A new fault isolation and restoration technique employing local Ethemet network for the looped MV circuit is presented. It can isolate all short circuit faults in the loop within 300 ms and restore the supply of healt...A new fault isolation and restoration technique employing local Ethemet network for the looped MV circuit is presented. It can isolate all short circuit faults in the loop within 300 ms and restore the supply of healthy sections in less than 1.2 s. A reliable fault location method of isolating the single phase-to-ground fault （SPGF） in the non-effectively earthed network, which makes use of the fault generated transient signals, is also proposed. And the method locates the SPGF by examining transient zero-mode current correlation, which is not influenced by the neutral grounding mode and need no additional device. Laboratory test and simulation results show the proposed techniques are feasible, and significantly improve the supply reliability.展开更多
Object： To observe the dynamic changes of dopamine （DA） in the striatum with the process of duplicating cerebral ischemia and reperfusion （CIR） model on rats. And observe the effect of electroacupuncture （EA） o...Object： To observe the dynamic changes of dopamine （DA） in the striatum with the process of duplicating cerebral ischemia and reperfusion （CIR） model on rats. And observe the effect of electroacupuncture （EA） on such changes. Methods： Using microdialysis sampling, high performance liquid chromatography （HPLC） detecting technology, dynamic sampling from experimental animals at multiple moments to observe the changes of dopamine in striatum with ischemia. And observe the effect of EA at Fengchi （GB 20） on such changes. Result： About the extracellular level of DA in normal group, sham-operation group and sham-operation ＋ EA group, no significant changes were observed during the measuring period. The extracellular level of DA peaked at 15-45 min after MCAO and 0-30 min （P〈0.05） after reperfusion. A rising trend was also observed following 120 min after reperfusion. After EA, the extracellular level of DA was significant lower than ischemia group following 90 min after reperfusion （P 〈0.05）. And there was no peak again. Conclusion： EA at Fenchi （GB 20） can regulate the disorder of DA. EA can improve the integrity neurological function. This may be one of the mechanisms of acupuncture treating the lesion of cerebral ischemia and reperfusion.展开更多
In this work, we have studied a new lead-free ceramic of（1-y）Bi1-xNdxFeO3-yBiScO3（0.05≤x≤0.15 and 0.05≤y≤0.15） prepared by a conventional solid-state method, and the influences of Nd and Sc content on their ph...In this work, we have studied a new lead-free ceramic of（1-y）Bi1-xNdxFeO3-yBiScO3（0.05≤x≤0.15 and 0.05≤y≤0.15） prepared by a conventional solid-state method, and the influences of Nd and Sc content on their phase structure and electrical properties were investigated in detail. The ceramics with 0.05≤x≤0.10 and 0.05≤y≤0.15 belong to an R3 c phase, and the rhombohedral-like and orthorhombic multiphase coexistence is established in the composition range of 0.125≤x≤0.15 and y=0. The electrical properties of the ceramics can be enhanced by modifying x and y values. The highest piezoelectric coefficient（d33～51 p C/N） is obtained in the ceramics with x=0.075 and y=0.125, which is superior to that of a pure BiFeO3 ceramic. In addition, a lowest dielectric loss（tan δ～0.095%, f=100 k Hz） is shown in the ceramics with x=0.15 and y=0 due to the involvement of low defect concentrations, and the improved thermal stability of piezoelectricity at 20–600℃ is possessed in the ceramics. We believe that the ceramics can play a meaningful role in the high-temperature lead-free piezoelectric applications.展开更多
文摘A new fault isolation and restoration technique employing local Ethemet network for the looped MV circuit is presented. It can isolate all short circuit faults in the loop within 300 ms and restore the supply of healthy sections in less than 1.2 s. A reliable fault location method of isolating the single phase-to-ground fault （SPGF） in the non-effectively earthed network, which makes use of the fault generated transient signals, is also proposed. And the method locates the SPGF by examining transient zero-mode current correlation, which is not influenced by the neutral grounding mode and need no additional device. Laboratory test and simulation results show the proposed techniques are feasible, and significantly improve the supply reliability.
基金the Science and Technology Commission of Shanghai Municipality(014319364)the Science Foundation of Shanghai Municipal Commission of Science and Technology(05DZ19745,06DZ19732,064319053,07DZ19722,07DZ19733)+1 种基金the National Basic Research Program of China(973 Program,2005CB523306)Shanghai Leading Academic Discipline Project(B112 and T0302)
文摘Object： To observe the dynamic changes of dopamine （DA） in the striatum with the process of duplicating cerebral ischemia and reperfusion （CIR） model on rats. And observe the effect of electroacupuncture （EA） on such changes. Methods： Using microdialysis sampling, high performance liquid chromatography （HPLC） detecting technology, dynamic sampling from experimental animals at multiple moments to observe the changes of dopamine in striatum with ischemia. And observe the effect of EA at Fengchi （GB 20） on such changes. Result： About the extracellular level of DA in normal group, sham-operation group and sham-operation ＋ EA group, no significant changes were observed during the measuring period. The extracellular level of DA peaked at 15-45 min after MCAO and 0-30 min （P〈0.05） after reperfusion. A rising trend was also observed following 120 min after reperfusion. After EA, the extracellular level of DA was significant lower than ischemia group following 90 min after reperfusion （P 〈0.05）. And there was no peak again. Conclusion： EA at Fenchi （GB 20） can regulate the disorder of DA. EA can improve the integrity neurological function. This may be one of the mechanisms of acupuncture treating the lesion of cerebral ischemia and reperfusion.
基金supported by the National Natural Science Foundation of China(Grant Nos.51102173&51472169)the College of Materials Science and Engineering of Sichuan University
文摘In this work, we have studied a new lead-free ceramic of（1-y）Bi1-xNdxFeO3-yBiScO3（0.05≤x≤0.15 and 0.05≤y≤0.15） prepared by a conventional solid-state method, and the influences of Nd and Sc content on their phase structure and electrical properties were investigated in detail. The ceramics with 0.05≤x≤0.10 and 0.05≤y≤0.15 belong to an R3 c phase, and the rhombohedral-like and orthorhombic multiphase coexistence is established in the composition range of 0.125≤x≤0.15 and y=0. The electrical properties of the ceramics can be enhanced by modifying x and y values. The highest piezoelectric coefficient（d33～51 p C/N） is obtained in the ceramics with x=0.075 and y=0.125, which is superior to that of a pure BiFeO3 ceramic. In addition, a lowest dielectric loss（tan δ～0.095%, f=100 k Hz） is shown in the ceramics with x=0.15 and y=0 due to the involvement of low defect concentrations, and the improved thermal stability of piezoelectricity at 20–600℃ is possessed in the ceramics. We believe that the ceramics can play a meaningful role in the high-temperature lead-free piezoelectric applications.
