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101.
Ewa Rozycka‐Sokolowska Bernard Marciniak Volodymyr Pavlyuk 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o162-o164
The planar benzene rings in the title compound, C15H16O2, are inclined at an angle of 82.61 (9)° to one another. There are two intramolecular hydrogen bonds of types O—H⋯π and C—H⋯O. The molecules are linked by strong O—H⋯O hydrogen bonds into a one‐dimensional network, which is compared with that of related compounds. 相似文献
102.
Pavlo Solokha Serena De Negri Adriana Saccone Volodymyr Pavlyuk Bernard Marciniak Jean‐Claude Tedenac 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(2):i13-i16
Single crystals of diterbium dinickel trimagnesium, Tb2Ni2Mg3, were synthesized from the elements by induction melting. The novel compound crystallizes in the space group Cmmm with one Mg atom of site symmetry mmm and the Tb, Ni and other Mg atom in m2m positions. This ternary compound represents a new structure type that is derived from Ru3Al2B2 by way of Wyckoff site distribution. The two‐layer structure of Tb2Ni2Mg3 is a new representative of a homologous linear structure series of general formula R′k+nX2nR′′2m+k based on structural fragments of the α‐Fe, CsCl and AlB2 structure types. The Tb atoms in the structure are enclosed in 17‐vertex polyhedra, while rhombododecahedra and distorted rhombododecahedra surround the Mg atoms, and equatorially tricapped trigonal prisms form around the Ni atoms. All interatomic distances indicate metallic type bonding. 相似文献
103.
This paper provides several extensions of the notion of dimension of a simple game and proves the existence of a minimum subclass
of weighted games with the property that every simple game can be expressed as their intersection. Some further generalizations
lead to the new concept of codimension which is obtained by considering the union instead of the intersection as the basic
operation. 相似文献
104.
Jarogniew Bartoszewicz Gordon L. Hug Marek Pietrzak Halina Kozubek Jerzy Paczkowski Bronislaw Marciniak 《Journal of polymer science. Part A, Polymer chemistry》2008,46(24):8013-8022
The mechanism of the benzophenone‐sensitized photooxidation of phosphonium salts of (phenylthio)acetic acid was studied as a means for understanding how these salts function as coinitiators in the free‐radical photopolymerization of vinyl monomers. Both steady‐state and nanosecond flash photolytic methods were used to determine, in a quantitative manner, the mechanism of primary and secondary photoreactions for three quaternary phosphonium salts containing butyl and/or phenyl groups, i.e., P+(C4H9)4, P+(C4H9)(C6H5)3, and P+(C6H5)4. It was found that the initial polymerization rates were the same for all three phoshonium salts of (phenylthio)acetic acid and were equal to those found previously for tetralkyl ammonium salts. The polymerization rates were more than twice the rates found for direct initiation by benzophenone and by the benzophenone‐(phenylthio)acetic acid initiating system. These results correlate well with the large quantum yields of ?CH2SC6H5 radicals (the main initiating radicals) found in the complementary photochemical investigation. It was found that a detailed knowledge of the photochemical reactions in the photoinitiating systems was critical to understand the kinetics of polymerization. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8013–8022, 2008 相似文献
105.
The modal characteristics of planar waveguides with photonic band gap guiding properties are studied. It is demonstrated that a slight deviation from the periodicity in the photonic band gap multilayers can result in multimode transmission within the guiding layer. Possible applications of the results for avoiding single mode regime destruction due to fabrication process imperfection, as well as for designing such waveguides for conventional and emerging new applications of multimode photonic devices, are pointed out. 相似文献
106.
107.
Supported by Canadian NSERC Grant A-5300 and Polish Scientific Grant 211399101. 相似文献
108.
The title compound is prepared from the elements (670 K, 3 d; annealing at 1070 K, 3 h) and its structure is determined by single crystal XRD. 相似文献
109.
Bodzioch A Marciniak B Różycka-Sokołowska E Jeszka JK Uznański P Kania S Kuliński J Bałczewski P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(16):4866-4876
A new modification of the Friedel-Crafts type intramolecular cyclization involving O-protected ortho-acetal diarylmethanols as a new type of reactant, was carried out for the first time in a medium containing a large amount of water at room temperature and enabled synthesis of a series of electron-rich, hexahydroxylated 10-O-R-substituted anthracenes, where R is an alkyl (Me, nBu, n-C(16)H(33)) or arylalkyl group (CH(2)Ph, CH(2)-2-Napht, CH(2)C(6)H(4)CH(2)OAr) and also evaluation of their electronic and optoelectronic properties in solution, crystal, and solid thin film. In this transformation, a central 10-O-R-substituted benzene ring was formed, fused to rings originating from two independent aromatic aldehydes. The reaction proceeded via two identified mechanisms involving acetal and/or free aldehyde groups. The acid sensitive acetal and dibenzyl alkoxy functions have never been used together in the intramolecular Friedel-Crafts type cyclization. The new compounds revealed deep blue fluorescence and quantum yields in solution around 0.3. The electrical properties investigated for thin films obtained by vacuum deposition on glass were 10-O-R-substituent dependent and showed much faster transient current decay in the case of the 10-O-CH(2)Ph derivative than for the material with a 10-O-Me substituent (the lifetime of charge carriers was 25 times shorter in this case). The AFM images of thin films, Stokes shifts, and X-ray analysis of π-stacking interactions in crystals of the new materials have been also obtained. 相似文献
110.