Structure, Stability and Vibrational Spectra of LaC_5~n(n=-1,0,+1) Clusters

用密度泛含方法研究了ＬａＣ５ｎ（ｎ＝－１，０，＋１）分子簇的结构和稳定性及振动光谱，对这个六原子体系提出了三种可能构型，点群结构为Ｃ２ｖ对称性．第一个构型为Ｌａ接在弯曲的Ｃ５链上，第二个是Ｌａ通过二个键与Ｃ５环相连第三个是Ｌａ通过一个键与Ｃ５环相连；结果表明，第一个构型即当Ｌａ接在弯曲的Ｃ５链上时能量最低．振动光谱分析指出，当ｎ＝－１时，第二个构型为局域极小值；当ｎ＝＋１时，第一个和第二个构型为局域极小值；对ｎ＝０，局域极小值没有找到．     

对氟苯酚-过氧化氢-辣根过氧化物酶体系酶联荧光免疫分析研究──Ⅰ.对氟苯酚直接法及铝-钙指示剂偶合法测定人血清中乙肝表面抗原和表面抗体

对氟苯酚在辣根过氧化物酶（HRP）的催化下可被H2O2氧化，生成本酚及F-。测定对氟苯酚荧光猝灭程度及用铝－钙指示剂荧光体系检测酶促反应释放的F－，可分别建立HRP及其标记物的两种分析方法。铝－钙指示剂偶合法测定HRP的线性范围为0．031～31U／L，检测限（3δ）为0．0093U／L。两种方法分别用于测定人血清中乙肝表面抗原及抗体，结果令人满意。     

LaC_3~n(n=-1,0,+1)分子簇的理论研究(英文)

用密度泛函方法研究了ＬａＣ３ｎ（ｎ＝－１，０，＋１）分子簇的结构和稳定性，对这个四原子体系，提出了５种可能构型，其中３种具有Ｃ２ｖ对称性，２种为Ｃ∞ｖ对称性．在Ｃ２ｖ对称性结构中，其中１个为Ｌａ接在弯曲的Ｃ３链上，第２个是Ｌａ通过２个键与Ｃ３环相链，第３个是Ｌａ通过１个键与Ｃ３环相连；在Ｃ∞ｖ对称性中，第１个Ｌａ接在Ｃ３链的一端，而在第２个构型中，Ｌａ被插入在Ｃ３链中．结果表明，环状结构当Ｌａ接在弯曲的Ｃ３链上的是局域极小值并且最稳定     

硼原子的键合形式对硼酸盐晶体非线性光学行为的影响

在几种具有典型复杂结构的硼酸盐晶体中 ,从硼原子的键合形式出发讨论了不同键合情况下的B—O键对硼酸盐晶体的非线性光学行为的具体影响。结果表明 ,晶体中B—O键的键合形式是制约硼酸盐晶体非线性光学行为的重要因素。     

Rapid optimization of working parameters of microwave-driven multilevel qubits for minimal gate leakage

We propose an effective method to optimize the working parameters (WPs) of microwave-driven quantum gates implemented with multilevel qubits. We show that by treating transitions between each pair of levels independently, intrinsic gate errors due primarily to population leakage to undesired states can be determined by spectroscopic properties of the qubits and minimized by choosing proper WPs. The validity and efficiency of the approach are demonstrated by applying it to optimize the WPs of two coupled rf SQUID flux qubits for controlled-not operation. The result of this independent transition approximation (ITA) is in good agreement with that of dynamic method (DM). The ratio of the speed of ITA to that of DM scales exponentially as 2(n) when the number of qubits n increases.     

磁性阳离子交换树脂的结构与性能分析

利用古埃磁天平法、扫描电镜、粉末Ｘ射线衍射以及分光光度法等检测了化学转化法制备的磁性阳离子交换树脂。结果表明,所制备的树脂内部磁性物质为Ｆｅ３Ｏ４,且在 树脂内部的孔道及表面分布均匀,均被封锁在树脂内部,因而,这类磁性树脂在碱性和中性盐溶液中具有较高的稳定性。此外,树脂的磁化过程并不影响其交换容量。     

活性Whipple结构超高速撞击防护性能实验研究

以二级轻气炮作为加载手段,针对以PTFE/Al活性材料为防护屏的Whipple防护结构,开展不同弹丸尺寸、不同碰撞速度的超高速撞击实验。利用激光阴影照相设备,获得并分析了碎片云特性;通过回收的防护结构靶板,研究了活性材料防护结构超高速撞击条件下的后板损伤特性;通过与经典Christiansen撞击极限方程对比,获得活性材料Whipple结构防护性能,并拟合得到新型防护结构的撞击极限曲线。结果表明,相较于同面密度铝合金材料,活性材料超高速撞击条件下的冲击起爆反应使得碎片云中具有侵彻能力的碎片大幅减少,从而显著提升航天器的防护能力,撞击速度为2.31 km/s时最大可提升45%。     

匀质半旋转面绕旋转轴转动的面积矩的数值计算

讨论了鼓形面和花瓶形面特殊形状匀质半旋转面对旋转轴的面积矩.用Mathematica编程对这两类刚体的面积矩进行了数值计算,并拟合出了其多项式表达式,从而可快速计算出这一类旋转刚体的面积矩.     

Analysis of capacity and outage probability for intersatellite optical communications in the presence of random pointing jitter

This work is motivated by the need to achieve the Shannon channel capacity for intersatellite optical communication with intensity modulation and direct detection. In this paper, we investigate the tradeoff between the channel capacity and the outage probability in the presence of random pointing jitter for intersatellite optical links. First, we derive an analytical expression of the outage probability in the absence of bias error, and then the bias error is taken into account. By minimizing the outage probability, we obtain analytically the optimum design of the beam half-width divergence angle $ w_0^{\text{opt}} $ for a given channel code rate. Furthermore, we discuss the tradeoff between the outage probability and the channel capacity and illustrate the results by adopting $ w_0^{\text{opt}} $ in the presence of random pointing jitter. The results obtained are useful for the parametric-estimation optimization of intersatellite optical communication systems.