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11.
Sadafumi NishiharaTomoyuki Akutagawa Tatsuo Hasegawa Shigeki FujiyamaToshikazu Nakamura Takayoshi Nakamura 《Journal of solid state chemistry》2002,168(2):661-667
Two polymorphs of monovalent [Ni(dmit)2]− (dmit2−=2-thioxo-1,3-dithiole-4,5-dithiolate) crystals A and B, (anilinium)(18-crown-6)[Ni(dmit)2], were prepared, and the structure and magnetic properties were investigated. In these crystals, the [Ni(dmit)2]− molecules form dimers, which arranged into chains between the supramolecular cation structure (anilinium)(18-crown-6). In crystal A, supramolecular cation formed a regular stack, inducing ladder structure of [Ni(dmit)2], whose magnetism had been well fitted by spin ladder equation with the spin gap of Δ=190 K. Crystal B is ca. 3% more densely packed compared to crystal A. Due to the dense packing, supramolecular cation stack is distorted, which prevented the intermolecular interaction between [Ni(dmit)2]− dimers in direction corresponds to the ladder-leg direction in crystal A. Reflecting the [Ni(dmit)2]− arrangement, crystal B showed a temperature dependence of magnetic susceptibility well reproduced by the singlet-triplet thermal activation model, whose antiferromagnetic exchange interaction (2J) was 140 K. 相似文献
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Sizwe J. Zamisa Patrick Ndungu Bernard Omondi 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(10):1100-1103
The reaction of 4,4′‐bipyridine with copper acetate in the presence of 4‐nitrophenol led to the formation of the title compound, {[Cu(CH3COO)2(C10H8N2)]·C6H5NO3·2H2O}n. The complex forms a double‐stranded ladder‐like coordination polymer extending along the b axis. The double‐stranded polymers are separated by 4‐nitrophenol and water solvent molecules. The two CuII centres of the centrosymmetric Cu2O2 ladder rungs have square‐pyramidal coordination environments, which are formed by two acetate O atoms and two 4,4′‐bipyridine N atoms in the basal plane and another acetate O atom at the apex. The ladder‐like double strands are separated from each other by one unit‐cell length along the c axis, and are connected by the water and 4‐nitrophenol molecules through a series of O—H...O and C—H...O hydrogen‐bonding interactions and two unique intermolecular π–π interactions. 相似文献
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Synthesis,Thermal Behavior,and Dehydrogenation Kinetics Study of Lithiated Ethylenediamine
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Juner Chen Dr. Guotao Wu Prof. Zhitao Xiong Dr. Hui Wu Dr. Yong Shen Chua Dr. Wei Zhou Bin Liu Xiaohua Ju Prof. Ping Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(42):13636-13643
The lithiation of ethylenediamine by LiH is a stepwise process to form the partially lithiated intermediates LiN(H)CH2CH2NH2 and [LiN(H)CH2CH2NH2][LiN(H)CH2CH2N(H)Li]2 prior to the formation of dilithiated ethylenediamine LiN(H)CH2CH2N(H)Li. A reversible phase transformation between the partial and dilithiated species was observed. One dimensional {LinNn} ladders and three‐dimensional network structures were found in the crystal structures of LiN(H)CH2CH2NH2 and LiN(H)CH2CH2N(H)Li, respectively. LiN(H)CH2CH2N(H)Li undergoes dehydrogenation with an activation energy of 181±8 kJ mol?1, whereas the partially lithiated ethylenediamine compounds were polymerized and released ammonia at elevated temperatures. The dynamical dehydrogenation mechanism of the dilithiated ethylenediamine compounds was investigated by using the Johnson‐Mehl‐Avrami equation. 相似文献
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为玻色Hofstadter梯子模型引入交错跃迁,来扩展模型支持的量子流相.基于精确对角化和密度矩阵重整化群计算发现,无相互作用时,系统中包含横流相、涡旋相和纵流相;横流相来自均匀跃迁时Hofstadter梯子模型的Meissner相,纵流相是交错跃迁时才可见的流相.强相互作用极限下系统的超流区也包含横流相、纵流相和涡旋相,但存在更多的相变级数;超流区的横流相、纵流相之间存在相变但Mott区的不存在,把Mott区的"横、纵流相"称为Mott-均匀相,在Mott区只存在均匀相和涡旋相.跃迁的交错会压缩涡旋相存在的区域,使Mott区最终只剩下均匀相;跃迁的交错不仅能驱动Mott-超流相变,还使磁通的改变也能够驱动系统的Mott-超流相变.对这一系统的研究丰富了磁通系统中的量子流相,同时为研究拓扑流特性提供了模型支持. 相似文献
18.
ZHAN You-Bang 《理论物理通讯》2006,45(2):275-278
In this paper, two schemes for teleporting an unknown three-particle
three-level entangled state are proposed. In the first scheme, two partial three-particle three-level entangled states are used as the quantum
channels, while in the second scheme, three two-particle three-level
non-maximally entangled states are employed as quantum channels. It is shown that the teleportation can be successfully realized with certain
probability, for both two schemes, if a receiver adopts some appropriate
unitary transformations. It is shown also that the successful probabilities
of these two schemes are different. 相似文献
19.
Population Dynamics and Emission Spectrum of a Cascade Three-Level Jaynes-Cummings Model with Intensity-Dependent Coupling in a Kerr-like Medium 总被引:1,自引:0,他引:1
ZHOU Qing-Chun 《理论物理通讯》2006,45(4):727-730
By using the method of eigenvectors, the atomic populations and emission spectrum are investigated in a system that consists of a cascade three-level atom resonantly interacting with a single-mode field in a Kerr-like medium.The atom and the field are assumed to be initially in the upper atomic state and the Fock state, respectively. Results for models with intensity-dependent coupling and with intensity-independent coupling are compared. It is found that both population dynamics and emission spectrum show no indications of atom-field decoupling in the strong field limit if the intensity-dependent coupling is taken into account. 相似文献
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