Plastic deformation of TiAI and TiAI-V intermetallic compounds has been studied by com- pression experiment at various temperatures and strain rates.Results show that the plastic deformation in distinct temperature ra...Plastic deformation of TiAI and TiAI-V intermetallic compounds has been studied by com- pression experiment at various temperatures and strain rates.Results show that the plastic deformation in distinct temperature range is principally controlled by the mechanisms of Peierls-Nabarro,cross slip and creep of dislocations.For TiAI-V alloy deformed at a range of 600—700 K,the negative strain rate dependence of flow stress was observed,i.e.,the more the plastic strain is.the more the negative dependence will be.A possible mechanism of the anomaly could be interpreted by thermal activation of dislocation cross slipping.The effects of temperature and strain rate on work-hardening exponent were also studied and discussed.展开更多
Objective: Prepare cross-linked HA gels with higher mechanical stability, lower degradation velocity and desirable biocompatibility,so as to extend the usage of HA.Method:1.Test molecular weight of HA (Mr_ HA ) by vis...Objective: Prepare cross-linked HA gels with higher mechanical stability, lower degradation velocity and desirable biocompatibility,so as to extend the usage of HA.Method:1.Test molecular weight of HA (Mr_ HA ) by viscosimetry;2.prepare cross-linked HA gels by DVS, GTA, DEC;3.discuss the cross-linking and degradation procedure;4.evaluate the biocompatibility of the best HA gels. Results:The mechanical stability and durability to degradation of HA-DVS gels are superior to those of other gels, and when HA:DVS = 40:1(g/g), at 35℃ and in 0.2 M NaOH solution, the HA-DVS gel shows the best mechanical stability, and its cytotoxicity reaches class I, hemolysis ratio is lower than 5%. Conclusion:Our HA-DVS gel can be used to prepare biologic scaffolds.展开更多
This paper is a summary to introduce thehigh tower structure design. These towers areapproximately 100 m high for large rivercrossing projects on 220 kV and 500 kVdesigned by the East China Electric PowerDesign lnstit...This paper is a summary to introduce thehigh tower structure design. These towers areapproximately 100 m high for large rivercrossing projects on 220 kV and 500 kVdesigned by the East China Electric PowerDesign lnstitute (ECEPDI) since 1958.The paper also introduces thecharacteristics, technical and economicparameters of the four typical towersdesigned by ECEPDI such as the concretechimney-type tower, steel tubular tower,guyed tower and compound angle steel tower.展开更多
文摘Plastic deformation of TiAI and TiAI-V intermetallic compounds has been studied by com- pression experiment at various temperatures and strain rates.Results show that the plastic deformation in distinct temperature range is principally controlled by the mechanisms of Peierls-Nabarro,cross slip and creep of dislocations.For TiAI-V alloy deformed at a range of 600—700 K,the negative strain rate dependence of flow stress was observed,i.e.,the more the plastic strain is.the more the negative dependence will be.A possible mechanism of the anomaly could be interpreted by thermal activation of dislocation cross slipping.The effects of temperature and strain rate on work-hardening exponent were also studied and discussed.
基金The Second Hospital of Tianjin Medical University,300211 Tianjin,China
文摘Objective: Prepare cross-linked HA gels with higher mechanical stability, lower degradation velocity and desirable biocompatibility,so as to extend the usage of HA.Method:1.Test molecular weight of HA (Mr_ HA ) by viscosimetry;2.prepare cross-linked HA gels by DVS, GTA, DEC;3.discuss the cross-linking and degradation procedure;4.evaluate the biocompatibility of the best HA gels. Results:The mechanical stability and durability to degradation of HA-DVS gels are superior to those of other gels, and when HA:DVS = 40:1(g/g), at 35℃ and in 0.2 M NaOH solution, the HA-DVS gel shows the best mechanical stability, and its cytotoxicity reaches class I, hemolysis ratio is lower than 5%. Conclusion:Our HA-DVS gel can be used to prepare biologic scaffolds.
文摘This paper is a summary to introduce thehigh tower structure design. These towers areapproximately 100 m high for large rivercrossing projects on 220 kV and 500 kVdesigned by the East China Electric PowerDesign lnstitute (ECEPDI) since 1958.The paper also introduces thecharacteristics, technical and economicparameters of the four typical towersdesigned by ECEPDI such as the concretechimney-type tower, steel tubular tower,guyed tower and compound angle steel tower.
