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931.
Nano-carbon connections among carbon-coated LiFe0.8Mn0.2PO4 grains are successfully constructed using polyacrylic acid and sucrose as carbon sources by sol-gel method, which can improve the electrochemical performance of LiFe0.8Mn0.2PO4. Samples were characterised by X-ray diffraction, scanning electron microscopy and electrochemical tests. The electrochemical tests show LiFe0.8Mn0.2PO4 grains connected by nano-carbon networks obtain the discharge specific capacity of 165 mA h g?1 at 0.1 C rate and excellent rate capability. Its specific capacity reaches 122 mA h g?1 at 5 C rate. Its capacity retention at 5 C rate attains 97% cycled 100 cycles. Therefore the construction of nano-carbon networks offers an effective and convenient technique to improve the specific capacities and rate capabilities of electrode materials of low electronic conductivity. 相似文献
932.
Ting Wu Yi Ping Du Dong Jiang Bo Hao Yu 《International Journal of Polymer Analysis and Characterization》2014,19(5):441-452
The aim of this work is to discriminate thermoplastic polyester-polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polytrimethylene terephthalate (PTT), which cannot be easily identified by many methods. Both matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) were applied to identify these polyesters owing to their analytical ability to determining polymers' chemical structure. The three thermoplastic polyesters can be easily distinguished by MALDI-TOF MS according to their different repeated units. Py-GC/MS was used to analyze their specific pyrolyzates. The three polyesters can be identified through their characteristic pyrolysis products as well. 相似文献
933.
Thermal behaviors of typical weak basic ion exchange resins (301 and 315) were studied with thermogravimetry, elemental analysis, and Fourier transform infrared spectrometer in this study. Results indicated that there were three stages for 301 resin mass loss, the first stage and the second stage were mainly related to the decomposition of functional group, and the third stage was the decomposition of main chain. Whereas there were two stages for 315 resin mass loss, the first stage was elimination of moisture, and the second stage was the decompositions of functional group and main chain. Moreover, the decomposition of tertiary amine had three stages, the polyamine was a continuous mass loss process, and the thermostability of tertiary amine was weaker than that of polyamine. 相似文献
934.
Haojie Gao Yuezhao Zhu Feng Fu Hao Wu Yang DU Haijun Chen Chuanhua Liao Hongtu Fan 《Journal of Thermal Analysis and Calorimetry》2014,117(2):973-978
An in situ pyrolysis process of high moisture content lignite in an autogenerated steam agent was proposed. The aim is to utilize steam autogenerated from lignite moisture as a reactant to produce fuel gas and additional hydrogen. Thermogravimetric analysis revealed that mass loss and maximum mass loss rate increased with the rise of heating rates. The in situ pyrolysis process was performed in a screw kiln reactor to investigate the effects of moisture content and reactor temperature on product yields, gas compositions, and pyrolysis performance. The results demonstrated that inherent moisture in lignite had a significant influence on the product yield. The pyrolysis of L R (raw lignite with a moisture content of 36.9 %, wet basis) at 900 °C exhibited higher dry yield of 33.67 mL g?1 and H2 content of 50.3 vol% than those from the pyrolysis of the predried lignite. It was also shown that increasing reaction temperature led to a rising dry gas yield and H2 yield. The pyrolysis of L R showed the maximum dry yield of 33.7 mL g?1 and H2 content of 53.2 vol% at 1,000 °C. The LHV of fuel gas ranged from 18.45 to 14.38 MJ Nm?3 when the reactor temperature increased from 600 to 1,000 °C. 相似文献
935.
Shasha Song Haiqiao Wang Prof. Dr. Aixin Song Prof. Dr. Shuli Dong Prof. Dr. Jingcheng Hao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):9063-9072
The aggregation behavior of mixtures of the alkaline amino acid L ‐Arginine (L ‐Arg) and bis(2‐ethylhexyl)phosphoric acid (DEHPA) in water was studied in detail. At a fixed L ‐Arg concentration, a phase sequence of micellar phase (L1 phase), vesicle phase (Lαv phase), planar lamellar phase (Lαl phase), and sponge phase (L3 phase) was obtained with increasing DEHPA concentration due to changes in the packing parameter. The phase transition of the lamellar structures was determined by freeze‐fracture TEM and 2H NMR spectroscopy. Rheological measurements reflected the phase transition through significant variations of both the elastic modulus and the viscous modulus. Porous CeO2 materials were produced by utilizing the L3 phase as template, and the porous CeO2 exhibited excellent catalytic oxidation activity toward CO due to its high surface area, which provides more active sites for CO conversion. 相似文献
936.
Back Cover: Two‐Dimensional Tetrathiafulvalene Covalent Organic Frameworks: Towards Latticed Conductive Organic Salts (Chem. Eur. J. 45/2014) 下载免费PDF全文
937.
Shan She Shengtai Bian Prof. Dr. Jian Hao Dr. Jiangwei Zhang Jin Zhang Prof. Dr. Yongge Wei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(51):16987-16994
A series of aliphatic organoimido derivatives of hexamolybdate based on amantadine, namely (nBu4N)2[Mo6O18(?NC10H15)] ( 1 ), (nBu4N)2 {cis‐[Mo6O17(?NC10H15)2]} ( 2 ), (nBu4N)2{trans‐[Mo6O17(?NC10H15)2]} ( 3 ), and (nBu4N)2[Mo6O16(?NC10H15)3] ( 4 ), was synthesized in reasonable yield by dehydration with N,N′‐dicyclohexylcarbodiimide (DCC). They were characterized by IR and UV/Vis spectroscopy, elemental analysis, ESI mass spectrometry, and single‐crystal X‐ray structure analysis. The spectral and structural similarities and differences between monosubstituted, cis‐disubstituted, and trans‐disubstituted organoimido derivatives were elucidated and may provide guidance for related work on organoimido‐functionalized Lindqvist‐type polyoxometalates. In addition, trans‐disubstituted and polysubstituted derivatives containing aliphatic organoimido ligands have not yet been reported, and the crystal structure of the trans isomer may lead us to a deeper understanding of disubstituted derivatives. Furthermore, proliferation and morphology of MCF‐7 cells were studied with compound 1 . The present results show that the DCC‐dehydrating protocol could be an efficient approach to covalently graft bioactive ligands such as amantadine onto POMs and enhance their application in clinical cancer treatment. 相似文献
938.
Photochemically Engineering the Metal–Semiconductor Interface for Room‐Temperature Transfer Hydrogenation of Nitroarenes with Formic Acid 下载免费PDF全文
Dr. Xin‐Hao Li Yi‐Yu Cai Ling‐Hong Gong Dr. Wei Fu Dr. Kai‐Xue Wang Dr. Hong‐Liang Bao Dr. Xiao Wei Dr. Jie‐Sheng Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(50):16732-16737
A mild photochemical approach was applied to construct highly coupled metal–semiconductor dyads, which were found to efficiently facilitate the hydrogenation of nitrobenzene. Aniline was produced in excellent yield (>99 %, TOF: 1183) using formic acid as hydrogen source and water as solvent at room temperature. This general and green catalytic process is applicable to a wide range of nitroarenes without the involvement of high‐pressure gases or sacrificial additives. 相似文献
939.
Palladium‐Catalyzed One‐Pot Three‐ or Four‐Component Coupling of Aryl Iodides,Alkynes, and Amines through CN Bond Cleavage: Efficient Synthesis of Indole Derivatives 下载免费PDF全文
Wei Hao Weizhi Geng Prof. Dr. Wen‐Xiong Zhang Prof. Dr. Zhenfeng Xi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(9):2605-2612
An efficient synthesis of N‐substituted indole derivatives was realized by combining the Pd‐catalyzed one‐pot multicomponent coupling approach with cleavage of the C(sp3)?N bonds. Three or four components of aryl iodides, alkynes, and amines were involved in this coupling process. The cyclopentadiene–phosphine ligand showed high efficiency. A variety of aryl iodides, including cyclic and acyclic tertiary amino aryl iodides, and substituted 1‐bromo‐2‐iodobenzene derivatives could be used. Both symmetric and unsymmetric alkynes substituted with alkyl, aryl, or trimethylsilyl groups could be applied. Cyclic secondary amines such as piperidine, morpholine, 4‐methylpiperidine, 1‐methylpiperazine, 2‐methylpiperidine, and acyclic amines including secondary and primary amines all showed good reactivity. Further application of the resulting indole derivatives was demonstrated by the synthesis of benzosilolo[2,3‐b]indole. 相似文献
940.
Phosphine‐Catalyzed [3+2] Cycloaddition Reactions of Azomethine Imines with Electron‐Deficient Alkenes: A Facile Access to Dinitrogen‐Fused Heterocycles 下载免费PDF全文
Zhen Li Hao Yu Honglei Liu Lei Zhang Hui Jiang Bo Wang Prof. Dr. Hongchao Guo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(6):1731-1736
An efficient method for the phosphine‐catalyzed [3+2] cycloaddition reaction of azomethine imines with diphenylsulfonyl alkenes to give dinitrogen‐fused bi‐ or tricyclic heterocyclic compounds in high yields has been described. Moreover, two phenylsulfonyl groups installed on the heterocyclic products could be conveniently removed or transformed to other functional groups, making the reaction more useful. 相似文献