WorldWideScience
1

Determination of Ca, Cr, Cu, Fe, K, Mg, Na and Zn in Brazilian medicinal plants by neutron activation and atomic absorption; Determinacao de Ca, Cr, Cu, Fe, K, Mg, Na e Zn em plantas medicinais brasileiras por ativacao neutronica e absorcao atomica  

Energy Technology Data Exchange (ETDEWEB)

Medicinal plants are available in the markets in Belo Horizonte, Minas Gerais. The objective of this work is to investigate the Ca, Cr, Cu, Fe, K, Mg, Na e Zn concentrations in two lots of usually known diuretics plants (azeitona do mato, cabelo de milho, cavalinha, cervejinha do campo, chapeu de couro, congonha de bugre, marmelinho do campo and quebra pedra) bought with an interval of time - six months - between the purchases. The elemental concentrations were determined applying k{sub 0} instrumental neutron activation analysis and atomic absorption spectrophotometry analysis. (author)

2002-07-01

5

EMS and evaluation of environmental aspects: a review  

International Nuclear Information System (INIS)

The Environmental Management System (EMS) is an instrument to manage the interaction between the organization and the environment. The scope od EMS is to reduce the environmental impact and to achieve improvements in overall performances. In particular, the focus point of EMS implementation is the method for identifying and assessing significant environmental aspects. This paper presents a review of methods and techniques existing in this area, and the definition of the state of the art. The results of the literature, regulation and case studies reviews have shown that rigorous, repeatable and transparent methodologies do not exist.

2006-04-01

8

Study of the inorganic constituents in different species of Casearia medicinal plant collected in distinct regions of the Atlantic Forest, SP State, Brazil; Estudo sobre os constituintes inorganicos presentes em diferentes especies da planta medicinal do genero Casearia coletadas em regioes distintas da Mata Atlantica, SP  

Energy Technology Data Exchange (ETDEWEB)

The use of medicinal plants in the treatment of diseases has increased significantly in the last years, as has research concerning chemical characterization of these plants. In this study, inorganic constituents were determined in leaves and in extracts from three medicinal plant species of the Casearia genus (C. sylvestris, C. decandra and C. obliqua) collected in distinct regions of the Atlantic Forest, SP. The elemental compositions of the soils in which these plants were grown were also determined. Traditionally, these plants are used due to their antiinflammatory, antiacid, antiseptic and cicatrizing properties. The antiulcer and the antitumor activities of the Casearia genus and its capacity to neutralize snake and bee venoms, have also been scientifically confirmed. The analytical methodology used was neutron activation analysis. Long and short irradiation periods of the samples and the standards were carried out at IPEN's IEA-R1 nuclear research reactor. In the leaf K ...

2006-07-01

10

Numerical field calculations considering the human subject for engineering and safety assurance in MRI  

UK PubMed Central (United Kingdom)

Numerical calculations of static, switched, and radiofrequency (RF) electromagnetic (EM) fields considering the geometry and EM properties of the human body are used increasingly in MRI to explain...Full Text Available

2009-11-01

14

Ultraviolet detectors based on ZnO films by thermal oxidation of Zn metallic films  

British Library Electronic Table of Contents (United Kingdom)

Metallic Zn films were deposited on glass substrates by electron-beam evaporation. ZnO films were synthesized by thermal oxidation of Zn metallic films in air. At the annealing temperature of 550 ?C, ZnO nanowires appeared on the surface, which mainly result from the decrease of oxidation rate. A ZnO ultraviolet photodetector was fabricated based on a metal-semiconductor-metal planar structure. The detector showed a large UV photoresponse with an increase of two orders of magnitude. It is concluded that promising UV detectors can be obtained on ZnO films by thermal oxidation of Zn metallic films. The ways of performing spectral response measurements for polycrystalline ZnO films are also discussed.

2008-01-01

15

The secondary slurry-zinc/air battery  

Energy Technology Data Exchange (ETDEWEB)

The rechargeability of the slurry-Zn/air battery was demonstrated with a practical recharge cell that requires minimal hydraulic and mechanical energy for operation. A dendritic Zn was deposited on a Mg plate substrate from which it was easily, periodically and automatically scraped to regenerate dendritic Zn slurries. Excellent discharge results were obtained with the regenerated dendritic Zn slurry, comparable to those obtained with slurries made with mixtures of Zn powder. The dendritic Zn slurry allowed, however, twice the utilization of Zn. 13 refs., 24 figs., 2 tabs.

1989-07-01

16

Integrating the Integrators - A Roadmap to Success  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy Environmental Management's (DOE-EM) investments in science and technology, as well as science and technology investments associated with other parts of the DOE are aimed at meeting the Departments cleanup goals. These investments, primarily focused on EM's cleanup mission, comprise the Environmental Quality Research and Development (R&D) portfolios. Synchronizing EM's Cleanup Project Managers (operations facility and process owners throughout the DOE complex) operational needs with EM R&D including the extensive work of the six Focus Areas (major thrust areas within DOE-EM) has been a continuing challenge. This recent initiative to better integrate the R&D program is in response to evolving needs within the Department to apply proven system engineering methods to clarify requirements and define ...

1999-03-01

17

Preparation and properties of poly(propylene carbonate) and nanosized ZnO composite films for packaging applications  

British Library Electronic Table of Contents (United Kingdom)

Abstract A series of polypropylene carbonate (PPC)/ZnO nanocomposite films with different ZnO contents were prepared via a solution blending method. The morphological structures, thermal properties, oxygen permeability, water sorption, and antibacterial properties of the films were investigated as a function of ZnO concentration. While all of the composite films with less than 5 wt % ZnO exhibited good dispersion of ZnO in the PPC matrix, FTIR and SEM results revealed that solution blending did not lead to a strong interaction between PPC and unmodified ZnO. As such, poor dispersion was induced in the composite films with a high ZnO content. By incorporating inorganic ZnO filler nanoparticles, the diffusion coefficient, water uptake in equilibrium, and oxygen permeability decreased as the ...

2011-01-01

18

Liver Zn-thionein (ZnMT) regulates the interaction of Zn and Pb with delta-aminolevulinic acid dehydratase (ALAD)  

Energy Technology Data Exchange (ETDEWEB)

ZnMT has been postulated to function in essential metal homeostasis and metal detoxication. This study was undertaken to evaluate the potential of liver ZnMT to mediate the interaction of Zn and Pb with the Zn metalloenzyme, ALAD. Pretreatment of rats with Zn activated liver ALAD and attenuated the inhibition of ALAD by Pb in vitro and in vivo. Liver cytosol from Zn-pretreated rats injected with /sup 203/Pb was fractionated via gel filtration and anion-exchange chromatography and disclosed that both Zn and /sup 203/Pb co-eluted in the MT fractions. Both purified ZnMT-I and ZnMT-II bound /sup 203/Pb in vitro as shown by gel filtration chromatography. Addition of purified liver ZnMT to purified bovine liver ALAD reaction mixtures increased enzyme activity by 2-fold and prevented ...

1987-05-01

19

Preparation of NiZn-ferrite nanofibers by electrospinning for DNA separation  

Energy Technology Data Exchange (ETDEWEB)

We present the synthesis, magnetic and UV spectrometry of NiZn-ferrite nanofiber. The single phase of spinel ferrite was obtained at 600 {sup o}C. The NiZn-ferrite fibers fabricated by an electrospinning process were formed as a polygonal grain growth with firing temperature in fiber matrix. It appeared that the saturation magnetization (M{sub S}) of NiZn-ferrite nanofiber was dependent on Ni/Zn molar ratio which is similar to that of the inverse spinel ferrites. The NiZn-ferrite fibers showed good DNA adsorption efficiency that can be modified and utilized for DNA separation with magnetic nanofiber as a novel material in clinical applications.

2009-05-15

20

Aluminum-Zinc (Al-Zn) Dust Analyses for Recycling Purposes  

Science.gov (United States)

... Accession Number : ADA547552. Title : Aluminum-Zinc (Al-Zn) Dust Analyses for Recycling Purposes. Descriptive Note : Technical rept. ...

2011-08-01

21

Conceptual design of the ATLAS EM muon chamber support structures  

CERN Document Server

The conceptual design of the support structures of the EM muon chambers is presented. On each side of the detector the EM chambers are arranged in four layers: one layer of MDTs and the three layers of TGCs. The chambers are mounted on four individual wheel structures per side. The four wheels are inclined by 1.23% and suspended from two longitudinal beams parallel to the beam axis. In order to allow for the opening of the ATLAS detector the wheels can be displaced longitudinally over a distance of 6 m. In addition individual wheels can be separated from each other by up to 1 m for maintenance purposes.

1998-01-01

22

Release of zinc from disposable coils during hemodialysis  

Energy Technology Data Exchange (ETDEWEB)

In a prior study, we demonstrated that certain disposable coils are contaminated with zinc and release substantial quantities of Zn during hemodialysis, producing high post-dialysis plasma Zn concentrations. The present investigation was designed to monitor plasma and dialysis fluid Zn and copper throughout dialysis and to estimate patient Zn and Cu uptake. Venous plasma, arterial plasma and coil chamber fluid were sampled periodically throughout dialysis; trace metal concentrations were determined by flame atomic absorption spectrophotometry. Release of considerable quantities of Zn from the coils into the dialysis fluid, with uptake into the patient's plasma, was found. Approximately one-half of the plasma Zn uptake occurred in the first 45 minutes. Coils from different lots released significantly different quantities of Zn. ...

1981-06-01

23

Amplified spontaneous emission from ZnO in n-ZnO/ZnO nanodots-SiO_2 composite/p-AlGaN heterojunction light-emitting diodes  

International Nuclear Information System (INIS)

This study demonstrates amplified spontaneous emission (ASE) of the ultraviolet (UV) electroluminescence (EL) from ZnO at #lambda##approx#380 nm in the n-ZnO/ZnO nanodots-SiO_2 composite/p- Al_0_._1_2Ga_0_._8_8N heterojunction light-emitting diode. A SiO_2 layer embedded with ZnO nanodots was prepared on the p-type Al_0_._1_2Ga_0_._8_8N using spin-on coating of SiO_2 nanoparticles followed by atomic layer deposition (ALD) of ZnO. An n-type Al-doped ZnO layer was deposited upon the ZnO nanodots-SiO_2 composite layer also by the ALD technique. High-resolution transmission electron microscopy (HRTEM) reveals that the ZnO nanodots embedded in the SiO_2 matrix have diameters of 3-8 nm and the wurtzite crystal structure, which allows the transport of carriers through the thick ZnO nanodots-SiO_2 composite layer. The high ...

2009-04-22

26

Know When to Hold`em: The Art of Restraint  

Science.gov (United States)

... Wiki Leaks (The Sunshine Press) Video, 39 min., 2010, electronic video, http://www.collateralmurder.com and http://wikileaks.org/ (accessed 11 ...

2010-05-03

28

Electron Microscope Database - GCMD - NASA  

Science.gov (United States)

Electron Microscope Database. Entry ID: em_database ... Ancillary Keywords. electron microscope. Data Set Progress. IN WORK. Originating Center ...

29

EMS and process of identification and evaluation of environmental aspects: a proposal methodology  

International Nuclear Information System (INIS)

The Environmental Management System (EMS) is an instrument to manage the interaction between the organization and the environment. The scope od EMS is to reduce the environmental impact and to achieve improvements in overall performances. In particular, the focus point of EMS implementation is the method for identifying and assessing significant environmental aspects. The results of the literature and regulation reviews (Perotto 2006) have shown that rigourous repeatable and transparent methodologies do not exist. This paper presents a proposal method for identifying and assessing significant environmental aspects, that has all three of these important characteristics. In particular, the proposal methodology for assessing aspects is based on some criteria that are combined in a specific algorithm. It is important to specify that to make a correct application of the method a preliminary rigorous approach to investigating the ...

2006-05-01

36

Influence of sewage sludge compost applications on uptake of element by cultivated crops in a brown forest soil. Measurement by neutron activation analysis  

International Nuclear Information System (INIS)

A field study was conducted to investigate the absorption of various elements into oats and carrots cultivated in brown forest soil after three years' applications of chemical fertilizer and two types of sewage sludge compost mixed with sawdust (SD compost) or rice husk (RH compost). The results obtained in this study are summarized as follows. 1) The application of SD compost led to a significant increase on the concentrations of Mn, Zn, Ag and Ba in oat root, of Zn and Br in oat shoot, of Cl and Zn in oat ears, of Mg, Sc, Mn, Zn, Br, Ba and La in carrot peel, of Mn, Fe, Co and Zn in carrot edible portion and of Na, Sc, Mn, Fe, Co and Sm in carrot shoot. 2) The application of RH compost increased the concentrations of Mn, Zn, and Ag in oat root, of K, Cr, Mn, Zn and Br in oat shoot, of Zn and Br in oat ears, of Mg, Mn ...

2006-03-01

37

Controllable growth and magnetic properties of nickel nanoclusters electrodeposited on the ZnO nanorod template  

International Nuclear Information System (INIS)

The ZnO nanorods were used as a template to fabricate nickel nanoclusters by electrodeposition. The ZnO nanorod arrays act as a nano-semiconductor electrode for depositing metallic and magnetic nickel nanoclusters. The growth sites of Ni nanoclusters could be controlled by adjusting the applied potential. Under -1.15 V the Ni nanoclusters could be grown on the tips of ZnO nanorods. On increasing the potential to be more negative the ZnO nanorods were covered by Ni nanoclusters. The magnetic properties of the electrodeposited Ni nanoclusters also evolved with the applied potentials.

2009-12-09

38

A hierarchical lattice structure and formation mechanism of ZnO nano-tetrapods  

International Nuclear Information System (INIS)

The existence of characteristic longitudinal optical and transverse optical phonons of cubic ZnO in ZnO nano-tetrapods is determined by Raman spectroscopy and first-principles calculations. Stacking sequence change at the boundary of the core and legs is also identified by high-resolution transmission electron microscopy. Based on this experimental and theoretical evidence, we demonstrate that the lattice structure of ZnO nano-tetrapods is hierarchical with a zinc blende core connecting to four wurtzite legs. Furthermore, we establish the atomic configuration and propose a formation mechanism induced by Laplace pressure in the initial growth stage of ZnO nano-tetrapods.

2009-08-12

39

Management of sampling and analysis activities in DOE`s Office of Environmental Management  

Energy Technology Data Exchange (ETDEWEB)

DOE`s Office of Environmental Management (EM) is responsible for managing waste and cleaning up contamination at DOE sites across the United States. A substantial fraction of the work performed for EM includes sampling and analysis activities. This paper outlines the Sample Management Programs, achievements to date, and future directions.

1995-12-31

40

Differences of the deformation parameter #beta# for 2"+_1 states of even-even spherical nuclei from electromagnetic excitation and proton scattering  

International Nuclear Information System (INIS)

Differences of the deformation parameters for the 2"+_1 states of even-even spherical nuclei extracted from electromagnetic excitation #beta#sup(em)_2 and from proton scattering #beta#sup(pp')_2 are discussed. It is found that the ratio #beta#sup(pp')_2/#beta#sup(em)_2 is equal to about unity and that there is a small isotope dependence for several incomplete shell nuclei. (orig.).

41

Thermally stimulated currents in ZnS sandwich structure deposited by spray pyrolysis  

Energy Technology Data Exchange (ETDEWEB)

Polycrystalline ZnS semiconducting films have been prepared in sandwich configuration by spray pyrolysis technique using ZnO-coated glass substrates and mixed aqueous solutions of ZnCl{sub 2} and thiourea. The sandwich structures have been produced successfully by means of ZnO-coated glass substrates. The produced ZnS films have been crystallized in a wurtzite structure and had a direct band gap energy of 3.62 eV. The electrical properties of the sample have been studied by an analysis based on the thermally stimulated current spectra in the temperature range of 40-300 K with various heating rates. A set of curves of I (T) for varying initial density of filled traps at a heating rate of {beta} {sub 2}=0.06 K s{sup -1} indicate that the observed peaks in the TSC curve of polycrystalline ZnS films have first-order features. In order to evaluate the trap parameters ...

2007-05-31

42

Solar syngas production from CO"2 and H"2O in a two-step thermochemical cycle via Zn/ZnO redox reactions: Thermodynamic cycle analysis  

British Library Electronic Table of Contents (United Kingdom)

Solar syngas production from CO"2 and H"2O is considered in a two-step thermochemical cycle via Zn/ZnO redox reactions, encompassing: 1) the ZnO thermolysis to Zn and O"2 using concentrated solar radiation as the source of process heat, and 2) Zn reacting with mixtures of H"2O and CO"2 yielding high-quality syngas (mainly H"2 and CO) and ZnO; the ZnO is recycled to the first, solar step, resulting in net reaction @bCO"2 + (1 - @b)H"2O -> @bCO + (1 - @b)H"2. Syngas is further processed to liquid hydrocarbon fuels via Fischer-Tropsch or other catalytic processes. Second-law thermodynamic analysis is applied to determine the cycle efficiencies attainable with and without heat recuperation for varying molar fractions of CO"2:H"2O and solar reactor temperatures in the range 1900-2300 K. Conside...

2011-01-01

43

Hydrogen evolution and corrosion performance of NiZn coatings  

International Nuclear Information System (INIS)

The hydrogen evolution reaction (HER) was studied on bare brass (B), nickel coated brass (B/Ni), nickel-zinc alloy coated brass (B/NiZn, leached Zn), nickel (under layer)/nickel-zinc alloy coated (top layer) brass electrodes (B/Ni/NiZn, leached Zn) in 1 M NaOH solution using electrolysis, cathodic polarization and electrochemical impedance spectroscopy (EIS) techniques. Long term tests were performed in order to evaluate the electrocatalytic activity and corrosion performance of the prepared electrodes with operation time. The results showed that leached electrodes, especially B/Ni/NiZn electrode, have a smaller overpotential than the others and a good electrocatalytic activity for the HER. Its electrocatalytic activity is also stable over electrolysis time. Contrary to the HER performance, B/NiZn cannot provide an adequate corrosion protection. However, when a ...

2007-02-01

44

Formation of ZnTe compounds by using the electrochemical ion exchange reaction in molten chloride  

Energy Technology Data Exchange (ETDEWEB)

The formation of ZnTe films was investigated on zinc substrates at 640 K by using the following ion exchange and chemical reaction processes,2Zn{sub (substrate)}+Te{sup 4+}{sub (inmoltensalts)}->2Zn{sup 2+}+Te{sub (onsubstrate)}Zn{sub (substrate)}+Te= {sub (onsubstrate)}-> ZnTe{sub (onsubstrate)}The Te{sup 4+} species was supplied to the substrate via the gas phase, vaporized from the eutectic LiCl-KCl molten salt containing TeCl{sub 4} (0.05-0.9 mol%). The phase of the films obtained depended on the reaction time and the TeCl{sub 4} content in the molten chloride. At low TeCl{sub 4} concentrations, ZnTe alloy was not formed over the entire surface even after 3.6 ks. On the other hand, at high TeCl{sub 4} concentrations, tellurium was detected in addition to the ZnTe compound during the first 0.3 ks of the reaction. By ...

2005-05-01

45

Development of novel brasses to resist dezincification  

Energy Technology Data Exchange (ETDEWEB)

The effect of alloying Sn, Pb, As, Sb and P on the dezincification of commercial brass 60Cu-39Zn-1Pb has been investigated in 1% CuCl{sub 2} solution by immersion studies and electrochemical measurements. Specimens with a smooth surface finish exhibited more resistance to dezincification. Appreciable inhibitive effect on dezincification was observed for the 55Cu-40Zn-3Pb-2Sn brass composition. The galvanic coupling of lead phase with the matrix accelerated corrosion. To improve the dezincification resistance of the Sn containing brass, As, Sb and P were added at two different levels (0.05% and 0.1%). Brass of composition 48.95Cu-45Zn-5Pb-1Sn-0.05As was more resistant indicating the synergistic effect of Sn and As. The effect of 0.05 and 0.1% of arsenic addition with various concentrations of zinc was also studied. The alloy of composition 57.90Cu-40Zn-2Pb-0.1As showed better corrosion resistance than ...

2007-03-15

46

ZnO microsheet modified TiO2 nanoparticle composite films for dye-sensitized solar cells  

British Library Electronic Table of Contents (United Kingdom)

Randomly oriented ZnO microsheets were successfully self-assembled on TiO2 nanoparticle (TN) film to act as the scattering layer via a cathodic electrodeposition process. The light scattering properties of ZnO microsheets were studied by UV-Vis spectrometer in the 400?800 nm wavelength range. It was found that ZnO microsheets exhibited excellent ability to scatter the incident light for ZnO microsheet-TiO2 nanoparticle (ZT) composite films. The results showed that dye-sensitized solar cells (DSSCs) fabricated with ZT composite films showed higher short-circuit density (J sc) and conversion efficiency than TN-based DSSCs, due to the light scattering properties of ZnO microsheets.

2010-01-01

47

Structural, optical, photocatalytic and antibacterial activity of zinc oxide and manganese doped zinc oxide nanoparticles  

British Library Electronic Table of Contents (United Kingdom)

Polycrystalline ZnO doped with Mn (5 and 10at%) was prepared by the co-precipitation method. The effect of Mn doping on the photocatalytic, antibacterial activities and the influence of doping concentration on structural, optical properties of nanoparticles were studied. Structural and optical properties of the particles elucidated that the Mn2+ ions have substituted the Zn2+ ions without changing the Wurtzite structure of ZnO. The optical spectra showed a blue shift in the absorbance spectrum with increasing dopant concentration. The photocatalytic activities of ZnO powders were evaluated by measuring the degradation of methylene blue (MB) in water under the UV region. It was found that undoped ZnO bleaches MB much faster than manganese doped ZnO upon its exposure to the U...

2010-01-01

48

Selective formation of ZnO nanodots on nanopatterned substrates by metalorganic chemical vapor deposition  

International Nuclear Information System (INIS)

Selective formation of ZnO nanodots was accomplished by metalorganic chemical vapor deposition on nanopatterned SiO_2/Si substrates. Self-organized ZnO nanodots were selectively formed in nanopatterned lines of Si created by etching of SiO_2 with focused ion beam (FIB), whereas any nanodots were hardly observed on the SiO_2 surface in the vicinity of the FIB-sputtered Si areas. The mechanism of the selective formation of ZnO nanodots on FIB-nanopatterned lines is mainly attributed to the effective migration of Zn adatoms diffusing on the SiO_2 surface into the Si lines followed by the nucleation at surface atomic steps and kinks created by Ga"+ ion sputtering. Cathodoluminescence measurements confirmed that the emission originated from the selectively grown ZnO nanodots.

2003-10-27

49

Adsorption of Pb^2^+ and Zn^2^+ from aqueous solutions by sulfured orange peel  

British Library Electronic Table of Contents (United Kingdom)

In this study, sulfured orange peel (MOP) was used as adsorbent to investigate its adsorption behaviors of Pb^2^+ and Zn^2^+ from aqueous solutions. The effects of solution pH, adsorption time and metal ion concentration on adsorption were studied in batch experiments. Both adsorption kinetics of Pb^2^+ and Zn^2^+ proceeded rapidly and could be well described by pesudo-second-order equation. The maximum Langmuir adsorption capacities for Pb^2^+ and Zn^2^+ removal by MOP were evaluated as 164 and 80mg/g, respectively. A binary mixture of Pb^2^+ and Zn^2^+ was studied by using a packed column, suggesting that effective mutual separation and pre-concentration of Pb^2^+ away from Zn^2^+ using MOP could be satisfactory achieved. The results indicate that MOP could be employed as an effective lo...

2011-01-01

50

Energy Management Action Network (EMAK). A scoping study investigating the establishment and support of an international and domestic action network of energy management in industry. Information paper  

Energy Technology Data Exchange (ETDEWEB)

The IEA has identified energy efficiency as essential to achieving a sustainable energy future. In order to improve energy efficiency in industry one of the priority areas for further action is the promotion of more and higher quality energy management (EM) activity. However, there are significant gaps in the current implementation of EM. One method of bridging these gaps would be the creation of an EM Action NetworK (EMAK) to bring practical support to energy managers, connect energy managers to energy policy makers, and interconnect these networks globally. The paper describes possible aims, activities, scope, structure, timelines and approaches related to EMAK and looks at specific tasks that would be important in the set-up and implementation.

2009-12-15

51

Assessment of cost savings of DOE's return-on-investment program  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy (DOE) Office of Pollution Prevention (EM-77) created is successful internally competed program to fund innovative projects based on projected returns. This is called the Return-on-Investment (ROI) program. EM-77 conducted a successful ROI pilot, developed and implemented sound management practices, and successfully transferred the program to several Operations Offices. Over the past 4 years sites have completed 262 ROI projects (costing $18.8 million) with claimed first-year savings of $88 million and claimed life cycle savings exceeding $300 million. EM-77 requested that Oak Ridge National Laboratory perform an independent evaluation of the site-led, DOE-HQ-funded pollution prevention (P2) ROI program to assist the Department in determining whether claimed savings are real.

1999-08-01

52

Zn, Cu, Cd and Hg binding to metallothioneins in harbour porpoises Phocoena phocoena from the southern North Sea  

UK PubMed Central (United Kingdom)

BackgroundHarbour porpoises Phocoena phocoena from the southern North Sea are known to display high levels of Zn and Hg in their tissues linked to their nutritional...Full Text Available

53

Photochemical synthesis of ZnO/Ag nanocomposites  

Energy Technology Data Exchange (ETDEWEB)

Composite ZnO/Ag nanoparticles have been formed via the photocatalytic reduction of silver nitrate over the ZnO nanocrystals, their optical, electrophysical and photochemical properties have been investigated. Mie theory has been applied to analyze the structure of the absorption spectra of ZnO/Ag nanocomposite. The irradiation effects upon the optical properties of ZnO/Ag nanostructure have been investigated. It has been found that the irradiation of ZnO/Ag nanoparticles results in electrons accumulation by both the semiconductor and the metallic components of the nanocomposite. It has been found that silver nitrate can be photochemically deposited onto the surface of ZnO nanoparticles under the illumination with the visible light in the presence of the sensitizer - methylene blue. Kinetics of the sensitized Ag(I) photoredution has been studied. It has been ...

2007-06-15

54

O2-dependent methionine auxotrophy in Cu,Zn superoxide dismutase-deficient mutants of Saccharomyces cerevisiae.  

UK PubMed Central (United Kingdom)

Mutant strains of the yeast Saccharomyces cerevisiae which lack functional Cu,Zn superoxide dismutase (SOD-1) do not grow aerobically unless supplemented with methionine. The molecular basis of this...Full Text Available

1990-04-01

55

H2/Ar and vacuum annealing effect of ZnO thin films deposited by RF magnetron sputtering system  

British Library Electronic Table of Contents (United Kingdom)

The properties of ZnO films were investigated as functions of annealing temperatures in H2/Ar and vacuum. The resistivities and mobilities of ZnO films decreased with increase of annealing temperatures in vacuum and H2/Ar ambients. However, the carrier densities of ZnO films increased with increase of annealing temperatures in vacuum and H2/Ar ambients. The resistivities of ZnO2 films annealed at 300degreeC were 2186cm and 798cm in H2/Ar and vacuum ambients, respectively. The resistivities of ZnO films annealed in vacuum and H2/Ar ambients at 600degreeC were similar with 0.040cm and 0.035cm, respectively. The hydrogen donor was more dominant than the oxygen vacancy or Zn interstitial donor in ZnO films annealed in ambient H2/Ar at low temperatures. The average optical transmission was >82%...

2010-01-01

56

Growth and characterisation of electrodeposited ZnO thin films  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical method has been used to deposit zinc oxide (ZnO) thin films from aqueous zinc nitrate solution at 80 deg. C onto fluorine doped tin oxide (FTO) coated glass substrates. ZnO thin films were grown between - 0.900 and - 1.025 V vs Ag/AgCl as established by voltammogram. Characterisation of ZnO films was carried out for both as-deposited and annealed films in order to study the effect of annealing. Structural analysis of the ZnO films was performed using X-ray diffraction, which showed polycrystalline films of hexagonal phase with (002) preferential orientation. Atomic force microscopy was used to study the surface morphology. Optical studies identified the bandgap to be {approx} 3.20 eV and refractive index to 2.35. The photoelectrochemical cell signal indicated that the films had n-type electrical conductivity and current-voltage measurements showed the ...

2008-04-30

57

Genome-Wide Transcriptional Response of Chemostat-Cultured Escherichia coli to Zinc  

UK PubMed Central (United Kingdom)

Zinc is an essential trace metal ion for growth, but an excess of Zn is toxic and microorganisms express diverse resistance mechanisms. To understand global bacterial responses to excess Zn, we conducted...Full Text Available

2005-02-01

58

Behavior at under-film corrosion tips of Zn-Fe alloy coated steel sheets. Zn-Fe gokin mekki koban no tomakushita fushoku ni okeru fushoku sentanbu no kyodo  

Energy Technology Data Exchange (ETDEWEB)

From a macroscopic point of view, corrosion of Zn alloy coated steel sheet occurs by the coating preceding corrosion mechanism; microscopically, however, the coated layer corrosion velocity in the tip of corrosion is different. In order to find the main factors of under-film corrosion of Zn and Zn-Fe alloy coatings in the salt water spray atmospheric exposure test, the correlation between point inflation-exfoliation width and chlorine penetration behavior, point adhesion, and the difference in chlorine penetration behavior due to alloy coating components were investigated. Consequently, the following results were obtained: 1. The better correlation was observed between chlorine penetration distance and point inflation-point exfoliation width. 2. The durability of coating against chlorine penetration improved by increase in point adhesion and Zn content in the coating layer. 3. Zn-Fe ...

1990-09-01

60

Development of conductive nanotemplates on ZnSe  

International Nuclear Information System (INIS)

We demonstrate the possibility to fabricate arrays of pores oriented perpendicular and parallel to the top surface of the ZnSe nanotemplate. The control of material conductivity allows one to produce porous ZnSe samples with the mean pore diameter and characteristic skeleton wall thickness from several hundreds of nanometers to about 15 nm. In addition, electrochemical treatment of ZnSe single crystals using photoresist masks allows one to prepare buried porous structures with pores directed parallel to the top template surface, which is especially important for photonic applications.

2011-07-07

61

Technology base research on zinc/air battery systems: Final report  

Energy Technology Data Exchange (ETDEWEB)

The capacity extension of additives was tested in a 200 cm/sup 2/bi-cell and a Zn powder moving-bed slurry. It was found that for the Type A additives in 12 M KOH, 25 g/l of silicate provided higher capacity than stannate, titanate and aluminate additives. The optimum concentration of sorbitol (a Type B additive that stabilizes polymeric chains involving ZnO) was found to be 15 g/l in 12 M KOH. A silicate and sorbitol combination added to Zn powder slurry in 12 M KOH provided a 20% increase in discharge capacity (195 Ah/l at 200 A/cm/sup 2/) compared to the maximum capacity obtained with silicate alone. A much lower capacity (74 Ah/l) was realized with silicate as Type C additive (precipitation of ZnO away from the Zn surface, for low KOH concentrations). The mechanisms of passivation and capacity extension were discussed and a model presented. The cell voltage and power densities ...

1987-09-01

62

Evaluation of adhesive plasters by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

A radiometric method was elaborated for surface density determinations of the adhesive layer of plasters by radionuclide X-ray fluorescence using the 17.47 keV bremsstrahlung of "1"4"7Pm/Mo. The bremsstrahlung line excites the 8.63 keV characteristic K#alpha# line of Zn contained in the adhesive layer of the plaster as a filling material in the form of ZnO. In homogeneous adhesive layers the Zn content is proportional to surface density. (author).

1976-01-01

63

Corrosion product role on the inhibition of Zn alloy electrodeposit corrosion  

Energy Technology Data Exchange (ETDEWEB)

Electrodeposited Zn alloys with Fe group metals are known to be more resistant than pure Zn. However, the role of the corrosion products on the corrosion inhibition is not considered up to date. The aim of the present work was to examine the composition of corrosion products, which form on the Zn and Zn alloy surfaces under atmospheric corrosion conditions up to 3 year of exposure, trying to correlate it with the differences in their corrosion resistance. Zn corrosion products have been characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Corrosion film composition was determined to depend on the sample exposure she, as well on the coating type. During the initial exposure stages oxide film was found to be the principal reaction product (XPS data), which in marine station consists from hydroxide phase exceptionally, while in urban one, contain up to ...

1998-12-31

64

Structure functions of nuclei in fluctonic model with rescaling  

International Nuclear Information System (INIS)

It is shown that the available data on x, Q"2, and A dependence of nuclear structure functions and for their ratios (EMS effect) can be described in terms of the flucton model with rescaling of parton distributions in nuclei. The x, Q"2 and A dependence of nuclear structure functions in the cumulative range (x >1) is predicted.

66

Flucton model with scaling breaking: EMC effect and lepton pair production on nuclei  

International Nuclear Information System (INIS)

The EMS effect is explained in the flucton model as a consequence of scale invariance violation. Nontrivial behaviour of the ratio between structural functions and production cross sections for lepton pairs for different nuclei at x > 1 is predicted.

68

Ecotoxicology of Explosives  

Energy Technology Data Exchange (ETDEWEB)

Managing sites contaminated with munitions constituents is an international challenge. Although the choice of approach and the use of Ecological Risk Assessment (ERA) tools may vary from country to country, the assurance of quality and the direction of ecotoxicological research are universally recognized as shared concerns. Drawing on a multidisciplinary team of contributors, 'Ecotoxicology of Explosives' provides comprehensive and critical reviews available to date on fate, transport, and effects of explosives. The book delineates the state of the science of the ecotoxicology of explosives, past, present, and recently developed. It reviews the accessible fate and ecotoxicological data for energetic materials (EMs) and the methods for their development. The chapters characterize the fate of explosives in the environment, then provide information on their ecological effects in key environmental media, including aquatic, sedimentary, and terrestrial ...

2009-04-01

69

EM-MWD technology; EM-MWD system jitsuyoka gijutsu  

Energy Technology Data Exchange (ETDEWEB)

A project on the title is a special study of TRC (Technology Research Center) Japan National Oil Corporation, which aims at developing a system collecting many data near well bottom while drilling. The project is a 3-year project from 1993 to 1995 succeeding to results of a project on real-time drilling control technology which was finished in fiscal 1992. This paper is a record in fiscal 1993. In 1993, the first year, TRC starts a joint study with relational enterprises aiming at utilizing an EM-MWD (electromagnetic-measurement while drilling) system practically. Based on the past fruit of the study, the EM-MWD system was applied to an highly inclined well or a horizontal well. A total system was constructed, which improved electromagnetic radiation transmission efficiency, and reliability, and workability. An electromagnetic radiation receiver system for an offshore drilling rig was developed. A well bottom tools of 6-3/4 inches outer ...

1994-10-31

72

CRED Simrad em300 multibeam backscatter data from the submarine slope environment at Rose Island, American Samoa, South ...  

Science.gov (United States)

Multibeam backscatter imagery extracted from gridded bathymetry of Rose Island, American Samoa, South Pacific. These data provide coverage between 20 ... ...

74

State of work for services provided by the Waste Sampling and Characterization Facility for effluent monitoring  

International Nuclear Information System (INIS)

This document defines the services the Waste Sampling and Characterization Facility (WSCF) shall provide Effluent Monitoring (EM) throughout the calendar year for analysis. The internal memo contained in Appendix A identifies the samples Em plans to submit for analysis in CY-1995. Analysis of effluent (liquid and air discharges) and environmental (air, liquid, animal, and vegetative) samples is required using standard laboratory procedures, in accordance with regulatory and control requirements. This report describes regulatory reporting requirements and WSCF services and data quality objectives.

75

Hanford tanks initiative plan  

Energy Technology Data Exchange (ETDEWEB)

Abstract: The Hanford Tanks Initiative (HTI) is a five-year project resulting from the technical and financial partnership of the U.S. Department of Energy`s Office of Waste Management (EM-30) and Office of Science and Technology Development (EM-50). The HTI project accelerates activities to gain key technical, cost performance, and regulatory information on two high-level waste tanks. The HTI will provide a basis for design and regulatory decisions affecting the remainder of the Tank Waste Remediation System`s tank waste retrieval Program.

1997-07-01

76

Development of the SRS environmental counting laboratory gamma spectroscopy system  

International Nuclear Information System (INIS)

The Savannah River Site (SRS), one of several U.S. Department of Energy (DOE) facilities, produces nuclear materials for national defense and for other government and civilian uses. SRS ceased production of defense materials in 1988, and the site's main activities now involve waste management and environmental restoration. These programs have generated extensive effluent monitoring and environmental surveillance programs for the Environmental Monitoring Section (EMS), which performs #approx#105,000 radiological analyses on 30,000 samples a year. Gamma spectroscopy is performed on an estimated 10,000 samples annually. This report describes a program to develop and improve the EMS system.

1996-06-16

77

Ten-year cleanup of U.S. Department of Energy weapon sites: The changing roles for technology development in an era of privatization  

Energy Technology Data Exchange (ETDEWEB)

In its beginning, the U.S. Department of Energy (DOE) Office of Environmental Management (EM) viewed private industry as lacking adequate technology know-how to meet demands of hazardous and radioactive waste problems at the DOE`s laboratories and nuclear weapons production facilities. In November 1989, EM`s Office of Technology Development (recently renamed the Office of Science and Technology) embarked on a bold program of developing and demonstrating {open_quotes}innovative{close_quotes} waste cleanup technologies that would be safer, faster, more effective, and less expensive than the {open_quotes}baseline{close_quotes} commercial methods. This program has engaged DOE sites, national laboratories, and universities to produce preferred solutions to the problems of handling and treating DOE wastes. More recently, much of this work has shifted to joint efforts with private industry partners to accelerate the use of newly developed technologies ...

1996-12-31

78

Geophysical remote sensing of water reservoirs suitable for desalinization.  

Energy Technology Data Exchange (ETDEWEB)

In many parts of the United States, as well as other regions of the world, competing demands for fresh water or water suitable for desalination are outstripping sustainable supplies. In these areas, new water supplies are necessary to sustain economic development and agricultural uses, as well as support expanding populations, particularly in the Southwestern United States. Increasing the supply of water will more than likely come through desalinization of water reservoirs that are not suitable for present use. Surface-deployed seismic and electromagnetic (EM) methods have the potential for addressing these critical issues within large volumes of an aquifer at a lower cost than drilling and sampling. However, for detailed analysis of the water quality, some sampling utilizing boreholes would be required with geophysical methods being employed to extrapolate these sampled results to non-sampled regions of the aquifer. The research in this report addresses using ...

2009-12-01

79

ZnO nanoparticles enhanced antibacterial activity of ciprofloxacin against Staphylococcus aureus and Escherichia coli  

British Library Electronic Table of Contents (United Kingdom)

Nanoparticle metal oxides offer a wide variety of potential applications in medicine due to the unprecedented advances in nanobiotechnology research. In this work, the effect of zinc oxide (ZnO) nanoparticles prepared by mechano-chemical method on the antibacterial activity of different antibiotics was evaluated using disk diffusion method against Staphylococcus aureus and Escherichia coli. The average size of ZnO nanoparticles was between 20 nm and 45 nm. Although ZnO nanoparticles (500 mg/disk) decreased the antibacterial activity of amoxicillin, penicillin G, and nitrofurantoin in S. aureus, the antibacterial activity of ciprofloxacin increased in the presence of ZnO nanoparticles in both test strains. A total of 27% and 22% increase in inhibition zone areas was observed for ciprofloxac...

2010-01-01

80

TEM analyses of heterogeneous nucleation of internally oxidised multi-component Ag-Zn-based alloys  

Energy Technology Data Exchange (ETDEWEB)

The aim of our research was to identify structures and chemical compositions of phases formed during internal oxidation of multi-component Ag-Zn-Mg-based alloys. Since the ability of inoculation mostly depends on large free energy of formation of oxides of microalloying elements and their crystallographic similarity, Mg in quantities of 0.001-0.5 mass% was selected as a micro-alloying element. These correspond to the quantities of 0.005-2.5 vol.% of MgO in the selected Ag-Zn-based alloys. Ag-based metal matrix, heterogeneous nuclei of MgO and oxide (ZnO) of the main alloying element were analysed by transmission electron microscopy (TEM). Structural inter-connections among them were also investigated and analysed. In situ phenomenon of heterogeneous nucleation of MgO and ZnO was proved. (orig.)

2001-11-01

81

Synthesis and characterization of undoped and TM (Co, Mn) doped ZnO nanoparticles  

British Library Electronic Table of Contents (United Kingdom)

Antibacterial activity of Transition metals (Mn, Co) doped ZnO nanopowders prepared by a DC thermal plasma method against Escherichia coli and Staphylococcus aureus are investigated. The phase and morphology studies have been carried out by X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) respectively. All the samples of the present investigation are found to have hexagonal wurtzite structure and crystallite sizes are found to vary from 25nm to 30nm. Our bacteriological study showed the enhanced antibacterial activity of transition metals doped ZnO nanoparticles than undoped ZnO indicating the great potential of ZnO nanoparticles in relevant clinical and biomedical applications.

2011-01-01

82

Properties of transition metal-doped zinc chalcogenide crystals for tunable IR laser radiation  

Energy Technology Data Exchange (ETDEWEB)

The spectroscopic properties of Cr{sup 2+}, Co{sup 2+}, and Ni{sup 2+}-doped single crystals of ZnS, ZnSe, and ZnTe have been investigated to understand their potential application as mid-IR tunable solid-state laser media. The spectroscopy indicated divalent Cr was the most favorable candidate for efficient room temperature lasing, and accordingly, a laser-pumped laser demonstration of Cr:ZnS and Cr:ZnSe has been performed. The lasers` output were peaked at {approximately} 2.35 {mu}m and the highest measured slope efficiencies were {approximately} 20% in both cases.

1995-03-17

83

Pressure-dependent photoluminescence study of ZnO nanowires  

Energy Technology Data Exchange (ETDEWEB)

The pressure dependence of the photoluminescence (PL) transition associated with the fundamental band gap of ZnO nanowires has been studied at pressures up to 15 GPa. ZnO nanowires are found to have a higher structural phase transition pressure around 12 GPa as compared to 9.0 GPa for bulk ZnO. The pressure-induced energy shift of the near band-edge luminescence emission yields a linear pressure coefficient of 29.6 meV/GPa with a small sublinear term of -0.43 meV/GPa{sup 2}. An effective hydrostatic deformation potential -3.97 eV for the direct band gap of the ZnO nanowires is derived from the result.

2004-09-13

84

Genesis of the Jurassic Carbonate-Hosted Pb-Zn Deposits of Jebel Ressas (North-Eastern Tunisia): Evidence from Mineralogy, Petrography and Trace Metal Contents and Isotope (O, C, S, Pb) Geochemistry  

British Library Electronic Table of Contents (United Kingdom)

Abstract The Jebel Ressas Pb-Zn deposits in North-Eastern Tunisia occur mainly as open-space fillings (lodes, tectonic breccia cements) in bioclastic limestones of the Upper Jurassic Ressas Formation and along the contact of this formation with Triassic rocks. The galena-sphalerite association and their alteration products (cerussite, hemimorphite, hydrozincite) are set within a calcite gangue. The Triassic rocks exhibit enrichments in trace metals, namely Pb, Co and Cd enrichment in clays and Pb, Zn, Cd, Co and Cr enrichment in carbonates, suggesting that the Triassic rocks have interacted with the ore-bearing fluids associated with the Jebel Ressas Pb-Zn deposits. The 18O content of calcite associated with the Pb-Zn mineralization suggests that it is likely to have precipitated from a fl...

2011-01-01

85

Converting hcp Mg-Al-Zn alloy into bcc Mg-Li-Al-Zn alloy by electrolytic deposition and diffusion of reduced lithium atoms in a molten salt electrolyte LiCl-KCl  

Energy Technology Data Exchange (ETDEWEB)

A body-centered cubic (bcc) Mg-12Li-9Al-1Zn (wt.%) alloy was fabricated in air by electrolysis from LiCl-KCl molten salt at 500 deg. C. Electrolytic deposition of Li atoms on cathode (Mg-Al-Zn alloy) and diffusion of the Li atoms formed the bcc Mg-Li-Al-Zn alloy with 12 wt.% Li and only 0.264 wt.% K. Low K concentration in the bcc Mg alloy strip after the electrolysis process resulted from 47% atomic size misfit between K and Mg atoms and low solubility of K in Mg matrix.

2007-04-15

86

Converting hcp Mg-Al-Zn alloy into bcc Mg-Li-Al-Zn alloy by electrolytic deposition and diffusion of reduced lithium atoms in a molten salt electrolyte LiCl-KCl  

British Library Electronic Table of Contents (United Kingdom)

A body-centered cubic (bcc) Mg-12Li-9Al-1Zn (wt.%) alloy was fabricated in air by electrolysis from LiCl-KCl molten salt at 500degreeC. Electrolytic deposition of Li atoms on cathode (Mg-Al-Zn alloy) and diffusion of the Li atoms formed the bcc Mg-Li-Al-Zn alloy with 12wt.% Li and only 0.264wt.% K. Low K concentration in the bcc Mg alloy strip after the electrolysis process resulted from 47% atomic size misfit between K and Mg atoms and low solubility of K in Mg matrix.

2007-01-01

87

Surface oxidation processes in compound semiconductors studied by profile imaging  

International Nuclear Information System (INIS)

The profile imaging technique is used to study the oxidation of ZnTe and InP surfaces induced by in situ reaction due to the electron beam of the microscope and by ex situ heating in air. For both materials, in situ reaction with the electron beam resulted in desorption of the anion species and the formation of the metal oxide. The observation of In metal particles, and the fact that the rate of formation of In_2O_3 was substantially reduced by an improvement of the vacuum near the specimen region, suggested that the presence of oxygen is not involved in the desorption process. The ex situ heating of ZnTe up to 260 degrees C in air resulted in crystals of ZnO and Te metal, generally in a layered surface region with the sequence of ZnTe/Te/ZnO. The large Te crystals usually had an epitaxial relationship with the bulk ZnTe but the small ZnO crystals had random ...

88

Preparation of ZnO varistors by solution nano-coating technique  

Energy Technology Data Exchange (ETDEWEB)

This paper introduces a new method to produce nano-composite powder for the preparation of high performance ZnO varistors. ZnO particles were coated with Bi{sub 2}O{sub 3}, Sb{sub 2}O{sub 3}, Co{sub 2}O{sub 3}, Cr{sub 2}O{sub 3} and other additives via liquid nano-coating technique. Then the prepared powder was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravity and differential scanning calorimetry (TG-DSC) and particle size distribution. The results showed that the ZnO composite powder is homogeneously coated and ultrafine. The densification, phase composition and microstructure of ZnO varistors was studied by linear shrinkage, X-ray diffraction (XRD) and SEM, respectively. The preliminary electrical parameters of ZnO varistors showed that the breakdown voltage V {sub b} (1 mA/cm{sup 2}) and nonlinear coefficient {alpha} is ...

2006-06-15

89

Low-temperature synthesis and room temperature ultraviolet lasing of nanocrystalline ZnO films  

Energy Technology Data Exchange (ETDEWEB)

Nanocrystalline ZnO films were fabricated via a simple method involving the oxidation of Zn films at a remarkably low temperature of 380 C. X-ray diffraction study confirmed that the Zn films were completely oxidized even at the low temperature of 380 C and the ZnO films fabricated were of polycrystalline wurtzite structure. Room temperature optical pumping using a frequency-quintupled Q-switched Nd:YAG laser ({lambda}=213 nm) exhibited that sharp peaks at around 3.12 eV emerged above excitation powers of {proportional_to}7 MW/cm{sup 2}, demonstrating lasing in the ZnO films. These results represent that the process is a simple, promising approach for fabricating ZnO of sufficient optical performance for use as ultraviolet (UV) light emitters and an alternative UV laser source; both are key components in short-wavelength photonic devices. (orig.)

2005-02-01

90

Compost amendment of Cu-Zn minespoil reduces toxic bioavailable heavy metal concentrations and promotes establishment and biomass production of Bromus carinatus (Hook and Arn.)  

International Nuclear Information System (INIS)

A series of lab and greenhouse studies were undertaken to understand how Cu and Zn toxicity influences Bromus carinatus (Hook and Arn.) growth, to what degree an organic amendment (yard waste compost) may reduce Cu and Zn bioavailability in Cu-Zn minespoil and promote plant growth in combination with fertilizer, and how the vertical distribution of compost in the minespoil influences rooting depth. Root Cu and Zn toxicity thresholds were determined to be 1 mg L"-"1 and 10 mg L"-"1 in solution, respectively. The compost amendment had exceptionally high Cu and Zn binding capacities (0.17 and 0.08 g metal g C"-"1, for Cu and Zn, respectively) that were attributed to high compost humic and fulvic acid concentrations. Maximum plant biomass was achieved when minespoil was amended with compost and fertilizer in combination. Fertilizer alone had no effect on plant ...

2007-07-01

91

Zn-Al alloy as a new anode-metal of a zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

Low operating power and short cycle life are 2 of the main draw-backs of zinc-air batteries, despite the fact that various attempts have been made to develop improved zinc (Zn) anodes. This study investigated the performance of a Zn anode with a substantial addition of aluminium (Al). Rolled sheets of Zn-Al alloys of varying amounts of Zn and Al were used to prepare the anodes. Results of the study showed that the cells had higher open circuit voltages (OCV) values as well as a higher specific anode capacity. It was observed that specific anode capacity increased with higher current loading. The Zn{sub 59}Al{sub 41} and Zn{sub 67}Al{sub 33} sheets showed the highest performance with high OCV values of between 1540 and 1560 mV, as well as the largest specific anode capacity of 750-800 mAh per g at a discharge current of 200 mA. The 2-phase structure of the ...

2006-01-15

92

Valence-band offsets at the Al{sub x}Ga{sub 0.5{minus}x}In{sub 0.5}P-ZnSe(001) lattice-matched interface  

Energy Technology Data Exchange (ETDEWEB)

The difficulty in making good Ohmic contact at the interfaces with p-doped ZnSe is an important problem hindering the realization of blue-light-emitting diode lasers based on the II-VI semiconductor technology. So far no metal or semiconductor material has been found to have a low enough barrier at the (001) interface with ZnSe. A possible solution to this problem is the insertion of a so-called {ital barrier-reduction layer} at the interface with ZnSe. We have investigated the interface formation energies and valence-band offsets at the (001) interface between Al{sub x}Ga{sub 0.5{minus}x}In{sub 0.5}P and ZnSe. The results of our calculations show the existence of a strong interdependence between the valence-band offset and the interface geometric structure. The interface is found to have structural and electronic similarities to the GaAs-ZnSe(001) system. The very low values ...

1997-01-01

93

Electronic topological transition in zinc metal? A "6"7Zn-Moessbauer investigation  

International Nuclear Information System (INIS)

The question concerning the existence of an electronic topological transition (ETT) in Zn metal under quasi-hydrostatic pressure at #approx#6.6 GPa caused a considerable controversy in the literature. We briefly review low-temperature "6"7Zn-Moessbauer data and scalar-relativistic augmented plane wave calculations and give a consistent interpretation in terms of an ETT. To highlight some important aspects of the controversy two theoretical and two experimental publications will be discussed in more detail. At present the existence of an ETT in Zn metal is disputed both from an experimental and from a theoretical point of view. The suggestion of a transition to a commensurate spin-density wave at #approx#6.6 GPa instead of an ETT may reconcile the seemingly contradictory results of "6"7Zn-Moessbauer experiments at 4.2 K and of room temperature inelastic neutron scattering measurements. However, it does ...

2000-11-01

94

Zinc determination in medicinal powders by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

X-ray fluorescence analysis was used to determine the zinc content of the ''Perilacin'' powder and the ZnO content of the ''Epiderman-pix'' powder. The characteristic Ksub(#alpha#) line of zinc was excited using a "1"4"7Pm/Mo source (10"7 s"-"1) and the molybdenum Ksub(#alpha#) line (17.47 keV). 4 to 5% Zn and 45 to 49% ZnO were determined with a NaI(Tl) scintillation detector. The radiation intensity was found to decrease with particle size. (M.K.).

1977-01-01

95

Temperature Dependences of Leakage Currents of ZnO Varistors Doped with Rare-Earth Oxides  

British Library Electronic Table of Contents (United Kingdom)

Rare-earth oxides are doped into ZnO varistors as grain growth inhibitors for increasing the varistors' voltage gradients. However, their leakage currents become large and their nonlinear coefficients decrease at the same time. The reasonable explanation for such a phenomenon has not yet been available. In this paper, the temperature dependences of varistor samples' leakage currents are investigated, which reveal that the increased leakage currents of ZnO varistors with Y2O3 doping are mainly due to the bypass paths through the intergranular materials at grain corners.

2010-01-01

96

Neutron scattering study on the normal-incommensurate phase transition in K2ZnCl4  

Energy Technology Data Exchange (ETDEWEB)

The normal-incommensurate phase transition in K2ZnCl4 was studied by neutron scattering measurements. A well-defined soft phonon behavior was not observed above the normal-incommensurate transition temperature of Tsub(i)=288C. Diffuse scattering develops around(h,0,1 +- 0.3) as temperature approaches Tsub(i) from above, and the peak intensity obeys a Curie-Weiss law above Tsub(i). The results indicate that the normal-incommensurate phase transition in K2ZnCl4 can be interpreted as an order-disorder process.

1984-12-01

97

Modeling of an electrically rechargeable alkaline zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

A numerical model has been developed to simulate the charging and discharge behaviour of an electrically rechargeable alkaline zinc-air battery. Further a galvanostatic experiment including three charge/discharge cycles has been performed. The cell voltages, the Zn electrode potentials versus a Zn reference, and the O{sub 2} electrode potentials versus a Zn reference calculated with the model are in fairly good agreement with the corresponding experimental data. The model is expected to be useful for zinc-air battery design and for analysis of experimental data. (author)

2003-03-01

98

Local Heine-Abarenkov model potential for III-V and II-VI covalent compounds  

Energy Technology Data Exchange (ETDEWEB)

A local Heine-Abarenkov model potential is proposed for zinc blende-type crystals. The potential parameters are determined by satisfying the zero pressure condition and the first zero of the empirical pseudopotential interpolated from band calculations. Two sets of parameters are presented for thirteen tetrahedral compounds such as AlP, AlAs, AlSb, GaP, GaAs, GaSb, InP, InAs, InSb, ZnS, ZnSe, ZnTe, and CdTe.

1983-10-01

99

Transient heat transfer in a directly-irradiated solar chemical reactor for the thermal dissociation of ZnO  

International Nuclear Information System (INIS)

A numerical and experimental investigation is carried out in a solar thermochemical reactor for the thermal dissociation of ZnO at 2000 K using concentrated solar energy. The reactor consists of a cavity-receiver lined with ZnO particles and directly exposed to high-flux irradiation. A transient heat transfer model is formulated to link the rate of radiation, convection, and conduction heat transfer to the reaction kinetics. The radiosity and Monte Carlo methods are applied to obtain the distribution of net radiative fluxes at the internal surfaces of the reactor cavity and at the surface of the ZnO bed. Validation is accomplished in terms of the calculated and measured transient temperature profiles and chemical reaction rates.

2008-04-01

101

Technology base research on the slurry-zinc/air battery system: Final report  

Energy Technology Data Exchange (ETDEWEB)

The slurry-Zn/air battery system has received renewed R and D interest because it does not have the shape-change problems of batteries with Zn-plate electrodes and can sustain higher current densities and specific peak power than other metal-air battery systems. Additional advantages of the slurry-Zn/air battery include safety, low environmental impact, potential low cost, and separation of energy density from power density functions for design purposes. In this work we present results obtained at the individual cell level as a basis to estimate the performance of a secondary slurry-Zn/air battery system. The expected specific energy of such systems has been increased as a result of the use of capacity-extension additives, which has been one of the major thrusts of this work. 8 refs., 20 figs., 5 tabs.

1988-08-01

104

Investigation by XRF and XRD of Zn and Fe in Fe{sub x} Zn{sub 1-x} thin films  

Energy Technology Data Exchange (ETDEWEB)

Fe{sub x}Zn{sub 1-x} alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K{beta}/K{alpha} x-ray intensity ratios of Zn and Fe in Fe{sub x}Zn{sub 1-x} thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi {sup 241}Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in Fe{sub x}Zn{sub ...

2008-12-15

105

Investigation by XRF and XRD of Zn and Fe in Fex Zn1-x thin films  

International Nuclear Information System (INIS)

FexZn1-x alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K?/K? x-ray intensity ratios of Zn and Fe in FexZn1-x thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi 241Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in FexZn1-x thin films for different values of x. The reason ...

2008-12-01

106

Half-Heusler phase related structural perturbations near stoichiometric composition FeZnSb  

International Nuclear Information System (INIS)

Half-Heusler phases XYZ (Pearson symbol cF12) are chemically versatile and rich in physical properties. The half-Heusler phase in the Fe-Zn-Sb ternary system was reported in the year 2000. In this work, two new ternary phases are identified in the vicinity of the equiatomic composition FeZnSb in the same system: Fe1-xZnSb (tetragonal, space group P4/nmm, Pearson symbol tP6-?, Z=2: a=4.1113(6) A, c=6.0127(12) A for x=0.08 (1), and a=4.1274(6) A, c=6.0068(12) A for x=0.12 (2)); and Fe7.87Zn6.72Sb8 (Fe0.98Zn0.84Sb) (3) (cubic, space group Fm-3m, Pearson symbol cF96-?, Z=4, a=11.690(13) A). 1 and 2 crystallize in the PbFCl-type structure, and 3 adopts a unique 2x2x2 supercell of a normal half-Heusler structure. The structures of both the tetragonal and cubic phases can be described as assemblies of half-Heusler structure related subunits. Electrical resistivity measurement on the pure ...

2011-05-01

107

Effect of zinc and its form of supply on production and quality of coffee beans  

British Library Electronic Table of Contents (United Kingdom)

Abstract BACKGROUND: In Brazil, the usual forms of zinc (Zn) supply to coffee plants have limitations that compromise the element availability to the plant. This study proposes to test an alternative approach to supplying the nutrient to Coffea arabica L. using trunk implanted zinc tablets. Additionally, the effect of Zn on the production and quality of coffee beans was also evaluated. RESULTS: The highest total coffee bean production was recorded in plants implanted with Zn tablets (TA), while the lowest was recorded in the control treatment, without zinc supply (WZn), reaching a bianual production of 188.2 and 130.1 60-kg bags of processed beans per hectare, respectively. In the treatments where Zn were applied as tablet implantation or as foliage spraying (SZn); the bean size was larger...

2011-01-01

108

Biochemical alterations induced by Zn and Cd individually or in combination in the serum of Oreochromis niloticus  

British Library Electronic Table of Contents (United Kingdom)

Measurement of serum biochemical parameters in response to metal exposures can be especially useful to help identify target organs of toxicity as well as the general health status of animals. Oreochromis niloticus were exposed to 5.0?mg/L?Zn, 1.0?mg/L?Cd, and 5.0?mg/L?Zn?+?1.0?mg/L?Cd mixture for 7 and 28?days, and alterations in serum enzyme activities and ion levels were measured. Significant changes in all the biochemical parameters were found to be time dependent. Following metal exposure, alkaline phosphatase activity was elevated at both exposure periods. No changes in activities of lactate dehydrogenase and lipase were observed in response to single or combined Zn and Cd exposure at 7?days while they increased at 28?days. Fish exposed to metals showed a decrease in cholinesterase ac...

2010-01-01

110

X-ray, Optical, and Radio Observations of SN 1999em and SN 1998S  

CERN Document Server

Observations of the Type II-P (plateau) Supernova (SN) 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first and only Type II-P detected at both X-ray and radio wavelengths. It is the least radio luminous and one of the least X-ray luminous SN ever detected (except for the unusual and very close SN 1987A). The Chandra X-ray data indicate non-radiative interaction of SN ejecta with a power-law density profile (rho \\propto r^{-n} with n ~ 7) with a pre-SN wind with a low mass loss rate of ~2 \\times 10^{-6} Msun/yr for a wind velocity of 10 km/sec, in close agreement with radio mass-loss rate estimates. The Chandra data show an unexpected, temporary rise in the 0.4--2.0 keV X-ray flux at ~100 days after explosion. SN 1998S appears reasonably ...

2001-01-01

111

The Quantum Vacuum of Complex Media. A Unified Approach to the Dielectric Constant, the Spontaneous Emission and the Zero-Temperature Electromagnetic Pressure  

CERN Document Server

We study from a critical perspective several quantum-electrodynamic phenomena commonly related to vacuum electromagnetic (EM) fluctuations in complex media. We compute the resonance-shift, the spontaneous emission rate, the local density of states and the van-der-Waals-Casimir pressure in a dielectric medium using a microscopic diagrammatic approach. We find, in agreement with some recent works, that these effects cannot be attributed to variations on the energy of the EM vacuum but to variations of the dielectric self-energy. This energy is the result of the interaction of the bare polarizability of the dielectric constituents with the EM fluctuations of an actually polarized vacuum. We have found an exact expression for the spectrum of these fluctuations in a statistically homogeneous dielectric. Those fluctuations turn out to be different to the ones of normal radiative modes. It is the latter that carry the ...

2009-01-01

112

In Situ Remediation Integrated Program: FY 1994 program summary  

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy (DOE) established the Office of Technology Development (EM-50) as an element of the Office of Environmental Management (EM) in November 1989. In an effort to focus resources and address priority needs, EM-50 introduced the concept of integrated programs (IPs) and integrated demonstrations (IDs). The In Situ Remediation Integrated Program (ISR IP) focuses research and development on the in-place treatment of contaminated environmental media, such as soil and groundwater, and the containment of contaminants to prevent the contaminants from spreading through the environment. Using in situ remediation technologies to clean up DOE sites minimizes adverse health effects on workers and the public by reducing contact exposure. The technologies also reduce cleanup costs by orders of magnitude. This report summarizes project work conducted in FY 1994 under the ISR IP in three major areas: treatment ...

1995-04-01

113

From waste minimization to ISO 14000: Taiwan`s experience and prospects  

Energy Technology Data Exchange (ETDEWEB)

Taiwan has completed a very successful five-year industrial waste minimization (IWM) demonstration and promotion project sponsored by the government. From 1990 to 1995, the project successfully disseminated the IWM concept of pollution prevention (P2) to industries. It effectively reduced industrial waste while significantly benefitting the economy by assisting industries in implementing in-plant IWM programs. In July 1995, the second stage of the five-year IWM and ISO 14000 promotion project was initiated for further promoting the IWM, P2, and cleaner production and, in particular, coping with the upcoming international environmental management standards (ISO 14000). To assist industries in establishing an environmental management system (EMS) and accumulating related experience, an EMS pilot demonstration project of five model industries and an ISO 14001 EMS demonstration and promotion project for 22 factories in 13 ...

1996-12-31

114

UNITED STATES DEPARTMENT OF ENERGY WASTE PROCESSING ANNUAL TECHNOLOGY DEVELOPMENT REPORT 2007  

Energy Technology Data Exchange (ETDEWEB)

The Office of Environmental Management's (EM) Roadmap, U.S. Department of Energy--Office of Environmental Management Engineering & Technology Roadmap (Roadmap), defines the Department's intent to reduce the technical risk and uncertainty in its cleanup programs. The unique nature of many of the remaining facilities will require a strong and responsive engineering and technology program to improve worker and public safety, and reduce costs and environmental impacts while completing the cleanup program. The technical risks and uncertainties associated with cleanup program were identified through: (1) project risk assessments, (2) programmatic external technical reviews and technology readiness assessments, and (3) direct site input. In order to address these needs, the technical risks and uncertainties were compiled and divided into the program areas of: Waste Processing, Groundwater and Soil Remediation, and Deactivation and Decommissioning ...

2008-08-12

115

Use of surface affinity enrichment and cryo-embedding to prepare in vitro reconstituted mitotic chromosomes for EM tomography  

Energy Technology Data Exchange (ETDEWEB)

We present a novel preparation method for studies of in vitro reconstituted mitotic chromosomes from Xenopus laevis egg extracts. This method involves a gentle adsorption of chromosomes from the extracts using surface affinity enrichment, followed by plunge freezing, freeze-substitution and cryo-embedding before examination by EM tomography. For comparison, chromosomes were also prepared by a conventional method, which included immobilization of chromosomes in agarose and a room-temperature dehydration (embedding) protocol. Three-dimensional reconstructions showed that samples prepared with the new method have a greater interconnectivity of sub-structural features and a higher compaction ratio together with an apparently less perturbed chromatin structure than those prepared using the conventional approach. The implications of the new method for the preparation of other difficult samples and additional application possibilities are discussed.

2005-07-15

116

The Bedwyr system for model checking over syntactic expressions  

CERN Document Server

Bedwyr is a generalization of logic programming that allows model checking directly on syntactic expressions possibly containing bindings. This system, written in OCaml, is a direct implementation of two recent advances in the theory of proof search. The first is centered on the fact that both finite success and finite failure can be captured in the sequent calculus by incorporating inference rules for {\\em definitions} that allow {\\em fixed points} to be explored. As a result, proof search in such a sequent calculus can capture simple model checking problems as well as may and must behavior in operational semantics. The second is that higher-order abstract syntax is directly supported using term-level $\\lambda$-binders and the quantifier known as $\

2007-01-01

117

Surface equation of state for pulmonary surfactant monolayers at Air-Water interface: Protein-lipid binary mixture monolayers  

British Library Electronic Table of Contents (United Kingdom)

Abstract The available surface equation of state for pure pulmonary surfactant monolayers is generalised to binary mixture monolayers by introducing a group of parameters, i(i-=-1-4) in the form of $x_{r}^{\\beta _{i} } $ to express the influence of the components in new mixing rules and a new factor, I $\\left[ { = \\left( {\\prod\\limits_{i = 1}^{4} {\\beta _{i} } } \\right)^{{\\raise0.5ex\\hbox{$\\scriptstyle 1$}\\kern-0.1em/\\kern-0.15em\\lower0.25ex\\hbox{$\\scriptstyle {4}$}}} } \\right]$, is defined to represent the interaction intensity between two different components. The ---A isotherms getting by the surface equations of state agree with the experimental data for protein-lipid binary monolayers, and the average deviation is about 11.41%. The result shows the order of the interaction intensity b...

2010-01-01

118

On external network model development  

Energy Technology Data Exchange (ETDEWEB)

Although state estimation is a mature technique which is widely available in the EMS industry, experience with practical implementation and use of state estimation and network security analysis functions at electric power utilities over the last two decades indicates recurring difficulties and problems attributable to inadequate external network modeling detail and data. This paper addresses the development of a set of guidelines for external network modeling and data exchange, based on the results of a recent project sponsored by EPRI. A general methodology is developed based on the results of a survey of a representative set of utilities and EMS suppliers, supplemented by subsequent analysis and simulation studies. Distinction is made between guidelines pertaining to external network topology, analog measurements, data exchange, and implementation procedures. A philosophy and approach for constructing and testing external models is also ...

1996-05-01

119

Deep inelastic scattering of leptons on nuclei  

International Nuclear Information System (INIS)

Experimental studied of deep-inelastic scattering of neutrino, antineutrino, #mu#-mesons, electron reactions on He, D, Al, Fe, Au, Be, C, Ca, Ag, N nuclei conducted in recent years at different laboratories the world for consideration of modern status of the problems of R(x, Q"2) = #sigma#sub(L)/#sigma#sub(T) parameter variation and for study on nuclear effects in structural functions of nucleons are described in the review. Experimental information on measurements of the R parameter by data on EMS and SLAK groups is analyzed. It is noted that experimental data on measuring R contain essential errors that hampers unambiguous interpretation of data on nucleon structure. Present experimental data and predictions for explanation of the EMS effect are analyzed from the view point of quark and flucton models of a nucleus.

1984-06-19

120

A case-based approach to outpatient evaluation and management service coding.  

Science.gov (United States)

Understanding Center for Medicare and Medicaid Services (CMS) documentation and coding rules is challenging for most physicians. To accurately bill for clinical services, physicians must learn a system that may initially seem daunting, but is in fact governed by a small number of straightforward rules. The Evaluation and Management (E/M) guidelines for all service codes specify 3 components: history, examination, and medical decision-making, each with a defined set of elements or characteristics. Service coding is based on the level of care supported by the number of history and examination elements and the complexity of decision-making. This article will clarify the guidelines for outpatient clinical services and suggest a practical method of selecting appropriate E/M codes. Because physicians must often choose between billing codes 99213 and 99214 for a visit by an established patient, it will particularly focus on the minimum documentation ...

2008-11-01

121

Study on correlations of parameters of the optical potential of 38 MeV alpha particle elastic scattering on sup(68)Zn  

International Nuclear Information System (INIS)

Correlations of the Woods-Saxon four-parameter optical potential of scattering of 38 MeV #alpha# particles on sup(68)Zn have been analyzed. A search for discrete sets of potential parameters and functional ratios between different parameters is carried out.

122

Radionuclide X-ray fluorescence determination of Mn, Fe, Cu, Zn and Pb in wastewaters and sludges from wastewater treatment plants in Bratislava (SR)  

International Nuclear Information System (INIS)

Radiometric X-ray fluorescence analysis was used for the determination of Mn, Fe, Cu, Zn and Pb in wastewater and sludges from three wastewater treatment plants in Bratislava (SR). Metals were determined in wastewaters after preconcentration by 8-hydroxyquinoline and in sludges by drying and pressing to pellets. "2"3"8Pu and "1"0"9Cd was used for excitation of fluorescence radiation. (author).

1997-01-01

123

Radionuclide X-ray fluorescence determination of Cr, Fe, Cu, Zn,and Pb in industrial wastewaters after preconcentration of determined elements  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis was used for the determination of Cr, Fe, Cu, Zn and Ph in industrial wastewaters (from surface treatment of metals and glasses) after precipitation of determined elements by 8-hydroxyquinoline. (author).

1997-01-01

124

Materials design for semiconductor spintronics by ab initio electronic-structure calculation  

International Nuclear Information System (INIS)

A systematic study for the materials design of III-V and II-VI compound-based ferromagnetic diluted magnetic semiconductors is given based on ab initio calculations within the local spin density approximation. The electronic structures of 3d-transition-metal-atom-doped GaN and Mn-doped InN, InP, InAs, InSb, GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs and AlSb were calculated by the Korringa-Kohn-Rostoker method combined with the coherent potential approximation. It is found that the ferromagnetic ground states are readily achievable in V-, Cr- or Mn-doped GaN without any additional carrier doping treatments, and that InN is the most promising candidate for high-T_C ferromagnet. A simple explanation of the systematic behavior of the magnetic states in III-V and II-VI compound-based diluted magnetic semiconductors is also given. It is also shown that V or Cr-doped ZnS, ZnSe, and ZnTe are ferromagnetic without p- or n-type doping ...

2003-04-01

125

Influence of electric-field is on luminescence of ZnSe  

International Nuclear Information System (INIS)

The results of experimental researches of photoluminescence and X-ray luminescence in crystal ZnSe are presented at the different values of tension of electric-field to samples. Observed, that the electric field changes both intensity of stationary luminescence and form of bars in the spectrums of luminescence. At the saliatory change of difference of potentials on the electrodes of crystal in luminescence there are of long duration relaxation processes character of which substantially depends on the type of excitation of standard.

126

Effect of ultrasonic energy on Mn-Zn ferrite powder behavior  

Energy Technology Data Exchange (ETDEWEB)

Effect of ultrasonic-wave irradiation on the Mn-Zn ferrite powder suspension prepared by solid-state reaction and alcoholic dehydration methods was investigated. Size, distribution, and morphology of the powders prepared at different temperatures were examined, as a function of irradiation time. It was observed that the powders were reduced in size by ultrasonic energy through distinct routes. 8 refs., 7 figs., 1 tab.

1999-07-01

127

Dual Functions of ASCIZ in the DNA Base Damage Response and Pulmonary Organogenesis  

UK PubMed Central (United Kingdom)

Zn2+-finger proteins comprise one of the largest protein superfamilies with diverse biological functions. The ATM substrate Chk2-interacting Zn2+-finger protein...Full Text Available

2010-10-01

128

Determination of Mn, Fe, Ni, Cu, Zn and Pb contents in samples of apple trees by radionuclide X-ray fluorescence analysis  

Energy Technology Data Exchange (ETDEWEB)

The applicability of the radionuclide X-ray fluorescence analysis (RXFA) for qualitative and quantitative evaluation of environmental plant samples is discussed and examples of determination of Mn, Fe, Ni, Cu, Zn, Pb in samples of apple trees are given. The instrumentation, the standard and sample preparation are also presented.

1982-12-01

129

Determination of Fe and Zn in healing plants by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method was used for the determination of Fe and Zn in healing plants (Sage, Peppermint, Stinging, Common Agrimony, Milfoil, Ribwort, Tansy, White Dead-Nettle). "2"3"8Pu exciting source and Si/Li semiconductor detector were used for the determination. (author)

1999-06-01

130

Determination of Fe and Zn in agricultural plants with special cultivation by radionuclide x-ray fluorescence analysis  

International Nuclear Information System (INIS)

Fe and Zn were determined in various parts of maize (Zea mays) in dependence on quantity of organic substrate EKOFERT as organic fertilizer in soil, using radionuclide X-ray fluorescence analysis. The increase of quantity of organic substrate EKOFERT in soil causes a decrease of heavy metal concentrations in certain parts of the plant. (author). 4 refs., 1 tab.

1996-01-01

131

Determination of Cu, Ni, Zn and Pb contents in taraxacum officinale near the highway D-61 Bratislava-Trnava (SR) by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method with Si/Li semiconductor detector and "2"3"8Pu exciting source was used for the determination of Cu, Ni, Zn and Pb in plant samples (Taraxacum officinale) from various localities near the highway D-61 Bratislava-Trnava (SR). (author) 2 refs.; 1 fig.; 1 tab.

1993-12-01

132

Determination of Cu, Ni, Zn and Pb contents in soil near the D-61 Bratislava-Trnava Highway by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method with Si/Li semiconductor detector and "2"3"8Pu exciting source was used for the determination of Cu, Ni, Pb, and Zn in soil samples from various localities near the D-61 Bratislava-Trnava highway (CSFR). (author) 1 ref.; 1 tab.

1993-01-01

133

Studies on the electronic structure of some cubic intermetallic compounds of dysprosium following the self-consistent augmented-plane-wave method  

International Nuclear Information System (INIS)

The energy bands and the nature of the conduction electrons have been studied for two intermetallic compounds of dysprosium, i.e, DyZn and DyRh, following the self-consistent augmented-plane-wave (APW) method. The convergence of energy was found to be rapid for DyZn because the shell of 3d"1"0 electrons for Zn lies below the conduction band. The Fermi energies (E/sub F/) have been calculated to be 0.421 and 0.477 Ry for DyZn and DyRh, respectively. The densities and the numbers of conduction electrons inside and outside the APW spheres in each of these compounds are calculated, and it is shown that the character of conduction electrons inside the APW sphere of Dy is predominantly of d type. In order to see the accuracy of these results, self-consistent calculations were done for DyZn for different choices of the exchange potentials, and the calculated number of conduction electrons ...

134

Preparation of a "6"2Zn-"6"2Cu generator and of "6"1Cu following alpha particle irradiation of a nickel target  

International Nuclear Information System (INIS)

The "6"2Zn-"6"2Cu generator system is one of the few which yield a pure positron emitting daughter. The authors have developed a method for the preparation of this generator system following 32 MeV #alpha# particle bombardment of nickel targets. The chemical processing involves two stages: first a hydrous zirconium oxide column is used at pH 4-5 to separate the zinc and copper activities produced in the target nickel, and secondly, a conventional anion exchange column is used to retain the "6"2Zn and remove all copper activities in 2M HCl. This column serves as the "6"2Cu generator which will yield pure "6"2Cu repeatedly, free from "6"2Zn and other impurities, in a mixture of HCl and NaCl. A method is outlined also to obtain a solution of "6"2Zn using the hydrous zirconium oxide (HZO) column. "6"1Cu can be prepared as a by-product in the above procedure, but a method for the preparation of "6"1Cu alone ...

135

Phytoavailability and fractionation of copper, manganese, and zinc in soil following application of two composts to four crops  

International Nuclear Information System (INIS)

Two experiments were conducted to evaluate the effect of compost addition to soil on fractionation and bioavailability of Cu, Mn, and Zn to four crops. Soils growing Swiss chard (Beta vulgaris var. cicla L.) and basil (Ocimum basilicum L.) were amended (by volume) with 0, 20, 40, and 60% Source-Separated Municipal Solid Waste (SS-MSW) compost, and dill (Anethum graveolens L.) and peppermint (Mentha X piperita L.) were amended with 0, 20, 40, and 60% of high-Cu manure compost (by volume). The SS-MSW compost applications increased the concentration of Cu and Zn in all fractions, increased Mn in acid extractable (ACID), iron and manganese oxides (FeMnOX), and organic matter (OM) fractions, but decreased slightly exchangeable-Mn. Addition of 60% high-Cu manure compost to the soil increased Cu EXCH, ACID, FeMnOX, and OM fractions, but decreased EXCH-Mn, and did not change EXCH-Zn. Addition of both composts to soil reduced ...

2004-09-01

136

Elastic properties and structural studies on some zinc-borate glasses derived from ultrasonic, FT-IR and X-ray techniques  

International Nuclear Information System (INIS)

Glasses in the system (1 - x) [29Na2O- 4Al2O3- 67B2O3]- xZnO (0 ? x ? 35 mol%), have been prepared by the melt quenching technique. Elastic properties, X-ray and FT-IR spectroscopic studies have been employed to study the role of ZnO on the structure of the investigated glass system. Elastic properties and Debye temperature have been investigated using sound wave velocity measurements at 4 MHz at room temperature. The results showed that the density increases and the molar volume decreases while both sound velocities and the determined glass transition temperatures decrease with increase in x. X-ray and infrared spectra of the glasses reveal that the borate network consists of diborate units and is affected by the increase in the concentration of ZnO content. These results are interpreted in terms of the decrease in the N4 values (fraction of tetrahedral coordinated boron atoms), and substitution of longer bond lengths of ...

2009-05-05

137

Coaxial nanocables of p-type zinc telluride nanowires sheathed with silicon oxide: synthesis, characterization and properties  

International Nuclear Information System (INIS)

Coaxial nanocables with a single-crystalline zinc telluride (ZnTe) nanowire core and an amorphous silicon oxide (SiO_x) shell have been synthesized via a simple one-step chemical vapor deposition (CVD) method on gold-decorated silicon substrates. The single-crystal ZnTe nanowire core is in zinc-blende structure along the [111] direction, while the uniform SiO_x shell fully covers the core with no observable pin-hole or crack. Formation mechanisms of the ZnTe-SiO_x nanocables are discussed. The ZnTe nanowire core shows p-type electrical properties while the SiO_x shell acts as an effective insulating layer. The ZnTe-SiO_x nanocables may have potential applications in nanoscale devices, such as p-type FETs and nanosensors.

2009-11-11

138

The oxygenation of [3-methyl-3H]desacetoxycephalosporin C [7beta-(5-D-aminadipamido)-3-methylceph-3-em-4-carboxylic acid] to [3-hydroxymethyl-3H]desacetylcephalosporin C by 2-oxoglutarate-linked dioxygenases from Acremonium chrysogenum and Streptomyces clavuligerus.  

UK PubMed Central (United Kingdom)

Cell-free extracts of Acremonium chrysogenum and Streptomyces clavuligerus oxidize the 3-methyl group of desacetoxycephalosporin C to a 3-hydroxymethyl group. The enzyme responsible for this reaction...Full Text Available

1978-09-01

140

Production of three vector bosons in {gamma} {gamma} colliders; Producao de tres bosons vetoriais em {gamma} {gamma} colliders  

Energy Technology Data Exchange (ETDEWEB)

The production of three vector bosons in {gamma} {gamma} collisions studying the reactions {gamma} + {gamma} {yields} W{sup +} + W{sup -} + Z{sup 0} and {gamma} + {gamma} {yields} W{sup +} + W{sup -} + {gamma}. 12 refs., 4 figs., 2 tabs.

1994-12-31

141

Modalidade de morte em mamiferos expostos a irradiacao de corpo inteiro (sindrome aguda da radiacao). (Modes of death in mammals exposed to whole body radiation (acute radiation syndromes)).  

Science.gov (United States)

When an animal is exposed to a sufficient amount of radiation, there will be changes in many organs of the body, and as a result of either the effects in one particular organ or the interaction of effects in several organs, the animal as a whole will show...

1990-01-01

142

Electric loading of power transmission lines - statistical methodology and real time management; Carregamento eletrico de linhas de transmissao - metodologia estatistica e gerenciamento em tempo real  

Energy Technology Data Exchange (ETDEWEB)

This paper shows a computerized system, that adopt a statistical methodology and simultaneous measurements of wind velocity and environment temperature, as an experiences at the power transmission lines with environmental monitoring systems. 9 figs., 16 refs.

1991-12-31

143

Cumulative hadron production in quark models of flucton fragmentation  

International Nuclear Information System (INIS)

Quark models of cumulative particle production and EMS effect are analyzed. All the models are characterized by a universal relationship between the spectrum of cumulative nucleons and the cross section of cumulative particles containing valence nuclear quarks. This relationship is tested for a deuteron. The role is discussed played by secondary nuclear processes for heavy nuclei. A special role of ''sea'' cumulative particles (K"-, p-bar) is pointed out in understanding the nature of the difference between the structure functions of a nucleus and of free nucleon.

144

Corona effect in high voltage transmission lines; O efeito corona em linhas eletricas aereas de alta-tensao  

Energy Technology Data Exchange (ETDEWEB)

Corona from bare conductors of electrical overhead power lines is studied in this article. Its origin, as well as, its bad influences over communication systems are both studied, yet. Line`s models are defined, in order to be able the examination of Corona on line`s cables. Formulas for the surface electrical gradient calculations are shown. (author) 2 refs.

1993-12-01

145

Preparation of ZnO-Al2O3 Particles in a Premixed Flame  

DEFF Research Database (Denmark)

Zinc oxide (ZnO) and alumina (Al2O3) particles are synthesized by the combustion of their volatilized acetylacetonate precursors in a premixed air-methane flame reactor. The particles are characterized by XRD, transmission electron microscopy, scanning mobility particle sizing and by measurement of the BET specific surface area. Pure (?-)alumina particles appear as dendritic aggregates with average mobile diameter 43-93 nm consisting of partly sintered, crystalline primary particles with diameter 7.1-8.8 nm and specific surface area 184-229 m2/g. Pure zinc oxide yields compact, crystalline particles with diameter 25-40 nm and specific surface area 27-43 m2/g. The crystallite size for both oxides, estimated from the XRD line broadening, is comparable to or slightly smaller than the primary particle diameter. The specific surface area increases and the primary particle size decreases with a decreasing flame temperature and a decreasing precursor vapour pressure. The ...

2000-01-01

146

Nuclear radiation detectors on II-VI compounds  

International Nuclear Information System (INIS)

Nuclear radiation detectors in integral execution were produced by successive epitaxial growth from vapor phase of Zn Te and Cd Se thin layers onto scintillating Zn Se (Te) crystals. The irradiation of combined Zn Se (Te) - Zn Te - Cd Se detectors by Cu_K_a X-rays leads to the appearance of photoreceiver e.m.f., which tends to saturation with the increase of X-ray radiation dose reaching the value of 0.34-0.40 V at 200 R/min. The short circuit current dependence of irradiation dose power is linear. The matching factor for detectors with Zn Te-Cd Se photoreceivers with different doping levels is 0.68-0.92. The absolute monochromatic sensitivity is 0.32-0.35 m A/m W at a quantum efficiency 0.58-0.61 and a time constant 2 x 10"-"4 s. The calculated dose sensitivity for Zn Se(Te)-Zn Te-Cd Se combined detectors at the irradiation with X-rays ...

1993-10-13

147

Electrochemical and chemical dissolution behavior of Zn-Fe alloy coatings and its application to the analysis of Zn-Fe alloy layer. Zn-Fe kei mekki so no bunkyokuter dot yokai kyodo to teiryo bunseki eno oyo  

Energy Technology Data Exchange (ETDEWEB)

As surface treated steel sheets, steel sheets with Zn-Fe coatings as well as double-layer steel sheets with Fe-P alloy coatings on Zn-Fe alloy coatings are often used practically. Two treatment methods, which are used to dissolve only alloy layers without dissolving steel sheets in order to find amount and composition of alloy layersr have already been reported. This report investigates the mechanisms of these methods, particularly the mechanisms to control dissolution of steel sheets. In the alkali-dissolution method, Zn-Fe alloy coatings are dissolved in a strong alkaline solution(NaOH-triethanolamine (TEA)-H{sub 2}O{sub 2}). In this case, steel sheets are insoluble because passive films are formed on the surface. In the cathodic polarization electrolysis method, alloy layers are electrolyzed({minus}l.2V) and dissolved in an ammonium nitrate-0-phen electrolyte. At this potential, dissolution of steel sheets can be ...

1991-11-01

148

Cd(II), Pb(II) and Zn(II) removal from contaminated water by biosorption using activated sludge biomass  

Energy Technology Data Exchange (ETDEWEB)

Biosorption using activated sludge biomass (ASB) as a potentially sustainable technology for the treatment of wastewater containing different metal ions (Cd(II), Pb(II) and Zn(II)) was investigated. ASB metal uptake clearly competed with protons consumed by microbial biomass compared with control tests with non-activated sludge biomass. Biosorption tests confirmed maximum exchange between metal ions and protons at pH 2.0-4.5. It was revealed by the study that the amount of metal ions released from the biomass increased with biomass sludge concentration. The result showed that maximum absorption of metal ions was observed for Cd(II) at pH 3.5, Pb(II) at pH 4.0, and pH 4.5 for Zn(II) ions. The maximum absorption capacities of ASB for Cd(II), Pb(II) and Zn(II) were determined to be 59.3, 68.5 and 86.5%, respectively. The biosorption of heavy metals was directly proportional to ASB stabilization corresponding to a reduction in ...

2010-02-15

149

Thermoelectric properties of ZnO nanowires: A first principle research  

British Library Electronic Table of Contents (United Kingdom)

By means of ab-initio electronic structure calculation and one-dimensional Boltzmann transport equation solution, we investigate the size dependent thermoelectric (TE) properties of n-type ZnO nanowires (NWs) and surface passivation effects. As demonstrated by our calculations, largest figure of merit ZT achievable in thin NWs is larger than that in wide NWs, whereas being restrained by higher demand of n-type doping. Moreover, bare NWs are superior in TE application comparing with the passivated. To compete with conventional TE materials, lattice thermal conductivity of ZnO NWs should be at least 2 orders of magnitude lower than bulk value.

2011-01-01

150

Structural, electronic and optical properties of ZnX and CdX compounds (X = Se, Te and S) under hydrostatic pressure  

International Nuclear Information System (INIS)

The structural, electronic and optical properties of ZnX and CdX (X = Se, Te and S) are studied using density functional theory by the Wien2k package. The energy band gap, real and imaginary parts of the dielectric function, energy loss function, optical absorption coefficient and reflectivity spectra of these compounds are calculated. The Engel-Vosko approach improves the energy band gaps of ZnX and CdX compounds. The calculated optical parameters are in good agreement with available experimental results, particularly in the Engel-Vosko approach. Furthermore the effect of hydrostatic pressure on the energy band gap, the real and imaginary parts of the dielectric function of these compounds is studied. The first and second order pressure coefficient for the energy band gaps, the static dielectric function and the static reflectivity spectra are calculated.

2010-09-03

151

Seasonal variations of Zn, Cu, As and Mo in arsenic-rich stream at the Mokrsko gold deposit, Czech Republic  

British Library Electronic Table of Contents (United Kingdom)

Monthly sampling of slightly alkaline arsenic-rich stream in the Mokrsko gold deposit revealed seasonal variations in dissolved Zn, Cu, As and Mo. Concentrations of trace metal cations (Zn, Cu) increased as much as 330 and 178%, respectively, from minimum mean values at autumn to maximum mean values at spring. In contrast, concentrations of trace element oxyanions (As, Mo) revealed opposite seasonal pattern with increase to 189% (As) and 123% (Mo) during summer?autumn, indicating that in-stream biogeochemical process(es) played the main role in controlling the seasonal variations of these trace elements. The trace elements were mainly scavenged by low crystalline Mn oxyhydroxide and Fe oxyhydroxide (ferrihydrite). Results are consistent with sorption and coprecipitation processes controlli...

2011-01-01

152

Production of {sup 62}Zn, {sup 65}Zn and {sup 203}Pb radioisotopes for studying the transport of zinc and lead in plants  

Energy Technology Data Exchange (ETDEWEB)

In the Carpathian Basin, significant percentage of watershed area and floodplains of rivers are utilised agriculturally. Several potential sources of poisonous metal pollution have been identified in these areas. Because of spills from some of them a few severe accidents have happened especially in the watershed area of Tisza River during the last decades. The motivation of our present work was to produce {sup 62,65}Zn and {sup 203}Pb radioisotopes because they can be used especially as tracers for studying the kinetics of uptake, transport and accumulation of zinc and lead by plants under different circumstances. (orig.)

2004-07-01

153

Production of "6"2Zn, "6"5Zn and "2"0"3Pb radioisotopes for studying the transport of zinc and lead in plants  

International Nuclear Information System (INIS)

In the Carpathian Basin, significant percentage of watershed area and floodplains of rivers are utilised agriculturally. Several potential sources of poisonous metal pollution have been identified in these areas. Because of spills from some of them a few severe accidents have happened especially in the watershed area of Tisza River during the last decades. The motivation of our present work was to produce "6"2","6"5Zn and "2"0"3Pb radioisotopes because they can be used especially as tracers for studying the kinetics of uptake, transport and accumulation of zinc and lead by plants under different circumstances. (orig.)

154

Photoconductive ultraviolet detectors based on ZnO films  

British Library Electronic Table of Contents (United Kingdom)

Properties of photoconductive ultraviolet detectors fabricated on ZnO films were presented. Highly c-axis oriented ZnO films were grown on glass substrates by pulsed laser deposition. Ultraviolet photodetectors were fabricated based on metal-semiconductor-metal planar structures. The photoresponsivity and the quantum efficiency are much higher in the ultraviolet range than in the visible range, and the peak values are around 360nm. Photocurrent transients show that the detector has a large photocurrent with the peak value of 2.8mA, and a slow photoresponse with a rise time of 5min and a decay time of 7min. The response curve of the detector is fitted well with exponential curve. The large photocurrent should result from the both effects of the accumulation of conduction electrons and the d...

2006-01-01

155

Oxygen reduction reaction on electrodeposited zinc oxide electrodes in KCl solution at 70 deg. C  

Energy Technology Data Exchange (ETDEWEB)

The reduction of oxygen was studied in 0.1 M KCl at 70 deg. C using the rotating disk electrode (RDE) technique on platinum and electrodeposited ZnO thin film electrodes deposited on platinum substrates. In the absence of Zn{sup 2+} ions in solution, a Tafel slope of 139 mV dec{sup -1} was obtained, a value close to that measured on bare platinum electrode (133 mV dec{sup -1}) and ascribed to the limitation of the reaction rate by the first electron transfer. The main difference between the noble metal and the oxide electrode was a shift of the curves towards more negative potentials. In the presence of Zn{sup 2+} ions, the current density decreased significantly and the Tafel slope was measured at 282 mV dec{sup -1} showing that the electrode was partially blocked by zinc oxide formation reaction intermediates.

2006-04-01

156

Mathematical modeling of a primary zinc/air battery  

Energy Technology Data Exchange (ETDEWEB)

This paper reports on the mathematical model developed by Sunu and Bennion that has been extended to include the separator, precipitation of both solid ZnO and K{sub 2}Zn(OH){sub 4}, and the air electrode, and has been used to investigate the behavior of a primary Zn-Air battery with respect to battery design features. Predictions obtained from the model indicate that anode material utilization is predominantly limited by depletion of the concentration of hydroxide ions. The effect of electrode thickness on anode material utilization is insignificant, whereas material loading per unit volume has a great effect on anode material utilization; a higher loading lowers both the anode material utilization and delivered capacity. Use of a thick separator will increase the anode material utilization, but may reduce the cell voltage.

1992-04-01

157

Magnetic properties of B and AB-spinels Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Ni, Mg) materials  

Energy Technology Data Exchange (ETDEWEB)

The magnetic properties of diluted spinels Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Mg, Ni) systems have been studied by mean field theory, probability law and high-temperature series expansions method in the range 0 {<=} x {<=} 1. The exchange interactions are calculated by the first and second theory, respectively. The magnetic phase diagrams of Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Mg, Ni) are calculated by the high-temperature series expansions, combined with the Pade approximants method. The critical exponent associated with the magnetic susceptibility ({gamma}) is deduced.

2010-08-06

158

Enhanced inactivation of bacteria by metal-oxide nanoparticles combined with visible light irradiation  

British Library Electronic Table of Contents (United Kingdom)

AbstractBackground In recent years nano-metaloxides which easily penetrate into the cells with special interest due to their higher chemical reactivity as compared to that of similar materials in the bulk form. Of particular interest are nano-TiO2 and ZnO, which have been widely used for their bactericidal and anticancerous properties. Purpose The aim of the present study was to examine the bactericidal properties of nano-TiO2 and ZnO combined with visible light on S. aureus and S. epidermitis, known for their high prevalence in infected wounds. Study Using the technique of electron-spin resonance (ESR) coupled with spin trapping, we examined the ability of TiO2 and ZnO nanoparticle suspensions in water to produce reactive oxygen species (ROS) with and without visible light irradiation. Th...

2011-01-01

159

Effects of Copper, Cadmium, and Zinc on the Hatching Success of Brine Shrimp (Artemia franciscana)  

British Library Electronic Table of Contents (United Kingdom)

Previous studies indicate that the hatching success of brine shrimp (Artemia franciscana) cysts is surprisingly sensitive to ambient metal concentrations. These studies estimated median effective concentrations (EC50s) of 7, 5, and 28??g l?1 for Cd, Cu, and Zn, suggesting that the hatching end point for A. franciscana is the most sensitive tested to date for Cd and Zn in saline environments and comparable in sensitivity with the most sensitive tested to date for Cu. Furthermore, these data suggest that brine shrimp are at significant risk from Cu and Zn in Great Salt Lake (GSL), UT, where ambient concentrations as high as 10 and 14??g l?1, respectively, have been measured. Given that brine shrimp appear to be successfully reproducing in GSL, we hypothesized that these toxicity values were ...

2006-01-01

160

Dielectric behaviour of emeraldine base polymer?ZnO nanocomposite film in the low to medium frequency  

British Library Electronic Table of Contents (United Kingdom)

Emeraldine base (EB) polymer?ZnO nanoparticles composite films has been synthesized by solution casting technique on ITO-coated glass substrate and characterized by XRD, FTIR and TEM for their structure and morphology. Dielectric behaviour of these composite films has been investigated in the very low frequency region to medium frequency region (1?kHz?1?MHz). The dielectric constant of the composite with 30% nanoparticles is almost one-tenth of the pure EB. The dielectric value becomes constant in the frequency region greater than 400?kHz. The change in dielectric behaviour of the composite is explained on the basis of multilayered interface formed between the ZnO nanoparticles and emeraldine chains. Nanoparticles have high energy surface which is responsible for the decrease of free volum...

2011-01-01

161

Determination of selected microelements in polish herbs and their infusions  

Energy Technology Data Exchange (ETDEWEB)

Ba, Cd, Cr, Cu, Fe, Ni, Pb and Zn were determined in birch leaves (Folium Betulae), dandelion roots (Radix Taraxacae), hawthorn blossom (Inflorescentia Crataegi) and their infusions by graphite furnace atomic absorption spectrometry (GFAAS) after microwave digestion of plant samples. Infusions were made from herbs according to prescription for patients, provided by the producer of medicine on the package. The results obtained were compared with daily requirements for each element. Results show high content of cadmium in the medicinal plants analyzed. The highest level in infusions was observed for Ni and Zn (over 90% of the total element concentration for Ni and in most cases over 50% for Zn), and the lowest for Cd and Pb. The calculated daily intake of majority of the analyzed elements was very low (under 1% of daily requirements)

2007-08-01

162

Biodynamic modelling of the accumulation of Ag, Cd and Zn by the deposit-feeding polychaete Nereis diversicolor: Inter-population variability and a generalised predictive model  

British Library Electronic Table of Contents (United Kingdom)

Biodynamic parameters of the ragworm Nereis diversicolor from southern Spain and south England were experimentally derived to assess the inter-population variability of physiological parameters of the bioaccumulation of Ag, Cd and Zn from water and sediment. Although there were some limited variations, these were not consistent with the local metal bioavailability nor with temperature changes. Incorporating the biodynamic parameters into a defined biodynamic model, confirmed that sediment is the predominant source of Cd and Zn accumulated by the worms, accounting in each case for 99% of the overall accumulated metals, whereas the contribution of dissolved Ag to the total accumulated by the worm increased from about 27 to about 53% with increasing dissolved Ag concentration. Standardised va...

2010-01-01

163

A novel electrochemical alkylation of aniline with methanol over Zn/Cu salts modified kaolin  

British Library Electronic Table of Contents (United Kingdom)

A novel liquid phase alkylation of aniline with methanol over Zn/Cu salts modified kaolin assisted with a pair of porous carbon electrode in slurry-bed reactor under constant current intensity, room temperature and atmospheric pressure was reported. The Zn/Cu salts modified kaolin catalysts were synthesized and characterized by infrared spectrometer (IR), powder X-ray diffraction (XRD) and scanning electron microscopy (SEM), which showed that the transition metals were completely supported on kaolins structure and formed a pored one. The effect parameters, such as initial pH, electrolysis time, metal ratio with kaolin and salts composition in this electrochemical catalytic system, were studied. The procedure was inspected by ultraviolet-visible spectrum (UV-vis), and the product distributi...

2008-01-01

165

Semiconductor Radiation Detectors with Frisch Collars and Collimators for Gamma Ray Spectroscopy and Imaging  

Energy Technology Data Exchange (ETDEWEB)

To study CdZnTe as a high energy resolution gamma ray detector with a novel new design, and to build a detector array from the new detector design

2006-12-04

166

Rhizosphere Acidification by Iron Deficient Bean Plants: The Role of Trace Amounts of Divalent Metal Ions  

UK PubMed Central (United Kingdom)

Rhizosphere acidification by Fe-deficient bean (Phaseolus vulgaris L.) plants was induced by trace amounts of divalent metal ions (Zn, Mn). The induction of this Fe-efficiency reaction...Full Text Available

1989-05-01

167

Photoconductive ultraviolet detectors based on ZnO films  

Energy Technology Data Exchange (ETDEWEB)

Properties of photoconductive ultraviolet detectors fabricated on ZnO films were presented. Highly c-axis oriented ZnO films were grown on glass substrates by pulsed laser deposition. Ultraviolet photodetectors were fabricated based on metal-semiconductor-metal planar structures. The photoresponsivity and the quantum efficiency are much higher in the ultraviolet range than in the visible range, and the peak values are around 360 nm. Photocurrent transients show that the detector has a large photocurrent with the peak value of 2.8 mA, and a slow photoresponse with a rise time of 5 min and a decay time of 7 min. The response curve of the detector is fitted well with exponential curve. The large photocurrent should result from the both effects of the accumulation of conduction electrons and the decrease of the barrier height between crystallites. The relaxation time constant {tau} obtained from the curve fitting represents the time accumulation ...

2006-12-15

168

Photoconductive ultraviolet detectors based on ZnO films  

International Nuclear Information System (INIS)

Properties of photoconductive ultraviolet detectors fabricated on ZnO films were presented. Highly c-axis oriented ZnO films were grown on glass substrates by pulsed laser deposition. Ultraviolet photodetectors were fabricated based on metal-semiconductor-metal planar structures. The photoresponsivity and the quantum efficiency are much higher in the ultraviolet range than in the visible range, and the peak values are around 360 nm. Photocurrent transients show that the detector has a large photocurrent with the peak value of 2.8 mA, and a slow photoresponse with a rise time of 5 min and a decay time of 7 min. The response curve of the detector is fitted well with exponential curve. The large photocurrent should result from the both effects of the accumulation of conduction electrons and the decrease of the barrier height between crystallites. The relaxation time constant #tau# obtained from the curve fitting represents the time accumulation ...

2006-12-15

169

Performance of ZnMoO4 crystal as cryogenic scintillating bolometer to search for double beta decay of molybdenum  

CERN Document Server

Zinc molybdate (ZnMoO4) single crystals were grown for the first time by the Czochralski method and their luminescence was measured under X ray excitation in the temperature range 85-400 K. Properties of ZnMoO4 crystal as cryogenic low temperature scintillator were checked for the first time. Radioactive contamination of the ZnMoO4 crystal was estimated as <0.3 mBq/kg (228-Th) and 8 mBq/kg (226-Ra). Thanks to the simultaneous measurement of the scintillation light and the phonon signal, the alpha particles can be discriminated from the gamma/beta interactions, making this compound extremely promising for the search of neutrinoless Double Beta Decay of 100-Mo. We also report on the ability to discriminate the alpha-induced background without the light measurement, thanks to a different shape of the thermal signal that characterizes gamma/beta and alpha particle interactions.

2010-01-01

170

Metal atom diffusion in amorphous silica and at the silica surface. Progress report, December 1, 1982-December 1, 1983  

Energy Technology Data Exchange (ETDEWEB)

Objective is to study the effects of local structure, interatomic forces, and atom size on the mobility of metal atoms in amorphous silica and at the silica surface. EXAFS studies of Zn and Pt in silica are reported. (DLC)

1983-01-01

172

Lattice W_N algebra and its quantization  

International Nuclear Information System (INIS)

We consider the integrable structure of the quantum lattice W_N algebras. We introduce the ultralocal Lax matrix, and show that the Yang-Baxter relation is satisfied with a Z_N invariant R-matrix. (orig.).

1997-11-01

173

German connections behind EFL's Zn-air  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a new concept in zinc-air battery technology and provides and insight into the role of the German Post Office and its former chairman in its commercial promotion. (UK)

1994-10-01

174

Evolution of defect structures during cold rolling of ultrafine-grained Cu and Cu-Zn alloys: Influence of stacking fault energy  

Energy Technology Data Exchange (ETDEWEB)

Samples of pure Cu, bronze (Cu-10 wt.% Zn) and brass (Cu-30 wt.% Zn) with stacking fault energies (SFE) of 78, 35, and 14 mJ/m{sup 2}, respectively, were processed by high-pressure torsion (HPT) and by a combination of HPT followed by cold-rolling (CR). X-ray diffraction measurements indicate that a decrease in SFE leads both to a decrease in crystallite size and to increases in microstrain, dislocation and twin densities for the HPT and HPT + CR processed ultrafine-grained (UFG) samples. Compared with processing by HPT, subsequent processing by CR refines the crystallite size of all samples, increases the twin densities of UFG bronze and brass, and increases the dislocation density in UFG bronze. It also decreases the dislocation density in UFG brass and leads to an unchanged dislocation density in UFG copper. The results suggest there may be an optimum stacking fault energy for dislocation accumulation in UFG Cu-Zn alloys ...

2008-02-15

175

Epigallocatechin-3-gallate affects the growth of LNCaP cells via membrane fluidity and distribution of cellular zinc*  

UK PubMed Central (United Kingdom)

Objective: To evaluate effects of epigallocatechin-3-gallate (EGCG) on the viability, membrane properties, and zinc distribution, with and without the presence of Zn2+, in human prostate...Full Text Available

2009-06-01

176

Economic evaluation of the solar thermal co-production of zinc, synthesis gas, and hydrogen  

Energy Technology Data Exchange (ETDEWEB)

The use of concentrated solar energy for co-producing Zn and synthesis gas from Zn O and natural gas upgrades the calorific value of the initial reactants by 39% and, when compared to the traditional carbothermic reduction of Zn O, has the potential of reducing CO{sub 2} emissions by up to 78%. An economic assessment for an industrial thermochemical plant, 30 to 51 MW solar input, indicates that the cost of solar production of zinc ranges between 89-133 $/t (excluding the cost of Zn O feed and credit for pollution abatement), and thus might be competitive with conventional fossil-fuel-based processes at current fuel prices. The cost of solar H{sub 2}, produced by splitting water with zinc, is estimated to be in the range 0.10-0.14 $/kWh, and it is a favorable long term prospect once the cost of energy will account for the environmental externalities from fossil fuel burning such as the costs for CO{sub ...

1999-08-01

177

Co-precipitated ZnAl2O4 spinel precursor as potential sintering aid for pure alumina system  

British Library Electronic Table of Contents (United Kingdom)

Ultra-fine ZnAl2O4 spinel hydrogel precursor synthesized from mixed salt solutions of Zn^2^+ and Al^3^+ ions using ammonium hydroxide-hexamethylenetetramine as basic media for co-precipitation was used as bonding material and sintering aid for pure alumina system. The hydrogel powder exhibited some well-defined ZnAl2O4 spinel phases at 800^oC. Alumina compacts were fabricated by incorporating small proportions of the precursor in alumina powder and firing at different temperatures (1350-1500^oC). The degree of densification was studied by measurement of fired shrinkage, apparent porosity, bulk density and cold crushing strength. Phase compositions and microstructural features of sintered samples were evaluated by XRD and SEM respectively. Addition of 0.2% hydrogel powder to alumina exhibit...

2010-01-01

178

CdS and ZnS quantum dots embedded in hyaluronic acid films  

Energy Technology Data Exchange (ETDEWEB)

An in situ synthesis of ZnS and CdS quantum dots (QDs) in an aqueous solution of sodium hyaluronate (Hyal) produced foils emitting light on excitation with a UV light. The wavelength of emission was only slightly QDs size and more QDs concentration dependent and reached up to {approx}320 nm in the case of ZnS and {approx}400-450 nm in the case of CdS. Nanoparticles remained as non-agglomerated 10-20 nm nanoclusters. CdS/Hyal and ZnS/Hyal-QDs biocomposites were characterized using photoluminescence (PL), IR spectrometric techniques, and Transmission Electron Microscopy (TEM). The absolute molecular weights, radii of gyration, R{sub g}, and thermodynamic properties of the obtained foils are given. Electric resistivity studies performed for the hyaluronic foil in the 100-1000 V range have revealed that the hyaluronate foil has very weak conducting properties and QDs only insignificantly affect those properties as QDs ...

2009-07-29

179

Zn/gelled 6M KOH/O{sub 2} zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

The gel electrolyte for the zinc-air cell was prepared by mixing hydroponics gel with a 6M potassium hydroxide aqueous solution. The self-discharge of cells was characterized by measuring the open-circuit voltage. The effect of a discharge rate of 50mA constant current on cell voltage and plateau hour, as well as the voltage-current and current density-power density were measured and analysed. The electrode degradation after discharge cycling was characterized by structural and surface methods. The oxidation of the electrode surface further blocked the utilization of the Zn anode and was identified as a cause for the failure of the cell. (author)

2006-09-13

180

Structural Phase Transition in AuZn Alloys  

Energy Technology Data Exchange (ETDEWEB)

AuxZn1-x alloys undergo a shape memory martensitic transformation whose temperature and nature (continuous or discontinuous) is strongly composition dependent. Neutron diffraction experiments were performed on single crystals of x=50 and 52 to explore the structural changes occurring at the transition temperature. A transverse modulation with wavevector q0=(1/3,1/3,0) develops below the transition temperature, with no observable change in lattice parameter. However, the Bragg peak width shows a broadening suggesting an unresolved rhombohedral distortion similar to what has been observed in NiTi-Fe alloys.

2009-05-03

181

Progress towards a 20 Ah/12 V zinc/air battery  

Energy Technology Data Exchange (ETDEWEB)

Electrode areas, for the bifunctional O{sub 2}-electrodes and the pasted Zn-electrodes, have been successfully scaled up from 25 cm{sup 2} up to 250 cm{sup 2}. A filter press type cell was used to measure the cycle life of larger electrodes (100 cm{sup 2}). Up to now, more than 100 charge-discharge cycles (900 hours) with these scaled up Zn/O{sub 2}-cells could be demonstrated. (author) 2 figs., 2 refs.

1997-06-01

182

Multielement XRF-analysis of blood from patients with dilated cardiomyopathy  

International Nuclear Information System (INIS)

Radionuclide x-ray fluorescence analysis was used for the determination of Fe, Zn, Br and Rb levels in whole blood from dilated cardiomyopathy patients and from a control group. The XRF-system consisted of a radionuclide source "1"0"9Cd, a semiconductor Si/Li detector connected to a multichannel analyzer. Fe content in blood of patients was significantly lower than that of the control. Zn content showed no deviation from normal range. Values for Br and Rb in patients highly exceed the range reported for them. (author) 4 tabs.; 9 refs.

1991-03-01

183

Identification of elements in plant drugs and their water infusion using X-ray fluorescence analysis  

International Nuclear Information System (INIS)

The present work gives preliminary results of analysis of drug mixtures (NEPHROSAL tea bag) and its water infusion. In a sample of dried drugs the elements K, Ca, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Pb were identified, whereas in their water infusion only Ca, Mn, Zn and Sr were found. The method applied was radionuclide X-ray fluorescence analysis using a radionuclide source "1"0"9Cd, a Si/Li semiconductor detector and a multichannel analyzer Canberra 8100. (author) 6 refs.; 3 figs.

8100-01-01

184

Effect of Inner Electrode on Electrical Properties of (Zn,Mg)TiO3-Based Multilayer Ceramic Capacitor  

Science.gov (United States)

In this study, different proportions of silver-palladium alloy used as an inner electrode are adopted to fabricate (Zn,Mg)TiO3-based multilayer ceramic capacitors. Effects of sintering temperature, and measuring frequency on the dielectric properties of the samples with different proportions of the Pd-Ag inner electrode are investigated. The continuity of the inner electrode and the proportion of Pd-Ag of the inner electrode of samples sintered at different temperatures play important roles in determining the dielectric properties.

2005-12-01

185

Determination of Mn, Fe, Cu, Zn, and Pb in particulate matter, raw and final materials of a brick factory by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method with a Si/Li semiconductor detector and "2"3"8Pu exciting source was used in the study of Mn, Fe, Cu, Zn, and Pb content of solid emissions, raw and final materials of a brick factory. From the point of view of metal content, the working environment if the brick factory is safe for workers. (author) 2 refs.; 2 figs.; 1 tab.

1994-01-01

186

Depleted zinc: Properties, application, production  

Energy Technology Data Exchange (ETDEWEB)

The addition of ZnO, depleted in the Zn-64 isotope, to the water of boiling water nuclear reactors lessens the accumulation of Co-60 on the reactor interior surfaces, reduces radioactive wastes and increases the reactor service-life because of the inhibitory action of zinc on inter-granular stress corrosion cracking. To the same effect depleted zinc in the form of acetate dihydrate is used in pressurized water reactors. Gas centrifuge isotope separation method is applied for production of depleted zinc on the industrial scale. More than 20 years of depleted zinc application history demonstrates its benefits for reduction of NPP personnel radiation exposure and combating construction materials corrosion.

2009-07-15

187

Absolute, cascade-free cross sections for the "2S#->#"2P transition in Zn"+ using electron-energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Absolute, cascade-free excitation cross sections in an ion have been measured for the resonance "2S#->#"2P transition in Zn"+ using electron-energy-loss and merged electron-ion beams methods. Measurements were carried out at electron energies of below threshold to 6 times threshold. Comparisons are made with 2-, 5-, and 15-state close-coupling and distorted-wave theories. There is good agreement between experiment and the 15-state close-coupling cross sections over the energy range of the calculations.

188

Solution and particle effects on the biosorption of heavy metals by seaweed biomass  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of cadmium (Cd), cobalt (Co), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) by six fractions of particle sizes, ranging from 0.063 to 1.4 mm of dry marine algal biomass of Sargassum fluitans and Ascophyllum nodosum, is examined. Equilibrium metal uptake by larger particles was higher than that by smaller particles in the order of Pb > Cd > Cu > Co > Zn > Ni for both biomass types, with S. fluitans sorbing slightly more than A. nodosum. Uptakes of metals ranged from the highest, q{sub max} = 369 mg Pb/g (particle size 0.84-1.00 mm), to the low Zn and Ni uptakes, q{sub max} = 77 mg/g (size 0.84-1.00 mm) for S. fluitans. A. nodosum adsorbed metals in the range from q{sub max} = 287 mg Pg/g (particle size 0.84-1.00 mm) to q{sub max} = 73 mg Zn/g (particle size 0.84-1.00mm). Harder stipe fractions of S. fluitans demonstrated generally higher metal uptakes than the softer ...

1996-12-01

189

The Muhlbauer method for pipeline risk management in onshore environment; O metodo de Muhlbauer para gerenciamento de risco em linhas de dutos em ambiente 'onshore'  

Energy Technology Data Exchange (ETDEWEB)

There are several methods for the risk assessment and risk management applied to pipelines, among them the Muhlbauer's Method. W. Kent Muhlbauer is an internationally recognized authority on pipeline risk management. He made a detailed identification about 300 distinct conditions that influence the risk assessment in pipelines and he proposed a score system that is known as method of Muhlbauer. The purpose of this model is to evaluate the public exposure to the risk and identify ways for management that risk in fact. The assessment is made by the attribution of quantitative values to the several items that influences in the pipeline risk. This paper approaches the Muhlbauer's basic model for risk assessment and management in pipelines. In the beginning, the basic model for risk assessment is presented, and methodology for pipelines in onshore environment is detailed. After, presents major items in risk assessment and this relative score. Finally, present the ...

2008-07-01

190

Pressure based leak detection system implanted on the business Unit Exploration and Production of PETROBRAS in Rio Grande do Norte e Ceara; Sistema de deteccao de vazamentos em dutos baseado em pressao implantado na Unidade de Negocios de Exploracao e Producao da PETROBRAS no Rio de Grande do Norte e Ceara  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the experience faced by people who works in PETROBRAS Business Unit (UN-RNCE), located in Rio Grande do Norte Province, Brazil, during the implementation of a pipeline leak detection system. That application involved nine multiphase oil pipelines distributed along several production facilities. Because of the emergency after the leakage that polluted the Guanabara bay and due to the two phases and multi phases pipelines characteristics, the UN-RNCE decided to apply the Pressure Point Analysis (PPA) technology in order to detect leakages. It is a statistical method for leak detection e uses a very simple instrumentation which facilitates the installation and maintenance. However, in order to get the best performance of the system, it is necessary to know thoroughly the whole process and have a fast and reliable SCADA system for long distance communication. Finally it will be shown the test results, the recommendations to expand the system and the conclusions. ...

2003-07-01

191

Observational approach implementation guidance: Year-end report  

Energy Technology Data Exchange (ETDEWEB)

It is generally recognized that the Remedial Investigation/Feasibility Study (RI/FS) process can be time-consuming and costly. To expedite the process, the Environmental Protection Agency, through the National Contingency Plan and Office of Solid Waste and Emergency Response (OSWER) Directives, has promoted streamlining'' the RI/FS. The concept of streamlining is directly applicable to Resource Conservation and Recovery Act (RCRA) Remedial Facility Investigation/Corrective Measure Study (RFI/CMS) as well. The US Department of Energy's (DOE's) environmental restoration process promises to be lengthy and expensive: therefore, the Office of Environmental Restoration (EM-40) believes that it is to incorporate streamlining into RI/FS and RFI/CMS efforts across the DOE complex. The Office of Program Support (EM-43) has asked Pacific Northwest Laboratory (PNL) to provide presentations and workshops on streamlining ...

1992-06-01

192

Integrated thermal and nonthermal treatment technology and subsystem cost sensitivity analysis  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy`s (DOE) Environmental Management Office of Science and Technology (EM-50) authorized studies on alternative systems for treating contact-handled DOE mixed low-level radioactive waste (MLLW). The on-going Integrated Thermal Treatment Systems` (ITTS) and the Integrated Nonthermal Treatment Systems` (INTS) studies satisfy this request. EM-50 further authorized supporting studies including this technology and subsystem cost sensitivity analysis. This analysis identifies areas where technology development could have the greatest impact on total life cycle system costs. These areas are determined by evaluating the sensitivity of system life cycle costs relative to changes in life cycle component or phase costs, subsystem costs, contingency allowance, facility capacity, operating life, and disposal costs. For all treatment systems, the most cost sensitive life cycle phase is the operations and maintenance phase and the ...

1997-02-01

193

Integrated EM & Thermal Simulations with Upgraded VORPAL Software  

Energy Technology Data Exchange (ETDEWEB)

Nuclear physics accelerators are powered by microwaves which must travel in waveguides between room-temperature sources and the cryogenic accelerator structures. The ohmic heat load from the microwaves is affected by the temperature-dependent surface resistance and in turn affects the cryogenic thermal conduction problem. Integrated EM & thermal analysis of this difficult non-linear problem is now possible with the VORPAL finite-difference time-domain simulation tool. We highlight thermal benchmarking work with a complex HOM feed-through geometry, done in collaboration with researchers at the Thomas Jefferson National Accelerator Laboratory, and discuss upcoming design studies with this emerging tool. This work is part of an effort to generalize the VORPAL framework to include generalized PDE capabilities, for wider multi-physics capabilities in the accelerator, vacuum electronics, plasma processing and fusion R&D fields, and we will also discuss user ...

2011-03-01

194

Implementation of the DOE Office of Technology Development Strategic Program Plan for Environmental Education and Development  

Energy Technology Data Exchange (ETDEWEB)

With the November 1989 formation of the Office of Technology Development (OTD) within the Office of Environmental Restoration and Waste Management (EM) came the responsibility to develop programs to ensurethat enough trained and educated people would be available to support the achievement of EM's 30-year goal. This mission responsibility derives from public policy and Departmental environmental management requirements. Within DOE, urgency to move forward resulted from the assumptions (1) that the current workforce was insufficiently prepared for the transition from a production mission to a mission of environmental compliance and cleanup; and (2) that, given current trends and forecasts, the national education infrastructure was unlikely to yield the scientists, engineers, and technicians to meet future DOE workforce needs, especially in the case of women and minorities who, projected to make up two-thirds of the net entering ...

1992-01-01

195

Electron momentum spectroscopy of H_2 and D_2: Ionization to ground and excited final states  

International Nuclear Information System (INIS)

The symmetric noncoplanar (e,2e) cross sections (momentum profiles) of H_2 and D_2 for the transitions to the 2p#sigma#_u and 2s#sigma#_g excited ion states have been measured, relative to the ground-state ion transition, using a high-sensitivity multichannel momentum-dispersive electron momentum spectrometer (EMS) at an impact energy of 1200 eV. Newly calculated plane-wave impulse approximation (PWIA) cross sections, based on a full-configuration-interaction H_2 wave function, are compared to the experimental results. These calculations are in better agreement with the experimental results for the transition to the 2s#sigma#_g ion state than the earlier theoretical work of Liu and Smith, Jr. [Phys. Rev. A 31, 3003 (1985)] which has been found to be in error. Nevertheless, significant discrepancies between the relative experimental and theoretical cross sections are observed for the transitions to excited ion states, suggesting a failure of the PWIA description of ...

196

EMS network security applications of the future  

Energy Technology Data Exchange (ETDEWEB)

Changes facing the electricity supply industry are significant, and the challenges these changes pose are enormous. There are major changes to the business environment of transitional electric utilities. There are also changes in the management of the companies in that nontechnical people are taking over the leadership of traditionally technical companies to deal with the new business scenario. This raises the concern that there may be a lack of familiarity by management of the technical issues involved with the result that the quality of the product may be at risk over the long term. This article deals with the future. It describes a vision for the control center energy management systems (EMS) network security applications as a function of the current and expected changes in the electric supply industry. The objective is to present a conceptual specification. It suggests possible approaches to the problems control centers are likely to encounter in the future. ...

1996-04-01

197

Correlation between designed wall thickness of gas pipelines and external and internal corrosion processes; Adequacao de espessura de parede projetada em funcao de processos de corrosao externa e interna em gasodutos  

Energy Technology Data Exchange (ETDEWEB)

Corrosion control on gas pipelines plays an important role on the assessment of pipeline integrity and reliability. In many countries a great extension of buried pipelines is used on transport and distribution systems. This extension will be certainly increased in a near future due to the increasing consumption of natural gas. Inadequate corrosion control can drive to pipeline failures, bringing up the possibility of accidents in populated or environmental protected areas, bringing together severe economical, legal and environmental consequences. Corrosion is frequently considered as a natural and inevitable phenomenon. Based upon this assumption, some recommendations are included on design standards of gas pipelines in order to compensate its detrimental effect. The aim of this work is to present a review of the correlation between external corrosion process and the guidelines established during the project phase of gas pipelines. It is intended to contribute for a better ...

2004-07-01

198

Collective behavior of stock price movements in an emerging market  

CERN Document Server

To investigate the universality of the structure of interactions in different markets, we analyze the cross-correlation matrix ${\\mathbf C}$ of stock price fluctuations in the National Stock Exchange (NSE) of India. We find that this {\\em emerging} market exhibits strong correlations in the movement of stock prices compared to {\\em developed} markets, such as the New York Stock Exchange (NYSE). This is shown to be due to the dominant influence of a common market mode on the stock prices. By comparison, interactions between related stocks, e.g., those belonging to the same business sector, are much weaker. This lack of distinct sector identity in emerging markets is explicitly shown by reconstructing the network of mutually interacting stocks. Spectral analysis of ${\\mathbf C}$ for NSE reveals that, the few largest eigenvalues deviate from the bulk of the spectrum predicted by random matrix theory, but they are far fewer in number compared ...

2007-01-01

199

A Wide-Band Electromagnetic Impedance Profiling System forNon-Invasive Subsurface Characterization  

Energy Technology Data Exchange (ETDEWEB)

A non-invasive, wide-band electromagnetic (EM) impedance difference system for shallow subsurface electrical structure characterization in environmental and engineering problems has been developed at the Lawrence Berkeley National Laboratory (LBNL). Electrical parameters of interest are electrical conductivity and dielectric permittivity that are deduced from the impedance difference data. The prototype system includes a magnetic loop transmitter, which operates between 0.1 MHz and 100 MHz, an electrical dipole antenna for observing the electric field, and a loop antenna for measuring the magnetic field.All antennas are mounted on a cart made of non-metallic material for easy movement of the whole array for profiling. Surface EM impedance difference is obtained by taking the difference of the ratios of the electric fields to the magnetic fields at selected frequencies at two different levels. Numerical simulations will be presented to verify ...

2004-12-17

200

Ultraviolet Complete Electroweak Model Without a Higgs Particle  

CERN Document Server

An electroweak model with running coupling constants described by an energy dependent entire function is utraviolet complete and avoids unitarity violations for energies above 1 TeV. The action contains no physical scalar fields and no Higgs particle and the physical electroweak model fields are local and satisfy microcausality. The $W$ and $Z$ masses are compatible with a symmetry breaking $SU(2)_L\\times U(1)_Y \\rightarrow U(1)_{\\rm em}$, which retains a massless photon. The vertex couplings possess an energy scale $\\Lambda_W > 1$ TeV predicting scattering amplitudes that can be tested at the LHC.

2010-01-01

201

The AMS-02 electromagnetic calorimeter  

CERN Document Server

The Electromagnetic Calorimeter (ECAL) of the AMS-02 experiment is a lead-scintillating fibers sampling calorimeter characterized by high granularity that allows to image the longitudinal and lateral showers development, a key issue to provide high electron/hadron discrimination. The light collection system and the FE electronics are designed to let the calorimeter operate over a wide energy range from few GeV up to 1 TeV. A full-scale prototype of the e.m. calorimeter was tested at CERN in October 2001 using electrons and pions beams with energy ranging from 3 to 100 GeV. Effective sampling thickness, linearity and energy resolution were measured. (8 refs).

2002-01-01

202

Ten-nanometer surface intrusions in room temperature silicon  

CERN Document Server

Defects ~10 nm in size, with number densities ~10^{10} cm^{-2}, form spontaneously beneath ion-milled, etched, or HF-dipped silicon surfaces examined in our Ti-ion getter-pumped transmission electron microscope (TEM) after exposure to air. They appear as weakly-strained non-crystalline intrusions into silicon bulk, that show up best in the TEM under conditions of strong edge or bend contrast. If ambient air exposure is <10 minutes, defect nucleation and growth can be monitored {\\em in situ}. Possible mechanisms of formation are discussed.

2002-01-01

203

Technical papers presented at the 4. symposium of specialists in electric operational and expansion planning. v. 2; Artigos tecnicos apresentados no 4. simposio de especialistas em planejamento da operacao e expansao eletrica. v. 2  

Energy Technology Data Exchange (ETDEWEB)

This symposium about electric operational and expansion planning presents several articles that approaches issues such as, monitoring the power system stability, electrical load modelling, reliability in power systems, optimization in power systems, integrated resources planning in power systems, reactive control through static compensators, power flow analysis, system modelling, etc

1994-12-31

204

Solenoid transport for heavy ion fusion  

Energy Technology Data Exchange (ETDEWEB)

Solenoid transport of high current, heavy ion beams is considered for several stages of a heavy ion fusion driver. In general this option is more efficient than magnetic quadrupole transport at sufficiently low kinetic energy and/or large e/m, and for this reason it has been employed in electron induction linacs. Ideally an ion beam would be transported in a state of Brillouin flow, i.e. cold in the transverse plane and spinning at one half the cyclotron frequency. The design of appropriate solenoids and the equilibrium and stability of transported ion beams are discussed. An outline of application to a fusion driver is also presented.

2004-06-15

205

Physics with Polarized Antiprotons  

Energy Technology Data Exchange (ETDEWEB)

Polarized antiprotons produced by spin filtering with an internal polarized gas target provide access to a wealth of single- and double-spin observables, thereby opening a window to physics uniquely accessible with the HESR at FAIR. This includes a first measurement of the transversity distribution of the valence quarks in the proton, and a first measurement of the moduli and the relative phase of the time-like electric and magnetic form factors G{sub E,M} of the proton. In polarized and unpolarized pp-bar elastic scattering open questions like the contribution from the odd charge-symmetry Landshoff-mechanism at large |t| and spin-effects in the extraction of the forward scattering amplitude at low |t| can be addressed.

2006-04-15

206

Niobium behaviour in liquid aluminium; Comportamento do niobio em aluminio liquido  

Energy Technology Data Exchange (ETDEWEB)

In this paper we studied the behavior of commercially pure niobium immersed in molten aluminum. The experiments were carried out 800 and 900 deg C during 2 to 128 hours. Chemical and metallographic analyses, as well as microhardness measurements of the niobium specimens were accomplished. An increase of niobium content in the aluminum bath with time was observed. Metallographic observations revealed the formation of Nb Al{sub 3} external intermetallic compound. During dissolution, fragments of this compound settled at the bottom of the crucible. This behaviour was also observed at 900 deg C, nevertheless with higher intensity. (author) 10 refs., 5 figs., 3 tabs.

1996-12-31

207

Material-not-categorized-as-waste survey for 1992  

Energy Technology Data Exchange (ETDEWEB)

In October 1992, the US Department of Energy, Richland Field Office (RL) requested that Westinghouse Hanford Company (WHC) respond to a letter from EM-331 asking for completion of a survey of items in storage but not categorized as waste (Roberts 1992). The letter contained an attachment with instructions on how to fill out the attached form and what to exclude from the survey (Appendix A). This report is a summary of the information from the response issued to RL. This report primarily is for use in estimating future waste volumes that may have been overlooked because of the nature of their classification as material not categorized as waste (MNCAW) (i.e., not yet declared Waste).

1993-07-01

208

Induced plasmon mutations affecting the growth habit of peanuts, A. hypogaea L  

International Nuclear Information System (INIS)

The effectiveness of the acridines ethidium bromide (EB) and acriflavine in inducing plasmon mutations was compared with the alkylating agents ethyl methanesulphonate (EMS) and diethyl sulphate and to #gamma#-rays. The growth habit (trailing versus bunch) of peanuts (A. hypogaea), controlled by genic-cytoplasmic interactions, was utilized. Breeding tests distinguishing nuclear from plasmon mutations were developed and are described in detail. Plasmon mutations were induced, but there were differences in mutation yields between the cultivars and the mutagens. (Auth.).

1978-01-01

209

Indirect stabilization of weakly coupled systems with hybrid boundary conditions  

CERN Document Server

We investigate stability properties of indirectly damped systems of evolution equations in Hilbert spaces, under new compatibility assumptions. We prove polynomial decay for the energy of solutions and optimize our results by interpolation techniques, obtaining a full range of power-like decay rates. In particular, we give explicit estimates with respect to the initial data. We discuss several applications to hyperbolic systems with {\\em hybrid} boundary conditions, including the coupling of two wave equations subject to Dirichlet and Robin type boundary conditions, respectively.

2011-01-01

210

Excitation of Plasma Fluctuations near ion Giro frequencies during RF Plasma Heating in URAGAN-3M Torsatron  

International Nuclear Information System (INIS)

Currentless plasma in Uragan-3M (U-3M) is produced and heated by absorption of RF power in the region of Alfven waves (AW). The process of plasma heating was explained in (2) as a result of Cherenkov absorption of energy of the fast (EM) and slow (kinetic Alfven) waves by electrons and turbulent ion heating due to excitation of short wave ion Bernstein waves (IBW). In this report we present results of studies of plasma density fluctuations showing existence of a narrow bands near the frequencies of ? ? n?ci (n=1,2,3).

2006-01-01

211

Equipment stainless steel entire versus steels bimetallics clad or overlay; Utilizacao de equipamentos de processo construidos em aco inoxidavel integral versus acos bimetalicos cladeado ou 'overlay'  

Energy Technology Data Exchange (ETDEWEB)

This study does not recommend the use of a pressure vessel made of integral stainless steel, due to the failure mechanisms under stress corrosion assisted by chlorides or polythionic acid. Are presented case studies of literature and analysis of reports of proceedings of RLAM reactors, showing that the materials produced by bimetallic clad overlay or are more appropriate, in terms of integrity, for use in equipment that the internal environment requires austenitic stainless steel specification.

2008-07-01

212

Electric induction on a trolley bus contact line, running parallel to a 138 KV overhead transmission line; Inducao em linha de contato de trolebus paralela a uma linha de transmissao de 138 kV  

Energy Technology Data Exchange (ETDEWEB)

Results obtained on induced current and voltage caused by a high voltage transmission lines running parallel at a trolley bus contact lines, are presented. A computer program in Basic language, was developed to calculate the electric induction, problems of safety, a theoretical development and mathematical model of the electric factors between two lines (inductor and induced) are also discussed. 11 figs., 1 tab., 8 refs.

1991-12-31

213

Determination of the semi-empiric relationship among the physical density, the concentration and rate between hydrogen and manganese atoms, and a manganese sulfate solution; Determinacao da relacao semi-empirica entre a densidade fisica, concentracao e razao entre atomos de hidrogenio e manganes em uma solucao de sulfato de manganes  

Energy Technology Data Exchange (ETDEWEB)

The bath of a manganese sulfate (BMS) is a system for absolute standardization of the neutron sources. This work establishes a functional relationship based on semi-empirical methods for the theoretical prediction of physical density values, concentration and rate between the hydrogen and manganese atoms presents in the solution of the BMS

2009-07-01

214

Virostatic potential of micro-nano filopodia-like ZnO structures against herpes simplex virus-1.  

Science.gov (United States)

Herpes simplex virus type-1 (HSV-1) entry into target cell is initiated by the ionic interactions between positively charged viral envelop glycoproteins and a negatively charged cell surface heparan sulfate (HS). This first step involves the induction of HS-rich filopodia-like structures on the cell surface that facilitate viral transport during cell entry. Targeting this initial first step in HSV-1 pathogenesis, we generated different zinc oxide (ZnO) micro-nano structures (MNSs) that were capped with multiple nanoscopic spikes mimicking cell induced filopodia. These MNSs were predicted to target the virus to compete for its binding to cellular HS through their partially negatively charged oxygen vacancies on their nanoscopic spikes, to affect viral entry and subsequent spread. Our results demonstrate that the partially negatively charged ZnO-MNSs efficiently trap the virions via a novel virostatic mechanism rendering them unable to enter into ...

2011-08-26

215

Study of ytterbium doping effects on structural, mechanical and opto-thermal properties of sprayed ZnO thin films using the Boubaker Polynomials Expansion Scheme (BPES)  

International Nuclear Information System (INIS)

In this work, ZnO thin films have been grown on glass substrates by using a solution of propanol (C3H8O), water (H2O) and zinc acetate (Zn(CH3CO2)2) in acidified medium (pH 5). The obtained films were n doped with ytterbium (Yb) at the rates of 100, 200 and 300 ppm. The structural features of the doped films were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. XRD analysis shows a strong (0 0 2) X-ray diffraction line for increasing Yb-doping amounts. This c-axis preferential orientation of ZnO crystallites is naturally required to use this oxide as transparent conductor in optoelectronic applications. Atomic force microscopy (AFM) analysis shows an enhancement in the surface roughness of the doped ZnO:Yb thin films. Optical measurements were performed in 300-1800 nm domain via transmittance T(?) and reflectance R(?) spectra. Conjoint optical and thermal ...

2009-10-19

216

Self-consistent full-potential linearized-augmented-plane-wave local-density electronic-structure studies of magnetism and superconductivity in C15 compounds: ZrZn_2 and ZrV_2  

International Nuclear Information System (INIS)

The electronic structure and properties of the cubic Laves phase (C15) compounds ZrZn_2 and ZrV_2 have been determined using our all-electron full-potential linearized-augmented-plane-wave (FLAPW) method for bulk solids. The computations were performed in two stages: (i) self-consistent warped muffin tin and (ii) self-consistent full potential. Spin-orbit coupling was included after either stage. The effects of the inclusion of the nonspherical terms inside the muffin tins on the eigenvalues is found to be small (of order 1 mRy). However, due to the fact that some of the bands near the Fermi level are flat, this effect leads to a much higher value of the density of states at E/sub F/ in ZnZr_2. The most important difference between the materials ZrZn_2 and ZrV_2 is the position of the d bands derived from the Zr and V atoms. Consequently, these materials have completely different Fermi surfaces. We have investigated the ...

217

Self-consistent full-potential linearized-augmented-plane-wave local-density electronic-structure studies of magnetism and superconductivity in C15 compounds: ZrZn/sub 2/ and ZrV/sub 2/  

Energy Technology Data Exchange (ETDEWEB)

The electronic structure and properties of the cubic Laves phase (C15) compounds ZrZn/sub 2/ and ZrV/sub 2/ have been determined using our all-electron full-potential linearized-augmented-plane-wave (FLAPW) method for bulk solids. The computations were performed in two stages: (i) self-consistent warped muffin tin and (ii) self-consistent full potential. Spin-orbit coupling was included after either stage. The effects of the inclusion of the nonspherical terms inside the muffin tins on the eigenvalues is found to be small (of order 1 mRy). However, due to the fact that some of the bands near the Fermi level are flat, this effect leads to a much higher value of the density of states at E/sub F/ in ZnZr/sub 2/. The most important difference between the materials ZrZn/sub 2/ and ZrV/sub 2/ is the position of the d bands derived from the Zr and V atoms. Consequently, these materials have completely different Fermi surfaces. We ...

1988-03-01

218

Interface engineering in chalcopyrite thin film solar devices  

Energy Technology Data Exchange (ETDEWEB)

Successful interface engineering requires compositional and electronic material characterization as a prerequisite for understanding and intentionally generating interfaces in photovoltaic devices. The paper gives an overview with several examples, all referring to Cu(In,Ga)(S,Se){sub 2} ('CIGSSe')-based solar cells, with an emphasis on characterization using highly specialized methods, such as elastic recoil detection analysis, X-ray emission spectroscopy and photoelectron spectroscopy using synchrotron and ultraviolet light for excitation, inverse photoemission spectroscopy and Kelvin probe force microscopy. First, the determination of the depth profile of the band gap energy E{sub g} in the absorber layer is demonstrated. The modification of E{sub g} towards both interfaces is discussed in terms of beneficial electronic effects. Next, the interface between absorber and buffer layers with alternative and promising non-toxic materials is considered. Between CIGSSe ...

2006-06-15

219

Influence of cobalt doping on the crystalline structure, optical and mechanical properties of ZnO thin films  

International Nuclear Information System (INIS)

Uniform and transparent thin films of Zn_1_-_xCo_xO (0 #=# 0.035, CoO (cubic) was detected as the secondary phase. Influence of Co addition on the volume fraction of grain boundaries has been interpreted. Increase in Co content in the range 0 #<=# x #<=# 0.10 led to quenching of near-band edge and blue emissions, decrease in band gap energy (E_g) from 3.36 eV to 3.26 eV, decrease in film thickness and refractive index and an increase in extinction coefficient of Zn_1_-_xCo_xO thin films. The change in nature of stress from compressive to tensile with lower to higher doping of Co is corroborative with the angular peak shift of (002) plane of ZnO lattice. An overall increase in microhardness of Zn_1_-_xCo_xO thin films up to x = 0.05 is attributed to change in microstructure and evolution of secondary phase and as the secondary phase separates out the overall stress is released leading to lowering ...

2010-07-01

220

Element distribution in the brain sections of rats measured by synchrotron radiation X-ray fluorescence  

International Nuclear Information System (INIS)

The concentration of trace elements in brain sections was measured by synchrotron radiation X-ray fluorescence. The relative concentration was calculated by means of the normalization of Compton scattering intensity approximately 22 keV, after the normalization for collecting time of X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate film for supporting sample. Furthermore, the statistical evaluation of the element distribution in various regions of the brain sections of the 20-day-old rats was tested. For investigating the distribution of elements in the brain of iodine deficient rats, Wistar rats were fed with iodine deficient diet and deionized water (ID group). The rats were fed the same iodine deficient diet, but drank KIO_3 solution as control (CT group). The results showed that the contents of calcium (Ca) in thalamus (TH) and copper (Cu) and iron (Fe) in cerebral cortex (CX) of ID rats were significantly lower than that of ...

2004-02-27

221

Elastic properties and structural studies on some zinc-borate glasses derived from ultrasonic, FT-IR and X-ray techniques  

Energy Technology Data Exchange (ETDEWEB)

Glasses in the system (1 - x) [29Na{sub 2}O- 4Al{sub 2}O{sub 3}- 67B{sub 2}O{sub 3}]- xZnO (0 {<=} x {<=} 35 mol%), have been prepared by the melt quenching technique. Elastic properties, X-ray and FT-IR spectroscopic studies have been employed to study the role of ZnO on the structure of the investigated glass system. Elastic properties and Debye temperature have been investigated using sound wave velocity measurements at 4 MHz at room temperature. The results showed that the density increases and the molar volume decreases while both sound velocities and the determined glass transition temperatures decrease with increase in x. X-ray and infrared spectra of the glasses reveal that the borate network consists of diborate units and is affected by the increase in the concentration of ZnO content. These results are interpreted in terms of the decrease in the N{sub 4} values (fraction of tetrahedral coordinated ...

2009-05-05

222

Trace Elements in Human Myocardial Infarction Determined by Neutron Activation Analysis  

International Nuclear Information System (INIS)

By means of neutron activation analysis, injured and adjacent uninjured human heart tissue from 12 autopsy cases with myocardial infarction are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent y-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, Zn and W. In the injured tissue compared to the uninjured, calculation on a wet weight basis showed a decrease in Co, Cs, K, Mo, P, Rb and Zn, and an increase in Br, Ca, Ce, La, Na, Sb and Sm. The differences in Ca, La, Mo, P and Zn are dependent on the age of the myocardial infarction, and the regression lines for these elements are given. The concentration of the trace elements in uninjured tissue from infarcted hearts is compared to the ...

1965-01-01

223

Study of metal concentration in sediment of some springs of Lebanon  

International Nuclear Information System (INIS)

Full text.Surficial sediment samples were collected from seventeen springs distributed all over Lebanon (east, west, north and south). Concentrations of metals Ca, Fe, Mn, Ni, Cu, Cr, Zn and Pb were determined by energy dispersive x-ray fluorescence technique. Irradiation was done by the radioisotope source Cd-109 and the detection by an EG and G Si(Li) detector. These analysis was done in attempt to assess the impact of anthropogenic sources on ground water quality. Metals concentration in sediment were found to be (Ca:0.05-47%, Fe:0.24-4.2%, Cr:Zn:Zn, Ni and Cr in other sites in comparison with other areas of the world were attributed to anthropogenic inputs. Lead concentrations obtained in this study were of the same order of magnitude as those obtained ...

1999-11-02

224

Strongly enhanced critical current density in MgB{sub 2}/Fe tapes by stearic acid and stearate doping  

Energy Technology Data Exchange (ETDEWEB)

Fe-sheathed MgB{sub 2} tapes with cheap stearic acid, Mg stearate and Zn stearate doping were prepared through the in situ powder-in-tube method. It is found that J{sub c}, H{sub irr} and H{sub c2} were significantly enhanced by doping. Compared to the pure tapes, J{sub c} for all the doped samples was improved by more than an order of magnitude in a high-field regime. At 4.2 K, the transport J{sub c} reached 2.02 x 10{sup 4} A cm{sup -2} at 10 T for the Zn stearate doped tapes and 3.72 x 10{sup 3} A cm{sup -2} at 14 T for the stearic acid doped samples, respectively. Moreover, at 20 K, H{sub irr} for the Zn stearate doped tape achieved 10 T, which is comparable to that of the commercial NbTi at 4.2 K. The improvement of J{sub c}-H properties in doped samples can be attributed to the increase of H{sub c2} resulting from the incorporation of C atoms into the MgB{sub 2} crystal lattice as well as a high density of ...

2007-05-15

225

Recent Progress in CdTe and CdZnTe Detectors  

CERN Document Server

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) have been regarded as promising semiconductor materials for hard X-ray and Gamma-ray detection. The high atomic number of the materials (Z_{Cd} =48, Z_{Te} =52) gives a high quantum efficiency in comparison with Si. The large band-gap energy (Eg ~ 1.5 eV) allows us to operate the detector at room temperature. However, a considerable amount of charge loss in these detectors produces a reduced energy resolution. This problem arises due to the low mobility and short lifetime of holes. Recently, significant improvements have been achieved to improve the spectral properties based on the advances in the production of crystals and in the design of electrodes. In this overview talk, we summarize (1) advantages and disadvantages of CdTe and CdZnTe semiconductor detectors and (2) technique for improving energy resolution and photopeak efficiencies. Applications of these imaging detectors in ...

2001-01-01

226

PIXE analysis of GaAs and ZnSe  

Energy Technology Data Exchange (ETDEWEB)

The optoelectronic compounds of GaAs and ZnSe are difficult to analyze by PIXE (particle-induced X-ray emission) due to the strong absorption of the As and Se K{sub {alpha}} X-rays. As part of a program to investigate optoelectronic materials using ion beam techniques, we have explored the possibility of using the high sensitivity of PIXE to check these materials for stoichiometry and dopant concentrations. The K{sub {alpha}} X-ray intensity ratios of Ga to As and Zn to Se have been investigated using H beams of 0.5 to 2.5 MeV and He beams of 1.0 to 2.5 MeV. The variation in the X-ray intensity ratio with beam energy and target thickness is modelled in terms of the cross section for X-ray production and the absorption coefficients of the X-rays in the target. The results of this model show the experimental conditions that must be satisfied in order that the X-ray intensity ratios are not strongly affected by X-ray absorption; and therefore, the ...

1990-01-01

227

PIXE analysis of GaAs and ZnSe  

International Nuclear Information System (INIS)

The optoelectronic compounds of GaAs and ZnSe are difficult to analyze by PIXE (particle-induced X-ray emission) due to the strong absorption of the As and Se K_#alpha# X-rays. As part of a program to investigate optoelectronic materials using ion beam techniques, we have explored the possibility of using the high sensitivity of PIXE to check these materials for stoichiometry and dopant concentrations. The K_#alpha# X-ray intensity ratios of Ga to As and Zn to Se have been investigated using H beams of 0.5 to 2.5 MeV and He beams of 1.0 to 2.5 MeV. The variation in the X-ray intensity ratio with beam energy and target thickness is modelled in terms of the cross section for X-ray production and the absorption coefficients of the X-rays in the target. The results of this model show the experimental conditions that must be satisfied in order that the X-ray intensity ratios are not strongly affected by X-ray absorption; and therefore, the ...

1989-06-01

228

Organic against inorganic electrodes grown onto polymer substrates for flexible organic electronics applications  

Energy Technology Data Exchange (ETDEWEB)

One of the most challenging topics in the area of organic electronic devices is the growth of transparent electrodes onto flexible polymeric substrates that will be characterized by enhanced conductivity in combination with high optical transparency. An essential aspect for these materials is their synthesis and/or microstructure which define the transparency, the stability and the interfacial chemistry which in turn determine the performance and stability of the organic electronic devices, such as organic light emitting diodes, organic photovoltaics, etc. In this work, we will discuss the latest advances in the growth of organic (e.g. PEDOT:PSS) and inorganic (e.g. zinc oxide-ZnO, indium tin oxide-ITO) conductive materials and their deposition onto flexible polymeric substrates. We will compare the optical, structural, nano-mechanical and nano-topographical properties of the inorganic and organic materials and we investigate the effect of their structure on their ...

2009-12-15

229

Morphology and luminescence properties of ZnO layers produced by magnetron spattering  

International Nuclear Information System (INIS)

We show that the morphology and the luminescence properties of ZnO layers produced by magnetron sputtering can be controlled by technological parameters of sputtering, particularly by the ratio of argon to oxygen gases in the gas flow during the growth process. Smooth and flat layers were produced with a high Ar/O ratio, while porous layers with various morphologies were obtained with a low Ar/O ratio. The layers produced with O/Ar ration equal to 10 exhibit extremely high near-bandgap luminescence intensity even higher in comparison with bulk ZnO single crystals. The free carrier density estimated from the analysis of photoluminescence spectra is also very high in these samples suggesting that these technological conditions promote both optical and electrical activation of the doping Al impurity. The samples grown with high Ar/O ratios exhibit strong visible emission which is controlled by the technological conditions.

2011-07-07

230

Mass effect and Pu removal from rats with Ca- or Zn-DTPA  

International Nuclear Information System (INIS)

Eight percent of an intramuscular injection of 27.6 nCi of "2"3"7Pu(NO_3)_4 was retained by rats at the injection site, after 22 days. More than 30% is usually retained following injection of more massive quantities of "2"3"9Pu. Treatment with Ca- or Zn-DTPA showed the former to be more effective when treatments were initiated 1 hr after Pu administration. When treatments were begun 7 days after the Pu injection, 416 nmol Ca-DTPA/kg was more effective in removing Pu than 28.7 nmol/kg (human dose level) of Zn- or Ca-DTPA. Due to its high specific activity and ease of detection, "2"3"7Pu permits facile experimentation in small animals at Pu mass levels comparable to those encountered in most human exposures.

1977-05-01

231

Initial stage of localized corrosion in artificial pits formed with photon rupture on Zn-5 mass% Al alloy-coated steel  

International Nuclear Information System (INIS)

The photon rupture method, by which oxide film and metal are removed by focused pulsed Nd-YAG laser beam irradiation, was applied to form artificial micro-pits in Zn-5 mass% Al alloy-coated steel. The zinc alloy-coated layer was removed by pulsed laser irradiation treatment for about one second in a neutral buffer solution with NaCl. The rest potential transient with the laser treatment was measured. In the early stage of the laser treatment the rest potential of zinc alloy-coated steel changed to the negative direction immediately after every irradiation of a laser pulse and then returned to the previous value. However, after the steel substrate was exposed to the solution, the rest potential moved to the positive direction immediately after every irradiation of a laser pulse and then returned to the previous value. The amplitude and duration of the potential change after the laser irradiation increased with repetition of laser irradiation, related to the pit ...

2007-05-01

232

Glass-cordierite-mullite ceramics of low dielectric constant; Tworzywa szklano-kordierytowo-mulitowe o malej przenikalnosci elektrycznej  

Energy Technology Data Exchange (ETDEWEB)

Glass-ceramic materials containing 0-60% glass, 0-40% cordierite and 0-40% mullite were developed with dielectric constant lower than of Al{sub 2}O{sub 3} (5.2-6.7). The following glasses were used: SiO{sub 2}, CaO-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-SiO{sub 2}, CaO-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}, CaO-ZnO-B{sub 2}O{sub 3}, CaO-ZnO-Al{sub 2}O{sub 3}B{sub 2}O{sub 3}, BaO-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-SiO{sub 2} and BaO-ZnO-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-SiO{sub 2}. The influence of the content of the particular components on the value of dielectric constant of the ceramics was investigated. (author). 9 refs, 3 tabs.

1997-12-31

233

Excitation cross sections for the ns "2S#->#np "2P resonance transitions in Mg"+ (n=3) and Zn"+ (n=4) using electron-energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Electron-excitation cross sections are reported for the 3s "2S#->#3p "2P(h,k) resonance transition in Mg"+ at energies from threshold (4.43 eV) to approximately 9 times threshold (40.0 eV). The electron-energy-loss merged-beams technique used in these measurements is described in detail. In addition, the method of separating contributions of the elastically scattered (Coulomb) and the inelastically scattered electrons in the present Mg"+ case and previously reported Zn"+ results [Phys. Rev. Lett. 67, 30 (1991)] is described. Comparisons in the experimental energy range are made for Mg"+ with the two five-state close-coupling theoretical calculations carried out herein, and with other published close-coupling, distorted-wave, and semiempirical calculations. The present Mg"+ cross sections and Zn"+ cross sections from earlier measurements are tabulated.

234

Effect of Na/sub 3/Zn- and Na/sub 3/Ca DTPA on the behaviour and biological effect of /sup 239/Pu in rats  

Energy Technology Data Exchange (ETDEWEB)

The effect of a complexon therapy scheme including early (in 1 h) administration of Na/sub 3/Ca DTPA and subsequent administration of Na/sub 3/Zn DTPA or Na/sub 3/Ca DTPA at a dose of 25 ..mu..Cimol/kg/day by three 2-week courses (5 times a week) with 2-week interruptions was studied in experiments on 541 male rats after intraperitoneal administration of /sup 239/Pu citrate complex (95 kBq/kg). The treatment resulted in a 3-fold lessening of the content of /sup 239/Pu and absorbed doses in the skeleton, a significant prolongation of the mean survival time (MST) from 452 to 593 days (Na/sub 3/Zn DTPA) and 643 days (Na/sub 3/Ca DTPA), and in a decrease of the osteosarcoma incidence from 76.4 to 32.6-41.2%. The ratio of osteosarcomas per 1 Gy retained in rats (0.076-0.083 %) did not differ from that in untreated animals.

1985-02-01

235

Copper and brass aged at open circuit potential in slightly alkaline solutions  

Energy Technology Data Exchange (ETDEWEB)

Surface oxide films were grown on 99.99% copper and brass (copper-zinc alloy, Cu77Zn21Al2) in 0.1 mol L{sup -1} borax solution at open circuit potential and were characterized using various experimental techniques. The composition of the passive films formed in situ on the different materials was studied using differential reflectance spectroscopy. The thickness of the oxide layers on copper and brass was compared by chronopotentiometric curves and potentiodynamic reductions. The electrical properties of each oxide were analyzed by means of electrochemical impedance spectroscopy. Their influence on the oxygen reduction reaction was also investigated using voltammetry hydrodynamic tools such as the rotating disk electrode. The results show that the incorporation of Zn to Cu in brass changes the composition and the thickness of the surface film. The films grown on brass tend to be thicker but less resistive and Zn compounds ...

2009-12-01

236

Comparison of the effect of catalysts in coal liquefaction with tetralin and coal tar distillates  

Energy Technology Data Exchange (ETDEWEB)

Special CoMo/Al{sub 2}O{sub 3} catalysts were prepared for testing in coal liquefaction: a conventional CoMo/Al{sub 2}O{sub 3} catalyst, one containing Zn as a second promoter and one having the alumina acidified with fluorine. Their activities were compared with that of red mud. The experiments were conducted in a stirred autoclave with a subbituminous coal and solvent (tetralin, anthracene oil or creosote oil) at 425{degree}C and 17 MPa. The liquefaction products were fractionated into oils, asphaltenes and preasphaltenes with pentane, toluene and THF. The Co(Zn)Mo/Al{sub 2}O{sub 3} catalysts have far higher activities than red mud. Zn and fluorine have beneficial effects on the catalyst activity. Coal tar distillates give higher conversions and oil + gas yields than tetralin when the prepared catalysts are used. 17 refs., 7 tabs.

1997-10-01

237

Using n-ZnO-Al as window layer in pilot production of CIGSSe solar modules: Status and trends. Status of CIGSSe pilot scale production at Munich; Einsatz von n-ZnO:Al als Fensterschicht in der Pilotfertigung von CIGSSe-Solarmodulen: Status and Entwicklung. Status der CIGSSe-Pilotfertigung in Muenchen  

Energy Technology Data Exchange (ETDEWEB)

Shell Solar GmbH is working on a variant of the so-called stacked elemental layer process for CIGSSe absorber production. The metal films resp. the selenium are deposited on the Mb electrode at room temperature by DC sputtering (CIG) or evaporation (Se) and then processed into semiconductors by rapid thermal annealing (RTP). Currently, the mean efficiency of the pilot plant is i 12.6 {+-} 0.2 % for non-sealed 30 x 30 cm{sup 2} modules, the key efficiency is 13.0 %. In addition to the 30 x 30 cm{sup 2} pilot line, a small series of 60x90cm2 modules was constructed in December 2004. Here, the mean efficiency was 13.0 percent while the average module power was higher than 60 W. The contribution also describes investigations of ceramically sputtered n-ZnO:Al layers with reduced Al concedntrations of 1 percent and on reactively sputtered n-ZnO.Al layers from the double roller magnetron. (orig.) [German] Bei Shell Solar GmbH wird eine Variante des ...

2005-07-01

238

Vacancy complex scattering mobility of holes in IR-photoexcited p-type ZnTe  

Energy Technology Data Exchange (ETDEWEB)

Conductivity and Hall effect measurements were made in dark and IR-photoexcited p-type ZnTe samples between 77 and 300 K. Acceptor vacancy complexes of activation energies 0.09-0.1 eV were found to be present in the photoexcited samples. Different possible scattering mobilities were considered for both samples to explain the observed hole mobility. In the photoexcited sample a scattering mobility due to vacancy complexes was suggested for the first time to explain the results. The scattering centres were associated with native vacancy complexes segregated at the dislocations sites. The expression for the complex scattering mobility has been deduced using the curve fitting method to be {mu}{sub C}=(6.6x10{sup -11})T{sup 5} e{sup 725/T}. (orig.).

1990-10-01

239

Structure and properties of Li2Zn2(MoO4)3 crystals activated with copper and chromium ions  

British Library Electronic Table of Contents (United Kingdom)

Based on the corrected phase diagrams proper growth conditions for Li2Zn2(MoO4)3 crystals are selected. Large crystals (up to 100 mm), both impurity-free and activated by transition metal ions (Cu, Cr), are grown by the low-gradient Czochralski method. By the EPR method the charge state and structural position of copper and chromium ions are determined. The performed studies of luminescent properties show that for impurity-free crystals luminescence with ? = 388 nm with a two-exponential luminescence decay with ?1 = 2 ns and ?2 = 6 ns is observed at room temperature. At 77 K for both impurity-free crystals and those activated with transition metal ions luminescence with ? = 560 nm and the luminescence lifetime ? = 100 ns is observed, the intensity of luminescence with ? = 560 nm depending ...

2011-01-01

240

Spatial distribution of arsenic and heavy metals in willow roots from a contaminated floodplain soil measured by X-ray fluorescence spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

Under changing redox conditions some plants create plaques at their root surface, which may affect the mobility and uptake of As and heavy metals but it is unknown to what extent this also holds true for willows in contaminated floodplain soils. Therefore, willow roots were sampled from a phytoremediation trial in the contaminated floodplain of the river Elbe (Germany), cryofixed, freeze-dried, and cross sections were mapped for the distribution of As, Ca, Cu, Fe, K, Mn, Ni, S and Zn by synchrotron based X-ray fluorescence spectroscopy. The elements Ca, Cu, Ni, S and Zn were concentrated in the aerenchymatic tissue, and not associated with Fe and Mn. Mixed Fe-Mn plaques covered the surface of the willow roots and As was accumulated in these plaques. The observed association pattern between...

2011-01-01

241

SYNERGISTIC EFFECT OF N,N-BIS(PHOSPHONOMETHYL) GLYCINE AND ZINC IONS IN CORROSION CONTROL OF CARBON STEEL IN COOLING WATER SYSTEMS  

British Library Electronic Table of Contents (United Kingdom)

A protective film has been developed on the surface of carbon steel in low chloride aqueous environment using a synergistic mixture of an environmentally friendly phosphonic acid, N,N-bis(phosphonomethyl) glycine (BPMG), and zinc ions. Impedance studies of the metal/solution interface indicated that the surface film is highly protective against the corrosion of carbon steel in the chosen environment. Potentiodynamic polarization studies showed that the inhibitor is a mixed inhibitor. X-ray photoelectron spectroscopic analysis (XPS) of the film showed the presence of the elements iron, phosphorus, nitrogen, oxygen, carbon, and zinc. Deconvolution spectra of these elements in the surface film showed the presence of oxides/hydroxides of iron(III), Zn(OH)2, and [Zn(II)-BPMG] complex. This infe...

2011-01-01

242

Relationship between the lability of sediment-bound metals (Cd, Cu, Zn) and their bioaccumulation in benthic invertebrates  

British Library Electronic Table of Contents (United Kingdom)

The present study has investigated metal contamination at nine sites (10 sampling stations) from the English Channel to the Mediterranean Sea, including low level and highly contaminated sediments. Both total and labile concentrations of metals were determined in superficial sediments. The influence of different pHs was tested and metal lability at pHs encountered in the gut of invertebrates (the ragworm Nereis diversicolor, the blue mussel Mytilus edulis, the Japanese oyster Crassostrea gigas) was compared with the distribution of metals in various operationally defined geochemical fractions. Cd showed the highest lability and Cu the lowest, whereas Zn lability was intermediate. Metal concentrations were determined in bivalves at six sites and in worms at three sites. Cd in living organis...

2007-01-01

243

PERFORMANCE-LIMITING DEFECTS IN CDZNTE DETECTORS.  

Energy Technology Data Exchange (ETDEWEB)

We studied the effects of small, <20 {micro}m, Te inclusions on the energy resolution of CdZnTe gamma-ray detectors using a highly collimated X-ray beam and gamma-rays, and modeled them via a simplified geometrical approach. Previous reports demonstrated that Te inclusions of about a few microns in diameter degraded the charge-transport properties and uniformity of CdZnTe detectors. The goal of this work was to understand the extent to which randomly distributed Te-rich inclusions affect the energy resolution of CZT detectors, and to define new steps to overcome their deleterious effects. We used a phenomenological model, which depends on several adjustable parameters, to reproduce the experimentally measured effects of inclusions on energy resolution. We also were able to hound the materials-related problem and predict the enhancement in performance expected by reducing the size and number of Te inclusions within the crystals.

2006-10-29

244

Nomographs for the optimum solar pond driven LiBr/ZnBr sub 2 /CH sub 3 OH absorption-refrigeration system  

Energy Technology Data Exchange (ETDEWEB)

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

1992-07-01

245

Microanalytical method development for Fe, Cu and Zn determination in colorectal cancer cells  

British Library Electronic Table of Contents (United Kingdom)

Microanalytical methods suitable for the determination of Fe, Cu in HT-29 (human colon adenocarcinoma) cells treated with different iron compounds (Fe(II) sulfate, Fe(III) chloride, Fe(III) citrate and Fe(III) transferrin) and cultured in medium supplemented or not with 10% (v/v) fetal calf serum (FCS) by total reflection X-ray fluorescence spectrometry (TXRF) and simultaneous graphite furnace atomic absorption spectrometry (GF-AAS) were developed. The developed TXRF method was also suitable for Zn determination in the samples. The main advantage of the proposed methods is the execution of all sample preparation steps following incubation and prior to the elemental analysis in the same Eppendorf tubes. Sample preparation was performed at microscale (115mL sample volume) with 65% nitric aci...

2011-01-01

246

Leaching of zinc sulfide by Thiobacillus ferrooxidans: Bacterial oxidation of the sulfur product layer increases the rate of zinc sulfide dissolution at high concentrations of ferrous ions  

Energy Technology Data Exchange (ETDEWEB)

This paper reports the results of leaching experiments conducted with and without Thiobacillus ferroxidans at the same conditions in solution. The extent of leaching of ZnS with Bacteria is significantly higher than that without bacteria at high concentrations of ferrous ions. A porous layer of elemental sulfur is present on the surfaces of the chemically leached particles, which no sulfur is present on the surfaces of the bacterially leached particles. The analysis of the data using the shrinking-core model shows that the chemical leaching of ZnS is limited by the diffusion of ferrous ions through the sulfur product layer at high concentrations of ferrous ions. The analysis of the data shows that diffusion through the product layer does not limit the rate of dissolution when bacteria are present. This suggests that the action of T.ferroxidans in oxidizing the sulfur formed on the particle surface is to remove the barrier to diffusion by ...

1999-12-01

247

In situ ligand exchange of thiol-capped CuInS2/ZnS quantum dots at growth stage without affecting luminescent characteristics  

British Library Electronic Table of Contents (United Kingdom)

An aliphatic thiol ligand of CuInS2/ZnS core/shell quantum dots is replaced with a hydroxyl-terminated thiol ligand by utilizing `on-off state' of ligands during growth stage of the quantum dots. After the ligand-exchange, negligible differences were observed on both photoluminescence spectrum and luminescent quantum efficiency. The reason for the high retention of luminescent efficiency comes from no local agglomeration and no surface deterioration of QDs. It is also observed that 70% of initial ligands are exchanged by the replacing ligand, determined by FT-IR and 1H NMR. The proposed method provides the quantum dots with an excellent dispersibility in polar solvents, supported by identical luminescence decay characteristics of the QDs.

2011-01-01

248

Improving the sheared edge in the blanking of commercial AZ31 sheet through texture modification  

British Library Electronic Table of Contents (United Kingdom)

Commercial rolled magnesium sheets of alloys AZ31 (Mg-3 mass%Al-1 mass%Zn) and ZE10 (Mg-1 mass% Zn-<1 mass% Rare Earths) in O-temper condition were used for blanking experiments near room temperature. A serrated fracture surface can be observed in case of AZ31 but not in case of ZE10. During the shearing process of the AZ31 sheet, many micro cracks parallel to the sheet plane are generated in the shearing zone. These micro cracks lead to the formation of loose particles during the shearing operation, which interfere with further processing of the part and incur additional costs by increasing the scrap rate. It is found that the strong basal texture of this alloy is an important reason for the generation of such serrated cracks. In this paper a new method of selective texture modification i...

2011-01-01

249

Gamma irradiation induced damage creation on the cation distribution, structural and magnetic properties in Ni-Zn ferrite  

International Nuclear Information System (INIS)

Ferrite of system, namely Ni_1_-_xZn_xFe_2O_4 with x = (0.0, 0.2, 0.4, 0.6, 0.8, 1.0), have been prepared by solid state reaction to investigate the effect of gamma rays irradiations using Co"6"0 source on the cation distribution, structural and magnetic properties. The unirradiated and irradiated samples were then subjected to characterization techniques such as X-ray diffraction, magnetization and AC susceptibility. The results of these characterizations are found to be different for irradiated from that of the pristine sample. The modifications in respect of irradiated samples are explained in terms of the ion-induced disorder. The important result of #gamma#-irradiation on the cation distribution, structural and magnetic properties is the change of ratio Fe"2"+/Fe"3"+. Possible reasons on the results are proposed.

2010-09-01

250

Estimation of essential and trace elements in some medicinal plants by PIXE and PIGE techniques  

Energy Technology Data Exchange (ETDEWEB)

Proton induced X-ray emission (PIXE) and proton induced {gamma}-ray emission (PIGE) techniques are employed for the determination of essential and trace elements in some commonly used medicinal plants of north east India. Light elements such as Na, Mg, Al and P are determined by PIGE while medium Z elements such as K, Ca, Mn, Fe, Cu, Zn, Rb and Sr are determined by PIXE. Analysis is performed on pellets (thick targets) prepared using powders of the specimens which, in turn, are obtained following a series of processing steps. Plant based biological certified reference materials (CRMs) served as standards for quantification. These elements are found to be present in varying concentrations in the studied plants, with the contents of Mn and Zn being notably large in certain specimens. Medicinal properties possessed by these plants have been correlated with their elemental distribution.

2008-04-15

251

Enhanced reflectance mirrors for space-borne HF laser applications  

Science.gov (United States)

Combined electron, photon, and intense UV irradiation tests have been carried out on three mirror designs, (Si, Al/sub 2/O/sub 3/)/sub 2/Ag, (Si, SiOx)nAg, and (ZnS, Al/sub 2/O/sub 3/)4Ag, to investigate their suitability for space-borne chemical laser applications. It is found that the (Si, oxide)nAg enhanced-reflectance design is a viable candidate for such applications, whereas ZnS, in combination with either ThF/sub 4/ or Al/sub 2/O/sub 3/, shows unacceptably high absorption increases at the 2.8-micron HF laser wavelength with irradiation. It is pointed out, however, that further experiments are needed to fully understand the effect of irradiation on the (Si, oxide)nAg enhanced-reflectance mirrors.

1981-01-01

252

Electronic structures of luminescence centers in pure and defective scintillation crystals AWO4 (A = Pb, Cd, Zn)  

International Nuclear Information System (INIS)

The electronic structures of the set of molecular clusters of dielectric oxide crystals AWO4 (A = Pb, Cd, Zn), the sizes of which increase sequentially are ab-initio calculated by the Restricted Hartree-Fock (RHF) method. The results of calculations of molecular orbitals and energy dependences of partial densities of electronic states of different clusters are compared each to other and to experimental data. It is found that calculated electronic structures of the tungstate groups and cations which are surrounded in cluster by certain number of the nearest neighbor atoms of the crystals quite well represent the experimentally obtained value of the forbidden gap of corresponding AWO4 crystal. (authors)

253

Electrically rechargeable zinc/air battery: a high specific energy system  

Energy Technology Data Exchange (ETDEWEB)

This contribution describes our research and development efforts towards the demonstration of a light-weight, low-cost 12 V/20 Ah electrically rechargeable Zn/air battery. We successfully developed electrodes having active areas of up to 200 cm{sup 2}. Deep discharge cycles at different currents as well as current-voltage curves are reported for a 10 cell Zn/air battery (serial connection) with a rated capacity of 20 Ah. Based on the discharge cycle at a power of 19 W, and the weight of the battery, a specific energy of more than 90 Wh/kg could be evaluated for the whole system. (author) 4 figs., 1 tab., 5 refs.

1999-08-01

254

Development of rechargeable monopolar and bipolar zinc/air batteries  

Energy Technology Data Exchange (ETDEWEB)

For the development of a rechargeable zinc/air battery, La[sub 0.6]Ca[sub 0.4]CoO[sub 3]-catalyzed (perovskite) bifunctional oxygen electrodes and pasted zinc electrodes were prepared and tested in monopolar zinc/air cells. In addition, a bipolar Zn/air stack was tested using reticulated copper foam as substrate for the zinc deposit. The cells were cycled in moderately alkaline ZnO-saturated electrolyte with KF as an electrolyte additive. The maximum power as well as the cycle life of the cells was investigated. The differences in porosity of the zinc electrode before and after the long-term test were analyzed using mercury porosimetry. (author) 8 figs., 13 refs.

1995-01-01

255

Determination of Proper Peaking Time for Ultra Lege detector at Medium Energies  

International Nuclear Information System (INIS)

Reducing count losses and pile-up pulse effects in quantitative and qualitative analysis is necessary for accuracy of analysis. Therefore, the optimum peaking time for particular detector systems is important. For this purpose, pure Se and Zn elements were excited by 59.5 keV ?-rays from a 50 mCi 241Am annular radioactive source in this study. The characteristic x-rays emitted from pure Se and Zn elements were detected by using an ultra low energy Ge (Ultra-LEGe) detector connecting Tennelec TC 244 spectroscopy amplifier at different peaking time modes. Overall pulse widths were determined by HM 203-7 oscilloscope connecting amplifier. The proper peaking time for ultra low energy germanium detector (Ultra-LEGe) is determined about 4 ?s.

2008-08-25

256

Biosorption of Zn(II) by Thiobacillus ferrooxidans  

Energy Technology Data Exchange (ETDEWEB)

There have been a number of studies considering the possibility of removing and recovering heavy metals from diluted solutions. These are due, principally, because of the commercial value of some metals as well as in the environmental impact caused by them. The traditional methods for removing have several disadvantages when metals are present in concentrations lower than 100 mg/l. Biosorption, which uses biological materials as adsorbents, has been considered as an alternative method. In this work, variables like pH and biomass chemical pretreatment have been studied for its effect on the capacity for zinc biosorption by Thiobacillus ferrooxidans. Also, studies to determinate the time for zinc adsorption were carried out. Results indicate that a capacity as high as 82.61 mg of Zn(II)/g of dry biomass can be obtained at a temperature of 25 C and that the biosorption process occurs in a time of 30 min. (orig.)

2000-06-01

257

Absolute electron scattering cross sections for the "2S#->#"2P transition in Zn"+ using energy-loss and merged-beams methods  

International Nuclear Information System (INIS)

Using the electron energy-loss method in a merged electron-ion beams geometry absolute, cascade-free excitation cross sections have been measured for the resonance "2S#->#"2P transition in Zn"+. Measurements were carried out at electron energies of below threshold (threshold at 6.011 eV) to 40 eV. Results are in very good agreement with close-coupling calculations and, away from threshold, lie below absolute line-emission cross sections which include effects of cascade into the "2P state from higher levels.

1991-02-20

258

A ZnO nanowire array film with stable highly water-repellent properties  

Energy Technology Data Exchange (ETDEWEB)

Highly water-repellent surfaces have been prepared from arrayed nanowires of zinc oxide (ZnO) by a treatment with stearic acid. The layers are electrochemically deposited on a nanocrystalline seed layer from an oxygenated aqueous zinc chloride solution. An advancing contact angle (CA) as high as 176{sup 0} is obtained with a very small hysteresis {approx}1{sup 0}. These results, supplemented by infrared spectroscopy, show that the stearic acid forms a very well-packed self-assembled monolayer. The CA measurements show a very good stability of the treated surface even when exposed to harsh conditions or long-term ambient illumination.

2007-09-12

259

Viscosity of the Earth's inner core: Constraints from nutation observations  

British Library Electronic Table of Contents (United Kingdom)

The gravitational torque applied on the Earth by the other celestial bodies generates periodic variations in the orientation of the Earth's rotation axis in space which are called nutations. Observations of Earth's nutations allow for insights into the physical properties of the inner core because of the presence of a normal mode, the Free Inner Core Nutation (FICN), which is characterized by a tilt of the inner core figure and rotation axes with respect to the mantle and outer core. The frequency of the FICN is controlled by the strength of the mechanical coupling acting at the inner core boundary (ICB) and by the ability of the inner core to deform under the action of centrifugal and gravitational forces. Attenuation of the FICN reflects energy dissipated by electromagnetic (EM) and visc...

2011-01-01

260

Unravelling the complexity of collective mental models: A method for developing and analysing scenarios in multi-organisational contexts  

British Library Electronic Table of Contents (United Kingdom)

In multi-organisational contexts, scenario building has been used to engage stakeholders in a critical discussion on issues of mutual importance, and to gain their support with regards to possible future responses. A review of existing literature suggests that much has been written regarding the process of scenario development and the benefits of the process, but the detailed analysis of scenario building outcomes, which encompass a large number of issues and their complex interconnections, has not been made explicit for studying and enhancing understanding of a complex societal problem. This paper presents a systematic method for analysing such complex outcomes in order to facilitate reflective thinking on important issues within the wider context for policy development. The method was em...

2011-01-01

261

The use of domestic microwave oven in experimental classes of organic chemistry: salicylaldehyde nitration; O uso de aparelhos de micro-ondas domesticos em aulas experimentais de quimica organica: nitracao de salicilaldeido  

Energy Technology Data Exchange (ETDEWEB)

The use of microwave in chemistry has known benefits over conventional heating methods, e.g. reduced reaction times, chemical yield improvement and the possibility if reducing or eliminating the use of organic solvents. We describe herein a procedure for the nitration of salicylaldehyde in water using a domestic microwave oven, which can be used as an experiment in the undergraduate chemistry laboratory. The experiment involves safe and rapid preparation and identification of the position isomers by thin layer chromatography and {sup 1}H NMR, or by their melting points. (author)

2010-07-01

262

Surge pressure behavior in reduced diameter segments of shipping terminals; Comportamento de pulsos de pressao em trechos de diametro reduzido de dutos de terminais maritimos  

Energy Technology Data Exchange (ETDEWEB)

In a shipping terminal, the pipeline in the pier usually has a diameter smaller than the main pipeline diameter. This diameter reduction amplifies the effects caused by hydraulic transients. It was noticed during simulations that check valves placed in the pier may introduce some error in the maximum pressure when it was modeled in a conventional fashion. The dynamic check valve model had been added to a commercial pipeline simulation software and the results was compared with a similar model using the method of characteristics. Considering a real state shipping terminal case, it was proved even a pipeline that works with low pressure and smooth elevation profile needs a detailed valve modeling to prevent the calculation of unreal pressure values in the region with diameter reduction. (author)

2004-07-01

263

Some preliminary views of plasma interaction: electromagnetic-launch systems  

Energy Technology Data Exchange (ETDEWEB)

This discussion outlines a few areas of fundamental research which appear vital for progress in developing advanced propulsion concepts using dc railgun thrusters. We have placed emphasis on the following: (1) dense plasma and high current density influences on changes in microstructure and properties of conventional rail conductors such as Cu, Al, and W alloys or composites; (2) the influences described in (1) on more advanced high temperature, microstrain resistant, materials such as amorphous tungsten; (3) location, description and temporal evolution of current, magnetic field, and losses during intense plasma-current field interactions with conductors; and (4) composite materials and sequentially sectioned structures for more efficient EM dc launcher configuration.

1982-07-14

264

Simulation of the New York Power Pool for dispatcher training  

Science.gov (United States)

This paper describes the simulation of the operating environment of the New York Power Pool (NYPP) within the Dispatcher Training Simulator facility at the New York State Electric and Gas Corporation (NYSEG). The NYSEG control center uses real-time data received from the NYPP control center to control its internal generation. In addition, the NYSEG dispatchers work very closely with the NYPP dispatchers. The exact emulation of the Generation Control functions of the NYPP EMS, and the associated data exchange with the NYSEG ECS, contribute greatly to the high degree of realism achieved in the NYSEG DTS facility. The accuracy of the power system simulation in the DTS has been validated against actual power system disturbances recorded at NYSEG.

1994-11-01

265

Predictability, complexity and learning  

CERN Document Server

We define {\\em predictive information} $I_{\\rm pred} (T)$ as the mutual information between the past and the future of a time series. Three qualitatively different behaviors are found in the limit of large observation times $T$: $I_{\\rm pred} (T)$ can remain finite, grow logarithmically, or grow as a fractional power law. If the time series allows us to learn a model with a finite number of parameters, then $I_{\\rm pred} (T)$ grows logarithmically with a coefficient that counts the dimensionality of the model space. While logarithmic growth of related information theoretic quantities has been found in previous work on learning, power law growth has not been seen in this context. We find that it is associated, for example, with the learning of infinite parameter (or nonparametric) models such as continuous functions with smoothness constraints. There are connections between the predictive information and measures of complexity that have been defined both in ...

2000-01-01

266

Optimized sizing model for renewable energy systems in rural areas; Modelo de dimensionamento otimizado para sistemas energeticos renovaveis em ambiente rurais  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this research was to develop a methodology for sizing integrated renewable energy systems, useful for rural areas, using simulation and optimization tools developed in MATLAB 6.0. The sizing model produces a system with minimum cost and high reliability level, based on the concept of loss of power supply probability (LPSP) for consecutive hours. An optimization model is presented and three different sizing scenarios are calculated and compared, showing flexibility in the elaboration of different project conceptions. The obtained results show a complete sizing of the energy conversion devices and a long-term cost evaluation. (author)

2005-05-15

267

Natural gas utilization in blast furnace of non-integrated pig-iron plants; Utilizacao de gas natural em altos fornos de usinas siderurgicas nao-integradas  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the authors investigate the technical and economical aspects of the natural gas injection in non-integrated pig-iron plants using charcoal in the blast furnace. The effects of the natural gas injection concerning the blast furnace flame temperature, charcoal consumption, productively and permeability are analyzed. It was found that the injection is beneficial in many ways, such as in the improvement of the productivity and quality, if the flame temperature is kept within an appropriate range. In the financial-economic project`s evaluation, the cash flow for the natural gas injection was analysed considering two blast conditions: through the drying and oxygen enrichment of the air. A sensibility analysis is presented in which the internal rate of return of the investment varies according to the prices of charcoal and oxygen. 3 refs., 3 figs., 3 tabs

1990-12-31

268

Modelling and migration of seismic data in transversely isotropic media; Modelamento e migracao de dados sismicos em meios transversalmente isotropicos  

Energy Technology Data Exchange (ETDEWEB)

The forward modelling and the prestack reverse time migration of seismic P-SV wave field was carried out in 2-D models of isotropic and anisotropic media which allow separation of P-SV and SH motion. The P-SV wave field can be described by a system of hyperbolic, first order differential equations in terms of particle velocity and stress. The system of five equations and five unknowns, namely horizontal (U) and vertical (V) velocity components, and three components of stress (T{sub xx}, T-z{sub z} and T{sub xz}) was solved numerically using second order space and forth order time finite differences operators. In order to attenuate numerical dispersion, a staggered grid was used. (author). 48 refs., 5 figs

1993-12-31

269

Implantation of an electronic system for real time neutron graphic images acquisition at the IPEN/CNEN Argonaut reactor; Implantacao de um sistema eletronico para aquisicao de imagens neutrongraficas em tempo real no reator Argonauta do IEN/CNEN  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is the implantation and characterization of a neutron radiography system that uses an electronic device for attainment of images in real time, for its implementation in the nuclear research reactor Argonauta at IEN/CNEN (Nuclear Engineering Institute of the Brazilian Nuclear Energy Commission). The Electronic Imaging System in Real Time is composed by a scintillator screen for neutron, a video camera (CCD), a digital plate and a computer with specific computational programs for digital processing of the images. The System in installed real time is apt to carry through neutron radiography inspections of static and dynamic events of several types of samples. (author)

2004-04-15

270

Fusion of protoplasts with irradiated micro protoplasts as a tool for radiation hybrid panel in citrus;Fusao de protoplastos com microprotoplastos irradiados como ferramenta para painel hibrido de radiacao em citros  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work was to combine asymmetric somatic hybridization (donor-recipient fusion or gamma fusion) to microprotoplast-mediated chromosome transfer, as a tool to be used for chromosome mapping in Citrus. Swinglea glutinosa micro protoplasts were irradiated either with 50, 70, 100 or 200 gamma rays and fused to cv. Ruby Red grapefruit or Murcott tangor protoplasts. Cell colonies were successfully formed and AFLP analyses confirmed presence of S. glutinosa in both 'Murcott' tangor and 'Ruby Red' grapefruit genomes. (author)

2009-12-15

271

Free electron laser: general concepts and present state of practical importance  

International Nuclear Information System (INIS)

Since the advent of the first free electron laser (FEL) in 1976 up to now, a series of principles, configurations and operation modes of these FELs have been devised and partially implemented. The principles refer to transverse FEL, longitudinal FEL, combined FEL, and transverse optical klystron FEL. Configurations may be standard or many-stage and the undulators may be magnetostatic, electrostatic or electromagnetic. The operation regimes may be low-gain Compton type, high-gain Compton type, Raman type, with and without space charge. The operation modes may be the amplification of an external coherent EM radiation, a self-amplified spontaneous emission (SASE), or an oscillator. The paper presents in detail these concepts and the limit between classical approach and the quantum approach of FEL. (Author).

1994-09-21

272

Extended cognition and the space of social interaction  

British Library Electronic Table of Contents (United Kingdom)

The extended mind thesis (EM) asserts that some cognitive processes are (partially) composed of actions consisting of the manipulation and exploitation of environmental structures. Might some processes at the root of social cognition have a similarly extended structure? In this paper, I argue that social cognition is fundamentally an interactive form of space management-the negotiation and management of "we-space"-and that some of the expressive actions involved in the negotiation and management of we-space (gesture, touch, facial and whole-body expressions) drive basic processes of interpersonal understanding and thus do genuine social-cognitive work. Social interaction is a kind of extended social cognition, driven and at least partially constituted by environmental (non-neural) scaffold...

2011-01-01

273

Exergy transfer in a porous rectangular channel  

British Library Electronic Table of Contents (United Kingdom)

Present paper is performed to investigate the heat and exergy transfer characteristics of forced convection flow through a horizontal rectangular channel where open-cell metal foams of different pore densities such as 10, 20 and 30PPI (per pore inches) were situated. All of the bounding walls of the channel are subjected to various uniform heat fluxes. The pressure drop and heat transfer characteristics are presented by two important parametric values, Nusselt number (NuH) and friction factor (f), as functions of Reynolds number (ReH) and the wall heat flux (q). The Reynolds number (ReH) based on the channel height of the rectangular channel is varied from 600 to 33 000, while the Grashof number (GrDh) ranged from approximately 105-107 depending on q. Based on the experimental data, new em...

2010-01-01

274

Estimating Field Volatility of Soil Fumigants Using CHAIN_2D: Mitigation Methods and Comparison Against Chloropicrin and 1,3-Dichloropropene Field Observations  

British Library Electronic Table of Contents (United Kingdom)

Academic, government, and industrial field researchers have generated a significant database of field studies of the volatility of soil applied fumigants. However, limited work exists in validating physical models against field volatility data sets and fully exploring the volatility parametric response surface. Field studies quantifying atmospheric flux for soil fumigants 1,3-dichloropropene and chloropicrin are validated against the United States Department of Agriculture (USDA Salinity Laboratory) soil physics model CHAIN_2D that was modified specifically for agronomic uses of soil fumigants. Comparison between model predictions and field observations for six unique field trials in five different states indicate that CHAIN_2D effectively captures the magnitude and duration of fumigant em...

2010-01-01

275

Embodied energy and emergy evaluation of a typical biodiesel production chain in China  

British Library Electronic Table of Contents (United Kingdom)

Biodiesel from non-grain feedstock has been considered as one of the proper substitutes for fossil fuels associated with a series of activities emerging in China in order to meet the resource shortage and develop the energy crops. This paper presents an ecological accounting framework based on embodied energy, emergy, and CO2 emission for the whole production chain of biodiesel made from Jatropha curcas L. (JCL) oil. The energy and materials invested in and CO2 emission from the whole process, including cropping, transportation, extraction, and production, are accounted and calculated. Also, EmCO2, the ratio of real CO2 released to the emergy-based sustainability indicator per joule biodiesel, is proposed in this paper to present a new goal function for low-carbon system optimization. Fina...

2011-01-01

276

Electromagnetic forming - a potentially viable technique for accelerator technology  

International Nuclear Information System (INIS)

Modern day accelerator development encompasses a myriad technologies required for their diverse needs. Whereas RF, high voltage, vacuum, cryogenics etc., technologies meet their functional requirements, high finish lapping processes, ceramic-metal joining, oven brazing, spark erosion or wire cutting etc., are a must to meet their fabrication requirements. Electromagnetic (EM) forming technique falls in the latter category and is developed as a special technology. It is currently catering to the development as a nuclear reactor technology, but has the potential to meet accelerator requirements too. This paper highlights the general principle of its working, simple design guidelines, advantages, and suggests some specific areas where this could benefit accelerator technologies

2003-02-03

277

Dynamic modelling of check valves in shipping terminals; Modelagem dinamica de valvulas de retencao em terminais maritimos  

Energy Technology Data Exchange (ETDEWEB)

As usual a shipping terminal contains a header and its diameter is smaller than the main pipeline diameter. This diameter reduction amplifies the effects caused by hydraulic transients. It was noticed during simulations that check valves without dynamic modeling may introduce some error in the maximum pressure results without a dynamic model approach. The current paper uses commercial pipeline simulation software to model the dynamic behavior of the check valves. It was studied the header diameter influence and how the check valve model type may change the maximum pressure in the pipeline. It was proved that even a pipeline that works with low pressure and small elevation drop needs a detailed valve modeling to prevent the calculation of unreal pressure values in the region with diameter reduction. (author)

2005-07-01

278

Assessment of the supramolecular structures presents into biological samples by SAXS technique;Avaliacao das estrutras supramoleculares presentes em amostras biologicas atraves da tecnica de SAXS  

Energy Technology Data Exchange (ETDEWEB)

In this work was made an assessment of the supramolecular structures presents into human breast tissue normal and pathological samples, as well as into two types of animals samples (tendon chicken and pork fat) using the small angle x-ray scattering (SAXS) technique. The scattering profiles of the samples were determined at the momentum transfer range O.150nm{sup -1}<=5:q(=4pi.sin({theta}/2)/{lambda})<=8.500nm{sup -1}. In this range, it was possible identify structures corresponding to collagen fibrils (glandular tissue) and to triacylglycerides (adipose tissue) from the correlation between the information extracted from the human breast tissues scattering profiles and those extracted from animals samples. (author)

2009-07-01

279

Antireflection coatings with FeSi2 layer: Application to spectrally selective infrared emitter  

British Library Electronic Table of Contents (United Kingdom)

We have developed efficient spectrally selective infrared (IR) emitters that can be utilized for thermophotovoltaic (TPV) power generation by using stainless steel (SUS304) substrates coated with b- FeSi2 thin films. To develop spectrally selective emitters, we theoretically propose antireflection (AR) coatings consisting of a single layer of a dielectric material having a high refractive index (~5) and are appropriate for use with metals such as stainless steels in the IR region. This type of AR coating is fabricated by sputtering a b- FeSi2 thin film on a polished SUS304 substrate. The reflectance in the IR region is successfully reduced to less than 10%. In addition, the AR properties are stable even at 700 K in air. Therefore, metals with AR coatings of b- FeSi2 can be applied to IR em...

2011-01-01

280

A contribution to the study of the thermal behavior and of the electric performance of squirrel-cage induction motors; Uma contribuicao ao estudo do comportamento termico e do desempenho eletrico de motores de inducao com rotor em gaiola  

Energy Technology Data Exchange (ETDEWEB)

A thermal-electric mathematical model for a squirrel cage induction motors which permits to specify the best motor for specific drive, under thermal and electric aspects based, only on manufacturer technical bulletins and technical information is presented. Changes of rotor parameters due Skin Effect and changes of winding resistances (both stator and rotor) with the temperature are considered. The accuracy of this model is appraised using experimental results. The thermal behavior and electric performance for some motors are obtained for continuos and intermittent duties with sinusoidal and non-sinusoidal voltages. (author)

1992-03-01

281

lnc5563r.073 - Index of  

Science.gov (United States)

TP ;{0= u_2G cIUF: NW!wO bJ|C Rqb' yw eA coS}8A! V^a8 Yb.Dp #y@0^ ylem 1L0. ; %F# BB^8 n!Y! c&Zn` 6Z0C .fY. ...

282

lla3321l.271  

Science.gov (United States)

... dm}ci yQo^ Q_aaSig[^n uu{mac[jOKf@P\\_rbd_N`T Q]^Y_U[d^UjQe\\[Nc_^xMRV]df\\tH_ ojnpumkmtbcpepmhjpeh mvutleojwd|[inYd_`Zn_`oik }Uh]x_kcb`[Wh`RO_Y`[Zeq\\oX ...

283

Zinc tetraaminophthalocyanine-Fe3O4 nanoparticle composite for laccase immobilization  

UK PubMed Central (United Kingdom)

Zinc tetraaminophthalocyanine-Fe3O4 nanoparticle composites were prepared by organic-inorganic complex technology and characterized. It has been proved that the ZnTAPc dispersed...Full Text Available

2007-12-01

284

Verification of zinc injection applicability to Japanese BWRs  

Energy Technology Data Exchange (ETDEWEB)

The verification test program on zinc injection applicability to Japanese BWRs was started in 1997. Laboratory tests using high temperature water loops under BWR reactor water conditions are in progress. This paper is an interim report on results obtained so far. Co-58 and Zn-65 were simultaneously used in the Co radioactivity buildup test to evaluate zinc injection suppression effects towards cobalt deposition on pre-oxidized stainless steel. The following results were obtained. The Co deposition was suppressed effectively by Zn injection, even when there was a pre-oxide film. For the test piping that had the pre-oxide film formed under the NWC (normal water chemistry) condition, when soaked under the HWC (hydrogen water chemistry) condition a large amount of Co-58 was taken into a small part of the inner layer. The distribution ratio of Co-58 in the inner layer and outer layer of the oxide film was almost the same for both the pre-oxidized ...

2002-07-01

285

Study of ytterbium doping effects on structural, mechanical and opto-thermal properties of sprayed ZnO thin films using the Boubaker Polynomials Expansion Scheme (BPES)  

Energy Technology Data Exchange (ETDEWEB)

In this work, ZnO thin films have been grown on glass substrates by using a solution of propanol (C{sub 3}H{sub 8}O), water (H{sub 2}O) and zinc acetate (Z{sub n}(CH{sub 3}CO{sub 2}){sub 2}) in acidified medium (pH 5). The obtained films were n doped with ytterbium (Yb) at the rates of 100, 200 and 300 ppm. The structural features of the doped films were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. XRD analysis shows a strong (0 0 2) X-ray diffraction line for increasing Yb-doping amounts. This c-axis preferential orientation of ZnO crystallites is naturally required to use this oxide as transparent conductor in optoelectronic applications. Atomic force microscopy (AFM) analysis shows an enhancement in the surface roughness of the doped ZnO:Yb thin films. Optical measurements were performed in 300-1800 nm domain via transmittance T(lambda) and reflectance R(lambda) spectra. ...

2009-10-19

286

Some optimization measurements and parameters of a radionuclide X-ray fluorescence spectrometer  

International Nuclear Information System (INIS)

An irradiation head with sample holders is described and measurement geometry is reported. Measurements were made for optimizing the distance between the source and the sample and for optimizing the sample diameter. The optimal distance between the source and the sample does not depend on the collimator diameter. The sample diameter should not exceed 30 - 35 mm. Sensitivity and detection limits were determined for Zn, Pb and Br and calibration curves were plotted. (M.D.) 6 figs., 2 tabs., 4 refs.

1986-01-01

287

Some capabilities of neutron methods for investigating materials and components of devices used in hydrogen power engineering  

International Nuclear Information System (INIS)

Structural units of a hydrogen fuel cell whose characteristics are advisable to investigate by different neutron scattering methods are discussed. The results obtained with the use of Bragg diffraction and small-angle neutron scattering from fuel membranes, nanocarbon-platinum catalysts, and Zn_1_-_xCu_xO hydrogen storage systems are presented.

2007-05-01

288

Radionuclide X-ray fluorescence analysis of solid aerosol particles on Synpor 4 collection filters  

International Nuclear Information System (INIS)

The feasibility was studied of the application of radionuclide X-ray fluorescence analysis to the identification and determination of chemical elements in the air. A description of the method is presented, the main stages of the analysis are discussed (sample preparation and standards, selection of radioactive radiation sources, geometry of measurement and evaluation of results). The method is illustrated on the determination of elements Fe, Cu, Zn, Br, and Pb in air samples taken in the city of Prague. (author) 2 tabs., 2 figs., 14 refs.

1992-01-01

289

Radionuclide X-ray fluorescence analysis of drinking water using preconcentration of trace metals on chelating cellulose exchanger ostsorb-oxin  

International Nuclear Information System (INIS)

Determination of Cr, Fe, Cu, Zn and Pb in drinking water preconcentrated on a chelating ion exchanger of Czechoslovak production is described. The analytical system consisted of a radionuclide source "2"3"8Pu, a Si/Li semiconductor detector and a multichannel analyzer. Results are compared with trehshold limit values recommended for drinking water. (author) 9 refs.; 2 figs.

1992-04-01

290

Pd-Na/F double exploding foil photoionization experiment  

Science.gov (United States)

The achievement of inner-shell photoionization of Zn-like Pd by means of two exploding foils is described. This resulted in the soft X-ray transition 3d94s2-3d104p at 46 A. It is shown that the photoionization of inner shell electrons in highly stripped ions can lead to X-ray transitions which may be candidates for X-ray lasers under 50 A.

1990-03-01

291

Newer systems for bacterial resistances to toxic heavy metals.  

UK PubMed Central (United Kingdom)

Bacterial plasmids contain specific genes for resistances to toxic heavy metal ions including Ag+, AsO2-, AsO4(3-), Cd2+, Co2+, CrO4(2-), Cu2+, Hg2+, Ni2+, Pb2+, Sb3+, and Zn2+. Recent progress with...Full Text Available

1994-09-01

292

Measurement of the oil consumption of compressors  

International Nuclear Information System (INIS)

This paper describes a method for measuring oil consumption in compressors. The oil is labelled with Zn 65. The consumed radioactive oil is retained in an activated carbon filter and its activity is measured continuously with a plastic scintillator detector. Measuring the oil consumption at a given operating levels takes about 15 minutes. At an oil consumption rate of about 1 g/h the measurement errors are of the order of +- 5%. (orig.).

293

Irradiation damage in spinel ceramics MgAl_2O_4 and ZnAl_2O_4: application to the transmutation of the nuclear waste  

International Nuclear Information System (INIS)

The transmutation of minor actinides in-reactor is one solution currently being studied for the long time management of nuclear waste. In the heterogeneous concept the radionuclides are incorporating in an inert ceramic matrix. The support material must be insensitive to radiation damage. Fission product damage is the main radiation damage source during the transmutation process and therefore it is of the utmost importance to study their effects. We irradiated spinels MgAl_2O_4 (matrix of reference) and ZnAl_2O_4 by fast ions (by example: (86)Kr of approximately 400 MeV) simulating the fission products. Under these conditions, the damage is primarily due to the electronic energy losses (Se). One of the structural features of spinel AB_2O_4 is that the two cations (A(2+) and B(3+)) can exchange their site. This phenomenon is quantified by the inversion parameter. We highlight by XRD in grazing incidence that the structural changes observed in MgAl_2O_4 correspond to ...

294

Identification of Thlaspi caerulescens Genes That May Be Involved in Heavy Metal Hyperaccumulation and Tolerance. Characterization of a Novel Heavy Metal Transporting ATPase1  

UK PubMed Central (United Kingdom)

Thlaspi caerulescens is a heavy metal hyperaccumulator plant species that is able to accumulate extremely high levels of zinc (Zn) and cadmium (Cd) in its shoots (30,000 μg...Full Text Available

2004-11-01

295

Identification and determination of elements in Taraxacum officinale plant from different Bratislava localities  

Energy Technology Data Exchange (ETDEWEB)

Elements Ti, Mn, Fe, Ni, Cu, Zn, Pb, Br, Rb and Sr were determined by the method of radionuclide X-ray fluorescence analysis with semiconductor detection in samples of Taraxacum officinale from various localities of Bratislava. The dependence of their content on the source and the degree of the air pollution was found out.

1983-01-01

296

Identification and determination of elements in Taraxacum officinale plant from different Bratislava localities  

International Nuclear Information System (INIS)

Elements Ti, Mn, Fe, Ni, Cu, Zn, Pb, Br, Rb and Sr were determined by the method of radionuclide X-ray fluorescence analysis with semiconductor detection in samples of Taraxacum officinale from various localities of Bratislava. The dependence of their content on the source and the degree of the air pollution was found out. (author).

1983-01-01

297

Heavy metals and some other elements in medicinal plants. Determined by X-ray fluorescence analysis  

International Nuclear Information System (INIS)

Determination of Mn, Fe, Cu, Zn, Hg, Pb, Br, Se, Rb, Sr and Cd in the medicinal plants by radionuclide X-ray fluorescence analysis (using "2"3"8Pu, "2"4"1Am/Ag and "1"2"5I) is described. (author). 12 refs., 2 tabs.

1995-01-01

298

Heavy element contamination of surface waters in the region Banska Stiavnica (SR) measured by radionuclide X/ray fluorescence analysis  

International Nuclear Information System (INIS)

Heavy metals (Pb, Cd, Mn, Cu, Zn, Fe) were determined in surface waters in the surroundings of the depositories of the mining shrubs in the region of Banska Stiavnica (SR) by radionuclide X-ray fluorescence analysis. Allowed concentrations of the determined metals are exceeded numerously (multiplicity in some cases was 10"3-10"6). (author).

1997-01-01

299

Determination of heavy metals in industrial wastewaters and their influence on activated sludge biocenose  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence method with a Si/Li semiconductor detector and "2"3"8Pu exciting source was used in the determination of Cr, Fe, Ni, Cu, and Zn content in industrial wastewaters. Simultaneously, the effects of the wastewaters on activated sludge biocenose were evaluated. (author) 6 refs.; 1 fig.; 1 tab.

1994-03-01

300

Corrosion of materials. A tabular survey. Korrosionsverhalten von Werkstoffen. Eine tabellarische Uebersicht  

Energy Technology Data Exchange (ETDEWEB)

This compact book of tables attempts to give practicians a survey of the corrosion behaviour of common structural and coating materials. Corrosion resistances are presented for steels, alloys, plastics, elastomers, graphite, glasses, and stoneware in environments of NaOH, HNO{sub 3}, SO{sub 2}, ZnCl{sub 2}, NH{sub 3}, H{sub 2}O{sub 2}, ethyl chloride, sodium acetate, and many others. (MM).

1990-01-01

301

Contribution to the in vitro multielement X-ray fluorescence analysis of human soft tissues  

International Nuclear Information System (INIS)

Determination of Mn, Fe, Ni, Cu, Zn, and Pb in human soft tissues by radionuclide X-ray fluorescence analysis (using "2"3"8Pu and "1"0"9Cd sources) is described. The results of multielement XRS analysis of selected human tissues are tabulated. They are in good agreement with the literature data. It is concluded that X-ray fluorescence technique is a suitable method for trace element determination. (author).

1986-11-01

302

Condenser replacement at Unterweser nuclear power station  

International Nuclear Information System (INIS)

In spite of extensive cooling water studies premature damage due to corrosion occurred on the CuZn20Al condenser tubes. It was then decided to incorporate new titanium-tubed condensers during the annual overhauls of 1983 and 1985 and also take ameliorating measures up to the exchange of individual condensers. (orig.).

303

Acrosome reaction of sperm in the mud crab Scylla serrata as a sensitive toxicity test for metal exposures.  

Science.gov (United States)

In order to test the sensitivity of the sperm cell of the mud crab Scylla serrata to heavy metals, the toxic effects of Ag+, Cd2+, Cu2+, and Zn2+ on the acrosome reaction (AR) were studied by artificially inducing the AR of sperm exposed to heavy metals, counting the AR rates by light microscopy, and observing structural changes in sperm by transmission electron microscopy. The AR in S. serrata occurs at two stages. The first stage (ARI) is the eversion of the subacrosomal material. The second stage (ARII) is the ejection of the acrosomal filament. The results showed the EC50 values of the AR based on (ARI + ARII)% for Ag+, Cd2+, Cu2+, and Zn2+ were 10.02, 2.14, 13.69, and 2.21 microg/L, and the EC50 values based on ARII % of Ag+, Cd2+, Cu2+, and Zn2+ were 1.96, 0.20, 1.46, and 0.34 microg/L. The order of toxicity is Cd2+ > Zn2+ > Cu2+ > Ag+ based on the percentage of reacted sperm at the ...

2009-04-28

304

Surface modification, organometallic and polyaryl polymer coatings, and flame spray technologies for preventing corrosion of metals. Final report  

Energy Technology Data Exchange (ETDEWEB)

To improve adherent properties of electrogalvanized steel (EGS) to polymeric topcoats, the surfaces of EGS were modified by polyelectrolyte-modified zinc phosphating solution. The electrochemical reaction between phosphating solution and EGS led to the complete coverage with fully grown hopeite crystals after only 5 sec treatment, thereby improving adhesion to topcoating and providing protection of EGS against corrosion. To evaluate the ability of polyphenylene sulfide (PPS) polyaryl thermoplastic coatings to protect zinc phosphate (Zn{center_dot}Ph)treated steels from corrosion in a wet, harsh environment ( 1.0 wt % H{sub 2}SO{sub 4}, 3.0 wt % NaCl and 96.0 wt % water at temperatures from 25{degrees} to 200{degree}C), we exposed them in an autoclave to attempt heating-cooling cyclic fatigue tests (1 cycle = 12 hr at 200{degrees}C + 12 hr at 25{degrees}C) up to 90 times. The major chemical reaction at the interface between the PPS and Zn in the ...

1995-07-01

305

Research of the ecosystem in coastal Baltic waters. Trace analysis under prior consideration of selenium and molybdenum. Final report; Oekosystemforschung in Litoralgewaessern der Ostsee. Spurenanalytik unter besonderer Beruecksichtigung von Selen und Molybdaen. Schlussbericht  

Energy Technology Data Exchange (ETDEWEB)

To study the biogeochemical behaviour, mobility and transport of trace metals in seawater (Se, Mo, Cd, Pb, Hg, Cu, Co, Fe, Ni, Zn), in suspended particulate matter (Mo, Cd, Pb, Cu, Co, Fe, Ni, Zn, Al, Mn) and in sediments of the inner and outer coastal regions, samples were collected on 3 separate cruises during a one year period (Mai 1993 - April 1994) at 20 stations in the coastal area of Mecklenburg-Vorpommern. Standard hydrographic parameters, nutrients and dissolved oxygen were also measured. Priority was taken to establish the methods for the determination of molybdenum and selenium. To study the behaviour of these two elements in detail, longterm measurements were carried out weekly between January 1993 and June 1994 at the `Messsteg/Warnemuende`. Because of parallel measurements correlations to biological, chemical and hydrographic parameters have been tested. The total database is summarized in the Appendix. The results are presented ...

1995-04-01

306

Neutron activation analysis for determination of selected trace elements responsible for immunity in foodstuffs and water in egypt  

International Nuclear Information System (INIS)

Selenium (Se), zinc (Zn), magnesium (Mg), molybdenum (Mo) and vanadium (V) in 28 types of Egyptian common foodstuffs as well as drinking and irrigation water samples were determined using neutron activation analysis (NAA) and atomic absorption spectrometry (AAS). The samples were collected from 74 sites over 13 governorates as well as the Nile river, wells and tap water in the regions of the Nile Delta, Sinai, the east and west desert, and north and south Egypt. These trace elements were chosen according to international references, which show the close relationship of their deficiencies to immunity-related diseases. Calculation values of daily uptake per capita were made with the results of analysis. The results, as calculated per 100 g dry weight, showed that some Egyptian foods are rich in Se including such fish (0.94 #mu#g), sesame (0.88 #mu#g), beef meat (0.48 #mu#g), instant tea (0.42 #mu#g), mushroom (0.34 #mu#g) and eggs (0.3 #mu#g), whereas the vegetables ...

307

Global positioning automatic vehicle location system  

Energy Technology Data Exchange (ETDEWEB)

Los Alamos National Laboratory (LANL) is a unique facility covering over 43 square miles. The Emergency Management and Response Office (EM&R) is required to respond, provide Incident Command (IC), and coordination for all Laboratory emergencies. This requires IC`s and support staff to respond to the actual scene of the incident. Since the IC is under numerous constraints and stress, the office wanted the capability of locating the EM&R vehicles on an electronic map. An automated vehicle location (AVL) system was required for the additional safety of the emergency response personal. The requirements for the AVL system include total automatic tracking and low cost. After careful consideration, it was determined that the most efficient and cost effective system would be based on packet radio technology as the transmission media. The location is determined by the Department of Defense Global Positioning System (GPS). The system that was ...

1997-03-01

308

Energy use in swine unit in the finishing system with waste treatment; Uso de energia em unidade suinicola em sistema de terminacao com tratamento de residuos  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to assess the energy flux and energetic balance related to the swine production and the recycling of residues generated by the system for utilization as organic fertilizers. The experiment was carried out at Vale dos Ipes Farm, located in the city of Ouro Verde do Oeste, in the Western of Parana State. One finishing phase swine unity containing 600 animals was monitored from January to June 2005. The treatment system is composed by one steel digester with capacity for 50 m{sup 3}, one sedimentation tank, one algae tank and one bio fertilizer storage tank. The swine barn cleaning is performed by dry scratching on a daily basis. The generated residues flow by gravitation through ducts towards the digester. The duration of the hydraulic retention period was 12 days. In the calculation of energetic efficiency, the energetic component ration is the greatest energetic cost in production system of finishing phase swine, corresponding to 95% from the total direct ...

2006-07-01

309

Evolution of improved varieties of sesame through induced mutations  

International Nuclear Information System (INIS)

Sesame varieties/genotypes showed a good response to radiation with gamma rays and treatments with EMS. In M_1 both gamma rays and EMS influenced germination, seedling height, survival of plants and pollen fertility/sterility, producing deleterious effects on these characters. Compared to black seeded genotypes, white seeded ones are more susceptible to radiation. Both gamma rays and EMS produced various types of morphological variations in M_2 generation. These were dwarf plant mutants, mottled and fleshy leaved mutants (sterile), fasciated stem, flower colour, altered phyllotaxy, early, uniculm, capsule size variations, multiple capsule/leaf axil, seed coat colour variations, indehiscent and semi-indehiscent type mutants. Moreover, studies on quantitative characters including seed yield revealed the induction of mutants in both positive and negative directions for such traits which made a good scope of selection of ...

2001-01-01

310

Transatlantic Initiative for Nanotechnology and the Environment - A new robust insitu tool for measuring nanoparticles and assessing their effects  

Environmental Research Database

ObjectivesWe have developed a life cycle perspective inspired conceptual model (CM) that suggests the importance of terrestrial ecosystems as a major repository of ZnO, TiO2, and Ag (Tier 1) manufactured nanomaterials (MNMs) introduced via the land application of MNM-containing biosolids. We propose to investigate the transport, fate, behavior, bioavailability, and effects of MNMs in(to) agroecosystems under environmentally realistic scenarios organized around three key hypotheses: Hypothesis (H1) Surface [continued...]DescriptionWe have developed a life cycle perspective inspired conceptual model (CM) that suggests the importance of terrestrial ecosystems as a major repository of ZnO, TiO2, and Ag (Tier 1) manufactured nanomaterials (MNMs) introduced via the land application of MNM-containing biosolids. We propose to investigate the transport, fate, behavior, bioavailability, and effects of MNMs in(to) agroecosystems under environmentally ...

2013-01-30

311

The effects of sacrificial coatings on hydrogen embrittlement and re-embrittlement of ultra high strength steels  

Energy Technology Data Exchange (ETDEWEB)

This paper describes an investigation of electrodeposited Zn-14% Ni and aluminium-based SermeTel 1140/962 coatings as possible replacements for cadmium. Slow strain rate tests were performed to measure the extent of direct hydrogen embrittlement of a high strength steel substrate as a result of the coating process and of hydrogen re-embrittlement caused by coating corrosion. The level of re-embrittlement was shown to depend on both the electrochemical potential of the coating and its barrier properties. Zn-14% Ni coatings caused the most re-embrittlement as they had the most active potential and contained through-thickness defects which left the steel exposed to hydrogen uptake. The microstructure of the high strength steel was also shown to be an important factor affecting the extent of embrittlement. AerMet 100 steel was more resistant than 300M steel and this was attributed to the presence of reverted austenite surrounding the martensite ...

2008-04-15

312

Study of the electron paramagnetic resonance spectra of Zn(antipyrine)_2(NO_3)_2:VO"2"+  

International Nuclear Information System (INIS)

In this work, a full ligand-field energy matrix (10x10) diagonalization treatment for 3d"1 ions in tetragonal symmetry is developed on the basis of the two-s.o.-coupling-parameter model. Spin Hamiltonian parameters (g factors g_|_|, g_p_e_r_p_e_n_d_i_c_u_l_a_r and hyperfine structure constants A_|_|, A_p_e_r_p_e_n_d_i_c_u_l_a_r) of the tetragonal V"4"+ center in Zn(antipyrine)_2(NO_3)_2 are calculated from the complete energy matrix diagonalization method and the perturbation theory method. The calculated results from both methods are not only close to each other but also in good agreement with the experimental values. Furthermore, the compressed defect structure of V"4"+ center is discussed.

2010-08-01

313

Solar thermal production of zinc: Program strategy  

Energy Technology Data Exchange (ETDEWEB)

The solar thermal production of zinc is considered for the conversion of solar energy into storable and transportable chemical fuels. The ultimate objective is to develop a technically and economically viable technology that can produce solar zinc. The program strategy for achieving such a goal involves research on two paths: a direct path via the solar thermal splitting of ZnO in the absence of fossil fuels, and an indirect path via the solar carbothermal/CH{sub 4}-thermal reduction of Zn O, with fossil fuels (coke or natural gas) as chemical reducing agents. Both paths make use of concentrated solar energy for high-temperature process heat. The direct path brings us to the complete substitution of fossil fuels with solar fuels for a sustainable energy supply system. The indirect path creates a link between today`s fossil-fuel-based technology and tomorrow`s solar chemical technology and builds bridges between present and future energy ...

1999-08-01

314

Remediation of contaminated agricultural soils near a former Pb/Zn smelter in Austria: Batch, pot and field experiments  

International Nuclear Information System (INIS)

Metal contaminated crops from contaminated soils are possible hazards for the food chain. The aim of this study was to find practical and cost-effective measures to reduce metal uptake in crops grown on metal contaminated soils near a former metal smelter in Austria. Metal-inefficient cultivars of crop plants commonly grown in the area were investigated in combination with in-situ soil amendments. A laboratory batch experiment using 15 potential amendments was used to select 5 amendments to treat contaminated soil in a pot study using two Barley (Hordeum vulgare L.) cultivars that differed in their ability to accumulate cadmium. Results from this experiment identified 3 of these amendments for use in a field trial. In the pot experiment a reduction in ammonium nitrate extractable Cd (<41%) and Pb (<49%) compared to the controls was measured, with a concurrent reduction of uptake into barley grain (Cd < 62%, Pb < 68%). In the field extractable fractions of Cd, Pb, and ...

2006-11-01

315

Properties of ZnO thin films prepared by radio-frequency plasma beam assisted laser ablation  

International Nuclear Information System (INIS)

Zinc oxide thin films were obtained by laser ablation of a Zn target in oxygen reactive atmosphere, the oxygen being supplied either by a standard gas inlet valve or from a radio-frequency (rf) oxygen plasma. Pt-coated silicon and MgO were used as substrates. The influence of the deposition parameters as laser wavelength (266, 355, 1064 nm), laser fluence (1.5-20 J/cm2) and oxygen pressure (1-60 Pa) was studied. The influence of the rf plasma beam addition on the morphological proprieties of zinc oxide films was particularly investigated, simultaneously with several configurations of the direction of the ablation plasma, the rf plasma beam and the substrate. The obtained films, with thicknesses in the range of 50 nm to 1 ?m have been characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), transmission electron microscopy (TEM).

2005-07-15

316

Phytostabilization of a metal contaminated sandy soil. II: Influence of compost and/or inorganic metal immobilizing soil amendments on metal leaching  

International Nuclear Information System (INIS)

A lysimeter approach (under natural climatologic conditions) was used to evaluate the effect of four metal immobilizing soil treatments [compost (C), compost + cyclonic ashes (C + CA), compost + cyclonic ashes + steel shots (C + CA + SS)) and cyclonic ashes + steel shots (CA + SS)] on metal leaching through an industrially contaminated soil. All treatments decreased Zn and Cd leaching. Strongest reductions occurred after CA + SS and C + CA + SS treatments (Zn: -99.0% and -99.2% respectively; Cd: -97.2% and -98.3% respectively). Copper and Pb leaching increased after C (17 and >30 times for Cu and Pb respectively) and C + CA treatment (4.4 and >3.7 times for Cu and Pb respectively). C + CA + SS or CA + SS addition did not increase Cu leaching; the effect on Pb leaching was not completely clear. Our results demonstrate that attention should be paid to Cu and Pb leaching when organic matter additions are considered for phytostabilization of ...

2006-11-01

317

Optimization of isotope production by cross section determination  

International Nuclear Information System (INIS)

In order to optimize the production of "2"0"1Tl and "6"7Ga using the (p, xn) reactions on enriched "2"0"3Tl and "6"8Zn targets we established a new set of cross section curves for the most relevant reactions. Target stacks made of up to 15 thin (50 #mu#m) natural Tl or Zn foils interleaved with brass degradation foils were irradiated with incident proton energies from 42 to 10 MeV in overlapping experiments. Yields for "2"0"0","2"0"1","2"0"2"m","2"0"3","2"0"4"mPB and "6"6","6"7","6"8Ga were computed from measured #gamma# emission rates. Where possible, cross section curves for the nuclear reactions involved were computed. Thick target yields and contamination ratios for enriched targets were derived and show good agreement with results from actual production runs. (orig.).

318

Neutron radiography with the cyclotron, 4  

International Nuclear Information System (INIS)

A real-time neutron radiography system was installed at the neutron radiography facility of Sumitomo Heavy Industries where a sub-compact cyclotron is used as a neutron generator and nominal neutron flux was observed as 1.1 x 10"6 n/cm"2/sec. Preliminary tests were made for various kinds of such components as collimators, scintillators, cameras and lenses and the system was chosen to give the highest quality images. Especially for the scintillator screen, screening tests were carried out for compounds of LiF/ZnS(Ag) and Gd_2O_3/ZnS(Ag) by radiographic film method. The neutron radiography image was converted to fluorescent images by means of the converter and observed by a SIT type TV camera. The video signal was directly displayed on a CRT or after processed with digital image processing devices. The characteristics of this system as for the resultant resolution are presented together with some actual application to dynamical fluid motion of ...

1986-01-01

319

Measuring instrument for radiometric monitoring of solids and heavy metals in water  

International Nuclear Information System (INIS)

A combination of measuring instruments, consisting of a Beta-Sedimeter and a radionuclide X-ray fluorescence instrument, is described. With the Beta-Sedimeter the C-14-radiation is measured. Through direct irradiation with photons of a Pu238-source in an ancillary irradiation chamber and energy dispersing measurement of the K- and L-radiation resp. of the excited heavy metals with the aid of a Si(Li)-semiconductor detector and a 4-channel analyzer the heavy metal concentrations of the heavy metals Zn, Cr, Ni and Pb are determined. For the determination of cadmium the indirect excitation with Am-241 and Dy-targets is described. The system produces records and operates fully automatically in a step-by-step mode with a testing cycle of 45 minutes. In connection with the process monitoring of the wastewater from a zinc plating plant during a period of 8 months the concentration of the solid material and of the metals Cr and Zn, which were ...

1979-01-01

320

Intense luminescence from porous ZnSe layers  

International Nuclear Information System (INIS)

We report on the possibility to prepare ZnSe porous layers with different degrees of porosity by means of electrochemical methods. The prepared porous structures were characterized using scanning electron microscopy (SEM), photoluminescence (PL) and cathodoluminescence (CL) techniques. The PL of the as-grown material and porous layers measured at low temperatures (10 K) was found to be dominated by an emission band at 2.796 eV as well as a band at 2.700 eV with several phonon replicas. The analysis of the dependence of these bands upon the excitation power density and temperature suggests that free-to-bound and respectively donor-acceptor electron transitions are responsible for the emission bands involved. The comparison of SEM and CL images taken from the same porous regions demonstrated that cathodoluminescence intensity from layers with small characteristic sizes of the porous entities (around 50 nm) is weaker than that inherent in bulk material, while porous ...

321

Extraction of copper-, nickel-, zinc- and cadmium complexes with 4-(2-pyridilazo)-resorcin and 2-aminopyridine  

International Nuclear Information System (INIS)

Extraction of copper-, nickel-, zinc- and cadmium complexes with 4-(2 pyridilazo)-resorcin (PAR) is studied in the presence of 2-aminopyridine (Am). Maximum optical densities of the extracts are attained at pH=7.5-8.0; 6.0-7.0; 6.5-7.0 and 7.0-8.0, respectively. The ratio of components in the complexes extractable by chloroform was defined by the method of isomolar series and equilibrium shift. It is established that nickel and copper are extracted to the organic phase as the NiAm(PAR)_2 and CuAmPAR complexes, and, in the case of zinc and cadmium, complexes of different composition are extracted, for example Zn(Am)_2PAR and ZnAm(PAR)_2. The light absorption spectra are studied and molar extinction coefficients of complex extracts are determined at lambdasub(max). It is shown that the general low of light absorption is observed within a sufficiently wide range of concentrations for all the elements.

1984-01-01

322

Estimation of trace elements in some anti-diabetic medicinal plants using PIXE technique  

Energy Technology Data Exchange (ETDEWEB)

Trace elemental analysis was carried out in various parts of some anti-diabetic medicinal plants using PIXE technique. A 3 MeV proton beam was used to excite the samples. The elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb and Sr were identified and their concentrations were estimated. The results of the present study provide justification for the usage of these medicinal plants in the treatment of diabetes mellitus (DM) since they are found to contain appreciable amounts of the elements K, Ca, Cr, Mn, Cu, and Zn, which are responsible for potentiating insulin action. Our results show that the analyzed medicinal plants can be considered as potential sources for providing a reasonable amount of the required elements other than diet to the patients of DM. Moreover, these results can be used to set new standards for prescribing the dosage of the herbal drugs prepared from these plant materials.

2006-08-15

323

Elemental investigation of Syrian medicinal plants using PIXE analysis  

Energy Technology Data Exchange (ETDEWEB)

Particle induced X-ray emission (PIXE) technique has been employed to perform elemental analysis of K, Ca, Mn, Fe, Cu, Zn, Br and Sr for Syrian medicinal plants used traditionally to enhance the body immunity. Plant samples were prepared in a simple dried base. The results were verified by comparing with those obtained from both IAEA-359 and IAEA-V10 reference materials. Relative standard deviations are mostly within {+-}5-10% suggest good precision. A correlation between the elemental content in each medicinal plant with its traditional remedial usage has been proposed. Both K and Ca are found to be the major elements in the samples. Fe, Mn and Zn have been detected in good levels in most of these plants clarifying their possible contribution to keep the body immune system in good condition. The contribution of the elements in these plants to the dietary recommended intakes (DRI) has been evaluated. Advantages and limitations of PIXE ...

2010-09-15

324

Elemental composition in mud crab Scylla serrata from Mahanadi estuary, India: in situ irradiation analysis by external PIXE.  

Science.gov (United States)

During the present study concentration of nine elements (K, Ca, Mn, Fe, Cu, Zn, Se, Br and Pb) in different tissues of mud crab Scylla serrata from Mahanadi estuary, India were determined by the external PIXE set up at Institute of Physics, Bhubaneswar, India. The study demonstrates the effectiveness of the technique in analyzing both soft and hard tissue samples from marine organisms and opens the door for non-destructive, multi-elemental analysis of tissue samples with a very little sample preparation by direct irradiation. This technique can be well utilized for analyzing the tissue samples for environmental, toxicological and nutritional purposes. The study also demonstrates the elemental concentrations from tissue samples of any crustaceans from Mahanadi estuary for the first time. Sex based difference in the elemental concentration of the mud crabs were marked, which may be related to the growth rate and other biological activities. No significant difference ...

2008-11-01

325

Economic evaluation of the solar carbothermic reduction of ZnO by using a single sensitivity analysis and a Monte-Carlo risk analysis  

Energy Technology Data Exchange (ETDEWEB)

The technical feasibility of the solar carbothermal reduction of ZnO has been successfully demonstrated in a pilot plant. The economics of this process is addressed by means of a single sensitivity analysis and a Monte-Carlo risk analysis. A medium-term and a long-term scenario have been investigated, each for a 5 and a 30 MW{sub th} plant. For a discount rate of 15% the zinc production costs vary between 482 and 245 $/t for the medium-term scenario and between 312 and 146 $/t for the long-term scenario, respectively. These costs do not account for the zinc oxide input material. In addition, a risk analysis was conducted for the 30 MW{sub th} long-term scenario. For each input parameter, a probability distribution was estimated and the probability distribution of the zinc production cost was calculated by means of a Monte-Carlo method. The expected mean zinc production costs vary from 95 $/t for a discount rate of 0%-286 $/t for a discount rate of 40%. (author)

2007-07-15

326

Determination of trace elements in Syrian medicinal plants and their infusions by energy dispersive X-ray fluorescence and total reflection X-ray fluorescence spectrometry  

Energy Technology Data Exchange (ETDEWEB)

X-ray fluorescence (XRF) and total-reflection X-ray fluorescence (TXRF) techniques suited well for a multi-element determination of K, Ca, Mn, Fe, Cu, Zn, Rb, and Sr in some Syrian medicinal plant species. The accuracy and the precision of both techniques were verified by analyzing the Standard Reference Materials (SRM) peach-1547 and apple leaves-1515. A good agreement between the measured concentrations of the previously mentioned elements and the certified values were obtained with errors less than 10.7% for TXRF and 15.8% for XRF. The determination of Br was acceptable only by XRF with an error less than 24%. Furthermore, the XRF method showed a very good applicability for the determination of K, Ca, Mn, Fe, Cu, Zn, Rb, Sr, and Br in infusions of different Syrian medicinal plant species, namely anise (Anisum vulgare), licorice root (Glycyrrhiza glabra), and white wormwood (Artemisia herba-alba)

2009-07-15

327

Biosorption of heavy metals from wastewater by biosolids  

Energy Technology Data Exchange (ETDEWEB)

In a study where the removal of heavy metals from wastewater is the primary aim, the biosorption of heavy metals onto biosolids prepared as Pseudomonas aeruginosa immobilized onto granular activated carbon was investigated in batch and column systems. In the batch system, adsorption equilibriums of heavy metals were reached between 20 and 50 min, and the optimal dosage of biosolids was 0.3 g/L. The biosorption efficiencies were 84, 80, 79, 59 and 42 % for Cr(VI), Ni(II), Cu(II), Zn(II) and Cd(II) ions, respectively. The rate constants of biosorption and pore diffusion of heavy metals were 0.013-0.089 min{sup -1} and 0.026-0.690 min{sup -0.5}. In the column systems, the biosorption efficiencies for all heavy metals increased up to 81-100 %. The affinity of biosorption for various metal ions towards biosolids was decreased in the order: Cr = Ni > Cu > Zn > Cd. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

2006-08-15

328

Biosorption of cadmium(II), zinc(II) and lead(II) by Penicillium simplicissimum: Isotherms, kinetics and thermodynamics  

Energy Technology Data Exchange (ETDEWEB)

The isotherms, kinetics and thermodynamics of Cd(II), Zn(II) and Pb(II) biosorption by Penicillium simplicissimum were investigated in a batch system. The effects of pH, initial metal ions concentration, biomass dose, contact time, temperature and co-ions on the biosorption were studied. Adsorption data were well described by both the Redlich-Peterson and Langmuir model. Chemical ion-exchange was found to be an important process based on free energy value from Dubini-Radushkevich isotherm for all metal ions. The results of the kinetic studies of all metal ions at different temperature showed that the rate of adsorption followed the pseudo second-order kinetics well. The thermodynamics constants {delta}G{sup o}, {delta}H{sup o} and {delta}S{sup o} of the adsorption process showed that biosorption of Cd(II), Zn(II) and Pb(II) ions on Penicillium simplicissimum were endothermic and spontaneous.

2008-12-30

329

Bioaccumulation of trace metals in farmed fish from South China and potential risk assessment  

British Library Electronic Table of Contents (United Kingdom)

Concentrations of trace metals were determined in water, sediment, fish feed and two species of farmed fish, pompano and snapper, collected from Daya Bay and Hailing Bay of South China in July 2007 and January 2008. Total average concentrations of Cu, Pb, Zn, Cd, Cr, Hg and As were 1.6, 2.7, 27.3, 0.025, 0.62, 0.18 and 0.59?g/gdrywt in pompano and 1.5, 2.6, 23.6, 0.020, 0.55, 0.22 and 0.53?g/gdrywt in snapper. In general, the concentrations of all target metals except Hg were positively correlated with lipid contents whereas negative correlations were observed between the metal concentrations and fish body weights. Model calculation indicated that dietary uptake of Zn and Cd predominate their accumulation in snapper, accounting for 99.9% and 98.2% of the total inputs. Risk ...

2011-01-01

330

Application of radionuclide X-ray fluorescence analysis to the monitoring of the quality of air  

International Nuclear Information System (INIS)

An X-ray fluorometric train was set up for analyzing gravitational fallout, and tested on standard reference samples of fly ashes from conventional power plants. Analysis of thin layers proved inappropriate, and therefore pelletization of the samples, either alone or together with the X-ray MIX binder, was applied. Sample grinding in an agate mortar was found sufficient to suppress the particle size effect. The optimum pressure was 20 MPa. The optimum geometry was sought for "1"0"9Cd source, and limits of detection of 2.78-0.47 #mu#g were achieved for Cr-Zr elements. Tominaga's method was employed for matrix effect correction. Ti, Fe, Cu, Zn, As, Rb, Sr, Zr and Pb were determined in the SRM's; the relative errors ranged from units per cent (for Zn, Rb, Sr and Zr present in concentrations about 100 ppm and for Fe in concentrations of units per cent) up to 45% (for Ti present in a concentration of 0.67%). The method developed was applied to the ...

1990-10-01

331

Anti-corrosive properties of an electropolymerized polymer coating on a shape memory alloy surface  

Energy Technology Data Exchange (ETDEWEB)

Acrylonitrile electropolymerization (in an aprotic and anhydrous medium) has been used as a way to build thin, homogeneous and covering polyacrylonitrile layers grafted on the surface of usual metals and specially on copper-based shape memory alloy: Cu-Zn-Al. The results of the study first confirm the possibility of grafting thin and covering polyacrylonitrile layers on Cu-Zn-Al surface. The morphology of the films however is influenced by the geometry of the polycristalline structure of the alloy and its superficial defects. Samples obtained after grafting polyacrylonitrile films were submitted to corrosion tests based on Electrochemical Impedance Spectroscopy (EIS) measurements in a NaCl/H{sub 2}O medium. Results show that some post-treatments of the grafted films are necessary to improve their protective role, while preserving the strong interfacial bondings. Actually, thermal and mechanical cycling of the shape memory alloy covered by ...

1996-01-01

332

Allosteric Tuning of the Intra-Cavity Binding Properties of a Calix[6]arene through External Binding to a ZnII Center Coordinated to Amino Side Chains  

British Library Electronic Table of Contents (United Kingdom)

Molecular recognition by calix[6]arene-based receptors bearing three primary alkylamino side chain arms (1) is described. Complexation of ZnII ion provides the dinuclear m-hydroxo complex ${{\\bf 2}{{{\\rm OH}\\hfill \\atop {\\rm G}\\hfill}}}$, XRD characterization of which, together with solution studies, provided evidence of its hosting of neutral polar organic guests G. Treatment of this complex with a carboxylic acid or a sulfonamide (XH) results in the formation of mononuclear species ${{\\bf 3}{{{\\rm X}\\hfill \\atop {\\rm G}\\hfill}}}$, one of which (X = Cl) has been characterized by XRD. A dicationic complex ${{\\bf 3}{{{\\rm RNH}{_{2}}\\hfill \\atop {\\rm G}\\hfill}}}$ is obtained upon treatment of ${{\\bf 2}{{{\\rm OH}\\hfill \\atop {\\rm G}\\hfill}}}$ with a mixture of an alkylamine and a strong acid....

2007-01-01

333

A process model of natural attenuation in drainage from a historic mining district  

Energy Technology Data Exchange (ETDEWEB)

A process model was used to better understand the controls on the chemical evolution of drainage in a historic mining district. At the Pecos Mine Operable Unit, New Mexico, drainage near the waste rock pile is acidic (pH varies from 3.0--5.0) and carries high concentrations of Zn, Al, Cu and Pb. As drainage flows toward the Pecos River, pH increases to greater than 7 and heavy metal content decreases. A process model of natural attenuation in this drainage shows the main controls on pH are reaction with a local bedrock that contains limestone, and concurrent mixing with tributary streams. Models that account for both calcite dissolution and mixing reproduce the observed decrease in aqueous metal concentrations with increasing pH. Contaminant concentrations attenuate primarily via two distinct pathways: Al, Cu, Fe and Pb precipitate directly from solution, whereas Zn, Mg, Mn and SO{sub 4} concentrations decrease primarily through dilution. ...

2000-06-05

334

A 1500-year record of lead, copper, arsenic, cadmium, zinc level in Antarctic seal hairs and sediments  

Energy Technology Data Exchange (ETDEWEB)

To reconstruct the profiles of heavy metal levels in the South Ocean ecosystem of Antarctica, the concentrations of lead (Pb), copper (Cu), arsenic (As), cadmium (Cd), and zinc (Zn) in seal hairs and lake sediments spanning the past 1500 years from Fildes Peninsula of King George Island and in weathering lake sediments from Nelson Island of West Antarctica were determined. The lead contents in the seal hairs and the weathering sediments show a sharp increase since the late 1800s, very likely due to anthropogenic contamination from modern industries. After the 1980s, the Pb content in seal hairs dropped by one-third, apparently due to the reduced usage of leaded gasoline in the Southern Hemisphere. Copper arises mainly from the weathering process, and its level may be substantially affected by climatic conditions. The concentrations of Cd, As, and Zn do not show any clear temporal trends.

2006-12-01

335

Thermal treatment of dusts from non ferrous metallurgical industries  

Energy Technology Data Exchange (ETDEWEB)

Three samples of dusts generated by the non ferrous metallurgical industries are treated between 200 and 800 degree centigree in controlled oxidizing and reducing atmospheres. The objective of this study is to recover the valuable metals from these wastes. The treatments of these solids under oxidizing conditions at 700 degree centigree are well adapted for two samples. The totality of valuable elements are concentrated in the treatments residues. The use of hydrogen at 600 degree centigree, permits the removal of up to 100 % of valuable metals contained in the treated industrial wastes. The recovery rate of valuable metals (Pb, Zn, Cu) as well as the Global Decontamination Factor are reported. (Author) 9 refs.

2000-07-01

336

The use of x-ray fluorescence in the detection of inorganic elements in medicines drugs  

International Nuclear Information System (INIS)

Based on the instrumental wavelength dispersive X-ray fluorescence technique of analysis (W D-X R F), the inorganic elements in four samples of commercial medicines drugs were analyzed. The samples were used without any chemical separation of the elements or chemical pre-treatment. Eleven elements could be identified, namely Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu and Zn. However, Si, Ti and Mn have not been mentioned in the printed instructions for the use of the medicines drugs by the producers. (author)

337

Texture development of AZ31 magnesium alloy during ECAE processing  

Energy Technology Data Exchange (ETDEWEB)

Mg-3%Al-1%Zn (AZ31) alloy was subjected to ECAE processing at 523 and 573 K. Microstructure observation and texture analysis were carried out using optical microscope and SEM-EBSD technique in order to investigate the process of microstructural changes including texture development during ECAE processing. Grain refinement during ECAE processing is enhanced by dynamic continuous recrystallization. The texture of the ECAE-processed AZ31 alloy specimens change with ECAE processing temperature, and the textural changes relate to deformation mechanisms that change with ECAE processing temperature. (orig.)

2003-07-01

338

Synthesis and characterization of nickel(II), chromium(III), cobalt(II), copper(II), zinc(II), and cadmium(II) complexes with isatin- isonicotinoylhydrazone  

International Nuclear Information System (INIS)

A few metal complexes of isatin-isonicotinoylhydrazone with Ni(II), Cr(III), Co(II), Cu(II), Zn(II) and Cd(II) have been prepared and characterized on the basis of elemental analyses, infrared and electronic spectra as well as "1H NMR spectra, conductivity and magnetic measurements. In view of the results obtained, it has been found that two molecules of isatin-isonicotinoylhydrazone are chelated to the central metal ion as bis-uninegative ONO tridentate ligand forming non-electrolytic octahedral metal complexes. (author)

1997-03-01

339

Relationship between copper speciation and cyanobacterial distribution in harbors and other coastal environments. Final report, 1 July 1993--1 November 1998  

Energy Technology Data Exchange (ETDEWEB)

The long term goal is to determine the ecological importance of specific toxic metals (copper and zinc) in harbors, through an understanding of their chemistry and biological effects at the base of marine food chains. This work provides information on potential problems with Zn and Cu, which may help to foresee problems in the future. Anthropogenic inputs of both metals are increasing; they are derived from diverse sources and are a simple function of population growth in coastal regions.

1998-11-01

340

Regenerative zinc/air and zinc/ferricyanide batteries for stationary power applications  

Energy Technology Data Exchange (ETDEWEB)

The authors report a novel configuration for a zinc-particle, packed-bed anode in which an open structure of high hydraulic permeability is maintained indefinitely in a cell with closely spaced walls by the formation of particle bridges and associated gaps. The configuration minimizes electrolyte pumping costs, allows rapid refueling and partial recharge, and provides for 100% zinc consumption. This approach benefits zinc/air fuel batteries by allowing nearly continuous operation and fuel recycle without commercial infrastructure; it benefits Zn/[Fe(CN){sub 6}]{sup {minus}3} batteries by eliminating shape-change and polarization problems found with planar anodes.

1994-05-01

341

Quantum Impurities in the Two-Dimensional Spin One-Half Heisenberg Antiferromagnet  

CERN Document Server

The study of randomness in low-dimensional quantum antiferromagnets is at the forefront of research in the field of strongly correlated electron systems, yet there have been relatively few experimental model systems. Complementary neutron scattering and numerical experiments demonstrate that the spin-diluted Heisenberg antiferromagnet La2Cu(1-z)(Zn,Mg)zO4 is an excellent model material for square-lattice site percolation in the extreme quantum limit of spin one-half. Measurements of the ordered moment and spin correlations provide important quantitative information for tests of theories for this complex quantum-impurity problem.

2002-01-01

342

Photoacoustic response to X-ray absorption in copper and brass  

Energy Technology Data Exchange (ETDEWEB)

The X-ray photoacoustic spectra of copper and brass (64.7 wt.% Cu and 35.3 wt.% Zn) have been measured at XANES (X-ray absorption near-edge structure) regions using synchrotron radiation. These spectra were compared with optical density of X-ray spectra. It is shown that the information derived from XANES is also included in the X-ray photoacoustic spectrum which reflects the heat production processes in copper and brass. However, the results showed that the increases and changes of the photoacoustic signal were different from those of the X-ray absorption coefficient at XANES regions. (author).

1990-09-01

343

Optimized Zn-electrode for the rechargeable zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

For the development of a long-lived electrically rechargeable zinc/air battery, the structure and wettability of pasted zinc electrodes were optimized. Pasted zinc electrodes, having the same nominal capacities but containing 1% to 10% cellulose, were prepared and tested under defined charge and discharge conditions in zinc-oxygen cells. The maximum power as well as the cycle life of these cells were measured. After different times of operation, the porosity and the pore size distribution of the pasted zinc electrodes were measured by means of mercury porosimetry. (author) 4 figs., 1 tab., 6 refs.

1996-06-01

344

Neutron radiography with the cyclotron, 5  

International Nuclear Information System (INIS)

Reliable facility of cyclotron-based real time neutron radiography system has been developed and applied to some industrial components. The equipment for neutron fluoroscopy is based on a sub-compact cyclotron and a LiF/ZnS (Ag) fluorescent screen viewed by a silicon intensifier target TV camera. The real time image is monitored on a CRT, recorded with a standard video recorder and processed by a digital image processor. The effectiveness of our real time neutron radiograph has been demonstrated to be applicable to not only the dynamic observation but also the magnifying and stereoscopic observation of fluoroscopic images. (author).

1987-01-01

345

Multielement analysis of air samples  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis for nondestructive determination of Fe, Zn, Pb, and Br in air samples collected on nitrocellulose membrane filter Synpor 4 is described. A "2"3"8Pu source for the excitation and a semiconductor Si/Li detector for the detection of characteristic and L-fluorescent radiation of the above elements were used. A correction method based upon the measurements of simple or multiple Compton scattering for compensation of varying mass per unit area values in sample deposits was theoretically proposed and experimentally tested. The results obtained both with and without the correction were compared and good agreement with those given by atomic absorption spectrometry was observed. (author).

1981-01-01

346

LUCIFER, a potentially background-free approach to the search for neutrinoless double beta decay  

British Library Electronic Table of Contents (United Kingdom)

LUCIFER (Low-background Underground Cryogenic Installation For Elusive Rates) is a new project for the study of neutrinoless Double Beta Decay, based on the technology of scintillating bolometers. These devices promise a very efficient rejection of the alpha background, opening the way to a virtual background-free experiment if candidates with a transition energy higher than 2615 keV are investigated. The baseline candidate for LUCIFER is 82Se. This isotope will be embedded in ZnSe crystals grown with enriched selenium and operated as scintillating bolometers in a low-radioactivity underground dilution refrigerator. In this paper, the LUCIFER concept will be introduced. The sensitivity and the very promising prospects related to this project will be discussed.

2011-01-01

347

Influence of the reductive preparation conditions on the morphology and on the electrochemical performance of Sn/SnSb  

Energy Technology Data Exchange (ETDEWEB)

Lithium storage metals and alloys can be suitable high-capacity anode materials for lithium-ion batteries, when the morphology is specifically designed. Here, we compare three different Sn/SnSb multiphase anode materials in powder form, which have been prepared in aqueous and organic solution by chemical precipitation using NaBH{sub 4} or Zn as reductive agents. The obtained morphologies, chemical compositions, and the electrochemical performance will be comparatively discussed. The variety of synthesis parameters which have an effect on the morphology of the obtained anode materials will be particularly highlighted.

2004-03-15

348

Electron momentum density measurements by means of positron annihilation and Compton spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The electron momentum density is measured applying positron annihilation and Compton spectroscopy in order to get information about electron wave functions. Compton spectroscopic measurements of Pd-Ag and Cu-Zn alloy systems are carried out taking into account crystal structure, mixability, and order state. Three-dimensional momentum densities of silicon are determined in order to get better information about its electronic structure. The momentum density and the spin density of ferromagnetic nickel are investigated using angular correlation curves.

1982-01-01

349

Driving-cycle testing for the PSI zinc/air battery  

Energy Technology Data Exchange (ETDEWEB)

This contribution describes our research and development effort towards an electrically rechargeable zinc/air battery which is capable of meeting the demands of a scaled power profile (driving-cycle tests). The power profiles DST (Dynamic Stress Test) and ECE15-L (European Driving Cycle for alkaline Batteries) were applied to our 200 and 50 cm{sup 2} electrically rechargeable Zn/O{sub 2} cells with nominal capacities of 30 and 7.5 Ah, respectively. (authors)

2000-07-01

350

Determination of constituent elements in some Nigerian medicinal plants by thermal-neutron activation analysis  

Energy Technology Data Exchange (ETDEWEB)

This study of the inorganic chemical composition of 10 different Nigerian medicinal plant species, using the technique of instrumental neutron activation analysis (INAA), resulted in the determination of the concentrations of 18 major, minor, and trace elements: Al, Ba, Br, Ca, Cl, Eu, Fe, Ga, K, La, Mn, Na, Sb, Sc, Si, Sm, V, and Zn. The parts of the plants used were roots, leaves, and bark. The NBS SRM 1571 Orchard Leaves was also analyzed to assess the accuracy of the procedures used. 21 refs., 4 tables.

1984-04-02

351

Activation of aluminium metal to evolve hydrogen from water  

Energy Technology Data Exchange (ETDEWEB)

The method of aluminium metal activation by liquid eutectics Ga-In (70:30) and Ga-In-Sn-Zn (60:25:10:5) is developed. Subsequent dispersion of the obtained specimens up to a particle size of >0.5mm leads to the drastic interaction of aluminium powder and water with evolving hydrogen. In the present work the oxidation rate of activated aluminium and water is investigated depending on eutectic composition, reaction temperature, and powder particle size. The mechanism of the main eutectic's components influence on the reacting ability of aluminium is discussed. (author)

2008-06-15

352

Activated charcoal from coconut shell using ZnCl{sub 2} activation  

Energy Technology Data Exchange (ETDEWEB)

In this study attempts have been made to utilize biomass residues in a proper and efficient way. As a part of these attempts activated charcoal has been produced from coconut shell. The effects of temperature, time and impregnation ratio on activation and yield have also been studied. Experimental results show that higher temperature produces better activation but lower yield. The optimum values for activation time and impregnation ratio in producing activated charcoal were 50 min and 40%, respectively, at 600{sup o}C. (Author)

2002-05-01

353

Zinc-blende--wurtzite polytypism in semiconductors  

Science.gov (United States)

The zinc-blende (ZB) and wurtzite (W) structures are the most common crystal forms of binary octet semiconductors. In this work we have developed a simple scaling that systematizes the {ital T}=0 energy difference {Delta}{ital E}{sub W{minus}ZB} between W and ZB for all simple binary semiconductors. We have first calculated the energy difference {Delta}{ital E}{sub W{minus}ZB}{sup LDF}({ital AB}) for AlN, GaN, InN, AlP, AlAs, GaP, GaAs, ZnS, ZnSe, ZnTe, CdS, C, and Si using a numerically precise implementation of the first-principles local-density formalism (LDF), including structural relaxations. We then find a {ital linear} scaling between {Delta}{ital E}{sub W{minus}ZB}{sup LDF}({ital AB}) and an atomistic orbital-radii coordinate {ital {tilde R}}({ital A},{ital B}) that depends only on the properties of the free atoms {ital A} and {ital B} making up the binary compound {ital AB}. Unlike classical structural coordinates ...

1992-10-15

354

Trace element analysis in CRM of plant origin by inductively coupled plasma mass spectrometry  

International Nuclear Information System (INIS)

Three CRMs of plant origin (SRM 1515 Apple Leaves, SRM 1570a Trace Elements in Spinach Leaves, and SRM 1575 Pine Needles) were used for analytical quality assurance of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, and Pb determination by ICP-MS. The samples were decomposed using microwave assisted pressurized digestion by HNO_3 and HNO_3 + H_2O_2 mixture and temperature programmed dry ashing. Concentrations of elements in samples were evaluated by external calibration. All samples, blanks, and standards were spiked to 100 #mu#g/L concentration of In and Bi as internal standards. During the measurement, signals of "5"2Cr, "5"3Cr, "5"4Fe, "5"5Mn, "5"9Co, "6"0Ni, "6"2Ni, "6"3Cu, "6"5Cu, "6"6Zn, "9"5Mo, "1"1"1Cd, "1"1"2Cd, "1"1"5In, "2"0"6Pb, "2"0"7Pb, "2"0"8Pb and "2"0"9Bi were monitored. Results of Pb, Cd, Cu, Zn, Mo and Co determination were in good agreement with certified values. In order to obtain accurate results for As at low ...

1997-04-21

355

Thermal annealing effect on optical properties of electrodeposited ZnO thin films  

Energy Technology Data Exchange (ETDEWEB)

ZnO thin films were electrodeposited in aqueous solution on gilded p-type Si wafer substrates. Thermal treatments were carried out on different films in Ar atmosphere at different temperatures, between 200 and 600 {sup 0}C. Surface morphology studies using scanning electron microscopy and atomic force microscopy show a smooth surface for an annealing temperature of 400 {sup 0}C with a roughness mean square value of about 15 nm and a precipitation of ZnO microcrystals on the deposit surface at 600 {sup 0}C. X-ray diffraction experiments reveal a decrease in the c-parameter value from 5.223 to 5.206 A after treatment at 600 {sup 0}C, due to the removal of hydrogen from the film. Raman spectroscopy analyses show an improvement in the crystal quality of the film and a decrease in the compressive stress inside the deposit. Photoluminescence observations reveal an important change in the UV emission band after annealing at 200 {sup 0}C. A visible ...

2008-10-07

356

The interaction of Np(V), Pu(VI) and Tc(VII) with metal in alkaline solutions  

International Nuclear Information System (INIS)

The interaction of Np(V), Pu(VI) and Tc(VII) with metal reductants Zn, Cr, Sn and their alloys was investigated in 0.5-4 mol l"-"1 NaOH solutions in static and dynamic conditions (by filtration of solutions through the column filled with grains of metal). In this paper, it was found that the reduction and succeeding precipitation hydroxides of these elements, on the surface of metal grains from 0.5 to 4 mol l"-"1 NaOH solutions, gives a decontamination factor (DF) from 1.1 to 67. The best result was achieved for Pu (DF=67) on Cr grains after 2.5 h contact at 60 C with 0.5 mol l"-"1 NaOH solution containing Pu(VI). Increasing the NaOH concentration, and the addition of chromate ions and complex-forming agents to alkaline solution results in a decrease of the decontamination factor (DF). A better result for Np sorption from 1 mol l"-"1 NaOH solutions was achieved after longer contact, than for Pu, with Cr and Zn grains. The maximum DF=8.9 was ...

1998-06-12

357

Production and characterisation of the transition metal chalcogenides MoS[sub 2], MoSe[sub 2], WS[sub 2] and WSe[sub 2] as thin films in photovoltaics. Herstellung und Charakterisierung der Uebergangsmetallchalkogenide MoS[sub 2], MoSe[sub 2], WS[sub 2] und WSe[sub 2] als Duennfilme fuer die Photovoltaik  

Energy Technology Data Exchange (ETDEWEB)

The production and characterisation of thin films made from molybdenum sulphide, molybdenum selenide, tungsten sulphide and tungsten selenide are described. The electronic properties of the thin films were examined by Hall measurements and by thermal sensors. For the MoSe[sub 2] films, the majority of the samples were n-conducting and p-conduction was only found for a few examples. All the other films (MoS[sub 2], WS[sub 2], WSe[sub 2]) were p-conducting. The electrical transport properties of the thin films are comparable to those of single crystals. With these thin films as absorber materials, it was possible for the first time to produce the polycrystalline solid n-ZnO/p-MoSe[sub 2], n-ZnO/WSe[sub 2], n-ZnO/WS[sub 2]- and n-ITO/WS[sub 2] solar cells. In spite of not yet optimized diode geometry (lateral build-up), a maximum short circuit current of I[sub SC] = 18 mA/cm[sup 2] was achieved for the MoSe[sub 2] diode. ...

1993-01-01

358

Partitioning of trace metals in the chemical fractions of bed-load sediments of Nahr-Ibrahim river, Lebanon  

International Nuclear Information System (INIS)

Full text.Sediments are the ultimate sink of trace elements. The total metal analysis may only give information concerning possible enrichment of metals. The analysis of metal partitioning in the different chemical components of sediments (exchangeable, carbonate, easily reducible, moderately reducible, organic and residual); give a detailed information on the way in which these metals are bound to sediments, their mobilization capacity and their ability to affect water quality under different environmental conditions. The studied river basin is dominated by limestone formation, the enrichment of metals in the carbonate sediment fraction is a high probability. The objective of the study was to determine the percentage of the total metal content (Fe, Mn, Zn, Cu and Pb) in the six chemical fractions of the bed load sediments of Nahr-Ibrahim river during the dry season and verify the role of carbonate for metal sediment deposition. Bed load sediments were sampled at ...

1999-11-02

359

Minerals and trace elements determination in diets by neutron activation analysis  

International Nuclear Information System (INIS)

In the present study 12 diets, each one consisting of a pool of seven day diets, composed by four meals: breakfast, lunch, dinner and snack, adequate in energy and macro nutrients according to the RDA (Recommended Daily Allowance) recommendations, were elaborated and offered to a group of 12 men (19-42 years). The diets were collected by duplicate portion technique and dried by two different processes: freeze drying and 60 deg C ventilated oven drying. In the total, 24 diets were analyzed. The content of some minerals and trace elements (Ca, Fe, Mg, Mn, Na, Se and Zn) were determined by Instrumental Neutron Activation Analysis. The validation of methodology was made by analysis of the reference materials Typical Diet (NIST SRM 1548"a), Orchard Leaves (NIST SRM 1541) and Peach Leaves (NIST SRM 1547). The results observed by two different drying processes used were statistically compared by test T of Student. It was possible to conclude that the concentration means ...

2002-08-11

360

Depth Profiling of N and C in Ion Implanted ZnO and Si Using Deuterium Induced Nuclear Reaction Analysis  

International Nuclear Information System (INIS)

Nuclear Reaction Analysis (NRA) with deuteron ion beams has been used to probe for ion implanted nitrogen and carbon with high sensitivity in zinc oxide and silicon single crystals. The ion implanted N was measured using 1.4 MeV deuteron ion beams and was found to be in agreement with calculated values. The limit of detection for N in ZnO is 8x1014 ions cm-2. Raman measurements of the ion implanted samples showed three additional modes at 275, 504, and 644 cm-1 compared to the un-implanted ZnO crystals. The NRA and Raman results provided information on the N concentration, depth distribution, and structural changes that occur in dependence on the nitrogen ion fluences. The deuterium induced 12C(d,p)13C reaction was used to measure the carbon impurity/dose in ion implanted silicon. It was found that the use of a large cold shield (liquid nitrogen trap) in the ion implanter chamber greatly reduces the amount of carbon impurity on the surface of ...

2008-11-03

361

Crystal Structure of Human Senescence Marker Protein 30: Insights Linking Structural, Enzymatic, and Physiological Functions  

Energy Technology Data Exchange (ETDEWEB)

Human senescence marker protein 30 (SMP30), which functions enzymatically as a lactonase, hydrolyzes various carbohydrate lactones. The penultimate step in vitamin-C biosynthesis is catalyzed by this enzyme in nonprimate mammals. It has also been implicated as an organophosphate hydrolase, with the ability to hydrolyze diisopropyl phosphofluoridate and other nerve agents. SMP30 was originally identified as an aging marker protein, whose expression decreased androgen independently in aging cells. SMP30 is also referred to as regucalcin and has been suggested to have functions in calcium homeostasis. The crystal structure of the human enzyme has been solved from X-ray diffraction data collected to a resolution of 1.4 {angstrom}. The protein has a 6-bladed {beta}-propeller fold, and it contains a single metal ion. Crystal structures have been solved with the metal site bound with either a Ca{sup 2+} or a Zn{sup 2+} atom. The catalytic role of the metal ion has been ...

2010-05-25

362

Corrosion behaviors of Zn/Al-Mn alloy composite coatings deposited on magnesium alloy AZ31B (Mg-Al-Zn)  

International Nuclear Information System (INIS)

After being pre-plated a zinc layer, an amorphous Al-Mn alloy coating was applied onto the surface of AZ31B magnesium alloy with a bath of molten salts. Then the corrosion performance of the coated magnesium alloy was examined in 3.5% NaCl solution by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results showed that the single Zn layer was active in the test solution with a high corrosion rate while the Al-Mn alloy coating could effectively protect AZ31B magnesium alloy from corrosion in the solution. The high corrosion resistance of Al-Mn alloy coating was ascribed to an intact and stable passive film formed on the coating. The performances of the passive film on Al-Mn alloy were further investigated by Mott-Schottky curve and X-ray photoelectron spectroscopy (XPS) analysis. It was confirmed that the passive film exhibited n-type semiconducting behavior in 3.5% NaCl solution with a carrier density two orders of magnitude less ...

2009-12-30

363

Azathia crown ethers carrying pyrene pendant as receptor molecules for metal sensor systems  

International Nuclear Information System (INIS)

A series of crown ethers carrying a pyrene group with nitrogen-sulfur donor atoms, that differ in having three, four and five sulfur atoms in the macrocycle was designed and synthesized by the reaction of the corresponding macrocyclic compound and 1-bromomethylpyrene. The influence of metal cations such as Mn2+, Fe2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Pb2+ and Al3+ on the spectroscopic properties of the ligands was investigated in acetonitrile-dichloromethane (1:1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Fe2+, Zn2+, Cu2+, Pb2+ and Hg2+. The results of spectrophotometric titration experiments disclosed the complexation compositions and complex stability constants of the novel ligands with Fe2+, Zn2+, Cu2+, Pb2+ and Hg2+ cations. The monoazatetrathia crown ether showed good sensitivity for Cu2+ with linearity in the range ...

2011-04-01

364

Assimilation of cadmium, chromium, and zinc by the green mussel Perna viridis and the clam Ruditapes philippinarum  

Energy Technology Data Exchange (ETDEWEB)

The green mussel Perna viridis and the clam Ruditapes philippinarum have been frequently used as biomonitors of coastal contamination in subtropical and tropical waters, yet the physiological processes controlling metal uptake in these bivalves are unknown. Assimilation efficiency (AE) is an important physiological parameter quantifying metal bioavailability from ingested food. The authors determined the AEs of Cd, CR, and Zn in these bivalves feeding on five species of phytoplankton and one natural section. The influences of the cytoplasmic distribution of metals in the algal cells and the digestive physiology of bivalves on metal AEs were also examined. Among the three metals, Zn was generally assimilated at the highest efficiency, i.e., 21 to 36% in the mussels and 29 to 59% in the clams. Cr was the least assimilated metal, with AEs being 10 to 16% in the mussels and 11 to 24% in the clams. The AEs of Cd and Zn in the ...

2000-06-01

365

Use of natural gas on heavy duty vehicles in Brazil: experience, current scene and barriers that still persist; Utilizacao do gas natural em veiculos pesados no Brasil: experiencia, cenario atual e barreiras que ainda persistem  

Energy Technology Data Exchange (ETDEWEB)

In the 80's, because of the oil crisis, the Natural Gas (NG) appeared as a fuel with a great potential for Diesel replacement in Heavy Duty Vehicles. At that time, PETROBRAS with other companies have developed partial conversion technologies from Diesel to NG, known as 'Dual Fuel'. Engine dynamometer and vehicle bus tests have been developed to verify its technical and economical viability. Because of several factors, the Dual Fuel Program did not advance and the experience was interrupted. At the same time, other experiences using NG Otto Cycle bus engines, manufactured in Brazil, have been conducted, mainly at Sao Paulo, nevertheless, without expansion. Currently, factors as increase of the NG converted light vehicles fleet; the NG excess in the National Market, which has contributed to the NG distribution net expansion; the Environmental Legislature in vigor, that continuously determine lower emission limits; the government interest in increasing the NG ...

2004-07-01

366

The biofuels excellence network; Rede de excelencia em biocombustiveis  

Energy Technology Data Exchange (ETDEWEB)

The organization of the Biofuels Excellence Network, inside PROMINP - the Program of Mobilization of the National Industry of Oil and Natural Gas, has the objective of improving the actions of technical innovation and management in the chain of Oil, Gas Natural and Biofuels, through the optimized use of physical, financial, technological resources, of information and staff, with maximum qualification in areas of the human knowledge, whose purpose is to make decisions on specific problems of improvement of processes and/or products, besides promoting actions for the development and reinforcement of the markets of ethanol and biodiesel. The organization of the Biofuels Excellence Network became necessary, in order to enable Brazil to reach vanguard standards in biofuels (ethanol and biodiesel) in a sustainable, competitive and environmentally responsible way. Among the main reasons for the creation of the Biofuels Excellence Network are: to speed up the acquisition of knowledge and ...

2008-07-01

367

Synchrotron Self-Compton Analysis of TeV X-ray Selected BL Lacertae Objects  

CERN Document Server

We introduce a methodology for analysis of multiwavelength data from X-ray selected BL Lac (XBL) objects detected in the TeV regime. By assuming that the radio--through--X-ray flux from XBLs is nonthermal synchrotron radiation emitted by isotropically-distributed electrons in the randomly oriented magnetic field of a relativistic blazar jet, we obtain the electron spectrum. This spectrum is then used to deduce the synchrotron self-Compton (SSC) spectrum as a function of the Doppler factor, magnetic field, and variability timescale. The variability timescale is used to infer the comoving blob radius from light travel-time arguments, leaving only two parameters. With this approach, we accurately simulate the synchrotron and SSC spectrum of flaring XBLs in the Thomson through Klein-Nishina regimes. Photoabsorption by interactions with internal jet radiation and the intergalactic background light (IBL) is included. Doppler factors, magnetic fields, and absolute jet powers are obtained by ...

2008-01-01

368

Separation of the components of the binary mixture ethanol-water by steam flux in solid phase column; Separacao dos componentes da mistura binaria etanol-agua por passagem do vapor em coluna de fase solida  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the energy required to separate ethanol from an aqueous solution in a distillation column containing a solid phase. The solid phases evaluated consisted of either an amylatious (ground corn) or a cellulose (sugar cane bagasse) absorber whit particle sizes smaller than 4 mm. The water-retention capacity of each solid phase was measured by passing vapors or ethanol-water mixtures through the solid phase. When starting with initial concentrations bellow the azeotropic point, ethanol concentrations up to 99,5% (on corn) and 97,2% (on sugar cane) were achieved. The water content was evaluated potentiometrically (Karl`Fischer). Regarding the 2-4 mm ground corn solid phase column, the energy consumed was estimated to be reduced by 15,6% and 60% (by weight) ethanol-water mixture respectively. (author) 11 refs., 2 figs., 2 tabs

1987-12-31

369

Ruthenium-106 brachytherapy for uveal melanomas. Preliminary results: a single institutional experience; Braquiterapia com rutenio-106 em melanomas uveais. Resultados preliminares: experiencia uni-instuticional  

Energy Technology Data Exchange (ETDEWEB)

Objective: To analyze the early response of uveal melanomas in patients treated with ruthenium-106 brachytherapy. Materials And Methods: In the period between April 2002 and July 2003, 20 patients diagnosed with uveal melanoma were submitted to ruthenium-106 brachytherapy. The calculated dose delivered at the apex of the tumor ranged between 55 Gy and 100 Gy. Patients with lesions greater than 5 mm were submitted to transpupillary thermotherapy concomitantly with ophthalmic plaque insertion. Results: As regards the lesions site, 75% of the lesions were located in the choroid, 15% in the iris, and the remainder 10% in the ciliary body. In a median 19-month-follow-up, the progression-free survival for brachytherapy was 69%, and 87% for associated brachytherapy and transpupillary thermotherapy. A significant tumor height reduction was observed after treatment. No patient was submitted to enucleation. Conclusion: Our preliminary results show that ruthenium-106 brachytherapy is an ...

2007-03-15

370

Reverse time migration: resolution in cross well seismic surveys; Migracao reversa no tempo: resolucao em levantamentos sismicos interpocos  

Energy Technology Data Exchange (ETDEWEB)

The standards mapping methods are limited by the lack of information between surface measures and wells profiles. The cross well seismic survey has proven being an effective high-resolution method for reservoirs characterization due its high frequency band. In this work, a 2-D finite differences algorithm for numerical cross well seismic simulation was developed, based in the approach of 2nd order for the time derivatives and 4th order for the space derivatives. In relation to the imaging techniques, it was introduced a reverse time migration method based in the solutions of the wave equation in time for cross well seismic data by the method of the finite differences exclusively. The results of reverse time migration has showed that layers with 90 cm thickness for P-waves could be visualized in migrated sections with excellent resolution. The high frequency cross well seismic data combined with reverse time migration have the potential for revealing never seeing reservoir details using ...

2003-07-01

371

Proximal cholangiocarcinoma. Prognostic factor and effectiveness of post operative radiotherapy  

International Nuclear Information System (INIS)

To define the prognostic factors after surgical resection and evaluate the effectiveness of Post Operative Radiotherapy (PORT) in cases with cholangiocarcinoma, 44 cases with proximal cholangiocarcinoma were examined. The mean observation period was 20.6 months, and the survival rates 1, 3 and 5 years after the resection were 79.9%, 59.8% and 39.3%, respectively. Univariate analysis revealed that the presence of lymph node metastasis and absence of PORT were significant poor prognostic factors. Multivariate analysis revealed that the absence of PORT was a significant poor prognostic factor. The survival rates for 1 and 3 years after the resection were 80.0% and 40.0% in the curable A/B and PORT (-) group, and 100% and 53.3% in curable C and PORT (+) group. There were no local reccurences in the pathologically classified hm2 and em2 patients who underwent PORT. Even when the surgical margin is positive for the carcinoma pathologically, it is possible to avoid local ...

2000-10-01

372

Piperidine adsorption on two different silver electrodes: A combined surface enhanced Raman spectroscopy and density functional theory study  

Energy Technology Data Exchange (ETDEWEB)

The surface enhanced Raman scattering (SERS) spectra of piperidine in silver colloid solution, on roughened silver electrode and on roughened silver electrode modified with silver nanoparticles were studied, and the high-quality SERS spectra of piperidine on roughened silver electrode modified with silver nanoparticles were obtained for the first time. Surface selection rules derived from the EM enhancement model were employed to deduce piperidine orientations on the different surfaces. On the basis of this, two models of piperidine adsorbed on the surface of the silver nanoparticles were built, and DFT-B3PW91/LanL2dz was applied to calculate the Raman frequencies. It proves that, at higher potential values, the piperidine is perpendicularly standing on the roughened silver electrode surface though its lone-electron pair, but in silver colloid solution and on the silver nanoparticles modified silver electrode the piperidine molecular lies flat on the silver ...

2007-10-15

373

Performance evaluation of the conventional Brazilian industries radiation protection in the small industrial gauges and industrial radiography areas; Sistema de avaliacao de desempenho em radioprotecao das industrias convencionais brasileiras nas areas de medidores nucleares e radiografia industrial  

Energy Technology Data Exchange (ETDEWEB)

This works evaluates by punctuation the performance in conventional Brazilian industries radiation protection area which make use of small industrial gauges and industrial radiography. It proposes, procedures for industry self-evaluation, besides a new radiation protection plans pattern for the small industrial gauges area. The data source where inspection reports of Dosimetry Radiation Protection Institute/Nuclear Energy Commission conventional Brazilian industries' radiation protection plans, beyond visitation to the inspection place. The performance evaluation has been realized both in the administrative and operational aspects of the industries. About of 60% of the industries have a satisfactory register control which does not happen to the operational control. The performance evaluation advantage is that industries may self-evaluate, foreseeing Dosimetry Radiation Protection Institute's regulation inspections, correcting its irregularities, automatically ...

1999-08-01

374

Partial Isometries of a Sub-Riemannian Manifold  

CERN Document Server

In this paper, we obtain the following generalisation of isometric $C^1$-immersion theorem of Nash and Kuiper. Let $M$ be a smooth manifold of dimension $m$ and $H$ a rank $k$ subbundle of the tangent bundle $TM$ with a Riemannian metric $g_H$. Then the pair $(H,g_H)$ defines a sub-Riemannian structure on $M$. We call a $C^1$-map $f:(M,H,g_H)\\to (N,h)$ into a Riemannian manifold $(N,h)$ a {\\em partial isometry} if the derivative map $df$ restricted to $H$ is isometric; in other words, $f^*h|_H=g_H$. The main result states that if $\\dim N>k$ then a smooth $H$-immersion $f_0:M\\to N$ satisfying $f^*h|_H

2010-01-01

375

Monitoring the Effect of Longwall Mining on Agricultural Environments - Interim Report  

Energy Technology Data Exchange (ETDEWEB)

The project was designed to quantify the impacts of longwall mine subsidence (LWMS) on the production and quality of agricultural vegetated environments. This project utilised a variety of traditional ground based sampling techniques including biomass harvests and estimates, leaf area index (LAI), pasture height, species composition and soil sampling along with proximal sensor data capture using a Crop Circle{trademark} and an EM38. Satellite imagery was collected using the Quickbird satellite and the high resolution imagery was used to monitor large areas of LWMS affected areas and adjacent un-mined land. Two landscapes were investigated using a whole of mine site technique including remote sensing, ground survey and traditional agricultural monitoring methods. The landscapes were at the Kestrel site in Emerald, QLD including a forage sorghum and an improved pasture and at Beltana in the Hunter Valley, NSW including an irrigated lucerne pasture and an unimproved ...

2009-06-15

376

Models comparative study for heat storage in fixed beds; Estudo comparativo de modelos para armazenamento de calor em leitos fixos  

Energy Technology Data Exchange (ETDEWEB)

This work presents comparative results of a numerical investigation of four possible models for the prediction of thermal performance of fixed bed storage units and their thermal design. These models includes Schumann's model, the radial dispersion model, a model that include both axial heat conduction in the fluid phase and admits thermal gradient in the solids particles and finally a two dimensional single phase model. For each of these models a computer code was written and tested to evaluate the computing time of same data and analyze any other computational problems. The tests of thermal performance included particle size, porosity, particle material, flow rate, inlet temperature and heat losses form tank walls and extremities. Dynamics behaviour of the storage units due to transient variation in either flow rate or inlet temperature was also investigated. The results presented include temperature gradients, pressure drop and heat storage. The results obtained are very ...

1991-07-01

377

Measurement-while-drilling (MWD) development for air drilling  

Energy Technology Data Exchange (ETDEWEB)

The objective of this program is to tool-harden and make commercially available an existing wireless MWD tool to reliably operate in an air, air-mist, or air-foam environment during Appalachian Basin oil and gas directional drilling operations in conjunction with downhole motors and/or (other) bottom-hole assemblies. The application of this technology is required for drilling high angle (holes) and horizontal well drilling in low-pressure, water sensitive, tight gas formations that require air, air-mist, and foam drilling fluids. The basic approach to accomplishing this objective was to modify GEC's existing electromagnetic (e-m) CABLELESS''{trademark} MWD tool to improve its reliability in air drilling by increasing its tolerance to higher vibration and shock levels (hardening). Another important aim of the program is to provide for continuing availability of the resultant tool for use on DOE-sponsored, and other, air-drilling programs.

1992-01-01

378

Material and process improvements in condenser tubing  

Energy Technology Data Exchange (ETDEWEB)

The reliability of the surface condenser is a key factor in plant performance level and maintenance cost optimization. This is especially the case for thermal nuclear plants where condenser raw wa-ter ingress can introduce contamination into the chemically-controlled, steam/water loop potentially causing damage to sensitive equipment. Two important parameters must be taken into account when attempting to optimize the quality and the reliability of condenser tubing. They include selecting the appropriate material according to the cooling water corrosion level present. A second and equally important parameter is the manufac-turing of the tubing product itself. This paper will identify methods to optimize manufacturing processes and improve tubing quality, according to VALTIMET's 30 years of condenser welded tubing production experience. Those methods complete the core manufacturing process (forming and welding), through improvement of the metallurgical homogeneity (Roll Sink ...

2010-07-01

379

Magnetic moment measurements of gadolinium, holmium and ytterbium tartrate trihydrate crystals  

British Library Electronic Table of Contents (United Kingdom)

Magnetic moment and susceptibility of single crystals of rare earth tartrates of the type R(C4H4O6)(C4H5O6)3H2O (where R = Gd, Ho, and Yb), using a vibration sample magnetometer are reported. The experimental values of molar susceptibilities for Gd(C4H4O6)(C4H5O6)3H2O, Ho(C4H4O6)(C4H5O6)3H2O, and Yb(C4H4O6)(C4H5O6)3H2O are 2.58x10-2, 4.66x10-2, and 8.03x10-3 (in cgs em units), respectively. The calculated effective magnetic moments are in good agreement with the theoretical predictions on rare earth ions.

2008-01-01

380

Generalized Collective Inference with Symmetric Clique Potentials  

CERN Document Server

Collective graphical models exploit inter-instance associative dependence to output more accurate labelings. However existing models support very limited kind of associativity which restricts accuracy gains. This paper makes two major contributions. First, we propose a general collective inference framework that biases data instances to agree on a set of {\\em properties} of their labelings. Agreement is encouraged through symmetric clique potentials. We show that rich properties leads to bigger gains, and present a systematic inference procedure for a large class of such properties. The procedure performs message passing on the cluster graph, where property-aware messages are computed with cluster specific algorithms. This provides an inference-only solution for domain adaptation. Our experiments on bibliographic information extraction illustrate significant test error reduction over unseen domains. Our second major contribution consists of algorithms for ...

2009-01-01

381

Facial osteomyelitis as complication of chronic sinusitis in hemophiliac-AIDS patients - scintigraphic evaluation with technetium-99m-MDP and Gallium-67; Osteomielitis da face como complicacao de sinusite cronica em hemofilicos aideticos - avaliacao cintilografica com {sup 99m} Tc-MDP e {sup 67} Ga  

Energy Technology Data Exchange (ETDEWEB)

In the paper six cases of facial osteomyelitis as a complication of chronic sinusitis in hemophiliac-AIDS patients are reported. Osteomyelitis was suggested by an increasing of erythrocyte sedimentation rate. The diagnosis was confirmed by a positive {sup 99m} Tc MDP scintigraphy. The patients were submitted to clinical treatment. The erythrocyte sedimentation rate and 67-gallium citrate scans were used in the follow-up of the therapy. Three patients had negative gallium after three weeks of organism-specific antibiotic therapy; in two patients the gallium scintigraphy remained positive. One patient did not undergo the radionuclide scan for this clinical conditions. These results suggest that MDP scans showed higher sensitivity and specificity in detection of bone disease in chronic sinusitis. Gallium scans appeared to be valuable tool in the follow-up of the infection. There are no reports in the literature of osteomyelitis as a complication of chronic sinusitis in AIDS patient. ...

1997-01-01

382

Exemplification of the Game Theory application in auctions of exploratory blocks; Um exemplo de aplicacao de Teoria dos Jogos em leiloes de blocos exploratorios  

Energy Technology Data Exchange (ETDEWEB)

This article describes a methodology to determine the best strategy in an open bid, where oil and gas fields are the targets for exploration. Based upon the previous bid rounds for a given specific area - the Campos Basin, for that matter -, the data were statistically treated to fit a probability density function, modelling the value of bids offered by the competing companies. By means of techniques and concepts pertaining to Game Theory a balance matrix was built for values of bids made by companies as a function of the company alone in assumed bid rounds. At the end of each british auction, participants of this simultaneous game, using the rationality principle, aimed at winning the tender on the oil field aimed for, through the use of better answers with respect to its rival competitor. The game goal was maximize return on investment purchase in the decisions of lease blocks purchases in the auctions, or to try minimize its opponents gains. Proceeding with the work, this time, ...

2003-07-01

383

Evaluation of the increase of superficial dose due to thermoplastic immobilizing in radiotherapy; Avaliacao dos efeitos de superficializacao de dose por imobilizadores termoplasticos em radioterapia  

Energy Technology Data Exchange (ETDEWEB)

Perforated thermoplastic masks are used to provide patients immobilization. This procedure inserts a material in the path of the radiation beam, that attenuates and modifies the beam fluence and flatness. The present study evaluates the increase in skin dose as a result of using thermoplastic masks. Relative doses were measured on the surface of a solid water phantom, in the presence and absence of masks. These masks were stretched according to deformation patterns observed in clinical routine. The measurements were obtained with a plane-parallel chamber (Markus type 23343) and radiochromic film (EBT Gafchromic) for 6MV X-rays from a linear accelerator, and for a radiation beam from a cobalt therapy unit. The results showed that thermoplastic masks, whose thickness varied between 2 and 3 mm, increased the dose on the surface by a factor of 3. Due to the variations in the skin dose distribution, clinical procedures were suggested to minimize radiobiological damages in subcutaneous ...

2010-07-01

384

Evaluation of specific consumption from the use of chicken oil biodiesel in one cylinder generator set; Avaliacao do consumo especifico a partir da utilizacao de biodiesel de oleo de frango em um grupo-gerador monocilindrico  

Energy Technology Data Exchange (ETDEWEB)

Biodiesel can be produced from numerous materials, including by-products of animal chain. In this scenario, the chicken's oil, that is located and an environment not explored for biodiesel production, can be a good alternative in South and Southeast Brazilian Region, where they are slaughtered around 9.100.000 chickens per day. In order to determine the specific consumption from a generator set with single cylinder 6.6 kW of power and generation capacity of 5 kW, using chicken oil biodiesel (B-100), were performed the bench test using a auxiliary tank, precision scale and an energy analyzer. Were conducted four treatments (25%, 50%, 75% and 100% of generating capacity). The worst SC was the engine at 25% of generation capacity (1.5 kW) and better with 75% of maximum load (3.75 kW) with a mean of 479.34 g kWh{sup -1}. By Turkey's test ant 5% probability there was a significant difference only for the first treatment. (author)

2010-07-01

385

Evaluation of red mud as pozzolanic material in replacement of cement for production of mortars; Avaliacao da lama vermelha como material pozolanico em substituicao ao cimento para producao de argamassas  

Energy Technology Data Exchange (ETDEWEB)

Red mud is a by-product of the alkaline extraction of aluminum from the bauxite and represents a renewed environmental problem due the significant annual throughput by the plants. In the present work, the pozzolanic properties of Brazilian red mud fired at 600, 700, 800 and 900 deg C were investigated by monitoring lime consumption using DTA analysis and Brazilian standard methodology NBR 5772 (1992). Products and kinetics of hydration were determined in cement pastes produced with 5 and 15% red mud using x-ray diffraction and DTA analysis. Compressive strength and capillary absorption tests were realized on mortars constituted by 5, 10 and 15% red mud in replacement of cement. When calcined at 600 deg C, the red mud develops good pozzolanic properties, and the compressive strength of mortars produced with this waste meet values in accordance with regulatory standard. These results shown than red mud can be used, in partial replacement of cement, as new construction material to produce ...

2010-07-01

386

Effects of morpho dynamics in shallow waters over pipeline facilities; Efeitos da morfodinamica em aguas rasas sobre instalacoes de dutos  

Energy Technology Data Exchange (ETDEWEB)

The success in developing of the oil industry operating in offshore-onshore terminals, connected by pipelines with the facilities of the coastal zone, can be attributed partially to the beach morpho dynamic monitoring. This study represents a solution to the concerns of the technical operations in coastal zones because it minimizes the impact of the petroleum production and it assures the environmental protection associated to the risks of the pipelines breaking. This impact type results mainly of the vertical and horizontal displacements of the beach, from the coastal dunes to the shore face. The mobility of the profile is associated to the magnitude of the sedimentary processes, which reproduce naturally or not, in scale of time that can vary among few days, years or decades. For the monitoring and interpretation of the beach profile mobility the following methods are recommended: calculation of the closure depth with base in the wave data; bathymetric survey with sled; calculation ...

2003-07-01

387

Determination of the initial energy in computerized tomography with proton beams; Determinacao da energia inicial em tomografia computadorizada com feixe de protons  

Energy Technology Data Exchange (ETDEWEB)

In earliest works devoted to proton computed tomography it was shown that the advantage of pCT image reconstruction appears when the energy is close to the Bragg peak region, since the proton passes the object. This effect provided by the Bragg peak makes the computerized tomography with protons possible. However, when decreasing the initial proton energy, with the increase of the irradiation dose, there are two effects that work simultaneously in opposite ways. First, the energy loss of a proton in an object becomes bigger at small initial energy. At the same time decreasing of the proton energy results in the increase of the energy straggling, requiring a larger number of protons. In this work the radiation dose dependence on the proton initial energy was studied using analytical formulas and computer simulations. The investigation determined that the radiation dose practically does not depend on the initial energy, except in the energy region very close to the minimum energy ...

2007-07-01

388

Core Heat Transfer Model Validation of the TASS/SMR-S Code using the Bennett's Test  

International Nuclear Information System (INIS)

The SMART (System-integrated Modular Advanced ReacTor) which is a 330 MWt advanced integral PWR was developed by the KAERI (Korea Atomic Energy Institute) for electricity generation and seawater desalination. A thermal hydraulic evaluation and analysis of the SMART is performed by the TASS /SMR-S (Transient And Setpoint Simulation/System integrated Modular Reactor-Safety). The TASS/SMR-S code has various models reflecting the design features of the SMART such as the drift flux model, the core models (core power and core heat transfer model), the component models, and the specific models. One of the core models is the core heat transfer model. The role of this model is to calculate the heat flux and radial temperature profiles at a fuel rod surface using the relevant heat transfer correlations for all of the heat transfer modes. Also it is modeled to meet the requirements of the 10 CFR 50 appendix K EM model for the CHF (Critical Heat Flux) and post CHF conditions. ...

2010-10-01

389

Computing Good Nash Equilibria in Graphical Games  

CERN Document Server

This paper addresses the problem of fair equilibrium selection in graphical games. Our approach is based on the data structure called the {\\em best response policy}, which was proposed by Kearns et al. \\cite{kls} as a way to represent all Nash equilibria of a graphical game. In \\cite{egg}, it was shown that the best response policy has polynomial size as long as the underlying graph is a path. In this paper, we show that if the underlying graph is a bounded-degree tree and the best response policy has polynomial size then there is an efficient algorithm which constructs a Nash equilibrium that guarantees certain payoffs to all participants. Another attractive solution concept is a Nash equilibrium that maximizes the social welfare. We show that, while exactly computing the latter is infeasible (we prove that solving this problem may involve algebraic numbers of an arbitrarily high degree), there exists an FPTAS for finding such an equilibrium as long as the best ...

2007-01-01

390

Cogeneration in air separation cryogenic plants; Cogeracao em plantas criogenicas de separacao de ar  

Energy Technology Data Exchange (ETDEWEB)

A thermal and economic study, carried on by using the first and second law of thermodynamics concepts demonstrated the economic feasibility of the cogeneration system, and proposed modifications to be done in the studied cryogenic plant, a typical T-240 NA MPL3 plant. The thermodynamic analysis showed that the second law efficiency of the processes could be improved, together with a 12% electric energy consumption reduction. Four cogeneration schemes were analyzed with both the first and second laws of thermodynamics and, then, the economic analysis was performed. Rankine, Brayton, Otto and Combined gas-steam basic cycles were used in this analysis.The combined gas-steam cycle was shown to be more economically feasible than others. Thermal and electric loads were well balanced, resulting in a higher second law efficiency. Although the initial investment for the modification was higher, the savings resulted to be higher, turning into a higher rate of return of the investment. (author)

2000-07-01

391

Cavity detection based on EM migration of TEM data; TEM ho data no denji migration ni yoru kudo kenshutsu no kokoromi  

Energy Technology Data Exchange (ETDEWEB)

With an objective to discuss applicability of resistivity imaging using electromagnetic migration to detection of underground cavity, an applicability test was carried out on calculation of a numerical model and measurement data. By using the numerical model, a calculation was performed on a hypothetical case that a cubic cavity with sides each at 40 m exists in a homogenous medium of 200 ohm-m, with the cavity top located 20 m below the ground surface. As a result, it was possible to structure in a very short calculation time an image of the cavity which cannot be identified by one-dimensional inverse analysis. In the case of this cavity, a center of the image was structured on its lower face. It was shown that a location to indicate the image must be changed according to difference in the measurement locations. In a test on data measured in an underground cavity in the city of Utsunomiya, Tochigi Prefecture, it was found that the result may vary largely depending on structure of the ...

1997-05-27

392

Bioremediation process in impacted area of petroleum activities; Processos de biorremediacao em areas influenciadas por atividades petroliferas  

Energy Technology Data Exchange (ETDEWEB)

The present work's objective is to test sampling methodologies applied on the bioremediation processes in situ, involving the establishment of sample replicates, specific laboratory procedures and its results, inedited on the referred technique. Agricultural fertilizers were used, NPK and OSMOCOTE, as biostimulants on mangroves substrates affected by petroleum activities. The tested methodology used on the experiment was based on the monitoring of this technology in aquarium with water from Sao Paulo's river and sediment contaminated by oil, realized in three steps (first pre-test, second pre-test and third pre-test) that happened between the months of August and November of 2007. The physical-chemical parameters were measured with portable devices carefully calibrated and the oil analyzed with gas chromatography. The saturated hydrocarbons (n-alkenes) had an increase on the concentrations for some aquariums and these found results do not permit to confirm if the ...

2008-07-01

393

An efficient method for 3-D pre stack migration in time reverse-time depth by using finite difference method; Um metodo eficiente para migracao pre-empilhamento 3-D em profundidade reversa no tempo pelo metodo das diferencas finitas  

Energy Technology Data Exchange (ETDEWEB)

Much of the current technology on 3D-prestack depth migration is based on the Kirchhoff method and the traveltime information needed for this purpose is obtained by the ray-theory approximation. The main motivation driving these options is to reduce computations but it can also have an adverse effect on the quality of results. Experience with real data indicates that the corresponding poststack data migrated by the reverse-time method often yields superior results. Considerable computational efficiency can be obtained by employing nonuniform coarse grid spacing during the reverse-time migration. We followed this strategy for developing a parallel scheme for doing 3D- prestack depth migration. However, we worked only on a small subset of shot gathers whose determined by the Quasi-Monte Carlo method. The results were indistinguishable from those obtained by using a much larger population of uniformly spaced shot gathers. We present examples of migration of 3-D data. (author)

1997-07-01

394

A single sorbent for tetracycline enrichment and subsequent solid-matrix time-resolved luminescence  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study was to search for a sorbent that could act as an extraction phase and as a support for solid-matrix time-resolved luminescence (SMTRL). Four potential sorbents were investigated for this purpose using tetracycline (TC) as a model analyte. Sorbents prepared from C18 silica gel or calcium cross-linked pectin gel were able to extract TC from dilute solutions. Europium(III)-TC complex adsorbed on the surface of C18 generated the most intense TRL signal when measured at {lambda}{sub ex} = 388 nm and {lambda}{sub em} = 615 nm. This method achieved a 1 ng/ml limit of detection (LOD) with a 100 {mu}l sample solution in a repeated spotting mode. Hyphenation of sorbent extraction and SMTRL was demonstrated using C18. This method is suitable for screening of TC in foods or aqueous solutions and can be extended to other luminescent lanthanide-chelating analytes in physiological or environmental samples.

2005-01-10

395

Proposal of procedures to prevent errors in radiotherapy based in learned lessons of accidental expositions; Proposta de procedimentos para evitar erros em radioterapia baseados em licoes aprendidas de exposicoes acidentais  

Energy Technology Data Exchange (ETDEWEB)

In order to consider some procedures to prevent errors in radiotherapy based in learned lessons of accidental expositions and in accordance with information contained in international reports elaborated by International Atomic Energy Agency (IAEA) and of the data base availability by the European group Radiation Oncology Safety Information System (ROSIS) on the events, a research of the occurred errors was performed. For the evaluation of the incidents a data base based in the ROSIS and added plus a parameter was created 'type of error'. All the stored data make possible the evaluation of the 839 incidents in terms of frequency of the type of error, the process of detention, the number of reached patients and the degree of severity. Of the 50 types of found errors, the type of error more frequently was 'incorrect treatment coordinate', confirmed with the data of literature and representing 28,96 por cent of the total of the incidents. The results ...

2007-07-01

396

MENDING THE IN SITU MANIPULATION BARRIER  

Energy Technology Data Exchange (ETDEWEB)

In early 2004, the U.S. Department of Energy (DOE) Richland and Fluor Hanford requested technical assistance from the DOE Headquarters EM-23 Technical Assistance Program to provide a team of technical experts to develop recommendations for mending the In Situ Redox Manipulation (ISRM) Barrier in the 100-D Area of the Hanford Site in Washington State. To accommodate this request, EM-23 provided support to convene a group of technical experts from industry, a national laboratory, and a DOE site to participate in a 2 1/2-day workshop with the objective of identifying and recommending options to enhance the performance of the 100-D Area reactive barrier and of a planned extension to the northeast. This report provides written documentation of the team's findings and recommendations. In 1995, a plume of dissolved hexavalent chromium [Cr(VI)], which resulted from operation of the D/DR Reactors at the Hanford site, was discovered along the ...

2006-02-06

397

Uptake of radiolabeled ions in normal and ischemia-damaged brain  

Energy Technology Data Exchange (ETDEWEB)

The regional concentrations of nine radiochemicals were measured in rat brain after induction of cerebral ischemia to identify tracers concentrated by brain undergoing selective neuronal necrosis. Transient (30 minute) forebrain ischemia was produced in the rat; 24 hours after cerebral recirculation the radiochemicals were injected intravenously and allowed to circulate for 5 hours. The brain concentrations of the radiochemicals in dissected regions were determined by scintillation counting. Forebrain ischemia of this nature will produce extensive injury to striatal neurons but will spare the great majority of neocortical neurons at 24 hours. The regional concentrations of these radiochemicals varied considerably in both control and ischemic animals. In postischemic animals, 4 radionuclides (/sup 63/Ni, /sup 99/TcO/sub 4/, /sup 22/Na, and (/sup 3/H)tetracycline) were concentrated in the irreversibly damaged striatum in amounts ranging from 1.4 to 2.4 times greater than in normal ...

1986-05-01

398

Vanadium based amorphous mixed oxides used as negative electrodes of lithium batteries; Oxydes mixtes amorphes a base de vanadium comme electrodes negatives de batteries au lithium  

Energy Technology Data Exchange (ETDEWEB)

This paper presents recent results concerning the chemical and electrochemical synthesis, the electrochemical properties and the characterization of two new families of amorphous oxides of formula Li{sub x}MVO{sub 4} (1Zn, Cd) and M`V{sub 2}O{sub 6+{delta}} (0.5<{delta}<1; M` = Mn, Co). These oxides allows the low potential reversible insertion of lithium and can be used as negative electrodes in high performance lithium-ion batteries. (J.S.) 19 refs.

1996-12-31

399

Vacuum distillation refining and recycling of magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Purification parameters of the vacuum distillation process for AM50A and AZ31B magnesium alloy were studied. The vacuum distillation tests were kept at 580 C to 620 C up to 10 h under a vacuum pressure of about 1 Pa. The purification ratio for AM50A magnesium alloy increases with increasing the purification time. The chemical compositions of materials deposited purifying at 580 C for AM50A magnesium alloy almost satisfy the values for pure magnesium specified by JIS standard specification. The chemical compositions of deposited materials at 600 C for AZ31B magnesium alloy satisfy the values specified by the standard specification except for Zn. (orig.)

2003-07-01

400

Ultratrace determination in high purity molybdenum and tungsten with ion chromatographic trace-matrix-separation. Pt. 2; Ultra trace analysis using ion chromatography. Ultraspurenanalytik in hochreinem Molybdaen und Wolfram mit ionenchromatographischer Spuren-Matrix-Trennung. Tl. 2; Ionenchromatographische Ultraspurenanalyse  

Energy Technology Data Exchange (ETDEWEB)

The use of high-performance ion exchangers allows a trace-matrix-separation (SMT) directly followed by an ion chromatographic (IC) separation of the analytes. Based on the principles described in Part 1, a combined procedure IC-SMT-IC for metallic impurities in Mo and W is presented. Up to 12 metal traces (Fe, Cu, Pb, Zn, Ni, Co, Cd, Ca, Mn, Sr, Mg and Ba) can be determined in one run with 35 min. A special method for traces of U and Th is also given. Detection limits are typically 10-100 ng g{sup -1} in the metal sample. (author). 14 refs.; 10 figs.; 6 tabs.

1992-01-31

401

Theoretical study of the electronic structure of some cubic intermetallic compounds of dysprosium using the augmented plane wave method  

International Nuclear Information System (INIS)

The energy bands and the nature of the conduction electrons have been studied for three intermetallic compounds of dysprosium. e.g., DyZn, DyCu and DyRh, following the augmented plane wave method. Density of states results are given and have implications for the stability of the structure of the intermetallic compounds of dysprosium. The charge densities and the number of conduction electrons inside and outside the APW spheres in each of these compounds are calculated; it is shown that the character of conduction electrons within the Dy APW sphere is principally of d type for all the compounds. The consequence of the predominance of d electron in the conduction bands on the various physical parameters is discussed. (author).

402

The mechanism of uranium biosorption by Rhizopus arrhizus  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of elements is a little understood phenomenon exhibited by some types of even nonliving microbial biomass. A common fungus Rhizopus arrhizus has been reportd to take up uranium from adqueous solutions to the extent of 180 mg U/sup 6 +//g. The mechanism of uranium sequestering by this type of biomass was studied by using experimental techniques such as electron microscopy, x-ray energy dispersion analysis, IR spectroscopy, and supporting evidence was obtained for a biosorption mechanism consisting of at least three processes. Uranium coordination and adsorption in the cell-wall chitin structure occur simultaneously and rapidly whereas precipitation of uranylhdroxide within the chitin microcrystalline cell-wall structure takes place at a lower rate. Interference of Fe/sup 2/ and Zn/sup 2 +/ coions with uranium biosorption is indicated.

1982-02-01

403

The mechanism of thorium biosorption by Rhizopus arrhizus  

Energy Technology Data Exchange (ETDEWEB)

Inactive cells of Rhizopus arrhizus have been documented to exhibit a high thorium biosorptive uptake (170 mg/g) from aqueous solutions. The mechanism of thorium sequestering by this biomass type was investigated following the same method as for the uranium biosorption emchanism. The thorium sequestering mechanism appeared somewhat different from that of uranium. Experimental evidence is presented which indicates that, at optimum biosorption pH (4), thorium coordinates with the nitroge of the chitin cell wall network and, in addition, more thorium is adsorbed by the external section of the fungal cell wall. At pH 2 the overall thorium uptake is reduced. The kinetic study of thorium biosorption revealed a very rapid rate of uptake. Unlike uranium at optimum solution pH, Fe/sup 2 +/ and Zn/sup 2 +/ did not interfere significantly with the thorium biosorptive uptake capacity of R. arrhizus.

1982-04-01

404

The effect of trace elements on the fatigue behaviour of a carbide-hardened Fe-Ni-Cr alloy. Der Effekt von Spurenelementen auf das Zeitstandverhalten einer karbidverfestigten Fe-Ni-Cr-Legierung  

Energy Technology Data Exchange (ETDEWEB)

Fatigue tests were accomplished with a series of specimens doped with trace elements of a hardened Fe-Ni-Cr alloy, cast and hardened with intermetallic phases for determining the influence of these elements on the high temperature strength properties. The results of extensive fatigue tests show that even small contents of Te, Bi, Se, Pb, Tl and Zn considerably influence the life and creep processes especially after longer running periods, when added individually or combinedly. In contrast to this, the fatigue ductility is reduced by trace element additions even with short running periods. The order in which the metallic trace elements influence the fatigue properties nearly correlates with earlier work concerning Ni- and Co-superalloys. (orig.)

1993-01-01

405

The decay of a new nuclide: "7"1Br  

International Nuclear Information System (INIS)

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

1981-07-20

406

Synthesis of I-125 labeled photoaffinity rapamycin analogs  

International Nuclear Information System (INIS)

Two no-carrier-added "1"2"5I-labelled photoaffinity rapamycin analogs were prepared: 7-demethoxy-7-(4-azido-3-"1"2"5I-benzyloxy) rapamycin and its C_2_8-C_2_9 seco analog. The key reactions of the synthesis were substitution of the C_7 methoxyl of rapamycin with 4-azido-3-tributylstannylbenzyloxy group, exchange of tributyltin with "1"2"5I using Na"1"2"5I and Chloramine-T, and a ZnCl_2 mediated retro-Aldol cleavage of the C_2_8-C_2_9 bond of rapamycin. (author).

407

Synthesis and enhanced light absorption of alumina matrix nanocomposites containing multilayer oxide nanorods and silver nanoparticles  

British Library Electronic Table of Contents (United Kingdom)

In this paper, multilayer oxide nanorods were deposited in the nanopores of anodic aluminum oxide (AAO) via solution infiltration followed by heat treatment. The nanorods have a core-shell structure. First, the shell (nanotube) with the thickness of about 40nm was made of TiO"2 through the hydrolysis of (NH"4)"2TiF"6. Second, silver nanoparticles with the diameter of about 3nm were added into the TiO"2 layer through thermal decomposition of AgNO"3 at elevated temperatures. Then, cylindrical cores (nanorods) of CoO and ZnO with 200nm diameter were prepared, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the structure and composition of the nanorods. UV-vis light absorption measurements in the wavelength range from 350 to...

2011-01-01

408

Synchrotron SAXS Studies of Nanostructured Materials and Colloidal Solutions: A Review  

Scientific Electronic Library Online (English)

Abstract in english Structural characterisations using the SAXS technique in a number of nanoheterogeneous materials and liquid solutions are reviewed. The studied systems are protein (lysozyme)/water solutions, colloidal ZnO particles/water sols, nanoporous NiO-based xerogels, hybrid organic-inorganic siloxane-PEG and PPG nanocomposites and PbTe semiconductor nanocrystals embedded in a glass matrix. These investigations also focus on the transformations of time-varying structures and on str (more) uctural changes related to variations in temperature and composition. The reviewed investigations aim at explaining the unusual and often interesting properties of nanostructured materials and solutions. Most of the reported studies were carried out using the SAXS beamline at the National Synchrotron Light Laboratory (LNLS), Campinas, Brazil.

2002-03-01

409

Studies of interlayer magnetic coupling in all-semiconductor superlattices by means of neutron scattering techniques  

International Nuclear Information System (INIS)

An overview on neutron scattering studies of ferromagnetic and antiferromagnetic all-semiconductor superlattices is presented. Diffraction experiments on MnTe/CdTe, MnTe/ZnTe and EuTe/PbTe superlattices show pronounced correlations between the MnTe and EuTe layers across the non-magnetic spaces, even though these layers are antiferromagnetic and the systems are nearly-insulating. Current theory status of these systems is discussed. Diffractometry and reflectometry data from EuS/PbS superlattices reveal pronounced antiferromagnetic coupling between the ferromagnetic EuS block. First polarized neutron reflectometry data from superlattices prepared of a novel ferromagnetic 'spintronics' material, Ga(Mn)As are also presented. (author)

2001-09-23

410

Studies of crystalline CdZnTe radiation detectors and polycrystalline thin film CdTe for X-ray imaging applications  

CERN Document Server

The development of a replacement to the conventional film based X-ray imaging technique is required for many reasons. One possible route for this is the use of a large area film of a suitable semiconductor overlaid on an amorphous silicon readout array. A suitable semiconductor exists in cadmium telluride and its tertiary alloy cadmium zinc telluride. In this thesis the spectroscopic characteristics of commercially available CZT X- and gamma-radiation detectors are established. The electronic, optical, electro-optic, structural and compositional properties of these detectors are then investigated. The attained data is used to infer a greater understanding for the carrier transport in a CZT radiation detector following the interaction of a high energy photon. Following this a method used to fabricate large area films of CdTe on a commercial scale is described. This is cathodic electrodeposition from an aqueous electrolyte. The theory and experimental arrangement for this technique are ...

2001-01-01

411

Structure transformation and gain in properties of cast high-temperature T-6242 alloy by thermo-hydrogen treatment  

International Nuclear Information System (INIS)

Thermohydrogen treatment effect on microstructure and mechanical properties is studied for a cast heat resistant pseudo-#alpha#-titanium alloy Ti-6242 (Ti-6Al-2Sn-4Zn-2Mo) widely used as a heat resistant material with operating temperature up to 500 deg C. It is shown that reversible hydrogen alloying is a promising alternative to thermomechanical treatment for transformation of (#alpha#+#beta#)-titanium alloy structure. The application of thermohydrogen treatment is noted to be of particular efficiency for shaped casting technology as it allows a noticeable increase of mechanical properties at a lower cost. The alloy after thermohydrogen treatment and subsequent heat treatment in the (#alpha#+#beta#) - range possesses high values of yield strength fatigue properties, creep resistance and has a satisfactory ductility. A consideration is also given to thermohydrogen treatment effect on fatigue crack propagation and impact strength

412

Structure of Heavy Fe Nuclei at the Point of Transition at N #approx# 37  

International Nuclear Information System (INIS)

We have studied energy levels in "6"3Fe populated in the #beta#-decay of "6"3Mn. A new (preliminary) level scheme of "6"3Fe includes 10 excited states connected by 21 #gamma#-rays. The first excited states at 357 and 451 keV have the level half-lives of 110 ps and 780 ps, respectively. Three states, at 357, 451 and 1132 keV, are strongly #beta#-fed with log ft #approx# 5, while there is only a very week #beta#-feeding, if any at all, to the ground state. The new results imply that "6"3Fe departs from a simple shell model structure observed for heavier N = 37 isotones of "6"5Ni and "6"7Zn. (author)

2009-03-01

413

Strong coupled organic microcavities  

International Nuclear Information System (INIS)

Strong coupled organic-inorganic microcavities device has been realized and studied. One of the two cavities contains an organic thin film of tetrakis(4-methoxyphenyl)porphyrin, whereas the other microcavity is a dielectric structure coupled to the organic one by means of a LiF/ZnS Bragg mirror. Reflectivity spectra show the presence of two well defined cavity dips. We observe an energy splitting of the two cavity-modes. Despite only one cavity contains the active layer, the photoluminescence spectra display two peaks at the same energy of the reflectivity dips. These observations indicate the strong coupling of the two cavities. The comparison of the diagonalized effective Hamiltonian with the observed resonances further confirms the strong coupling.

2010-02-01

414

Status of nonsilicon photovoltaic solar cell research  

Energy Technology Data Exchange (ETDEWEB)

The current status of non-silicon photovoltaic solar cells is discussed including the identification of current technical and economic issues and future research directions for potential high efficiency low cost technologies. This review covers such advanced materials as CdS/Cu/sub 2/S, CdS/CuInSe/sub 2/, and GaAs homojunction and heterojunction devices; such emerging materials as InP, Zn/sub 3/P/sub 2/ and CdTe; and liquid junction electrochemical photovoltaic cells. An attempt is made to compare the current relative status of these various technologies and to indicate their near term potential where possible. 105 refs.

1980-01-01

415

Spectroscopy of neutron-rich {sup 59-63}Mn isotopes  

Science.gov (United States)

The neutron-rich Mn isotopes from A=59 to 63 have been studied through multi-nucleon transfer reactions by bombarding a {sup 238}U target with a beam of {sup 70}Zn at an energy of E{sub lab}=460 MeV. Prompt {gamma} rays measured by the CLARA array have been identified unambiguously for each nucleus, using coincidence relationships with ions detected in the high-acceptance magnetic spectrometer PRISMA. The new data extends the knowledge of the low-lying level structure of Mn isotopes, which is discussed in terms of the systematics of the region. Results are compared with large-scale shell-model calculations using different effective interactions and valence spaces.

2008-08-15

416

Spectroscopy of neutron-rich "5"9"-"6"3Mn isotopes  

International Nuclear Information System (INIS)

The neutron-rich Mn isotopes from A=59 to 63 have been studied through multi-nucleon transfer reactions by bombarding a "2"3"8U target with a beam of "7"0Zn at an energy of E_l_a_b=460 MeV. Prompt #gamma# rays measured by the CLARA array have been identified unambiguously for each nucleus, using coincidence relationships with ions detected in the high-acceptance magnetic spectrometer PRISMA. The new data extends the knowledge of the low-lying level structure of Mn isotopes, which is discussed in terms of the systematics of the region. Results are compared with large-scale shell-model calculations using different effective interactions and valence spaces.

2008-08-01

417

Solution state hybridization detection using time-resolved fluorescence anisotropy of quantum dot-DNA bioconjugates  

British Library Electronic Table of Contents (United Kingdom)

In this Letter, we demonstrate the application of time-resolved fluorescence anisotropy measurements to detect solution state hybridization of streptavidin conjugate (CdSe)ZnS quantum dots (QD). The study was performed on samples containing 10nM QD incubated with 800nM DNA. We show that the rotational correlation time of QD-DNA constructs increases significantly upon hybridization with values of 330ns (QD-ssDNA) and 1.3ms (QD-dsDNA), corresponding to a diameter of 14nm and 23nm respectively. The present study opens a new modality for hybridization detection using quantum dots.

2010-01-01

418

Rapid and cost-effective assessment of connectivity among assemblages of Choerodon rubescens (Labridae), using laser ablation ICP-MS of sagittal otoliths  

British Library Electronic Table of Contents (United Kingdom)

A rapid and cost-effective assessment was required to provide advice to management on the connectivity between juvenile and adult life cycle stages of Baldchin Groper Choerodon rubescens, a labrid endemic to the west coast of Australia, which has high social value, but relatively low commercial fishery importance. To minimise costs we used laser ablation ICP-MS to analyse levels of a small suite of elements (Ca, Mg, Mn, Cu, Zn, Sr, Rb, Ba and Pb) at the margin (adult phase) and core (juvenile phase) of the same otoliths of adult C. rubescens, collected at ten locations in five management zones. The elemental composition of both otolith margins and cores differed significantly among management zones and in some cases among locations within zones. Similarity of the pattern of among-zone elem...

2011-01-01

419

Raney-platinum film electrodes for potentially implantable glucose fuel cells. Part 1: Nickel-free glucose oxidation anodes  

British Library Electronic Table of Contents (United Kingdom)

We present a novel fabrication route yielding Raney-platinum film electrodes intended as glucose oxidation anodes for potentially implantable fuel cells. Fabrication roots on thermal alloying of an extractable metal with bulk platinum at 200^oC for 48h. In contrast to earlier works using carcinogenic nickel, we employ zinc as potentially biocompatible alloying partner. Microstructure analysis indicates that after removal of extractable zinc the porous Raney-platinum film (roughness factor ~2700) consists predominantly of the Pt3Zn phase. Release of zinc during electrode operation can be expected to have no significant effect on physiological normal levels in blood and serum, which promises good biocompatibility. In contrast to previous anodes based on hydrogel-bound catalyst particles the ...

2010-01-01

420

Radioactivity decontamination efficiency of ceramic filter in an incineration volume reduction system of radioactive waste  

Energy Technology Data Exchange (ETDEWEB)

The small pilot facility of a cyclone type suspension incineration system of radioactive waste was set up in order to evaluate the decontamination efficiency of a high efficiency ceramic filter. The evaluation was made by use of /sup 54/Mn, /sup 59/Fe, /sup 60/Co, /sup 65/Zn and /sup 137/Cs. 1. The decontamination factor by one line of ceramic filter for every species were over 10/sup 5/. 2. The decontamination factor increased by one oder when water vapor exists in off-gas. The same tendency was also observed when iron dioxide existed at the incineration of cation exchange resin.

1987-02-01

421

Radioactivity decontamination efficiency of ceramic filter in an incineration volume reduction system of radioactive waste  

International Nuclear Information System (INIS)

The small pilot facility of a cyclone type suspension incineration system of radioactive waste was set up in order to evaluate the decontamination efficiency of a high efficiency ceramic filter. The evaluation was made by use of "5"4Mn, "5"9Fe, "6"0Co, "6"5Zn and "1"3"7Cs. 1. The decontamination factor by one line of ceramic filter for every species were over 10"5. 2. The decontamination factor increased by one oder when water vapor exists in off-gas. The same tendency was also observed when iron dioxide existed at the incineration of cation exchange resin. (author).

422

Polymer-metal complex as gel electrolyte for quasi-solid-state dye-sensitized solar cells  

International Nuclear Information System (INIS)

A kind of polymer-metal complex gel electrolyte is successfully prepared and is used in dye-sensitized solar cells. Raman and X-ray photoelectron spectroscopy confirm the structure of this complex and is found that the metal ion reacts with nitrogen in the polymer. This novel electrolyte shows apparent diffusion coefficient of iodide of 8.37 x 10-7 cm2 s-1 and the energy conversion efficiency of 6.10% when the amount of ZnI2 is 0.04 M. By studying the dissociation active energy of the inorganic salt in electrolytes, we find that the metal salts can dissociate more easily after reacting with polymer and as a result can provide extra free iodide ion. The cell maintains ca. 93% of its initial efficiency after 20 d without further sealing, which shows good long-time stability.

2011-01-01

423

Optimized zinc electrode for the rechargeable zinc-air battery  

Energy Technology Data Exchange (ETDEWEB)

For the development of a long-lived, electrically rechargeable zinc-air battery the structure and wettability of pasted zinc electrodes were optimized. Pasted zinc electrodes containing 1 to 10% cellulose, but having almost the same nominal capacities, were prepared and tested in zinc/oxygen cells. The effect of discharge rate on cell voltage and delivered capacity, as well as the maximum power, were measured. Furthermore, cell charge-discharge behaviour and cycle life were examined. After different times of operation, the porosity and the pore size distribution of the pasted zinc electrodes were measured by means of mercury porosimetry. The life cycle and peak power drain capability of the Zn/oxygen battery could be substantially improved by the addition of 10 wt% cellulose to the pasted zinc electrode. (author)

1998-09-01

424

New highly active oxygen reduction electrode for PEM fuel cell and Zn/air battery applications (NORA). Final report  

Energy Technology Data Exchange (ETDEWEB)

This illustrated final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project concerning a new, highly active oxygen reduction electrode for PEM fuel cell and zinc/air battery applications. The goal of this project was, according to the authors, to increase the efficiency of the oxygen reduction reaction by lowering the activation polarisation through the right choice of catalyst and by lowering the concentration polarisation. In this work, carbon nanotubes are used as support material. The use of these nanotubes grown on perovskites is discussed. Theoretical considerations regarding activation polarisation are discussed and alternatives to the use of platinum are examined. The results of experiments carried out are presented in graphical and tabular form. The paper is completed with a comprehensive list of references.

2008-04-15

425

Neutron radiography with the cyclotron, 5. Cyclotron-based real time neutron fluoroscopy system and its application for some industrial components  

Energy Technology Data Exchange (ETDEWEB)

Reliable facility of cyclotron-based real time neutron radiography system has been developed and applied to some industrial components. The equipment for neutron fluoroscopy is based on a sub-compact cyclotron and a LiF/ZnS (Ag) fluorescent screen viewed by a silicon intensifier target TV camera. The real time image is monitored on a CRT, recorded with a standard video recorder and processed by a digital image processor. The effectiveness of our real time neutron radiograph has been demonstrated to be applicable to not only the dynamic observation but also the magnifying and stereoscopic observation of fluoroscopic images.

1987-03-01

426

Multielement analysis of air samples. Determination of iron, zinc, lead, and bromine content by the radionuclide X-ray fluorescence analysis  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide X-ray fluorescence analysis for nondestructive determination of Fe, Zn, Pb, and Br in air samples collected on nitrocellulose membrane filter Synpor 4 is described. A /sup 238/Pu source for the excitation and a semiconductor Si/Li detector for the detection of characteristic and L-fluorescent radiation of the above elements were used. A correction method based upon the measurements of simple or multiple Compton scattering for compensation of varying mass per unit area values in sample deposits was theoretically proposed and experimentally tested. The results obtained both with and without the correction were compared and good agreement with those given by atomic absorption spectrometry was observed.

1981-01-01

427

Measurement of induced radioactivity in materials found around a neutron generator  

Science.gov (United States)

The induced radioactivity in the construction materials of a Cockcroft-- Walton type neutron generator was measured. Major activation products (/sup 24/ Na, /sup 28/Al, /sup 56/Mn, /sup 64/Cu, /sup 65/Ni, /sup 69m/Zn, /sup 88/Rb /sup 91/Sr /sup 101/Mo, /sup 187/W/ and resulting doses are tabulated. Results show that the highest gamma activities would be observed in the fluorescent bulbs, copper pipe, aluminum lattice rod, and the aluminum pipe clamp. Thermoluminescent dosimeter readings yield the highest doses for the copper pipe tee, copper pipe, and aluminum lattice rod. Results of measuremerts of the neutron and gamma dose profiles of the facility are shown. However the indication is clearly that the tritium target, compared to other components, is the major source of radiation both during and after shutdown. (UK)

1974-01-01

428

Materials and processing designs for high-performance magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Materials and processing designs for advanced magnesium alloys with fine microstructures and superior properties were established by the combination of the repeated plastic working and the Mg{sub 2}Si synthesis in solid-state. The grain size was less than 1 {mu}m via RPW process due to its severe plastic working on raw powder. The hot extruded magnesium alloys produced in industries showed high ultimate tensile strength, e.g. 420{proportional_to}450 MPa, when employing Mg-Zn-Al-Ca-RE (Rare Earth) alloy coarse powder, having 0.5{proportional_to}2 mm diameter, as input materials. (orig.)

2005-07-01

429

Low-cycle fatigue behaviour and microstructure of copper and alpha-brass under biaxial load paths  

Energy Technology Data Exchange (ETDEWEB)

The low-cycle fatigue behaviour of copper and a-brass CuZn30 was investigated in uniaxial and biaxial tests. Planar biaxial fatigue tests were carried out using cruciform samples with proportional stain paths with and without phase shift between the two axes. Microcharacterisation was performed by electron microscopy as well as by high-resolution X-ray line profile analysis. The biaxial cyclic stress-strain curves show good agreement with the uniaxial ones using the von Mises equivalent strain hypothesis. The dislocation densities and microhardness values of the biaxial case, however, show significantly lower values compared to the uniaxial case at equivalent von Mises stresses.

2010-07-01

430

Lead, copper and zinc biosorption from bicomponent systems modelled by empirical Freundlich isotherm  

Energy Technology Data Exchange (ETDEWEB)

The biosorption of lead, copper and zinc ions on Rhizopus arrhizus has been studied for three single-component and two binary systems. The equilibrium data have been analysed using the Freundlich adsorption model. The characteristic parameters for the Freundlich adsorption model have been determined and the competition coefficients for the competitive biosorption of Pb(II)-Cu(II) at pH 4.0 and 5.0, and Pb(II)-Zn(II) at pH 5.0 have been calcualted. For the individual single-component isotherms, lead has the highest biosorption capacity followed by copper, then zinc. The capacity of lead in the two binary systems is always significantly greater than those of the other metal ions, in agreement with the single-component data. Only a partial selectivity for copper ions has been obtained at pH 4.0. (orig.)

2000-07-01

431

Laser surface modification for aqueous corrosion resistance  

International Nuclear Information System (INIS)

Laser surface modification can lead to formation of a novel microstructure on the surface of a material resulting in improved surface properties. During the past one and half decades, a number of investigations have been reported on laser surface modification techniques for improving the corrosion resistance of various materials. This paper reviews various work reported on utilising laser modification techniques for enhancing the aqueous corrosion resistance of materials. The laser surface modification work carried out on materials like stainless steels, C-steels, low alloy steels and non-ferrous materials such as Zr, Zn, Al, Ni, Mg and their alloys has been covered in the review. General features observed in improving the corrosion resistance after laser processing have been discussed and scope for future investigations in this field has been highlighted. (author). 97 refs., 15 figs., 5 tabs.

432

Large scintillation cells for high sensitivity radon concentration measurements  

Energy Technology Data Exchange (ETDEWEB)

Methods for improving the sensitivity of scintillation cells for radon concentration measurements were studied with emphasis on improving light collection efficiency. This allows the length and hence the volume of the cell to be increased. Variables studied were choice of scintillator material, its method of application and thickness, length of cell, cell material, type and configuration of reflectors, choice of photomultipliers, and factors affecting background. Response from various areas of the cell surface was studied with an alpha source and with radon filling. Coating the window with phosphor was found to be counter-productive. The optimum results obtained were with the inside of the cell (other than the window) covered with a thick layer of ZnS(Ag), or with a thick layer of reflective material coated with a thin layer of phosphor. With it, a 10 cm diameter plexiglass cell can be extended to at least 50 cm length without difficulty from insufficient pulse ...

1983-07-01

433

Large scintillation cells for high sensitivity radon concentration measurements  

International Nuclear Information System (INIS)

Methods for improving the sensitivity of scintillation cells for radon concentration measurements were studied with emphasis on improving light collection efficiency. This allows the length and hence the volume of the cell to be increased. Variables studied were choice of scintillator material, its method of application and thickness, length of cell, cell material, type and configuration of reflectors, choice of photomultipliers, and factors affecting background. Response from various areas of the cell surface was studied with an alphy source and with radon filling. Coating the window with phosphor was found to be counter-productive. The optimum results obtained were with the inside of the cell (other than the window) covered with a thick layer of ZnS(Ag), or with a thick layer of reflective material coated with a thin layer of phosphor. With it, a 10 cm diameter plexiglass cell can be extended to at least 50 cm length without difficulty from insufficient pulse ...

434

K-shell x-ray production cross sections of selected elements from Ti to Y for 0.5- to 2.5-MeV alpha-particle bombardment  

International Nuclear Information System (INIS)

K-shell x-ray production cross sections and K#beta#/K#alpha# ratios have been measured for thin targets of Ti, V, Cr, Fe, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, and Y for 0.5- to 2.5-MeV alpha particles. The experimental values are compared to the nonrelativistic plane-wave Born approximation (PWBA), the binary-encounter approximation, and the PWBA with binding energy and Coulomb deflection corrections. The PWBA with corrections provides the best agreement with the experimental cross sections.

435

Influence of annealing on the microstructure of commercial Mg alloy AZ31 after mechanical forming  

International Nuclear Information System (INIS)

The microstructure of commercial rolled magnesium alloy AZ31B (nominal composition Mg-3Al-0.9Zn-0.15Mn in wt.%) was investigated with the help of light microscopy, electron backscatter diffraction (EBSD) and X-ray diffraction technique after annealing in the temperature range from room temperature (RT) to 400 deg. C. Tensile tests at RT were performed to show the influence of the microstructure on mechanical properties. Static recrystallization (SRX) was observed during annealing of as-received alloy at and above 150 deg. C. Twins play an important role during SRX and serve as nucleation sites and preferred paths for growth of grains. The strong basal texture caused by rolling was weakened by SRX. Significant differences in the stress strain curves were observed for as-received and annealed specimens.

2006-09-25

436

Hydrogenation-defined stripe-geometry In sub 0. 5 (Al sub x Ga sub 1 minus x ) sub 0. 5 P quantum-well lasers  

Energy Technology Data Exchange (ETDEWEB)

Data are presented on the continuous-wave (cw), room-temperature (300 K) operation of stripe-geometry In{sub 0.5}(Al{sub {ital x}}Ga{sub 1{minus}{ital x}}){sub 0.5}P quantum-well heterostructure lasers defined via hydrogenation. Passivation of the Zn acceptors in the cap and upper confining layer provides gain guiding, and elimination of the current-blocking oxide reduces the thermal impedance. The resultant device is capable of better performance than conventional oxide-stripe diodes fabricated on the same material.

1990-12-01

437

Hydrogenation-defined stripe-geometry In sub 0. 5 (Al sub x Ga sub 1 minus x ) sub 0. 5 P quantum-well lasers  

Science.gov (United States)

Data are presented on the continuous-wave (cw), room-temperature (300 K) operation of stripe-geometry In{sub 0.5}(Al{sub {ital x}}Ga{sub 1{minus}{ital x}}){sub 0.5}P quantum-well heterostructure lasers defined via hydrogenation. Passivation of the Zn acceptors in the cap and upper confining layer provides gain guiding, and elimination of the current-blocking oxide reduces the thermal impedance. The resultant device is capable of better performance than conventional oxide-stripe diodes fabricated on the same material.

1990-12-01

438

Glycerol Hydrogenolysis over Co Catalysts Derived from a Layered Double Hydroxide Precursor  

British Library Electronic Table of Contents (United Kingdom)

Co catalysts, obtained from a layered double Co?Zn?Al hydroxide, are highly active and stable towards the hydrogenolysis of glycerol to 1,2-propanediol (1,2-PDO) in aqueous media. The Co-673 catalyst, containing a CoO species, provided a glycerol conversion of 67.7% and a 1,2-PDO selectivity of 50.5%. The Co-873 catalyst comprising 16?nm Co nanoparticles gave a glycerol conversion of 70.6% and a 1,2-PDO selectivity of 57.8%. It was revealed that the CoO species in the Co-673 catalyst was readily converted to 50?nm Co particles under the glycerol hydrogenolysis conditions. The Co catalysts maintained a stable size and phase in recycling tests. Graphical Abstract

2011-01-01

439

Furnace for rapid change of temperature for neutron diffraction  

International Nuclear Information System (INIS)

A new furnace for neutron diffraction experiments is capable of heating and cooling a sample very rapidly. The rapid heating is done by two circular infrared lamps placed over and under a sample, whose radiation is roughly focused on the sample by a reflector. The rapid cooling is done by high-pressure gas blows against the sample from two circular nozzles which are also placed over and under the sample. This system enables us to obtain the heating rate of over 1000"0C/min and cooling rate of -500"0C/min for an alloy of 10 mm diameter and 30 mm length. The performance is sufficient to carry out some kinetics measurements in real-time neutron diffraction by the use of a position-sensitive detector. This kind of experiment is demonstrated by the observation of the relaxation process of order--disorder transitions in CuZn and Ni_3Mn alloys.

440

Frequency upconversion properties of Ag: TeO2?ZnO nanocomposites codoped with Yb3+ and Tm3+ ions  

British Library Electronic Table of Contents (United Kingdom)

Yb3+?Tm3+ codoped tellurite glasses containing silver nanoparticles (NPs) were synthesized and characterized using transmission electron microscopy and optical techniques. The samples? composition and the nucleation of NPs were investigated using electron diffraction and energy dispersive spectroscopy. For the optical experiments, the samples were excited using a diode laser operating at 980?nm, in resonance with the Yb3+ transition 2F7/2?2F5/2. Photoluminescence (PL) bands corresponding to Tm3+ transitions were observed at 480, 650, and 800?nm due to the Yb3+? Tm3+ energy transfer. PL enhancement was achieved by heat-treatment of the samples at 325?C during different time intervals. The growth of the PL bands correlates with the increase of the silver NPs concentration. The relevant mecha...

2011-01-01

441

Flame retardancy of polybutylene terephthalate blended with various oxides  

British Library Electronic Table of Contents (United Kingdom)

The flame retardancy of polybutylene terephthalate (PBT) was studied focusing on the effect of various oxides. Thermo-gravimetric analysis, pyrolysis/gas chromatography/mass spectrometry, and elemental analysis (EA) were used to analyze the flame retardancy, which were observed through the UL-test and a cone calorimeter. Many oxides influenced the flame retardancy and some of them could suppress the flammability of PBT. In particular, the blended-PBTs with ZnO and V2O5 accelerated the degradation and the edges of oxygen consumption were shorter than neat-PBT although the flammability became poorer. The quantitative analysis of the scission products and the results of EA showed that hydrolysis, successive dehydration, and other various reactions changed the scission route to generate less f...

2008-01-01

442

Electrosynthesis of adherent poly(3-amino-1,2,4-triazole) films on brass prepared in nonaqueous solvents  

Energy Technology Data Exchange (ETDEWEB)

The kinetics of the electropolymerization of 3-amino-1,2,4-triazole on a brass substrate in alkaline solution containing methanol was investigated using cyclic polarization, chronoamperometry, electrochemical impedance techniques and scanning electronic microscopy. The polymeric film was prepared by successive cycles of potential of a 60Cu-Zn electrode between 0 and 1.6 V. During the second cycle, the oxidation peak of the monomer disappears indicating the formation of the insulating film. We have also shown that the monomer oxidation reaction is essentially irreversible and controlled by a diffusion process. The protective effect of the film formed on brass has been studied in a 3%NaCl and 3%NaCl + S{sup 2-} solution. The results showed important inhibition efficiency, about 96% for 4 h of testing time.

2008-06-15

443

Electrosynthesis of adherent poly(3-amino-1,2,4-triazole) films on brass prepared in nonaqueous solvents  

British Library Electronic Table of Contents (United Kingdom)

The kinetics of the electropolymerization of 3-amino-1,2,4-triazole on a brass substrate in alkaline solution containing methanol was investigated using cyclic polarization, chronoamperometry, electrochemical impedance techniques and scanning electronic microscopy. The polymeric film was prepared by successive cycles of potential of a 60Cu-Zn electrode between 0 and 1.6V. During the second cycle, the oxidation peak of the monomer disappears indicating the formation of the insulating film. We have also shown that the monomer oxidation reaction is essentially irreversible and controlled by a diffusion process. The protective effect of the film formed on brass has been studied in a 3%NaCl and 3%NaCl+S2- solution. The results showed important inhibition efficiency, about 96% for 4h of testing ...

2008-01-01

444

Elastic and inelastic scattering of "1"4C from medium heavy nuclei  

International Nuclear Information System (INIS)

The elastic and inelastic scattering of "1"4C at 51 MeV from targets of "4"0Ca, "5"6Fe, "6"0Ni, "6"6Zn and "8"8Sr has been measured using a Q3D spectrometer. The "1"4C-nucleus potentials have been derived by optical-model analysis of the observed elastic scattering; the inelastic scattering differential cross sections were interpreted in the distorted-wave Born approximation and also in the coupled-channels approach. The analysis yields "1"4C-nucleus potentials that closely resemble "1"2sup(,)"1"3C and "1"6O potentials. (orig.).

445

Development of process technology for large-area thin-film solar modules based on compound semiconductors. Final report; Entwicklung der technologischen Grundlagen fuer grosse Photovoltaikmodule auf Basis von Duennschicht-Verbindungshalbleitern. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

A cooperative effort of the Center for Solar Energy and Hydrogen Research (ZSW) and Phototronics Solartechnik GmbH (PST) aimed at the transfer of highly efficient solar cells developed on a laboratory scale, to large-area thin-film solar modules suitable for production. This work was based on research and development at the Institute for Physical Electronics (IPE) of Stuttgart University and ZSW on one hand, and on the know-how of PST in regard to large-area module fabrication on the other hand. The various thin-film layers of the cells and modules comprize molybdenum as rear contact, copper-indium(gallium)-diselenide (CIGS) as absorber material, the combination of cadmium sulphide (CdS) and ZnO as window layer. To produce these layers on large areas (30x30 cm{sup 2}), equipment was constructed and procedures were developed. Monolithic series connection of cells, used in other thin-film technologies, was studied and optimized by suitable patterning procedures, such ...

1998-06-01

446

Development of a small scintillation detector with an optical fiber for fast neutrons  

International Nuclear Information System (INIS)

To investigate the characteristics of a reactor and a neutron generator, a small scintillation detector with an optical fiber with ThO_2 has been developed to measure fast neutrons. However, experimental facilities where "2"3"2Th can be used are limited by regulations, and S/N ratio is low because the background counts of this detector are increase by alpha decay of "2"3"2Th. The purpose of this study is to develop a new optical fiber detector for measuring fast neutrons that does not use nuclear material such as "2"3"2Th. From the measured and calculated results, the new optical fiber detector which uses ZnS(Ag) as a converter material together with a scintillator have the highest detection efficiency among several developed detectors. It is applied for the measurement of reaction rates generated from fast neutrons; furthermore, the absolute detection efficiency of this detector was obtained experimentally.

2011-02-01

447

Determination of selected elements by radionuclide X-ray fluorescence analysis after the separation on different kinds of sorption materials  

International Nuclear Information System (INIS)

This paper aimed to the evaluation of different kinds of sorbent material preparation and to the evaluation of their characteristics at different pH conditions by X-ray fluorescence analysis. This method is suitable for identification and determination of elements in samples of different character, state and origin because it is a polycomponent, non-destructive, fast and simple analytical method. Moreover, it allows timeadvantageous and reliable measurements. This paper studies problems concerning the determination of some selected elements (Mn, Fe, Ni, Cu, Zn, Pb) in pharmaceutical samples of sodium chloride in the solid state as well as in its solution by sorption on chelating extraction membrane 3M Empore"T"M and on the strongly acidic ion-exchanger Dowex 50Wx8. Conditions for the most effective sorption of determined elements are also interpreted. (author)

2008-03-01

448

Determination of selected elements by radionuclide X-ray fluorescence analysis after the separation on different kinds of sorption materials  

British Library Electronic Table of Contents (United Kingdom)

This paper aimed to the evaluation of different kinds of sorbent material preparation and to the evaluation of their characteristics at different pH conditions by X-ray fluorescence analysis. This method is suitable for identification and determination of elements in samples of different character, state and origin because it is a polycomponent, non-destructive, fast and simple analytical method. Moreover, it allows time-advantageous and reliable measurements. This paper studies problems concerning the determination of some selected elements (Mn, Fe, Ni, Cu, Zn, Pb) in pharmaceutical samples of sodium chloride in the solid state as well as in its solution by sorption on chelating extraction membrane 3M Empore? and on the strongly acidic ion-exchanger Dowex 50Wx8. Conditions for the most ef...

2008-01-01

449

Determination of ratios of emission probabilities of Auger electrons and K-L-shell radiative vacancy transfer probabilities for 17 elements from Mn to Mo at 59.5keV  

Energy Technology Data Exchange (ETDEWEB)

The measurements of the K X-ray intensity ratio I(K{sub {beta}})/I(K{sub {alpha}}) for the 17 elements Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Y, Zr, Nb and Mo have been done following ionization by 59.5keV {gamma}-rays from a {sup 241}Am point source. Ratios of emission probabilities of Auger electrons and the vacancy transfer coefficients have been extracted in terms of the intensity ratios. It is found that the present results agree well with earlier fitted values and the semi-empirical values.

2006-01-15

450

Determination of macro, micro nutrient and trace element concentrations in Indian medicinal and vegetable leaves using instrumental neutron activation analysis  

Energy Technology Data Exchange (ETDEWEB)

Leafy samples often used as medicine in the Indian Ayurvedic system and vegetables were analyzed for 20 elements (As, Ba, Br, Ca, Ce, Cr, Cs, Co, Eu, Fe, K, La, Na, Rb, Sb, Sc, Sm, Sr, Th, Zn) by employing Instrumental Neutron Activation Analysis (INAA). The samples were irradiated at the 100 kW TRIGA-MAINZ nuclear reactor and the induced activities were counted by gamma ray spectrometry using an efficiency calibrated high resolution High Purity Germanium (HPGe) detector. The concentration of the elements in the medicinal and vegetable leaves and their biological effects on human beings are discussed.

1999-05-01

451

Comparison of methods used for preparation of biological CRM`s  

Energy Technology Data Exchange (ETDEWEB)

The starting material for two certified and one candidate reference material was obtained from dried grass specially cultivated on a selected and well prepared soil. The Community Bureau of Reference (BCR) of the Commission of the European Communities produced two certified reference materials (CRM`s) from this dried grass: a rye grass material (CRM 281) certified in 1988 for the quality control of trace and toxic element analyses and a hay powder material (CRM 129) certified in 1989 for monitoring trace and minor elements. A fraction of the dried grass was used in 1993 for the preparation of a hay powder with a particle size of < 63 {mu}m using newly developed grinding techniques. This paper compares the production methods of these three materials and the obtained particle size distribution of the powders. The analytical evaluation of these production methods was carried out by solid sampling Zeeman atomic absorption spectrometry for the determination of Cd, Pb and ...

1995-05-01

452

Availability of essential trace elements in Ayurvedic Indian medicinal herbs using instrumental neutron activation analysis  

Energy Technology Data Exchange (ETDEWEB)

Specific parts of several plants (fruits, leaves, stem, bark and roots) often used as medicines in the Indian Ayurvedic system have been analysed for 20 elements (As, Ba, Br, Ca, Cl, Co, Cr, Cu, Fe, K, Mn, Mo, Na, P, Rb, Sb, Sc, Se, Sr and Zn) by employing instrumental neutron activation analysis (INAA). The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted using high resolution gamma ray spectrometry. Most of the medicinal herbs have been found to be rich in one or more of the elements under study. (Author).

1997-01-01

453

Aspects of the carbon activated production since three Pinus species; Aspectos da producao de carvao ativado a partir de tres especies de pinus SPP  

Energy Technology Data Exchange (ETDEWEB)

Activated charcoal was produced from sawdust of Pinus caribaea var. caribaea, pinus caribaea var. honduenais and pinus cocarpa, with the objective of studying a alternative of more economic uses for forest residues and the products of the first thinning. A chemical process was utilized based on Zn Cl{sub 2} at temperature of 700 deg C and 450 deg C. It was concluded that the temperature of 700 Celsius produced a activated charcoal with better quality and greater adsorption capacity. The temperature of 450 deg C produced a material with adsorption properties for utilization where greater adsorption capacity is not needed. The production of activated charcoal is possible from the three species of tropical pinus studied. (author). 16 refs., 5 tabs

1987-12-31

454

A new zinc hydroxide nitrate heterogeneous catalyst for the esterification of free fatty acids and the transesterification of vegetable oils  

British Library Electronic Table of Contents (United Kingdom)

A new heterogeneous catalyst for the esterification of free fatty acids and the transesterification of vegetable oils is reported. The layered compound zinc hydroxide nitrate (Zn5(OH)8(NO3)22H2O) was very effective in the alcoholysis of palm oil and the esterification of lauric acid with m(ethanol), even when hydrated ethanol was used. Over the range of 100-140degreeC, the ester yield was the highest at 140degreeC, while the catalyst concentration had a much greater effect on ester yields than the molar ratio of alcohol to acid did. Total ester contents above 95wt% were obtained in both reactions and 93.2wt% glycerin streams were recovered as a result of methanolysis.

2008-01-01

455

A 1500-year record of lead, copper, arsenic, cadmium, zinc level in Antarctic seal hairs and sediments  

British Library Electronic Table of Contents (United Kingdom)

To reconstruct the profiles of heavy metal levels in the South Ocean ecosystem of Antarctica, the concentrations of lead (Pb), copper (Cu), arsenic (As), cadmium (Cd), and zinc (Zn) in seal hairs and lake sediments spanning the past 1500?years from Fildes Peninsula of King George Island and in weathering lake sediments from Nelson Island of West Antarctica were determined. The lead contents in the seal hairs and the weathering sediments show a sharp increase since the late 1800s, very likely due to anthropogenic contamination from modern industries. After the 1980s, the Pb content in seal hairs dropped by one-third, apparently due to the reduced usage of leaded gasoline in the Southern Hemisphere. Copper arises mainly from the weathering process, and its level may be substantially affected...

2006-01-01

456

The relationship between seminal plasma zinc levels and high molecular weight zinc binding protein and sperm motility in Iraqi infertile men  

International Nuclear Information System (INIS)

To evaluate the relationship between sperm motility and total seminal plasma zinc concentration and high molecular weight zinc bound protein values in infertile Iraqi men. A case-control study was conducted at the Chemistry and Biochemistry Department, College of Medicine, Al-Nahrain University, Baghdad, Iraq between March 2005 to February 2006. The subjects for the study included 60 infertile male patients who were recruited Al-Kadhimiya Teaching Hospital, and Institute of Embryo Research and Infertility Treatment, Baghdad, Iraq. They were categorized according to their seminal parameters to oligozoospermia (n=32), azoospermia (n=22), and asthenozoospermia (n=6). Thirty nine fertile men (age range 31.87 +/- 3.76 years) were selected as controls, whose partners had conceived within the last year before participation with this study, and having normal spermiogram parameters. Seminal plasma zinc concentration and high molecular weight zinc binding proteins (HMW-Zn) ...

457

Synthesis, crystal structure, spectroscopic and photoluminescence studies of manganese(II), cobalt(II), cadmium(II), zinc(II) and copper(II) complexes with a pyrazole derived Schiff base ligand  

British Library Electronic Table of Contents (United Kingdom)

Varying coordination modes of the Schiff base ligand H"2L [5-methyl-1-H-pyrazole-3-carboxylic acid (1-pyridin-2-yl-ethylidene)-hydrazide] towards different metal centers are reported with the syntheses and characterization of four mononuclear Mn(II), Co(II), Cd(II) and Zn(II) complexes, [Mn(H"2L)(H"2O)"2](ClO"4)"2(MeOH) (1), [Co(H"2L)(NCS)"2] (2), [Cd(H"2L)(H"2O)"2](ClO"4)"2 (3) and [Zn(H"2L)(H"2O)"2](ClO"4)"2 (4), and a binuclear Cu(II) complex, [Cu"2(L)"2](ClO"4)"2 (5). In the complexes 1-4 the neutral ligand serves as a 3N,2O donor where the pyridine ring N, two azomethine N and two carbohydrazine oxygen atoms are coordinatively active, leaving the pyrazole-N atoms inactive. In the case of complex 5, each ligand molecule behaves as a 4N,O donor utilizing the pyridine N, one azomethine N...

2011-01-01

458

Synthesis of c-axis preferred orientation ZnO:Al transparent conductive thin films using a novel solvent method  

International Nuclear Information System (INIS)

Transparent aluminum doped zinc oxide (ZnO:Al, AZO) conducting thin films with a high-preferential c-axis orientation were synthesized using a new sol-gel formula. The films were deposited using a spin-coating route onto borosilicate glass substrates. We used propylene glycol methyl ether (PGME) as the solvent in place of ethylene glycol monomethyl ether (EGME), which is commonly used because it is easier to deposit onto the substrates. PGME is also superior in terms of health and safety. PGME solvent does not need to settle for several days before use and can be spin-coated as soon as the raw material and solvent are mixed. The effects of this novel solvent on the structural, morphological, electrical and optical properties are discussed using XRD, SEM, a four-point probe and UV-VIS spectrophotometry. It was found that the films produced with PGME showed a high-preferential c-axis orientation and compact microstructure in comparison films produced using EGME. The ...

2010-09-01

459

Simultaneous estimation of trace and toxic metals through drinking water from Tarapur using ICP-AES  

International Nuclear Information System (INIS)

In the present paper the contamination levels of trace and toxic metals in drinking water collected from Tarapur industrial area, Thane were investigated. The concentrations of trace and toxic metals (Pb, Cd, Cu, Cr, Ni, Se, V, Zn, Mn, Mo, Co, As and Ba) were determined simultaneously using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The results were compared with international water quality guidelines (WHO, 2008) and were found within the permissible limits. The quality assurance was checked by standard addition method and spike recovery. The concentration of Pb, Cd, Cu, Cr, Ni, Se, V, Zn, Mn, Mo, Co, As and Ba varies from 4.25-19.62 #mu#g/L, 0.13-1.49 #mu#g/L, 0.60-65.55 #mu#g/L, 0.46-4.15 #mu#g/L, <0.1 #mu#g/L, 0.5- 9.35 #mu#g/L, <0.5 #mu#g/L, 3.41-99.64 #mu#g/L, 0.80-9.62 #mu#g/L, 0.30-1.48 #mu#g/L, <0.1-0.90 #mu#g/L, <0.63 #mu#g/L and 0.71-9.0 #mu#g/L respectively. Similarly Na, K, Ca and Mg varies from ...

2010-05-13

460

Layered GdBa_0_._5Sr_0_._5Co_2O_5_+_#delta# as a cathode for proton-conducting solid oxide fuel cells with stable BaCe_0_._5Zr_0_._3Y_0_._1_6Zn_0_._0_4O_3_-_#delta# electrolyte  

International Nuclear Information System (INIS)

The layered GdBa_0_._5Sr_0_._5Co_2O_5_+_#delta# (GBSC) perovskite oxides are synthesized by modified Pechini method and investigated as a novel cathode material for solid oxide fuel cells (SOFCs) based on a stable perovskite oxide BaCe_0_._5Zr_0_._3Y_0_._1_6Zn_0_._0_4O_3_-_#delta# (BCZYZ) as electrolyte. The fabricated single cells of NiO-BCZYZ/BCZYZ (#approx#20 #mu#m)/GBSC (#approx#20 #mu#m) were operated from 550 to 700 "oC with humidified hydrogen (#approx#5% H_2O) as fuel. The BCZYZ perovskite electrolyte was completely dense after sintered at 1250 "oC for 5 h, lower than that without zinc dopant about 150 "oC. An open circuit voltage of 1.009 V and a maximal power density of 0.35 W cm"-"2 were achieved at 700 "oC. The interfacial polarization resistance was as low as 1.46, 0.45, 0.25 and 0.15 #OMEGA# cm"2 at 550, 600, 650 and 700 "oC, respectively. The ratio of polarization resistance to total cell resistance decreased with the increase in the operating ...

2010-04-30

461

Interaction between high levels of applied heavy metals and indigenous soil manganese  

Energy Technology Data Exchange (ETDEWEB)

The importance of indigenous soil Mn level on plant Mn uptake from metal salt or sewage sludge amended soils was investigated. Twelve soil materials, six surface and six subsurface, were amended with either varying rates of a composite of Cd, Cu, Ni, and Zn sulfate salts, equivalent to the total of these metals present in a digested sewage sludge (Washington, DC) at rates of 0 to 896 dry metric tons/ha or with the sludge itself, at 224 dry metric tons/ha. Corn (Zea mays L.) was grown in the greenhouse for 30 days, 1 year after amendment application. Two pH levels of about 5.5 and 6.5 were maintained during the experiment on the metal salt amended soil materials. Plant tissue Mn levels increased with the application of Cd, Cu, Ni, and Zn (in combination) as metal salts or as sewage sludge over the range of soil materials used. The amount of increase with a given increase in applied metals was greater for the unlimed than for the limed metal salt ...

1981-01-01

462

Inorganic profile of some Brazilian medicinal plants obtained from ethanolic extract and ''in natura'' samples  

Energy Technology Data Exchange (ETDEWEB)

The Anadenathera macrocarpa, Schinus molle, Hymenaea courbaril, Cariniana legalis, Solidago microglossa and Stryphnodendron barbatiman, were collected ''in natura'' samples (leaves, flowers, barks and seeds) from different commercial suppliers. The pharmaco-active compounds in ethanolic extracts had been made by the Mato Grosso Federal University (UFMT). The energy-dispersive x-ray fluorescence (ED-XRF) spectrometry was used for the elemental analysis in different parts of the plants and respective ethanolic extracts. The Ca, Cl, Cu, Fe, K, Mg, Mn, Na, Ni, P, Rb, S, Sr and Zn concentrations were determined by the fundamental parameters method. Some specimens showed a similar inorganic profile for ''in natura'' and ethanolic extract samples and some ones showed a distinct inorganic profile. For example, the Anadenathera macrocarpa showed a similar concentration in Mg, P, Cu, ...

2004-10-03

463

Effects of inorganic cation templates on octahedral molecular sieves of manganese oxide  

Science.gov (United States)

Five hydrated inorganic divalent cations, Mg[sup 2+], Co[sup 2+], Ni[sup 2+], Cu[sup 2+], and Zn[sup 2+], have successfully been used as templates for the synthesis of manganese oxide octahedral molecular sieves (OMS-1) having the todorokite structure. The OMS-1 samples have been well characterized by X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy/energy dispersive X-ray studies, inductively coupled plasma analysis, electron paramagnetic resonance, Fourier transform infrared spectroscopy, thiosulfate titration, and cyclohexane sorption. Catalytic CO oxidation and 2-propanol decomposition were carried out. Results show that these OMS-1 samples with a tunnel size of about 6.9 angstroms are crystalline and chemically pure. They have the following formulas: Mg[sub 3.17]Mn[sub 5.05]O[sub 12] [center dot] 4.52H[sub 2]O, Co[sub 1.84]Mn[sub 5.59]O[sub 12] [center dot] 3.45H[sub 2]O, Ni[sub 1.64]Mn[sub ...

1994-11-30

464

Effect of various coal contaminants on the performance of solid oxide fuel cells: Part I. Accelerated testing  

Energy Technology Data Exchange (ETDEWEB)

The contaminants that are potentially present in the coal-derived gas stream and their thermochemical nature are discussed. Accelerated testing was carried out on Ni-YSZ/YSZ/LSM solid oxide fuel cells (YSZ: yttria stabilized zirconia and LSM: lanthanum strontium manganese oxide) for eight main kind of contaminants: CH{sub 3}Cl, HCl, As, P, Zn, Hg, Cd and Sb at the temperature range of 750-850 C. The As and P species, at 10 and 35 ppm, respectively, resulted in severe power density degradation at temperatures 800 C and below. SEM and EDX analysis indicated that As attacked the Ni region of the anode surface and the Ni current collector, caused the break of the current collector and the eventual cell failure at 800 C. The phosphorous containing species were found in the bulk of the anode, they were segregated and formed ''grain boundary'' like phases separating large Ni patches. These species are presumably nickel ...

2009-09-05

465

Effect of soil amendments and crop varieties on the amelioration of heavy metal uptake into crops grown on polluted soils of Bangladesh  

International Nuclear Information System (INIS)

Bangladesh possesses many industrial sites, whereby wastes and effluents are directly discharged into the environment without any treatment. Agricultural areas are contaminated thereby and the food quality is impaired. Therefore, the aim of the present work was to develop simple and cost effective strategies to reduce soil-plant transfer of harmful substances. Three sites were selected in the vicinity of Dhaka city (Tongi pharmaceutical, Tejgaon industrial and Hazaribagh tannery area). Field and pot experiments were carried out with different varieties of field crops (rice, wheat and tomato) and different soil amendments (cowdung, city waste compost, oil cake, waterhyacinth, poultry litter, lime and red mud). At the site Tongi, pollutants mainly consists of organic compounds. The soil of Tejgaon is acidic (pH=5.7), contains high organic matter and elevated concentrations of Zn (685 mg/kg), Pb (136 mg/kg), and Cd (2.6 mg/kg). The Hazaribagh region is polluted by a ...

466

Determination of trace amounts of cadmium, cobalt, chromium, iron, molybdenum, nickel, selenium, titanium, vanadium and zinc in blood and milk by neutron activation analysis  

International Nuclear Information System (INIS)

The concentrations of Cd, Co, Cr, Fe, Mo, Ni, Se, Ti, V and Zn in biological fluids, human blood serum and market milk were determined by neutron activation analysis, with enrichment by coprecipitation. The pre-concentration of these trace elements was accomplished by converting the dissolved trace metal ions into their pyrrolidinedithiocarbamate (1-pyrrolidinecarbodithioate) chelates, followed by coprecipitation with a metal carrier such as Ni, Pb or Bi. The coprecipitation was carried out prior to irradiation for the short-lived nuclides (V, Ti and Se) and after irradiation for the other elements. The validity of the method was checked using certified biological reference materials; the concentrations of trace elements found by the proposed method agreed well with the published certified data. The limits of detection for Cd, Co, Cr, Fe, Mo, Ni, Se (obtained through the long-lived isotope "7"5Se) and Zn under the present experimental ...

467

Corrosion fatigue of magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

To study the fatigue life of extruded AZ31 (3%Al, 1%Zn, 0.3%Mn, Mg - the rest), AM50 (5%Al, 0.4%Mn, Mg - the rest) and ZK60 (5%Zn, 0.5%Zr, Mg - the rest) Mg alloys in air and NaCl-based solutions, corrosion fatigue tests were carried out using a rotating beam type fatigue machine. For the analysis of the corrosion fatigue behavior of Mg alloys in different environments, fitted N{sub sol}/N{sub air} ratio considered as a relative corrosion fatigue life is used. Here N{sub sol} and N{sub air} are the numbers of cycles to failure in the solution and in air, respectively. An extruded ZK60 alloy shows very high fatigue and corrosion fatigue properties in comparison with other alloys. However, ZK60 shows the lowest values of the relative fatigue life (N{sub sol}/N{sub air} {proportional_to}10{sup -3}-10{sup -2}) compared to that for AM50 and AZ31 alloys (N{sub sol}/N{sub air} {proportional_to}10{sup -2} - 10{sup -1}). Generally, extruded alloys in ...

2003-07-01

468

Application of neutron activation analysis method in leaves of Casearia obliqua medicinal plant; Aplicacao do metodo de analise por ativacao com neutrons na analise de folhas da planta medicinal Casearia obliqua  

Energy Technology Data Exchange (ETDEWEB)

The pharmacological properties of medicinal plants have been related to the presence of organic compounds, however elements are also known to have an important participation in the active compounds constitution process. In this study, instrumental neutron activation analysis (INAA) was applied to determine elements in leaves of Casearia obliqua medicinal plant collected at two different locations in the Atlantic Forest, Brazil, SP. Soil samples collected from where this plant was grown were also analyzed in order to verify if there is a correlation between the elements present in soils and plant leaves. Br, Ca, Cl, Co, Cr, Cs, Fe, K, La, Mn, Na, Rb, Sb, Sc and Zn were determined in C. obliqua leaves and the elements As, Ca, Ce, Eu, Fe, Hf, La, Lu, Nd, Rb, Sc, Sm, Tb, Th, U and Zn in soils. Soil samples collected from two different locations presented similar concentrations for most elements. Likewise, C. obliqua leaves collected from the two ...

2005-07-01

469

Affinity dialysis - a method of continuous, rapid metal ion separation using dialysis membranes and selective, water-soluble polymers as extractants  

Energy Technology Data Exchange (ETDEWEB)

A membrane process utilizing dialysis and selective complexation by water-soluble polymers has been developed. This process, termed affinity dialysis, has been shown to be selectively extract and concentrate both cations and anions in a manner similar to ion exchange or solvent extraction. The selective removal of calcium from sodium with selectivity of about 30, removal of chromate ion from dilute streams, and separation of transition metal ions such as Cu/Fe and Cu/Zn have all been successfully demonstrated. Effects of different polymers, polymer concentration, temperature, and flow rates have been studied. The effect of increased polymer concentration is to increase product concentration if appropriate changes in feed, polymer solution, and strip flow rates are made. A continuous polymer solution recycle and regeneration system has been constructed and operated with Cu/Zn and chromate/chloride feed streams. Removal of over 95% of the desired ...

1988-08-01

470

Activation analysis of trace elements in titanium-molybdate target used for pre-formed TiMo gel based "9"9"mTc generator production and radionuclidic impurity of "9"9"mTc pertechnetate eluate  

International Nuclear Information System (INIS)

A gel-type "9"9Mo-"9"9"mTc generator using Titanium-Molybdate target (TiMo-target) as column packing was developed in Radioisotope Department, the Dalat Nuclear Research Institute [1]. The concentration of trace elements in TiMo-target and radionuclidic purity in "9"9"mTc solution eluted from this type of generator were studied for quality control purpose. The monostandard method in neutron activation analysis has been applied to determine the concentration of trace impurities in titanium-molybdate target. For neutron activation analysis, TiMo samples were irradiated in the different channels of nuclear reactor IVV-9 at a neutron flux of maximum 2.1 x 10"1"3 n.cm"-"2s"-"1. The following chemical element impurities were determined: Na, W, Co, Fe, Zn, Ag, Sb and Cr. The gamma ray emitted nuclides found in "9"9"mTc solution eluted from our "9"9"mTc generator were the following: "6"5Zn, "6"0Co, "1"1"0"mAg, "5"9Fe, "5"1Cr, "2"4Na, "8"2Br and "9"9Mo. ...

2004-06-01

471

GRAIN REFINEMENT OF PERMANENT MOLD CAST COPPER BASE ALLOYS  

Energy Technology Data Exchange (ETDEWEB)

Grain refinement behavior of copper alloys cast in permanent molds was investigated. This is one of the least studied subjects in copper alloy castings. Grain refinement is not widely practiced for leaded copper alloys cast in sand molds. Aluminum bronzes and high strength yellow brasses, cast in sand and permanent molds, were usually fine grained due to the presence of more than 2% iron. Grain refinement of the most common permanent mold casting alloys, leaded yellow brass and its lead-free replacement EnviroBrass III, is not universally accepted due to the perceived problem of hard spots in finished castings and for the same reason these alloys contain very low amounts of iron. The yellow brasses and Cu-Si alloys are gaining popularity in North America due to their low lead content and amenability for permanent mold casting. These alloys are prone to hot tearing in permanent mold casting. Grain refinement is one of the solutions for reducing this problem. However, to use this ...

2004-04-29

472

Trap-nests used by Centris (Heterocentris) terminata Smith (Hymenoptera: Apidae, Centridini) at secondary Atlantic Forest fragments, in Salvador, Bahia State; Ninhos de Centris (Heterocentris) terminata Smith (Hymenoptera: Apidae, Centridini) em fragmentos de Mata Atlantica secundaria, Salvador, BA  

Energy Technology Data Exchange (ETDEWEB)

Ninety-five nests of Centris (Heterocentris) terminata Smith were collected in trap nests, during November/2001 and January/2003, at two fragments (PZGV e CFO-UFBA) of secondary Atlantic Forest, in Salvador, Bahia State (13 deg 01' W and 38 deg 30' S). The highest nest frequencies occurred from December to February (summer), with no nests foundations from August to October (winter - early spring). Two-hundred eight adults emerged from 347 brood cells, being 164 males and 116 females (1: 0.42). During the study period sex ratio was male biased ({chi}{sup 2} = 9.342; gl = 10; P < 0.05). C. terminata nested in holes with diameters 6, 8, 10 mm, but 84,2% were constructed in 8 and 10 mm. nests had one to seven cells arranged in a linear series with the cell's partitions built with a mixture of sand and resin or oil. Male is significantly smaller than female, which emerges from the first cells constructed. Immature mortality occurred in 14.1% of brood cells ...

2008-05-15

473

The interaction of /sup 125/I-insulin with cultured 3T3-L1 adipocytes: quantitative analysis by the hypothetical grain method  

Energy Technology Data Exchange (ETDEWEB)

The murine 3T3-L1 fibroblast under appropriate incubation conditions differentiates into an adipocyte phenotype. This 3T3-L1 adipocyte exhibits many of the morphologic, biochemical, and insulin-responsive features of the normal rodent adipocyte. Using quantitative electron microscopic (EM) autoradiography we find that, when /sup 125/I-insulin is incubated with 3T3-L1 adipocytes, the ligand at early times of incubation localizes to the plasma membrane of the cell preferentially to microvilli and coated pits. When the incubation is continued at 37 degrees C, /sup 125/I-insulin is internalized by the cells and preferential binding to the villous surface is lost. With the internalization of the ligand, two intracellular structures become labeled, as determined by the method of hypothetical grain analysis. These include large clear, presumably endocytotic, vesicles and multivesicular bodies. Over the first hour of incubation the labeling of these structures increases in ...

1983-07-01

474

Soybean biodiesel consumption in agricultural tractor submitted the two forces in the traction bar; Consumo de biodiesel de soja em trator agricola submetido a duas forcas na barra de tracao  

Energy Technology Data Exchange (ETDEWEB)

Due to the great development occurred in the world after the Second World War and the establishment of patterns of increasingly intense, the energy demand amounted to the point, putting at risk the non-renewable energy sources such as oil, coal minerals, among others, with growing interest in renewable energies, among which the biodiesel has been detached. In this sense, the present work had for objective to evaluate the fuel consumption of a tractor Valtra BM100 4x2 TDA, running with ethyl biodiesel from soybean filtered in seven mixture proportions mixed with the diesel, subject to two forces in the traction bar. The work was conducted in the Department of Rural Engineering of the Paulista State University (UNESP), Jaboticabal Campus, in an entirely randomized designed, in a factorial diagram 2 x 7, with three repetitions. The treatments were a combination for two forces in the traction bar (10 and 22 kN) and seven mixture proportions (B{sub 0}, B{sub 5}, B{sub 1}5, B{sub 2}5, B{sub ...

2009-07-01

475

Seasonal variations in photosynthetic response of algae epiphytic on Myriophyllum spicatum L  

Energy Technology Data Exchange (ETDEWEB)

The photosynthetic response to light of epiphytic algae from Lake Wingra, Wisconsin was determined monthly during the 1978 and 1979 growing seasons.A /sup 14/C technique was developed for measurement of photosynthesis of the intact epiphyte community which was then removed by shaking. The photosynthetic rate at low light, ..cap alpha.., varied from 5.56 to 18.26 ..mu..g C (mg Chl a)/sup -1/ h/sup -1/ (..mu..Em/sup -2/s/sup -1/)/sup -1/ while P/sup B//sub max/, the photosynthetic rate at light saturation, ranged from 1.0 to 2.6 mg C (mg Chl a)/sup -1/ h/sup -1/. During 1979, variations in ..cap alpha.. and P/sup B//sub max/ followed the sun-shade model for photosynthetic adaptation: P/sup B//sub max/ was highest in summer and lowest in spring and fall, while ..cap alpha.. followed the opposite pattern. Patterns in ..cap alpha.. and P/sup B//sub max/ for 1978 were less apparent. During 1979, P/sup B//sub max/ was significantly correlated with both temperature and ...

1982-07-01

476

SUPPLEMENTAL COLUMBIA RIVER PROTECTION ACTIVITIES AT THE DEPARTMENT OF ENERGY HANFORD SITE: 2006 TECHNICAL PEER REVIEW  

Energy Technology Data Exchange (ETDEWEB)

Prompted by a $10 million Congressional allocation to identify supplemental actions to protect the Columbia River from groundwater contamination beneath the Hanford Reservation, the U. S. Department of Energy (DOE) Environmental Management (EM) Office of Clean-up Technology identified twenty-three potential technical projects and then down-selected ten of these for further evaluation. An independent expert peer review was conducted for the ten down-selected proposals. The review panel consisted of twenty-three recognized subject matter experts that broadly represented academia, industry, and federal laboratories. Of the initial ten proposals reviewed, one was given unconditional support, six were given conditional support, and three were not supported as proposed. Three additional proposals were then submitted by DOE for review--these proposals were structured, in part, to respond to the initial round of technical peer review comments. Peer reviews of these ...

2006-12-20

477

Real-time neutron radiography; Radiografia com neutrons em tempo-real  

Energy Technology Data Exchange (ETDEWEB)

The main objective of the present thesis was develop and get operational a real-time neutron radiography system, at the IPEN-CNEN/SP. This system is installed inside the shielding of an old facility, designed in 1988, for film radiography, which is installed at the beam-hole 08 of the 5 MW, IEA-R1 Nuclear Research Reactor. The most important modifications at the such facility were the increase of the {gamma}-radiation filter thickness, increase of the inner area of the shielding, design of a neutron collimator and a light tight box. The main characteristics of the neutron beam at the irradiation position are: flux: 1 x 10{sup 6}n/cm{sup 2}s, collimation ratio 70, effective energy 7 meV, diameter 20 cm, neutron/{gamma} ratio {approx} 10{sup 6}n/cm{sup 2}mrem. The real-time images have been obtained by means of an imaging system that consists of a screen scintillator, a light intensifier, a video camera, a digitizing frame grabber and a computer. The device composed by the scintillator ...

2000-07-01

478

Occupational exposure prevention program to oil and gas industry; Antecipacao, reconhecimento, avaliacao e controle dos riscos ambientais em uma planta de petroleo e gas  

Energy Technology Data Exchange (ETDEWEB)

PETROBRAS/TRANSPETRO Pipelines and Terminals have 500 regular employees and 5.064 out sourced workers in its Southeast Division. The out sourced employees work under 125 contracts involving a wide range of activities such as maintenance, pipeline operation, pipeline launching, engineering, administrative and auxiliary services. Among these workers, 1.200 peoples are subjected to occupational exposure, which may be present in the industrial process or in the products transported in our pipelines, e.g. industrial noise, sulfidric gas, toluene, xylene and benzene (recognized as a carcinogen according to ACGIH and Brazilian Ministry of Labour). Our PPRA (acronym in Portuguese for Occupational Exposure Prevention Program) involves the workforce and fosters health by anticipation, recognition, evaluation and control of the situations that may result in injuries. Further actions include the procurement of equipment for detection of these agents not only in the air but also diluted in liquids ...

2005-07-01

479

Luminescent platinum(II) complexes of quinoxaline-2,3-dithiolate  

Energy Technology Data Exchange (ETDEWEB)

The synthesis, characterization, and photophysical properties of several Pt(II) complexes of quinoxaline-2,3-dithiolate (qdt) and 6,7-dimethylquinoxaline-2,3-dithiolate (dmqdt) are described. Specifically, (TBA){sub 2}[Pt(qdt){sub 2}], where TBA = tetra-n-butylammonium, Pt(COD)(qdt), where COD = 1,5-cyclooctadiene, and Pt(phen)(qdt), where phen = 1,10-phenanthroline, and their dmqdt analogs have been prepared and examined with respect to their photophysical properties. Highly structured emission from Pt(COD)(qdt) in frozen glass solution at 77 K has been detected, having a major vibrational progression of 1370 cm{sup {minus}1} corresponding to a C=C stretching frequency of the quinoxalinedithiolate backbone. Solution luminescence from (TBA){sub 2}[Pt(qdt){sub 2}] and Pt(phen)(qdt) has been detected with quantum yields, {Phi}{sub em}, of 10{sup {minus}5} and 10{sup {minus}3}, respectively, although the latter is highly sensitive to solvent effects. The complex ...

1995-04-12

480

Gas Storage Technology Consortium  

Energy Technology Data Exchange (ETDEWEB)

The EMS Energy Institute at The Pennsylvania State University (Penn State) has managed the Gas Storage Technology Consortium (GSTC) since its inception in 2003. The GSTC infrastructure provided a means to accomplish industry-driven research and development designed to enhance the operational flexibility and deliverability of the nation's gas storage system, and provide a cost-effective, safe, and reliable supply of natural gas to meet domestic demand. The GSTC received base funding from the U.S. Department of Energy's (DOE) National Energy Technology Laboratory (NETL) Oil & Natural Gas Supply Program. The GSTC base funds were highly leveraged with industry funding for individual projects. Since its inception, the GSTC has engaged 67 members. The GSTC membership base was diverse, coming from 19 states, the District of Columbia, and Canada. The membership was comprised of natural gas storage field operators, service companies, industry ...

2010-09-30

481

Gamma irradiation in the control of pathogenic bacteria in refrigerated ground chicken meat; Irradiacao gama no controle de bacterias patogenicas em carne de frango refrigerada  

Energy Technology Data Exchange (ETDEWEB)

This work evaluated the effect of gamma radiation on reducing the population of Staphylococcus aureus, Escherichia coli nd Salmonella typhimurium in ground chicken breast stored under refrigeration. The experiment included a control and 4 doses of gamma radiation ( 2.0, 4.0, 6.0 and 8.0 kGy) along with 5 periods of storage under refrigeration ( 1, 7 14, 21 and 28 days). Samples of ground chicken breast were inoculated with Staphylococcus aureus (ATCC 14458), Escherichia coli (ATCC 11105) and Salmonella typhimurium (ATCC 0626), irradiated at temperatures between 4 and 8 deg C and stored under refrigeration (5 deg C) for 28 days. The increased radiation dose and period of storage under refrigeration caused a reduction of Staphylococcus aureus, Escherichia coli and Salmonella typhimurium populations in the ground chicken breast. Mean radiation D values determined for Staphylococcus aureus and Escherichia coli were 0.41 and 0.72 kGy, respectively. Gamma irradiation was an effective ...

2000-09-01

482

Galaxy Group at z=0.3 Associated with the Damped Lyman Alpha System Towards Quasar Q1127-145  

CERN Document Server

We performed a spectroscopic galaxy survey, complete to $m_{F814W}\\leq20.3$ ($L_B>0.15L_B^{\\star}$ at z=0.3), within 100x100'' of the quasar Q1127-145 ($z_{em}=1.18$). The VLT/UVES quasar spectrum contains three $z_{abs}<0.33$ MgII absorption systems. We obtained eight new galaxy redshifts, adding to the four previously known, and galaxy star formation rates (SFRs) and metallicities were computed where possible. A strong MgII system [$W_r(2796)=1.8$A], which is a known damped Ly$\\alpha$ absorber (DLA), had three previously identified galaxies; we found two additional galaxies associated with this system. These five galaxies form a group with diverse properties, such as a luminosity range of $0.04\\leq L_B\\leq0.63 L_B^{\\star}$, an impact parameter range of $17\\leq D \\leq 241$ kpc and velocity dispersion of $\\sigma$=115 km/s. The DLA group galaxy redshifts span beyond the 350 km/s velocity spread of the metallic absorption lines of the DLA itself. The ...

2010-01-01

483

Effects of holmium laser on dental structure in vivo: thermal evaluation and histological analysis on pulpal tissue; Efeitos in vivo do laser de holmio em estrutura dental: monitoracao termica e analise histologica do tecido pulpar  

Energy Technology Data Exchange (ETDEWEB)

Previous in vitro studies have demonstrated that Ho:YLF laser is capable of inducing physical and chemical changes on dental surfaces treated for caries prevention. The temperature in the pulp chamber was in vitro evaluated to as a function of the power and frequency of the laser irradiation. The purpose of this work is to verify the occurrence of pulp inflammation after Ho:YLF laser irradiation using different parameters in rabbits' teeth. The premolars and molars of ten rabbits (NZB) were divided in two groups according to the irradiation energy values of a Ho:YLF laser prototype operating at 2.065{mu}m wave length, frequency of O,5Hz and pulse length of 250{mu}s. An group A teeth were irradiated with using ten pulses of 334mJ/pulse of a Ho:YLF laser prototype operating at O.5Hz, and group B, with 512mJ/pulse. Animals were killed by transcardiac perfusion and the samples were prepared for histopathological analysis. The in vitro temperature monitoring revealed an increase of ...

2001-07-01

484

Determination of volatiles produced during radiation processing in food and medicinal herbs; Determinacao de volateis produzidos durante o processamento por radiacao em ervas alimenticias e medicinais  

Energy Technology Data Exchange (ETDEWEB)

In order to protect food from pathogenic microorganisms as well as to increase its shelf life while keeping sensorial properties (e.g. odor and taste), once the latter are one of the main properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. The aim of the present study was to analyze volatile formation from Co irradiation of Laurus Cinnamomum, Piper Nigrum, Origanum Vulgare and Myristica Fragans. Possible changes on the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties in order to allow better application of irradiation technology. l he samples have been irradiated in plastic packages by making use of a {sup 60}Co Gamma irradiator. Irradiation doses of 0, 5, 10, 15, 20 and 25kGy have been tested. For the analysis of the samples, SPME has been applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation has promoted mostly ...

2008-07-01

485

D & D screening risk evaluation guidance  

Energy Technology Data Exchange (ETDEWEB)

The Screening Risk Evaluation (SRE) guidance document is a set of guidelines provided for the uniform implementation of SREs performed on decontamination and decommissioning (D&D) facilities. Although this method has been developed for D&D facilities, it can be used for transition (EM-60) facilities as well. The SRE guidance produces screening risk scores reflecting levels of risk through the use of risk ranking indices. Five types of possible risk are calculated from the SRE: current releases, worker exposures, future releases, physical hazards, and criticality. The Current Release Index (CRI) calculates the current risk to human health and the environment, exterior to the building, from ongoing or probable releases within a one-year time period. The Worker Exposure Index (WEI) calculates the current risk to workers, occupants and visitors inside contaminated D&D facilities due to contaminant exposure. The Future Release Index (FRI) calculates the ...

1995-09-01

486

Coilgun Launcher for Nanosatellites  

Energy Technology Data Exchange (ETDEWEB)

Nanosatellite space launches could significantly benefit from an electrically powered launch complex, based on an electromagnetic coil launcher. This paper presents results of studies to estimate the required launcher parameters and some fixed facility issues. This study is based on electromagnetic launch, or electromagnetic gun technology, which is constrained to a coaxial geometry to take advantage of the efficiency of closely-coupled coils. A baseline configuration for analysis considers a payload mass of 10 kg, launch velocity of 6 km/s, a second stage solid booster for orbital insertion, and a payload fraction of about 0.1. The launch facility is envisioned as an inclined track, 1-2 km in length, mounted on a hillside at 25 degrees aimed in the orbital inclination of interest. The launcher energy and power requirements fall in the range of 2000 MJ and 2 MW electric. This energy would be supplied by 400 modules of energy storage and magnetic coils. With a prime power generator of 2 ...

1999-03-23

487

Aquatic macroinvertebrates and water quality of Sandia Canyon, Los Alamos National Laboratory, December 1992--October 1993. Status report  

International Nuclear Information System (INIS)

In the summer of 1990, an accidental spill from the TA-3 Power Plant Environment Tank released more than 3,785 liters of sulfuric acid into upper Sandia Canyon. The Biological Resource Evaluation Team (BRET) of EM-8 at Los Alamos National Laboratory (LANL) has collected aquatic samples from the stream within Sandia Canyon since then. These field studies gather water quality measurements and collect macroinvertebrates from permanent sampling sites. An earlier report by Bennett (1994) discusses previous BRET aquatic studies in Sandia Canyon. This report updates and expands Bennett's initial findings. During 1993, BRET collected water quality data and aquatic macroinvertebrates at five permanent stations within the canyon. The substrates of the upper three stations are largely sands and silts while the substrates of the two lower stations are largely rock and cobbles. The two upstream stations are located near outfalls that discharge industrial and sanitary waste ...

2004-06-01

488

Alternative fuel buses currently in use in China: Life-cycle fossil energy use, GHG emissions and policy recommendations  

International Nuclear Information System (INIS)

The Chinese government has enacted policies to promote alternative vehicle fuels (AVFs) and alternative fuel vehicles (AFVs), including city bus fleets. The life cycle (LC), energy savings (ES) and GHG reduction (GR) profiles of AVFs/AFVs are critical to those policy decisions. The well-to-wheels module of the Tsinghua-CA3EM model is employed to investigate actual performance data. Compared with conventional buses, AFVs offer differences in performance in terms of both ES and GR. Only half of the AFVs analyzed demonstrate dual benefits. However, all non-oil/gas pathways can substitute oil/gas with coal. Current policies seek to promote technology improvements and market creation initiatives within the guiding framework of national-level diversification and district-level uniformity. Combined with their actual LC behavior and in keeping with near- and long-term strategies, integrated policies should seek to (1) apply hybrid electric technology to diesel buses; (2) ...

2010-01-01

489

A comparison of algorithms for inference and learning in probabilistic graphical models.  

Science.gov (United States)

Research into methods for reasoning under uncertainty is currently one of the most exciting areas of artificial intelligence, largely because it has recently become possible to record, store, and process large amounts of data. While impressive achievements have been made in pattern classification problems such as handwritten character recognition, face detection, speaker identification, and prediction of gene function, it is even more exciting that researchers are on the verge of introducing systems that can perform large-scale combinatorial analyses of data, decomposing the data into interacting components. For example, computational methods for automatic scene analysis are now emerging in the computer vision community. These methods decompose an input image into its constituent objects, lighting conditions, motion patterns, etc. Two of the main challenges are finding effective representations and models in specific applications and finding efficient algorithms for inference and ...

2005-09-01

490

Upgrading low molecular weight hydrocarbons  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a process for the conversion of low molecular weight alkanes to higher molecular weight hydrocarbons. It comprises: contacting the low molecular weight alkanes, at an elevated temperature, with oxygen and a catalyst of the formula Zn{sub a}A{sub b}M{sub c}M'{sub d}O{sub x} wherein A is Li, Na, K, or mixtures thereof; M is Al, Ga, Cr, La, Y, Sc, V, Nb, Ta, Cu or mixtures thereof; M' is Cs, Rb, Mg, Ca, Sr, Ba, Sm, Pb, Mn, Sb, P, Sn, Bi, Ti, Zr, Hf, or mixtures thereof; a if from about 1 to about 20; b is from about 0.1 to about 20; c is from about 0 to about 5 d is from about 0 to about 20, and x is a number needed to fulfill the valence requirements of the other elements; provided that at least one c and d is a t least 0.1; and when M' is Sn, c must be at least 0.1.

1989-12-12

491

Trace metal concentrations in estuaries and coastal regions  

Energy Technology Data Exchange (ETDEWEB)

Estuaries and coastal regions are highly variable in the physical and hydrographic conditions. As a result of heavy urbanization and industrialization of the head waters of most estuaries, there are substantial localized inputs of contaminants to the estuary. These factors combined with the flushing characteristics of individual estuaries to create relatively unique features that result in variation in the typical levels of trace metals for these systems. This makes intercomparison of the estuaries difficult. Comparability among estuaries becomes even more difficult when metals analyses are conducted without proper control of field and laboratory contamination, now firmly established in the trace metal analytical literature as a prerequisite for reliable marine trace metals analysis. This paper compares the concentrations of selected trace metal (Ag, Cd, Cu, Ni, Pb, and Zn) concentrations in the waters of several major estuaries of the United States. The basis of ...

1994-12-31

492

Thermal effect on superhydrophobic performance of stearic acid modified ZnO nanotowers  

Energy Technology Data Exchange (ETDEWEB)

The thermal desorption of stearic acid on superhydrophobic zinc oxide nanotowers has been investigated. The stearic acid passivated zinc oxide nanotowers provide a very high contact angle of {approx}173 {+-} 1.1 deg. with a very low hysteresis of {approx}1.4 {+-} 0.5 deg. due to the presence of a binary structure composed of several nanosteps on each nanotower of height {approx}700 nm that eventually reduces the area of contact between the drop and the nanotowers and trapping more air as revealed by the field emission scanning electron microscopy images. The superhydrophobic performance of these nanotowers, however, declines following annealing at elevated temperatures. Fourier transform infrared spectra show a reduction in the intensity of stearic acid -CH{sub n} peaks at elevated temperatures revealing the cause of the decrease in contact angle and confirming the occurrence of thermal desorption at 184 deg. C. The corresponding activation energy for desorption determined from our ...

2008-02-28

493

Solid electrolyte and lithium battery employing it. Kotai denkaishitsu oyobi sore wo shiyo shite naru richiumu denchi  

Energy Technology Data Exchange (ETDEWEB)

Recently, the lithium ion-conductive solid electrolyte draws attention because there is a possibility of producing the maintenance-free battery which is characterized by having such advantages as high energy density and no possibility of electrolyte leak because of solid state structure. The invented lithium ion-conductive solid electrolyte is formed by sintering the granular electrolyte expressed in the following general formula: Li(1+(4-n)x)MxTi(2-x)(PO4)3 (M = mono- or di-valent cation, x = 0.1 - 0.5). Examples of the monovalent cation are Na[sup +], K[sup +], Rb[sup +], Cs[sup +], and Cu[sup +]. Examples of divalent cation are Mg[sup 2+], Fe[sup 2+], Be[sup 2+], Ca[sup 2+], Sr[sup 2+], Ba[sup 2+], Ra[sup 2+], Mn[sup 2+], Co[sup 2+], Cu[sup 2+], Ni[sup 2+], Zn[sup 2+], and Cd[sup 2+]. The electric conductivity of lithium ion is increased with the increase in the content of Li[sup +] in the electrolyte. 4 figs.

1993-11-12

494

Selective adsorption of uranium on activated charcoal from electrolytic aqueous solutions  

Energy Technology Data Exchange (ETDEWEB)

Adsorption of uranium onto various solids is important from purification, environmental, and radioactive waste disposal points of view. Adsorption of uranium on activated charcoal has been studied as a function of shaking time, amount of adsorbent, pH, concentration of adsorbate, and temperature. Uranium adsorption obeys the Langmuir isotherm. {Delta}H{degrees} and {Delta}S{degrees} were calculated from the slope and intercept of plots ln K{sub D} vs 1/T. The influence of different anions and cations on uranium adsorption has been examined. The adsorption of other metal ions on activated charcoal has been studied under specified conditions to check its selectivity; consequently, uranium was removed from Cs, Ba, Zn, and Co. More than 98% adsorbed uranium on activated charcoal can be recovered with 65 ml of 3 M HNO{sub 3} solution. A wavelength dispersive x-ray fluorescence spectrometer was used for measuring uranium concentration.

1992-02-01

495

Multielement determination of major-to-ultratrace elements in salmon egg by ICP-AES and ICP-MS  

Energy Technology Data Exchange (ETDEWEB)

The multielement determination of major-to-ultratrace elements in salmon egg was carried out by ICP-AES and ICP-MS. First, salmon eggs (30 eggs used) were digested with conc. nitric acid and 60% perchloric acid by heating almost to dryness repeatedly. Finally, the residues of salmon eggs were dissolved in 1 M nitric acid and the sample solutions were analyzed by ICP-AES and ICP-MS. About 40 elements could be determined over the concentration range in 9 orders of magnitude. The concentrations of bio-essential elements, such as Zn, Fe, and Cu, in salmon egg were 10-100 times higher than those in human blood serum. In addition, the major-to-ultratrace elements in cell cytoplasm and cell membrane were separately determined in a similar manner to those in whole egg cell. The concentrations of most bio-essential elements were higher in cell cytoplasm than in cell membrane, while those of Fe and Cu were higher in cell membrane than in cell cytoplasm of salmon egg. ...

2002-04-01

496

Measuring characteristics on emissivity using infrared thermometer for RCCS  

International Nuclear Information System (INIS)

In VHTGR (Very High Temperature Gas-cooled Reactor), the radiation plays an important role in heat transfer through the cavity in RCCS (Reactor Cavity Cooling System). We performed the series of experiments to measure the emissivity using the infrared thermometer with wavelength range of 8#approx#14 #mu#m. As the first step, the transmittance of Zinc Selenide (ZnSe) window was measured to estimate the emissivity that can compensate the attenuation effect of window. The kind of gas with various concentrations in the cavity will be released during postulated accidents to the coolant type, so it is essential to estimate the effects of gas on the measurement of emissivity. In this manner we measured the emissivity with the air, the helium and the steam inside chamber. The results represent that the concentration of the air and the helium do not affect the emissivity significantly while the steam decreases the measured emissivity relatively. It means that the air and ...

2004-12-01

497

Design of pilot-scale constructed wetlands for tertiary treatment of refinery effluent  

Energy Technology Data Exchange (ETDEWEB)

Two pilot-scale constructed wetlands (4:1 length:width aspect) were designed for tertiary treatment of refinery effluent. As requirements for removal of contaminants from NPDES effluents become more stringent, cost-effective technological approaches are needed to achieve the necessary treatment levels and be efficient, effective and low maintenance. The fundamental design of these constructed wetlands was based on biogeochemical principles that regulate the fate and persistence of the targeted elements (Cu, Zn, Pb). In order to maximize opportunities to learn more about the internal function of the wetlands, they were built to operate in series or in parallel permitting hydraulic retention times of 24 to 48 hours. The wetlands were lined with {approximately}76 cm of compacted clay as well as a 30 mil polyethylene liner. The hydrosoil selected for use in the constructed wetlands is 74.1% sand, 25.6% silt, 0.3% clay. Based on laboratory studies, this hydrosoil ...

1994-12-31

498

D3+D6 solution and D4+D6 solution  

International Nuclear Information System (INIS)

We make the supergravity solutions describing the branes (D3 branes and D4 branes) localized within the D6 branes in the near core region of D6 brane. From the D=11 solutions (M3 branes and M4 branes with the Z_N identifications in the transverse space) we obtain the D=10 supergravity solutions of D3 branes localized within D6 branes and D4 branes localized within D6 branes by reducing the dimension down to D=10 along a circular direction of S"3 part of the transverse space. M3 brane solution leads to D=10 background representing D3 branes localized on D6 branes in the region close to the D6 branes core. M4 branes lead to the D4 branes localized on D6 branes in the region close to the D6 brane core.

2001-04-16

499

Artificial receptor for peptide recognition in protic media: The role of metal ion coordination  

International Nuclear Information System (INIS)

The production of molecularly imprinted polymers (MIPs) for the recognition of C-terminal cholecystokinin pentapeptide (CCK-5) in the presence of metal ion is reported. The MIPs were produced under the same molar ratio of template to monomers (acrylamide, N,N'-methylene bisacrylamide) in the presence or absence of nitrilotriacetic acid-nickel (Ni-NTA) complex. Scanning electron microscopy images of MIPs were obtained in an attempt to correlate the adsorption characteristics with polymer's morphology. Subsequently Ni2+ was removed and substituted by other divalent ions such as Mg2+, Fe2+, Zn2+, Co2+ and Cu2+. It was found that polymers containing the metal ion complex with the order Fe-NTA, Ni-NTA and Cu-NTA presented lower dissociation constant values than the rest thus exhibiting stronger guest binding activity. The percentage of theoretical maximum binding sites Bmax was almost the same for these ions, indicating that the ion-template coordination is responsible ...

2008-08-25

500

Amorphous metal alloy compositions for reversible hydrogen storage and electrodes made therefrom  

Energy Technology Data Exchange (ETDEWEB)

This patent describes an energy storage device. It comprises: a working electrode, a counter electrode, electrically isolated from the working electrode; an electrolyte in contact with the working electrode and the counter electrode, and means for collecting electrical current therefrom; the working electrode consisting essentially of an amorphous metal alloy of the formula: A{sub {ital a}}M{sub {ital b}}M{prime}{sub {ital c}}, wherein A is at least one metal selected from the group consisting of Ag, Hg and Pt; M is at least one metal selected from the group consisting of Pb, Cu, Cr, Mo, W, Ni, Al, Co, Fe, Zn, Ru, Cd and Mn; M{prime} is at lest one of the elements selected from the group consisting of Ca, Mg, Ti, Zr, Hf, V, Nb and Ta; and wherein a ranges from about 0.005 to about 0.80; b ranges from 0.05 to about 0.70; and c ranges from about 0.08 to about 0.95.

1990-05-08