雪崩

The plasma ignition threshold of metal is got through experimental and numerical study. The vapour and plasma ignition times of the target are got based on the equation of heat conduction and cascade model. We suppose that the plasma is ignited when generations of new electrons are born in vapour generation time. The influence of temperature on the thermodynamics and optics parameters of material also have been considered in the model. The resulting theory has good agreement with the experiment and overseas report. A blade method to measure the laser spot is given in this paper with validation and error analysis. The plasma threshold of metals in atmosphere and water ambients both are diagnosed with the light deflection and piezoelectric transducer. A Q-switched pulsed Nd:YAG laser operating at infrared (1064nm), visible(532nm) and ultraviolet (355nm) wavelengths has been used. Al、Fe、Cu are used as targets and get a similar results with both method. Theoretical and experimental analyses are applied on the influence of wavelength on the threshold have been done, both of which have shown that the plasma threshold of metals decrease as the laser wavelength increases; The plasma threshold of metals are higher in water than in air and the pressure of the shock wave in water is five times higher than in air .

从热传导方程和雪崩电离机制出发，假设当电子增值210倍时，考虑了温度对材料热力学和光学参数的影响时，得到了气化和等离子体点燃的时间，利用该模型进行计算得到的结果与国内外报道及自行通过实验测得的阈值基本一致；提出了利用刀刃法测量激光光斑面积的方法，并通过实验进行了验证和误差分析；利用光偏转装置和压电换能器分别对空气和水中金属等离子体点燃阈值进行了实验诊断，激光器均为调Q－YAG激光器（波长1064nm，532nm，355nm，脉宽10ns），靶材分别为Al、Fe和Cu，两种测试方法得到的等离子体点燃阈值基本一致；本文从实验和理论计算两个方面讨论了波长对等离子体点燃阈值的影响，均得到了等离子体点燃阈值随著波长的增加而减小的结论；对空气中和水中不同环境下金属等离子体的点燃阈值进行了比较研究，得到了金属在水中的等离子体点燃阈值比空气中的大，且水中产生的冲击波的压强是空气中的5倍左右的结论。

When you're a kid, boners are like Starbucks: they can pop up anywhere, at any time, and there's absolutely nothing you can do about it.

小时候，性兴奋就像星巴克一样，随时随地都会突然出现，而你却对它无能为力。像雪崩球一样，一阵微风吹过你都会兴奋。

An avalanche happened in Alps of Austria has caused 6 Czech mountain claimers dead.

发生在奥地利阿尔卑斯山脉的一场雪崩造成6名来自捷克共和国的登山者死亡。

Thus, before the stormy dawn, close to cloughs and bluffs, a combat and confrontation of love and hatred, life and death is being triggered between Professor Rubek, Mrs. Maia Rubek, Irene and Ulfheim a land proprietor

于是，在高山峭壁间，在雪崩袭来前，在鲁贝克、艾琳、梅雅和猎人

Glaciers and their immediate environs present many dangers for humans, such as crevasses and glacier mills into which one might fall, heavily crevassed ice falls, snow and ice avalanches from the side walls and, along the flanks, dumping of great boulders, ponding and floods from melt water.

冰川及其周边事物给人们带来众多威胁，比如冰隙（冰川插进来可能会造成崩塌）、冰瀑的严重裂缝、沿着边缘的侧墙发生的雪崩或冰崩、大块砾石的滚落、积水以及融水的泛滥。

Farmhouses and buildings were swept away in the avalanche .

雪崩夷平了农场的房子和其他建筑物。

Others have pulled half-buried avalanche victims from otherwise certain death, while the ice cracks beneath their canine feet.

别人拉半埋雪崩受害者，否则某些死亡，而冰缝下方其犬英尺。

Single PIN diode operates at a hold-off voltage exceeding 2.2 kV, and the time rate of voltage is promoted from 0.95 kV/ns to 1.37 kV/ns.

图 1 给出的是一个具有代表性的DBD器件结构，它是具有三层结构的硅雪崩二极管[2]。

Stacked PIN diodes in parallel and series operate at a hold-off voltage of 8.0 kV,and the dV/dt is promoted from 2.4 kV/ns to 3.2 kV/ns. Delayed breakdown device ; PIN diode ; Delayed breakdown

因此在输入脉冲 dV/dt很快的情况下，二极管会产生很高的过压，这时空间电荷区的电场强度远远大于雪崩击穿的临界场强，电子和空穴的电离率非常高，导致二极管在很短的时间内击穿，这个现象被

It also requires less load capability of high-voltage pulse power supply, and allows using avalanche transistor or MOS transistor to replace expensive krytron and unstable spark gap. That has simplified the whole system and improved reliability, stability and flexibility.

降低了对脉冲高压驱动电源负载能力的要求，允许用雪崩管或MOS管代替极其昂贵的冷阴极管和稳定性差的高压火花隙，提高了可靠性和稳定性，简化了系统，增加了灵活性。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。