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Of Fields (of + field)

Distribution by Scientific Domains
Polymers and Materials Science50%

Kinds of Of Fields

  • variety of field
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    Selected Abstracts

    Microstructured Arrays of TiO2 Nanotubes for Improved Photo-Electrocatalysis and Mechanical Stability

    ADVANCED FUNCTIONAL MATERIALS, Issue 12 2009
    Daoai Wang
    Abstract The preparation of micropatterned TiO2 nanotubes (NTs) with tunable morphologies by combining laser micromachining technology and an anodization method is reported. The micropatterned structure can be easily designed and fabricated by laser micromachining a titanium substrate, further anodization of which gives nanotube arrays perpendicularly oriented to the titanium surface. The patterned TiO2 NTs show dramatically improved photocurrent and photocatalytic performances because of their enhanced surface area and light-harvesting capability. The photocurrent density and incident-photon-to-current efficiency at the peak absorption increases by 48 and 39%, respectively, compared to a TiO2 NT array without a patterned structure. It was also found that micropatterning dramatically improves the mechanical stability of the TiO2 NTs on the substrate, which otherwise were liable to peel off from the substrate surface. The strategy will reasonably expand the application of TiO2 NTs in a variety of fields that require enhanced photo-electrocatalysis and mechanical stability. [source]

    PRICE: primitive centred schemes for hyperbolic systems

    INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 12 2003
    E. F. Toro
    Abstract We present first- and higher-order non-oscillatory primitive (PRI) centred (CE) numerical schemes for solving systems of hyperbolic partial differential equations written in primitive (or non-conservative) form. Non-conservative systems arise in a variety of fields of application and they are adopted in that form for numerical convenience, or more importantly, because they do not posses a known conservative form; in the latter case there is no option but to apply non-conservative methods. In addition we have chosen a centred, as distinct from upwind, philosophy. This is because the systems we are ultimately interested in (e.g. mud flows, multiphase flows) are exceedingly complicated and the eigenstructure is difficult, or very costly or simply impossible to obtain. We derive six new basic schemes and then we study two ways of extending the most successful of these to produce second-order non-oscillatory methods. We have used the MUSCL-Hancock and the ADER approaches. In the ADER approach we have used two ways of dealing with linear reconstructions so as to avoid spurious oscillations: the ADER TVD scheme and ADER with ENO reconstruction. Extensive numerical experiments suggest that all the schemes are very satisfactory, with the ADER/ENO scheme being perhaps the most promising, first for dealing with source terms and secondly, because higher-order extensions (greater than two) are possible. Work currently in progress includes the application of some of these ideas to solve the mud flow equations. The schemes presented are generic and can be applied to any hyperbolic system in non-conservative form and for which solutions include smooth parts, contact discontinuities and weak shocks. The advantage of the schemes presented over upwind-based methods is simplicity and efficiency, and will be fully realized for hyperbolic systems in which the provision of upwind information is very costly or is not available. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    Gender and Negotiation: Some Experimental Findings from an International Negotiation Simulation1

    INTERNATIONAL STUDIES QUARTERLY, Issue 1 2009
    Mark A. Boyer
    Increasingly, scholars have taken note of the tendency for women to conceptualize issues such as security, peace, war, and the use of military force in different ways than their male counterparts. These divergent conceptualizations in turn affect the way women interact with the world around them and make decisions. Moreover, research across a variety of fields suggests that providing women a greater voice in international negotiations may bring a fresh outlook to dispute resolution. Using experimental data collected by the GlobalEd Project, this article provides substantial support for hypotheses positing that females generate significantly different processes and outcomes in a negotiation context. These findings occur both in terms of female negotiation behavior and the impact of females as negotiation facilitators/mediators. [source]

    Porous epoxies by reaction induced phase separation of removable alcohols: Control of spheroidal pore size by mass fraction, cure temperature, and reaction rate,

    JOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010
    Robert J. Klein
    Abstract Porous organic and inorganic materials with both random and controlled microstructures have utility in a variety of fields including catalysis, sensors, separations, optical platforms, tissue engineering, hydrogen storage, micro-electronics, medical diagnostics, as well as other applications. This work highlights a simple and general technique for tuning the pore size in crosslinking polymeric systems by adding a solvent poragen that phase separates during the curing process (reaction induced phase separation). The pore size can be controlled over large length scales ranging from microns to well below 100 nanometers. In this system an amine cured epoxy resin was reacted in the presence of the sacrificial poragen octadecanol, which is removed by vacuum-assisted evaporation once the epoxy components have reacted to form a solid, porous matrix. The importance of the present approach is based on the simplicity of the chemical formulation, the ease by which other epoxide or amine chemistries may be substituted for the two reactive components, and the control of pore size down to the nanometer scale by the addition of a small amount of catalyst. © 2010 Wiley Periodicals, Inc., J Appl Polym Sci, 2010 [source]

    Functional colloidal particles stabilized by layered silicate with hydrophilic face and hydrophobic polymer brushes

    JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 6 2009
    Yani Wu
    Abstract In this study, we describe a new strategy for producing narrowly dispersed functional colloidal particles stabilized by a nanocomposite with hydrophilic clay faces and hydrophobic polystyrene (PS) brushes on the edges. This method involves preparation of polymer brushes on the edges of clay layers and Pickering suspension polymerization of styrene in the presence of the nanocomposites. PS brushes on the edges of clay layers were prepared by atom transfer radical polymerization. X-ray diffraction and thermogravimetric analysis results indicated that PS chains were grafted to the edges of clay platelets. Transmission electron microscope results showed that different morphologies of clay-PS particles could be obtained in different solvents. In water, clay-PS particles aggregated together, in which PS chains collapsed forming nanosized hydrophobic domains and hydrophilic clay faces stayed in aqueous phase. In toluene, clay-PS particles formed face-to-face structure. Narrowly dispersed PS colloidal particles stabilized by clay-PS were prepared by suspension polymerization. Because of the negatively charged clay particles on the surface, the zeta potential of the PS colloidal particles was negative. Positively charged poly(2-vinyl pyridine) (P2VP) chains were adsorbed to the surface of PS colloidal particles in aqueous solution at a low pH value, and gold nanoparticles were prepared in P2VP brushes. Such colloidal particles may find important applications in a variety of fields including waterborne adhesives, paints, catalysis of chemical reactions, and protein separation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1535,1543, 2009 [source]

    Isolation and characterization of 15 microsatellite loci in the Korean goral (Nemorhaedus caudatus)

    MOLECULAR ECOLOGY RESOURCES, Issue 2 2005
    JUNGHWA AN
    Abstract Microsatellites have been applied in a variety of fields, including conservation genetics. Species-specific microsatellites are considered as more powerful genetic markers to generate an accurate genetic composition of a species itself. Accordingly, we characterized 15 polymorphic microsatellite loci from Korean goral, Nemorhaedus caudatus, one of the most endangered species in South Korea. The new markers should benefit future studies of the endangered species of other Asian gorals and their relatives for the study of genetic diversity and potential conservation management. [source]