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Ali Maalaoui Vittorio Martino 《Calculus of Variations and Partial Differential Equations》2014,50(3-4):599-614
We consider a family of tight contact forms on the three-dimensional torus and we compute the relative Contact Homology by using the variational theory of critical points at infinity. We will also show local stability. 相似文献
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Daniel S. Covita Dimitrios F. Anagnostopoulos Hermann Fuhrmann Hubert Gorke Detlev Gotta Alexander Gruber Albert Hirtl Tomoichi Ishiwatari Paul Indelicato Thomas S. Jensen Eric-Olivier Le Bigot Valeri E. Markushin Michael Nekipelov Vladimir N. Pomerantsev Vladimir P. Popov Joaquim M. F. dos Santos Philipp Schmid Leopold M. Simons Marian Theisen Martino Trassinelli Joao F. C. A. Veloso Johann Zmeskal 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2018,72(4):72
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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
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Antonio Di Martino Pavel Kucharczyk Zdenka Capakova Petr Humpolicek Vladimir Sedlarik 《Journal of nanoparticle research》2017,19(2):71
In the presented work, amphiphilic nanoparticles based on chitosan and carboxy-enriched polylactic acid have been prepared to improve the stability of the pro-drug temozolomide in physiological media by encapsulation. The carrier, with a diameter in the range of 150–180 nm, was able to accommodate up to 800 μg of temozolomide per mg of polymer. The obtained formulation showed good stability in physiological condition and preparation media up to 1 month. Temozolomide loaded inside the carrier exhibited greater stability than the free drug, in particular in simulated physiological solution at pH 7.4 where the hydrolysis in the inactive metabolite was clearly delayed. CS-SPLA nanoparticles demonstrated a pH-dependent TMZ release kinetics with the opportunity to increase or decrease the rate. Mass spectroscopy, UV-Vis analysis, and in vitro cell tests confirmed the improvement in temozolomide stability and effectiveness when loaded into the polymeric carrier, in comparison with the free drug. 相似文献
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Marta Martino Andrea Salvadori Federico Lazzari Lorenzo Paoloni Surajit Nandi Giordano Mancini Vincenzo Barone Sergio Rampino 《Journal of computational chemistry》2020,41(13):1310-1323
The virtual-reality framework AVATAR (Advanced Virtual Approach to Topological Analysis of Reactivity) for the immersive exploration of potential-energy landscapes is presented. AVATAR is based on modern consumer-grade virtual-reality technology and builds on two key concepts: (a) the reduction of the dimensionality of the potential-energy surface to two process-tailored, physically meaningful generalized coordinates, and (b) the analogy between the evolution of a chemical process and a pathway through valleys (potential wells) and mountain passes (saddle points) of the associated potential energy landscape. Examples including the discovery of competitive reaction paths in simple A + BC collisional systems and the interconversion between conformers in ring-puckering motions of flexible rings highlight the innovation potential that augmented and virtual reality convey for teaching, training, and supporting research in chemistry. 相似文献
10.
A. P. Caricato A. Cretí A. Luches M. Lomascolo M. Martino R. Rella D. Valerini 《Laser Physics》2011,21(3):588-597
Various kinds of zinc oxide (ZnO) nanostructures, such as columns, pencils, hexagonal pyramids, hexagonal hierarchical structures,
as well as smooth and rough films, were grown by pulsed laser deposition using KrF and ArF excimer lasers, without use of
any catalyst. ZnO films were deposited at substrate temperatures from 500 to 700°C and oxygen background pressures of 1, 5,
50, and 100 Pa. Quite different morphologies of the deposited films were observed using scanning electron microscopy when
different laser wavelengths (248 or 193 nm) were used to ablate the bulk ZnO target. Photoluminescence studies were performed
at different temperatures (down to 7 K). The gas sensing properties of the different nanostructures were tested against low
concentrations of NO2. The variation in the photoluminescence emission of the films when exposed to NO2 was used as transduction mechanism to reveal the presence of the gas. The nanostructured films with higher surface-to-volume
ratio and higher total surface available for gas adsorption presented higher responses, detecting NO2 concentrations down to 3 ppm at room temperature. 相似文献