全文获取类型
收费全文 | 386篇 |
免费 | 2篇 |
专业分类
化学 | 263篇 |
晶体学 | 1篇 |
力学 | 4篇 |
数学 | 31篇 |
物理学 | 89篇 |
出版年
2022年 | 3篇 |
2021年 | 3篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 7篇 |
2013年 | 12篇 |
2012年 | 9篇 |
2011年 | 8篇 |
2010年 | 2篇 |
2009年 | 6篇 |
2008年 | 18篇 |
2007年 | 17篇 |
2006年 | 13篇 |
2005年 | 12篇 |
2004年 | 5篇 |
2003年 | 10篇 |
2002年 | 44篇 |
2001年 | 19篇 |
2000年 | 25篇 |
1999年 | 22篇 |
1998年 | 8篇 |
1997年 | 11篇 |
1996年 | 11篇 |
1995年 | 20篇 |
1994年 | 21篇 |
1993年 | 16篇 |
1992年 | 9篇 |
1991年 | 4篇 |
1990年 | 7篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1971年 | 2篇 |
1969年 | 2篇 |
1932年 | 1篇 |
排序方式: 共有388条查询结果,搜索用时 93 毫秒
381.
JM Chatterjee M Saha Sarkar S Bhattacharya P Banerjee S Sarkar RP Singh S Murulithar RK Bhowmik 《Pramana》2001,57(1):165-169
High-spin states of 95,97Mo (Z=42, N=53,55) nuclei have been investigated through 82Se(18O, xn) reaction at Eb=60 MeV. The level scheme in 95Mo has been observed upto ≏ 10 MeV in the present experiment. The level structure shows mainly single particle character.
In 97Mo, the ground state level sequence has been extended to ≏ 4.5 MeV while the previous information had been up to 2.4 MeV.
A negative parity band built on 1437 keV (11/2−) excited state has been extended to 5.5 MeV. The structure seems to show a coexistence of single particle and collective
modes of excitation. Properties of both the nuclei have been compared with shell model calculations using OXBASH. 相似文献
382.
The life and contributions to various areas of chemistry of German chemist Friedrich Wöhler (1800–1882) are briefly sketched. His serendipitous synthesis of urea from ammonium cyanate in 1828, which is dealt with in some detail, challenged the vitalistic theory that organic compounds can be produced only by living organisms and led to todays synthetic chemical industry and its host of products that we take for granted. 相似文献
383.
Background
Clinical spinal cord injury in domestic dogs provides a model population in which to test the efficacy of putative therapeutic interventions for human spinal cord injury. To achieve this potential a robust method of functional analysis is required so that statistical comparison of numerical data derived from treated and control animals can be achieved. 相似文献384.
George B. Kauffman 《The Chemical Educator》1999,4(6):242-258
Ever since receiving the 1993 ACS Pimentel Award in Chemical Education (Figure 1), I have been interested in the life and achievements of the Fresno-born, larger-than-life figure after whom the award was named. The year 1999 provides an especially appropriate occasion to recall Pimentels personal and professional career, for it is the tenth anniversary not only of his death but also of National Chemistry Week, the expanded form of National Chemistry Day, the popular American Chemical Society outreach program that he originated. 相似文献
385.
Kline JL Glenzer SH Olson RE Suter LJ Widmann K Callahan DA Dixit SN Thomas CA Hinkel DE Williams EA Moore AS Celeste J Dewald E Hsing WW Warrick A Atherton J Azevedo S Beeler R Berger R Conder A Divol L Haynam CA Kalantar DH Kauffman R Kyrala GA Kilkenny J Liebman J Le Pape S Larson D Meezan NB Michel P Moody J Rosen MD Schneider MB Van Wonterghem B Wallace RJ Young BK Landen OL MacGowan BJ 《Physical review letters》2011,106(8):085003
The first soft x-ray radiation flux measurements from hohlraums using both a 96 and a 192 beam configuration at the National Ignition Facility have shown high x-ray conversion efficiencies of ~85%-90%. These experiments employed gold vacuum hohlraums, 6.4 mm long and 3.55 mm in diameter, heated with laser energies between 150-635 kJ. The hohlraums reached radiation temperatures of up to 340 eV. These hohlraums for the first time reached coronal plasma conditions sufficient for two-electron processes and coronal heat conduction to be important for determining the radiation drive. 相似文献
386.
Wishka DG Bédard M Brighty KE Buzon RA Farley KA Fichtner MW Kauffman GS Kooistra J Lewis JG O'Dowd H Samardjiev IJ Samas B Yalamanchi G Noe MC 《The Journal of organic chemistry》2011,76(6):1937-1940
To facilitate a drug discovery project, we needed to develop a robust asymmetric synthesis of (2S,5S)-5-substituted-azepane-2-carboxylate derivatives. Two key requirements for the synthesis were flexibility for elaboration at C5 and suitability for large scale preparation. To this end we have successfully developed a scalable asymmetric synthesis of these derivatives that starts with known hydroxy-ketone 8. The key step features an oxidative cleavage of aza-bicyclo[3.2.2]nonene 14, which simultaneously generates the C2 and C5 substituents in a stereoselective manner. 相似文献
387.
Nykter M Price ND Larjo A Aho T Kauffman SA Yli-Harja O Shmulevich I 《Physical review letters》2008,100(5):058702
Network structure strongly constrains the range of dynamic behaviors available to a complex system. These system dynamics can be classified based on their response to perturbations over time into two distinct regimes, ordered or chaotic, separated by a critical phase transition. Numerous studies have shown that the most complex dynamics arise near the critical regime. Here we use an information theoretic approach to study structure-dynamics relationships within a unified framework and show that these relationships are most diverse in the critical regime. 相似文献
388.
Fabrício RS Pereira Andréa Alessio Maurício S Sercheli Tatiane Pedro Elizabeth Bilevicius Jane M Rondina Helka FB Ozelo Gabriela Castellano Roberto JM Covolan Benito P Damasceno Fernando Cendes 《BMC neuroscience》2010,11(1):1-13