Recently, the number of system interconnection of the renewable energy such as PV （photovoltaic） generation system and wind power generation system has been increasing drastically. A distribution system with the dis...Recently, the number of system interconnection of the renewable energy such as PV （photovoltaic） generation system and wind power generation system has been increasing drastically. A distribution system with the distributed generation must be operated keeping reliability of power supply and power quality. When high-capacity PV systems are interconnected to the distribution system, the system voltages may be deviated from the upper limit or lower limit of proper voltage in the distribution system. In this study, the authors propose a cooperative voltage control method of the distribution system by the power factor control of plural residential PV systems. In order to verify the validity of the proposal method, the numerical calculations are carried out by using an analytical model of distribution system which interconnected residential PV systems.展开更多
Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitati...Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitations, namely, low quantum yields(QYs), self-quenching,and excitation-dependent PL emission behaviors, severely impede the commercial applications of crystalline CNQDs.Here we address these three challenges by synthesizing borondoped amorphous CNQDs via a hydrothermal process followed by the top±down cutting approach. Structural disorder endows the amorphous boron-doped CNQDs(B-CNQDs)with superior elastic strain performance over a wide range of pH values, thus effectively promoting mass transport and reducing exciton quenching. Boron as a dopant could fine-tune the electronic structure and emission properties of the PL material to achieve excitation-independent emission via the formation of uniform boron states. As a result, the amorphous B-CNQDs show unprecedented fluorescent stability(i.e., no obvious fading after two years) and a high QY of 87.4%;these values indicate that the quantum dots obtained are very promising fluorescent materials. Moreover, the B-CNQDs show bright-blue fluorescence under ultraviolet excitation when applied as ink on commercially available paper and are capable of the selective and sensitive detection of Fe^(2+) and Cd^(2+) in the parts-per-billion range. This work presents a novel avenue and scientific insights on amorphous carbon-based fluorescent materials for photoelectrical devices and sensors.展开更多
文摘TN104.3 2000042279镝-镧-钛铁试剂荧光体系的协同发光效应及其分析应用=Columinescence effect of dysprosiumlanthanumtiron system and its application[刊,中]/王磊(山东医科大学药学系.山东(250012))
文摘Recently, the number of system interconnection of the renewable energy such as PV （photovoltaic） generation system and wind power generation system has been increasing drastically. A distribution system with the distributed generation must be operated keeping reliability of power supply and power quality. When high-capacity PV systems are interconnected to the distribution system, the system voltages may be deviated from the upper limit or lower limit of proper voltage in the distribution system. In this study, the authors propose a cooperative voltage control method of the distribution system by the power factor control of plural residential PV systems. In order to verify the validity of the proposal method, the numerical calculations are carried out by using an analytical model of distribution system which interconnected residential PV systems.
基金supported by the National Natural Science Foundation of China (51772085 and 12072110)the Natural Science Foundation of Hunan Province (2020JJ4190)。
文摘Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitations, namely, low quantum yields(QYs), self-quenching,and excitation-dependent PL emission behaviors, severely impede the commercial applications of crystalline CNQDs.Here we address these three challenges by synthesizing borondoped amorphous CNQDs via a hydrothermal process followed by the top±down cutting approach. Structural disorder endows the amorphous boron-doped CNQDs(B-CNQDs)with superior elastic strain performance over a wide range of pH values, thus effectively promoting mass transport and reducing exciton quenching. Boron as a dopant could fine-tune the electronic structure and emission properties of the PL material to achieve excitation-independent emission via the formation of uniform boron states. As a result, the amorphous B-CNQDs show unprecedented fluorescent stability(i.e., no obvious fading after two years) and a high QY of 87.4%;these values indicate that the quantum dots obtained are very promising fluorescent materials. Moreover, the B-CNQDs show bright-blue fluorescence under ultraviolet excitation when applied as ink on commercially available paper and are capable of the selective and sensitive detection of Fe^(2+) and Cd^(2+) in the parts-per-billion range. This work presents a novel avenue and scientific insights on amorphous carbon-based fluorescent materials for photoelectrical devices and sensors.
