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61.
Ivana Kraiselburd Laura Moyano Analía Carrau Josefina Tano Elena G. Orellano 《Photochemistry and photobiology》2017,93(3):666-674
Light is an important environmental signal for almost all living organisms. The light perception is achieved by photoreceptor proteins. As can be observed from the great number of bacterial genomes sequenced, plant pathogenic bacteria encode for a large number of photoreceptor proteins. The physiological implications of these photoreceptors are still poorly characterized. However, recent studies revealed the participation of these photosensory proteins in the pathogenic process. Here, we summarize what is known about these proteins and their role during the virulence process, concluding that the light environment modulates the plant–pathogen interaction. 相似文献
62.
Gonzalo Angulo Dr. Jakob Grilj Eric Vauthey Prof. Luis Serrano‐Andrés Prof. Òscar Rubio‐Pons Dr. Patrice Jacques Prof. 《Chemphyschem》2010,11(2):480-488
The experimental ultrafast photophysics of thioxanthone in several aprotic organic solvents at room temperature is presented, measured using femtosecond transient absorption together with high‐level ab initio CASPT2 calculations of the singlet‐ and triplet‐state manifolds in the gas phase, including computed state minima and conical intersections, transition energies, oscillator strengths, and spin–orbit coupling terms. The initially populated singlet ππ* state is shown to decay through internal conversion and intersystem crossing processes via intermediate nπ* singlet and triplet states, respectively. Two easily accessible conical intersections explain the favorable internal conversion rates and low fluorescence quantum yields in nonpolar media. The presence of a singlet–triplet crossing near the singlet ππ* minimum and the large spin–orbit coupling terms also rationalize the high intersystem crossing rates. A phenomenological kinetic scheme is proposed that accounts for the decrease in internal conversion and intersystem crossing (i.e. the very large experimental crescendo of the fluorescence quantum yield) with the increase of solvent polarity. 相似文献
63.
64.
Laura Parejo Dr. Mahdi Chaari Sara Santiago Dr. Gonzalo Guirado Prof. Francesc Teixidor Dr. Rosario Núñez Dr. Jordi Hernando 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(1):270-280
Icosahedral metallacarboranes are θ-shaped anionic molecules in which two icosahedra share one vertex that is a metal center. The most remarkable of these compounds is the anionic cobalt-based metallacarborane [Co(C2B9H11)2]−, whose oxidation-reduction processes occur via an outer sphere electron process. This, along with its low density negative charge, makes [Co(C2B9H11)2]− very appealing to participate in electron-transfer processes. In this work, [Co(C2B9H11)2]− is tethered to a perylenediimide dye to produce the first examples of switchable luminescent molecules and materials based on metallacarboranes. In particular, the electronic communication of [Co(C2B9H11)2]− with the appended chromophore unit in these compounds can be regulated upon application of redox stimuli, which allows the reversible modulation of the emitted fluorescence. As such, they behave as electrochemically-controlled fluorescent molecular switches in solution, which surpass the performance of previous systems based on conjugates of perylendiimides with ferrocene. Remarkably, they can form gels by treatment with appropriate mixtures of organic solvents, which result from the self-assembly of the cobaltabisdicarbollide-perylendiimide conjugates into 1D nanostructures. The interplay between dye π-stacking and metallacarborane electronic and steric interactions ultimately governs the supramolecular arrangement in these materials, which for one of the compounds prepared allows preserving the luminescent behavior in the gel state. 相似文献
65.
James T. Brewster II Apolonio Aguilar Gonzalo Anguera Hadiqa Zafar Matthew D. Moore 《Journal of Coordination Chemistry》2018,71(11-13):1808-1813
AbstractThe reaction between amethyrin and non-aqueous uranyl silylamide (UO2[N(SiMe3)2]2) under anaerobic conditions affords a bench-stable uranyl complex. UV–vis spectroscopy, cyclic voltammetry, as well as proton NMR spectroscopic analyses provide support for the conclusion that all six pyrrole subunits participate in coordination of the uranyl dication and that, upon complexation, the amethyrin-core undergoes a 2-electron oxidation to yield a formal 22 π-electron aromatic species. 相似文献
66.
A unified approach for the synthesis of (S)-(+)-sotalol and (R)-(?)-isoproterenol has been developed. The enantioselective Henry reaction of the appropriate aldehyde in the presence of a camphor-derived amino pyridine–Cu(II) complex was the key step of the synthesis. The reduction of the nitro group to give the corresponding amino alcohols followed by reductive alkylation of the amine provided the target products with high enantiomeric excesses. 相似文献
67.
68.
Gonzalo Contreras 《Journal of Geometric Analysis》1998,8(4):533-569
We study the regularity of the Hausdorff dimension of the harmonic class of a surface M of negative curvature as a function
of the riemannian metric. We prove that it is a Cr− 3 function of the metric in the Banach manifold of Cr riemannian metrics on M. We also prove regularity results for some asymptotic quantities associated to the Brownian motion
on M. 相似文献
69.
J.Hernández Mendez R.Carabias Martínez E.Rodriguez Gonzalo J.Perez Trancon 《Analytica chimica acta》1990
The amperometric determination of parathion in the presence of its metabolites paraoxon and p-nitrophenol in a flow-injection system is reported. The method is based on the measurement of the oxidation signal yielded by p-nitrophenol on hydrolysis of parathion in the presence of Pd(II) or Hg(II). The oxidation of the metabolite was preferred to its reduction as it avoids the removal of oxygen, which poses major problems in flow-through configurations. 相似文献
70.
Gonzalo Martínez‐García Verónica Serafín Lourdes Agüí Paloma Yáñez‐Sedeño José M. Pingarrón 《Electroanalysis》2015,27(5):1119-1126
An electrochemical immunosensor for ghrelin (GHRL) determination in saliva is reported. Anti‐GHRL was immobilized onto Protein G‐magnetic beads and a competitive immunoassay involving biotinylated GHRL and alkaline phosphatase‐streptavidin was implemented. Once conjugate was magnetically captured on a screen‐printed carbon electrode, GHRL quantization was accomplished by DPV of 1‐naphtol formed upon addition of 1‐naphtyl phosphate. A linear range between 10?3 and 103 ng/mL GHRL, and a LOD of 7 pg/mL, much smaller than those from commercial ELISA kits, were found. The usefulness of the immunosensor was demonstrated by analyzing human saliva spiked with GHRL at 0.01, 0.1, 1 and 10 ng/mL. 相似文献