In this paper, analytical results from 3D temporal characteristics of the responses of an RC frame building subjected to both a large aflershock and the main shock of Wenchuan M8.0 earthquake are presented. The ground...In this paper, analytical results from 3D temporal characteristics of the responses of an RC frame building subjected to both a large aflershock and the main shock of Wenchuan M8.0 earthquake are presented. The ground motion records from the main shock were obtained from three nearby stations. The acceleration records were analyzed in terms of instantaneous tangential acceleration αv normal acceleration αN, Euclidean norm of acceleration vector lal, velocity vector ｜v｜, displacement vector ｜d｜, temporal curvature κ,κt, and temporal torsion γ and γt.Results of the kinematic relationship between the above factors and some additional in depth information obtained from extensive analyses are provided and discussed.展开更多
Eutrophication can shift lakes from a clear, macrophyte-dominated state state, and different habitat to a turbid, algae-dominated condition supports different fauna. Macrozoobenthos are good indicators of water enviro...Eutrophication can shift lakes from a clear, macrophyte-dominated state state, and different habitat to a turbid, algae-dominated condition supports different fauna. Macrozoobenthos are good indicators of water environment, and studies on macrozoobenthic assemblage characteristics can help us to know which state a lake is in, thus provide the basis for its eutrophication control. In this study, a systematic investigation on macrozoobenthos was conducted in 17 Yangtze-isolated lakes to explore the macroecological laws of macrozoobenthic assemblages. Detrended correspondence analysis （DCA） revealed that variance of benthic assemblage structure occurred in two types of lakes. In macrophytic lakes, altogether 51 taxa of macrozoobenthos were identified. The average density and biomass of total macrozoobenthos were 2231 individuals, m2 and 1.69 g dry weight.m-2, respec- tively. Macrozoobenthic assemblage was characterized by dominance of scrapers （i.e. gastropods）. In algal lakes, altogether 20 taxa of macrozoobenthos were identified. The average density and biomass of total macrozoobenthos were 2814 individuals.m^2 and 1.38g dry weight.m-2, respectively. Macrozoobenthic assemblage was character- ized by dominance of collector-gatherers （i.e. oligo- chaetes）. Wet biomass of submersed macrophytes （BMac） and phytoplankton chlorophyll a concentration （Chla） were demonstrated as the key factor structuring macro- zoobenthic assemblages in macrophytic and algal lakes, respectively.展开更多
基金NSFC program (No. 50678161)the National Major Basic Research 973 Program Under Grant No. 2007CB714205+1 种基金the Science and Technology Support Program Under Grant No. 2006BAC13B02-0301 of the Ministry of Science and Technology of Chinathe Basic Science Research Foundation Program through Institute of Engineering Mechanics, CEA
文摘In this paper, analytical results from 3D temporal characteristics of the responses of an RC frame building subjected to both a large aflershock and the main shock of Wenchuan M8.0 earthquake are presented. The ground motion records from the main shock were obtained from three nearby stations. The acceleration records were analyzed in terms of instantaneous tangential acceleration αv normal acceleration αN, Euclidean norm of acceleration vector lal, velocity vector ｜v｜, displacement vector ｜d｜, temporal curvature κ,κt, and temporal torsion γ and γt.Results of the kinematic relationship between the above factors and some additional in depth information obtained from extensive analyses are provided and discussed.
文摘Eutrophication can shift lakes from a clear, macrophyte-dominated state state, and different habitat to a turbid, algae-dominated condition supports different fauna. Macrozoobenthos are good indicators of water environment, and studies on macrozoobenthic assemblage characteristics can help us to know which state a lake is in, thus provide the basis for its eutrophication control. In this study, a systematic investigation on macrozoobenthos was conducted in 17 Yangtze-isolated lakes to explore the macroecological laws of macrozoobenthic assemblages. Detrended correspondence analysis （DCA） revealed that variance of benthic assemblage structure occurred in two types of lakes. In macrophytic lakes, altogether 51 taxa of macrozoobenthos were identified. The average density and biomass of total macrozoobenthos were 2231 individuals, m2 and 1.69 g dry weight.m-2, respec- tively. Macrozoobenthic assemblage was characterized by dominance of scrapers （i.e. gastropods）. In algal lakes, altogether 20 taxa of macrozoobenthos were identified. The average density and biomass of total macrozoobenthos were 2814 individuals.m^2 and 1.38g dry weight.m-2, respectively. Macrozoobenthic assemblage was character- ized by dominance of collector-gatherers （i.e. oligo- chaetes）. Wet biomass of submersed macrophytes （BMac） and phytoplankton chlorophyll a concentration （Chla） were demonstrated as the key factor structuring macro- zoobenthic assemblages in macrophytic and algal lakes, respectively.
