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排序方式: 共有220条查询结果,搜索用时 15 毫秒
81.
Sergiy Korablov Kazunori Yokosawa Taku Sasaki Dmytro Korablov Akira Kawasaki Koji Ioku Emile H. Ishida Nakamichi Yamasaki 《Journal of Materials Science》2007,42(18):7939-7949
Hydrothermal growth of diamond particles and films was achieved during interaction of a liquid organic precursor (C2H3Cl3) and 10 M NaOH in the presence of diamond or cubic BN seeds at the temperature 300 °C and 1 GPa pressure. Synthesized diamond
was thoroughly characterized by TG-DTA, SEM, EDX, TEM, Raman spectroscopy and had (220) preferable orientation according to
XRD pattern in the case of the film. 相似文献
82.
Minko A. Hoel V. Morvan E. Grimbert B. Soltani A. Delos E. Ducatteau D. Gaquiere C. Theron D. De Jaeger J.C. Lahreche H. Wedzikowski L. Langer R. Bove P. 《Electron Device Letters, IEEE》2004,25(7):453-455
AlGaN-GaN high electron mobility transistors (HEMTs) on silicon substrate are fabricated. The device with a gate length of 0.3-/spl mu/m and a total gate periphery of 300 /spl mu/m, exhibits a maximum drain current density of 925 mA/mm at V/sub GS/=0 V and V/sub DS/=5 V with an extrinsic transconductance (g/sub m/) of about 250 mS/mm. At 10 GHz, an output power density of 1.9 W/mm associated to a power-added efficiency of 18% and a linear gain of 16 dB are achieved at a drain bias of 30 V. To our knowledge, these power results represent the highest output power density ever reported at this frequency on GaN HEMT grown on silicon substrates. 相似文献
83.
We consider a network representation of the stock market data referred to as the market graph, which is constructed by calculating cross-correlations between pairs of stocks based on the opening prices data over a certain period of time. We study the evolution of the structural properties of the market graph over time and draw conclusions regarding the dynamics of the stock market development based on the interpretation of the obtained results. 相似文献
84.
P. Pouillen R. Minko M. Verniette P. Martinet A.M. Martre 《Electrochimica acta》1979,24(11):1189-1194
The electrochemical bromination of cyclohexene has been studied in several solvents : acetonitrile, dimethylformamide, dimethylsulfoxide and methanol.In the former three solvents, the first oxidation step of the bromide ion is not modified by the cyclohexene presence, whereas the intensity of the second step depends on the amount of the added cyclohexene. In these three solvents, the oxidation current leads to same value when cyclohexene concentration increases. In methanol, the intensity of the single oxidation step of the Br? ion increases with the cyclohexene concentration.The preparative electrolyses were realised at the different oxidation steps of Br?. In acetonitrile only the trans-dibromo compound is formed. In the other solvents beside the 1,2-dibromo cyclohexane, bifunctional compounds are isolated; the solvent participation in the reaction is thus proved. 相似文献
85.
Benoit N Schröder S Yulin S Feigl T Duparré A Kaiser N Tünnermann A 《Applied optics》2008,47(19):3455-3462
The extreme-ultraviolet (EUV)-induced oxidation of Mo/Si multilayer mirrors was characterized by several methods: EUV reflectivity, x-ray photoelectron spectroscopy, small-angle x-ray reflectometry, atomic force microscopy, and EUV scattering measurements. Based on the results of the different investigation techniques, an oxidation model was developed to explain the degradation of the mirrors under EUV radiation. 相似文献
86.
Ralph Rosenbaum Sergiy Balanetskyy Benjamin Grushko Bartosz Przepiórzyński 《Journal of Low Temperature Physics》2008,150(1-2):82-100
Electrical resistivities of two icosahedral (I) Al-Pd-Re alloys have been measured between room temperature and mK temperatures.
One quasicrystalline (QC) polygrain Al-Pd-Re sample exhibited insulating behavior in its resistivities, increasing by a factor of r=R(4 K)/R(300 K)=7.76; its room temperature resistivity was 9,890 μΩ cm. A “phenomenological” expression fitted the conductivity data
well between 300 K to 0.5 K. Below 0.4 K a crossover to an activated variable-range hopping law was observed. Low temperature
magnetoresistance ratio data and fits using the wave function shrinkage theory are presented. A second QC Al-Pd-Re sample
had a small resistance temperature ratio r=2.12. The room temperature resistivity was extremely large, ρ(300 K)≈40,980 μΩ cm. Its conductivity could be described well using a simple temperature power law between 300 K to 20 K.
Below 20 K there was a crossover to a new behavior. Below 1 K, the conductivity could be fitted using a very weakly insulating
power law where σ(T)≈11.37T
0.032 in (Ω cm)−1, suggesting that this sample is located just below the metal-insulator transition. The magnetoconductivity data could not
be fitted successfully using the 3D weak localization (WL) theory and inserting into it physical and realistic fitting magnitudes
for the inelastic magnetic field B
in.
相似文献
87.
88.
89.
Lapchuk AS Shylo SA Nevirkovets IP 《Journal of the Optical Society of America. A, Optics, image science, and vision》2008,25(7):1535-1540
A local plasmon resonance on a metal wedge is studied by using the Meixner approach [J. Meixner, IEEE Trans. Antennas Propag.AP-20, 442 (1972)]. It is found that the singular field behavior of a local plasmon resonance as a function of the distance from the edge of the wedge is sensitive to the wavelength and wedge angle, and ranges from a dramatic increase in amplitude close to its theoretical limit to pure oscillatory behavior with only minor amplitude variation. Field singularities for gold, silver, and aluminum wedges are calculated. It is shown that, unlike an ideal-conductor wedge, the real part of the power index of the electric field singularity does not decrease monotonically as a function of the wedge angle, but has a minimum for some angle depending on the wavelength and material parameters. If the dielectric surrounding the wedge has a positive permittivity equal to the absolute value of that of the metal, and hence satisfies the plasmon resonance condition, then the electric field has a peculiar behavior for a wedge whose shape is close to the flat surface. 相似文献
90.
摘译 墨滴在纸页结构中的渗吸是一个非常复杂的过程.纸页中的孔隙以纳米级尺寸存在于纤维(纤维之间或几微米的大孔径)及其细胞壁中.墨滴的渗吸过程包括纤维间孔隙的毛细管作用、在纤维内部和细胞壁微孔中的渗透,以及沿纤维的表面扩散.喷墨墨滴大小只达到皮升级,因此纤维的芯吸效应和墨水在纤维表面的扩散起主要作用. 相似文献