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111.
We present a new method for solving numerically the equations associated with solvation continuum models, which also works
when the solvent is an anisotropic dielectric or an ionic solution. This method is based on the integral equation formalism.
Its theoretical background is set up and some numerical results for simple systems are given. This method is much more effective
than three‐dimensional methods used so far, like finite elements or finite differences, in terms of both numerical accuracy
and computational costs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
112.
Mennucci B Caricato M Ingrosso F Cappelli C Cammi R Tomasi J Scalmani G Frisch MJ 《The journal of physical chemistry. B》2008,112(2):414-423
The spectroscopic behavior of 6-propionyl-2-(N,N-dimethyl)aminonaphthalene (PRODAN) is investigated in different environments, ranging from homogeneous solutions of different polarities to diffuse interfaces mimicking membranes. The variety of experimental data as well as computational results present in the literature still do not clarify the nature of the emission process; in particular, it is not well-established whether fluorescence in such a molecule occurs from a planar or from a twisted intramolecular charge transfer state. The first part of the work is thus devoted to better understand how the electronic transition processes occur in homogeneous solvents. The effect of the medium polarity as well as the hydrogen bond formation are studied. In the second part of the paper, a first attempt to interpret the experimental results of PRODAN in unilamellar vesicles is carried out. The complexity of the still-open questions about the photophysics of PRODAN has prompted us to base the study on quantum-mechanical calculations performed at various levels of theory, namely, DFT, TDDFT, CIS, and SAC-CI, and to include the effects of the environment in a self-consistent way. This is achieved by using the integral equation formalism version of the polarizable continuum model (IEFPCM). IEFPCM is a quite versatile approach, being able to treat equilibrium and nonequilibrium solvation in both homogeneous and heterogeneous media. 相似文献
113.
114.
Combined mass quantitation and phenotyping of intact extracellular vesicles by a microarray platform
Paola Gagni Marina Cretich Luisa Benussi Elisa Tonoli Miriam Ciani Roberta Ghidoni Benedetta Santini Elisabetta Galbiati Davide Prosperi Marcella Chiari 《Analytica chimica acta》2016
The interest towards extracellular vesicles (EVs) has grown exponentially over the last few years; being involved in intercellular communication and serving as reservoirs for biomarkers for tumors, they have a great potential for liquid biopsy development, possibly replacing many costly and invasive tissue biopsies. 相似文献
115.
116.
117.
Alessandro Biancardi Roberto Cammi Chiara Cappelli Benedetta Mennucci Jacopo Tomasi 《Theoretical chemistry accounts》2012,131(3):1157-10
In this paper, a computational strategy, based on DFT calculations at the M06-2X level, combined with the polarizable continuum
model, the Hessian matrix reconstruction method and the Partial hessian vibrational approach is applied to evaluate inter-
and intra-layer vibrational couplings between hydrogen bonded and stacked DNA base pairs. The present work demonstrates that
this computational scheme can effectively predict and interpret the vibrational couplings of nucleic acids in solution. The
effect of the environment described in a cluster or in a continuum manner is necessary in order to improve the agreement with
the experimental values. 相似文献
118.
Benedetta Cerbai Roberto Solaro Emo Chiellini 《Journal of polymer science. Part A, Polymer chemistry》2008,46(7):2459-2476
This work aimed at the development of bioactive polymeric materials to be used for targeted drug delivery and tissue engineering applications. The proposed strategy was based on the design of macromolecular systems whose functionality can be easily modified. Polyesters containing side‐chain end capped by primary hydroxyl groups were synthesized by polyaddition of oxetanes and carboxylic anhydrides catalyzed by quaternary onium salts. The polyaddition of bis(oxetane) with different dicarboxylic acids was also investigated. In all cases, oxetane monomers contained one hydroxyl group either free or protected by a benzyl group. The polymer yield and molecular weight were relatively high when aromatic anhydrides were used. In all other cases, low conversions or no polymerization at all were obtained. In a parallel research line, several alkanols were successfully employed to synthesize different α,β′,β‐trisubstituted‐β‐lactones. These monomers were prepared in five steps starting from diethyl oxalpropionate according to established synthetic routes. Final yields depended on both preparation method and side‐chain structure. By using quaternary ammonium salts as catalysts, the synthesized functional lactones underwent anionic ring opening polymerization leading to the corresponding homopolymers and copolymers in fairly good yields. The prepared polymeric materials were extensively characterized by spectroscopic techniques, size exclusion chromatography, and thermal analysis. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2459–2476, 2008 相似文献
119.
G Pizzoli MG Lobello B Carlotti F Elisei MK Nazeeruddin G Vitillaro F De Angelis 《Dalton transactions (Cambridge, England : 2003)》2012,41(38):11841-11848
We report a combined spectro-photometric and computational investigation of the acid-base equilibria of the N3 solar cell sensitizer [Ru(dcbpyH(2))(2)(NCS)(2)] (dcbpyH(2) = 4,4'-dicarboxyl-2,2' bipyridine) in aqueous/ethanol solutions. The absorption spectra of N3 recorded at various pH values were analyzed by Single Value Decomposition techniques, followed by Global Fitting procedures, allowing us to identify four separate acid-base equilibria and their corresponding ground state pK(a) values. DFT/TDDFT calculations were performed for the N3 dye in solution, investigating the possible relevant species obtained by sequential deprotonation of the four dye carboxylic groups. TDDFT excited state calculations provided UV-vis absorption spectra which nicely agree with the experimental spectral shapes at various pH values. The calculated pK(a) values are also in good agreement with experimental data, within <1 pK(a) unit. Based on the calculated energy differences a tentative assignment of the N3 deprotonation pathway is reported. 相似文献
120.
Denis Bonheure Benedetta Noris Tobias Weth 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2012
We study the existence of positive increasing radial solutions for superlinear Neumann problems in the ball. We do not impose any growth condition on the nonlinearity at infinity and our assumptions allow for interactions with the spectrum. In our approach we use both topological and variational arguments, and we overcome the lack of compactness by considering the cone of nonnegative, nondecreasing radial functions of H1(B). 相似文献