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81.
Chunyuan Li Weijiang Ding Zhigang She Yongcheng Lin 《Chemistry of Natural Compounds》2008,44(2):163-165
A new biphenyl derivative 3,5′-dihydroxy-4′,5-dimethoxy-2′-methyl-[1,1′-biphenyl]-2-carboxylic acid methyl ester (1), was isolated from the culture broth of a fungus isolated from the rhizosphere soil of mangrove root on the South China
Sea. The structure of 1 was determined by comprehensive spectroscopic methods, primarily 2D NMR techniques.
Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 128–129, March–April, 2008. 相似文献
82.
Shan She Weimin Xuan Nicola L. Bell Robert Pow Eduard Garrido Ribo Zoe Sinclair De-Liang Long Leroy Cronin 《Chemical science》2021,12(7):2427
The precise control over the formation of complex nanostructures, e.g. polyoxometalates (POMs), at the sub-nanoscale is challenging but critical if non-covalent architectures are to be designed. Combining biologically-evolved systems with inorganic nanostructures could lead to sequence-mediated assembly. Herein, we exploit oligopeptides as multidentate structure-directing ligands via metal-coordination and hydrogen bonded interactions to modulate the self-assembly of POM superstructures. Six oligopeptides (GH, AH, SH, G2H, G4H and G5H) are incorporated into the cavities of Molybdenum Blue (MB) POM nanowheels. It is found that the helicity of the nanowheel can be readily switched (Δ to Λ) by simply altering the N-terminal amino acid on the peptide chain rather than their overall stereochemistry. We also reveal a delicate balance between the Mo-coordination and the hydrogen bonds found within the internal cavity of the inorganic nanowheels which results in the sequence mediated formation of two unprecedented asymmetrical nanowheel frameworks: {Mo122Ce5} and {Mo126Ce4}.Peptide sequence can be used to control the self-assembly and structures of nanoscale molybdenum blue polyoxometalate (POM) wheel-shaped clusters. 相似文献
83.
Nickel and potassium co-medified β-Mo2C catalysts were prepared and used for CO hydrogenation reaction. The major products over β-Mo2C were C1-C4 hydrocarbons, only few alcohols were obtained. Addition of potassium resulted in remarkable selectivity shift from hydrocarbons to alcohols at the expense of CO conversion over β-Mo2C. Moreover, it was found that potassium enhanced the ability of chain propagation with a higher C2+OH production. Modified by nickel, β-Mo-2C showed a relatively high CO conversion, however, the products were similar to those of pure β-Mo2C. When co-modified by nickel and potassium,β-Mo2C exhibited high activity and selectivity towards mixed alcohols synthesis, and also the whole chain propagation to produce alcohols especially for the stage of C1OH to C2OH was remarkably enhanced. It was concluded that the Ni and K had, to some extent, synergistic effect on CO conversion. 相似文献
84.
Changlun Shao Changyun Wang Meiyan Wei Zhenbin Jia Zhigang She Yongcheng Lin 《Chemistry of Natural Compounds》2009,45(6):779-781
Two new benzaldehyde derivatives, 6-ethyl-2-hydroxy-4-methoxy-3-methylbenzaldehyde (1), 6-ethyl-2,4-dihydroxy-3-methylbenzaldehyde (2), together with 2, 4-dihydroxy-3,6-dimethylbenzaldehyde (3) were isolated from mangrove fungus (No. ZZF 32#) from the South China Sea. The structures of compounds 1 and 2 were established by comprehensive analysis of the spectral data, especially 2D NMR spectral results. 相似文献
85.
Fan Liu Qing Li Hong Yang Xiao‐Ling Cai Xue‐Kui Xia Sheng‐Ping Chen Meng‐Feng Li Zhi‐Gang She Yong‐Cheng Lin 《Magnetic resonance in chemistry : MRC》2009,47(5):453-455
Two new natural products, tenelate A ( 1 ) and B ( 2 ), together with the known compound, tenellic acid C ( 3 ), were isolated from the mangrove endophytic fungus Talaromyces sp. (SBE‐14), from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR techniques. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
86.
XPS study of potassium-promoted molybdenum carbides for mixed alcohols synthesis via CO hydrogenation 下载免费PDF全文
The X-ray photoelectron spectroscopy (XPS) was used to investigate the surface characteristic of potassium-promoted or un-promoted both β-Mo_2C and α-MoC_(1-x) pretreated by syngas at different temperatures, and the promotional effect of potassium on the catalytic performance was also studied. XPS results revealed that the content of surface Mo and its valence distribution between β-Mo_2C and α-MoC_(1-x) were quite different. Promoted by potassium, the remarkable changes were observed for surface composition and valence of Mo distribution over β-Mo_2C. Potassium had strong electronic effect on β-Mo_2C, which led to a higher Mo~(4+) content. On the contrary, potassium had little electronic effect on α-MoC_(1-x), and K-Mo interaction was weak. Therefore, Mo~0 and Mo~(2+) became the dominant species on the catalyst surface, and the Mo~(4+) content showed almost no increase as the pretreatment temperature enhanced. In terms of catalytic performance of molybdenum carbides, the increase in Mo~0 most likely explained the increase in hydrocarbon selectivity, yet Mo~(4+) might be responsible for the alcohols synthesis. 相似文献
87.
Lu Wen Zhiyong Guo Qing Li Dezhi Zhang Zhigang She L. L. P. Vrijmoed 《Chemistry of Natural Compounds》2010,46(3):363-365
A new griseofulvin derivative, 7-chloro-2',5,6-trimethoxy-6'-methylspiro(benzofuran-2(3H),1'-(2) cyclohexene)3,4'-dione (1),
together with the known 2-acetyl-7-methoxybenzofuran (2), was isolated from the marine-derived mangrove endophytic fungus
Sporothrix sp. (No. 4335). The structure of new compound 1 was elucidated by analysis of spectroscopic data. 相似文献
88.
CAO Mengyao SUN Yueyang XIAO Mingshu LI Li LIU Xiaohui JIN Hong PEI Hao 《高等学校化学研究》2020,36(2):254-260
In spite of great development in nanoparticle-based drug delivery systems(DDSs)for improved therapeutic efficacy,it remains challenging for effective delivery of chemotherapeutic drugs to targeted tumor cells.In this work,we report a triangle DNA origami as targeted DDS for cancer therapy.DNA origami shows excellent biocompatibility and stability in cell culture medium for 24 h.In addition,the DNA origami structures conjugated with multivalent aptamers enable for efficient delivery of anticancer drug doxorubicin(Dox)into targeted cancer cell due to their targeting function,reducing side effects associated with nonspecific distribution.Moreover,we also demonstrated that the multivalent aptamer-modified DNA origami loading Dox exhibits prominent therapeutic efficacy in vitro.Accordingly,this work provides a good paradigm for the development of DNA origami nanostructure-based targeted DDS for cancer therapy. 相似文献
89.
综述国内外塑化剂迁移量测定和迁移模型研究进展,从创新实验测定方法和实验误差分析的角度简要评述了迁移量测定的研究成果;从数学模型的角度对微分方程模型、统计模型和计算机模拟3类重要迁移模型进行评述。最后指出,测定实验和迁移模型相结合来研究塑化剂迁移问题是未来一个值得重视的方法。 相似文献
90.