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121.
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123.
Hiroharu Suzuki Hidehiko Yashima Toshiyuki Hirose Mitsuru Takahashi Yoshihiko Moro-Oka Tsuneo Ikawa 《Tetrahedron letters》1980,21(51):4927-4930
Trans-tetrahydrofuran-3-carbaldehydes are prepared by ruthenium-catalyzed isomerization of 4,7-dihydro-1,3-dioxepines and subsequent Lewis acid-catalyzed 1,3-alkyl migration. 相似文献
124.
Unicity theorems for entire functions 总被引:8,自引:0,他引:8
Mitsuru Ozawa 《Journal d'Analyse Mathématique》1976,30(1):411-420
125.
126.
Yamashita F Itoh T Hara H Hashida M 《Journal of chemical information and modeling》2006,46(3):1054-1059
It is a difficult task to recognize the trends in molecular physical properties relevant to a specific chemical class and find a way to optimize potential compounds. We present here a novel hierarchical data visualization technique, named "HeiankyoView", to visualize large-scale multidimensional chemical information. HeiankyoView represents hierarchically organized data objects by mapping leaf nodes as colored square icons and nonleaf nodes as rectangular borders. In this way, data objects can be expressed as equishaped icons without overlapping one another in the two-dimensional display space. HeiankyoView has been applied to visualize aqueous solubility data for 908 compounds collected from the published literature. When the results of a recursive partitioning analysis and hierarchical clustering analysis were visualized, the trends hidden in the solubility data could be effectively displayed as intuitively understandable visual images. Most interestingly, the data visualization technique, without any statistical computations, was able to assist us in extracting from such large-scale data meaningful information establishing that ClogP and the molecular weight are critical factors in determining aqueous solubility. Thus, HeiankyoView is a powerful tool to help us understand structure-activity relationships intuitively from a large-scale data set. 相似文献
127.
Shoji M Kato E Nakamura Y Fujii T Manabe Y Ueda M 《Chemical record (New York, N.Y.)》2006,6(6):344-355
The chemical aspects of the circadian leaf movement known as "nyctinasty" are discussed in this paper. Each of the nyctinastic plants of five different genera so far examined contained a pair of factors, one of which induced leaf closure and another induced leaf opening. The relative contents of the closing and opening factors changed correlating with the nyctinastic leaf movement. The use of fluorescence-labeled and photoaffinity-labeled factors revealed that the factors bind to specific cells, the motor cells, present in the pulvini, and that the membrane fraction of the motor cells contained two proteins of 210 and 180 kDa, which can bind to the factors. 相似文献
128.
Kamisetty NK Pack SP Nonogawa M Devarayapalli KC Kodaki T Makino K 《Analytical and bioanalytical chemistry》2006,386(6):1649-1655
Aminosilane-treated molecular layers on glass surfaces are frequently used as functional platforms for biosensor preparation.
All the amino groups present on the surface are not available in reactive forms, because surface amino groups interact with
remaining unreacted surface silanol groups. Such nonspecific interactions might reduce the efficiency of chemical immobilization
of biomolecules such as DNA, enzymes, antibodies, etc., in biosensor fabrication. To improve immobilization efficiency we
have used additional surface silanization with alkylsilane (capping) to convert the remaining silanol groups into Si–O–Si
linkages, thereby liberating the amino groups from nonspecific interaction with the silanol groups. We prepared different
types of capped amine surface and evaluated the effect of capping on immobilization efficiency by investigating the fluorescence
intensity of Cy3-NHS (N-hydroxysuccinimide) dye that reacted with amino groups. The results indicate that most of the capped amine surfaces resulted
in enhanced efficiency of immobilization of Cy3-NHS compared with the untreated control amine surface. We found a trend that
trialkoxysilanes had greater capping effects on immobilization efficiency than monoalkoxysilanes. It was also found that the
aliphatic chain of alkylsilane, which does not participate in the capping of the silanol, had an important function in enhancing
immobilization efficiency. These results would be useful for preparation of an amine-modified surface platform, with enhanced
immobilization efficiency, which is essential for developing many kinds of biosensors on a silica matrix.
Enhancement of amine funtionality by capping with alkylsilane 相似文献
129.
130.
Akihiro Takezawa Shinji Nishiwaki Mitsuru Kitamura 《Journal of computational physics》2010,229(7):2697-2718
This paper discusses a structural optimization method that optimizes shape and topology based on the phase field method. The proposed method has the same functional capabilities as a structural optimization method based on the level set method incorporating perimeter control functions. The advantage of the method is the simplicity of computation, since extra operations such as re-initialization of functions are not required. Structural shapes are represented by the phase field function defined in the design domain, and optimization of this function is performed by solving a time-dependent reaction diffusion equation. The artificial double well potential function used in the equation is derived from sensitivity analysis. The proposed method is applied to two-dimensional linear elastic and vibration optimization problems such as the minimum compliance problem, a compliant mechanism design problem and the eigenfrequency maximization problem. The numerical examples provided illustrate the convergence of the various objective functions and the effect that perimeter control has on the optimal configurations. 相似文献