pure Y/sub 2/O/sub 3/ decreases distinctly.

  3. Filament-strung stand-off elements for maintaining pane separation in vacuum insulating glazing units

    Science.gov (United States)

    Bettger, Kenneth J; Stark, David H

    2013-08-20

    A vacuum insulating glazing unit (VIGU) comprises first and second panes of transparent material, first and second anchors, a plurality of filaments, a plurality of stand-off elements, and seals. The first and second panes of transparent material have edges and inner and outer faces, are disposed with their inner faces substantially opposing one another, and are separated by a gap having a predetermined height. The first and second anchors are disposed at opposite edges of one pane of the VIGU. Each filament is attached at one end to the first anchor and at the other end to the second anchor, and the filaments are collectively disposed between the panes substantially parallel to one another. The stand-off elements are affixed to each filament at predetermined positions along the filament, and have a height substantially equal to the predetermined height of the gap such that the each stand-off element touches the inner surfaces of both panes. The seals are disposed about the edges of the panes, enclosing the stand-off elements within a volume between the panes from which the atmosphere may be evacuated to form a partial vacuum.

  4. Multi-element analysis of manganese nodules by atomic absorption spectrometry without chemical separation

    Science.gov (United States)

    Kane, J.S.; Harnly, J.M.

    1982-01-01

    Five manganese nodules, including the USGS reference nodules A-1 and P-1, were analyzed for Co, Cu, Fe, K, Mg, Mn, Na, Ni and Zn without prior chemical separation by using a simultaneous multi-element atomic absorption spectrometer with an air-cetylene flame. The nodules were prepared in three digestion matrices. One of these solutions was measured using sixteen different combinations of burner height and air/acetylene ratios. Results for A-1 and P-1 are compared to recommended values and results for all nodules are compared to those obtained with an inductively coupled plasma. The elements Co, Cu, Fe, K, Mg, Mn, Na, Ni, and Zn are simultaneously determined with a composite recovery for all elements of 100 ?? 7%, independent of the digestion matrices, heights in the flame, or flame stoichiometries examined. Individual recoveries for Co, K, and Ni are considerably poorer in two digests than this composite figure, however. The optimum individual recoveries of 100 ?? 5% and imprecisions of 1-4%, except for zinc, are obtained when Co, K, Mn, Na and Ni are determined simultaneously in a concentrated digest, and in another analytical sequence, when Cu, Fe, Mg, Mn and Zn are measured simultaneously after dilution. Determination of manganese is equally accurate in the two sequences; its measurement in both assures internal consistency between the two measurement sequences. This approach improves analytical efficiency over that for conventional atomic absorption methods, while minimizing loss of accuracy or precision for individual elements. ?? 1982.

  5. Serum heavy metal and antioxidant element levels of children with recurrent wheezing.

    Science.gov (United States)

    Razi, C H; Akin, O; Harmanci, K; Akin, B; Renda, R

    2011-01-01

    The aim of the study is to investigate the levels of toxic heavy metals related with environmental pollution and trace elements involved in antioxidant system in children suffering from recurrent wheezing. One hundred children with recurrent wheezing (at least three recurrences) between the ages from 1 to 6 years took part in the study, and also 116 age- and sex- matched healthy children were involved in the study as a control group. Venous blood samples were collected and serum mercury, lead, aluminium, zinc, selenium, and copper levels were studied using ICP-MS. Serum lead (0.76±0.15 vs. 0.27±0.01, p:0.001) and mercury levels (1.31±0.15 vs 0.71±0.05, p115.6±1.87 vs. 125.4±2.94, p:0.008) levels were lower in wheezy group than those acquired from the control group. Serum zinc levels were found to be correlated with number of ARTIs (r(p):-0.332, p:0.001) and the number of wheezy attacks (r(p):-0.776, p<0.001) during the previous year in the wheezy group. Elevated levels of serum lead and mercury and low levels of zinc and selenium may suggest some disturbances in the antioxidant system in children with recurrent wheezing. This means that children with recurrent wheezing are much more susceptible to environmental pollutants and respiratory tract infections than healthy children and this heavy metal-antioxidant relationship may play a role as a contributing factor in the pathogenesis of recurrent wheezing in children. Copyright © 2009 SEICAP. Published by Elsevier Espana. All rights reserved.

  6. Heavy metal and trace elements in riparian vegetation and macrophytes associated with lacustrine systems in Northern Patagonia Andean Range.

    Science.gov (United States)

    Juárez, Andrea; Arribére, María A; Arcagni, Marina; Williams, Natalia; Rizzo, Andrea; Ribeiro Guevara, Sergio

    2016-09-01

    Vegetation associated with lacustrine systems in Northern Patagonia was studied for heavy metal and trace element contents, regarding their elemental contribution to these aquatic ecosystems. The research focused on native species and exotic vascular plant Salix spp. potential for absorbing heavy metals and trace elements. The native species studied were riparian Amomyrtus luma, Austrocedrus chilensis, Chusquea culeou, Desfontainia fulgens, Escallonia rubra, Gaultheria mucronata, Lomatia hirsuta, Luma apiculata, Maytenus boaria, Myrceugenia exsucca, Nothofagus antarctica, Nothofagus dombeyi, Schinus patagonicus, and Weinmannia trichosperma, and macrophytes Hydrocotyle chamaemorus, Isöetes chubutiana, Galium sp., Myriophyllum quitense, Nitella sp. (algae), Potamogeton linguatus, Ranunculus sp., and Schoenoplectus californicus. Fresh leaves were analyzed as well as leaves decomposing within the aquatic bodies, collected from lakes Futalaufquen and Rivadavia (Los Alerces National Park), and lakes Moreno and Nahuel Huapi (Nahuel Huapi National Park). The elements studied were heavy metals Ag, As, Cd, Hg, and U, major elements Ca, K, and Fe, and trace elements Ba, Br, Co, Cr, Cs, Hf, Na, Rb, Se, Sr, and Zn. Geochemical tracers La and Sm were also determined to evaluate contamination of the biological tissues by geological particulate (sediment, soil, dust) and to implement concentration corrections.

  7. Trace elements and heavy metals in the Grand Bay National Estuarine Reserve in the northern Gulf of Mexico

    Science.gov (United States)

    The Grand Bay National Estuarine Research Reserve has the highest biotic diversity of habitats and offer a reserve of food resources and commercially significant species. Rapid human civilization has led to accumulation of heavy metals and trace elements in estuaries. The Grand Bay National Estuarin...

  8. Heavy Metals and Trace Elements Atmospheric Deposition Studies in Tula Region Using Moss Biomonitors Technique

    CERN Document Server

    Ermakova, E V; Steinnes, E

    2002-01-01

    For the first time the moss biomonitors technique was used in air pollution studies in Tula Region (Central Russia), applying NAA, AAS. Moss samples were collected at 83 sites in accordance with the sampling strategy adopted in European projects on biomonitoring atmospheric deposition. A wide set of trace elements in mosses was determined. The method of epithermal neutron activation at IBR-2 reactor of FLNP JINR has made it possible to identify 33 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Tb, Yb, Hf, Ta, W, Th, U) in the large-scale concentration range - from 10000 ppm for K to 0,001 ppm for Tb and Ta. Cu, Cd and Pb were determined by the flame AAS in the Norwegian Institute of Science and Technology. Using the graphical technique and principal component analysis allowed to separate plant, crustal and general pollution components in the moss. The obtained data will be used for constructing coloured maps of the distribution of elements over t...

  9. Chromatographic Separation of Heavy Metal Cations on a Silica Gel-G with Amino Acid

    Directory of Open Access Journals (Sweden)

    S. M. Wanjari

    2012-01-01

    Full Text Available Thin layer chromatographic method has been developed for the separation of metal ions such as Cr(VI, Cr(III, As(III, Cd(II, Tl(III and Hg(II from their two, three and four component mixtures. The separations were performed on thin layer of silica gel ‘G’ using aqueous l-Alanine as mobile phase. The effect of concentration and pH of mobile phase on the Rf values of individual metal ions were studied and the optimum conditions for separation of metal ions from their mixture were determined.

  10. 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).

  11. Separation method of heavy-ion particle image from gamma-ray mixed images using an imaging plate

    CERN Document Server

    Yamadera, A; Ohuchi, H; Nakamura, T; Fukumura, A

    1999-01-01

    We have developed a separation method of alpha-ray and gamma-ray images using the imaging plate (IP). The IP from which the first image was read out by an image reader was annealed at 50 deg. C for 2 h in a drying oven and the second image was read out by the image reader. It was found out that an annealing ratio, k, which is defined as a ratio of the photo-stimulated luminescence (PSL) density at the first measurement to that at the second measurement, was different for alpha rays and gamma rays. By subtracting the second image multiplied by a factor of k from the first image, the alpha-ray image was separated from the alpha and gamma-ray mixed images. This method was applied to identify the images of helium, carbon and neon particles of high energies using the heavy-ion medical accelerator, HIMAC. (author)

  12. Origin of the heavy elements in binary neutron-star mergers from a gravitational-wave event

    Science.gov (United States)

    Kasen, Daniel; Metzger, Brian; Barnes, Jennifer; Quataert, Eliot; Ramirez-Ruiz, Enrico

    2017-11-01

    The cosmic origin of elements heavier than iron has long been uncertain. Theoretical modelling shows that the matter that is expelled in the violent merger of two neutron stars can assemble into heavy elements such as gold and platinum in a process known as rapid neutron capture (r-process) nucleosynthesis. The radioactive decay of isotopes of the heavy elements is predicted to power a distinctive thermal glow (a ‘kilonova’). The discovery of an electromagnetic counterpart to the gravitational-wave source GW170817 represents the first opportunity to detect and scrutinize a sample of freshly synthesized r-process elements. Here we report models that predict the electromagnetic emission of kilonovae in detail and enable the mass, velocity and composition of ejecta to be derived from observations. We compare the models to the optical and infrared radiation associated with the GW170817 event to argue that the observed source is a kilonova. We infer the presence of two distinct components of ejecta, one composed primarily of light (atomic mass number less than 140) and one of heavy (atomic mass number greater than 140) r-process elements. The ejected mass and a merger rate inferred from GW170817 imply that such mergers are a dominant mode of r-process production in the Universe.

  13. Origin of the heavy elements in binary neutron-star mergers from a gravitational-wave event.

    Science.gov (United States)

    Kasen, Daniel; Metzger, Brian; Barnes, Jennifer; Quataert, Eliot; Ramirez-Ruiz, Enrico

    2017-11-02

    The cosmic origin of elements heavier than iron has long been uncertain. Theoretical modelling shows that the matter that is expelled in the violent merger of two neutron stars can assemble into heavy elements such as gold and platinum in a process known as rapid neutron capture (r-process) nucleosynthesis. The radioactive decay of isotopes of the heavy elements is predicted to power a distinctive thermal glow (a 'kilonova'). The discovery of an electromagnetic counterpart to the gravitational-wave source GW170817 represents the first opportunity to detect and scrutinize a sample of freshly synthesized r-process elements. Here we report models that predict the electromagnetic emission of kilonovae in detail and enable the mass, velocity and composition of ejecta to be derived from observations. We compare the models to the optical and infrared radiation associated with the GW170817 event to argue that the observed source is a kilonova. We infer the presence of two distinct components of ejecta, one composed primarily of light (atomic mass number less than 140) and one of heavy (atomic mass number greater than 140) r-process elements. The ejected mass and a merger rate inferred from GW170817 imply that such mergers are a dominant mode of r-process production in the Universe.

  14. Effects of heavy metal and other elemental additives to activated sludge on growth of Eisenia foetida

    Energy Technology Data Exchange (ETDEWEB)

    Hartenstein, R. (State Univ. of New York, Syracuse); Neuhauser, E.F.; Narahara, A.

    1981-09-01

    The approximate level at which added concentrations of certain elements would cause an activated sludge to induce a toxic effect upon the growth of Eisenia foetida was determined. During 43 trials on sludge samples obtained throughout 1 year of study, earthworms grew from 3 to 10 mg live wt at hatching to 792 mg +- 18% (mean +- C.V.) in 8 weeks, when sludge was 24/sup 0/C and contained no additives. None of several elements commonly used in microbial growth media enhanced the growth rate of the earthworm. At salt concentrations up to about 6.6% on a dry wt basis, none of six anions tested was in and of itself toxic, while five of 15 cations - Co, Hg, Cu, Ni, and Cd - appeared specifically to inhibit growth rate or cause death. Manganese, Cr, and Pb were innocuous even at the highest levels of application - 22,000, 46,000, and 52,000 mg/kg, respectively. Neither the anionic nor cationic component of certain salts, such as NaCl or NH/sub 4/Cl, could be said to inhibit growth, which occurred only at high concentrations of these salts (about 3.3 and/or 6.6%). Below 7 mmho/cm, toxicity could not be correlated with electrolytic conductance, though higher values may help to explain the nonspecific growth inhibitory effects of salts like NaCl and KCl. Nor could toxicity ever be ascribed to hydrogen ion activity, since sludge pH was not altered even at the highest salt dose. It is concluded that except under very extreme conditions, the levels of heavy metals and salts generally found in activated sludges will not have an adverse affect on the growth of E. foetida.

  15. Swift heavy ion induced nano-dimensional phase separation in liquid immiscible binary Mn-Bi

    Science.gov (United States)

    Srivastava, S. K.; Khan, S. A.; Sudheer Babu, P.; Avasthi, D. K.

    2014-08-01

    Pulsed laser deposited 60 nm thin film of homogeneous Mn0.82Bi0.18 composite has been irradiated by 100 MeV Au ions at fluence 1 × 1013 ions/cm2, and investigated by field emission scanning electron microscopy, X-ray diffraction, magnetic hysteresis, X-ray photoelectron spectroscopy, and nanoindentation measurements. Dispersed nanostructures of soft Bi-rich phase of about 20 nm diameter emerged in a hard Mn-rich matrix on irradiation. Such structures, as synthesized by the present novel swift heavy ion irradiation approach, are usable as self-lubricating thin films.

  16. Swift heavy ion induced nano-dimensional phase separation in liquid immiscible binary Mn–Bi

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.K., E-mail: sanjeev@phy.iitkgp.ernet.in [Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur 721302 (India); Khan, S.A. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, P.O. Box 10502, New Delhi 110067 (India); Sudheer Babu, P. [Department of Physics, RGUKT, Nuzvid 521201 (India); Avasthi, D.K. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, P.O. Box 10502, New Delhi 110067 (India)

    2014-08-01

    Pulsed laser deposited 60 nm thin film of homogeneous Mn{sub 0.82}Bi{sub 0.18} composite has been irradiated by 100 MeV Au ions at fluence 1 × 10{sup 13} ions/cm{sup 2}, and investigated by field emission scanning electron microscopy, X-ray diffraction, magnetic hysteresis, X-ray photoelectron spectroscopy, and nanoindentation measurements. Dispersed nanostructures of soft Bi-rich phase of about 20 nm diameter emerged in a hard Mn-rich matrix on irradiation. Such structures, as synthesized by the present novel swift heavy ion irradiation approach, are usable as self-lubricating thin films.

  17. Marine phosphorites as potential resources for heavy rare earth elements and yttrium

    Science.gov (United States)

    Hein, James; Koschinsky, Andrea; Mikesell, Mariah; Mizell, Kira; Glenn, Craig R.; Wood, Ray

    2016-01-01

    Marine phosphorites are known to concentrate rare earth elements and yttrium (REY) during early diagenetic formation. Much of the REY data available are decades old and incomplete, and there has not been a systematic study of REY distributions in marine phosphorite deposits that formed over a range of oceanic environments. Consequently, we initiated this study to determine if marine phosphorite deposits found in the global ocean host REY concentrations of high enough grade to be of economic interest. This paper addresses continental-margin (CM) and open-ocean seamount phosphorites. All 75 samples analyzed are composed predominantly of carbonate fluorapatite and minor detrital and authigenic minerals. CM phosphorites have low total REY contents (mean 161 ppm) and high heavy REY (HREY) complements (mean 49%), while seamount phosphorites have 4–6 times higher individual REY contents (except for Ce, which is subequal; mean ΣREY 727 ppm), and very high HREY complements (mean 60%). The predominant causes of higher concentrations and larger HREY complements in seamount phosphorites compared to CM phosphorites are age, changes in seawater REY concentrations over time, water depth of formation, changes in pH and complexing ligands, and differences in organic carbon content in the depositional environments. Potential ore deposits with high HREY complements, like the marine phosphorites analyzed here, could help supply the HREY needed for high-tech and green-tech applications without creating an oversupply of the LREY.

  18. Marine Phosphorites as Potential Resources for Heavy Rare Earth Elements and Yttrium

    Directory of Open Access Journals (Sweden)

    James R. Hein

    2016-08-01

    Full Text Available Marine phosphorites are known to concentrate rare earth elements and yttrium (REY during early diagenetic formation. Much of the REY data available are decades old and incomplete, and there has not been a systematic study of REY distributions in marine phosphorite deposits that formed over a range of oceanic environments. Consequently, we initiated this study to determine if marine phosphorite deposits found in the global ocean host REY concentrations of high enough grade to be of economic interest. This paper addresses continental-margin (CM and open-ocean seamount phosphorites. All 75 samples analyzed are composed predominantly of carbonate fluorapatite and minor detrital and authigenic minerals. CM phosphorites have low total REY contents (mean 161 ppm and high heavy REY (HREY complements (mean 49%, while seamount phosphorites have 4–6 times higher individual REY contents (except for Ce, which is subequal; mean ΣREY 727 ppm, and very high HREY complements (mean 60%. The predominant causes of higher concentrations and larger HREY complements in seamount phosphorites compared to CM phosphorites are age, changes in seawater REY concentrations over time, water depth of formation, changes in pH and complexing ligands, and differences in organic carbon content in the depositional environments. Potential ore deposits with high HREY complements, like the marine phosphorites analyzed here, could help supply the HREY needed for high-tech and green-tech applications without creating an oversupply of the LREY.

  19. Heavy-ion radiation induces both activation of multiple endogenous transposable elements and alterations in DNA methylation in rice

    Science.gov (United States)

    Zhang, Meng; Sun, Yeqing; Li, Xishan; Xiaolin, Cui; Li, Xiang

    2012-07-01

    Space radiation represents a complex environmental condition in which several interacting factors such as electron, neutron, proton, heavy-ion are involved, which may provoke stress responses and jeopardize genome integrity. Given the inherent property of epigenetic modifications to respond to intrinsic aswell as external perturbations, it is conceivable that epigenetic markers like DNA methylation and transposition may undergo alterations in response to space radiation. Cytosine DNA methylation plays important roles in maintaining genome stability and controlling gene expression. A predominant means for Transposable elements (TEs) to cause genetic instability is via their transpositional activation. To find the detailed molecular characterization of the nature of genomic changes induced by space radiation, the seeds of rice were exposed to 0.02, 0.2, 1, 2 and 20 Gy dose of ^{12}C heavy-ion radiation, respectively. We found that extensive alteration in both DNA methylation and gene expression occurred in rice plants after different dose of heavy-ion radiation. Here we shown that heavy-ion radiation has induced transposition of mPing and Tos17 in rice, which belong to distinct classes including the miniature inverted terminal repeat TEs (MITEs) and long-terminal repeat (LTR) retrotransposons, respectively. mPing and Tos17 mobility were found to correlate with cytosine methylation alteration detected by MSAP and genetic variation detected by AFLP. The result showed that at least in some cases transposition of TEs was associated with cytosine demethylation within the elements. Our results implicate that the heavy-ion radiation represents a potent mutagenic agent that can cause genomic instabilities by eliciting transposition of endogenous TEs in rice. Keywords: Heavy-ion radiation, DNA methylation, Transposable elements, mPing, Tos17

  20. Five heavy metallic elements and age-related macular degeneration: Korean National Health and Nutrition Examination Survey, 2008-2011.

    Science.gov (United States)

    Park, Sang Jun; Lee, Ju Hyun; Woo, Se Joon; Kang, Se Woong; Park, Kyu Hyung

    2015-01-01

    To investigate the association between age-related macular degeneration (AMD) and 5 heavy metallic elements (lead, mercury, cadmium, manganese, and zinc). A cross-sectional study using a complex, stratified, multistage, probability cluster survey. Participants of the Korean National Health and Nutrition Examination Survey from 2008 to 2011. Using a standardized protocol, AMD was determined by fundus photograph grading. Blood concentrations of lead, mercury, cadmium, manganese, and zinc were measured. Associations between AMD and these 5 elements were estimated using logistic regression analyses (LRAs). The distributions of the 5 metallic elements in blood were analyzed, and the same set of LRAs estimating the association between AMD and logarithmic-transformed blood concentrations of the 5 elements were also conducted. Association between AMD and 5 heavy metals. Lead was positively associated with both early AMD and late AMD in all LRAs. Mercury and cadmium also had a positive association with late AMD in all LRAs, but not with early AMD. In contrast, manganese and zinc had an inverse association with late AMD in all LRAs. Manganese and zinc were not associated with early AMD. Using logarithmic-transformed blood concentrations for each metallic element, the LRAs showed similar results compared with those of the LRAs using nontransformed blood concentrations, despite the skewed distribution of these metallic elements in the blood. This study suggests that the toxic heavy metals (lead, mercury, and cadmium) may negatively influence late AMD, whereas essential heavy metals (manganese and zinc) may favorably influence late AMD. Lead may widely affect the pathogenesis of both early and late AMD. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  1. Separation of protein and lactose intake over meals dissociates postprandial glucose and insulin concentrations and reduces postprandial insulin responses in heavy veal calves

    NARCIS (Netherlands)

    Vicari, T.; Borne, van den J.J.G.C.; Gerrits, W.J.J.; Zbinden, Y.; Blum, J.W.

    2008-01-01

    The present study examined, at identical daily nutrient intakes, the impact of separating protein and lactose intakes across two daily meals on the metabolic and endocrine status in heavy veal calves. Calves were assigned to one of six degrees of separating protein and lactose over the two meals

  2. The effects of fuel characteristics and engine operating conditions on the elemental composition of emissions from heavy duty diesel buses

    Energy Technology Data Exchange (ETDEWEB)

    M.C.H. Lim; G.A. Ayoko; L. Morawska; Z.D. Ristovski; E.R. Jayaratne [Queensland University of Technology, Brisbane, Qld. (Australia). International Laboratory for Air Quality and Health, School of Physical and Chemical Sciences

    2007-08-15

    The effects of fuel characteristics and engine operating conditions on elemental composition of emissions from twelve heavy duty diesel buses have been investigated. Two types of diesel fuels - low sulfur diesel (LSD) and ultra low sulfur diesel (ULSD) fuels with 500 ppm and 50 ppm sulfur contents respectively and 3 driving modes corresponding to 25%, 50% and 100% power were used. Elements present in the tailpipe emissions were quantified by inductively coupled plasma mass spectrometry (ICPMS) and those found in measurable quantities included Mg, Ca, Cr, Fe, Cu, Zn, Ti, Ni, Pb, Be, P, Se, Ti and Ge. Multivariate analyses using multi-criteria decision making methods (MCDM), principal component analysis (PCA) and partial least squares (PLS) facilitated the extraction of information about the structure of the data. MCDM showed that the emissions of the elements were strongly influenced by the engine driving conditions while the PCA loadings plots showed that the emission factors of the elements were correlated with those of other pollutants such as particle number, total suspended particles, CO, CO{sub 2} and NOx. Partial least square analysis revealed that the emission factors of the elements were strongly dependent on the fuel parameters such as the fuel sulfur content, fuel density, distillation point and cetane index. Strong correlations were also observed between these pollutants and the engine power or exhaust temperature. The study provides insights into the possible role of fuel sulfur content in the emission of inorganic elements from heavy duty diesel vehicles. 39 refs., 1 fig., 4 tabs.

  3. Heavy rare earth elements affect early life stages in Paracentrotus lividus and Arbacia lixula sea urchins.

    Science.gov (United States)

    Oral, Rahime; Pagano, Giovanni; Siciliano, Antonietta; Gravina, Maria; Palumbo, Anna; Castellano, Immacolata; Migliaccio, Oriana; Thomas, Philippe J; Guida, Marco; Tommasi, Franca; Trifuoggi, Marco

    2017-04-01

    Heavy rare earth elements (HREEs) have been scarcely studied for their toxicity, in spite of their applications in several technologies. Thus HREEs require timely investigations for their adverse health effects. Paracentrotus lividus and Arbacia lixula embryos and sperm were exposed to trichloride salts of five HREEs (Dy, Ho, Er, Yb and Lu) and to Ce(III) as a light REE (LREE) reference to evaluate: 1) developmental defects (% DD) in HREE-exposed larvae or in the offspring of HREE-exposed sperm; 2) mitotic anomalies; 3) fertilization success; and 4) reactive oxygen species (ROS) formation, and nitric oxide (NO) and malondialdehyde (MDA) levels. Nominal HREE concentrations were confirmed by inductively coupled plasma mass spectrometry (ICP-MS). HREEs induced concentration-related DD increases in P. lividus and A. lixula larvae, ranging from no significant DD increase at 10-7M HREEs up to ≅100% DD at 10-5M HREE. Larvae exposed to 10-5M Ce(III) resulted in less severe DD rates compared to HREEs. Decreased mitotic activity and increased aberration rates were found in HREE-exposed P. lividus embryos. Significant increases in ROS formation and NO levels were found both in HREE-exposed and in Ce(III) embryos, whereas only Ce(III), but not HREEs resulted in significant increase in MDA levels. Sperm exposure to HREEs (10-5-10-4M) resulted in a concentration-related decrease in fertilization success along with increase in offspring damage. These effects were significantly enhanced for Dy(III), Ho(III), Er(III) and Yb(III), compared to Lu(III) and to Ce(III). HREE-associated toxicity affected embryogenesis, fertilization, cytogenetic and redox endpoints showing different toxicities of tested HREEs. Copyright © 2017 Elsevier Inc. All rights reserved.

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

    Indian Academy of Sciences (India)

    gamma, heavy ion and neutron array of detectors (MEGHNAD) to detect and study the properties of a wide variety of ... The gamma detector array consists of four numbers of Clover detectors, a few high efficiency HPGe ... chamber (IC) for measurement of energy and charge of the heavy ions stopping within the active gas ...

  5. [Determination of six heavy metal elements in Zanthoxylum nitidum in twelve habitats of guangxi by ICP-AES].

    Science.gov (United States)

    Wang, Dong-Mei; Feng, Jie; Qin, Fu-Jing; Mo, Yi-Sheng

    2012-03-01

    To determine the contents of six heavy metal elements in traditional Chinese medicine of Zanthoxylum nitidum in twelve habitats by ICP-AES. Nitric acid- perchloric acid mixed acid digested system was used to completely decomposed the organic compounds effectually. The As, Cr, Hg, Ni, Cd and Pb were determined by the absorption spectroscopy under set up working conditions. An efficient, simple and accurate method was established. The recoveries were 90.82%-101.21% and RSDs were within 3.0%. The contents of six heavy metal elements are different in Zanthoxylum nitidum from different habitats. As, Cr and Hg were not detected. The content of Pb which from eleven habitats is consistent with the standards of medicine and export except from Nanning habitats, meanwhile the content of Cd all exceeds those standards.

  6. HAT-P-26b: A Neptune-mass exoplanet with a well-constrained heavy element abundance.

    Science.gov (United States)

    Wakeford, Hannah R; Sing, David K; Kataria, Tiffany; Deming, Drake; Nikolov, Nikolay; Lopez, Eric D; Tremblin, Pascal; Amundsen, David S; Lewis, Nikole K; Mandell, Avi M; Fortney, Jonathan J; Knutson, Heather; Benneke, Björn; Evans, Thomas M

    2017-05-12

    A correlation between giant-planet mass and atmospheric heavy elemental abundance was first noted in the past century from observations of planets in our own Solar System and has served as a cornerstone of planet-formation theory. Using data from the Hubble and Spitzer Space Telescopes from 0.5 to 5 micrometers, we conducted a detailed atmospheric study of the transiting Neptune-mass exoplanet HAT-P-26b. We detected prominent H2O absorption bands with a maximum base-to-peak amplitude of 525 parts per million in the transmission spectrum. Using the water abundance as a proxy for metallicity, we measured HAT-P-26b's atmospheric heavy element content ([Formula: see text] times solar). This likely indicates that HAT-P-26b's atmosphere is primordial and obtained its gaseous envelope late in its disk lifetime, with little contamination from metal-rich planetesimals. Copyright © 2017, American Association for the Advancement of Science.

  7. HAT-P-26b: A Neptune-mass exoplanet with a well-constrained heavy element abundance

    Science.gov (United States)

    Wakeford, Hannah R.; Sing, David K.; Kataria, Tiffany; Deming, Drake; Nikolov, Nikolay; Lopez, Eric D.; Tremblin, Pascal; Amundsen, David S.; Lewis, Nikole K.; Mandell, Avi M.; Fortney, Jonathan J.; Knutson, Heather; Benneke, Björn; Evans, Thomas M.

    2017-05-01

    A correlation between giant-planet mass and atmospheric heavy elemental abundance was first noted in the past century from observations of planets in our own Solar System and has served as a cornerstone of planet-formation theory. Using data from the Hubble and Spitzer Space Telescopes from 0.5 to 5 micrometers, we conducted a detailed atmospheric study of the transiting Neptune-mass exoplanet HAT-P-26b. We detected prominent H2O absorption bands with a maximum base-to-peak amplitude of 525 parts per million in the transmission spectrum. Using the water abundance as a proxy for metallicity, we measured HAT-P-26b’s atmospheric heavy element content (4.8-4.0+21.5 times solar). This likely indicates that HAT-P-26b’s atmosphere is primordial and obtained its gaseous envelope late in its disk lifetime, with little contamination from metal-rich planetesimals.

  8. Effect of heavy metals on silencing of engineered long interspersed element-1 retrotransposon in nondividing neuroblastoma cell line.

    Science.gov (United States)

    Habibi, Laleh; Shokrgozar, Mohammad Ali; Motamedi, Mahdieh; Akrami, Seyed Mohammad

    2013-01-01

    L1 retrotransposons are the most active mobile DNA elements in human genome. Unregulated L1 retrotransposition may have deleterious effect by disrupting vital genes and inducing genomic instabilities. Therefore, human cells control L1 elements by silencing their activities through epigenetic mechanisms. It has been shown that cell division and heavy metals stimulate the frequency of L1 activities. Removal of silencing by L1 motivators may restart L1 element functions. Here, we have proposed that weather neurotoxic environmental heavy metals (as L1 stimulating factors) have a role in removing L1 silencing and restating its activities in nondividing neuronal cells. L1-RP green fluorescent protein (GFP)-tagged knock-in human neuroblastoma clones were prepared. Single-cell clone was treated with mitomycin-c combined with nontoxic and toxic concentrations of iron (Fe), copper (Cu), and mercury (Hg). Silencing status of engineered L1 elements in dividing and nondividing cells was determined through measuring the amount of GFP expressing cells with flow cytometry. The cytotoxic effect of mitomycin-c combined with metals was measured by MTT assay. Hg in nondividing cells and Fe, Cu, and Hg in dividing neuroblastoma cells could significantly remove L1 silencing. Also, mitomycin-c treatment did not have any effect on metal toxicity status in neuroblastoma cells. Totally, our findings have shown that cell division has a role in removing L1 silencing as well as L1 retrotransposition induced by environmental heavy metals. It has been also indicated that Hg at all concentrations could remove silencing of engineered L1 element regardless of cell cycle state.

  9. Dually Prewetted Underwater Superoleophobic and under Oil Superhydrophobic Fabric for Successive Separation of Light Oil/Water/Heavy Oil Three-Phase Mixtures.

    Science.gov (United States)

    Cao, Guoliang; Zhang, Wenbo; Jia, Zhen; Liu, Feng; Yang, Haiyue; Yu, Qianqian; Wang, Yazhou; Di, Xin; Wang, Chengyu; Ho, Shih-Hsin

    2017-10-18

    Remediation of oil spills requires new technologies to separate light oil/water/heavy oil mixtures. Low-cost, biological, and environmentally friendly materials are needed to treat water pollution caused by oils. In this study, a corn straw powder (CSP)-coated fabric (CSPF) was fabricated by spraying waste CSP and polyurethane onto amphiphilic cotton fabric, and thus, the wettability of CSPF is enhanced by taking advantage of the hierarchical structure and increased surface roughness. Therefore, the CSPF could be dually prewetted (DCSPF) with both water and oil, and it showed underwater superoleophobic and under oil superhydrophobic properties without any further chemical modification. When applied to light oil/water/heavy oil separation, the DCSPF could be used to successively separate light oil/water/heavy oil three-phase mixtures under gravity with a high separation efficiency and flux. In addition, the DCSPF showed excellent structural and chemical stability according to repeated cycling and corrosive solution/oil separation experiments. The results of this study are of value in providing a simple, low-cost, and environment-friendly approach for application in the field of successive separation of light oil/water/heavy oil three-phase mixtures.

  10. [Comparison of heavy metal elements between natural and plantation forests in a subtropical Montane forest].

    Science.gov (United States)

    Nie, Ming; Wan, Jia-Rong; Chen, Xiao-Feng; Wang, Li; Li, Bo; Chen, Jia-Kuan

    2011-11-01

    Heavy metals as one of major pollutants is harmful to the health of forest ecosystems. In the present paper, the concentrations of thirteen heavy metals (Fe, Al, Ti, Cr, Cu, Mn, V, Zn, Ni, Co, Pb, Se and Cd) were compared between natural and plantation forests in the Mt. Lushan by ICP-AES and atomic absorption spectroscopy. The results suggest that the soil of natural forest had higher concentrations of Fe, Al, Ti, Cu, Mn, V, Zn, Ni, Co, Pb, Se, and Cd than the plantation forest except for Cr. The soil of natural forest had a higher level of heavy metals than that of the plantation forest as a whole. This might be due to that the natural forest has longer age than the plantation forest, and fixed soil heavy metals take a longer period of time than the plantation forest.

  11. FINITE ELEMENT ANALYSIS OF CONCRETE FILLER INFLUENCE ON DYNAMIC RIGIDITY OF HEAVY MACHINE TOOL PORTAL

    Directory of Open Access Journals (Sweden)

    Yu. V. Vasilevich

    2016-01-01

    Full Text Available Virtual testing of portal machine tool has been carried out with the help of finite elements method (FEM. Static, modal and harmonic analyses have been made for a heavy planer. The paper reveals influence of concrete filler on machine tool dynamic flexibility. A peculiar feature of the simulation is concrete filling of a high-level transverse beam. Such approach oes look a typical one for machine-tool industry. Concrete has been considered as generalized material in two variants. It has been established that concrete application provides approximately 3-fold increase in machine tool rigidity per each coordinate. In this regard it is necessary to arrange closure of rigidity contour by filling all the cavities inside of the portal. Modal FEA makes it possible to determine that concrete increases comparatively weakly (1.3–1.4-fold frequencies of resonance modes. Frequency of the lowest mode rises only from 30.25 to 42.86 Hz. The following most active whole-machine eigenmodes have been revealed in the paper: “Portal pecking”, “Parallelogram” and “Traverse pecking”. In order to restrain the last mode it is necessary to carry out concrete filling of the traverse, in particular. Frequency-response characteristics and curves of dynamic rigidity for a spindle have been plotted for 0–150 Hz interval while using harmonic FEM. It has been determined that concrete increases dynamic machine tool rigidity by 2.5–3.5-fold. The effect is obtained even in the case when weakly damping concrete (2 % is used. This is due to distribution of vibrational energy flow along concrete and along cast iron as well. Thus energy density and vibration amplitudes must decrease. The paper shows acceptability for internal reinforcement of high-level machine tool parts (for example, portal traverses and fillers are applied for this purpose. Traverse weighting is compensated by additional torsional, shear and bending rigidity. The machine tool obtains the

  12. MODAL ANALYSIS OF CARRIER SYSTEM FOR HEAVY HORIZONTAL MULTIFUNCTION MACHINING CENTER BY FINITE ELEMENT METHOD

    Directory of Open Access Journals (Sweden)

    Yu. V. Vasilevich

    2014-01-01

    Full Text Available The aim of the paper is to reveal and analyze resonance modes of a large-scale milling-drilling-boring machine. The machine has a movable column with vertical slot occupied by a symmetrical carriage with horizontal ram. Static rigidity of the machine is relatively low due to its large dimensions. So it is necessary to assess possible vibration activity. Virtual and operational trials of the machine have been carried out simultaneously. Modeling has been executed with the help of a finite element method (FEM. The FEM-model takes into account not only rigidity of machine structures but also flexibility of bearings, feed drive systems and guides. Modal FEM-analysis has revealed eight resonance modes that embrace the whole machine tool. They form a frequency interval from 12 to 75 Hz which is undesirable for machining. Three closely located resonances (31-37 Hz are considered as the most dangerous ones. They represent various combinations of three simple motions: vertical oscillations of a carriage, horizontal vibrations of a ram and column torsion. Reliability of FEM- estimations has been proved by in-situ vibration measurements.An effect for stabilization of resonance modes has been detected while making variations in design parameters of the machine tool. For example, a virtual replacement of cast iron for steel in machine structures practically does not have any effect on resonance frequencies. Rigidity increase in some parts (e.g. a ram has also a small effect on a resonance pattern. On the other hand, resonance stability makes it possible to avoid them while selecting a spindle rotation frequency.It is recommended to set double feed drives for all axes. A pair of vertical screws prevents a “pecking” resonance of the carriage at frequency of 54 Hz. It is necessary to foresee an operation of a main drive of such heavy machine tool in the above resonance interval with the spindle frequency of more than 75 Hz. For this purpose it is necessary

  13. Process and method for the processing of minerals such as coal or ore, by means of a heavy-medium separation unit. Verfahren und Vorrichtung zur Aufbereitung von Mineralien, wie zum Beispiel Kohle oder Erz, mittels einer Schwertruebe-Trennvorrichtung

    Energy Technology Data Exchange (ETDEWEB)

    Farahmand, A.; Rathnow, E.

    1986-03-06

    The generally known processing methods for coarse-grained minerals as for example coal or ore, by means of a heavy-medium separation device, have the disadvantage that it is necessary for the heavy-medium production to use foreign matters, such as ferrochromium, as heavy medium; the provision and reprocessing of the foreign matters cause a relatively high expenditure of work and costs. According to the invention, the disadvantages are eliminated by the fact that the heavy-medium production is done by means of heavy material that is obtained during the processing of the minerals in the heavy-medium separation device designed as jig washer. (orig.).

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

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... In the coming decade, the expanding field of experimental nuclear physics in our country is going to see a quantum leap in research and developmental activities with new accelerator facilities like the variable energy cyclotron with ECR heavy ion source, the upcoming K-500 superconducting cyclotron, ...

  15. Mobilization of heavy metals from contaminated paddy soil by EDDS, EDTA, and elemental sulfur

    NARCIS (Netherlands)

    Wang, G.; Koopmans, G.F.; Song, J.; Temminghoff, E.J.M.; Luo, Y.; Zhao, Q.; Japenga, J.

    2007-01-01

    For enhanced phytoextraction, mobilization of heavy metals (HMs) from the soil solid phase to soil pore water is an important process. A pot incubation experiment mimicking field conditions was conducted to investigate the performance of three soil additives in mobilizing HMs from contaminated paddy

  16. Distribution of heavy elements in urban and rural surface soils: the Novi Sad city and the surrounding settlements, Serbia.

    Science.gov (United States)

    Škrbić, Biljana; Đurišić-Mladenović, Nataša

    2013-01-01

    Concentrations of ten heavy elements (Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn), as well as the pH values, organic matter contents, and electrical conductivities were measured in the surface soil samples collected from 21 sites of urban areas in the city of Novi Sad, the second largest city in Serbia, its suburban settlement and the nearby villages. Range of the heavy element concentrations was from 0.16 mg/kg (for Hg) to 18,994 mg/kg (for Fe). Significantly higher Hg and Mn concentrations were observed in subgroups with rural and market garden samples in comparison to the subgroups with urban and grassland samples, respectively, while the contents of Pb found in the grasslands subgroup were significantly higher than in the subgroup with market garden soils. Only one sample of urban soil exceeded the maximum permissible value for Zn set by the relevant Serbian legislation. According to the Dutch soil quality standard, the Cd and Co concentrations in majority of the examined soils were higher than the target values for unpolluted soil. The content of Hg was above the target value in 52% of the samples, most of them belonging to the subgroup of market garden soils. The results for the Novi Sad city area were compared to the relevant data available for other cities in the Western Balkan Countries. Principal component analysis of data revealed seven outlying samples, while the rest of the analyzed samples were grouped together indicating similar heavy element patterns most probably due to mixed emission sources.

  17. The Origins of Light and Heavy R-process Elements Identified by Chemical Tagging of Metal-poor Stars

    Science.gov (United States)

    Tsujimoto, Takuji; Shigeyama, Toshikazu

    2014-11-01

    Growing interests in neutron star (NS) mergers as the origin of r-process elements have sprouted since the discovery of evidence for the ejection of these elements from a short-duration γ-ray burst. The hypothesis of a NS merger origin is reinforced by a theoretical update of nucleosynthesis in NS mergers successful in yielding r-process nuclides with A > 130. On the other hand, whether the origin of light r-process elements are associated with nucleosynthesis in NS merger events remains unclear. We find a signature of nucleosynthesis in NS mergers from peculiar chemical abundances of stars belonging to the Galactic globular cluster M15. This finding combined with the recent nucleosynthesis results implies a potential diversity of nucleosynthesis in NS mergers. Based on these considerations, we are successful in the interpretation of an observed correlation between [light r-process/Eu] and [Eu/Fe] among Galactic halo stars and accordingly narrow down the role of supernova nucleosynthesis in the r-process production site. We conclude that the tight correlation by a large fraction of halo stars is attributable to the fact that core-collapse supernovae produce light r-process elements while heavy r-process elements such as Eu and Ba are produced by NS mergers. On the other hand, stars in the outlier, composed of r-enhanced stars ([Eu/Fe] gsim +1) such as CS22892-052, were exclusively enriched by matter ejected by a subclass of NS mergers that is inclined to be massive and consist of both light and heavy r-process nuclides.

  18. 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

  19. Behavior and Distribution of Heavy Metals Including Rare Earth Elements, Thorium, and Uranium in Sludge from Industry Water Treatment Plant and Recovery Method of Metals by Biosurfactants Application

    Science.gov (United States)

    Gao, Lidi; Kano, Naoki; Sato, Yuichi; Li, Chong; Zhang, Shuang; Imaizumi, Hiroshi

    2012-01-01

    In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs), thorium (Th), and uranium (U) in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni) from the polluted sludge was studied with biosurfactant (saponin and sophorolipid) elution by batch and column experiments to evaluate the efficiency of biosurfactant for the removal of heavy metals. Consequently, the following matters have been largely clarified. (1) Heavy metallic elements in sludge have generally larger concentrations and exist as more unstable fraction than those in natural soil. (2) Nonionic saponin including carboxyl group is more efficient than sophorolipid for the removal of heavy metals in polluted sludge. Saponin has selectivity for the mobilization of heavy metals and mainly reacts with heavy metals in F3 (the fraction bound to carbonates) and F5 (the fraction bound to Fe-Mn oxides). (3) The recovery efficiency of heavy metals (Pb, Ni, and Cr) reached about 90–100% using a precipitation method with alkaline solution. PMID:22693485

  20. Sources and contents of heavy metals and other trace elements in animal manure

    Science.gov (United States)

    Trace elements take part in various physiological functions including enzyme formation, vitamin formation, metabolism, and electron transport in animals. Thus, trace elements are added to livestock and poultry diets to prevent diseases, improve weight gains and feed conversion, and increase egg prod...

  1. Exploring Elements of Fun to Motivate Heavy Drinking Youth to (retrain Cognition

    Directory of Open Access Journals (Sweden)

    Wouter Boendermaker

    2015-09-01

    Adding (social game elements can increase motivation to train, and while the mobile training did not appear to be more motivating, it also did not underperform compared to the regular training in this sample. This warrants more research into motivational elements for CBM training in younger audiences.

  2. Finite element modeling simulation-assisted design of integrated microfluidic chips for heavy metal ion stripping analysis

    Science.gov (United States)

    Hong, Ying; Zou, Jianhua; Ge, Gang; Xiao, Wanyue; Gao, Ling; Shao, Jinjun; Dong, Xiaochen

    2017-10-01

    In this article, a transparent integrated microfluidic device composed of a 3D-printed thin-layer flow cell (3D-PTLFC) and an S-shaped screen-printed electrode (SPE) has been designed and fabricated for heavy metal ion stripping analysis. A finite element modeling (FEM) simulation is employed to optimize the shape of the electrode, the direction of the inlet pipeline, the thin-layer channel height and the sample flow rate to enhance the electron-enrichment efficiency for stripping analysis. The results demonstrate that the S-shaped SPE configuration matches the channel in 3D-PTLFC perfectly for the anodic stripping behavior of the heavy metal ions. Under optimized conditions, a wide linear range of 1-80 µg l-1 is achieved for Pb2+ detection with a limit of 0.3 µg l-1 for the microfluidic device. Thus, the obtained integrated microfluidic device proves to be a promising approach for heavy metal ions stripping analysis with low cost and high performance.

  3. The ultrasound assisted extraction of matrix elements and heavy metal fractions associated with Fe, Al and Mn oxyhydroxides from soil

    Directory of Open Access Journals (Sweden)

    Stanišić Svetlana M.

    2012-01-01

    Full Text Available The single agent extractions of major and trace metals from soil sample were conducted by means of rotary mixer and ultrasonic bath with sonication time of 10, 20, 30, 40 and 50 min. The sequential extraction according to the BCR scheme was undertaken. The obtained soil extracts were analyzed by ICP-OES and according to the results the rotary mixer assisted extraction was more efficient in the case of alkaline-earth elements. However, by the use of ultrasound several times higher amounts of matrix elements (Fe, Al and Mn and heavy metals predominantly associated with Fe, Al and Mn oxyhydroxides were extracted. The increase of the sonication time failed to improve extraction yields. The changes of the conductivity, pH, oxidoreduction potential, particle size diameter and zeta potential of colloid particles, with the sonication time increase were measured. The extraction mechanism and expressed selectivity of ultrasound is discussed and explanation is suggested.

  4. The Effect of Cocoa Beans Heavy and Trace Elements on Safety and Stability of Confectionery Products

    Directory of Open Access Journals (Sweden)

    Vītola Vineta

    2016-06-01

    Full Text Available The aim of the study was to evaluate cocoa beans quality produced in Cameroon, Ecuador, Nigeria and Ghana from safety position determining heavy and trace metals concentration and evaluating the oxidative stability of confectionery products prototypes (trials with analysing cocoa beans. For evaluation of oxidative stability of confectionery products, the main ingredients - butter and cocoa beans kernels were tested making trials as milk chocolate prototype.

  5. Separation characteristics of rare earth elements in the TOPO/DTPA - Salting-out reagent solution system

    Energy Technology Data Exchange (ETDEWEB)

    Miyahara, S.; Koma, Yoshikazu; Koyama, Tomozo; Tanaka, Yasumasa [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan). Tokai Works; Kano, J.

    1998-11-01

    A test of mutual separation of rare earth elements was carried out using an organic phosphorus extraction solvent TOPO (tri-octyl phosphorus oxide). It was found that the distribution ratio monotonously increased with the atomic number and the separation factor of La/Ln was 10{sup 3}. Under the condition that a sufficient quantity of DTPA compared with the amount of rare earth metals and pH > 1.5 in which DTPA easily formed complexes with lanthanides, the following conclusions were obtained; (i) the separation factor was not affected by pH, the kind of salting-out reagent, or the concentration, (ii) the extraction reaction with TOPO and complex formation with DTPA mainly contributed to the separation of lanthanides, and (iii) the separation factor computed by means of the distribution ratio of TOPO extraction and complex formation constant for DTPA more or less agreed with the empirical value. Separation of rare earth elements using TOPO revealed similar characteristics to those of systems with CMPO and TBP. (H. Baba)

  6. Effects of alloying elements on the formation of < c >-component loops in Zr alloy Excel under heavy ion irradiation.

    Energy Technology Data Exchange (ETDEWEB)

    Idrees, Yasir; Francis, Elisabeth M.; Yao, Zhongwen; Korinek, Andreas; Kirk, Marquis A.; Sattari, Mohammad; Preuss, Michael; Daymond, M. R.

    2015-05-14

    We report here the microstructural changes occurring in the zirconium alloy Excel (Zr-3.5 wt% Sn-0.8Nb-0.8Mo-0.2Fe) during heavy ion irradiation. In situ irradiation experiments were conducted at reactor operating temperatures on two Zr Excel alloy microstructures with different states of alloying elements, with the states achieved by different solution heat treatments. In the first case, the alloying elements were mostly concentrated in the beta (beta) phase, whereas, in the second case, large Zr-3(Mo,Nb,Fe)(4) secondary phase precipitates (SPPs) were grown in the alpha (alpha) phase by long term aging. The heavy ion induced damage and resultant compositional changes were examined using transmission electron microscopy (TEM) in combination with scanning transmission electron microscope (STEM)-energy dispersive x-ray spectroscopy (EDS) mapping. Significant differences were seen in microstructural evolution between the two different microstructures that were irradiated under similar conditions. Nucleation and growth of < c >-component loops and their dependence on the alloying elements are a major focus of the current investigation. It was observed that the < c >-component loops nucleate readily at 100, 300, and 400 degrees C after a threshold incubation dose (TID), which varies with irradiation temperature and the state of alloying elements. It was found that the TID for the formation of < c >-component loops increases with decrease in irradiation temperature. Alloying elements that are present in the form of SPPs increase the TID compared to when they are in the beta phase solid solution. Dose and temperature dependence of loop size and density are presented. Radiation induced redistribution and clustering of alloying elements (Sn, Mo, and Fe) have been observed and related to the formation of < c >-component loops. It has been shown that at the higher temperature tests, irradiation induced dissolution of precipitates occurs whereas irradiation induced

  7. Re-evaluation of interferences of doubly charged ions of heavy rare earth elements on Sr isotopic analysis using multi-collector inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Yang, Yue-Heng; Wu, Fu-Yuan; Xie, Lie-Wen; Chu, Zhu-Yin; Yang, Jin-Hui

    2014-07-01

    We re-evaluate the interference of doubly charged heavy rare earth elements during Sr isotopic analysis using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). A series of mixed solutions of standard reference material SRM 987, rare earth elements, and Sr separated from rock reference materials are measured to assess the influence of isobaric interferences on the MC-ICP-MS analysis of Sr isotopes. After sample dissolution, conventional cation-exchange chromatography is employed for Sr purification of rock reference materials prior to MC-ICP-MS measurement. It has been demonstrated that if the natural abundances of Er and Yb are used to correct for doubly charged ion interferences on Sr, an overcorrection results. In contrast, the use of measured doubly charged ion ratios results in an accurate and precise correction of isobaric interference. This finding is confirmed by analytical results for several certified reference materials from mafic (basaltic) to felsic (granitic) silicate rocks. It is noteworthy that, because Er is more prone to doubly charged ion formation, it dominates over Yb doubly charged ions as an interference source.

  8. Analysis of Nuclear Reactions Used for the Synthesis of Heavy and Superheavy Elements in the Framework of the Dinuclear System Concept

    CERN Document Server

    Volkov, V V

    2003-01-01

    Reactions used for the synthesis of heavy and superheavy elements are analyzed within the framework of the dinuclear system concept. The important role of quasi- fission and the inner fusion potential barrier is emphasized. The results of calculation of the production cross sections for heavy and superheavy elements synthesized in cold and hot fusion reactions are given in comparison with experimental data. The minimum value of compound nucleus excitation energy is calculated for elements from 104 to 114, produced in cold fusion reactions. This article is a short survey of some results obtained by a group of physicists, using the dinuclear system concept.

  9. Identifying and separating magnetic and electric microwave responses of chiral elements

    Science.gov (United States)

    Kazantsev, Yu. N.; Kraftmakher, G. A.; Mal'tsev, V. P.

    2016-03-01

    We propose a technique for identifying the type of resonance excitation by ac magnetic or electric fields in conducting chiral elements by reflection of electromagnetic waves in the standing- and travelingwave modes. The technique was tested experimentally in the microwave range and confirmed numerically. We demonstrate the possibility of broadband matching of composite radar absorbing materials with the use of a lattice of resonance elements excited by magnetic field of the wave rather instead of the traditional quarter- wavelength effects.

  10. Glann Seaborg's Contributions to Heavy Element Science and the Periodic Table

    Energy Technology Data Exchange (ETDEWEB)

    Hobart, David E. [Los Alamos National Laboratory

    2012-08-17

    In celebrating the centennial anniversary of the birth of Glenn T. Seaborg it is fitting that we recount and pay tribute to his legacy. Many know of the scientific accomplishments of this man who became a legend and anyone who has attended his lectures can attest to how informative, educational, and entertaining he was. He had a beguiling and whimsical sense of humor and used this to drive home his points and share his passion and quest for discovery. The periodic table is a fundamental cornerstone of science and remains a central unifying principal. Seaborg was the architect of the actinide series of elements and their proper placement in the periodic table and co-discoverer of ten transuranium elements - one of which bears his name, element 106, seaborgium. The work and achievements of this Nobel laureate have touched the lives of many and his legacy will continue for generations to come.

  11. 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/.

  12. Purification And Separation Of Rare Earth Elements From CCFL With Extraction Chromatography

    Directory of Open Access Journals (Sweden)

    Kim J.-G.

    2015-06-01

    Full Text Available In this study, Amberite XAD-7HP was used as the solvent-impregnated resin to separate each REE from the standard solution, which was mixed with the REEs (e.g., La Eu, Tb, Y and Ba. About 100 ppm of each of the REEs was separated from DI water using extraction chromatography. REEs were separated by extraction chromatography using Amberite XAD-7HP resin, the changes in the pH values of the HCl and HClO4 were between 0.2 N and 5 N, and the extraction rate of the solution was between 0.5 and 3 ml/min. The La solution with the separated REEs was leached. The solid-state REEs were annealed between 1083K. The extraction result was analyzed with ICP-AES and an X-ray diffractometer. Each REE was successfully separated with HCl and HClO4 with pH values between 0.1 N and 3 N and with extraction rate between 1.0 m/min and 3.0 m/min.

  13. Study of heavy metals and other elements in macrophyte algae using energy-dispersive X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, M.L.; Amorim, P.; Marques, M.I.M.; Ramos, M.T. [Univ. de Lisboa (Portugal); Ferreira, J.G. [Faculdade de Ciencias e Tecnologia, Monte de Caparica (Portugal). Dept. Ciencias e Engenharia do Ambiente

    1997-04-01

    Fucus vesiculosus L. seaweeds from three estuarine stations were analyzed by X-ray fluorescence, providing results for the concentration of total K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Sr, and Pb. Four different structures of the algae (base, stipe, reproductive organs, and growing tips) were analyzed to study the differential accumulation of heavy metals by different parts of Fucus. Some elements (e.g., Cu and Fe) are preferentially accumulated in the base of the algae, whereas others (e.g., As) exhibit higher concentrations in the reproductive organs and growing tips. The pattern of accumulation in different structures is similar for Cu, Zn, and Pb, but for other metals there is considerable variability in accumulation between parts of the plant. This is important in determining which structures of the plant should be used for biomonitoring. For samples collected at stations subject to differing metal loads, the relative elemental composition is approximately constant, notwithstanding significant variation in absolute values. The proportion of metals in Fucus is similar to that found in other estuaries, where metal concentrations are significantly lower. Energy-dispersive X-ray fluorescence has been shown to be a suitable technique for multielement analysis in this type of sample. No chemical pretreatment is required, minimizing sample contamination. The small amount of sample required, and the wide range of elements that can be detected simultaneously make energy-dispersive X-ray fluorescence a valuable tool for pollution studies.

  14. Quantitative analysis of some oligo-elements and heavy metals in some species of Thymus from Morocco.

    Science.gov (United States)

    Bennouna, M A; Belaqziz, R; Arjouni, M Y; Romane, A

    2013-01-01

    In order to valorise natural substances, concentrations of 20 mineral elements were evaluated in five species of Moroccan thyme. These species which belong to the Lamiaceae family are Thymus leptobotrys, Thymus broussonetii, Thymus maroccanus, Thymus pallidus and Thymus satureioïdes growing in different regions of central and southern Morocco. Samples of plants were subjected to digestion and heavy metals were determined by inductively coupled plasma mass spectrometry. The highest concentrations of calcium, iron, zinc, cobalt and chromium were registered in T. broussonetii, T. pallidus, T. leptobotrys, T. maroccanus and T. satureioïdes with respective values of 1991, 423, 73, 6 and 11 mg/kg. Furthermore, silicium and boron were analysed only for the species T. broussonetii and their respective concentrations were found to be 112 and 43 mg/kg. The ultra trace elements Si, B, Ni, Ni, As, Li, V and toxic elements Cd and Pb were also evaluated. The results were treated by the method of principal components analysis.

  15. Perspectives of Super-Heavy Nuclei research with the upcoming separator-spectrometer setup S3 at GANIL/SPIRAL2 - The VAMOS Gas-Filled separator and AGATA

    Science.gov (United States)

    Theisen, Christophe

    2017-11-01

    Several facilities or apparatus for the synthesis and spectroscopy of the Super-Heavy Nuclei (SHN) are presently under construction in the world, which reflect the large interest for this region of extreme mass and charge, but also for the need of even more advanced research infrastructures. Among this new generation, the GANIL/SPIRAL2 facility in Caen, France, will soon deliver very high intense ion beams of several tens of particle μA. The Super Separator Spectrometer S3 has been designed to exploit these new beams for the study of SHN after separation. It will provide the needed beam rejection, mass selection and full arsenal of state-of-the art detection setups. Still at GANIL, the AGATA new generation gamma-ray tracking array is being operated. The VAMOS high acceptance spectrometer is being upgraded as a gas-filled separator. Its coupling with AGATA will lower the spectroscopic limits for the prompt gamma-ray studies of heavy and super-heavy nuclei. In this proceeding, these new devices will be presented along with a selected physics case.

  16. Trace elements and heavy metals in the Grand Bay National Estuarine Reserve in the northern Gulf of Mexico

    Science.gov (United States)

    McComb, Jacqueline Q.; Han, Fengxiang X.; Rogers, Christian; Thomas, Catherine; Arslan, Zikri; Ardeshir, Adeli; Tchounwou, Paul B.

    2015-01-01

    The objectives of this study are to investigate distribution of trace elements and heavy metals in the salt marsh and wetland soil and biogeochemical processes in the Grand Bay National Estuarine Research Reserve of the northern Gulf of Mexico. The results show that Hg, Cd and to some extent, As and Pb have been significantly accumulated in soils. The strongest correlations were found between concentrations of Ni and total organic matter contents. The correlations decreased in the order: Ni > Cr > Sr > Co > Zn, Cd > Cu > Cs. Strong correlations were also observed between total P and concentrations of Ni, Co, Cr, Sr, Zn, Cu, and Cd. This may be related to the P spilling accident in 2005 in the Bangs Lake site. Lead isotopic ratios in soils matched well those of North American coals, indicating the contribution of Pb through atmospheric fallout from coal power plants. PMID:26238403

  17. Multiplet splitting for the XPS of heavy elements: Dependence on oxidation state

    Science.gov (United States)

    Bagus, Paul S.; Nelin, Connie J.; Al-Salik, Yahya; Ilton, Eugene S.; Idriss, Hicham

    2016-01-01

    Multiplet splittings in X-ray Photo-electron Spectroscopy, XPS, are a means of distinguishing different open shell occupations, or different oxidation states, in a material being studied. Indeed, especially for 3d transition metal complexes, they have provided fingerprints of the metal oxidation state. The present work provides theoretical and experimental evidence that it may also be possible to use multiplets to characterize the oxidation state of heavy metal, lanthanide and actinide, cations in complexes. However, it is important to make a proper choice of the XPS region to study in order to obtain large multiplet splittings. We identify a low binding energy, BE, peak that had been observed for Ce(III) in CeOx as a high spin coupled multiplet. Furthermore, we show that a low BE feature with reasonable intensity is characteristic of other XPS regions and of other metals. This feature arises from a high spin multiplet and serves as a fingerprint to distinguish closed shell from open shell cations. Evidence is presented that it may also be possible to distinguish different open shell occupations.

  18. Heavy metal incorporation in foraminiferal calcite: results from multi-element enrichment culture experiments with Ammonia tepida

    Directory of Open Access Journals (Sweden)

    G.-J. Reichart

    2010-08-01

    Full Text Available The incorporation of heavy metals into carbonate tests of the shallow water benthic foraminifer Ammonia tepida was investigated under controlled laboratory conditions. Temperature, salinity, and pH of the culture solutions were kept constant throughout the duration of this experiment, while trace metal concentrations were varied. Concentrations of Ni, Cu, and Mn were set 5-, 10-, and 20 times higher than levels found in natural North Sea water; for reference, a control experiment with pure filtered natural North Sea water was also analysed. The concentrations of Cu and Ni from newly grown chambers were determined by means of both μ-synchrotron XRF and Laser Ablation Inductively Coupled Plasma Mass Spectroscopy (LA-ICP-MS. The results of both independent analytical techniques agreed within the analytical uncertainty. In general, the concentration of the analysed elements in the tests increased in line with their concentration in the culture solutions. Potential toxic and/or chemical competition effects might have resulted in the decreased incorporation of Ni and Cu into the calcite of the specimens exposed to the highest elemental concentrations. Mn incorporation exhibited large variability in the experiment with the 20-fold increased element concentrations, potentially due to antagonistic effects with Cu. The partition coefficients of Cu and Ni were calculated to be 0.14 ± 0.02 and 1.0 ± 0.5, respectively, whereas the partition coefficient of Mn was estimated to be least 2.4. These partition coefficients now open the way for reconstructing past concentrations for these elements in sea water.

  19. Extraction chromatographic separation of platinum (IV) from real samples and associated elements.

    Science.gov (United States)

    Kokate, Sudarshan Jagdish; Kuchekar, Shashikant Raghunath

    2009-11-01

    The extraction behavior of platinum (IV) was studied with N-n-octylaniline as a function of different parameters, such as pH, concentrations of weak acids, mineral acids, reagents and elution time. A selective method was developed for the extraction chromatographic studies of platinum (IV) and its separation from several metal ions with N-n-octylaniline (liquid anion exchanger) as a stationary phase on silica gel. The quantitative extraction of platinum (IV) was observed with 0.067 mol/L N-n-octylaniline and 0.015 mol/L ascorbic acid at pH 1.0. Metal ion was stripped from the column with water and determined spectrophotometrically with stannous chloride method. The proposed method is free from the interference of a large number of cations and anions. Platinum (IV) was separated from pharmaceutical preparations, alloys and synthetic mixtures. Mutual separation scheme was developed for platinum (IV), palladium (II) and gold (III). The log-log plot of N-n-octylaniline concentration versus the distribution ratio indicates that the probable extracted species is [RR'NH2+] x Pt (C6H7O6)3-.

  20. Heavy metal, trace element and petroleum hydrocarbon pollution in the Arabian Gulf: Review

    Directory of Open Access Journals (Sweden)

    Afnan Mahmood Freije

    2015-04-01

    Full Text Available The Arabian Gulf environmental status was assessed based on studies conducted in Bahrain, Kuwait, Oman, Saudi Arabia, Qatar, and United Arab Emirates (UAE during 1983–2011. This review examines all sorts of pollutions in the Arabian Gulf area over the last three decades. Approximately 50 published studies were reviewed in order to determine the pollution status in the Arabian Gulf regarding heavy metals and organic substances. Three types of environmental pollutions including marine and coastal, soil, and air were addressed in this review as well as sources of pollutants and their effect on biological systems, marine organisms, and human health. Emphasis is placed on marine pollution, particularly toxic metal, and petroleum hydrocarbon contaminations. Major parts of this review discuss the consequences of the 1991 Gulf War on the environment, and the substantial changes associated with the marine habitats. The effects of oil field fires in Kuwait following the 1991 Gulf War were evaluated through studies that investigated hydrocarbons concentration and trace metals in samples of near shore sediments, bivalves, and fish collected from Kuwait, Saudi Arabia, Bahrain, UAE, and Oman. Total petroleum hydrocarbons (TPH and polycyclic aromatic hydrocarbons (PAHs were discussed in biota (fish and various bivalves and coastal sediments from six countries in the Gulf. The review has revealed different concentrations of pollutants, low, moderately, and chronically contaminated areas from oil and metals. It has also outlined effective sustainable management measures and goals as a first step in the evaluation of coastal, marine, soil, and air environment in the Arabian Gulf area.

  1. FINITE ELEMENT ANALYSIS OF CENTRELESS-LUNETTE TURNING OF HEAVY SHAFT

    Directory of Open Access Journals (Sweden)

    Yu. V. Vasilevich

    2017-01-01

    Full Text Available Dynamics of huge renovated lathe is simulated. Turning scheme concerns to heavy rotor shaft finishing. Lofty parts and milling head may create dynamic problems. Static, modal and harmonic frequency response function simulations were provided. Bearing system consists of bed, support, tool, lunettes, tailstock. Headstock didn’t take part in shaft holding. Static and dynamic rigidities founded 3–4 times less for support than for shaft. Tool rigidity lessens from 186.5 to 11.9 N/µm for speeding from slow to near resonance turning. Twelve lathe eigenmodes were evaluated. Two eigenmodes are most dangerous. It is “shaft swinging on lunettes” (M1, 26.7 Hz and “support pecking” (M3, 54.4 Hz. Bed has excessive flexibility due to through holes and lack of inner ribbing. Polymer concrete filling is moderately effective. Changing two-lunette (2L scheme to three-lunette (3L increases rigidity of shaft at 2.09 times at statics but gives limited action in dynamics. Resonant peaks on frequency response function are lowered only at 1.32 times for M1, M3. Effect of dynamic damping is revealed under condition of proximity middle lunette to lofty support. Support serves as tuned mass damper. Measures of machine tool reinforcement are simulated. Shaft swinging according to M1 may hardly be blocked by passive means. It would be better to bypass it. “Support pecking” resonance (M3 succumbs to only full set of measures. Small effect of partial reinforcement is predicted. Three frequency intervals are recommended for turn-milling at huge lathe: pre-resonant (<20 Hz, inter-resonant (35–45 Hz and post-resonant (>65 Hz. The last one is more suited. Next design step is to create triangle inner ribbing system or caissons inside of bed.

  2. Development of several chromatography extraction separations for the measurement of minority elements present in high level radioactive solutions

    Energy Technology Data Exchange (ETDEWEB)

    Maillard, Christophe; Esbelin, Eric; Dautheriebes, Jean-Luc [CEA, Bagnols sur Ceze (France). Analysis and Materials Metrology Lab.

    2016-05-01

    Five chromatography extraction separation methods using Triskem columns were developed for the measurement of minority elements present in high level activity solutions produced by various programs (processes of hydrometallurgical extraction, dissolution of hulls and spent fuels) implemented in the Atalante facility at CEA Marcoule. The first three concern the Purex process, for which it is necessary to quantify Np + Pu traces in the main raffinate, Np traces in the ''U-Pu production'' step, and Tc traces in the ''U production'' to qualify its performances. Total recovery of these traces was obtained with a good macro-element decontamination factor, thus permitting their determination by L-line X-ray fluorescence or by ICP-QMS. The fourth separation focussed on the total recovery of U and Pu traces from a hull dissolution solution. The decontamination and recovery performances were very good and enabled the determination of U and Pu by L-line X-ray fluorescence. The last method concerns the separation of Zr from an irradiated fuel dissolution solution, for its isotopic composition determination by ICP-QMS. Excellent agreement was obtained between the experimental measurements and computer code estimates.

  3. Accumulation of heavy metals and trace elements in fluvial sediments received effluents from traditional and semiconductor industries.

    Science.gov (United States)

    Hsu, Liang-Ching; Huang, Ching-Yi; Chuang, Yen-Hsun; Chen, Ho-Wen; Chan, Ya-Ting; Teah, Heng Yi; Chen, Tsan-Yao; Chang, Chiung-Fen; Liu, Yu-Ting; Tzou, Yu-Min

    2016-09-29

    Metal accumulation in sediments threatens adjacent ecosystems due to the potential of metal mobilization and the subsequent uptake into food webs. Here, contents of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) and trace elements (Ga, In, Mo, and Se) were determined for river waters and bed sediments that received sewage discharged from traditional and semiconductor industries. We used principal component analysis (PCA) to determine the metal distribution in relation to environmental factors such as pH, EC, and organic matter (OM) contents in the river basin. While water PCA categorized discharged metals into three groups that implied potential origins of contamination, sediment PCA only indicated a correlation between metal accumulation and OM contents. Such discrepancy in metal distribution between river water and bed sediment highlighted the significance of physical-chemical properties of sediment, especially OM, in metal retention. Moreover, we used Se XANES as an example to test the species transformation during metal transportation from effluent outlets to bed sediments and found a portion of Se inventory shifted from less soluble elemental Se to the high soluble and toxic selenite and selenate. The consideration of environmental factors is required to develop pollution managements and assess environmental risks for bed sediments.

  4. Levels and spatial distribution of airborne chemical elements in a heavy industrial area located in the north of Spain.

    Science.gov (United States)

    Lage, J; Almeida, S M; Reis, M A; Chaves, P C; Ribeiro, T; Garcia, S; Faria, J P; Fernández, B G; Wolterbeek, H T

    2014-01-01

    The adverse health effects of airborne particles have been subjected to intense investigation in recent years; however, more studies on the chemical characterization of particles from pollution emissions are needed to (1) identify emission sources, (2) better understand the relative toxicity of particles, and (3) pinpoint more targeted emission control strategies and regulations. The main objective of this study was to assess the levels and spatial distribution of airborne chemical elements in a heavy industrial area located in the north of Spain. Instrumental and biomonitoring techniques were integrated and analytical methods for k0 instrumental neutron activation analysis and particle-induced x-ray emission were used to determine element content in aerosol filters and lichens. Results indicated that in general local industry contributed to the emissions of As, Sb, Cu, V, and Ni, which are associated with combustion processes. In addition, the steelwork emitted significant quantities of Fe and Mn and the cement factory was associated with Ca emissions. The spatial distribution of Zn and Al also indicated an important contribution of two industries located outside the studied area.

  5. Accumulation of heavy metals and trace elements in fluvial sediments received effluents from traditional and semiconductor industries

    Science.gov (United States)

    Hsu, Liang-Ching; Huang, Ching-Yi; Chuang, Yen-Hsun; Chen, Ho-Wen; Chan, Ya-Ting; Teah, Heng Yi; Chen, Tsan-Yao; Chang, Chiung-Fen; Liu, Yu-Ting; Tzou, Yu-Min

    2016-09-01

    Metal accumulation in sediments threatens adjacent ecosystems due to the potential of metal mobilization and the subsequent uptake into food webs. Here, contents of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) and trace elements (Ga, In, Mo, and Se) were determined for river waters and bed sediments that received sewage discharged from traditional and semiconductor industries. We used principal component analysis (PCA) to determine the metal distribution in relation to environmental factors such as pH, EC, and organic matter (OM) contents in the river basin. While water PCA categorized discharged metals into three groups that implied potential origins of contamination, sediment PCA only indicated a correlation between metal accumulation and OM contents. Such discrepancy in metal distribution between river water and bed sediment highlighted the significance of physical-chemical properties of sediment, especially OM, in metal retention. Moreover, we used Se XANES as an example to test the species transformation during metal transportation from effluent outlets to bed sediments and found a portion of Se inventory shifted from less soluble elemental Se to the high soluble and toxic selenite and selenate. The consideration of environmental factors is required to develop pollution managements and assess environmental risks for bed sediments.

  6. Light element analysis in steel by high-energy heavy-ion time of flight elastic recoil detection analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hong, W.; Hayakawa, S.; Gohshi, Y. [University of Tokyo, 3-1, Hongo 7 chome, Bunkyo-Ku, Tokyo (Japan); Maeda, K.; Fukuda, S. [The Institute of Physical and Chemical Research (RIKEN), Wako, Saitama (Japan)

    1999-01-04

    Time of flight elastic recoil detection analysis (TOF-ERDA) using high-energy heavy ions has been applied to determining the composition of light elements in stainless-steel (SUS304) samples before and after welding in order to monitor the variation in the composition of light elements in sample surfaces during a welding process. An argon-welding method using a welding rod (SUS304) and an arc-welding method using a welding rod were used to prepare samples. Four samples, welded and non-welded using two welding methods, were measured. {sup 40}Ar ions accelerated to 40.3 MeV were used as a probe. Carbon, oxygen and sodium were measured. It was found that the oxygen distributions near to the surfaces of the welded samples increased compared with those of the non-welded samples. However, variations in the carbon distributions were relatively smaller than that of oxygen distributions. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  7. Heavy metals and trace elements in hair and urine of a sample of arab children with autistic spectrum disorder.

    Science.gov (United States)

    Blaurock-Busch, Eleonor; Amin, Omnia R; Rabah, Thanaa

    2011-10-01

    General information: Autism is a severe developmental disorder which involves social withdrawal, communication deficits, and stereotypic/repetitive behavior. The pathophysiological etiologies which precipitate autism symptoms remain elusive and controversial in many cases, but both genetic and environmental factors (and their interactions) have been implicated. While autism is considered multicausal, environmental factors have received significant attention. International discussion has ocused on neurotoxins such as mercury and lead, suggesting that these and other toxic metals contribute to the development of the disorder. An epidemiological study released in 2006 (Palmer et al.) linking Toxic Release Inventory (TRI) data on mercury to special education data in Texas reported a 61% increase in autism prevalence rates (or 17% adjusted) per 1000 pounds of mercury released into the environment (1). We attempted to further evaluate whether exposure to variable environmental contributes to the genesis of autistic spectrum disorder, and thus is a factor increasing the risk for developing autism symptoms in utero or in early childhood. The purpose of this study is to examine possible environmental risk factors and sources of exposure to mercury and other heavy metals in children with autism spectrum disorder versus controls. Through laboratory diagnostics we are able to distinguish between present and past exposure (i.e. hair analysis measurements reflect past exposure), urinary excretion levels of unprovoked urine represent immediate exposure. By assessing a spectrum of trace elements and heavy metals in hair and urine of both autistic and control groups, we focused on the participants≈ past and present exposure. The participants were 25 Autistic Spectrum Disorder (ASD) children (22 boys and 3 girls) between the age of 3 and 9 years. They were either diagnosed previously by other psychiatrist, psychologist, and developmental pediatrician or suspected by their parents

  8. Electronic Structure Calculations for Heavy Elements: Radon (Z=86) and Francium (Z=87)

    Science.gov (United States)

    Koufos, Alexander; Papaconstantopoulos, Dimitrios

    2010-03-01

    Electronic structure calculations allow scientists to predict the properties of solids without the use of physical material. Although the ability to manipulate matter has improved dramatically within the past couple decades, some matter is still hard to study. Modern computers not only let us study this matter, but allow us to do it more quickly and just as accurately. The electronic structure of two rare and mostly unstudied elements, Radon (Z=86) and Francium (Z=87), has been calculated. The augmented plane wave (APW) method with local density approximation (LDA) functional as well as the linearized augmented plane wave (LAPW) method with both LDA and generalized gradient approximation (GGA) functionals were used to perform the calculations. Francium total energy calculations gave the fcc structure slightly below the bcc structure with a minimal energy difference of δE=0.33mRy. The difference found is consistent with other alkali metal total energy calculations which do not verify the bcc structure to be the ground state. Radon was predicted to be an insulator with a gap of 0.931 Ry similar to the other noble gases.

  9. Hubble Space Telescope observations of cool white dwarf stars: Detection of new species of heavy elements

    Science.gov (United States)

    Shipman, Harry; Barnhill, Maurice; Provencal, Judi; Roby, Scott; Bues, Irmela; Cordova, France; Hammond, Gordon; Hintzen, Paul; Koester, Detlev; Liebert, James

    1995-01-01

    Observations of cool white dwarf stars with the Hubble Space Telescope (HST) has uncovered a number of spectral features from previouslly unobserved species. In this paper we present the data on four cool white dwarfs. We present identifications, equivalent width measurements, and brief summaries of the significance of our findings. The four stars observed are GD 40 (DBZ3, G 74-7 (DAZ), L 745-46A (DZ), and LDS 749B (DBA). Many additional species of heavey elements were detected in GD 40 and G 74-7. In L 745-46A, while the detections are limited to Fe 1, Fe II, and Mg II, the quality of the Mg II h and K line profiles should permit a test of the line broadening theories, which are so crucial to abundance determinations. The clear detection of Mg II h and k in LDS 749 B should, once an abundance determination is made, provide a clear test of the hypothesis that the DBA stars are the result of accretion from the interstellar medium. This star contains no other clear features other than a tantalizing hint of C II 1335 with a P Cygni profile, and some expected He 1 lines.

  10. Analysis of the presence of small admixtures of heavy elements in the solar plasma by using the SAHA-S equation of state

    NARCIS (Netherlands)

    Ayukov, SV; Baturin, VA; Gryaznov, VK; Iosilevskii, IL; Starostin, AN; Fortov, VE

    2004-01-01

    The thermodynamic functions of a weakly nonideal plasma are extensively calculated for conditions typical of the depths of stars by using the SAHA-S equation of state. These calculations ensure precise analysis of the effect of the heavy-element content on adiabatic compressibility in the depths of

  11. Preventing heavy alcohol use in adolescents (PAS): cluster randomized trial of a parent and student intervention offered separately and simultaneously

    NARCIS (Netherlands)

    Koning, I.M.; Vollebergh, W.A.M.; Smit, F.; Verdurmen, J.E.E.; Eijnden, R.J.J.M. van den; Bogt, T.F.M. ter; Stattin, H.; Engels, R.C.M.E.

    2009-01-01

    Aims To evaluate the effectiveness of two preventive interventions to reduce heavy drinking in first- and second-year high school students. Design and setting Cluster randomized controlled trial using four conditions for comparing two active interventions with a control group from 152 classes of 19

  12. First spatial separation of a heavy ion isomeric beam with amultiple-reflection time-of-flight mass spectrometer

    NARCIS (Netherlands)

    Dickel, T.; Plass, W. R.; Andres, S. Ayet San; Ebert, J.; Geissel, H.; Haettner, E.; Hornung, C.; Miskun, I.; Pietri, S.; Purushothaman, S.; Reiter, M. P.; Rink, A. -K.; Scheidenberger, C.; Weick, H.; Dendooven, P.; Diwisch, M.; Greiner, F.; Heisse, F.; Knoebel, R.; Lippert, W.; Moore, I. D.; Pohjalainen, I.; Prochazka, A.; Ranjan, M.; Takechi, M.; Winfield, J. S.; Xu, X.

    2015-01-01

    Po-211 ions in the ground and isomeric states were produced via U-238 projectile fragmentation at 1000 MeV/u. The Po-211 ions were spatially separated in flight from the primary beam and other reaction products by the fragment separator FRS. The ions were energy-bunched, slowed-down and thermalized

  13. Detailed chemical abundances in NGC 5824: another metal-poor globular cluster with internal heavy element abundance variations

    Science.gov (United States)

    Roederer, Ian U.; Mateo, Mario; Bailey, John I.; Spencer, Meghin; Crane, Jeffrey D.; Shectman, Stephen A.

    2016-01-01

    We present radial velocities, stellar parameters, and detailed abundances of 39 elements derived from high-resolution spectroscopic observations of red giant stars in the luminous, metal-poor globular cluster NGC 5824. We observe 26 stars in NGC 5824 using the Michigan/Magellan Fiber System (M2FS) and two stars using the Magellan Inamori Kyocera Echelle spectrograph. We derive a mean metallicity of [Fe/H] = -1.94 ± 0.02 (statistical) ±0.10 (systematic). The metallicity dispersion of this sample of stars, 0.08 dex, is in agreement with previous work and does not exceed the expected observational errors. Previous work suggested an internal metallicity spread only when fainter samples of stars were considered, so we cannot exclude the possibility of an intrinsic metallicity dispersion in NGC 5824. The M2FS spectra reveal a large internal dispersion in [Mg/Fe], 0.28 dex, which is found in a few other luminous, metal-poor clusters. [Mg/Fe] is correlated with [O/Fe] and anticorrelated with [Na/Fe] and [Al/Fe]. There is no evidence for internal dispersion among the other α- or Fe-group abundance ratios. 25 of the 26 stars exhibit a n-capture enrichment pattern dominated by r-process nucleosynthesis ( = +0.11 ± 0.12; = -0.66 ± 0.05). Only one star shows evidence of substantial s-process enhancement ([Ba/Fe] = +0.56 ± 0.12; [Ba/Eu] = +0.38 ± 0.14), but this star does not exhibit other characteristics associated with s-process enhancement via mass transfer from a binary companion. The Pb and other heavy elements produced by the s-process suggest a time-scale of no more than a few hundred Myr for star formation and chemical enrichment, like the complex globular clusters M2, M22, and NGC 5286.

  14. Rapid Separation of Elemental Species by Fast Multicapillary Gas Chromatography with Multichannel Optical Spectrometry Detection following Headspace Solid Phase Microextraction

    Directory of Open Access Journals (Sweden)

    Jacek Giersz

    2015-05-01

    Full Text Available A method for conducting fast and efficient gas chromatography based on short multicapillaries in straight alignment combined with atomic emission detection was developed for field analysis. The strategy enables for speciation analysis of organometallic compounds. The analytes are simultaneously ethylated and preconcentrated on a solid phase microextraction (SPME fiber placed in the headspace over the sample for 25 min. The ethylated species are then completely separated and selectively quantified within 25 s under isothermal conditions. A new miniaturized speciation analyzer has been constructed and evaluated. The system consists of a GC injection port and a lab-made miniaturized GC unit directly coupled with miniaturized plasma excitation source. The emitted light is transferred via optical fiber and registered with a miniaturized charged coupled device (CCD based spectrometer. Working parameters for multicapillary column gas chromatography with atomic emission detector, including carrier gas flow rate, desorption temperature, and GC column temperature, were optimized to achieve good separation of analytes. Basic investigations of the fundamental properties of 5 cm-long multicapillary column, to evaluate its potential and limitations as a rapid separation unit, are presented. The adaptation of the technique for use with a SPME system and with a multichannel element-selective plasma-emission detector is highlighted.

  15. Design and discovery of a novel half-Heusler transparent hole conductor made of all-metallic heavy elements.

    Science.gov (United States)

    Yan, Feng; Zhang, Xiuwen; Yu, Yonggang G; Yu, Liping; Nagaraja, Arpun; Mason, Thomas O; Zunger, Alex

    2015-06-24

    Transparent conductors combine two generally contradictory physical properties, but there are numerous applications where both functionalities are crucial. Previous searches focused on doping wide-gap metal oxides. Focusing instead on the family of 18 valence electron ternary ABX compounds that consist of elements A, B and X in 1:1:1 stoichiometry, we search theoretically for electronic structures that simultaneously lead to optical transparency while accommodating intrinsic defect structures that produce uncompensated free holes. This leads to the prediction of a stable, never before synthesized TaIrGe compound made of all-metal heavy atom compound. Laboratory synthesis then found it to be stable in the predicted crystal structure and p-type transparent conductor with a strong optical absorption peak at 3.36 eV and remarkably high hole mobility of 2,730 cm(2) V(-1) s(-1) at room temperature. This methodology opens the way to future searches of transparent conductors in unexpected chemical groups.

  16. Top Quark Produced Through the Electroweak Force: Discovery Using the Matrix Element Analysis and Search for Heavy Gauge Bosons Using Boosted Decision Trees

    Energy Technology Data Exchange (ETDEWEB)

    Pangilinan, Monica [Brown Univ., Providence, RI (United States)

    2010-05-01

    The top quark produced through the electroweak channel provides a direct measurement of the Vtb element in the CKM matrix which can be viewed as a transition rate of a top quark to a bottom quark. This production channel of top quark is also sensitive to different theories beyond the Standard Model such as heavy charged gauged bosons termed W'. This thesis measures the cross section of the electroweak produced top quark using a technique based on using the matrix elements of the processes under consideration. The technique is applied to 2.3 fb-1 of data from the D0 detector. From a comparison of the matrix element discriminants between data and the signal and background model using Bayesian statistics, we measure the cross section of the top quark produced through the electroweak mechanism σ(p$\\bar{p}$ → tb + X, tqb + X) = 4.30-1.20+0.98 pb. The measured result corresponds to a 4.9σ Gaussian-equivalent significance. By combining this analysis with other analyses based on the Bayesian Neural Network (BNN) and Boosted Decision Tree (BDT) method, the measured cross section is 3.94 ± 0.88 pb with a significance of 5.0σ, resulting in the discovery of electroweak produced top quarks. Using this measured cross section and constraining |Vtb| < 1, the 95% confidence level (C.L.) lower limit is |Vtb| > 0.78. Additionally, a search is made for the production of W' using the same samples from the electroweak produced top quark. An analysis based on the BDT method is used to separate the signal from expected backgrounds. No significant excess is found and 95% C.L. upper limits on the production cross section are set for W' with masses within 600-950 GeV. For four general models of W{prime} boson production using decay channel W' → t$\\bar{p}$, the lower mass limits are the following: M(W'L with SM couplings) > 840 GeV; M(W'R) > 880 GeV or 890 GeV if the

  17. Separation of no-carrier-added {sup 66,67}Ga produced in heavy ion-induced cobalt target using alginate biopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Nayak, Dalia [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata-700064 (India); Banerjee, Anupam [University of Calcutta, 35 Ballygunge Circular Road, Kolkata-700019 (India); Lahiri, Susanta [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata-700064 (India)]. E-mail: susanta.lahiri@saha.ac.in

    2007-08-15

    Heavy ion activation of natural cobalt foil with 84 MeV {sup 12}C results in the formation of no-carrier-added (nca) {sup 66,67}As radionuclides, along with their corresponding decay products, {sup 66,67}Ge and {sup 66,67}Ga, in the matrix. Because arsenic and germanium radionuclides are short-lived, after a cooling period of 10 h only nca gallium radionuclides remain in the matrix. We attempted to separate the nca gallium radionuclides from the target matrix cobalt by biopolymeric calcium alginate (CA) and Fe-doped calcium alginate (Fe-CA) beads. A complete separation has been achieved by adsorbing {sup 66,67}Ga and a lesser amount of bulk cobalt at pH 3 on Fe-CA beads, followed by desorbing cobalt from the beads with 0.4 M NaNO{sub 2}.

  18. Electromigration in molten salts and application to isotopic separation of alkaline and alkaline-earth elements; Electromigration en sels fondus et application a la separation des isotopes des elements alcalins et alcalino-terreux

    Energy Technology Data Exchange (ETDEWEB)

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

    1969-07-01

    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{sub 2} - (CaBr{sub 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 {sup 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{sub 2} - CeBr{sub 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) [French] On a etudie la separation des isotopes des elements alcalino-terreux par electromigration a contre-courant en bromures fondus. On a etudie les conditions dans lesquelles la cathode fonctionne en electrode a brome pour des intensites les plus elevees possibles. Pour la separation du calcium, il a ete necessaire d'utiliser une chaine stable CaBr{sub 2} - (CaBr{sub 2} + KBr). Pour le baryum et le strontium, on a pu operer sur les bromures purs. On a obtenu des facteurs d

  19. Comparison of the time behavior in the separation of light and heavy materials in X-ray backscattered method as a diagnostic tool in inspection

    Energy Technology Data Exchange (ETDEWEB)

    Faezeh, Rahmani, E-mail: FRahmani@kntu.ac.ir [Department of Physics, K.N. Toosi University of Technology, Tehran (Iran, Islamic Republic of); Sepideh Sadat, Azimi [Radiation Application Department, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Esmaiel, Bayat; Vahid, Dost Mohammadi [Nuclear Science and Technology Research Institute (NSTR), Tehran (Iran, Islamic Republic of)

    2016-03-11

    X-ray backscattered method based on Compton backscattering is used in the inspection field. In contrast to transmission method, source and detectors are positioned on one side of the target, so in the situation that transmission inspection is difficult, X-ray backscattered method can be provided suitable data in the inspection field. Also, detection of hidden explosives and narcotic materials are very difficult or impossible in transmission methods. High intensity backscattered beam from light materials (low-Z), such as explosives and narcotics, in comparison to the heavy materials (high-Z), made this method as the strong technique in inspection. X-ray and gamma photons scattered by the light material (such as PE and PTFE) as well as heavy material (such as Fe and Cu) were studied using MCNPX2.6 Monte Carlo code. The results showed that rise time of pulse from light materials are slower than that of from heavy materials due to multi scattering of low energy photons in the light ones, so time expansion would occur in signals from light elements. If measurement is possible, the difference in time behavior can be used as a novel method in complementary diagnostic tool beside the use of pulse height in X-ray backscattered method.

  20. Contamination level, distribution and health risk assessment of heavy and toxic metallic and metalloid elements in a cultivated mushroom Pleurotus florida (Mont.) singer.

    Science.gov (United States)

    Khani, Rouhollah; Moudi, Maryam; Khojeh, Vahid

    2017-02-01

    There are great concentrations of toxic metallic and metalloid elements such as lead, arsenic, mercury, cadmium or silver in many species of mushrooms comparative to other fruits and vegetables. In this study, contamination with heavy and toxic metallic and metalloid elements in the cultivated mushroom of (Pleurotus florida (Mont.) Singer) is investigated. P. florida was cultivated on different substrates; wheat straw (as blank), wheat straw + pine cone, wheat straw + soybean straw and wheat straw + urea and the effects of these substrates on contamination levels of Mn, Fe, Cu, Zn, As, Cd, and Pb were analyzed. The results showed that the concentrations of essential elements (Mn, Fe, Cu, and Zn) in the target mushroom are at the typical levels. The estimated daily intakes of studied metallic and metalloid elements were below their oral reference dosage mentioned by the international regulatory bodies. Health risk index (HRI) was calculated to evaluate the consumer's health risk assessment from the metal intake that contaminated in the cultivated mushroom of P. florida on the different nutrient sources. In this study, the individual HRIs were less than 1, which indicates insignificant potential health risk associated with the consumption of target mushroom from the studied substrates. Based on the HRIs values among the toxic metallic and metalloid elements, As in the target mushroom in the substrate of the wheat straw + pine cone is the main sources of risk, and it may cause severe health problems. Thus, this study suggests that the concentrations of heavy and toxic elements should be periodically monitored in cultivated mushrooms.

  1. 2nd International Symposium on Fundamental Aspects of Rare-earth Elements Mining and Separation and Modern Materials Engineering (REES-2015)

    Science.gov (United States)

    Tavadyan, Levon, Prof; Sachkov, Viktor, Prof; Godymchuk, Anna, Dr.; Bogdan, Anna

    2016-01-01

    The 2nd International Symposium «Fundamental Aspects of Rare-earth Elements Mining and Separation and Modern Materials Engineering» (REES2015) was jointly organized by Tomsk State University (Russia), National Academy of Science (Armenia), Shenyang Polytechnic University (China), Moscow Institute of Physics and Engineering (Russia), Siberian Physical-technical Institute (Russia), and Tomsk Polytechnic University (Russia) in September, 7-15, 2015, Belokuriha, Russia. The Symposium provided a high quality of presentations and gathered engineers, scientists, academicians, and young researchers working in the field of rare and rare earth elements mining, modification, separation, elaboration and application, in order to facilitate aggregation and sharing interests and results for a better collaboration and activity visibility. The goal of the REES2015 was to bring researchers and practitioners together to share the latest knowledge on rare and rare earth elements technologies. The Symposium was aimed at presenting new trends in rare and rare earth elements mining, research and separation and recent achievements in advanced materials elaboration and developments for different purposes, as well as strengthening the already existing contacts between manufactures, highly-qualified specialists and young scientists. The topics of the REES2015 were: (1) Problems of extraction and separation of rare and rare earth elements; (2) Methods and approaches to the separation and isolation of rare and rare earth elements with ultra-high purity; (3) Industrial technologies of production and separation of rare and rare earth elements; (4) Economic aspects in technology of rare and rare earth elements; and (5) Rare and rare earth based materials (application in metallurgy, catalysis, medicine, optoelectronics, etc.). We want to thank the Organizing Committee, the Universities and Sponsors supporting the Symposium, and everyone who contributed to the organization of the event and to

  2. Gas-filled separators - An overview

    CERN Document Server

    Leino, M

    2003-01-01

    Gas-filled recoil separators have been used in nuclear physics studies since the early fifties. Most notably, they have found use in the separation of evaporation residues of heavy and very heavy elements from unwanted background. Gas-filled separators, alone or coupled to a detector array, offer an efficient, fast, compact and relatively inexpensive solution for nuclear structure studies. A new application is the use of a gas-filled device as a pre-separator in the study of chemical properties of the heaviest elements. Other uses include systematic study of fusion evaporation cross sections and accelerator mass spectrometry. In this contribution, an overview on gas-filled recoil separators, their characteristics, fields of application and possible future developments is given.

  3. First spatial separation of a heavy ion isomeric beam with a multiple-reflection time-of-flight mass spectrometer

    Directory of Open Access Journals (Sweden)

    T. Dickel

    2015-05-01

    Full Text Available 211Po ions in the ground and isomeric states were produced via 238U projectile fragmentation at 1000 MeV/u. The 211Po ions were spatially separated in flight from the primary beam and other reaction products by the fragment separator FRS. The ions were energy-bunched, slowed-down and thermalized in a gas-filled cryogenic stopping cell (CSC. They were then extracted from the CSC and injected into a high-resolution multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS. The excitation energy of the isomer and, for the first time, the isomeric-to-ground state ratio were determined from the measured mass spectrum. In the subsequent experimental step, the isomers were spatially separated from the ions in the ground state by an ion deflector and finally collected with a silicon detector for decay spectroscopy. This pioneering experimental result opens up unique perspectives for isomer-resolved studies. With this versatile experimental method new isomers with half-lives longer than a few milliseconds can be discovered and their decay properties can be measured with highest sensitivity and selectivity. These experiments can be extended to studies with isomeric beams in nuclear reactions.

  4. First spatial separation of a heavy ion isomeric beam with a multiple-reflection time-of-flight mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Dickel, T. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Plaß, W.R., E-mail: Wolfgang.R.Plass@exp2.physik.uni-giessen.de [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Ayet San Andres, S. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Ebert, J. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen (Germany); Geissel, H.; Haettner, E. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Hornung, C. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen (Germany); Miskun, I. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Pietri, S.; Purushothaman, S. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); and others

    2015-05-11

    {sup 211}Po ions in the ground and isomeric states were produced via {sup 238}U projectile fragmentation at 1000 MeV/u. The {sup 211}Po ions were spatially separated in flight from the primary beam and other reaction products by the fragment separator FRS. The ions were energy-bunched, slowed-down and thermalized in a gas-filled cryogenic stopping cell (CSC). They were then extracted from the CSC and injected into a high-resolution multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS). The excitation energy of the isomer and, for the first time, the isomeric-to-ground state ratio were determined from the measured mass spectrum. In the subsequent experimental step, the isomers were spatially separated from the ions in the ground state by an ion deflector and finally collected with a silicon detector for decay spectroscopy. This pioneering experimental result opens up unique perspectives for isomer-resolved studies. With this versatile experimental method new isomers with half-lives longer than a few milliseconds can be discovered and their decay properties can be measured with highest sensitivity and selectivity. These experiments can be extended to studies with isomeric beams in nuclear reactions.

  5. First spatial separation of a heavy ion isomeric beam with a multiple-reflection time-of-flight mass spectrometer

    Science.gov (United States)

    Dickel, T.; Plaß, W. R.; Ayet San Andres, S.; Ebert, J.; Geissel, H.; Haettner, E.; Hornung, C.; Miskun, I.; Pietri, S.; Purushothaman, S.; Reiter, M. P.; Rink, A.-K.; Scheidenberger, C.; Weick, H.; Dendooven, P.; Diwisch, M.; Greiner, F.; Heiße, F.; Knöbel, R.; Lippert, W.; Moore, I. D.; Pohjalainen, I.; Prochazka, A.; Ranjan, M.; Takechi, M.; Winfield, J. S.; Xu, X.

    2015-05-01

    211Po ions in the ground and isomeric states were produced via 238U projectile fragmentation at 1000 MeV/u. The 211Po ions were spatially separated in flight from the primary beam and other reaction products by the fragment separator FRS. The ions were energy-bunched, slowed-down and thermalized in a gas-filled cryogenic stopping cell (CSC). They were then extracted from the CSC and injected into a high-resolution multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS). The excitation energy of the isomer and, for the first time, the isomeric-to-ground state ratio were determined from the measured mass spectrum. In the subsequent experimental step, the isomers were spatially separated from the ions in the ground state by an ion deflector and finally collected with a silicon detector for decay spectroscopy. This pioneering experimental result opens up unique perspectives for isomer-resolved studies. With this versatile experimental method new isomers with half-lives longer than a few milliseconds can be discovered and their decay properties can be measured with highest sensitivity and selectivity. These experiments can be extended to studies with isomeric beams in nuclear reactions.

  6. Grain boundary engineering in sintered Nd-Fe-B permanent magnets for efficient utilization of heavy rare earth elements

    Energy Technology Data Exchange (ETDEWEB)

    Loewe, Konrad

    2016-10-18

    The first part of the thesis investigates the diffusion of rare-earth (RE) elements in commercial sintered Nd-Fe-B based permanent magnets. A strong temperature dependence of the diffusion distance and resulting change in magnetic properties were found. A maximum increase in coercivity of ∼+350 kA/m using a Dy diffusion source occurred at the optimum annealing temperature of 900 C. After annealing for 6 h at this temperature, a Dy diffusion distance of about 4 mm has been observed with a scanning Hall probe. Consequently, the maximum thickness of grain boundary diffusion processed magnets with homogeneous properties is also only a few mm. The microstructural changes in the magnets after diffusion were investigated by electron microscopy coupled with electron probe microanalysis. It was found that the diffusion of Dy into sintered Nd-Fe-B permanent magnets occurs along the grain boundary phases, which is in accordance with previous studies. A partial melting of the Nd-Fe-B grains during the annealing process lead to the formation of so - called (Nd,Dy)-Fe-B shells at the outer part of the grains. These shells are μm thick at the immediate surface of the magnet and become thinner with increasing diffusion distance towards the center of the bulk. With scanning transmission electron microscopy coupled with electron probe analysis a Dy content of about 1 at.% was found in a shell located about 1.5 mm away from the surface of the magnet. The evaluation of diffusion speeds of Dy and other RE (Tb, Ce, Gd) in Nd-Fe-B magnets showed that Tb diffuses significantly faster than Dy, and Ce slightly slower than Dy, which is attributed to differences in the respective phase diagrams. The addition of Gd to the grain boundaries has an adverse effect on coercivity. Exemplary of the heavy rare earth element Tb, the nano - scale elemental distribution around the grain boundaries after the diffusion process was visualized with high resolution scanning transmission electron microscopy

  7. Distribution of rare earth elements and heavy metals in the surficial sediments of the Himalayan river system

    National Research Council Canada - National Science Library

    Ramesh, R; Ramanathan, Al; Ramesh, S; Purvaja, R; Subramanian, V

    2000-01-01

    .... REEs and heavy metals (V, Pb, Cr, Co, Ag, Zn, Cd, Ni) were analyzed from the suspended sediments of Ganges and surficial sediments of Yamuna, Brahmaputra, Jamuna, Padma and Meghna, using VG Thermal Ionization Mass Spectrometer...

  8. Carrier element-free coprecipitation (CEFC) method for the separation, preconcentration and speciation of chromium using an isatin derivative.

    Science.gov (United States)

    Bulut, Volkan Numan; Ozdes, Duygu; Bekircan, Olcay; Gundogdu, Ali; Duran, Celal; Soylak, Mustafa

    2009-01-19

    A new, simple, rapid and sensitive separation, preconcentration and speciation procedure for chromium in environmental liquid and solid samples has been established. The present speciation procedure for Cr(III) and Cr(VI) is based on combination of carrier element-free coprecipitation (CEFC) and flame atomic absorption spectrometric (FAAS) determinations. In this method a newly synthesized organic coprecipitant, 5-chloro-3-[4-(trifluoromethoxy) phenylimino]indolin-2-one (CFMEPI), was used without adding any carrier element for coprecipitation of chromium(III). After reduction of chromium(VI) by concentrated H(2)SO(4) and ethanol, the procedure was applied for the determination of total chromium. Chromium(VI) was calculated as the difference between the amount of total chromium and chromium(III). The optimum conditions for coprecipitation and speciation processes were investigated on several commonly tested experimental parameters, such as pH of the solution, amount of coprecipitant, sample volume, etc. No considerable interference was observed from the other investigated anions and cations, which may be found in natural water samples. The preconcentration factor was found to be 40. The detection limit for chromium(III) corresponding to three times the standard deviation of the blank (N=10) was found 0.7 microg L(-1). The present procedure was successfully applied for speciation of chromium in several liquid and solid environmental samples. In order to support the accuracy of the method, the certified reference materials (CRM-TMDW-500 Drinking Water and CRM-SA-C Sandy Soil C) were analyzed, and standard APDC-MIBK liquid-liquid extraction method was performed. The results obtained were in good agreement with the certified values.

  9. Finite-element model to predict roll-separation force and defects during rolling of U-10Mo alloys

    Science.gov (United States)

    Soulami, Ayoub; Burkes, Douglas E.; Joshi, Vineet V.; Lavender, Curt A.; Paxton, Dean

    2017-10-01

    A major goal of the Convert Program of the U.S. Department of Energy's National Nuclear Security Administration (DOE/NNSA) is to enable high-performance research reactors to operate with low-enriched uranium rather than the high-enriched uranium currently used. To this end, uranium alloyed with 10 wt% molybdenum (U-10Mo) represents an ideal candidate because of its stable gamma phase, low neutron caption cross section, acceptable swelling response, and predictable irradiation behavior. However, because of the complexities of the fuel design and the need for rolled monolithic U-10Mo foils, new developments in processing and fabrication are necessary. This study used a finite-element code, LS-DYNA, as a predictive tool to optimize the rolling process. Simulations of the hot rolling of U-10Mo coupons encapsulated in low-carbon steel were 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. The study reported here discussed various attributes of the rolled coupons revealed by the model (e.g., waviness and thickness non-uniformity like dog-boning). To investigate the influence of the cladding material on these rolling defects, other cases were simulated: hot rolling with alternative can materials, namely, 304 stainless steel and Zircaloy-2, and bare-rolling. Simulation results demonstrated that reducing the mismatch in strength between the coupon and can material improves the quality of the rolled sheet. Bare-rolling simulation results showed a defect-free rolled coupon. The finite-element model developed and presented in this study can be used to conduct parametric studies of several process parameters (e.g., rolling speed, roll diameter, can material, and reduction).

  10. Improving the Quality of Mixed Recycled Coarse Aggregates from Construction and Demolition Waste Using Heavy Media Separation with Fe3O4 Suspension

    Directory of Open Access Journals (Sweden)

    Heonchan Kang

    2017-01-01

    Full Text Available The primary objectives of this study are to investigate the feasibility of a heavy media separation process with magnetite (Fe3O4 suspension for upgrading the quality of mixed recycled coarse aggregates from construction and demolition waste (CDW in Korea and to determine a range of effective operating density of Fe3O4 suspension for producing high-quality RCA acceptable to structural concrete applications. For the purposes, six 200 kg recycled coarse aggregates (RCAs samples were collected from a conventional recycling plant in Korea. Subsequently, the samples were processed by a heavy media separation process using Fe3O4 suspensions with various densities from 2.65 g/cm3 to 2.40 g/cm3 with an interval of 0.05 g/cm3. Next, a series of tests was performed in the laboratory to evaluate properties of finished sink and float products from the HMS processes, including oven-dry density, absorption capacity, and physical durability. Furthermore, compressive strength of concrete cylinders (150 mm by 300 mm made of the finished sink products from Fe3O4 suspensions with three different densities (2.4, 2.5, and 2.6 g/cm3 was tested in this study. As a result, it was demonstrated that the HMS process using Fe3O4 suspension with a density ranging between 2.40 and 2.65 g/cm3 was effective for upgrading mixed CDW RCAs in Korea to high-quality RCAs acceptable for structural concrete applications.

  11. Finite-element model to predict roll-separation force and defects during rolling of U-10Mo alloys

    Energy Technology Data Exchange (ETDEWEB)

    Soulami, Ayoub; Burkes, Douglas E.; Joshi, Vineet V.; Lavender, Curt A.; Paxton, Dean

    2017-10-01

    This study used a finite element code, LSDYNA, as a predictive tool to optimize the rolling process. Simulations of the hot rolling of U-10Mo coupons encapsulated in low-carbon steel were 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. The study reported here discussed various attributes of the rolled coupons revealed by the model (e.g., waviness and thickness non-uniformity like dog boning). To investigate the influence of the cladding material on these rolling defects, other cases were simulated:  hot rolling with alternative can materials, namely, 304 stainless steel and Zircaloy-2, and bare-rolling.

  12. A Novel Synthesis Routine for Woodwardite and Its Affinity towards Light (La, Ce, Nd) and Heavy (Gd and Y) Rare Earth Elements.

    Science.gov (United States)

    Consani, Sirio; Balić-Žunić, Tonci; Cardinale, Anna Maria; Sgroi, Walter; Giuli, Gabriele; Carbone, Cristina

    2018-01-14

    A synthetic Cu-Al-SO₄ layered double hydroxide (LDH), analogue to the mineral woodwardite [Cu1-xAlx(SO₄)x/2(OH)₂·nH₂O], with x rare earth elements (LREEs) (La, Ce, and Nd) and heavy rare earth elements (HREEs) (Gd and Y) in order to test the affinity of the Cu-Al-SO₄ LDH to the incorporation of REEs. The concentration of rare earth elements (REEs) in the solid fraction was in the range of 3.5-8 wt %. The results showed a good affinity for HREE and Nd, especially for materials synthesised at pH 10.0, whereas the affinities for Ce and La were much lower or non-existent. The thermal decomposition of the REE-doped materials generates a mixture of Cu, Al, and REE oxides, making them interesting as precursors in REE oxide synthesis.

  13. IRiS—Exploring new frontiers in neutron-rich isotopes of the heaviest elements with a new Inelastic Reaction Isotope Separator

    Science.gov (United States)

    Dvorak, J.; Block, M.; Düllmann, Ch. E.; Heinz, S.; Herzberg, R.-D.; Schädel, M.

    2011-10-01

    A dedicated Inelastic Reaction Isotope Separator (IRiS) for multi-nucleon transfer products will be designed and installed at GSI. Research at IRiS will focus on the investigation of new neutron-rich isotopes of the heaviest elements, study of which will advance various research fields, such as nuclear chemistry, nuclear and atomic physics, as well as nuclear astrophysics. The scientific motivation for this project and the alternative design options for the separator and its main components are discussed.

  14. [Application of ICP-MS to detection of mineral elements and heavy metals in transgenic cotton seeds].

    Science.gov (United States)

    Rui, Yu-Kui; Zhang, Fu-Suo; Wang, Zheng-Rui

    2008-01-01

    With the rapid development of transgenic cotton, people begin to focus on its physiology and ecology. The present paper studied the contents of heavy metals and microelements in transgenic cotton seeds by ICP-MS/ICP-AES. The results showed that the content of most microelements detected in transgenic cotton seeds, B, Na, Si, P, K, Ca, Mn, Co, Ni, Zn, Se and Mo was lower than that in regular cotton seeds, except Mg, Fe and Cu. And the content of most heavy metals detected in transgenic cotton seeds, Al, As, Cd, Sb, Tl, Pb and Bi, was higher than that in regular cotton seeds, except Cr and Hg. All the data showed that the accumulation of heavy metals and microelements in transgenic cotton seeds is disadvantageous to itself.

  15. The new confocal heavy ion microprobe beamline at ANSTO: The first microprobe resolution tests and applications for elemental imaging and analysis

    Science.gov (United States)

    Pastuovic, Z.; Siegele, R.; Cohen, D. D.; Mann, M.; Ionescu, M.; Button, D.; Long, S.

    2017-08-01

    The Centre for Accelerator Science facility at ANSTO has been expanded with the new NEC 6 MV ;SIRIUS; accelerator system in 2015. In this paper we present a detailed description of the new nuclear microprobe-Confocal Heavy Ion Micro-Probe (CHIMP) together with results of the microprobe resolution testing and the elemental analysis performed on typical samples of mineral ore deposits and hyper-accumulating plants regularly measured at ANSTO. The CHIMP focusing and scanning systems are based on the OM-150 Oxford quadrupole triplet and the OM-26 separated scan-coil doublet configurations. A maximum ion rigidity of 38.9 amu-MeV was determined for the following nuclear microprobe configuration: the distance from object aperture to collimating slits of 5890 mm, the working distance of 165 mm and the lens bore diameter of 11 mm. The overall distance from the object to the image plane is 7138 mm. The CHIMP beamline has been tested with the 3 MeV H+ and 6 MeV He2+ ion beams. The settings of the object and collimating apertures have been optimized using the WinTRAX simulation code for calculation of the optimum acceptance settings in order to obtain the highest possible ion current for beam spot sizes of 1 μm and 5 μm. For optimized aperture settings of the CHIMP the beam brightness was measured to be ∼0.9 pA μm-2 mrad-2 for 3 MeV H+ ions, while the brightness of ∼0.4 pA μm-2 mrad-2 was measured for 6 MeV He2+ ions. The smallest beam sizes were achieved using a microbeam with reduced particle rate of 1000 Hz passing through the object slit apertures several micrometers wide. Under these conditions a spatial resolution of ∼0.6 μm × 1.5 μm for 3 MeV H+ and ∼1.8 μm × 1.8 μm for 6 MeV He2+ microbeams in horizontal (and vertical) dimension has been achieved. The beam sizes were verified using STIM imaging on 2000 and 1000 mesh Cu electron microscope grids.

  16. On the concentration and separation of the trace-elements fe, cu, zn, mn, pb, mo and co : Paper chromatography

    NARCIS (Netherlands)

    Erkelens, P.C. van

    1961-01-01

    Paper chromatographic separations are described by which the minor constituents of biological ashes are separated either into: (Pb) - Mn - Co - (Pb) - Cu - Fe, Mo, Zn; or into: Cu, Mn, Co - Pb - Fe - Mo - Zn.

  17. Application of a space-time CE/SE (Conversation Element/Solution Element) method to the numerical solution of chromatographic separation processes

    DEFF Research Database (Denmark)

    For solving partial differential equations (or distributed dynamic systems), the method of lines (MOL) and the space-time conservation element and solution element (CE/SE) method are compared in terms of computational efficiency, solution accuracy and stability. Several representative examples....... It is concluded that the CE/SE method is adequate to capturing shocks in PDEs but for diffusion-dominated stiff PDEs, the MOL with an ODE time integrator is complementary to the CE/SE method....

  18. New X-ray microprobe system for trace heavy element analysis using ultraprecise X-ray mirror optics of long working distance

    Energy Technology Data Exchange (ETDEWEB)

    Terada, Yasuko, E-mail: yterada@spring8.or.j [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Yumoto, Hirokatsu; Takeuchi, Akihisa; Suzuki, Yoshio [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Yamauchi, Kazuto [Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Uruga, Tomoya [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)

    2010-05-01

    A new X-ray microprobe system for trace heavy element analysis using ultraprecise X-ray mirror optics of 300 mm long working distance has been developed at beamline 37XU of SPring-8. A focusing test has been performed in the X-ray energy range 20-37.7 keV. A focused beam size of 1.3 mum (V)x1.5 mum (H) has been achieved at an X-ray energy of 30 keV, and a total photon flux of the focused beam was about 2.7x10{sup 10} photons/s. Micro-X-ray fluorescence (mu-XRF) analysis of eggplant roots has been carried out using the developed microprobe. It is clearly observed in the XRF images that cadmium is highly accumulated in the endodermis, exodermis and epidermis of roots. This study demonstrates the potential of scanning microscopy for heavy elements analysis in the high-energy X-ray region.

  19. Separation and characterization of magnetic fractions from waste-to-energy bottom ash with an emphasis on the leachability of heavy metals.

    Science.gov (United States)

    Wei, Yunmei; Mei, Xiaoxia; Shi, Dezhi; Liu, Guotao; Li, Li; Shimaoka, Takayuki

    2017-06-01

    Magnetic fractions were extracted from pulverized waste-to-energy (WTE) bottom ashes using a combined wet-dry extraction method. The resulting magnetic and non-magnetic fractions were subjected to compositional, mineralogical, and redox state analyses by X-ray diffraction (XRD), X-ray fluorescence, and X-ray photoelectron spectroscopy (XPS), respectively. The distribution and leaching toxicity of heavy metals were assessed to evaluate potential effects on the environment. Compositional analyses revealed that Fe accounted for 35% of the magnetic fraction of pulverized ashes, which was approximately seven times that of the raw ash. In addition to Fe, elemental Ni, Mn, and Cr were also significantly enriched in the magnetic fractions. The mineralogical analysis determined that Fe was primarily present as hematite and magnetite, and metallic iron was also identified in the magnetic fraction samples. The XPS analysis further proved the existence of zero-valence Fe. However, a significant amount of Fe remained in the non-magnetic fractions, which could partially be ascribed to the intergrowth structure of the various minerals. The elevated concentrations of toxicity characteristic leaching procedure (TCLP)-extracted Mn, Ni, Cr, Cu, Pb, and Zn were primarily ascribed to the lower buffering capability of the magnetic fractions, with the enrichment of Mn, Ni, and Cr in the magnetic fractions also contributing to this elevation.

  20. HELAC-Onia 2.0: an upgraded matrix-element and event generator for heavy quarkonium physics

    CERN Document Server

    Shao, Hua-Sheng

    2016-01-01

    We present an upgraded version (denoted as version 2.0) of the program HELAC-Onia for the automated computation of heavy-quarkonium helicity amplitudes within non-relativistic QCD framework. The new code has been designed to include many new and useful features for practical phenomenological simulations. It is designed for job submissions under cluster enviroment for parallel computations via Python scripts. We have interfaced HELAC-Onia to the parton shower Monte Carlo programs Pythia 8 and QEDPS to take into account the parton-shower effects. Moreover, the decay module guarantees that the program can perform the spin-entangled (cascade-)decay of heavy quarkonium after its generation. We have also implemented a reweighting method to automatically estimate the uncertainties from renormalization and/or factorization scales as well as parton-distribution functions to weighted or unweighted events. A futher update is the possiblity to generate one-dimensional or two-dimensional plots encoded in the analysis file...

  1. Heavy-ion double charge exchange reactions: A tool toward 0 νββ nuclear matrix elements

    Energy Technology Data Exchange (ETDEWEB)

    Cappuzzello, F.; Bondi, M. [Universita di Catania, Dipartimento di Fisica e Astronomia, Catania (Italy); INFN, Laboratori Nazionali del Sud, Catania (Italy); Cavallaro, M.; Agodi, C.; Carbone, D.; Cunsolo, A. [INFN, Laboratori Nazionali del Sud, Catania (Italy); Foti, A. [Universita di Catania, Dipartimento di Fisica e Astronomia, Catania (Italy); INFN, Sezione di Catania, Catania (Italy)

    2015-11-15

    The knowledge of the nuclear matrix elements for the neutrinoless double beta decay is fundamental for neutrino physics. In this paper, an innovative technique to extract information on the nuclear matrix elements by measuring the cross section of a double charge exchange nuclear reaction is proposed. The basic point is that the initial- and final-state wave functions in the two processes are the same and the transition operators are similar. The double charge exchange cross sections can be factorized in a nuclear structure term containing the matrix elements and a nuclear reaction factor. First pioneering experimental results for the {sup 40}Ca({sup 18}O,{sup 18}Ne){sup 40}Ar reaction at 270 MeV incident energy show that such cross section factorization reasonably holds for the crucial 0{sup +} → 0{sup +} transition to {sup 40}Ar{sub gs}, at least at very forward angles. (orig.)

  2. Influence of N-phthaloyl chitosan on poly (ether imide) ultrafiltration membranes and its application in biomolecules and toxic heavy metal ion separation and their antifouling properties

    Science.gov (United States)

    Kanagaraj, P.; Nagendran, A.; Rana, D.; Matsuura, T.; Neelakandan, S.; Karthikkumar, T.; Muthumeenal, A.

    2015-02-01

    N-phthaloyl chitosan (NPHCs), which could be dissolved in various organic solvents, is synthesized for the modification of poly (ether imide) (PEI) ultrafiltration membrane. Blend membrane with 2 wt% NPHCs exhibited higher pure water flux (112.2 l m-2 h-1), higher water content (63.4%) and lower hydraulic resistance (3 kPa/l m-2 h-1). The top surface morphology of the control PEI membrane changed from a dense surface to visible pores with the increase in NPHCs concentration. The surface roughness of PEI membranes increased with an increase in NPHCs concentration in the casting solution. Application studies were carried out to find the rejection and permeate flux of proteins such as bovine serum albumin (BSA), egg albumin (EA), pepsin and trypsin and toxic heavy metal ions such as Cr(III), Zn(II), Cd(II) and Pb(II). The result shows that the flux and separation performances are dependent upon the content of NPHCs. Furthermore, the blend membranes were subjected to the determination of pore statistics and MWCO. It was found that the blending of NPHCs into the PEI membrane had a visible effect upon MWCO and pore size. The significant effect of hydrophilicity of NPHCs on the fouling of PEI/NPHCs blend membranes by BSA was also discussed. It was found that the blend membranes with 2 wt% NPHCs content had a higher FRR (88.6%), higher reversible fouling (23.7%) and lower irreversible fouling (11.4%) which explained their improved antifouling properties. Thus, the modified chitosan proved to play an important role in the improvement of UF membrane performance.

  3. Characterization of size, morphology and elemental composition of nano-, submicron, and micron particles of street dust separated using field-flow fractionation in a rotating coiled column.

    Science.gov (United States)

    Fedotov, Petr S; Ermolin, Mikhail S; Karandashev, Vasily K; Ladonin, Dmitry V

    2014-12-01

    For the first time, nano- and submicron particles of street dust have been separated, weighted, and analyzed. A novel technique, sedimentation field-flow fractionation in a rotating coiled column, was applied to the fractionation of dust samples with water being used as a carrier fluid. The size and morphology of particles in the separated fractions were characterized by electronic microscopy before digestion and the determination of the concentration of elements by ICP-AES and ICP-MS. The elements that may be of anthropogenic origin (Zn, Cr, Ni, Cu, Cd, Sn, Pb) were found to concentrate mainly in particles present only about 0.1 mass% of the sample they are of special concern due to their increased mobility and ability to penetrate into the deepest alveolar area of the lungs. For rare earth elements (La, Ce, Pr, Nd, Sm) that are evidently of natural source and may be found in soil minerals, in contrary, higher concentrations were observed in large particles (10-100 μm). Sc was an exception that needs further studies. The proposed approach to the fractionation and analysis of nano-, submicron, and micron particles can be a powerful tool for risk assessment related to toxic elements in dust, ash, and other particulate environmental samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Concentration of heavy metals and trace elements in soils, waters and vegetables and assessment of health risk in the vicinity of a lignite-fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    Noli, Fotini, E-mail: noli@chem.auth.gr; Tsamos, Panagiotis, E-mail: pktsamos@chem.auth.gr

    2016-09-01

    The pollution of agricultural soils, waters and products in the regions of lignite mines and fired power plants is of great importance. The concentration of As, Βa, Co, Cr, Sr, Sc, Th, U, Zn in soils and waters in the vicinity of a lignite-fired power plant in Northern Greece was determined using Instrumental Neutron Activation Analysis. The determination frequency was every three months during a period of one year in order to evaluate the seasonal impact of the pollution to the environment. Measurements were performed in three locations around the lignite mine as well as in one reference location at a certain distance from the mine. The results, which exhibited a slight seasonal variation, were compared, where possible, with literature values from other countries. The obtained data in most of the cases did not exceed the normal levels and indicated that the investigated area was only slightly contaminated. The concentration of heavy and trace metals was also measured in three common garden crops (tomato, cucumber and parsley) grown in this area. The calculated transfer factors (TF) from soil to vegetables and health risk quotients (HQ) do not denote a health risk. - Highlights: • Seasonal variation of heavy metals concentrations in soils and waters in a lignite mining area. • The elevated concentrations detected by NAA indicating minor contamination of the studied area. • Determination of minor and trace elements in vegetables. • The transfer factors and health risk quotients indicating a possible slight contamination in the area.

  5. Levels of rare earth elements, heavy metals and uranium in a population living in Baiyun Obo, Inner Mongolia, China: a pilot study.

    Science.gov (United States)

    Hao, Zhe; Li, Yonghua; Li, Hairong; Wei, Binggan; Liao, Xiaoyong; Liang, Tao; Yu, Jiangping

    2015-06-01

    The Baiyun Obo deposit is the world's largest rare earth elements (REE) deposit. We aimed to investigate levels of REE, heavy metals (HMs) and uranium (U) based on morning urine samples in a population in Baiyun Obo and to assess the possible influence of rare earth mining processes on human exposure. In the mining area, elevated levels were found for the sum of the concentrations of light REE (LREE) and heavy REE (HREE) with mean values at 3.453 and 1.151 μg g(-1) creatinine, which were significantly higher than those in the control area. Concentrations of HMs and U in the population increased concomitantly with increasing REE levels. The results revealed that besides REE, HMs and U were produced with REE exploitation. Gender, age, educational level, alcohol and smoking habit were major factors contributing to inter-individual variation. Males were more exposed to these metals than females. Concentrations in people in the senior age group and those with only primary education were low. Drinking and smoking were associated with the levels of LREE, Cr, Cu, Cd and Pb in morning urine. Hence this study provides basic and useful information when addressing public and environmental health challenges in the areas where REE are mined and processed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. On the concentration and separation of the trace-elements Fe, Cu, Zn, Mn, Pb, Mo and Co : Solvent Extraction

    NARCIS (Netherlands)

    Erkelens, P.C. van

    1961-01-01

    Extractions with acetylacetone and diethyldithiocarbamate are described. Through the successive application of these reagents the constituents of biological ashes are concentrated and separated into the groups: (1) MoO4-2, (2) Fe+3, Cu+2 , (3) Mn+2, (4) Zn+2, (5) Pb+2, (6) Co+3 and (7)Na+, K+, Ca+2,

  7. 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.)

  8. 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).

    Science.gov (United States)

    Cairns, Warren R L; De Boni, Antonella; Cozzi, Giulio; Asti, Massimo; Borla, Edoardo Merlone; Parussa, Flavio; Moretto, Ezio; Cescon, Paolo; Boutron, Claude; Gabrieli, Jacopo; Barbante, Carlo

    2011-03-01

    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(-1) for Pd, 0.4 ng g(-1) for Rh and 4.3 ng g(-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(-1) for Rh to 70.5 ng km(-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.

  9. [Three-dimensional finite element analysis of stress distribution about abutments periodontal membranes of separated removable partial denture and conical telescope].

    Science.gov (United States)

    Tang, Ying; Wang, Min; Luo, Yun; Man, Yi

    2009-10-01

    To investigate and compare the stress of edentulous mucosa and periodontal membranes of the abutments under vertical loads for separated removable partial denture or conical telescope denture. One patient who had lost the second premolar and the first molar on the upper jaw and had I mobile abutments was chosen in the study. Two precise three dimensional finite element models were constructed by using screw CT image reconstruction technique and Materialise Mimics, Pro/Engineer WF 2.0, ANSYS Workbench software. Vertical forces were loaded on the two models. Then comparing and analyzing the von Mises stress distribution of the edentulous mucosa and the periodontal membranes of abutments between the separate removable partial denture and conical telescope denture in the software of ANSYS Workbench. The von Mises stress values of the edentulous mucosa of separate removable partial denture were larger than that of the conical telescope denture. The von Mises stress values of abutments periodontal membranes of separate removable partial denture were lower than that of conical telescope denture. Under vertical loads, compare with conical telescope denture, the separate removable partial denture can protect the abutments.

  10. 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.

  11. Separation of rare earth by column chromatography using organic resins XAD/DEPHA

    Energy Technology Data Exchange (ETDEWEB)

    Zini, J.; Ferreira, J.C.; Bergamaschi, V.S.; Santos, I.; Carvalho, F.M.S., E-mail: jcferrei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (CCCH/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Celulas a Combustivel e Hidrogenio

    2013-07-01

    The designation of light and heavy rare earth was used the fractionation used in separation processes. In this study the process of separation of rare earth, in groups, by chromatographic column consisting in fixing of cations these elements in an organic resin Amberlite XAD16 functionalized with the extracting agent DEPHA and another portion functionalized with a mixture of extractors DEPHA/TOP. The preparation of these resins was performed in two forms, one directly as the extracting agent to the resin and the other to be used in ethyl alcohol. Conditioned resins were introduced in chromatographic columns in separation of groups, light and heavy, using a standard solution of cerium nitrate and standard solution of holmium nitrate groups to represent light and heavy respectively. The characterization technique used to identify the rare earth elements was Spectrometry X-Ray Fluorescence (XRF). The results using the technique of chromatography were satisfactory, obtaining 100% separation of the elements. (author)

  12. Batch leaching tests of motherboards to assess environmental contamination by bromine, platinum group elements and other selected heavy metals.

    Science.gov (United States)

    Almeida, César; Grosselli, Melina; González, Patricia; Martínez, Dante; Gil, Raúl

    2016-02-01

    In this study, a batch leaching test was executed to evaluate the toxicity associated with chemicals contained in motherboards. The leaching solutions used were distilled water, nitric acid, acetic acid and synthetic acid rain solution. A total of 21 elements including Ag, As, Au, Br, Cd, Co, Cr, Cu, Hf, Ir, Mn, Ni, Os, Pb, Pd, Pt, Rd, Rh, Se, U and Zn were analyzed. In this study, the pH values of all the leachates fell within the range of 2.33-4.88. The highest concentrations of metals were obtained from the acid rain solution, whilst the maximum value of bromine was achieved with solution of acetic acid. Appreciable concentrations of platinum group elements were detected with concentrations around 3.45, 1.43, 1.21 and 22.19 µg L(-1) for Ir, Pd, Pt and Rh, respectively. The different leaching of the motherboards revealed the predominant presence of the toxic substances in the leached from the e-waste. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Study the chemical composition and biological outcomes resulting from the interaction of the hormone adrenaline with heavy elements: Infrared, Raman, electronic, 1H NMR, XRD and SEM studies

    Science.gov (United States)

    Ibrahim, Omar B.; Mohamed, Mahmoud A.; Refat, Moamen S.

    2014-01-01

    Heavy metal adrenaline complexes formed from the reaction of adrenaline with Al3+, Zn2+, Sn2+, Sb3+, Pb2+and Bi3+ ions in methanolic solvent at 60 °C. The final reaction products have been isolated and characterization using elemental analyses (% of carbon, hydrogen and nitrogen), conductivity measurements, mid infrared, Raman laser, UV-Vis, 1H NMR spectra, X-ray powder diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy (EDX). Upon the spectroscopic, conductivity and elemental analyses, the stoichiometric reactions indicated that the data obtained refer to 1:2 (M:L) for Zn2+, Sn2+, Pb2+and Bi3+ complexes [Zn(Adr)2(Cl)2], [Sn(Adr)2]Cl2, [Pb(Adr)2](NO3)2 and [Bi(Adr)2(Cl)2]Cl, while the molar ratio 1:3 (M:L) for Al3+ and Sb3+ with formulas [Al(Adr)3](NO3)3 and [Sb(Adr)3]Cl3. The infrared and Raman laser spectra interpreted the mode of interactions which associated through the two phenolic groups of catechol moiety. The adrenaline chelates have been screened for their in vitro antibacterial activity against four bacteria, Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and two strains of fungus (Aspergillus flavus and Candida albicans). The metal chelates were shown to possess more antibacterial and antifungal activities than the free adrenaline chelate.

  14. Airborne heavy metal pollution and its effects on foliar elemental composition of Empetrum hermaphroditum and Vaccinium myrtillus in Sør-Varanger, northern Norway.

    Science.gov (United States)

    Uhlig, C; Junttila, O

    2001-01-01

    Uptake of Al, Cu, Fe, Mn, Ni, Ca, K, Mg, P, and S in Empetrum nigrum L. ssp. hermaphroditum Hagerup and Vaccinium myrtillus L. from Ni, Cu and SO2 contaminated sites in Sør-Varanger, northern Norway, were investigated. The primary objective was to study the effect of airborne heavy metal pollution on foliar element composition of these two dwarf shrubs. Ni distribution and availability in soils clearly indicate atmospheric deposition of Ni particulates in Sør-Varanger. Foliar Ni concentrations in E. hermaphroditum and V. myrtillus increased in relation to plant available Ni in corresponding soils. Leaves of E. hermaphroditum generally contained higher concentrations of Ni than leaves of V. myrtillus. Emissions influenced some features of leaf elemental composition of the two species in very different ways. In leaves of V. myrtillus, S increased in proportion to Ni and Cu, while levels of Mn decreased. In leaves of E. hermaphroditum, Fe increased in proportion to Ni and Cu, while levels of Ca decreased.

  15. Fast and simultaneously determination of light and heavy rare earth elements in monazite using combination of ultraviolet-visible spectrophotometry and multivariate analysis

    Science.gov (United States)

    Anggraeni, Anni; Arianto, Fernando; Mutalib, Abdul; Pratomo, Uji; Bahti, Husein H.

    2017-05-01

    Rare Earth Elements (REE) are elements that a lot of function for life, such as metallurgy, optical devices, and manufacture of electronic devices. Sources of REE is present in the mineral, in which each element has similar properties. Currently, to determining the content of REE is used instruments such as ICP-OES, ICP-MS, XRF, and HPLC. But in each instruments, there are still have some weaknesses. Therefore we need an alternative analytical method for the determination of rare earth metal content, one of them is by a combination of UV-Visible spectrophotometry and multivariate analysis, including Principal Component Analysis (PCA), Principal Component Regression (PCR), and Partial Least Square Regression (PLS). The purpose of this experiment is to determine the content of light and medium rare earth elements in the mineral monazite without chemical separation by using a combination of multivariate analysis and UV-Visible spectrophotometric methods. Training set created 22 variations of concentration and absorbance was measured using a UV-Vis spectrophotometer, then the data is processed by PCA, PCR, and PLSR. The results were compared and validated to obtain the mathematical equation with the smallest percent error. From this experiment, mathematical equation used PLS methods was better than PCR after validated, which has RMSE value for La, Ce, Pr, Nd, Gd, Sm, Eu, and Tb respectively 0.095; 0.573; 0.538; 0.440; 3.387; 1.240; 1.870; and 0.639.

  16. Production of neutron-rich nuclides in the heavy-element region via /sup 3/He-induced reactions

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Y.Y.; Zhou, M.L.

    1982-01-01

    We have measured the production cross sections for /sup 233/Th and /sup 231/Th from the bombardment of /sup 238/U with /sup 3/He ions at 46-, 53-, and 60-MeV at the Brookhaven 60-in. isochronous cyclotron. We have also attempted to observe the decay of /sup 233/Ac produced via /sup 238/U(/sup 3/He,/sup 8/B) or equivalent reactions using 61 MeV /sup 3/He ions by first separating thorium from actinium and then performing chemical purifications on the second thorium sample into which the actinium has decayed. In the four experiments we performed, three gave results consistent with the ..beta.. half-life of /sup 233/Ac somewhat longer than 120 s and the production cross section from this target-projectile combination in the order of 1 to 2 ..mu..b.

  17. Abundances of the heavy elements in the Magellanic Clouds. I. Metal abundances of F-type supergiants

    Energy Technology Data Exchange (ETDEWEB)

    Russell, S.C.; Bessell, M.S. (Mount Stromlo and Siding Spring Observatories, Canberra (Australia))

    1989-08-01

    Metal abundances of eight F-type supergiants in each of the Magellanic Clouds were determined using the results of high-resolution spectroscopy analysis of these stars, together with new Stromgren uvby and Cousins (1980) BVRI photometry. It was found that the mean Fe abundance (Fe/H) for the SMC is -0.65 + or - 0.2 dex, and the mean Fe abundance for the LMC is -0.30 + or - 0.2 dex. The abundances of stars in both the SMC and LMC appear relatively uniform, and the abundances of the elements relative to Fe are very similar in both Magellanic Clouds and in Canopus (the carbon-to-iron abundances are the same for all three). It was also found that Nd and Sm are overabundant in both clouds, supporting the trends found by Spite et al. (1988) for the three SMC stars they studied. 140 refs.

  18. Bioavailability of heavy metals, germanium and rare earth elements at Davidschacht dump-field in mine affected area of Freiberg (Saxony)

    Science.gov (United States)

    Midula, Pavol; Wiche, Oliver

    2016-04-01

    Bioavailability research presents an essential tool, in modern phytoremediation and phytomining technologies, allowing the estimation of plant available fractions of elements in soils. However, up to date, sufficient interdisciplinary knowledge on the biogeochemically impacted behavior of specific target elements, in particular Ge and REEs in mining affected soils and their uptake into strategically used plants is lacking. This presented work is focused on a correlation study between the concentrations of selected heavy metals, Ge and REEs in soils formed on the top of the dump-field of Davidschacht and the corresponding their concentrations in 12 vascular plant species. The mine-dump of Davidschacht, situated in the Freiberg (Saxony, Germany) municipality area was chosen as the study area, which has been considered to be a high contaminated enclave, due to the mining history of the region. In total 12 sampling sites with differing composition of plant species were selected. At each sampling site soil samples from a soil depth of 0 - 10 cm and samples of plant material (shoots) were taken. The soil samples were analysed for total concentration of elements, pH (H2O) and consequently analysed by 4-step sequential extraction (SE) to determine fractions of elements that are mobile (fraction 1), acid soluble (pH 5) (fraction 2), bound to organic and oxidizable matter (fraction 3) and bound to amorphic oxides (fraction 4). The plant material was decomposed by hydrofluoric acid in order to extract the elements. Concentrations of elements in soil extracts and digestion solutions were analysed by ICP-MS. For all species bioconcentration factor (BCF) was calculated of the total concentration of elements in order to investigate the bioaccumulation potential. Arsenic (As), cadmium (Cd) and lead (Pb) were chosen as the representative heavy metals. Within the REEs neodymium (Nd) and cerium (Ce) were selected as representatives for all REEs, since Nd and Ce correlated significant

  19. Investor's and procurement guide South Africa. Pt. 1. Heavy minerals, rare earth elements, antimony

    Energy Technology Data Exchange (ETDEWEB)

    Graupner, Torsten; Schwarz-Schampera, Ulrich [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Berlin (Germany); Hammond, Napoleon Q.; Opperman, Rehan; Long' a Tongu, Elisa; Kenan, Abdul O.; Nondula, Unathi; Tsanwani, Matamba [Council for Geoscience (CGS), Pretoria (South Africa). Dept. of Mineral Resources Development; Liedke, Maren; Marbler, Herwig [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Berlin (Germany). Deutsche Rohstoffagentur (DERA)

    2014-03-15

    This is the first part of the ''Investor's and Procurement Guide South Africa'', a handbook for investing and doing business in South Africa's mineral industry. It is anticipated that this publication will aid potential investors into considering South Africa as an investment destination, not only for raw materials, but also for related industries. This manual supplements the many publications available on the economic geology and mineral wealth in South Africa and has been designed to guide prospective and current investors, suppliers and mine equipment exporters through the process of doing business in Africa's biggest and dynamic economy. As well as detailing the mineral raw materials heavy minerals, rare-earth metals and antimony, the handbook provides a general introduction to South Africa and its infrastructure, the economical, political and judicial frame of the South African mining industry and an overview of the economic geology. South Africa has a long and complex geological history which dates back in excess of 3.6 billion years. The country has a vast mineral wealth, undoubtedly due to the fact that a significant proportion of the Archaean and younger rocks have been preserved. The mining of the enormous Witwatersrand gold deposits, commencing in 1886, has led to the establishment of South Africa's well-developed infrastructure and to the sustained growth of an industrial and service sector in the country. With the world's largest resources of PGMs, gold, chromite, vanadium and manganese and significant resources of iron, coal and numerous other minerals and metals, the minerals industry will continue to play a pivotal role in the growth of South Africa's economy in the foreseeable future. South Africa is one of the top destinations in Africa for foreign direct investments. South African headquartered companies have been major investors into foreign direct investments on the African continent in the past

  20. Determination of rare earth elements in natural water samples – A review of sample separation, preconcentration and direct methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, Andrew, E-mail: afisher@plymouth.ac.uk [School of Geography, Earth and Environmental Sciences, Plymouth University, Drake Circus, Plymouth, Devon, PL4 8AA (United Kingdom); Kara, Derya [Department of Chemistry, Art and Science Faculty, Balikesir University, 10100, Balikesir (Turkey)

    2016-09-07

    This review discusses and compares the methods given for the determination of rare earth elements (REE) in natural water samples, including sea, river, lake, tap, ground and waste waters as well as Antarctic ice. Since REE are at very low concentrations in natural waters, numerous different preconcentration methods have been proposed to enable their measurement. These include liquid liquid extraction, dispersive liquid-liquid micro-extraction and solidified floating drop micro-extraction. In addition to liquid-liquid extraction methods, solid phase extraction using commercial resins, resins made in-house, silica-based exchange materials and other solid media is also discussed. These and other techniques such as precipitation/co-precipitation and flotation are compared in terms of speed, preconcentration factors achieved, precision, accuracy and limits of detection (LOD). Some papers have discussed the direct determination of REE in these sample types. Some have used specialised sample introduction systems such as ultrasonic nebulization whereas others have used a standard sample introduction system coupled with inductively coupled plasma mass spectrometry (ICP-MS) detection. These direct methods have also been discussed and compared. - Highlights: • The determination of rare earth elements in waters is reviewed. • Assorted preconcentration techniques are discussed and evaluated. • Detection techniques include atomic spectrometry, potentiometry and spectrophotometry. • Special nebulisers and electrothermal vaporization approaches are reviewed.

  1. A Novel Synthesis Routine for Woodwardite and Its Affinity towards Light (La, Ce, Nd and Heavy (Gd and Y Rare Earth Elements

    Directory of Open Access Journals (Sweden)

    Sirio Consani

    2018-01-01

    Full Text Available A synthetic Cu-Al-SO4 layered double hydroxide (LDH, analogue to the mineral woodwardite [Cu1−xAlx(SO4x/2(OH2·nH2O], with x < 0.5 and n ≤ 3x/2, was synthesised by adding a solution of Cu and Al sulphates to a solution with NaOH. The pH values were kept constant at 8.0 and 10.0 by a continuous addition of NaOH. The material obtained had poor crystallinity, turbostratic structure, and consisted of nanoscopic crystallites. The analyses performed in order to characterise the obtained materials (X-ray diffraction (XRD, thermogravimetry (TG, and Fourier Transform Infra-Red (FTIR spectroscopy showed that the Cu-Al-SO4 LDH is very similar to woodwardite, although it has a smaller layer spacing, presumably due to a lesser water content than in natural samples. The synthesis was performed by adding light rare earth elements (LREEs (La, Ce, and Nd and heavy rare earth elements (HREEs (Gd and Y in order to test the affinity of the Cu-Al-SO4 LDH to the incorporation of REEs. The concentration of rare earth elements (REEs in the solid fraction was in the range of 3.5–8 wt %. The results showed a good affinity for HREE and Nd, especially for materials synthesised at pH 10.0, whereas the affinities for Ce and La were much lower or non-existent. The thermal decomposition of the REE-doped materials generates a mixture of Cu, Al, and REE oxides, making them interesting as precursors in REE oxide synthesis.

  2. Quantitative Evaluation of Heavy Metals and Trace Elements in the Urinary Bladder: Comparison Between Cancerous, Adjacent Non-cancerous and Normal Cadaveric Tissue.

    Science.gov (United States)

    Abdel-Gawad, Mahmoud; Elsobky, Emad; Shalaby, Mahmoud M; Abd-Elhameed, Mohamed; Abdel-Rahim, Mona; Ali-El-Dein, Bedeir

    2016-12-01

    The role of heavy metals and trace elements (HMTE) in the development of some cancers has been previously reported. Bladder carcinoma is a frequent malignancy of the urinary tract. The most common risk factors for bladder cancer are exposure to industrial carcinogens, cigarette smoking, gender, and possibly diet. The aim of this study was to evaluate HTME concentrations in the cancerous and adjacent non-cancerous tissues and compare them with those of normal cadaveric bladder. This prospective study included 102 paired samples of full-thickness cancer and adjacent non-cancerous bladder tissues of radical cystectomy (RC) specimens that were histologically proven as invasive bladder cancer (MIBC). We used 17 matched controls of non-malignant bladder tissue samples from cadavers. All samples were processed and evaluated for the concentration of 22 HMTE by using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Outcome analysis was made by the Mann-Whitney U, chi-square, Kruskal-Wallis, and Wilcoxon signed ranks tests. When compared with cadaveric control or cancerous, the adjacent non-cancerous tissue had higher levels of six elements (arsenic, lead, selenium, strontium, zinc, and aluminum), and when compared with the control alone, it had a higher concentration of calcium, cadmium, chromium, potassium, magnesium, and nickel. The cancerous tissue had a higher concentration of cadmium, lead, chromium, calcium, potassium, phosphorous, magnesium, nickel, selenium, strontium, and zinc than cadaveric control. Boron level was higher in cadaveric control than cancerous and adjacent non-cancerous tissue. Cadmium level was higher in cancerous tissue with node-positive than node-negative cases. The high concentrations of cadmium, lead, chromium, nickel, and zinc, in the cancerous together with arsenic in the adjacent non-cancerous tissues of RC specimens suggest a pathogenic role of these elements in BC. However, further work-up is needed to support this

  3. Water contamination with heavy metals and trace elements from Kilembe copper mine and tailing sites in Western Uganda; implications for domestic water quality.

    Science.gov (United States)

    Abraham, Mwesigye R; Susan, Tumwebaze B

    2017-02-01

    The mining and processing of copper in Kilembe, Western Uganda, from 1956 to 1982 left over 15 Mt of cupriferous and cobaltiferous pyrite dumped within a mountain river valley, in addition to mine water which is pumped to the land surface. This study was conducted to assess the sources and concentrations of heavy metals and trace elements in Kilembe mine catchment water. Multi-element analysis of trace elements from point sources and sinks was conducted which included mine tailings, mine water, mine leachate, Nyamwamba River water, public water sources and domestic water samples using ICP-MS. The study found that mean concentrations (mg kg-1) of Co (112), Cu (3320), Ni (131), As (8.6) in mine tailings were significantly higher than world average crust and were being eroded and discharged into water bodies within the catchment. Underground mine water and leachate contained higher mean concentrations (μg L-1) of Cu (9470), Co (3430) and Ni (590) compared with background concentrations (μg L-1) in un contaminated water of 1.9, 0.21 and 0.67 for Cu, Co and Ni respectively. Over 25% of household water samples exceeded UK drinking water thresholds for Al of 200 μg L-1, Co exceeded Winsconsin (USA drinking) water thresholds of 40 μg L-1 in 40% of samples while Fe in 42% of samples exceeded UK thresholds of 200 μg L-1. The study however found that besides mining activities, natural processes of geological weathering also contributed to Al, Fe, and Mn water contamination in a number of public water sources. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Uniform Distribution of Yttrium and Heavy Rare Earth Elements in Round Top Mountain Rhyolite Deposit , Sierra Blanca Texas, USA: Data, Significance, and Origin

    Science.gov (United States)

    Pingitore, N. E., Jr.; Clague, J. W.; Gorski, D.

    2014-12-01

    The Round Top Mountain peraluminous rhyolite, exposed at the surface in Sierra Blanca, Hudspeth County, west Texas, USA, is enriched in yttrium and heavy rare earth elements (YHREEs). Other potentially valuable elements in the deposit include Be, Li, U, Th, Sn, F, Nb, and Ta. Texas Rare Earth Resources Corp. proposes to extract the YHREEs from the host mineral variety yttrofluorite by inexpensive heap leaching with dilute sulfuric acid, which also releases some of the Be, Li, U, F, and Th from other soluble minor minerals. Data: Feldspars and quartz comprise 90-95% of the rhyolite, with pheonocrysts of up to 250 microns set in an aphanitic matrix that hosts the typically sub-micron target yttrofluorite. Reverse circulation cuttings from some 100 drill holes, two drill cores, and outcrop and trench observations suggest striking physical homogeneity through this billion-plus ton surface-exposed laccolith, about 1200 feet high and a mile in diameter (375 x 1600 m). Gray to pink, and other minor hues, color variation derives from magnetite—hematite redox reaction. Plots of Y, 13 REEs, U, Th, and Nb analyses from over 1500 samples collected from 64 drill holes (color codes in figure) exhibit remarkably little variation in the concentration of these elements with geographic position or depth within the laccolith. Importance: Uniform mineralization grades help insure against the mining production surprises often associated with vein deposits and heterogeneous open pit deposits. At Round Top, mine feedstock can be relatively constant over the life of the mine (multiple decades), so the mechanical mining process can be optimized early on and not need expensive alterations later. Likewise, the chemical and physical parameters of the heap leach can be perfected. The sensitive and expensive process of extraction of elements and element groups from the pregnant leach solution and purification also can be optimized. Origin: The remarkable homogeneity of the YHREE distribution

  5. Ecotoxicological characteristic of a soil polluted by radioactive elements and heavy metals before and after its bioremediation

    Science.gov (United States)

    Georgiev, P.; Groudev, S.; Spasova, I.; Nikolova, M.

    2012-04-01

    Cinnamon soils from southeastern Bulgaria are heavily polluted with radionuclides (uranium, radium) and toxic heavy metals (copper and lead) due to the winds transportation of fine particles from flotation dumps to the soil surface. As a result of this, the polluted soils are characterized by a slightly alkaline pH (7.82) and positive net neutralization potential (+136.8 kg CaCO3/t). A fresh sample of cinnamon soil was subjected to remediation under laboratory conditions in four lysimeters each containing 70 kg of soil. The preliminary study revealed that most of the pollutants were presented as carbonate, reducible and oxidisable mobility fractions, i.e. pollutants ions were specifically adsorbed by carbonate and ferric iron minerals or were capsulated in sulfides. The applied soil treatment was connected with leaching of the pollutants located mainly in the horizon A, their transportation through the soil profile as soluble forms, and their precipitation in the rich-in-clay subhorizon B3. The efficiency of leaching depended on the activity of the indigenous microflora and on the chemical processes connected with solubilization of pollutants and formation of stable complexes with some organic compounds, chloride and hydrocarbonate ions. These processes were considerably enhanced by adding hay to the horizon A and irrigating the soil with water solutions containing the above-mentioned ions and some nutrients. After 18 months of treatment, each of the soil profiles in the different lysimeters was divided into five sections reflecting the different soil layers. The soil in these sections was subjected to a detailed chemical analysis and the data obtained were compared with the relevant data obtained before the start of the experiment. The best leaching of pollutants from horizon A was measured in the variants where soil mulching was applied. For example, the best leaching of lead (54.5 %) was found in the variant combining this technique and irrigation with solutions

  6. Mechanical properties of UO2 thin films under heavy ion irradiation using nanoindentation and finite element modeling

    Science.gov (United States)

    Elbakhshwan, Mohamed S.; Miao, Yinbin; Stubbins, James F.; Heuser, Brent J.

    2016-10-01

    The mechanical response of UO2 to irradiation is becoming increasingly important due to the shift to higher burn-up rates in the next generation of nuclear reactors. In the current study, thin films of UO2 were deposited on YSZ substrates using reactive-gas magnetron sputtering. Nanoindentation was used to measure the mechanical properties of the as-grown and irradiated films. Finite element modeling was used to account for the substrate effect on the measurements. In order to study the effect of displacement cascades accompanying gas bubbles, 5000 Å UO2 films were irradiated with 600 keV Kr+ ions at 25 °C and 600 °C. These irradiation conditions were used to confine radiation damage effects and implanted gas within the film. Results showed an increase in the film hardness and yield strength with dose, while elastic modulus initially decreased with irradiation and then kept increasing with dose. The change in hardness and elastic modulus is attributed to the introduction of gas bubbles and displacement cascade damage. Irradiation at 600 °C resulted in a decrease in the hardness and elastic modulus after irradiation using 600 keV Kr+ at a dose of 1E14 ions/cm2. Both hardness and elastic modulus then increased with irradiation dose. This behavior is attributed to recrystallization during irradiation at 600 °C and the formation of nanocrystallite regions with diameter and density that increase with dose. The calculation of the critical resolved shear stress (CRSS) demonstrated that nanocrystals are the primary cause for film hardening based on the Orowan hardening mechanism.

  7. Mechanical properties of UO{sub 2} thin films under heavy ion irradiation using nanoindentation and finite element modeling

    Energy Technology Data Exchange (ETDEWEB)

    Elbakhshwan, Mohamed S., E-mail: elbakhs1@illinois.edu; Miao, Yinbin; Stubbins, James F.; Heuser, Brent J.

    2016-10-15

    The mechanical response of UO{sub 2} to irradiation is becoming increasingly important due to the shift to higher burn-up rates in the next generation of nuclear reactors. In the current study, thin films of UO{sub 2} were deposited on YSZ substrates using reactive-gas magnetron sputtering. Nanoindentation was used to measure the mechanical properties of the as-grown and irradiated films. Finite element modeling was used to account for the substrate effect on the measurements. In order to study the effect of displacement cascades accompanying gas bubbles, 5000 Å UO{sub 2} films were irradiated with 600 keV Kr{sup +} ions at 25 °C and 600 °C. These irradiation conditions were used to confine radiation damage effects and implanted gas within the film. Results showed an increase in the film hardness and yield strength with dose, while elastic modulus initially decreased with irradiation and then kept increasing with dose. The change in hardness and elastic modulus is attributed to the introduction of gas bubbles and displacement cascade damage. Irradiation at 600 °C resulted in a decrease in the hardness and elastic modulus after irradiation using 600 keV Kr{sup +} at a dose of 1E14 ions/cm{sup 2}. Both hardness and elastic modulus then increased with irradiation dose. This behavior is attributed to recrystallization during irradiation at 600 °C and the formation of nanocrystallite regions with diameter and density that increase with dose. The calculation of the critical resolved shear stress (CRSS) demonstrated that nanocrystals are the primary cause for film hardening based on the Orowan hardening mechanism.

  8. A new coprecipitation method without carrier element for separation and preconcentration of some metal ions at trace levels in water and food samples.

    Science.gov (United States)

    Gouda, Ayman A

    2016-01-01

    A new simple and sensitive preconcentration, separation and environmentally friendly method based on carrier element free coprecipitation (CEFC) was developed using 4-(2-hydroxybenzylideneamino)-1,2-dihydro-2,3-dimethyl-1-phenylpyrazol-5-one (APSAL) as a new organic co-precipitant to precipitate Cr(3+), Cu(2+), Fe(3+), Pb(2+) and Zn(2+) ions from water and food samples. The levels of the studied elements were detected by flame atomic absorption spectrometry (FAAS). The impact of several analytical parameters, such as pH, sample volume and coprecipitant amount as well as centrifugation rate and time was investigated to recover the examined metal ions. The influence of matrix ions was also tested, and no interferences were observed. The recovery values of the analyte ions were calculated and found to be in the range of 95-101%. The detection limits, corresponding to three times the standard deviation of the blank (N=10), were found to be in the range of 0.2-1.2 μg L(-1). The relative standard deviation (RSD) was calculated to evaluate the precision of the proposed method and was found to be ≤5.0%. The calculated preconcentration factor was 100. The proposed method was successfully applied to separate and preconcentrate trace amounts of ions in several water and food samples. To confirm the accuracy and validate the proposed method, certified reference materials were analyzed with satisfactory results. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Isotope separation

    Science.gov (United States)

    Bartlett, Rodney J.; Morrey, John 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.

  10. Element 74, the Wolfram Versus Tungsten Controversy

    Energy Technology Data Exchange (ETDEWEB)

    Holden,N.E.

    2008-08-11

    Two and a quarter centuries ago, a heavy mineral ore was found which was thought to contain a new chemical element called heavy stone (or tungsten in Swedish). A few years later, the metal was separated from its oxide and the new element (Z=74) was called wolfram. Over the years since that time, both the names wolfram and tungsten were attached to this element in various countries. Sixty years ago, IUPAC chose wolfram as the official name for the element. A few years later, under pressure from the press in the USA, the alternative name tungsten was also allowed by IUPAC. Now the original, official name 'wolfram' has been deleted by IUPAC as one of the two alternate names for the element. The history of this controversy is described here.

  11. Study of the behaviour of some heavy elements in solvents containing hydrogen fluoride; Etude du comportement de quelques elements lourds dans des solvants a base d'acide fluorhydrique

    Energy Technology Data Exchange (ETDEWEB)

    Tarnero, M. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-01-01

    The anhydrous liquid mixtures: dinitrogen tetroxide-hydrogen fluoride and antimony pentafluoride-hydrogen fluoride were studied as solvents for heavy elements interesting nuclear energy: uranium, thorium, zirconium and for some of their compounds. For N{sub 2}O{sub 4}-HF mixtures, electric conductivity measurements and liquid phase infrared spectra were also obtained. Uranium and zirconium tetrafluoride are much more soluble in N{sub 2}O{sub 4}-HF mixtures than in pure hydrogen fluoride. Uranium dissolved in these mixtures is pentavalent. In SbF{sub 5}-HF mixtures, uranium dissolves with hydrogen evolution and becomes trivalent. The solid compound resulting from the dissolution is a fluoro-antimonate: U(SbF{sub 6}){sub 3}. (author) [French] On a etudie les melanges liquides anhydres: peroxyde d'azote-acide fluorhydrique et pentafluorure d'antimoine-acide fluorhydrique comme solvants d'elements lourds interessant l'energie nucleaire: uranium, thorium, zirconium et de quelques uns de leurs composes. Pour les melanges N{sub 2}O{sub 4}-HF on a egalement effectue des mesures de conductivite electrique, ainsi que des spectres d'absorption infrarouge en phase liquide. Le tetrafluorure d'uranium et le tetrafluorure de zirconium sont beaucoup plus solubles dans les melanges N{sub 2}O{sub 4}-HF que dans l'acide fluorhydrique. L'uranium dissous dans ces melanges est a l'etat pentavalent. Dans les melanges SbF{sub 5}-HF l'uranium se dissout avec degagement d'hydrogene et passe a l'etat trivalent. Le compose solide resultant de la dissolution est un fluoantimoniate: U(SbF{sub 6}){sub 3}. (auteur)

  12. Micro-distribution of heavy rare earth elements in Round Top Mountain rhyolite deposit (Hudspeth County, Texas, USA) by EPMA mapping

    Science.gov (United States)

    Pingitore, N. E., Jr.; Piranian, M.; Amaya, M. A.; Negron, L. M.; Gorski, D.

    2015-12-01

    Round Top Mountain, west Texas, USA, is composed almost entirely of peraluminous rhyolite, with pervasive low-grade enrichment in yttrium and heavy rare earth elements (Y+HREEs). The exposed rhyolite laccolith also contains Li, Be, U, Th, Nb, Ta, Ga, Rb, Cs, Sn, and F. The valuable Y+HREEs are hosted in yttrofluorite, which is soluble in dilute sulfuric acid. Texas Rare Earth Resources, Inc. proposes to surface mine, crush, and heap leach the massive, 109ton deposit. The distribution of Y+HREEs, and that of other trace elements, is remarkably homogeneous at outcrop drill hole scale (Pingitore et al., FM14-V23D-4827: Uniform Distribution of Yttrium…). Here we document that Y+HREE mineralization appears pervasive through the rhyolite at a sub-millimeter scale. We examined 15 thin sections of rhyolite fragments randomly selected from a composite sample produced by mixing several hundred kg of aliquot material recovered from >100 reverse circulation drill holes scattered across much of the mountain. A total of 16 elements (Y, Dy, Yb, F, U, Th, Nb, Sn, Zr, Rb, Ca, Na, K, Fe, Al, Si) plus back scattered electron image were mapped in WDS mode by stage raster across a 2 x 2 mm field at 516 x 516 pixel resolution on a Cameca SX-100 class EPMA. Typical maps revealed 5-10 grains that contained Y + Dy + Yb; most also contained F and Ca, indicating yttrofluorite mineralogy. Most grains were under 10 μm in 2-D size. We view this 5-10 grain figure of merit as a minimum number of target grains since we employed a conservative approach to their identification. This finding suggests that a 1 mm cube of the rhyolite contains 250-500 target grains (assuming that the EPMA sampled to a depth of 5 μm and that sampled grains did not extend below that depth in size). Viewed from a mining processing standpoint, each particle for the anticipated heap leach, with a nominal crush size of ½ to 1 inch (13-26 mm), would contain on the order of 250,000 to 500,000 target microscopic mineral

  13. Separation Process of Fine Coals by Ultrasonic Vibration Gas-Solid Fluidized Bed

    Directory of Open Access Journals (Sweden)

    Shuai Wang

    2017-01-01

    Full Text Available Ultrasonic vibration gas-solid fluidized bed was proposed and introduced to separate fine coals (0.5–0.125 mm fraction. Several technological methods such as XRF, XRD, XPS, and EPMA were used to study the composition of heavy products to evaluate the separation effect. Results show that the ultrasonic vibration force field strengthens the particle separation process based on density when the vibration frequency is 35 kHz and the fluidization number is 1.8. The ash difference between the light and heavy products and the recovery of combustible material obtain the maximum values of 47.30% and 89.59%, respectively. The sulfur content of the heavy product reaches the maximum value of 6.78%. Chemical state analysis of sulfur shows that organic sulfur (-C-S-, sulfate-sulfur (-SO4, and pyrite-sulfur (-S2 are confirmed in the original coal and heavy product. Organic sulfur (-C-S- is mainly concentrated in the light product, and pyrite-sulfur (-S2 is significantly enriched in the heavy product. The element composition, phase composition, backscatter imagery, and surface distribution of elements for heavy product show concentration of high-density minerals including pyrite, quartz, and kaolinite. Some harmful elements such as F, Pb, and As are also concentrated in the heavy product.

  14. Interlaminar shear stresses and laminae separation in a disc. Finite element analysis of the L3-L4 motion segment subjected to axial compressive loads.

    Science.gov (United States)

    Goel, V K; Monroe, B T; Gilbertson, L G; Brinckmann, P

    1995-03-15

    This study analyzed interlaminar shear stresses across the laminae of a ligamentous L3-L4 motion segment. A three-dimensional finite element model of the motion segment was developed and its response in axial compression mode was predicted. The contributions of "mechanical" factors in producing laminae separation in a disc are not well understood, especially when the nucleus is still gel-like in appearance (stage 1 of disc degeneration). All types of stresses are likely to contribute to laminae separation. The authors believe it is partially due to the interlaminar shear stresses at the laminae interfaces in specific regions of an intact disc because the disc is a composite structure. The effects of anular tears on the interlaminar shear stresses were also investigated. These tears can be circumferential or radial in nature, and commonly occur in the aged, degenerated disc. A large number of biomechanical studies dealing with the role of the disc vis-a-vis other spinal components have been reported in the literature. The role of mechanical factors, however, in producing laminae separation, especially when the nucleus is still gel-like in appearance (stage 1 of disc degeneration), is not entirely clear. A three-dimensional nonlinear finite element model of an intact L3-L4 lumbar motion segment, based on the use of a special type of element for the disc anulus, was created to investigate the interlaminar shear stresses in the anulus. The effects of radial "out-in," radial "in-out," and "circumferential" injuries were analyzed. Injury was modeled as element removal in the posterolateral portion of the disc. Models subjected to axial compressive loads, ranging from 200 N to 2000 N, were analyzed. In addition to the interlaminar shear stresses, disc bulge, and displacements including coupled motions were predicted. The theoretical disc bulge predictions for the radial in-out injury case were in agreement with the disc bulge data obtained experimentally. Displacements

  15. Carrier element-free coprecipitation (CEFC) method for separation and pre-concentration of some metal ions in natural water and soil samples.

    Science.gov (United States)

    Saracoglu, Sibel; Soylak, Mustafa

    2010-05-01

    A simple, rapid and sensitive separation/pre-concentration procedure for Cd(II), Cr(III), Co(II), Cu(II), Fe(III), Pb(II) and Mn(II) ions in environmental samples has been established. The present procedure is based on a combination of carrier element-free coprecipitation (CEFC) and flame atomic absorption spectrometric (FAAS) determinations of understudy trace metal ions. A cationic surfactant (N-cetyl N,N,N trimethyl ammonium bromide (CTAB)) as coprecipitant was used without adding any carrier element for coprecipitation of understudy ions. The optimum conditions for the coprecipitation process were investigated on several commonly tested experimental parameters, such as pH of the solution, amount of coprecipitant. The pre-concentration factor was found to be 10. The detection limits corresponding to three times the standard deviation of the blank (N=20) for Cd(II), Cr(III), Co(II), Cu(II), Fe(III), Pb(II) and Mn(II) ions were found as 0.61, 16.8, 12.7, 1.36, 2.08, 4.30 and 0.22 microg L(-1), respectively. The present procedure was successfully applied for separation and pre-concentration of investigated ions in several liquid environmental samples. In order to support the accuracy of the method, the certified reference materials (BCR 141 R calcareous loam soil and CRM025-050 soil) were analyzed. The experimental results are in good agreement with the certified values. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  16. New reversed phase-high performance liquid chromatographic method for selective separation of yttrium from all rare earth elements employing nitrilotriacetate complexes in anion exchange mode.

    Science.gov (United States)

    Dybczyński, Rajmund S; Kulisa, Krzysztof; Pyszynska, Marta; Bojanowska-Czajka, Anna

    2015-03-20

    Separation of Y from other rare earth elements (REE) is difficult because of similarity of its ionic radius to ionic radii of Tb, Dy and Ho. In the new RP-HPLC system with C18 column, tetra-n-butyl ammonium hydroxide (TBAOH) as an ion interaction reagent (IIR), nitrilotriacetic acid (NTA) as a complexing agent at pH=2.8-3.5, and post column derivatization with Arsenazo III, yttrium is eluted in the region of light REE, between Nd and Sm and is base line separated from Nd and Sm and even from promethium. Simple model employing literature data on complex formation of REE with NTA and based on anion exchange mechanism was developed to foresee the order of elution of individual REE. The model correctly predicted that lanthanides up to Tb will be eluted in the order of increasing Atomic Number (At.No.) but all heavier REE will show smaller retention factors than Tb. Concurrent UV/VIS detection at 658nm and the use of radioactive tracers together with γ-ray spectrometric measurements made possible to establish an unique elution order of elution of REE: La, Ce, Pr, Nd, Pm, Y, Sm, Er, Ho, Tm, Yb, Eu, Lu, Dy+Gd, Tb, Sc. The real place of Y however, in this elution series differs from that predicted by the model (Y between Sm and Eu). The method described in this work enables selective separation of Y from La, Ce, Pr, Nd, Pm, Sm and all heavier REE treated as a group. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Separation tests of heavy metals in samples of industrial wastes through flotation; Pruebas de separacion de metales pesados en muestras de residuos industriales mediante flotacion

    Energy Technology Data Exchange (ETDEWEB)

    Abrego L, J

    1995-12-15

    Samples of residual muds, taken at the exit of the filter-press of the water treatment plant of a galvanoplastics industry in Lerma, Estado de Mexico, its were prepared for its qualitative and quantitative analysis. Likewise, the residual waters of the cistern located at the end of the electrodeposition process, was subjected to qualitative chemical analysis for the neutron activation technique and to quantitative analysis by atomic absorption spectrometry. The samples were treated by a flotation process by means of the one which it was studied the heavy metals removal. The results show that the AP-845 collector is the one that better it fulfilled the objectives since, it solves the problem, unless by the copper that although their concentration in the residual waters drop a lot, it was not inside the standard. (Author)

  18. Role of CrRLK1L Cell Wall Sensors HERCULES1 and 2, THESEUS1, and FERONIA in Growth Adaptation Triggered by Heavy Metals and Trace Elements

    Directory of Open Access Journals (Sweden)

    Julia Richter

    2017-09-01

    Full Text Available Cell walls are not only a protective barrier surrounding protoplasts but serve as signaling platform between the extracellular environment and the intracellular physiology. Ions of heavy metals and trace elements, summarized to metal ions, bind to cell wall components, trigger their modification and provoke growth responses. To examine if metal ions trigger cell wall sensing receptor like kinases (RLKs of the Catharanthus roseus RLK1-like (CrRLK1L family we employed a molecular genetic approach. Quantitative transcription analyses show that HERCULES1 (HERK1, THESEUS1 (THE1, and FERONIA (FER were differently regulated by cadmium (Cd, nickel (Ni, and lead (Pb. Growth responses were quantified for roots and etiolated hypocotyls of related mutants and overexpressors on Cd, copper (Cu, Ni, Pb, and zinc (Zn and revealed a complex pattern of gene specific, overlapping and antagonistic responses. Root growth was often inversely affected to hypocotyl elongation. For example, both HERK genes seem to negatively regulate hypocotyl elongation upon Cd, Ni, Zn, and Pb while they support root growth on Cd, Cu, and Ni. The different THE1 alleles exhibited a similar effect between roots and hypocotyls on Ni, where the loss-of-function mutant was more tolerant while the gain of function mutants were hypersensitive indicating that THE1 is mediating Ni specific inhibition of hypocotyl elongation in the dark. In contrast hypocotyl elongation of the knock-out mutant, fer-4, was hypersensitive to Ni but exhibited a higher tolerance to Cd, Cu, Pb, and Zn. These data indicate an antagonistic action between THE1 and FER in relation to hypocotyl elongation upon excess of Ni. FERs function as receptor for rapid alkalinization factors (RALFs was tested with the indicator bromocresol purple. While fer-4 roots strongly acidified control and metal ion containing media, the etiolated hypocotyls alkalized the media which is consistent with the already shorter hypocotyl of fer-4

  19. Hexavalent chromium recovery by liquid–liquid extraction with 2-octylaminopyridine from acidic chloride media and its sequential separation from other heavy toxic metal ions

    Directory of Open Access Journals (Sweden)

    C.P. Mane

    2016-11-01

    Full Text Available A systematic study of extraction of chromium(VI with 2-octylaminopyridine (2-OAP in xylene at room temperature has been conducted. Quantitative extraction of chromium(VI was observed in the 0.4–0.8 M concentration range of hydrochloric acid. From the extracted complex species in the organic phase, chromium(VI was back extracted with 7 N ammonia (3 × 10 mL, and was determined by spectrophotometric method. Various parameters such as 2-OAP concentration, equilibrium period, effect of various diluents, aqueous: organic volume ratio, acidity and diverse ions were studied. The extraction reaction proceeds with ion-pair formation and the stoichiometry of extracted species was found to be [(2OAPH+ CrO3Cl−](org. The separation and determination of chromium(VI from associated and toxic metals in binary, ternary and multicomponent mixture were carried out. The method permits the sequential separation of chromium(VI from other toxic metals and has been used to separate and determine chromium(VI from alloys, and effluent water samples from tannery industries.

  20. Chromatographic hydrogen isotope separation

    Science.gov (United States)

    Aldridge, Frederick T.

    1981-01-01

    Intermetallic compounds with the CaCu.sub.5 type of crystal structure, particularly LaNiCo.sub.4 and CaNi.sub.5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation colum. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale mutli-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.

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

    Science.gov (United States)

    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

    2013-03-15

    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. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. On the concentration and separation of the trace-elements Fe, Cu, Zn, Mn, Pb, Mo and Co : III. Paper chromatography

    NARCIS (Netherlands)

    Erkelens, P.C. van

    Paper chromatographic separations are described by which the minor constituents of biological ashes are separated either into: (Pb) --- Mn --- Co --- (Pb) --- Cu --- Fe, Mo, Zn; or into: Cu, Mn, Co --- Pb --- Fe --- Mo --- Zn.

  3. Off-line separation and determination of rare earth elements associated with chloroplast pigments of hyperaccumulator Dicranopteris dichotomaby normal-phase liquid chromatography and ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Z.G.; Li, H.X.; Hu, F. [Nanjing Agricultural University, College of Resources and Environmental Sciences, Nanjing 210095 (China); Hong, F.S. [Suzhou University, Department of Biology, College of Life Sciences, Suzhou 215006 (China); Yin, M. [Chinese Academy of Geological Sciences, National Research Center for Geoanalysis, Beijing 100037 (China); Zhao, G.W. [University of Science and Technology of China, Department of Chemistry, Hefei 230026 (China); Wong, J.W.C. [Hong Kong Baptist University, Department of Biology, Kowloon Tong, Hong Kong SAR (China)

    2004-10-01

    An off-line normal-phase liquid chromatography-ICP-MS method has been used for separation and determination of the rare earth elements (REE) associated with chloroplast pigments of Dicranopteris dichotoma. The stability of REE-bound pigments was tested, and almost no destruction of REE-bound pigments occurred during the so-called normal-phase liquid chromatography. The accumulated free REE ions on the microcrystalline cellulose column were cleaned by elution with 5 mmol L{sup -1} 2-ethylhexyl hydrogen 2-ethylhexylphosphonate (P507), to avoid exchange of these free ions with metals from the pigments. When these precautions were taken, the method was applied to the study of REE-bound pigments in D. dichotoma. ICP-MS results showed REE were present in chlorophylls and lutein, although REE concentrations in carotene and pheophytin were both below procedural blank levels. By careful analysis of the eluate fractions containing chlorophyll a it was found that REE-bound chlorophyll a in D. dichotoma was slightly enriched in the fractions with relatively short retention time. Results indicated that the retention time of REE-bound chlorophyll a might be slightly less than that of magnesium chlorophyll a, and REE-bound chlorophylls might be of relatively low polarity in comparison with magnesium bound chlorophylls. This phenomenon could be explained by the special double-decker sandwich-structure of REE-bound chlorophylls, as was reported by us and other authors. On the basis of these results we preferred to consider that REE can replace magnesium in chlorophyll a of D. dichotoma, and that the role of REE-bound chlorophylls in photosynthesis cannot be neglected. These data might be useful for understanding of both the properties of REE-bound pigments and the effect of REE on plant photosynthesis. (orig.)

  4. Off-line separation and determination of rare earth elements associated with chloroplast pigments of hyperaccumulator Dicranopteris dichotoma by normal-phase liquid chromatography and ICP-MS.

    Science.gov (United States)

    Wei, Z G; Hong, F S; Yin, M; Li, H X; Hu, F; Zhao, G W; Wong, J W C

    2004-10-01

    An off-line normal-phase liquid chromatography-ICP-MS method has been used for separation and determination of the rare earth elements (REE) associated with chloroplast pigments of Dicranopteris dichotoma. The stability of REE-bound pigments was tested, and almost no destruction of REE-bound pigments occurred during the so-called normal-phase liquid chromatography. The accumulated free REE ions on the microcrystalline cellulose column were cleaned by elution with 5 mmol L(-1) 2-ethylhexyl hydrogen 2-ethylhexylphosphonate (P507), to avoid exchange of these free ions with metals from the pigments. When these precautions were taken, the method was applied to the study of REE-bound pigments in D. dichotoma. ICP-MS results showed REE were present in chlorophylls and lutein, although REE concentrations in carotene and pheophytin were both below procedural blank levels. By careful analysis of the eluate fractions containing chlorophyll a it was found that REE-bound chlorophyll a in D. dichotoma was slightly enriched in the fractions with relatively short retention time. Results indicated that the retention time of REE-bound chlorophyll a might be slightly less than that of magnesium chlorophyll a, and REE-bound chlorophylls might be of relatively low polarity in comparison with magnesium bound chlorophylls. This phenomenon could be explained by the special double-decker sandwich-structure of REE-bound chlorophylls, as was reported by us and other authors. On the basis of these results we preferred to consider that REE can replace magnesium in chlorophyll a of D. dichotoma, and that the role of REE-bound chlorophylls in photosynthesis cannot be neglected. These data might be useful for understanding of both the properties of REE-bound pigments and the effect of REE on plant photosynthesis.

  5. Genes and quantitative trait loci (QTL) controlling trace element concentrations in perennial grasses grown on phytotoxic soil contaminated with heavy metals

    Science.gov (United States)

    Perennial grasses cover diverse soils throughout the world, including sites contaminated with heavy metals, producing forages that must be safe for livestock and wildlife. Chromosome regions known as quantitative trait loci (QTLs) controlling forage mineral concentrations were mapped in a populatio...

  6. Separate Colors, Separate Minds.

    Science.gov (United States)

    Meyers, Michael; Nidiry, John P.

    2002-01-01

    Explains that racial separation causes cultural separation, and the way to improve race relations is to continue to move toward integration. Discusses the need to debunk race, examining racial issues in education. Highlights the importance of actively supporting integration and opposing separatism, explaining that for there to be social progress,…

  7. Investigation of special resins for the extraction-chromatogaphic separation of Np and Pu from the process stream of a reprocessing plant for HTR fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, G.

    1977-03-15

    The effectiveness of several special resins for extraction chromatographic separation of plutonium and neptunium from the process streams of a reprocessing plant was investigated. These special resins consisted of polystyrol and were loaded with Tri-n-octylamine (TOA) during the polymerization process. A commercial structural body of polytrifluormonochlorethylene (Voltalef), subsequently wetted with TOA, served as reference material. Despite its good separation characteristics, this separation body has considerable disadvantages. The individual particles of separation body are only approximately spherical, the homogeneity of the separation bed is consequently only moderate. This size (85% less than 0.062 mm) and the shape of the separation body particles cause high pressure loss in the solution which streams through. Filling the column with the Voltalef separation body is very complicated and often not reproducible. A relatively high elution rate of the stationary phase and low radiation resistance are other disadvantages of this separation body. Because of the unfavorable characteristics of the Voltalef separation body, the above mentioned polystyrol resins have been developed by the Bayer firm. The individual separation body particles of these resins have ideal spherical shape. The diameter of the spheres is 0.4 to 0.6 mm, causing only slight pressure losses in a chromatographic column. A homogeneous and compact column fill is much simpler to achieve with these resins than with Voltalef. Radiation resistance and elution rate of the polystyrol resins correspond to the expectations which must be met during hot operation. The separation characteristics of the investigated polystyrol resins are not optimum, however. The relatively large separation body particles considerably delay the establishment of equilibrium, for two reasons. The rate-determining step during loading is diffusion through an aqueous film, which surrounds the separation body particles.

  8. Analyses élémentaires (carbone,hydrogène,oxygène,azote,soufre des fractions lourdes du pétrole. Elemental Analysis (Carbon,Hydrogen,Oxygen,Nitrogen,Sulfur of Heavy Oil Fractions Bibliographic Study

    Directory of Open Access Journals (Sweden)

    Barbelet M.

    2006-11-01

    Full Text Available La détermination des éléments carbone, hydrogène, oxygène, azote, soufre est essentielle pour la connaissance des fractions lourdes du pétrole. Cette étude bibliographique présente les principales méthodes d'analyse élémentaire utilisées dans ce domaine. On décrit les méthodes de minéralisation, de détection, et l'évolution suivie depuis plusieurs années dans l'automatisation des dosages. Determining, carbon, hydrogen, oxygen, nitrogen and sulfer elements is essential for understanding heavy oil fractions. This bibliographic study describes the leading elemental analysis methods used in this field. Mineralization and detection methods are described, and the development of titra-tion automation in recent years is reviewed.

  9. Assessment of the Risk of Non-Cancerous Diseases under the Exposure of Heavy Element in Urban Areas and Troubleshooting Pollutant Sources (The Case of Zanjan

    Directory of Open Access Journals (Sweden)

    Faramarz Moattar

    2017-06-01

    Full Text Available Background: Heavy metals are the main air pollutants in cities. Therefore, assessment of the risk of exposure to these metals through inhalation, ingestion, and dermal contact on inhabitants of contaminated areas of the world is of great importance. Methods: A weekly sampling of air particles smaller than 10 microns was performed in a residential area of Zanjan for two years. Risk assessment in the face of heavy metals from inhalation, ingestion, and dermal contact for were measured for two children and adults. After fingerprinting high-risk metals, the air pollutants of the region were analyzed according to the PMF5 model. Results: The results showed that children at risk assessment (1.40 × 1000 at the highest concentration of manganese. The PMF5 model results of fingerprinting 15 heavy metals showed that predominant pollutants in the region, included lead and zinc industries with 42.3%, suspended soil with 26.4%, industrial activities with 23.5%, and combustion and fuel with 7.8% of contamination. It was also found that 55.5 percent of manganese emission was associated with lead and zinc industries and 22.4 percent were related to suspended soil. Conclusion: Risk assessment showed that children were exposed to non-cancerous diseases due to inhalation of manganese particles.

  10. Heavy Chain Diseases

    Science.gov (United States)

    ... heavy chain produced: Alpha Gamma Mu Alpha Heavy Chain Disease Alpha heavy chain disease (IgA heavy chain ... disease or lead to a remission. Gamma Heavy Chain Disease Gamma heavy chain disease (IgG heavy chain ...

  11. Electrodialytic Removal of Heavy Metals from Different Solid Waste Products

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Christensen, Iben Vernegren; Pedersen, Anne Juul

    2003-01-01

    A variety of heavy metal polluted waste products must be handled today. Electrochemical methods have been developed for remediation of polluted soil. One of the methods is the electrodialytic remediation method that is based on electromigration of heavy metal ions and ionic species within the soil...... matrix, and a separation of the soil and the process solutions, where the heavy metals are concentrated, with ion exchange membranes. For remediation of some soils, such as calcareous soils, it is necessary to add an enhancement solution. It was shown in a laboratory experiment that ammonium citrate...... could be used when removing Cu and Cr from a soil with 25% carbonates. The final concentrations of the elements were below the target values after the remediation. A question of whether the electrodialytic remediation method can be used for other waste products arose. Preliminary experiments showed...

  12. Study On The Separation And Extraction Of Rare-Earth Elements From The Phosphor Recovered From End Of Life Fluorescent Lamps

    Directory of Open Access Journals (Sweden)

    Shin D.-W.

    2015-06-01

    Full Text Available In this study, recovered phosphor from end of life three-wavelength fluorescent lamp was selected for reuse rare earth elements in the phosphor. The effect of a type of acid, concentration, and time was investigated as solubility of rare earth elements. In addition, precipitate heat-treated was investigated as possibility of reusable phosphor. The results showed that the amount of the rare earth elements was different values depending on the type of acid, and it was investigated with concentration of acid and reaction time. After precipitation reaction, the precipitate was sintered in electric furnace in order to reuse rare earth elements as phosphor. It was confirmed that yttrium, europium, oxygen, and carbon through X-ray diffraction and inductively coupled plasma analysis. Following the results, it can assume that rare earth oxide reuse the phosphor as three-wavelength fluorescent lamp.

  13. 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).

  14. Elemental composition study of heavy metal (Ni, Cu, Zn) in riverbank soil by electrokinetic-assisted phytoremediation using XRF and SEM/EDX

    Energy Technology Data Exchange (ETDEWEB)

    Jamari, Suhailly [Faculty of Science, Technology and Human Development, Universiti Tun Hussein Onn Malaysia (UTHM) (Malaysia); Embong, Zaidi [Faculty of Science, Technology and Human Development, Universiti Tun Hussein Onn Malaysia (UTHM) and Research Center for Soft Soils (RECESS), Office of Research, Innovation, Commercialization and Consultancy Management - ORRIC, Universiti Tun Hussein (Malaysia); Bakar, Ismail [Research Center for Soft Soils (RECESS), Office of Research, Innovation, Commercialization and Consultancy Management (ORRIC), Universiti Tun Hussein Onn Malaysia -UTHM, 86400 Batu Pahat, Johor (Malaysia)

    2014-02-12

    Electrokinetic (EK)-assisted phytoremediation is one of the methods that have a big potential in enhancing the ability of plant uptake in soils remediation process. This research was conducted to investigate the difference in elemental composition concentration of riverbank soil and the change of pH between pre- and post-phytoremediation under the following condition: 1) control or as-receive sample; 2) Dieffenbachia spp plant with EK system (a pair of EK electrodes connected to a direct current (DC) power supply). After the electrodes were connected to a magnitude of 6V/cm{sup −1} electric field for 4 hours/day, the soil and plant samples were analyzed using and X-ray Fluorescence Spectrometer (XRF) and Scanning Electron Microscope / Energy Dispersive X-ray Spectroscopy (SEM/EDX). The SEM/EDX analysis showed that concentration of elemental composition (Ni, Cu and Zn) in post-phytoremediation plant powder samples had increase while elemental concentrations in the post-phytoremediation soil samples were decreased. XRF analysis presented a variation in soil elemental composition concentration from anode to cathode where the concentration near anode region increased while decreased near the cathode region. A significant changes in soil pH were obtained where the soil pH increase in cathode region while decrease in anode region. The results reveal that the assistance of EK in phytoremediation process has increase the efficiency of plant uptake.

  15. Gradient of heavy elements in the sea bed of the Gulf of Tehuantepec; Gradiente de elementos pesados en el lecho marino del Golfo de Tehuantepec

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez T, J.J.; Lopez M, J.; Aspiazu F, J.A.; Villasenor S, P.; Ordonez, E.; Gutierrez, A. [ININ, Carretera Mexico-Toluca S/N, La Marquesa, Ocoyoacac, Mex. C.P. 52750 (Mexico); Ruiz F, A.C. [U. Academica Mazatlan UNAM, Inst. de Ciencias del Mar y Limnologia (Mexico)].e-mail: jrt@nuclear.inin.mx

    2006-07-01

    Using the PIXE technique the concentrations of some elements was analyzed weighed in a sedimentary nucleus gathered in the Gulf of Tehuantepec. The certain profiles of concentrations are presented and the utility of the PIXE technique is demonstrated for the study of environmental processes. (Author)

  16. On the concentration and separation of the trace-elements Fe, Cu, Zn, Mn, Pb, Mo and Co : II. Solvent extraction

    NARCIS (Netherlands)

    Erkelens, P.C. van

    Extractions with acetylacetone and diethyldithiocarbamate are described. Through the successive application of these reagents the constituents of biological ashes are concentrated and separated into the groups: (I) MoO4−2, (2) Fe+3, Cu+2, (3) Mn+2, (4) Zn+2, (5) Pb+2, (6) Co+3 and (7) Na+, K+, Ca+2,

  17. An experimental paradigm opening the world of superheavy elements

    Science.gov (United States)

    Armbruster, P.; Münzenberg, Gottfried

    2012-07-01

    The history of the discovery of the six elements Z = 107 - 112, bohrium, hassium, meitnerium, darmstadtium, roentgenium, and copernicium goes back to the early 1960s. An experimental method to separate and identify rare nuclear reaction products, the recoil separation, was developed and optimised for beams of fission products at European research reactors. Chemical elements beyond the then first transactinides (Z = 104), which owe their stability to the internal structure of atomic nuclei, were predicted theoretically. A big brother of the shell-stabilised nucleus 208Pb, a spherical magic nucleus at Z = 114-126 and N = 184, might reach lifetimes long enough to be detected. In the seventies, hunting superheavy elements (SHE) was on the agenda of nuclear chemistry. Could the Periodic Table of Elements be extended to Z = 120, and is the order of electrons in the atom still following the laws established for lighter elements? In Germany, the heavy ion accelerator (UNILAC) was built by Christoph Schmelzer and his team at GSI, Darmstadt. SHE and UNILAC met the recoil separators in 1968, and SHIP (Separator for Heavy Ion reaction Products) was ready together with the first UNILAC-beams in 1976. Recoil separation is orders of magnitude more sensitive, selective, and faster than earlier methods used to synthesise elements up to seaborgium, Z = 106. The experimental paradigm we introduced opened the world of SHEs. At SHIP we discovered and investigated the elements Z = 107-112 in the years 1980-2000. Our laboratory was the world champion during this time. Today our experimental method is used worldwide in the search for SHEs, but the leadership went to the Russian laboratory JINR in Dubna, which extended the Periodic Table by 6 more elements to Z = 118, the candidate for the next rare gas.

  18. High-precision analysis on annual variations of heavy metals, lead isotopes and rare earth elements in mangrove tree rings by inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yu Kefu [South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xin-Gang Road, Guangzhou 510301 (China) and Radiogenic Isotope Laboratory, Centre for Microscopy and Microanalysis (CMM), University of Queensland, Qld 4072 (Australia)]. E-mail: kefuyu@scsio.ac.cn; Kamber, Balz S. [Radiogenic Isotope Laboratory, Centre for Microscopy and Microanalysis (CMM), University of Queensland, Qld 4072 (Australia); Department of Earth Sciences, Laurentian University, Sudbury, ONP3E2C6 (Canada); Lawrence, Michael G. [Radiogenic Isotope Laboratory, Centre for Microscopy and Microanalysis (CMM), University of Queensland, Qld 4072 (Australia); Greig, Alan [Radiogenic Isotope Laboratory, Centre for Microscopy and Microanalysis (CMM), University of Queensland, Qld 4072 (Australia); School of Earth Sciences, University of Melbourne, Vic. 3010 (Australia); Zhao Jianxin [Radiogenic Isotope Laboratory, Centre for Microscopy and Microanalysis (CMM), University of Queensland, Qld 4072 (Australia)

    2007-02-15

    Annual variations from 1982 to 1999 of a wide range of trace elements and reconnaissance Pb isotopes ({sup 207}Pb/{sup 206}Pb and {sup 208}Pb/{sup 206}Pb) were analyzed by solution ICP-MS on digested ash from mangrove Rhizophora apiculata, obtained from Leizhou Peninsula, along northern coast of South China Sea. The concentrations of the majority of elements show a weak declining trend with growth from 1982 to 1999, punctuated by several high concentration spikes. The declining trends are positively correlated with ring width and negatively correlated with inferred water-use efficiency, suggesting a physiological control over metal-uptake in this species. The episodic metal concentration-peaks cannot be interpreted with lateral movement or growth activities and appear to be related to environmental pollution events. Pb isotope ratios for most samples plot along the 'Chinese Pb line' and clearly document the importance of gasoline Pb as a source of contaminant. Shale-normalised REE + Y patterns are relatively flat and consistent across the growth period, with all patterns showing a positive Ce anomaly and elevated Y/Ho ratio. The positive Ce anomaly is observed regardless of the choice of normaliser, in contrast to previously reported REE patterns for terrestrial and marine plants. This pilot study of trace element, REE + Y and Pb isotope distribution in mangrove tree rings indicates the potential use of mangroves as monitors of historical environmental change.

  19. The comparison of micro elements (Mn, Fe and Zn and heavy metals (Co, Cr and Cd in the soil of perennial farms of saffron (Crocus sativus L. in southern Khorasan Province

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Behdani

    2016-05-01

    Full Text Available In order to study concentrations of soil micro and heavy metal elements in some saffron planting regions of Birjand Province, an experiment was performed as factorial layout based on a completely randomized block design with three replications at year 2013. Treatments were three field ages (annual, triennial and quinquennial and five saffron regions including Aryan shahr, Hosseinabad, Khosef, Golferiz and Mahmoei. Soil microelement and hevey methal concentrations such as Fe, Zn, Mn, Co, Cr and Cd of soil were measured. The results showed that the concentrations of Fe, Zn, Mn and Cr in soil were significantly affected by field age (p≤0.05. Effect of planting region was significant on soil Fe, Zn, Mn, Co and Cr concentrations (p≤0.01. Interaction effects between field age and planting region were significant on Fe, Zn and Co concentrations (p≤0.01. By increasing in field age soil Zn concentration was declined and heavy metal concentrations such as Co, Cr and Cd of soil were enhanced. Mn concentration in the quinquennial fields was 29 and 34% higher than annual and triennial first fields, respectively. Co content in the quinquennial fields was 53 and 46% higher than annual and triennial first fields, respectively. The maximum and minimum Fe concentrations were observed with 1.65 and 0.77 ppm for the fields of Khosef and Hosseinabad, respectively. The highest and lowest Fe concentrations were obtained with 2.436 and 0.77 ppm for the annual fields of Khosef and Hosseinabad, respectively. The highest Co concentrations were recorded in Hosseinabad and Khosef fields with 8.7 and 4.31 ppm, respectively. Thus, it is recommended to use ecological managemens such as reducing the application of chemical fertilizers and improving the organic fertilizers to decline the concentrations of these elements in saffron fields.

  20. Carbon based secondary compounds do not provide protection against heavy metal road pollutants in epiphytic macrolichens.

    Science.gov (United States)

    Gauslaa, Yngvar; Yemets, Olena A; Asplund, Johan; Solhaug, Knut Asbjørn

    2016-01-15

    Lichens are useful monitoring organisms for heavy metal pollution. They are high in carbon based secondary compounds (CBSCs) among which some may chelate heavy metals and thus increase metal accumulation. This study quantifies CBSCs in four epiphytic lichens transplanted for 6months on stands along transects from a highway in southern Norway to search for relationships between concentrations of heavy metals and CBSCs along a gradient in heavy metal pollutants. Viability parameters and concentrations of 21 elements including nutrients and heavy metals in these lichen samples were reported in a separate paper. Medullary CBSCs in fruticose lichens (Ramalina farinacea, Usnea dasypoga) were reduced in the most polluted sites, but not in foliose ones (Parmelia sulcata, Lobaria pulmonaria), whereas cortical CBSC did not change with distance from the road in any species. Strong positive correlations only occurred between the major medullary compound stictic acid present in L. pulmonaria and most heavy metals, consistent with a chelating role of stictic acid, but not of other studied CBSCs or in other species. However, heavy metal chelating did not protect L. pulmonaria against damage because this species experienced the strongest reduction in viability in the polluted sites. CBSCs with an accumulation potential for heavy metals should be quantified in lichen biomonitoring studies of heavy metals because they, like stictic acid, could overshadow pollutant inputs in some species rendering biomonitoring data less useful. In the two fruticose lichen species, CBSCs decreased with increasing heavy metal concentration, probably because heavy metal exposure impaired secondary metabolism. Thus, we found no support for a heavy metal protection role of any CBSCs in studied epiphytic lichens. No intraspecific relationships occurred between CBSCs versus N or C/N-ratio. Interspecifically, medullary CBSCs decreased and cortical CBSCs increased with increasing C/N-ratio. Copyright © 2015

  1. Heavy-Load Lifting

    DEFF Research Database (Denmark)

    Bloomquist, Kira; Oturai, Peter; Steele, Megan L

    2017-01-01

    PURPOSE: Despite a paucity of evidence, prevention guidelines typically advise avoidance of heavy lifting in an effort to protect against breast cancer-related lymphedema. This study compared acute responses in arm swelling and related symptoms after low- and heavy-load resistance exercise among...... women at risk of lymphedema while receiving adjuvant taxane-based chemotherapy. METHODS: This is a randomized, cross-over equivalence trial. Women receiving adjuvant taxane-based chemotherapy for breast cancer who had undergone axillary lymph node dissection (n=21) participated in low- (60-65% 1...... repetition maximum (RM), two sets of 15-20 repetitions) and heavy-load (85-90% 1RM, three sets of 5-8 repetition) upper-extremity resistance exercise separated by a one-week wash-out period. Swelling was determined by bioimpedance spectroscopy and dual energy x-ray absorptiometry, with breast cancer...

  2. Redox status and heavy metal risk in intertidal sediments in NW Spain as inferred from the degrees of pyritization of iron and trace elements.

    Science.gov (United States)

    Alvarez-Iglesias, P; Rubio, B

    2009-04-01

    Mariculture is an important economic activity in shallow marine areas of the Rías Baixas (Galicia, NW Spain). The maintenance of high product quality requires surveillance of environmental quality, including the risk of metal toxicity. In this study the redox status of intertidal sediments in the Bay of San Simón, and the risk of toxicity posed by their As, Cd, Cr, Cu, Mn, Ni, Pb and Zn contents, were evaluated by determination of operationally defined reactive, silicate-bound, organic and pyrite-related fractions of these elements and of Fe. The large silicate-bound fractions of most of these metals indicate their lithogenic origin; the main exception is Pb, which in all respects exhibits singular behaviour associated with its predominantly anthropogenic origin in a ceramics factory. In sediments with larger fine-grained particle contents, which are oxic only in the top few centimetres, greater proportions of the trace elements are present as sulphides or associated with sulphide minerals: the degree of pyritization of Fe (DOP) is 46% overall, and the pyrite fraction of some elements doubtless increases at the expense of the reactive fraction, most overall degrees of trace metal pyritization (DTMPs) lying in the range 10-50%. A decline in pyrite genesis at depths below about 18 cm in these sediments is attributed to the exhaustion of organic matter susceptible to metabolization by sulphide-generating bacteria. In coarse-grained, oxic sediments the oxidation of sulphides makes pyrite-related fractions very small, and reactive and silicate-bound fractions are negatively correlated; reactive fractions associated with Fe-Mn oxyhydroxides are large, and DOP and DTMPs are low (generally much lower than in mud-rich sediments), except for Pb. Most of the elements studied are mainly present in forms that are neither bioavailable nor potentially bioavailable, and so do not constitute a significant environmental threat. However, the high DTMPs of Cu and Pb indicate

  3. Excitation energies, singlet-triplet energy gaps, spin-orbit matrix elements and heavy atom effects in BOIMPYs as possible photosensitizers for photodynamic therapy: a computational investigation.

    Science.gov (United States)

    De Simone, Bruna Clara; Mazzone, Gloria; Russo, Nino; Sicilia, Emilia; Toscano, Marirosa

    2018-01-24

    Bis(borondifluoride)-8-imidazodipyrromethene (BOIMPY) based molecules show interesting photophysical properties. We have undertaken a computational study at DFT and TDDFT levels of theory with the aim of verifying if the non-fluorescent BOIMPYs meet those properties necessary to be proposed as potential photosensitizers for photodynamic therapy (PDT). In particular, we have computed the absorption wavelengths, the singlet-triplet energy gaps and the spin-orbit matrix elements. The effect of halogen atom substitution (Br, I), in different amounts and positions in the BOIMPY skeleton, on the photophysical properties, has been elucidated. Some possible pathways for the population of the lowest triplet state have been examined and rationalized on the basis of Kasha rules. The results indicate that many of the studied systems can be indicated as potential photosensitizers for photodynamic therapy.

  4. L X-ray fluorescence cross-sections of heavy elements excited by 16.04, 16.90 and 17.78 keV photons

    Energy Technology Data Exchange (ETDEWEB)

    Al-Saleh, K.A. [Department of Physics, University of Jordan, P.O. Box 13099, Amman (Jordan); Saleh, N.S. [Department of Physics, University of Jordan, P.O. Box 13099, Amman (Jordan)

    1999-01-01

    L{sub l}, L{sub {alpha}}, L{sub {beta}}, L{sub {gamma}} X-ray fluorescence cross sections have been measured for the elements Au, Pt, W, Lu, Yb, Tm, Ho, Dy and Tb using photon energies of 16.04, 16.90 and 17.78 keV. Measurements have been performed using an X-ray tube with a secondary-exciter system as an excitation source. The secondary exciters used are Zr, Nb and Mo of pure metal sheets (99.99%). A Mo X-ray tube with a secondary-target arrangement was used to obtain high intensity with a high degree of monochromaticity. Using an X-ray tube made it possible to measure X-ray fluorescence cross-sections and intensity ratios even for low intensity X-ray lines. The experimental values of the cross-sections were determined by measuring the absolute yield of L subshell X-rays emitted from a standard target of a given element irradiated with photons of given energy. The theoretical values of the cross-sections were calculated using theoretically tabulated values of subshell photoionization cross-sections, fluorescence yields, Coster-Kronig transition probabilities and radiative decay rates. Experimental results have been compared with the theoretically calculated values of L X-ray cross-sections. A fairly good agreement is observed between the experimental and the calculated values. The intensity ratios I{sub L{beta}}/I{sub L{alpha}} and I{sub L{gamma}}/I{sub L{alpha}} were measured and found to be in good agreement with the calculated values.

  5. Trace amounts of rare earth elements in high purity samarium oxide by sector field inductively coupled plasma mass spectrometry after separation by HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Pedreira, W.R. [Instituto de Geociencias, Universidade de Brasilia (UnB), 70910-900 Brasilia, DF (Brazil) and Fundacao Jorge Duprat Figueiredo de Seguranca e Medicina do Trabalho (FUNDACENTRO), 05409-002 Sao Paulo, SP (Brazil)]. E-mail: walter.pedreira@fundacentro.gov.br; Queiroz, C.A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), 05508-900 Sao Paulo, SP (Brazil); Abrao, A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), 05508-900 Sao Paulo, SP (Brazil); Rocha, S.M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), 05508-900 Sao Paulo, SP (Brazil); Vasconcellos, M.E. de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), 05508-900 Sao Paulo, SP (Brazil); Boaventura, G.R. [Instituto de Geociencias, Universidade de Brasilia (UnB), 70910-900 Brasilia, DF (Brazil); Pimentel, M.M. [Instituto de Geociencias, Universidade de Brasilia (UnB), 70910-900 Brasilia, DF (Brazil)

    2006-07-20

    Today there is an increasing need for high purity rare earth compounds in various fields, the optical, the electronics, the ceramic, the nuclear and geochemistry. Samarium oxide has special uses in glass, phosphors, lasers and thermoelectric devices. Calcium chloride crystals treated with samarium have been employed in lasers, which produce light beams intense enough to burn metal. In general, the inductively coupled plasma mass spectrometry (ICP-MS) presents some advantages for trace element analysis, due to high sensitivity and resolution, when compared with other analytical techniques such as ICP optical emission spectrometry (ICP-OES). In this work, sector field inductively coupled plasma mass spectrometry was used. Sixteen elements (Sc, Y and 14 lanthanides) were determined selectively with the ICP-MS system using a concentration gradient method. The detection limits with the ICP-MS system were about 0.2 (La) pg mL{sup -1} to 8 (Gd) pg mL{sup -1}. The %R.S.D. of the methods varying between 0.9 and 1.5% for a set of five (n = 5) replicates was found for the IPEN's material and for the certificate reference sample. Determination of trace REEs in two high pure samarium oxides samples (IPEN and JMC) was performed. IPEN's material is highly pure (>99.99%) and was successfully analyzed without spectral interference (MO{sup +} and MOH{sup +})

  6. The Influence of Lactic Acid Concentration on the Separation of Light Rare Earth Elements by Continuous Liquid-Liquid Extraction with 2-Ethylhexyl Phosphonic Acid Mono-2-ethylhexyl Ester

    Science.gov (United States)

    de Carvalho Gomes, Rafael; Seruff, Luciana Amaral; Scal, Maira Labanca Waineraich; Vera, Ysrael Marrero

    2018-02-01

    The separation of rare earth elements (REEs) using solvent extraction adding complexing agents appears to be an alternative to saponification of the extractant. We evaluated the effect of lactic acid concentration on didymium (praseodymium and neodymium) and lanthanum extraction with 2-ethylhexyl phosphonic acid mono-2-ethyl hexyl ester [HEH(EHP)] as extractant. First, we investigated in batch experiments the separation of lanthanum (La) and didymium (Pr and Nd) using McCabe-Thiele diagrams to estimate the number of extraction stages when the feed solution was or was not conditioned with lactic acid. Additionally, we conducted continuous liquid-liquid extraction experiments and evaluated the influence of lactic acid concentration on the REE extraction and separation. The tests showed that the extraction percentage of REEs and the separation factor Pr/La increased when the lactic acid concentration increased, but the didymium purity decreased. Lanthanum, praseodymium, and neodymium extraction rate were 23.0, 89.7, and 99.2 pct, respectively, with 1:1 aqueous/organic volume flow rate and feed solution doped with 0.52 mol L-1 lactic acid. The highest didymium purity reached was 92.0 pct with 0.26 mol L-1 lactic acid concentration.

  7. The Influence of Lactic Acid Concentration on the Separation of Light Rare Earth Elements by Continuous Liquid-Liquid Extraction with 2-Ethylhexyl Phosphonic Acid Mono-2-ethylhexyl Ester

    Science.gov (United States)

    de Carvalho Gomes, Rafael; Seruff, Luciana Amaral; Scal, Maira Labanca Waineraich; Vera, Ysrael Marrero

    2017-11-01

    The separation of rare earth elements (REEs) using solvent extraction adding complexing agents appears to be an alternative to saponification of the extractant. We evaluated the effect of lactic acid concentration on didymium (praseodymium and neodymium) and lanthanum extraction with 2-ethylhexyl phosphonic acid mono-2-ethyl hexyl ester [HEH(EHP)] as extractant. First, we investigated in batch experiments the separation of lanthanum (La) and didymium (Pr and Nd) using McCabe-Thiele diagrams to estimate the number of extraction stages when the feed solution was or was not conditioned with lactic acid. Additionally, we conducted continuous liquid-liquid extraction experiments and evaluated the influence of lactic acid concentration on the REE extraction and separation. The tests showed that the extraction percentage of REEs and the separation factor Pr/La increased when the lactic acid concentration increased, but the didymium purity decreased. Lanthanum, praseodymium, and neodymium extraction rate were 23.0, 89.7, and 99.2 pct, respectively, with 1:1 aqueous/organic volume flow rate and feed solution doped with 0.52 mol L-1 lactic acid. The highest didymium purity reached was 92.0 pct with 0.26 mol L-1 lactic acid concentration.

  8. LAMOST telescope reveals that Neptunian cousins of hot Jupiters are mostly single offspring of stars that are rich in heavy elements.

    Science.gov (United States)

    Dong, Subo; Xie, Ji-Wei; Zhou, Ji-Lin; Zheng, Zheng; Luo, Ali

    2018-01-09

    We discover a population of short-period, Neptune-size planets sharing key similarities with hot Jupiters: both populations are preferentially hosted by metal-rich stars, and both are preferentially found in Kepler systems with single-transiting planets. We use accurate Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Data Release 4 (DR4) stellar parameters for main-sequence stars to study the distributions of short-period [Formula: see text] Kepler planets as a function of host star metallicity. The radius distribution of planets around metal-rich stars is more "puffed up" compared with that around metal-poor hosts. In two period-radius regimes, planets preferentially reside around metal-rich stars, while there are hardly any planets around metal-poor stars. One is the well-known hot Jupiters, and the other one is a population of Neptune-size planets ([Formula: see text]), dubbed "Hoptunes." Also like hot Jupiters, Hoptunes occur more frequently in systems with single-transiting planets although the fraction of Hoptunes occurring in multiples is larger than that of hot Jupiters. About [Formula: see text] of solar-type stars host Hoptunes, and the frequencies of Hoptunes and hot Jupiters increase with consistent trends as a function of [Fe/H]. In the planet radius distribution, hot Jupiters and Hoptunes are separated by a "valley" at approximately Saturn size (in the range of [Formula: see text]), and this "hot-Saturn valley" represents approximately an order-of-magnitude decrease in planet frequency compared with hot Jupiters and Hoptunes. The empirical "kinship" between Hoptunes and hot Jupiters suggests likely common processes (migration and/or formation) responsible for their existence.

  9. Density/area power-law models for separating multi-scale anomalies of ore and toxic elements in stream sediments in Gejiu mineral district, Yunnan Province, China

    Science.gov (United States)

    Cheng, Q.; Xia, Q.; Li, W.; Zhang, S.; Chen, Z.; Zuo, R.; Wang, W.

    2010-10-01

    This contribution introduces a fractal filtering technique newly developed on the basis of a spectral energy density vs. area power-law model in the context of multifractal theory. It can be used to map anisotropic singularities of geochemical landscapes created from geochemical concentration values in various surface media such as soils, stream sediments, tills and water. A geochemical landscape can be converted into a Fourier domain in which the spectral energy density is plotted against the area (in wave number units), and the relationship between the spectrum energy density (S) and the area (A) enclosed by the above-threshold spectrum energy density can be fitted by power-law models. Mixed geochemical landscape patterns can be fitted with different S-A power-law models in the frequency domain. Fractal filters can be defined according to these different S-A models and used to decompose the geochemical patterns into components with different self-similarities. The fractal filtering method was applied to a geochemical dataset from 7,349 stream sediment samples collected from Gejiu mineral district, which is famous for its word-class tin and copper production. Anomalies in three different scales were decomposed from total values of the trace elements As, Sn, Cu, Zn, Pb, and Cd. These anomalies generally correspond to various geological features and geological processes such as sedimentary rocks, intrusions, fault intersections and mineralization.

  10. Density/area power-law models for separating multi-scale anomalies of ore and toxic elements in stream sediments in Gejiu mineral district, Yunnan Province, China

    Directory of Open Access Journals (Sweden)

    Q. Cheng

    2010-10-01

    Full Text Available This contribution introduces a fractal filtering technique newly developed on the basis of a spectral energy density vs. area power-law model in the context of multifractal theory. It can be used to map anisotropic singularities of geochemical landscapes created from geochemical concentration values in various surface media such as soils, stream sediments, tills and water. A geochemical landscape can be converted into a Fourier domain in which the spectral energy density is plotted against the area (in wave number units, and the relationship between the spectrum energy density (S and the area (A enclosed by the above-threshold spectrum energy density can be fitted by power-law models. Mixed geochemical landscape patterns can be fitted with different S-A power-law models in the frequency domain. Fractal filters can be defined according to these different S-A models and used to decompose the geochemical patterns into components with different self-similarities. The fractal filtering method was applied to a geochemical dataset from 7,349 stream sediment samples collected from Gejiu mineral district, which is famous for its word-class tin and copper production. Anomalies in three different scales were decomposed from total values of the trace elements As, Sn, Cu, Zn, Pb, and Cd. These anomalies generally correspond to various geological features and geological processes such as sedimentary rocks, intrusions, fault intersections and mineralization.

  11. Research reactor fuel element corrosion under repository relevant conditions. Separation, identification, and quantification of secondary alteration phases of UAl{sub x}-Al in MgCl{sub 2}-rich brine

    Energy Technology Data Exchange (ETDEWEB)

    Klinkenberg, M.; Neumann, A.; Curtius, H.; Kaiser, G.; Bosbach, D. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Energie und Klimaforschung (IEK-6), Nukleare Entsorgung und Reaktorsicherheit

    2014-07-01

    The corrosion of the UAl{sub x}-Al research reactor fuel type in synthetic MgCl{sub 2}-rich brine (static batch-type experiments) was investigated with respect to the long-term safety of directly disposed research reactor fuel elements in salt formations. During corrosion, crystalline secondary phases were formed, which may serve as a barrier against radionuclide migration. For an optimized identification and quantification of the secondary phases using X-ray diffraction, a sample treatment to separate and enrich the secondary phases is necessary. A grain size fractionation was carried out in iso-propanol. A chemical composition and phase characterization of the secondary phases was accomplished. The results of the chemical investigations reveal that only traces of Al and U were dissolved. The separation and enrichment of secondary phases were carried out reproducible and successfully. Due to the phase characterization by scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray diffraction the following secondary phases were unambiguously identified: Mg-Al-Cl layered double hydroxide, lesukite, Fe layered double hydroxide (green rust), lawrencite, Fe (elemental), and traces of uncorroded fuel (UAl{sub 4}). The quantitative analysis showed that LDH compounds and lesukite are the major crystalline phases. All other observed compounds were only present in trace amounts, i.e. constituting accessories. The Rietveld analysis also revealed the high content of amorphous phases of approximately 30%, which are expected to include the uranium as U(OH){sub 4}.

  12. A compilation of field surveys on gaseous elemental mercury (GEM) from contrasting environmental settings in Europe, South America, South Africa and China: separating fads from facts.

    Science.gov (United States)

    Higueras, Pablo; Oyarzun, Roberto; Kotnik, Joze; Esbrí, José María; Martínez-Coronado, Alba; Horvat, Milena; López-Berdonces, Miguel Angel; Llanos, Willians; Vaselli, Orlando; Nisi, Barbara; Mashyanov, Nikolay; Ryzov, Vladimir; Spiric, Zdravko; Panichev, Nikolay; McCrindle, Rob; Feng, Xinbin; Fu, Xuewu; Lillo, Javier; Loredo, Jorge; García, María Eugenia; Alfonso, Pura; Villegas, Karla; Palacios, Silvia; Oyarzún, Jorge; Maturana, Hugo; Contreras, Felicia; Adams, Melitón; Ribeiro-Guevara, Sergio; Niecenski, Luise Felipe; Giammanco, Salvatore; Huremović, Jasna

    2014-08-01

    Mercury is transported globally in the atmosphere mostly in gaseous elemental form (GEM, [Formula: see text]), but still few worldwide studies taking into account different and contrasted environmental settings are available in a single publication. This work presents and discusses data from Argentina, Bolivia, Bosnia and Herzegovina, Brazil, Chile, China, Croatia, Finland, Italy, Russia, South Africa, Spain, Slovenia and Venezuela. We classified the information in four groups: (1) mining districts where this contaminant poses or has posed a risk for human populations and/or ecosystems; (2) cities, where the concentration of atmospheric mercury could be higher than normal due to the burning of fossil fuels and industrial activities; (3) areas with natural emissions from volcanoes; and (4) pristine areas where no anthropogenic influence was apparent. All the surveys were performed using portable LUMEX RA-915 series atomic absorption spectrometers. The results for cities fall within a low GEM concentration range that rarely exceeds 30 ng m(-3), that is, 6.6 times lower than the restrictive ATSDR threshold (200 ng m(-3)) for chronic exposure to this pollutant. We also observed this behavior in the former mercury mining districts, where few data were above 200 ng m(-3). We noted that high concentrations of GEM are localized phenomena that fade away in short distances. However, this does not imply that they do not pose a risk for those working in close proximity to the source. This is the case of the artisanal gold miners that heat the Au-Hg amalgam to vaporize mercury. In this respect, while GEM can be truly regarded as a hazard, because of possible physical-chemical transformations into other species, it is only under these localized conditions, implying exposure to high GEM concentrations, which it becomes a direct risk for humans.

  13. Real-time mode detection of heavy ion-induced nuclear reaction products

    CERN Document Server

    Tsyganov, Yu S; Polyakov, A N; Yakushev, A B; Vakatov, V I

    2002-01-01

    Design of spectrometers of two nuclear research facilities, the Dubna Gas-filled Recoil Separator and KHIPTI is reviewed. The sources of backgrounds are discussed and techniques used to suppress these backgrounds in one-event detection experiments aimed at the synthesis of heavy elements are presented. The first system was used in 1998 in experiments on Z=114 superheavy element. We consider the possibility of detection of rare time and position correlated recoil-alpha and alpha-alpha sequences in real-time mode as basic techniques to suppress beam and target-like associated backgrounds. Fields of application of such a technique are discussed from the viewpoint of synthesis of heavy elements and by studying their chemical properties.

  14. Element 115

    OpenAIRE

    Forsberg, Ulrika

    2016-01-01

    This thesis is devoted to detailed studies of element 115 decay chains using the highly efficient multi-coincidence alpha, electron, gamma and X-ray detector setup TASISpec at the gas-filled separator TASCA at GSI, Darmstadt, Germany. In a three-week long experiment thirty new decay chains assumed to stem from element 115 isotopes were observed together with the very first detections of gamma rays and potential X-rays from these nuclei. Paper I describes preparations in terms of optimisations...

  15. Perilous Effects of Heavy Metals Contamination on Human Health

    OpenAIRE

    Naseem Zahra; Imran Kalim; Minahil Mahmood; Nageen Naeem

    2017-01-01

    Heavy metals form a versatile group of high density elements that vary considerably in their biological roles and chemical properties. Although many heavy metals are essential trace elements yet they have long been recognized as environmental pollutants due their toxic effects. Increased industrialization, urbanization anthropogenic activities like mining, smelting and other agricultural activities have resulted in accumulation of heavy metals in the environment. Heavy metals such as nickel, ...

  16. Symmetry-based design of fragment separator optics

    Directory of Open Access Journals (Sweden)

    B. Erdelyi

    2007-06-01

    Full Text Available Next-generation high-intensity large acceptance fragment separators require a careful design due to the large high order aberrations induced by the large aperture superconducting magnets needed to collect rare isotopes obtained from a high energy primary heavy-ion beam hitting a target. In this paper we propose a fragment separator layout based on various symmetries that satisfies the baseline requirements. Analytical calculations based on symmetry theories simplify the design to numerical optimization of a basic cell with only a few magnetic elements. The insight provided by these calculations resulted in the specification of a simple layout with large acceptance, transmission, and resolution. The design method may be easily adapted to project-specific needs. The important effects of energy degraders necessary for full fragment separator design will be addressed in a future publication.

  17. Separated Shoulder

    Science.gov (United States)

    ... an injury to the ligaments that hold your collarbone (clavicle) to your shoulder blade. In a mild separated ... tenderness or pain near the end of your collarbone. Causes The most common cause of a separated ...

  18. Heavy metal

    African Journals Online (AJOL)

    niloticus after exposure to sublethal concentrations of heavy metals such as copper, lead and zinc for a 12-week period, using static renewable toxicity tests. The concentrations of the metals accumulated in the tissue of exposed fish were about 3-5 times higher than the concentrations detected in control fish.

  19. Menorrhagia (Heavy Menstrual Bleeding)

    Science.gov (United States)

    Menorrhagia (heavy menstrual bleeding) Overview Menorrhagia is the medical term for menstrual periods with abnormally heavy or prolonged bleeding. Although heavy menstrual bleeding is a common concern, ...

  20. Electrochemical attributes and availability of nutrients, toxic elements, and heavy metals in tropical soils Atributos eletroquímicos e disponibilidade de nutrientes, elementos tóxicos e metais pesados em solos tropicais

    Directory of Open Access Journals (Sweden)

    Mauricio Paulo Ferreira Fontes

    2006-12-01

    Full Text Available Electrochemical properties of soils are very important for the understanding of the physico-chemical phenomena which affect soil fertility and the availability of nutrients for plants. This review highlights the electrochemical properties of tropical soils, the behavior and the availability of nutrients, toxic elements and heavy metals in the soil, especially for soils with predominant variable charge minerals. Availability of the elements is related to ionic exchange, solution speciation, and electrostatic and specific adsorptive soil properties. Empirical and surface complexation models are briefly described, and some results of their application in tropical soils are presented. A better understanding of the role of the double diffuse layer of charges and CEC on nutrient cation availability for highly weathered soils is required, as well as a solid comprehension of surface complexation models, in order to improve the knowledge regarding the behavior of anions in soils. More studies have to be conducted to generate results that enable the use of chemical speciation concepts and calculation of several constants used in surface complexation models, especially for highly weathered soils from the humid tropics. There has to be a continuing development and use of computer softwares that have already incorporated the concepts of chemical speciation and adsorption models in the study of nutrients, toxic elements and heavy metal availability in the soil-plant system.As propriedades eletroquímicas dos solos tropicais são muito importantes para entendimento dos fenômenos físico-químicos que afetam a fertilidade do solo e a disponibilidade dos nutrientes das plantas. Essa revisão destaca os atributos eletroquímicos de solos e o comportamento e a disponibilidade de nutrientes, elementos tóxicos e metais pesados no solo, especialmente aqueles com predominância de minerais com cargas variáveis. A disponibilidade dos elementos é relacionada com a

  1. Heavy ions: Report from Relativistic Heavy Ion Collider

    Indian Academy of Sciences (India)

    2012-10-12

    Oct 12, 2012 ... heavy flavour decays is compatible with RAA of charged mesons at high pT. Therefore, no significant mass dependence is exhibited in the data. These data challenge the theo- retical models and show the importance of a separate measurement of charm and beauty yields in Au+Au collisions at RHIC, ...

  2. Redox speciation of final repository relevant elements using separation methods in combination with ICP mass spectrometry; Redoxspeziation von endlagerrelevanten Elementen mit Hilfe von Trennmethoden gekoppelt an ein Massenspektrometer mit induktiv gekoppeltem Plasma

    Energy Technology Data Exchange (ETDEWEB)

    Graser, Carl-Heinrich

    2015-12-18

    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{sup -6} mol.L{sup -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{sup -7} mol.L{sup -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{sup -12} mol.L{sup -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

  3. Trace elements determination in high salinity petroleum produced formation water by high-resolution continuum source graphite furnace atomic absorption spectrometry after matrix separation using Chelex-100 Registered-Sign resin

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Aline Soares [Departamento de Geoquimica, Universidade Federal Fluminense, Outeiro Sao Joao Batista s/n, Centro, Niteroi/RJ, 24020-150 (Brazil); Departamento de Quimica Analitica, Universidade Federal do Rio de Janeiro Av. Athos da Silveira Ramos 149, Centro de Tecnologia, Bloco A, Cidade Universitaria, Rio de Janeiro/RJ, 21941-909 (Brazil); Santelli, Ricardo Erthal, E-mail: santelli@iq.ufrj.br [Departamento de Geoquimica, Universidade Federal Fluminense, Outeiro Sao Joao Batista s/n, Centro, Niteroi/RJ, 24020-150 (Brazil); Departamento de Quimica Analitica, Universidade Federal do Rio de Janeiro Av. Athos da Silveira Ramos 149, Centro de Tecnologia, Bloco A, Cidade Universitaria, Rio de Janeiro/RJ, 21941-909 (Brazil)

    2012-05-15

    This study describes a procedure used for the determination of trace metals (Co, Cu, Mn, Ni and Pb) in high salinity petroleum produced formation water (PFW) employing high-resolution continuum source graphite furnace atomic absorption spectrometry for detection and Chelex-100 Registered-Sign resin for matrix elimination and analytes preconcentration. Using 15.0 mL of PFW for the separation/preconcentration, detection limits of 0.006, 0.07, 0.03, 0.08 and 0.02 {mu}g L{sup -1} were obtained for Co, Cu, Mn, Ni and Pb, respectively. The accuracy of the proposed method was evaluated by analyzing three seawater certified reference materials and by recovery tests, and the data indicate that the methodology can be successfully applied to this kind of samples. The precision values, expressed as relative standard deviation (% RSD, n = 10) for 2.0 {mu}g L{sup -1}, were found to be 3.5, 4.0, 9.0, 5.3 and 5.9 for Co, Cu, Mn, Ni and Pb, respectively. The proposed procedure was applied for the determination of these metals in medium and high salinity PFW samples obtained from Brazilian offshore petroleum exploration platforms. - Highlights: Black-Right-Pointing-Pointer Petroleum-produced formation water were analyzed for Co, Cu, Mn, Ni and Pb determination. Black-Right-Pointing-Pointer In batch analyte preconcentration/matrix separation using Chelex-100 Registered-Sign was used. Black-Right-Pointing-Pointer Detection limits between 0.006 and 0.08 {mu}g L{sup -1} were found by using HR-CS-GFAAS. Black-Right-Pointing-Pointer Trace elements characterization is possible using the developed method. Black-Right-Pointing-Pointer Maximum trace element concentrations found could support future Brazilian directives.

  4. On Heavy Element Enrichment in Classical Novae

    Science.gov (United States)

    Alexakis, A.; Calder, A. C.; Heger, A.; Brown, E. F.; Dursi, L. J.; Truran, J. W.; Rosner, R.; Lamb, D. Q.; Timmes, F. X.; Fryxell, B.; Zingale, M.; Ricker, P. M.; Olson, K.

    2004-02-01

    Many classical nova ejecta are enriched in CNO and Ne. Rosner and coworkers recently suggested that the enrichment might originate in the resonant interaction between large-scale shear flows in the accreted H/He envelope and gravity waves at the interface between the envelope and the underlying C/O white dwarf (WD). The shear flow amplifies the waves, which eventually form cusps and break. This wave breaking injects a spray of C/O into the superincumbent H/He. Using two-dimensional simulations, we formulate a quantitative expression for the amount of C/O per unit area that can be entrained, at saturation, into the H/He. The fraction of the envelope that is enriched depends on the horizontal distribution of shear velocity and the density contrast between the C/O WD and the H/He layer but is roughly independent of the vertical shape of the shear profile. Using this parameterization for the mixed mass, we then perform several one-dimensional Lagrangian calculations of an accreting WD envelope and consider two scenarios: that the wave breaking and mixing is driven by the convective flows and that the mixing occurs prior to the onset of convection. In the absence of enrichment prior to ignition, the base of the convective zone, as calculated from mixing-length theory with the Ledoux instability criterion, does not reach the C/O interface. As a result, there is no additional mixing, and the runaway is slow. In contrast, the formation of a mixed layer during the accretion of H/He, prior to ignition, causes a more violent runaway. The envelope can be enriched by <~25% of C/O by mass (consistent with that observed in some ejecta) for shear velocities, over the surface, with Mach numbers <~0.4.

  5. Metal-bearing Aerosols of Industrial Origin from Multiple Sources in South Phoenix, Arizona: Separating Similar Particle Types with Minor Element Differences Using Automated SEM Analysis of Large Populations of Particles

    Science.gov (United States)

    Anderson, J.; Hua, X.

    2009-12-01

    Particulate pollution, especially PM10, in the Greater Phoenix (Maricopa County) airshed is a long-standing problem. While much of the PM10 can be ascribed to soil dust entrained by human activity (e.g., sand and gravel mining and other construction-support activities both directly and indirectly), south-central and southwest Phoenix have a significant number of industrial sources of metal-bearing particles. Many of these particles are dominated compositionally by Fe but have minor elements such as Cu, Ba, Mn, Cr, Ni and others which can be statistically mutually exclusive when large populations are looked at with automated Scanning Electron Microscopy (SEM). Bulk aerosol chemical analysis of high-volume samples shows the presence of these elements, including the dominance of Fe at times, but there are far more potential sources than can ever by deduced by principal component analysis of the bulk sample data. Because of the potential toxic nature of these industrial particles, about which there is considerable community concern, identifying the multiple sources is a key step in mitigating the pollution. Also present in these industrial aerosols are mostly submicron particles containing Sr, Sb, V, Cd, and other elements in various combinations. While analyzing the minor element content of submicron particles, some of which are beam-sensitive, pushes the limits of automated SEM techniques, this is the only way to examine large, statistically significant particle populations in many samples on an individual-particle basis. The elemental associations in these unusual metal-bearing particles tend to be the key to source identification. Particle morphology is also important in separating particle types from different sources in these populations. For instance, one of major sources of Fe-dominant particles in southwest Phoenix is a scrap metal operation that uses a “mega-shredder”. This mega-shredder generates enough heat to melt some of the metal and produce roughly

  6. The relation between heavy metals distribution and particle size fractions in some egyptian soils

    Directory of Open Access Journals (Sweden)

    Monier Morad Wahba

    Full Text Available Soil as a part of the environment receives pollutants from all types of human activities. Heavy metals originating from various organic waste sources and industrial activities accumulate in the soil surface, and their fate depends not only on the types and amounts of waste applied, but on soil properties. Furthermore, soils differ in their retention power for various heavy or trace elements. Twelve soil samples were selected from different sites irrigated with industrial and sewage wastes at Helwan city (Cairo Governorate in the north and El-Saff (Giza Governorate in the south. Separation of clay, silt and sand fractions were carried out. Chemical analyses of trace elements in the form of total and available contents (Fe, Mn, Zn and Pb were determined in each fraction. The obtained results show that the average amounts of heavy metals in different fractions are related to the particle size of the soil especially the fine fraction. Heavy metals content was always in the surface layers higher than sub-surface. All metals were highest in clay fraction followed by silt and sand fractions respectively. This investigation discussed the importance of the fine fractions in the accumulation of heavy metals by coordination number in the lattice structure.

  7. SELECTIVE SEPARATION, PRECONCENTRATION AND ...

    African Journals Online (AJOL)

    B. S. Chandravanshi

    The developed coprecipitation procedure has been applied to road dust, anodic slime, industrial electronic waste materials and water samples to determine their Pd(II) levels. KEY WORDS: Palladium, Separation, Preconcentration, Carrier element free coprecipitation. INTRODUCTION. Palladium, a precious metal, is widely ...

  8. Arbuscular Mycorrhizal Fungi Can Benefit Heavy Metal Tolerance and Phytoremediation

    Science.gov (United States)

    Forgy, David

    2012-01-01

    Sites contaminated by heavy metals, such as industrial waste sites, create unwelcoming environments for plant growth. Heavy metals can have a wide range of toxic effects such as replacing essential elements or disrupting enzyme function. While some heavy metals are essential to plant nutrition at low concentrations, high concentrations of any…

  9. CENTRIFUGAL SEPARATORS

    Science.gov (United States)

    Skarstrom, C.

    1959-03-10

    A centrifugal separator is described for separating gaseous mixtures where the temperature gradients both longitudinally and radially of the centrifuge may be controlled effectively to produce a maximum separation of the process gases flowing through. Tbe invention provides for the balancing of increases and decreases in temperature in various zones of the centrifuge chamber as the result of compression and expansions respectively, of process gases and may be employed effectively both to neutralize harmful temperature gradients and to utilize beneficial temperaturc gradients within the centrifuge.

  10. Disentangling heavy flavor at colliders

    Science.gov (United States)

    Ilten, Philip; Rodd, Nicholas L.; Thaler, Jesse; Williams, Mike

    2017-09-01

    We propose two new analysis strategies for studying charm and beauty quarks at colliders. The first strategy is aimed at testing the kinematics of heavy-flavor quarks within an identified jet. Here, we use the SoftDrop jet-declustering algorithm to identify two subjets within a large-radius jet, using subjet flavor tagging to test the heavy-quark splitting functions of QCD. For subjets containing a J /ψ or ϒ , this declustering technique can also help probe the mechanism for quarkonium production. The second strategy is aimed at isolating heavy-flavor production from gluon splitting. Here, we introduce a new FlavorCone algorithm, which smoothly interpolates from well-separated heavy-quark jets to the gluon-splitting regime where jets overlap. Because of its excellent ability to identify charm and beauty hadrons, the LHCb detector is ideally suited to pursue these strategies, though similar measurements should also be possible at ATLAS and CMS. Together, these SoftDrop and FlavorCone studies should clarify a number of aspects of heavy-flavor physics at colliders, and provide crucial information needed to improve heavy-flavor modeling in parton-shower generators.

  11. Heavy metal removal using nanoscale zero-valent iron (nZVI): Theory and application

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shaolin, E-mail: lishaolin@tongji.edu.cn; Wang, Wei; Liang, Feipeng; Zhang, Wei-xian, E-mail: zhangwx@tongji.edu.cn

    2017-01-15

    Highlights: • nZVI is able to perform fast and simultaneous removal of different heavy metal ions. • Fast separation and seeding effect of nZVI facilities its application in wastewater. • A novel process of E{sub h}-controlled reactor, nZVI separator and reuse is proposed. • E{sub h}-controlled system and nZVI recirculation increase material efficiency of nZVI. • The process produces stable effluent and is effective in wastewater treatment. - Abstract: Treatment of wastewater containing heavy metals requires considerations on simultaneous removal of different ions, system reliability and quick separation of reaction products. In this work, we demonstrate that nanoscale zero-valent iron (nZVI) is an ideal reagent for removing heavy metals from wastewater. Batch experiments show that nZVI is able to perform simultaneous removal of different heavy metals and arsenic; reactive nZVI in uniform dispersion brings rapid changes in solution E{sub h}, enabling a facile way for reaction regulation. Microscope characterizations and settling experiments suggest that nZVI serves as solid seeds that facilitate products separation. A treatment process consisting of E{sub h}-controlled nZVI reaction, gravitational separation and nZVI recirculation is then demonstrated. Long-term (>12 months) operation shows that the process achieves >99.5% removal of As, Cu and a number of other toxic elements. The E{sub h}-controlled reaction system sustains a highly-reducing condition in reactor and reduces nZVI dosage. The process produces effluent of stable quality that meets local discharge guidelines. The gravitational separator shows high efficacy of nZVI recovery and the recirculation improves nZVI material efficiency, resulting in extraordinarily high removal capacities ((245 mg As + 226 mg-Cu)/g-nZVI). The work provides proof that nanomaterials can offer truly green and cost-effective solutions for wastewater treatment.

  12. Longitudinal heavy quark structure function

    Energy Technology Data Exchange (ETDEWEB)

    Khorramian, Ali N. [Physics Department, Semnan University, Semnan (Iran, Islamic Republic of); School of Particles and Accelerators, IPM - Institute for Studies in Theoretical Physics and Mathematics, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)], E-mail: khorramiana@theory.ipm.ac.ir; Atashbar Tehrani, S. [Physics Department, Semnan University, Semnan (Iran, Islamic Republic of); School of Particles and Accelerators, IPM - Institute for Studies in Theoretical Physics and Mathematics, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)], E-mail: atashbar@ipm.ir; Mirjalili, A. [Physics Department, Yazd University, Yazd (Iran, Islamic Republic of); School of Particles and Accelerators, IPM - Institute for Studies in Theoretical Physics and Mathematics, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)], E-mail: mirjalili@ipm.ir

    2009-01-15

    In this paper we study the heavy-quark contribution to the proton non-singlet structure functions F{sub L}{sup NS}(x,Q{sup 2}). In this way we use very recently results for massive operator matrix elements, which contribute to the heavy flavor Wilson coefficients in unpolarized deeply inelastic scattering in the region Q{sup 2}>>m{sup 2}. The method of QCD analysis of non-singlet structure function, based on their Jacobi polynomials reconstruction from perturbative QCD predictions for the Mellin moments, is also described.

  13. Nuclear astrophysics and the Daresbury Recoil Separator at the Holifield Radioactive Ion Beam Facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.S.

    1997-12-01

    The Daresbury Recoil Separator (DRS) has been installed for nuclear astrophysics research at Oak Ridge National Laboratory`s Holifield Radioactive Ion Beam Facility. It will be used for direct measurements of capture reactions on radioactive ions which occur in stellar explosions such as novae, supernovae and X-ray bursts. These measurements will be made in inverse kinematics with radioactive heavy ion beams incident on hydrogen and helium targets, and the DRS will separate the capture reaction recoils from the intense flux of beam particles. Details of the new DRS experimental equipment and preliminary results from the first commissioning experiments with stable beams are described, along with the plans for the first measurements with radioactive beams. Other astrophysics research efforts at ORNL--in theoretical astrophysics, nuclear astrophysics data evaluation, heavy element nucleosynthesis, theoretical atomic astrophysics, and atomic astrophysics data--are also briefly described.

  14. On-Line Mass Separator of Superheavy Atoms

    CERN Document Server

    Oganessian, Yu T

    2002-01-01

    The concept is presented of an on-line Mass Analyzer of SuperHeavy Atoms (MASHA) dedicated to the separation and determination of the mass and decay properties of new elements and isotopes produced in heavy-ion induced reactions. The new nuclides with half-lives T_{1/2}\\ge 1 s are transported to an ECR-source working at a frequency of 2.45 GHz and are separated by mass with a mass resolution of M/\\Delta M\\sim 1500. In the focal plane of the magnetic analyzer a front strip detector surrounded by side detectors will be placed to determine the mass according to the signals from the detected alpha-particles or fission fragments with efficiency of about 90 %. In comparison to other existing in-flight recoil separators, the present setup will be characterized by higher efficiency and high selectivity relative to background reaction products. The setup MASHA may be used also in the investigation of nuclear reactions of different type induced by stable and radioactive beams.

  15. Removal of heavy metals from biowaste : modelling of heavy metal behaviour and development of removal technologies

    NARCIS (Netherlands)

    Veeken, A.H.M.

    1998-01-01

    In the Netherlands, recycling of solid organic waste streams as compost only becomes possible if the compost complies with the heavy metals standards of the BOOM decree. This dissertation focuses on the removal of heavy metals from biowaste, i.e. the source separated organic fraction of

  16. Recovering heavy rare earth metals from magnet scrap

    Science.gov (United States)

    Ott, Ryan T.; McCallum, Ralph W.; Jones, Lawrence L.

    2017-08-08

    A method of treating rare earth metal-bearing permanent magnet scrap, waste or other material in a manner to recover the heavy rare earth metal content separately from the light rare earth metal content. The heavy rare earth metal content can be recovered either as a heavy rare earth metal-enriched iron based alloy or as a heavy rare earth metal based alloy.

  17. X-ray fluorescence spectroscopic determination of heavy metals and ...

    African Journals Online (AJOL)

    Purpose: To determine the heavy metal and trace element composition of the powdered aerial parts of Origanum sipyleum L. and its water extract. Methods: The heavy metal and trace elements content of the powdered plant material and 2 % aqueous extract were evaluated by x-ray fluorescence spectroscopy with silicon ...

  18. Geochemistry of dark coastal heavy-mineral beaches sand (Annaba ...

    African Journals Online (AJOL)

    Acer

    correlation between the concentration of major, traces and REE elements and the amount of heavy and especially metamorphic minerals like garnet, staurolite, tourmaline and epidote. Key words: Heavy minerals- Major - Trace element – REE- Sand-Beach. * Corresponding Author: Chemam.asma@gmail.com ...

  19. X-ray fluorescence spectroscopic determination of heavy metals and ...

    African Journals Online (AJOL)

    Purpose: To determine the heavy metal and trace element composition of the powdered aerial parts of. Origanum sipyleum L. and its water extract. Methods: The heavy metal and trace elements content of the powdered plant material and 2 % aqueous extract were evaluated by x-ray fluorescence spectroscopy with silicon ...

  20. 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.

  1. Chemistry of superheavy elements

    Energy Technology Data Exchange (ETDEWEB)

    Schaedel, M. [Japan Atomic Energy Agency, Tokai, Ibaraki (Japan). Advanced Science Research Center; GSI Helmholtz Center for Heavy Ion Research, Darmstadt (Germany)

    2012-07-01

    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.)

  2. ISOTOPE SEPARATORS

    Science.gov (United States)

    Bacon, C.G.

    1958-08-26

    An improvement is presented in the structure of an isotope separation apparatus and, in particular, is concerned with a magnetically operated shutter associated with a window which is provided for the purpose of enabling the operator to view the processes going on within the interior of the apparatus. The shutier is mounted to close under the force of gravity in the absence of any other force. By closing an electrical circuit to a coil mouated on the shutter the magnetic field of the isotope separating apparatus coacts with the magnetic field of the coil to force the shutter to the open position.

  3. Elements in biological AMS

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, J.S.; McAninch, J.; Freeman, S.

    1996-08-01

    AMS (Accelerator Mass Spectrometry) provides high detection sensitivity for isotopes whose half-lives are between 10 years and 100 million years. {sup 14}C is the most developed of such isotopes and is used in tracing natural and anthropogenic organic compounds in the Earth`s biosphere. Thirty-three elements in the main periodic table and 17 lanthanides or actinides have long lived isotopes, providing potential tracers for research in elemental biochemistry. Overlap of biologically interesting heavy elements and possible AMS tracers is discussed.

  4. Heavy flavour in ALICE

    CERN Document Server

    Pillot, Philippe

    2008-01-01

    Open heavy flavours and heavy quarkonium states are expected to provide essential informa- tion on the properties of the strongly interacting system fo rmed in the early stages of heavy-ion collisions at very high energy density. Such probes are espe cially promising at LHC energies where heavy quarks (both c and b) are copiously produced. The ALICE detector shall measure the production of open heavy flavours and heavy quarkonium st ates in both proton-proton and heavy-ion collisions at the LHC. The expected performances of ALICE for heavy flavour physics is discussed based on the results of simulation studies on a s election of benchmark channels

  5. Trace Elements in River Waters

    Science.gov (United States)

    Gaillardet, J.; Viers, J.; Dupré, B.

    2003-12-01

    impact studies require knowledge of the natural background concentrations and knowledge of pollutant behavior. For example, it is generally accepted that rare earth elements (REEs) in waters behave as good analogues for the actinides, whose natural levels are quite low and rarely measured. Water quality investigations have clearly been a stimulus for measurement of toxic heavy metals in order to understand their behavior in natural systems.From a more fundamental point of view, it is crucial to understand the behavior of trace elements in geological processes, in particular during chemical weathering and transport by waters. Trace elements are much more fractionated by weathering and transport processes than major elements, and these fractionations give clues for understanding the nature and intensity of the weathering+transport processes. This has not only applications for weathering studies or for the past mobilization and transport of elements to the ocean (potentially recorded in the sediments), but also for the possibility of better utilization of trace elements in the aqueous environment as an exploration tool.In this chapter, we have tried to review the recent literature on trace elements in rivers, in particular by incorporating the results derived from recent ICP-MS measurements. We have favored a "field approach" by focusing on studies of natural hydrosystems. The basic questions which we want to address are the following: What are the trace element levels in river waters? What controls their abundance in rivers and fractionation in the weathering+transport system? Are trace elements, like major elements in rivers, essentially controlled by source-rock abundances? What do we know about the chemical speciation of trace elements in water? To what extent do colloids and interaction with solids regulate processes of trace elements in river waters? Can we relate the geochemistry of trace elements in aquatic systems to the periodic table? And finally, are we able to

  6. New inline desander technology for challenging sand separation applications

    Energy Technology Data Exchange (ETDEWEB)

    Abdalla, T.; Akdim, M.R.; Fantoft, R. [FMC Technologies. Arnhem (Netherlands). CDS Separation Systems

    2010-07-01

    Sand production is a problematic issue for many oil and gas operators. This paper presented details of a desanding technology designed for heavy crude applications as well as multiphase streams containing gas. the InLine desander application can also be used in sub-sea separation systems. The desander was designed to obtain a high separation efficiency the ability to accept high inlet sand concentrations. The desander was comprised of a fluid flow inlet and an axial swirl element that generates high rotational velocities that drive gravitational forces in a separation chamber. The generated G-forces pushed solids to the outer surfaces and downward to the solids outlet. Separated solids were extracted either as particles to settle into an accumulation vessel, or as a highly concentrated slurry. A secondary liquid was then created in the centre of the desander to moved upward and exited via a vortex finder into a liquid outlet. The technology can also be used for small particles and bulk sand separation technologies. Methods for evaluating the efficiency of sand removal efficiency for different desanders were also presented, and process applications were reviewed. 2 tabs., 9 figs.

  7. Determination of 63Ni and 55Fe in nuclear waste samples using radiochemical separation and liquid scintillation counting

    DEFF Research Database (Denmark)

    Hou, Xiaolin; Frøsig Østergaard, L.; Nielsen, S.P.

    2005-01-01

    An analytical method for the determination of Ni-63 and Fe-55 in nuclear waste samples such as graphite, heavy concrete, aluminium and lead was developed. Different decomposition methods (i.e. ashing, acid digestion and alkali fusion) were investigated for the decomposition of the samples...... and for the separation of Fe and Ni from the matrix. Hydroxide precipitation was used to separate Fe-55 and Ni-63 from the matrix elements and ion exchange chromatography was used to separate Fe-55 and Ni-63 from the interfering radionuclides as well as from each other. The separated Ni-63 was further purified...... by extraction chromatography. The purified Ni-63 and Fe-55 was then measured by liquid scintillation counting. The chemical yields of the separation procedures for Fe-55 and Ni-63 are above 90% and the decontamination factors for all interfering radionuclides are more than 10(5). The detection limits...

  8. HRS Separator

    CERN Multimedia

    2016-01-01

    Footage of the 90 and 60 degree ISOLDE HRS separator magnets in the HRS separator zone. In the two vacuum sectors HRS20 and HRS30 equipment such as the HRS slits SL240, the HRS faraday cup FC300 and wiregrid WG210 can be spotted. Vacuum valves, turbo pumps, beamlines, quadrupoles, water and compressed air connections, DC and signal cabling can be seen throughout the video. The HRS main and user beamgate in the beamline between MAG90 and MAG60 and its switchboxes as well as all vacuum bellows and flanges are shown. Instrumentation such as the HRS scanner unit 482 / 483, the HRS WG470 wiregrid and slits piston can be seen. The different quadrupoles and supports are shown as well as the RILIS guidance tubes and installation at the magnets and the different radiation monitors.

  9. GPS Separator

    CERN Multimedia

    2016-01-01

    Footage of the 70 degree ISOLDE GPS separator magnet MAG70 as well as the switchyard for the Central Mass and GLM (GPS Low Mass) and GHM (GPS High Mass) beamlines in the GPS separator zone. In the GPS20 vacuum sector equipment such as the long GPS scanner 482 / 483 unit, faraday cup FC 490, vacuum valves and wiregrid piston WG210 and WG475 and radiation monitors can also be seen. Also the RILIS laser guidance and trajectory can be seen, the GPS main beamgate switch box and the actual GLM, GHM and Central Beamline beamgates in the beamlines as well as the first electrostatic quadrupoles for the GPS lines. Close up of the GHM deflector plates motor and connections and the inspection glass at the GHM side of the switchyard.

  10. Separation system

    Science.gov (United States)

    Rubin, Leslie S.

    1986-01-01

    A separation system for dewatering radioactive waste materials includes a disposal container, drive structure for receiving the container, and means for releasably attaching the container to the drive structure. Separation structure disposed in the container adjacent the inner surface of the side wall structure retains solids while allowing passage of liquids. Inlet port structure in the container top wall is normally closed by first valve structure that is centrifugally actuated to open the inlet port and discharge port structure at the container periphery receives liquid that passes through the separation structure and is normally closed by second valve structure that is centrifugally actuated to open the discharge ports. The container also includes coupling structure for releasable engagement with the centrifugal drive structure. Centrifugal force produced when the container is driven in rotation by the drive structure opens the valve structures, and radioactive waste material introduced into the container through the open inlet port is dewatered, and the waste is compacted. The ports are automatically closed by the valves when the container drum is not subjected to centrifugal force such that containment effectiveness is enhanced and exposure of personnel to radioactive materials is minimized.

  11. Poisoning of domestic animals with heavy metals

    Directory of Open Access Journals (Sweden)

    Velev Romel

    2009-01-01

    Full Text Available The term heavy metal refers to a metal that has a relatively high density and is toxic for animal and human organism at low concentrations. Heavy metals are natural components of the Earth's crust. They cannot be degraded or destroyed. To a small extent they enter animal organism via food, drinking water and air. Some heavy metals (e.g cooper, iron, chromium, zinc are essential in very low concentrations for the survival of all forms of life. These are described as essential trace elements. However, when they are present in greater quantities, like the heavy metals lead, cadmium and mercury which are already toxic in very low concentrations, they can cause metabolic anomalies or poisoning. Heavy metal poisoning of domestic animals could result, for instance, from drinking-water contamination, high ambient air concentrations near emission sources, or intake via the food chain. Heavy metals are dangerous because they tend to bioaccumulate in a biological organism over time. Manifestation of toxicity of individual heavy metals varies considerably, depending on dose and time of exposure, species, gender and environmental and nutritional factors. Large differences exist between the effects of a single exposure to a high concentration, and chronic exposures to lower doses. The aim of this work is to present the source of poisoning and toxicity of some heavy metals (lead, mercury, cadmium, thallium, arsenic, as well as new data about effects of those heavy metals on the health of domestic animals. .

  12. Process recognition in multi-element soil and stream-sediment geochemical data

    Science.gov (United States)

    Grunsky, E.C.; Drew, L.J.; Sutphin, D.M.

    2009-01-01

    Stream-sediment and soil geochemical data from the Upper and Lower Coastal Plains of South Carolina (USA) were studied to determine relationships between soils and stream sediments. From multi-element associations, characteristic compositions were determined for both media. Primary associations of elements reflect mineralogy, including heavy minerals, carbonates and clays, and the effects of groundwater. The effects of groundwater on element concentrations are more evident in soils than stream sediments. A "winnowing index" was created using ratios of Th to Al that revealed differing erosional and depositional environments. Both soils and stream sediments from the Upper and Lower Coastal Plains show derivation from similar materials and subsequent similar multi-element relationships, but have some distinct differences. In the Lower Coastal Plain, soils have high values of elements concentrated in heavy minerals (Ce, Y, Th) that grade into high values of elements concentrated into finer-grain-size, lower-density materials, primarily comprised of carbonates and feldspar minerals (Mg, Ca, Na, K, Al). These gradational trends in mineralogy and geochemistry are inferred to reflect reworking of materials during marine transgressions and regressions. Upper Coastal Plain stream-sediment geochemistry shows a higher winnowing index relative to soil geochemistry. A comparison of the 4 media (Upper Coastal Plain soils and stream sediments and Lower Coastal Plain soils and stream sediments) shows that Upper Coastal Plain stream sediments have a higher winnowing index and a higher concentration of elements contained within heavy minerals, whereas Lower Coastal Plain stream sediments show a strong correlation between elements typically contained within clays. It is not possible to calculate a functional relationship between stream sediment-soil compositions for all elements due to the complex history of weathering, deposition, reworking and re-deposition. However, depending on

  13. Heavy metal uptake of Geosiphon pyriforme

    Science.gov (United States)

    Scheloske, Stefan; Maetz, Mischa; Schüßler, Arthur

    2001-07-01

    Geosiphon pyriforme represents the only known endosymbiosis between a fungus, belonging to the arbuscular mycorrhizal (AM) fungi, and cyanobacteria (blue-green algae). Therefore we use Geosiphon as a model system for the widespread AM symbiosis and try to answer some basic questions regarding heavy metal uptake or resistance of AM fungi. We present quantitative micro-PIXE measurements of a set of heavy metals (Cu, Cd, Tl, Pb) taken up by Geosiphon-cells. The uptake is studied as a function of the metal concentration in the nutrient solution and of the time Geosiphon spent in the heavy metal enriched medium. The measured heavy metal concentrations range from several ppm to some hundred ppm. Also the influence of the heavy metal uptake on the nutrition transfer of other elements will be discussed.

  14. Heavy ion elastic recoil detection analysis of optoelectronic and semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Dytlewski, N.; Cohen, D.D. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Johnston, P.; Walker, S. [Royal Melbourne Inst. of Tech., VIC (Australia); Whitlow, H.; Hult, M. [Lund Univ. (Sweden); Oestling, M.; Zaring, C. [Royal Inst. of Tech., Stockholm (Sweden)

    1993-12-31

    In recent years, the use of heavy ion time-of-flight elastic recoil spectrometry (HIERDA) has been applied to analyse multi-phase, thin layer devices used in optoelectronics, semiconductors and solar power generation. HIERDA gives simultaneously, mass resolved elemental concentration vs depth profiles of the matrix constituents, and is particularly suited to the determination of light elements in a heavy matrix. The beam/target interaction process is similar to RBS, but has the difference that the recoiling target atoms are detected instead of the scattered projectile. High energy, heavy ions beams bombard the sample, ejecting recoil atoms which are detected at a forward angle of 45 deg. A time-of-flight and total energy detection system enables the ejected particle`s mass to be identified, and allows energy spectra to be obtained and interpreted in an analogous way to RBS, but with the important difference that the elemental spectra are separated, and not superimposed on a background as in RBS. Some of the measurements made with a HIERDA system on the ANTARES Tandem Accelerator at ANSTO are described. 1 refs., 4 figs.

  15. Gas separating

    Science.gov (United States)

    Gollan, A.

    1988-03-29

    Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing. 3 figs.

  16. Flow Separation

    Science.gov (United States)

    1975-11-01

    perfomanoas que oette oirconstance peut entrainer, soit encore, d’un point de vue plus fondamental par la recherche dM phenomknas qui caracterisent 1M...dtfoolleoent, dont le m^canlsme de formation eat en tout point sen- blable h celui qui a etc döcrit § 2.2. XL se caracterise par la presence d’une onde...during orbital maneuvers with the Reaction Control System (RCS) and later plume induced separation leading to aerodynamic heating and control problems

  17. Heavy Metal Stars

    Science.gov (United States)

    2001-08-01

    La Silla Telescope Detects Lots of Lead in Three Distant Binaries Summary Very high abundances of the heavy element Lead have been discovered in three distant stars in the Milky Way Galaxy . This finding strongly supports the long-held view that roughly half of the stable elements heavier than Iron are produced in common stars during a phase towards the end of their life when they burn their Helium - the other half results from supernova explosions. All the Lead contained in each of the three stars weighs about as much as our Moon. The observations show that these "Lead stars" - all members of binary stellar systems - have been more enriched with Lead than with any other chemical element heavier than Iron. This new result is in excellent agreement with predictions by current stellar models about the build-up of heavy elements in stellar interiors. The new observations are reported by a team of Belgian and French astronomers [1] who used the Coude Echelle Spectrometer on the ESO 3.6-m telescope at the La Silla Observatory (Chile). PR Photo 26a/01 : A photo of HD 196944 , one of the "Lead stars". PR Photo 26b/01 : A CES spectrum of HD 196944 . The build-up of heavy elements Astronomers and physicists denote the build-up of heavier elements from lighter ones as " nucleosynthesis ". Only the very lightest elements (Hydrogen, Helium and Lithium [2]) were created at the time of the Big Bang and therefore present in the early universe. All the other heavier elements we now see around us were produced at a later time by nucleosynthesis inside stars. In those "element factories", nuclei of the lighter elements are smashed together whereby they become the nuclei of heavier ones - this process is known as nuclear fusion . In our Sun and similar stars, Hydrogen is being fused into Helium. At some stage, Helium is fused into Carbon, then Oxygen, etc. The fusion process requires positively charged nuclei to move very close to each other before they can unite. But with increasing

  18. Divergent biology of facultative heavy metal plants.

    Science.gov (United States)

    Bothe, Hermann; Słomka, Aneta

    2017-12-01

    literature favours the idea that hyperaccumulation of heavy metals serves plants as deterrent against attack by feeding animals (termed elemental defense hypothesis). The capability to hyperaccumulate heavy metals in A. halleri and N. caerulescens is achieved by duplications and alterations of the cis-regulatory properties of genes coding for heavy metal transporting/excreting proteins. Several metallophytes have developed ecotypes with a varying content of such heavy metal transporters as an adaption to the specific toxicity of a heavy metal site. Copyright © 2017 Elsevier GmbH. All rights reserved.

  19. Production and properties of transuranium elements

    Energy Technology Data Exchange (ETDEWEB)

    Nagame, Y.; Hirata, M. [Japan Atomic Energy Agency, Tokai, Ibaraki (Japan)

    2011-07-01

    We summarize historical perspective of the transuranium elements, neptunium (Np) through lawrencium (Lr), and recent progress on production, and nuclear and chemical properties of these elements. Exotic decay properties of heavy nuclei are also introduced. Chemical properties of transuranium elements in aqueous and solid states are summarized based on the actinide concept. (orig.)

  20. Time-of-flight detector for heavy ion backscattering spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, J.A.; Banks, J.C.; Doyle, B.L. [Sandia National Labs., Albuquerque, NM (United States). Ion Solid Interactions and Defect Physics Dept.

    1994-04-01

    This report describes the results of a two-year laboratory directed research and development project to explore advanced concepts in Heavy Ion Backscattering Spectrometry (HIBS), undertaken with the goal of extending the sensitivity of this relatively new technique to levels unattainable by any other existing trace element surface analysis. Improvements in sensitivity are required for the application of HIBS to contamination control in the microelectronics industry. Tools with sensitivity approaching 10{sup 8} atoms/cm{sup 2} are expected to be essential for enabling advanced IC production by the year 2000. During the project the authors developed a new analysis chamber with channeling goniometer and a prototype time-of-flight detector with a demonstrated sensitivity of {approximately} 5 {times} 10{sup 8} atoms/cm{sup 2} for Au on Si and {approximately} 5 {times} 10{sup 10} for Fe, and sufficient mass resolution to separate contributions from Fe and Cu.

  1. A heavy load for heavy ions

    CERN Multimedia

    2003-01-01

    On 25 September, the two large coils for the dipole magnet of ALICE, the LHC experiment dedicated to heavy ions, arrived at Point 2 on two heavy load trucks after a 1200 km journey from their assembly in Vannes, France.

  2. 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.

  3. Heavy Menstrual Bleeding

    Science.gov (United States)

    ... can cause heavy bleeding. • Medications—Blood thinners and aspirin can cause heavy menstrual bleeding. The copper intrauterine ... on the ovaries, fallopian tubes, and other pelvic structures. Endometrium: The lining of the uterus. Fibroids: Growths, ...

  4. Analysis of spatial autocorrelation patterns of heavy and super-heavy rainfall in Iran

    Science.gov (United States)

    Rousta, Iman; Doostkamian, Mehdi; Haghighi, Esmaeil; Ghafarian Malamiri, Hamid Reza; Yarahmadi, Parvane

    2017-09-01

    Rainfall is a highly variable climatic element, and rainfall-related changes occur in spatial and temporal dimensions within a regional climate. The purpose of this study is to investigate the spatial autocorrelation changes of Iran's heavy and super-heavy rainfall over the past 40 years. For this purpose, the daily rainfall data of 664 meteorological stations between 1971 and 2011 are used. To analyze the changes in rainfall within a decade, geostatistical techniques like spatial autocorrelation analysis of hot spots, based on the Getis-Ord G i statistic, are employed. Furthermore, programming features in MATLAB, Surfer, and GIS are used. The results indicate that the Caspian coast, the northwest and west of the western foothills of the Zagros Mountains of Iran, the inner regions of Iran, and southern parts of Southeast and Northeast Iran, have the highest likelihood of heavy and super-heavy rainfall. The spatial pattern of heavy rainfall shows that, despite its oscillation in different periods, the maximum positive spatial autocorrelation pattern of heavy rainfall includes areas of the west, northwest and west coast of the Caspian Sea. On the other hand, a negative spatial autocorrelation pattern of heavy rainfall is observed in central Iran and parts of the east, particularly in Zabul. Finally, it is found that patterns of super-heavy rainfall are similar to those of heavy rainfall.

  5. A Heavy Metal Atmospheric Deposition Study in the South Ural Mountains

    CERN Document Server

    Frontasyeva, M V; Steinnes, E; Lyapunov, S M; Cherchintsev, V D

    2002-01-01

    Samples of the mosses Hylocomium splendens and Pleurozium schreberi, collected in the summer of 1998, were used to study the atmospheric deposition of heavy metals and other toxic elements in the Chelyabinsk Region situated in the South Ural, one of the most heavily polluted industrial areas of the Russian Federation. Samples of natural soils were collected simultaneously with moss at the same 30 sites in order to investigate surface accumulation of heavy metals and to examine the correlation of elements in moss and soil samples in order to separate contributions from atmospheric deposition and from soil minerals. A total of 38 elements (Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Rb, Sr, Zr, Mo, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Hf, Ta, W, Au, Th, U) in soil and 33 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Ag, Sb, Cs, Ba, La, Ce, Sm, Tb, Yb, Hf, Ta, W, Au, Th, U) in mosses were determined by epithermal neutron activation analysis. The elem...

  6. Superheavy element chemistry at GARIS

    Directory of Open Access Journals (Sweden)

    Haba Hiromitsu

    2016-01-01

    Full Text Available A gas-jet transport system has been installed to the RIKEN GAs-filled Recoil Ion Separator, GARIS to start up SuperHeavy Element (SHE chemistry. This system is a promising approach for exploring new frontiers in SHE chemistry: background radioactivities from unwanted by-products are suppressed, a high gas-jet transport yield is achieved, and new chemical reactions can be investigated. Useful radioisotopes of 261Rfa,b, 262Db, and 265Sga,b for chemical studies were produced in the reactions of 248Cm(18O,5n261Rfa,b, 248Cm(19F,5n262Db, and 248Cm(22Ne,5n265Sga,b, respectively. They were successfully extracted to a chemistry laboratory by the gas-jet method. Production and decay properties of 261Rfa,b, 262Db, and 265Sga,b were investigated in detail with the rotating wheel apparatus for α- and spontaneous fission spectrometry. Present status and perspectives of the SHE chemistry at GARIS are also briefly presented.

  7. From heavy nuclei to super-heavy nuclei; Des noyaux lourds aux super-lourds

    Energy Technology Data Exchange (ETDEWEB)

    Theisen, Ch

    2003-01-01

    The existence of super-heavy nuclei has been predicted nearly fifty years ago. Due to the strong coulomb repulsion, the stabilisation of these nuclei is possible only through shell effects. The reasons for this fragile stability, as well as the theoretical predictions concerning the position of the island of stability are presented in the first part of this lecture. In the second part, experiments and experimental techniques which have been used to synthesize or search for super-heavy elements are described. Spectroscopic studies performed in very heavy elements are presented in the following section. We close this lecture with techniques that are currently being developed in order to reach the superheavy island and to study the structure of very-heavy nuclei. (author)

  8. Effects of Heavy Metal Toxicity on Human Health

    OpenAIRE

    Guluzar Ozbolat; Abdullah Tuli

    2016-01-01

    Heavy metals are the elements that can be toxic even at low concentrations. It is often used as a group name for metals and semimetals (metalloids) that have been associated with contamination and potential toxicity or ecotoxicity. Heavy metals are toxic to human health. Because it cannot be discarded with (kidney, liver intestine, skin, lung) without special support from most of the body's normal excretion routes Therefore, a large part of the heavy metals accumulate in biological organisms...

  9. Two new separation schemes for the group isolation of rare earth elements (REE) from biological and other matrices and their determination by ICP-MS, NAA and chromatographic methods

    National Research Council Canada - National Science Library

    Rajmund S. Dybczyński; Zbigniew Samczyński; Iwona Bartosiewicz; Krzysztof Kulisa; Halina Polkowska-Motrenko; Marta Pyszynska; Iga Zuba

    2017-01-01

    ...) from accompanying elements, were devised. After checking their performance with the aid of radioactive tracers, the schemes were further used together with ICP-MS, NAA and ion exchange chromatography for the determination of Sc, Y, La, Ce...

  10. Study on the behavior of heavy metals during thermal treatment of municipal solid waste (MSW) components.

    Science.gov (United States)

    Yu, Jie; Sun, Lushi; Wang, Ben; Qiao, Yu; Xiang, Jun; Hu, Song; Yao, Hong

    2016-01-01

    Laboratory experiments were conducted to investigate the volatilization behavior of heavy metals during pyrolysis and combustion of municipal solid waste (MSW) components at different heating rates and temperatures. The waste fractions comprised waste paper (Paper), disposable chopstick (DC), garbage bag (GB), PVC plastic (PVC), and waste tire (Tire). Generally, the release trend of heavy metals from all MSW fractions in rapid-heating combustion was superior to that in low-heating combustion. Due to the different characteristics of MSW fractions, the behavior of heavy metals varied. Cd exhibited higher volatility than the rest of heavy metals. For Paper, DC, and PVC, the vaporization of Cd can reach as high as 75% at 500 °C in the rapid-heating combustion due to violent combustion, whereas a gradual increase was observed for Tire and GB. Zn and Pb showed a moderate volatilization in rapid-heating combustion, but their volatilities were depressed in slow-heating combustion. During thermal treatment, the additives such as kaolin and calcium can react or adsorb Pb and Zn forming stable metal compounds, thus decreasing their volatilities. The formation of stable compounds can be strengthened in slow-heating combustion. The volatility of Cu was comparatively low in both high and slow-heating combustion partially due to the existence of Al, Si, or Fe in residuals. Generally, in the reducing atmosphere, the volatility of Cd, Pb, and Zn was accelerated for Paper, DC, GB, and Tire due to the formation of elemental metal vapor. TG analysis also showed the reduction of metal oxides by chars forming elemental metal vapor. Cu2S was the dominant Cu species in reducing atmosphere below 900 °C, which was responsible for the low volatility of Cu. The addition of PVC in wastes may enhance the release of heavy metals, while GB and Tire may play an opposite effect. In controlling heavy metal emission, aluminosilicate- and calcium-based sorbents can be co-treated with fuels. Moreover

  11. Heavy Quarks, QCD, and Effective Field Theory

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Mehen

    2012-10-09

    The research supported by this OJI award is in the area of heavy quark and quarkonium production, especially the application Soft-Collinear E ective Theory (SCET) to the hadronic production of quarkonia. SCET is an e ffective theory which allows one to derive factorization theorems and perform all order resummations for QCD processes. Factorization theorems allow one to separate the various scales entering a QCD process, and in particular, separate perturbative scales from nonperturbative scales. The perturbative physics can then be calculated using QCD perturbation theory. Universal functions with precise fi eld theoretic de nitions describe the nonperturbative physics. In addition, higher order perturbative QCD corrections that are enhanced by large logarithms can be resummed using the renormalization group equations of SCET. The applies SCET to the physics of heavy quarks, heavy quarkonium, and similar particles.

  12. Characterization of Heavy Metals in Vegetables Using Inductive ...

    African Journals Online (AJOL)

    The heavy metals or trace elements play an important role in the metabolic pathways during the growth and development of plants, when available in required concentration. The heavy metal concentration of. Cadmium (Cd), Cobalt (Co), Copper (Cu), Iron (Fe), Nickel (Ni), Lead (Pb) and Zinc (Zn) was analyzed using ...

  13. urban dietary heavy metal intake from protein foods and vegetables

    African Journals Online (AJOL)

    Mgina

    ABSTRACT. Contamination of food and food products by heavy metals has made dietary intake as one of the major routes of these harmful elements to human beings. The human dietary intake of heavy metals cadmium, copper, lead and zinc from protein-foods (beans, meat, fish, milk) and green vegetables consumed daily ...

  14. Urban Dietary Heavy Metal Intake from Protein Foods and ...

    African Journals Online (AJOL)

    Contamination of food and food products by heavy metals has made dietary intake as one of the major routes of these harmful elements to human beings. The human dietary intake of heavy metals cadmium, copper, lead and zinc from protein-foods (beans, meat, fish, milk) and green vegetables consumed daily from ...

  15. Assessment of physicochemical qualities, heavy metal ...

    African Journals Online (AJOL)

    Ogbe

    2012-08-23

    Aug 23, 2012 ... Key words: Aquatic biota, contamination, pollution, public health, microbial indicators, toxic effects. INTRODUCTION. Water is ... commonly occur in water and wastewater can be divided into four separate groups. ... heavy/toxic metal contamination of the Shanomi creek of the Warri river, hence the need for ...

  16. Nutritional Composition, Vitamins, Minerals And Toxic Heavy

    African Journals Online (AJOL)

    TONUKARI

    This study aimed at analyzing the nutritional potential of a wild edible plant, Trianthema portulacastrum. L. widely used in Peshawar, Khyber Pakhtunkhwa, Pakistan. The nutritional composition, vitamins, minerals and heavy elements were analyzed following the standard methods of Association of Official. Analytical ...

  17. PHENIX Results on Heavy-Flavor Yields at Forward Rapidity

    Science.gov (United States)

    Brooks, M.

    2016-12-01

    The PHENIX collaboration is actively pursuing a physics program to make precision open and closed heavy flavor measurements over a large rapidity range (- 2.2 production at all rapidities and are expanding our measurements of inclusive open heavy flavor to separated charm and beauty measurements carried out via single lepton measurements and through the separation of prompt and B → J / ψ + X production. We present the current status of these measurements.

  18. Scarcity of rare earth elements

    NARCIS (Netherlands)

    de Boer, M.A.; Lammertsma, K.

    2013-01-01

    Rare earth elements (REEs) are important for green and a large variety of high-tech technologies and are, therefore, in high demand. As a result, supply with REEs is likely to be disrupted (the degree of depends on the REE) in the near future. The 17 REEs are divided into heavy and light REEs. Other

  19. Dual magnetic separator for TRI mu P

    NARCIS (Netherlands)

    Berg, G. P. A.; Dermois, O. C.; Dammalapati, U.; Dendooven, Peter; Harakeh, M.N.; Jungmann, K.; Onderwater, C. J. G.; Rogachevskiy, A.; Sohani, M.; Traykov, E.; Willmann, L.; Wilschut, H. W.

    2006-01-01

    The TRI mu P facility, under construction at KVI, requires the production and separation of short-lived and rare isotopes. Direct reactions, fragmentation and fusion-evaporation reactions in normal and inverse kinematics are foreseen to produce nuclides of interest with a variety of heavy-ion beams

  20. HEAVY WATER MODERATED NEUTRONIC REACTOR

    Science.gov (United States)

    Szilard, L.

    1958-04-29

    A nuclear reactor of the type which utilizes uranium fuel elements and a liquid coolant is described. The fuel elements are in the form of elongated tubes and are disposed within outer tubes extending through a tank containing heavy water, which acts as a moderator. The ends of the fuel tubes are connected by inlet and discharge headers, and liquid bismuth is circulated between the headers and through the fuel tubes for cooling. Helium is circulated through the annular space between the outer tubes in the tank and the fuel tubes to cool the water moderator to prevent boiling. The fuel tubes are covered with a steel lining, and suitable control means, heat exchange means, and pumping means for the coolants are provided to complete the reactor assembly.

  1. Toxic Elements

    DEFF Research Database (Denmark)

    Hajeb, Parvaneh; Shakibazadeh, Shahram; Sloth, Jens Jørgen

    2016-01-01

    Food is considered the main source of toxic element (arsenic, cadmium, lead, and mercury) exposure to humans, and they can cause major public health effects. In this chapter, we discuss the most important sources for toxic element in food and the foodstuffs which are significant contributors...... to human exposure. The occurrence of each element in food classes from different regions is presented. Some of the current toxicological risk assessments on toxic elements, the human health effect of each toxic element, and their contents in the food legislations are presented. An overview of analytical...... techniques and challenges for determination of toxic elements in food is also given....

  2. Heavy quark masses

    Science.gov (United States)

    Testa, Massimo

    1990-01-01

    In the large quark mass limit, an argument which identifies the mass of the heavy-light pseudoscalar or scalar bound state with the renormalized mass of the heavy quark is given. The following equation is discussed: m(sub Q) = m(sub B), where m(sub Q) and m(sub B) are respectively the mass of the heavy quark and the mass of the pseudoscalar bound state.

  3. Magnetic mineralogy of heavy metals-contaminated soils

    Science.gov (United States)

    Shenggao, L.

    2012-04-01

    Soils around mine and in urban areas are often contaminated by heavy metals derived from industrial and human activities [1, 2]. These contaminated soils are often characterized by a magnetic enhancement on topsoils. Many studies demonstrated that there are significant correlations between heavy metals and various magnetic parameters in contaminated soils, indicating a strong affinity of heavy metals to magnetic minerals. The magnetic particles in contaminated soils were separated by a magnetic separation technique. The rock magnetism, XRD, field emission scanning electron microscopy equiped with an energy-dispersive X-ray analyzer (FESEM/EDX) were used to characterize their magnetic mineralogy. Results of XRD analysis indicated that the magnetic particles separated from heavy metal-contaminated soils are composed of quartz, magnetite, and hematite. Based on the X-ray diffraction peak intensity, the Fe3O4 was identified as the predominant magnetic mineral phase. The high-temperature magnetization (Ms-T) curves of magnetic particles extracted from contaminated soils show a sharp Ms decrease at about 580C (the Curie temperature of magnetite), suggesting that magnetite is the dominant magnetic carrier. The hysteresis loops of contaminated soils are closed at about 100-200 mT which is consistent with the presence of a dominant ferrimagnetic mineral phase. The FESEM analysis showed a great variety of shapes of magnetic particles in contaminated soils. The most common morphology are observed in the form of spherules, with the sizes ranging from 20 to 100 um. The chemical composition of magnetic particles consist mainly of Fe, Si, Al, and Ca with minor heavy metal elements (Cu, Zn, Hg, and Cr). The semi-quantitative Fe content identified by FESEM/EDX ranged from 40 to 90%. Combined studies of rock magnetism, XRD, and FESEM/EDX indicated that magnetic mineral phases responsible for the magnetic enhancement of contaminated soils are anthropogenic origin which are coarse

  4. Production of heavy water

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, Larry S.; Brown, Sam W.; Phillips, Michael R.

    2017-06-06

    Disclosed are methods and apparatuses for producing heavy water. In one embodiment, a catalyst is treated with high purity air or a mixture of gaseous nitrogen and oxygen with gaseous deuterium all together flowing over the catalyst to produce the heavy water. In an alternate embodiment, the deuterium is combusted to form the heavy water. In an alternate embodiment, gaseous deuterium and gaseous oxygen is flowed into a fuel cell to produce the heavy water. In various embodiments, the deuterium may be produced by a thermal decomposition and distillation process that involves heating solid lithium deuteride to form liquid lithium deuteride and then extracting the gaseous deuterium from the liquid lithium deuteride.

  5. 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.

  6. Wet separation processes as method to separate limestone and oil shale

    Science.gov (United States)

    Nurme, Martin; Karu, Veiko

    2015-04-01

    Biggest oil shale industry is located in Estonia. Oil shale usage is mainly for electricity generation, shale oil generation and cement production. All these processes need certain quality oil shale. Oil shale seam have interlayer limestone layers. To use oil shale in production, it is needed to separate oil shale and limestone. A key challenge is find separation process when we can get the best quality for all product types. In oil shale separation typically has been used heavy media separation process. There are tested also different types of separation processes before: wet separation, pneumatic separation. Now oil shale industry moves more to oil production and this needs innovation methods for separation to ensure fuel quality and the changes in quality. The pilot unit test with Allmineral ALLJIG have pointed out that the suitable new innovation way for oil shale separation can be wet separation with gravity, where material by pulsating water forming layers of grains according to their density and subsequently separates the heavy material (limestone) from the stratified material (oil shale)bed. Main aim of this research is to find the suitable separation process for oil shale, that the products have highest quality. The expected results can be used also for developing separation processes for phosphorite rock or all others, where traditional separation processes doesn't work property. This research is part of the study Sustainable and environmentally acceptable Oil shale mining No. 3.2.0501.11-0025 http://mi.ttu.ee/etp and the project B36 Extraction and processing of rock with selective methods - http://mi.ttu.ee/separation; http://mi.ttu.ee/miningwaste/

  7. Prospects for parity-nonconservation experiments with highly charged heavy ions

    OpenAIRE

    Maul, Martin; Schäfer, Andreas; Greiner, Walter; Indelicato, Paul

    2006-01-01

    We discuss the prospects for parity-nonconservation experiments with highly charged heavy ions. Energy levels and parity mixing for heavy ions with 2–5 electrons are calculated. We investigate two-photon transitions and the possibility of observing interference effects between weak-matrix elements and Stark matrix elements for periodic electric field configurations.

  8. Prospects for Parity Non-conservation Experiments with Highly Charged Heavy Ions

    OpenAIRE

    Maul, M.; Schäfer, A.; Greiner, W.; Indelicato, P.

    1996-01-01

    We discuss the prospects for parity non-conservation experiments with highly charged heavy ions. Energy levels and parity mixing for heavy ions with two to five electrons are calculated. We investigate two-photon-transitions and the possibility to observe interference effects between weak-matrix elements and Stark matrix elements for periodic electric field configurations.

  9. New neutron-deficient isotopes of barium and rare-earth elements

    CERN Document Server

    Bogdanov, D D; Karnaukhov, V A; Petrov, L A; Plochocki, A; Subbotin, V G; Voboril, J

    1976-01-01

    The authors present an investigation of the short-lived neutron- deficient isotopes of barium and rare-earth elements. By using the BEMS-2 isotope separator on a heavy ion beam, 19 new isotopes were produced with mass numbers ranging from 117 to 138. Five of these (/sup 117/Ba, /sup 129,131/Nd and /sup 133,135/Sm) turned out to be delayed proton emitters. The beta -decay probabilities for the new isotopes have been analyzed in terms of the beta -strength function. An analysis of the proton spectrum shape has been performed using the statistical model for delayed proton emission.

  10. Trace metals in heavy crude oils and tar sand bitumens

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, J.G.

    1990-11-28

    Fe, Ni, and V are considered trace impurities in heavy crude oils and tar sand bitumens. In order to understand the importance of these metals, we have examined several properties: (1) bulk metals levels, (2) distribution in separated fractions, (3) size behavior in feeds and during processing, (4) speciation as a function of size, and (5) correlations with rheological properties. Some of the results of these studies show: (1) V and Ni have roughly bimodal size distributions, (2) groupings were seen based on location, size distribution, and Ni/V ratio of the sample, (3) Fe profiles are distinctively different, having a unimodal distribution with a maximum at relatively large molecular size, (4) Fe concentrations in the tar sand bitumens suggest possible fines solubilization in some cases, (5) SARA separated fractions show possible correlations of metals with asphaltene properties suggesting secondary and tertiary structure interactions, and (6) ICP-MS examination for soluble ultra-trace metal impurities show the possibility of unexpected elements such as U, Th, Mo, and others at concentrations in the ppB to ppM range. 39 refs., 13 figs., 5 tabs.

  11. Multivariant statistical methods to examine trace element distribution in Ruhr coals; Multivariate statistische Methoden zur Untersuchung der Spurenelementverteilung in Ruhrgebietskohlen

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, R.; Hagemann, H.W.; Wolf, M. [RWTH Aachen (Germany). Lehrstuhl fuer Geologie, Geochemie und Lagerstaetten; Wolff-Fischer, E.

    1996-12-01

    Multivariant statistical analyses were used to examine the bonding of coal-relevant trace elements As, Be, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, U, V and Zn with the minerals in 31 types of coal in the Ruhr coalfield. Samples chosen came from Westfal A to Westfal C. The trace element analyses and radioscopic phase analyses to establish the mineral content were carried out on both low and high-ash outputs from a laboratory flotation. Using factor analysis the geochemical character of the trace elements was described and `clay-mineral`, `sulphide` and, `heavy crop mineral` factors deduced. Cluster analysis in the Q-mode yields a separation according to the stratigraphy, while the R-mode provides an agglomeration according to the geochemical character of the trace elements. (orig.)

  12. Separation mechanisms in a plasma centrifuge

    Energy Technology Data Exchange (ETDEWEB)

    Timchenko, N.N.; Khripunov, B.I.

    1979-01-01

    The separation of elements and isotopes is studied in a fully ionized plasma with crossed E and H fields. Two separation mechanisms, the centrifuge mechanism and polarization, are discussed. The parameter ranges in which each of these mechanisms is important are found. The mechanisms are compared in terms of relative efficiency.

  13. Recovery of palladium, cesium, and selenium from heavy metal alkali borosilicate glass by combination of heat treatment and leaching processes

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhanglian; Okada, Takashi, E-mail: t-okada@u-fukui.ac.jp; Nishimura, Fumihiro; Yonezawa, Susumu

    2017-06-05

    Highlights: • A separation technique of both noble and less noble metal from glass is studied. • Via reductive heat treatment, 80% of palladium is extracted in liquid bismuth. • Sodium–potassium-rich materials with cesium and selenium are phase separated. • From the materials, over 80% of cesium and selenium are extracted in water. - Abstract: Reductive heat-treatment and leaching process were applied to a simulated lead or bismuth soda-potash-borosilicate glass with palladium, cesium, and selenium to separate these elements. In the reductive heat treatment, palladium is extracted in liquid heavy metal phase generated by the reduction of the heavy metal oxides, whereas cesium and selenium are concentrated in phase separated Na–K-rich materials on the glass surface. From the materials, cesium and selenium can be extracted in water, and the selenium extraction was higher in the treatment of the bismuth containing glass. The chemical forms of palladium in the glass affected the extraction efficiencies of cesium and selenium. Among the examined conditions, in the bismuth glass treatment, the cesium and selenium extraction efficiencies in water were over 80%, and that of palladium in liquid bismuth was over 80%.

  14. First dedicated in-beam X-ray measurement in heavy-ion fusion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Berner, C. [Technische Universitaet Muenchen, Lehrstuhl E12 (Germany); RIKEN, Research Group for Superheavy Elements (Japan); Henning, W. [Argonne National Laboratory, Physics Division (United States); RIKEN, Research Group for Superheavy Elements (Japan); Muecher, D.; Gernhaeuser, R.; Hellgartner, S.; Maier, L. [Technische Universitaet Muenchen, Lehrstuhl E12 (Germany); Morita, K.; Morimoto, K.; Kaji, D.; Wakabayashi, Y.; Baba, H. [RIKEN, Research Group for Superheavy Elements (Japan); Lutter, R. [Ludwig-Maximilians-Universitaet, Muenchen (Germany)

    2016-07-01

    We report on an experiment aiming at in-beam X-ray spectroscopy of heavy and superheavy elements (SHE). The goal is to establish K-X-ray spectroscopy as a sensitive tool to identify SHE produced in fusion reactions. SHE, formed after cold or hot fusion, are usually identified via the alpha-decay products, which have to be connected to well-known elements. However, various theories predict spontaneous fission as the dominant decay mode for the daughter nuclides. Additionally, half-lives of these elements are expected to increase to values impeding the identification of SHE solely by their decay. The in-beam identification of the characteristic X-rays would precisely allow to identify the charge number of the produced SHE. Experiments were performed at the RIKEN Nishina Centre for Accelerator based Science by using the gas-filled magnet separator GARIS for superheavy element detection. A high-purity, low-energy planar germanium LEGe-detector was adapted to the GARIS system at the target place for the first time in order to measure the element-characteristic, prompt X-ray emission.

  15. Testing applicability of black poplar (Populus nigra L.) bark to heavy metal air pollution monitoring in urban and industrial regions.

    Science.gov (United States)

    Berlizov, A N; Blum, O B; Filby, R H; Malyuk, I A; Tryshyn, V V

    2007-01-01

    A comparative study of the capabilities of black poplar-tree (Populus nigra L.) bark as a biomonitor of atmospheric heavy-metal pollution is reported. Performance indicators (concentrations and enrichment factors) of heavy metal bioaccumulation of bark were compared to the corresponding indicators of epiphytic lichens Xanthoria parietina (L.) Th. Fr. and Physcia adscendens (Fr.) H. Oliver, collected simultaneously with bark samples within the Kiev urban-industrial conurbation. The concentrations of 40 minor and trace elements in the samples were measured by a combination of epithermal and instrumental neutron activation analysis (NAA) using a 10 MW nuclear research reactor WWR-M as the neutron source. Statistical analysis of the data was carried out using non-parametric tests. It was shown that for the majority of the elements determined a good correlation exists between their concentrations in bark and in the lichen species. The accumulation capability of the bark was found to be as effective as, and in some cases better, for both types of lichens. Based on the background levels and variations of the elemental concentration in black poplar-tree bark, threshold values for the enrichment factors were established. For a number of elements (As, Au, Ce, Co, Cr, Cu, La, Mn, Mo, Ni, Sb, Sm, Ti, Th, U, V, W) an interspecies calibration was performed. An optimized pre-irradiation treatment of the bark sample was employed which efficiently separated the most informative external layer from the deeper layers of the bark and thus minimized variations of the element concentrations. Results of this study support black poplar-tree bark as an alternative to epiphytic lichens for heavy metal air pollution monitoring in urban and industrial regions, where severe environmental conditions may result in scarcity or even lack of the indicator species.

  16. 40 CFR 86.079-31 - Separate certification.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Separate certification. 86.079-31... Petroleum Gas-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.079-31 Separate certification. Where possible a manufacturer should include in a single application for certification all vehicles (or engines...

  17. Chemistry of the superheavy elements.

    Science.gov (United States)

    Schädel, Matthias

    2015-03-13

    The quest for superheavy elements (SHEs) is driven by the desire to find and explore one of the extreme limits of existence of matter. These elements exist solely due to their nuclear shell stabilization. All 15 presently 'known' SHEs (11 are officially 'discovered' and named) up to element 118 are short-lived and are man-made atom-at-a-time in heavy ion induced nuclear reactions. They are identical to the transactinide elements located in the seventh period of the periodic table beginning with rutherfordium (element 104), dubnium (element 105) and seaborgium (element 106) in groups 4, 5 and 6, respectively. Their chemical properties are often surprising and unexpected from simple extrapolations. After hassium (element 108), chemistry has now reached copernicium (element 112) and flerovium (element 114). For the later ones, the focus is on questions of their metallic or possibly noble gas-like character originating from interplay of most pronounced relativistic effects and electron-shell effects. SHEs provide unique opportunities to get insights into the influence of strong relativistic effects on the atomic electrons and to probe 'relativistically' influenced chemical properties and the architecture of the periodic table at its farthest reach. In addition, they establish a test bench to challenge the validity and predictive power of modern fully relativistic quantum chemical models. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  18. Nuclear structure effects in quasifission – understanding the formation of the heaviest elements

    Directory of Open Access Journals (Sweden)

    Hinde D. J.

    2016-01-01

    Full Text Available Quasifission is an important process suppressing the fusion of two heavy nuclei in reactions used to create superheavy elements. Quasifission results in rapid separation of the dinuclear system initially formed at contact. Achieving reliable a priori prediction of quasifission probabilities is a very diffcult problem. Through measurements with projectiles from C to Ni, the Australian National University’s Heavy Ion Accelerator Facility and CUBE spectrometer have been used to map out mass-angle distributions (MAD - the fission mass-ratio as a function of centre-of-mass angle. These provide information on quasifission dynamics in the least modeldependent way. Average quasifission time-scales have been extracted, and compared with TDHF calculations of the collisions, with good agreement being found. With the baseline information from the survey of experimental MAD, strong influences of the nuclear structure of the projectile and target nuclei can be clearly determined.

  19. Influence of phase separator design on the performance of UASB ...

    African Journals Online (AJOL)

    2016-04-02

    Apr 2, 2016 ... effluent virtually free from settleable solids can be discharged. .... in the gas chamber. Additional solid-liquid separation occurs in the settling zone above the separator elements: particles with sufficiently high settling rates will overcome the ... ventional separator and effects the separation of the biogas and.

  20. Comparative study for separation of atmospheric humic-like substance (HULIS) by ENVI-18, HLB, XAD-8 and DEAE sorbents: elemental composition, FT-IR, 1H NMR and off-line thermochemolysis with tetramethylammonium hydroxide (TMAH).

    Science.gov (United States)

    Fan, Xingjun; Song, Jianzhong; Peng, Ping'an

    2013-11-01

    Humic-like substances (HULIS) are significant constituents of aerosols, and the isolation and characterization of HULIS by solid-phase extraction methods are dependent on the sorbents used. In this study, we used the following five methods: ENVI-18, HLB-M, HLB-N, XAD-8 and DEAE, to isolate atmospheric HULIS at an urban site. Then we conducted a comparative investigation of the HULIS chemical characteristics by means of elemental analysis, Fourier transform infrared spectroscopy, (1)H nuclear magnetic resonance spectroscopy and off-line thermochemolysis with tetramethylammonium hydroxide. The results indicate that HULIS isolated using different methods show many similarities in chemical composition and structure. Some differences were however also observed between the five isolated HULIS: HULISHLB-M contains a relatively high content of OCH group, compared to HULISENVI-18 and HULISXAD-8; HULISXAD-8 contains a relatively high content of hydrophobic and aromatic components, compared to HULISENVI-18 and HULISHLB-M; HULISDEAE contains the highest content of aromatic functional groups, as inferred by (1)H NMR spectra, but a great amount of salts generally present in the HULISDEAE and thereby limited the choices for characterizing the materials (i.e., elemental analysis and TMAH thermochemolysis); HULISHLB-N has relatively high levels of H and N, a high N/C atomic ratio, and includes N-containing functional groups, which suggests that it has been altered by 2% ammonia introduced in the eluents. In summary, we found that ENVI-18, HLB-M, and XAD-8 are preferable methods for isolation and characterization of HULIS in atmospheric aerosols. These results also suggest that caution is required when applying DEAE and HLB-N isolating methods for characterizing atmospheric HULIS. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Direct mass measurements of the heaviest elements with Penning traps

    Energy Technology Data Exchange (ETDEWEB)

    Block, M., E-mail: m.block@gsi.de [GSI Helmholtzzentrum für Schwerionenforschung, Planckstrasse 1, 64291 Darmstadt (Germany); Helmholtzinstitut Mainz, 55099 Mainz (Germany); Johannes Gutenberg-Universität, Institut für Kernchemie, 55099 Mainz (Germany)

    2015-12-15

    Penning-trap mass spectrometry (PTMS) is a mature technique to provide atomic masses with highest precision. Applied to radionuclides it enables us to investigate their nuclear structure via binding energies and derived quantities such as nucleon separation energies. Recent progress in slowing down radioactive ion beams in buffer gas cells in combination with advanced ion-manipulation techniques has opened the door to access even the elements above fermium by PTMS. Such elements are produced in complete fusion–evaporation reactions of heavy ions with lead, bismuth, and actinide targets at very low rates. Pioneering high-precision mass measurements of nobelium and lawrencium isotopes have been performed with SHIPTRAP at the GSI Darmstadt, Germany. These have illustrated that direct mass measurements provide reliable anchor points to pin down decay chains and that they allow mapping nuclear shell effects, the reason for the very existence of the heaviest elements. Thus, accurate masses contribute to our understanding of these exotic nuclei with extreme proton numbers. In this article experimental challenges in mass measurements of the heaviest elements with Penning traps are discussed. Some illustrative examples of the nuclear structure features displayed based on the presently known masses are given.

  2. Rare earth element abundances in rocks and minerals from the Fiskenaesset Complex, West Greenland. [comparison with lunar anorthosites

    Science.gov (United States)

    Henderson, P.; Fishlock, S. J.; Laul, J. C.; Cooper, T. D.; Conard, R. L.; Boynton, W. V.; Schmitt, R. A.

    1976-01-01

    The paper reports activation-analysis determinations of rare-earth-element (REE) and other trace-element concentrations in selected rocks, plagioclase, and mafic separates from the Fiskenaesset Complex. The REE abundances are found to be very low and atypical in comparison with other terrestrial anorthosites. The plagioclases are shown to be characterized by a deficiency in heavy RE elements relative to light ones and a positive Eu anomaly, while the mafic separates are enriched in heavy rare earths and have no Eu anomaly, except in one sample. It is found that the bulk and trace-element abundances of the plagioclases are similar to those observed in some lunar anorthosites, but the degree of Eu anomaly is less in the plagioclases. The data are taken as confirmation of the idea that fractionation processes were involved in the origin of the Complex, and it is concluded that the Complex may have been produced from a magma generated by partial melting of a garnet-bearing source.

  3. Crystal structures and thermal decomposition of permanganates AE[MnO{sub 4}]{sub 2} . n H{sub 2}O with the heavy alkaline earth elements (AE=Ca, Sr and Ba)

    Energy Technology Data Exchange (ETDEWEB)

    Henning, Harald; Bauchert, Joerg M.; Conrad, Maurice; Schleid, Thomas [Stuttgart Univ. (Germany). Inst. fuer Anorganische Chemie

    2017-10-01

    Reexamination of the syntheses and crystal structures as well as studies of the thermal decomposition of the heavy alkaline earth metal permanganates Ca[MnO{sub 4}]{sub 2} . 4 H{sub 2}O, Sr[MnO{sub 4}]{sub 2} . 3 H{sub 2}O and Ba[MnO{sub 4}]{sub 2} are the focus of this work. As an alternative to the very inelegant Muthmann method, established for the synthesis of Ba[MnO{sub 4}]{sub 2} a long time ago, we employed a cation-exchange column loaded with Ba{sup 2+} cations and passed through an aqueous potassium-permanganate solution. We later used this alternative also with strontium- and calcium-loaded columns and all the compounds synthesized this way were indistinguishable from the products of the established methods. Ca[MnO{sub 4}]{sub 2} . 4 H{sub 2}O exhibiting [CaO{sub 8}] polyhedra crystallizes in the orthorhombic space group Pccn with the lattice parameters a=1397.15(9), b=554.06(4) and c=1338.97(9) pm with Z=4, whereas Sr[MnO{sub 4}]{sub 2} . 3 H{sub 2}O with [SrO{sub 10}] polyhedra adopts the cubic space group P2{sub 1}3 with a=964.19(7) pm and Z=4. So the harder the AE{sup 2+} cation, the higher its demand for hydration in aqueous solution. Consequently, the crystal structure of Ba[MnO{sub 4}]{sub 2} in the orthorhombic space group Fddd with a=742.36(5), b=1191.23(7) and c=1477.14(9) pm with Z=8 lacks any crystal water, but contains [BaO{sub 12}] polyhedra. During the thermal decomposition of Ca[MnO{sub 4}]{sub 2} . 4 H{sub 2}O, the compound expels up to two water molecules of hydration, before the crystal structure collapses after the loss of the third H{sub 2}O molecule at 157 C. The crystal structure of Sr[MnO{sub 4}]{sub 2} . 3 H{sub 2}O breaks down after the expulsion of the third water molecule as well, but this already occurs at 148 C. For both the calcium and the strontium permanganate samples, orthobixbyite-type α-Mn{sub 2}O{sub 3} and the oxomanganates(III,IV) AEMn{sub 3}O{sub 6} (AE=Ca and Sr) remain as final decomposition products at 800 C

  4. Spectroscopy of very heavy nuclei with a view to study super-heavy nuclei; Spectroscopie de noyaux tres lourds en vue de l'etude des noyaux super-lourds

    Energy Technology Data Exchange (ETDEWEB)

    Khalfallah, F

    2007-08-15

    Within the recent years, the spectroscopic study of single particle orbitals of very heavy elements (VHE) has become possible with the development of increasingly efficient experimental setups. This allows us, through nuclear deformation, to access with these deformed nuclei to orbitals situated around the Fermi level in the spherical superheavy elements (SHE) and learn more about the nuclear structure of these nuclei. The aim of this work is the spectroscopic studies of heavy and very heavy elements. Because of the experimental difficulties associated with the fusion reactions in the VHE region, a detailed optimization studies is essential. Simulation of energy loss and angular straggling of these nuclei due to the interaction in the target and to neutron's evaporation was carried out and allowed us to optimize the angular acceptance of the separators according to the target thickness. An extensive survey and exploration in the VHE region was also conducted on the basis of cross section's systematics in the literature and simulations carried out using the statistical code Hivap. In this framework, the possible extension of the range of validity of a set of Hivap parameters was investigated. This work has enabled us to prepare a list of experiments of interest for the production of very heavy nuclei. In this thesis, our work was concentrated on the spectroscopy of the nuclei No{sup 256} et Rf{sup 256} for which two experimental proposals were accepted. The octupole deformations predicted in the actinides region is studied in another part of this thesis, a part witch is dedicated to the gamma spectroscopy of Pa{sup 223}. The data from a new experiment carried out using the Jurogam-Ritu-Great setup are analysed and compared to previous results. They confirm the octupole deformed shape in this nucleus. (author)

  5. Element specific electronic states and spin-flip-like behavior of Ce in (Ce0.2Gd0.8)Ni composed of heavy fermion CeNi and ferri-magnet GdNi through XMCD method

    Science.gov (United States)

    Yano, K.; Okane, T.; Takeda, Y.; Yamagami, H.; Fujimori, A.; Nishimura, K.; Sato, K.

    2017-06-01

    The electronic states of the three constituent elements in the crystal mixed system between CeNi and GdNi, Ce0.2Gd0.8Ni, were investigated by soft X-ray magnetic circular dichroism (XMCD) with the aid of sum rule analysis. Not only Gd 4f but also Ni 3d and Ce 4f electrons were magnetic and both magnetic moments of Ni and Ce were coupled anti-parallel to the direction of the Gd magnetic moment, which is in accordance with the general rule in rare earth (RE)-transition metal (TM) systems. After saturation, Ce magnetic moment decreased over 2 T and this behavior was explained by a spin-flip behavior of the Ce magnetic moment with keeping their electronic states unchanged. Furthermore, the magnetic field dependence on a part of the XAS at Ce M4,5 absorption edges, which had been observed in the Gd=0.5 disappeared in the present sample in Gd-rich content of 0.8 and this could be explained by the increase of molecular field from Gd on Ce 4f electrons. In addition, sum rule analysis has revealed that the magnetic moments of Gd 4 f and Ni 3d electrons could retain small values of angular (orbital) magnetic moments μL and this was explained consistently.

  6. Renormalons and the heavy quark effective theory

    CERN Document Server

    Martinelli, G; Martinelli, G; Sachrajda, C T

    1995-01-01

    We propose a non-perturbative method for defining the higher dimensional operators which appear in the Heavy Quark Effective Theory (HQET), such that their matrix elements are free of renormalon singularities, and diverge at most logarithmically with the ultra-violet cut-off. Matrix elements of these operators can be computed numerically in lattice simulations of the HQET. We illustrate our procedures by presenting physical definitions of the binding energy (\\lb) and of the kinetic energy (-\\lambda_1/2m_Q) of the heavy quark in a hadron. This allows us to define a ``subtracted pole mass", whose inverse can be used as the expansion parameter in applications of the HQET.

  7. Chemical characterization of element 112.

    Science.gov (United States)

    Eichler, R; Aksenov, N V; Belozerov, A V; Bozhikov, G A; Chepigin, V I; Dmitriev, S N; Dressler, R; Gäggeler, H W; Gorshkov, V A; Haenssler, F; Itkis, M G; Laube, A; Lebedev, V Ya; Malyshev, O N; Oganessian, Yu Ts; Petrushkin, O V; Piguet, D; Rasmussen, P; Shishkin, S V; Shutov, A V; Svirikhin, A I; Tereshatov, E E; Vostokin, G K; Wegrzecki, M; Yeremin, A V

    2007-05-03

    The heaviest elements to have been chemically characterized are seaborgium (element 106), bohrium (element 107) and hassium (element 108). All three behave according to their respective positions in groups 6, 7 and 8 of the periodic table, which arranges elements according to their outermost electrons and hence their chemical properties. However, the chemical characterization results are not trivial: relativistic effects on the electronic structure of the heaviest elements can strongly influence chemical properties. The next heavy element targeted for chemical characterization is element 112; its closed-shell electronic structure with a filled outer s orbital suggests that it may be particularly susceptible to strong deviations from the chemical property trends expected within group 12. Indeed, first experiments concluded that element 112 does not behave like its lighter homologue mercury. However, the production and identification methods used cast doubt on the validity of this result. Here we report a more reliable chemical characterization of element 112, involving the production of two atoms of (283)112 through the alpha decay of the short-lived (287)114 (which itself forms in the nuclear fusion reaction of 48Ca with 242Pu) and the adsorption of the two atoms on a gold surface. By directly comparing the adsorption characteristics of (283)112 to that of mercury and the noble gas radon, we find that element 112 is very volatile and, unlike radon, reveals a metallic interaction with the gold surface. These adsorption characteristics establish element 112 as a typical element of group 12, and its successful production unambiguously establishes the approach to the island of stability of superheavy elements through 48Ca-induced nuclear fusion reactions with actinides.

  8. Pyrolized biochar for heavy metal adsorption

    Science.gov (United States)

    Removal of copper and lead metal ions from water using pyrolized plant materials. Method can be used to develop a low cost point-of-use device for cleaning contaminated water. This dataset is associated with the following publication:DeMessie, B., E. Sahle-Demessie , and G. Sorial. Cleaning Water Contaminated With Heavy Metal Ions Using Pyrolyzed Banana Peel Adsorbents. Separation Science and Technology. Marcel Dekker Incorporated, New York, NY, USA, 50(16): 2448-2457, (2015).

  9. Trace elements determination in high salinity petroleum produced formation water by high-resolution continuum source graphite furnace atomic absorption spectrometry after matrix separation using Chelex-100® resin

    Science.gov (United States)

    Freire, Aline Soares; Santelli, Ricardo Erthal

    2012-05-01

    This study describes a procedure used for the determination of trace metals (Co, Cu, Mn, Ni and Pb) in high salinity petroleum produced formation water (PFW) employing high-resolution continuum source graphite furnace atomic absorption spectrometry for detection and Chelex-100® resin for matrix elimination and analytes preconcentration. Using 15.0 mL of PFW for the separation/preconcentration, detection limits of 0.006, 0.07, 0.03, 0.08 and 0.02 μg L- 1 were obtained for Co, Cu, Mn, Ni and Pb, respectively. The accuracy of the proposed method was evaluated by analyzing three seawater certified reference materials and by recovery tests, and the data indicate that the methodology can be successfully applied to this kind of samples. The precision values, expressed as relative standard deviation (% RSD, n = 10) for 2.0 μg L- 1, were found to be 3.5, 4.0, 9.0, 5.3 and 5.9 for Co, Cu, Mn, Ni and Pb, respectively. The proposed procedure was applied for the determination of these metals in medium and high salinity PFW samples obtained from Brazilian offshore petroleum exploration platforms.

  10. Fictional Separation Logic

    DEFF Research Database (Denmark)

    Jensen, Jonas Buhrkal; Birkedal, Lars

    2012-01-01

    , separation means physical separation. In this paper, we introduce \\emph{fictional separation logic}, which includes more general forms of fictional separating conjunctions P * Q, where "*" does not require physical separation, but may also be used in situations where the memory resources described by P and Q...... overlap. We demonstrate, via a range of examples, how fictional separation logic can be used to reason locally and modularly about mutable abstract data types, possibly implemented using sophisticated sharing. Fictional separation logic is defined on top of standard separation logic, and both the meta...

  11. Separating biological cells

    Science.gov (United States)

    Brooks, D. E.

    1979-01-01

    Technique utilizing electric field to promote biological cell separation from suspending medium in zero gravity increases speed, reduces sedimentation, and improves efficiency of separation in normal gravity.

  12. Heavy Flavour Production

    OpenAIRE

    Nason, P; Ridolfi, G.; Frixione, S.

    1995-01-01

    We review the status of heavy flavour production in QCD. Comparison of experimental and theoretical results for top and bottom production are given. Selected topics in charm production are also discussed.

  13. Atmospheric Heavy Metal Pollution

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 4. Atmospheric Heavy Metal Pollution - Development of Chronological Records and Geochemical Monitoring. Rohit Shrivastav. General Article Volume 6 Issue 4 April 2001 pp 62-68 ...

  14. Heavy Quarks: Summary Report

    CERN Document Server

    Baines, J.; Behnke, O.; Bracinik, J.; Cacciari, M.; Corradi, M.; Dainese, A.; Diglio, S.; Eskola, K.J.; Eynck, T.O.; Geiser, A.; Grindhammer, G.; Jung, H.; Kniehl, B.A.; Kolhinen, V.J.; Kretzer, S.; Kutak, K.; Laenen, Eric; Lagouri, Th.; Lipatov, A.V.; Maltoni, F.; Martin, A.D.; Meyer, A.; Morsch, A.; Motyka, L.; Peters, K.; Petrucci, F.; Piskounova, O.I.; Ranieri, R.; Ruiz, H.; Ryskin, M.G.; Schienbein, I.; Smith, J.; Smizanska, M.; Spiesberger, H.; Tonazzo, A.; Uwer, U.; Verducci, M.; Vogt, R.; Weiser, C.; Zotov, N.P.; Lagouri, Th.

    2006-01-01

    The present status of the heavy-quark production theory is critically reviewed in the first contribution. The second contribution summarises the present heavy flavour data from HERA and gives an outlook of what can be expected from HERA-II. The potential of the LHC experiments for charm and beauty physics is reviewed in the 3rd contribution. Then the relevance of saturation and small-x effects to heavy quark production at HERA and at the LHC are discussed. The non-perturbative aspects of heavy-quark fragmentation and their relevance to HERA and LHC are discussed in the next contribution. Finally, a comparison of different theoretical predictions for HERA and LHC based on different approaches is presented.

  15. Heavy Ion Physics at CMS

    CERN Document Server

    Veres, Gabor

    2017-01-01

    In the present proceedings recent heavy ion results from the Compact Muon Solenoid collaboration at the LHC are presented. These contain comparisons between small and large collision systems, as well as studies of energy evolution, thus include data collected in proton-proton collisions at 13 TeV (2015 and 2016), proton-proton and lead-lead collisions at 5 TeV (2015), and proton-lead collisions at 5 TeV and 8 TeV (2016) center-of-mass energy per nucleon pair. They provide new insights into the properties of the extremely high density and high temperature matter created in heavy ion collisions, while pointing out similarities and differences in comparison to smaller collision systems. These include gluon distribution functions in the lead nucleus; the azimuthal anisotropy of final state particle distributions in all the three different collision systems; charge separation signals from proton-lead collisions and consequences for the Chiral Magnetic Effect; new studies of parton energy loss and its dependence on...

  16. Carrier element-free coprecipitation with 3-phenly-4-o-hydroxybenzylidenamino-4,5-dihydro-1,2,4-triazole-5-one for separation/preconcentration of Cr(III), Fe(III), Pb(II) and Zn(II) from aqueous solutions.

    Science.gov (United States)

    Duran, Celal; Bulut, Volkan N; Gundogdu, Ali; Ozdes, Duygu; Yildirim, Nuri; Soylak, Mustafa; Senturk, H Basri; Elci, Latif

    2009-08-15

    A separation/preconcentration procedure, based on the coprecipitation of Cr(3+), Fe(3+), Pb(2+) and Zn(2+) ions using a new organic coprecipitant, 3-phenly-4-o-hydroxybenzylidenamino-4,5-dihydro-1,2,4-triazole-5-one (POHBAT) without adding any carrier element has been developed. The method, thus, has been called carrier element-free coprecipitation (CEFC). The resultant concentrated elements were determined by flame atomic absorption spectrometric determinations. The influences of some analytical parameters including pH of the solution, amount of the coprecipitant, standing time, centrifugation rate and time, sample volume and diverse ions were investigated on the quantitative recoveries of analyte ions. The validation of the present preconcentration procedure was performed by the analysis of two certified reference materials. The recoveries of understudy analytes were found in the range of 93-98%, while the detection limits were calculated in the range of 0.3-2.0 microg L(-1). The precision of the method evaluated as relative standard deviation (R.S.D.), was in the range of 3-7% depend on the analytes. The proposed method was successfully applied to environmental samples for the determination of the analytes.

  17. Controlling Separation in Turbomachines

    Science.gov (United States)

    Evans, Simon; Himmel, Christoph; Power, Bronwyn; Wakelam, Christian; Xu, Liping; Hynes, Tom; Hodson, Howard

    2010-01-01

    Four examples of flow control: 1) Passive control of LP turbine blades (Laminar separation control). 2) Aspiration of a conventional axial compressor blade (Turbulent separation control). 3) Compressor blade designed for aspiration (Turbulent separation control). 4.Control of intakes in crosswinds (Turbulent separation control).

  18. Molten carbonate fuel cell separator

    Science.gov (United States)

    Nickols, R.C.

    1984-10-17

    In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.

  19. Proceedings of the world heavy oil congress 2011

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    The World Heavy Oil Congress 2011 took place March 2011 in Edmonton, Alberta, Canada. This congress is an international gathering of heavy oil experts and professionals which takes place every 18 months to discuss issues and opportunities facing the heavy oil industry in terms of commercial, technical, regulatory and geo-political areas. Innovative solutions for improving performance, reducing costs and mitigating environmental impacts are presented. Hundreds of presentations were made, courses were delivered, and over 100 companies from 30 countries exhibited. The congress had support from various companies and government entities.This conference featured 133 papers, all of have been catalogued separately for inclusion in this database.

  20. Methods for natural gas and heavy hydrocarbon co-conversion

    Science.gov (United States)

    Kong, Peter C [Idaho Falls, ID; Nelson, Lee O [Idaho Falls, ID; Detering, Brent A [Idaho Falls, ID

    2009-02-24

    A reactor for reactive co-conversion of heavy hydrocarbons and hydrocarbon gases and includes a dielectric barrier discharge plasma cell having a pair of electrodes separated by a dielectric material and passageway therebetween. An inlet is provided for feeding heavy hydrocarbons and other reactive materials to the passageway of the discharge plasma cell, and an outlet is provided for discharging reaction products from the reactor. A packed bed catalyst may optionally be used in the reactor to increase efficiency of conversion. The reactor can be modified to allow use of a variety of light sources for providing ultraviolet light within the discharge plasma cell. Methods for upgrading heavy hydrocarbons are also disclosed.

  1. Heavy metals in human teeth dentine: A bio-indicator of metals exposure and environmental pollution.

    Science.gov (United States)

    Asaduzzaman, Khandoker; Khandaker, Mayeen Uddin; Binti Baharudin, Nurul Atiqah; Amin, Yusoff Bin Mohd; Farook, Mohideen Salihu; Bradley, D A; Mahmoud, Okba

    2017-06-01

    With rapid urbanization and large-scale industrial activities, modern human populations are being increasingly subjected to chronic environmental heavy metal exposures. Elemental uptake in tooth dentine is a bioindicator, the uptake occurring during the formation and mineralization processes, stored to large extent over periods of many years. The uptake includes essential elements, most typically geogenic dietary sources, as well as non-essential elements arising through environmental insults. In this study, with the help of the Dental Faculty of the University of Malaya, a total of 50 separate human teeth were collected from dental patients of various ethnicity, age, gender, occupation, dietary habit, residency, etc. Analysis was conducted using inductively coupled plasma-mass spectrometry (ICP-MS), most samples indicating the presence of the following trace elements, placed in order of concentration, from least to greatest: As, Mn, Ba, Cu, Cr, Pb, Zn, Hg, Sb, Al, Sr, Sn. The concentrations have been observed to increase with age. Among the ethnic groups, the teeth of ethnic Chinese showed marginally greater metal concentrations than those of the Indians and Malays, the teeth dentine of females generally showing greater concentrations than that of males. Greater concentrations of Hg, Cu and Sn were found in molars while Pb, Sr, Sb and Zn were present in greater concentrations in incisors. With the elevated concentration levels of heavy metals in tooth dentine reflecting pollution from industrial emissions and urbanization, it is evident that human tooth dentine can provide chronological information on exposure, representing a reliable bio-indicator of environmental pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Heavy Metal Pollution Around International Hatay Airport

    Directory of Open Access Journals (Sweden)

    Abdullah Özkan

    2017-02-01

    Full Text Available In this study, it was aimed to determine the heavy metal pollution in the agricultural lands around Hatay airport and travel possible alteration in the amount of heavy metal on the land in accordance with the distance to the airport. For this purpose, the airport was chosen as the center and 27 soil samples were obtained around the airport at 2 km intervals in depth ranging from 0 to 30 cm. Lead (Pb, cadmium (Cd, nickel (Ni, chrome (Cr, cobalt (Co, aluminium (Al, iron (Fe, copper (Cu, manganese (Mn and zinc (Zn elements in soil samples were analysed using MP-AES instrument by DTPA method. (3 repetition for each sample. As a result of the analysis, heavy metal concentrations were found as Pb 0-1.45 mg/kg, Cd 0-0.220 mg/kg, Ni 0-3.95 mg/kg, Cr 0-0.780 mg/kg, Co 0-0.270 mg/kg, Al 0-0.700 mg/kg, Fe 1.47- 16.2 mg/kg, Cu 0.400-5.35 mg/kg, Mn 0-19 mg/kg and Zn 0.050-3.14 mg/kg. When comparing the obtained data through this study with allowable concentrations of heavy metals in soil of Environment and Forest Directorates Guidance, it was determined that the heavy metal concentration of the soil does not pose any problems in terms of heavy metal pollution. Besides, iron concentration was decreased when the distance to the airport is increased.

  3. Very heavy dark Skyrmions

    Science.gov (United States)

    Dick, Rainer

    2017-12-01

    A dark sector with a solitonic component provides a means to circumvent the problem of generically low annihilation cross sections of very heavy dark matter particles. At the same time, enhanced annihilation cross sections are necessary for indirect detection of very heavy dark matter components beyond 100 TeV. Non-thermally produced dark matter in this mass range could therefore contribute to the cosmic γ -ray and neutrino flux above 100 TeV, and massive Skyrmions provide an interesting framework for the discussion of these scenarios. Therefore a Higgs portal and a neutrino portal for very heavy Skyrmion dark matter are discussed. The Higgs portal model demonstrates a dark mediator bottleneck, where limitations on particle annihilation cross sections will prevent a signal from the potentially large soliton annihilation cross sections. This problem can be avoided in models where the dark mediator decays. This is illustrated by the neutrino portal for Skyrmion dark matter.

  4. Double-β decay matrix elements from lattice quantum chromodynamics

    Science.gov (United States)

    Tiburzi, Brian C.; Wagman, Michael L.; Winter, Frank; Chang, Emmanuel; Davoudi, Zohreh; Detmold, William; Orginos, Kostas; Savage, Martin J.; Shanahan, Phiala E.; Nplqcd Collaboration

    2017-09-01

    A lattice quantum chromodynamics (LQCD) calculation of the nuclear matrix element relevant to the n n →p p e e ν¯eν¯e transition is described in detail, expanding on the results presented in Ref. [P. E. Shanahan et al., Phys. Rev. Lett. 119, 062003 (2017), 10.1103/PhysRevLett.119.062003]. This matrix element, which involves two insertions of the weak axial current, is an important input for phenomenological determinations of double-β decay rates of nuclei. From this exploratory study, performed using unphysical values of the quark masses, the long-distance deuteron-pole contribution to the matrix element is separated from shorter-distance hadronic contributions. This polarizability, which is only accessible in double-weak processes, cannot be constrained from single-β decay of nuclei, and is found to be smaller than the long-distance contributions in this calculation, but non-negligible. In this work, technical aspects of the LQCD calculations, and of the relevant formalism in the pionless effective field theory, are described. Further calculations of the isotensor axial polarizability, in particular near and at the physical values of the light-quark masses, are required for precise determinations of both two-neutrino and neutrinoless double-β decay rates in heavy nuclei.

  5. Recent heavy flavor measurements from PHENIX at RHIC

    Directory of Open Access Journals (Sweden)

    Hachiya Takashi

    2017-01-01

    Full Text Available Heavy flavor is a useful probe to study the property of the strongly coupled quark gluon plasma created in high-energy heavy-ion collisions. They are produced in the early stage of the collisions, and then propagate though QGP. Therefore, they carry information of QGP. PHENIX measures the separated bottom and charm production using the precise tracking by the silicon vertex detector installed at mid-rapidity and forward rapidity. In this article, we present the recent results of separated charm and bottom modification in Au+Au and Cu+Au collisions, and charmonia production in p+Al and p+Au collisions.

  6. Recent heavy flavor measurements from PHENIX at RHIC

    Science.gov (United States)

    Hachiya, Takashi

    2017-04-01

    Heavy flavor is a useful probe to study the property of the strongly coupled quark gluon plasma created in high-energy heavy-ion collisions. They are produced in the early stage of the collisions, and then propagate though QGP. Therefore, they carry information of QGP. PHENIX measures the separated bottom and charm production using the precise tracking by the silicon vertex detector installed at mid-rapidity and forward rapidity. In this article, we present the recent results of separated charm and bottom modification in Au+Au and Cu+Au collisions, and charmonia production in p+Al and p+Au collisions.

  7. Species sensitivity analysis of heavy metals to freshwater organisms.

    Science.gov (United States)

    Xin, Zheng; Wenchao, Zang; Zhenguang, Yan; Yiguo, Hong; Zhengtao, Liu; Xianliang, Yi; Xiaonan, Wang; Tingting, Liu; Liming, Zhou

    2015-10-01

    Acute toxicity data of six heavy metals [Cu, Hg, Cd, Cr(VI), Pb, Zn] to aquatic organisms were collected and screened. Species sensitivity distributions (SSD) curves of vertebrate and invertebrate were constructed by log-logistic model separately. The comprehensive comparisons of the sensitivities of different trophic species to six typical heavy metals were performed. The results indicated invertebrate taxa to each heavy metal exhibited higher sensitivity than vertebrates. However, with respect to the same taxa species, Cu had the most adverse effect on vertebrate, followed by Hg, Cd, Zn and Cr. When datasets from all species were included, Cu and Hg were still more toxic than the others. In particular, the toxicities of Pb to vertebrate and fish were complicated as the SSD curves of Pb intersected with those of other heavy metals, while the SSD curves of Pb constructed by total species no longer crossed with others. The hazardous concentrations for 5 % of the species (HC5) affected were derived to determine the concentration protecting 95 % of species. The HC5 values of the six heavy metals were in the descending order: Zn > Pb > Cr > Cd > Hg > Cu, indicating toxicities in opposite order. Moreover, potential affected fractions were calculated to assess the ecological risks of different heavy metals at certain concentrations of the selected heavy metals. Evaluations of sensitivities of the species at various trophic levels and toxicity analysis of heavy metals are necessary prior to derivation of water quality criteria and the further environmental protection.

  8. Heavy exotic molecules

    Science.gov (United States)

    Liu, Yizhuang; Zahed, Ismail

    We briefly review the formation of pion-mediated heavy-light exotic molecules with both charm and bottom, under the general structures of chiral and heavy quark symmetries. The charm isosinglet exotic molecules with JPC = 1++ binds, which we identify as the reported neutral X(3872). The bottom isotriplet exotic with JPC = 1+1 binds, and is identified as a mixed state of the reported charged exotics Zb+(10610) and Zb-(10650). The bound bottom isosinglet molecule with JPC = 1++ is a possible neutral Xb(10532) to be observed.

  9. Nuclear reaction analysis (NRA) for trace element detection

    Energy Technology Data Exchange (ETDEWEB)

    Doebeli, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Noll, K. [Bern Univ. (Switzerland)

    1997-09-01

    Ion beam induced nuclear reactions can be used to analyse trace element concentrations in materials. The method is especially suited for the detection of light contaminants in heavy matrices. (author) 3 figs., 2 refs.

  10. Effect of soil moisture on trace elements concentrations using

    African Journals Online (AJOL)

    H. Sahraoui and M. Hachicha

    2017-01-01

    Jan 1, 2017 ... produced by the water influence moisture content and corrected ... Previous studies indicated that PXRF analysis was capable of detecting soil trace elements ..... determination of some heavy metals in soil using an x-ray ...

  11. Relations between Heavy-light Meson and Quark Masses

    Energy Technology Data Exchange (ETDEWEB)

    Brambilla, N.; Komijani, J.; Kronfeld, A. S.; Vairo, A.

    2017-12-13

    The study of heavy-light meson masses should provide a way to determine renormalized quark masses and other properties of heavy-light mesons. In the context of lattice QCD, for example, it is possible to calculate hadronic quantities for arbitrary values of the quark masses. In this paper, we address two aspects relating heavy-light meson masses to the quark masses. First, we introduce a definition of the renormalized quark mass that is free of both scale dependence and renormalon ambiguities, and discuss its relation to more familiar definitions of the quark mass. We then show how this definition enters a merger of the descriptions of heavy-light masses in heavy-quark effective theory and in chiral perturbation theory ($\\chi$PT). For practical implementations of this merger, we extend the one-loop $\\chi$PT corrections to lattice gauge theory with heavy-light mesons composed of staggered fermions for both quarks. Putting everything together, we obtain a practical formula to describe all-staggered heavy-light meson masses in terms of quark masses as well as some lattice artifacts related to staggered fermions. In a companion paper, we use this function to analyze lattice-QCD data and extract quark masses and some matrix elements defined in heavy-quark effective theory.

  12. Magnetic separation of algae

    Science.gov (United States)

    Nath, Pulak; Twary, Scott N.

    2016-04-26

    Described herein are methods and systems for harvesting, collecting, separating and/or dewatering algae using iron based salts combined with a magnetic field gradient to separate algae from an aqueous solution.

  13. Separation anxiety in children

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001542.htm Separation anxiety in children To use the sharing features on this page, please enable JavaScript. Separation anxiety in children is a developmental stage in which ...

  14. Separators for electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Steven Allen; Anakor, Ifenna Kingsley; Farrell, Greg Robert

    2018-01-16

    Provided are separators for use in an electrochemical cell comprising (a) an inorganic oxide and (b) an organic polymer, wherein the inorganic oxide comprises organic substituents. Also provided are electrochemical cells comprising such separators.

  15. Hydroponics reducing effluent's heavy metals discharge.

    Science.gov (United States)

    Rababah, Abdellah; Al-Shuha, Ahmad

    2009-01-01

    This paper investigates the capacity of Nutrient Film Technique (NFT) to control effluent's heavy metals discharge. A commercial hydroponic system was adapted to irrigate lettuces with primary treated wastewater for studying the potential heavy metals removal. A second commercial hydroponic system was used to irrigate the same type of lettuces with nutrient solution and this system was used as a control. Results showed that lettuces grew well when irrigated with primary treated effluent in the commercial hydroponic system. The NFT-plant system heavy metals removal efficiency varied amongst the different elements, The system's removal efficiency for Cr was more than 92%, Ni more than 85%, in addition to more than 60% reduction of B, Pb, and Zn. Nonetheless, the NFT-plants system removal efficiencies for As, Cd and Cu were lower than 30%. Results show that lettuces accumulated heavy metals in leaves at concentrations higher than the maximum acceptable European and Australian levels. Therefore, non-edible plants such as flowers or pyrethrum are recommended as value added crops for the proposed NFT.

  16. Precision Quantum Chromodynamics From Heavy Quark Expansions

    CERN Document Server

    Benson, D G

    2005-01-01

    The heavy quark expansion is applied to the semileptonic width of b → c and b → u transitions along with the moments of various decay distributions in the semileptonic b → c transitions. The resulting expressions can be used to improve the precision with which we can extract the values of the CKM matrix elements Vcb and Vub from the data. Heavy quark parameters like mb and m2p are also obtained with values that are completely consistent with theoretical expectations. The observed agreement between the theoretical predictions of the heavy quark expansion and the experimental data tightly constrain the theoretical uncertainty. The heavy quark expansion can also be applied to the photon energy moments in B → Xsγ. The first two of these moments are directly related to mb and m2p . The experimentally imposed cuts on the photon energy spectrum introduce biases into the extracted values of these parameters. Correcting for these biases generates a remarkable agreem...

  17. Meniscus Membranes For Separation

    Science.gov (United States)

    Dye, Robert C.; Jorgensen, Betty; Pesiri, David R.

    2005-09-20

    Gas separation membranes, especially meniscus-shaped membranes for gas separations are disclosed together with the use of such meniscus-shaped membranes for applications such as thermal gas valves, pre-concentration of a gas stream, and selective pre-screening of a gas stream. In addition, a rapid screening system for simultaneously screening polymer materials for effectiveness in gas separation is provided.

  18. Bioaccumulation of Heavy Metals

    African Journals Online (AJOL)

    komla

    acute toxicity and sublethal chronic action the devastating effects that the accumulation - ... surrounding waters. The results showed a programmes of heavy metals in aquatic strong and positive correlation (r = 0.97) ecosystems. between amounts of metals in the aquatic ...... Chemical composition of agricultural waste.

  19. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen...

  20. Heavy liquid bubble chamber

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    The CERN Heavy liquid bubble chamber being installed in the north experimental hall at the PS. On the left, the 1180 litre body; in the centre the magnet, which can produce a field of 26 800 gauss; on the right the expansion mechanism.

  1. Risk Assessment of Heavy Metals Contamination in Soils and Selected Crops in Zanjan Urban and Industrial Regions

    OpenAIRE

    Afshari, A.; H. Khademi; Sh. Ayoubi

    2016-01-01

    Introduction: Heavy metals are types of elements naturally present in soil or enter into soil as a result of human activities. The most important route of exposure to heavy metals is daily intake of food. Crops grown in contaminated soil (due to mining activities, industrial operations and agriculture) may contain high concentrations of heavy metals. Also closeness to cities and industrial centers can have a great influence on the accumulation of heavy metals to agricultural products grown in...

  2. Nuclear physics and heavy element research at LLNL

    Energy Technology Data Exchange (ETDEWEB)

    Stoyer, M A; Ahle, L E; Becker, J A; Bernstein, L A; Bleuel, D L; Burke, J T; Dashdorj, D; Henderson, R A; Hurst, A M; Kenneally, J M; Lesher, S R; Moody, K J; Nelson, S L; Norman, E B; Pedretti, M; Scielzo, N D; Shaughnessy, D A; Sheets, S A; Stoeffl, W; Stoyer, N J; Wiedeking, M; Wilk, P A; Wu, C Y

    2009-05-11

    This paper highlights some of the current basic nuclear physics research at Lawrence Livermore National Laboratory (LLNL). The work at LLNL concentrates on investigating nuclei at the extremes. The Experimental Nuclear Physics Group performs research to improve our understanding of nuclei, nuclear reactions, nuclear decay processes and nuclear astrophysics; an expertise utilized for important laboratory national security programs and for world-class peer-reviewed basic research.

  3. Super heavy element Copernicium: Cohesive and electronic properties revisited

    Science.gov (United States)

    Gyanchandani, Jyoti; Mishra, Vinayak; Dey, G. K.; Sikka, S. K.

    2018-01-01

    First principles scalar relativistic (SR) calculations with and without including the spin orbit (SO) interactions have been performed for solid Copernicium (Cn) to determine its ground state equilibrium structure, volume, bulk modulus, pressure derivative of the bulk modulus, density of states and band structure. Both SR and SR+SO calculations have been performed with 6p levels treated as part of core electrons and also as part of valence electrons. These calculations have been performed for the rhombohedral, BCT, FCC, HCP, BCC and SC structures. Results have been compared with the results for Hg which is lighter homologue of Cn in the periodic table. We find hcp to be the stable crystal structure at SR level of theory and also at SR+SO level of theory when the 6p electrons are treated as part of core electrons. With 6p as part of valence electrons, SR+SO level of computations, however, yield bcc structure to be the most stable structure. Equilibrium volume (V0) of the most stable crystal structure at SR level of theory viz. hcp structure is 188.66 a.u.3whereas its value for the bcc structure, the equilibrium ground state structure at SR+SO level of theory is 165.71 a.u.3 i.e a large change due to relativistic effects is seen. The density of states at Fermi level is much smaller in Cn than in Hg, making it a poorer metal than mercury. In addition the cohesive energy of Cn is computed to be almost two times that of Hg for SR+SO case.

  4. Determination of Essential Elements and Heavy Metals Contained in ...

    African Journals Online (AJOL)

    Salt is the oldest known food additive and still remains an essential requirement of any household contributing its own basic salty taste. This paper treats the different types of salt; industrial salt, table salt and refined salt. Table salt accounts for only a small part of the salt production in industrialized countries although ...

  5. Sorption interactions of heavy metals with biochar in soil remediation studies

    Science.gov (United States)

    Fristak, Vladimir; Friesl-Hanl, Wolfgang; Wawra, Anna; Soja, Gerhard

    2015-04-01

    The search for new materials in soil remediation applications has led to new conversion technologies such as carbonization and pyrolysis. Biochar represents the pyrolytic product of different biomass input materials processed at 350-1000°C and anoxic conditions. The pyrolysis temperature and feedstock have a considerable influence on the quality of the charred product and also its main physico-chemical properties. Biochar as porous material with large specific surface and C-stability is utilized in various environmental and agricultural technologies. Carbon sequestration, increase of soil water-holding capacity and pH as well as sorption of different xenobiotics present only a fraction of the multitude of biochar application possibilities. Heavy metals as potential sources of ecotoxicological risks are characterized by their non-degradability and the potential transfer into the food chain. Carbonaceous materials have been used for a long time as sorbents for heavy metals and organic contaminants in soil and water technologies. The similarity of biochar with activated carbon predetermines this material as remediation tool which plays an important role in heavy metal immobilization and retention with a parallel reduction in the risk of ground water and food crop contamination. In all this processes the element-specific sorption behaviour of biochar creates new conditions for pollutant binding. Sorption interaction and separation of contaminants from soil solution or waste effluent can be affected by wide-ranging parameters. In detail, our study was based on batch-sorption comparisons of two biochars produced from wood chips and green waste residues. We observed that sorption efficiency of biochar for model bivalent heavy metals (Cd, Zn, Cu) can be influenced by equilibrium parameters such as pH, contact time, initial concentration of metal in reaction solutions, presence of surfactants and chemical modification by acid hydrolysis, esterification and methylation. The

  6. Safety shutdown separators

    Science.gov (United States)

    Carlson, Steven Allen; Anakor, Ifenna Kingsley; Farrell, Greg Robert

    2015-06-30

    The present invention pertains to electrochemical cells which comprise (a) an anode; (b) a cathode; (c) a solid porous separator, such as a polyolefin, xerogel, or inorganic oxide separator; and (d) a nonaqueous electrolyte, wherein the separator comprises a porous membrane having a microporous coating comprising polymer particles which have not coalesced to form a continuous film. This microporous coating on the separator acts as a safety shutdown layer that rapidly increases the internal resistivity and shuts the cell down upon heating to an elevated temperature, such as 110.degree. C. Also provided are methods for increasing the safety of an electrochemical cell by utilizing such separators with a safety shutdown layer.

  7. Recovery vehicle and recovery system for heavy loads such as an aeroplane

    NARCIS (Netherlands)

    Lodewijks, G.; Van Deursen, M.; Van Deursen, J.

    2004-01-01

    The invention relates to a recovery vehicle suitable for heavy loads such as an aircraft, comprising a mobile chassis upon which a lifting element is provided and the lifting element comprises an air cushion. The lifting element comprises an adjustable lifting platform and the air cushion is

  8. A unified architecture of transcriptional regulatory elements

    DEFF Research Database (Denmark)

    Andersson, Robin; Sandelin, Albin Gustav; Danko, Charles G.

    2015-01-01

    Gene expression is precisely controlled in time and space through the integration of signals that act at gene promoters and gene-distal enhancers. Classically, promoters and enhancers are considered separate classes of regulatory elements, often distinguished by histone modifications. However...... and enhancers are considered a single class of functional element, with a unified architecture for transcription initiation. The context of interacting regulatory elements and the surrounding sequences determine local transcriptional output as well as the enhancer and promoter activities of individual elements....

  9. Acoustofluidic bacteria separation

    Science.gov (United States)

    Li, Sixing; Ma, Fen; Bachman, Hunter; Cameron, Craig E.; Zeng, Xiangqun; Huang, Tony Jun

    2017-01-01

    Bacterial separation from human blood samples can help with the identification of pathogenic bacteria for sepsis diagnosis. In this work, we report an acoustofluidic device for label-free bacterial separation from human blood samples. In particular, we exploit the acoustic radiation force generated from a tilted-angle standing surface acoustic wave (taSSAW) field to separate Escherichia coli from human blood cells based on their size difference. Flow cytometry analysis of the E. coli separated from red blood cells shows a purity of more than 96%. Moreover, the label-free electrochemical detection of the separated E. coli displays reduced non-specific signals due to the removal of blood cells. Our acoustofluidic bacterial separation platform has advantages such as label-free separation, high biocompatibility, flexibility, low cost, miniaturization, automation, and ease of in-line integration. The platform can be incorporated with an on-chip sensor to realize a point-of-care sepsis diagnostic device.

  10. A GAUGE-INVARIANT MULTIPOLE EXPANSION SCHEME FOR HEAVY-QUARK SYSTEMS IN QUANTUM CHROMODYNAMICS

    Energy Technology Data Exchange (ETDEWEB)

    Shizuya, Ken-ichi

    1980-09-01

    Separation of short-distance and long-distance dynamics for heavy quark-antiquark systems interacting with color gluons is investigated through a classification of gluons according to their ranges. A gauge-invariant double-multipole expansion scheme is constructed which takes into account color fluctuation of heavy-quark systems. Hadronic transitions between heavy quark-antiquark bound states as well as the static quark-antiquark potential are studied within this framework.

  11. Large scale separation and hadronic resonances from a new strongly interacting sector

    Science.gov (United States)

    Hasenfratz, A.; Rebbi, C.; Witzel, O.

    2017-10-01

    Many theories describing physics beyond the Standard Model rely on a large separation of scales. Large scale separation arises in models with mass-split flavors if the system is conformal in the ultraviolet but chirally broken in the infrared. Because of the conformal fixed point, these systems exhibit hyperscaling and a highly constrained resonance spectrum. We derive hyperscaling relations and investigate the realization of one such system with four light and eight heavy flavors. Our numerical simulations confirm that both light-light and heavy-heavy resonance masses show hyperscaling and depend only on the ratio of the light and heavy flavor masses. The heavy-heavy spectrum is qualitatively different from QCD and exhibits quarkonia with masses not proportional to the constituent quark mass. These resonances are only a few times heavier than the light-light ones, which would put them within reach of the LHC.

  12. Separation of Transplutonium Elements from Neutron Irradiated Americium-241

    National Research Council Canada - National Science Library

    UENO, Kaoru; WATANABE, Kenju; SAGAWA, Chiaki; ISHIMORI, Tomitaro

    1974-01-01

    .... The ratios of the amounts present of these isotopes were determined by mass spectrometry. It was not possible to identify 249Bk in the berkelium fraction owing to the interference from other β-ray emitting nuclides. In the californium fraction, both spontaneous fission and a-activities due to 250, 252 were observed.

  13. Solar cell element

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Satoru; Matsukuma, Kunihiro; Kokuuchi, Shigeru; Morita, Keiichi; Yagi, Hideyuki.

    1989-07-17

    This invention aims to provide a soalr cell element with an easily formable electrode having an independent BSF and BSR. For this purpose, in this invention, a layer with high concentration of impurities (which functions as BSF on the opposite surface of the light-receiving surface) is partly and adjacently placed; a back electrode is made to have an ohmic resistance to the high-impurity layer; a metal oxide film is forther placed in other parts. By this, the functions of BSF and BSR are sufficiently utilized as a boundary surface between the high-impurity layer (BSF) and the semi-conductor substrate and the metal oxide film (BSR) are separated, thus enhancing the conversion efficiency. As for the patterns on the separated layers of BSF and BSR, various patterns are possible to be relized by using resist printing patterns. 3 figs.

  14. 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.

  15. Detecting heavy quarks

    Energy Technology Data Exchange (ETDEWEB)

    Benenson, G.; Chau, L.L.; Ludlam, T.; Paige, F.E.; Platner, E.D.; Protopopescu, S.D.; Rehak, P.

    1983-01-01

    In this exercise we examine the performance of a detector specifically configured to tag heavy quark (HQ) jets through direct observations of D-meson decays with a high resolution vertex detector. To optimize the performance of such a detector, we assume the small diamond beam crossing configuration as described in the 1978 ISABELLE proposal, giving a luminosity of 10/sup 32/ cm/sup -2/ sec/sup -1/. Because of the very large backgrounds from light quark (LQ) jets, most triggering schemes at this luminosity require high P/sub perpendicular to/ leptons and inevitably give missing neutrinos. If alternative triggering schemes could be found, then one can hope to find and calculate the mass of objects decaying to heavy quarks. A scheme using the high resolution detector will also be discussed in detail. The study was carried out with events generated by the ISAJET Monte Carlo and a computer simulation of the described detector system. (WHK)

  16. SUPRI Heavy Oil Research Program: Twelfth annual report, October 1, 1987--September 30, 1988

    Energy Technology Data Exchange (ETDEWEB)

    Brigham, W. E.; Castanier, L. M.

    1989-06-01

    The following research programs on heavy oil recovery are presented: flow properties; in-situ combustion; steam injection with additives; reservoir definition; and field support services. Individual projects are processed separately for the data bases. (CBS)

  17. Trends in Supersonic Separator design development

    Directory of Open Access Journals (Sweden)

    Altam Rami Ali

    2017-01-01

    Full Text Available Supersonic separator is a new technology with applications in hydrocarbon dew pointing and gas dehydration which can be used to condensate and separate water and heavy hydrocarbons from natural gas. Many researchers have studied the design, performance and efficiency, economic viability, and industrial applications of these separators. The purpose of this paper is to succinctly review recent progress in the design and application of supersonic separators and their limitations. This review has found that while several aspects of this study are well studied, considerable gaps within the published literature still exists in the areas such as turndown flexibility which is a critical requirement to cater for variation of mass flow and since almost all the available designs have a fixed geometry and therefore cannot be considered suitable for variable mass flow rate, which is a common situation in actual site. Hence, the focus needs to be more on designing a flexible geometry that can maintain a high separation efficiency regardless of inlet conditions and mass flow variations. This review is focusing only on the design and application of the supersonic separators without going through the experimental facilities, industrial platform, pilot plants as well as theoretical, analytical, and numerical modelling.

  18. Advanced Aqueous Separation Systems for Actinide Partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Nash, Kenneth L.; Clark, Sue; Meier, G Patrick; Alexandratos, Spiro; Paine, Robert; Hancock, Robert; Ensor, Dale

    2012-03-21

    One of the most challenging aspects of advanced processing of spent nuclear fuel is the need to isolate transuranium elements from fission product lanthanides. This project expanded the scope of earlier investigations of americium (Am) partitioning from the lanthanides with the synthesis of new separations materials and a centralized focus on radiochemical characterization of the separation systems that could be developed based on these new materials. The primary objective of this program was to explore alternative materials for actinide separations and to link the design of new reagents for actinide separations to characterizations based on actinide chemistry. In the predominant trivalent oxidation state, the chemistry of lanthanides overlaps substantially with that of the trivalent actinides and their mutual separation is quite challenging.

  19. Long term effect of municipal solid waste amendment on soil heavy ...

    African Journals Online (AJOL)

    AJL

    element contents of periurban areas soils was carried out in Ngaoundere. Waste samples were collected in ... Key words: Heavy metals, soils, municipal solid wastes, amendment, bioavailability factor. INTRODUCTION. Waste management .... Physico-chemical composition and heavy metal contents of urban wastes.

  20. Utah Heavy Oil Program

    Energy Technology Data Exchange (ETDEWEB)

    J. Bauman; S. Burian; M. Deo; E. Eddings; R. Gani; R. Goel; C.K. Huang; M. Hogue; R. Keiter; L. Li; J. Ruple; T. Ring; P. Rose; M. Skliar; P.J. Smith; J.P. Spinti; P. Tiwari; J. Wilkey; K. Uchitel

    2009-10-20

    The Utah Heavy Oil Program (UHOP) was established in June 2006 to provide multidisciplinary research support to federal and state constituents for addressing the wide-ranging issues surrounding the creation of an industry for unconventional oil production in the United States. Additionally, UHOP was to serve as an on-going source of unbiased information to the nation surrounding technical, economic, legal and environmental aspects of developing heavy oil, oil sands, and oil shale resources. UHOP fulGilled its role by completing three tasks. First, in response to the Energy Policy Act of 2005 Section 369(p), UHOP published an update report to the 1987 technical and economic assessment of domestic heavy oil resources that was prepared by the Interstate Oil and Gas Compact Commission. The UHOP report, entitled 'A Technical, Economic, and Legal Assessment of North American Heavy Oil, Oil Sands, and Oil Shale Resources' was published in electronic and hard copy form in October 2007. Second, UHOP developed of a comprehensive, publicly accessible online repository of unconventional oil resources in North America based on the DSpace software platform. An interactive map was also developed as a source of geospatial information and as a means to interact with the repository from a geospatial setting. All documents uploaded to the repository are fully searchable by author, title, and keywords. Third, UHOP sponsored Give research projects related to unconventional fuels development. Two projects looked at issues associated with oil shale production, including oil shale pyrolysis kinetics, resource heterogeneity, and reservoir simulation. One project evaluated in situ production from Utah oil sands. Another project focused on water availability and produced water treatments. The last project considered commercial oil shale leasing from a policy, environmental, and economic perspective.

  1. Heavy metals in vegetables and potential risk for human health

    Directory of Open Access Journals (Sweden)

    Fernando Guerra

    2012-02-01

    Full Text Available Ingestion of vegetables containing heavy metals is one of the main ways in which these elements enter the human body. Once entered, heavy metals are deposited in bone and fat tissues, overlapping noble minerals. Slowly released into the body, heavy metals can cause an array of diseases. This study aimed to investigate the concentrations of cadmium, nickel, lead, cobalt and chromium in the most frequently consumed foodstuff in the São Paulo State, Brazil and to compare the heavy metal contents with the permissible limits established by the Brazilian legislation. A value of intake of heavy metals in human diets was also calculated to estimate the risk to human health. Vegetable samples were collected at the São Paulo General Warehousing and Centers Company, and the heavy metal content was determined by atomic absorption spectrophotometry. All sampled vegetables presented average concentrations of Cd and Ni lower than the permissible limits established by the Brazilian legislation. Pb and Cr exceeded the limits in 44 % of the analyzed samples. The Brazilian legislation does not establish a permissible limit for Co contents. Regarding the consumption habit of the population in the São Paulo State, the daily ingestion of heavy metals was below the oral dose of reference, therefore, consumption of these vegetables can be considered safe and without risk to human health.

  2. Dustfall Heavy Metal Pollution During Winter in North China.

    Science.gov (United States)

    Xiong, Qiu-lin; Zhao, Wen-ji; Guo, Xiao-yu; Shu, Tong-tong; Chen, Fan-tao; Zheng, Xiao-xia; Gong, Zhao-ning

    2015-10-01

    In order to study heavy metal pollution in dustfall during Winter in North China, forty-four dustfall samples were collected in North China Region from November 2013 to March 2014. Then forty trace elements content were measured for each sample by inductively coupled plasma-mass spectrometry. Finally, the contamination characteristics of the main heavy metals were studied through a multi-method analysis, including variability analysis, Pearson correlation analysis and principal component analysis. Results showed that the relative contents of cadmium (Cd), zinc (Zn), copper (Cu), bismuth (Bi), lead (Pb) exceeded the standards stipulated in Chinese soil elements background values by amazing 4.9 times. In this study, conclusions were drawn that dustfall heavy metal pollution in the region was mainly caused by transport pollution, metallurgy industrial pollution, coal pollution and steel industrial pollution.

  3. Biomonitoring of heavy metals using Usnea antarctica lichens (extended abstract)

    Czech Academy of Sciences Publication Activity Database

    Zvěřina, O.; Coufalík, Pavel; Barták, M.; Komárek, J.

    2016-01-01

    Roč. 6, č. 2 (2016), s. 238-239 ISSN 1805-0689. [Biosciences in Polar and Alpine Research. Workshop 2016. Brno, 23.11.2016-23.11.2016] Institutional support: RVO:68081715 Keywords : heavy metal * lichen * Antarctica Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry

  4. Environmental research on actinide elements

    Energy Technology Data Exchange (ETDEWEB)

    Pinder, J.E. III; Alberts, J.J.; McLeod, K.W.; Schreckhise, R.G. (eds.)

    1987-08-01

    The papers synthesize the results of research sponsored by DOE's Office of Health and Environmental Research on the behavior of transuranic and actinide elements in the environment. Separate abstracts have been prepared for the 21 individual papers. (ACR)

  5. The ADvanced SEParation (ADSEP)

    Science.gov (United States)

    1998-01-01

    The ADvanced SEParation (ADSEP) commercial payload is making use of major advances in separation technology: The Phase Partitioning Experiment (PPE); the Micorencapsulation experiment; and the Hemoglobin Separation Experiment (HSE). Using ADSEP, commercial researchers will attempt to determine the partition coefficients for model particles in a two-phase system. With this information, researchers can develop a higher resolution, more effective cell isolation procedure that can be used for many different types of research and for improved health care. The advanced separation technology is already being made available for use in ground-based laboratories.

  6. Separation of flow

    CERN Document Server

    Chang, Paul K

    2014-01-01

    Interdisciplinary and Advanced Topics in Science and Engineering, Volume 3: Separation of Flow presents the problem of the separation of fluid flow. This book provides information covering the fields of basic physical processes, analyses, and experiments concerning flow separation.Organized into 12 chapters, this volume begins with an overview of the flow separation on the body surface as discusses in various classical examples. This text then examines the analytical and experimental results of the laminar boundary layer of steady, two-dimensional flows in the subsonic speed range. Other chapt

  7. Heavy oil markets and investments

    Energy Technology Data Exchange (ETDEWEB)

    Forrest, Jackie [CERA North America (United States)

    2011-07-01

    With the depletion of traditional energy resources and the rising demand for energy, the exploitation of heavy oil resources is increasing. The aim of this paper is to present the heavy oil sector and to show which are the factors influencing heavy oil growth and production. A large part of heavy oil reserves lies in the Americas, with about 45% of the world's reserves in Latin America and over 35% in North America. The development of the heavy oil sector is dependent on economic, technological and environmental factors; greenhouse gas policies have important impacts on the development of the heavy oil industry as well as downstream market access. This presentation highlighted the great potential that North and South America have in terms of heavy oil but that the development of this sector will depend on several factors.

  8. Residency of rhenium and osmium in a heavy crude oil

    Science.gov (United States)

    DiMarzio, Jenna M.; Georgiev, Svetoslav V.; Stein, Holly J.; Hannah, Judith L.

    2018-01-01

    Rhenium-osmium (Re-Os) isotope geochemistry is an emerging tool for the study of oil formation and migration processes, and a new technology for petroleum exploration. Little is known, however, about the residency of Re and Os within asphaltene and maltene sub-fractions of crude oil. This information is crucial for understanding the 187Re-187Os radiometric clock held in petroleum systems and for interpreting geochronology for key processes such as oil formation, migration, and biodegradation. In this study, a heavy crude oil was separated into soluble (maltene, MALT) and insoluble (asphaltene, ASPH) fractions using n-heptane as the asphaltene-precipitating agent. The asphaltenes were separated sequentially into sub-fractions using two different solvent pairs (heptane-dichloromethane and acetone-toluene), and the bulk maltenes were separated into saturate, aromatic, and resin (SAR) fractions using open column chromatography. Each asphaltene and maltene sub-fraction was analyzed for Re and Os. The asphaltene sub-fractions and the bulk ASPH, MALT, and crude oil were analyzed for a suite of trace metals by ICP-MS. Our results show that Re and Os concentrations co-vary between the asphaltene sub-fractions, and that both elements are found mostly in the more polar and aromatic sub-fractions. Significant Re and Os are also present in the aromatic and resin fractions of the maltenes. However, each asphaltene and maltene sub-fraction has a distinct isotopic composition, and sub-fractions are not isochronous. This suggests that asphaltene sub-fractionation separates Re-Os complexes to the point where the isotopic integrity of the geochronometer is compromised. The mobility of individual Re and Os isotopes and the decoupling possibilities between radiogenic 187Os produced from 187Re remain elusive, but their recognition in this study is a critical first step. Re and Os correlate strongly with Mo and Cd in the asphaltene sub-fractions, suggesting that these metals occupy

  9. Assessment of heavy metals concentration in water, soil sediment ...

    African Journals Online (AJOL)

    The term heavy metal refers to any metallic chemical element that has a relatively high density and is toxic at low concentrations. This study was conducted in four eastern Rift Valley lakes which included Lakes Oloidien, Crater, Elementaita and Nakuru, to determine the presence and levels of lead, arsenic, cadmium and ...

  10. INTRODUCTION Heavy metal pollution of water has become a ...

    African Journals Online (AJOL)

    major environmental problem almost since the advent of agricultural ... Nations state that monitoring eight elements in fish Hg, Cd, Pb, As, Cu, ..... Research J. Environ. Science, 3 (5):522-529. Staniskiene, B.; Matusevicius, P.; Budreckiene, R. and Skibniewska, K.A. 2006. Distribution of heavy metals in tissues of freshwater.

  11. Elastic recoil detection (ERD) with extremely heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Forster, J.S. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Currie, P.J. [Royal Tyrrell Museum, Drumheller, Alberta T0J 0Y0 (Canada); Davies, J.A. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Siegele, R. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Wallace, S.G. [Accelerator Laboratory, McMaster University, Hamilton, Ontario L8S 4M1 (Canada); Zelenitsky, D. [Department of Geology and Geophysics, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)

    1996-06-01

    Extremely heavy-ion beams such as {sup 209}Bi in elastic recoil detection (ERD) make ERD a uniquely valuable technique for thin-film analysis of elements with mass {<=}100. We report ERD measurements of compositional analysis of dinosaur eggshells and bones. We also show the capability of the ERD technique on studies of thin-film, high-temperature superconductors. (orig.).

  12. Regional ecotoxicological hazards associated with anthropogenic enrichment of heavy metals

    NARCIS (Netherlands)

    Spijker, J.H.; Mol, G.; Posthuma, L.

    2011-01-01

    Regional geochemical data of heavy metals are commonly used for environmental risk assessment and management. Often these data are based on so-called total concentrations, whereas the exposure to the mobile or reactive fraction of these elements finally determines whether the exposed ecosystem is at

  13. Nutritional composition, vitamins, minerals and toxic heavy metals ...

    African Journals Online (AJOL)

    This study aimed at analyzing the nutritional potential of a wild edible plant, Trianthema portulacastrum L. widely used in Peshawar, Khyber Pakhtunkhwa, Pakistan. The nutritional composition, vitamins, minerals and heavy elements were analyzed following the standard methods of Association of Official Analytical ...

  14. Phytoremediation of Heavy Metals in Aqueous Solutions

    OpenAIRE

    Felix Aibuedefe AISIEN; Oluwole FALEYE; Eki Tina AISIEN

    2010-01-01

    One of the major environmental problems is the pollution of water and soil by toxic heavy metals. This study investigated the phytoremediation potential of water hyacinth, for the removal of cadmium (Cd), lead (Pb) and zinc (Zn). Water hyacinths were cultured in bore-hole water, supplemented with 5mg/l of Zn and Pb and 1mg/l of Cd at pH 4.5, 6.8 and 8.5. The plants were separately harvested each week for six weeks. The results showed that removal of these metals from solution was fast especia...

  15. heavy ion acceleration at shocks

    Science.gov (United States)

    Shevchenko, V. I.; Galinsky, V.

    2009-12-01

    The theoretical study of alpha particle acceleration at a quasi-parallel shock due to interaction with Alfven waves self-consistently excited in both upstream and downstream regions was conducted using a scale-separation model [1]. The model uses conservation laws and resonance conditions to find where waves will be generated or dumped and hence particles will be pitch--angle scattered as well as the change of the wave energy due to instability or damping. It includes in consideration the total distribution function (the bulk plasma and high energy tail), so no any assumptions (e.g. seed populations, or some ad-hoc escape rate of accelerated particles) are required. In previous studies heavy ions were treated as perfect test particles, they only experienced the Alfven turbulence excited by protons and didn’t contribute to turbulence generation. In contrast to this approach, we consider the ion scattering on hydromagnetic turbulence generated by both protons and ions themselves. It is important for alpha particles with their relatively large mass-loading parameter that defines efficiency of the wave excitation by alpha particles. The energy spectra of alpha particles is found and compared with those obtained in test particle approximation. [1] Galinsky, V.L., and V.I. Shevchenko, Astrophys. J., 669, L109, 2007.

  16. Mineralogy and geochemistry of density-separated Greek lignite fractions

    NARCIS (Netherlands)

    Iordanidis, A.; Doesburg, van J.D.J.

    2006-01-01

    In this study, lignite samples were collected from the Ptolemais region, northern Greece, homogenized, crushed to less than I nun, and separated in three density fractions using heavy media. The mineralogical investigation of the density fractions showed a predominance of pyrite in the light

  17. Effective Removal of Heavy Metal Ions Using Glycerol and Starch Xanthate

    Directory of Open Access Journals (Sweden)

    Aliyu Mohammed

    2017-09-01

    Full Text Available Glycerol and insoluble starch xanthates were synthesised and effectively used in the removal of Pb, Cd and Cu from aqueous solutions. The insoluble metal complex formed between the sulphur atoms in the xanthates and the heavy metals were easily separated. Lower dosage of glycerol xanthate was required in each case, with the optimum molar ratio (M2+/GX of 2. Moreover, the use of glycerol xanthate required no pH adjustments to give a 100 % heavy metal removal within the range of the detection limit. As for the ISX, there was a remarkable metal scavenging activity when the ISX contained high amount of Sulphur per molecule (10.12% S and when the pH was adjusted to 6. Butyl xanthate was also synthesised to make a good comparison with the glycerol and insoluble starch xanthate. The xanthates from these two sustainable materials (Starch and glycerol are proven to be more effective in metal scavenging activity. FTIR and CHNS elemental analyses were used to prove the evidence of xanthation, in addition, 13C NMR was used to characterise the glycerol xanthate.

  18. Superconducting, energy variable heavy ion linac with constant β, multicell cavities of CH-type

    Directory of Open Access Journals (Sweden)

    S. Minaev

    2009-12-01

    Full Text Available An energy variable ion linac consisting of multigap, constant-β cavities was developed. The effect of phase sliding, unavoidable in any constant-β section, is leading to a coherent rf phase motion, which fits well to the H-type structures with their long π-mode sections and separated lenses. The exact periodicity of the cell lengths within each cavity results in technical advantages, such as higher calculation accuracy when only one single period can be simulated, simpler manufacturing, and tuning. This is most important in the case of superconducting cavities. By using this concept, an improved design for a 217 MHz cw superconducting heavy ion linac with energy variation has been worked out. The small output energy spread of ±3  AkeV is provided over the whole range of energy variation from 3.5 to 7.3 AMeV. These capabilities would allow for a competitive research in the field of radiochemistry and for a production of super heavy elements (SHE, especially. A first 19-cell cavity of that type was designed, built, and rf tested successfully at the Institute for Applied Physics (IAP Frankfurt. A 325.224 MHz, seven-cell cavity with constant β=0.16 is under development and will be operated in a frequency controlled mode. It will be equipped with a power coupler and beam tests with Unilac beams at GSI are foreseen.

  19. Nonterminal Separating Macro Grammars

    NARCIS (Netherlands)

    Hogendorp, Jan Anne

    1987-01-01

    We extend the concept of nonterminal separating (or NTS) context-free grammar to nonterminal separating $m$-macro grammar where the mode of derivation $m$ is equal to "unrestricted". "outside-in' or "inside-out". Then we show some (partial) characterization results for these NTS $m$-macro grammars.

  20. Working with Separation

    Science.gov (United States)

    Krugman, Dorothy C.

    1971-01-01

    Discusses the role of the caseworker in providing support to children experiencing separation from their families and emphasizes the need to recognize that there are differences between those separation experiences dictated by the needs of children and those dictated by arbitrary or noncasework factors. (AJ)

  1. Separation anxiety disorder

    NARCIS (Netherlands)

    Nauta, M.H.; Emmelkamp, P.M.G.; Sturmey, P.; Hersen, M.

    2012-01-01

    Separation anxiety disorder (SAD) is the only anxiety disorder that is specific to childhood; however, SAD has hardly ever been addressed as a separate disorder in clinical trials investigating treatment outcome. So far, only parent training has been developed specifically for SAD. This particular

  2. Social Separation in Monkeys.

    Science.gov (United States)

    Mineka, Susan; Suomi, Stephen J.

    1978-01-01

    Reviews phenomena associated with social separation from attachment objects in nonhuman primates. Evaluates four theoretical treatments of separation in light of existing data: Bowlby's attachment-object-loss theory, Kaufman's conservation-withdrawal theory, Seligman's learned helplessness theory, and Solomon and Corbit's opponent-process theory.…

  3. Heavy-heavy and heavy-light quarks interactions generated by QCD vacuum

    Directory of Open Access Journals (Sweden)

    Musakhanov Mirzayusuf

    2017-01-01

    Full Text Available The QCD vacuum is populated by instantons that correspond to the tunneling processes in the vacuum. This mechanism creates the strong vacuum gluon fields. As result, the QCD vacuum instantons induce very strong interactions between light quarks, initially almost massless. Such a strong interactions bring a large dynamical mass M of the light quarks and bound them to produce almost massless pions in accordance with the spontaneous breaking of the chiral symmetry (SBCS. On the other hand, the QCD vacuum instantons also interact with heavy quarks and responsible for the generation of the heavy-heavy and heavy-light quarks interactions, with a traces of the SBCS. If we take the average instanton size ρ¯=0.33$\\bar \\rho = 0.33$ fm, and the average inter-instanton distance R¯=1$\\bar R = 1$ fm we obtain the dynamical light quark mass to be M = 365 MeV and the instanton media contribution to the heavy quark mass ΔM=70 MeV. These factors define the coupling between heavy-light and heavy-heavy quarks induced by the QCD vacuum instantons. We consider first the instanton effects on the heavy-heavy quarks potential, including its spin-dependent part. We also discuss those effects on the masses of the charmonia and their hyperfine mass splittings. At the second part we discuss the interaction between a heavy and light quarks generated by instantons and it’s effects.

  4. Production of High-Purity Anhydrous Nickel(II) Perrhenate for Tungsten-Based Sintered Heavy Alloys.

    Science.gov (United States)

    Leszczyńska-Sejda, Katarzyna; Benke, Grzegorz; Kopyto, Dorota; Majewski, Tomasz; Drzazga, Michał

    2017-04-24

    This paper presents a method for the production of high-purity anhydrous nickel(II) perrhenate. The method comprises sorption of nickel(II) ions from aqueous nickel(II) nitrate solutions, using strongly acidic C160 cation exchange resin, and subsequent elution of sorbed nickel(II) ions using concentrated perrhenic acid solutions. After the neutralization of the resulting rhenium-nickel solutions, hydrated nickel(II) perrhenate is then separated and then dried at 160 °C to obtain the anhydrous form. The resulting compound is reduced in an atmosphere of dissociated ammonia in order to produce a Re-Ni alloy powder. This study provides information on the selected properties of the resulting Re-Ni powder. This powder was used as a starting material for the production of 77W-20Re-3Ni heavy alloys. Microstructure examination results and selected properties of the produced sintered heavy alloys were compared to sintered alloys produced using elemental W, Re, and Ni powders. This study showed that the application of anhydrous nickel(II) perrhenate in the production of 77W-20Re-3Ni results in better properties of the sintered alloys compared to those made from elemental powders.

  5. Production of High-Purity Anhydrous Nickel(II Perrhenate for Tungsten-Based Sintered Heavy Alloys

    Directory of Open Access Journals (Sweden)

    Katarzyna Leszczyńska-Sejda

    2017-04-01

    Full Text Available This paper presents a method for the production of high-purity anhydrous nickel(II perrhenate. The method comprises sorption of nickel(II ions from aqueous nickel(II nitrate solutions, using strongly acidic C160 cation exchange resin, and subsequent elution of sorbed nickel(II ions using concentrated perrhenic acid solutions. After the neutralization of the resulting rhenium-nickel solutions, hydrated nickel(II perrhenate is then separated and then dried at 160 °C to obtain the anhydrous form. The resulting compound is reduced in an atmosphere of dissociated ammonia in order to produce a Re-Ni alloy powder. This study provides information on the selected properties of the resulting Re-Ni powder. This powder was used as a starting material for the production of 77W-20Re-3Ni heavy alloys. Microstructure examination results and selected properties of the produced sintered heavy alloys were compared to sintered alloys produced using elemental W, Re, and Ni powders. This study showed that the application of anhydrous nickel(II perrhenate in the production of 77W-20Re-3Ni results in better properties of the sintered alloys compared to those made from elemental powders.

  6. Advances in chemical investigations of the heaviest elements

    Directory of Open Access Journals (Sweden)

    Türler Andreas

    2016-01-01

    Full Text Available Although somewhat in the shadow of the discoveries of new elements, experimental chemical investigations of the heaviest elements have made tremendous progress in the last decades. Indeed, it was possible to experimentally determine thermochemical properties of heavy transactinide elements such as copernicium or flerovium. But will it be possible to chemically study all currently known elements of the periodic table up to element 118? While it is experimentally feasible to work with single atoms, the short half-lives of even the longest currently known isotopes of elements 115 through 118 call for new experimental approaches.

  7. The Cluster Orbits With Perturbations of Keplerian Elements (COWPOKE) Equations

    National Research Council Canada - National Science Library

    Sabol, Chris

    2004-01-01

    .... Given mean Keplerian elements and element differences, the COWPOKE equations describe spherical radial, cross-track, and along-track separations of the satellites as an explicit function of time...

  8. With modern equipment heavy crude is produced

    Energy Technology Data Exchange (ETDEWEB)

    1968-10-01

    Venezuela's Corporacion Venezolana del Petroleo (CVP) is handling heavy crude production at its Boscan Field, using modern facilities. For generating steam, the station has 2 boilers: one is direct fired and the other takes advantage of the waste heat from the turbines. To prevent plugging of the pipeline, when it is necessary to suspend operations, the crude is displaced with water. Delays are not frequent but can occur if problems arise due to difficulties with the boilers. The treating separators, one vertical and the other horizontal, have 2 heaters: one is in the upstream circuit and the other is in the downstream circuit. The crude is separated from naphtha and water in an expansion tower. Three compressors furnish gas to the gas turbines. The suction pressure is 80 psi and the discharge pressure is 150 psi. The waste from the turbines is taken advantage of by the steam generator in one of the station boilers.

  9. Magnetotactic bacteria. Promising biosorbents for heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Wei; Zhang, Yanzong; Ding, Xiaohui; Liu, Yan; Shen, Fei; Zhang, Xiaohong; Deng, Shihuai; Xiao, Hong; Yang, Gang; Peng, Hong [Sichuan Agricultural Univ., Chengdu (China). Provincial Key Lab. of Agricultural Environmental Engineering

    2012-09-15

    Magnetotactic bacteria (MTB), which can orient and migrate along a magnetic line of force due to intracellular nanosized magnetosomes, have been a subject of research in the medical field, in dating environmental changes, and in environmental remediation. This paper reviews the recent development of MTB as biosorbents for heavy metals. Ultrastructures and taxis of MTB are investigated. Adsorptions in systems of unitary and binary ions are highlighted, as well as adsorption conditions (temperature, pH value, biomass concentration, and pretreatments). The separation and desorption of MTB in magnetic separators are also discussed. A green method to produce metal nanoparticles is provided, and an energy-efficient way to recover precious metals is put forward during biosorption. (orig.)

  10. Bacterial Cell Surface Adsorption of Rare Earth Elements

    Science.gov (United States)

    Jiao, Y.; Park, D.; Reed, D.; Fujita, Y.; Yung, M.; Anderko, A.; Eslamimanesh, A.

    2015-12-01

    Rare earth elements (REE) play a critical role in many emerging clean energy technologies, including high-power magnets, wind turbines, solar panels, hybrid/electric vehicle batteries and lamp phosphors. In order to sustain demand for such technologies given current domestic REE shortages, there is a need to develop new approaches for ore processing/refining and recycling of REE-containing materials. To this end, we have developed a microbially-mediated bioadsorption strategy with application towards enrichment of REE from complex mixtures. Specifically, the bacterium Caulobacter crescentus was genetically engineered to display lanthanide binding tags (LBTs), short peptides that possess high affinity and specificity for rare earth elements, on its cell surface S-layer protein. Under optimal conditions, LBT-displayed cells adsorbed greater than 5-fold more REE than control cells lacking LBTs. Competition binding experiments with a selection of REEs demonstrated that our engineered cells could facilitate separation of light- from heavy- REE. Importantly, binding of REE onto our engineered strains was much more favorable compared to non-REE metals. Finally, REE bound to the cell surface could be stripped off using citrate, providing an effective and non-toxic REE recovery method. Together, this data highlights the potential of our approach for selective REE enrichment from REE containing mixtures.

  11. Contamination of Kallar Kahar Lake by Inorganic Elements and ...

    African Journals Online (AJOL)

    The present study was conducted to find out the contamination of Kallar Kahar Lake by inorganic elements and heavy metals and the temporal variation of these chemicals in the lake water. Water samples were collected on monthly basis during December 2001 to November 2002. Concentration of 10 inorganic elements ...

  12. 0 Elemental Composition of Atmospheric Particulate Matter during ...

    African Journals Online (AJOL)

    Michael Horsfall

    analysed for the PM mass by weighing. A further analysis was performed for 25 elements by particle-induced x-ray emission spectrometry. The results show that the concentrations of the heavy metals were lower than those for the elements of crustal origin. The data from PIXE analysis and enrichment factor (E.F.) calculation ...

  13. [Analysis of distribution and contents of heavy metal pollution in fish body with laser-induced breaddown spectroscopy].

    Science.gov (United States)

    Wan, Xiong; Wang, Jian-Yu; Ye, Jian-Hua; Wang, Peng; Zhang, Zhi-Min

    2013-01-01

    Environmental pollution can cause poisoning, disease and death of organisms, and the absorption and the accumulation of different biological tissues on pollutants are different. The absorption of heavy metal elements of various biological tissues on pollutants is an important biomedical research problem. In the present paper, a laser induced breakdown spectroscopy (LIBS) method was used to quantitatively analyze heavy metal elements in various tissues of some contaminated fish samples. Optimal experimental parameters were obtained in the LIBS experiments for these fish samples, calibration curves for plumbum and barium elements were fitted and the contents of heavy metal elements were determined with the external calibration approach. Experimental results showed that there was the heavy metal accumulation in fish liver mouth, and gills etc, however the heavy metal content in fish meat is very low. The proposed method can be used for the assessment studies of the influence of pollution on the organisms, and can be promoted in the biomedical fields.

  14. Heavy Metals Acting as Endocrine Disrupters

    Directory of Open Access Journals (Sweden)

    Bogdan Georgescu

    2011-10-01

    Full Text Available Last years researches focused on several natural and synthetic compounds that may interfere with the major functionsof the endocrine system and were termed endocrine disrupters. Endocrine disrupters are defined as chemicalsubstances with either agonist or antagonist endocrine effects in human and animals. These effects may be achievedby interferences with the biosynthesis or activity of several endogenous hormones. Recently, it was demonstratedthat heavy metals such as cadmium (Cd, arsen (As, mercury (Hg, nickel (Ni, lead (Pb and zinc (Zn may exhibitendocrine-disrupting activity in animal experiments. Emerging evidence of the intimate mechanisms of action ofthese heavy metals is accumulating. It was revealed, for example, that the Zn atom from the Zn fingers of theestrogen receptor can be replaced by several heavy metal molecules such as copper, cobalt, Ni and Cd. By replacingthe Zn atom with Ni or copper, binding of the estrogen receptor to the DNA hormone responsive elements in the cellnucleus is prevented. In both males and females, low-level exposure to Cd interferes with the biological effects ofsteroid hormones in reproductive organs. Arsen has the property to bind to the glucocorticoid receptor thusdisturbing glucocorticoids biological effects. With regard to Hg, this may induce alterations in male and femalefertility, may affect the function of the hypothalamo-pituitary-thyroid axis or the hypothalamo-pituitary-adrenal axis,and disrupt biosynthesis of steroid hormones.

  15. Analysis of heavy oils: Method development and application to Cerro Negro heavy petroleum

    Energy Technology Data Exchange (ETDEWEB)

    Carbognani, L.; Hazos, M.; Sanchez, V. (INTEVEP, Filial de Petroleos de Venezuela, SA, Caracas (Venezuela)); Green, J.A.; Green, J.B.; Grigsby, R.D.; Pearson, C.D.; Reynolds, J.W.; Shay, J.Y.; Sturm, G.P. Jr.; Thomson, J.S.; Vogh, J.W.; Vrana, R.P.; Yu, S.K.T.; Diehl, B.H.; Grizzle, P.L.; Hirsch, D.E; Hornung, K.W.; Tang, S.Y.

    1989-12-01

    On March 6, 1980, the US Department of Energy (DOE) and the Ministry of Energy and Mines of Venezuela (MEMV) entered into a joint agreement which included analysis of heavy crude oils from the Venezuelan Orinoco oil belt.The purpose of this report is to present compositional data and describe new analytical methods obtained from work on the Cerro Negro Orinoco belt crude oil since 1980. Most of the chapters focus on the methods rather than the resulting data on Cerro Negro oil, and results from other oils obtained during the verification of the method are included. In addition, published work on analysis of heavy oils, tar sand bitumens, and like materials is reviewed, and the overall state of the art in analytical methodology for heavy fossil liquids is assessed. The various phases of the work included: distillation and determination of routine'' physical/chemical properties (Chapter 1); preliminary separation of >200{degree}C distillates and the residue into acid, base, neutral, saturated hydrocarbon and neutral-aromatic concentrates (Chapter 2); further separation of acid, base, and neutral concentrates into subtypes (Chapters 3-5); and determination of the distribution of metal-containing compounds in all fractions (Chapter 6).

  16. Analysis of heavy oils: Method development and application to Cerro Negro heavy petroleum

    Energy Technology Data Exchange (ETDEWEB)

    None

    1989-12-01

    On March 6, 1980, the US Department of Energy (DOE) and the Ministry of Energy and Mines of Venezuela (MEMV) entered into a joint agreement which included analysis of heavy crude oils from the Venezuelan Orinoco oil belt. The purpose of this report is to present compositional data and describe new analytical methods obtained from work on the Cerro Negro Orinoco belt crude oil since 1980. Most of the chapters focus on the methods rather than the resulting data on Cerro Negro oil, and results from other oils obtained during the verification of the method are included. In addition, published work on analysis of heavy oils, tar sand bitumens, and like materials is reviewed, and the overall state of the art in analytical methodology for heavy fossil liquids is assessed. The various phases of the work included: distillation and determination of routine'' physical/chemical properties (Chapter 1); preliminary separation of >200{degrees} C distillates and the residue into acid, base, neutral, saturated hydrocarbon and neutral-aromatic concentrates (Chapter 2); further separation of acid, base, and neutral concentrates into subtypes (Chapters 3--5); and determination of the distribution of metal-containing compounds in all fractions (Chapter 6).

  17. [Analysis of trace elements in chrysanthemum from different habitats with ICP-MS].

    Science.gov (United States)

    Nie, Jiu-Sheng; Zhai, Hong-Yan; Wu, De-Ling; Zhang, Ya-Zhong; Fang, Cheng-Wu; Yu, Nian-Jun

    2013-03-01

    To establish a method for determination of trace elements in chrysanthemum and analyze trace elements in chrysanthemum from different habitats. The preprocessing for determination of trace elements in chrysanthemum was carried out by microwave digestion,the content of trace elements in chrysanthemum was determined by ICP-MS. The content of trace elements of chryscmthemum varied with the habitats. The contents of trace elements as well as heavy metals of Chrysanthemum relate to its species and habitats to a certain degree.

  18. 3-loop heavy flavor corrections in deep-inelastic scattering with two heavy quark lines

    Energy Technology Data Exchange (ETDEWEB)

    Ablinger, J.; Schneider, C. [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation; Bluemlein, J.; Freitas, A. de [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Hasselhuhn, A.; Round, M. [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Manteuffel, A. von [Mainz Univ. (Germany). Inst. fuer Physik; Wissbrock, F. [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Institut des Hautes Etudes Scientifiques, Bures-sur-Yvette (France)

    2014-07-15

    We consider gluonic contributions to the heavy flavor Wilson coefficients at 3-loop order in QCD with two heavy quark lines in the asymptotic region Q{sup 2} >> m{sup 2}{sub 1(2)}. Here we report on the complete result in the case of two equal masses m{sub 1}=m{sub 2} for the massive operator matrix element A{sup (3)}{sub gg,Q}, which contributes to the corresponding heavy flavor transition matrix element in the variable flavor number scheme. Nested finite binomial sums and iterated integrals over square-root valued alphabets emerge in the result for this quantity in N and x-space, respectively. We also present results for the case of two unequal masses for the flavor non-singlet OMEs and on the scalar integrals ic case of A{sup (3)}{sub gg,Q}, which were calculated without a further approximation. The graphs can be expressed by finite nested binomial sums over generalized harmonic sums, the alphabet of which contains rational letters in the ratio η=m{sup 2}{sub 1}/m{sup 2}{sub 2}.

  19. Toxicity of heavy metals to bromeliads and orchids in greenhouse cultures

    Energy Technology Data Exchange (ETDEWEB)

    Irmer, U.; Poppendiek, H.H.; Zechmeister, A.; Lorch, D.W.

    1982-01-01

    Symptoms of heavy metal toxicity were observed in greenhouse cultures of bromeliads and orchids. Samples of water, plants and substrate were analysed. The concentrations of zinc, cadmium, and lead were determined by atomic absorption spectroscopy. In all plants high concentration of zinc, cadmium, and lead were observed. The source of these heavy metals was found in the zinc-coated structural elements of the greenhouse from which acid rains extracted the heavy metals. The rainwater collected was used for watering the cultures and caused the symptoms of toxicity. Differences in the accumulation of heavy metals by the species examined are discussed.

  20. PHENIX recent heavy flavor results

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sanghoon

    2014-06-15

    Cold nuclear matter (CNM) effects provide an important ingredient to interpret the results from heavy-ion collisions. Such effects include nuclear shadowing, intrinsic parton transverse momentum broadening, and initial patron energy loss. The measurement of heavy quark production is a good probe to study the CNM effects particularly on gluons, since heavy quarks are mainly produced via gluon fusions at RHIC energy. The PHENIX experiment has an ability to study the CNM effects by measuring leptons from heavy-flavor decay in a broad kinematic range. Comparisons of the results measured in different rapidity regions allow us to study modification of gluon density function in the Au nucleus depending on parton fractional momentum x. In addition, comparisons to the results from heavy-ion collisions (Au + Au and Cu + Cu) measured by PHENIX provide an insight into the role of CNM effects in such collisions. Recent PHENIX results on heavy quark production are discussed in this presentation.

  1. Rotary drum separator system

    Science.gov (United States)

    Barone, Michael R. (Inventor); Murdoch, Karen (Inventor); Scull, Timothy D. (Inventor); Fort, James H. (Inventor)

    2009-01-01

    A rotary phase separator system generally includes a step-shaped rotary drum separator (RDS) and a motor assembly. The aspect ratio of the stepped drum minimizes power for both the accumulating and pumping functions. The accumulator section of the RDS has a relatively small diameter to minimize power losses within an axial length to define significant volume for accumulation. The pumping section of the RDS has a larger diameter to increase pumping head but has a shorter axial length to minimize power losses. The motor assembly drives the RDS at a low speed for separating and accumulating and a higher speed for pumping.

  2. The 3D structure of the immunoglobulin heavy-chain locus: implications for long-range genomic interactions.

    Science.gov (United States)

    Jhunjhunwala, Suchit; van Zelm, Menno C; Peak, Mandy M; Cutchin, Steve; Riblet, Roy; van Dongen, Jacques J M; Grosveld, Frank G; Knoch, Tobias A; Murre, Cornelis

    2008-04-18

    The immunoglobulin heavy-chain (Igh) locus is organized into distinct regions that contain multiple variable (V(H)), diversity (D(H)), joining (J(H)) and constant (C(H)) coding elements. How the Igh locus is structured in 3D space is unknown. To probe the topography of the Igh locus, spatial distance distributions were determined between 12 genomic markers that span the entire Igh locus. Comparison of the distance distributions to computer simulations of alternative chromatin arrangements predicted that the Igh locus is organized into compartments containing clusters of loops separated by linkers. Trilateration and triple-point angle measurements indicated the mean relative 3D positions of the V(H), D(H), J(H), and C(H) elements, showed compartmentalization and striking conformational changes involving V(H) and D(H)-J(H) elements during early B cell development. In pro-B cells, the entire repertoire of V(H) regions (2 Mbp) appeared to have merged and juxtaposed to the D(H) elements, mechanistically permitting long-range genomic interactions to occur with relatively high frequency.

  3. Biomedical Implications of Heavy Metals Induced Imbalances in Redox Systems

    Directory of Open Access Journals (Sweden)

    Bechan Sharma

    2014-01-01

    Full Text Available Several workers have extensively worked out the metal induced toxicity and have reported the toxic and carcinogenic effects of metals in human and animals. It is well known that these metals play a crucial role in facilitating normal biological functions of cells as well. One of the major mechanisms associated with heavy metal toxicity has been attributed to generation of reactive oxygen and nitrogen species, which develops imbalance between the prooxidant elements and the antioxidants (reducing elements in the body. In this process, a shift to the former is termed as oxidative stress. The oxidative stress mediated toxicity of heavy metals involves damage primarily to liver (hepatotoxicity, central nervous system (neurotoxicity, DNA (genotoxicity, and kidney (nephrotoxicity in animals and humans. Heavy metals are reported to impact signaling cascade and associated factors leading to apoptosis. The present review illustrates an account of the current knowledge about the effects of heavy metals (mainly arsenic, lead, mercury, and cadmium induced oxidative stress as well as the possible remedies of metal(s toxicity through natural/synthetic antioxidants, which may render their effects by reducing the concentration of toxic metal(s. This paper primarily concerns the clinicopathological and biomedical implications of heavy metals induced oxidative stress and their toxicity management in mammals.

  4. Biomedical implications of heavy metals induced imbalances in redox systems.

    Science.gov (United States)

    Sharma, Bechan; Singh, Shweta; Siddiqi, Nikhat J

    2014-01-01

    Several workers have extensively worked out the metal induced toxicity and have reported the toxic and carcinogenic effects of metals in human and animals. It is well known that these metals play a crucial role in facilitating normal biological functions of cells as well. One of the major mechanisms associated with heavy metal toxicity has been attributed to generation of reactive oxygen and nitrogen species, which develops imbalance between the prooxidant elements and the antioxidants (reducing elements) in the body. In this process, a shift to the former is termed as oxidative stress. The oxidative stress mediated toxicity of heavy metals involves damage primarily to liver (hepatotoxicity), central nervous system (neurotoxicity), DNA (genotoxicity), and kidney (nephrotoxicity) in animals and humans. Heavy metals are reported to impact signaling cascade and associated factors leading to apoptosis. The present review illustrates an account of the current knowledge about the effects of heavy metals (mainly arsenic, lead, mercury, and cadmium) induced oxidative stress as well as the possible remedies of metal(s) toxicity through natural/synthetic antioxidants, which may render their effects by reducing the concentration of toxic metal(s). This paper primarily concerns the clinicopathological and biomedical implications of heavy metals induced oxidative stress and their toxicity management in mammals.

  5. Biomedical Implications of Heavy Metals Induced Imbalances in Redox Systems

    Science.gov (United States)

    Singh, Shweta; Siddiqi, Nikhat J.

    2014-01-01

    Several workers have extensively worked out the metal induced toxicity and have reported the toxic and carcinogenic effects of metals in human and animals. It is well known that these metals play a crucial role in facilitating normal biological functions of cells as well. One of the major mechanisms associated with heavy metal toxicity has been attributed to generation of reactive oxygen and nitrogen species, which develops imbalance between the prooxidant elements and the antioxidants (reducing elements) in the body. In this process, a shift to the former is termed as oxidative stress. The oxidative stress mediated toxicity of heavy metals involves damage primarily to liver (hepatotoxicity), central nervous system (neurotoxicity), DNA (genotoxicity), and kidney (nephrotoxicity) in animals and humans. Heavy metals are reported to impact signaling cascade and associated factors leading to apoptosis. The present review illustrates an account of the current knowledge about the effects of heavy metals (mainly arsenic, lead, mercury, and cadmium) induced oxidative stress as well as the possible remedies of metal(s) toxicity through natural/synthetic antioxidants, which may render their effects by reducing the concentration of toxic metal(s). This paper primarily concerns the clinicopathological and biomedical implications of heavy metals induced oxidative stress and their toxicity management in mammals. PMID:25184144

  6. 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) .

  7. Distribution of Heavy Metal Pb

    OpenAIRE

    Samawi, Muh. Farid; Tambaru, Rahmadi; Husain, Aida Ala; Burhanuddin, Andi Iqbal

    2014-01-01

    Distribution of Heavy Metal Pb in Benthic Organism and Sediment Bonebatang Island Waters Benthic organisms Bonebatang Island waters consist of branching hard corals, massive hard corals, soft corals, sponges, macroalgae, coralline algae, seagrass and mussels have the potential to accumulate heavy metals Pb from the water column. Results of studies have determined the rate of accumulation of heavy metals Pb some benthic organisms in the Bonebatang Island waters. Branching hard corals have a...

  8. Heavy quark production and spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Appel, J.A.

    1993-11-01

    This review covers many new experimental results on heavy flavor production and spectroscopy. It also shows some of the increasingly improved theoretical understanding of results in light of basic perturbative QCD and heavy quark symmetry. At the same time, there are some remaining discrepancies among experiments as well as significant missing information on some of the anticipated lowest lying heavy quark states. Most interesting, perhaps, are some clearly measured production effects awaiting full explanation.

  9. Heavy ion therapy: Bevalac epoch

    Energy Technology Data Exchange (ETDEWEB)

    Castro, J.R.

    1993-10-01

    An overview of heavy ion therapy at the Bevelac complex (SuperHILac linear accelerator + Bevatron) is given. Treatment planning, clinical results with helium ions on the skull base and uveal melanoma, clinical results with high-LET charged particles, neon radiotherapy of prostate cancer, heavy charged particle irradiation for unfavorable soft tissue sarcoma, preliminary results in heavy charged particle irradiation of bone sarcoma, and irradiation of bile duct carcinoma with charged particles and-or photons are all covered. (GHH)

  10. Mars Atmospheric Capture and Gas Separation

    Science.gov (United States)

    Muscatello, Anthony; Santiago-Maldonado, Edgardo; Gibson, Tracy; Devor, Robert; Captain, James

    2011-01-01

    The Mars atmospheric capture and gas separation project is selecting, developing, and demonstrating techniques to capture and purify Martian atmospheric gases for their utilization for the production of hydrocarbons, oxygen, and water in ISRU systems. Trace gases will be required to be separated from Martian atmospheric gases to provide pure C02 to processing elements. In addition, other Martian gases, such as nitrogen and argon, occur in concentrations high enough to be useful as buffer gas and should be captured as welL To achieve these goals, highly efficient gas separation processes will be required. These gas separation techniques are also required across various areas within the ISRU project to support various consumable production processes. The development of innovative gas separation techniques will evaluate the current state-of-the-art for the gas separation required, with the objective to demonstrate and develop light-weight, low-power methods for gas separation. Gas separation requirements include, but are not limited to the selective separation of: (1) methane and water from un-reacted carbon oxides (C02- CO) and hydrogen typical of a Sabatier-type process, (2) carbon oxides and water from unreacted hydrogen from a Reverse Water-Gas Shift process, (3) carbon oxides from oxygen from a trash/waste processing reaction, and (4) helium from hydrogen or oxygen from a propellant scavenging process. Potential technologies for the separations include freezers, selective membranes, selective solvents, polymeric sorbents, zeolites, and new technologies. This paper and presentation will summarize the results of an extensive literature review and laboratory evaluations of candidate technologies for the capture and separation of C02 and other relevant gases.

  11. Heavy-Quark Fragmentation

    CERN Document Server

    Cacciari, M; Cacciari, Matteo; Gardi, Einan

    2003-01-01

    We study perturbative and non-perturbative aspects of heavy-quark fragmentation into hadrons, emphasizing the large-x region, where x is the energy fraction of the detected hadron. We first prove that when the moment index N and the quark mass m get large simultaneously with the ratio (N Lambda/m) fixed, the fragmentation function depends on this ratio alone. This opens up the way to formulate the non-perturbative contribution to the fragmentation function at large N as a shape function of m(1-x) which is convoluted with the Sudakov-resummed perturbative result. We implement this resummation and the parametrization of the corresponding shape function using Dressed Gluon Exponentiation. The Sudakov exponent is calculated in a process independent way from a generalized splitting function which describes the emission probability of an off-shell gluon off a heavy quark. Non-perturbative corrections are parametrized based on the renormalon structure of the Sudakov exponent. They appear in moment space as an expone...

  12. Ultrarelativistic heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Pugh, H.G.

    1980-12-01

    Studies with ultrarelativistic heavy ions combine aspects of cosmic ray physics, particle physics, nuclear physics, astrophysics and cosmogenesis. The leading theoretical concerns are the behavior of matter at very high-energy density and flux, the general behavior of space time in collisions, relativistic nuclear theory, and quantum chromodynamics. The field has developed over a period of more than thirty years, since the first observation of heavy nuclei in cosmic rays and the major developments of understanding of high-energy collisions made by Fermi and Landau in the early fifties. In the late sixties the discovery of the parton content of nucleons was rapidly followed by a great extension of high-energy collision phenomenology at the CERN ISR and subsequent confirmation of the QCD theory. In parallel the study of p-nucleus and nucleus-nucleus collisions at very high energies, especially at the CERN PS, Fermilab and the Bevalac, and in cosmic rays demonstrated that studies involving the nucleus opened up a new dimension in studies of the hadronic interaction. It is now at a high level of interest on an international scale, with major new accelerators being proposed to dedicate to this kind of study.

  13. Geostatistical exploration of dataset assessing the heavy metal contamination in Ewekoro limestone, Southwestern Nigeria

    Directory of Open Access Journals (Sweden)

    Kehinde D. Oyeyemi

    2017-10-01

    Full Text Available The dataset for this article contains geostatistical analysis of heavy metals contamination from limestone samples collected from Ewekoro Formation in the eastern Dahomey basin, Ogun State Nigeria. The samples were manually collected and analysed using Microwave Plasma Atomic Absorption Spectrometer (MPAS. Analysis of the twenty different samples showed different levels of heavy metals concentration. The analysed nine elements are Arsenic, Mercury, Cadmium, Cobalt, Chromium, Nickel, Lead, Vanadium and Zinc. Descriptive statistics was used to explore the heavy metal concentrations individually. Pearson, Kendall tau and Spearman rho correlation coefficients was used to establish the relationships among the elements and the analysis of variance showed that there is a significant difference in the mean distribution of the heavy metals concentration within and between the groups of the 20 samples analysed. The dataset can provide insights into the health implications of the contaminants especially when the mean concentration levels of the heavy metals are compared with recommended regulatory limit concentration.

  14. Radiochemical separation of Cobalt

    NARCIS (Netherlands)

    Erkelens, P.C. van

    1961-01-01

    A method is described for the radiochemical separation of cobalt based on the extraordinary stability of cobalt diethyldithiocarbamate. Interferences are few; only very small amounts of zinc and iron accompany cobalt, which is important in neutron-activation analysis.

  15. Separation Anxiety (For Parents)

    Science.gov (United States)

    ... older child, there might be another problem, like bullying or abuse. Separation anxiety is different from the normal feelings older kids have when they don't want a parent to leave (which can usually be overcome if ...

  16. Separation by solvent extraction

    Science.gov (United States)

    Holt, Jr., Charles H.

    1976-04-06

    17. A process for separating fission product values from uranium and plutonium values contained in an aqueous solution, comprising adding an oxidizing agent to said solution to secure uranium and plutonium in their hexavalent state; contacting said aqueous solution with a substantially water-immiscible organic solvent while agitating and maintaining the temperature at from -1.degree. to -2.degree. C. until the major part of the water present is frozen; continuously separating a solid ice phase as it is formed; separating a remaining aqueous liquid phase containing fission product values and a solvent phase containing plutonium and uranium values from each other; melting at least the last obtained part of said ice phase and adding it to said separated liquid phase; and treating the resulting liquid with a new supply of solvent whereby it is practically depleted of uranium and plutonium.

  17. Separable Arrowhead Microneedles

    Science.gov (United States)

    Chu, Leonard Y.; Prausnitz, Mark R.

    2010-01-01

    Hypodermic needles cause pain and bleeding, produce biohazardous sharp waste and require trained personnel. To address these issues, we introduce separable arrowhead microneedles that rapidly and painlessly deliver drugs and vaccines to the skin. These needles are featured by micron-size sharp tips mounted on blunt shafts. Upon insertion in the skin, the sharp-tipped polymer arrowheads encapsulating drug separate from their metal shafts and remain embedded in the skin for subsequent dissolution and drug release. The blunt metal shafts can then be discarded. Due to rapid separation of the arrowhead tips from the shafts within seconds, administration using arrowhead microneedles can be carried out rapidly, while drug release kinetics can be independently controlled based on separable arrowhead formulation. Thus, drug and vaccine delivery using arrowhead microneedles are designed to offer a quick, convenient, safe and potentially self-administered method of drug delivery as an alternative to hypodermic needles. PMID:21047538

  18. Heavy oils processing materials requirements crude processing

    Energy Technology Data Exchange (ETDEWEB)

    Sloley, Andrew W. [CH2M Hill, Englewood, CO (United States)

    2012-07-01

    Over time, recommended best practices for crude unit materials selection have evolved to accommodate new operating requirements, feed qualities, and product qualities. The shift to heavier oil processing is one of the major changes in crude feed quality occurring over the last 20 years. The three major types of crude unit corrosion include sulfidation attack, naphthenic acid attack, and corrosion resulting from hydrolyzable chlorides. Heavy oils processing makes all three areas worse. Heavy oils have higher sulfur content; higher naphthenic acid content; and are more difficult to desalt, leading to higher chloride corrosion rates. Materials selection involves two major criteria, meeting required safety standards, and optimizing economics of the overall plant. Proper materials selection is only one component of a plant integrity approach. Materials selection cannot eliminate all corrosion. Proper materials selection requires appropriate support from other elements of an integrity protection program. The elements of integrity preservation include: materials selection (type and corrosion allowance); management limits on operating conditions allowed; feed quality control; chemical additives for corrosion reduction; and preventive maintenance and inspection (PMI). The following discussion must be taken in the context of the application of required supporting work in all the other areas. Within that context, specific materials recommendations are made to minimize corrosion due to the most common causes in the crude unit. (author)

  19. Hydrogen separation process

    Science.gov (United States)

    Mundschau, Michael [Longmont, CO; Xie, Xiaobing [Foster City, CA; Evenson, IV, Carl; Grimmer, Paul [Longmont, CO; Wright, Harold [Longmont, CO

    2011-05-24

    A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200.degree. C., to a hydrogen separation membrane system comprising a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200.degree. C., to an integrated water gas shift/hydrogen separation membrane system wherein the hydrogen separation membrane system comprises a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for pretreating a membrane, comprising: heating the membrane to a desired operating temperature and desired feed pressure in a flow of inert gas for a sufficient time to cause the membrane to mechanically deform; decreasing the feed pressure to approximately ambient pressure; and optionally, flowing an oxidizing agent across the membrane before, during, or after deformation of the membrane. A method of supporting a hydrogen separation membrane system comprising selecting a hydrogen separation membrane system comprising one or more catalyst outer layers deposited on a hydrogen transport membrane layer and sealing the hydrogen separation membrane system to a porous support.

  20. Heavy metal sensitivity and bioconcentration in oribatid mites (Acari, Oribatida)

    Energy Technology Data Exchange (ETDEWEB)

    Skubala, Piotr, E-mail: piotr.skubala@us.edu.pl [Department of Ecology, University of Silesia, Bankowa 9, 40-007 Katowice (Poland); Zaleski, Tomasz [Department of Soil Science and Soil Protection, Agricultural University in Krakow, Mickiewicza 21, 31-120 Cracow (Poland)

    2012-01-01

    In this study we aimed to identify different reactions of oribatid species to heavy metal pollution and to measure concentrations of cadmium, zinc and copper in oribatid species sampled along a gradient. Oribatid mites were sampled seasonally during two years in five meadows located at different distances from the zinc smelter in the Olkusz District, southern Poland. Oribatids were shown to withstand critical metal concentration and established comparatively abundant and diverse communities. The highest abundance and species richness of oribatids were recorded in soils with moderate concentrations of heavy metals. Four different responses of oribatid species to heavy metal pollution were recognized. Heavy metals (Zn, Pb, Cd, Ni) and various physical (bulk density, field capacity, total porosity) and chemical (K{sub av}, P{sub av}, N, C, pH) factors were recognized as the structuring forces that influence the distribution of oribatid species. Analysis by atomic absorption spectrophotometry revealed large differences in metal body burdens among species. None of the species can be categorized as accumulators or non-accumulators of the heavy metals - the pattern depends on the metal. The process of bioconcentration of the toxic metal (regulated) and essential elements (accumulated) was generally different in the five oribatid species studied. - Highlights: Black-Right-Pointing-Pointer Responses of oribatid mites to metal contamination along a gradient in meadow soils were studied. Black-Right-Pointing-Pointer Small concentrations of heavy metals positively influenced the abundance of oribatid mites. Black-Right-Pointing-Pointer Four different responses of oribatid species to heavy metal pollution were recognised. Black-Right-Pointing-Pointer Bioaccumulation of the toxic metal and essential elements proceeded differently in oribatid species. Black-Right-Pointing-Pointer Five studied oribatid species were deconcentrators of cadmium.

  1. 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.)

  2. Preventing oil adhesion to pipe walls in heavy crude transportation

    Energy Technology Data Exchange (ETDEWEB)

    Rivero, M.; Guevara, E.; Joseph, D. [and others

    1995-12-31

    During the transportation of heavy, extra heavy, and bitumen with water in carbon steel pipelines, the crude sticks to the internal pipe wall, reducing the flow area and as a consequence increasing the pressure drop in time. The situation may become worse if an unplanned shut down occurs, due to the phase separation by gravity. The problem. is resolved using a cement lined pipeline, with a cement composition that creates a permanent oleophobic and hydrophilic surface. These surfaces repel oil when they are hydrated in water, avoiding the occurrence of fouling at stationary and restart conditions.

  3. New elements - approaching Z=114

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, S.

    1998-03-01

    The search for new elements is part of the broader field of investigations of nuclei at the limits of stability. In two series of experiments at SHIP, six new elements (Z=107-112) were synthesized via fusion reactions using 1n-deexcitation channels and lead or bismuth targets. The isotopes were unambiguously identified by means of {alpha}-{alpha} correlations. Not fission, but alpha decay is the dominant decay mode. The collected decay data establish a means of comparison with theoretical data. This aids in the selection of appropriate models that describe the properties of known nuclei. Predictions based on these models are useful in the preparation of the next generation of experiments. Cross-sections decrease by two orders of magnitude from bohrium (Z=107) to element 112, for which a cross-section of 1 pb was measured. The development of intense beam currents and sensitive detection methods is essential for the production and identification of still heavier elements and new isotopes of already known elements, as well as the measurement of small {alpha}-, {beta}- and fission-branching ratios. An equally sensitive set-up is needed for the measurement of excitation functions at low cross-sections. Based on our results, it is likely that the production of isotopes of element 114 close to the island of spherical super heavy elements (SHE) could be achieved by fusion reactions using {sup 208}Pb targets. Systematic studies of the reaction cross-sections indicate that the transfer of nucleons is an important process for the initiation of fusion. The data allow for the fixing of a narrow energy window for the production of SHE using 1n-emission channels. (orig.)

  4. Data acquisition for the HILI (Heavy Ion Light Ion) detector

    Energy Technology Data Exchange (ETDEWEB)

    Teh, K.M.; Shapira, D.; McConnell, J.W.; Kim, H.; Novotny, R.

    1987-01-01

    A large acceptance, multi-segmented detector system capable of the simultaneous detection of heavy and light ions has been constructed. The heavy ions are detected with a segmented gas ionization chamber and a multiwire proportional counter while the light ions are detected with a 192 element plastic phoswich hodoscope. Processing the large number of signals is accomplished through a combination of CAMAC and FASTBUS modules and preprocessors, and a Host minicomputer. Details of the data acquisition system and the reasons for adopting a dual standards system are discussed. In addition, a technique for processing signals from an individual hodoscope detector is presented. 4 refs., 3 figs.

  5. Fluid clathrate system for continuous removal of heavy noble gases from mixtures of lighter gases

    Science.gov (United States)

    Gross, Kenneth C.; Markun, Francis; Zawadzki, Mary T.

    1998-01-01

    An apparatus and method for separation of heavy noble gas in a gas volume. An apparatus and method have been devised which includes a reservoir containing an oil exhibiting a clathrate effect for heavy noble gases with a reservoir input port and the reservoir is designed to enable the input gas volume to bubble through the oil with the heavy noble gas being absorbed by the oil exhibiting a clathrate effect. The gas having reduced amounts of heavy noble gas is output from the oil reservoir, and the oil having absorbed heavy noble gas can be treated by mechanical agitation and/or heating to desorb the heavy noble gas for analysis and/or containment and allow recycling of the oil to the reservoir.

  6. Technology management for heavy oil

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, R. [Wascana Energy Inc., Regina, AB (Canada)

    1994-12-31

    The framework for investment in research and development (R&D) at a medium-sized Canadian petroleum company is described. The importance of R&D is illustrated by a graph showing the strong positive correlation between R&D intensity and sales for companies in the mainstream oil and gas sector in the USA. Strong R&D efforts also help to maintain market share and enhance corporate ability to transfer technology into its operations. Three ways of structuring, developing, and transferring technology are outlined: using in-house R&D facilities, which is too costly for medium-sized firms; having a central group responsible for funding third-party R&D, transferring technology into the company, and being aware of technology activities within and outside the company; and complete decentralizing of R&D, in which operations decides how, when, and what to spend on R&D. For the medium-sized company, the second option is considered the best choice. Essential R&D administration practices for such a company are reviewed, including corporate support, an updated technology strategy, central funding with a separate budget from operations, a portfolio of R&D projects and ideas, collaboration with other organizations, and effective communication of R&D activity and results to the company. At the company studied, Wascana Energy, R&D is being focused on three priority areas: production technology, enhanced recovery, and heavy oil upgrading. It is estimated that the monetary benefits of R&D in these three areas could be as much as $100 million. The evaluation of R&D performance is then discussed and critical factors for R&D success are listed. 3 figs., 1 tab.

  7. LEXUS heavy ion collisions

    CERN Document Server

    Sang Yong Jeon

    1997-01-01

    We use a Glauber-like approach to describe very energetic nucleus- nucleus collisions as a sequence of binary nucleon-nucleon collisions. No free parameters are needed: all the information comes from simple parametrizations of nucleon-nucleon collision data. Produced mesons are assumed not to interact with each other or with the original baryons. Comparisons are made to published experimental measurements of baryon rapidity and transverse momentum distributions, negative hadron rapidity and transverse momentum distributions, average multiplicities of pions, kaons, hyperons, and antihyperons, and zero degree energy distributions for sulfur-sulfur collisions at 200 GeV/c per nucleon and for lead-lead collisions at 158 GeV/c per nucleon. Good agreement is found except that the number of strange particles produced, especially antihyperons, is too small compared with experiment. We call this model LEXUS: Linear EXtrapolation of Ultrarelativistic nucleon-nucleon Scattering to heavy ion collisions. (11 refs).

  8. Elements of spatial data quality

    CERN Document Server

    Guptill, SC

    1995-01-01

    Elements of Spatial Data Quality outlines the need and suggests potential categories for the content of a comprehensive statement of data quality that must be imbedded in the metadata that accompanies the transfer of a digital spatial data file or is available in a separate metadata catalog. Members of the International Cartographic Association's Commission on Spatial Data Quality have identified seven elements of data quality: positional accuracy, attribute accuracy, completeness, logical consistency, lineage, semantic accuracy and temporal information. In the book the authors describe: compo

  9. Gulf stream separation dynamics

    Science.gov (United States)

    Schoonover, Joseph

    Climate models currently struggle with the more traditional, coarse ( O(100 km) ) representation of the ocean. In these coarse ocean simulations, western boundary currents are notoriously difficult to model accurately. The modeled Gulf Stream is typically seen exhibiting a mean pathway that is north of observations, and is linked to a warm sea-surface temperature bias in the Mid-Atlantic Bight. Although increased resolution ( O(10 km) ) improves the modeled Gulf Stream position, there is no clean recipe for obtaining the proper pathway. The 70 year history of literature on the Gulf Stream separation suggests that we have not reached a resolution on the dynamics that control the current's pathway just south of the Mid-Atlantic Bight. Without a concrete knowledge on the separation dynamics, we cannot provide a clean recipe for accurately modeling the Gulf Stream at increased resolutions. Further, any reliable parameterization that yields a realistic Gulf Stream path must express the proper physics of separation. The goal of this dissertation is to determine what controls the Gulf Stream separation. To do so, we examine the results of a model intercomparison study and a set of numerical regional terraforming experiments. It is argued that the separation is governed by local dynamics that are most sensitive to the steepening of the continental shelf, consistent with the topographic wave arrest hypothesis of Stern (1998). A linear extension of Stern's theory is provided, which illustrates that wave arrest is possible for a continuously stratified fluid.

  10. Heavy flavor results from CMS

    CERN Document Server

    Ronchese, Paolo

    2017-01-01

    Heavy flavor particles produced in LHC $pp$ collisions at $7, 8,$ and $13~\\mathrm{TeV}$ constitute an excellent opportunity to test the standard model and probe for new physics effects. Recent results by the CMS Collaboration on heavy flavor production and decays are presented.

  11. Heavy snowfall damage Virginia pine

    Science.gov (United States)

    Richard H. Fenton

    1959-01-01

    In the Coastal Plain from Virginia to Pennsylvania, snowstorms heavy enough to damage trees are unusual. Weather Bureau records for the general area show that heavy snowfall - 8 to 25 inches in a single storm - occurs at an average frequency of about once in 7 years.

  12. Heavy flavours: working group summary

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Ahmed [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Gladilin, Leonid [Moscow State Univ. (Russian Federation). Scobeltsyn Inst. of Nuclear Physics; Tonelli, Diego [Fermi National Accelerator Lab., Batavia, IL (United States)

    2009-07-15

    The talks presented in the working group ''Heavy flavours'' of the DIS 2009 workshop are summarised. New and recently updated results from theory, proton antiproton and heavy ion colliders, as well from HERA and e{sup +}e{sup -} colliders are discussed. (orig.)

  13. Heavy hadrons in nuclear matter

    Science.gov (United States)

    Hosaka, Atsushi; Hyodo, Tetsuo; Sudoh, Kazutaka; Yamaguchi, Yasuhiro; Yasui, Shigehiro

    2017-09-01

    Current studies on heavy hadrons in nuclear medium are reviewed with a summary of the basic theoretical concepts of QCD, namely chiral symmetry, heavy quark spin symmetry, and the effective Lagrangian approach. The nuclear matter is an interesting place to study the properties of heavy hadrons from many different points of view. We emphasize the importance of the following topics: (i) charm/bottom hadron-nucleon interaction, (ii) structure of charm/bottom nuclei, and (iii) QCD vacuum properties and hadron modifications in nuclear medium. We pick up three different groups of heavy hadrons, quarkonia (J / ψ, ϒ), heavy-light mesons (D/ D ¯ , B ¯ / B) and heavy baryons (Λc, Λb). The modifications of those hadrons in nuclear matter provide us with important information to investigate the essential properties of heavy hadrons. We also give the discussions about the heavy hadrons, not only in infinite nuclear matter, but also in finite-size atomic nuclei with finite baryon numbers, to serve future experiments.

  14. Mycodiversity in marine sediments contaminated by heavy metals: preliminary results

    Science.gov (United States)

    Zotti, Mirca; Carbone, Cristina; Cecchi, Grazia; Consani, Sirio; Cutroneo, Laura; Di Piazza, Simone; Gabutto, Giacomo; Greco, Giuseppe; Vagge, Greta; Capello, Marco

    2016-04-01

    Fungi represent the main decomposers of woody and herbaceous substrates in the marine ecosystems. To date there is a gap in the knowledge about the global diversity and distribution of fungi in marine habitats. On the basis of their biological diversity and their role in ecosystem processes, marine fungi may be considered one of the most attractive groups of organisms in modern biotechnology, e.g. ecotoxic metal bioaccumulation. Here we report the data about the first mycological survey in the metal contaminated coastal sediments of the Gromolo Bay. The latter is located in Ligurian Sea (Eastern Liguria, Italy) and is characterized by an enrichment of heavy metals due to pollution of Gromolo Torrent by acidic processes that interest Fe-Cu sulphide mine. 24 samples of marine sediments were collected along a linear plot in front of the shoreline in July 2015. Each sample was separated into three aliquot for mineralogical, chemical analyses and fungal characterization. The sediment samples are characterised by clay fractions (illite and chlorite), minerals of ophiolitic rocks (mainly serpentine, pyroxene and plagioclase) and quartz and are enriched some chemical elements of environmental importance (such as Cu, Zn, Pb, Cd, As). For fungal characterisation the sediment samples were inoculated in Petri dishes on different culture media (Malt Extract Agar and Rose Bengal) prepared with sea water and added with antibiotics. The inoculated dishes were incubated at 20°C in the dark for 28 days. Every week fungal growth was monitored counting the number of colonies. Later, the colonies were isolated in axenic culture for further molecular analysis. The mycodiversity evaluate on the basis of Colony Forming Units (CFU) and microfungal-morphotype characterised by macro-and micro-morphology. Until now on the 72 Petri dishes inoculated 112 CFU of filamentous fungi were counted, among these about 50 morphotypes were characterized. The quantitative results show a mean value of 4

  15. Results of heavy ion radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Castro, J.R. [Lawrence Berkeley Lab., CA (United States). Life Sciences Div.

    1994-04-01

    The potential of heavy ion therapy for clinical use in cancer therapy stems from the biological parameters of heavy charged particles, and their precise dose localization. Biologically, carbon, neon and other heavy ion beams (up to about silicon) are clinically useful in overcoming the radioresistance of hypoxic tumors, thus increasing biological effectiveness relative to low-LET x-ray or electron beams. Cells irradiated by heavy ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical parameters of these heavy charged particles allow precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. Clinical use requires close interaction between radiation oncologists, medical physicists, accelerator physicists, engineers, computer scientists and radiation biologists.

  16. Mass Separation by Metamaterials

    Science.gov (United States)

    Restrepo-Flórez, Juan Manuel; Maldovan, Martin

    2016-02-01

    Being able to manipulate mass flow is critically important in a variety of physical processes in chemical and biomolecular science. For example, separation and catalytic systems, which requires precise control of mass diffusion, are crucial in the manufacturing of chemicals, crystal growth of semiconductors, waste recovery of biological solutes or chemicals, and production of artificial kidneys. Coordinate transformations and metamaterials are powerful methods to achieve precise manipulation of molecular diffusion. Here, we introduce a novel approach to obtain mass separation based on metamaterials that can sort chemical and biomolecular species by cloaking one compound while concentrating the other. A design strategy to realize such metamaterial using homogeneous isotropic materials is proposed. We present a practical case where a mixture of oxygen and nitrogen is manipulated using a metamaterial that cloaks nitrogen and concentrates oxygen. This work lays the foundation for molecular mass separation in biophysical and chemical systems through metamaterial devices.

  17. Framed primal elements

    OpenAIRE

    Debongnie, Jean-François

    1986-01-01

    Framed primal finite elements may be viewed as a generalized class of elements including conforming elements, primal hybrids, and non concorming elements passing the patch test. This systematization is illustrated on a lot of examples.

  18. Occurrence and distribution of selected heavy metals in the surface sediments of South Brittany coastal waters: An assessment using pollution indicators

    Science.gov (United States)

    Ong, M. C.; Menier, D.; Noor Azhar, M. S.; Dupont, V.; Révillon, S.

    2012-04-01

    In order to avoid the pollution of heavy metals in South Brittany water, it is necessary to establish the data and understand the mechanisms influencing the distribution of heavy metals of the area. One of the aims of this work was to assess heavy metals contamination in Gulf of Morbihan and Quiberon Bay. Another aim was to use interpolation surfaces per metals to assess the contamination separately per metal. A total of 196 bottom sediment samples were collected from the coastal waters in order to determine the spatial concentration of Cr, Mn, Co, Cu, Zn, Cd and Pb by Inductively Coupled Plasma Mass Spectrometry (ICPMS) after acid digestion. The average heavy metal concentrations are ranked as follows: Mn>Zn>Cr>Pb>Cu>Cu>Cd. In the gulf, metal enrichments observed compared to the bay environment may due river run-off from three major river (Auray, Le Marle and Novalo rivers) which carried municipal waste and maritime activities along the coastal area within the gulf. Beside those factors, the natural factors such as the sheltered basin morphology itself, fine sediment and low hydrodynamic regime which favour the in situ accumulation of pollutants. The level of pollution levels attributed to heavy metals was evaluated using several pollution indicators in order to determine anthropogenically derived sediment contamination. Comparison to sediment quality guidelines (SQGs), enrichment factors (EFs), index of geoaccumulation (Igeo) and contamination factors (CF) based on reference element and background value to compensate for the influence of the natural variability in sediment mineralogy and to assess whether the concentration observed in surface sediment represent background and contaminated levels and visualize using ArcGIS software. These analyses validated that the bottom sediment only enriched in Pb and the other metals in most sample are not due to artificial contamination. Overall, geochemistry of the samples show the effect of both natural and anthropogenic

  19. Particle collection efficiency of the rotational particle separator

    NARCIS (Netherlands)

    Brouwers, J.J.H.

    1997-01-01

    The rotational particle separator is a patented technique for separating solid and/or liquid particles of 0.1 m and larger from gases. The core component is the rotating filter element which consists of a multitude of axially oriented channels which rotate as a whole around a common axis. Particles

  20. Family routines and rituals following separation: continuity and change

    NARCIS (Netherlands)

    Bakker, W.; Karsten, L.; Mulder, C.H.

    2015-01-01

    Separation always changes family life. The aim of this study is to gain insight into the everyday practices of ‘doing family’ after separation. We focus on two central elements of family life: routines and rituals. While in most families both parents are involved in family routines and rituals, this