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131.
Jacopo Bellazzini Claudio Bonanno Gaetano Siciliano 《Mediterranean Journal of Mathematics》2009,6(3):347-366
We study the existence of vortices of the Klein-Gordon-Maxwell equations in the two dimensional case. In particular we find
sufficient conditions for the existence of vortices in the magneto-static case, i.e. when the electric potential f = 0{\phi = 0}. This result, due to the lack of suitable embedding theorems for the vector potential A is achieved with the help of a penalization method. 相似文献
132.
The problem of defining efficient strategies for partitioning the cavity surface in QM solvation procedures based on boundary
elements methods is considered here. The GEPOL procedure to get the cavity surface, and its partition into tesserae is adopted
as a starting point: a version with variable tesselation is presented. The procedure to build the new sphere tesselations
is described and several different options to select the surface partition have been implemented. The effects of the variation
of the surface partition on the free energy of solvation of several solutes are also presented. Two free energy of solvation
profiles evaluated with several different cavity partitions are analysed. We find that a radius-driven tesselation for every
sphere reduces the number and extension of the cavity artefacts.
Received: 6 August 1997 / Accepted: 23 October 1997 相似文献
133.
134.
Dr. Mauro Satta Dr. Anna Rita Casavola Dr. Antonella Cartoni Dr. Mattea Carmen Castrovilli Dr. Daniele Catone Dr. Jacopo Chiarinelli Prof. Stefano Borocci Dr. Lorenzo Avaldi Dr. Paola Bolognesi 《Chemphyschem》2021,22(23):2387-2391
Nitroimidazoles are a class of chemicals with a remarkable broad spectrum of applications from the production of explosives to the use as radiosensitizers in radiotherapy. The understanding of thedynamics of their fragmentation induced by ionizing sources is of fundamental interest. The goal of this work is to theoretically investigate the kinetic competition between the two most important decomposition channels of 2, 4 and 5-Nitroimidazole cations: the NO and NO2 losses. The calculated rate constants of the two processes are in very good agreement with the experimental Photoelectron-Photoion Coincidence (PEPICO) branching ratio. This study solves the intriguing and theoretically unexplained experimental observation that 2-Nitroimidazole, at variance with the other two regio-isomers is a source for only NO at low energies (<12.76 eV). This is a key point for biomedical application of the nitroimidazoles, because NO is the vasodilator that favors the reoxigenation of hypoxic tumor tissues. 相似文献
135.
136.
Ab initio SCF MO LCAO calculations with the 4-31G basis set on the ten most stable complexes involving H2O, HF, HC1, F– and Cl– have been examined in order to verify whether there is some evidence supporting the hypothesis that water can act as a catalyst for some nucleophilic substitution reactions performed in inert solvents with hydrogen halides as nucleophile agents (e.g. the formation of halohydrins from epoxides). Energetic considerations and an analysis of the electrostatic contribution to the reactivity of the H2O-HX adduct seem to support this hypothesis. 相似文献
137.
Patrizia N. Hanieh Jacopo Forte Chiara Di Meo Maria Grazia Ammendolia Elena Del Favero Laura Cant Federica Rinaldi Carlotta Marianecci Maria Carafa 《Molecules (Basel, Switzerland)》2021,26(11)
Hyaluronic acid (HA) is one of the most used biopolymers in the development of drug delivery systems, due to its biocompatibility, biodegradability, non-immunogenicity and intrinsic-targeting properties. HA specifically binds to CD44; this property combined to the EPR effect could provide an option for reinforced active tumor targeting by nanocarriers, improving drug uptake by the cancer cells via the HA-CD44 receptor-mediated endocytosis pathway. Moreover, HA can be easily chemically modified to tailor its physico-chemical properties in view of specific applications. The derivatization with cholesterol confers to HA an amphiphilic character, and then the ability of anchoring to niosomes. HA-Chol was then used to coat Span® or Tween® niosomes providing them with an intrinsic targeting shell. The nanocarrier physico-chemical properties were analyzed in terms of hydrodynamic diameter, ζ-potential, and bilayer structural features to evaluate the difference between naked and HA-coated niosomes. Niosomes stability was evaluated over time and in bovine serum. Moreover, interaction properties of HA-coated nanovesicles with model membranes, namely liposomes, were studied, to obtain insights on their interaction behavior with biological membranes in future experiments. The obtained coated systems showed good chemical physical features and represent a good opportunity to carry out active targeting strategies. 相似文献
138.
Scholes GD Curutchet C Mennucci B Cammi R Tomasi J 《The journal of physical chemistry. B》2007,111(25):6978-6982
The way that solvent (or host medium) modifies the rate of electronic energy transfer (EET) has eluded researchers for decades. By applying quantum chemical methods that account for the way solvent (in general any host medium including liquid, solid, or protein, etc.) responds to the interaction between transition densities, we quantify the solvent screening. We find that it attains a striking exponential attenuation at separations less than about 20 A, thus interpolating between the limits of no apparent screening and a significant attenuation of the EET rate. That observation reveals a previously unidentified contribution to the distance dependence of the EET rate. 相似文献
139.
Christian Silvio Pomelli Jacopo Tomasi Maurizio Cossi Vincenzo Barone 《Journal of computational chemistry》1999,20(16):1693-1701
A new computational strategy for the building of molecular cavities (named DefPol) has been linked to the most recent implementation of the polarizable continuum model (PCM) for the representation of solvent effects on physicochemical properties of large molecules. Free energies, analytical gradients, and Hessians can be computed in this framework in the rigid cavity approximation. Coupling DefPol cavities with a number of other recent improvements of the standard algorithm (e.g., effective use of symmetry, iterative procedures with linear scaling) significantly enlarges the dimensions of systems amenable to refined computations and strongly reduces the gap between computations for isolated molecules and in solution. © 1999 John Wiley & Sons, Inc. J Comput Chem 20: 1693–1701, 1999 相似文献
140.