激光

The pulsed Nd:YAG laser cladding is one of the most effective methods of the precise repairing technology. It is decided by the voltage, electric current, pulse length, pulse frequency, scanning speed and beam diameter of the Nd:YAG laser.

脉冲Nd：YAG激光熔覆技术是精密修复塑料模具最有效的方法之一，激光器的电压、电流、脉冲宽度、脉冲频率与激光的扫描速度、光斑直径等工艺参数直接影响着熔覆的质量。

Femtosecond lasers have two charact er istics: ultrashort pulse length and ultrahigh electric field.

飞秒激光是近年来获得迅速发展的一种超快激光。超短脉冲和超高电场强度是它的两个特征。

Through analysis for the performance features of laser crystal end-pumped by a diode laser, a quadrate laser crystal thermal model is established.

通过对二极管激光器端面抽运激光晶体工作特点的分析，提出了长方形激光晶体热模型。

Continuous wave and quasi continuous wave Tm: Ho: GdVO4 solid laser at 2.049 μm using laser-diode double-end pumping is reported.

报道了激光二极管双端面抽运Tm： Ho： GdVO4固体激光器，在2.049 μm处获得连续和准连续激光输出。

Laser ultrasonic technique is a new technique that absorbs high-energy laser radiancy making use of metal surface, so, material is quickly heated, generate oscillation and generate ultrasonic pulse. The principle of actuating ultrasonic pulse has two kinds of elasticity actuating and ablation actuating.

激光超声技术是利用金属表面吸收高能激光辐射，引起材料快速加热，产生振动，发出超声脉冲的一种新技术，其激励超声脉冲机理有弹性激励和热烧蚀激励二种。

Based on the relation between the attenuation ratio and the transmittance of the laser, the variation of the attenuation of 10.6μm laser traveling in advection fog or radiation fog with the visibility and the FOV of the laser receiver is given.

最后，以工作波长为10.6μm的激光为例，利用衰减率与透过率之间的关系，给出了平流雾及辐射雾中激光雾衰减随能见度、接收器视场角等的变化关系。

The laser generated ultrasonic pulse method gives the Young′s modulus in the draw and transverse direction,while the pulsed photothermal radiometry method gives the thermal conductivity in the draw,transverse and thickness direction of the film.

应用激光脉冲热致超声法给出材料拉伸方向和横向杨氏模量，应用激光脉冲光热辐射法给出拉伸方向，横向和厚度方向的导热系数。

But internal reflections an the boundaries of active medium can drastically enhance the onset of ASE, particularly if these reflections lead to a close path, i.e., a ray that is reflected upon itself. In the case, we have a strong feedback mechanism and as soon as the gain in the laser medium exceeds the reflection losses parasitic oscillations will set in.

但自发辐射的存在使得放大器工作介质会在信号光到达前开始发射激光，并且工作介质边缘的内反射能显著增大ASE的发射，尤其当这些反射能导致产生封闭路径时更是这样，当激光介质内的增益超过损耗时，就建立起寄生振荡。

The bioceramic coating was made by Lasser remelt pretreating a layer of mixed powder CaHPO 4·2H 2O CaCO 3 Y 2O 3 on the TC 4 substrate.

在激光表面重溶预处理的TC4合金基材上预置涂敷CaHPO42H2O－CaCO3－Y2O3混合粉末，再经激光熔覆处理制备了生物陶瓷复合涂层。

Results The recovery rate of study group and control group is80%and60%respectively;the reoccurrence rate is20%and43.3%respectively.

结果 中西药激光组30例30眼与西药激光组30例30眼比较，其治愈率分别是80%、60%，2年复发率控制分别 20%、43.3%。

By the time of its fall, most of the prisoners were writers who had written against the corruptions of the government.

到它被攻陷的时候，里面多数的犯人是写了反对政府贪污文章的作家。

The most obvious variation to ovum morphological character was that the color was changed from light green to sepiaceous in embryonic development, and all the ovums were almost hatched after 96h.

在胚胎发育过程中卵的形态特征最明显的变化是颜色从淡绿到深褐色，卵在发育96h后卵基本全部孵化。