The Nature of Light and Twentieth Century Experimental Physics

In the popular literature of physics the electromagnetic field isoften treated as though it has an intrinsic particle nature. When thetheory is examined carefully, quantum theory only makes the weakerrequirement that the emission and absorption of light are restricted todiscrete amounts of energy. There are very few realizable experiments inoptics for which the classical Maxwell theory and the quantum theorymake a different prediction. I discuss some of these experiments with anemphasis on the distinction between what the experiments tell us aboutthe measurement process, and what they tell us about the nature of thelight field.     

NSRL-XAFS光束线弧矢聚焦双晶单色器设计

针对XAFS光束线能量动态扫描的实验特点，介绍了弧矢聚焦双晶单色器的物理设计：包括晶体光学结构、性能参数计算、晶体热载分析和弧矢弯曲原理．弧矢缩比选择为1：4．88，水平接收角由原来的1mrad拓宽到3mrad，在不改变基本配置的情况下，获得了样品上束癍缩小、光子通量高达半个量级以上的增益．     

Relationship between the partitioning properties of motoneuron recruitment and the needle feeling propagation

Histological and physiological studies indicated that most skeletal muscles can be divided into a series of relatively independent sub-volumes: "neuromuscular compartments" and the partitioning property of the muscle result in the localization of muscle reflex. In the present experiment we studied the recruitment properties of medial gastracnemius (MG) muscle motoneuron pool of decerebrate cat with two kinds of local mechanical stimulation: local stretch and acupuncture-like stimuli. The results indicate that: (ⅰ) there is an obvious property of localization of recruitment activity, only the MNs which innervate the stimulated compartment were recruited by weaker and shorter stimuli; (ⅱ) recruitment activity spread to those MNs which supply the adjacent and distal compartments during the strength of stimulation or duration of the stimulation was increased; and (ⅲ) the recruitment property of muscle activity elicited by the local mechanical stimulation is thought similar to that of "needle feeling" along the meridian pathway during stimulation of acupuncture point.     

非谐振多光子过程的原子压缩效应

考虑非谐振情况下的多光子跃迁过程,在ｋ≥ｒ⊥,ｒ∥的条件下,利用绝热近似方法,由线性Ｆｏｋｋｅｒ－Ｐｌａｎｃｋ方程导出此过程的原子压缩表示式。     

N-terminal of L protein of vesicular stomatitis virus contains a new signal sequence

The L protein (241kD) of vesicular stomatitis virus (VSV) is the most important snbnnit of the replication complex. The existence of specific localization signal in the L protein was investigated by making recombinant constructs expressing truncated mutants of the L protein fused to green fluorescent protein (GFP) in transient transfection assays. The chimeric genes encoding varied N-terminal of L and GFP gene were put under the control of T7 promoter or CMV promoter. The fusion proteins were transiently expressed in BHK-21, COS-7, CHO or Hep G2 cells. When more than 120 residues were deleted or only 96 residues were kept on the N-terminal, the fusion proteins were shown to be distributed throughout the cells, cytoplasm and nucleus under the confocal microscope. However, other chimeric proteins with 120 or more amino acids were dotted and distributed in the perinuclear regions. And the fusion protein with 96—120 aa has the similar distribution. A thirteen-residue peptide QGYSFLHEVDKEA (108—120) was identified as localization signal, whose function would be absolutely distributed with the deficiency of D or V. Our results show that there is an independent localizing signal in N-terminal domain of L protein of VSV and this functional signal is conserved in different cell lines.     

单光子发射断层成像散射解析模型的快速算法

为校正单光子发射断层成像(SPECT)中Compton散射的影响,对投影过程进行了解析建模计算。对相机参数进行预计算形成查找表,结合初始放射源活度和散射媒质分布计算得到投影中的原发光子和一次散射光子分布。用数论方法计算查找表中的高维数值积分,使计算速度提高。分别用解析建模方法和Monte-Carlo程序对均匀模型和胸腔模型进行投影计算,比较其相对误差、归一化方差和计算时间。结果表明:解析建模方法的精度与Monte-Carlo方法相当,而计算速度快8倍,可以满足临床需求。     

基于生物光敏蛋白细菌视紫红质膜的光子晶体管的模型

生物光色材料细菌视紫红质（ｂＲ）分子的光循环具有两个主要光活性态－基态Ｂ（５６８ｎｍ）和最稳中间态Ｍ（４１２ｎｍ）。用它们吸收带波长的光照射ｂＲ将分别引起分子的异构（Ｂ→Ｍ）和复构（Ｍ→Ｂ）光反应。本文首先研究了化学增强ｂＲ膜的互补调制饱和吸收，即多光束照射引起Ｂ、Ｍ各态粒子数比例变化，多光束之间互补调制输出光强。研究发现，当５６８ｎｍ和４１２ｎｍ双光束同时入射长Ｍ态寿命的ｂＲ膜时，存在阈值光强Ｉ     

光子扫描隧道显微镜的超衍射分辨的光子理论假说

光子扫描隧道显微镜（ＰｈｏｔｏｎＳｃａｎｎｉｎｇＴｕｎｎｅｌｉｎｇＭｉｃｒｏｓｃｏｐｅ，简称ＰＳＴＭ）的发明是在近场光学理论、全内反射理论、光纤技术、高灵敏度光电探测技术和计算机等获得重大进展的基础之上取得的，最近的研究结果表明其ＰＳＴＭ已实现１～３ｎｍ的超衍射极限的分辨率，如何解释ＰＳＴＭ能够获得如此高的超衍射极限分辨率？ＰＳＴＭ能获得的超衍射极限分辨率会是多少？本文提出一种关于ＰＳＴＭ的光子理论假说，这个假说是基于下面两个基本定律：１．光子不只是携带能量和光学信息的载体，也是具有一定空间尺寸的基本粒子２．当光子发生反射、折射、散射等时，仅改变它所携带的能量和光学信息，它的粒子尺寸并不改变，即ｐｈｏｔｏ＝常数．将上面两个基本定律应用于ＰＳＴＭ时，所谓“消逝场（ｅｖａｎｅｓｃｅｎｔｆｉｅｌｄ）”实际上乃是弱光子分布场，探测光纤尖端尺寸实际上相当于一个“门”，它控制着进入光纤的光子数量，通过一些计算，可获得如下几个结论：１．在ＰＳＴＭ的探测系统足够灵敏的条件下，探测光纤尖端的直径Ｄ和近场探测间距Ｚ是决定ＰＳＴＭ超级射分辨率的两个最重要的因索．２．ＰＳＴＭ分辨极限将产生在Ｄ＝ｐｈｏｔｏｎ和Ｚ＝ｐｈｏｔｏｎ．３Ｐ     

依赖强度耦合JC模型的原子动力学

本文研究了依赖强度耦合ＪＣ模型中二能级原子的动力学行为，着重讨论了初始光场分别为Ｇｌａｕｂｅｒ相干态和ＳＵ（１，１）相干态时原子初态、失谐量以及平均光子数对原子反转的影响。