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排序方式: 共有305条查询结果,搜索用时 15 毫秒
1.
Myung-Soon Lee 《Applied Surface Science》2006,252(14):5019-5025
We prepared high quality Au(1 1 1) film on Si wafer through the spin coating and thermal decomposition of a gold ink, spin-coated-and-fired (SCAF) Au film. The X-ray measurements, XRD and pole-figure analysis, showed that the SCAF Au film has a (1 1 1) out-of-plane orientation with a random in-plane orientation. In order to confirm the chemical activity of the SCAF Au film, we demonstrate the formation of patterned structures with the film by using soft lithography technique. The chemical activities of this physically stable SCAF Au film to the alkanethiols were at least equivalent those of physically deposited the Au films. The possibility of the mass production of micro patterned structure with the SCAF Au film was also demonstrated over the wide region on Si wafer by the microcontact lithography. These suggest that the Au film will help the easy fabrication of various nanosized devices on Si wafer and other substrates. 相似文献
2.
A new double pass long wavelength band erbium-doped fiber amplifier with enhanced noise figure characteristics is demonstrated. The noise figure is improved by about 2.6 dB with the incorporation of broadband conventional-band fiber Bragg grating (FBG) in between the two segments of erbium-doped fiber. By incorporating both the pre-amplifier and the FBG, the noise figure is further improved, which varies from 4.0 to 5.0 dB in the flat gain region from 1570 to 1600 nm. The gain varies from 32.0 to 33.4 dB within this region. The new amplifier with high gain and low noise figure can be useful as an inline amplifier in a wavelength division multiplexing transmission system. 相似文献
3.
4.
关于李萨如图形讨论的小结 总被引:4,自引:0,他引:4
对《大学物理》和其它一些刊物上多年来关于李萨如图形的讨论作了归纳和分析。 相似文献
5.
X-射线散射理论分析(FRS-XRSA)是作者为了研究和表征取向高聚物结晶度与晶粒取向分布(ODC)的一种新方案.在表征ODC方面应用分峰法(CPR)消除了传统极图法(PFM)中高重叠峰相互干扰的困难,克服了取向分布函数分析(ODFA)中出现虚织构的困难,并且经一次系统的FRS-XRS测定,可以得到几乎所有主要(hkl)晶面法向的ODC.作者应用FRS-XRSA对二类双轴取向PET磁带薄膜进行了ODC的研究。基于结晶几何学原理(CGP),建立了三斜晶系晶粒坐标系与试样坐标系的关系,并用于推演未测定方位角(αi,βi)(hkl)的晶面散射以及未测(h′k′l′)晶面的ODC.作者关系建立了双轴取向函数〈cos2φhkl,i〉,i=N、M、T的计算公式.按照FRS-XRSA获得了反映取向分布的10个晶面的双轴极图、三个主晶面(100)、(010)、(105)的总极图,以及反映平均取向的各种取向函数,如〈cos2φhkl,i〉、fchkl,i等,结果十分令人满意. 相似文献
6.
The dependent relation between temperature and pressure of supercritical CO2+ ethanol binary system under the pressure range from 5 to 10 MPa with the variety of densities and mole fractions of ethanol
that range from 0 to 2% was investigated by the static visual method in a constant volume. The critical temperature and pressure
were experimentally determined simultaneously. The PTρ figures at different ethanol contents were described based on the determined pressure and temperature data, from which pressure
of supercritical CO2 + ethanol binary system was found to increase linearly with the increasing temperature. P-T lines show certain convergent feature in a specific concentration of ethanol and the convergent points shift to the region
of higher temperature and pressure with the increasing ethanol compositions. Furthermore, the effect of density and ethanol
concentration on the critical point of CO2 + ethanol binary system was discussed in details. Critical points increase linearly with the increasing mole fraction of
ethanol in specific density and critical points change at different densities. The critical compressibility factors Zc of supercritical CO2 + ethanol binary systems at different compositions of ethanol were calculated and Z
c
-ρ figure was obtained accordingly. It was found from Z
c
-ρ figure that critical compressibility factors of supercritical CO2 unitary or binary systems decline linearly with the increasing density, by which the critical point can be predicted precisely. 相似文献
7.
Naoyuki Takahashi Arei Niwa Tadashi Takahashi Takato Nakamura 《Solid State Sciences》2003,5(11-12):1417-1419
The structural analysis of the hexagonal InN film prepared on a Si(100) substrate by the AP-HCVD technique using InCl3 and NH3 as starting materials were carried out by the X-ray pole figure analysis. The deposited films consist of the hexagonal InN pillar crystals. It was found that the pillar crystals, which have random rotation around the 100 axis, were grown at an angle of 70–90° to the substrate. 相似文献
8.
《中国物理 B》2021,30(5):57303-057303
A novel super-junction LDMOS with low resistance channel(LRC), named LRC-LDMOS based on the silicon-oninsulator(SOI) technology is proposed. The LRC is highly doped on the surface of the drift region, which can significantly reduce the specific on resistance(Ron,sp) in forward conduction. The charge compensation between the LRC, N-pillar,and P-pillar of the super-junction are adjusted to satisfy the charge balance, which can completely deplete the whole drift,thus the breakdown voltage(BV) is enhanced in reverse blocking. The three-dimensional(3 D) simulation results show that the BV and R_(on,sp) of the device can reach 253 V and 15.5 mΩ·cm~2, respectively, and the Baliga's figure of merit(FOM = BV~2/R_(on,sp)) of 4.1 MW/cm~2 is achieved, breaking through the silicon limit. 相似文献
9.
Soft Phonon Modes Leading to Ultralow Thermal Conductivity and High Thermoelectric Performance in AgCuTe 下载免费PDF全文
Subhajit Roychowdhury Manoj K. Jana Jaysree Pan Satya N. Guin Prof. Dirtha Sanyal Prof. Umesh V. Waghmare Prof. Kanishka Biswas 《Angewandte Chemie (International ed. in English)》2018,57(15):4043-4047
Crystalline solids with intrinsically low lattice thermal conductivity (κL) are crucial to realizing high‐performance thermoelectric (TE) materials. Herein, we show an ultralow κL of 0.35 Wm?1 K?1 in AgCuTe, which has a remarkable TE figure‐of‐merit, zT of 1.6 at 670 K when alloyed with 10 mol % Se. First‐principles DFT calculation reveals several soft phonon modes in its room‐temperature hexagonal phase, which are also evident from low‐temperature heat‐capacity measurement. These phonon modes, dominated by Ag vibrations, soften further with temperature giving a dynamic cation disorder and driving the superionic transition. Intrinsic factors cause an ultralow κL in the room‐temperature hexagonal phase, while the dynamic disorder of Ag/Cu cations leads to reduced phonon frequencies and mean free paths in the high‐temperature rocksalt phase. Despite the cation disorder at elevated temperatures, the crystalline conduits of the rigid anion sublattice give a high power factor. 相似文献
10.
在传统光学电流传感器技术的基础上,提出了一种四光路光学电流传感器,其通过四路输出信号可准确确定偏转角,使电流的测量范围不受正弦函数的单调性的限制,从而提高了电流的测量范围。配合四光路结构,提出了新的反正切函数数据处理方法,其不存在角度不灵敏区、可纠正原始数据的缺陷,从而提高了测量精度。实测了充电电压为4.5 kV、电容为50 μF和导线有效穿过磁光探头14次的快开快门的总短路电流,其峰值达85 kA,与理论值87 kA能较好地吻合,从而证明了四光路光学电流传感器可有效地测量脉冲大电流。 相似文献