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111.
M. Zh. Ovakimyan G. Ts. Gasparyan M. L. Movsisyan M. R. Grigoryan 《Russian Chemical Bulletin》2012,61(12):2338-2343
2-Hydrazinoethyl- and 4-hydrazinobut-2-enylphosphonium salts undergo spontaneous dehydrogenation leading to the corresponding hydrazones or diazenes, depending on the structure of the starting compounds or the reaction conditions. A possible mechanism of the trans-formations is discussed. 相似文献
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Daniel W. Kulp Sabareesh Subramaniam Jason E. Donald Brett T. Hannigan Benjamin K. Mueller Gevorg Grigoryan Alessandro Senes 《Journal of computational chemistry》2012,33(20):1645-1661
We present the Molecular Software Library (MSL), a C++ library for molecular modeling. MSL is a set of tools that supports a large variety of algorithms for the design, modeling, and analysis of macromolecules. Among the main features supported by the library are methods for applying geometric transformations and alignments, the implementation of a rich set of energy functions, side chain optimization, backbone manipulation, calculation of solvent accessible surface area, and other tools. MSL has a number of unique features, such as the ability of storing alternative atomic coordinates (for modeling) and multiple amino acid identities at the same backbone position (for design). It has a straightforward mechanism for extending its energy functions and can work with any type of molecules. Although the code base is large, MSL was created with ease of developing in mind. It allows the rapid implementation of simple tasks while fully supporting the creation of complex applications. Some of the potentialities of the software are demonstrated here with examples that show how to program complex and essential modeling tasks with few lines of code. MSL is an ongoing and evolving project, with new features and improvements being introduced regularly, but it is mature and suitable for production and has been used in numerous protein modeling and design projects. MSL is open‐source software, freely downloadable at http://msl‐libraries.org . We propose it as a common platform for the development of new molecular algorithms and to promote the distribution, sharing, and reutilization of computational methods. © 2012 Wiley Periodicals, Inc. 相似文献
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Z. A. Grigoryan A. T. Karapetyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2014,49(6):293-296
The behavior of a mixture of short fragments of double-stranded DNA and a flexible-chain polymer is addressed. The role of the DNA double helix in the formation of the crystalline phase in the flexible-chain polymer’s melt is examined. It is shown that the presence of DNA rigid fragments in melt results in increase in the melting temperature. A shift of the melting temperature of a perfect crystal with respect to the pure melt of polymer is calculated. 相似文献
116.
M. Zh. Ovakimyan G. Ts. Gasparyan M. R. Grigoryan A. S. Bichakhchyan 《Russian Journal of General Chemistry》2014,84(3):496-500
(4-Bromobut-2-en-1-yl)triphenylphosphonium bromide reacted with phenylhydrazine at 2°C in the presence of sodium carbonate to form triphenyl[4-(2-phenylhydrazinylidene)but-2-en-1-yl]phosphonium bromide in 62% yield. The obtained N-phenylhydrazine derivatives cyclized into the corresponding pyrazoline derivatives of phosphonium salts. Unlike phenylhydrazine, ethylhydrazine reacted with (4-bromobut-2-ene-1-yl)triphenylphosphonium bromide under the same conditions to afford triphenyl[(1-ethyl-4,5-dihydro-1Hpyrazol-3-yl)methyl]- and -[(1-ethyl-1H-pyrazol-3-yl)methyl]phosphonium bromides in yields of 60 and 40%. 相似文献
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K. M. Gitis V. N. Kornyshev E. S. Shpiro A. A. Grigoryan G. V. Isagulyants Kh. M. Minachev D. P. Shashkin 《Russian Chemical Bulletin》1989,38(7):1349-1354
1. | Selective hydrogenation of piperylene into n-amylenes (300C) on applied nickel sulfide was studied in the pulsed mode. It was found that NiS/SiO2 is more selective than NiS/Al2O3. |
2. | Treatment of applied NiS with air at 300–500C oxidizes a significant portion of NiS into NiSO4, which gives the catalyst hydroisomerizing properties and permits obtaining up to 44% isoamylenes from piperylene. In contrast to oxidized NiS/SiO2, oxidized NiS/Al2O3 retains hydroisomerizing activity for a much longer time, which is due to the higher resistance of NiSO4 to reduction on Al2O3 than on SiO2. |
3. | The data obtained indicate that reduced nickel atoms are the active sites of selective hydrogenation, while sulfur, sulfide or sulfate, is the surface modifier. |
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Okina E. V. Tarasova O. V. Balandina A. V. Grigoryan K. A. Selivanova Yu. M. Gorbunova A. V. 《Russian Journal of General Chemistry》2019,89(5):918-923
Russian Journal of General Chemistry - Immobilization of acridine and its derivatives (9-phenylacridine and N-methyl-9-phenylacridinium iodide) has been studied and quantitative data on physical... 相似文献
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