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141.
142.
Daniel E. Ceballos-Herrera Ismael Torres-Gómez Alejandro Martínez-Ríos José J. Sánchez-Mondragón 《Optical Review》2009,16(6):622-626
We present the spectral analysis of higher-order core mode resonances in a long period holey fiber grating induced mechanically
in an asymmetric holey fiber. Calculations based on a fast-Fourier transform mode solver shows that the mode resonances obtained
experimentally correspond to the odd- and even-LP1,1 core modes. Additionally, we analyze the twist and polarization response of these mode resonances in the long period holey
fiber grating. The results obtained in this work are of great importance in the design of new all-fiber optical devices that
involve couplings of higher order core modes in asymmetric holey fibers. 相似文献
143.
144.
Ismael G. Yero 《Applied mathematics and computation》2010,217(7):3571-3574
Let G = (V, E) be a connected graph. The distance between two vertices u, v ∈ V, denoted by d(u, v), is the length of a shortest u − v path in G. The distance between a vertex v ∈ V and a subset P ⊂ V is defined as , and it is denoted by d(v, P). An ordered partition {P1, P2, … , Pt} of vertices of a graph G, is a resolving partition of G, if all the distance vectors (d(v, P1), d(v, P2), … , d(v, Pt)) are different. The partition dimension of G, denoted by pd(G), is the minimum number of sets in any resolving partition of G. In this article we study the partition dimension of Cartesian product graphs. More precisely, we show that for all pairs of connected graphs G, H, pd(G × H) ? pd(G) + pd(H) and pd(G × H) ? pd(G) + dim(H), where dim(H) denotes the metric dimension of H. Consequently, we show that pd(G × H) ? dim(G) + dim(H) + 1. 相似文献
145.
Mirosława Różycka Ismael Coronado Katarzyna Brach Joanna Olesiak-Bańska Marek Samoć Mirosław Zarębski Jerzy Dobrucki Maciej Ptak Eva Weber Dr. Iryna Polishchuk Dr. Boaz Pokroy Jarosław Stolarski Prof. Andrzej Ożyhar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(55):12740-12750
The biological mediation of mineral formation (biomineralization) is realized through diverse organic macromolecules that guide this process in a spatial and temporal manner. Although the role of these molecules in biomineralization is being gradually revealed, the molecular basis of their regulatory function is still poorly understood. In this study, the incorporation and distribution of the model intrinsically disordered starmaker-like (Stm-l) protein, which is active in fish otoliths biomineralization, within calcium carbonate crystals, is revealed. Stm-l promotes crystal nucleation and anisotropic tailoring of crystal morphology. Intracrystalline incorporation of Stm-l protein unexpectedly results in shrinkage (and not expansion, as commonly described in biomineral and bioinspired crystals) of the crystal lattice volume, which is described herein, for the first time, for bioinspired mineralization. A ring pattern was observed in crystals grown for 48 h; this was composed of a protein-enriched region flanked by protein-depleted regions. It can be explained as a result of the Ostwald-like ripening process and intrinsic properties of Stm-l, and bears some analogy to the daily growth layers of the otolith. 相似文献
146.
Montse Lpez‐Martínez Manuel Lpez‐Ortiz Maria Elena Antinori Emilie Wientjes Alba Nin‐Hill Carme Rovira Roberta Croce Ismael Díez‐Prez Pau Gorostiza 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(38):13414-13418
The transport of electrons along photosynthetic and respiratory chains involves a series of enzymatic reactions that are coupled through redox mediators, including proteins and small molecules. The use of native and synthetic redox probes is key to understanding charge transport mechanisms and to the design of bioelectronic sensors and solar energy conversion devices. However, redox probes have limited tunability to exchange charge at the desired electrochemical potentials (energy levels) and at different protein sites. Herein, we take advantage of electrochemical scanning tunneling microscopy (ECSTM) to control the Fermi level and nanometric position of the ECSTM probe in order to study electron transport in individual photosystem I (PSI) complexes. Current–distance measurements at different potentiostatic conditions indicate that PSI supports long‐distance transport that is electrochemically gated near the redox potential of P700, with current extending farther under hole injection conditions. 相似文献
147.
Ahmed Khodairy Eman A. Ahmed Mohamed Ismael Khaled M. Mohamed Shymaa A. Thabet 《Journal of heterocyclic chemistry》2019,56(3):1055-1062
Some new triazole, thiadiazole, oxadiazole, thiazole, oxazole, and imidazole derivatives have been synthesized via the reaction of tramadol bearing a hydrazide, hydrazine carbodithioate, and/or acetic acid group with certain reagents. Molecular docking study had been carried out to demonstrate the reactivity of these synthetic compounds for interaction with Cytochrome P450 2D6 ( CYP2D6 ). 相似文献
148.
J. David Cabedo Semper Ismael Moya Clemente 《European Journal of Operational Research》2003,150(3):21
In this paper we put forward a new method to estimate value at risk (VaR), autoregressive conditional heteroskedastic (ARCH) factor, which combines multivariate analysis with ARCH models. Firstly, from a set of correlated portfolio risk factors, we derive a smaller uncorrelated risk factors set, by applying multivariate analysis. Secondly, we use ARCH schemes to model uncorrelated factors historical behaviour. Thirdly, we use the estimated models to predict future values for factors standard deviation. From them, VaR calculation is immediate. In this way, ARCH factor methodology overcomes the multivariate ARCH models drawbacks, which, in practice, make these unworkable for VaR calculation purposes. We apply the proposed methodology over a set of foreign exchange risk exposed portfolios, obtaining better results than those reached when J.P. Morgan’s Riskmetrics is used. 相似文献
149.
150.
Abad A Agulló C Cuñat AC de Alfonso I Navarro I Vera N 《Molecules (Basel, Switzerland)》2004,9(5):287-299
The commercially available monoterpene carvone has been efficiently converted into the tricyclo[3.2.1.0(2.7)]octane and bicyclo[3.2.1]octane systems characteristic of some biologically active compounds. The sequence used for this transformation involves as key features an intramolecular Diels-Alder reaction of a 5-vinyl-1,3-cyclohexadiene and a cyclopropane ring opening. 相似文献