Strong Correlation of Fluorescence Photons without Quantum Interference

It has been predicted that a driven three-level V atom can emit strongly correlated fluorescence photons in the presence of quantum interference. Here we examine the effects of quantum interference on the intensity correlation of fluorescence photons emitted from a driven three-level A atom. Unexpectedly, strong correlation occurs without quantum interference. The quantum interference tends to reduce the correlation function to a normal level. The essential difference between these two cases is traced to the different effects of quantum interference on coherent population trapping （OPT）. For the V atom, quantum interference and coherent excitation combine to lead to OPT. For the A atom, however, the quantum interference tends to spoil OPT while the coherent excitation induces the effect.     

Effects of E2 and El-E2 Interference on Coulomb Dissociation of 19C

We investigate the effects of higher order multipole transitions, in particular electric quadrupole （E2） and El-E2 interference, on the Coulomb dissociation of 19 C within the framework of the first order eikonal approximation. The sensitivity of the total Coulomb breakup cross section and the longitudinal momentum distribution of the core fragment to these effects are checked. The breakup occurs predominately through the dipole transition and the contribution of E2 transition to the total cross section is found to be within the range from 1 to 3% of that of El. It is further observed that the El-E2 interference term contributes nothing to the integrated cross section. On the other hand, the longitudinal momentum distribution is observed to be insensitive to the E2 transition while the El-E2 interference introduces a small asymmetry in its shape.     

Information-Disturbance Tradeoff in Estimating the Unknown Three-Qubit GHZ State

In a recent paper, Sacchi （Phys. Rev. Lett. 96 （2006） 220502） studied the information-disturbance tradeoff in estimating an unknown two-qubit maximally entangled state. In this study, we explore the tradeoff in estimating 13 an unknown three-qubit GHZ state. The optimal estimation process supplies a fidelity of 13/54 and the tradeoff interpolates smoothly between non-informative measurement and optimal estimation process.     

光电信息技术与信息化战争第九讲信息战的局限性(续)

信息时代的战争是信息化的战争，使用现代信息技术和装备进行的旨在夺取制信息权的信息战已成为信息化战争的一个重要作战样式。现在，任何战争都离不开信息战的加盟。按动侦察与干扰装置的开关就如同以往传统战争中抠动步枪和火炮的扳机一样那么自然和平常。     

数学选择题求解中的功亏一篑

虽然高考的改革在深入地进行,各科试卷的题型也在变化,但数学选择题以其"短、快、灵"的特点,仍然占据重要的一席之地.具有举足轻重的作用,尤其是命题者为了提高试题的区分度,常会在选择题上下功夫,这是因为数学选择题的选择支可以说是一把"双刃剑",一方面它具有一定的提示作用,另一方面它也具有干扰作用,它能导致数学素养低的学生解题中发生"为山九仞,功亏一篑"的现象,这也常令考生扼腕叹息,懊恼不己,这是怎么回事呢?本文试举例说明.……     

THE GENERALIZED RIEMANN PROBLEM FOR A SCALAR COMBUSTION MODEL --THE PERTURBATION ON INITIAL BINDING ENERGY

In this paper, we study the generalized Riemann problem for a scalar Chapman-Jouguet combustion model in a neighborhood of the origin on upper half of the （x, t）plane. We focus our attention on the perturbation on initial binding energy. Under the entropy conditions, the solutions are obtained constructively. It shows that the perturbed Riemann solutions possess the structural stability except the case that the corresponding Riemann solutions contain CJDT, for which CJDT may transform into SDT after perturbation on initial binding energy in the neighborhood of the origin.     

一类带有Holling Ⅱ类功能性反应和相互干扰及脉冲效应的捕食系统

A kind of predator-prey system of Holling typeⅡand interaction perturbation with impulsive effect is presented.By using Floquet theory and small amplitude perturbations skills,the locally asymptotical stability of prey-eradication periodic solution and the permanence of the system are discussed and the corresponding threshold conditions are given respectively.Finally,the existence of positive periodic solution is investigated by the bifurcation theory.     

新体制引信干扰机理分析

为应对新体制无线电引信带来的威胁,从引信对抗角度以超宽带无线电引信为研究对象,研究干扰作用下其失效机理。揭示了超宽带无线电引信敏感干扰波形响应机理,理论推导了周期调制干扰信号作用下引信响应特性,仿真计算了在射频噪声、正弦波调幅、正弦波调频以及扫频正弦波调幅干扰信号作用下超宽带引信接收机相关器输出响应特性。以干信比增益为表征参量,通过理论计算、仿真及试验验证得出结论:周期类调制干扰中调幅类干扰对超宽带引信干扰效果最好。     

超高效液相色谱-串联质谱多目标分析生物样品中的微量内分泌干扰污染物

建立了生物样品中9种微量内分泌干扰物(EDCs)的多目标分析方法.采用旋涡振荡-超声波辅助萃取,结合凝胶渗透色谱(GPC)除去大分子有机物干扰,再经硅胶柱层析进一步净化,最后应用超高效液相色谱-串联质谱(UHPLC-MS/MS)检测.GPC采用乙酸乙酯-环己烷混合溶液(1:1,V/V)为流动相,选择12~28 mL为目标化合物馏分的收集段;质谱采用电喷雾离子源正离子模式和大气压化学电离源负离子模式,数据采集为多重反应监测模式.方法回收率为65.2%~118.0%,定量限为0.1~9.7 ng/g dw(干重).采用本方法初步分析了珠江水系鲤鱼脊肉中的内分泌干扰污染物,结果表明,除均二苯腺和三氯卡班未被检出外,其它内分泌干扰污染物的含量为0.1~22.6 ng/g dw.