基于脉冲石英增强光声光谱的中红外超高灵敏CO探测

发展了一种超高灵敏的CO痕量气体测量装置,该装置采用4.65μm脉冲式中红外外腔量子级联激光器作为激发光源,结合石英增强光声光谱技术,对2135~2225cm-1之间的CO基频振动光谱带R支进行连续光谱扫描。水被加入到被测气体中,以加快较慢的CO分子振动-平动弛豫率。在锁相放大器时间常数为3ms,激光器占空比和扫描速率为50%和18cm-1/s时,获得的最小探测极限为4.6×10-8(体积分数),与之对应的归一化噪声等效吸收系数为1.07×10-8 cm-1 W/Hz。     

Uncertainty and Certainty Relations for Pauli Observables in Terms of Renyi Entropies of Order α∈ （0; 1]

We obtain uncertainty and certainty relations of state-independent form for the three Paufi observables with use of the Renyi entropies of order α∈ （0; 1]. It is shown that these entropic bounds are tight in the sense that they are always reached with certain pure states. A new result is the condition for equality in Renyi-entropy uncertainty relations for the Pauli observables. Upper entropic bounds in the pure-state case are also novel. Combining the presented bounds leads to a band, in which the rescaled average Renyi a-entropy ranges for a pure measured state. A width of this band is compared with the Tsallis formulation derived previously.     

教科书的内容应当重视科学发生的过程--漫谈课程标准《高中物理必修1》的编写思想

在《普通高中物理课程标准(实验)》(以下简称《课标》)中，关于教科书的编写建议部分，在内容选择上提出了6条意见，其中有一条是“教科书的内容应当重视科学发生的过程”．如何来理解这条意见?在教科书的编写中又如何实现?下面谈一谈我们的认识与做法．     

New terahertz dispersive device for single-shot spectral measurements of terahertz pulse

A new terahertz dispersive device designed for single-shot spectral measurements of broadband terahertz pulses is proposed. With two-dimensional quasi-randomly distributed element design, the device exhibits approximately the dispersive property of single-order diffraction in far field. Its far-field diffraction pattern is experimentally verified employing a continuous terahertz source centered at 2.52 THz and a pyroelectric focal-plane-array camera, which is in good agreement with the numerical result. The device provides a new approach for direct single-shot spectral measurements of broadband terahertz waves.     

离线测量钍快中子裂变反应率方法

钍快中子裂变反应率是钍铀燃料循环中的重要数据.为了测量基于聚变-裂变混合能源堆包层概念设计的钍样品在宏观中子学装置中的钍快中子裂变数据,发展了钍快中子裂变率的离线活化γ测量方法.通过测量232Th裂变碎片85mKr的β衰变产物85Rb发射的151.16 keV特征γ射线,并结合钍裂变产额数据,获得了钍样品装置中232Th裂变反应率的分布.详细介绍了此方法的原理和影响因素,并利用14 MeV的D-T中子源在贫铀球壳中开展了校验实验,实验不确定度为5.3%—5.5%.采用MCNP5程序和ENDF/B-VI及ENDF/B-VII数据库模拟计算的结果与实验结果在实验不确定度内基本符合,这证明该方法能够有效地模拟装置中232Th裂变反应率.     

Probing Majorana Bound States in T-Shaped Junctions

We investigate the transport properties of a pair of Majorana bound states in a T-shaped junction, where two normal leads are coupled with an identical Majorana bound state. Both the scattering matrix and the recursive Green function method show that the peak value of the differential conductance （Gpeak） in units of e2/h and the shot noise Fano factor in the zero bias limit （F0）, which are measured at the same lead and zero temperature, satisfy a linear relation as F0=1＋Gpeak/2, independent of the magnitude or symmetry of the coupling strengths to the leads. Therefore, combined measurements of the differential conductance and shot noise in the T-shaped geometry can serve as a characteristic signature in probing Majorana bound states.     

"神舟"号飞船的微重力测量

航天器在太空自由漂移时出现失重状态．当存在各种干扰力时，呈现微重力状态．失重状态使得物体各部分之间不产生压力作用或者形变作用，对此开展的研究称之为微重力科学．微重力用微重力加速度的值度量．准稳态加速度来自大气阻力、潮汐力、太阳辐射压等，分析得到“神舟”号飞船的准稳态加速度在10^-7g0以下．瞬变加速度和振动加速度可用石英挠性加速度计检测．“神舟”号飞船的微重力测量仪器具有三轴检测、守时、统计分析、依照预先注入的指令准实时传送微重力统计数据或原始数据的能力．该仪器带宽为(0．06—100)Hz，分辨率5μg0，量程(-10— 10)mg0，沿飞行轴线还有一个放大为(-150— 150)mg0的量程．该仪器对“神舟一号”到“神舟五号”各艘飞船轨道运行段实施全过程连续监测，准实时提供了飞船各种动作发生的时刻及引起的加速度量值，为飞船飞行控制、有效载荷动作监测和空间微重力科学实验分析提供了有效服务。     

干涉光杠杆测量原理及应用

本文分析了用激光干涉法,使用光杠杆的测微原理,这种测微原理具有精度高、测量快、实时显示的特点,对检测高乎整度器件有广泛的应用。     

几个(n,d),(n,t)和(n,n'α)反应截面的测量

本文报告了En～14MeV中子以²⁷Al(n,α)²⁴Na或⁹³Nb(n,2n)^92mNb反应截面为中子注量标准测得的⁹²Mo(n,d*)^91mNb,¹⁰⁶Cd(n,d*)¹⁰⁵Ag;⁵⁴Fe(n,t)^52m+gMn,⁵⁸Ni(n,t)⁵⁶Co;⁵¹V(n,n'α)⁴⁷Sc和⁹²Mo(n,n'α)⁸⁸Zr的反应截面.文中还列举了能收集到的数据以作比较,中子能量是用铌锆截面比法测定的.     

彩色显示器上大色差的研究

在彩色显示器上新的主观色差评价实验表明:CIELUV颜色空间色差公式中彩度差的权重相对于明度差的权重而言显著偏高了.