The styrene-butadiene-styrene(SBS) modified bitumens with different contents of SBS modifiers are stored in different conditions to study the storage stability of SBS modified bitumen.Mixed-level orthogonal array de...The styrene-butadiene-styrene(SBS) modified bitumens with different contents of SBS modifiers are stored in different conditions to study the storage stability of SBS modified bitumen.Mixed-level orthogonal array design(OAD) is used and factors such as SBS modifier content,storage time,storage temperature and container size are chosen in a mixed-level OAD with an OA16(31×44) matrix.Parameters like the separation softening point difference(the separation difference of the ring and ball softening point of the top and bottom samples) and the average softening point(the arithmetic mean of the softening points of the top and bottom samples) are proposed to evaluate the separation and the ageing of modified bitumen during storage in this experiment,respectively.The results reveal that the separation and the ageing during storage exhibit a complicated variation for storage temperature and time.The separation softening point difference decreases with the storage temperature rising from 20 to 120 ℃ and increases with the temperature exceeding 120 ℃,and the average softening point drops with the storage time being prolonged.Different storage conditions have various effects on the storage stability of SBS modified bitumen.展开更多
The stability analysis is one of the chief problems at hydropower stations.The Jinjia Hydropower Station is a significant project in Southwest China.The paper adopts the rigidity limited equilibrium theory and evaluat...The stability analysis is one of the chief problems at hydropower stations.The Jinjia Hydropower Station is a significant project in Southwest China.The paper adopts the rigidity limited equilibrium theory and evaluated stability of the slope body,which will provide the evidences for further detail design.展开更多
Hydrogels are a class of special materials that contain a large amount of water and behave like rubber.These materials have found broad applications in tissue engineering,cell culturing,regenerative medicine etc.Recen...Hydrogels are a class of special materials that contain a large amount of water and behave like rubber.These materials have found broad applications in tissue engineering,cell culturing,regenerative medicine etc.Recently,the exploration of peptide-based supramolecular hydrogels has greatly expanded the repertoire of hydrogels suitable for biomedical applications.However,the mechanical properties of peptide-based hydrogels are intrinsically weak.Therefore,it is crucial to develop methods that can improve the mechanical stability of such peptide-based hydrogels.In this review,we explore the factors that determine or influence the mechanical stability of peptide-based hydrogels and summarize several key elements that may guide scientists to achieve mechanically improved hydrogels.In addition,we exemplified several methods that have been successfully developed to prepare hydrogels with enhanced mechanical stability.These mechanically strong peptide-based hydrogels may find broad applications as novel biomaterials.It is still challenging to engineer hydrogels in order to mimic the mechanical properties of biological tissues.More hydrogel materials with optimal mechanical properties suitable for various types of biological applications will be available in the near future.展开更多
基金The National Natural Science Foundation of China (No.51178348)
文摘The styrene-butadiene-styrene(SBS) modified bitumens with different contents of SBS modifiers are stored in different conditions to study the storage stability of SBS modified bitumen.Mixed-level orthogonal array design(OAD) is used and factors such as SBS modifier content,storage time,storage temperature and container size are chosen in a mixed-level OAD with an OA16(31×44) matrix.Parameters like the separation softening point difference(the separation difference of the ring and ball softening point of the top and bottom samples) and the average softening point(the arithmetic mean of the softening points of the top and bottom samples) are proposed to evaluate the separation and the ageing of modified bitumen during storage in this experiment,respectively.The results reveal that the separation and the ageing during storage exhibit a complicated variation for storage temperature and time.The separation softening point difference decreases with the storage temperature rising from 20 to 120 ℃ and increases with the temperature exceeding 120 ℃,and the average softening point drops with the storage time being prolonged.Different storage conditions have various effects on the storage stability of SBS modified bitumen.
文摘The stability analysis is one of the chief problems at hydropower stations.The Jinjia Hydropower Station is a significant project in Southwest China.The paper adopts the rigidity limited equilibrium theory and evaluated stability of the slope body,which will provide the evidences for further detail design.
基金supported by the National Natural Science Foundation of China(Grant Nos.11304156,11334004,91127026,31170813 and 11074115)China Postdoctoral Science Foundation(Grant No.2013M531312)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Program for New Century Excellent Talents in University
文摘Hydrogels are a class of special materials that contain a large amount of water and behave like rubber.These materials have found broad applications in tissue engineering,cell culturing,regenerative medicine etc.Recently,the exploration of peptide-based supramolecular hydrogels has greatly expanded the repertoire of hydrogels suitable for biomedical applications.However,the mechanical properties of peptide-based hydrogels are intrinsically weak.Therefore,it is crucial to develop methods that can improve the mechanical stability of such peptide-based hydrogels.In this review,we explore the factors that determine or influence the mechanical stability of peptide-based hydrogels and summarize several key elements that may guide scientists to achieve mechanically improved hydrogels.In addition,we exemplified several methods that have been successfully developed to prepare hydrogels with enhanced mechanical stability.These mechanically strong peptide-based hydrogels may find broad applications as novel biomaterials.It is still challenging to engineer hydrogels in order to mimic the mechanical properties of biological tissues.More hydrogel materials with optimal mechanical properties suitable for various types of biological applications will be available in the near future.