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Lee Kookjin Elman Howard C. Powell Catherine E. Lee Dongeun 《BIT Numerical Mathematics》2022,62(3):965-994
BIT Numerical Mathematics - In uncertainty quantification, it is commonly required to solve a forward model consisting of a partial differential equation (PDE) with a spatially varying uncertain... 相似文献
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Evangelia‐Eirini N. Vlachou Catherine Gabriel Konstantinos E. Litinas 《Journal of heterocyclic chemistry》2019,56(1):99-107
Dipetalolactone and 4‐methyldipetalolactone are prepared in excellent yield by a one‐pot tandem propargylation/Claisen rearrangement/cyclization reaction of the corresponding 5,7‐dihydroxycoumarins with 3‐chloro‐3‐methylbut‐1‐yne in the presence of Cs2CO3 under microwave irradiation. The analogous reactions of propargyl chloride with esculetins or 5,7‐dihydroxycoumarins led to dipropargyloxy derivatives. The later by treatment with gold nanoparticles supported on TiO2 or BF3.Et2O in N,N‐dimethylformamide (DMF) under microwave irradiation resulted in very good to excellent yield to the corresponding fused dipyranocoumarins. The reactions of esculetins with 3‐chloro‐3‐methylbut‐1‐yne gave mainly exomethylene fused dioxino[g]coumarins. 相似文献
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Measurement of emerging dechloranes in human serum using modulated gas chromatography coupled to electron capture negative ionization time‐of‐flight mass spectrometry 下载免费PDF全文
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Dr. Martin Schmidt Prof. Albert Masson Prof. Hai‐Ping Cheng Prof. Catherine Bréchignac 《Chemphyschem》2015,16(4):855-865
Adsorption and coadsorption studies on free silver clusters show that nitrogen physisorbs like rare gases, whereas oxygen chemisorbs with similarities and differences to bulk silver surfaces. Silver nanoparticles activate, or even dissociate adsorbed oxygen molecules. The global electron configurations of the adsorbent and adsorbate dominate the stability at small clusters. This is more important than geometry and site effects. Due to electronic shell effects and electron pairing, the activation of oxygen strongly varies with size. At more than 40 free electrons in the complex, such quantum effects start to blur. The size dependence becomes smoother and general trends govern the reactivity, which is driven by the interaction between the charge state of the nanoparticle and the charge transfer of the reaction. 相似文献
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Observation of insulating–insulating monoclinic structural transition in macro‐sized VO2 single crystals [Phys. Status Solidi RRL 5, No. 3, R107–R109 (2011)] 下载免费PDF全文
Bongjin Simon Mun Kai Chen Youngchul Leem Catherine Dejoie Nobumichi Tamura Martin Kunz Zhi Liu Michael E. Grass Changwoo Park Joonseok Yoon Y. Yvette Lee Honglyoul Ju 《固体物理学:研究快报》2015,9(3):206-206
In our article, we reported the observation of monoclinic M2 to M1 structural phase transition in VO2 single crystal near the temperature of ~49 °C. However, the re‐examination of Laue patterns reveals that previously defined monoclinic M1 and M2 phases can be interpreted as monoclinic M2 and triclinic T phases instead. Careful experimental geometry calibration and further refinement of the lattice parameter ratios and angles show that monoclinic M2 and triclinic T phases fit better with the experimental data. On the other hand, our previous misidentification of the insulating phases does NOT affect the conclusions of our article. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
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Dr. Catherine Adam Dr. Lixu Yang Dr. Scott L. Cockroft 《Angewandte Chemie (International ed. in English)》2015,54(4):1164-1167
Fluorocarbons often have distinct miscibility properties compared to their nonfluorinated analogues. These differences may be attributed to van der Waals dispersion forces or solvophobic effects, but their contributions are notoriously difficult to separate in molecular recognition processes. Here, molecular torsion balances were used to compare cohesive alkyl and perfluoroalkyl interactions in a range of solvents. A simple linear regression enabled the energetic partitioning of solvophobic and van der Waals forces in the self‐association of apolar chains. The contributions of dispersion interactions in apolar cohesion were found to be strongly attenuated in solution compared to the gas phase, but still play a major role in fluorous and organic solvents. In contrast, solvophobic effects were found to be dominant in driving the association of apolar chains in aqueous solution. The results are expected to assist the computational modelling of van der Waals forces in solution. 相似文献
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Electrogenerated Chemiluminescence of Cationic Triangulene Dyes: Crucial Influence of the Core Heteroatoms 下载免费PDF全文
Dr. Catherine Adam Antoine Wallabregue Haidong Li Jérôme Gouin Dr. Rémi Vanel Stéphane Grass Dr. Johann Bosson Dr. Laurent Bouffier Prof. Jérôme Lacour Prof. Neso Sojic 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(52):19243-19249
Trianguleniums are fascinating conjugated hexacyclic cations that exhibit interesting electronic and optical properties. Herein, the electrogenerated chemiluminescence (ECL) emission of this family of fluorescent dyes is reported for the first time. Redox behavior and fluorescence properties of eight cationic triangulene luminophores with different heteroatom patterns in the core structure and various pending substituents were examined to rationalize the ECL. Clearly, the more electron‐rich the carbocation, the more efficient the corresponding ECL; two very distinct classes of triangulenes can be drawn from these studies by using an ECL wall sufficiency formalism. 相似文献