全文获取类型
收费全文 | 87篇 |
免费 | 3篇 |
国内免费 | 17篇 |
专业分类
化学 | 58篇 |
晶体学 | 5篇 |
力学 | 5篇 |
综合类 | 2篇 |
数学 | 10篇 |
物理学 | 27篇 |
出版年
2022年 | 4篇 |
2021年 | 1篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2013年 | 3篇 |
2012年 | 12篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2009年 | 7篇 |
2008年 | 2篇 |
2007年 | 4篇 |
2006年 | 5篇 |
2005年 | 5篇 |
2004年 | 6篇 |
2003年 | 3篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1989年 | 1篇 |
1988年 | 1篇 |
排序方式: 共有107条查询结果,搜索用时 15 毫秒
1.
玻色—爱因斯坦凝聚和兰姆位移 总被引:1,自引:0,他引:1
扼要地介绍了BEC研究的近况和研究方向,同时报道了我们在BEC的光散射和兰姆位移方面的研究工作 相似文献
2.
3.
4.
流动注射电位滴定研究:氟化物沉淀滴定测锂 总被引:4,自引:0,他引:4
设计制作了一种简便的梯度混合室,并考察了其性能,试验结果证实了此混合室的合理性和有效性.用此混合室建立了流动注射电位滴定测锂的新方法,载流为1×10~(-5)~1×10~(-4)mol·L~(-1)的F~乙醇-水(9 1)溶液,流速4.2ml·min~(-1),混合室体积400μl,进样体积120μl,分析速度60样·h~(-1),检出范围取决于载流中滴定剂的浓度,方法用于卤水中锂的测定,结果令人满意. 相似文献
5.
Brain asymmetry is a phenomenon well known for handedness and has been studied in motor cortices. However, few quantitative studies on asymmetrical cortical activity in motor areas have been conducted. In this study, we systematically investigated asymmetrical cortical activity in motor areas during sequential finger movement by quantitatively analyzing functional magnetic resonance imaging (fMRI) blood oxygenation level-dependent (BOLD) responses. The norm of BOLD signal percentage of change was introduced to quantitatively measure the BOLD signal intensity change difference between the left and right motor areas. The results of the data collected from six subjects show that the norm of BOLD signal percentage of change in the right motor area is higher than that in the left motor area for two-hand movement (P=.0059) and single-hand movement (P=.0279) with right-handedness. These results from fMRI show the asymmetry of motor areas and may suggest that the left hemisphere motor area comes into being as an adaptation system that needs few neuron cells only to finish any movement task for right-handedness. The activation intensity in the left motor area is reduced with normal right finger movement. The activation intensity in the right motor area is obviously higher than that in the left motor area. 相似文献
6.
Significance of Branching for Transfection: Synthesis of Highly Branched Degradable Functional Poly(dimethylaminoethyl methacrylate) by Vinyl Oligomer Combination 下载免费PDF全文
Tianyu Zhao Hong Zhang Dr. Ben Newland Ahmed Aied Dr. Dezhong Zhou Dr. Wenxin Wang 《Angewandte Chemie (International ed. in English)》2014,53(24):6095-6100
A series of degradable branched PDMAEMA copolymers were investigated with the linear PDMAEMA counterpart as gene‐delivery vectors. The branched PDMAEMA copolymers were synthesized by controlled radical cross‐linking copolymerization based on the “vinyl oligomer combination” approach. Efficient degradation properties were observed for all of the copolymers. The degree of branching was found to have a big impact on performance in transfection when tested on different cell types. The product with the highest degree of branching and highest degree of functionality had a superior transfection profile in terms of both transfection capability and the preservation of cell viability. These branched PDMAEMA copolymers show high potential for gene‐delivery applications through a combination of the simplicity of their synthesis, their low toxicity, and their high performance. 相似文献
7.
8.
Dezhong Zou J. J. Aklonis R. Salovey 《Journal of polymer science. Part A, Polymer chemistry》1992,30(11):2443-2449
Monodisperse polymethacrylonitrile beads of varied size and crosslink density are prepared by emulsion copolymerization of methacrylonitrile and allylmethacrylate in the absence of emulsifier. The particle size is very sensitive to polymerization temperature and initiator concentration. Because of a nitrile group effect, the maximum conversion varies with reaction conditions. The highest conversion obtained was 82%. © 1992 John Wiley & Sons, Inc. 相似文献
9.
Fabrication and performance of microencapsulated phase change materials with hybrid shell by in situ polymerization in Pickering emulsion 下载免费PDF全文
Microencapsulated phase change materials (MePCMs) using melamine–formaldehyde resin/SiO2 as shell were investigated in this paper. Organically modified SiO2 particles were employed to stabilize Pickering emulsion, and in situ polymerization of melamine and formaldehyde was carried out to form hybrid shell. The performances of resultant MePCMs with hybrid shell were investigated comparatively with the MePCMs with polymer shell. SiO2 particles raise the microencapsulation efficiency by improving the stability of emulsion and providing a precipitation site for melamine–formaldehyde resin. Also, the mechanical strength, thermal reliability, and anti‐osmosis performance of MePCMs were improved significantly by SiO2 particles in the shell. Our study shows that Pickering emulsion is a simple and robust template for MePCMs with polymer‐inorganic hybrid shell. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
10.
氢化物—石墨炉原位富集原子吸收光谱法测定痕量锑 总被引:3,自引:0,他引:3
本文对标示问题进行了研究,自行设计了氢化物发生器,采用以石墨炉两端输入氢化物方式,载气流向用活塞控制,大幅度减少原子化阶段石墨炉内氢气分压,提高了锑的灵敏度,对氢化锑的石墨炉表面分解沉积和原子化机理进行了讨论,方法有于矿泉水和自来水痕量锑的测定,结果令人满意,锑的特征浓度为30pg/0.0044A。 相似文献