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991.
Xing Guo CHEN Chu Luo YANG Jin Gui QIN Kyuya YAKUSHI Yasuhiro NAKAZAWA Kenji ICHIMURA 《中国化学快报》2003,14(11)
A new intercalation compound, Fe0.85PS3(4,4′-bipyH)0.30 (4,4′-bipy = 4,4′-bipyridine), is obtained by the intercalation of 4,4′-bipyridine·2HCl with lamellar FePS3, which is characterized by elemental analysis, powder X-ray diffraction, infrared spectroscopy. By comparison with the pure FePS3, the lattice spacing of Fe0.85PS3(4,4′-bipyH)0.30 is expanded by ~ 5.7(A), indicating that the ring plane of the guest is perpendicular to the layer of the host. The magnetic property of Fe0.85PS3(4,4′-bipyH)0.30 is studied with SQUID. It exhibits an antiferromagnetic phase transition with TN of about 70 K. 相似文献
992.
Xiao‐Hui Liu Gui‐Bao Zhang Xian‐Feng Lu Jing‐Yu Liu Ding Pan Yue‐Sheng Li 《Journal of polymer science. Part A, Polymer chemistry》2006,44(1):490-498
Reversible addition–fragmentation chain transfer polymerization has been successfully applied to polymerize acrylonitrile with dibenzyl trithiocarbonate as the chain‐transfer agent. The key to success is ascribed to the improvement of the interchange frequency between dormant and active species through the reduction of the activation energy for the fragmentation of the intermediate. The influence of several experimental parameters, such as the molar ratio of the chain‐transfer agent to the initiator [azobis(isobutyronitrile)], the molar ratio of the monomer to the chain‐transfer agent, and the monomer concentration, on the polymerization kinetics and the molecular weight as well as the polydispersity has been investigated in detail. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry and 1H NMR analyses have confirmed the chain‐end functionality of the resultant polymer. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 490–498, 2006 相似文献
993.
In this paper, we consider a nonlinear sublinear Schrödinger equation at resonance in . By using bounded domain approximation technique, we prove that the problem has infinitely many solutions. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
994.
A numerical solution of the quadratic matrix equations associated with a nonsingular M-matrix by using the alternately linearized implicit iteration method is considered. An iteration method for computing a nonsingular M-matrix solution of the quadratic matrix equations is developed, and its corresponding theory is given. Some numerical examples are provided to show the efficiency of the new method. 相似文献
995.
The self-mixing vibration signals are observed in the laser diode when the optical beam is back-scattered into the laser cavity which causes laser output power modulated. Based on these properties, a laser diode self-mixing vibrometer with wide dynamic range is proposed. This current investigation further reports new work to improve the accuracy and range of the measured vibration signals. Numerical simulations and experimental results are given and discussed. The experimental results show that the frequency measurement range can be achieved up to 22 kHz with 0.241% maximum relative error while utilizing the reflecting film. For amplitude measurement utilizing the same reflecting film, the error of measurement result is 4.77 nm which has approached nanometer order of magnitude. 相似文献
996.
Bipartite network based recommendations have attracted extensive attentions in recent years. Differing from traditional object-oriented recommendations, the recommendation in a Microblog network has two crucial differences. One is high authority users or one’s special friends usually play a very active role in tweet-oriented recommendation. The other is that the object in a Microblog network corresponds to a set of tweets on same topic instead of an actual and single entity, e.g. goods or movies in traditional networks. Thus repeat recommendations of the tweets in one’s collected topics are indispensable. Therefore, this paper improves network based inference (NBI) algorithm by original link matrix and link weight on resource allocation processes. This paper finally proposes the Microblog recommendation model based on the factors of improved network based inference and user influence model. Adjusting the weights of these two factors could generate the best recommendation results in algorithm accuracy and recommendation personalization. 相似文献
997.
Wenhui Zhang Yanyan Wu Xu Ji Rong Xiang Xuchun Gui Yuan Zhu Zikang Tang 《Crystal Research and Technology》2013,48(9):599-602
BexZn1‐xO nanorod arrays with high crystalline quality were fabricated on Si substrate by a simple, low‐cost hydrothermal method. The effect of Be‐corporation on the structure, morphology and optical property of ZnO nanorod arrays was investigated. The diameter of BexZn1‐xO nanorods gradually decreased and the length of them increased with increasing Be concentration. Edge emissions of the BexZn1‐xO nanorods show a obvious blue shift upon the increase of the Be content. 相似文献
998.
通过低温和强磁场下的磁输运测量研究了Al0.22Ga0.78N/GaN调制掺杂异质结构中2DEG的子带占据性质和子带输运性质.在该异质结构的磁阻振荡中观察到了双子带占据现象,并发现2DEG的总浓度随第二子带浓度的变化呈线性关系.得到了该异质结构中第二子带被2DEG占据的阈值电子浓度为7.3×1012cm-2.采用迁移率谱技术得到了不同样品的分别对应于第一和第二子带的输运迁移率.发现当样品产生应变弛豫时第一子带的电子迁移
关键词:
AlGaN/GaN异质结
二维电子气
子带占据
输运迁移率 相似文献
999.
1000.
Dr. Feng‐Rong Dai Dr. Yung‐Chung Chen Lai‐Fan Lai Dr. Wen‐Jun Wu Chao‐Hua Cui Gui‐Ping Tan Xing‐Zhu Wang Prof. Jiann‐T'suen Lin Prof. He Tian Prof. Wai‐Yeung Wong 《化学:亚洲杂志》2012,7(6):1426-1434
Four new unsymmetric platinum(II) bis(aryleneethynylene) derivatives have been designed and synthesized, which showed good light‐harvesting capabilities for application as photosensitizers in dye‐sensitized solar cells (DSSCs). The absorption, electrochemical, time‐dependent density functional theory (TD‐DFT), impedance spectroscopic, and photovoltaic properties of these platinum(II)‐based sensitizers have been fully characterized. The optical and TD‐DFT studies show that the incorporation of a strongly electron‐donating group significantly enhances the absorption abilities of the complexes. The maximum absorption wavelength of these four organometallic dyes can be tuned by various structural modifications of the triphenylamine and/or thiophene electron donor, improving the light absorption range up to 650 nm. The photovoltaic performance of these dyes as photosensitizers in mesoporous TiO2 solar cells was investigated, and a power conversion efficiency as high as 1.57 % was achieved, with an open‐circuit voltage of 0.59 V, short‐circuit current density of 3.63 mA cm?2, and fill factor of 0.73 under simulated AM 1.5G solar illumination. 相似文献