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111.
The mechanism of the FA/O chelating agent in the process of chemical mechanical polishing (CMP) is introduced. CMP is carried on a φ300 mm copper film. The higher polishing rate and lower surface roughness are acquired due to the action of an FA/O chelating agent with an extremely strong chelating ability under the condition of low pressure and low abrasive concentration during the CMP process. According to the results of several kinds of additive interaction curves when the pressure is 13.78 kPa, flow rate is 150 mL/min, and the rotating speed is 55/60 rpm, it can be demonstrated that the FA/O chelating agent plays important role during the CMP process. 相似文献
112.
对1064nm谐振腔增强型(RCE)光电探测器(PD)的光电响应特性进行了分析研究.利用MBE生长技术得到有源区分别为量子阱和量子点的1064nm RCE探测器的外延片,并对制作的探测器进行了各种光电特性测试.结果表明量子阱结构的RCE探测器量子效率峰值达到57%,谱线半宽6~7nm,峰值波长1059nm;而量子点结构的RCE探测器量子效率峰值达到30%,谱线半宽5nm,峰值波长1056nm.通过分析量子效率和吸收系数之间的关系,对两种结构器件的吸收进行了比较,发现虽然量子点探测器的吸收小,但通过合理设计共振腔等方法也可以达到较高的量子效率.两种结构的器件都有很好的I-V特性. 相似文献
113.
Lin‐Bao Zhang Xin‐Qi Hao Zhan‐Jiang Liu Xin‐Xiang Zheng Shou‐Kun Zhang Jun‐Long Niu Mao‐Ping Song 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(34):10150-10153
A highly efficient cobalt(II)‐catalyzed alkynylation/annulation of terminal alkynes assisted by an N,O‐bidentate directing group is described. This protocol is characterized by wide substrate scope utilizing cheap cobalt catalysts, and offers a new approach to 3‐methyleneisoindolin‐1‐one, which can be converted into an oxadiazine salt in one step. Moreover, the directing group could be removed in three steps. 相似文献
114.
Cheng X Niu L Zhao Y Zhou Z 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(4):907-914
The decomposition reaction pathways of o-pyridyl were investigated extensively at the B3LYP/6-311G** level. With the relative energies after zero-point energy correction, the potential energy surface was drawn out. The vibrational frequencies for all species were predicted and the reaction mechanism was elucidated utilizing vibrational frequencies and vibrational mode analysis. The primary products of o-pyridyl decomposition reactions are acetylene and cyanoacetylene. 相似文献
115.
NH and N-protected isoquinolones undergo Rh(III)-catalyzed oxidative olefination at the 8-position. Complementary redox-neutral olefination of such isoquinolones using internal alkynes was achieved under ruthenium catalysis. 相似文献
116.
W. Huang Z. L. Li Y. D. Peng S. Chen J. F. Zheng Z. J. Niu 《Journal of Solid State Electrochemistry》2005,9(5):284-289
A film of Ni(OH)2 deposited cathodically on a roughened nickel substrate consists of even nanoparticles, which were characterized by atomic-force microscopy (AFM). The mechanism of potential oscillations in the electrocatalytic oxidation of methanol on this film electrode in alkaline medium was studied in situ by means of Raman spectroscopy in combination with electrochemical measurements. The redox change of the nickel hydroxide film, the concentration distribution of methanol in the diffusion layer, and the oxidation products of methanol were characterized in situ by time-resolved, spatial-resolved, and potential-dependent Raman spectroscopy, respectively. Electrochemical reactions, i.e. methanol oxidation and periodic oxygen evolution, coupling with alternately predominant diffusion and convection mass transfer of methanol, account for the potential oscillations that occur during oxidation of methanol above its limiting diffusion current. This mechanism is totally different from that of methanol oxidation on platinum electrodes, for which surface steps, i.e. formation and removal of COad, are essential.This work is dedicated to Professor Gyorgy Horanyi on the occasion of his 70th birthday in recognition of his numerous contributions to field of electrochemical oscillations and electrocatalysis at Ni-hydroxide electrodes. 相似文献
117.
Jieni Li Henan Li Lai Liu Huizhen Yao Bingbing Tian Chenliang Su Haizhe Zhong Ye Wang Lifu Zhang Yumeng Shi 《化学:亚洲杂志》2019,14(16):2861-2868
Organometallic halide perovskites have attracted great research interest as light‐active materials for use in optoelectronics. Here, we report a high‐performance photoconductor based on a methylammonium lead iodide (MAPbI3) film that was prepared from a methylamine‐treated MAPbI3/PbI2 perovskite film. An ultrahigh responsivity of 3.6 A W?1 and detectivity of 5.4×1012 Jones were obtained for the film under 0.5 mW cm?2 white‐light illumination. In addition, under 420 nm light irradiation, the film exhibited its highest responsivity and detectivity of 30 A W?1 and 2.4×1014 Jones, respectively. The excellent photo‐response performance results from the improved electronic quality and suppressed nonradiative recombination channels of the treated perovskite thin film. 相似文献
118.
Jiai Hua Xiang Ma Pengtao Ma Jingping Wang Jingyang Niu 《Journal of Cluster Science》2013,24(3):689-700
A new compound H8[NaCu5Cl(H2O)3(B-α-AsW9O33)2] 24H2O (1) is synthetized by the reaction of the CuCl2 2H2O and Na27[NaAs4W40O140] 60H2O in aqueous solution, which is constructed from a {Cu5Na} hexagon moiety sandwiched by two trilacunary [B-α-AsW9O33]9? units. The structure is determined by single-crystal X-ray diffraction technique and further characterized by IR spectroscopy. Single-crystal X-ray diffraction analysis reveals that 1 is built by two trilacunary [B-α-AsW9O33]9? units incorporating a {Cu5Na} hexagon moiety and further linked to each other to form an infinitely extended 2-D network via Cu–O–W bridges. Notably, magnetic measurement demonstrates that the occurrence of intramolecular ferromagnetic Cu–Cu interactions within {Cu5Na} hexagon moiety. 相似文献
119.
Many quantum mechanical calculations indicate water molecules in the gas and liquid phase have much larger quadrupole moments than any of the common site models of water for computer simulations. Here, comparisons of multipoles from quantum mechanical∕molecular mechanical (QM∕MM) calculations at the MP2∕aug-cc-pVQZ level on a B3LYP∕aug-cc-pVQZ level geometry of a waterlike cluster and from various site models show that the increased square planar quadrupole can be attributed to the p-orbital character perpendicular to the molecular plane of the highest occupied molecular orbital as well as a slight shift of negative charge toward the hydrogens. The common site models do not account for the p-orbital type electron density and fitting partial charges of TIP4P- or TIP5P-type models to the QM∕MM dipole and quadrupole give unreasonable higher moments. Furthermore, six partial charge sites are necessary to account reasonably for the large quadrupole, and polarizable site models will not remedy the problem unless they account for the p-orbital in the gas phase since the QM calculations show it is present there too. On the other hand, multipole models by definition can use the correct multipoles and the electrostatic potential from the QM∕MM multipoles is much closer than that from the site models to the potential from the QM∕MM electron density. Finally, Monte Carlo simulations show that increasing the quadrupole in the soft-sticky dipole-quadrupole-octupole multipole model gives radial distribution functions that are in good agreement with experiment. 相似文献
120.
H. L. Cheng D. Y. Shi J. W. Zhao Z. D. Geng L. J. Chen P. T. Ma J. Y. Niu 《Russian Journal of Coordination Chemistry》2011,37(4):302-308
A novel 3D 3d–4f heterometallic polymer Pr4(H2O)9Cu3.5Cl0.5(Bpdc)6.5(OH)2 · 5H2O (I) (H2Bpdc = 2,2′-bipyridyl-5,5′-dicarboxylic acid) has been hydrothermally synthesized by the reaction of CuCl2 · 2H2O, PrCl3, H2Bpdc, TAA (TAA = 1H-tetrazolyl-1-acetic acid) and glacial acetic acid and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Single-crystal structural analysis shows that I displays an interesting heterometallic 3D coordination framework constructed from 2D praseodymium-oxygen layers and [Cu(Bpdc)2]3? and [CuCl(Bpdc)]2? pillars. The photofluorescence properties of I have been investigated. 相似文献