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991.
A ranking method assigns to every weighted directed graph a (weak) ordering of the nodes. In this paper we axiomatize the ranking method that ranks the nodes according to their outflow using four independent axioms. Besides the well-known axioms of anonymity and positive responsiveness we introduce outflow monotonicity – meaning that in pairwise comparison between two nodes, a node is not doing worse in case its own outflow does not decrease and the other node’s outflow does not increase – and order preservation – meaning that adding two weighted digraphs such that the pairwise ranking between two nodes is the same in both weighted digraphs, then this is also their pairwise ranking in the ‘sum’ weighted digraph. The outflow ranking method generalizes the ranking by outdegree for directed graphs, and therefore also generalizes the ranking by Copeland score for tournaments. 相似文献
992.
Sushko I Novotarskyi S Körner R Pandey AK Cherkasov A Li J Gramatica P Hansen K Schroeter T Müller KR Xi L Liu H Yao X Öberg T Hormozdiari F Dao P Sahinalp C Todeschini R Polishchuk P Artemenko A Kuz'min V Martin TM Young DM Fourches D Muratov E Tropsha A Baskin I Horvath D Marcou G Muller C Varnek A Prokopenko VV Tetko IV 《Journal of chemical information and modeling》2010,50(12):2094-2111
The estimation of accuracy and applicability of QSAR and QSPR models for biological and physicochemical properties represents a critical problem. The developed parameter of "distance to model" (DM) is defined as a metric of similarity between the training and test set compounds that have been subjected to QSAR/QSPR modeling. In our previous work, we demonstrated the utility and optimal performance of DM metrics that have been based on the standard deviation within an ensemble of QSAR models. The current study applies such analysis to 30 QSAR models for the Ames mutagenicity data set that were previously reported within the 2009 QSAR challenge. We demonstrate that the DMs based on an ensemble (consensus) model provide systematically better performance than other DMs. The presented approach identifies 30-60% of compounds having an accuracy of prediction similar to the interlaboratory accuracy of the Ames test, which is estimated to be 90%. Thus, the in silico predictions can be used to halve the cost of experimental measurements by providing a similar prediction accuracy. The developed model has been made publicly available at http://ochem.eu/models/1 . 相似文献
993.
Lakhdar Sibous Embarek Bentouhami Amor Ma?za Gilles M. Bouet Mustayeen Ahmed Khan 《Journal of solution chemistry》2010,39(4):511-521
The condensation of 2-hydroxybenzaldehyde or 2,4-dihydroxybenzaldehyde with 4,4′-diaminobiphenyl in absolute EtOH in a molar
ratio 2:1 gave, respectively, the Schiff base ligands H2L1 or H2L2. The bases served as tetradentate ligands to coordinate CoII, NiII and CdII chlorides, leading to complexes where the metal:ligand ratio is 2:1. All of the compounds were characterized by elemental
analysis, infrared, electronic and mass spectroscopy, 1H-n.m.r. and d.s.c. The cyclic voltammograms of the ligands and their complexes in DMF are discussed. 相似文献
994.
Paweł Zajdel Dr. Gaël Nomezine Nicolas Masurier Dr. Muriel Amblard Dr. Maciej Pawłowski Prof. Jean Martinez Prof. Gilles Subra Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(25):7547-7553
The design, synthesis, and potential application of the pipecolic linker is presented. This new versatile handle can immobilize primary, secondary, and aromatic amines, as well as alcohols, phenols, and hydrazides, on a solid support. Compared with other linkers, the anchoring step is easy and efficient. The release of final products from the resin proceeds upon acidic treatment with high purities. The pipecolic linker offers the promise of being using in peptide chemistry to produce peptides modified at the N and C terminus, peptidomimetics, as well as small organic molecules. 相似文献
995.
996.
Dr. Johannes Karges Shi Kuang Dr. Yih Ching Ong Prof. Hui Chao Dr. Gilles Gasser 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(1):362-370
During the last decades, photodynamic therapy (PDT), an approved medical technique, has received increasing attention to treat certain types of cancer. Despite recent improvements, the treatment of large tumors remains a major clinical challenge due to the low ability of the photosensitizer (PS) to penetrate a 3D cellular architecture and the low oxygen concentrations present in the tumor center. To mimic the conditions found in clinical tumors, exceptionally large 3D multicellular tumor spheroids (MCTSs) with a diameter of 800 μm were used in this work to test a series of new RuII polypyridine complexes as one-photon and two-photon PSs. These metal complexes were found to fully penetrate the 3D cellular architecture and to generate singlet oxygen in the hypoxic center upon light irradiation. While having no observed dark toxicity, the lead compound of this study showed an impressive phototoxicity upon clinically relevant one-photon (595 nm) or two-photon (800 nm) excitation with a full eradication of the hypoxic center of the MCTSs. Importantly, this efficacy was also demonstrated on mice bearing an adenocarcinomic human alveolar basal epithelial tumor. 相似文献
997.
Gilles Serre Philippe Lafon Xavier Gloerfelt Christophe Bailly 《Journal of computational physics》2012,231(15):5176-5194
Development of optimal reduced-order models for linearized Euler equations is investigated. Recent methods based on proper orthogonal decomposition (POD), applicable for high-order systems, are presented and compared. Particular attention is paid to the link between the choice of the projection and the efficiency of the reduced model. A stabilizing projection is introduced to induce a stable reduced-order model at finite time even if the energy of the physical model is growing. The proposed method is particularly well adapted for time-dependent hyperbolic systems and intrinsically skew-symmetric models. This paper also provides a common methodology to reliably reduce very large nonsymmetric physical problems. 相似文献
998.
Krystyna Baczko Hélène Fensterbank Bruno Berini Nadège Bordage Gilles Clavier Rachel Méallet‐Renault Chantal Larpent Emmanuel Allard 《Journal of polymer science. Part A, Polymer chemistry》2016,54(1):115-126
This work deals with the covalent coupling of azide‐functionalized polymeric nanoparticles as a reactive core and amino‐terminated PAMAM dendrons as a reactive shell. The nanoassemblies thereby obtained could be modified after the dendronization step by grafting an alkynyl Bodipy dye on the unreacted azide moieties. Only a few steps are required to attain nanoassemblies that could mimic dendrimers of high generation with sizes of nano‐objects beyond those of dendrimers. The structure of the nanoassemblies are composed of a polystyrene core, an inner shell including the Bodipy dyes along with the internal branches of the PAMAM, and the terminal amino groups from the outer shell. The dendritic shell acts as a protective layer that prevents NP from aggregation in a surfactant free aqueous solution. The nano‐objects display absorption and emission maxima above 500 nm with brightness that are the same order of magnitude than Qdots. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 115–126 相似文献
999.
Cellulose functionalization via high-energy irradiation-initiated grafting of glycidyl methacrylate and cyclodextrin immobilization 总被引:2,自引:0,他引:2
Gilles Desmet Erzsébet Takács László Wojnárovits Judit Borsa 《Radiation Physics and Chemistry》2011,80(12):1358-1362
Cotton-cellulose was functionalized using gamma-irradiation-induced grafting of glycidyl methacrylate (GMA) to obtain a hydrophobic cellulose derivative with epoxy groups suitable for further chemical modification. Two grafting techniques were applied. In pre-irradiation grafting (PIG) cellulose was irradiated in air and then immersed in a GMA monomer solution, whereas in simultaneous grafting (SG) cellulose was irradiated in an inert atmosphere in the presence of the monomer. PIG led to a more homogeneous fiber surface, while SG resulted in higher grafting yield but showed clear indications of some GMA-homopolymerization. Effects of the reaction parameters (grafting method, absorbed dose, monomer concentration, solvent composition) were evaluated by SEM, gravimetry (grafting yield) and FTIR spectroscopy. Water uptake of the cellulose decreased while adsorption of a pesticide molecule increased upon grafting. The adsorption was further enhanced by β-cyclodextrin immobilization during SG. This method can be applied to produce adsorbents from cellulose based agricultural wastes. 相似文献
1000.
Gilles Olive Gabriela A. Pompeu Torezan Christophe Blecker 《Comptes Rendus Chimie》2012,15(11-12):1037-1047
The enzymatic synthesis of esters is well documented in the literature. A number of parameters have been revised to optimize the operating conditions, in view of a more industrial approach. The experimental conditions presented here are now superior to those of literature and the yields of esters show 78% of fructose laurate. Analytical methods have been perfected and rapid methods (based on different TLC conditions depending on the desired information), accurate methods (based on HPLC) and several purification methods were developed. 相似文献