Backlund transformation, exact solitary wave solutions, nonlinear supperposi tion formulae and infinite conserved laws are presented by using TU-pattern. The algorithm involves wide applications for nonlinear evolutio...Backlund transformation, exact solitary wave solutions, nonlinear supperposi tion formulae and infinite conserved laws are presented by using TU-pattern. The algorithm involves wide applications for nonlinear evolution equations.展开更多
his paper deals with the phase trans formation of austenite to ferrite within the critical temperature region(between Ac1 and Ac3).The results show that the volume fraction of trans formation of ferrite formed isother...his paper deals with the phase trans formation of austenite to ferrite within the critical temperature region(between Ac1 and Ac3).The results show that the volume fraction of trans formation of ferrite formed isothermally from austenite is mainly varied with the austenitizing temperature.The higher the austenitizing temperature,the more volume fraction of the ferrite formed isothermally from austenite.Besides,the phase trans formation of austenite to ferrite within the critical temperature region was checked by austenitizing isothermal time.The volume fraction of ferrite formed isothermally from austenite within the critical temperature region for different isothermal time has heen examined experimen tally.The lglg(l-fv)-1 vs lgt relation does not follow the Avrami equation strictly and consists of two straight lines.展开更多
In this paper, an in situ metallographic video system was used to study the morphology in Cu-Zn-Al shape memory alloy (SMA) during thermal cycling phase tmnsforma-tion. There are seven different types of martensite mo...In this paper, an in situ metallographic video system was used to study the morphology in Cu-Zn-Al shape memory alloy (SMA) during thermal cycling phase tmnsforma-tion. There are seven different types of martensite morphology in Cu-Zn-Al SMA,i.e. plate, spean bamboo, noose, round-spot, line and dot-like martensites. During transformation and inverse-transformation, the thermoelastic martensites were rising and falling, growing and shrinking, splitting and merping. The growth patterns of thermoelastic martensite were divided into three types: fast growing, very slow ex-pansion and uniform automatic growth. Automatic growth appeared when ageing at a temperature below Ms. The result, for the first time, coofirmed Olson and Cohen,s suggestion that thermoelastic martensite may be automatically grown when ageing be-low Ms. With increasing numbers of thermal cycling, both the memory recovery ratio (% )and memory recoverp degradation (%) degraded logarithmically. The degrada-tion was steep in the initial stage and then became more and more gradual in the middle and the final stages caused by the stabilisation of martensite. In the initial stage, vacancies assumed the controlling role, while dislocations took the major role in other stages. The martensite transformation caused the intedeces to become bent and blurmd, but with increasing cycling numbers, the movements of interface had the same degradation effects as the memory recovery ratio curves. Under these conditions, we also found the martensites on one side of the intedece became reorientated and par-allel to the intedece. It was therefore concluded that the movement degradation of the interface and the appearance of bamboo like martensite induced the degradation of two way shape memory effect (TWMP).展开更多
Larger amount of austenite could be retained in an intercritically heat-treated bainite- transformed steel. The elongation and the strength-ductility balance of the steel could be enhanced considerably due to strain-i...Larger amount of austenite could be retained in an intercritically heat-treated bainite- transformed steel. The elongation and the strength-ductility balance of the steel could be enhanced considerably due to strain-induced martensite transformation and transformation- induced plasticity (TRIP) of retained austenite. The effects of test temperature and strain rate on the mechanical properties and strain induced transformation behavior of retained austenite in the steel were investigated. Total elongation and strength-ductility balance of the specimen reached maximum when it strained at a strain rate of 2.8×10-4s-1 and at 350℃. The relation between test temperature and tensile properties showed the same tendency at three kinds of strain rates. Flow stress increased considerably with decreasing the strain rate.展开更多
The continuous input of various emerging contaminants(ECs)has inevitably introduced large amounts of transformation products(TPs)in natural and engineering water scenarios.Structurally similar to the precursor species...The continuous input of various emerging contaminants(ECs)has inevitably introduced large amounts of transformation products(TPs)in natural and engineering water scenarios.Structurally similar to the precursor species,the TPs are expected to possess comparative,if not more serious,environmental properties and risks.This review summarizes the state-of-the-art knowledge regarding the integrated risk assessment frameworks of TPs of ECs,mainly involving the exposure-and effectdriven analysis.The inadequate information within existing frameworks that was essential and critical for developing a better risk assessment framework was discussed.The main strategic improvements include(1)non-targeted product analysis in both laboratory and field samples,(2)omics-based highthroughput toxicity assessment,(3)multichannel-driven mode of action in conjugation with effectdirected analysis,and(4)machine learning technology.Overall,this review provides a concise but comprehensive insight into the optimized strategy for evaluating the environmental risks and screening the key toxic products from the cocktail mixtures of ECs and their TPs in the global water cycle.This facilitates deciphering the mode of toxicity in complex chemical mixtures and prioritizing the regulated TPs among the unknown products,which have the potential to be considered a class of novel"ECs"ofgreatconcern.展开更多
文摘Backlund transformation, exact solitary wave solutions, nonlinear supperposi tion formulae and infinite conserved laws are presented by using TU-pattern. The algorithm involves wide applications for nonlinear evolution equations.
文摘his paper deals with the phase trans formation of austenite to ferrite within the critical temperature region(between Ac1 and Ac3).The results show that the volume fraction of trans formation of ferrite formed isothermally from austenite is mainly varied with the austenitizing temperature.The higher the austenitizing temperature,the more volume fraction of the ferrite formed isothermally from austenite.Besides,the phase trans formation of austenite to ferrite within the critical temperature region was checked by austenitizing isothermal time.The volume fraction of ferrite formed isothermally from austenite within the critical temperature region for different isothermal time has heen examined experimen tally.The lglg(l-fv)-1 vs lgt relation does not follow the Avrami equation strictly and consists of two straight lines.
文摘In this paper, an in situ metallographic video system was used to study the morphology in Cu-Zn-Al shape memory alloy (SMA) during thermal cycling phase tmnsforma-tion. There are seven different types of martensite morphology in Cu-Zn-Al SMA,i.e. plate, spean bamboo, noose, round-spot, line and dot-like martensites. During transformation and inverse-transformation, the thermoelastic martensites were rising and falling, growing and shrinking, splitting and merping. The growth patterns of thermoelastic martensite were divided into three types: fast growing, very slow ex-pansion and uniform automatic growth. Automatic growth appeared when ageing at a temperature below Ms. The result, for the first time, coofirmed Olson and Cohen,s suggestion that thermoelastic martensite may be automatically grown when ageing be-low Ms. With increasing numbers of thermal cycling, both the memory recovery ratio (% )and memory recoverp degradation (%) degraded logarithmically. The degrada-tion was steep in the initial stage and then became more and more gradual in the middle and the final stages caused by the stabilisation of martensite. In the initial stage, vacancies assumed the controlling role, while dislocations took the major role in other stages. The martensite transformation caused the intedeces to become bent and blurmd, but with increasing cycling numbers, the movements of interface had the same degradation effects as the memory recovery ratio curves. Under these conditions, we also found the martensites on one side of the intedece became reorientated and par-allel to the intedece. It was therefore concluded that the movement degradation of the interface and the appearance of bamboo like martensite induced the degradation of two way shape memory effect (TWMP).
基金the National Natural Science Foundation of China(No.50334010)the Doctor Degree Thesis Subsidization Item of Northeastern Universiry(No.200302).
文摘Larger amount of austenite could be retained in an intercritically heat-treated bainite- transformed steel. The elongation and the strength-ductility balance of the steel could be enhanced considerably due to strain-induced martensite transformation and transformation- induced plasticity (TRIP) of retained austenite. The effects of test temperature and strain rate on the mechanical properties and strain induced transformation behavior of retained austenite in the steel were investigated. Total elongation and strength-ductility balance of the specimen reached maximum when it strained at a strain rate of 2.8×10-4s-1 and at 350℃. The relation between test temperature and tensile properties showed the same tendency at three kinds of strain rates. Flow stress increased considerably with decreasing the strain rate.
基金the Natural Science Foundation of China-Joint Fund Project(No.U2005206)the Xiamen Municipal Bureau of Science and Technology(No.YDZX20203502000003)the support of the President Research Funds from Xiamen University(No.20720210081).
文摘The continuous input of various emerging contaminants(ECs)has inevitably introduced large amounts of transformation products(TPs)in natural and engineering water scenarios.Structurally similar to the precursor species,the TPs are expected to possess comparative,if not more serious,environmental properties and risks.This review summarizes the state-of-the-art knowledge regarding the integrated risk assessment frameworks of TPs of ECs,mainly involving the exposure-and effectdriven analysis.The inadequate information within existing frameworks that was essential and critical for developing a better risk assessment framework was discussed.The main strategic improvements include(1)non-targeted product analysis in both laboratory and field samples,(2)omics-based highthroughput toxicity assessment,(3)multichannel-driven mode of action in conjugation with effectdirected analysis,and(4)machine learning technology.Overall,this review provides a concise but comprehensive insight into the optimized strategy for evaluating the environmental risks and screening the key toxic products from the cocktail mixtures of ECs and their TPs in the global water cycle.This facilitates deciphering the mode of toxicity in complex chemical mixtures and prioritizing the regulated TPs among the unknown products,which have the potential to be considered a class of novel"ECs"ofgreatconcern.
