Direct 3D中聚光灯的设置

灯光可以让3D世界显得更真实。Direct 3D中有四种类型的灯光：环境光、定向光源、点光源和聚光灯。聚光灯是最复杂的一种灯光,其设置包括光源点位置、照射方向、照射范围等。本文介绍了聚光灯的相关属性,如何根据聚光灯发光的内、外锥角度计算其照射范围,并给出聚光灯设置的代码实现。由具体的实例验证前述计算方法,表现不同内、外锥角度参数值的设置对最终光照效果的影响。     

Dynamical process of cavitation bubble adsorbed in gold nanoparticle under combined irradiations of laser and ultrasound

Under combined irradiation of laser and ultrasound,cavitary bubbles are generated on the surface of gold nanoparticle.The laser-induced thermal effect,ultrasonic cavitation effect and the synergistic effect of laser and ultrasound are studied by means of the investigation of the dynamical process for the vibration of the cavitation bubble,with different external conditions such as laser power,ultrasound intensity,etc.It is found that dynamical process of the cavitation bubble can be modified by the irradiation of laser or ultrasound.The enhancement of laser power can increase the critical radius of the cavitation bubble,while that of ultrasound may intensify the vibration.Cavitation bubble may become more stable due to the synergistic effect of laser and ultrasound.It is also found that variation of the coupling between laser and ultrasound can affect synergistic effect.     

用混合劈尖测量水膜折射率

所谓"混合劈尖"是区别于单纯的空气劈尖和水膜劈尖的一种新型劈尖,即在劈尖角θ及有效长度L保持不变的情况下,在空气劈尖内人为地制造出水膜特区,形成一劈两区的布局.实验中同一光束的平行单色光垂直照射在该劈尖上,在两区域内不     

He-Ne激光照射对红细胞变化的研究

He-Ne激光对红细胞的作用至今尚有争论，有的认为He-Ne激光可引起周围血液和凝血系统的变化，提高血液中红细胞和血红蛋白的含量。1962年巴黎国际血液研究所报告：激光可以对红细胞造成损害，而对白细胞没有引起损害。     

Frequencies-Selected Enhancement of the Extended High-Order Harmonic Generation Plateau from a United Two-Atom System Irradiated by a Combined Pulse

We present a high-order harmonic generation (HHG) spectrum from a united two-atom system exposed to a combined laser pulse, by numerically solving a one-dimensional time-dependent Schr6dinger equation. The combined laser pulse is composed of a low-frequency femtosecond pulse and a high-frequency attosecond one with respective appropriate amplitudes. For a suitable inter-nuclear separation, the harmonic emission efficiencies near the second cutoff of the extended plateau can be effectively enhanced by more than four orders of magnitude compared with the case of the low-frequency pulse alone. Such a combined pulse irradiating on the united twoatom system ionizes each atom, in a large rate (but not to a too large ionization yield), mainly at a particular time-interval. When the ionized electron from an atom reaches at the vicinity of the other atom and recombines with it, significant HHG enhancement is achieved for particular harmonics. This result, to our knowledge, is one of the best up to now in the endeavor for dramatically extending the width and simultaneously enhancing the height of the plateau.     

电子束参量对轫致辐射照射量角分布的影响

本文研究了电子束半径,发射度及能量等参量对闪光X射线照射量在1m处角分布的影响。求得了使中心照射量最大,束半径与发射度之间应满足的拟合关系,表明了电子束能量越高,发射度越小,那么中心照射量就越大,照射量的空间分布就越理想。对电子细束入射位置和入射方向使用了解析法和随机抽样法求出,两种方法的数值计算所得的照射量分布符合得比较好。     

虚共焦腔选模及其在激光照射器上的应用

虚共焦腔具有极好的横模鉴别能力，可以实现基模输出，其模体积大而均匀，激光输出近场不烧孔，远场中心亮斑色全部能量的８４％，其发散角近于衍射极限，在照射器上尤为适用。     

利用星载照射器的双基地雷达

双基地雷达一直是倍受关注的雷达类型，因为它在防空上具有很多潜在的优点，人们对各种照射器-目标-接收机的几何结构进行了多年的探索和实践，其中有些采取了“栅栏”系统的形式探测穿越的目标；一些系统采用了“机会照射器”。“机会照射器”可以是现有的雷达（协作与非协作）或者是诸如通信和广播信号发射系统，尤其有前途的是基于电视传输的前向散射系统，跟踪目标是借助方位和多普勒频移信息而不是延时。此外，还利用DBS电视发射系统作为机会照射器，虽然受到诸如地球表面低功率密度信号的限制，但还是能显示其近距离探测能力。     

“神龙一号”轫致辐射靶设计

利用数值模拟方法,设计了"神龙一号"直线感应加速器的轫致辐射靶的靶材及结构。实验测量了钽叠靶所产生的X光照射量和X光焦斑,得到转换靶正前方1m处的X光照射量在0.103C/kg以上,产生的X光焦斑小于1.5mm,满足"神龙一号"轫致辐射靶的设计要求。