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随着民办高等教育规模的不断扩大,青年教师正在迅速成为民办学校发展的骨干力量,他们的整体水平成为民办高校师资力量和教学质量的关键因素.该文通过对民办高校教师培养情况进行调查分析,找出培养过程中存在的问题,并提出相应对策.  相似文献   
2.
传统的隐马尔可夫模型的缺点在于不能很好地描述语音信号的动态特性。某些改进算法状态持续时间进行修正,但是也削弱了对实时信号长度变化的适应性。作者在传统的隐马尔夫模型的基础上,通过在引入状态持续时间时,将其归一化。并观察序列长度对它的影响,使之能较好地描述语音信号的动态特性,同时也能较好地自适应描述实时语音信号的长度变化。  相似文献   
3.
The optical quenching of photoconduetivity under dual illumination in GaN samples with different resistivity is investigated to reveal the variation of deep levels. The samples are grown by metal organic chemical vapour deposition without intentional doping. Quenching bands centered at 1.35 eV, 1.55 eV, 1.98eV, and 2.60 eV are observed. It is found that the 1.98eV quenching band is dominated in all the samples and the 2.60eV band is observed only in the high-resistivity samples. The possible defect levels responsible for the quenching bands and the origin of different quenching behaviour at 2.60eV are discussed. It is suggested that the defect level responsible for quenching at 2.60 eV plays an important role for the enhancement of resistivity.  相似文献   
4.
耀变体甚高能(E100GeV)辐射能谱由于TeV伽玛光子与河外星系背景光光子之间的相互作用而比Fermi-LAT所观测到的伽玛射线能谱更软。基于同步自康普顿模型和河外星系背景光模型,利用高能辐射探测器在GeV和TeV能段对耀变体源3C66A的观测结果,对其红移进行限制。  相似文献   
5.
王翠梅 《科技信息》2012,(32):221-221
由于医护专业培养对象的独特性,教学内容的专业性,医护技能的实践性等特点,医护学专业师资队伍在建设中不仅要满足曾规的师资队伍建设的要求,还要注重师德与医德相结合、理论基础与实践技能相结合、专职教师与兼职教师相结合,构建满足医护教学实际需要的教师队伍,保证教育教学质量。  相似文献   
6.
本文通过CIH病毒的加载过程,分析了Windows9x操作系统中存在的一些安全缺陷.并总结了Windows9x病毒可能具有的某些特性,对于查毒工作有一定实用价值  相似文献   
7.
Lateral Schottky barrier diodes (SBDs) on A1GaN/GaN heterojunctions are fabricated and studied. The characteristics of the fabricated SBDs with different Schottky contact diameters and different Schottky-Ohmic contact spacings are investigated. The breakdown voltage can be increased by either increasing the Schottky-Ohmie con- tact spacing or increasing the Schottky contact diameter. However, the specific on-resistance is increased at the same time. A high breakdown voltage of 1400 V and low reverse leakage current below 20nA are achieved by the device with a Schottky contact diameter of 100 μm and a contact spacing of 40 μm, yielding a high V^2BR/ RoN,sp value of 194 MW.cm^-2.  相似文献   
8.
AlGaN/GaN heterostructures have been irradiated by neutrons with different fluences and characterized by means of temperature-dependent Hall measurements and Micro-Raman scattering techniques. It is found that the carrier mobility of two-dimensional electron gas (2DEG) is very sensitive to neutrons. At a low fluence of 6.13 × 10^15 cm^-2, the carrier mobility drops sharply, while the sheet carrier density remains the same as that of an unirradiated sample. Moreover, even for a fluence of up to 3.66 × 10^16 cm^-2, the sheet carrier density shows only a slight drop. We attribute the degradation of the figure-of-merit (product of ns×μ ) of 2DEG to the defects induced by neutron irradiation. Raman measurements show that neutron irradiation does not yield obvious change to the strain state of AlGaN/GaN heterostructures, which proves that degradation of sheet carrier density has no relation to strain relaxation in the present study. The increase of the product of ns × μ of 2DEG during rapid thermal annealing processes at relatively high temperature has been attributed to the activation of GeGa transmuted from Ga and the recovery of displaced defects.  相似文献   
9.
Hydrogen Sensors Based on AlGaN/AlN/GaN Schottky Diodes   总被引:2,自引:0,他引:2       下载免费PDF全文
Pt/AlGaN/AlN/GaN Schottky diodes are fabricated and characterized for hydrogen sensing. The Pt Schottky contact and the Ti/Al/Ni/Au ohmic contact are formed by evaporation. Both the forward and reverse currents of the device increase greatly when exposed to hydrogen gas. A shift of 0.3 V at 300 K is obtained at a fixed forward current after switching from N2 to 10%H2+N2. The sensor responses under different concentrations from 50ppm H2 to 10%H2+N2 at 373K are investigated. Time dependences of the device forward current at 0.5 V forward bias in N2 and air atmosphere at 300 and 373K are compared. Oxygen in air azcelerates the desorption of the hydrogen and the recovery of the sensor. Finally, the decrease of the Schottky barrier height and sensitivity Of the sensor are calculated.  相似文献   
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