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排序方式: 共有390条查询结果,搜索用时 31 毫秒
131.
Hagiwara K Sei Y Akita M Yoshizawa M 《Chemical communications (Cambridge, England)》2012,48(62):7678-7680
A novel tubular macrocycle containing four anthracene panels covalently linked by meta-phenylene spacers was synthesized. The tube is approximately 1 nm long with anthracene panels delimiting a columnar cavity with a diameter of ~1 nm and exhibits strong blue fluorescence. 相似文献
132.
J. W. Hwang Y. Satou T. Nakamura Y. Kondo N. Matsui Y. Hashimoto T. Nakabayashi T. Okumura M. Shinohara N. Fukuda T. Sugimoto H. Otsu Y. Togano T. Motobayashi H. Sakurai Y. Yanagisawa N. Aoi S. Takeuchi T. Gomi M. Ishihara S. Kawai H. J. Ong T. K. Onishi S. Shimoura M. Tamaki T. Kobayashi Y. Matsuda N. Endo M. Kitayama 《Few-Body Systems》2013,54(7-10):1469-1472
The 16C nucleus has been investigated by the neutron knockout reaction of 17C on a liquid hydrogen target. Applying the invariant mass method in inverse kinematics and γ-ray spectroscopy, the energy spectrum was reconstructed by triple-coincidence measurement, in which neutrons, charged fragments, and γ rays from the decay of the reaction residue (16C*) were detected. A peak at 0.47 MeV was observed in the invariant mass spectrum in coincidence with a peak at 0.74 MeV in the γ-ray spectrum, which indicates the presence of an unbound state with an excitation energy of 5.46 MeV. Comparison of the experimental cross section with the value derived by a theoretical calculation provided evidence that the spin-parity of this state is 2?. 相似文献
133.
The study of chemisorption of gases on catalyst surfaces is of primary importance in elucidating the mechanism of heterogeneous catalysis. Accordingly, the adsorption of each of the gases which participate in the catalysis has been studied separately in many cases. However, chemisorption on the catalyst surface during the progress of reaction, generally speaking, cannot be estimated from the adsorption equilibrium of reactants and products measured separately for each species, but depends upon the mechanism of the reaction, the interaction among the adsorbed species, the formation of reaction intermediates or surface complexes, and the area of active region on the surface. 相似文献
134.
Kate J. Norris Vernon K. Wong Takehiro Onishi Andrew J. Lohn Elane Coleman Gary S. Tompa Nobuhiko P. Kobayashi 《Surface science》2012,606(19-20):1556-1559
We discuss an ex-situ monitoring technique based on glancing-angle infrared-absorption used to determine small amounts of erbium antimonide (ErSb) deposited on an indium antimonide (InSb) layer epitaxially grown on an InSb (100) substrate by low pressure metal organic chemical vapor deposition (MOCVD). Infrared absorption from the indium–hydrogen (InH) stretching mode at 1754.5 cm? 1 associated with a top most surface of an epitaxial InSb layer was used to compare varying levels of surface coverage with ErSb. Among four samples of varying coverage of ErSb deposition (7.2 to 21.5 monolayers), detected infrared absorption peaks distinct to InH weakened as ErSb surface coverage increased. In the early stage of ErSb deposition, our study suggests that outermost indium atoms in the InSb buffer layer are replaced by Er resulting in increase in absorption associated with the InH mode. Using this simple ex-situ technique, we show that it is possible to calibrate the amount of ErSb deposited atop each individual InSb substrate for depositions of few to tens of monolayers. 相似文献
135.
The subnanometer topography of a partially crystalline polyethylene film was observed in liquid n-dodecane using a frequency-modulation atomic force microscope. Locally ordered structures were found and assigned to a (100) facet of crystalline domains. 相似文献
136.
137.
Kyosuke Matsumoto Shunsuke Kusaba Yuya Tanaka Yoshihisa Sei Munetaka Akita Kazushi Aritani Masa‐aki Haga Michito Yoshizawa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(25):8551-8555
Synthesis of molecular containers capable of incorporating multiple fullerenes remains challenging. Reported here is that room‐temperature mixing of metal ions with W‐shaped bispyridine ligands featuring polyaromatic panels results in the quantitative formation of a peanut‐shaped M2L4 capsule. The capsule reversibly converts into two molecules of an ML2 double tube in response to changes in the solvent. Notably, the capsule allows the incorporation of two fullerene molecules into the connected two spherical cavities at room temperature. The close proximity yet non‐contact of the encapsulated C60 molecules, with a separation of 6.4 Å, was revealed by X‐ray crystallographic analysis. The resultant, unusual fullerene dimer undergoes sequential reduction within the capsule to generate (C60.?)2, C60.??C602?, and (C602?)2 species. Furthermore, temperature‐controlled stepwise incorporation of two C60 molecules into the capsule is demonstrated. 相似文献
138.
Y. Ichikawa T. Kubo N. Aoi V. Banerjee A. Chakrabarti N. Fukuda H. Iwasaki S. Kubono T. Motobayashi T. Nakabayashi T. Nakamura T. Nakao T. Okumura H. J. Ong T. K. Onishi D. Suzuki H. Suzuki M. K. Suzuki T. Teranishi K. N. Yamada H. Yamaguchi H. Sakurai 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):375-378
$ \beta$ -decay spectroscopy on a T z = - 2 proton-rich nucleus 24Si was performed. The decay scheme of 24Si was reconstructed by the $ \beta$ -delayed $ \gamma$ -ray and proton measurements. Two $ \beta$ branches to the bound 11 + and 12 + states in 24Al were observed for the first time. The observation of the allowed transition firmly established the spin-parity assignment for the 12 + states. The branching ratios to the 11 + and 12 + states were determined to be 31(4)% and 23.9(15)%, respectively. The branching ratios to three unbound states in 24Al including a new level at 6.735MeV were also determined for the first time. The level structure of 24Al was compared with its mirror nucleus 24Na . The Thomas-Ehrman shift on the 12 + state indicates s -wave dominance in the state as well as a characteristic behavior of the weakly bound s -wave proton in 24Al . 相似文献
139.
A persistent photoinduced metal-to-insulator transition has been confirmed in a manganite thin film, Pr_(0.55)(Ca_(0.75)Sr_(0.25))_(0.45)MnO3, near a multicritical point by monitoring with transport measurements and x-ray photoemission spectroscopy. Together with the previously reported reverse effect, the photoinduced insulator-to-metal transition, it is found that the relative stability of the metallic and insulating phases interchanges around 80 K in the middle of a very wide hysteresis loop, which is a manifestation of the large potential barrier due to the long-range elastic energy. It is shown that photons are much more effective in overcoming the barrier via the electronically excited intermediate states than via the heat mode. 相似文献