全文获取类型
收费全文 | 684篇 |
免费 | 29篇 |
国内免费 | 3篇 |
专业分类
化学 | 501篇 |
力学 | 25篇 |
数学 | 99篇 |
物理学 | 91篇 |
出版年
2022年 | 6篇 |
2021年 | 7篇 |
2020年 | 6篇 |
2019年 | 12篇 |
2018年 | 10篇 |
2017年 | 7篇 |
2016年 | 10篇 |
2015年 | 14篇 |
2014年 | 28篇 |
2013年 | 30篇 |
2012年 | 46篇 |
2011年 | 67篇 |
2010年 | 31篇 |
2009年 | 34篇 |
2008年 | 50篇 |
2007年 | 44篇 |
2006年 | 45篇 |
2005年 | 42篇 |
2004年 | 39篇 |
2003年 | 18篇 |
2002年 | 27篇 |
2001年 | 10篇 |
2000年 | 4篇 |
1999年 | 8篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 12篇 |
1985年 | 17篇 |
1984年 | 10篇 |
1983年 | 2篇 |
1982年 | 8篇 |
1981年 | 7篇 |
1980年 | 5篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1936年 | 1篇 |
排序方式: 共有716条查询结果,搜索用时 15 毫秒
71.
Hussein El-Kashef Pascal Rathelot Patrice Vanelle Sylvain Rault 《Monatshefte für Chemie / Chemical Monthly》2007,138(5):469-476
Summary. 2-Amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile was converted into the corresponding 2-(pyrrol-1-yl) derivative, followed by reduction of the latter
compound into the corresponding amine. This amine and its acyl, aroyl, and arylidene derivatives were used as synthons in
the synthesis of several title compounds. 相似文献
72.
73.
Multinuclear NMR spectroscopy, relaxation and diffusion measurements were used recently to extract dynamical information on the long-time mobility of the water molecules and the neutralizing counterions condensed within the electrostatic well in the vicinity of the basal surface of clay particles. Multi-scale numerical modeling was used to interpret the NMR relaxation measurements and illustrate the interdependency between the solvent and ionic mobility and the organization of the anisotropic clay particles within the colloidal dispersions. 相似文献
74.
Based on the studies of influence of YAG laser heating conditions for Al alloy melt and steel on wettability,the mechanics of the laser overlap braze welding of 6056 Al and XC18 steel sheet has been investigated.Under the temperature range which is above the melting point of the Al alloy and below the melting point of the steel, two dissimilar metals can be joined by means of laser braze welding. There is no crack observed in the joining area, i.e. Al-Fe intermetallic phase (Fe3Al/FeAl/FeAl3/Fe2Al5) layer formed by solution and diffusion between liquid-solid interface. The temperature range can be defined as the process temperatures of laser braze welding of Al-Fe materials. Selecting a higher laser heating temperature can improve the wettability of Al melt to steel surface, but the intermetallic phase layer is also thicker. When the laser heating temperature is so high that the joining surface of steel is melted, there is a crack trend in the joining area. 相似文献
75.
76.
This paper develops a theoretical analysis of a Bingham fluid in slipping squeeze flow. The flow field decomposition consists
in combining a central extensional flow zone in the plane of symmetry and shear flow zones near the plates. It is also considered
that the slipping zone is located around a central sticking zone as previously shown from experiments. It is assumed that
the shear stress at the plates is constant in the slipping zone and equals a fixed friction yield value. The squeeze force
required to compress a Bingham fluid under the slipping behaviour as well as the radial evolution of the transition point
between both sticking and slipping zones are finally determined. 相似文献
77.
78.
Capillary electrophoresis for rapid identification of monoclonal antibodies for routine application in hospital
下载免费PDF全文
![点击此处可从《Electrophoresis》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Emmanuel Jaccoulet Claire Smadja Patrice Prognon Myriam Taverna 《Electrophoresis》2015,36(17):2050-2056
mAbs are widely used in cancer therapy. Their compounding, performed just before their administration to patients, is executed in a production unit of the hospital. Identification of these drugs, individually prepared in bags for infusion before patient administration, is of paramount importance to detect potential mistakes during compounding stage. A fast and reliable analytical method based on CZE combined to a cationic capillary coating (hexadimethrine bromide) was developed for identification of the most widely used compounded therapeutic for cancer therapy (bevacizumab, cetuximab, rituximab, and trastuzumab). Considering the high structural and physico‐chemical similarities of these mAbs, an extensive optimization of the BGE composition has been performed. The addition of perchlorate ions and polysorbate in the BGE greatly increased the resolution. To validate the method, an internal standard was used and the relative migration times (RTm) were estimated. Very satisfactory RSDs of the RTm for rituximab (0.76%), cetuximab (0.46%), bevacizumab (0.31%), and trastuzumab (0.60%) were obtained. The intraday and interday RSD of the method were less than 0.32 and 1.3%, respectively for RTm. Significant differences between theses RTms have been demonstrated allowing mAbs identification. Finally, accurate mAbs identification has been demonstrated by a blind test. 相似文献
79.
In squeeze flow rheometry, the main problem is the boundary condition between the squeezed material and the plates. Therefore, the crucial assumption is to know the location and the shape of the sample part where wall slip may or may not occur. This question is investigated from experimental results. For this, squeeze flow experiments are carried out to visualize the flow pattern at the walls. Influence of boundary conditions is particularly studied using different plate surface condition. As a result, with wall slipping conditions, we propose a flow modelling divided into two zones: a circular central zone of the sample sticks on the plates and, beyond that zone, the sample slips at the plates with friction. 相似文献
80.
James D. Oliver Adam A. Rosser Christopher M. Fellows Yohann Guillaneuf Jean-Louis Clement Marianne Gaborieau Patrice Castignolles 《Analytica chimica acta》2014
Direct UV detection of carbohydrates in free solution capillary electrophoresis at 270 nm is made possible by a photo-oxidation reaction. Glucose, rhamnose and xylose were shown to have unique UV absorption spectra hypothesizing different UV absorbing intermediates for their respective photo-oxidation. NMR spectroscopy of the photo-oxidation end products proved they consisted of carboxylates and not malondialdehyde as previously theorized and that oxygen thus plays a key role in the photo-oxidation pathway. Adding the photo-initiator Irgacure® 2959 in the background electrolyte increased sensitivity by 40% at an optimum concentration of 1 × 10−4 mM and 1 × 10−8 mM for conventional 50 μm i.d. capillaries and for the corresponding extended light path capillaries, respectively. 相似文献