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71.
Matthieu Felsinger 《偏微分方程通讯》2013,38(9):1539-1573
Weak solutions to parabolic integro-differential operators of order α ∈ (α0, 2) are studied. Local a priori estimates of Hölder norms and a weak Harnack inequality are proved. These results are robust with respect to α↗2. In this sense, the presentation is an extension of Moser's result from [20]. 相似文献
72.
Etienne Boutin Min Wang John C. Lin Matthieu Mesnage Daniela Mendoza Benedikt Lassalle‐Kaiser Christopher Hahn Thomas F. Jaramillo Marc Robert 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(45):16318-16322
Conversion of CO2 into valuable molecules is a field of intensive investigation with the aim of developing scalable technologies for making fuels using renewable energy sources. While electrochemical reduction into CO and formate are approaching industrial maturity, a current challenge is obtaining more reduced products like methanol. However, literature on the matter is scarce, and even more for the use of molecular catalysts. Here, we demonstrate that cobalt phthalocyanine, a well‐known catalyst for the electrochemical conversion of CO2 to CO, can also catalyze the reaction from CO2 or CO to methanol in aqueous electrolytes at ambient conditions of temperature and pressure. The studies identify formaldehyde as a key intermediate and an unexpected pH effect on selectivity. This paves the way for establishing a sequential process where CO2 is first converted to CO which is subsequently used as a reactant to produce methanol. Under ideal conditions, the reaction shows a global Faradaic efficiency of 19.5 % and chemical selectivity of 7.5 %. 相似文献
73.
Matthieu Lecompte Christophe Dumouchel 《Particle & Particle Systems Characterization》2008,25(2):154-167
The three‐parameter, Generalized Gamma function solution of a recent MEF formulation used to derive liquid spray drop‐size distribution, is applied to sprays resulting from three different atomization processes. The objectives of these applications are to determine the sign of the parameters for which this function reports a more reliable fit and to further understand the parameter stability problem reported elsewhere. It is found that the lack of stability of the parameters is related to a characteristic feature of the mathematical function and appears for a series of spray drop‐size distributions with constant shape. For each situation analyzed in the present study, the Generalized Gamma function provides a very good fit with parameters that are either constant or correlated to the working conditions. As far as the sign of the parameters is concerned, the results show that the best formulation is a function of the spray and that it is impossible to know, a priori, which parameter sign will report the best fit. Finally, for one situation, it is found that the Generalized Gamma function allows extrapolation of drop sizes outside the measured values. All of the results converge to conclude that the three‐parameter Generalized Gamma function, which is identical to the well‐known Nukiyama‐Tanasawa distribution, accumulates valuable attributes to represent liquid spray drop‐size distributions. 相似文献
74.
“(Diphosphine)Nickel”‐Catalyzed Negishi Cross‐Coupling: An Experimental and Theoretical Study 下载免费PDF全文
Dr. Emmanuel Nicolas Alexia Ohleier Florian D'Accriscio Dr. Anne‐Frédérique Pécharman Dr. Matthieu Demange Dr. Philippe Ribagnac Dr. Jorge Ballester Dr. Corinne Gosmini Dr. Nicolas Mézailles 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7690-7694
The use of a strongly donating “(bis‐dialkylphosphine)Ni” fragment promotes the catalytic coupling of a large range of ArCl and ArZnCl derivatives under mild conditions. Stoichiometric mechanistic investigations and DFT calculations prove that a Ni0/NiII cycle is operative in this system. 相似文献
75.
Samia Amara Joël Toulc'Hoat Laure Timperman Agnès Biller Hervé Galiano Corinne Marcel Matthieu Ledigabel Prof. Mérièm Anouti 《Chemphyschem》2019,20(4):581-594
The development of a suitable functional electrolyte is urgently required for fast-charging and high-voltage alkali-ion (Li, Na, K) batteries as well as next-generation hybrids supercapacitors. Many recent works focused on an optimal selection of electrolytes for alkali-ion based systems and their electrochemical performance but the understanding of the fundamental aspect that explains their different behaviour is rare. Herein, we report a comparative study of transport properties for LiPF6, NaPF6, KPF6 in acetonitrile (AN) and a binary mixture of ethylene carbonate (EC), dimethyl carbonate (DMC): (EC/DMC : 1/1, weigh) through conductivities, densities and viscosities measurements in wide temperature domain. By application of the Stokes-Einstein, Nernst-Einstein, and Jones Dole equations, the effective ionic solvated radius of cation (reff), the ionic dissociation coefficient (αD) and structuring Jones Dole's parameters (A, B) for salt are calculated and discussed according to solvent or cation nature as a function of temperature. From the results, we demonstrate that better mobility of potassium can be explained by the nature of the ion-ion and ion-solvent interactions due to its polarizability. In the same time, the predominance of triple ions in the case of K+, is a disadvantage at high concentration. 相似文献
76.
77.
Dr. Matthieu Jouffroy Dr. Jongrock Kong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(9):2217-2221
Nucleophilic radical additions at innately electrophilic C(sp2) centers are perfectly suited for the direct functionalization of heterocycles. Using bench stable and commercially available alkyl oxamate and oxamic acid derivatives in combination with photoredox catalysis, a direct carbamoylation of heterocycles yielding amide functionalized pharmacophores in a single step is reported. The reaction conditions reported are compatible with structurally complex heterocyclic substrates of pharmaceutical interest. Notably, derivatives containing functional groups incompatible with standard amidation reactions, such as carboxylic acids and unprotected amines, were found to be amenable to this reaction paradigm. 相似文献
78.
Matthieu Maréchal 《Journal of Optimization Theory and Applications》2018,176(3):541-558
In this article, we study the metric subregularity of generalized equations using a new tool of nonsmooth analysis. We obtain a sufficient condition for a generalized equation to be metrically subregular, which is not a necessary condition for metric regularity, using a subtle adjustment of the Mordukhovich coderivative. We apply these results to the study of the metric subregularity in a Cournot duopoly game. 相似文献
79.
Manon Réau Florent Langenfeld Jean-François Zagury Matthieu Montes 《Journal of computer-aided molecular design》2018,32(1):231-238
The Drug Design Data Resource (D3R) Grand Challenges are blind contests organized to assess the state-of-the-art methods accuracy in predicting binding modes and relative binding free energies of experimentally validated ligands for a given target. The second stage of the D3R Grand Challenge 2 (GC2) was focused on ranking 102 compounds according to their predicted affinity for Farnesoid X Receptor. In this task, our workflow was ranked 5th out of the 77 submissions in the structure-based category. Our strategy consisted in (1) a combination of molecular docking using AutoDock 4.2 and manual edition of available structures for binding poses generation using SeeSAR, (2) the use of HYDE scoring for pose selection, and (3) a hierarchical ranking using HYDE and MM/GBSA. In this report, we detail our pose generation and ligands ranking protocols and provide guidelines to be used in a prospective computer aided drug design program. 相似文献
80.
Gagey N Emond M Neveu P Benbrahim C Goetz B Aujard I Baudin JB Jullien L 《Organic letters》2008,10(12):2341-2344
This paper evaluates a series of photolabile protecting groups with built-in fluorescence reporting. They rely on readily available o-acetoxyphenyl methyloxazolones as activated precursors. Alcohol substrates are easily caged. The resulting photoactivable esters exhibit large one- and two-photon uncaging cross sections. The alcohol substrates are quantitatively released in a 1:1 molar ratio with a strongly fluorescent coumarin coproduct that serves as a reporter to quantify substrate delivery. 相似文献