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151.
152.
Navarrete-Astorga Elena Rodríguez-Moreno Jorge Dalchiele Enrique A. Schrebler Ricardo Leyton Patricio Ramos-Barrado José R. Martín Francisco 《Journal of Solid State Electrochemistry》2017,21(5):1431-1444
Journal of Solid State Electrochemistry - A feasibility study of the synthesis of gel polymer electrolytes based in methyl methacrylate (MMA) and 1-vinyl-2-pyrrolidone (VP) using [HEMIm][BF4] as... 相似文献
153.
Ricardo Abreu-Blaya Juan Bory-Reyes Richard Delanghe Frank Sommen 《Complex Analysis and Operator Theory》2012,6(2):341-357
In this paper, using the ring structure of the space of circulant (2 × 2)-matrix, we characterize the dual of the (Fréchet)
space of germs of left Hermitean monogenic matrix functions in a compact set
_boxclose_boxclose_boxclose_boxclose_boxclose_boxclose_boxclose_boxclose R^2n{{\bf E}\subset\mathbb R^{2n}}. As an application we describe the dual space of the so-called h-monogenic functions satisfying simultaneously two Dirac type equations. 相似文献
154.
E. Miranda C. Garzón C.S. Martínez-Cisneros J. Alonso J. García-García 《Journal of Electrostatics》2012,70(3):264-268
The spatial distribution of tiny holes in sheet materials generated by means of electrical discharges is investigated using spatial statistics techniques. It is shown that whereas the holes appear to be randomly distributed according to a Poisson point pattern, there is in fact a small region around each hole in which the generation of a new one is statistically inhibited as a consequence of the lower impedance path offered by the already made hole. The resulting pattern is known in spatial statistics as a point process with a soft-core inhibition potential, which can be characterized using the pair correlation function. 相似文献
155.
Jorge L. Flores Gastón A. Ayubi Julia R. Alonso Ariel Fernández J. Matías Di Martino José A. Ferrari 《Optik》2013
We present a hybrid method for segmentation of intensity images, which combines an optical contouring technique and digital algorithms for linking edge points or image segmentation. In a first stage, the digital image to be processed is displayed in a twisted-nematic liquid-crystal display (LCD), which is placed between a polarizer–analyzer pair at 45 deg (instead of 90 deg as occurs in standard LCDs). It is not difficult to demonstrate that the proposed setup produces a resultant image with very pronounced dark contours at middle intensity. After the optical preprocessing, two different digital algorithms are applied: an edge linking algorithm (modified chain code) and a simple thresholding technique for image segmentation. The proposed procedure works well with monochromatic and color images. The method could be useful as a robust technique for segmentation of large images in real-time, which presents potential applications in medical and biological imaging. 相似文献
156.
157.
Luís Antônio Dantas Silva Fernanda Vieira Teixeira Raphael Caixeta Serpa Najla Locatelli Esteves Rayane Ramos dos Santos Eliana Martins Lima Marcílio Sérgio Soares da Cunha-Filho Adriano Antunes de Souza Araújo Stephânia Fleury Taveira Ricardo Neves Marreto 《Journal of Thermal Analysis and Calorimetry》2016,123(3):2337-2344
158.
Dr. Ricardo Pérez de Tudela Prof. Dominik Marx 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(52):11955-11959
Acid dissociation, and thus liberation of excess protons in small water droplets, impacts on diverse fields such as interstellar, atmospheric or environmental chemistry. At cryogenic temperatures below 1 K, it is now well established that as few as four water molecules suffice to dissociate the generic strong acid HCl, yet temperature-driven recombination sets in simply upon heating that cluster. Here, the fundamental question is posed of how many more water molecules are required to stabilize a hydrated excess proton at room temperature. Ab initio path integral simulations disclose that not five, but six water molecules are needed at 300 K to allow for HCl dissociation independently from nuclear quantum effects. In order to provide the molecular underpinnings of these observations, the classical and quantum free energy profiles were decomposed along the dissociation coordinate in terms of the corresponding internal energy and entropy profiles. What decides in the end about acid dissociation, and thus ion pair formation, in a specific microsolvated water cluster at room temperature is found to be a fierce competition between classical configurational entropy and internal energy, where the former stabilizes the undissociated state whereas the latter favors dissociation. It is expected that these are generic findings with broad implications on acid–base chemistry depending on temperature in small water assemblies. 相似文献
159.
Reversible Activation of Water by an Air- and Moisture-Stable Frustrated Rhodium Nitrogen Lewis Pair
Dr. María Carmona Dr. Joaquina Ferrer Dr. Ricardo Rodríguez Dr. Vincenzo Passarelli Prof. Dr. Fernando J. Lahoz Dr. Pilar García-Orduña Dr. Laura Cañadillas-Delgado Prof. Dr. Daniel Carmona 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(60):13665-13670
[Cp*Rh(κ3N,N′,P- L )][SbF6] (Cp*=C5Me5), bearing a guanidine-derived phosphano ligand L , behaves as a “dormant” frustrated Lewis pair and activates H2 and H2O in a reversible manner. When D2O is employed, a facile H/D exchange at the Cp* ring takes place through sequential C(sp3)−H bond activation. 相似文献
160.