全文获取类型
收费全文 | 128篇 |
免费 | 3篇 |
专业分类
化学 | 69篇 |
力学 | 3篇 |
数学 | 2篇 |
物理学 | 57篇 |
出版年
2022年 | 1篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2013年 | 7篇 |
2012年 | 4篇 |
2011年 | 11篇 |
2010年 | 6篇 |
2009年 | 1篇 |
2008年 | 4篇 |
2007年 | 3篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 6篇 |
2003年 | 1篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1995年 | 1篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 1篇 |
1990年 | 5篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1981年 | 8篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 2篇 |
排序方式: 共有131条查询结果,搜索用时 15 毫秒
41.
The problem of the oscillatory free induction decay in the angular distribution of nuclear radiations is theoretically examined for inhomogeneous linewidths, with and without the influence of the skin effect, utilizing the method of concatenation of perturbation factors. The second rank detection tensor applicable to gamma detected pulsed NMRON signals from ferromagnetic metals is examined for axial geometry. Important extensions to the pulse area theorem originally developed only for the first rank detection tensor are proposed for second rank tensors. 相似文献
42.
J. B. Nickaf R. P. Burford R. P. Chaplin 《Journal of polymer science. Part A, Polymer chemistry》1995,33(7):1125-1132
The homopolymerization of 1,3-butadiene in a stirred batch reactor with the catalytic system Nd octoate/diethyl-aluminium chloride/triisobutyl-aluminium in n-heptane was studied. The effect of various reaction conditions on especially high conversion and molecular weight is reported. Polymerization is shown to be first order with respect to both monomer and neodymium. Molecular weights are high and broadly distributed. Chain transfer to triisobutylaluminium is the main factor governing molecular weight development. A mechanism of polymerization is presented with the chain transfer process incorporated. © 1995 John Wiley & Sons, Inc. 相似文献
43.
Amine-borane sigma-complexes of rhodium. relevance to the catalytic dehydrogenation of amine-boranes
Rhodium amine-borane sigma-complexes of H3BNHMe2 have been isolated which are potential intermediates in the catalytic dehydrogenation of H3B.NHMe2. 相似文献
44.
Adrian B. Chaplin Zoltán Béni Christian G. Hartinger Hisham Ben Hamidane Andrew D. Phillips Rosario Scopelliti Paul J. Dyson 《Journal of Cluster Science》2008,19(1):295-309
The new mixed-metal complex {anti-[(p-cymene)RuCl]-μ-[κ
2-P,P′;κ
1-P′′-(PPh2CH2)3CMe]-[AuCl]}PF6 and its cluster derivative {anti-[(p-cymene)RuCl]-μ-[κ
2-P,P′;κ
1-P′′-(PPh2CH2)3CMe]-[AuPt3(CO)3(PCy3)3]}(PF6)2 have been prepared and characterized. Notably, NMR spectroscopy and high resolution FT-ICR mass spectrometry, including a
tandem mass spectrometric analysis, demonstrated the formation of these compounds that was also confirmed by single crystal
X-ray diffraction analysis. 相似文献
45.
Dallanegra R Pilgrim BS Chaplin AB Donohoe TJ Weller AS 《Dalton transactions (Cambridge, England : 2003)》2011,40(25):6626-6628
The metal-promoted dehydrogenation of cyclic thioethers S(C(5)H(9))(R) (R = C(5)H(9), Ph) to give the corresponding cycloalkenes, S(C(5)H(7))(R), using the [Rh{Ph(2)P(CH(2))(3)PPh(2)}](+) fragment is reported. 相似文献
46.
Oxazolidinones are powerful promoters of the Nazarov reaction, enabling the cyclization of conventionally resistant substrates to be achieved under mild conditions. They exert excellent regio- and torquoselective control in both the conventional Nazarov reaction giving cyclopentenones and in the "interrupted" Nazarov reaction, giving more highly substituted multistereocenter containing products. 相似文献
47.
Ridgway SH Elsberry WR Blackwood DJ Kamolnick T Todd M Carder DA Chaplin M Cranford TW 《The Journal of the Acoustical Society of America》2012,131(1):593-598
Bottlenose dolphins (Tursiops truncatus) wore opaque suction cups over their eyes while stationing behind an acoustically opaque door. This put the dolphins in a known position and orientation. When the door opened, the dolphin clicked to detect targets. Trainers specified that Dolphin S emit a whistle if the target was a 7.5 cm water filled sphere, or a pulse burst if the target was a rock. S remained quiet if there was no target. Dolphin B whistled for the sphere. She remained quiet for rock and for no target. Thus, S had to choose between three different responses, whistle, pulse burst, or remain quiet. B had to choose between two different responses, whistle or remain quiet. S gave correct vocal responses averaging 114 ms after her last echolocation click (range 182 ms before and 219 ms after the last click). Average response for B was 21 ms before her last echolocation click (range 250 ms before and 95 ms after the last click in the train). More often than not, B began her whistle response before her echolocation train ended. The findings suggest separate neural pathways for generation of response vocalizations as opposed to echolocation clicks. 相似文献
48.
E. V. Stepanova T. O. Chaplin Yu. D. Chashechkin 《Journal of Applied Mechanics and Technical Physics》2013,54(3):408-414
Experiments were performed to study oil transport in the compound vortex produced by a uniformly rotating disk in a cylindrical container. It was found that on the liquid surface in the neighborhood of the axis of rotation, light oil formed a spot with spiral branches or broke up into separate elongated drops, and the spiral branches stretched out in the direction opposite to the direction of rotation of the liquid. In the bulk of the liquid in the vicinity of the axis of its rotation, oil formed a compact body. The geometric parameters of the structural components of the flows were determined. 相似文献
49.
Jianbang Ge Xingli Zou Soroush Almassi Li Ji Brian P. Chaplin Allen J. Bard 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(45):16369-16374
The current Si production process is based on the high‐temperature (1700 °C) reduction of SiO2 with carbon that produces large amounts of CO2. We report an alternative low‐temperature (850 °C) process based on the reduction of SiO2 in molten CaCl2 that does not produce CO2. It utilizes an anode material (Ti4O7) capable of sustained oxygen evolution. Two types of this anode material, dense Ti4O7 and porous Ti4O7, were tested. The dense anode showed a better performance. The anode stability is attributed to the formation of a protective TiO2 layer on its surface. In situ periodic current reversal and ex situ H2 reduction could be used for extending the lifetime of the anodes. The findings show that this material can be applied as a recyclable anode in molten CaCl2. Si wires, films, and particles were deposited with this anode under different cathodic current densities. The prepared Si film exhibited ≈30–40 % of the photocurrent response of a commercial p‐type Si wafer, indicating potential use in photovoltaic cells. 相似文献
50.