对实验室用 MOCVD方法生长的未掺杂 Ga N单晶膜的发光性能进行了研究。结果表明 :在室温时未掺杂 Ga N单晶出现的能量为 2 .9e V左右蓝带发光与补偿度有较强的依赖关系。高补偿 Ga N的蓝带发射强 ,低补偿 Ga N的蓝带发射弱。对蓝带发光...对实验室用 MOCVD方法生长的未掺杂 Ga N单晶膜的发光性能进行了研究。结果表明 :在室温时未掺杂 Ga N单晶出现的能量为 2 .9e V左右蓝带发光与补偿度有较强的依赖关系。高补偿 Ga N的蓝带发射强 ,低补偿 Ga N的蓝带发射弱。对蓝带发光机理进行了探讨 ,认为蓝带为导带电子跃迁至受主能级的发光 ( e A发光 )。观察到降低 Ga N补偿度能提高 Ga N带边发射强度。展开更多
湿地补偿率是湿地占用补偿制度实施的重要依据。回顾了国外湿地补偿率的确定依据和方法,为中国湿地补偿制度的建立和湿地补偿率的制定提供借鉴。湿地补偿率的确定,主要依据补偿措施、湿地类型、湿地功能和价值、地理位置、时间、湿地补...湿地补偿率是湿地占用补偿制度实施的重要依据。回顾了国外湿地补偿率的确定依据和方法,为中国湿地补偿制度的建立和湿地补偿率的制定提供借鉴。湿地补偿率的确定,主要依据补偿措施、湿地类型、湿地功能和价值、地理位置、时间、湿地补偿的成功率或失败率等因素。湿地补偿率的确定方法主要包括King D M和Bohlen C B提出的湿地补偿率模型及King D M和Price E W提出的改进的湿地补偿率模型、选择实验法和失败率法。在中国,目前湿地补偿率的确定需要制度保障、实践经验的积累和技术方法的支持。展开更多
根据冀北地区万顺500 k V特高压输电线路建立模型,分析串联补偿线路出现"电流反向"问题的根本原因和可能性。结合万顺具体算例,研究串补线路中差动比例系数K值在不同故障点、串补度、经高阻接地和MOV是否被击穿等情况下的变...根据冀北地区万顺500 k V特高压输电线路建立模型,分析串联补偿线路出现"电流反向"问题的根本原因和可能性。结合万顺具体算例,研究串补线路中差动比例系数K值在不同故障点、串补度、经高阻接地和MOV是否被击穿等情况下的变化趋势。代入现状运行方式下的具体参数,通过RTDS对模型进行数字模拟实验,深入探讨单双回串补线路运行状况下串联补偿对零序差动和分相差动保护动作特性的影响,得出过渡电阻、故障点、系统参数以及负荷变化等情况的差动保护动作结论,并给出万顺串联补偿线路保护装置的合理改进建议。展开更多
Rockburst disasters occur frequently during deep underground excavation,yet traditional concepts and methods can hardly meet the requirements for support under high geo-stress conditions.Consequently,rockburst control...Rockburst disasters occur frequently during deep underground excavation,yet traditional concepts and methods can hardly meet the requirements for support under high geo-stress conditions.Consequently,rockburst control remains challenging in the engineering field.In this study,the mechanism of excavation-induced rockburst was briefly described,and it was proposed to apply the excavation compensation method(ECM)to rockburst control.Moreover,a field test was carried out on the Qinling Water Conveyance Tunnel.The following beneficial findings were obtained:Excavation leads to changes in the engineering stress state of surrounding rock and results in the generation of excess energy DE,which is the fundamental cause of rockburst.The ECM,which aims to offset the deep excavation effect and lower the risk of rockburst,is an active support strategy based on high pre-stress compensation.The new negative Poisson’s ratio(NPR)bolt developed has the mechanical characteristics of high strength,high toughness,and impact resistance,serving as the material basis for the ECM.The field test results reveal that the ECM and the NPR bolt succeed in controlling rockburst disasters effectively.The research results are expected to provide guidance for rockburst support in deep underground projects such as Sichuan-Xizang Railway.展开更多
针对水光互补系统各电站补偿关系复杂且补偿效益分摊难以量化的问题,提出一种适用于量化水光互补系统效益补偿关系的求解方法,通过对梯级优化调度及水光互补优化调度后发电量的对比,得出水光互补动态过程指标和静态特性指标,建立水光互...针对水光互补系统各电站补偿关系复杂且补偿效益分摊难以量化的问题,提出一种适用于量化水光互补系统效益补偿关系的求解方法,通过对梯级优化调度及水光互补优化调度后发电量的对比,得出水光互补动态过程指标和静态特性指标,建立水光互补补偿效益分摊模型,并采用改进的客观权重赋权-优劣解距离法(criteria importance through intercriteria correlation-technique for order preference by similarity to an ideal solution,CRITIC-TOPSIS)求解补偿效益分摊比例,明晰各电站之间的损益关系。以澜沧江上游西藏段水光互补清洁能源基地为例进行求解,结果表明该方法考虑梯级水电站与光伏电站间的利益关系,同时兼顾梯级水电站内部的效益得失,分摊结果公平合理,可以平衡各主体之间的利害关系,有利于调动施益主体参与互补运行的积极性,实现清洁能源基地整体效益最大化。展开更多
文摘对实验室用 MOCVD方法生长的未掺杂 Ga N单晶膜的发光性能进行了研究。结果表明 :在室温时未掺杂 Ga N单晶出现的能量为 2 .9e V左右蓝带发光与补偿度有较强的依赖关系。高补偿 Ga N的蓝带发射强 ,低补偿 Ga N的蓝带发射弱。对蓝带发光机理进行了探讨 ,认为蓝带为导带电子跃迁至受主能级的发光 ( e A发光 )。观察到降低 Ga N补偿度能提高 Ga N带边发射强度。
文摘湿地补偿率是湿地占用补偿制度实施的重要依据。回顾了国外湿地补偿率的确定依据和方法,为中国湿地补偿制度的建立和湿地补偿率的制定提供借鉴。湿地补偿率的确定,主要依据补偿措施、湿地类型、湿地功能和价值、地理位置、时间、湿地补偿的成功率或失败率等因素。湿地补偿率的确定方法主要包括King D M和Bohlen C B提出的湿地补偿率模型及King D M和Price E W提出的改进的湿地补偿率模型、选择实验法和失败率法。在中国,目前湿地补偿率的确定需要制度保障、实践经验的积累和技术方法的支持。
文摘根据冀北地区万顺500 k V特高压输电线路建立模型,分析串联补偿线路出现"电流反向"问题的根本原因和可能性。结合万顺具体算例,研究串补线路中差动比例系数K值在不同故障点、串补度、经高阻接地和MOV是否被击穿等情况下的变化趋势。代入现状运行方式下的具体参数,通过RTDS对模型进行数字模拟实验,深入探讨单双回串补线路运行状况下串联补偿对零序差动和分相差动保护动作特性的影响,得出过渡电阻、故障点、系统参数以及负荷变化等情况的差动保护动作结论,并给出万顺串联补偿线路保护装置的合理改进建议。
基金supported by the National Natural Science Foundation of China (41941018)the Foundation of State Key Laboratory for Geomechanics and Deep Underground Engineering (SKLGDUEK 2217)the Foundation of Collaborative Innovation Center for Prevention and Control of Mountain Geological Hazards of Zhejiang Province (PCMGH-2022-03).
文摘Rockburst disasters occur frequently during deep underground excavation,yet traditional concepts and methods can hardly meet the requirements for support under high geo-stress conditions.Consequently,rockburst control remains challenging in the engineering field.In this study,the mechanism of excavation-induced rockburst was briefly described,and it was proposed to apply the excavation compensation method(ECM)to rockburst control.Moreover,a field test was carried out on the Qinling Water Conveyance Tunnel.The following beneficial findings were obtained:Excavation leads to changes in the engineering stress state of surrounding rock and results in the generation of excess energy DE,which is the fundamental cause of rockburst.The ECM,which aims to offset the deep excavation effect and lower the risk of rockburst,is an active support strategy based on high pre-stress compensation.The new negative Poisson’s ratio(NPR)bolt developed has the mechanical characteristics of high strength,high toughness,and impact resistance,serving as the material basis for the ECM.The field test results reveal that the ECM and the NPR bolt succeed in controlling rockburst disasters effectively.The research results are expected to provide guidance for rockburst support in deep underground projects such as Sichuan-Xizang Railway.
文摘针对水光互补系统各电站补偿关系复杂且补偿效益分摊难以量化的问题,提出一种适用于量化水光互补系统效益补偿关系的求解方法,通过对梯级优化调度及水光互补优化调度后发电量的对比,得出水光互补动态过程指标和静态特性指标,建立水光互补补偿效益分摊模型,并采用改进的客观权重赋权-优劣解距离法(criteria importance through intercriteria correlation-technique for order preference by similarity to an ideal solution,CRITIC-TOPSIS)求解补偿效益分摊比例,明晰各电站之间的损益关系。以澜沧江上游西藏段水光互补清洁能源基地为例进行求解,结果表明该方法考虑梯级水电站与光伏电站间的利益关系,同时兼顾梯级水电站内部的效益得失,分摊结果公平合理,可以平衡各主体之间的利害关系,有利于调动施益主体参与互补运行的积极性,实现清洁能源基地整体效益最大化。
