反转

The population inversion between the upper and lower lasing levels is considered as a necessary condition of lasing.

激光上能级和激光下能级间的粒子数反转通常被认为是实现激光振荡的必要条件。

In Chapter 3, we studied the effect of the driving field phase-fluctuation the open four-level non-inversion lasing system.

第四章在不考虑Doppler效应和考虑Doppler效应两种情况下，对开放的四能级无中文摘要反转激光系统受传播效应的影响的研究。

The transmission ratio exceeded 95% in near-infrared range, so the LCAS:Tm(superscript 3+) glasses can be used as high transmission optical glasses. The integral emission cross-sections outclassed 10^(-18)cm, the fluorescent ratios were higher and the radiative lifetimes were lenger, to the glasses are possible to be used as new laser function materials. The new strong and broad emissive bands for 400nm to 680nm emerge in the emission spectra of the another glasses samples.

高达95%以上近红外透过率表明，LCAS：Tm(上标 3+)玻璃可作为近红外波段高透过率光学玻璃；远大于10^(-18)cm的积分发射截面、较高的荧光分支比与能形成粒子数反转的荧光寿命表明，LCAS：Tm(上标 3+)玻璃可能成为一种新的激光功能材料。

The basic principle, advantages and disadvantages of the II were summarized. Computer-generated II based on 3DS MAX was proposed. The captures of three-dimensional information for II using 3DS MAX simulation and the display of three-dimensional information using an experiment assembly composed of a display screen and Fresel lens arrays were realized, respectively. The combination of the simulation and experiment resolved the flipping and crosstalk in conventional II.

介绍了集成成像技术的基本原理及其优缺点，提出了一种基于三维设计和动画制作软件3DS MAX的II技术，利用3DS MAX来实现II的三维信息的记录，利用显示器和菲涅尔微透镜阵列组成的实验装置实现II的三维信息的重现，解决了常规II技术存在的空间反转和串扰问题，从而研制出基于II技术的原理性裸眼三维显示器。

As more and more HI-infected South Africans access life-prolonging antiretroiral treatment, the question of whether or not to hae a child, and how to do so as safely as possible, is bound to become more common.

随着越来越到HI感染的南非人获得终身抗反转录病毒治疗，是否生育、如何安全生育这类问题变得越来越普遍。

Based on the theoretical model coupling Maxwells equation with the rate equation of 4 level inverted population, the numerical simulation is made via the FDTD method and MATLAB programs. The simulation results show that 1. With the increase of the pumping rate, both the localization of the electric field and the spectrum mode numbers will change; 2. The lasing threshold decreases by increasing the size or concentration of the scatters; 3. The lasing threshold also decreases by increasing the size of samples or strengthening the sample randomness.

在理论和实验研究的基础上，利用麦克斯韦方程与四能级反转粒子数的速率方程相耦合的理论模型，采用时域有限差分方法和MATLAB程序对随机激光泵浦阈值特性进行了数值模拟与计算，模拟结果显示：随着泵浦速率的增大，出现了阈值前后电场强度局域态及频谱模式数的改变；随着散射体粒径的增大，浓度的增大，阈值呈现下降的趋势；随着样品长度的增大，随机强度的增强，阈值也呈现下降的趋势。

A new regime of plasma-electrode Pockels cell operation for the laser megajoules project .

用于多程放大系统光束反转器的等离子体电极电光开关。

Using the total RNA of merozoites of Eimeria acervulina isolated from Guangdong Pro- vince as template,a partial segment of 3-1E gene was amplified by RT-PCR. The gene fragment 682 bp inlength was cloned into pGEM-T Easy vector,and the recombinant plasmid was identified by PCR,restric-tion enzyme analysis and sequencing. The homology analysis revealed that the nucleotide homology be-tween the 3-1E gene of the E.

根据GenBank中登录的堆型艾美球虫3-1E基因序列，设计了3条引物，以广东株堆型艾美球虫裂殖子总RNA为模板，利用反转录-聚合酶链反应扩增获得了3-1E基因部分片段，将这一片段克隆至pGEM-T Easy载体中，经PCR、限制性内切酶分析和克隆片段的序列测定、比较，证实了克隆片段的可靠性。

Dispersion compensation by mid-span spectral inversion can be achieved through FWM in semiconductor optical amplifier .

利用半导体光放大器中的四波混频效应可实现中点谱反转色散补偿。

53 myopia student were divided into 3 group based on the following classification: onset myopes (n=14), progressing myopes (n=23), stable myopes (n=16). accommodative facility measurements were taken for a 40-cm distance with +2.00 /-2.00Ds.

对53名近视学生按近视不同阶段分组：初发近视Ⅰ组14名、进展性近视Ⅱ组23名、稳定性近视Ⅲ组16名，采用±2.0Ds反转拍进行一分钟调节灵敏度值测定，并将结果进行相关统计分析。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。