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71.
Journal of Mechanical Science and Technology - This work reports on the position, velocity and acceleration analyses of a four-degrees-of-freedom parallel manipulator, 4-DoF-PM for brevity, which...  相似文献   
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Wireless Networks - Communication systems play an important role in smart grid (SG). Advanced Metering Infrastructure (AMI) is hybrid architecture in smart grid comprising of smart meters and...  相似文献   
75.
Journal of Superconductivity and Novel Magnetism - This study focuses on the temperature and hole content dependent fluctuation diamagnetism of hole-doped YBa2Cu3O7?δ (Y123) high-Tc...  相似文献   
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The results of research and development in the field of monitoring and control of oxygen content (thermodynamic activity) in heavy liquid metal coolants (Pb, Pb–Bi) are presented. The properties of lead and eutectics 44.5% Pb–55.5% Bi defining the specific features of their application as coolants in nuclear power plants are considered. Data on oxygen solubility in lead and lead–bismuth melts and the empirical dependences for calculation of the kinetic characteristics of lead oxide dissolution are given. Methods and devices for monitoring and control of the oxygen content (thermodynamic activity) in heavy coolants are considered.  相似文献   
78.
The potential of activated carbon prepared from kenaf fiber (KF) to remove copper (II) from aqueous effluents was investigated. The fibers were first semi-carbonized, then impregnated with potassium hydroxide (KOH) and finally activated by using carbon dioxide (CO2) gas to produce activated carbon. Pore structure and physical characteristics of the prepared kenaf fiber activated carbon (KFAC) were determined. Adsorption studies for divalent copper (Cu) ions were carried out to delineate the effect of contact time, temperature, pH and initial metal ion concentration on equilibrium adsorption capacity. The experimental data followed pseudo-second-order kinetics and Elovich Model than pseudo-first-order. Langmuir, Freundlich and Temkin models were implemented to analyze the parameters for adsorption at 30 °C, 50 °C and 70 °C. Thermodynamic parameters such as ??G o , ??H o and ??S o which represent Gibbs free energy, enthalpy and entropy, respectively, were evaluated. It was concluded that activated carbon from kenaf fiber (KFAC) can be used as an efficient adsorbent for removal of Cu (II) from synthetic wastewater.  相似文献   
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Vertically aligned ZnO nanorods (NRs) on aluminum-doped zinc oxide (AZO) substrates were fabricated by a single-step aqueous solution method at low temperature. In order to optimize optical quality, the effects of annealing on optical and structural properties were investigated by scanning electron microscopy, X-ray diffraction, photoluminescence (PL), and Raman spectroscopy. We found that the annealing temperature strongly affects both the near-band-edge (NBE) and visible (defect-related) emissions. The best characteristics have been obtained by employing annealing at 400°C in air for 2 h, bringing about a sharp and intense NBE emission. The defect-related recombinations were also suppressed effectively. However, the enhancement decreases with higher annealing temperature and prolonged annealing. PL study indicates that the NBE emission is dominated by radiative recombination associated with hydrogen donors. Thus, the enhancement of NBE is due to the activation of radiative recombinations associated with hydrogen donors. On the other hand, the reduction of visible emission is mainly attributed to the annihilation of OH groups. Our results provide insight to comprehend annealing effects and an effective way to improve optical properties of low-temperature-grown ZnO NRs for future facile device applications.  相似文献   
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