全文获取类型
收费全文 | 288篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
化学 | 240篇 |
晶体学 | 3篇 |
力学 | 2篇 |
数学 | 4篇 |
物理学 | 40篇 |
出版年
2022年 | 4篇 |
2021年 | 3篇 |
2018年 | 4篇 |
2015年 | 4篇 |
2014年 | 2篇 |
2013年 | 15篇 |
2012年 | 11篇 |
2011年 | 19篇 |
2010年 | 6篇 |
2009年 | 6篇 |
2008年 | 23篇 |
2007年 | 11篇 |
2006年 | 17篇 |
2005年 | 15篇 |
2004年 | 13篇 |
2003年 | 7篇 |
2002年 | 10篇 |
2001年 | 6篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1997年 | 4篇 |
1995年 | 4篇 |
1994年 | 8篇 |
1993年 | 2篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 1篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 8篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1979年 | 4篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1973年 | 4篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1967年 | 1篇 |
1958年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有289条查询结果,搜索用时 15 毫秒
91.
92.
93.
Shindo K Osawa A Nakamura R Kagiyama Y Sakuda S Shizuri Y Furukawa K Misawa N 《Journal of the American Chemical Society》2004,126(46):15042-15043
The comprehensive bioconversion of aromatic compounds with a benzene ring to a picolinic acid was achieved with a recombinant Escherichia coli strain that expressed the six genes involved in biphenyl catabolism, these being the bphA1(2072)A2A3A4 genes encoding the evolved biphenyl dioxygenase, the bphB gene encoding dihydrodiol dehydrogenase, and the bphC gene encoding catechol 2,3-dioxygenase. 相似文献
94.
Molecules adsorbed on Pt nanoparticles prepared on Si by a chemical deposition technique exhibit extremely strong IR absorption, which enables fast time-resolved IR monitoring of electrocatalytic reactions. 相似文献
95.
K Umetsu M Tanaka I Yuasa N Saitou I Takeyasu N Fuku E Naito K Ago N Nakayashiki A Miyoshi S Kashimura G Watanabe M Osawa 《Electrophoresis》2001,22(16):3533-3538
A number of mutations in coding and noncoding regions of mitochondrial DNA (mtDNA) have previously been studied. In the present study, we simultaneously typed six mutation sites in the coding region by use of amplified product-length polymorphism (APLP) analysis. The mtDNA variations of 2471 individuals from 20 populations of Japanese, Korean, Chinese, and German were examined and classified into 18 haplotypes. Two of these haplotypes, B1 (estimated ancestral haplotype) and C1, were distributed among all populations tested. However, the haplotypes A1, A2, B2, B3, and C2 were mostly restricted to the Mongoloid populations, whereas haplotypes B5 and C5 appeared almost exclusively in the German population. Phylogenetic analysis by the neighbor-joining method revealed that the Japanese populations were more closely related to each other than to the other East Asian populations surveyed. The multiplex APLP method is suitable for large-scale screening studies of mtDNA variability because it is both rapid and economical. 相似文献
96.
The adsorption of pyrazine at a polycrystalline Au film electrode has been investigated using in situ surface-enhanced infrared absorption spectroscopy (SEIRAS), chronocoulometry, and ac impedance. Combining the SEIRA data and the thermodynamic data (the surface charge density of the electrode and the relative Gibbs surface excess of pyrazine), pyrazine was found to adsorb on the surface with a vertical end-on configuration via one N atom. The SEIRA spectra were compared with published surface-enhanced Raman (SER) spectra of pyrazine in order to clarify the reason for the breakdown of the Raman selection rule in the SER spectra. The activation of originally Raman-forbidden modes in the SER spectra is well explained by a photo-driven charge-transfer mechanism. The charge-transfer is deduced to be from filled metal states near the Fermi level to the first and second excited states of pyrazine. It is emphasized that the comparative SEIRA and SER studies are important for a better understanding of the electrochemical interface. 相似文献
97.
98.
Zenjiro Osawa Mitsue Suzuki Yoshitaka Ogiwara Isao Sugaya Kiyoshi Hirama Takao Kasuga 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):275-285
Polymeric ultraviolet absorbers were prepared from 2-hydroxy-4-acryloyloxybenzophenone and 2-hydroxy-4-methacryloyloxybenzophenone and their inhibitive effect for photodegradation of polyethylene were examined by measuring mechanical strength, melt index, carbonyl group, and color difference. The polymeric ultraviolet absorbers were superior to the same type of ultraviolet absorber with low molecular weight in many properties, but inferior to Tinuvin, a commercial reagent, which has a different molecular structure. Therefore, within the ultraviolet absorbers examined, molecular structure seems to be a more important factor than molecular weight. 相似文献
99.
Magnesium carbenoids were generated from aryl 1-chloroalkyl sulfoxides with i-PrMgCl in THF at low temperature in quantitative yields. The magnesium carbenoids were found to be reactive with N-lithio alkylamines to afford an olefin, which was derived from dimerization of the magnesium carbenoid, in moderate yield. On the other hand, reaction of the magnesium carbenoids with N-substituted N-lithio arylamines gave non-stabilized α-amino-substituted carbanions in good yields. Reactivity of the α-amino-substituted carbanions with some electrophiles was investigated and it was found that ethyl chloroformate reacted to give α-amino acid derivatives in good yields. As a whole, a new method for one-pot, three-component combined synthesis of α-amino acid derivatives from aryl 1-chloroalkyl sulfoxides was realized. 相似文献
100.
The characteristics of the thiol—disulphide exchange reaction are examined by an ab initio MO method. It is shown that this exchange reaction proceeds via one transition state, with almost no conformational distortion. 相似文献