全文获取类型
收费全文 | 308篇 |
免费 | 37篇 |
国内免费 | 4篇 |
专业分类
化学 | 237篇 |
晶体学 | 2篇 |
力学 | 7篇 |
综合类 | 6篇 |
数学 | 27篇 |
物理学 | 70篇 |
出版年
2023年 | 2篇 |
2021年 | 6篇 |
2020年 | 8篇 |
2019年 | 5篇 |
2018年 | 9篇 |
2017年 | 4篇 |
2016年 | 12篇 |
2015年 | 12篇 |
2014年 | 19篇 |
2013年 | 28篇 |
2012年 | 22篇 |
2011年 | 19篇 |
2010年 | 23篇 |
2009年 | 13篇 |
2008年 | 17篇 |
2007年 | 19篇 |
2006年 | 18篇 |
2005年 | 13篇 |
2004年 | 12篇 |
2003年 | 13篇 |
2002年 | 6篇 |
2001年 | 8篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 8篇 |
1994年 | 4篇 |
1993年 | 7篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 5篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有349条查询结果,搜索用时 15 毫秒
1.
2.
3.
Yang‐Chu Lin Kung‐Lung Cheng Woan‐Shiow Tzeng Chih‐Lin Su Long‐Je Lee Ling‐Yung Wang 《Liquid crystals》2013,40(3):289-293
A series of N,N‐disubstituted‐4‐[(4‐aminophenyl)diazenyl]benzylidene‐4′‐alkylanilines (azo dyes) were synthesized from the reaction of the corresponding benzaldehyde with alkylanilines. These azo dyes exhibit nematic and SmC phases on heating. Their order parameter, photo‐stability and miscibility were studied by investigation of a representative sample. 相似文献
4.
5.
Lipases and esterases are important catalysts with wide varieties of industrial applications. Although many methods have been established for detecting their activities, a simple and sensitive approach for picogram detection of lipolytic enzyme quantity is still highly desirable. Here we report a lipase detection assay which is 1000-fold more sensitive than previously reported methods. Our assay enables the detection of as low as 5 pg and 180 pg of lipolytic activity by direct spotting and zymography, respectively. Furthermore, we demonstrated that the detection sensitivity was adjustable by varying the buffering capacity, which allows for screening of both high and low abundance lipolytic enzymes. Coupled with liquid chromatography-mass spectrometry, our method provides a useful tool for sensitive detection and identification of lipolytic enzymes. 相似文献
6.
Tsai Chia-Wei Lin Jason Chiu Lung Yang Chun-Wei 《International Journal of Theoretical Physics》2021,60(9):3599-3608
International Journal of Theoretical Physics - Ma et al. [Int. J. Theor. Phys. (2021): 1328–1338] proposed a multi-party quantum key distribution (MQKD) protocol using Bell states, in which... 相似文献
7.
8.
Carmine Coluccini Yoke Mooi Ng Yves Ira A. Reyes Hsin-Yi Tiffany Chen Yit Lung Khung 《Molecules (Basel, Switzerland)》2020,25(22)
In this paper, a modified Cyclotriveratrylene was synthesized and linked to a branched Polyethylenimine, and this unique polymeric material was subsequently examined as a potential supramolecular carrier for Doxorubicin. Spectroscopic analysis in different solvents had shown that Doxorubicin was coordinated within the hollow-shaped unit of the armed Cyclotriveratrylene, and the nature of the host–guest complex revealed intrinsic Van der Waals interactions and hydrogen bonding between the host and guest. The strongest interaction was detected in water because of the hydrophobic effect shared between the aromatic groups of the Doxorubicin and Cyclotriveratrylene unit. Density functional theory calculations had also confirmed that in the most stable coordination of Doxorubicin with the cross-linked polymer, the aromatic rings of the Doxorubicin were localized toward the Cyclotriveratrylene core, while its aliphatic chains aligned closer with amino groups, thus forming a compact supramolecular assembly that may confer a shielding effect on Doxorubicin. These observations had emphasized the importance of supramolecular considerations when designing a novel drug delivery platform. 相似文献
9.
M. McCulloch S. K. Fadeff G. M. Mong R. G. Riley D. S. Sklarew B. L. Thomas 《International journal of environmental analytical chemistry》2013,93(2-4):289-293
Abstract DOE Methods for Evaluating Environmental and Waste Management Samples (DOE Methods) is a guidance/methods document to support sampling and analysis activities at DOE sites. DOE Methods is intended to supplement existing guidance documents (e.g., EPA's Test Methods for Evaluating Solid Waste, SW-846), which generally apply to low-level or nonradioactive samples. DOE Methods targets the complexities of DOE radioactive mixed waste and environmental samples. The document contains quality assurance (QA), quality control (QC), safety, sampling, organic analysis, inorganic analysis, and radioanalytical guidance as well as sampling and analytical methods. An addendum is distributed every six months (April and October) with updated guidance and additional methods. DOE Methods provides a vehicle for technology transfer within the environmental restoration (ER) and waste management (WM) (collectively known as EM) community. As DOE Methods evolves, its usefulness and applicability are anticipated to grow to meet the demands of the DOE/EM mission. At the present time, DOE Methods contains methods and guidance information supplied by DOE sites. Because the EM activities in DOE are not unique to the United States, the international environmental community could benefit from the information gathered for the DOE program. This information could provide additional resources for their EM activities. 相似文献
10.