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461.
462.
We introduce a web loop (P,
, +) which is precisely a loop (P,+) provided with the structure
of a web such that both structures are compatible in the sense that for eacha P the map a+PP;xa+x is an automorphism of (P,
). Exploiting the results of [6, 7, 9, Z] for the case of a web, we study web loops, webs with reflection structures and webs with point reflection structures.Dedicated to Professor Dr. Dr. h. c. Helmut Karzel on the occasion of his seventieth birthdayThis work was supported by CHONNAM NATIONNAL UNIVERSITY RESEARCH FUND, 1996 相似文献
463.
464.
Chae Young Kim Eun Sung Kang Seon Beom Kim Han Eol Kim Jae Hoon Choi Dong Sop Lee Se Jin Im Se Hwan Yang Young Chul Sung Byong Moon Kim Byung-Gee Kim 《Experimental & molecular medicine》2008,40(6):669-676
Pulse-induced permeabilization of cellular membranes, generally referred to as electroporation (EP), has been used for years as a tool to increase macromolecule uptake in tissues, including nucleic acids, for gene therapeutic applications, and this technique has been shown to result in improved immunogenicity. In this study, we assessed the utility of EP as a tool to improve the efficacy of HB-110, a novel therapeutic DNA vaccine against chronic hepatitis B, now in phase 1 of clinical study in South Korea. The potency of HB-110 in mice was shown to be improved by EP. The rapid onset of antigen expression and higher magnitude of humoral and cellular responses in electric pulse-treated mice revealed that EP may enable a substantial reduction in the dosage of DNA vaccine required to elicit a response similar in magnitude to that achievable via conventional administration. This study also showed that EP-based vaccination at 4-week-intervals elicited a cellular immune response which was about two-fold higher than the response elicited by conventional vaccination at 2-week intervals. These results may provide a rationale to reduce the clinical dose and increase the interval between the doses in the multidose vaccination schedule. Electric pulsing also elicited a more balanced immune response against four antigens expressed by HB-110: S, preS, Core, and Pol. 相似文献
465.
Dong-Kyun Im Jang Hyuck Kwon 《International Journal of Computational Fluid Dynamics》2015,29(1):82-99
The diagonally implicit harmonic balance method is developed in an overset mesh topology and applied to unsteady rotor flows analysis. Its efficiency is by reducing the complexity of a fully implicit harmonic balance method which becomes more flexible in handling the higher harmonics of the flow solutions. Applied to the overset mesh topology, the efficiency of the method becomes greater by reducing the number of solution interpolations required during the entire solution procedure as the method reduces the unsteady computation into periodic steady state. To verify the accuracy and efficiency of the method, both hovering and unsteady forward flight of Caradonna and Tung and AH-1G rotors are solved. Compared with wind-tunnel experiments, the numerical results demonstrate good agreements at computational cost an order of magnitude more efficient than the conventional time-accurate computation method. The proposed method has great potential in other engineering applications, including flapping wing vehicles, turbo-machinery, wind-turbines, etc. 相似文献
466.
467.
When S-termination on a Ge(1 0 0) surface was desorbed at an elevated temperature and an atomic layer deposition (ALD) HfO2 film was deposited, interfacial thickness was less than 1 nm. As a result, the equivalent oxide thickness (EOT) of the stack on the initially S-terminated surface was thinner than that deposited on the O3-oxidized surface, while HfO2 film thickness was almost identical on both surfaces. Nevertheless, the HfO2 stack on the initially S-terminated surface exhibited improved leakage current characteristics due to an increase in barrier height. Its thinner but robust interface will contribute to the scaling down of gate oxide integrity. 相似文献
468.
Lee J Chen J Brooks CL Im W 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,193(1):68-76
We have developed a set of orientational restraint potentials for solid-state NMR observables including (15)N chemical shift and (15)N-(1)H dipolar coupling. Torsion angle molecular dynamics simulations with available experimental (15)N chemical shift and (15)N-(1)H dipolar coupling as target values have been performed to determine orientational information of four membrane proteins and to model the structures of some of these systems in oligomer states. The results suggest that incorporation of the orientational restraint potentials into molecular dynamics provides an efficient means to the determination of structures that optimally satisfy the experimental observables without an extensive geometrical search. 相似文献
469.
In this study, the improvement of liftoff height of bluffbody-stabilized, partially premixed methane flames and the change
of flow field in the recirculation zone of bluffbodies, of variously modified base geometries, are investigated in a high
temperature (~1,315 K) vitiated flow. The basic geometry of the bluffbody consists of a two-dimensional rectangular body with
a rounded nose with fuel jets being discharged from the body at several locations upstream of the base. Flame liftoff height
measurements are characterized by CH chemiluminescence, while the three-dimensional flow field is determined using stereo
particle image velocimetry (PIV). The lowest liftoff height is observed when the geometric modifications from the original
rectangular bluffbody base are carried out such that the base has three-dimensional local cavities together with two-dimensionally
modified geometries. PIV measurements show that the improvement of liftoff height is primarily attributed to an intense recirculation
induced by multi-dimensional vortex structures in the presence of the two- and three-dimensionally modified base. 相似文献
470.
Direct numerical simulations were conducted to investigate the effect of two parameters, density ratio and laminar flame speed, on the conditions of the onset of local extinction and blow-off of lean premixed flames, stabilized on a meso-scale bluff-body in hydrogen-air and syngas–air mixtures. A total of six simulation cases were considered as isolated comparison of the two parametric effects of the fluid dynamic instability and flame time scale. For all cases under study, the general flame development towards the blow-off limit showed a sequence of five distinct modes, with possible cyclic patterns among the different modes for a range of velocity conditions. The onset of local extinction was observed during the asymmetric vortex shedding and vortex street mode. As the density ratio is decreased, the flow inunder reviewstability is promoted through the increased sinuous mode, and such behavior was properly scaled by the Strouhal number. Although the blow-off velocity is altered by the fluid dynamic effects, the condition for the onset of local extinction and blow-off was mainly dictated by the competition between flow residence time associated with the lateral flame motion and ignition delay of the local mixtures. Time scale analysis supported the validity of the findings across all the cases investigated. 相似文献