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181.
Robert J.P. Corriu Vijam Huynh Joël J.E. Moreau Magali Pataud-Sat 《Tetrahedron letters》1982,23(32):3257-3260
N,N-bis(silyl)enamines react with electrohiles in the presence of catalytic amounts of nucleophile. The reaction of carbonyl compounds catalyzed by fluoride ion provides an interesting route to 2?aza?1,3?dienes. The methoxide ion catalyzed reaction of N,N—dimethyl- formade gives rise to enamidines. 相似文献
182.
Synthesis of a thermally stable hybrid acene-thiophene organic semiconductor via a soluble precursor
Nicolas Y Blanchard P Roncali J Allain M Mercier N Deman AL Tardy J 《Organic letters》2005,7(16):3513-3516
An acene fused-thiophene hybrid p-semiconductor exhibiting high thermal stability has been synthesized via a soluble precursor bearing sterically interacting trimethylsilyl groups. [structure: see text] 相似文献
183.
Albert J Bosque R Cadena JM Delgado S Granell J Muller G Ordinas JI Font Bardia M Solans X 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(10):2279-2287
The synthesis of P,P'-dimesityl-P,P'-diphenyldiphosphine and benzylmesitylphenylphosphine is described as well as the resolution of the latter ligand by means of homochiral organometallic complexes. The absolute configuration of the phosphine is assigned by NMR spectra, using the homochiral palladacycle as a reference point. The configuration has been confirmed by single crystal X-ray diffraction. Molecular mechanics calculations were performed in [PdCl-(R)-(+)-C10H6CH(Me)NH2(PBnMesPh)], and showed that the rotation around the Pd-P bond is restricted in this complex. [Pd(eta3-2-MeC3H4)Cl(PBnMesPh)] was obtained and used as a precursor in the catalytic hydrovinylation of styrene. Benzylmesitylphenylphosphine has a strong tendency to form phosphapalladacycles by activation of one of the ortho-methyl groups. The formation of this metallacycle from cyclopalladated N-donor derivatives by a ligand-exchange reaction is also described. 相似文献
184.
Ramn Moreno‐Tost Jos Santamaría‐Gonzlez Enrique Rodríguez‐Castelln Antonio Jimnez‐Lpez Miguel A. Auti Marisol Carreras Glacial Giselle Auti Castro Magali Guerra 《无机化学与普通化学杂志》2005,631(11):2253-2257
The catalytic selective reduction of NO over metal‐exchanged (ZnII, AgI) natural zeolites (mordenite and clinoptilolite) from Cuba using NH3 as a reducing agent in the presence of excess oxygen was studied. Both transition metals slightly improve the catalytic performance for the NO reduction. ZnII‐exchanged zeolites exhibit a moderate catalytic activity, with conversions of NO of ≈58 % and high selectivity to N2 at high temperatures. 相似文献
185.
Barkigia KM Palacio M Sun Y Nogues M Renner MW Varret F Battioni P Mansuy D Fajer J 《Inorganic chemistry》2002,41(22):5647-5649
The synthesis, characterization, and molecular structures of the first air-stable, hexacoordinated high spin Fe(II) porphyrins (1) with axial alcohols are reported (1 = Fe(II) meso-tetrakis(o-dichlorophenyl)-beta-octanitroporphyrin). The structure of 1 with two axial waters is also presented. The very different conformations and metrics observed with the two types of ligands illustrate the acute interplay between ligands, conformations, and spin states in Fe porphyrins. 相似文献
186.
Chiara Mauriello Jimenez Yolanda Galàn Rubio Valentin Saunier David Warther Vanja Stojanovic Laurence Raehm Céline Frochot Philippe Arnoux Marcel Garcia Alain Morère Nadir Bettache Marie Maynadier Philippe Maillard Magali Gary-Bobo Jean-Olivier Durand 《Journal of Sol-Gel Science and Technology》2016,79(3):447-456
187.
Reversible Guest Uptake/Release by Redox‐Controlled Assembly/Disassembly of a Coordination Cage
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Vincent Croué Dr. Sébastien Goeb Dr. György Szalóki Magali Allain Prof. Marc Sallé 《Angewandte Chemie (International ed. in English)》2016,55(5):1746-1750
Controlling the guest expulsion process from a receptor is of critical importance in various fields. Several coordination cages have been recently designed for this purpose, based on various types of stimuli to induce the guest release. Herein, we report the first example of a redox‐triggered process from a coordination cage. The latter integrates a cavity, the panels of which are based on the extended tetrathiafulvalene unit (exTTF). The unique combination of electronic and conformational features of this framework (i.e. high π‐donating properties and drastic conformational changes upon oxidation) allows the reversible disassembly/reassembly of the redox‐active cavity upon chemical oxidation/reduction, respectively. This cage is able to bind the three‐dimensional B12F122? anion in a 1:2 host/guest stoichiometry. The reversible redox‐triggered disassembly of the cage could also be demonstrated in the case of the host–guest complex, offering a new option for guest‐delivering control. 相似文献
188.
It has been reported that cellulose is better dissolved in NaOH-water when a certain amount of urea is added. In order to
understand the mechanisms of this dissolution and the interactions between the components, the binary phase diagram of urea/water,
the ternary urea/NaOH/water phase diagram and the influence of the addition of microcrystalline cellulose in urea/NaOH/water
solutions were studied by DSC. Urea/water solutions have a simple eutectic behaviour with a eutectic compound formed by pure
urea and ice (one urea per eight water moles), melting at −12.5 °C. In the urea/NaOH/water solutions, urea and NaOH do not
interact, each forming their own eutectic mixtures, (NaOH + 5H2O, 4H2O) and (urea, 8H2O), as found in their binary mixtures. When the amount of water is too low to form the two eutectic mixtures, NaOH is attracting
water at the expense of urea. In the presence of microcrystalline cellulose, the interactions between cellulose and NaOH/water
are exactly the same as without urea, and urea is not interacting with cellulose. A tentative explanation of the role of urea
is to bind water, making cellulose-NaOH links more stable.
Member of the European Polysaccharide Network of Excellence (EPNOE), 相似文献
189.
Magali Folch-Gabayet James Wright 《Transactions of the American Mathematical Society》2008,360(3):1661-1679
We prove , bounds for and where , are rational functions. Our bounds depend only on the degrees of the polynomials and, in particular, they do not depend on the coefficients of these polynomials.
190.
Michael Bley Magali Duvail Philippe Guilbaud Christophe Penisson Johannes Theisen Jean-Christophe Gabriel 《Molecular physics》2018,116(15-16):2009-2021
ABSTRACTHerein, an approach for simulating phase diagrams of binary mixtures is presented, where a bulk liquid and its corresponding vapour phase are simulated by means of molecular dynamics using explicit polarisation. Time-averaged density profiles for the pure compounds and mixtures at different mole fractions provide information about the spatial distribution in the bulk liquid and the amount of evaporated species in the adjacent vapour phase. The activities in the liquid phase are calculated from the mean vapour phase densities at a given composition, providing a good qualitative agreement compared to experimental data and the precision of the method follows a previously developed Poisson model of evaporation. With the Redlich–Kister approach for the activities in a binary mixture, the directly obtained activities are fitted providing corrected activity coefficients of the two species. This method is applied to ethanol water mixtures at different mole fractions. The obtained structural data are in good agreement with experimental data and time-averaged density profiles provide a detailed insight into the composition of the liquid–vapour interface. An azeotropic point is obtained for an excess concentration of ethanol at 87% as percentage by mass compared to the experimental value of 95%. 相似文献