全文获取类型
收费全文 | 697篇 |
免费 | 1篇 |
专业分类
化学 | 392篇 |
晶体学 | 53篇 |
力学 | 12篇 |
数学 | 13篇 |
物理学 | 228篇 |
出版年
2022年 | 7篇 |
2021年 | 13篇 |
2020年 | 13篇 |
2019年 | 17篇 |
2018年 | 18篇 |
2017年 | 20篇 |
2016年 | 18篇 |
2015年 | 11篇 |
2014年 | 17篇 |
2013年 | 29篇 |
2012年 | 19篇 |
2011年 | 36篇 |
2010年 | 29篇 |
2009年 | 42篇 |
2008年 | 23篇 |
2007年 | 20篇 |
2006年 | 21篇 |
2005年 | 19篇 |
2004年 | 27篇 |
2003年 | 16篇 |
2002年 | 15篇 |
2001年 | 12篇 |
2000年 | 10篇 |
1999年 | 7篇 |
1998年 | 12篇 |
1997年 | 13篇 |
1996年 | 20篇 |
1995年 | 10篇 |
1994年 | 18篇 |
1993年 | 7篇 |
1991年 | 5篇 |
1990年 | 8篇 |
1989年 | 9篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1983年 | 4篇 |
1979年 | 8篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1976年 | 8篇 |
1975年 | 5篇 |
1974年 | 9篇 |
1973年 | 5篇 |
1972年 | 8篇 |
1971年 | 8篇 |
1970年 | 10篇 |
1969年 | 7篇 |
1968年 | 8篇 |
1967年 | 6篇 |
排序方式: 共有698条查询结果,搜索用时 15 毫秒
591.
V. V. Danilov M. V. Artem’ev A. V. Baranov A. O. Orlova M. V. Mukhina A. I. Khrebtov 《Optics and Spectroscopy》2011,110(6):897-902
Liquid-crystal (LC) composites based on a combination of different acrylates and pentylcyanobiphenyl and containing CdSe/ZnS
semiconductor quantum nanorods have been investigated. Samples of electro-optical cells with planar or homeotropic structures
(depending on the acrylate type) have been obtained. The morphology of LC composite formation has been studied using luminescence
techniques. It is shown that these composites are gel-like LC media, where the formation of dispersed and network structures
in the cells plays a stabilizing role. The role of the electron transfer reactions during polymerization and the features
of the kinetics of the Freedericksz effect (reorientation in an electric field) are discussed. 相似文献
592.
Natalja Orlova Irena Nikolajeva Aleksandrs Pu
kins Sergey Belyakov Elena Kirilova 《Molecules (Basel, Switzerland)》2021,26(9)
New substituted azomethines of benzanthrone with heterocyclic substituents were synthesized by condensation reaction of 3-aminobenzo[de]anthracen-7-one with appropriate aromatic aldehydes. The resulting imines were reduced with sodium borohydride to the corresponding amines, the luminescence of which is more pronounced in comparison with the initial azomethines. The novel benzanthrone derivatives were characterized by NMR, IR, MS, UV/Vis, and fluorescence spectroscopy. The structure of three dyes was studied by the X-ray single crystal structure analysis. The solvent effect on photophysical behaviors of synthesized imines and amines was investigated. The obtained compounds absorb at 420–525 nm, have relatively large Stokes shifts (up to 150 nm in ethanol), and emit at 500–660 nm. The results testify that emission of the studied compounds is sensitive to the solvent polarity, exhibiting negative fluorosolvatochromism for the synthesized azomethines and positive fluorosolvatochromism for the obtained amines. The results obtained indicate that the synthesized compounds are promising as luminescent dyes. 相似文献
593.
Maria Orlova Lukas Perfler Martina Tribus Petr Salnikov Benoit Glorieux Albina Orlova 《ChemInform》2016,47(17):no-no
In view of a known structural phase transition at 800—875 °C and the by 10 times increased luminescence of Mn2+ in the high‐temperature phase, low‐ (LT) and high‐temperature (HT) polymorphs of CaMn0.5Zr1.5(PO4)3 are prepared by sol—gel reaction of Mn(O‐Ac)2, Ca(NO3)2, ZrOCl2, and NH4H2PO4 in ethylene glycol followed by a final annealing (700 or 900 °C, 20 h, resp.). 相似文献
594.
Dr. Anna V. Orlova Renato R. Andrade Prof. Dr. Clarissa O. da Silva Alexander I. Zinin Dr. Leonid O. Kononov 《Chemphyschem》2014,15(1):195-207
Optical rotation of aqueous solutions of D ‐levoglucosan was studied experimentally in the 0.03–4.0 mol L?1 concentration range and a nonlinear concentration dependence of specific optical rotation (SR) was revealed. Discontinuities observed in the concentration plot of SR (at 0.1, 0.3, 0.5, 1.0, and 2.0 mol L?1) are well correlated with those found by static and dynamic light scattering and identify concentration ranges in which different solution domains (supramers) may exist. The average SR experimental value for a D ‐levoglucosan aqueous solution ([α]D28 ?58.5±8.7 deg dm?1 cm?3 g?1) was found to be in good agreement with values obtained by theoretical calculation (TD‐DFT/GIAO) of SR for 15 different conformers revealed by conformational sampling at the PCM/B3LYP/6‐311++G(2d,2p)//B3LYP/6‐31+G(d,p) level, which were shown to be strongly affected by the solvation microenvironment (0, 1, 2, and 3 explicit solvent molecules considered) due to local geometrical changes induced in the solute molecule. This exceptionally high sensitivity of SR makes polarimetry a unique method capable of sensing changes in the structure of supramers detected in this study. 相似文献
595.
An approximate solution is obtained to the problem of inertialess periodic flow of fluid with a variable structure in a pipe of circular cross section. A study is made of the effect of the parameters which define the kinetics of the variations in the structure and the fluctuations in the pressure gradient on the effective viscosity and the other mean hydrodynamic characteristics. A comparison is made between the solutions to the problems of the flow of a thixotropic and a nonlinearly viscous fluid. The results are discussed in connection with their application to the circulation of the blood.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 3–9, January–February, 1987. 相似文献
596.
L. I. Galanina N. S. Zelenskaya V. M. Lebedev N. V. Orlova A. V. Spassky 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(7):920-929
An important property—the dynamic deformation of B* light aligned nuclei—is investigated for the nuclear reactions A(x, y)B* → γ + B 0 by measuring the y-γ correlations. Dynamic deformation is determined from the orientation tensors of multipolar moments. Normalization constants of the contributions from even-rank orientation tensors are determined from the condition of coincidence between dynamic and static deformations of the B* nucleus for θ y = 0°. Experimental dynamic deformations of 12C(2+) nuclei caused by the inelastic scattering of α particles and deuterons are determined, along with the 10Be(2+) nuclei formed in reaction 9Be(d, p)10Be(2+). It is shown that the dynamic deformation of the aligned nuclei depends on how they are formed and their structure, and evolves substantially when the angle θ y is varied. 相似文献
597.
L. I. Galanina N. S. Zelenskaya I. A. Konyukhova V. M. Lebedev N. V. Orlova A. V. Spassky 《Physics of Atomic Nuclei》2013,76(11):1415-1422
The double-differential cross sections for the reaction 24Mg(d, dγ 1.369)24Mg at the projectiledeuteron energy of E d = 15.3 MeV weremeasured for deuteron emission angles in the forward hemisphere. All even spin-tensor components of the density matrix for the 2+ state of the 24Mg nucleus at 1.369 MeV were reconstructed, and its orientation properties were determined. These experimental results were compared with the results of calculations based on various versions of the coupled-channel method. 相似文献
598.
A. V. Zhikharev I. N. Klimova A. Yu. Drozdov V. Ya. Bayankin N. M. Sozonova N. A. Orlova 《Physics of the Solid State》2013,55(10):2001-2010
The influence of the laser radiation power density on the changes in the composition and mechanical properties of surface layers of Cu50Ni50 foils has been investigated using X-ray photoelectron spectroscopy, scanning probe microscopy, X-ray diffraction, and microhardness measurements. It has been found that, after laser irradiation, the redistribution of elements occurs in the surface layer with a thickness of ~30 nm on the irradiated side of the foil. It has been revealed that there are microdistortions in the crystal lattice of the alloy, microdeformations of grains, and variations in the microhardness of the irradiated surface. The mechanisms explaining the observed changes in the foils after laser irradiation have been proposed. 相似文献
599.
B. K. Kardashev T. S. Orlova B. I. Smirnov A. Gutierrez J. Ramirez-Rico 《Physics of the Solid State》2013,55(9):1884-1891
Microstructural characteristics and amplitude dependences of the Young modulus E and of internal friction (logarithmic decrement δ) of bio-carbon matrices prepared from beech tree wood at different carbonization temperatures T carb ranging from 600 to 1600°C have been studied. The dependences E(T carb) and δ(T carb) thus obtained revealed two linear regions of increase of the Young modulus and of decrease of the decrement with increasing carbonization temperature, namely, ΔE ~ AΔT carb and Δδ ~ BΔT carb, with A ≈ 13.4 MPa/K and B ≈ ?2.2 × 10?6 K?1 for T carb < 1000°C and A ≈ 2.5 MPa/K and B ≈ ?3.0 × 10?7 K?1 for T carb > 1000°C. The transition observed in the behavior of E(T carb) and δ(T carb) at T carb = 900–1000°C can be assigned to a change of sample microstructure, more specifically, a change in the ratio of the fractions of the amorphous matrix and of the nanocrystalline phase. For T carb < 1000°C, the elastic properties are governed primarily by the amorphous matrix, whereas for T carb > 1000°C the nanocrystalline phase plays the dominant part. The structurally induced transition in the behavior of the elastic and microplastic characteristics at a temperature close to 1000°C correlates with the variation of the physical properties, such as electrical conductivity, thermal conductivity, and thermopower, reported in the literature. 相似文献
600.
V. I. Danilov L. B. Zuev E. V. Letakhova D. V. Orlova I. A. Okhrimenko 《Journal of Applied Mechanics and Technical Physics》2006,47(2):298-305
Macrolocalization, which accompanies the process of plastic deformation beginning from the yield point and ending by fracture,
is determined by the staged character of material-loading diagrams. The evolution of localization patterns in a plastic flow
of body-centered cubic vanadium alloy, hexagonal close-packed magnesium alloy, tetragonal tin, and face-centered cubic submicrocrystalline
aluminum is analyzed within this concept.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 2, pp. 176–184, March–April, 2006. 相似文献