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101.
Oussama Kamal Tarik Eljaddi El Houssine EL Atmani Imane Touarssi Laurent Lebrun Miloudi Hlaïbi 《先进技术聚合物》2017,28(4):541-548
To conduct experiments related to the facilitated extraction phenomenon and recovery of vanadium ions VO2+, two grafted polymer membranes were prepared; containing respectively cholic acid and azithromycin as extractive agents and the obtained membranes were characterized. All experiments for the facilitated extraction phenomenon of these ions were carried out. Kinetic and thermodynamic models, based on the interaction of the substrate S (VO2+) with the extractive agent T, and the diffusion of the formed entity (TS) through the membrane were developed, to determine the macroscopic parameters, permeability P and initial fluxes J0, and the microscopic parameters, association constants Kass and apparent diffusion coefficients D*, related to the formation of entities TS and their diffusion. A clear evolution of these parameters, depending on various factors (substrate concentration C0, extractive agent concentration and feed and receiving phases temperature), and high permeabilities for this extraction phenomenon of VO2+ ions were observed for this membrane type. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
102.
Understanding the atomic processes governing the formation a heteroepitaxial interface is central to predict and control the basic physical and chemical properties of a variety of hetero‐structures. With this perspective, we address in this work the dynamic behavior of Ge atoms deposited on Si‐surfaces by molecular dynamics simulations using enhanced bond order potentials. We demonstrate that the deposition of Ge atoms on Si surface induces the competition between several processes including adsorption, desorption, and bulk and surface diffusion involving atomic exchange, substitution, and clustering. By tracking these process, the simulations provide unprecedented insights onto the assembly of the first atomic layer of Ge on Si, the nucleation, growth, and relaxation of islands and quantum dots as well as of defect generation in the bulk. 相似文献
103.
Antimicrobial Poly(2‐methyloxazoline)s with Bioswitchable Activity through Satellite Group Modification
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Dipl.‐Ing. Christian Krumm Dipl.‐Chem. Simon Harmuth Montasser Hijazi Britta Neugebauer Anne‐Larissa Kampmann Helma Geltenpoth Prof. Dr. Albert Sickmann Prof. Dr. Joerg C. Tiller 《Angewandte Chemie (International ed. in English)》2014,53(15):3830-3834
Biocides are widely used for preventing the spread of microbial infections and fouling of materials. Since their use can build up microbial resistance and cause unpredictable long‐term environmental problems, new biocidal agents are required. In this study, we demonstrate a concept in which an antimicrobial polymer is deactivated by the cleavage of a single group. Following the satellite group approach, a biocidal quaternary ammonium group was linked through a poly(2‐methyloxazoline) to an ester satellite group. The polymer with an octyl‐3‐propionoate satellite group shows very good antimicrobial activity against Gram‐positive bacterial strains. The biocidal polymer was also found to have low hemotoxicity, resulting in a high HC50/MIC value of 120 for S. aureus. Cleaving the ester satellite group resulted in a 30‐fold decrease in antimicrobial activity, proving the concept valid. The satellite group could also be cleaved by lipase showing that the antimicrobial activity of the new biocidal polymers is indeed bioswitchable. 相似文献
104.
From the existence of parallel spinor fields on Calabi-Yau, hyper-Kähler or complex flat manifolds, we deduce the existence of harmonic differential forms of different degrees on their minimal Lagrangian submanifolds. In particular, when the submanifolds are compact, we obtain sharp estimates on their Betti numbers which generalize those obtained by Smoczyk in [49]. When the ambient manifold is Kähler-Einstein with positive scalar curvature, and especially if it is a complex contact manifold or the complex projective space, we prove the existence of Kählerian Killing spinor fields for some particular spin c structures. Using these fields, we construct eigenforms for the Hodge Laplacian on certain minimal Lagrangian submanifolds and give some estimates for their spectra. These results also generalize some theorems by Smoczyk in [50]. Finally, applications on the Morse index of minimal Lagrangian submanifolds are obtained. 相似文献
105.
106.
Oussama Yahiaoui Dr. Lukáš F. Pašteka Bernadette Judeel Dr. Thomas Fallon 《Angewandte Chemie (International ed. in English)》2018,57(10):2570-2574
Herein we detail a practical synthesis of bullvalene and a variety of mono‐ and disubstituted analogues through cobalt‐catalysed [6+2] cycloaddition of cyclooctatetraene to alkynes, followed by photochemical di‐π‐methane rearrangement. The application of isomer‐network analysis, coupled with quantum‐chemical calculations, provides a powerful automated tool for predicting the properties of bullvalene isomer networks. 相似文献
107.
Rashidi M. M. Mahariq Ibrahim Alhuyi Nazari Mohammad Accouche Oussama Bhatti Muhammad Mubashir 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12301-12311
Journal of Thermal Analysis and Calorimetry - Heat exchangers (HEs) are used for several applications including chemical processes, power plants, air conditioning systems, etc. The performance of... 相似文献
108.
Six complexes of platinum(II) with a terdentate π-acceptor ligand, 2,6-(N-(n-hexyl)benzimidazol-2′-yl)pyridine), and different ethynylbenzene ligands were synthesized and investigated by means of optical absorption, luminescence, and time-resolved emission spectroscopy. These complexes display similar photophysical and electrochemical properties as previously investigated analogs with the 2,2′:6′,2″-terpyridine ligand. The energy of the luminescence band maximum is a function of the nature of the chemical substituents attached to the ethynylbenzene ligand, luminescence intensities and lifetimes correlate with the luminescence wavelength according to the energy-gap law. The emissive excited states of some of these complexes are quenched reductively with efficiencies near the diffusion-controlled limit, even for moderate electron donors such as phenothiazine or triphenylamine. A complex with a dimethylamine substituent attached to the ethynylbenzene ligand exhibits photophysical properties that are strongly dependent on the protonation state of the amine. A dimer complex with a diethynyl-substituted xanthene bridging ligand displays absorption and emission behavior that is essentially identical to that of some of the monomeric platinum complexes investigated in this work. Short Pt(II)–Pt(II) contacts are only observed in the crystal structure of a precursor complex. A key feature of the new complexes is their good solubility in common organic solvents, thanks to the presence of two hexyl chains that are attached to the terdentate ligands. 相似文献
109.
110.
M. Galinier C. P. Battarel B. Carpuat A. Faitrouni R. Hijazi S. Yactine 《Czechoslovak Journal of Physics》1971,21(4-5):579-582
The planar Hall effect in ferromagnetic thin films has been optimized with respect to composition dependence and geometric structure. Various devices can be realized with this effect, using the output voltage or the output current in a short circuited loop.This work was sponsored by Délégation Générate á la Recherche Scientifique et Technique.The authors thank R. Morille for the preparation of thin films. 相似文献