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841.
LI Bo * Yoshifumi KOIDE Kunio ESUMI . Toyota Central R & D Labs. Inc. Yokomichi Nagakute Aichi Japan . Departemnt of Applied Chemistry Institute of Colloid Interface Science Science University of Tokyo 《高等学校化学研究》2002,18(2):206-210
IntroductionInclusioncompoundshavebeennotedinrecentyearsandresorcinol typecalix [4 ]arenehasbeenstudiedfortheirinclusionabilitiesbyScheiderandBugleretal[1— 3] .Thepolyolmoietiesincalix[4 ]re sorcinareneformrigidhydrogen bondingnetworks[4 ] ,andcalix [4 ]resorcinare… 相似文献
842.
CHEN Wei YUAN Hong-ming JIANG Yu-sheng HUO Hua CHEN Jie-sheng *State Key Laboratory of Inorganic Synthesis Preparative Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2002,18(4):375-379
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
843.
Antioxidative Effect of Schiff Bases with o-Hydroxybenzylidene Groupon Free Radical Induced Hemolysis of Human Red Blood Cell 总被引:1,自引:0,他引:1
LUO Xu yang ZHAO Jian zhang LIN Ying jie LIU Zai qun * College of Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2002,18(3):287-289
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
844.
WANG Wei WANG Yu-hong Li Wei * *Biological Macromolecular Laboratory College of Life Science Jilin University Changchun P. R. China 《高等学校化学研究》2002,18(4):491-494
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
845.
利用双层流动反应管作为束源,研究了F与CH2Br2反应生成的CBr2和Br2的气相激光诱导荧光色散谱,将得到的谱线分别指定为CBr2的(0,13,0)→(0,v2″,0)(v2″=1~6)跃迁和Br2的 3Π+u→ 1Σ+g跃迁,从光谱中首次得到气相CBr2自由基基态弯曲振动频率ν2″=215 cm-1,实验确认了CBr2自由基和Br2是F+CH2Br2过程多步反应的产物. 相似文献
846.
IntroductionAmrinon,asyntheticbipyridinederivative,nonglycosideandnoncatecholaminecar-diotonicstimulant,iscurrentlyusedinthetreatmentoftheheartfailureandforcardiovascu-larsupportinpediatricpatients.Itpossessespotentcardiacandbloodvesselspreadingef-fe… 相似文献
847.
Cluster-assisted generation of multi-charged ions in nanosecond laser ionization of pulsed hydrogen sulfide beam at 1064 and 532nm 下载免费PDF全文
The multi-charged sulfur ions of Sq= (q\le 6) have been generated when hydrogen sulfide cluster beams are irradiated by a nanosecond laser of 1064 and 532,nm with an intensity of 1010\sim 1012W1\cdotcm-2. S6+ is the dominant multi-charged species at 1064nm, while S4+, S3+ and S2+ ions are the main multi-charged species at 532nm. A three-step model (i.e., multiphoton ionization triggering, inverse bremsstrahlung heating, electron collision ionizing) is proposed to explain the generation of these multi-charged ions at the laser intensity stated above. The high ionization level of the clusters and the increasing charge state of the ion products with increasing laser wavelength are supposed mainly due to the rate-limiting step, i.e., electron heating by absorption energy from the laser field via inverse bremsstrahlung, which is proportional to \lambda 2, \lambda being the laser wavelength. 相似文献
848.
Weinan E~* Jianfeng LU~ 《数学年刊B辑(英文版)》2007,28(6):665-676
The authors consider the simplest quantum mechanics model of solids,the tight binding model,and prove that in the continuum limit,the energy of tight binding model converges to that of the continuum elasticity model obtained using Cauchy-Born rule.The technique in this paper is based mainly on spectral perturbation theory for large matrices. 相似文献
849.
本研究利用原位合成法成功制备CeO2-WO3催化剂并用于脱硝反应,焙烧温度为550℃的CW-550催化剂活性最佳,200℃时CW-550脱硝活性达到90%以上。CW-550催化剂具有优越的催化剂性能可归结为较大的比表面积、较多的Ce3+物种、丰富的表面酸性和优越的氧化还原性能。Ce3+增多,有利于氧空位的形成,可促进氧化还原性能。WO3的引入,在550℃的焙烧条件下可显著提升催化剂的Br?nsted酸量,有利于氨气的吸附与活化,提升其催化性能。CW催化剂上吸附的NH3物种能与气态的NO反应,而吸附态的NH3与吸附态的NOx不能进行高效反应,因此,CW催化剂的SCR反应主要遵循Eley-Rideal反应机理。 相似文献