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111.
This study deals with the performance of projective interior point methods for linear semidefinite program. We propose a modification in the initialization phases of the method in order to reduce the computation time.This purpose is confirmed by numerical experiments showing the efficiency which are presented in the last section of the paper. 相似文献
112.
Abdelkrim HasnaouiThomas Godin Emmanuel CagniotMichael Fromager Andrew Forbes Kamel Aït-Ameur 《Optics Communications》2012,285(24):5268-5275
Laser beams of a single high-order transverse mode have been of interest to the laser community for several years now. In order to achieve such a mode as the fundamental mode of the cavity, mode selecting elements in the form of a phase or amplitude mask are often placed inside the resonator. Such elements have the role to impose one or several zeros of intensity of the desired mode. In this paper, we consider the use of the most simple phase (amplitude) mask which is a transparent π-plate (absorbing ring) set inside a diaphragmed laser cavity for selecting a pure LGp0 mode of radial order, p. We analyse, for each type of mask, the origin of the transverse mode selection, and contrary to what one might expect we find that it is not necessary the absorbing mask that results in the highest losses. 相似文献
113.
Stéphane Bouchonnet Sophie Bourcier Yasmine Souissi Christophe Genty Michel Sablier Pascal Roche Véronique Boireau Valérie Ingrand 《Journal of mass spectrometry : JMS》2012,47(4):439-452
The degradation of the chloracetamide herbicide acetochlor has been studied under simulated ozonation treatment plant conditions. The degradation of acetochlor included the formation of several degradation products that were identified using GC/ion‐trap mass spectrometry with EI and CI and HPLC/electrospray‐QqTOF mass spectrometry. Thirteen ozonation products of acetochlor have been identified. Ozonation of the deuterated herbicide combined to MSn and high‐resolution mass measurement allowed effective characterization of the degradation products. At the exception of one of them, the product B (2‐chloro‐2', ethyl‐6', methyl‐acetanilide), none of the identified degradation products has been already reported in the literature. Post‐ozonation kinetics studies revealed that the concentrations of most degradation products evolved noticeably with time, particularly during the first hours following the ozonation treatment. This raises concerns about the fate of degradation products in the effluents of treatment plants and suggests the need for a better control on these products if their toxicity was demonstrated. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
114.
Bouchonnet S Bourcier S Souissi Y Genty C Sablier M Roche P Boireau V Ingrand V 《Journal of mass spectrometry : JMS》2012,47(4):439-452
The degradation of the chloracetamide herbicide acetochlor has been studied under simulated ozonation treatment plant conditions. The degradation of acetochlor included the formation of several degradation products that were identified using GC/ion-trap mass spectrometry with EI and CI and HPLC/electrospray-QqTOF mass spectrometry. Thirteen ozonation products of acetochlor have been identified. Ozonation of the deuterated herbicide combined to MS(n) and high-resolution mass measurement allowed effective characterization of the degradation products. At the exception of one of them, the product B (2-chloro-2', ethyl-6', methyl-acetanilide), none of the identified degradation products has been already reported in the literature. Post-ozonation kinetics studies revealed that the concentrations of most degradation products evolved noticeably with time, particularly during the first hours following the ozonation treatment. This raises concerns about the fate of degradation products in the effluents of treatment plants and suggests the need for a better control on these products if their toxicity was demonstrated. 相似文献
115.
Mohamed El Kodadi Abdelkrim Ramdani Malek Fouad Driss Eddike Monique Tillard Claude Belin 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):o735-o737
The crystal structure of the title compound, C18H23N5O·H2O, shows molecules containing a phenol group linked perpendicularly to a roughly planar fragment comprising two pyrazole rings. Molecules are stacked perpendicular to the [101] direction, with their phenol groups disposed alternately. The molecular packing in the crystal is stabilized by hydrogen bonding involving water molecules. 相似文献
116.
Benoit Boulinguiez Abdelkrim Bouzaza Smail Merabet Dominique Wolbert 《Journal of photochemistry and photobiology. A, Chemistry》2008,200(2-3):254-261
Photocatalytic treatment of polluted air by odorous contaminants – ammonia and butyric acid – is investigated in a plug-flow reactor covered by non-woven fiber textile coated with TiO2. For the first time, the single-component degradation pathway of ammonia by photocatalysis at ambient condition is highlighted. It appears fundamentally different compared to the butyric acid degradation pathway. The ammonia degradation pathway highlights a possible auto-accelerated behavior of the reaction. The chemical degradation kinetics follows the Langmuir–Hinshelwood model, though observed oxidation rates depend upon flow conditions in the reactor. Thus, interpretation of degradation results through a model considering the Langmuir–Hinshelwood approach and mass transfer phenomenon is presented. This model succeeds with a pair of determined kinetic constants and mass transfer coefficients to describe experimental results for different flow rates and for both pollutants, though they present wide dissimilarities in their degradation pathways. 相似文献
117.
Yasmine B. Sanderson 《Journal of Algebraic Combinatorics》2000,11(3):269-275
We show that the specialization of nonsymmetric Macdonald polynomials at t = 0 are, up to multiplication by a simple factor, characters of Demazure modules for
. This connection furnishes Lie-theoretic proofs of the nonnegativity and monotonicity of Kostka polynomials. 相似文献
118.
Synthesis and Characterization of the New Lacunar Zincophosphate [C6H10N2][ZnP2O8H2]·0.6H2O 下载免费PDF全文
Nadjet Chouat Emanuelle Ligner Mohamed Sassi Mohammed Abdelkrim Hasnaoui Laure Michelin Ludovic Josien Claire Marichal Abdelkader Bengueddach Joël Patarin Jean‐Louis Paillaud 《无机化学与普通化学杂志》2017,643(22):1793-1800
The new zincophosphate of chemical formula [C6H10N2][ZnP2O8H2] · 0.6H2O was hydrothermally synthesized with p‐phenylenediamine as structure‐directing agent. The title compound crystallizes in the trigonal symmetry (proposed space group P3m1), where inorganic zincophosphate chains form layers due to the half occupancy of the unique crystallographic zinc site. The layers are separated from each other by p‐phenylenediammonium dications with hydrogen bonding scheme involving the ammonium protons that reveals a pillar‐like 3D structure aspect. The compound was characterized by powder X‐ray diffraction, multinuclear solid‐state NMR, scanning electron microscopy, chemical analysis, and thermogravimetric analysis. 相似文献
119.
120.