全文获取类型
收费全文 | 375篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
化学 | 157篇 |
晶体学 | 3篇 |
力学 | 34篇 |
数学 | 35篇 |
物理学 | 148篇 |
出版年
2021年 | 5篇 |
2020年 | 7篇 |
2019年 | 8篇 |
2018年 | 7篇 |
2017年 | 13篇 |
2016年 | 16篇 |
2015年 | 8篇 |
2014年 | 9篇 |
2013年 | 15篇 |
2012年 | 20篇 |
2011年 | 29篇 |
2010年 | 22篇 |
2009年 | 22篇 |
2008年 | 14篇 |
2007年 | 18篇 |
2006年 | 7篇 |
2005年 | 6篇 |
2004年 | 3篇 |
2003年 | 9篇 |
2002年 | 8篇 |
2001年 | 20篇 |
2000年 | 8篇 |
1999年 | 7篇 |
1998年 | 2篇 |
1996年 | 2篇 |
1994年 | 5篇 |
1993年 | 7篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 7篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1981年 | 2篇 |
1980年 | 5篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 5篇 |
1970年 | 2篇 |
1968年 | 2篇 |
1967年 | 3篇 |
1966年 | 2篇 |
1961年 | 2篇 |
1960年 | 1篇 |
1959年 | 3篇 |
排序方式: 共有377条查询结果,搜索用时 31 毫秒
71.
A nonlinear theory of self-oscillation in crossed electric and magnetic fields is worked out. Effects of the magnetic field intensity, sample dimensions, and surface recombination rate on the generation conditions of coherent (monochromatic) self-oscillations are studied. A domain model of coherent self-oscillations excited under transvere breakdown and strong magnetoconcentration effect is proposed. Numerical calculations for n-InSb (T = 77 K) are carried out. Coherent self-oscillations are shown to be induced for frequencies ~ 1010 Hz. 相似文献
72.
M E Belov M V Gorshkov K Alving R D Smith 《Rapid communications in mass spectrometry : RCM》2001,15(21):1988-1996
When combined with on-line separations (e.g., capillary liquid chromatography (LC)), Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) provides a powerful tool for biological applications, and particularly proteomic studies. The sensitivity, dynamic range, and duty cycle provided by FTICR-MS have been shown to be increased by ion trapping and accumulation in a two-dimensional (2D) radio-frequency (rf)-only multipole positioned externally to an FTICR cell. However, it is important that ions be detected across the desired m/z range without a significant bias. In this work we found that pressure inside the accumulation rf-quadrupole plays an important role in obtaining "unbiased" ion accumulation. Pressure optimization was performed in both pulsed and continuous modes. It was found that unbiased accumulation in a 2D rf-only quadrupole could be achieved in the pressure range of 5 x 10(-4) to 5 x 10(-3) Torr. External ion accumulation performed at the optimal pressure resulted in an increase in both the spectrum acquisition rates and dynamic range. 相似文献
73.
T. N. Makar'eva I. A. Gorshkova B. A. Gorshkov A. I. Kalinovskii V. A. Stonik 《Chemistry of Natural Compounds》1987,22(4):411-415
Five new sulfated derivatives of sokotrasterol and halistanol have been obtained: 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate); 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate) 23-palmitate; 24,25-dimethyl-5-cholestane-2,3,6-triol 3-(sodium sulfate); 24,25-dimethyl-5-cholestane-2,3,6-triol 6-(sodium sulfate); and 24,25-dimethyl-5-cholestane-2,3,6-triol 2,6-di(sodium sulfate). The inhibiting and membranolytic properties of the polysulfated steroids from sponges and their derivatives have been studied. It has been shown that physiological activity in this series of compounds depends on biphilicity.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 441–445, July–August, 1986. 相似文献
74.
Tsybin YO Håkansson P Budnik BA Haselmann KF Kjeldsen F Gorshkov M Zubarev RA 《Rapid communications in mass spectrometry : RCM》2001,15(19):1849-1854
New low-energy electron injection systems based on indirectly heated dispenser cathodes facilitate electron capture dissociation (ECD) in Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. In this joint report, details are presented of the design and performance of these systems on two commercial FTICR instruments, 9.4 T Bruker BioAPEX in Uppsala and 4.7 T IonSpec Ultima in Odense. New results include obtaining meaningful one-scan MS/MS data for isolated precursor ions with millisecond irradiation times. The ECD rate improvement is not only due to the larger total electron current, but the larger emitting area as well. 相似文献
75.
76.
T. Yu. Samgina V.A. Gorshkov K.A. Artemenko S.V. Kovalev S.V. Ogourtsov R. A Zubarev A.T. Lebedev 《Rapid communications in mass spectrometry : RCM》2010,24(12):1749-1754
Hyla arborea schelkownikowi is one of the leaf frog species inhabiting the southern territories of Russia and the former USSR. This frog species is a member of the Hylidae Rafinesque, 1815 batrachians family. The present study deals with the previously uninvestigated peptidome of the Hyla arborea schelkownikowi skin secretion. Nano‐electrospray ionization Fourier transform mass spectrometry (nanoESI‐FTMS) of the skin secretion, in the intact form and after acetylation, was selected as the general method of analysis. Electron‐capture dissociation (ECD) and collision‐induced dissociation (CID) fragmentation were both employed, while de novo sequencing was performed by manual interpretation of the MS data. The suppression of the cyclization of b‐ions in the mass spectrometer by the acetylation reaction proved to be very efficient for the de novo sequencing of short peptides. Ten skin peptides were found and all of them, except for bradykinin, had not previously been reported. Six of the peptides belong to the tryptophyllins and related peptides, while three peptides are similar to the aureins. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
77.
78.
Gennady P. Berman Alan R. Bishop Boris M. Chernobrod Dinh C. Nguyen Vyacheslav N. Gorshkov 《Optics Communications》2007,280(2):264-270
A new concept of a free space, high-speed (Gbps) optical communication system based on spectral encoding of radiation from a broadband pulsed laser is developed. It is shown that, in combination with the use of partially coherent laser beams and a relatively slow photosensor, scintillations can be suppressed by orders of magnitude for distances of more than 10 km. 相似文献
79.
M. Yu. Gorshkov N. M. Bogdanovich A. D. Neuimin L. A. Dunyushkina A. V. Kuz’min A. A. Pankratov 《Russian Journal of Electrochemistry》2007,43(9):987-996
The cathodic overvoltage of composite cathodes 50 wt % La0.8Sr0.2MnO3 (LSM) + 50 wt % La10Ge6O27 (LGO) (further on, LSM-LGO), LSM-SSZ (Zr0.835Sc0.165O2?δ), Ag-Pd-LGO, and Ag-Pd-SSZ in contact with the LGO electrolyte is measured. The temperature dependences of the polarization conductivity and the working-current densities of the same composite cathodes are investigated. The study is performed at 700–900°C. A comparison with the SSZ electrolyte is conducted. The chemical interaction in the LSM-LGO composition is studied. It is demonstrated that the interaction of lanthanum-strontium manganite with lanthanum germanate occurs with the dissolution of the initial phases in one another and with the formation of fresh phases at elevated temperatures. Coefficients of linear thermal expansion of the LGO and SSZ electrolytes and the LSM, LSM-LGO, and LSM-SSZ electrode materials are compared at 40–900°C. Most of the studied electrodes in contact with the LGO electrolyte demonstrate thermomechanical stability and high electrochemical activity. 相似文献
80.
A. V. Gorshkov M. V. Gorshkov I. G. Rozdina I. A. Tarasova N. N. Filatova V. V. Evreinov 《Polymer Science Series A》2010,52(3):340-347
The potentials inherent in the method of critical chromatography of macromolecules combined with mass spectrometry for the
study of the most complicated characteristic of the macromolecular structure—the determination of the position (the number)
of a defect unit or functional group in a sequence of chain units—are considered. Polyurethanes based on poly(propylene oxide)
oligomers were used as research objects. Such macromolecules contain a small amount of urethane groups in a chain that differ
from mainchain units in the energy of interaction with the surface. Variation in the molecular-mass distribution of the initial
poly(propylene oxide) oligomers makes it possible to prepare linear polyurethane macromolecules with different positions of
urethane groups. Critical chromatography offers a way to separate macromolecules with different amounts of urethane groups
and positions of these groups in chains. 相似文献