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排序方式: 共有382条查询结果,搜索用时 468 毫秒
21.
Chi‐Cheung Su Meinan He Jiayan Shi Rachid Amine Jian Zhang Khalil Amine 《Angewandte Chemie (International ed. in English)》2020,59(41):18229-18233
Despite the exceptionally high energy density of lithium metal anodes, the practical application of lithium‐metal batteries (LMBs) is still impeded by the instability of the interphase between the lithium metal and the electrolyte. To formulate a functional electrolyte system that can stabilize the lithium‐metal anode, the solvation behavior of the solvent molecules must be understood because the electrochemical properties of a solvent can be heavily influenced by its solvation status. We unambiguously demonstrated the solvation rule for the solid‐electrolyte interphase (SEI) enabler in an electrolyte system. In this study, fluoroethylene carbonate was used as the SEI enabler due to its ability to form a robust SEI on the lithium metal surface, allowing relatively stable LMB cycling. The results revealed that the solvation number of fluoroethylene carbonate must be ≥1 to ensure the formation of a stable SEI in which the sacrificial reduction of the SEI enabler subsequently leads to the stable cycling of LMBs. 相似文献
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Numerical modeling of multiphase flow generally requires a special procedure at the solid wall in order to be consistent with Young's law for static contact angles. The standard approach in the lattice Boltzmann method, which consists of imposing fictive densities at the solid lattice sites, is shown to be deficient for this task. Indeed, fictive mass transfer along the boundary could happen and potentially spoil the numerical results. In particular, when the contact angle is less than 90 degrees, the deficiencies of the standard model are major. Various videos that demonstrate this behavior are provided (Supporting Information). A new approach is proposed and consists of directly imposing the contact angle at the boundaries in much the same way as Dirichlet boundary conditions are generally imposed. The proposed method is able to retrieve analytical solutions for static contact angles in the case of straight and curved boundaries even when variable density and viscosity ratios between the phases are considered. Although the proposed wetting boundary condition is shown to significantly improve the numerical results for one particular class of lattice Boltzmann model, it is believed that other lattice Boltzmann multiphase schemes could also benefit from the underlying ideas of the proposed method. The proposed algorithm is two‐dimensional, and the D2Q9 lattice is used. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
24.
H. Eleuch N. Rachid 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,57(2):259-264
We study the photon statistics of the field emitted from a semiconductor microcavity containing a quantum well in the non-linear
regime. The q-deformed boson concept (quon) allows us to derive an analytical expression of the autocorrelation function in
non-resonant pumping. The dependence of the dynamical behavior of the autocorrelation function on the q deformation parameter
is discussed. 相似文献
25.
Fadela Iftene Ghislain David Bernard Boutevin Rémi Auvergne Ali Alaaeddine Rachid Meghabar 《Journal of polymer science. Part A, Polymer chemistry》2012,50(12):2432-2443
Three new vinyl ether monomers containing phosphonate moieties were synthesized from transetherification reaction. We showed that the yield was dependent on the spacer length between the vinyl oxy group and the phosphonate moieties: when the spacer is a single methylene side reaction may occur, leading to the formation of acetal compounds. Free‐radical copolymerizations of phosphonate‐containing vinyl ether monomers with maleic anhydride were carried out, leading to alternated copolymers of rather low molecular weights (from 1000 to 7000 g/mol). Both gel permeation chromatography and 31P NMR analyses enhanced possible intramolecular transfer reactions occurring from the phosphonate moieties. Kinetic investigation showed that the electron‐withdrawing character of the phosphonate moieties tends to decrease the rate of copolymerization. Nevertheless, almost complete monomers conversion was reached after 30 min of reaction with dimethyl vinyloxyethylphosphonate (VEC2PMe). Then, radical copolymerization of VEC2PMe with a series of electron‐accepting monomers, that is, dibutyl maleate, dibutylitaconate, itaconic anhydride, butyl maleimide, and methyl maleimide, led to a series of alternated copolymers. From kinetic investigation, we showed that the higher the electron‐accepting effect, the faster the vinyl ether consumption and the higher the molecular weights. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
26.
Falck JR Barma DK Baati R Mioskowski C 《Angewandte Chemie (International ed. in English)》2001,40(7):1281-1283
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Zaid Faska Aicha Bellioua Mohamed Bouklah Lhou Majidi Rachid Fihi Abdelahamid Bouyanzer Belkheir Hammouti 《Monatshefte für Chemie / Chemical Monthly》2008,139(12):1417-1422
The inhibitive action of pulegone and pulegone oxide toward acid corrosion of steel in molar hydrochloric acid was studied
by weight loss measurements, potentiodynamic polarization, and impedance spectroscopy (EIS) methods. The pulegone is extracted
starting from oil of Pennyroyal Mint (Mentha pulegium). The natural compound was found to delay the corrosion rate. The pulegone oxide is prepared by oxidation of pulegone. The
inhibition efficiency was found to increase with the inhibitor content to attain 81 and 75% at 5 g dm−3 for pulegone and pulegone oxide. The increase in temperature leads to an increase in the inhibition efficiency of the natural
compared.
Correspondence: Belkheir Hammouti, Laboratoire de chimie Appliquée & Environnement, Faculté des Sciences, B.P. 717, 60000
Oujda, Morocco. 相似文献
29.
Antonio Herrera Nazario Martín Rachid Chioua Ángel Sánchez-Vázquez John Almy 《Tetrahedron》2009,65(8):1697-2715
Two alternative methods for the preparation of new pyrimidine Diels-Alder cycloadducts from the readily available 2,4-bis(methylsulfanyl)-5,6-dihydrocyclobuta[d]pyrimidine are presented. In the first method, the in situ generated pyrimidine ortho-quinodimethane reacts with various dienophiles to form the respective cycloadducts bearing two methylthio groups, which can be easily replaced by other functional groups. In the second method, one or both of the methylsulfanyl groups of the starting pyrimidine are replaced first and the resulting functionalized pyrimidines are able to undergo Diels-Alder cyclization with different dienophiles to form pyrimidine cycloadducts. These alternative synthetic strategies provide access to a wide variety of pyrimidine cycloadducts with a different substitution pattern on the pyrimidine ring. Yield data indicate that the electronic nature of the functional groups strongly influence the efficiency of the cycloaddition reaction. 相似文献
30.