全文获取类型
收费全文 | 172篇 |
免费 | 0篇 |
专业分类
林业 | 4篇 |
农学 | 18篇 |
基础科学 | 1篇 |
6篇 | |
综合类 | 6篇 |
农作物 | 1篇 |
水产渔业 | 21篇 |
畜牧兽医 | 100篇 |
植物保护 | 15篇 |
出版年
2022年 | 1篇 |
2019年 | 3篇 |
2018年 | 1篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 1篇 |
2012年 | 1篇 |
2011年 | 5篇 |
2010年 | 12篇 |
2009年 | 16篇 |
2008年 | 4篇 |
2007年 | 9篇 |
2006年 | 11篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 1篇 |
1999年 | 1篇 |
1998年 | 4篇 |
1997年 | 7篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 11篇 |
1991年 | 3篇 |
1990年 | 6篇 |
1989年 | 9篇 |
1988年 | 7篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1966年 | 1篇 |
1955年 | 1篇 |
1952年 | 1篇 |
排序方式: 共有172条查询结果,搜索用时 45 毫秒
171.
Reduction of Cr(VI) by soil humic acids 总被引:1,自引:0,他引:1
The rate of hexavalent chromium reduction by a soil humic acid (SHA) was investigated in aqueous solutions where concentrations of Cr(VI), H+, and SHA were independently varied. Rate experiments were done with a large excess of SHA over Cr(VI). Rates of reduction depend strongly on [H+], increasing with decreasing pH. Typical Cr(VI)-SHA reactions display a nonlinear reduction of Cr(VI) with time that cannot be modelled with simple first- or second-order rate equations. An empirical rate equation is developed for Cr(VI)-soil humic acid reactions over a range of experimental conditions. The model is in part based on a reactive continuum concept developed for soil fulvic acids. The rate equation describing Cr(VI) reduction by SHA is: R= -(k0+k[H+]1/2)[HCrO4?]1/2Xe?1, where k0 is (8·3 ± 1·2) × 10?12, s?1k is (2·04 ± 0·05) × 10?9 l1/2 mol?1/2 s?1, and Xe is the equivalent fraction of SHA oxidized. The rate equation adequately models Cr(VI) reduction in an experiment with [Cr(VI)]0 four times greater than the maximum concentration used in its derivation. Cr(VI) reduction at pH 3 by two other SHAs can also be modelled using the rate equation. The difference between the rate coefficients for the humic acid and the fulvic acid from the same soil was greater than the difference in the rate coefficients for humic acids from different soils. 相似文献
172.
TAKAYOSHI MIYABAYASHI BVS MS PETER F. LORD BVSC FRCVS Dipiomate ACVR RICHARD R. DUBIELZIG DVM Diplomate ACVP DAVID S. BILLER DVM Dipiomate ACVR PAUL A. MANLEY DVM MS Diplomate ACVS 《Veterinary surgery : VS》1992,21(3):189-194
Collagenase, a proteolytic enzyme, was injected intradiscally in nine clinically normal, middle-aged beagles. Calcium chloride diluent solution (control), 100 ABC units of collagenase, and 250 ABC units of collagenase, were injected in randomly selected intervertebral discs (T13-L1 to L5-L6). On day 11, the discs injected with collagenase were narrowed radiographically, but there was no significant change in myelograms. Grossly and histologically, there was dissolution of the intervertebral discs, mainly nucleus pulposus, and protrusion of nucleus material in the vertebral body through bony end-plates in discs injected with collagenase. Collagenase chemonucleolysis may be an alternative to spinal surgery for intervertebral disc protrusion in dogs. 相似文献