全文获取类型
收费全文 | 1477篇 |
免费 | 31篇 |
国内免费 | 2篇 |
专业分类
化学 | 1158篇 |
晶体学 | 6篇 |
力学 | 21篇 |
数学 | 54篇 |
物理学 | 271篇 |
出版年
2022年 | 8篇 |
2021年 | 10篇 |
2020年 | 12篇 |
2019年 | 20篇 |
2018年 | 11篇 |
2017年 | 8篇 |
2016年 | 20篇 |
2015年 | 20篇 |
2014年 | 30篇 |
2013年 | 83篇 |
2012年 | 69篇 |
2011年 | 78篇 |
2010年 | 38篇 |
2009年 | 36篇 |
2008年 | 81篇 |
2007年 | 73篇 |
2006年 | 79篇 |
2005年 | 85篇 |
2004年 | 63篇 |
2003年 | 78篇 |
2002年 | 60篇 |
2001年 | 44篇 |
2000年 | 27篇 |
1999年 | 20篇 |
1998年 | 10篇 |
1997年 | 18篇 |
1996年 | 11篇 |
1995年 | 8篇 |
1994年 | 21篇 |
1993年 | 9篇 |
1992年 | 28篇 |
1991年 | 22篇 |
1990年 | 29篇 |
1989年 | 18篇 |
1988年 | 16篇 |
1987年 | 16篇 |
1986年 | 23篇 |
1985年 | 34篇 |
1984年 | 14篇 |
1983年 | 14篇 |
1982年 | 14篇 |
1981年 | 15篇 |
1980年 | 17篇 |
1979年 | 14篇 |
1978年 | 12篇 |
1977年 | 15篇 |
1976年 | 13篇 |
1975年 | 12篇 |
1974年 | 7篇 |
1973年 | 11篇 |
排序方式: 共有1510条查询结果,搜索用时 15 毫秒
181.
Imura Y Tanuma H Sugimoto H Ito R Hojo S Endo H Morita C Kawai T 《Chemical communications (Cambridge, England)》2011,47(22):6380-6382
Straight ultrathin Au nanowires (NWs) with diameters less than 2 nm were synthesized using the lamellar structure of C18AA in an organogel and its selective adsorption for specific gold surfaces. In addition, the potential to form a bilayer structure with interdigitated hydrocarbon chains enabled the production of water-dispersible Au NWs without morphological change. 相似文献
182.
Yokoi T Sakuma J Maeda K Domen K Tatsumi T Kondo JN 《Physical chemistry chemical physics : PCCP》2011,13(7):2563-2570
The confined space synthesis method has been applied to the preparation of sodium tantalate (NaTaO(3)); hydrothermal reaction of NaOH and Ta(2)O(5) was carried out in the pores of a three-dimensional mesoporous carbon, which was replicated by the colloidal array of silica nanospheres (SNSs) 20 nm in size. This approach led to the formation of a colloidal array of NaTaO(3) nanoparticles 20 nm in size with a surface area of 34 m(2) g(-1). The photocatalytic performance of the colloidal array of NaTaO(3) nanoparticles for overall water splitting under UV irradiation (λ > 200 nm) was evaluated after loading a NiO cocatalyst onto NaTaO(3) samples. The NiO-loaded NaTaO(3) nanoparticles showed photocatalytic activity for overall water splitting more than three times as high as non-structured bulk NaTaO(3) particles. 相似文献
183.
Astulla A Hirasawa Y Rahman A Kusumawati I Ekasari W Widyawaruyanti A Zaini NC Morita H 《Natural product communications》2011,6(3):323-326
Two new acyclic diterpenes, melidianolic acids A (1) and B (2), have been isolated from the bark of Aphanamixis grandifolia. Their structures were elucidated on the basis of spectroscopic and chemical methods. Melidianolic acids A (1) and B (2) showed antimalarial activity against Plasmodium falciparum 3D7 with IC50 of 6.1 and 7.3 microg/mL, respectively. 相似文献
184.
185.
186.
187.
In this study, a simple and sensitive method for the determination of arsenic in water samples was developed. The method is based on the formation of micro particles of Ethyl Violet and molybdoarsenate, which gives an apparently homogeneous blue color to the solution. The absorption of the excess dye gradually decreases due to its conversion to a colorless carbinol species under strongly acidic conditions. Consequently, the sufficiently low reagent blank enables the spectrophotometric determination of arsenic with the detection limit of 4 microg l(-1). The coefficient of variation for the spectrophotometry at 50 microg l(-1) was 3.5% (n = 5). Furthermore, it is possible to detect concentrations as low as 10 microg l(-1) of arsenic visually. Our method will be useful as a simple, rapid, and cost-effective field test of arsenic, requiring no complex apparatus or skilled laboratory support. 相似文献
188.
189.
190.
Kinetic equations for the one-particle distribution function of dilute gases and plasmas and evolution equations for the variance of their fluctuations are obtained from the BBGKY hierarchy equations by using Mori's scaling method in an extended form. 相似文献