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1.
A study of body waves in fractured porous media saturated by two fluids is presented. We show the existence of four compressional and one rotational waves. The first and third compressional waves are analogous to the fast and slow compressional waves in Biot's theory. The second compressional wave arises because of fractures, whereas the fourth compressional wave is associated with the pressure difference between the fluid phases in the porous blocks. The effects of fractures on the phase velocity and attenuation coefficient of body waves are numerically investigated for a fractured sandstone saturated by air and water phases. All compressional waves except the first compressional wave are diffusive-type waves, i.e., highly attenuated and do not exist at low frequencies.Now at Izmir Institute of Technology, Faculty of Engineering, Gaziosmanpasa Bulvari, No.16, Cankaya, Izmir, Turkey. 相似文献
2.
A classical density functional formalism has been developed to predict the position-orientation number density of structured fluids. It is applied to the liquid-vapor interface of pure water, where it consists of a classical term, a gradient correction, and an anisotropic term that yields order through density gradients. The model is calibrated to predict that water molecules have their dipole moments almost parallel to a planar interface, while the molecular plane is parallel to it on the liquid side and perpendicular to it on the vapor side. For a planar interface, the surface tension obtained is twice its experimental value, while the surface potential is in qualitative agreement with that calculated by others. The model is also used to predict the orientation of water molecules near the surface of droplets, as well as the dependence of equilibrium vapor pressure around them on their size. 相似文献
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4.
A distance based measure of dependence is proposed for stable distributions that completely characterizes independence for a bivariate stable distribution. Properties of this measure are analyzed, and contrasted with the covariation and co-difference. A sample analog of the measure is defined and demonstrated on simulated and real data, including time series and distributions in the domain of attraction of a stable law. 相似文献
5.
Nader Noroozi Pesyan Marziyeh Bagheri Ertan Şahin Tuncay Tunç 《Journal of the Iranian Chemical Society》2014,11(5):1429-1437
The use of DCC, triethylamine and 4-dimethylaminopyridine in dichloromethane provides a general and standard one-pot procedure for the O-acylation of cyclic β-dicarbonyl compound derivatives (1) with palmitic and stearic acids which have long hydrocarbon tails, to synthesis of new type of fatty acid derivative in good to excellent yields. Structure elucidation was carried out by FT-IR, 1H NMR and 13C NMR spectroscopy techniques. The acyl migration was also found in results and the corresponding structure was characterized by X-ray crystallography. A proposed mechanism was discussed for the formation of products. 相似文献
6.
Regioselective One‐pot Synthesis of New Unsymmetric Spiro Dihydrofurans in the Reaction of Mixed Two Different Cyclic β‐Dicarbonyl Compounds with BrCN and Aldehydes in the Presence of Et3N
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Crossed one‐pot reaction of mixed cyclic β‐dicarbonyl with various aldehydes in the presence of cyano gen bromide and triethylamine leads to the selective and efficient formation of crossed new unsymmetri cal spiro dihydrofurans at room temperature. The products were obtained in good to excellent yields. Structure elucidation was carried out by 1H NMR, 13C NMR, FT‐IR spectroscopy, Mass analyses and X‐ray crystallography technique. A proposed mechanism was discussed for the formation of products. 相似文献
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8.
Tuncay TuncÛ Musa Sar Rahmi Yagbasan Habibe Tezcan Ertan SÛahin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o192-o193
Molecules of the title compound (alternative name p‐methoxybenzaldehyde 2‐pyridylhydrazone), C13H13N3O, adopt an E configuration about the azomethine C=N double bond. Molecules are almost planar, the dihedral angle between the pyridine and methoxyphenyl rings being only 6.19 (12)°. Pairwise N—H⃛N hydrogen bonds [R(8) in graph‐set notation] link centrosymmetrically related molecules into discrete pairs. 相似文献
9.
Büşra Kaya Duygu Akyüz Tuncay Karakurt Onur Şahin Atıf Koca Bahri Ülküseven 《应用有机金属化学》2020,34(11):e5930
New cobalt complexes, Co1 and Co2 , were synthesized starting from acetylacetone-S-methylthiosemicarbazone. The square planar cobalt(II) and octahedral cobalt(III) complexes were characterized by FT-IR, UV–visible, 1H NMR, and X-ray diffraction spectroscopies and mass spectrometry. Frontier orbitals of the complexes were theoretically obtained to better understand the complex structures and intermolecular interactions. The electrochemical behaviors of Co1 and Co2 were investigated and the results were evaluated by comparing with each other and with similar published compounds to determine their possible usage in various electrochemical technologies, such as energy storage devices, electrocatalysts, and electrosensors. Metal-based oxidation at around 0 V and metal-based reduction at around −1.0 V indicated that these complexes are valuable for the proposed applications. By determining the trolox equivalent antioxidant capacity and the radical scavenging activity of the cobalt complexes, the compatibility between the antioxidant qualification, redox, and theoretical calculation results was discussed. 相似文献
10.
Çağlar Tuncay 《Central European Journal of Physics》2006,4(1):58-72
Proposed in this paper is an original method assuming potential and kinetic energies for prices and for the conservation of
their sum that has been developed for forecasting exchanges. Connections with a power law are shown. Semiempirical applications
on the S&P500, DJIA, and NASDAQ predict a forthcoming recession in them. An emerging market, the Istanbul Stock Exchange index
ISE-100 is found harboring a potential to continue to rise. 相似文献