The utilization of reclaimed asphalt pavement(RAP)in asphalt mixtures has gained momentum in recent years,yet concerns persist regarding the long-term performance and binder properties of high RAP content mixtures.To ...The utilization of reclaimed asphalt pavement(RAP)in asphalt mixtures has gained momentum in recent years,yet concerns persist regarding the long-term performance and binder properties of high RAP content mixtures.To overcome these challenges,rejuvenators have emerged as a promising solution to enhance the properties of aged asphalt binders and improve the overall performance of asphalt mixtures.This paper provides a comprehensive state-of-the-art review of rejuvenator technology and its potential to enhance the performance and sustainability of asphalt pavements.Rejuvenators are additives used to restore the properties of aged asphalt binders,particularly when incorporating high percentages of RAP.The performance of these additives varies based on their origin,and different methods can be used to analyze the rejuvenation process.Since proper specifications for rejuvenators are not available,blending charts are used to determine the optimum dosage of rejuvenators.However,proper blending must be achieved to maximize results and reduce the effect of black rock.Laboratory tests and some field performance studies on rejuvenated aged asphalt binders and RAP mixtures have shown improved or similar performance compared to virgin materials.Additionally,the use of rejuvenators has been observed to reduce construction costs,suggesting that this is a cost-effective technology for asphalt pavements.While rejuvenators show promise in improving the performance of pavements with recycled materials,challenges remain regarding optimization,long-term durability,and environmental effects.This review paper also identifies key areas for future research,including life-cycle cost analyses,comprehensive environmental impact assessments,and long-term field performance monitoring.展开更多
The“longevity protein”SIRT5 could hold the key to delaying age-related muscle decline.A study led by researchers from the Institute of Zoology(IOZ)of the Chinese Academy of Sciences and Capital Medical University in...The“longevity protein”SIRT5 could hold the key to delaying age-related muscle decline.A study led by researchers from the Institute of Zoology(IOZ)of the Chinese Academy of Sciences and Capital Medical University in Beijing reveals that SIRT5 mitigates skeletal muscle aging by blocking pro-inflammatory pathways.Published in Nature Metabolism on March 14,2025,the work identifies SIRT5’s interaction with protein kinase TBK1 as critical to preserving muscle mass and function.展开更多
The pressing demand for sustainable advancements in road infrastructure has catalyzed extensive research into environmentally conscious alternatives for the maintenance and restoration of asphalt concrete pavements.Th...The pressing demand for sustainable advancements in road infrastructure has catalyzed extensive research into environmentally conscious alternatives for the maintenance and restoration of asphalt concrete pavements.This paper offers a comprehensive review and analysis of bio-based rejuvenators as a promising avenue for enhancing the longevity and sustainability of asphalt.Through a multifaceted exploration,it delves into various aspects of this innovative approach.Providing a thorough overview of bio-based rejuvenators,the study highlights their renewable and environmentally friendly characteristics.It conducts an in-depth examination of a wide spectrum of bio-derived materials,including vegetable oils,waste-derived bio-products,and biopolymers,through a comprehensive survey.The paper evaluates how bio-based rejuvenators enhance aged asphalt binders and mixes,effectively mitigating the adverse impacts of aging.Furthermore,it investigates how these rejuvenators address environmental concerns by identifying compatibility issues,assessing long-term performance,and evaluating economic feasibility.Finally,the paper outlines potential advancements and research pathways aimed at optimizing the utilization of bio-based rejuvenators in asphalt concrete,thereby contributing to the sustainable evolution of road infrastructure.展开更多
A composite rejuvenator was used for the rejuvenation of aged asphalt in comparison with the common rejuvenator. The effects of the rejuvenators on the performance and microstructure of the aged asphalt were investiga...A composite rejuvenator was used for the rejuvenation of aged asphalt in comparison with the common rejuvenator. The effects of the rejuvenators on the performance and microstructure of the aged asphalt were investigated by physical properties tests, dynamic shear rheometer and atomic force microscopy. The results indicate that the physical and rheological properties of the aged asphalt are restored more significantly by the composite rejuvenator than the common rejuvenator, which can be ascribed to the effective recovery of microstmcture of the aged asphalt. The composite rejuvenator has the potential to be used for the rejuvenation of severely aged asphalt since it can restore the colloidal structure of the aged asphalt effectively through composition regulation and chemical reactions between the composite rejuvenator and asphaltenes.展开更多
The binder properties were determined in accordance with Chinese standard such as ductility test, which allowed to measure the distance in centimeters that a standard briquette of asphalt had been stretched before bre...The binder properties were determined in accordance with Chinese standard such as ductility test, which allowed to measure the distance in centimeters that a standard briquette of asphalt had been stretched before breaking. Then, penetration test was carried out in order to know some properties of the asphalt, which are the hardness and the softness. Finally, softening point test was carried out in order to determine the temperature at which the bitumen attains a particular degree of softening under the specification of the test. According to Chinese standard for performance tests, firstly, Marshall test was carried out in order to measure the theoretical density, air voids, voids filled with asphalt, stability, flow, and voids in mineral aggregate of asphalt specimens. Secondly, Freeze-thaw splitting test was carried out in order to determine Splitting strength ratio. Finally, dynamic stability (rutting) test was carried out to determine average dynamic stability. Beside the tests carried out, the gradation of the extracted aggregate in accordance with American Association of State Highway and Transportation Officials was carried out to determine the dimensions of the particles weight distribution. Furthermore, both the percentage of recycled asphalt pavement materials and binder in mixture were determined to know how much of the new material during the mixture was needed. However, two specimens were used to evaluate the performance of recycled asphalt pavement materials. One specimen of recycled asphalt pavement materials was ten years old, and another one of recycled asphalt pavement materials was five years old. The results show that the conditions of the environment such as moisture, temperature, and age, decrease the ductility and penetration properties of binder when increase the softening point property of binder. Then the gradation of recycled asphalt pavement aggregate is of the required values to reuse in the mixture, while the flow ratio, the splitting strength ratio, and the dynamic stability ratio, are less than the required value test. With regard to the properties of mixture of recycled asphalt pavement material binder with rejuvenator, the results show that when the penetration and ductility versus percentage of rejuvenator increase, softening point versus percentage of rejuvenator decreases. Also, when the bitumen and rejuvenator percentage increase, the air voids decrease. Consequently, voids filled with asphalt and voids in the mineral aggregate increase. Moreover, the theoretical density and stability values decrease in a mixture containing four-point fifty percent to six percent of bitumen and rejuvenator, whereas the flow values increase. More interestingly, with four percent to four-point fifty percent mixture ratio of bitumen and rejuvenator, density, stability, and flow values increase. The splitting strength ratio values of mixtures and the dynamic stability test (rutting test) values of mixtures with forty percent of specimen one and specimen two respectively are greater than the required value of the standard test. In addition, the high percentage of rejuvenator increases the rut of pavement, in the same manner, the low percentage of rejuvenator induces low rut. In conclusion, the binder content from recycled materials without rejuvenator seems not be sufficient to be reused on the new pavement while the aged recycled material seems to be performed better than no aged recycled material with rejuvenator into bitumen. Then, the rejuvenator can influence the bitumen properties and performance of the pavement. Finally, the pavement made by only recycled pavement materials as a base layer appears to be more economical but cannot be more effective than the pavement made by mixture of new and recycled pavement materials as a base layer.展开更多
The physical performance of recycled asphalt was used as the main evaluation index to study the optimal range of a self-made rejuvenator.Through the penetration,viscosity and gel permeation chromatography(GPC)tests,th...The physical performance of recycled asphalt was used as the main evaluation index to study the optimal range of a self-made rejuvenator.Through the penetration,viscosity and gel permeation chromatography(GPC)tests,the diffusion degree of the rejuvenator under different temperatures and time process was analyzed,and the diffusion efficiency of the rejuvenator was evaluated from the macro and micro perspective.The regeneration mechanism of the rejuvenator in the aged asphalt was also analyzed using the Fourier transform infrared spectroscopy(FTIR),scanning electron microscope(SEM)and chemical composition tests.The research results showed that the optimum rejuvenator content was about 3%.Higher temperature and longer time were beneficial to improving the permeability and diffusion of the rejuvenator.During the aging process,the light components were reduced,and more macromolecular asphaltenes were generated as well as a large number of carbonyl and sulfoxide.After diffusion and regeneration,the light components in the asphalt were supplemented,the wrinkles and gullies of the aged asphalt were almost improved to the surface state of the matrix asphalt.展开更多
Rejuvenators are products designed to restore original properties to oxidized asphalt binders by restoring the original ratio of asphaltenes to maltenes. But,for a rejuvenator to be successful,it must penetrate the pa...Rejuvenators are products designed to restore original properties to oxidized asphalt binders by restoring the original ratio of asphaltenes to maltenes. But,for a rejuvenator to be successful,it must penetrate the pavement surface. Besides,application of a rejuvenator will also reduce the skid resistance of the pavement. To solve this,these rejuvenators can be encapsulated and mixed in asphalt concrete. Once the stress in the capsules reaches a certain threshold,the particles break and the rejuvenator is released,giving back the original properties of the pavement. The objective of this paper is to show how these capsules behave and define the most appropriate testing methods to find their effect on asphalt concrete. For this,two different types of rejuvenators will be encapsulated and their effect on the properties of the capsules investigated. Besides,the release mechanisms of the capsules will be unravelled.展开更多
Rejuvenator diffusing into aged bitumen was evaluated by determining penetration and chemical components of aged bitumen with rejuvenator coat before and after diffusing experiment. Effects of temperature, time and vi...Rejuvenator diffusing into aged bitumen was evaluated by determining penetration and chemical components of aged bitumen with rejuvenator coat before and after diffusing experiment. Effects of temperature, time and viscosity of rejuvenator on the diffusing ability of rejuvenator into aged bitumen were investigated. Results indicated that the diffusing ability of rejuvenator into aged bitumen could be enhanced with the increasing of temperature and time, however, the diffusing of rejuvenator into aged bitumen would be restricted due to the volatilization of light component and aging of rejuvenator under high temperature （over 170 ℃）. Rejuvenator with low viscosity diffused into aged bitumen more easily.展开更多
The inherent self-healing ability of asphalt is insufficient and fails to timely repair the cracks due to the combined effect of temperature variation,air oxidation,ultraviolet exposure and traffic loading.Rejuvenator...The inherent self-healing ability of asphalt is insufficient and fails to timely repair the cracks due to the combined effect of temperature variation,air oxidation,ultraviolet exposure and traffic loading.Rejuvenator encapsulation based on self-healing asphalt is a green sustainable preventive maintenance technology for asphalt pavement.During the last decade,rejuvenator encapsulation for asphalt self-healing has been a research hotspot and calcium alginate hydrogels encapsulating rejuvenator is a promising self-healing technology.Hence,this review sheds light on the recent advances of calcium alginate hydrogels encapsulating asphalt rejuvenator including selfhealing capsules and fibers.The synthesis methods of calcium alginate capsules and fibers containing rejuvenator were elaborately introduced,and their surface morphology,interior structure,mechanical strength,thermal stability,rejuvenator content,distribution and survival in asphalt materials were systematically analyzed.Besides,the effect of capsules and fiber on the mechanical property and pavement performance of asphalt concrete were explored.Additionally,a comprehensive review about the effect of calcium alginate capsules and fibers on selfhealing ability of asphalt materials were presented,and the rejuvenator release mechanism and release ratio of them in asphalt mixtures were expounded.In a nutshell,this review aims at highlighting the current research achievements on alginate capsules and fibers containing rejuvenator in asphalt materials,and inspiring enhanced self-healing methods for smart and sustainable maintenance of asphalt pavement.展开更多
Reclaimed asphalt pavement (RAP) is a byproduct of milling flexible pavements and is typically used in recycling initiatives worldwide. The excessive dosage of RAP can have negative effects on asphalt mixture properti...Reclaimed asphalt pavement (RAP) is a byproduct of milling flexible pavements and is typically used in recycling initiatives worldwide. The excessive dosage of RAP can have negative effects on asphalt mixture properties unless it goes through a rejuvenation process. Waste cooking oil (WcO) is one of the green solutions for rejuvenating aged binder in asphaltic concrete, and, like virgin asphalt binder, it contains light oil components. This review article offers current information on WCO's rejuvenating performance and the effect of its variable dosage on binders of varying grades. Several physical and rheological characteristics were investigated, and an appropriate spectrum of reported data was defined for the virgin and rejuvenated binders to ascertain the distinctive characteristics.Additionally, the effect of WCO on binders' asphaltene content, molecular structure,microscopic morphology, mechanical properties, and aging indices was discussed. In the high point of this review, a data range is developed for rejuvenated aged binders based on different properties prior to making a better prediction under different circumstances.Moreover, an optimum value is discussed suggesting the best balance between fatigue performance and rutting resistance. The aged binders modified with WCO exhibit better microchemical properties and particle orientation, with enhanced surface area and coating with aggregates, imitating the micropattern of conventional asphalt binder. Moreover, this review further discusses the economic and ecological aspects of WCO usage as a green asphalt binder rejuvenator.展开更多
Asphalt binder plays a significant role in the performance of asphalt pavement.However,due to the limited availability of crude oil and the increasing cost of asphalt,alternatives are being investigated.Reclaimed asph...Asphalt binder plays a significant role in the performance of asphalt pavement.However,due to the limited availability of crude oil and the increasing cost of asphalt,alternatives are being investigated.Reclaimed asphalt pavement(RAP)provides a sustainable solution for the increasing demand of asphalt.However,the amount of RAP which can be utilized in asphalt mixtures is limited due to production and performance issues.Incorporation of high RAP content calls for rejuvenators,which rejuvenate the aged binder and increases the degree of blending.Among various rejuvenators,waste cooking oil(WCO)is gaining increased attention due to its availability and concern towards environmental pollution.When combined in proper proportions with RAP,WCO is a potential rejuvenator,which restores the properties of aged binder to that of unaged asphalt binder.This addresses two problems simultaneously and can greatly benefit the economy and environment.This study focuses on the viscoelastic and rheological properties of the rejuvenated binder with WCO and RAP.The rheological properties are evaluated using frequency sweep test by assessing the complex shear modulus and rutting parameter of different binders.The vis-coelastic properties are studied using multiple stress creep recovery(MSCR)test.The data of the MSCR test are analyzed with the Burger model to understand the viscoelastic prop-erties of the rejuvenated RAP binder.For each of 75%,60%,and 45%RAP,three different oil proportions are selected,and the optimum WCO content is identified.The study concludes that higher RAP content results in lower viscous strain and higher elastic strain,whereas after mixing higher WCO,the viscous strain increases,and the elastic strain decreases.Hence,it is crucial to mix WCO and RAP in the optimum ratio to obtain the desired rheo-logical and viscoelastic properties.展开更多
The use of reclaimed asphalt pavement （RAP） in new hot mix asphalt （HMA） by means of hot recycling techniques generates the advantage linked to the exploitation of both lytic and bituminous component, consequently...The use of reclaimed asphalt pavement （RAP） in new hot mix asphalt （HMA） by means of hot recycling techniques generates the advantage linked to the exploitation of both lytic and bituminous component, consequently leading to the decrease of both virgin aggregates and bitumen supplying. However, many agencies and public administration authorise RAP percentages ranges from 10% to 30% in hot recycling. The main reason for such a low amount of allowable RAP content is related to the aged bitumen contained in the RAP materials, which is more brittle than a virgin bitumen leading to a final mixture more susceptible to fatigue, thermal and reflection cracking. The use of rejuvenators has the potential to restore rheology and chemical components of aged RAP bitumen, thus allowing a significant increase in the amount of RAP to be properly implemented in HMA. The experimental investigation is described in this paper and carried out through a dynamic shear rheometer （DSR） which provides the rheological characterisation of a paving grade bitumen during its overall service life including its reuse in hot recycling by adopting different rejuvenators. Results show that rejuvenators modify bitumen chemistry and consequently rheology by enhancing the viscous response. Moreover, it was observed that oxidation is less harmful, in terms of stiffness increase, on the 50/50 aged bitumen - virgin bitumen blends （rejuvenated or not） than on the virgin bitumen. Moreover, the addition of a rejuvenator in a bituminous blend containing 50% of bitumen reactivated from RAP could lead to a corresponding composite bituminous phase less subjected to ageing phenomena and even less stiff at the end of service life than the associated virgin bitumen alone.展开更多
Prompting high content of reclaimed asphalt pavement(RAP) to be used in road building and maintenance has drawn great attention. The application of rejuvenators is an efficient way to ensure the performance of recycle...Prompting high content of reclaimed asphalt pavement(RAP) to be used in road building and maintenance has drawn great attention. The application of rejuvenators is an efficient way to ensure the performance of recycled asphalt mixtures. However, as various types of rejuvenators emerging, limited understanding about rejuvenation poses challenges to put effective ones into use. For precisely evaluating the performance of rejuvenators, plenty of studies were conducted to ascertain the fundamental mechanism of rejuvenating from the microscopic view. This paper provides an overview of studies focusing on the change inside asphalt after adding rejuvenators. Chemical compositions of rejuvenators were collected as basic information. Both laboratorial experiments and molecular dynamic simulations were investigated to not only compare the effectiveness of several rejuvenators but also explain the rejuvenating mechanism. Finally, functional groups of rejuvenator structures were comprehensively examined to provide global understanding about how chemical compositions influence the efficacy of rejuvenators. This review highlights that the essential capacity of a true rejuvenator is to disturb asphaltene agglomerations. Besides, the molecular structures of rejuvenators will not only affect their deagglomerating abilities but also the performances of diffusion and durability. It has been found that gel-permeation chromatography(GPC) analysis is effective in evaluating the performance of rejuvenators, while Fourier transform infrared spectroscopy(FT-IR) and SARA(saturates, aromatics, resins and asphaltenes) analysis are only suitable for assessing asphalt oxidization. In addition, comparing some tests can only detect changes, molecular dynamic simulation can reveal the mechanism both of data and vision. The results of this work can provide comprehensive knowledge for the evaluation and development of rejuvenators.展开更多
This article presents development of a novel self-healing technology for asphalt pave- ments, where asphalt binder rejuvenator is encapsulated within the compartmented alginate fibres. The key objective of the study w...This article presents development of a novel self-healing technology for asphalt pave- ments, where asphalt binder rejuvenator is encapsulated within the compartmented alginate fibres. The key objective of the study was to optimise the compartmented alginate fibre design, i.e., maximising amount of rejuvenator encapsulated within the fibre. The results demonstrate that optimum rejuvenator content in the alginate fibre is of 70：B0 rejuvenator/alginate ratio. The fibres are of sufficient thermal and mechanical strength to survive harsh asphalt mixing and compaction processes. Furthermore, results illustrate that zeer open asfalt beton （ZOAB） asphalt mix containing 5% of 70：30 rejuvenator/alginate ratio compartmented alginate fibres has higher strength, stiffness and better healing properties in comparison to the control asphalt mix, i.e., mix without fibres, and mix containing fibres with lower rejuvenator content. These results show that compartmented alginate fibres encapsulating bitumen rejuvenator present a promising new approach for the development of self-healing asphalt pavement systems.展开更多
The objective of this paper is to comprehensively review the research progress of bio-oil properties and hot rejuvenation behavior and mechanism to aged asphalt.The preparation process,composition characteristics of b...The objective of this paper is to comprehensively review the research progress of bio-oil properties and hot rejuvenation behavior and mechanism to aged asphalt.The preparation process,composition characteristics of bio-oils and their component correspondence with petroleum asphalt were compared.The diffusion and fusion effects of various bio-oils in aged asphalt were introduced.Bio-oil cannot be used as a direct alternative of petroleum asphalt,but it has the potential to effectively rejuvenate aged asphalt binders due to the component similarity with petroleum asphalt and good diffusion properties.For the asphalt rejuvenation,the functionalization treatment methods of bio-oil were discussed such as purification,composition modification and component conversion.The active groups and derivatives in bio-oil can be converted into the missing components of the aged binder through phenolate,grafting,polycondensation,resinifying,but the conversion process and mechanism are still unclear.From the perspectives of diffusion behavior,components regulation,dissolving asphaltene and micro-rejuvenation effect,the rejuvenation behavior and mechanism of bio-oil on aged asphalt were elaborated,and the effects of various types of bio-oil and aged asphalt on rejuvenation behavior were analyzed.The preparation process and dosage of bio-rejuvenator were summarized.The rejuvenation effects of bio-oil on aged asphalt were comprehensively investigated from the aspects of high and low temperature performances,rheological properties,microstructure and chemical composition of bio-rejuvenated asphalt binders.Finally,the limitations of bio-oil used as asphalt rejuvenators were discussed,and future research directions were prospected,which can provide reference and theoretical basis for the development of high-performance bio-oil rejuvenating agents and the engineering application of bio-oil to improve the properties of aged asphalt materials.展开更多
Technological advancements have produced sustainable approaches to pavement preservation and reconstruction procedures.Specific recycling processes are being developed to reuse the asphalt concrete guaranteeing costs ...Technological advancements have produced sustainable approaches to pavement preservation and reconstruction procedures.Specific recycling processes are being developed to reuse the asphalt concrete guaranteeing costs and environmental effects reduction.Reclaimed asphalt pavement(RAP)is the material worldwide used in the road construction sector to ensure the sustainability of asphalt pavement.RAP employment percentages in asphalt concrete layers are increasing.The development of cold mix asphalt(CMA)recycling technique including high amount of RAP is becoming popular especially for localized patching and potholes.Wearing course layers designed for bicycle lanes realized with 100%RAP and CMA technologies are presented in this research.Two cycle paths rehabilitated with different construction technologies in-plant and in-place recycling techniques are compared by performing a trial field and laboratory analysis on compacted and cored samples.An innovative rejuvenator used as additive specifically designed for CMAs is added as rejuvenator in both RAPs.The main goal is to determine the frictional,physical and mechanical characteristics of solutions produced by using high quantity of recycled materials.British pendulum tester(BPT)and Micro GripTester are applied to assess skid performance and indirect tensile strength test(ITS)and Marshall stability is performed to analyse the mechanical behaviour.RAPs skid resistance and physical-mechanical properties provide positive outcomes with viable characteristics for urban soft-mobility solutions.The innovative machine used in the in-place technique demonstrated excellent performance in terms of milling and mixing,representing a valid alternative for repaving applications in the urban context.展开更多
The performance evaluation and chemical property analysis of the recycled warm mix asphalt （RWMA） binders containing 100% artificial reclaimed asphalt （ RA） are presented, and the combined effects of different p...The performance evaluation and chemical property analysis of the recycled warm mix asphalt （RWMA） binders containing 100% artificial reclaimed asphalt （ RA） are presented, and the combined effects of different percentages of the rejuvenator and warm mix additive （WMA） additives on RWMA binders are analyzed through laboratory tests. Three types of WMA additives ad one commercial rejuvenator named GST were selected to restore the artificial RA. The laboratory performace tests including the penetration test, softening test ad rotary, viscosity （RV） test were carried out. In addition, the Fourier transform infrared spectroscopy （FTIR） test was performed to explore the chemical property of RWMA binders. The results of the performance tests indicate that the rejuvenator GST has the ability to restore the artificial RA; choosing the optimum content of WMA additives and rejuvenator is the key to restoring 100% artificial RA, since the combined effects of them play an important role in determining the basic laboratory performance of RWMA binders. The FTIR tests show that the process of recycling mainly adjusts the chemical component of aged asphalt and no remarkable change is observed in the FTI1R spectra of RWMA binders in terms of chemical functional groups with the introduction of WMA additives.展开更多
Recent attention has been directed towards tailoring the internal structure and enhancing the plasticity of metallic glasses(MGs)via rejuvenation treatments.This work aims to comprehensively review the various approac...Recent attention has been directed towards tailoring the internal structure and enhancing the plasticity of metallic glasses(MGs)via rejuvenation treatments.This work aims to comprehensively review the various approaches and underlying mechanisms of inducing rejuvenation in MGs,including thermal-activated methods for deep-cooling cycling treatments and annealing-induced regeneration,mechanical-driven methods of pre-elastic loading and plastic deformation,thermo-mechanically coupled methods for thermo-mechanical creep and thermoplastic forming,and irradiation-induced rejuvenation.Additionally,strategies such as gradient rejuvenation for promoting a favorable distribution of free volume gradients to deflect shear bands are discussed for enhancing plasticity.Finally,the review delves into the challenges and prospects associated with advancing the development of MGs exhibiting high plasticity at ambient conditions.This review is anticipated to contribute to fostering a systematic understanding of the diverse methods and mechanisms employed to enhance the plasticity of MGs via rejuvenation treatments.展开更多
Aging,as an inherent stage of life processes,has always been a core research focus in life sciences.Current studies confirm that the accumulation of intracellular molecular damage is a key driver of aging.As protectiv...Aging,as an inherent stage of life processes,has always been a core research focus in life sciences.Current studies confirm that the accumulation of intracellular molecular damage is a key driver of aging.As protective structures at chromosome ends,telomeres exhibit direct correlations between their length and stability and cellular aging processes,disease risks,and lifespan.This article systematically reviews the structural functions of telomeres and their relationship with aging,with particular emphasis on telomere rejuvenation strategies based on electromagnetic radiation techniques.Key experimental approaches include Gavich's mitotic radiation,Composite Wave Resonator(CWRT),and modern telomere length intervention trials.By synthesizing the latest domestic and international research findings,this paper analyzes the feasibility and limitations of these technologies while exploring their potential applications in anti-aging research,providing theoretical references for future studies.展开更多
Creep is one of the most typical failure modes for the turbine blades of an aero-engine.The microstructure of the turbine blades after long-term service can be adjusted by rejuvenation heat treatment(RHT)to restore it...Creep is one of the most typical failure modes for the turbine blades of an aero-engine.The microstructure of the turbine blades after long-term service can be adjusted by rejuvenation heat treatment(RHT)to restore its creep properties.In this work,a series of RHT experiments were carried out on a directionally solidified(DS)nickel-based superalloy under different solution temperatures and primary aging temperatures based on the standard heat treatment(SHT)process parameters to investigate the mechanism of temperature influence on DS's microstructure after RHT.It is indicated that a more uniform microstructure can be obtained under higher solution temperatures and lower primary aging temperatures compared to the SHT process.Furthermore,by employing the image processing methods to quantify microstructural parameters,a comprehensive indicator parameter for the RHT effect(marked as Prej)was proposed to characterize the effects of RHT on DS superalloy's microstructure and creep property combined with the entropy weight method.Based on this,a regression model to describe the relationship between RHT process parameters and Prej was constructed by using the response surface methodology(RSM).It is revealed that the optimal solution temperature and primary aging temperature for this DS superalloy are 1283°C and 1095°C,respectively.Then the conclusion was validated through complete creep experiments on the DS superalloy,which showed the creep life after RHT reaches 95.5%of the SHT specimen,and the total life has increased by 20.6%.展开更多
基金the Office of Research&Economic Development and Department of Civil,Coastal and Environmental Engineering at University of South Alabama for the support.
文摘The utilization of reclaimed asphalt pavement(RAP)in asphalt mixtures has gained momentum in recent years,yet concerns persist regarding the long-term performance and binder properties of high RAP content mixtures.To overcome these challenges,rejuvenators have emerged as a promising solution to enhance the properties of aged asphalt binders and improve the overall performance of asphalt mixtures.This paper provides a comprehensive state-of-the-art review of rejuvenator technology and its potential to enhance the performance and sustainability of asphalt pavements.Rejuvenators are additives used to restore the properties of aged asphalt binders,particularly when incorporating high percentages of RAP.The performance of these additives varies based on their origin,and different methods can be used to analyze the rejuvenation process.Since proper specifications for rejuvenators are not available,blending charts are used to determine the optimum dosage of rejuvenators.However,proper blending must be achieved to maximize results and reduce the effect of black rock.Laboratory tests and some field performance studies on rejuvenated aged asphalt binders and RAP mixtures have shown improved or similar performance compared to virgin materials.Additionally,the use of rejuvenators has been observed to reduce construction costs,suggesting that this is a cost-effective technology for asphalt pavements.While rejuvenators show promise in improving the performance of pavements with recycled materials,challenges remain regarding optimization,long-term durability,and environmental effects.This review paper also identifies key areas for future research,including life-cycle cost analyses,comprehensive environmental impact assessments,and long-term field performance monitoring.
文摘The“longevity protein”SIRT5 could hold the key to delaying age-related muscle decline.A study led by researchers from the Institute of Zoology(IOZ)of the Chinese Academy of Sciences and Capital Medical University in Beijing reveals that SIRT5 mitigates skeletal muscle aging by blocking pro-inflammatory pathways.Published in Nature Metabolism on March 14,2025,the work identifies SIRT5’s interaction with protein kinase TBK1 as critical to preserving muscle mass and function.
基金the Swedish Research Council for Sustainable Development FORMAS(grant 2021-00527)Wangjie Wu acknowledges the scholarship funding of the CSC-KTH program.
文摘The pressing demand for sustainable advancements in road infrastructure has catalyzed extensive research into environmentally conscious alternatives for the maintenance and restoration of asphalt concrete pavements.This paper offers a comprehensive review and analysis of bio-based rejuvenators as a promising avenue for enhancing the longevity and sustainability of asphalt.Through a multifaceted exploration,it delves into various aspects of this innovative approach.Providing a thorough overview of bio-based rejuvenators,the study highlights their renewable and environmentally friendly characteristics.It conducts an in-depth examination of a wide spectrum of bio-derived materials,including vegetable oils,waste-derived bio-products,and biopolymers,through a comprehensive survey.The paper evaluates how bio-based rejuvenators enhance aged asphalt binders and mixes,effectively mitigating the adverse impacts of aging.Furthermore,it investigates how these rejuvenators address environmental concerns by identifying compatibility issues,assessing long-term performance,and evaluating economic feasibility.Finally,the paper outlines potential advancements and research pathways aimed at optimizing the utilization of bio-based rejuvenators in asphalt concrete,thereby contributing to the sustainable evolution of road infrastructure.
基金Funded by the National High Technology Research and Development Program of China(863 Program)(No.2013AA031602)the Program for New Century Excellent Talents in University(No.NCET-10-0277)+1 种基金the Key Program for International Science and Technology Cooperation Projects of Shaanxi province(No.2012KW-09)the Doctoral Program Foundation of Institutions of Higher Education of China Research Fund for the Doctoral Program of Higher Education of China(No.20120205120010)
文摘A composite rejuvenator was used for the rejuvenation of aged asphalt in comparison with the common rejuvenator. The effects of the rejuvenators on the performance and microstructure of the aged asphalt were investigated by physical properties tests, dynamic shear rheometer and atomic force microscopy. The results indicate that the physical and rheological properties of the aged asphalt are restored more significantly by the composite rejuvenator than the common rejuvenator, which can be ascribed to the effective recovery of microstmcture of the aged asphalt. The composite rejuvenator has the potential to be used for the rejuvenation of severely aged asphalt since it can restore the colloidal structure of the aged asphalt effectively through composition regulation and chemical reactions between the composite rejuvenator and asphaltenes.
基金Funded by the Technology Research and Development Plan Program of Heilongjiang Province(No.GA19A501)。
文摘The binder properties were determined in accordance with Chinese standard such as ductility test, which allowed to measure the distance in centimeters that a standard briquette of asphalt had been stretched before breaking. Then, penetration test was carried out in order to know some properties of the asphalt, which are the hardness and the softness. Finally, softening point test was carried out in order to determine the temperature at which the bitumen attains a particular degree of softening under the specification of the test. According to Chinese standard for performance tests, firstly, Marshall test was carried out in order to measure the theoretical density, air voids, voids filled with asphalt, stability, flow, and voids in mineral aggregate of asphalt specimens. Secondly, Freeze-thaw splitting test was carried out in order to determine Splitting strength ratio. Finally, dynamic stability (rutting) test was carried out to determine average dynamic stability. Beside the tests carried out, the gradation of the extracted aggregate in accordance with American Association of State Highway and Transportation Officials was carried out to determine the dimensions of the particles weight distribution. Furthermore, both the percentage of recycled asphalt pavement materials and binder in mixture were determined to know how much of the new material during the mixture was needed. However, two specimens were used to evaluate the performance of recycled asphalt pavement materials. One specimen of recycled asphalt pavement materials was ten years old, and another one of recycled asphalt pavement materials was five years old. The results show that the conditions of the environment such as moisture, temperature, and age, decrease the ductility and penetration properties of binder when increase the softening point property of binder. Then the gradation of recycled asphalt pavement aggregate is of the required values to reuse in the mixture, while the flow ratio, the splitting strength ratio, and the dynamic stability ratio, are less than the required value test. With regard to the properties of mixture of recycled asphalt pavement material binder with rejuvenator, the results show that when the penetration and ductility versus percentage of rejuvenator increase, softening point versus percentage of rejuvenator decreases. Also, when the bitumen and rejuvenator percentage increase, the air voids decrease. Consequently, voids filled with asphalt and voids in the mineral aggregate increase. Moreover, the theoretical density and stability values decrease in a mixture containing four-point fifty percent to six percent of bitumen and rejuvenator, whereas the flow values increase. More interestingly, with four percent to four-point fifty percent mixture ratio of bitumen and rejuvenator, density, stability, and flow values increase. The splitting strength ratio values of mixtures and the dynamic stability test (rutting test) values of mixtures with forty percent of specimen one and specimen two respectively are greater than the required value of the standard test. In addition, the high percentage of rejuvenator increases the rut of pavement, in the same manner, the low percentage of rejuvenator induces low rut. In conclusion, the binder content from recycled materials without rejuvenator seems not be sufficient to be reused on the new pavement while the aged recycled material seems to be performed better than no aged recycled material with rejuvenator into bitumen. Then, the rejuvenator can influence the bitumen properties and performance of the pavement. Finally, the pavement made by only recycled pavement materials as a base layer appears to be more economical but cannot be more effective than the pavement made by mixture of new and recycled pavement materials as a base layer.
基金Funded by the Science and Technology Project of Henan Department of Transportation(No.2020J-2-3)Shaanxi Transportation Science and Technology Project(Nos.17-05K,19-10K,19-28K)。
文摘The physical performance of recycled asphalt was used as the main evaluation index to study the optimal range of a self-made rejuvenator.Through the penetration,viscosity and gel permeation chromatography(GPC)tests,the diffusion degree of the rejuvenator under different temperatures and time process was analyzed,and the diffusion efficiency of the rejuvenator was evaluated from the macro and micro perspective.The regeneration mechanism of the rejuvenator in the aged asphalt was also analyzed using the Fourier transform infrared spectroscopy(FTIR),scanning electron microscope(SEM)and chemical composition tests.The research results showed that the optimum rejuvenator content was about 3%.Higher temperature and longer time were beneficial to improving the permeability and diffusion of the rejuvenator.During the aging process,the light components were reduced,and more macromolecular asphaltenes were generated as well as a large number of carbonyl and sulfoxide.After diffusion and regeneration,the light components in the asphalt were supplemented,the wrinkles and gullies of the aged asphalt were almost improved to the surface state of the matrix asphalt.
基金the financial support from the Delft Centre for Materials(DCMat)in the form of project SHM0617,"Unravelling of porous asphalt".
文摘Rejuvenators are products designed to restore original properties to oxidized asphalt binders by restoring the original ratio of asphaltenes to maltenes. But,for a rejuvenator to be successful,it must penetrate the pavement surface. Besides,application of a rejuvenator will also reduce the skid resistance of the pavement. To solve this,these rejuvenators can be encapsulated and mixed in asphalt concrete. Once the stress in the capsules reaches a certain threshold,the particles break and the rejuvenator is released,giving back the original properties of the pavement. The objective of this paper is to show how these capsules behave and define the most appropriate testing methods to find their effect on asphalt concrete. For this,two different types of rejuvenators will be encapsulated and their effect on the properties of the capsules investigated. Besides,the release mechanisms of the capsules will be unravelled.
基金Funded by the Ministry of Science and Technology of China(No.2010DFA82490)Hubei Provincial Science and Technology Department(No.2009CDA053)Hubei Provincial Highway Administration Bureau
文摘Rejuvenator diffusing into aged bitumen was evaluated by determining penetration and chemical components of aged bitumen with rejuvenator coat before and after diffusing experiment. Effects of temperature, time and viscosity of rejuvenator on the diffusing ability of rejuvenator into aged bitumen were investigated. Results indicated that the diffusing ability of rejuvenator into aged bitumen could be enhanced with the increasing of temperature and time, however, the diffusing of rejuvenator into aged bitumen would be restricted due to the volatilization of light component and aging of rejuvenator under high temperature （over 170 ℃）. Rejuvenator with low viscosity diffused into aged bitumen more easily.
基金the financial support provided by National Natural Science Foundation of China(No.51978547)National Key R&D Program of China(No.2018YFB1600200)+2 种基金Technological Innovation Major Project of Hubei Province(2019AEE023)Key R&D Program of Hubei Province(2020BCB064)Hubei Provincial Communication Department Project(2020-2-1-4).
文摘The inherent self-healing ability of asphalt is insufficient and fails to timely repair the cracks due to the combined effect of temperature variation,air oxidation,ultraviolet exposure and traffic loading.Rejuvenator encapsulation based on self-healing asphalt is a green sustainable preventive maintenance technology for asphalt pavement.During the last decade,rejuvenator encapsulation for asphalt self-healing has been a research hotspot and calcium alginate hydrogels encapsulating rejuvenator is a promising self-healing technology.Hence,this review sheds light on the recent advances of calcium alginate hydrogels encapsulating asphalt rejuvenator including selfhealing capsules and fibers.The synthesis methods of calcium alginate capsules and fibers containing rejuvenator were elaborately introduced,and their surface morphology,interior structure,mechanical strength,thermal stability,rejuvenator content,distribution and survival in asphalt materials were systematically analyzed.Besides,the effect of capsules and fiber on the mechanical property and pavement performance of asphalt concrete were explored.Additionally,a comprehensive review about the effect of calcium alginate capsules and fibers on selfhealing ability of asphalt materials were presented,and the rejuvenator release mechanism and release ratio of them in asphalt mixtures were expounded.In a nutshell,this review aims at highlighting the current research achievements on alginate capsules and fibers containing rejuvenator in asphalt materials,and inspiring enhanced self-healing methods for smart and sustainable maintenance of asphalt pavement.
基金The authors sincerely acknowledge the Ministry of Higher Education,Malaysia for the Fundamental Research Grant Scheme with Project Code:FRGS/1/2021/TK01/USM/02/1Appreciation also goes to the deanship of scientific research at King Khalid University for funding this work through large group research project under grant number(RGP2/418/45).
文摘Reclaimed asphalt pavement (RAP) is a byproduct of milling flexible pavements and is typically used in recycling initiatives worldwide. The excessive dosage of RAP can have negative effects on asphalt mixture properties unless it goes through a rejuvenation process. Waste cooking oil (WcO) is one of the green solutions for rejuvenating aged binder in asphaltic concrete, and, like virgin asphalt binder, it contains light oil components. This review article offers current information on WCO's rejuvenating performance and the effect of its variable dosage on binders of varying grades. Several physical and rheological characteristics were investigated, and an appropriate spectrum of reported data was defined for the virgin and rejuvenated binders to ascertain the distinctive characteristics.Additionally, the effect of WCO on binders' asphaltene content, molecular structure,microscopic morphology, mechanical properties, and aging indices was discussed. In the high point of this review, a data range is developed for rejuvenated aged binders based on different properties prior to making a better prediction under different circumstances.Moreover, an optimum value is discussed suggesting the best balance between fatigue performance and rutting resistance. The aged binders modified with WCO exhibit better microchemical properties and particle orientation, with enhanced surface area and coating with aggregates, imitating the micropattern of conventional asphalt binder. Moreover, this review further discusses the economic and ecological aspects of WCO usage as a green asphalt binder rejuvenator.
文摘Asphalt binder plays a significant role in the performance of asphalt pavement.However,due to the limited availability of crude oil and the increasing cost of asphalt,alternatives are being investigated.Reclaimed asphalt pavement(RAP)provides a sustainable solution for the increasing demand of asphalt.However,the amount of RAP which can be utilized in asphalt mixtures is limited due to production and performance issues.Incorporation of high RAP content calls for rejuvenators,which rejuvenate the aged binder and increases the degree of blending.Among various rejuvenators,waste cooking oil(WCO)is gaining increased attention due to its availability and concern towards environmental pollution.When combined in proper proportions with RAP,WCO is a potential rejuvenator,which restores the properties of aged binder to that of unaged asphalt binder.This addresses two problems simultaneously and can greatly benefit the economy and environment.This study focuses on the viscoelastic and rheological properties of the rejuvenated binder with WCO and RAP.The rheological properties are evaluated using frequency sweep test by assessing the complex shear modulus and rutting parameter of different binders.The vis-coelastic properties are studied using multiple stress creep recovery(MSCR)test.The data of the MSCR test are analyzed with the Burger model to understand the viscoelastic prop-erties of the rejuvenated RAP binder.For each of 75%,60%,and 45%RAP,three different oil proportions are selected,and the optimum WCO content is identified.The study concludes that higher RAP content results in lower viscous strain and higher elastic strain,whereas after mixing higher WCO,the viscous strain increases,and the elastic strain decreases.Hence,it is crucial to mix WCO and RAP in the optimum ratio to obtain the desired rheo-logical and viscoelastic properties.
文摘The use of reclaimed asphalt pavement （RAP） in new hot mix asphalt （HMA） by means of hot recycling techniques generates the advantage linked to the exploitation of both lytic and bituminous component, consequently leading to the decrease of both virgin aggregates and bitumen supplying. However, many agencies and public administration authorise RAP percentages ranges from 10% to 30% in hot recycling. The main reason for such a low amount of allowable RAP content is related to the aged bitumen contained in the RAP materials, which is more brittle than a virgin bitumen leading to a final mixture more susceptible to fatigue, thermal and reflection cracking. The use of rejuvenators has the potential to restore rheology and chemical components of aged RAP bitumen, thus allowing a significant increase in the amount of RAP to be properly implemented in HMA. The experimental investigation is described in this paper and carried out through a dynamic shear rheometer （DSR） which provides the rheological characterisation of a paving grade bitumen during its overall service life including its reuse in hot recycling by adopting different rejuvenators. Results show that rejuvenators modify bitumen chemistry and consequently rheology by enhancing the viscous response. Moreover, it was observed that oxidation is less harmful, in terms of stiffness increase, on the 50/50 aged bitumen - virgin bitumen blends （rejuvenated or not） than on the virgin bitumen. Moreover, the addition of a rejuvenator in a bituminous blend containing 50% of bitumen reactivated from RAP could lead to a corresponding composite bituminous phase less subjected to ageing phenomena and even less stiff at the end of service life than the associated virgin bitumen alone.
基金supported by the National Natural Science Foundation of China(51978070)the Shaanxi Natural Science Basic Research Project(2020JM-265)。
文摘Prompting high content of reclaimed asphalt pavement(RAP) to be used in road building and maintenance has drawn great attention. The application of rejuvenators is an efficient way to ensure the performance of recycled asphalt mixtures. However, as various types of rejuvenators emerging, limited understanding about rejuvenation poses challenges to put effective ones into use. For precisely evaluating the performance of rejuvenators, plenty of studies were conducted to ascertain the fundamental mechanism of rejuvenating from the microscopic view. This paper provides an overview of studies focusing on the change inside asphalt after adding rejuvenators. Chemical compositions of rejuvenators were collected as basic information. Both laboratorial experiments and molecular dynamic simulations were investigated to not only compare the effectiveness of several rejuvenators but also explain the rejuvenating mechanism. Finally, functional groups of rejuvenator structures were comprehensively examined to provide global understanding about how chemical compositions influence the efficacy of rejuvenators. This review highlights that the essential capacity of a true rejuvenator is to disturb asphaltene agglomerations. Besides, the molecular structures of rejuvenators will not only affect their deagglomerating abilities but also the performances of diffusion and durability. It has been found that gel-permeation chromatography(GPC) analysis is effective in evaluating the performance of rejuvenators, while Fourier transform infrared spectroscopy(FT-IR) and SARA(saturates, aromatics, resins and asphaltenes) analysis are only suitable for assessing asphalt oxidization. In addition, comparing some tests can only detect changes, molecular dynamic simulation can reveal the mechanism both of data and vision. The results of this work can provide comprehensive knowledge for the evaluation and development of rejuvenators.
基金the Marie Curie IEF research funding, research project Self-healing Asphalt for Road Pavements (SHARP) (project number 622863)
文摘This article presents development of a novel self-healing technology for asphalt pave- ments, where asphalt binder rejuvenator is encapsulated within the compartmented alginate fibres. The key objective of the study was to optimise the compartmented alginate fibre design, i.e., maximising amount of rejuvenator encapsulated within the fibre. The results demonstrate that optimum rejuvenator content in the alginate fibre is of 70：B0 rejuvenator/alginate ratio. The fibres are of sufficient thermal and mechanical strength to survive harsh asphalt mixing and compaction processes. Furthermore, results illustrate that zeer open asfalt beton （ZOAB） asphalt mix containing 5% of 70：30 rejuvenator/alginate ratio compartmented alginate fibres has higher strength, stiffness and better healing properties in comparison to the control asphalt mix, i.e., mix without fibres, and mix containing fibres with lower rejuvenator content. These results show that compartmented alginate fibres encapsulating bitumen rejuvenator present a promising new approach for the development of self-healing asphalt pavement systems.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.52378432 and 52278426)the Key Research and Development Program of Shaanxi Province(Grant No.2022SF-169).
文摘The objective of this paper is to comprehensively review the research progress of bio-oil properties and hot rejuvenation behavior and mechanism to aged asphalt.The preparation process,composition characteristics of bio-oils and their component correspondence with petroleum asphalt were compared.The diffusion and fusion effects of various bio-oils in aged asphalt were introduced.Bio-oil cannot be used as a direct alternative of petroleum asphalt,but it has the potential to effectively rejuvenate aged asphalt binders due to the component similarity with petroleum asphalt and good diffusion properties.For the asphalt rejuvenation,the functionalization treatment methods of bio-oil were discussed such as purification,composition modification and component conversion.The active groups and derivatives in bio-oil can be converted into the missing components of the aged binder through phenolate,grafting,polycondensation,resinifying,but the conversion process and mechanism are still unclear.From the perspectives of diffusion behavior,components regulation,dissolving asphaltene and micro-rejuvenation effect,the rejuvenation behavior and mechanism of bio-oil on aged asphalt were elaborated,and the effects of various types of bio-oil and aged asphalt on rejuvenation behavior were analyzed.The preparation process and dosage of bio-rejuvenator were summarized.The rejuvenation effects of bio-oil on aged asphalt were comprehensively investigated from the aspects of high and low temperature performances,rheological properties,microstructure and chemical composition of bio-rejuvenated asphalt binders.Finally,the limitations of bio-oil used as asphalt rejuvenators were discussed,and future research directions were prospected,which can provide reference and theoretical basis for the development of high-performance bio-oil rejuvenating agents and the engineering application of bio-oil to improve the properties of aged asphalt materials.
文摘Technological advancements have produced sustainable approaches to pavement preservation and reconstruction procedures.Specific recycling processes are being developed to reuse the asphalt concrete guaranteeing costs and environmental effects reduction.Reclaimed asphalt pavement(RAP)is the material worldwide used in the road construction sector to ensure the sustainability of asphalt pavement.RAP employment percentages in asphalt concrete layers are increasing.The development of cold mix asphalt(CMA)recycling technique including high amount of RAP is becoming popular especially for localized patching and potholes.Wearing course layers designed for bicycle lanes realized with 100%RAP and CMA technologies are presented in this research.Two cycle paths rehabilitated with different construction technologies in-plant and in-place recycling techniques are compared by performing a trial field and laboratory analysis on compacted and cored samples.An innovative rejuvenator used as additive specifically designed for CMAs is added as rejuvenator in both RAPs.The main goal is to determine the frictional,physical and mechanical characteristics of solutions produced by using high quantity of recycled materials.British pendulum tester(BPT)and Micro GripTester are applied to assess skid performance and indirect tensile strength test(ITS)and Marshall stability is performed to analyse the mechanical behaviour.RAPs skid resistance and physical-mechanical properties provide positive outcomes with viable characteristics for urban soft-mobility solutions.The innovative machine used in the in-place technique demonstrated excellent performance in terms of milling and mixing,representing a valid alternative for repaving applications in the urban context.
基金The National Natural Science Foundation of China(No.50578031)
文摘The performance evaluation and chemical property analysis of the recycled warm mix asphalt （RWMA） binders containing 100% artificial reclaimed asphalt （ RA） are presented, and the combined effects of different percentages of the rejuvenator and warm mix additive （WMA） additives on RWMA binders are analyzed through laboratory tests. Three types of WMA additives ad one commercial rejuvenator named GST were selected to restore the artificial RA. The laboratory performace tests including the penetration test, softening test ad rotary, viscosity （RV） test were carried out. In addition, the Fourier transform infrared spectroscopy （FTIR） test was performed to explore the chemical property of RWMA binders. The results of the performance tests indicate that the rejuvenator GST has the ability to restore the artificial RA; choosing the optimum content of WMA additives and rejuvenator is the key to restoring 100% artificial RA, since the combined effects of them play an important role in determining the basic laboratory performance of RWMA binders. The FTIR tests show that the process of recycling mainly adjusts the chemical component of aged asphalt and no remarkable change is observed in the FTI1R spectra of RWMA binders in terms of chemical functional groups with the introduction of WMA additives.
基金funding support from the National Natural Science Foundation of China(Nos.51301078,51361017,51461026,51861016,52061021)the European Research Council(Nos.ERC-2013-ADG-340025,ERC-2019-PoC-862485)the Austrian Science Fund(No.I3937-N36).
文摘Recent attention has been directed towards tailoring the internal structure and enhancing the plasticity of metallic glasses(MGs)via rejuvenation treatments.This work aims to comprehensively review the various approaches and underlying mechanisms of inducing rejuvenation in MGs,including thermal-activated methods for deep-cooling cycling treatments and annealing-induced regeneration,mechanical-driven methods of pre-elastic loading and plastic deformation,thermo-mechanically coupled methods for thermo-mechanical creep and thermoplastic forming,and irradiation-induced rejuvenation.Additionally,strategies such as gradient rejuvenation for promoting a favorable distribution of free volume gradients to deflect shear bands are discussed for enhancing plasticity.Finally,the review delves into the challenges and prospects associated with advancing the development of MGs exhibiting high plasticity at ambient conditions.This review is anticipated to contribute to fostering a systematic understanding of the diverse methods and mechanisms employed to enhance the plasticity of MGs via rejuvenation treatments.
文摘Aging,as an inherent stage of life processes,has always been a core research focus in life sciences.Current studies confirm that the accumulation of intracellular molecular damage is a key driver of aging.As protective structures at chromosome ends,telomeres exhibit direct correlations between their length and stability and cellular aging processes,disease risks,and lifespan.This article systematically reviews the structural functions of telomeres and their relationship with aging,with particular emphasis on telomere rejuvenation strategies based on electromagnetic radiation techniques.Key experimental approaches include Gavich's mitotic radiation,Composite Wave Resonator(CWRT),and modern telomere length intervention trials.By synthesizing the latest domestic and international research findings,this paper analyzes the feasibility and limitations of these technologies while exploring their potential applications in anti-aging research,providing theoretical references for future studies.
基金Supported by National Natural Science Foundation of China(Grant No.52275142)Science Center for Gas Turbine Project(Grant Nos.P2022-AIII-003-001,P2022-B-III-005-001)+1 种基金National Science and Technology Major Project(Grant Nos.J2019-IV-0009-0077,Y2022-IV-0002-0019,J2019-IV-0008-0076)National Basic Scientific Research Project(Grant No.JCKY2021601B204)。
文摘Creep is one of the most typical failure modes for the turbine blades of an aero-engine.The microstructure of the turbine blades after long-term service can be adjusted by rejuvenation heat treatment(RHT)to restore its creep properties.In this work,a series of RHT experiments were carried out on a directionally solidified(DS)nickel-based superalloy under different solution temperatures and primary aging temperatures based on the standard heat treatment(SHT)process parameters to investigate the mechanism of temperature influence on DS's microstructure after RHT.It is indicated that a more uniform microstructure can be obtained under higher solution temperatures and lower primary aging temperatures compared to the SHT process.Furthermore,by employing the image processing methods to quantify microstructural parameters,a comprehensive indicator parameter for the RHT effect(marked as Prej)was proposed to characterize the effects of RHT on DS superalloy's microstructure and creep property combined with the entropy weight method.Based on this,a regression model to describe the relationship between RHT process parameters and Prej was constructed by using the response surface methodology(RSM).It is revealed that the optimal solution temperature and primary aging temperature for this DS superalloy are 1283°C and 1095°C,respectively.Then the conclusion was validated through complete creep experiments on the DS superalloy,which showed the creep life after RHT reaches 95.5%of the SHT specimen,and the total life has increased by 20.6%.
