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851.
A systematic study of the magnetic properties by ion beam sputter-deposition system, was conducted in conjunction with the structure of FePt/FeMn multilayers fabricated onto MgO(0 0 1) substrates. Both parallel and perpendicular exchange biases were observed in the multilayers and were found to decrease drastically, as the deposition temperature is higher than 350 °C, which is evidently due to the interdiffusion at the interface. The thickness dependence study shows that the perpendicular magnetic anisotropy observed in the multilayers originates from surface anisotropy, being consistent with the decrease of perpendicular magnetic anisotropy as the deposition temperature is increased. The difference between parallel and perpendicular blocking temperatures that was clearly observed, is possibly due to the spin canting out of plane at the interface. 相似文献
852.
Takao Fukui 《General Relativity and Gravitation》2006,38(2):311-324
The magnitude-redshift test is applied to cosmological models in extended theories of gravity containing extra terms in the
Lagrangian which give rise to an evolving dark-energy component. Two classes of models are considered: one based on generalized
scalar-tensor theory and the other on curvature corrections to the metric tensor. Results are compared to recent observational
data of Type Ia supernovae. The predictions of both kinds of models may provide better fits to the data depending on dimensionless
free parameters of order ∼ 0.01−0.1. 相似文献
853.
Thet‐Thet‐Lwin Tohoru Takeda Jin Wu Naoki Sunaguchi Takeshi Murakami Satoshi Mouri Seita Nasukawa Qingkai Huo Tetsuya Yuasa Kazuyuki Hyodo Takao Akatsuka 《Journal of synchrotron radiation》2007,14(1):158-162
Fluorescent X‐ray computed tomography (FXCT) using synchrotron radiation reveals the cross‐sectional distribution of specific elements in biomedical objects. The aim of this study was to investigate the feasibility of FXCT imaging to assess the myocardial metabolic state quantitatively. Hearts labelled with non‐radioactive iodine myocardial fatty acid agent 15‐p‐(iodophenyl)‐3‐methylpentadecanoic acid (BMIPP) from cardiomyopathic and normal hamsters were imaged. FXCT images were compared with optical microscope images. Myocardial fatty acid metabolism enhanced with BMIPP was clearly depicted by FXCT, which showed an almost homogeneous image for normal and a heterogeneous image for cardiomyopathic hearts. Morphological structures of the heart such as the left ventricle and myocardial wall were also visualized by FXCT. Optical microscopy showed no fibrosis in normal and slight interstitial fibrosis in cardiomyopathic hearts. In the case of cardiomyopathy, the area of significantly reduced BMIPP uptake was 39% in the short axis of the mid‐left ventricle in the FXCT image, whereas a slight interstitial fibrosis of around 12% was recognized by optical microscopy for the same slice. This result indicated that reduced BMIPP uptake was caused by the myocardial fatty acid metabolic abnormality, not by the fibrosis in cardiomyopathy. Thus, FXCT images might be used to assess the quantitative metabolic analysis in small animal models of heart diseases. 相似文献
854.
Our aim in this paper is to deal with integrability of maximal functions for generalized Lebesgue spaces with variable exponent. Our exponent approaches 1 on some part of the domain, and hence the integrability depends on the shape of that part and the speed of the exponent approaching 1. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
855.
856.
A Periodic Mesoporous Organosilica‐Based Donor–Acceptor System for Photocatalytic Hydrogen Evolution
Masataka Ohashi Dr. Masao Aoki Dr. Ken‐ichi Yamanaka Kiyotaka Nakajima Dr. Tetsu Ohsuna Dr. Takao Tani Dr. Shinji Inagaki Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(47):13041-13046
A new solid‐sate donor–acceptor system based on periodic mesoporous organosilica (PMO) has been constructed. Viologen (Vio) was covalently attached to the framework of a biphenyl (Bp)‐bridged PMO. The diffuse reflectance spectrum showed the formation of charge‐transfer (CT) complexes of Bp in the framework with Vio in the mesochannels. The transient absorption spectra upon excitation of the CT complexes displayed two absorption bands due to radical cations of Bp and Vio species, which indicated electron transfer from Bp to Vio. The absorption bands slowly decayed with a half‐decay period of approximately 10 μs but maintained the spectral shape, thereby suggesting persistent charge separation followed by recombination. To utilize the charge separation for photocatalysis, Vio–Bp–PMO was loaded with platinum and its photocatalytic performance was tested. The catalyst successfully evolved hydrogen with excitation of the CT complexes in the presence of a sacrificial agent. In contrast, reference catalysts without either Bp–PMO or Vio gave no or little hydrogen generation, respectively. In addition, a homogeneous solution system of Bp molecules, methylviologen, and colloidal platinum also evolved no hydrogen, possibly due to a weaker electron‐donating feature of molecular Bp than that of densely packed Bp in Bp–PMO. These results indicated that densely packed Bp and Vio are essential for hydrogen evolution in this system and demonstrated the potential of PMO as the basis for donor–acceptor systems suitable for photocatalysis. 相似文献
857.
A. Świtaj-Zawadka P. Konieczka J. F. Biernat Y. Takao K. Mita S. Komar M. Wesołowski A. Przyjazny J. Namieśnik 《Journal of Thermal Analysis and Calorimetry》2006,86(2):531-536
Reference materials are used in every laboratory
in order to assure the appropriate quality of analytical results. The production
of reference materials is not an easy task especially in the case of gaseous,
toxic and malodorous compounds. Thermal decomposition of immobilized compounds
is a convenient way for the generation of those kinds of mixtures. Temperature
is an important variable in this process. In this case, thermoanalytical techniques
(thermogravimetry and differential scanning calorimetry (TG-DSC)) and scanning
electron microscopy (SEM) were used for checking the temperature range which
had been previously determined using thermal desorber-gas chromatograph-flame
ionization detector (TD-GC-FID) system. 相似文献
858.
Kiyoshi Kanamura Terutaka Nagashima Takao Umegaki 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1507-1511
The sulfuric acid treatment on steel manufacture slag (SMS) was performed to recover P resource. P element in SMS was successfully removed. Final products were a solid of CaSO 4 /SiO 2 and a solution containing PO 4 3 m , Fe, Al, Mg, and Mn. 相似文献
859.
Akio Toshimitsu Chitaru Hirosawa Katsuhiro Nakano Takao Mukai Kohei Tamao 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):355-356
A new chiral pool method is developed starting from readily available chiral oxiranes, the key step being the substitution reaction through the anchimeric assistance of the arylthio and arylseleno group. The overall transformation is the introduction of nucleopiles into the chiral carbon of the oxiranes with retention of the configuration. 相似文献
860.
Akira Hasegawa Takao Nagahama Hitoshi Ohki Makoto Kiso 《Journal of carbohydrate chemistry》2013,32(6):699-714
Abstract A stereocontrolled, facile total synthesis of ganglioside GM2 is described. Coupling of 2- (trimethylsilyl)ethyl O-(2,6-di-O-benzyl-(β-D-galactopyranosyl)-(1→4)-2,3,6-tri-O-benzyl-β-D-glucopyranoside (2), prepared from 2-(trimethylsilyl)ethyl β-lactoside (1) by selective 3′,4′-O-isopropylidenation, O-benzylation, and subsequent removal of the isopropylidene group, with methyl (methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy -2-thio-D-glycero-D-galacto -2-nonulopyranosid)onate (4) using N-iodosuccini-midc (NIS), gave the trisaccharide (5), which on condensation with methyl 6-O-benzoyl -2-dcoxy-3,4-O-isopropylidene-2-phthalimido-l-thio-β-D-galactopyranoside (11), gave the protected ganglioside GM2 oligosaccharide 12. Compound 12 was transformed, via O-deisopropylidenation, O-acetylation, removal of the phthaloyl group, N-acetylation, removal of the benzyl groups followed by (O-acetylation, selective removal of the 2-(rximethylsilyl)ethyl group, and subsequent imidate formation, into the final glycosyl donor 19. Glycosylation of (2S,3R,4E)-2-azido-3-O-benzoyl-4-octadecene-l,3-diol (20) with the α-trichloroacetimidate 19 gave the β-glycoside 21, which on channeling through selective reduction of the azide group, coupling of the amino group with octadecanoic acid, O-deacylation and saponification of the methyl ester group, gave the title ganglioside. 相似文献