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排序方式: 共有515条查询结果,搜索用时 15 毫秒
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Wireless Personal Communications - A dual purpose system is presented in this paper which serves not only as a door closer, but is equally effective for surveillance purposes. The currently... 相似文献
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Microsystem Technologies - 相似文献
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Ferrite particles coated with biocompatible phases can be used for hyperthermia treatment of cancer. We have synthesized substituted
calcium hexaferrite, which is not stable on its own but is stabilized with small substitution of La. Hexaferrite of chemical
composition (CaO)0.75(La203)0.20(Fe2O3)6 was prepared using citrate gel method. Hydroxyapatite was prepared by precipitating it from aqueous solution of Ca(NO3)2 and (NH4)2HPO4 maintaining pH above 11. Four different methods were used for coating of hydroxyapatite on ferrite particles. SEM with EDX
and X-ray diffraction analysis shows clear evidence of coating of hydroxyapatite on ferrite particles. These coated ferrite
particles exhibited coercive field up to 2 kOe, which could be made useful for hysteresis heating in hyperthermia. Studies
by culturing BHK-21 cells and WBC over the samples show evidence of biocompatibility. SEM micrographs and cell counts give
clear indication of cell growth on the surface of the sample. Finally coated ferrite particle was implanted in Kasaulli mouse
to test its biocompatibility. The magnetic properties and biocompatibility studies show that these hydroxyapatite coated ferrites
could be useful for hyperthermia. 相似文献
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The optical transmission of Tl3 As Se3 as a function of wavelength and temperature is reported for the 1.2 – 2.5 um spectral range, and at temperatures from 40 to 300K. The absorption edge for the material occurs at about 1.011 eV. The material also indicated direct transitions at about 1.015 eV and indirect transitions at about 1.001 eV. The direct and indirect transitions are found to be independent of temperature. Electrical measurements have identified the sample as p-type, with hole concentrations of 5 × 1015 and 6 × 1012 cm?3 at 395 and 300K, respectively. The sample seems to be a good insulator at all temperatures between 40 ?300K. 相似文献
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In this report, the role of 34 kDa HA-binding protein in hyaluronic acid-induced cellular signalling in lymphocytes has been examined. The binding of 125I-HA to lymphocytes in vivo was found to be inhibited by pre-incubation of the cells with anti-34 kDa HA-binding protein antibodies, thus confirming 34 kDa HA-binding protein as the specific HA-receptor in lymphocytes. This observation was substantiated by anti-34 kDa HA-binding protein antibodies immunoblotting and 125I-HA ligand blotting of lymphocytes cell lysate. The HA-induced cell aggregation, tyrosine phosphorylation and cytoskeletal protein phosphorylation demonstrate the HA-induced early cellular signalling events in lymphocytes. Further, to study the involvement of 34 kDa HA-binding protein in mitogen induced lymphocyte signalling, we studied in vivo phosphorylation and secondary messenger formation. The enhanced 34 kDa HA-binding protein phosphorylation by HA and the inhibition of cellular aggregation and IP3 formation by anti-HA-binding protein antibodies revealed that 34 kDa HA-binding protein is one of the potential mediators in HA-induced signal transduction. 相似文献
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A. Deb P. K. Banerjee 《International journal for numerical methods in engineering》1989,28(7):1539-1555
A comparison between a family of isoparametric C°-continucus elements in the context of two-dimensional elastostatics using the direct boundary element method is presented. The elements studied use Lagrangian shape functions of orders quadratic, cubic and quartic. The relative efficiencies of these elements from the viewpoint of accuracy of solution as well as cost effectiveness are examined through certain selected problems. It emerges from the present study that the quartic element is more reliable in accuracy than the lower members of the family without being necessarily more expensive. 相似文献
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Arup Kumar Nandi Shubhabrata Datta Kalyanmoy Deb 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(6):989-1008
Polyurethane is used for making mould in soft tooling (ST) process for producing wax/plastic components. These wax components are later used as pattern in investment casting process. Due to low thermal conductivity of polyurethane, cooling time in ST process is long. To reduce the cooling time, thermal conductive fillers are incorporated into polyurethane to make composite mould material. However, addition of fillers affects various properties of the ST process, such as stiffness of the mould box, rendering flow-ability of melt mould material, etc. In the present work, multi-objective optimization of various conflicting objectives (namely maximization of equivalent thermal conductivity, minimization of effective modulus of elasticity, and minimization of equivalent viscosity) of composite material are conducted using evolutionary algorithms (EAs) in order to design particle-reinforced polyurethane composites by finding the optimal values of design parameters. The design parameters include volume fraction of filler content, size and shape factor of filler particle, etc. The Pareto-optimal front is targeted by solving the corresponding multi-objective problem using the NSGA-II procedure. Then, suitable multi-criterion decision-making techniques are employed to select one or a small set of the optimal solution(s) of design parameter(s) based on the higher level information of the ST process for industrial applications. Finally, the experimental study with a typical real industrial application demonstrates that the obtained optimal design parameters significantly reduce the cooling time in soft tooling process keeping other processing advantages. 相似文献