位相物体激光全息二次曝光法无损检测

为借助激光全息进行无损检测，获得位相物体的信息，对位相物体激光全息二次曝光法无损检测进行了研究，指出一般的二次曝光法测位相物体典型光路的缺点，提出了物光波2次通过样品的改进方案。利用此方案对一些位相物体(如普通玻璃和有机玻璃)作了无损检测实验，得到了较满意的实验结果。与普通检测方法相比，该方法具有精度高、结果直接可靠、不损伤物体等诸多优点。对改进方案稍作改动，即可用于塑料制品和玻璃制品生产线对加工产品进行在线产品质量监控。     

40Ar+238U 实验介绍

主要介绍了利用兰州重离子加速器提供的270 MeV的40Ar离子束轰击238U靶，通过熔合蒸发反应进行试合成Z=110附近的新同位素的实验情况。分析了目前关于超重核研究的现状并描述了这次实验的目的、 可行性分析、 实验装置以及实验过程等。本次实验仍然用氦喷嘴技术对产物进行传输， 并用一套具有数对探测器组的转轮收集探测系统对产物进行收集和测量。 The state of the experiment to produce the new isotopes around Z=110 are presented in this paper. The emphasis is laid upon introducing the experiment purpose, the set up and the feasibility for producing this objective nuclide. In the experiment the new isotopes were produced by the complete fusion evaporation reaction of 238U with 270 MeV 40Ar at the Sector Focus Cyclotron (SFC) of Heavy Ion Research Facility in Lanzhou(HIRFL). The reaction products were also transported and collected by using the helium jet technique and rotating wheel apparatus.     

Application of Electron-Shelving Detection via 423 nm Transition in Calcium-Beam Optical Frequency Standard

A new scheme of small compact optical frequency standard based on thermal calcium beam with application of 423 nm shelving detection and sharp-angle velocity selection detection is proposed. Combining these presented techniques, we conclude that a small compact optical frequency standard based on thermal calcium beam will outperform the commercial caesium-beam microwave dock, like the 5071 Cs clock （from Hp to Agilent, now Symmetricom company）, both in accuracy and stability.     

基于电磁拓扑的多腔体屏蔽效能快速算法

提出基于电磁拓扑理论计算开孔多腔体屏蔽效能的快速方法.首先给出双腔体等效电路和电磁拓扑信号流图,并推导孔缝节点处的散射矩阵,给出拓扑网络的散射矩阵方程和传输矩阵方程,获得双腔体的广义Baum-Liu-Tesche(BLT)方程.在此基础上研究了开孔三腔体,包括串型级联三腔体和串并型混合级联三腔体的广义BLT方程.对于串型级联三腔体,其电磁拓扑网络和广义BLT方程在双腔体基础上直接扩展即可获得.而对于串并型混合级联三腔体,通过将位于三腔体公共面上的孔缝等效为三端口网络节点,并根据三端口网络散射参数定义推导获得该节点的散射矩阵,最终得到串并型混合级联三腔体的广义BLT方程.本文方法对双腔体的计算结果与文献结果和实验结果相符合,对3组不同类型和尺寸开孔腔的屏蔽效能的计算结果与时域有限差分法计算结果符合较好.该算法不仅效率高,通过对所有计算结果和实验结果的误差统计分析,表明该算法具有较高的计算准确度.     

Single-Photon Emission from a Single InAs Quantum Dot

Excitation power-dependent micro-photoluminescence spectra and photon-correlation measurement are used to study the optical properties and photon statistics of single InAs quantum dots. Exciton and biexciton emissions, whose photoluminescence intensities have linear and quadratic excitation power dependences, respectively, are identified. Under pulsed laser excitation, the zero time delay peak of second order correlation function corresponding to exciton emission is well suppressed, which is a clear evidence of single photon emission.     

酯基取代的吲哚衍生物的红外和荧光光谱研究

Tryptophan derivatives have long been used as site-specific biological probes. 4-Cyanotryptophan emits in the visible region and is the smallest blue fluorescent amino acid probe for biological applications. Other indole or tryptophan analogs may emit at even longer wavelengths than 4-cyanotryptophan. We performed FTIR, UV-Vis, and steady-state and time-resolved fluorescence spectroscopy on six ester-derivatized indoles in different solvents. Methyl indole-4-carboxylate emits at 450 nm with a long fluorescence lifetime, and is a promising candidate for a fluorescent probe. The ester-derivatized indoles could be used as spectroscopic probes to study local protein environments. Our measurements provide a guide for choosing esterderivatized indoles to use in practice and data for computational modeling of the effect of substitution on the electronic transitions of indole.     

温度对PIN二极管限幅器功率响应特性的影响

 通过求解PIN二极管基区双极载流子扩散方程得到了限幅器Pspice等效电路模型, 根据PIN二极管物理参数与温度的关系, 数值计算得到了PIN二极管限幅器在多个温度点的功率响应特性, 发现温度的升高会使限幅器内部损耗增加, 加剧限幅器内部热损伤。并利用恒温控制系统进行了实验验证, 实验结果与数值计算结果相符合。实验还发现高温热冲击可能使限幅器限幅能力大幅下降, 可能成为通信系统的重大安全隐患。     

ICP-MS测定食管鳞癌患者各组织中微量元素的含量差异

建立了冷冻干燥微波消解-ICP-MS测定25例食管鳞癌患者手术的癌组织与正常组织中22种元素的方法。样品经真空冷冻干燥后研磨成粉,采用纯硝酸体系微波消解,优化仪器工作各项参数后,以Sc,Ge,Y,In等混合内标进行校正。采用化学计量学方法分析癌组织和正常组织中元素的差异性,实验结果表明,食管鳞癌组织与正常组织有明显的分离趋势,所建立的PLS-DA模型能较好地解释所有的样品信息并能准确地预测未知样品的分类。癌组织的元素代谢情况与正常组织相比具有显著差异,从而揭示了食管鳞癌与元素之间存在着内在联系。     

利用高压热处理技术提高Bi-2223/Ag高温超导带材临界电流

提高临界电流密度(Jc)对促进Bi-2223/Ag高温超导带材的应用有着重要意义.在常压热处理条件下所制备的带材中存在大量的裂纹、孔洞和第二相颗粒等,这些因素都会对带材的超导连接性能产生破坏作用.我们成功建立了一套可用氧气氛的热等静压设备,工作气压和温度可同时达到15MPa和850°C.通过引入裂纹愈合热处理过程,我们成功对带材进行了高压热处理,所得样品中第二相颗粒和裂纹数量大幅度降低,77K、自场下的临界电流相比常压热处理样品提高了20%左右.     

新型Eu~(3+)、Tb~(3+)掺杂配合物的合成与荧光性能研究

合成了稀土(Eu3+和Tb3+)与二苯甲酰甲烷(DBM)、2,2′-联吡啶(Dipy)的一系列稀土配合物EuxTb1-x(DBM)3Dipy。元素分析和红外分析确定了配合物的组成,荧光光谱研究了荧光性质。铽掺入配合物后,铽能极大地增强铕的特征荧光,铽对铕配合物的发光有协同作用。在该系列配合物中,不仅有机配体可以将吸收的能量传递给发光的铕离子使其发光,而且铽离子也可将其吸收的能量通过分子内能量传递给铕离子。