全文获取类型
收费全文 | 506篇 |
免费 | 49篇 |
国内免费 | 81篇 |
专业分类
化学 | 530篇 |
力学 | 7篇 |
综合类 | 5篇 |
数学 | 20篇 |
物理学 | 74篇 |
出版年
2023年 | 2篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2014年 | 32篇 |
2013年 | 48篇 |
2012年 | 44篇 |
2011年 | 7篇 |
2010年 | 2篇 |
2009年 | 4篇 |
2008年 | 21篇 |
2007年 | 19篇 |
2006年 | 17篇 |
2005年 | 19篇 |
2004年 | 28篇 |
2003年 | 35篇 |
2002年 | 85篇 |
2001年 | 193篇 |
2000年 | 31篇 |
1999年 | 20篇 |
1998年 | 10篇 |
1997年 | 8篇 |
1996年 | 1篇 |
1995年 | 3篇 |
排序方式: 共有636条查询结果,搜索用时 0 毫秒
631.
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
632.
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
633.
WU Shi-hua* * WEI Wei ZHU Chang-ying HUANG Wei-pingZHANG Shou-min ZHENG Xiu-cheng ZHANG Shu-hong ZHAO Wei-jun 《高等学校化学研究》2001,17(4):439-444
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
634.
IntroductionAmrinon,asyntheticbipyridinederivative,nonglycosideandnoncatecholaminecar-diotonicstimulant,iscurrentlyusedinthetreatmentoftheheartfailureandforcardiovascu-larsupportinpediatricpatients.Itpossessespotentcardiacandbloodvesselspreadingef-fe… 相似文献
635.
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
636.
基于近红外腔衰荡光谱技术(CRDS)结合闪光光解,搭建了一套用于瞬态自由基探测的高灵敏度实验装置。通过扫描自主设计的光学谐振腔腔长,实现激光器与腔的模式耦合,基于线性回归求和(LRS)算法对衰荡曲线进行拟合,获得衰荡时间,在20.3 km有效光程和6.25 s采集时间下,系统可实现5.05×10–11cm–1的探测灵敏度。使用266 nm Nd:YAG激光器光解臭氧(O3)和乙炔(C2H2)的混合物产生氢过氧自由基(HO2·),测量了HO2·在6638.203 cm–1位置处的特征吸收,获得了分辨率为0.002 cm–1的吸收光谱。在2 kPa条件下,通过测量HO2·自反应的衰变获得了6638.203 cm–1处HO2·的吸收截面(σ)为3.3×10–19cm2/molecule,对应的吸收谱线强度(S)... 相似文献