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991.
Dr. Kuirun Zhang Dr. Soonchul Kang Dr. Zi‐shuo Yao Kazusa Nakamura Dr. Takashi Yamamoto Prof. Dr. Yasuaki Einaga Nobuaki Azuma Dr. Yuji Miyazaki Prof. Dr. Motohiro Nakano Dr. Shinji Kanegawa Prof. Dr. Osamu Sato 《Angewandte Chemie (International ed. in English)》2016,55(20):6047-6050
Heterometallic Prussian blue analogues are known to exhibit thermally induced charge transfer, resulting in switching of optical and magnetic properties. However, charge‐transfer phase transitions have not been reported for the simplest FeFe cyanide‐bridged systems. A mixed‐valence FeII/FeIII cyanide‐bridged coordination polymer, {[Fe(Tp)(CN)3]2Fe(bpe)?5 H2O}n, which demonstrates a thermally induced charge‐transfer phase transition, is described. As a result of the charge transfer during this phase transition, the high‐spin state of the whole system does not change to a low‐spin state. This result is in contrast to FeCo cyanide‐bridged systems that exhibit charge‐transfer‐induced spin transitions. 相似文献
992.
通道调制型偏振成像系统中,焦平面上获取的信息需要通过目标偏振参量的重建才能有效提取,因而重建是目标识别、材料分析、生物医疗等技术进一步应用的前提.为了实现在非理想情况下通道调制型偏振成像系统的偏振参量精确重建,需要解决成像系统中电荷耦合器件(CCD)采样频率与频谱位置偏移对重建的影响.本文首先详细分析了频谱不发生混叠的条件:CCD采样频率应至少为4倍基频;在偏振干涉频谱位置偏移时,使用最大频谱法确定各个偏振态的载波频率,通过频移、滤波和傅里叶变换获得目标的偏振重建二维图像;最后通过计算机模拟仿真与实验分析结合的方法验证该重建方案的可行性与有效性.模拟与实验结果表明:改进后的偏振重建法得到的偏振图像与原始输入图像的均方差在0.001以下,峰值信噪比有明显的提高,且结构相似度可达到0.9以上,表明该方法获得的二维偏振态重建图像精度高,与理论偏振解调法相比具有很大的优越性.该工作希望为后续偏振探测与分析进一步的研究提供参考. 相似文献
993.
有机聚集体中分子间相互作用决定了聚集体的光物理性质,从而显著影响基于此类材料的光伏器件性能. 分子间激子耦合(或电偶极耦合)是一种常见且重要的分子间相互作用. 本文利用瞬态吸收光谱研究了石墨烯量子点二聚体(一种大稠环芳烃的π-π堆叠二聚体)中的激子耦合作用. 发现了瞬态吸收谱随泵浦-探测延时的演化起源于二聚体激发态中激子耦合强弱的动态变化. 通过拟合瞬态光谱,进一步证实了可利用最低能量的两个振动吸收峰的瞬态吸收动力学直接表征二聚体中激子耦合强度的动态变化. 相似文献
994.
995.
Jiliang Zhang Yong-Mook Kang Guangcun Shan Svilen Bobev 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(5):562-567
The crystal structure of the gadolinium iron bismuthide Gd6FeBi2 has been characterized by single‐crystal X‐ray diffraction data and analyzed in detail using first‐principles calculations. The structure is isotypic with the Zr6CoAl2 structure, which is a variant of the ZrNiAl structure and its binary prototype Fe2P (Pearson code hP9, Wyckoff sequence g f d a). As such, the structure is best viewed as an array of tricapped trigonal prisms of Gd atoms centered alternately by Fe and Bi. The magnetic‐ordering temperature of this compound (ca 350 K) is much higher than that of other rare‐earth metal‐rich phases with the same or related structures. It is also higher than the ordering temperature of many other Gd‐rich ternary phases, where the magnetic exchange is typically governed by Ruderman–Kittel–Kasuya–Yosida (RKKY) interactions. First‐principles calculations reveal a larger than expected Gd magnetic moment, with the additional contribution arising from the Gd 5d electrons. The electronic structure analysis suggests strong Gd 5d–Fe 3d hybridization to be the cause of this effect, rather than weak interactions between Gd and Bi. These details are of importance for understanding the magnetic response and explaining the high ordering temperature in this material. 相似文献
996.
Ling-Bin Kong Mao-Cheng Liu Jun-Wei Lang Min Liu Yong-Chun Luo Long Kang 《Journal of Solid State Electrochemistry》2011,15(3):571-577
A new porous cobalt hydroxide film has been successfully electrodeposited on nickel foam from 0.1?M cobalt nitrate electrolyte at ?1.0?V vs. SCE without adding any surfactant. The microstructure and surface morphology of prepared cobalt hydroxide films were physically characterized by X-ray diffraction analysis and scanning electron microscopy. The results indicate that an interlaced network structure was obtained. The effects of electrodeposition time, deposition potential, and different substrates on the specific capacitance and microstructure of prepared porous ??-Co(OH)2 thin film were systematically studied. The results indicate that the film deposited on nickel foam at ?1.0?V has excellent electrochemical properties. A maximum specific capacitance of 1473?F?g?1 could be achieved at a current density of 2?A?g?1. 相似文献
997.
Ai‐Zheng Chen Xi‐Ming Pu Yun‐Qing Kang Li Liao Ya‐Dong Yao Guang‐Fu Yin 《Macromolecular rapid communications》2006,27(15):1254-1259
Summary: 5‐Fluorouracil‐poly(L ‐lactide) (5‐Fu‐PLLA) microparticles have been prepared by an SEDS process. First, the 5‐Fu is successfully micronized and is then used to produce the 5‐Fu‐PLLA microparticles. The 5‐Fu‐PLLA microparticles synthesized by the SEDS process exhibit a rather spherical shape and a narrow particle size distribution, where it ranges from 615 to 1 990 nm, with a mean particle size of 980 nm. The dichloromethane residue in the 5‐Fu‐PLLA microparticles without any further treatment is 46 ppm. The average drug load and encapsulation efficiency of the 5‐Fu‐PLLA microparticles are 3.05 and 17.8%, respectively. The rate of drug release from the 5‐Fu‐PLLA microparticles shows mainly first‐order kinetics.
998.
Xia Xiao Hai-Peng Song Yi-Lan Kang Xiao-Lei Li Xiao-Hua Tan Hao-Yun Tan 《Acta Mechanica Sinica》2012,28(2):432-437
A three-nested-deformation model is proposed to describe crack-tip fields in rubber-like materials with large deformation.The model is inspired by the distribution of the measured in-plane and out-of-plane deformation.The inplane displacement of crack-tip fields under both Mode I and mixed-mode(Mode I-II) fracture conditions is measured by using the digital Moire’ method.The deformation characteristics and experimental sector division mode are investigated by comparing the measured displacement fields under different fracture modes.The out-of-plane displacement field near the crack tip is measured using the three-dimensional digital speckle correlation method. 相似文献
999.
In this paper, we consider the existence of at least three positive solutions of singular nonlocal boundary value problems for systems of nonlinear second-order ordinary differential equations. The associated Green’s function for the boundary value problems is first given. The proofs of our main results are based upon the Leggett–Williams fixed point theorem. Finally, we give an example to demonstrate our result. 相似文献
1000.