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601.
During the past years, there have been a lot of interests in the research of carbonaceous material as anode in lithium ion batteries1-3. Among them, natural graphite seems to be the most promising candidate for anode in lithium-ion batteries in terms of economy. Figure 1 The effect of Different Contents Figure 2 The Effect of Reacting Timeof Mixed Acid on Interlayer Distance On Interlayer DistanceHowever the raw natural graphite cannot be used for commercial purposes, because during proc…  相似文献   
602.
Alternating copolymerization of (-olefins with carbon monoxide (CO) catalyzed by cationic palladium-chiral ligand complexes is of great interest due to the potential use of the resulting polymer as a new material1. Recently, enantioselective alternating copolymerization of CO with styrene has been reported by us using PdCl_2-CuCl2-chiral phosphine catalyst2. Here, we first report enantioselective alternating copolymerization of CO with propylene (P) using [(DDPPI)Pd(CH3CN)4](BF4)2 as …  相似文献   
603.
12-Methoxypodocarpane-8,11,13-triene 1 is the key intermediate for synthesis of some important diterpenoids, such as Ferruginol 21, 6,7-dehydroferruginol 31, sugiol 42, 5-epixanthoperol 53 etc. These compounds posses significant bioactivities, such as fungicidal1, antimicrobial1 and cytotoxic activity2. Some methods of synthesis of the title compound 1 were reported, but the process is laborious and the yield is low. In connection with our effort to discovery and develop new anti-HIV drugs, …  相似文献   
604.
Co-Pd bimetallic catalysts immobilized with four kinds of resins with different specific areas were prepared by means of the solvated metal atom impregnation (SMAI) method. The results of the XRD and the magnetic measurement showed that as the specific area of the resin increased, the particle sizes of Co and Pd on the catalysts with the same metal content decreased, so the catalytic activity of the catalysts for the hydrogenation of diacetone alcohol as well as the reduction of oxygen on the fuel cell electrode increased. Below 140 , the conversion of diacetone alcohol increased as the reaction temperature increased, and above 140 , the conversion decreased because of the rupture of the resin.  相似文献   
605.
A compound {[Co(azpy)_2(NCS)_2]·1/4EtOH·1/2H_2O}_n(1), where azpy=4,4'-azobispyridine, was synthesized and characterized by means of IR, TGA-DTA, magnetic susceptibility and X-ray single crystal diffraction. It consists of two independent sets of fully interlocked two-dimensional networks with the dihedral angle 61.7°, organized in parallel stacks of the sheets which are made of edge-shared [Co(Ⅱ)]_4 squares separated by 0. 9062nm, and defined size rhombic channels. The thermal gravimetric analysis indicates that the framework is stable up to 198℃. The variable-temperature magnetic susceptibility measurements indicated that there is a weak antiferromagnetic interaction between the cobalt(Ⅰ) ions in the complex (1).  相似文献   
606.
IntroductionBioinformatics is coming with Human GenomeProject(HGP) . With the explosions of sequence,structural and other information available ,bioinformatics is playing an increasingly large rolein the study of fundamental biomedical problems.At present and in the near future,it is the mainchallenge for bioinformatists to make gene dicoveryand annotation of human genome sequences whenthe vast amount of data is produced by the highthroughput genome sequencing in a large scale andautomated m…  相似文献   
607.
IntroductionInclusioncompoundshavebeennotedinrecentyearsandresorcinol typecalix [4 ]arenehasbeenstudiedfortheirinclusionabilitiesbyScheiderandBugleretal[1— 3] .Thepolyolmoietiesincalix[4 ]re sorcinareneformrigidhydrogen bondingnetworks[4 ] ,andcalix [4 ]resorcinare…  相似文献   
608.
IntroductionSince Wilson and co- workers successfullysynthesized three- dimensional microporousaluminophosphates (Al PO4 - n ) [1] in the 1 980 s,much attention has been focused on the explorationof1 - D chain,2 - D layer and3 - D open- frameworkmetal phosphates from aqueous or non- aqueoussystems.The number of metals incorporated intothe frameworks of these materials is continuouslyincreasing and the metals include Be[2 ] ,Ga[3] ,In[4 ] ,Sn[5] ,Sb[6 ] ,and the transition metals Zn[7] ,Ni…  相似文献   
609.
IntroductionThe recent development of free radical biologyand medicine has provided a great deal of clinicaland experimental evidence indicating that the freeradical induced peroxidation of membrane lipids isassociated with a variety of chronic healthproblems,such as cancer,atherosclerosis andageing[1,2 ] . Both natural and synthetic antioxidantshave been used to trap peroxyl radicals and/orinitiating radicals to protect the membrane lipidsagainst free radical chain reactions,and hence mayhave…  相似文献   
610.
Precolumn derivatization is the most widely used means to overcome the detection problem in capillary electrophoresis. However most of the adopted reactions in carbohydrate labeling are time-consuming and not very selective, leading to lots of byproducts produced. We have thus tried to explored hydrazino-containing reagents which have been applied to TLC1,2 and HPLC2~5 with quite successfulness. Perez and Colón6 have also reported that dansylhydrazine can be used in CE-LIF of sugars. Th…  相似文献   
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