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61.
Positivity - We investigate some properties of strongly order bounded operators. For example, we prove that if a Riesz space E is an ideal in $$E^{sim sim }$$ and F is a Dedekind complete Riesz...  相似文献   
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There are ongoing studies on the potential use of chromene derivatives in liver cancer therapy. They have shown promising results in preclinical studies for liver cancer, including inhibiting tumor growth and inducing apoptosis. Herein, the nanosized hybrid material zinc oxide (ZnO)–cadmium sulfide (CdS) is prepared using a green and ecofriendly procedure. The nanomaterial was characterized by FE-SEM, transmission electron microscopy, energy dispersive X-ray, DRS, X-ray diffraction, and Fourier transform infrared spectroscopy. The photocatalytic proficiency of ZnO–CdS was then scrutinized in the fabrication of some 4H-chromenes in a mild condition. The outcomes of this study revealed that the nanophotocatalyst has high photocatalytic reactivity and acceptable reusability in the desired condensation reaction. Furthermore, a preliminary in vitro cellular toxicity assay was performed on ZnO–CdS nanoparticles using HepG2 cancer cell line through MTT assay.  相似文献   
63.
The solubility of carbon dioxide in a series of 1-(2-hydroxyethyl)-3-methylimidazolium ([hemim]+) based ionic liquids (ILs) with different anions, viz. hexafluorophosphate ([PF6]?), trifluoromethanesulfonate ([OTf]?), and bis-(trifluoromethyl)sulfonylimide ([Tf2N]?) at temperatures ranging from 303.15 K to 353.15 K and pressures up to 1.3 MPa were determined. The solubility data were correlated using the Krichevsky–Kasarnovsky equation and Henry’s law constants were obtained at different temperatures. Using the solubility data, the partial molar thermodynamic functions of solution such as Gibbs free energy, enthalpy, and entropy were calculated. Comparison showed that the solubility of CO2 in the ILs studied follows the same behaviour as the corresponding conventional 1-ethyl-3-methylimidazolium ([emim]+) based ILs with the same anions, i.e. [hemim][NTf2] > [hemim][OTf] > [hemim][PF6] > [hemim][BF4].  相似文献   
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Molecular dynamics simulations were conducted for a cubic Cu cluster supported on a graphite bilayer. The Sutten–Chen and Lennard–Jones potentials were used for metal–metal and metal–graphite interactions, respectively. Heating and cooling processes were performed by NVT simulations at different temperatures in the range 200 to 1800?K. The melting point was identified on the basis of caloric and heat capacity curves. The calculated melting point was 770?K, far below the bulk melting point of crystalline copper. Several phenomena such as the appearance of a hysteresis (irreversibility) in caloric curves, surface melting, and cluster-induced surface wetting were justified from the results. The simulation of cluster in the presence of gas atmosphere showed that the CO gas is adsorbed more than H2 and it has a greater impact on the cluster's structure.  相似文献   
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Density functional theory calculations have been used to investigate the rolling process of armchair boron nitride nanoribbons (n-ABNNRs, n?=?6,?8,?10,?12,?14,?16) to form (n,?0) zigzag boron nitrogen nanotubes (ZBNNTs, n?=?3–8). Results showed that by rolling (increasing the curvature) energy gap decreases and the difference between the initial and final states increases dramatically with decreasing the ribbon width. It was found that ZBNNTs have direct band gaps and the gap increases by diameter, while ABNNRs have direct band gaps which oscillate with the ribbon width.  相似文献   
67.
Nonlinear Dynamics - In this paper, the stick-slip motion of a new type of micro-robot with two perpendicular vibratory actuators is studied which is based on the friction drive principle. The...  相似文献   
68.
本工作将相互作用玻色子模型推广为包含f-和p-玻色子的情形。利用仿射型代数方法,通过对偶代数结构数值计算了多分量玻色型对力问题。利用对偶关系解析构建了与哈密顿量及其基底相联系的,由幺正的粒子数守恒和非粒子数守恒算符构成的准旋代数。在经该模型对106-116Cd偶偶核素实验能谱拟合的基础上,计算了基态和低激发态中各种玻色子占有率,准γ带中相邻能级摇摆等几个能特征该区域核素形状相变的序参量。从而展示了这些中重质量核从振动到γ-不稳定运动的形状相变行为。An extension of the original interacting boson model to the multi-level case including negative parity f-and p-bosons is made. An affinealgebraic approach is applied to solve the multi-level pairing problem numerically via the dual algebraic structure. The duality relation is explicitly used to construct the number-conserving unitary and number-nonconserving quasi-spin algebra, related with the Hamiltonian and the corresponding bases. After fitting to the experimental level energies of even-even 106-116Cd, several order parameters to signify the shape (phase) transition, such as occupation numbers of the bosons in the ground and a few lowest excited states, the level energy staggering in the (quasi)-γ band, are calculated to demonstrate the shape (phase) transitional behavior of these medium mass transitional nuclei.  相似文献   
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Extensive improvements in small-scale thermal systems in electronic circuits, automotive industries, and microcomputers conduct the study of microsystems as essential. Flow and thermic field characteristics of the coherent nanofluid-guided microchannel heat sink are described in this perusal. The porous media approximate was used to search the heat distribution in the expanded sheet and Cu: γ - ALOOH/Water. A hybrid blend of Boehme copper and aluminum nanoparticles is evaluated to have a cooling effect on the microchannel heat sink. By using Akbari Ganji and finite element methods, linear and non-linear differential equations as well as simple dimensionless equations have been analyzed. The purpose of this study is to investigate the fluid and thermal parameters of copper hybrid solution added to water, such as Nusselt number and Darcy number so that we can reach the best cooling of the fluid. Also, by installing a piece of fin on the wall of the heat sink, the coefficient of conductive heat transfer and displacement heat transfer with the surrounding air fluid increases, and the efficiency of the system increases. The overall results show that expanding values on the NP (Series heat transfer fluid system maximizes performance with temperatures) volume division of copper, as well as boehmite alumina particles, lead to a decrease within the stream velocity of the Cu: ALOOH/Water. Increasing the volume fraction of nanoparticles in the hybrid mixture decreases the temperature of the solid surface and the hybrid nanofluid. The Brownian movement improves as the volume percentage of nanoparticles in the hybrid mixture grows, spreading heat across the environment. As a result, heat transmission rates rise. As the Darcy number increases, the thermal field for solid sections and Cu: ALOOH/Water improves.  相似文献   
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