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Semiconductors - In the present paper, analytical modeling of surface potential and drain current for hetero-dielectric double gate tunnel FET (HDG-TFET) has been done. The two dimensional (2D)...  相似文献   
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In the catalytic reaction of an iron(III) porphyrin with t-BuOOH, CumOOH, H2O2 and C6F5IO, cyclohexene was used as a probe substrate. The selective hydroxylation of cyclohexene by hydroperoxides proceeds through radical path and this has been utilized for successful dioxygen activation/autooxidation. For other oxidants epoxide was the major product and the reactions proceed through non-radical path.  相似文献   
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Summary The three-dimensional Poisson-Voronoi model, which is topologically equivalent to the microstructure of real ceramics and metals, has been used to study the stress distribution within a simulated polycrystalline aggregate having 200 grains. Micro-stresses such as the maximum principal stress, maximum shear stress, first invariant of stress, and Von-Mises stress are found to vary systematically with the anisotropy of single crystal.  相似文献   
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The oxygen-deficient phase of the highT c superconductor, YBa2Cu3O7, was oxygen-enriched using the fluidization technique to give good superconducting properties. The normal method of oxygen treatment at 900°C for 24 h and at 600°C for 24 h has been reduced to just one treatment at 600°C for 12 h by the fluidization technique to achieve almost the same strength of superconducting signal for the YBa2Cu3O7 powder, which establishes the attractiveness of the latter route for the large-scale preparation of superconducting material. The particle sizes were in the range 0–90, 90–180 and 180–420 μm. The fluidized particles were crystalline with orthorhombic distortion.T c onset , estimated using the a.c. magnetic susceptibility method, was 91·3 K. The volume fraction of superconducting material in the product was 83·7–85·3%, one of the highest values reported so far for YBa2Cu3O7.  相似文献   
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Mahapatra  R.N.  Varma  S.K.  Lei  C.  Agarwala  V.V. 《Oxidation of Metals》2004,62(1-2):93-102
The isothermal-oxidation behavior of Rh–30Ni–18Nb refractory alloy was investigated up to a period of 312 hours in air from 1000 to 1350°C. A comparison of the oxidation behavior of this alloy with a conventional Ni-base superalloy (Inconel 713 C) shows an order-of-magnitude higher oxidation resistance. This experimental alloy oxidizes by forming alternate layers of Nb2O5 and RhO while NiO is on the surface in contact with air. Optical and scanning-electron microscopy (SEM) was used to study the microstructure and morphology for the characterization of the oxides. Thermal stability of the alloy for extended periods of exposure to air at 1400°C was studied using transmission-electron microscopy (TEM).  相似文献   
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Growing interests in multi-criteria decision support applications have resulted in a flurry of efficient skyline algorithms. In practice, real-world decision support applications require to access data from disparate sources. Existing techniques define the skyline operation to work on a single set, and therefore, treat skylines as an “add-on” on top of a traditional Select-Project-Join query plan. In many real-world applications, the skyline dimensions can be anti-correlated such as the attribute pair {price, mileage} for cars and {price, distance} for hotels. Anti-correlated data are particularly challenging for skyline evaluation and therefore have commonly been ignored by existing techniques. In this work, we propose a robust execution framework called SKIN to evaluate skyline over joins. The salient features of SKIN are: (a) effective in reducing the two primary costs, namely the cost of generating the join results and the cost of dominance comparisons to compute the final skyline of join results, (b) shown to be robust for both skyline-friendly (independent and correlated) as well as skyline-unfriendly (anti-correlated) data distributions. SKIN is effective in exploiting the skyline knowledge in both local within individual data sources and across disparate sources—to significantly reduce the above-mentioned costs incurred during the evaluation of skyline over join. Our experimental study demonstrates the superiority of our proposed approach over state-of-the-art techniques to handle a wide variety of data distributions.  相似文献   
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Multimedia Tools and Applications - Leap motion sensor provides a new way of interaction with computers or mobile devices. With this sensor, users can write in air by moving palm or finger, thus,...  相似文献   
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