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A current-source single-stage multi-input high-frequency-link grid-connected inverter and a three-mode one-cycle control strategy are proposed and deeply investigated in this paper. The inverter contains multiple current-source inverting units, a multi-input high-frequency transformer, and a cycloconverter. It achieves single-stage power conversion and high-frequency galvanic isolation with a simple circuit structure. The control strategy adds a by-pass switch to the energy storage inductor. It has energy-storing, energy-releasing, and three by-pass operation modes in a low frequency cycle. Through calculating the energy-releasing duty cycle in real time, the magnetic saturation problem of current-source inverters is solved and the output waveform quality is greatly improved. Soft-switching of the converter, a transfer function block diagram, and the design of the main circuit parameters are achieved. The simulation of a three-input inverter and experiment on a two-input inverter verify the feasibility and advancement of the proposed circuit topology and control strategy. [ABSTRACT FROM AUTHOR]

Due to the characteristics of bone metabolic microenvironment in the local area of osteoporotic bone defect, it is often difficult for ordinary bone repair materials to achieve satisfactory repair effect. In this study, a multifunctional Sr-substituted hydroxyapatite/reduced graphene oxide (Sr-HAp/RGO) 3D scaffold was fabricated by a one-step hydrothermal reduction method. Sr-HAp colloids with good dispersion stability were firstly prepared to prevent precipitation and aggregation during hydrothermal process. The Sr-HAp/RGO composite scaffold with porous structure has a high compressive strength due to the reinforcement of Sr-HAp nanoparticles. Alendronate sodium (ALN), a commonly used drug for the treatment of osteoporosis, can be effectively loaded on the Sr-HAp/RGO scaffold and released for a prolonged time. The as-prepared ALN-loaded Sr-HAp/RGO scaffold shows promising potential for osteoporotic bone defect repair. [ABSTRACT FROM AUTHOR]

Presents results of comprehensive full-dimensional (6D) quantum calculations of the rovibrational levels of hydrogen halide dimers for total angular momentum. Use of 6D potential energy surfaces in the calculations; Importance of including the intramolecular vibrations of two hydrochloric acid subunits in the comparison with four-dimensional bound state calculations.

Presents information on a study which examined the polarization effect in the measurement of thin wire diameter by laser diffraction. Methodology of the study; Results and discussion; Conclusion.

A nonlinear pulse width modulation-controlled single-phase boost mode photovoltaic grid-connected inverter with limited storage inductance current is proposed in this paper. The circuit topology, control strategy, steady-state principle characteristic, and design criterion for the key circuit parameters of this kind of inverter are investigated in depth, and important conclusions are obtained. The inverter's regenerating energy duty ratio 1–D which decreases with the decline of the grid-connected voltage is real time adapted by sampling and feeding back the inverting bridge modulation current, and the average value of the modulation current in each switching cycle tracks the reference sinusoidal signal to get high-quality grid-connected current. The active control of the energy storage inductance current and the balance of the voltage step-up ratio are realized by adding a bypass switch connected in parallel with the energy storage inductance and using two kinds of switching pattern namely boost pattern and freewheeling pattern. The theoretical analysis and experimental results of the 1 kVA 110 VDC/220 V50 Hz photovoltaic grid-connected inverter prototype show that it has the advantages such as single-stage boost conversion, high conversion efficiency, high quality of grid-connected current waveform, low value of energy storage inductance, simple control, etc. [ABSTRACT FROM AUTHOR]