液体表面波及其谐波的光衍射效应

为了探究液体表面波的波动规律,提出了一种基于激光衍射的探测方法.未扩束的激光束直接斜入射到波动液面,液面波动的强度由电磁式激发器控制、频率由信号发生器控制,用CCD采集光衍射图样并传送到计算机中实时处理.根据波动光学理论,给出了衍射光场和液体表面波之间的解析关系,发现实验现象和理论分析吻合.实验结果表明:该方法具有实时、准确、无损的特点.     

脱氧雪腐镰刀菌烯醇与溶菌酶相互作用的研究

利用荧光猝灭、紫外光谱(UV)、傅里叶变换红外光谱(FTIR)和圆二色性光谱(CD)法测定反应的结合常数、主要作用力以及脱氧雪腐镰刀菌烯醇对溶菌酶二级结构的影响;并综合实验所得的热力学参数结果,确定二者间的作用力。脱氧雪腐镰刀菌烯醇与溶菌酶有较强的结合,脱氧雪腐镰刀菌烯醇对溶菌酶的荧光猝灭以氢键和范德华力为主,结合位置与色氨酸残基间的距离r为4.62nm。通过光谱法研究模拟生理条件下真菌毒素脱氧雪腐镰刀菌烯醇与溶菌酶的相互作用,为脱氧雪腐镰刀菌烯醇在体内的储存、运输及毒性机制提供一些具有指导作用的信息。     

Dressed Four-Wave Mixing Spectroscopy Modified by Polarization Interference and Atom-Wall Collision in Micrometric Thin Cells

Dressed four-wave mixing （DFWM） spectroscopy is investigated theoretically in some micrometric thin cells. It is found that DFWM spectra can be modified by polarization interference of atoms and transient effects induced by atom-wall collision. This modification can lead to width-narrowing of DFWM lines and facilitates to implement experiment of high resolution DFWM spectroscopy in a confined atomic system.     

Investigation on Guided-Mode Characteristics of Hollow-Core Photonic Crystal Fibre at Near-Infrared Wavelengths

Guided-mode characteristics of hollow-core photonic crystal fibre （HC-PCF） are experimentally and theoretically investigated. The transmission spectrum in the range from 755 to 845nm is observed and the loss is measured to be 0.12dB/m at 800nm by cut-back method. Based on the full-vector beam propagation method and the full-vector plane-wave method, the characteristics of mode field over propagation distance 1 m are simulated, and the results show that the propagation efficiency can be above 80%. Compared with the fundamental guided mode well confined in air core within shorter propagation distance, the second-order guided mode leaks into the cladding region and gradually attenuates due to larger refractive index difference. The primary loss factors in HC-PCF and the corresponding solutions are elementarily discussed.     

碳纳米管热导率的分子动力学研究

采用非平衡分子动力学方法研究了室温下(5,5)碳纳米管的热导率.当管长从6 nm增加到4 μm时,其热导率从30 W/(m.K)增加为1000 W/(m.K).当碳纳米管长度小于40 nm时,热导率与长度呈线性关系,此时导热处于弹道输运阶段.随着管长的增加,热导率和长度成幂指数关系,但幂指数逐渐减小并趋向于O,表明声子从以弹道输运为主向以扩散输运为主的机制转变.     

Studies of closed orbit correction and slow orbit feedback for the SSRF storage ring

Details of the active ways to suppress Closed Orbit Distortion (COD), including bending magnet sorting and survey and alignment of the magnets, are discussed based on the studies of affections to the COD by the bending magnet field error and the misalignment of quadrupoles. The closed orbit correction and the Slow Orbit Feed Back (SOFB) system for the SSRF storage ring are presented in this paper. With these available methods, better results were obtained during the commissioning period with 3 GeV beam energy.     

一维光子晶体中亚波长缺陷膜对Goos-Hnchen位移的调制特性

利用传输矩阵法分析一维光子晶体中亚波长缺陷膜对缺陷模频率处Goos-Hnchen位移的调制特性,讨论了亚波长缺陷膜的厚度、磁导率及介电常量对一维光子晶体缺陷模频率处的Goos-Hnchen位移的影响.研究发现:一层几何厚度极小的亚波长薄膜即可非常灵敏地调制一维光子晶体缺陷模频率处Goos-Hnchen位移的位置及其大小;并且当亚波长缺陷膜为左手材料时,Goos-Hnchen位移随亚波长缺陷膜物理参量的变化趋势与普通右手材料时的情形完全相反.     

Development of a China test cryomodule for ILC

Research and development of a 1.3 GHz 9-cell cavity test cryomodule were carried out by a collaboration group between IHEP (Institute of High Energy Physics) and TIPC (Technical Institute of Physics and Chemistry) in China. The cryomodule is a "test model" for the ILC cryomodule, and a key component of a superconducting accelerator test unit which will be built in the near future, also can be used as a horizontal test facility for 1.3~GHz 9-cell cavities. This paper presents the development status of the cryomodule, including structure design, cryogenic flow diagram, thermal and mechanical simulations, heat load estimation and etc.     

新型混合工质共沸点的判定与预测

随着新型混合工质的不断提出,建立准确判定和预测混合工质共沸点的方法具有重要价值.本文在分析共沸点形成条件的基础上,针对多种含氢氟烃混合体系,使用气液相平衡预测模型建立了共沸点计算方法,判断了多种混合体系是否共沸,对于共沸体系预测了其共沸点,并与相关文献值进行了比较,结果表明本文方法具有广泛的适用性和良好的预测精度.     

ARL 9800XP型X射线荧光光谱仪的故障及维修

介绍了一例ARL-9800X射线荧光光谱仪的故障及故障排除的措施。