Firstly,the common design principles for diversion tunnel plug are generalized,and two kinds of numerical analysis methods are discussed.Then the strength reduction FEM is introduced in numerical model analysis and th...Firstly,the common design principles for diversion tunnel plug are generalized,and two kinds of numerical analysis methods are discussed.Then the strength reduction FEM is introduced in numerical model analysis and the design steps of the plug's length are illustrated.During the progress to determine the plug's length,the equivalent plastic strain on the potential slip surface is assumed as the flag to tell the failure against sliding,and the plug stability is overall estimated from the plastic zone range and connectivity.展开更多
Echinops latifolius Tausch(ELT)is the traditional Mongolian medicine for the treatment of osteoporosis,and the ambiguous composition of active ingredients is an important factor in restricting the modernization and gl...Echinops latifolius Tausch(ELT)is the traditional Mongolian medicine for the treatment of osteoporosis,and the ambiguous composition of active ingredients is an important factor in restricting the modernization and globalization of this herb.Considering the traditional activity screening strategy is time-consuming and labor intensive,online HPLC active ingredient detection coupled with ESI-IT-TOF-MS^(n) strategy was employed in this study to isolate,identify and screen active compounds from the herbal medicines at the same time.The structure-activity relationship of these compounds was elucidated as well.Owing to the association of osteoporosis progression and oxidative stress,the antioxidants screening from ELT could be a good interpretive of the active substance in this herb.Meanwhile,DPPH equivalent method was an indicative of the most powerful antioxidant in ELT.Consequently,the screening and identification of the antioxidants in ELT was performed by using on-line HPLC-radical scavenging detection coupled with ESI-IT-TOF-MS^(n) strategy,and the structure-activity relationship was investigated based on DPPH equivalent method.Finally,20 constituents(including apigenin glucosides,caffeic acid,biscaffeoylquinic acids,biscaffeoylquinic acid methyl esters,ect.)were characterized in ELT extracts,and 18 components showed appreciable radical scavenging capacity.In addition,the structure-activity relationship study was carried out based on 14 compounds isolated from our laboratory,and the structural requirements of the compounds on antioxidant activity were obtained:(1)compounds with phenolic hydroxyl groups could have antioxidant activity;(2)the antioxidant activity could not be facilitated by the number of hydroxyl groups,but affected by the number of caffeoyl groups;(3)the substitution position of caffeoyl on quinic acid had a greater influence on DPPH activity;(4)methoxy groups could reduce the antioxidant activity.Collectively,this work provided the biochemical perspective to link active compounds and anti-osteoporosis action of ELT,and further explained how ELT worked in osteoporosis patients with bone loss.展开更多
In view of the high voltage, the strong magnetic field environment of the high-voltage switchgear, the system based on the optical wireless sensing technology, realizes the isolated contact temperature monitoring of t...In view of the high voltage, the strong magnetic field environment of the high-voltage switchgear, the system based on the optical wireless sensing technology, realizes the isolated contact temperature monitoring of the high-voltage switchgear. In this scheme, the good thermal conductivity and insulation ceramic materials were selected as the outer jacket material sensing probe, and the program had a good solution to the problem of high and low voltage isolation; The combination of the optical fiber composite insulators for wireless sensing, not only solves the problem of high voltage insulation, but also avoids the "creeping" phenomenon due to dust. The package of the structure and reasonable installation solves the cross sensitivity of strain. The application showed that the precision of temperature measurement of the system could reach ± 0.5 ℃ and could work in a variety of harsh environments. It could improve the reliability of the operation of the electrical equipment significantly and has considerable practical value for the whole power system.展开更多
基金National Natural Science Foundation of China(No.50809051)
文摘Firstly,the common design principles for diversion tunnel plug are generalized,and two kinds of numerical analysis methods are discussed.Then the strength reduction FEM is introduced in numerical model analysis and the design steps of the plug's length are illustrated.During the progress to determine the plug's length,the equivalent plastic strain on the potential slip surface is assumed as the flag to tell the failure against sliding,and the plug stability is overall estimated from the plastic zone range and connectivity.
基金National Natural Science Foundation of China(Grant No.81860756,81960758)Natural Science Foundation of Inner Mongolia Autonomous Region(Grant No.2017MS08122,2019MS08111 and 2019MS08119)+2 种基金Inner Mongolia Science and Technology Innovation Guide Project(Grant No.02039001)Rolling Support Plan for Grassland Talents Project in Inner Mongolia Autonomous RegionInner Mongolia Autonomous Region Higher Education Science Research Project(Grant No.NJZY19099)。
文摘Echinops latifolius Tausch(ELT)is the traditional Mongolian medicine for the treatment of osteoporosis,and the ambiguous composition of active ingredients is an important factor in restricting the modernization and globalization of this herb.Considering the traditional activity screening strategy is time-consuming and labor intensive,online HPLC active ingredient detection coupled with ESI-IT-TOF-MS^(n) strategy was employed in this study to isolate,identify and screen active compounds from the herbal medicines at the same time.The structure-activity relationship of these compounds was elucidated as well.Owing to the association of osteoporosis progression and oxidative stress,the antioxidants screening from ELT could be a good interpretive of the active substance in this herb.Meanwhile,DPPH equivalent method was an indicative of the most powerful antioxidant in ELT.Consequently,the screening and identification of the antioxidants in ELT was performed by using on-line HPLC-radical scavenging detection coupled with ESI-IT-TOF-MS^(n) strategy,and the structure-activity relationship was investigated based on DPPH equivalent method.Finally,20 constituents(including apigenin glucosides,caffeic acid,biscaffeoylquinic acids,biscaffeoylquinic acid methyl esters,ect.)were characterized in ELT extracts,and 18 components showed appreciable radical scavenging capacity.In addition,the structure-activity relationship study was carried out based on 14 compounds isolated from our laboratory,and the structural requirements of the compounds on antioxidant activity were obtained:(1)compounds with phenolic hydroxyl groups could have antioxidant activity;(2)the antioxidant activity could not be facilitated by the number of hydroxyl groups,but affected by the number of caffeoyl groups;(3)the substitution position of caffeoyl on quinic acid had a greater influence on DPPH activity;(4)methoxy groups could reduce the antioxidant activity.Collectively,this work provided the biochemical perspective to link active compounds and anti-osteoporosis action of ELT,and further explained how ELT worked in osteoporosis patients with bone loss.
文摘In view of the high voltage, the strong magnetic field environment of the high-voltage switchgear, the system based on the optical wireless sensing technology, realizes the isolated contact temperature monitoring of the high-voltage switchgear. In this scheme, the good thermal conductivity and insulation ceramic materials were selected as the outer jacket material sensing probe, and the program had a good solution to the problem of high and low voltage isolation; The combination of the optical fiber composite insulators for wireless sensing, not only solves the problem of high voltage insulation, but also avoids the "creeping" phenomenon due to dust. The package of the structure and reasonable installation solves the cross sensitivity of strain. The application showed that the precision of temperature measurement of the system could reach ± 0.5 ℃ and could work in a variety of harsh environments. It could improve the reliability of the operation of the electrical equipment significantly and has considerable practical value for the whole power system.