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991.
The aim of this paper is to discuss the main ideas of the Talagrand proof of the Parisi Ansatz for the free-energy of Mean
Field Spin Glasses with a physicist's approach. We consider the case of the spherical p-spin model, which has the following advantages: (1) the Parisi Ansatz takes the simple “one step replica symmetry breaking
form,” (2) the replica free-energy as a function of the order parameters is simple enough to allow for numerical maximization
with arbitrary precision. We present the essential ideas of the proof, we stress its connections with the theory of effective
potentials for glassy systems, and we reduce the technically more difficult part of the Talagrand's analysis to an explicit
evaluation of the solution of a variational problem. 相似文献
992.
Francesca Benevelli Yaroslav Z. Khimyak Jacek Klinowski 《Journal of inclusion phenomena and macrocyclic chemistry》2004,49(3-4):211-218
Solid-state NMR techniques are used to study the effect of theinclusion of toluene and benzene on the mobility ofp-tert-butylcalixarene. We attribute the great increase inhost mobility upon complexation to the lack of strongdirectional intermolecular interactions. The differences inthe behaviour of the host in the two complexes are explainedin terms of the steric effects of the guest methyl group. 相似文献
993.
P. Collet 《Journal of statistical physics》1998,90(5-6):1075-1105
We consider the development of instabilities of homogeneous stationary solutions of discrete-time lattice maps. Under some generic hypotheses we derive an amplitude equation which is the space-time-continuous Ginzburg–Landau equation. Using dynamical renormalization group methods, we control the accuracy of this approximation in a large ball of its basin of attraction. 相似文献
994.
995.
Francesca Spadavecchia Michele Ceotto Leonardo Lo Presti Chiara Aieta Iolanda Biraghi Daniela Meroni Silvia Ardizzone Giuseppe Cappelletti 《中国化学》2014,32(12):1195-1213
A state‐of‐the‐art overview of N‐dopant characterizations in nano‐TiO2 second‐generation photocatalysts is provided. The related literature is very rich and sometimes offers contrasting interpretations. Here we critically discuss up‐to‐date literature results and our own findings, as retrieved by several experimental (BET, HR‐TEM, XPS, DRS, HR‐XRPD, EXAFS, electrochemical tools) and theoretical (periodic DFT) techniques. Our intent is to pull together outcomes from very different and complementary sources to make an as much as possible coherent picture of the morphological, electrochemical and electronic properties of N‐TiO2 materials. It is commonly accepted that critical issues to be considered in the design of high‐performing N‐TiO2 photocatalysts are synthetic strategy, defect concentration and chemical nature of the lattice point defects. We focus on the latter two issues, with emphasis on sol‐gel prepared materials, according to the specific area of expertise of our group. The problem of the chemical nature of guest N species into the lattice is crucial, as substitutional (Ns) or interstitial (Ni) nitrogen place their valence states just above the valence band or deeper into the band gap. Overall, we show how synergism among experimental and theoretical techniques is decisive to disentangle structural, electronic and morphological effects in complex N‐doped TiO2 matrices. 相似文献
996.
The paper presents an optimization framework for dealing with morphing airfoils for helicopter rotor blades. With regard to the morphing strategy, a conformable camber line is considered to deal with variable flow conditions encountered in forward flight with the objective of increasing the aerodynamic performance on the advancing and retreating sides of the rotor. Another peculiarity of the method is that the optimal shape is sought to be minimally sensitive to uncertainty in the operating conditions. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
997.
Loretta Laureana del Mercato Marzia Maria Ferraro Francesca Baldassarre Serena Mancarella Valentina Greco Ross Rinaldi Stefano Leporatti 《Advances in colloid and interface science》2014
Polyelectrolyte multilayer (PEM) capsules engineered with active elements for targeting, labeling, sensing and delivery hold great promise for the controlled delivery of drugs and the development of new sensing platforms. PEM capsules composed of biodegradable polyelectrolytes are fabricated for intracellular delivery of encapsulated cargo (for example peptides, enzymes, DNA, and drugs) through gradual biodegradation of the shell components. PEM capsules with shells responsive to environmental or physical stimuli are exploited to control drug release. In the presence of appropriate triggers (e.g., pH variation or light irradiation) the pores of the multilayer shell are unlocked, leading to the controlled release of encapsulated cargos. By loading sensing elements in the capsules interior, PEM capsules sensitive to biological analytes, such as ions and metabolites, are assembled and used to detect analyte concentration changes in the surrounding environment. This Review aims to evaluate the current state of PEM capsules for drug delivery and sensing applications. 相似文献
998.
Combined Experimental and Computational Studies on the Physical and Chemical Properties of the Renewable Amide, 3‐Acetamido‐5‐acetylfuran 下载免费PDF全文
The pKa of 3‐acetamido‐5‐acetylfuran (3A5AF) was predicted to be in the range 18.5–21.5 by using the B3LYP/6‐311+G(2d,p) method and several amides as references. The experimental pKa value, 20.7, was determined through UV/Vis titrations. Its solubility was measured in methanol‐modified supercritical CO2 (mole fraction, 3.23×10?4, cloud points 40–80 °C) and it was shown to be less soluble than 5‐hydroxymethylfurfural (5‐HMF). Dimerization energies were calculated for 3A5AF and 5‐HMF to compare hydrogen bonding, as such interactions will affect their solubility. Infrared and 1H nuclear magnetic resonance spectra of 3A5AF samples support the existence of intermolecular hydrogen bonding. The highest occupied molecular orbital, lowest unoccupied molecular orbital, and electrostatic potential of 3A5AF were determined through molecular orbital calculations using B3LYP/6‐311+G(2d,p). The π–π* transition energy (time‐dependent density functional theory study) was compared with UV/Vis data. Calculated atomic charges were used in an attempt to predict the reactivity of 3A5AF. A reaction between 3A5AF and CH3MgBr was conducted. As 3A5AF is a recently developed renewable compound that has previously not been studied extensively, these studies will be helpful in designing future reactions and processes involving this molecule. 相似文献
999.
Rinaldo M. Colombo Francesca Marcellini 《Mathematical Methods in the Applied Sciences》2015,38(7):1292-1302
We present a traffic flow model consisting of a gluing between the Lighthill–Whitham and Richards macroscopic model with a first‐order microscopic following the leader model. The basic analytical properties of this model are investigated. Existence and uniqueness are proved, as well as the basic estimates on the dependence of solutions from the initial data. Moreover, numerical integrations show some qualitative features of the model, in particular the transfer of information among regions where the different models are used. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
1000.