The made tea quality and chemical characteristics of 4 albinos cultivars were investigated. It shows that constitutes of micro-elements, contents of polyphenols and total amino acids in 4 samples are much different du...The made tea quality and chemical characteristics of 4 albinos cultivars were investigated. It shows that constitutes of micro-elements, contents of polyphenols and total amino acids in 4 samples are much different due to the biological diversity. The DPPH free radicals scavenging ability of the 4 albinos tea is also different. The free radicals scavenging rate has a significant positive correlation to the content of total polyphenols, total catechins, as well as C, CG, GCG, EGCG, but there is no positive relationship to the content of Zn, Se.展开更多
In this paper,a discrete tire model of comering properties for road vehicles relating to tire grip performance,which is important for driving stability and safety,is presented.The proposed tire model combines realisti...In this paper,a discrete tire model of comering properties for road vehicles relating to tire grip performance,which is important for driving stability and safety,is presented.The proposed tire model combines realistic rubber friction related to velocity and tire grip performance with deformation of the carcass.The model can describe the stress and strain of the carcass and tread,and the rubber friction coefficient at each point of the contact patch,which is affected by the di stribution of the slip velocity.Meanwhile,the model incorporates the effects of the viscoelastic rubber material and power spectrum of the road,which are explicitly reflected in the rubber friction model.First,an improved rubber friction model based on the Persson theory of rubber friction is introduced in this paper.A discrete analytical tire model,which considers carcass compliance and the discretization of the tread,is then proposed.In addition,important phenomena of tire properties arising from the carcass compl iance and rubber friction are analyzed and the effectiveness of the discrete analytical tire model is validated experimentally.The proposed model provides a new way to optimize the grip performance of a tire by adjusting the tire or rubber physical parameters even before the tire is made.展开更多
文摘The made tea quality and chemical characteristics of 4 albinos cultivars were investigated. It shows that constitutes of micro-elements, contents of polyphenols and total amino acids in 4 samples are much different due to the biological diversity. The DPPH free radicals scavenging ability of the 4 albinos tea is also different. The free radicals scavenging rate has a significant positive correlation to the content of total polyphenols, total catechins, as well as C, CG, GCG, EGCG, but there is no positive relationship to the content of Zn, Se.
基金supported by National Natural Science Foundation of China(Grant Nos.51875236 and 61790561)China Automobile Industry Innovation and Development Joint Fund(Grant Nos.U1664257 and U1864206).
文摘In this paper,a discrete tire model of comering properties for road vehicles relating to tire grip performance,which is important for driving stability and safety,is presented.The proposed tire model combines realistic rubber friction related to velocity and tire grip performance with deformation of the carcass.The model can describe the stress and strain of the carcass and tread,and the rubber friction coefficient at each point of the contact patch,which is affected by the di stribution of the slip velocity.Meanwhile,the model incorporates the effects of the viscoelastic rubber material and power spectrum of the road,which are explicitly reflected in the rubber friction model.First,an improved rubber friction model based on the Persson theory of rubber friction is introduced in this paper.A discrete analytical tire model,which considers carcass compliance and the discretization of the tread,is then proposed.In addition,important phenomena of tire properties arising from the carcass compl iance and rubber friction are analyzed and the effectiveness of the discrete analytical tire model is validated experimentally.The proposed model provides a new way to optimize the grip performance of a tire by adjusting the tire or rubber physical parameters even before the tire is made.
