Bulk

Distribution by Scientific Domains
Distribution within Polymers and Materials Science

Kinds of Bulk

  • steric bulk

  • Terms modified by Bulk

  • bulk aqueous phase
  • bulk chemical
  • bulk composition
  • bulk concentration
  • bulk conductivity
  • bulk counterpart
  • bulk crystal
  • bulk defect
  • bulk degradation
  • bulk density
  • bulk diffusion
  • bulk film
  • bulk flow
  • bulk gan substrate
  • bulk heterojunction
  • bulk heterojunction organic solar cell
  • bulk heterojunction solar cell
  • bulk liquid
  • bulk lorentz factor
  • bulk material
  • bulk metal
  • bulk metallic glass
  • bulk metallic glasses
  • bulk modulus
  • bulk motion
  • bulk organic carbon
  • bulk organic matter
  • bulk phase
  • bulk plasticity
  • bulk polymer
  • bulk polymerization
  • bulk powder
  • bulk property
  • bulk quantity
  • bulk sample
  • bulk sediment
  • bulk single crystal
  • bulk soil
  • bulk solution
  • bulk solvent
  • bulk specimen
  • bulk state
  • bulk storage
  • bulk structure
  • bulk system
  • bulk temperature
  • bulk value
  • bulk viscosity
  • bulk water

  • Selected Abstracts


    Bulk-solvent correction for fast translation search in molecular replacement: service programs for AMoRe and CNS

    JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2003
    Andrei Fokine
    A new software package, BULK, was developed to allow fast and easy use of low-resolution data for the translation problem in molecular replacement. When the search model is relatively complete but not precise, or when its orientation is imprecisely determined, low-resolution data contribute very favourably to the solution of the translation-search problem. BULK comprises a specially developed program and a set of procedures complementary to the program AMoRe, as well as an input file for the CNS suite. [source]


    Facile Synthesis of Bastnaesite -Type LaF[CO3] and Its Thermal Decomposition to LaOF for Bulk and Eu3+ -Doped Samples

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 3 2009
    Oliver Janka
    Abstract Rare-earth metal(III) oxide fluorides with the composition MOF (M = La,Lu) seem to offer promising host lattices for luminescence applications by doping these materials with trivalent lanthanoid cations. Unfortunately, there was no simple and practicable way to synthesize the compounds in phase-pure quality with classical solid-state chemistry reactions. However, by using the rare-earth metal(III) fluoride oxocarbonates, MF[CO3], as solution-born precursor materials that crystallize with a bastnaesite -type structure, easy access is now possible by mild thermal decomposition. Synthetic details, investigations on the phase purity and the presence of the oxocarbonate anion [CO3]2, proved by IR measurements as well as from X-ray powder diffraction data are given in this paper for the example of bulk LaF[CO3] and Eu3+ -doped samples. The latter (LaF[CO3]:Eu3+) shows a bright orange-red luminescence that is stronger than that of the product of its thermal decomposition: trimorphic LaOF:Eu3+.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


    Plasticity and Grain Boundary Diffusion at Small Grain Sizes,

    ADVANCED ENGINEERING MATERIALS, Issue 8 2010
    Gerhard Wilde
    Bulk nanostructured,or ultrafine-grained materials are often fabricated by severe plastic deformation to break down the grain size by dislocation accumulation. Underlying the often spectacular property enhancement that forms the basis for a wide range of potential applications is a modification of the volume fraction of the grain boundaries. Yet, along with the property enhancements, several important questions arise concerning the accommodation of external stresses if dislocation-based processes are not longer dominant at small grain sizes. One question concerns so-called "non-equilibrium" grain boundaries that have been postulated to form during severe deformation and that might be of importance not only for the property enhancement known already today, but also for spectacular applications in the context of, e.g., gas permeation or fast matter transport for self-repairing structures. This contribution addresses the underlying issues by combining quantitative microstructure analysis at high resolution with grain boundary diffusion measurements. [source]


    In Situ Observation of Dynamic Recrystallization in the Bulk of Zirconium Alloy (Adv. Eng.

    ADVANCED ENGINEERING MATERIALS, Issue 8 2009
    Mater.
    The cover shows the in-situ diffraction setup. A fine synchrotron beam transmits the sample situated in a (heated) load frame and scatters into Debye-Scherrer cones. Large crystallites map onto spots onto the 2D detector rather than continuous rings. In the background, the intensity distribution of one selected reflection - here beta-Zr 110 - is plotted in color scale as a function of azimuthal angle (horizontal axis) and time (vertical axis) revealing the different states during thermo-mechanical processing. More details can be found in the article by K.-D. Liss on page 637. [source]


    In Situ Observation of Dynamic Recrystallization in the Bulk of Zirconium Alloy,

    ADVANCED ENGINEERING MATERIALS, Issue 8 2009
    Klaus-Dieter Liss
    Dynamic recrystallization and related effects have been followed in situ and in real time while a metal undergoes rapid thermo-mechanical processing. Statistics and orientation correlations of embedded/bulk material grains were deduced from two-dimensional X-ray diffraction patterns and give deep insight into the formation of the microstructure. Applications are relevant in materials design, simulation, and in geological systems. [source]


    Bulk and supported tungstophosphoric acid as friendly, efficient, recyclable catalysts for the synthesis of bis-indolylmethanes under solvent-free conditions

    HETEROATOM CHEMISTRY, Issue 6 2009
    Hamid Aliyan
    The treatment of indole with structurally diverse aldehydes in the presence of catalytic amount of inorganic-supported polyoxometalates, heterogeneous, reusable and efficient catalysts at room temperature gave the corresponding bis-indolylmethanes in excellent yields and shorter reaction times under solvent-free conditions. The catalyst can be reused for several times, but it will be less active. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:325,331, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20554 [source]


    Synthesis and Characterization of Bulk, Vitreous Cadmium Germanium Arsenide

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2009
    Bradley R. Johnson
    Cadmium germanium diarsenide glasses were synthesized in bulk form (,2.4 cm3) using procedures adapted from the literature. Several issues involved in the fabrication and quenching of amorphous CdGexAs2 (x=0.45, 0.65, 0.85, and 1.00, where x is the molar ratio of Ge to 1 mol of Cd) are described. An innovative processing route is presented to enable fabrication of high-purity, vitreous, crack-free ingots with sizes up to 10 mm diameter, and 30,40 mm long. Specimens from selected ingots were characterized using thermal analysis, optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, particle-induced X-ray emission, Rutherford backscattering, secondary ion mass spectrometry, X-ray diffraction, density, and optical spectroscopy. Variations in properties as a function of processing conditions and composition are described. Results show that the density of defect states in the middle of the band gap and near the band edges can be decreased three ways: through suitable control of the processing conditions, by doping the material with hydrogen, and by increasing the concentration of Ge in the glass. [source]


    Crystallographic Orientation of Y2Ba4CuMOx (M=Nb, Zr, Ag) Nanoparticles Embedded in Bulk, Melt-Textured YBCO Studied by EBSD

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2007
    A. Koblischka-Veneva
    Crystallographic orientations of Y,Ba,Cu,O (YBCO) and embedded Y2Ba4CuMOx (M=Nb, Zr, Ag) nanoparticles in bulk, melt-textured YBCO samples are studied by electron backscatter diffraction. Y2BaCuO5 particles exhibit no preferred orientation but have a strong negative influence on the matrix orientation. In contrast, the nanoparticles do not disturb the texture of the YBCO matrix. Depending on the preparation route, a different particle orientation with respect to the matrix is obtained. Untextured nanoparticles are formed by solid-state reaction during the melt process by adding oxides (Nb2O5 or Y2O3) to the precursor powder. Preformed Y2Ba4CuMOx particles added to the precursor in the form of prereacted nanopowder exhibit a dominant single orientation related to the surrounding YBCO matrix. [source]


    Enhanced ability of regulatory T cells in chronic hepatitis C patients with persistently normal alanine aminotransferase levels than those with active hepatitis

    JOURNAL OF VIRAL HEPATITIS, Issue 12 2009
    I. Itose
    Summary., In hepatitis C virus (HCV) infection, the Th1-type immune response is involved in liver injury. A predominance of immunosuppressive regulatory T cells (Treg) is hypothesized in patients with persistently normal alanine aminotransferase (PNALT). Our aim was to clarify the role of Treg in the pathogenesis of PNALT. Fifteen chronically HCV-infected patients with PNALT, 21 with elevated ALT (CH) and 19 healthy subjects (HS) were enrolled. We determined naturally-occurring Treg (N-Treg) as CD4+CD25high+FOXP3+ T cells. The expression of FOXP3 and CTLA4 in CD4+CD25high+ cells was quantified by real-time reverse transcriptase-polymerase chain reaction. Bulk or CD25-depleted CD4+ T cells cultured with HCV-NS5 loaded dendritic cells were assayed for their proliferation and cytokine release. We examined CD127,CD25,FOXP3+ cells as distinct subsets other than CD25+ N-Treg. The frequencies of N-Treg in patients were significantly higher than those in HS. The FOXP3 and CTLA4 transcripts were higher in PNALT than those in CH. The depletion of CD25+ cells enhanced HCV-specific T cell responses, showing that co-existing CD25+ cells are suppressive. Such inhibitory capacity was more potent in PNALT. The frequency of CD4+CD127,CD25,FOXP3+ cells was higher in CH than those in PNALT. Treg are more abundant in HCV-infected patients, and their suppressor ability is more potent in patients with PNALT than in those with active hepatitis. [source]


    Soil restorative effects of mulching on aggregation and carbon sequestration in a Miamian soil in central Ohio

    LAND DEGRADATION AND DEVELOPMENT, Issue 5 2003
    G. S. Saroa
    Abstract Soils play a key role in the global carbon cycle, and can be a source or a sink of atmospheric carbon (C). Thus, the effect of land use and management on soil C dynamics needs to be quantified. This study was conducted to assess: (1) the role of aggregation in enhancing soil organic carbon (SOC) and total soil nitrogen (TSN) concentrations for different mulch rates, (2) the association of SOC and TSN with different particle size fractions, and (3) the temporal changes in the SOC concentration within aggregate and particle size fractions with duration of mulching. Two experiments were initiated, one each in 1989 and 1996, on a Crosby silt loam (Aeric Ochraqualf or Stagnic Luvisol) in central Ohio. Mulch treatments were 0, 8, and 16,Mg,ha,1,yr,1 without crop cultivation. Soil samples from 0,5,cm and 5,10,cm depths were obtained in November 2000; 4 and 11 years after initiating the experiments. Mulch rate significantly increased SOC and TSN concentrations in the 0,5,cm soil layer only. The variation in the SOC concentration attributed to the mulch rate was 41 per,cent after 4 years of mulching and 52 per,cent after 11 years of mulching. There were also differences in SOC and TSN concentrations among large aggregate size fractions, up to 2,mm size after 4 years and up to 0,5,mm after 11 years of mulching. There were also differences in SOC and TSN concentrations among particle size fractions. Variation in the SOC concentration in relation to particle size was attributed to clay by 45,51 per,cent, silt by 34,36 per,cent, and to sand fraction by 15,19 per,cent. Bulk of the TSN (62,67 per,cent) was associated with clay fraction and the rest was equally distributed between silt and sand fractions. The enrichment of SOC and TSN concentrations in the clay fraction increased with depth. The C:N ratio was not affected by the mulch rate, but differed significantly among particle size fractions; being in the order of sand >silt >clay. Copyright © 2003 John Wiley & Sons, Ltd. [source]


    Effect of Surface Modification on the Synthesis of Pore-Filling Polymeric Monoliths in Microfiltration Membranes Made from Poly(propylene) and Poly(ethylene terephthalate)

    MACROMOLECULAR MATERIALS & ENGINEERING, Issue 3 2007
    Abdus Salam
    Abstract The effect of pre-modification on the interaction of macroporous substrates (membranes) with mainly micro- and mesoporous polymer monoliths has been studied. Bulk, porous polymer monoliths were synthesized to optimize the synthesis conditions and their pore morphology, and the data were used as benchmark for this study. Pre-modification of the entire pore surface of PP microfiltration membranes and PET track-etched membranes by UV-initiated grafting with PEGMA was performed using well-established methods, including coating with the photo-initiator, benzophenone. Subsequently, these membranes were functionalized by filling the pores with porous polymer monoliths from MAA and EDMA and compared with membranes that had been functionalized without the pre-modification step. The materials were characterized mainly by the degree of grafting, SEM and by the gas-adsorption-isotherm method. The DG values, after composite-membrane preparation under identical conditions, were not influenced by the pre-modification. However, it could be clearly seen from the SEM images that the pre-modification step prevents the formation of voids at the monolith-membrane pore interface. Larger specific surface area and pore volume values for composite membranes, prepared after pre-modification, fully support the SEM results. Especially large differences in pore structure between the two different composite membranes were found in the mesopore range. The results of this study indicate that it is possible to prepare porous, composite membranes where the trans-membrane transport is exclusively controlled by the pore and surface structure of a functional polymeric monolith, for example, made from a molecularly-imprinted polymer. [source]


    Stereoselective Complex Formation between Polybutadiene and Cyclodextrins in Bulk

    MACROMOLECULAR RAPID COMMUNICATIONS, Issue 11 2008
    Yukari Kuratomi
    Abstract Polybutadienes (PBs) are found to form inclusion complexes with cyclodextrins (CDs) stereoselectively to give crystalline compounds in bulk. These complexes have been isolated and characterized by means of 1H NMR and 13C CP/MAS NMR spectroscopy, and X-ray diffraction. Although , -CD did not form inclusion complexes with any kinds of PBs in aqueous solutions, , -CD did form inclusion complexes with PBs having 1,4- cis - and 1,4- trans -butadiene units in bulk by heating at 100,°C. On the other hand, PB having 79% of a 1,2-structure did not form inclusion complexes with , -CD. The yield of the inclusion complexes increases with an increase in the content of the 1,4- cis -structure of PB and decreases with the molecular weights of the PBs. [source]


    Nitroxide-Mediated Bulk and Miniemulsion Polymerization in a Continuous Tubular Reactor: Synthesis of Homo-, Di- and Triblock Copolymers

    MACROMOLECULAR REACTION ENGINEERING, Issue 3-4 2010
    Thomas E. Enright
    Abstract In previous work, a modified nitroxide-mediated miniemulsion polymerization was demonstrated in a continuous tubular reactor to prepare a latex of polystyrene homopolymer dispersed in water. There, the initial reaction step (low conversion bulk polymerization to prepare the macroinitiator) was done in a batch reactor while the miniemulsion polymerization step was done in a continuous tubular reactor. The present paper describes an extension of that work in which all the reaction steps have been achieved in the continuous tubular reactor. Chain extension of the polystyrene latex to give polystyrene- block -poly(butyl acrylate) diblock and polystyrene- block -poly(butyl acrylate)- block -polystyrene triblock copolymers is also described. [source]


    The Kinetic Modeling of Strong Diffusion-Limited Reaction with Cyclization for Three Isomers , Diallyl Ortho-, Iso- and Tere - Phthalate in a Bulk

    MACROMOLECULAR REACTION ENGINEERING, Issue 3 2007
    Iztok Hace
    Abstract Free radical polymerization kinetic in a bulk for three diallyl phthalate isomers , diallyl orthophthalate, diallyl isophthalate and diallyl terephthalate was investigated in a temperature range from 50 to 70,°C initiated with dicyclohexan peroxydicarbonate as initiator at three different initiator concentrations. Conversion points were measured using Fourier Transform Raman measurements. A new kinetic model for polymerization of three diallyl phthalate isomers was developed. It demands the inclusion of only two new kinetic parameters kDegC and kpc which were obtained as a ratio kDegC/kpc from an additional set of experiments conducted. Computed conversions from the proposed kinetic model show good agreement with the conversion and molecular weight measured data for all three investigated diallyl phthalate isomers. [source]


    Kinetic Study of the Thermopolymerization of Furfuryl Methacrylate in Bulk by Mathematical Modeling.

    MACROMOLECULAR THEORY AND SIMULATIONS, Issue 9 2009
    Part A: Simulation of Experimental Data, Sensitivity Analysis of Kinetic Parameters
    Abstract Mathematical modeling of the thermopolymerization of FM and CMFMA was carried out using a cross-linked kinetic model proposed for the photo-initiated polymerization of acryl-furanic compounds. In this model, the photochemical initiation step was substituted by a thermal one and it was assumed that the constant of radical termination was time-dependent, which allowed the gel effect (Trommsdorff) at high monomer conversion to be simulated. Optimization of all kinetic constants was achieved and the results of simulation suitably fitted the experimental data of the monomer conversion. The contribution of each step in the mechanism and its dependence on the experimental conditions were estimated by a sensitivity analysis technique. [source]


    40Ar- 39Ar age determinations of lunar basalt meteorites Asuka 881757, Yamato 793169, Miller Range 05035, La Paz Icefield 02205, Northwest Africa 479, and basaltic breccia Elephant Moraine 96008

    METEORITICS & PLANETARY SCIENCE, Issue 6 2009
    Vera A. FERNANDES
    Stepped heating 40Ar- 39Ar analyses of several bulk fragments of related meteorites A-881757, Y-793169 and MIL 05035 give crystallization ages of 3.763 ± 0.046 Ga, 3.811 ± 0.098 Ga and 3.845 ± 0.014 Ga, which are comparable with previous age determinations by Sm-Nd, U-Pb Th-Pb, Pb-Pb, and Rb-Sr methods. These three meteorites differ in the degree of secondary 40Ar loss with Y-793169 showing relatively high Ar loss probably during an impact event ,200 Ma ago, lower Ar loss in MIL 05035 and no loss in A-881757. Bulk and impact melt glass-bearing samples of LAP 02205 gave similar ages (2.985 ± 0.016 Ga and 2.874 ± 0.056 Ga) and are consistent with ages previously determined using other isotope pairs. The basaltic portion of EET 96008 gives an age of 2.650 ± 0.086 Ga which is considered to be the crystallization age of the basalt in this meteorite. The Ar release for fragmental basaltic breccia EET 96008 shows evidence of an impact event at 631 ± 20 Ma. The crystallization age of 2.721 ± 0.040 Ga determined for NWA 479 is indistinguishable from the weighted mean age obtained from three samples of NWA 032 supporting the proposal that these meteorites are paired. The similarity of 40Ar- 39Ar ages with ages determined by other isotopic systems for multiple meteorites suggests that the K-Ar isotopic system is robust for meteorites that have experienced a significant shock event and not a prolonged heating regime. [source]


    Bulk and patch ferrite resonator antennas based on the ceramic matrix composite: GdIGx YIG1- x

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2009
    P. B. A. Fechine
    Abstract In this study, the dielectric properties of the GdIGXYIG1,X ferrite composite material at radio frequency (RF) and microwave frequency bands were studied. These measurements were carried out in different sample geometries: thick films and cylindrical ceramic bulk ferrite resonator. In the RF range, we observed that the material is rather stable because of its short changes as a function of temperature and frequency range. The temperature capacitance coefficient values for all the samples (thick films and cylindrical ceramic bulk samples) presented short positive values at the RF range. The GdIG0.5YIG0.5 thick film was used as a substrate for the microstrip antenna device, where the upper Ag electrode served as a circular patch antenna and a microstrip line was used as a feed line. The microstrip antenna operates in this configuration at 8.185 GHz. In the study of the dielectric properties of the composites antenna geometry, with the same ferrite composite, a bulk cylindrical geometry was investigated. A numerical study, together with the experimental, was done, and the dielectric characteristics of the composite like ,r, tg,E, and ,r were obtained. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1595,1602, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24395 [source]


    Bulk and epitaxial growth of micropipe-free silicon carbide on basal and rhombohedral plane seeds

    PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 7 2008
    B. M. Epelbaum
    Abstract In this paper the criteria for reasonable choice of alternative to (0001) seed orientation are discussed. Growth conditions necessary to produce bulk 6H- and 4H-SiC crystals on rhombohedral (01-1n) plane seeds in PVT process are presented. Specific defect structures in such crystals are described in relation to growth conditions. In the second part of the paper, liquid phase epitaxial (LPE) growth using high-temperature silicon based flux and rhombohedral plane seeds is compared to the LPE on basal plane seeds. In both bulk and epitaxial growth processes the employment of rhombohedral plane seed offers important advantages. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Bulk nanostructured titanium fabricated by hydrostatic extrusion

    PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 5 2010
    Krzysztof Topolski
    Abstract The paper is concerned with the use of Hydrostatic Extrusion (HE), which is one of the methods of Severe Plastic Deformation (SPD), for grain refinement of titanium grade 2. Titanium in the form of rods was subjected to multi-stage extrusion. The aim was to optimize the HE process so as to obtain nanostructured titanium rods. The results show that it is possible to produce nanostructured Ti rods of a diameter suitable for industrial applications. The refinement to nano-sized grains is accompanied by a significant improvement of mechanical properties. The tensile strength of more than 1000MPa was achieved and the hardness increase exceeded 50%. This study was also concerned with the problem of up-scaling the dimensions of nano-refined components produced by HE. The basic condition for HE to yield nanostructured Ti is that an appropriately high accumulated strain should be applied (, > 3). The results demonstrate that, by using HE, we can produce nano-Ti rods with diameters amounting to ,8mm. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Multi-objective optimization of an industrial penicillin V bioreactor train using non-dominated sorting genetic algorithm

    BIOTECHNOLOGY & BIOENGINEERING, Issue 3 2007
    Fook Choon Lee
    Abstract Bulk of the penicillin produced is used as raw material for semi-synthetic penicillin (such as amoxicillin and ampicillin) and semi-synthetic cephalosporins (such as cephalexin and cefadroxil). In the present paper, an industrial penicillin V bioreactor train is optimized for multiple objectives simultaneously. An industrial train, comprising a bank of identical bioreactors, is run semi-continuously in a synchronous fashion. The fermentation taking place in a bioreactor is modeled using a morphologically structured mechanism. For multi-objective optimization for two and three objectives, the elitist non-dominated sorting genetic algorithm (NSGA-II) is chosen. Instead of a single optimum as in the traditional optimization, a wide range of optimal design and operating conditions depicting trade-offs of key performance indicators such as batch cycle time, yield, profit and penicillin concentration, is successfully obtained. The effects of design and operating variables on the optimal solutions are discussed in detail. Biotechnol. Bioeng. 2007;98: 586,598. © 2007 Wiley Periodicals, Inc. [source]


    Molecular Precursor Route to Bulk and Silica-Supported Nb2Mo3O14 Using Water-Soluble Oxo-oxalato Complexes.

    CHEMINFORM, Issue 33 2006
    Daisy A. Bayot
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]


    Organic Phase Conversion of Bulk (Wurtzite) ZnO to Nanophase (Wurtzite and Zinc Blende) ZnO.

    CHEMINFORM, Issue 9 2006
    Lauren P. Snedeker
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]


    Growth and electrical properties of flash evaporated AgGaTe2 thin films

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2006
    B. H. Patel
    Abstract Thin films have been prepared by flash evaporation technique of a stoichiometric bulk of AgGaTe2 compound in vacuum and analysed using X-ray diffraction, transmission electron microscopy, selected area diffraction and energy dispersive analysis of X-rays. The effect of substrate temperature on the structural properties , grain size, film orientation, composition, and stoichiometry of the films have been studied. It was found that the polycrystalline, stoichiometric films of AgGaTe2 can be grown in the substrate temperature range of 473K < Ts < 573K. The influence of substrate temperature (Ts) on the electrical characteristics- Resistivity, Hall Mobility, Carrier concentration of AgGaTe2 thin films were studied. The electrical resistivity was found to decrease with increase in substrate temperature up to 573K and then increases. The variation of activation energy of AgGaTe2 thin films were also investigated. The implications are discussed. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    High temperature arsenic doping of CdHgTe epitaxial layers

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 1 2004
    A. Vlasov
    Abstract Experimental results on solid-state arsenic doping of the n-type bulk and ISOVPE epitaxial CdXHg1- XTe (X = 0.19 ÷ 0.3) alloys are presented. The arsenic doped thin epitaxial CdxHg1- xTe films (nAs , 5 · 1016 ÷ 1 · 1020 cm -3; d = 2 ÷ 5 ,m) obtained by RF sputtering in a mercury glow discharge were used as As diffusion sources. The arsenic diffusion and activation were carried out at temperatures T = 500 ÷ 600 °C under Hg vapour pressure. Immediately after the high temperature treatment all samples were annealed to annihilate point defects. The SIMS analysis was used for determination of the quantitative admixture distribution of As in the diffusion area. The arsenic electrical activity has been evaluated by means of differential Hall, resistivity and thermoemf measurements. The analysis of experimental data obtained as well as their comparison with previously obtained results has been performed. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Securing the World and Challenging Civil Society: Before and After the ,War on Terror'

    DEVELOPMENT AND CHANGE, Issue 2 2010
    Jude Howell
    ABSTRACT Following President Bush's declaration of a ,War on Terror' in 2001, governments around the world introduced a range of counter-terrorist legislation, policies and practices. These measures have affected not only human rights and civil liberties but also civil society and aid frameworks. Although the Obama administration has renounced the language of the ,War on Terror' and taken steps to revoke aspects such as water-boarding and the detention facility at Guantanamo Bay, the bulk of the legislation and practices associated with the post-9/11 global security framework remain. The cluster of papers which follow provide detailed studies of the effects of the War on Terror regime on civil society in four contexts: the USA, Spain, Kenya and Uzbekistan. In this way it lays a basis for civil society actors and aid agencies to reflect more strategically on how they should engage with security debates and initiatives in a way that best protects the spaces of civil society and the interests of minority and vulnerable groups. This introduction sets out the three key themes pursued throughout the cluster articles, namely, the selective impact of counter-terrorist measures on civil society; the particularity of civil society responsiveness to these measures; and the role of aid and diplomacy in pursuing security objectives and its consequences for civil society. [source]


    Platelet hyperactivity in clinical depression and the beneficial effect of antidepressant drug treatment: how strong is the evidence?

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2004
    R. Von Känel
    Objective:, Platelet hyperactivity is thought to contribute to the increased coronary artery disease (CAD) risk in depression. This study reviewed the evidence for hyperactive platelets and for effects of antidepressant drug treatment on platelet ,stickiness' in clinical depression. Method:, By means of PubMed electronic library search, 34 studies in English were identified (1983,2003) and critically reviewed. Results:, In depression, flow cytometry studies allowing detection of subtle platelet activation states consistently found at least one platelet activation marker to be increased, while the bulk of platelet aggregation studies did not suggest increased platelet aggregability. Platelets seem to be more activated in depressed patients with CAD than in depressed individuals without CAD. The selective serotonin reuptake inhibitors normalized platelet hyperactivity in four studies. Conclusion:, Data on platelet activity in depression are inconclusive. To resolve this issue and its clinical implications, studies in larger sample sizes controlling for confounders of platelet functioning and prospectively designed are needed. [source]


    The use of short-lived radionuclides to quantify transitional bed material transport in a regulated river

    EARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2007
    Nira L. Salant
    Abstract We investigate the use of the short-lived fallout radionuclide beryllium-7 (7Be; t1/2 = 53·4 days) as a tracer of medium and coarse sand (0·25,2 mm), which transitions between transport in suspension and as bed load, and evaluate the effects of impoundment on seasonal and spatial variations in bed sedimentation. We measure 7Be activities in approximately monthly samples from point bar and streambed sediments in one unregulated and one regulated stream. In the regulated stream our sampling spanned an array of flow and management conditions during the annual transition from flood control in the winter and early spring to run-of-the-river operation from late spring to autumn. Sediment stored behind the dam during the winter quickly became depleted in 7Be activity. This resulted in a pulse of ,dead' sediment released when the dam gates were opened in the spring which could be tracked as it moved downstream. Measured average sediment transport velocities (30,80 metres per day (m d,1)) exceed those typically reported for bulk bed load transport and are remarkably constant across varied flow regimes, possibly due to corresponding changes in bed sand fraction. Results also show that the length scale of the downstream impact of dam management on sediment transport is short (c. 1 km); beyond this distance the sediment trapped by the dam is replaced by new sediment from tributaries and other downstream sources. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Cannabis and crime: findings from a longitudinal study

    ADDICTION, Issue 1 2010
    Willy Pedersen
    ABSTRACT Aim To examine the association between cannabis use during adolescence and young adulthood, and subsequent criminal charges. Methods Data were obtained from the Young in Norway Longitudinal Study. A population-based sample (n = 1353) was followed from 13 to 27 years of age. Data were gathered on cannabis use, alcohol consumption and alcohol problems, and use of other illegal substances such as amphetamines, cocaine and opiates. In addition, extensive information on socio-demographic, family and personal factors was collected. This data set was linked to individual-level information from official Norwegian crime statistics. Findings We found robust associations between cannabis use and later registered criminal charges, both in adolescence and in young adulthood. These associations were adjusted for a range of confounding factors, such as family socio-economic background, parental support and monitoring, educational achievement and career, previous criminal charges, conduct problems and history of cohabitation and marriage. In separate models, we controlled for alcohol measures and for use of other illegal substances. After adjustment, we still found strong associations between cannabis use and later criminal charges. However, when eliminating all types of drug-specific charges from our models, we no longer observed any significant association with cannabis use. Conclusions The study suggests that cannabis use in adolescence and early adulthood may be associated with subsequent involvement in criminal activity. However, the bulk of this involvement seems to be related to various types of drug-specific crime. Thus, the association seems to rest on the fact that use, possession and distribution of drugs such as cannabis is illegal. The study strengthens concerns about the laws relating to the use, possession and distribution of cannabis. [source]


    Fundamental characteristics and 3D electromagnetic analysis for magnetic levitation transporter using YBCO superconductors

    ELECTRICAL ENGINEERING IN JAPAN, Issue 2 2007
    Hiroshi Ueda
    Abstract A magnetic levitation device with two-dimensional movement, the so-called "levitating X-Y transporter," has been developed. In order to develop a working levitating X-Y transporter, it is necessary to clarify the levitation characteristics, such as the lift force, levitation height, and stability against mechanical disturbances. In this paper, we examine the lift and the restoring force experimentally and propose a new simulation program based on the three-dimensional hybrid finite and boundary element method to analyze the dynamic behavior of electromagnetic characteristics of YBCO bulk. Using the numerical simulation and experiments, we investigated a suitable arrangement of permanent magnets to enhance the levitation characteristics. We also designed a levitating transporter which can carry a load of 200 kg with a gap of 16 mm. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(2): 44,54, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20220 [source]


    Nitrate-Selective Solid Contact Electrodes with Poly(3-octylthiophene) and Poly(aniline) as Ion-to-Electron Transducers Buffered with Electron-Ion-Exchanging Resin

    ELECTROANALYSIS, Issue 13-14 2006
    Galina
    Abstract The study of nitrate selective solid contact electrodes containing poly(3-octyl)thiophene and poly(aniline) demonstrated the advantage of buffering the transducing layer with electron-ion-exchanging resin. The buffering, in particular in the case of poly(aniline) doped with nitrate anions ensured significant improvement of the long-term stability and piece-to-piece reproducibility of the electrode potentials. It is shown that the redox species causes potential drift after a long time delay, probably because of slow diffusion in the membrane bulk. [source]