Break junctions are important in generating nanosensors and single molecular devices. The mechanically con- trollable break junction is the most widely used method for a break junction due to its simplicity and stabil...Break junctions are important in generating nanosensors and single molecular devices. The mechanically con- trollable break junction is the most widely used method for a break junction due to its simplicity and stability. However, the bandwidths of traditional devices are limited to about a few hertz. Moreover, when using traditional methods it is hard to allow independent control of more than one junction. Here we propose on-chip thermally controllable break junctions to overcome these challenges. This is verified by using finite element analysis. Adopting microelectromechanical systems produces features of high bandwidth and independent controllability to this new break junction system. The proposed method will have a wide range of applications on on-chip high speed independent controllable and highly integrated single molecule devices.展开更多
The characteristics of slope break during depression stage in the Songliao Basin of NE China are analyzed. It is indicated that double flexure slope breaks extend in a circle across the basin.One is nominated the inne...The characteristics of slope break during depression stage in the Songliao Basin of NE China are analyzed. It is indicated that double flexure slope breaks extend in a circle across the basin.One is nominated the inner slope break,and the other is the external slope break. Under different regional stress field,the control展开更多
The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be ...The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be used for general flatness control. However, it does not work for some special rolling processes, such as the elimination of ultra single side edge-waves and the prevention of strip break due to tilting roll control overshooting. For the purpose of solving these problems, the influences of non-symmetrical work roll bending and intermediate roll bending on flatness control were analyzed by studying efficiencies of them. Moreover, impacts of two kinds of non-symmetrical roll bending control on the pressure distribution between rolls were studied theoretically. A non-symmetrical work roll bending model was developed by theoretical analysis in accordance with practical conditions. The model was applied to the revamp of a 1250 6-H reversible universal crown mill (UCM) cold mill. Theoretical study and practical applications show that the coordination utilization of the non-symmetrical work roll bending control and tilting roll control was effective in flatness control when there appeared bad strip single side edge waves, especially when the incoming strip was with a wedge shape. In addition, the risk of strip break due to tilting control overshooting could be reduced. Furthermore, the non-symmetrical roll bending control can reduce the extent of uneven distribution of pressure between rolls caused by intermediate roll shifting in flatness control and slow down roll wear. The non-symmetrical roll bending control technology has important theoretical and practical significance to better flatness control.展开更多
集成超级电容串并联电源技术、IGBT精准控制技术、固态直流开关回路切换技术及虚拟仪器测控技术,构建了包含电源系统、回路切换系统、阻抗负载系统及测控系统的完整解决方案。系统可实现电压60~1500 V无级可调、电流4~30 k A精准输出,...集成超级电容串并联电源技术、IGBT精准控制技术、固态直流开关回路切换技术及虚拟仪器测控技术,构建了包含电源系统、回路切换系统、阻抗负载系统及测控系统的完整解决方案。系统可实现电压60~1500 V无级可调、电流4~30 k A精准输出,通电时间控制精度高,各项技术指标达到国际先进水平。成果已成功应用于新能源汽车核心零部件检测领域,为行业提供了可复制的智能化检测案例,推动了新能源汽车产业链的国产化进程与技术升级。展开更多
基金Supported by the National Key Basic Research Program of China under Grant No 2013CB921800the National Natural Science Foundation of China under Grant Nos 11227901,91021005,11274299,11104262 and 10834005the Strategic Priority Research Program(B)of the Chinese Academy of Sciences under Grant No XDB01030400
文摘Break junctions are important in generating nanosensors and single molecular devices. The mechanically con- trollable break junction is the most widely used method for a break junction due to its simplicity and stability. However, the bandwidths of traditional devices are limited to about a few hertz. Moreover, when using traditional methods it is hard to allow independent control of more than one junction. Here we propose on-chip thermally controllable break junctions to overcome these challenges. This is verified by using finite element analysis. Adopting microelectromechanical systems produces features of high bandwidth and independent controllability to this new break junction system. The proposed method will have a wide range of applications on on-chip high speed independent controllable and highly integrated single molecule devices.
文摘The characteristics of slope break during depression stage in the Songliao Basin of NE China are analyzed. It is indicated that double flexure slope breaks extend in a circle across the basin.One is nominated the inner slope break,and the other is the external slope break. Under different regional stress field,the control
基金supported by National Natural Science Foundation of China (Grant No. 50534020)
文摘The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be used for general flatness control. However, it does not work for some special rolling processes, such as the elimination of ultra single side edge-waves and the prevention of strip break due to tilting roll control overshooting. For the purpose of solving these problems, the influences of non-symmetrical work roll bending and intermediate roll bending on flatness control were analyzed by studying efficiencies of them. Moreover, impacts of two kinds of non-symmetrical roll bending control on the pressure distribution between rolls were studied theoretically. A non-symmetrical work roll bending model was developed by theoretical analysis in accordance with practical conditions. The model was applied to the revamp of a 1250 6-H reversible universal crown mill (UCM) cold mill. Theoretical study and practical applications show that the coordination utilization of the non-symmetrical work roll bending control and tilting roll control was effective in flatness control when there appeared bad strip single side edge waves, especially when the incoming strip was with a wedge shape. In addition, the risk of strip break due to tilting control overshooting could be reduced. Furthermore, the non-symmetrical roll bending control can reduce the extent of uneven distribution of pressure between rolls caused by intermediate roll shifting in flatness control and slow down roll wear. The non-symmetrical roll bending control technology has important theoretical and practical significance to better flatness control.
文摘集成超级电容串并联电源技术、IGBT精准控制技术、固态直流开关回路切换技术及虚拟仪器测控技术,构建了包含电源系统、回路切换系统、阻抗负载系统及测控系统的完整解决方案。系统可实现电压60~1500 V无级可调、电流4~30 k A精准输出,通电时间控制精度高,各项技术指标达到国际先进水平。成果已成功应用于新能源汽车核心零部件检测领域,为行业提供了可复制的智能化检测案例,推动了新能源汽车产业链的国产化进程与技术升级。
