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11.
Numerical Investigation on 1,3-Butadiene/Propyne Co-pyrolysis and Insight into Synergistic Effect on Aromatic Hydrocarbon Formation 下载免费PDF全文
Tian-yu Li Jia-biao Zou Yan Zhang Chuang-chuang Cao Wei Li Wen-hao Yuan 《化学物理学报(中文版)》2017,30(3):287-294
A numerical investigation on the co-pyrolysis of 1,3-butadiene and propyne is performed to explore the synergistic effect between fuel components on aromatic hydrocarbon formation.A detailed kinetic model of 1,3-butadiene/propyne co-pyrolysis with the sub-mechanism of aromatic hydrocarbon formation is developed and validated on previous 1,3-butadiene and propyne pyrolysis experiments.The model is able to reproduce both the single component pyrolysis and the co-pyrolysis experiments,as well as the synergistic effect between 1,3-butadiene and propyne on the formation of a series of aromatic hydrocarbons.Based on the rate of production and sensitivity analyses,key reaction pathways in the fuel decomposition and aromatic hydrocarbon formation processes are revealed and insight into the synergistic effect on aromatic hydrocarbon formation is also achieved.The synergistic effect results from the interaction between 1,3-butadiene and propyne.The easily happened chain initiation in the 1,3-butadiene decomposition provides an abundant radical pool for propyne to undergo the H-atom abstraction and produce propargyl radical which plays key roles in the formation of aromatic hydrocarbons.Besides,the 1,3-butadiene/propyne co-pyrolysis includes high concentration levels of C3 and C4 precursors simultaneously,which stimulates the formation of key aromatic hydrocarbons such as toluene and naphthalene. 相似文献
12.
Dr. Zhao Gao Lulu Shi Fei Yan Yifei Han Wei Yuan Prof. Wei Tian 《Angewandte Chemie (International ed. in English)》2023,62(21):e202302274
Two-dimensional (2D) organic polymers have recently received considerable interest, especially those whose architectures are held together via supramolecular engineering. However, current approaches toward supramolecular 2D structures usually suffer from mutual interference of noncovalent interactions and lack of intrinsic functions. Herein, we report well-regulated 2D supramolecular polymers (2DSPs) through an aromatics-selective recognition strategy of cation-π and donor-acceptor (D-A) motifs, which are derived from C4-symmetric cationic monomers and electron-withdrawing molecules. By subtly designing the strength and direction of noncovalent driving forces, the mutual interference between cation-π and D-A interactions is effectively avoided, enabling the construction of 2DSPs in aqueous solution. On this basis, the resultant 2DSPs possess boosted photocatalytic hydrogen evolution activity at a rate of 600 μmol g−1 h−1, which is mainly ascribed to the specific stacking mode of cation-π/D-A motifs and the ordered 2D structures. 相似文献
13.
Prof. Yoann Olivier Prof. Juan-Carlos Sancho-García 《Angewandte Chemie (International ed. in English)》2023,62(38):e202305501
New heterocyclic diradicaloids based on boron and nitrogen-doped polycyclic systems with open-shell ground-states are obtained via concomitant structural and quinoidal extensions, thus allowing to merge the best of both design strategies. A combination of experimental characterization and theoretical calculations have helped disclose their electronic structure, as well as rationalize their associated magnetic and photophysical properties, spanning the chemical space of available molecular templates for cutting-edge applications in organic electronics and spintronics. 相似文献
14.
Jannik Reimler Xiao-Ye Yu Nico Spreckelmeyer Constantin G. Daniliuc Armido Studer 《Angewandte Chemie (International ed. in English)》2023,62(27):e202303222
The Friedel–Crafts acylation reaction, which belongs to the class of electrophilic aromatic substitutions is a highly valuable and versatile reaction in synthesis. Regioselectivity is predictable and determined by electronic as well as steric factors of the (hetero)arene substrate. Herein, a radical approach for the acylation of arenes and heteroarenes is presented. C−H acylation is achieved through mild cooperative photoredox/NHC radical catalysis with the cross-coupling of an arene radical cation with an NHC-bound ketyl radical as a key step. As compared to the classical Friedel–Crafts acylation, a regiodivergent outcome is observed upon switching from the ionic to the radical mode. In these divergent reactions, aroyl fluorides act as the acylation reagents in both the ionic as well as the radical process. 相似文献
15.
Keigo E. Yamada Dr. Iain A. Stepek Dr. Wataru Matsuoka Prof. Dr. Hideto Ito Prof. Dr. Kenichiro Itami 《Angewandte Chemie (International ed. in English)》2023,62(51):e202311770
Nanocarbons incorporating non-hexagonal aromatic rings - such as five-, seven-, and eight-membered rings - have various intriguing physical properties such as curved structures, unique one-dimensional packing, and promising magnetic, optical, and conductivity properties. Herein, we report an efficient synthetic approach to polycyclic aromatics containing seven-membered rings via a palladium-catalyzed intramolecular Ar−H/Ar−Br coupling. In addition to all-hydrocarbon scaffolds, heteroatom-embedded heptagon-containing polyarenes can be efficiently constructed with this method. Rhodium- and palladium-catalyzed sequential six- and seven-membered ring formations also afford complex heptagon-containing molecular nanocarbons from readily available arylacetylenes and biphenyl boronic acids. Detailed mechanistic analysis by DFT calculations showed the feasibility of seven-membered ring formation by a concerted metalation-deprotonation mechanism. This reaction can serve as a template for the synthesis of a wide range of seven-membered ring-containing molecular nanocarbons. 相似文献
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Xiaokang Li Jianqiao Li Chunyu Ma Siqi Zhang Bin Tu Wubiao Duan Qingdao Zeng 《中国化学快报》2021,32(3):1077-1080
Here,the selective adsorption behaviors of guest molecule COR in two hexamer host grids were investigated by means of scanning tunnelling microscope(STM).The assembled structures of small functional organic molecules TTBTA and TATBA were thermodynamically stable.Interestingly,the introduction of the guest molecule COR destroyed the original hexamer structure of TTBTA and combined with it to form a new triangular host-guest system.Different from TTBTA,the introduction of the guest molecule COR did not affect the six-membered ring structure of TATBA.Furthermore,the co-assembly structure of TTBTA/TATBA/COR was established and the guest molecule COR showed preferential adsorption to the TATBA host grid.Density functional theory(DFT) calculations had been performed to disclose the mechanism of the involved assemblies. 相似文献
19.
《印度化学会志》2021,98(3):100027
The convenient route for the synthesis of a series of new Isoindoline-1, 3-dione/phthalimide analogues by condensation of substituted phthalic anhydride with an appropriate Ar-amine is described. Selective phthalimide derivatives were evaluated for their preliminary biological activities against Gram-positive, Gram-negative and fungi strains. These encouraging results could be helpful for the development of new antibacterial or antifungal agents. 相似文献
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