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81.
82.
Spin-1 Blume-Capel model with longitudinal random crystal and transverse magnetic fields:A mean-field approach 下载免费PDF全文
Erhan Albayrak 《中国物理 B》2013,(7):494-498
The spin-1 Blume-Capel model with transverse and longitudinal external magnetic fields h, in addition to a longitudinal random crystal field D, is studied in the mean-field approximation. It is assumed that the crystal field is either turned on with probability p or turned off with probability 1 p on the sites of a square lattice. Phase diagrams are then calculated on the reduced temperature crystal field planes for given values of γ=Ω/J and p at zero h. Thus, the effect of changing γ and p are illustrated on the phase diagrams in great detail and interesting results are observed. 相似文献
83.
High‐molecular‐weight (co)polymers of trimethylene carbonate and D ,L ‐lactide are efficiently crosslinked using PETA during gamma irradiation. Form‐stable networks with gel contents of 86 ± 5 to 96 ± 1 are obtained from non‐crystalline (co)polymers. Glass transition temperatures and elastic moduli of the networks can be varied by adjusting the copolymer composition. The PETA‐containing (co)polymer networks are not cytotoxic. Upon incubation in macrophage cultures for 14 d, all (co)polymer films and PETA‐containing network films erode to varying extents, showing that these materials can be degraded by cell‐mediated erosion processes. This method is very useful for the facile preparation of TMC‐ and DLLA‐containing form‐stable networks from high‐molecular‐weight polymers.
84.
Relying on the stochastic analysis tools developed in Bayraktar and Yao (2011) [1], we solve the optimal stopping problems for non-linear expectations. 相似文献
85.
We develop a theory for solving continuous time optimal stopping problems for non-linear expectations. Our motivation is to consider problems in which the stopper uses risk measures to evaluate future rewards. Our development is presented in two parts. In the first part, we will develop the stochastic analysis tools that will be essential in solving the optimal stopping problems, which will be presented in Bayraktar and Yao (2011) [1]. 相似文献
86.
Erhan Albayrak 《Phase Transitions》2013,86(7):541-550
The distinct hysteresis loops (HLs) of ferromagnetic/antiferromagnetic (FM/AFM) two-layer Bethe lattice with the Ising spins of the top layer having only FM interactions and the bottom ones having only AFM interactions with the interlayer coupling is either FM or AFM type are studied by using a pairwise approach. The sublattice magnetizations are studied by increasing and decreasing the external magnetic field (H) to obtain the HLs. The shapes of the HLs are strongly dependent on the competitions among the system parameters and on the phase configurations. The HLs are formed only when the AFM-type interactions are involved. The small loops of hysteresis are also formed because of the reentrant behavior in the FM region. 相似文献
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Cusido J Battal M Deniz E Yildiz I Sortino S Raymo FM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(33):10399-10407
We designed a supramolecular strategy to modulate fluorescence in water under optical control. It is based on the entrapment of fluorophore-photochrome dyads within the hydrophobic interior of an amphiphilic polymer. The polymeric envelope around the dyads protects them from the aqueous environment, while imposing hydrophilic character on the overall supramolecular construct. In the resulting assemblies, the photochromic component can be operated reversibly on a microsecond timescale under the influence of ultraviolet stimulations. In turn, the reversible transformations control the emission intensity of the adjacent fluorophore. As a result, the fluorescence of such nanostructured constructs can be photomodulated for hundreds of cycles in water with microsecond switching speeds. Thus, our protocol for fast fluorescence switching in aqueous solutions can eventually lead to the realization of functional probes for the investigation of biological samples. 相似文献
89.
The paper presents a tight Lagrangian bound and an efficient dual heuristic for the flow interception problem. The proposed Lagrangian relaxation decomposes the problem into two subproblems that are easy to solve. Information from one of the subproblems is used within a dual heuristic to construct feasible solutions and is used to generate valid cuts that strengthen the relaxation. Both the heuristic and the relaxation are integrated into a cutting plane method where the Lagrangian bound is calculated using a subgradient algorithm. In the course of the algorithm, a valid cut is added and integrated efficiently in the second subproblem and is updated whenever the heuristic solution improves. The algorithm is tested on randomly generated test problems with up to 500 vertices, 12,483 paths, and 43 facilities. The algorithm finds a proven optimal solution in more than 75% of the cases, while the feasible solution is on average within 0.06% from the upper bound. 相似文献
90.
Tobias Baumann Matthias Hauf Fabian Schildhauer Katharina B. Eberl Patrick M. Durkin Erhan Deniz Jan G. Lffler Carlos G. Acevedo‐Rocha Jelena Jaric Berta M. Martins Holger Dobbek Jens Bredenbeck Nediljko Budisa 《Angewandte Chemie (International ed. in English)》2019,58(9):2899-2903
Allosteric information transfer in proteins has been linked to distinct vibrational energy transfer (VET) pathways in a number of theoretical studies. Experimental evidence for such pathways, however, is sparse because site‐selective injection of vibrational energy into a protein, that is, localized heating, is required for their investigation. Here, we solved this problem by the site‐specific incorporation of the non‐canonical amino acid β‐(1‐azulenyl)‐l ‐alanine (AzAla) through genetic code expansion. As an exception to Kasha's rule, AzAla undergoes ultrafast internal conversion and heating after S1 excitation while upon S2 excitation, it serves as a fluorescent label. We equipped PDZ3, a protein interaction domain of postsynaptic density protein 95, with this ultrafast heater at two distinct positions. We indeed observed VET from the incorporation sites in the protein to a bound peptide ligand on the picosecond timescale by ultrafast IR spectroscopy. This approach based on genetically encoded AzAla paves the way for detailed studies of VET and its role in a wide range of proteins. 相似文献