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101.
Volodymyr V. Lyubashenko 《Communications in Mathematical Physics》1995,172(3):467-516
An example of a finite dimensional factorizable ribbon Hopf -algebra is given by a quotientH=u
q
(g) of the quantized universal enveloping algebraU
q
(g) at a root of unityq of odd degree. The mapping class groupM
g,1
of a surface of genusg with one hole projectively acts by automorphisms in theH-moduleH
*g
, ifH
* is endowed with the coadjointH-module structure. There exists a projective representation of the mapping class groupM
g,n
of a surface of genusg withn holes labeled by finite dimensionalH-modulesX
1, ...,X
n
in the vector space Hom
H
(X
1 ... X
n
,H
*g
). An invariant of closed oriented 3-manifolds is constructed. Modifications of these constructions for a class of ribbon Hopf algebras satisfying weaker conditions than factorizability (including most ofu
q
(g) at roots of unityq of even degree) are described.This work was supported in part by the EPSRC research grant GR/G 42976. 相似文献
102.
103.
Dmytro S. Nesterov Volodymyr N. Kokozay Brian W. Skelton 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):m246-m248
The crystal structure of the title compound, triacetato‐1κO;3κ4O,O′‐(2,2′‐iminodiethanol)‐1κ3O,N,O′‐bis(μ‐2,2′‐iminodiethanolato)‐1κ2O:2κ6O,N,O′:3κ2O′‐cobalt(III)copper(II)zinc(II), [CoCuZn(C4H9NO2)2(C2H3O2)3(C4H11NO2)], shows a molecule with a triangular three‐metal core. The metal sites were refined with full occupancies, but the possibility that the Zn and Cu positions are actually mixed Cu/Zn sites cannot be excluded. The intermetallic Cu⋯Co and Co⋯Zn distances are 2.924 (3) and 2.906 (3) Å, respectively. The neutral molecules are held together by N—H⋯O hydrogen bonds involving amine groups from the 2,2′‐iminodiethanol ligands and acetate groups to build two‐dimensional layers. 相似文献
104.
Taras I. Chaban Volodymyr V. Ogurtsov Ihor G. Chaban Olena V. Klenina Josef D. Komarytsia 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1611-1620
Abstract 5,7-Dimethyl-3H-thiazolo[4,5-b]pyridine-2-one was obtained under the reaction of 4-iminothiazolidin-2-one with acetylacetone. Further structural modifications include the introduction of diversity at the N3 and C6 positions. The antioxidant activity of the synthesized compounds was evaluated in vitro by the method of scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the following free supplemental files: Additional figures] 相似文献
105.
106.
107.
108.
Dr. Piotr A. Guńka Dr. Anna Olejniczak Dr. Samuele Fanetti Prof. Dr. Roberto Bini Dr. Ines E. Collings Dr. Volodymyr Svitlyk Dr. Kamil F. Dziubek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(3):1094-1102
High-pressure behavior of hexamethylenetetramine (urotropine) was studied in situ using angle-dispersive single-crystal synchrotron X-ray diffraction (XRD) and Fourier-transform infrared absorption (FTIR) spectroscopy. Experiments were conducted in various pressure-transmitting media to study the effect of deviatoric stress on phase transformations. Up to 4 GPa significant damping of molecular librations and atomic thermal motion was observed. A first-order phase transition to a tetragonal structure was observed with an onset at approximately 12.5 GPa and characterized by sluggish kinetics and considerable hysteresis upon decompression. However, it occurs only in non-hydrostatic conditions, induced by deviatoric or uniaxial stress in the sample. This behavior finds analogies in similar cubic crystals built of highly symmetric cage-like molecules and may be considered a common feature of such systems. DFT computations were performed to model urotropine equation of state and pressure dependence of vibrational modes. The first successful Hirshfeld atom refinements carried out for high-pressure diffraction data are reported. The refinements yielded more realistic C−H bond lengths than the independent atom model even though the high-pressure diffraction data are incomplete. 相似文献
109.
Jonas Köhling Dr. Volodymyr Kozel Dr. Vladislav Jovanov Dr. Romana Pajkert Dr. Sergey N. Tverdomed Oleg Gridenco Malte Fugel Prof. Dr. Simon Grabowsky Prof. Dr. Gerd-Volker Röschenthaler Prof. Dr. Veit Wagner 《Chemphyschem》2019,20(5):665-671
A blue-light emitting material based on a boron complex containing heteroaromatic phosphonate ligand is synthesized and characterized. The Phospho-Fries rearrangement is used in the synthesis route of the ligand as a convenient method of introducing phosphonate groups into phenols. Structural, thermal and photophysical properties of the resulting oxazaborinin phosphonate compound have been characterized. DFT geometry optimizations were studied as well as the spatial position and symmetry of the HOMO and LUMO. Good thermal stability up to 250 °C enables vacuum deposition methods next to solution processing. Combining the work function with the optical band gap from UV-Vis measurements shows that band alignment is possible with standard contact materials. Photoluminescence reveals an emission peak at 428 nm, which is suitable for a blue light-emitter. 相似文献
110.
Volodymyr Buturlim Michał Falkowski Mykhaylo Paukov Oleksandra Koloskova Daria Drozdenko Milan Dopita 《哲学杂志》2019,99(15):1881-1898
Uranium Laves phase UTi2 does not exist in a pure form, but can be stabilised by the presence of hydrogen, which can be absorbed in concentration exceeding 5?H atoms/f.u. Low temperature specific heat, magnetic susceptibility, and resistivity indicate that UTi2H5 is a spin fluctuator close to the verge of magnetic ordering. Its susceptibility follows at high temperatures the Curie–Weiss law with U effective moment µeff[ ?= 3.1?µB/U and paramagnetic Curie temperature Θp = ?200 K. The temperature dependence of specific heat exhibits a pronounced and weakly field dependent upturn in Cp/T versus T below 10 K reflecting the effect of spin fluctuations. It can be described by an additional T½ term. The Sommerfeld coefficient γ = 256?mJ/mol K2 classifies the compound as a mid-weight heavy fermion. Spin fluctuations are affecting also electrical and thermal transport and thermoelectric power, which all resemble UAl2. A lattice anomaly at ≈ 240?K, attributed to the melting of hydrogen sublattice, reflects in most of bulk properties. 相似文献