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131.
In this article we show that for the homogenization of multiple integrals, the quasiconvexification of the cell formula is
different from the asymptotic formula in general. To this aim, we construct three examples in three different settings: the
homogenization of a discrete model, the homogenization of a composite material and the homogenization of a homogeneous material
on a perforated domain. 相似文献
132.
Yingjie Lan Michael O. Ball Itir Z. Karaesmen Jean X. Zhang Gloria X. Liu 《European Journal of Operational Research》2015
We investigate a single-leg airline revenue management problem where an airline has limited demand information and uncensored no-show information. To use such hybrid information for simultaneous overbooking and booking control decisions, we combine expected overbooking cost with revenue. Then we take a robust optimization approach with a regret-based criterion. While the criterion is defined on a myriad of possible demand scenarios, we show that only a small number of them are necessary to compute the objective. We also prove that nested booking control policies are optimal among all deterministic ones. We further develop an effective computational method to find the optimal policy and compare our policy to others proposed in the literature. 相似文献
133.
Marina Naldi Gloria Brusotti Gabriella Massolini Vincenza Andrisano Caterina Temporini Manuela Bartolini 《Molecules (Basel, Switzerland)》2021,26(14)
A combination of flash chromatography, solid phase extraction, high-performance liquid chromatography, and in vitro bioassays was used to isolate phytocomponents endowed with anticholinesterase activity in extract from Phyllanthus muellarianus. Phytocomponents responsible for the anti-cholinesterase activity of subfractions PMF1 and PMF4 were identified and re-assayed to confirm their activity. Magnoflorine was identified as an active phytocomponent from PMF1 while nitidine was isolated from PMF4. Magnoflorine was shown to be a selective inhibitor of human butyrylcholinesterase—hBChE (IC50 = 131 ± 9 μM and IC50 = 1120 ± 83 μM, for hBuChE and human acetylcholinesterase—hAChE, respectively), while nitidine showed comparable inhibitory potencies against both enzymes (IC50 = 6.68 ± 0.13 μM and IC50 = 5.31 ± 0.50 μM, for hBChE and hAChE, respectively). When compared with the commercial anti-Alzheimer drug galanthamine, nitidine was as potent as galanthamine against hAChE and one order of magnitude more potent against hBuChE. Furthermore, nitidine also showed significant, although weak, antiaggregating activity towards amyloid-β self-aggregation. 相似文献
134.
Cárdenas C Bidon-Chanal A Conejeros P Arenas G Marshall S Luque FJ 《Journal of computer-aided molecular design》2010,24(12):1035-1051
Knowledge of the 3D structure of the binding groove of major histocompatibility (MHC) molecules, which play a central role
in the immune response, is crucial to shed light into the details of peptide recognition and polymorphism. This work reports
molecular modeling studies aimed at providing 3D models for two class I and two class II MHC alleles from Salmo salar (Sasa), as the lack of experimental structures of fish MHC molecules represents a serious limitation to understand the specific
preferences for peptide binding. The reliability of the structural models built up using bioinformatic tools was explored
by means of molecular dynamics simulations of their complexes with representative peptides, and the energetics of the MHC-peptide
interaction was determined by combining molecular mechanics interaction energies and implicit continuum solvation calculations.
The structural models revealed the occurrence of notable differences in the nature of residues at specific positions in the
binding groove not only between human and Sasa MHC proteins, but also between different Sasa alleles. Those differences lead to distinct trends in the structural features that mediate the binding of peptides to both
class I and II MHC molecules, which are qualitatively reflected in the relative binding affinities. Overall, the structural
models presented here are a valuable starting point to explore the interactions between MHC receptors and pathogen-specific
interactions and to design vaccines against viral pathogens. 相似文献
135.
An enantioselective α-amination of aryl oxindoles catalyzed by a dimeric quinidine has been developed. The reaction is general, broad in substrate scope, and affords the desired products in good yields with good to excellent enantioselectivities. This study provides the first examples of a general organocatalytic method for the creation of nitrogen-containing, tetrasubstituted chiral centers at C(3) of various aryl oxindoles. Furthermore, new catalysts and insights into structural elements of the catalysts that significantly influence enantioselectivities are disclosed. 相似文献
136.
Joaquín García Gloria Subías Vera Cuartero Javier Herrero‐Martin 《Journal of synchrotron radiation》2010,17(3):386-392
Here the correlation between the chemical shift in X‐ray absorption spectroscopy, the geometrical structure and the formal valence state of the Mn atom in mixed‐valence manganites are discussed. It is shown that this empirical correlation can be reliably used to determine the formal valence of Mn, using either X‐ray absorption spectroscopy or resonant X‐ray scattering techniques. The difficulties in obtaining a reliable comparison between experimental XANES spectra and theoretical simulations on an absolute energy scale are revealed. It is concluded that the contributions from the electronic occupation and the local structure to the XANES spectra cannot be separated either experimentally or theoretically. In this way the geometrical and electronic structure of the Mn atom in mixed‐valence manganites cannot be described as a bimodal distribution of the formal integer Mn3+ and Mn4+ valence states corresponding to the undoped references. 相似文献
137.
Masaaki Ohba Dr. Ko Yoneda Gloria Agustí M. Carmen Muñoz Prof. Dr. Ana B. Gaspar Dr. José A. Real Prof. Dr. Mikio Yamasaki Dr. Hideo Ando Yoshihide Nakao Dr. Shigeyoshi Sakaki Prof. Dr. Susumu Kitagawa Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(26):4767-4771
The ins and outs of spin : Using the microporous coordination polymer {Fe(pz)[Pt(CN)4]} ( 1 , pz=pyrazine), incorporating spin‐crossover subunits, two‐directional magnetic chemo‐switching is achieved at room temperature. In situ magnetic measurements following guest vapor injection show that most guest molecules transform 1 from the low‐spin (LS) state to the high‐spin (HS) state, whereas CS2 uniquely causes the reverse HS‐to‐LS transition.
138.
Masaaki Ohba Ko Yoneda Gloria Agustí M.Carmen Muoz AnaB. Gaspar JosA. Real Mikio Yamasaki Hideo Ando Yoshihide Nakao Shigeyoshi Sakaki Susumu Kitagawa 《Angewandte Chemie (International ed. in English)》2009,48(26):4652-4652
Bidirectional chemo‐switching of magnetism occurs in a microporous coordination polymer containing spin‐crossover subunits, as described by M. Ohba, J. A. Real, S. Kitagawa, and co‐workers in their Communication on page 4767 ff. In situ magnetic measurements reveal that most guest molecules transform the framework spin state from diamagnetic low spin (red) to paramagnetic high spin (yellow), whereas the guest CS2 stabilizes the low‐spin state. These induced spin states are retained as a memory effect after the release of the guest.
139.
Laureano F. Escudero Araceli Garín María Merino Gloria Pérez 《Computational Management Science》2009,6(3):307-327
We present a model for optimizing a mean-risk function of the terminal wealth for a fixed income asset portfolio restructuring
with uncertainty in the interest rate path and the liabilities along a given time horizon. Some logical constraints are considered
to be satisfied by the assets portfolio. Uncertainty is represented by a scenario tree and is dealt with by a multistage stochastic
mixed 0-1 model with complete recourse. The problem is modelled as a splitting variable representation of the Deterministic
Equivalent Model for the stochastic model, where the 0-1 variables and the continuous variables appear at any stage. A Branch-and-Fix
Coordination approach for the multistage 0–1 program solving is proposed. Some computational experience is reported.
相似文献
140.
John?Kleppe Ruud?Hendrickx Peter?BormEmail author Ignacio?García-Jurado Gloria?Fiestras-Janeiro 《TOP》2010,18(2):481-492
This paper analyses the role of transfer payments and strategic contracting within two-person strategic form games with monetary
payoffs. First, it introduces the notion of transfer equilibrium as a strategy combination for which individual stability
can be supported by allowing the possibility of transfers of the induced payoffs. Clearly, Nash equilibria are transfer equilibria,
but under common regularity conditions the reverse is also true. This result typically does not hold for finite games without
the possibility of randomisation, and transfer equilibria for this particular class are studied in some detail. 相似文献