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1.
~~Formation of α,α'-Bis(substituted benzylidene)cycloalkanones from Masked Aldehydes Promoted by Samarium(III) Triiodide~~ 相似文献
2.
Jing Lin CHEN Gang Qiang YIN Zhong Ning CHEN* State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Fuzhou 《中国化学快报》2003,(5)
Great attention is currently paid to the synthesis of polynuclear transition metal complexes as well as their photochemical, photophysical, and electrochemical properties. The design of multicomponent systems capable of performing useful light- and/or redox-induced function is of special interest1. The oxo-centered carboxylate-bridge trinuclear ruthenium clusters have been investigated extensively during recent decades because they have remarkable electron-transfer properties, intense visibl… 相似文献
3.
Jing Ping WANG Qiang WU Jing Yang NIU* School of Chemistry Chemical Engineering Henan University Kaifeng 《中国化学快报》2002,13(9):915-918
It is becoming a focus to synthesize and assemble organic-inorganic materials, especially, to synthesize charge-transfer complexes formed by polyoxometalate and organic donors. They have attracted much attention because such complexes are active in their electric, magnetic and optic properties1-4, many investigations about them have been done and some crystal structures of them were reported5-6. But, the disadvantage of these crystals is instability at room temperature. According to the view… 相似文献
4.
1 引 言烷基膦酸 O 烷基酯是禁止化学武器公约禁控化学品附表中一类重要的化合物。这类化合物的结构中有 3个烷基基团 ,进行组合搭配后可产生多种同分异构体。因此 ,化学武器履约核查时很难对这类化合物进行分离并作出明确鉴定。异丙基膦酸二正丙酯和异丙基膦酸乙基丁基酯是一对同分异构体 ,是国际联试中由中国提供的样品 ,性质非常相似 ,普通方法很难分离。本文利用GC Tracer FTIR仪器Tracer接口的ZnSe片可移动的特点 ,优化色谱条件 ,实现了两化合物的完全分离。同时通过联合运用红外光谱鉴定其结构 ,获得了满意的结果。2 实验… 相似文献
5.
Structural Features of a Polysaccharide from Centella asiatica 总被引:3,自引:0,他引:3
Xue Song WANG Jin You DUAN Ji Nian FANG* Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 《中国化学快报》2004,15(2):187-190
Centella asiatica has been used as remedy for sodation, stabilization and against lepra, anabrosis1 in the oriental countries. The low-molecular-weight constituents in Centella asiatica have been investigated1. However, no polysaccharides have been reported. 1BI was the first polysaccharide isolated from C. asiatica, which had immunostimulating activity in vitro. In present study, we report the structural features of 1BI. Experimental Extraction, isolation and purification Dried C.… 相似文献
6.
Thermal decomposition kinetics of titanium hydride and Al alloy melt foaming process 总被引:3,自引:0,他引:3
YANG Donghui* HE Deping*& YANG Shangrun* . Department of Materials Science Engineering Southeast University Nanjing China . Department of Chemistry Nanjing University Nanjing China 《中国科学B辑(英文版)》2004,47(6):512-520
Metal foams, now one of research foci, are a newclass of materials with low densities and novel physi-cal, mechanical, thermal, electrical and acoustic prop-erties[1—8]. Demands from high-tech make Al alloyfoam, which has much higher specific strength than ofpure Al foam, the new development focus[9—11]. Melt foaming process is one of the approaches tofabricate Al foam and Al alloy foam and their porestructure (pore diameter and porosity) has close rela-tionship with the thermal decompo… 相似文献
7.
采用燃烧法合成了CeO2:Er纳米荧光粉,研究了不同粒径大小的CeO2:Er的晶型和晶貌并对该现象进。TEM结果表明无定形CeO2:Er包围着纳米晶CeO2:Er,可起到表面修饰的作用。光声光谱在保持纳米材料表面状态不改变的前提下,分析了不同粒径的CeO2:Er的光谱性质,解释了随纳米粒径减小CeO2光谱峰吸收峰有蓝移而Er^3 没有明显谱峰位移的原因。在荧光光谱中,发现小粒径的CeO2:Er有较大的红绿发射比,行了解释。 相似文献
8.
XU Long Ya * WANG Qing Xia LIN Li Wu XU Yi De Dalian Institute of Chemical Physics The Chinese Academy of Sciences Dalian Liaoning 《天然气化学杂志》1998,7(1):7-15
Ni/Si2催化剂具有较好的低碳烷烃与二氧化碳重整制合成气的反应性能,添加La2O3助剂和K2O助剂可提高催化剂活性和合成气收率,从而进一步改善催化剂的低碳烷烃与CO2重整制合成气的反应性能,研制的KLaNi/Si2催化剂,用于天然气与CO2重整反应制合成气可达97%的低碳烷烃转化率和95%以上的合成气收率。 相似文献
9.
Jun JIA Xing Wang WANG Yi Li ZHAO Yu ZHU Jing Chao TAO* Department of Chemistry Zhengzhou University Zhengzhou Chemical Engineering Institute of Henan Province Zhengzhou 《中国化学快报》2004,15(3):292-295
Proteins containing dinuclear Cu (II), Zn (II) centers play paramount roles in biology1. As mimetic of metal-dependent esterase, dinuclear Cu (II) and Zn (II) complexes have received a great deal of attentions2~6. They are of interest in the field of biomimetic chemistry to provide an improved understanding of the function of the biological sites and as potential catalysts for substrate oxidations. Schiff base type polydentate ligands which contain centeral hydroxyl group have been wid… 相似文献
10.
Xiao Long WANG Jian Peng FENG Xin Gang XIE Xiao Ping CAO* Xin Fu PAN* Department of Chemistry & State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2004,(9)
Aiphanol was isolated from the seeds of Aiphanes aculeate Willd. (Arecaceae) collected in Peru and was reported to exhibit significant inhibitory activities against cyclooxyge- nases-1 and -2. The structure of aiphanol was elucidated by spectroscopic methods as an unprecedented stilbenolignan skeleton in which a stilbene moiety is linked to a phenylpropane unit through a dioxane bridge1. In our previous works the synthetic approach to 1,4-benzodioxane lignans were achieved2. Since aiphanol… 相似文献