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Han Jing Sun Youhong Guo Wei Deng Sunhua Hou Chuanbin Qu Lili Li Qiang 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2287-2296
Journal of Thermal Analysis and Calorimetry - In this study, the non-isothermal pyrolysis method was used to investigate the pyrolysis characteristics of oil shale from four areas: namely Nongan,... 相似文献
955.
The N–N bond is present in many important organic compounds, such as hydrazines, pyrazoles, azos, etc. Many methods based on transition metal catalyzed N–N coupling or functionalization of hydrazine have been reported for the synthesis of N–N containing organic compounds. In recent years, electrochemical dehydrogenative N–H/N–H coupling has become a powerful tool for the construction of N–N bearing organic compounds. The electrochemical methods employ electrons as traceless redox reagents instead of chemicals and produce hydrogen as the only byproduct. In this review, we summarize the recent advances in the electrochemical dehydrogenative N–H/N–H coupling reactions with focus on the mechanistic insights and synthetic applications of these transformations. 相似文献
956.
Guanfeng Lin Tiancai Liu Jingyuan Hou Zhiqi Ren Jianwei Zhou Qianni Liang Zhenhua Chen Wenqi Dong Yingsong Wu 《Journal of fluorescence》2015,25(2):361-367
A sensitive, rapid and novel measurement method for cytokeratin 19 fragment (CYFRA 21–1) in human serum by magnetic particle-based time-resolved fluoroimmunoassay (TRFIA) is described. Built on a sandwich-type immunoassay format, analytes in samples were captured by one monoclonal antibody coating onto the surface of magnetic beads and “sandwiched” by another monoclonal antibody labeled with europium chelates. The coefficient variations of the method were lower than 7 %, and the recoveries were in the range of 90–110 % for serum samples. The lower limit of quantitation of the present method for CYFRA 21–1 was 0.78 ng/ml. The correlation coefficient of CYFRA 21–1 values obtained by our novel TRFIA and CLIA was 0.980. The present novel TRFIA demonstrated high sensitivity, wider effective detection range and excellent reproducibility for determination of CYFRA 21–1 can be useful for early screening and prognosis evaluation of patients with non-small cell lung cancer. 相似文献
957.
Journal of Structural Chemistry - The self-assembly reaction of the bis-Schiff base N,N′-bis(4-Bromosalicylidene)-1,3-pentanediamine (H2L) with nickel chloride and sodium azide in methanol... 相似文献
958.
Khaled Tawfik Alali Dr. Jingyuan Liu Dr. Rongrong Chen Dr. Qi Liu Dr. Hongsen Zhang Jundong Li Jindi Hou Prof. Rumin Li Prof. Jun Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(51):11892-11902
Semiconductor metal oxides (SMO)-based gas-sensing materials suffer from insufficient detection of a specific target gas. Reliable selectivity, high sensitivity, and rapid response–recovery times under various working conditions are the main requirements for optimal gas sensors. Chemical warfare agents (CWA) such as sarin are fatal inhibitors of acetylcholinesterase in the nerve system. So, sensing materials with high sensitivity and selectivity toward CWA are urgently needed. Herein, micro-nano octahedral Co3O4 functionalized with hexafluoroisopropanol (HFIP) were deposited on a layer of reduced graphene oxide (rGO) as a double-layer sensing materials. The Co3O4 micro-nano octahedra were synthesized by direct growth from electrospun fiber templates calcined in ambient air. The double-layer rGO/Co3O4-HFIP sensing materials presented high selectivity toward DMMP (sarin agent simulant, dimethyl methyl phosphonate) versus rGO/Co3O4 and Co3O4 sensors after the exposure to various gases owing to hydrogen bonding between the DMMP molecules and Co3O4-HFIP. The rGO/Co3O4-HFIP sensors showed high stability with a response signal around 11.8 toward 0.5 ppm DMMP at 125 °C, and more than 75 % of the initial response was maintained under a saturated humid environment (85 % relative humidity). These results prove that these double-layer inorganic–organic composite sensing materials are excellent candidates to serve as optimal gas-sensing materials. 相似文献
959.
Zhengluo Wang Zhiwei Zhao Yanru Zhang Dr. Xiaopeng Yang Xuan Sun Dr. Jinyang Zhang Prof. Linrui Hou Prof. Changzhou Yuan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(3):863-873
The exploration of anode materials with a high degree of electrochemical utilization for Li-ion batteries (LIBs) still remains a huge challenge despite pioneering breakthroughs. Rational engineering of electrode structures/components by facile strategies would offer infinite possibilities for the development of LIBs. In this study, one-dimensional ultralong nanohybrids of ultrafine NiCoO2 nanoparticles dispersed in situ in and/or on the surface of amorphous N-doped carbon nanofibers (NCO@ANCNFs) were fabricated by a bottom-up electrospinning protocol. By virtue of synergistic structural/component features, the obtained ultralong NCO@ANCNFs with low NCO loading (≈33.6 wt %) show highly efficient Li+ storage performance with high reversible capacity, high rate capability, and long cycle life. The unusual reversible crystalline transformation during cycling was analyzed. Quantitative analysis revealed that the pseudocapacitive contribution mainly accounts for the superior lithium storage of the NCO@ANCNFs. Besides, the ability of the hybrid anode to deliver competitive Li-storage properties even without conductive carbon greatly enhances its commercial applicability. An NCO@ANCNFs//LiNi0.8Co0.15Al0.05O2 full battery was assembled and exhibited striking electrochemical properties. This contribution offers a scalable methodology to fabricate highly efficient hybrid anodes for advanced next-generation LIBs. 相似文献
960.
Tianyu Shan Liang Gao Xiaoqian Tong Qinqing Du Zhihang An Huiwen He Prof. Jiaping Lin Prof. Si Chen Prof. Xu Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(52):12098-12104
An amazing phenomenon of the relative magnitude of modulus of two liquid-crystal (LC) gels is found inverted under/above their phase transition temperature TLC-iso, which is further proved to be caused by their diverse morphology flexibility. By testing the polarity of two LCs, gelator POSS-G1-Boc (POSS=polyhedral oligomeric silsesquioxane) was discovered to self-assemble into more flexible structures in a relatively low polar LC, whereas more rigid ones are formed in higher polar LC. Hence, a fitting function to connect morphology flexibility with solvent polarity was established, which can even be generalized to a number of common solvents. Experimental observations and coarse-grained molecular dynamics simulations revealed that solvent polarity mirrors a “Morse code”, with each “code” corresponding to a specific morphology flexibility. 相似文献