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131.
同步辐射光源具有宽光谱、高亮度、高准直等优异性能,被广泛地用于高压科学研究。在依托同步辐射光源所发展的诸多高压研究手段中,X射线衍射是最基本的也是应用最多的实验技术之一。本文简单介绍了同步辐射光的独特性能和光源的基本构成,以及同步辐射光束线和实验站的基本概念。针对基于金刚石对顶砧(DAC)的高压X射线衍射技术,阐述了多种测试方法的原理和应用,包括粉末衍射、单晶衍射、多晶衍射、径向衍射、激光加温衍射以及快速加载衍射等。对北京同步辐射装置(BSRF)4W2高压衍射线站所提供的同步辐射光品质、X射线微聚焦能力、多种衍射方法以及新近发展的实验技术进行了较详细的描述,并展望了高能同步辐射光源(HEPS)的建设给高压科学研究带来的机遇。 相似文献
132.
COOEtCOCH3(CH3)2NNHNH2NNCH3OOEtNH2NH2NNCH3ONHNH2PhNCSNNCH3ONHNHCNHSOH-NNCH3NNHNPhS12345 1 INTRODUCTION A large number of 1,2,4-triazole derivatives have been synthesized in recent years[1~4]. Many of them are reported to exhibit broad spectrum biologi-… 相似文献
133.
1 INTRODUCTION Due to their variability in binding modes, five- membered heterocyclic ligands such as pyrazole[1] and 1,2,4-triazole[2] have been drawn much attention. Consequently, there are numerous reports on their derivatives. Imidazoles resemble pyrazoles, and they are isomeric five-membered heterocyclic molecules containing two nitrogen atoms. Furthermore, imida- zole is also a ring component of adenine and purine, one of the most versatile binding sites in biological systems, so th… 相似文献
134.
1 INTRODUCTION The cadmium(??) complexes have been exten-sively studied because of their potentially usefulproperties, such as toxicity research[1], catalysis[2],magnetism[3] and nonlinear optics[4]. A lot of studieson binuclear cadmium(??) pendant-ar… 相似文献
135.
Phase Transition of Graphitic-C3N4 under High Pressure by In Situ Resistance Measurement in a Diamond Anvil Cell 下载免费PDF全文
In situ resistance measurement of Graphitic-C3N4 has been performed under high pressure in a diamond anvil cell. The result reveals that there are changes of electron transport behaviour. As the pressure increases from ambient to 30 GPa, three abnormal resistance changes can be found at room temperature and two are found at 77K. The abnormal resistance dropped at 5 GPa is close to the phase transition pressure from the P6m2 structure to the p structure predicted by Lowther et al. [Phys. Reg. B 59 (1999) 11683] Another abnormal change of resistance at 12 GPa is related to the phase transition from g-C3N4 to cubic-C3N4 [Teter and Hemley, Science 271 (1990) 53]. 相似文献
136.
本文通过真空蒸镀的方法,制备了以二(1-萘基){4-[2-(3-二腈基亚甲基-5,5-二甲基-1-环己烯基)乙烯基]苯基}胺(DNP-2CN)作为电子给体,富勒烯(C60)作为电子受体的有机光电池器件,并引入10 nm厚度的三(8-羟基喹啉)铝(Alq3)作为缓冲层。在模拟太阳光(AM1.5, 75 mW·cm-2)下,基于DNP-2CN制备的太阳能电池的开路电压为370 mV,短路电流密度为0.61 mA·cm-2,光电转换效率为0.09%。 相似文献
137.
1 INTRODUCTION The aconitum plants produce various diterpene and norditerpene alkaloids[1, 2]. Up to now more than 450 diterpenoid and norditerpenoid alkaloids have been isolated from the roots of this genus[3]. Sub- sequent studies on the flower of the same subspecies were directed to the other secondary metabolites such as flavonoids[4, 5]. The flavonoidic composi- tions of several oriental species of A. plants have been reported[6~8]. A. sungpanense hand. Mazz., a very highly poi- s… 相似文献
138.
WU Rui-Fenga b ZHANG Tong-Laia② QIAO Xiao-Jinga ZHANG Jian-Guoa YANG Lia YU Weia a 《结构化学》2006,25(7):849-853
1 INTRODUCTION Napthalene-1,4-dicarboxylate acid (1,4-NDC) has rigidity and stability because of the aryl ring and flexibility due to the carboxyl group, so it can be designed to assemble many novel microporous me- tal-organic coordinate polymer materials (MOCP) with transition metal[1~5]. In order to design and syn- thesize MOCP with specific framework structure for potential applications as functional materials, the ligand was decorated by bringing more substitutes to the aryl ring[… 相似文献
139.
1 INTRODUCTION Schiff base complexes containing sulfur and com- plexes of amino acid Schiff bases[1~5] have recently aroused increasing interest because of their antiviral, anticancer and antibacterial activities. Taurine, an amino acid containing sulfur, is indispensable to human beings and has important physiological func- tions. Recently, we have found that the Shiff base derived from taurine has manifold coordination modes[4~10]. Aromatic-ring stacking interaction is an important … 相似文献
140.
A new dinuclear copper complex, [Cu(C13H9N2O)Cl]2·(CH3CN)2 (C30H24Cl2Cu2N6O2), has been synthesized and characterized by X-ray structure determination. It crystallizes in the tricli- nic system, space group P1, with a = 7.6677(14), b = 9.2375(17), c = 11.227(2) , α = 81.338(3), β = 88.173(4), γ = 66.199(3)o, V = 718.9(2) 3, Z = 1, Mr = 698.53, F(000) = 354, Dc = 1.613 g/cm3, μ(MoKα) = 1.705 mm-1, the final R = 0.0645 and wR = 0.1364 for 2474 unique reflections with 1809 observed ones (I > 2σ(I)). In the title complex, each copper(II) atom is located at the center of a distorted tetrahedron consisting of four coordinate atoms (one nitrogen atom, two oxygen anions, and one chlorine atom). Two copper(II) atoms are bridged by two oxygen anions (O(1) and O(1a)) of two phenolates to form a Cu(II)–Cu(II) binuclear entity, and the distance between two copper(II) atoms is 3.0144(15) . 相似文献