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121.
Theoretical studies of vibrationally resolved absorption and emission spectra: From a single chromophore to multichromophoric oligomers/aggregates 下载免费PDF全文
GAO Fang LIANG WanZhen & ZHAO Yi Hefei National Laboratory for Physical Sciences at the Microscale 《中国科学:化学》2010,(2)
Absorption and photoluminescence spectroscopies are useful tools to study the photo-physical properties of materials. The theoretical methods for calculation of the spectra of molecules/supermolecules and aggregates, whose structures can differ significantly, are reviewed from the viewpoint of computational efficiency. Several model compounds/multimers are taken as examples for the spectral calculations. The numerical results achieve a satisfactory agreement between the theory and experiment. 相似文献
122.
A sensitive and convenient method for the study of electrochemical fingerprints of Chrysanthemums from different regions is studied by Belousov-Zhabotinskii(B-Z) oscillation system with malonate as a dissipative material.The results indicated that the electrochemical fingerprints of Chrysanthemums from different regions show significantly different characteristics,and can be used to identify the regions of Chrysanthemums. 相似文献
123.
本文采用层层自组装法合成了具有良好水溶性的功能化磁性荧光Fe3O4/Py(芘)/PAM(聚丙烯酰胺)纳米粒子.利用其磁性,能够对该粒子进行简单有效的分离纯化,并可以对待测粒子进行富集以提高其检测灵敏度.利用Cr(VI)对该复合粒子水溶液的荧光猝灭,建立了测定Cr(VI)的荧光分析法,讨论了反应机理.在最佳实验条件下,该方法的线性区间为0.1~14.0μgmL-1,检测限为0.02μgmL-1.常见的共存离子不干扰测定,该方法可用于环境废水中Cr(VI)的测定. 相似文献
124.
采用脉冲激光沉积法在MgO(100)单晶衬底上制备了Ce0.8Gd0.2O2-δ(CGO)系列薄膜,沉积温度与膜厚对CGO/MgO薄膜的微结构及离子电导率的影响分别被研究.X-ray衍射(2θ-ω线扫描,ω-摇摆曲线,(-扫描)测量显示,随着沉积温度的升高,CGO薄膜的微结构由多晶薄膜演变到外延膜.对沉积在730℃的CGO薄膜(510nm)中较大的离子电导归因于薄膜中较小的晶界密度.对高质外延的CGO薄膜(沉积730℃),随着膜厚的减小,其快速减小的激活能及增大的离子电导可解释为CGO/MgO界面平面的应变态和氧空位的无序分布所致.我们的结果表明,为获得高离子电导的CGO薄膜,最佳的沉积温度和膜厚是需要考虑的. 相似文献
125.
EAST装置做为全超导托卡马克装置,其纵场和极向场线圈全部由超导磁体组成,所以进行安全,准确,有效的超导线圈的失超保护是装置安全运行的首要环节.由于等离子体电流的建立必须由极向场线圈系统提供极快速的磁通变化,随之产生较高的交流损耗使得极向场线圈很容易发生失超.如何对快速交变脉冲磁场下的超导线圈进行有效的失超检测,这在世界上也无先例可循.EAST装置的失超检测系统经过几十轮单饼超导线圈实验及多轮装置正式放电实验后逐步建立和完善起来,并已通过工程验收满足了装置实验运行要求.本文主要介绍了EAST装置失超检测系统的基本结构和检测原理,重点阐述了极向场超导磁体失超检测的设计方法及实验结果。 相似文献
126.
本文利用脉冲激光沉积技术在SrTiO_3单晶衬底上生长了Sb掺杂BaSnO_3(BSSO)外延薄膜.结构和输运性质测量结果显示BSSO薄膜是一种具有立方钙钛矿结构导电性很好的薄膜材料,80K时呈现金属绝缘体转变,室温下薄膜的电阻率、载流子浓度和迁移率分别为ρ=2.43 mΩcm,n=1.65×1021 cm~(-3)和μ=1.75 cm~2/Vs.以BSSO薄膜为底电极制备了具有比较好电滞回线的Pb(Zr_(0.52)Ti_(0.48))O_3和Bi(Mn_(0.05)Fe_(0.95))O_3铁电电容器,表明BSSO薄膜是一种具有应用前景的新型电极材料. 相似文献
127.
<正>Lower tropospheric water vapor measurements are performed at nighttime using the mobile atmosphere monitoring lidar-2(AML-2) which is operated by the Anhui Institute of Optics and Fine Mechanics.In this lidar system,a 354.7-nm light from a Nd:YAG laser is used as stimulating source,whose Raman shifted center wavelengths are at 386.7 and 407.5 nm for nitrogen and water vapor,respectively.We present a novel and convenient method for determining the Raman lidar calibration constant according to the scanning performance of this lidar.We are likewise able to realize the measurement of water vapor profile in the low troposphere.The error induced by the uncertainty of calibrated constants is within 7% for the Raman lidar system.Experimental results from two months of study indicate that the method of calibrating the lidar system constant is feasible,and the Raman lidar performance is stable and reliable. 相似文献
128.
129.
Yucheng Wu Jiaqin Liu Rujun Xue Guozhong Wang Lide Zhang Faculty of Materials Science Engineering Hefei University of Technology Hefei P. R. China Institute of Solid State Physics Chinese Academy of Sciences Hefei P. R. China 《中国颗粒学报》2005,3(3)
This paper presents the preparation of ultrafine powders of Fe3O4 and Ni by a chemical method, followed by mixing the prepared powders with mica and other ultrafine powders for synthesizing microwave absorption coatings. The microwave attenuation rate of the coatings was measured by the Microwave Network Analyzer in the frequency range of 8-12 GHz at room temperature. The results indicate that microwave could be absorbed by the coatings with an effectiveness strongly dependent on the powder sort and content and the coating thickness. 相似文献
130.
WANG WeiXian ZHOU Fang TAN Shun WU Huan & ZHANG YuHeng National High Magnetic Field Laboratory University of Science Technology of China Hefei China National Laboratory for Superconductivity lnstitute of Physics the Center for Condensed Matter Physics Chinese Academy of Sciences Beijing China 《中国科学G辑(英文版)》2007,(2)
In the strict sense, it is not very clear why with magnetic field increasing, the normal-superconductive (NS) transition becomes broad for Bi2Sr2CaCu208+δ(Bi2212) while the NS transitions are almost parallel for La193Sroo7Cu04+δ(La214). In this paper, R-T relations are measured by the six-probe method. We propose a moving mechanism of the pancake vortex and vortex line for Bi2212. The theoretical curves fit the experiment data well. 相似文献