全文获取类型
收费全文 | 97篇 |
免费 | 6篇 |
国内免费 | 8篇 |
学科分类
数理化 | 111篇 |
出版年
2021年 | 3篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2017年 | 2篇 |
2014年 | 4篇 |
2013年 | 5篇 |
2012年 | 3篇 |
2011年 | 5篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 4篇 |
2007年 | 2篇 |
2006年 | 9篇 |
2005年 | 2篇 |
2004年 | 3篇 |
2003年 | 7篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1996年 | 8篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有111条查询结果,搜索用时 437 毫秒
1.
2.
3.
4.
本文建立了流动注射二甲酚橙光度法测定镀锌纯化液中Zn ̄2+的自动分析方法。利用区域采样技术和调整管路参数自动完成对样品的上千倍稀释,确定了最佳分析条件并研究了干扰离子的影响及消除办法。所建方法仪器简单,分析速度为84次/小时,变异系数(Zn ̄2+16.0g/L,n=20)为1.O%,用于实际钝化液分析,相对误差小于±10%。 相似文献
5.
DETECTION OF DNA-PSORALEN PHOTOADDUCTS in situ 总被引:1,自引:0,他引:1
ZOFIA ZAREBSKA† MARIA JARZABEK-CHORZELSKA ‡ GENOWEFA RZSA WIESLAW GLISKI MARIA PAWIKA TADEUSZ CHORZELSKI STEFANIA JABLOKA 《Photochemistry and photobiology》1984,39(3):307-312
Abstract— An immunological method, with the use of specific immune serum, has been developed for detection of 8-methoxypsoralen (8-MOP) photoadducts to DNA, formed in situ in cell nuclei, after combined treatment with 8MOP and UV-A irradiation (Zarçbska et al. , 1978). Lymphocytes fixed on slides or in suspension, and cryostat sections of different mammalian tissues, served as antigenic substrate, after treatment with 8-MOP and UV-A in vitro. Specific fluorescence in these substrates was detected in the nuclei after treatment with 30 ˜ 140 kJ/m2 UV-A in the presence of 0.1-0.3 μg/cm2 8-MOP. PHA-stimulated-lymphocytes appeared to be the most sensitive substrate.
However, hairless mice treated with high doses of UV-A in vivo , 70 ˜ 360 kJ/m2 did not reveal a specific fluorescence of epidermal nuclei, unless a high local concentration of 8-MOP was attained.
The apparent discrepancy in the level of photoadduct detection between the in vitro and in vivo treated specimens was explained by the low number of DNA-8-MOP-photoadducts formed in vivo under these experimental conditions. The relevance of these findings to the role of DNA-8-MOP-photoadducts formed during PUVA photochemotherapy is discussed. 相似文献
However, hairless mice treated with high doses of UV-A in vivo , 70 ˜ 360 kJ/m
The apparent discrepancy in the level of photoadduct detection between the in vitro and in vivo treated specimens was explained by the low number of DNA-8-MOP-photoadducts formed in vivo under these experimental conditions. The relevance of these findings to the role of DNA-8-MOP-photoadducts formed during PUVA photochemotherapy is discussed. 相似文献
6.
7.
8.
Jie Hu Haoshan Hao Changping Chen Delin Yang Xing Hu 《Journal of membrane science》2006,280(1-2):809-814
The oxygen permeation properties of mixed-conducting ceramics SrFeCo0.5O3−δ (SFCO), Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCFO), La0.2Sr0.8Co0.8Fe0.2O3−δ (LSCFO) and Ba0.95Ca0.05Co0.8Fe0.2O3−δ (BCCFO) were studied by thermogravimetric method in the temperature range 600–900 °C. The results show that the oxygen adsorption rate constants ka of all material are larger than oxygen desorption rate constants kd and both ka and kd are not strongly dependent on temperature in the studied temperature range. The oxygen vacancy contents δ(N2) and δ(O2) in nitrogen and oxygen and their difference Δδ = δ(N2) − δ(O2) play an important role in determining the temperature behavior of oxygen permeation flux JO2. 相似文献
9.
Improvement of the weighted essentially nonoscillatory scheme based on the interaction of smoothness indicators 下载免费PDF全文
The weighted essentially nonoscillatory scheme is improved by introducing new smoothness indicators that evaluate the interactions among the classical smoothness indicators suggested by Jiang and Shu. The effect of the key parameters in the new smoothness indicators on the scheme is systematically investigated. The improved scheme has smaller dissipation with larger weight assignment to the discontinuous stencils and higher numerical accuracy with weights closer to the ideal weights. To verify the theory, benchmark problems governed by the linear transport equation, the 1‐dimensional nonlinear Burgers equation, and the Euler equations are conducted and analyzed, respectively. Better computational performances both on numerical resolution and accuracy are shown in the comparisons with other classical weighted essentially nonoscillatory schemes. 相似文献
10.
A numerical solution for the simultaneous disturbance decoupling and row-by-row decoupling problem 总被引:1,自引:0,他引:1
The numerical computation of the simultaneous disturbance decoupling and row-by-row decoupling problem is considered. Based on a condensed form for the system matrices the solvability of the simultaneous disturbance decoupling and row-by-row decoupling problem is reduced to the verification of an integer equality and the nonsingularity of a lower-dimensional constant matrix. The condensed form we use is computed using only orthogonal transformations, which can be implemented in a numerically stable way. Hence, it leads directly to an effective numerical method for solving the disturbance decoupling and row-by-row decoupling problem using existing tools such as LAPACK and Matlab. Our result complements existing geometric and structural approaches which are of a theoretical nature and are not suitable for numerical computation. 相似文献