全文获取类型
收费全文 | 730篇 |
免费 | 56篇 |
国内免费 | 4篇 |
专业分类
化学 | 592篇 |
晶体学 | 1篇 |
力学 | 24篇 |
数学 | 66篇 |
物理学 | 107篇 |
出版年
2024年 | 1篇 |
2023年 | 12篇 |
2022年 | 12篇 |
2021年 | 14篇 |
2020年 | 31篇 |
2019年 | 16篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 30篇 |
2015年 | 35篇 |
2014年 | 33篇 |
2013年 | 39篇 |
2012年 | 81篇 |
2011年 | 86篇 |
2010年 | 43篇 |
2009年 | 35篇 |
2008年 | 50篇 |
2007年 | 49篇 |
2006年 | 36篇 |
2005年 | 36篇 |
2004年 | 32篇 |
2003年 | 16篇 |
2002年 | 13篇 |
2001年 | 10篇 |
2000年 | 8篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 6篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1978年 | 1篇 |
1976年 | 2篇 |
1975年 | 3篇 |
1972年 | 1篇 |
1968年 | 3篇 |
1890年 | 2篇 |
排序方式: 共有790条查询结果,搜索用时 15 毫秒
61.
62.
Cyrielle Roquelet Jean‐Sébastien Lauret Dr. Valérie Alain‐Rizzo Dr. Christophe Voisin Dr. Romain Fleurier Dr. Morgan Delarue Damien Garrot Dr. Annick Loiseau Prof. Philippe Roussignol Prof. Jacques A. Delaire Prof. Emmanuelle Deleporte Prof. 《Chemphyschem》2010,11(8):1667-1672
We report on a new, original and efficient method for π‐stacking functionalization of single‐wall carbon nanotubes. This method is applied to the synthesis of a high‐yield light‐harvesting system combining single‐wall carbon nanotubes and porphyrin molecules. We developed a micelle‐swelling technique that leads to controlled and stable complexes presenting an efficient energy transfer. We demonstrate the key role of the organic solvent in the functionalization mechanism. By swelling the micelles, the solvent helps the non‐water‐soluble porphyrins to reach the micelle core and allows a strong enhancement of the interaction between porphyrins and nanotubes. This technique opens new avenues for the functionalization of carbon nanostructures. 相似文献
63.
Damien Montange Michel Bérard Martin Demarchi Patrice Muret Sarah Piédoux Jean Pierre Kantelip Bernard Royer 《Journal of mass spectrometry : JMS》2010,45(6):670-677
The anticancer drug capecitabine and its metabolites [including the active metabolite 5‐fluorouracil (5‐FU)] display high pharmacokinetic inter‐patient variability. Such variability, which may lead to treatment failure or toxicity, could need drug concentration measurement to individualize dosing regimen. However, usual assay methods are often long and fastidious. A simultaneous and cost‐effective method was thus developed for the determination of the concentrations of these compounds in human plasma. Compounds were extracted via a classic liquid–liquid extraction. Chromatographic analysis was performed on a C18 reverse phase column with detection by atmosphere pressure chemical ionization LC‐MS/MS. Our method allows a good chromatographic separation of the compounds and was fully validated following Food and Drug Administration (FDA) recommendations (good selectivity, no carry‐over, linearity of the calibration curves without weighting, deviations from nominal concentrations of standard samples lower than 15%, intra‐ and inter‐assay precision and accuracy lower than 15%). Recovery and stability were also acceptable following the FDA guidelines. A matrix effect impairing the determination of 5‐FU was avoided by using a stable isotopic derivative of 5‐FU as internal standard. Interestingly, this method allows detection of TetraHydroUridine, an inhibitor of ex vivo degradation of metabolites, which is essential for the stability, the adequate conditioning of blood samples and for good laboratory practice, essential in routine determination. This method seems usable to routinely determine concentrations of capecitabine and its metabolites in blood and may be helpful in further studies aiming at performing therapeutic drug monitoring. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
64.
Generating quantum entanglement is not only an important scientific endeavor, but will be essential to realizing quantum-enhanced technologies, in particular, quantum-enhanced measurements with precision beyond classical limits. We investigate the heralded generation of multiphoton entanglement for quantum metrology using a reconfigurable integrated waveguide device in which projective measurement of auxiliary photons heralds the generation of path-entangled states. We use four and six-photon inputs, to analyze the heralding process of two- and four-photon NOON states-a superposition of N photons in two paths, capable of enabling phase supersensitive measurements at the Heisenberg limit. Realistic devices will include imperfections; as part of the heralded state preparation, we demonstrate phase superresolution within our chip with a state that is more robust to photon loss. 相似文献
65.
We consider the counterpropagating interaction of a signal and a pump beam in a spun fiber and in a randomly birefringent fiber, the latter being relevant to optical telecommunication systems. On the basis of a geometrical analysis of the Hamiltonian singularities of the system, we provide a complete understanding of the phenomenon of polarization attraction in these two systems, which allows to achieve a control of the polarization state of the signal beam by adjusting the polarization of the pump. In spun fibers, all polarization states of the signal beam are attracted toward a specific line of polarization states on the Poincaré sphere, whose characteristics are determined by the polarization state of the injected backward pump. In randomly birefringent telecommunication fibers, we show that an unpolarized signal beam can be repolarized into any particular polarization state, without loss of energy. 相似文献
66.
We consider the dynamics of the domain-wall kink soliton, in particular we study the zero mode of translation. In the infinitely-thin kink limit, we show that the zero mode is almost completely frozen out, the only remnant being a dynamically constrained four-dimensional mode of a single but arbitrary frequency. In relation to this result, we show that the usual mode expansion for dealing with zero modes - implicit collective coordinates - is not in fact a completely general expansion, and that one must use instead a traditional generalised Fourier analysis. 相似文献
67.
68.
Damien Lamberton 《随机分析与应用》2013,31(3):603-623
Abstract In this article we investigate the rate of convergence of the so-called two-armed bandit algorithm. The behavior of the algorithm turns out to be highly non standard: no central limit theorem, possible occurrence of two different rates of convergence with positive probability. 相似文献
69.
70.
Damien Qumener Valrie Hroguez Yves Gnanou 《Journal of polymer science. Part A, Polymer chemistry》2005,43(1):217-229
This study describes the synthesis of polynorbornene colloidal particles able to release active molecules in response to pH change. Such functionalized polynorbornene latices with surface active molecules have been obtained by ring‐opening metathesis copolymerization in a dichloromethane/ethanol medium in the presence of α‐norbornenyl poly(ethylene oxide) macromonomer. Two different strategies of introduction of the active molecule—either at their periphery or at their core— have been contemplated. The particles have been characterized by both dynamic light scattering and transmission electron microscopy. Their size was found to range from 260 to 600 nm. The release of the active molecules was monitored by UV spectrometry. After 48 h in an appropriate HCl buffer (pH = 3) more than 80% of the initially linked active molecule was released. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 217–229, 2005 相似文献