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Gómez-Lor B Alonso B Omenat A Serrano JL 《Chemical communications (Cambridge, England)》2006,(48):5012-5014
Discotic liquid crystals based on triindole, a novel redox active central core, have been synthesized and their mesomorphic behaviour investigated. 相似文献
54.
The photolysis of 10,10-difluorophenanthren-9(10H)-one 1 in different solvents shows that the major competing reaction of the diradical formed by α-cleavage: recombination and hydrogen atom abstraction depends on the hydrogen atom donating ability of the solvent. Photolysis of 1 in cyclohexane in the presence of air or oxygen leads mainly to α-cleavage while photoreduction with the formation of 10-fluoro-9-phenanthrol occurs when the solution is deaerated prior to irradiation. In acetonitrile, a poor hydrogen donor, recombination of the diradical back to starting compound 1 is the sole process. 相似文献
55.
Gómez-Lor B González-Cantalapiedra E Ruiz M de Frutos O Cárdenas DJ Santos A Echavarren AM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(10):2601-2608
The C60 polyarenes 4, 5, 18 a, and 18 b have been synthesized from truxene by triple alkylation at C5, C10, and C15 followed by a palladium-catalyzed intramolecular arylation. The synthesis of "crushed fullerene" C60H30 (2) is the most efficient reported to date and proceeds in 33% overall yield. 相似文献
56.
Rosa Carballo Berta Covelo Ezequiel M. Vzquez‐Lpez Emilia García‐Martínez Alfonso Castieiras 《无机化学与普通化学杂志》2003,629(4):584-586
The structure of [Co2(μ‐OH)2(μ‐OAc)(OAc)2(dipyam)2]AcO · EtOH ( 1 ) has been determined by single‐crystal X‐ray analysis. The cationic complex may be described as a “di(μ‐hydroxo)(μ‐acetato)dicobalt(III)” core with chelating 2, 2′‐dipyridylamine and monodentate acetate ligands. The coordination polyhedron around each cobalt atom is a distorted octahedral. The dimers are linked in the crystal by N‐H···Oionic AcO and C‐H···Omonodentate AcO hydrogen bonds. Spectroscopic data are also presented. 相似文献
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Monge A Snejko N Gutiérrez-Puebla E Medina M Cascales C Ruiz-Valero C Iglesias M Gómez-Lor B 《Chemical communications (Cambridge, England)》2005,(10):1291-1293
Zn(C17H8F6O4) is the first example of a fluoro-lined nanotube organo-inorganic 3D polymeric chiral structure, which possesses two different types of isolated channels, one of them being laid out with a double spiral of CF3-groups from the ligand molecule; the structure is a new uninodal 4-connected net that only exists when bent ligands connect the centres, and the compound exhibits selective sorption and catalytic chiral recognition properties. 相似文献
59.
Kaewta Kaewtatip Metinee Poungroi Berta Holló Katalin Mészáros Szécsényi 《Journal of Thermal Analysis and Calorimetry》2014,115(1):833-840
In order to determine how the physicochemical properties of starch foams depend on the type of the starch used in baking process, starch foams were prepared using native starch and selected starch derivatives. The morphology, the density, the water adsorption capacity, the impact strength, and the thermal properties were determined for foams made from native starch, pregelatinized starch, hydroxypropylated starch with different degrees of substitution (DS = 0.015–0.025 and DS = 0.1), low distarch phosphate, medium distarch phosphate, and two cationic starch types (DS = 0.027–0.029 and DS = 0.029–0.033). The modified starch foams exhibited a more expanded structure with thinner cell walls than the foam made from native starch. The density of the native starch was 0.21 g cm?3 , while the density of the modified starch foams was lower, in the range of 0.14–0.17 g cm?3 except for the starch foam made from medium distarch phosphate. The thermal and physicochemical properties of the foams made from the other starch derivatives were dependent on the functional groups and the degree of cross-linking. The foam made from medium distarch phosphate had a significantly higher density and impact strength that was accompanied by a somewhat lower water adsorptivity. 相似文献
60.
Javier López Cacheiro Berta Fernández Domenico Marchesan Sonia Coriani Christof Hättig Antonio Rizzo 《Molecular physics》2013,111(1):101-110
Using augmented polarized correlation consistent basis sets extended with midbond functions, we evaluate the ground state interaction potential and the induced electric dipole polarizabilities and first and second hyperpolarizabilities of the He–Ar, Ne–Ar and He–Ne van der Waals complexes. For the calculation of the potential we resort to the coupled cluster singles and doubles (CCSD) model corrected for triple excitations, CCSD(T), whereas properties are evaluated with CCSD response theory. As a check of the quality of the potential, the rovibrational spectrum and the gas second virial coefficients are evaluated. The rovibrational spectra improve previously available theoretical results, although the dissociation energies are probably still slightly underestimated. For the gas second virial coefficients the agreement with experiment is satisfactory. The frequency dependence of the interaction (hyper)polarizabilities is analysed and a comparison with previous results on the mixed dimers and the pure gases is made. 相似文献