A new method for three-dimensional simulation of the interaction between the gas and the solid around is developed.The effects of the gas on the thermal-mechanical behaviors within the surrounded solid are performed b...A new method for three-dimensional simulation of the interaction between the gas and the solid around is developed.The effects of the gas on the thermal-mechanical behaviors within the surrounded solid are performed by replacing the internal gas with an equivalent solid in the modeling,which can make it convenient to simulate the thermal-mechanical coupling effects in the solid research objects with gases in them.The applied thermal expansion coefficient,Young's modulus and Poisson's ratio of the equivalent solid material are derived.A series of tests have been conducted;and the proposed equivalent solid method to simulate the gas effects is validated.展开更多
The record of dinosaur eggs from the Upper Cretaceous Wangshi Group in eastern Shandong Province,China shows that the dinosaur species represented by elongatoolithids were present from the middle to the late Late Cret...The record of dinosaur eggs from the Upper Cretaceous Wangshi Group in eastern Shandong Province,China shows that the dinosaur species represented by elongatoolithids were present from the middle to the late Late Cretaceous,whereas those represented by the dictyoolithids and spheroolithids became extinct in the middle Late Cretaceous and the new species represented by ovaloolithids appeared in the late Late Cretaceous.Estimated eggshell conductance of water vapor is over 4 to over 115 times higher in spheroolithids and the dictyoolithids than in elongatoolithids and ovaloolithids,indicating that eggs of the first two oofamilies required higher humidity during incubation.Based on the18O record as preserved in eggshell,a change from relatively humid to relatively dry climatic conditions can be assumed to have taken place during the transition between the middle and late parts of the Late Cretaceous.It is reasonable to suggest that the change in climate was the cause of the dinosaur diversity.展开更多
基金Supported by Natural Science Foundation of China(Nos.10772049 and 11072062)Research and Development Program of China(863 Program, No.2009AA04Z408)+1 种基金Natural Science Foundation of Shanghai(No.06ZR14009)Pujiang Scholar Program and the Wangdao Scholar Program(No.08076) of Fudan University
文摘A new method for three-dimensional simulation of the interaction between the gas and the solid around is developed.The effects of the gas on the thermal-mechanical behaviors within the surrounded solid are performed by replacing the internal gas with an equivalent solid in the modeling,which can make it convenient to simulate the thermal-mechanical coupling effects in the solid research objects with gases in them.The applied thermal expansion coefficient,Young's modulus and Poisson's ratio of the equivalent solid material are derived.A series of tests have been conducted;and the proposed equivalent solid method to simulate the gas effects is validated.
基金supported by the National Natural Science Foundation of China(41172018 and 41202003)the National Key Basic Research Program of China(2012CB821900)the Special Founds for the Paleontology and Paleoanthropology,Academia Sinica(9118)
文摘The record of dinosaur eggs from the Upper Cretaceous Wangshi Group in eastern Shandong Province,China shows that the dinosaur species represented by elongatoolithids were present from the middle to the late Late Cretaceous,whereas those represented by the dictyoolithids and spheroolithids became extinct in the middle Late Cretaceous and the new species represented by ovaloolithids appeared in the late Late Cretaceous.Estimated eggshell conductance of water vapor is over 4 to over 115 times higher in spheroolithids and the dictyoolithids than in elongatoolithids and ovaloolithids,indicating that eggs of the first two oofamilies required higher humidity during incubation.Based on the18O record as preserved in eggshell,a change from relatively humid to relatively dry climatic conditions can be assumed to have taken place during the transition between the middle and late parts of the Late Cretaceous.It is reasonable to suggest that the change in climate was the cause of the dinosaur diversity.