In this paper four families of orthogonal wavelets are applied to analyze the turbulent counter gradient transport phenomena in fully developed asymmetric channel flows. The results show that: (1) In the instance of c...In this paper four families of orthogonal wavelets are applied to analyze the turbulent counter gradient transport phenomena in fully developed asymmetric channel flows. The results show that: (1) In the instance of counter gradient transport, the principal scale of the coherent structure is responsible for the strong local counter gradient transport; (2) Counter gradient transport phenomena have a strong effect on the intermittency of turbulence; (3) Non-Gaussian part of the principal coherent structure is essential for counter gradient transport phenomena.展开更多
The counter gradient transport phenomena on momentum, energy and passive scalar in turbulent flows were studied by use of the single response friction for TSDIA. As a result, models that can describe qualitatively the...The counter gradient transport phenomena on momentum, energy and passive scalar in turbulent flows were studied by use of the single response friction for TSDIA. As a result, models that can describe qualitatively the phenomena are obtained. Then the results are simplified by use of the internal range theory, and the results for lower degrees agree with results of predecessor. Finally the counter gradient-transport phenomena in channel flow and circular wake flow are analyzed.展开更多
Thermal biology traits reflect thermal adaptations to an environment and can be used to infer responses to climate warming in animal species.Within a widespread genus or species,assessing the latitudinal or altitudina...Thermal biology traits reflect thermal adaptations to an environment and can be used to infer responses to climate warming in animal species.Within a widespread genus or species,assessing the latitudinal or altitudinal gradient of thermal physiological traits is essential to reveal thermal adaptations and determine future vulnerability to climate warming geographically.We determined the thermal biology traits of a cold-climate distributed lizard,Takydromus amurensis,and integrated published thermal biology traits within the genus Takydromus to reveal a preliminary geographical pattern in thermal adaptation.The mean selected body temperature(cloaca temperature;T_(sel)),critical thermal maximum(CT_(max)),critical thermal minimum(CT_(min)),and optimal temperature for locomotion(i.e.,sprint speed;T_(opt)) of T.amurensis were 32.6,45.1,3.1,and 33.4℃,respectively.The resting metabolic rates of T.amurensis were po sitively related to temperature from 18℃ to 38℃.We compared the traits of tropical T.sexlineatus,subtropical T.septentrionalis,and T.wolteri with T.amurensis and found that the CT_(max) and thermal tolerance range(the difference between CT_(max) and CT_(min);TTR) increased toward high latitudes,whereas CT_(min) increased toward low latitudes in these four Takydromus lizards.According to this preliminary pattern,we speculate the species at medium and low latitudes would be more vulnerable to extreme heat events caused by ongoing climate warming.We highlight the importance of integrating thermal biology traits along geographical clues,and its potential contribution to evaluate the vulnerabilities of species in the context of climate warming.展开更多
基金The project supported by the National Natural Science Foundation of China(10272071.10472063)
文摘In this paper four families of orthogonal wavelets are applied to analyze the turbulent counter gradient transport phenomena in fully developed asymmetric channel flows. The results show that: (1) In the instance of counter gradient transport, the principal scale of the coherent structure is responsible for the strong local counter gradient transport; (2) Counter gradient transport phenomena have a strong effect on the intermittency of turbulence; (3) Non-Gaussian part of the principal coherent structure is essential for counter gradient transport phenomena.
文摘The counter gradient transport phenomena on momentum, energy and passive scalar in turbulent flows were studied by use of the single response friction for TSDIA. As a result, models that can describe qualitatively the phenomena are obtained. Then the results are simplified by use of the internal range theory, and the results for lower degrees agree with results of predecessor. Finally the counter gradient-transport phenomena in channel flow and circular wake flow are analyzed.
基金supported by National Natural Science Foundation of China (31870391 and 31500324)supported by Youth Innovation Promotion Association CAS (No.2019085)。
文摘Thermal biology traits reflect thermal adaptations to an environment and can be used to infer responses to climate warming in animal species.Within a widespread genus or species,assessing the latitudinal or altitudinal gradient of thermal physiological traits is essential to reveal thermal adaptations and determine future vulnerability to climate warming geographically.We determined the thermal biology traits of a cold-climate distributed lizard,Takydromus amurensis,and integrated published thermal biology traits within the genus Takydromus to reveal a preliminary geographical pattern in thermal adaptation.The mean selected body temperature(cloaca temperature;T_(sel)),critical thermal maximum(CT_(max)),critical thermal minimum(CT_(min)),and optimal temperature for locomotion(i.e.,sprint speed;T_(opt)) of T.amurensis were 32.6,45.1,3.1,and 33.4℃,respectively.The resting metabolic rates of T.amurensis were po sitively related to temperature from 18℃ to 38℃.We compared the traits of tropical T.sexlineatus,subtropical T.septentrionalis,and T.wolteri with T.amurensis and found that the CT_(max) and thermal tolerance range(the difference between CT_(max) and CT_(min);TTR) increased toward high latitudes,whereas CT_(min) increased toward low latitudes in these four Takydromus lizards.According to this preliminary pattern,we speculate the species at medium and low latitudes would be more vulnerable to extreme heat events caused by ongoing climate warming.We highlight the importance of integrating thermal biology traits along geographical clues,and its potential contribution to evaluate the vulnerabilities of species in the context of climate warming.
