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71.
Fumihiko Kitagawa Kana Tanigawa‐Joh Satomi Terashita Ryohei Fujiki Isoshi Nukatsuka Kenji Sueyoshi Koji Otsuka 《Electrophoresis》2019,40(18-19):2478-2483
In this study, we found that the polarity switching was effective to enrich and separate fluorescent analytes which have weakly‐dissociated groups in a floating platinum electrode (width, 50 µm; thickness, 2.5 µm)‐integrated straight‐channel in microchip electrophoresis (MCE). In the straight channel filled with an Alexa Flour 488 (AF488) solution, a sharp peak was observed after the polarity inversion with a 530‐fold enhancement of the sensitivity relative to the conventional MCE analysis. By using a fluorescent pH indicator, we verified that a sharp high‐pH zone was generated nearby the floating electrode and moved toward the anode with maintaining the high pH, which induced the sample enrichment like a dynamic pH junction mechanism. In the floating electrode‐embedded channel, the mixture of AF488‐labeled proteins was also well concentrated and separated within 100 s. 相似文献
72.
In this paper, a coupled MPS-modal superposition method is developed for 2D nonlinear fluid-structure interaction problems. In this method, the rigid-body and relatively small elastic deformation are coupled together, which considers the mutual effect between them. The elastic deformation of the structure is represented by a mode superposition formulation, which is more efficient compared with FEM, regardless of the size of the structure. For 2D cases, if the first three modes are chosen to represent the flexible deformation of the structure, it only results in a 6×6 matrix equation to be solved. For the fluid motion, the modified Moving Particle Semi-implicit (MPS) method, which significantly reduces the fluctuation of pressure calculation of the original MPS method, is used.Two nonlinear problems, i.e. breaking-water-dam impacting a floating beam and flexible wedge slamming into the water are simulated to demonstrate the performance of the developed method. The numerical simulations show that this coupling model is capable of providing stable results that are generally in good agreement with the available experimental data. For the highly nonlinear case with very large rigid motions, the mutual effect between elastic deformation and rigid motions could accumulate to a relatively remarkable level shown by the curves of trajectories or acceleration history of the body mass centre. This also indicates the importance of mutual effect to analyse highly nonlinear FSI problems with large rigid-body motions and relatively small flexible deformation. 相似文献
73.
This paper presents results of numerical computations for floating off-shore wind turbines using, as an example, a machine of 10-MW rated power. The aerodynamic loads on the rotor are computed using the Helicopter Multi-Block flow solver developed at the University of Liverpool. The method solves the Navier–Stokes equations in integral form using the arbitrary Lagrangian–Eulerian formulation for time-dependent domains with moving boundaries. Hydrodynamic loads on the support platform are computed using the Smoothed Particle Hydrodynamics method, which is mesh-free and represents the water and floating structures by a set of discrete elements, referred to as particles. The motion of the floating offshore wind turbine is computed using a Multi-Body Dynamic Model of rigid bodies and frictionless joints. Mooring cables are modelled as a set of springs and dampers. All solvers were validated separately before coupling, and the results are presented in this paper. The importance of coupling is assessed and the loosely coupled algorithm used is described in detail alongside the obtained results. 相似文献
74.
We study the electrical characteristics of a MOS structure in which Pt nanoparticles are embedded. This structure has a tunneling oxide of 3.5 nm in thickness (a SiO2 thermal oxide layer) on top of a Si wafer, and a control oxide of 27 nm (HfO2 layer deposited by electron gun evaporation). The nanoparticles are deposited on the SiO2 layer with electron gun evaporation, at room temperature. The electrical study of the structures demonstrates that the “write” process is initiated at low electric fields. This indicates that this type of memory structure can be very promising for the fabrication of high speed MOSFET memory devices with low power consumption. Our charge retention measurements also show promising results. 相似文献
75.
Non-empirical band-structure calculations have been performed on polyethylene using two basis sets introduced by Christoffersen. Both basis sets had to be optimised with respect to the carbon-carbon framework bond in order to yield solutions within the nearest-neighbour approximations. The valence bands of polyethylene are well reproduced by both basis sets whilst the conduction bands are only in fair agreement with those produced by conventional gaussian calculations. The use of the unsplit basis set was considered unsatisfactory for the representation of the core bands. The effect of increasing the number of interacting unit cells on the energy terms is discussed. Some of the energy terms converge when five unit cells are used and almost all of the terms reach a constant value when nine unit cells are employed. 相似文献
76.
77.
A modified variational approach is presented to study the behavior of piled raft foundation under vertical loads. The free-body for analysis is a flexible raft isolated from piled raft foundation instead of pile group–soil system or whole pile raft system, which are usually used in other researches. The deflected shape of raft is represented by a function with a set of undetermined coefficients and the interactions between piles and/or the surface loads of soil are evaluated by a simplified approximate analytical solution. The response of the piled raft system is determined by the principle of minimum potential energy. Compared to other rigorous approaches, the present method is computationally efficient and inexpensive. The solutions obtained using the present method of analysis are shown to be in good agreement with other available published results. 相似文献
78.
浮筏隔振系统功率流特性分析 总被引:9,自引:0,他引:9
针对工程实际中浮筏隔振装置,建立了柔性基础上机组多支承弹性浮筏耦合隔振系统动力学普遍模型,提出了子系统动态特性综合分析法,给出了耦合系统动态传递方程及功率流表达式。根据工程中两机组浮筏隔振系统功率流理论计算结果,着重探讨安装频率与支承结构柔性耦合作用及其对隔振效果影响。研究结果表明:合理设计安装频率,可有效控制振动能量传输。 相似文献
79.
Alex P. Danielson Dylan Bailey‐ Van Kuren Melissa E. Lucius Katherine Makaroff Cameron Williams Richard C. Page Jason A. Berberich Dominik Konkolewicz 《Macromolecular rapid communications》2016,37(4):362-367
Enzymatic catalysis and control over macromolecular architectures from reversible addition‐fragmentation chain transfer polymerization (RAFT) are combined to give a new method of making polymers. Horseradish peroxidase (HRP) is used to catalytically generate radicals using hydrogen peroxide and acetylacetone as a mediator. RAFT is used to control the polymer structure. HRP catalyzed RAFT polymerization gives acrylate and acrylamide polymers with relatively narrow molecular weight distributions. The polymerization is rapid, typically exceeding 90% monomer conversion in 30 min. Complex macromolecular architectures including a block copolymer and a protein‐polymer conjugate are synthesized using HRP to catalytically initiate RAFT polymerization.
80.
Ole Caprani 《BIT Numerical Mathematics》1971,11(3):271-275
The method of Linz [1] for accurate floating-point summation has been programmed in Algol 60. The accuracy obtained confirms the analysis given by Linz. However, similar accuracy may be obtained with the use of quasi-double-precision [2]. 相似文献