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101.
Two new complexes (Cp)2Ti(Sal)2 and(Cp)2Ti(Clo)2(Cp=Cyclopentadienyl η5-C5H5), have been synthesized in anhydrous THF by the reaction of Hsal(o-hydroxybenzoic acid, salicylate acid) or Hclo[N-(m-chloro-phe-nyl) anthranili acid, acidum clofenamicum] with (Cp)2TiCl2 and characterized by means of elemental analyses, IR, 1H NMR, 13C NMR, UV and molar conductivity. In complex (Cp)2Ti(Sal)2 or (Cp)2Ti(Clo)2, the oxygen atom of the carboxyl group coordinates to Ti(IV) in a monodentate manner. The inhibitory action of the complexes on mouse ear tumefaction caused by croton oil and rat foot granulation growth caused by cotton balls is higher than that of the corresponding ligands Hsal, Hclo and [(Cp)2TiCl2], whereas their toxicity is lower than those of the free ligands. 相似文献
102.
Fullerenes C60 and C70 have high electron affinity ( 2.6 - 2.8 ev ) and readily form anions on electronchemical reduction1, which were famous as electron acceptor in photo-excitation because of symmetrical shape, large size, and properties of its p - electron system2. After observation of molecular ferromagnetism3 in the tetrakis (dimethylamino ) ethylene salt of C60 as well as the occurrence of ultra-fast photoinduced electron transfer within the dimethyl aniline - C60 complex4, prompted us… 相似文献
103.
He Ping ZENG 《中国化学快报》2002,13(12)
Photoinduced electron transfer processes between fullerenes (C60 / C70) and N, N, N′, N′- tetra - ( p-methylphenyl ) - 4, 4′- diamino - 1, 1′- diphenyl ether ( TPDAE ) have been studied by nanosecond laser flash photolysis. Quantum yields and rate constants of electron transfer from TPDAE to excited triplet state of fullerenes (C60 / C70 ) in benzonitrile have been evaluated by observing the transient absorption bands in the near-IR region where the excited triplet state, radical anion of fullerenes ( C60 / C70 ) and radical cations of TPDAE appear. 相似文献
104.
Novel macrocyclic monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a-5a were synthesized by the reaction of calix[4]arene dibromides 1-5 with the disodium salt of bis(2-selenylethyl)ether in the yields between 28% and 64%. Their structures were characterized by proton and carbon NMR spectra. X-Ray structure analysis of la further confirmed the cone conformation of compounds 1a-5a. An interesting host-guest complex of la with dichloromethane via CH/π and C1/π interactions was elucidated. Extraction experiments showed that these novel monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a-5a had strong extraction ability towards mercury ion. The interaction of Hg^2+with the calix ligand has also been investigated by 1^H NMR titration. 相似文献
105.
OFDM(正交频分复用)是第4代移动通信系统的核心技术之一,在OFDM基本系统中,各载波间正交性的损失会导致ICI(载波间干扰)的产生。文中在介绍和比较多种传统消除ICI的方法的基础上,提出了一种新的ICI消除技术:PTS(部分传输序列)法和SLM(选择映射)法,并针对PTS算法的缺陷提出了改进优化算法。仿真结果表明PTS和SLM算法都能减小系统的ICI,对系统误码率有所改善,从而使系统的性能得到了提高。 相似文献
106.
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108.
设计合成了2-[(2'-芴基)-乙烯基]-8-羟基喹啉(6)、2-[(2'-菲基)-乙烯基]-8-羟基喹啉(7)及其金属锌配合物8和9; 用UV-Vis, FT-IR, ESI-MS, 1H NMR和元素分析确认了化合物6和7的结构; 并用四甲基偶氮唑盐微量酶反应比色法(MTT法)研究了其调控骨髓间质干细胞增殖的作用, 结果表明, 化合物6和7对干细胞有明显的增殖作用. 用FT-IR, FAB-MS和元素分析表征了金属锌配合物结构, 光致发光光谱测试结果表明, 化合物8的发光峰值为602 nm, 发黄光; 化合物9的发光峰值为628 nm, 发橙红色光. 相似文献
109.
In this paper,eight 4-(1,2,4-triazole-5-yl) furazan (TZFZ) derivatives were designed,and the molecular configurations of TZFZ compounds were optimized by using the B3LYP/6-311+G*level.Meanwhile,the detonation performance,density,impact sensitivity,heat of formation and oxygen balance have been investigated.The results clearly and intuitively illustrate that the introduction of-NO_2 and coordination oxygen plays a pivotal role in increasing the density and heat of formation.In summary,the properties of these compounds are better than the traditional explosives RDX and TNT,especially the density and detonation pressure.Energetic evaluations showed that compounds B1 (P=36.73 GPa;D=8.98 km·s~(-1),ρ=1.88 g·cm~(-3))and B7 (P=38.51 GPa;D=9.17 km·s~(-1),ρ=1.90 g·cm~(-3)) could be seen as promising candidates of energetic insensitive compounds with remarkable performance. 相似文献
110.
分布式视频编码器中Turbo码纠错所需要的校验位数量直接决定整个编码器的率失真(RD,Rate-Distortion)性能.分析了传统算法的次优化问题,提出一种新的基于比特概率优化的信道似然值计算算法,该算法首先将原始像素进行比特面分解,然后分别对每个比特面进行独立Turbo码编码及联合解码.解码端在已知已解码比特面的条件下,计算当前解码比特面更准确的信道似然值作为Turbo码的解码输入,减少解码所需要传输的校验位数量,提高编码器RD性能.实验结果表明所提算法能明显提升编码系统的RD性能. 相似文献