全文获取类型
收费全文 | 612篇 |
免费 | 15篇 |
国内免费 | 1篇 |
专业分类
化学 | 451篇 |
晶体学 | 15篇 |
力学 | 13篇 |
数学 | 19篇 |
物理学 | 130篇 |
出版年
2023年 | 4篇 |
2021年 | 7篇 |
2020年 | 7篇 |
2019年 | 17篇 |
2018年 | 10篇 |
2017年 | 11篇 |
2016年 | 8篇 |
2015年 | 6篇 |
2014年 | 15篇 |
2013年 | 20篇 |
2012年 | 24篇 |
2011年 | 24篇 |
2010年 | 17篇 |
2009年 | 20篇 |
2008年 | 35篇 |
2007年 | 31篇 |
2006年 | 35篇 |
2005年 | 36篇 |
2004年 | 38篇 |
2003年 | 26篇 |
2002年 | 26篇 |
2001年 | 9篇 |
2000年 | 19篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 10篇 |
1996年 | 12篇 |
1995年 | 7篇 |
1994年 | 10篇 |
1993年 | 10篇 |
1992年 | 11篇 |
1991年 | 8篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1985年 | 12篇 |
1984年 | 11篇 |
1983年 | 6篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1974年 | 3篇 |
1972年 | 2篇 |
1970年 | 2篇 |
1941年 | 2篇 |
1936年 | 2篇 |
排序方式: 共有628条查询结果,搜索用时 15 毫秒
51.
Sakagami M Horie K Nakamoto K Kawaguchi T Hamana H 《Chemical & pharmaceutical bulletin》2000,48(9):1256-1263
Sialyl Lewis X (SLeX) is well known as a ligand of the cell adhesion molecule E-selectin which is specifically expressed at inflammatory lesion sites. We have synthesized several SLeX-polysaccharide conjugates and examined their potential for drug delivery to inflammatory lesions. The AUC (area under the blood concentration-time curve) 0-24 h of SLeX-CMCht (1), SLeX-CMPul (2) and SLeX-DSH (3) at the inflammatory lesion was about 60-, 300-, and 30-fold higher than that of the monovalent SLeX (7), respectively. Moreover, 1 showed 2-fold higher accumulation in the inflammatory lesion than SLN-CMCht (4), and 2 showed 2.5-fold higher accumulation than SLN-CMPul (5). 相似文献
52.
53.
T. Sato A. Narazaki Y. Kawaguchi H. Niino 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1477-1479
Laser irradiation of solid nitrogen containing cyanuric triazide (C3N12) could generate highly reactive carbon nitride species, NCN and dicyanocarbodiimide. These species were generated in the solid nitrogen at 20 K. After laser photolysis, generated reactive species were concentrated by removal of nitrogen, and converted into a film-like product. Thus, the obtained product was characterized by means of FTIR, SEM, and XPS measurements. The product was assigned to amorphous carbon nitride with relatively high nitrogen content (N/C=0.91.3). PACS 81.15.Fg; 82.33.-z; 68.55.Nq 相似文献
54.
Itaka K Kanayama N Nishiyama N Jang WD Yamasaki Y Nakamura K Kawaguchi H Kataoka K 《Journal of the American Chemical Society》2004,126(42):13612-13613
An siRNA nanocarrier formed through self-assembly of PEG-based block catiomer possessing two distinct amino groups with different pKa values in a side chain was developed. This design provided the carrier with a sufficient siRNA complexation and an assumed buffering capacity in the endosomes, allowing it to exhibit remarkable gene knockdown abilities as well as sufficient serum tolerability. 相似文献
55.
Eguchi K Enomoto S Furuno K Goldman J Hanada H Ikeda H Ikeda K Inoue K Ishihara K Itoh W Iwamoto T Kawaguchi T Kawashima T Kinoshita H Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Nakajima M Nakajima T Ogawa H Owada K Sakabe T Shimizu I Shirai J Suekane F Suzuki A Tada K Tajima O Takayama T Tamae K Watanabe H Busenitz J Djurcic Z McKinny K Mei DM Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fu Y Fujikawa BK Heeger KM Lesko KT Luk KB Murayama H 《Physical review letters》2003,90(2):021802
KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded. 相似文献
56.
57.
Silicon clathrate with an f-electron system 总被引:1,自引:0,他引:1
A novel crystal of Ba6Ce2Au4Si42 with Ba and Ce encapsulated into silicon-polyhedral clusters is self-assembled from the state of elemental mixture. Each atom in the crystal is arranged in its well-defined position with a nanoscale period, causing unique interactions between the conduction and the magnetic electrons originating from the independent sources of Ba and Ce, respectively. In this system, the long-distant magnetic f electrons can interact with each other through nanoscale spacing with isotropic three dimensionality, leading to the occurrence of a unique spontaneous spin ordering at 6.5 K. 相似文献
58.
59.
Tetsuya Yuasa Shinji Tanosaki Yoshiaki Sasaki Michiaki Takagi Akira Ishikawa Hiroshi Taniguchi Balasigamani Devaraj Takao Akatsuka 《Analytical sciences》2002,18(12):1329-1333
The coherent detection imaging (CDI) method uses the optical heterodyne detection technique. CW and single frequency lasers having long coherence lengths are used to exploit the maximum advantages of heterodyne detection, such as high directionality, selectivity and sensitivity. The CDI method based on optical heterodyne detection enables selective filtering of the directional coherence-retaining emergent photons, which leads to image reconstruction from projections, similar to X-ray computed tomography (CT). So far we have demonstrated the advantages and capabilities of the measurement technique for transillumination optical computed tomography in biomedicine. Here, we investigate the fundamental imaging properties of CDI method, such as its high directionality and quantitativeness, with preliminary physical phantom experiments. The results show that the CDI method satisfies the requirements for CT reconstruction under the first order approximation, and enables quantitative measurements in the sense that the relationship between estimated and actual concentration retains a satisfactory linearity. 相似文献
60.