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991.
Abstract

A new dinuclear copper(I) cluster complex, [(o-Tol)3PCuI2CuP(o-Tol)3(DMF)] (1) ((o-Tol)3P = tris(2- methylphenyl)phosphine, DMF = N, N′-dimethylformamide), has been synthesized and the crystal structure was determined by a single-crystal X-ray diffraction study. The dinuclear copper(I) cluster molecule containing an asymmetric Cu2I2P2O core and the dinuclear clusters are fused together by a strong π–π stacking interaction to form asupramolecular one-dimensional (1D) chain. After having compared the relevant complexes composed of CuI and monodentate triarylphosphine ligands, the impact of the substituent of the triarylphosphine ligand to the subsequent complex structure has also been discussed.Except for a strong π–π* bond, the complex 1 also exhibits a weak metal-to-ligand charge transfer (MLCT) absorption bond in the 430–530-nm region and displays a weak green-yellow emission when irradiated by ultraviolet (UV) light. The thermogravimetric analysis demonstrates that its thermal stability is good, and the corresponding PXRD analysis has revealed that the final, organic-free decomposed product is CuI.  相似文献   
992.
A new series of niobium phosphates with the composition of MxNb4P21717 (M=Li and Na, X=4; M=Zn, Ca, Mg, Sr and Ba, X=2) have been successfully synthesized. The powder X-ray diffraction (XRD) data of these isostructural compounds, was studied The powder Second Harmonic Generation (SHG) effects of these compounds were about twice of that of KH2PO4 (KDP).  相似文献   
993.

The degradation of pyrazinamide (PZA) by electron beam irradiation (EBI) was studied. It was found that the degradation of PZA was efficient with the removal rate of 99% for 0.2 mM PZA under 5 kGy, and the degradation kinetics followed pseudo-first-order kinetics. The presence of CO32?, HCO3?, NO3?, and fulvic acid inhibited the degradation of PZA. The addition of H2O2 or K2S2O8 effectively enhanced the degradation and mineralization of PZA. The scavenger experiments and quantum chemical calculations showed that ·OH was the primary reactive species in the degradation. The identification of intermediates and quantum chemical calculations illustrated the mechanism of degradation.

  相似文献   
994.
The development of efficient electrochemical seawater splitting catalysts for large-scale hydrogen production is of great importance. In this work, we report an amorphous Co-Mo-B film on Ni foam (Co-Mo-B/NF) via a facile one-step electrodeposition process. Such amorphous Co-Mo-B/NF possesses superior activity with a small overpotential of 199 mV at 100 mA cm−2 for a hydrogen evolution reaction in alkaline seawater. Notably, Co-Mo-B/NF also maintains excellent stability for at least 24 h under alkaline seawater electrolysis.  相似文献   
995.
总结了在神光Ⅲ原型激光装置上开展的一系列黑腔物理实验研究,从多个方面研究了黑腔内部等离子体状态和辐射场特性。用真空黑腔能量学研究获得了散射光、辐射温度和不同能段辐射流份额的定标规律,从能量学角度梳理和分析了整个激光黑腔相互作用过程。通过对黑腔中充入低密度低Z气体抑制了腔壁等离子体运动,明显减少了可能造成靶丸预热的金M带辐射流(1.6~4.4 keV)份额。针对黑腔内部不同区域等离子体,研究了光斑区等离子体的运动,分析了其与电子热传导限流因子的关系;研究了冕区等离子体的运动,分析了不同充气等离子体条件对其的影响;在同一发次实验中同时测量了光斑区与再发射区的辐射流比值。  相似文献   
996.
Multi-resonance thermally activated delayed fluorescence (MR-TADF) materials hold great promise for advanced high-resolution organic light-emitting diode (OLED) displays. However, persistent challenges, such as severe aggregation-caused quenching (ACQ) and slow spin-flip, hinder their optimal performance. We propose a synergetic steric-hindrance and excited-state modulation strategy for MR-TADF emitters, which is demonstrated by two blue MR-TADF emitters, IDAD-BNCz and TIDAD-BNCz , bearing sterically demanding 8,8-diphenyl-8H-indolo[3,2,1-de]acridine (IDAD) and 3,6-di-tert-butyl-8,8-diphenyl-8H-indolo[3,2,1-de]acridine (TIDAD), respectively. These rigid and bulky IDAD/TIDAD moieties, with appropriate electron-donating capabilities, not only effectively mitigate ACQ, ensuring efficient luminescence across a broad range of dopant concentrations, but also induce high-lying charge-transfer excited states that facilitate triplet-to-singlet spin-flip without causing undesired emission redshift or spectral broadening. Consequently, implementation of a high doping level of IDAD-BNCz resulted in highly efficient narrowband electroluminescence, featuring a remarkable full-width at half-maximum of 34 nm and record-setting external quantum efficiencies of 34.3 % and 31.8 % at maximum and 100 cd m−2, respectively. The combined steric and electronic effects arising from the steric-hindered donor introduction offer a compelling molecular design strategy to overcome critical challenges in MR-TADF emitters.  相似文献   
997.
关于非均质焊接接头中的J积分断裂判据   总被引:5,自引:0,他引:5  
采用平面应力弹塑性大变形有限元方法、云纹干涉法以及云纹干涉-有限元混合法,从J积分守恒性与J主导有效性两方面仔细考察了非均质焊接接头中的J积分断裂判据.结果表明,至少对于该文所研究的情形而言,J积分守恒性及J主导有效性均是有条件存在的.因此,在非均质焊接接头中直接应用J积分作为断裂判据是不合适的.  相似文献   
998.
A novel method of protein extraction from perennial Bupleurum root for 2-DE   总被引:1,自引:0,他引:1  
Xie H  Pan S  Liu S  Ye K  Huo K 《Electrophoresis》2007,28(5):871-875
The perennial Bupleurum root is thick and woody and contains high levels of interfering compounds. Common protein extraction methods have proved refractory towards the isolation of proteins suitable for 2-DE, due to the presence of interfering compounds. A novel method for extracting proteins suitable for 2-DE was established to overcome these problems. The main characteristic of this protocol is the partitioning of the proteins into the aqueous (fraction A-2), chloroform and isoamyl alcohol phases (A-3), and the interphase (A-1). The proteins are then extracted from each of these phases. From A-1, 85% (extracted protein against total proteins) proteins could be extracted and purified. For fraction A-2, a novel phenol extraction step is employed for the extraction of proteins. Based on the well-resolved 2-DE patterns, our protein preparation is free of interfering compounds. Using these methods (A-1, A-2, and A-3-3), a total of 3662 (1526 + 1128 + 1008) spots could be separated, and a protein yield of about 1.41 mg per 1.0 g fresh root material was obtained. To our knowledge, this is the first time that a protocol for protein extraction from perennial Bupleurum root has been reported that gives reproducible results. The protocol is expected to be applicable to other recalcitrant plant tissues as well.  相似文献   
999.
The local well-posedness of the Cauchy problem for the fifth order shallow water equation δtu+αδx^5u+βδx^3u+rδxu+μuδru=0,x,t∈R, is established for low regularity data in Sobolev spaces H^s(s≥-3/8) by the Fourier restriction norm method. Moreover, the global well-posedness for L^2 data follows from the local well-posedness and the conserved quantity. For data in H^s(s〉0), the global well-posedness is also proved, where the main idea is to use the generalized bilinear estimates associated with the Fourier restriction norm method to prove that the existence time of the solution only depends on the L^2 norm of initial data.  相似文献   
1000.
In the title two‐dimensional coordination polymer, [Mn(1,4‐BDOA)(4,4‐bipy)(H2O)2]n [1,4‐BDOA2− is the p‐phenyl­ene­dioxy­di­acetate dianion (C10H8O6) and 4,4‐bipy is 4,4‐bi­pyridine (C10H8N2)], each MnII atom displays octahedral coordination by two O atoms of the 1,4‐BDOA2− groups, two N atoms of the 4,4‐bipy ligands and two solvent water mol­ecules. The MnII atom, 4,4‐bipy ligand and 1,4‐BDOA2− group occupy different inversion centres. Adjacent MnII atoms are bridged by 1,4‐BDOA2− groups and 4,4‐bipy ligands, forming a two‐dimensional network with Mn⋯Mn separations of 11.592 (2) and 11.699 (2) Å. Hydro­gen bonds from a water O—H group link the layers in the third dimension.  相似文献   
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