全文获取类型
收费全文 | 125篇 |
免费 | 6篇 |
国内免费 | 1篇 |
专业分类
化学 | 72篇 |
力学 | 3篇 |
数学 | 10篇 |
物理学 | 31篇 |
无线电 | 16篇 |
出版年
2021年 | 1篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 1篇 |
2013年 | 5篇 |
2012年 | 9篇 |
2011年 | 6篇 |
2010年 | 8篇 |
2009年 | 2篇 |
2008年 | 8篇 |
2007年 | 10篇 |
2006年 | 9篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 4篇 |
2002年 | 7篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1973年 | 2篇 |
1971年 | 1篇 |
1970年 | 3篇 |
1968年 | 1篇 |
排序方式: 共有132条查询结果,搜索用时 522 毫秒
51.
Tsung-Shan Tsou 《Computational Statistics》2016,31(3):845-857
A parametric robust approach for analyzing correlated count data is introduced. This method enables one to construct an asymptotically valid likelihood for the regression parameter when knowledge about the joint distribution for data is scarce or not available. We use simulations and real data analysis to demonstrate the merit of the proposed robust likelihood method. 相似文献
52.
This paper proposes a dynamic model for a defective production system with Poka-Yoke. Poka-Yoke is a Japanese phrase which means mistake-proofing. The technique of Poka-Yoke has been diversely applied in modern production systems. In this study, we evaluate the total cost of a defective production system with Poka-Yoke. We also use a practical case in automotive industry to verify the proposed model. The case study reveals that Poka-Yoke is a cost-effective mechanism that generates satisfactory return of a defective production system, the effect of which depends on the investment cost of Poka-Yoke. 相似文献
53.
Jared A. Butcher Hellmuth R. Hinz Nien-hua Tsou Swati Shah 《Tetrahedron letters》1984,25(48):5483-5486
A comparison of products formed during photolysis of 1,12-bis-[4-(2-oxo-3-phenylpropyl)phenyl]dodecane (1) reveals a difference in laser and lamp photolysis in that the use of a laser increases the yield of macrocyclic paracyclophane rings (2) by a factor of three. 相似文献
54.
The phenomenon of Coulomb enhancement, resulting from the consideration of many-body effects, is included in a detailed calculation of the gain of a quantum-well (QW) laser, which is then used to predict the laser's modulation response. Carrier transport in the separate-confinement heterostructure is taken into account. The modulation response is compared to experimental data and to predictions from calculations using only the free-carrier gain. The comparison shows that the inclusion of Coulomb enhancement in the theoretical calculations leads to better agreement between simulated and experimental data 相似文献
55.
56.
S. C. Tsou P. H. Tsien M. Takai D. Röschenthaler M. Ramin H. Ryssel I. Ruge 《Applied Physics A: Materials Science & Processing》1980,23(2):163-168
The annealing behavior of arsenic-implanted silicon under scanned cw CO2-laser irradiation from front and back surfaces is investigated. Ellipsometry, Hall effect, Rutherford backscattering measurements
and neutron activation analysis indicate an enhancement of annealing efficiency by laser irradiation from the back surface,
which provides complete recovery of crystal damage, high substitutionality and electrical activation of implanted arsenic
atoms without redistribution of concentration profile. The enhancement of annealing efficiency under back-surface irradiation
is explained by the difference in laser reflection from the front and back surface of silicon wafers. No differences in the
results are found for scanned and static annealing. 相似文献
57.
The reactions of chiral benzyl carbocations bearing alpha-phenyl substituents with N-sulfonylated indoles afford 1,1,2-triarylalkanes with anti-selectivities. This outcome is a reversal of facial diastereoselectivity relative to Bach's alpha-alkyl-bearing benzyl cations. The reactions are promoted by either a Br?nsted acid (TFA) or Lewis acid (BF3.OEt2), offering differential diastereoselectivities and reactivities. The electronic properties of both reacting partners strongly influence the reaction rates and the product diastereoselectivities and appear to operate under kinetic control. This chemistry provides an efficient access to sterically congested tetrasubstituted ethanes. 相似文献
58.
ABSTRACTWe demonstrate an image system with an optical image stabilisation using a droplet manipulation on a liquid crystal (LC) and polymer composite film (LCPCF) to reduce motion blur while preserve image quality. Such an image system adopts a liquid lens on an LCPCF and the mechanism is on a basis of droplet movement on LCPCF whose position changes because electrically tunable orientations of LC molecules on the surface of LCPCF. The change of position of the liquid lens compensates the deviation of light as the image system is under a handshake vibration. As a result, the image system under handshake vibrations could keep a clear image. The operating principles are introduced, and the experiments are performed and discussed. The concept in this paper can also be extended to design other optical components for modulating direction of light. 相似文献
59.
60.
Density functional theory has been used to investigate the properties of organic high spin molecules. The M05/cc-pVDZ calculations predict a septet ground state for the 2,3,6,7,10,11-hexahydro-1,4,5,8,9,12-hexaoxocoronene-2,3,6,7,10,11-hexayl radical (coronene-6O). The computations show further that the formation of intermolecular carbon-carbon bonds yields a singlet ground state for the dimer rather than a possible tridectet state as expected from the monomer's multiplicity. A benzene molecule placed between coronene-6O molecules leads to the desired high-spin cluster, but the overall stability of the cluster is low. A chromium atom inserted between two peripheral C(6) rings of coronene-6O yields a sandwich structure with the expected tridectet ground state and a binding energy which is 15 times larger than the corresponding tridectet dimer stabilized by a benzene molecule. The presented DFT calculations suggest that a chromium atom can effectively link organic polyradicals to larger magnetic units. 相似文献