磁场作用下的有机电致发光

分别制备了荧光器件ITO/NPB/Alq₃/LiF/Al和磷光器件ITO/NPB /CBP: Ir（ppy）₃/BCP/Alq₃/LiF/Al, 测试了50 mT磁场作用下器件的I-V和L-V特性. 与零磁场相比荧光器件和磷光器件的效率分别增加了44%和7%. 从有机电致发光的机制出发对该现象进行了解释, 认为外加磁场可以使三重态激子发生塞曼分裂, 进而在荧光器件中引起了三重态激子T     

截断误差导致的非双曲不动点邻域拓扑变异

提供一个关于截断误差使简单系统复杂化的直接实验证据,以此证明存在混沌抗退化机理.分别构造了一个一维圆弧迭代系统和一个一维抛物线迭代系统,两者均有一个非双曲不动点,其迭代序列被证明是简单极限序列,数字计算实验显示这两个迭代系统都存在可以越过不动点的序列.采用计算"元胞"分析方法清晰地展示了截断误差导致非双曲不动点邻域拓扑变异:形成第I类阵发混沌通道,或产生纹波分岔.     

二维材料“遇见”生物大分子:机遇与挑战

二维材料的超薄原子层结构使其具有独特的力学性能、导热导电性以及巨大的比表面积,在能源存储、催化、传感和生物医学等领域引起了国内外学者的广泛关注。将二维材料与具有生物活性的生物大分子相结合可以为开发具有优异电学、力学和生物学功能的特种功能材料提供新的方法和途径。近年来,科研工作者针对这一方向展开了广泛的研究,取得了一系列重要的成果,使二维材料与生物大分子的结合与应用成为了新的研究热点。本文综述了近年来二维材料和生物大分子之间的相互作用及应用的研究进展,重点介绍了二维材料与生物大分子在分子水平上的相互作用机理,还总结了基于二维材料与生物大分子之间的相互作用在工程、疾病治疗和抗菌中的应用,并对其未来的研究趋势提出了展望。     

Implementation Scheme of Two-Photon Post-Quantum Correlations

The pre-and post-selection processes of the "two-state vector formalism" lead to a fair sampling loophole in Bell test, so it can be used to simulate post-quantum correlations. In this paper, we propose a physical implementation of such a correlation with the help of quantum non-demolition measurement, which is realized via the cross-Kerr nonlinear interaction between the signal photon and a probe coherent beam. The indirect measurement on the polarization state of photon is realized by the direct measurement on the phase shift of the probe coherent beam, which enhances the detection efficiency greatly and leaves the signal photon unabsorbed. The maximal violation of the CHSH inequality 4 can be achieved by pre-and post-selecting maximally entangled states. The reason why we can get the post-quantum correlation is that the selection of the results after measurement opens fair-sampling loophole. The fair-sampling loophole opened here is different from the one usually used in the currently existing simulation schemes for post-quantum correlations,which are simulated by selecting the states to be measured or enlarging the Hilbert space. So, our results present an alternative way to mimic post-quantum correlations.     

薄壁快脉冲252Cf裂变电离室的研制及性能测试

介绍了用于中子探测器效率刻度的薄壁快脉冲252Cf裂变电离室。 在用飞行时间法测量中子能谱时, 该裂变电离室能够给出252Cf裂变中子发射时刻信号, 输出脉冲上升时间约为5.5 ns, 电离室由厚度为0.15 mm的不锈钢构成。 测试结果表明, 对裂变碎片的探测效率为99.2%, α粒子脉冲幅度和碎片脉冲幅度可清晰分开。A thin wall, fast pulse 252Cf ionization chamber, which was designed for calibrating efficiency of neutron detectors, was described. The ionization chamber can be used as the start detector in time of flight measurements of the 252Cf fission neutron spectrum. The chamber is composed of 0.15 mm thick stainless steel, the rise time of pulse signals is about 5.5 ns. As the test result shows, the detection efficiency of fission fragments is 99.2%, and pulse signals caused by fissions are distinguished clearly from those caused by α decays.     

Structure and bonding properties of Y doped ∑37 grain boundary in alumina

The microscopic structures and the bonding properties of Y-doped and undoped(0118)/[0441]/180?(Σ37) grain boundaries in alumina are investigated by using ab initio method.The formation energy of grain boundary and the segregation energy of Y to grain boundary are acquired.Electronic structures,potential distributions,bond orders and effective charges of Y-doped and undoped Σ37 GB systems are calculated.Our results reveal that the higher strength Y-O bond than Al-O bond is ascribed to the hybridization of Y(4p,3d) with O(2s).Meanwhile,dopant Y also causes a change in potential distribution in the grain boundary region,thereby further aflecting the transport property of ceramic alumina.     

“双碳”理念下《功能高分子材料》的实验教学初探——以“双重温度响应水凝胶的制备及智能窗光热调控应用”为例

加强“双碳”高等教育,助力实现碳达峰碳中和,对新时代人才培养提出了挑战。本文分析了《功能高分子材料》的课程现状,积极思考“双碳”背景下课程内容和教学模式的改革举措,将温敏水凝胶材料的设计合成与智能窗光热调控应用科研成果纳入到教学体系中,在实验原理、实验目的、应用研究中贯彻“双碳”理念,把学科前沿研究转化为本科教学的实验改革,全面提升学生的科学素养、团队合作能力以及创新实践能力,为实现“双碳”目标提供可持续的人才保障和支撑。     

室温下磁场对基于Alq3的有机电致发光器件的影响

制备了ITO/NPB/LiF/Alq₃/LiF/Al的器件,测量了该组器件效率和亮度的磁效应.结果表明,在50 mT磁场中,当LiF缓冲层厚度为0.8 nm时,器件的效率最大增加了12.4%,磁致亮度最大变化率17%.同时,制备的磷光器件ITO/NPB/LiF/CBP:6 wt% Ir(ppy)₃/BCP/Alq₃/ LiF/Al,在50mT磁场作用下,当LiF缓冲层的厚度为0.8 nm时,器件的效率最大增加12.1%.在Alq_{3 关键词： 有机发光 磁场 效率 磁致亮度}     

迈克尔逊干涉仪气体泄漏监测装置的研制

分析用于气体泄漏监测的迈克尔逊干涉的工作原理,介绍装置的软件、硬件设计,并对设计进行仿真,做出实物并证明此装置能够实现气体泄漏实时监测报警功能。     

Scheme for concentration of the unknown GHZ entangled states

We propose two schemes for concentrating unknown nonmaximally tripartite GHZ entangled states via cavity quantum electrodynamics (QED) techniques. The finial pure states obtained from the two schemes are shared by two or three parties. Our schemes only require large-detuned interaction between two driven atoms and the quantized cavity mode, which is insensitive to both the cavity decay and thermal field, thus the schemes are well within current experimental technology.