全文获取类型
收费全文 | 103篇 |
免费 | 2篇 |
国内免费 | 3篇 |
专业分类
化学 | 50篇 |
力学 | 2篇 |
数学 | 24篇 |
物理学 | 32篇 |
出版年
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 1篇 |
2016年 | 4篇 |
2015年 | 1篇 |
2014年 | 5篇 |
2013年 | 4篇 |
2012年 | 5篇 |
2011年 | 9篇 |
2010年 | 5篇 |
2009年 | 4篇 |
2008年 | 5篇 |
2007年 | 7篇 |
2006年 | 3篇 |
2005年 | 7篇 |
2004年 | 4篇 |
2003年 | 6篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1980年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有108条查询结果,搜索用时 31 毫秒
81.
Summary Some Results of Investigations Into Relationship Between a Few Elements of Nodular Graphite Cast Iron and Nodular Graphite An investigation of the fractured surfaces of pins, having a diameter of 1.5 mm, obtained during the production of commercial nodular cast irons of Meehanite types is reported. The investigation was performed using a scanning electron microsopec (SEM) with an attachment for energy dispersive analysis and scanning Auger microprobe (SAM), where the principal attention was given to SAM. Point analysis, Auger images and Auger line scans were performed on the fractured surfaces and also approximately 200 Å and 1m below the surface. The nodule/metal and intercrystalline graphite interfaces in the investigated iron were free of foreign elements.The paper has been presented at 12th Colloquium on Materials Analysis, Institute for Analytical Chemistry, Technical University in Vienna, May 13–15, 1985. 相似文献
82.
AES sputter depth profiles of multilayers with constituents of very different backscattering factors show characteristic distortions in the shape of the intensity–depth profiles. These distortions are quantified by introducing an extension of the local effective backscattering factor concept developed in an earlier paper in the mixing‐roughness‐information depth (MRI) model for profile quantification. The extension is based on a linear superposition of two newly defined parameters, the effective backscattering factors for each interface that are diminished with distance from the respective interface by another characteristic parameter, the mean effective backscattering decay length. As shown for a Ni/C multilayer structure of six alternating layers of Ni (38 nm) and C (25 nm) on a Si substrate, AES intensity depth profiles calculated with the presented modification of the MRI model, yield an excellent agreement with the measured profile after some adjustment of the initial mean effective backscattering decay lengths and, sometimes, after a slight change of the backscattering factors given by the Ichimura–Shimizu relations. The backscattering effect is studied as a function of the single layer thickness. A critical layer thickness can be determined, below which the backscattering influence becomes negligible for typical AES depth profiling results. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
83.
Borut Bajc Saša Prelovšek Mitja Rosina 《Zeitschrift für Physik A Hadrons and Nuclei》1996,356(1):187-191
Theγγ →ρ 0 ρ 0 → 4π reaction shows a broad peak at 1.5 GeV in the (J P ,J z )=(2+,2) channel which has no counterpart in theρ + ρ ? channel. This “resonance” is considered as a candidate for a qq $\bar q$ ; $\bar q$ state in the “s-channel”. We show, however, that it can also be explained by potential scattering ofρ 0 ρ 0 via theσ- exchange in the “t-channel”. 相似文献
84.
Ľudmila Bezegová Borut Lužar Martina Mockovčiaková Roman Soták Riste Škrekovski 《Journal of Graph Theory》2016,81(1):73-82
A star edge coloring of a graph is a proper edge coloring without bichromatic paths and cycles of length four. In this article, we establish tight upper bounds for trees and subcubic outerplanar graphs, and derive an upper bound for outerplanar graphs. 相似文献
85.
86.
87.
Cordoyiannis G Lebar A Zalar B Zumer S Finkelmann H Kutnjak Z 《Physical review letters》2007,99(19):197801
A high-resolution calorimetry and deuteron-nuclear magnetic resonance study of a paranematic-nematic phase transition was performed on liquid single-crystal elastomers. We show that density variations of both rodlike and pointlike cross-links strongly affect the mean value and the dispersion of local mechanical fields. The system exhibits an inherent weakly disordered orientational state composed of regions with the temperature profile of the nematic order parameter ranging from first order to supercritical. On increasing the cross-linking density the predominantly first order thermodynamic response transforms into a predominantly supercritical one. 相似文献
88.
Accumulation of 226Ra, 238U and 230Th by wetland plants in a vicinity of U-mill tailings at Žirovski vrh (Slovenia) 总被引:1,自引:0,他引:1
Marko Černe Borut Smodiš Marko Štrok Radojko Jaćimović 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(2):323-327
The impact of a U-mill tailing on radionuclide accumulation by plants was assayed. In particular, a preliminary screening of 226Ra, 238U and 230Th in Marsh marigold (Caltha palustris L.), soft rush (Juncus effusus L.) and Tall Moor grass (Molinia arundinacea (L.) Moench) grown in a marsh habitat is presented. Activity concentrations for the studied radionuclides and their transfer factors for the particular plants are shown and discussed. 相似文献
89.
František Kardoš Matjaž Krnc Borut Lužar Riste Škrekovski 《Journal of mathematical chemistry》2010,47(2):771-789
A fullerene graph is a planar cubic graph whose all faces are pentagonal and hexagonal. The structure of cyclic edge-cuts
of fullerene graphs of sizes at most 6 is known. In the paper we study cyclic 7-edge connectivity of fullerene graphs, distinguishing
between degenerate and non-degenerate cyclic edge-cuts, regarding the arrangement of the 12 pentagons. We prove that if there
exists a non-degenerate cyclic 7-edge-cut in a fullerene graph, then the graph is a nanotube unless it is one of the two exceptions
presented. We determined that there are 57 configurations of degenerate cyclic 7-edge-cuts, and we listed all of them. 相似文献
90.
Zalar P Kamkar D Naik R Ouchen F Grote JG Bazan GC Nguyen TQ 《Journal of the American Chemical Society》2011,133(29):11010-11013
Introduction of a DNA interlayer adjacent to an Al cathode in a polymer light-emitting diode leads to lower turn-on voltages, higher luminance efficiencies, and characteristics comparable to those observed using a Ba electrode. The DNA serves to improve electron injection and also functions as a hole-blocking layer. The temporal characteristics of the devices are consistent with an interfacial dipole layer adjacent to the electrode being responsible for the reduction of the electron injection barrier. 相似文献