全文获取类型
收费全文 | 210篇 |
免费 | 3篇 |
国内免费 | 2篇 |
专业分类
化学 | 121篇 |
晶体学 | 2篇 |
力学 | 4篇 |
数学 | 3篇 |
物理学 | 85篇 |
出版年
2018年 | 2篇 |
2017年 | 2篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 9篇 |
2012年 | 7篇 |
2011年 | 12篇 |
2010年 | 7篇 |
2009年 | 13篇 |
2008年 | 12篇 |
2007年 | 13篇 |
2006年 | 9篇 |
2005年 | 8篇 |
2004年 | 12篇 |
2003年 | 13篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1981年 | 4篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1970年 | 1篇 |
1969年 | 2篇 |
1967年 | 2篇 |
1958年 | 1篇 |
排序方式: 共有215条查询结果,搜索用时 15 毫秒
131.
A novel solid state reduction of sulfoxides including methionine sulfoxide to the corresponding sulfides by iodide/organic acid system is described. 相似文献
132.
Sanchez LM Curtis ME Bracamonte BE Kurita KL Navarro G Sparkman OD Linington RG 《Organic letters》2011,13(15):3770-3773
Analysis of substrates directly on solid phase resins without the need for separate cleavage conditions remains an outstanding challenge in the field of solid phase synthesis. We now present the first example of simultaneous cleavage and mass spectrometric analysis of peptides from solid supports using direct analysis in real time (DART) mass spectrometry. We have shown that this method is compatible with a diverse array of solid phase resins and is suitable for analysis of both peptides and organic substrates. 相似文献
133.
The electronic structure of low-density n-type SrTiO3 δ-doped heterostructures is investigated by angular dependent Shubnikov-de Haas oscillations. In addition to a controllable crossover from a three- to two-dimensional Fermi surface, clear beating patterns for decreasing dopant layer thicknesses are found. These indicate the lifting of the degeneracy of the conduction band due to subband quantization in the two-dimensional limit. Analysis of the temperature-dependent oscillations shows that similar effective masses are found for all components, associated with the splitting of the light electron pocket. The dimensionality crossover in the superconducting state is found to be distinct from the normal state, resulting in a rich phase diagram as a function of dopant layer thickness. 相似文献
134.
Terashima T Kurita N Tomita M Kihou K Lee CH Tomioka Y Ito T Iyo A Eisaki H Liang T Nakajima M Ishida S Uchida S Harima H Uji S 《Physical review letters》2011,107(17):176402
We show that the Fermi surface (FS) in the antiferromagnetic phase of BaFe(2)As(2) is composed of one hole and two electron pockets, all of which are three dimensional and closed, in sharp contrast to the FS observed by angle-resolved photoemission spectroscopy. Considerations on the carrier compensation and Sommerfeld coefficient rule out existence of unobserved FS pockets of significant sizes. A standard band structure calculation reasonably accounts for the observed FS, despite the overestimated ordered moment. The mass enhancement, the ratio of the effective mass to the band mass, is 2-3. 相似文献
135.
Harada A Enomoto K Takahide Y Kimata M Yakabe T Kodama K Satsukawa H Kurita N Tsuchiya S Terashima T Uji S 《Physical review letters》2011,107(7):077002
We report the first observation of a single-vortex flow in a mesoscopic superconductor. A flow of a single vortex is successfully controlled by an rf current superimposed on a dc current, evidence of which is provided by voltage steps in current-voltage (I-V) characteristics. Irrespective of the number of vortices confined to the disk, we unambiguously observe that when a single vortex inside the disk is driven out of the disk, another vortex enters the disk similarly to two balls colliding in billiards: only one vortex passes through the Al disk at the same time in mesoscopic systems. 相似文献
136.
Galvanic cell-type hydrogen sensor for high temperature use is now available thanks to the discovery of oxide-type proton
conducting solid electrolyte such as acceptor-doped perovskite-type oxides. In order to develop the practically functional
hydrogen sensor based on these electrolytes, the electrochemical properties of these oxides should be understood as a function
of hydrogen and oxygen potentials at the temperature range where the sensor is to be used. In this review, the properties
of indium-doped calcium zirconate (represented by the composition CaZr0.9In0.1O3–δ) known as, among these oxides, the most chemically stable and mechanically strong were explained briefly on the basis of
the thermodynamics of the crystal imperfections. Then the structure of hydrogen sensor for molten aluminum and that for molten
copper, which were designed to make the best use of the properties of the electrolyte for the respective process conditions,
were shown. Lastly, the performance of these sensors examined in the laboratory scale and the practical industrial conditions
was overviewed.
Paper presented at the 9th EuroConference on Science and Technology of Ionics, Rhodes, Greece, Sept. 15 – 21, 2003. 相似文献
137.
138.
V.I. Danilov V.V. Dailidonis D.M. Hovorun N. Kurita Y. Murayama T. Natsume A.I. Potopalsky L.A. Zaika 《Chemical physics letters》2006,430(4-6):409-413
The stable structures and electronic properties for the berberine cation as well as possible ammonium, carbinol and amino-aldehyde forms of protoberberine salts in the presence of hydroxyl ions were investigated by the B3LYP/6-31G(d,p) and MP2/6-31++G(d,p) methods. The geometry optimizations by both methods lead to the nonplanar propeller-twisted and buckled structure for the all forms. The obtained bond lengths and bond angles agree with the experimental values. The comparison of total energies elucidates that the amino-aldehyde form is the most preferable tautomer in gas phase, while the carbinol form is less stable. The least stable tautomer is the ammonium form. 相似文献
139.
Photocatalytic oxidation of organic adsorbates on anatase TiO2 films has been examined in different atmospheres of humid air, dry air and vacuum. The photocatalytic oxidation was observed by IR absorption spectroscopy (IRAS) with a multiple-internal-reflection (MIR) geometry. The photocatalytic oxidation is the fastest in the air at a humidity of 70% where oxygen and water vapor are consuming to produce OH radicals and O2− anions on the TiO2 surface with the UV exposure. In the dry air, a rate of the photocatalytic oxidation is almost 30% of that in the humid air, where only O2− anions oxidize the organic adsorbates. In vacuum, on the other hand, it is negligible, which suggests that adsorbed H2O molecules do not play an important role in the photocatalytic reaction. It is suggested that an addition of the water vapor is necessary to achieve the higher catalytic activity. 相似文献
140.
Hideo Fujikake Masashi Kuboki Takeshi Murashige Hiroto Sato Hiroshi Kikuchi Taiichiro Kurita Fumio Sato 《Liquid crystals》2004,31(7):989-992
This paper discusses thermal phase transitions in a nematic liquid crystal material, filling a highly strained porous polyolefin film. Ruptured and aligned polymer fibrils, whose minimum diameter reaches several tens of nm, formed polymer networks in the porous film. From observations of temperature-controlled composite films using a polarizing microscope, it was noted that the isotropic-to-nematic phase transition temperatures of submicron liquid crystal domains, located in or near molecularly aligned streak-like polymer areas, were significantly higher than those located at some distance from these areas. It was assumed that the highly aligned polymer chains in the fine fibrils promote the nematic phase of the liquid crystal. The stretched porous polymer, exhibiting spatial ordering on a submicron scale, is thus suitable for the control of thermal phase transitions in a liquid crystal. 相似文献