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231.
Ab-initio calculations are performed to investigate the structural, electronic and magnetic properties of spin-polarized diluted magnetic semiconductors composed of II-VI compounds Cd1−xCoxX (X=S, Se, Te) at x=0.25. From the calculated results of band structure and density of states, the half-metallic character and stability of ferromagnetic state for Cd1−xCoxS, Cd1−xCoxSe and Cd1−xCoxTe alloys are determined. It is found that the tetrahedral crystal field gives rise to triple degeneracy t2g and double degeneracy eg. Furthermore, we predict the values of spin-exchange splitting energies Δx(d) and Δx(pd) and exchange constants N0α and N0β produced by the Co 3d states. Calculated total magnetic moments and the robustness of half-metallicity of Cd1−xCoxX (X=S, Se, Te) with respect to the variation in lattice parameters are also discussed. We also extend our calculations to x=0.50, 0.75 for S compounds in order to observe the change due to increase in Co.  相似文献   
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Solid polymer electrolyte (SPE) films based on poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF–HFP) with salt and ionic-liquid (IL) are synthesized using the solution-cast technique and summarized in this review. Doping ILs or salts increases ionic conductivity up to the device level. This is further confirmed using differential scanning calorimetry (DSC) and X-ray diffraction (XRD) measurements. Polarized optical microscopy (POM) affirms that enhancement in ionic conductivity is due to increase in amorphous nature of film. The complex nature of polymer electrolyte films is confirmed using Fourier transform infrared (FT-IR) spectroscopy. Overall results show that doping IL into polyether matrix is advantageous material playing a dominant role in electrochemical devices.  相似文献   
235.
Microfluidic devices for dielectrophoretic cell separation are typically designed and constructed using microfabrication methods in a clean room, requiring time and expense. In this paper, we describe a novel alternative approach to microfluidic device manufacture, using chips cut from conductor–insulator laminates using a cutter plotter. This allows the manufacture of microchannel devices with micron-scale electrodes along every wall. Fabrication uses a conventional desktop cutter plotter, and requires no chemicals, masks or clean-room access; functional fluidic devices can be designed and constructed within a couple of hours at negligible cost. As an example, we demonstrate the construction of a continuous dielectrophoretic cell separator capable of enriching yeast cells to 80% purity at 10 000 cells/s.  相似文献   
236.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   
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