沟道作用

Discussion and analysis are presented about the origin of the mobility enhancement by channel orientation along with biaxial strain in this work.

讨论和分析了这种双轴应变和沟道方向改变的共同作用下迁移率增强的机理。

The effect of tribology factors on bearing vibration is studied experimentally. AR model and WPT are used to processing the normal arid abnormal signals. The results are as follows:1. The vibration of ball bearings is caused by the tribology action of contact pairs of ball and ring races and has the essential of tribo-dynamics. Any factors affecting the tribology characteristics of contact pairs will affect vibration and noise of bearings consequently.2. Vibration characteristics of bearing keep almostly unchanged with the increasing of axial load expecting the increasing of nature frequencies. When radial load increasing with axial load unchanged, nature frequencies keep unchanged but some new vibration peaks appears in the spectrum.3. Vibration amplitudes are damped and nature frequency are enhanced with sufficient lubrication. Vibration and noise of bearings increase obviously and roar can happen and the contact surfaces scratch slightly under insufficient and unclean lubrication state. Bearing will be disabled in a few minutes without any lubrication.4. Bearing vibration is unstable under low speed. With the speed increasing, the vibration become stable and natural frequencies increase slightly but the amplitudes increase apparently.5. Bearing vibration can be excited only by some harmonics ofwaviness without lubrication and by all harmonics with lubrication based on the theoretical analysis.6. The nature frequencies of ball bearings decrease with the increasing sizes. When international clearance increasing, nature frequencies decrease in radial and increase in axial and angular and the amplitudes increase in radial and decrease in axial and angular. When the number of balls increasing, nature frequencies increase and amplitudes decrease. When the pitch diameter increasing, axial nature frequency increase and others nearly keep no change. When outer race groove curvature radius increasing, nature frequencies increase in radial and decrease in axial and angular and amplitudes keep no change in radial and increase in axial and angular. When inner race groove curvature radius increasing, nature frequencies decrease and amplitudes increase.7. The distortion in amplitude and frequency components of bearing vibration signals picked up by the present probe measurement method is founded and right conclusions cannot be achieved by the signals. When accelerometer is rigidly screwed with steel stud onto a flat outer surface of a ball bearing, vibration signal can be got without distortion and the reliability of research on bearing vibration is assured.8. AR model is suitable for large samples of bearing vibration signals, square root of length of samples can be used as the upper limitation of order determination and the FPE order selection criterion is effective. Many advantages of AR spectrum are founded over the classical based on FFT.9. Time-Frequency analysis is necessary for abnormal noise of ball bearings. WPT overcomes the principle shortcomings of STFT and proved to be a best tool to process the abnormal signals.

理论分析和试验研究表明： 1球轴承振动是钢球—滚道接触副中的各种摩擦学作用引起的，具有摩擦动力学的本质，任何对接触副的摩擦学特性有影响的因素都将对球轴承的振动和噪声特性产生影响； 2中心轴向载荷作用下，载荷增大使球轴承的固有振动频率升高，载荷越大同样的载荷增幅引起的频率升幅减小，足够大的中心轴向载荷作用下载荷的变化对球轴承振动的频率特性不会产生明显的影响； 3轴向和径向联合载荷作用下，径向载荷不大时球轴承振动的固有频率基本不变，但是可能引起变刚度激励的非线性振动，出现新的频峰，过大的径向载荷将使部分钢球脱离接触，使球轴承的振动和噪声呈现不稳定状态； 4润滑对球轴承的振动和噪声特性有重要的影响，良好的润滑对振动有明显的抑制作用，润滑不充分时，振动和噪声的水平会有明显增高，一定条件下还会激发接触副中的谐振，发出啸声，造成接触表面的伤害，无润滑干接触时，短时的运转就会损伤接触副表面，使振动和噪声迅速增大，并随时可能引发严重的磨损和卡滞失效；接触副润滑良好时，油膜的"刚化效应"使球轴承振动的固有频率有所提高，润滑剂中含有弥散性污浊时，振动的幅度总体升高，但弥散性污浊不会改变球轴承振动的频率特性；浙江大学博士学位论文：球轴承振动的研究 5低速时，球轴承振动的基本特征呈现不稳定状态，随着转速的提高，球轴承振动的频率特性趋于稳定，固有频率频峰升高； 6理论分析表明，干接触时钢球和滚道表面波纹度的某些谐波分量能激励球轴承的振动，振动的幅值与谐波幅值成正比，实际球轴承中钢球的分布不可能完全均匀，波纹度的激励作用会随时发生；润滑接触的分析表明，波纹度的任意谐波分量均能激励球轴承的振动； 7球轴承的几何和结构参数分析表明，球轴承尺寸越大，径向、轴向和角振动的固有频率越低；钢球中心圆直径增大，球轴承的径向和轴向振动的固有频率基本不变，角振动的固有频率有所上升，振动的幅频特性基本不变；径向游隙加大使球轴承的径向振动固有频率降低，轴向和角振动的固有频率有所升高，径向振动幅频特性的幅值升高，而轴向和角向降低；钢球的数量增多使球轴承振动的固有频率上升，幅频特性的幅值下降，径向振动的幅值下降最为明显；外圈沟曲率半径系数增大使球轴承径向振动的固有频率升高，轴向和角振动的固有频率降低，径向幅频特性基本不变，轴向和角向幅频特性幅值升高；内圈沟曲率半径系数增大使径向、轴向和角振动固有频率均下降，振动幅频特性的幅值均有升高； 8试验对比表明，传感器采用探针式安装时，由于探针接触副接触特性的影响，钡(量得到的球轴承振动信号有失真，采用专门设计和制作的试验球轴承，以固定式安装加速度计，首次测量得到了球轴承振动的真实信号，通过对振动信号的分析，验证了球轴承振动的理论模型； 9)基于时间序列分析的AR模型适用于大样本球轴承振动信号的分析，以样本长度的均方根值作定阶上界，FPE做判阶准则，给出的AR谱光滑，频率分辨率高，是球轴承振动分析的简便而可靠的手段； 10以时频域分析的小波包变换分析球轴承异音信号能够比较好地定位和聚焦异音发生的时间，时间间隔，频率范围，同样是球轴承振动分析的可靠的手段，可用作球轴承故障诊断技术。

Based on the 2-D distribution of channel impurity, the distribution of 2-D electric field and 2-D interaction potential, which is caused by the interaction between the ionized impurity in the depletion layer and radiation induced positive spatial charge, is analyzed by using image charge method. Resolving Poisson equation, the mobility expression of N-type and P-type non-uniform channel MOS and the mathematics expression of the threshold voltage model of DMOS are obtained.

基于沟道杂质的非均匀分布，借助镜像法导出非均匀沟道辐照正空间电荷和沟道中电离杂质的二维场及其作用，给出非均匀沟道DMOS器件辐照正空间电荷与沟道杂质的二维互作用势。

Daorengou quartz monzonite is a syntectonic granitoid and its formation was related with the matching of continental rift.

道仁沟石英二长岩是同构造花岗质岩石，它的形成与大陆裂谷的拼合一碰撞作用相关。

The spectroscopic and morphology results show that NOMA could be rapidly and effectively adsorbed on the surface of SWNT without changing the native structure of NOMA and the structure properties of SWNT.

以NOMA-SWNT管束为导通沟道构建了碳纳米管场效应管器件，检测了麦芽糖和伴刀豆凝集素蛋白的特异性识别作用。

From the self-consistent solution of 2-D Poisson equation and Schrdinger equation,the electron states and pinch-off behavior in quantum well channel of GaN HFET under longitudinal and transversal electric field were investigated.

从自洽求解二维泊松方程和薛定谔方程出发，研究了纵、横向电场作用下GaNHFET沟道中的电子态和夹断特性。

Three basin prototype s are generated in the southeast of Junggar Basin: filling basin in the post-rift sequenceP_2-T_(2-3,foredeep basin in the post-rift sequenceT~~3__3-J_(1-2 and intracontinental foreland basin(J_3-E).

准噶尔盆地东南部发育了3套盆地原型，即P2—T2-3的后裂谷期充填盆地、T33—J1-2的裂谷后前渊盆地、J3—E的陆内前陆盆地的并列叠加作用；发育了3套主力生油岩系，即上二叠统芦草沟组、红雁池组和上三叠统黄山街组、郝家沟组及下、中侏罗统八道湾组、三工河组、西山窑组，并赋存于阜康凹陷、吉木萨尔凹陷、五彩湾凹陷、黄草湖凹陷之中，形成了多个供油中心。

Depending on intersecting channels and electro osmotic pumping, valveless switching of solvent flow is realized and the injection volume is 30 pL.

还描述了交叉点进样的方法，利用交叉形状的沟道和电场作用下的电渗流实现了溶液的无阀转换，进样体积为30pL

To exert the use of high sensitive CCD and improve the performance of instruments and the quality of pulsatile signal of spectrum,the paper based on linear CCD of buried channel IL-C6-2048C,the output of which is subtractive polarity and discrete analog signal,and intermixes the high amplitude of reset-pulse,designs the circuit to pre-treat properly to the output's signal.

为了充分发挥高灵敏度CCD的作用，提高脉动光谱信号的质量和仪器的性能，本文在埋沟道型IL-C6-2048C线阵CCD基础上，根据CCD的输出信号是负极性的离散模拟信号并且混杂有幅度较大的复位脉冲干扰的特点，设计电路对CCD输出信号进行适当的预处理。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了