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91.
92.
A method for damage estimation of a bridge structure is presented using ambient vibration data caused by the traffic loadings. The procedure consists of identification of the operational modal properties and the assessment of damage locations and severities. An experimental study is carried out on a bridge model with a composite cross-section subjected to vehicle loadings. Vertical accelerations of the bridge deck are measured while vehicles are running. The modal parameters are identified from the free-decay signals extracted using the random decrement method. The damage assessment is carried out based on the estimated modal parameters using the neural networks technique. As input to the neural networks, the ratios of the resonant frequencies between before and after damages and the mode shapes after the damages are used to take into account the mass effect of the traffic on the bridge. The identified damage locations and severities agree reasonably well with the inflicted damages on the structure. 相似文献
93.
The substituted phenanthrene-9-carboxyaldehydes are very important intermediates for the syntheses of phenanthroindolizidine and phenanthroquinolizidine alkaloids. The novel title compound was prepared from the reaction of 5 steps starting from the condensation of 3-methoxyl-4-methyl-phenylacetic acid and 4-(benzyloxy)-2-iodobenzaldehyde, followed by esterification, cyclization, reduction, and oxidation. A new method for the preparation of phenanthrene ring via palladium-catalyzed intramolecular Heck reaction was described. The title compound was characterized by IR, ^1H NMR, ^13C NMR, elemental analysis, and MS. 相似文献
94.
柠檬酸盐法制备(Na0.5 Bi0.5)1-xBaxTiO3压电陶瓷的极化特性研究 总被引:2,自引:1,他引:1
采用柠檬酸盐法合成了具有单一钙钛矿结构的(Nao5Bio5)1-xBaxTiO3(x=0,x=0.04)超细粉料,并研究了陶瓷样品的极化特性、压电性能和铁电性能.研究结果表明,柠檬酸与金属离子的摩尔比(C/M)控制在1.2~1.6、前驱体液的pH值控制在7~9范围内可以得到均匀透明的溶胶和凝胶,凝胶在600℃下热处理1h后可形成单一钙钛矿结构的超细粉料.XRD研究结果表明,x=0和x=0.04时陶瓷样品均为三方钙钛矿结构.极化电压和极化温度对陶瓷样品的压电性能有很大影响,而极化时间对压电性能的影响则不显著.Ba2+的固溶改善了陶瓷样品的铁电性能,有利于材料极化性能和压电性能的提高.与常规固相法制备的同种组成样品相比,柠檬酸盐法制备的(Nao5Bi0.5)1-xBaxTiO3(x=0,x=0.04)陶瓷具有较好的压电性能. 相似文献
95.
In this paper, we develop the theory of demi-distributions which generalizes the usual distribution theory. In particular, we show that many results on differentiations, Fourier transforms, and convolutions can be generalized to demi-distributions theory. 相似文献
96.
Takuya FUKUSHIMA Takashi TANAKA Suguru FUKUSHIMA Mizuki WATANABE Jun AOKI Ayumu ITO Yoshihiro INAMOTO Sung-Won KIM Akira KAWAI Takahiro FUKUDA 《Physical Therapy Research》2022,25(3):162
Purpose: Physical activity (PA) interventions positively affect the physical function (PF) in patients with advanced cancer. However, patients must remain motivated during the intervention. We report a case wherein a smartphone application for PA intervention was useful in motivating the patient to improve adherence. Methods: A 40-year-old woman underwent an allogeneic hematopoietic cell transplantation (allo-HCT) for an advanced extranodal natural killer/T-cell lymphoma. On day 6, she developed the posterior reversible encephalopathy syndrome. She was managed in the intensive care unit for 3 days, and her PF declined markedly. We initiated a smartphone-based PA intervention from day 35. She was instructed to maintain a PA diary for self-monitoring of the daily steps and to set a new step-count goal every week. Results: The PA and PF improved within a short period thereafter. However, she developed severe acute graft-versus-host disease and was administered with high-dose systemic corticosteroids from day 49. The PA, PF, and quality of life (QOL) decreased again. The intervention was continued for 5 months with a high adherence. The PA, PF, and QOL improved gradually. She resumed independent activities of daily living and was discharged on day 202. Conclusion: Smartphone-based PA intervention may be effective against post-allo-HCT physical dysfunction. 相似文献
97.
98.
The authors mainly concern the set U f of c ?? ? such that the power deformation $ z(\frac{{f(z)}} {z})^c $ is univalent in the unit disk |z| < 1 for a given analytic univalent function f(z) = z + a 2 z 2 + ?? in the unit disk. It is shown that U f is a compact, polynomially convex subset of the complex plane ? unless f is the identity function. In particular, the interior of U f is simply connected. This fact enables us to apply various versions of the ??-lemma for the holomorphic family $ z(\frac{{f(z)}} {z})^c $ of injections parametrized over the interior of U f . The necessary or sufficient conditions for U f to contain 0 or 1 as an interior point are also given. 相似文献
99.
100.
Protein molecules are amphoteric and exist in aqueous solution as macromolecular ions that carry a charge which depends upon temperature and pH. Despite the repulsive Coulomb forces acting between them, protein macromolecular ions can form crystals in pH buffered solutions of strong electrolytes. It is proposed that the first step in the mechanism of crystallization is the formation of crystal nuclei made from partially discharged macromolecular ions that have exchanged H+ with the buffer. We suggest that the strength of the bare Coulomb repulsive force is weakened by the Debye-Hückel plasma screening provided by the inert electrolyte. This screening causes the rate of nucleus formation to increase with increasing ionic strength. Extending classic nucleation theory to account for these various charge effects, the results are applied to the case of lysozyme and a calculation is made of the dependence of the steady state nucleation rate upon temperature, pH, ionic strength, and protein supersaturation. It is found that the nucleation rate increases with increasing temperature and increasing ionic strength. Under condition of fixed temperature, supersaturation, and inionic strength, the nucleation rate has local maxima at low pH, where individual lysozyme macro ions are highly charged, and at pH ? 11, where they have zero average net charge. At both pH values, the nucleus that determines the rate has minimum size. In contrast to standard nucleation theory, which ignores charge, it is found that the size of the nucleus that controls the rate is different from the size of the nucleus that has the lowest concentration. All other conditions being the same, it is predicted that lysozyme crystals should nucleate most rapidly near pH = 2 and near pH = 11. 相似文献