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961.
Mathias Rafler 《Journal of Theoretical Probability》2013,26(4):1097-1116
Zessin (J. Contemp. Math. Anal. 44(1):36–44, 2009) constructed the so-called Pólya sum process via partial integration technique. This process shares some important properties with the Poisson process such as complete randomness and infinite divisibility. This work discusses H-sufficient statistics for the Pólya sum process as was done for the Poisson process by Nguyen and Zessin (Z. Wahrscheinlichkeitstheor. Verw. Geb. 37(3):191–200, 1976/77). 相似文献
962.
Nunes ET Bechara GH Saito KC Denardi SE Oliveira PR Mathias MI 《Micron (Oxford, England : 1993)》2005,36(5):437-447
The present study describes the morphology and ultrastructure of the salivary glands of semi-engorged females of the southern cattle-tick Rhipicephalus (Boophilus) microplus. The acini that compose these glands, at that specific feeding stage, show cells featuring degenerative process of the salivary glands, such as: vacuolated cytoplasm, condensed chromatin, fragmented nuclei, and presence of apoptotic bodies. In addition, the presence of microorganisms was detected, with morphology typical of protozoa, inside these organs. 相似文献
963.
Botana A Aguilar JA Nilsson M Morris GA 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,208(2):7063-278
Diffusion-ordered spectroscopy (DOSY) is a powerful NMR method for identifying compounds in mixtures. DOSY experiments are very demanding of spectral quality; even small deviations from expected behaviour in NMR signals can cause significant distortions in the diffusion domain. This is a particular problem when signals overlap, so it is very important to be able to acquire clean data with as little overlap as possible. DOSY experiments all suffer to a greater or lesser extent from multiplet phase distortions caused by J-modulation, requiring a trade-off between such distortions and gradient pulse width. Multiplet distortions increase spectral overlap and may cause unexpected and misleading apparent diffusion coefficients in DOSY spectra. These effects are described here and a simple and effective remedy, the addition of a 45° purging pulse immediately before the onset of acquisition to remove the unwanted anti-phase terms, is demonstrated. As well as affording significantly cleaner results, the new method allows much longer diffusion-encoding pulses to be used without problems from J-modulation, and hence greatly increases the range of molecular sizes that can be studied for coupled spin systems. The sensitivity loss is negligible and the added phase cycling is modest. The new method is illustrated for a widely-used general purpose DOSY pulse sequence, Oneshot. 相似文献
964.
Botana A Howe PW Caër V Morris GA Nilsson M 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,211(1):25-29
High Resolution Diffusion-ordered Spectroscopy (HR-DOSY) is a valuable tool for mixture analysis by NMR. It separates the signals from different components according to their diffusion behavior, and can provide exquisite diffusion resolution when there is no signal overlap. In HR-DOSY experiments on (1)H (by far the most common nucleus used for DOSY) there is frequent signal overlap that confuses interpretation. In contrast, a (13)C spectrum usually has little overlap, and is in this respect a much better option for a DOSY experiment. The low signal-to-noise ratio is a critical limiting factor, but with recent technical advances such as cryogenic probes this problem is now less acute. The most widely-used pulse sequences for (13)C DOSY perform diffusion encoding with (1)H, using a stimulated echo in which half of the signal is lost. This signal loss can be avoided by encoding diffusion with (13)C in a spin echo experiment such as the DEPTSE pulse sequence described here. 相似文献
965.
Rebecka Isaksson Jens Lindman Dr. Johan Wannberg Dr. Jessica Sallander Dr. Maria Backlund Dr. Dhaniel Baraldi Prof. Dr. Robert Widdop Prof. Dr. Mathias Hallberg Prof. Dr. Johan Åqvist Dr. Hugo Gutierrez de Teran Dr. Johan Gising Prof. Dr. Mats Larhed 《ChemistryOpen》2019,8(1):114-125
We here report on our continued studies of ligands binding to the promising drug target angiotensin II type 2 receptor (AT2R). Two series of compounds were synthesized and investigated. The first series explored the effects of adding small substituents to the phenyl ring of the known selective nonpeptide AT2R antagonist C38 , generating small but significant shifts in AT2R affinity. One compound in the first series was equipotent to C38 and showed similar kinetic solubility, and stability in both human and mouse liver microsomes. The second series was comprised of new bicyclic derivatives, amongst which one ligand exhibited a five-fold improved affinity to AT2R as compared to C38 . The majority of the compounds in the second series, including the most potent ligand, were inferior to C38 with regard to stability in both human and mouse microsomes. In contrast to our previously reported findings, ligands with shorter carbamate alkyl chains only demonstrated slightly improved stability in microsomes. Based on data presented herein, a more adequate, tentative model of the binding modes of ligand analogues to the prototype AT2R antagonist C38 is proposed, as deduced from docking redefined by molecular dynamic simulations. 相似文献
966.
967.
Mathias Beiglb?ck Johannes Muhle-Karbe Johannes Temme 《Mathematics and Financial Economics》2012,6(1):1-13
Consider an investor trading dynamically to maximize expected utility from terminal wealth. Our aim is to study the dependence
between her risk aversion and the distribution of the optimal terminal payoff. Economic intuition suggests that high risk
aversion leads to a rather concentrated distribution, whereas lower risk aversion results in a higher average payoff at the
expense of a more widespread distribution. Dybvig and Wang (J. Econ. Theory, 2011, to appear) find that this idea can indeed be turned into a rigorous mathematical statement in one-period models. More specifically,
they show that lower risk aversion leads to a payoff which is larger in terms of second order stochastic dominance. In the
present study, we extend their results to (weakly) complete continuous-time models. We also complement an ad-hoc counterexample
of Dybvig and Wang, by showing that these results are “fragile”, in the sense that they fail in essentially any model, if the latter is perturbed on a set of arbitrarily small probability. On the other hand, we establish that they hold
for power investors in models with (conditionally) independent increments. 相似文献
968.
For positive integers r>?, an r‐uniform hypergraph is called an ?‐cycle if there exists a cyclic ordering of its vertices such that each of its edges consists of r consecutive vertices, and such that every pair of consecutive edges (in the natural ordering of the edges) intersect in precisely ? vertices; such cycles are said to be linear when ?=1, and nonlinear when ?>1. We determine the sharp threshold for nonlinear Hamiltonian cycles and show that for all r>?>1, the threshold for the appearance of a Hamiltonian ?‐cycle in the random r‐uniform hypergraph on n vertices is sharp and given by for an explicitly specified function λ. This resolves several questions raised by Dudek and Frieze in 2011.10 相似文献
969.
Keith J. Flanagan Dr. Stefan S. R. Bernhard Dr. Shane Plunkett Prof. Dr. Mathias O. Senge 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):6941-6954
Previous studies by Desiraju and co-workers have implicated the acidic hydrogen atoms of cubane as a support network for hydrogen bonding groups. Herein we report a detailed structural analysis of all currently available 1,4-disubstituted cubane structures with an emphasis on how the cubane scaffold interacts in its solid-state environment. In this regard, the interactions between the cubane hydrogen atoms and acids, ester, halogens, ethynyl, nitrogenous groups, and other cubane scaffolds were cataloged. The goal of this study was to investigate the potential of cubane as a substitute for phenyl. This could be achieved by analyzing all contacts that are directed by the cubane hydrogen atoms in the X-ray crystal structures. As a result, we have established several new cubane interaction profiles, such as the catemer formation seen in esters, the preferences of halogen–hydrogen contacts over direct halogen bonding, and the stabilizing effects caused by the cubane hydrogen atoms interacting with ethynyl groups. These interaction profiles can then be used as a guide for designing cubane bioisosteres of known materials and drugs containing phenyl moieties. 相似文献