全文获取类型
收费全文 | 120篇 |
免费 | 3篇 |
国内免费 | 1篇 |
专业分类
化学 | 78篇 |
晶体学 | 2篇 |
力学 | 1篇 |
数学 | 36篇 |
物理学 | 7篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2014年 | 2篇 |
2013年 | 4篇 |
2012年 | 8篇 |
2011年 | 6篇 |
2010年 | 6篇 |
2009年 | 3篇 |
2008年 | 10篇 |
2007年 | 4篇 |
2006年 | 7篇 |
2005年 | 4篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2002年 | 7篇 |
2000年 | 2篇 |
1997年 | 4篇 |
1995年 | 1篇 |
1994年 | 6篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1976年 | 1篇 |
1973年 | 1篇 |
1972年 | 3篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1967年 | 2篇 |
排序方式: 共有124条查询结果,搜索用时 156 毫秒
51.
Schmidt S Madaboosi N Uhlig K Köhler D Skirtach A Duschl C Möhwald H Volodkin DV 《Langmuir : the ACS journal of surfaces and colloids》2012,28(18):7249-7257
Chemical cross-linking is the standard approach to tune the mechanical properties of polymer coatings for cell culture applications. Here we show that the elastic modulus of highly swollen polyelectrolyte films composed of poly(L-lysine) (PLL) and hyaluronic acid (HA) can be changed by more than 1 order of magnitude by addition of gold nanoparticles (AuNPs) in a one-step procedure. This hydrogel-nanoparticle architecture has great potential as a platform for advanced cell engineering application, for example remote release of drugs. As a first step toward utilization of such films for biomedical applications we identify the most favorable polymer/nanoparticle composition for optimized cell adhesion on the films. Using atomic force microscopy (AFM) we determine the following surface parameters that are relevant for cell adhesion, i.e., stiffness, roughness, and protein interactions. Optimized cell adhesion is observed for films with an elastic modulus of about 1 MPa and a surface roughness on the order of 30 nm. The analysis further shows that AuNPs are not incorporated in the HA/PLL bulk but form clusters on the film surface. Combined studies of the elastic modulus and surface topography indicate a cluster percolation threshold at a critical surface coverage above which the film stiffness drastically increases. In this context we also discuss changes in film thickness, material density and swelling ratio due to nanoparticle treatment. 相似文献
52.
Dr. Dorothee Wasserberg Dr. Christian Haase Dr. Hoang D. Nguyen Jan Hendrik Schenkel Prof. Dr. Jurriaan Huskens Prof. Dr. Bart Jan Ravoo Dr. Pascal Jonkheijm Prof. Dr. Luc Brunsveld 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(22):6788-6794
Supramolecular assembly of proteins on surfaces and vesicles was investigated by site‐selective incorporation of a supramolecular guest element on proteins. Fluorescent proteins were site‐selectively labeled with bisadamantane by SNAP‐tag technology. The assembly of the bisadamantane functionalized SNAP‐fusion proteins on cyclodextrin‐coated surfaces yielded stable monolayers. The binding of the fusion proteins is specific and occurs with an affinity in the order of 106 M ?1 as determined by surface plasmon resonance. Reversible micropatterns of the fusion proteins on micropatterned cyclodextrin surfaces were visualized by using fluorescence microscopy. Furthermore, the guest‐functionalized proteins could be assembled out of solution specifically onto the surface of cyclodextrin vesicles. The SNAP‐tag labeling of proteins thus allows for assembly of modified proteins through a host–guest interaction on different surfaces. This provides a new strategy in fabricating protein patterns on surfaces and takes advantage of the high labeling efficiency of the SNAP‐tag with designed supramolecular elements. 相似文献
53.
54.
Dorothee Felix J. Schreiber K. Piers U. Horn A. Eschenmoser 《Helvetica chimica acta》1968,51(6):1461-1465
A new version of the epoxyketone → alkynone fragmentation is described. Hydrazones derived from cyclic α,β-epoxy-ketones and N-amino-aziridines decompose thermally into molecular nitrogen, an olefinic fragment and an acetylenic carbonyl compound (compare scheme 1). The reaction of phenylglyoxal with N-amino-phenyl-aziridine at room temperature produces styrene and diazo-acetophenone in high yield (compare scheme 3). 相似文献
55.
The high temperature superconductor YBa2Cu3O7–x has been studied by quantitative electron probe microanalysis (EPMA). After investigation of appropriate standards and choice between three different matrix correction methods this technique provides very accurate analytical results including those for oxygen. The quantitative results even allow the determination of the stoichiometry with deviations less than 2% relative. The application of computercontrolled EPMA is demonstrated by the characterization of the microstructure of a ceramic Y-Ba-Cu-O sample. Finally the properties of copperL
2 andL
3 valence band spectra are presented for compounds with copper in different valence state.Dedicated to Professor Günther Tölg on the occasion of his 60th birthday 相似文献
56.
By an on-column sol-gel process, a chiral monolithic stationary phase was prepared by the fusion of permethyl-beta-cyclodextrin-silica (Chira-Dex-silica) particles and by linking them to the internal capillary wall. The resulting monolith is stable toward voltage (30 kV) and pressure (300 bar) and possesses a high efficiency (up to 100,000 theoretical plates per meter). Efficient enantiomeric separation of various chiral compounds by pressure-supported capillary electrochromatography (CEC) was achieved. When comparing this method to capillary liquid chromatography (LC) employing the same column in an unified equipment, CEC shows a twofold higher column efficiency at comparable elution times and hence better resolution factors. 相似文献
57.
We establish an equidistribution theorem for the zeros of random holomorphic sections of high powers of a positive holomorphic line bundle. The equidistribution is associated with a family of singular moderate measures. We also give a convergence speed for the equidistribution. 相似文献
58.
59.
Dorothee Feldmüller 《manuscripta mathematica》1989,65(4):385-393
For a holomorphic action of a reductive complex Lie groupG on a Stein complex spaceX the map onto the categorical quotientX//G induces a mapPic(X//G)Pic(X) between the groups of holomorphic line bundles. Sufficient conditions are given for the injectivity of this map. The results are gained from a consideration of the relations between the cohomology rings (with values in ) ofX andX//G via Leray spectral sequence. 相似文献
60.
Buchheim Christoph Henke Dorothee Irmai Jannik 《Journal of Optimization Theory and Applications》2022,194(2):521-542
Journal of Optimization Theory and Applications - We consider a bilevel continuous knapsack problem where the leader controls the capacity of the knapsack, while the follower chooses a feasible... 相似文献