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131.
Nonlinear Dynamics - Theoretical studies suggest that dispersion and repulsion are two important interactions that occur within non-polar particles. Enlightened by this, we propose a simple model... 相似文献
132.
采用原位共生长化学气相沉积法,以Co3O4、MoO3、Se粉末为前驱物,710℃下在SiO2衬底上生长掺钴MoSe2纳米薄片,分析讨论氢气含量对其生长及调节机理的影响.表面形貌分析表明,氢气的引入促进了成核所需的氧硒金属化合物以及横向生长中需要的CoMoSe化合物分子的生成;AFM(Atomic Force Microscope)结果表明氢气有利于生长单层二维超薄掺钴MoSe2.随着Co3O4前驱物用量的增加,样品的拉曼和PL(Photoluminescence)谱图分别表现出红移和蓝移现象,带隙实现从1.52—1.57 eV的调制.XPS(X-ray photoelectron spectroscopy)结果分析得到Co的元素组分比为4.4%.通过SQUID-VSM(Superconducting QUantum Interference Device)和器件电学测试分析了样品的磁电特性,结果表明Co掺入后MoSe2由抗磁性变为软磁性;背栅FETs器件的阈值电压比纯MoSe2向正向偏移5 V且关态电流更低;为超薄二维材料磁电特性研究及应用拓展提供了基础探索. 相似文献
133.
Chen Li Chen Yu Miao Lili Gao Yiming Di Junwei 《Journal of Solid State Electrochemistry》2020,24(2):411-420
Journal of Solid State Electrochemistry - In this work, we reported the photocurrent switching effect on BiVO4 semiconductor as well as its application for construction of a new cathodic... 相似文献
134.
Chen Dan Dan He Zhi Qiang Wang Min Wu Di Chen Xiang Ying Zhang Zhong Jie 《Journal of Solid State Electrochemistry》2020,24(3):641-654
Journal of Solid State Electrochemistry - In the present work, we demonstrate a strategy of combining boron doping and porosity engineering for a highly modulated carbon component and pore... 相似文献
135.
Atika Muhammad Dr. Graziano Di Carmine Luke Forster Dr. Carmine D'Agostino 《Chemphyschem》2020,21(11):1101-1106
Solvent effects in homogeneous catalysis are known to affect catalytic activity. Whilst these effects are often described using qualitative features, such as Kamlet-Taft parameters, experimental tools able to quantify and reveal in more depth such effects have remained unexplored. In this work, PFG NMR diffusion and T1 relaxation measurements have been carried out to probe solvent effects in the homogeneous catalytic reduction of propionaldehyde to 1-propanol in the presence of aluminium isopropoxide catalyst. Using data on diffusion coefficients it was possible to estimate trends in aggregation of different solvents. The results show that solvents with a high hydrogen-bond accepting ability, such as ethers, tend to form larger aggregates, which slow down the molecular dynamics of aldehyde molecules, as also suggested by T1 measurements, and preventing their access to the catalytic sites, which results in the observed decrease of catalytic activity. Conversely, weakly interacting solvents, such as alkanes, do not lead to the formation of such aggregates, hence allowing easy access of the aldehyde molecules to the catalytic sites, resulting in higher catalytic activity. The work reported here is a clear example on how combining traditional catalyst screening in homogeneous catalysis with NMR diffusion and relaxation time measurements can lead to new physico-chemical insights into such systems by providing data able to quantify aggregation phenomena and molecular dynamics. 相似文献
136.
G. Di Lonardo L. Fusina A. Trombetti Ian M. Mills 《Journal of Molecular Spectroscopy》1982,92(2):298-325
The ir absorption of gaseous 15NH3 between 510 and 3040 cm?1 was recorded with a resolution of 0.06 cm?1. The ν2, 2ν2, 3ν2, ν4, and ν2 + ν4 bands were measured and analyzed on the basis of the vibration-rotation Hamiltonian developed by V. ?pirko, J. M. R. Stone, and D. Papou?ek (J. Mol. Spectrosc.60, 159–178 (1976)). A set of effective molecular parameters for the ν2 = 1, 2, 3 states was derived, which reproduced the transition frequencies within the accuracy of the experimental measurements. For ν4 and ν2 + ν4 bands the standard deviation of the calculated spectrum is about four times larger than the measurements accuracy: a similar result was found for ν4 in 14NH3 by ?. Urban et al. (J. Mol. Spectrosc.79, 455–495 (1980)). This result suggests that the present treatment takes into account only the most significant part of the rovibration interaction in the doubly degenerate vibrational states of ammonia. 相似文献
137.
The conservation law of radiance as a suitable tool for investigation of radiation transfer processes between two systems
is treated. Original proofs of this law are given and its deep thermodynamical foundation is pointed out. Finally, applications
to general problems of power coupling and particularly to the radiation transfer from incoherent sources (LED) into multimode
optical fibres are carried out. 相似文献
138.
139.
In this paper we present several results about local MV-algebras, extending existing results given for MV-chains. The role
of local MV-algebras in sheaf representation and weak boolean product is stressed and the relationship of local MV-algebras
with varieties of MV-algebras is analyzed.
Presented by S. Pulmannova.
Received November 11, 2005; accepted in final form December 20, 2005. 相似文献
140.
This paper studies the cascading failure on random networks and
scale-free networks by introducing the tolerance parameter of edge
based on the coupled map lattices methods. The whole work focuses on
investigating some indices including the number of failed edges,
dynamic edge tolerance capacity and the perturbation of edge. In
general, it assumes that the perturbation is attributed to the
normal distribution in adopted simulations. By investigating the
effectiveness of edge tolerance in scale-free and random networks,
it finds that the larger tolerance parameter λ can more
efficiently delay the cascading failure process for scale-free
networks than random networks. These results indicate that the
cascading failure process can be effectively controlled by
increasing the tolerance parameter λ. Moreover, the
simulations also show that, larger variance of perturbation can
easily trigger the cascading failures than the smaller one. This
study may be useful for evaluating efficiency of whole traffic
systems, and for alleviating cascading failure in such systems. 相似文献