The increasing occurrence of corrosion-related damage in steel pipelines has led to the growing use of composite-based repair techniques as an efficient alternative to traditional replacement methods.Computer modeling...The increasing occurrence of corrosion-related damage in steel pipelines has led to the growing use of composite-based repair techniques as an efficient alternative to traditional replacement methods.Computer modeling and structural analysis were performed for the repair reinforcement of a steel pipeline with a composite bandage.A preliminary analysis of possible contact interaction schemes was implemented based on the theory of cylindrical shells,taking into account transverse shear deformations.The finite element method was used for a detailed study of the stress state of the composite bandage and the reinforced section of the pipeline.The limit state of the reinforced section was assessed based on the von Mises criterion for steel and the Tsai-Wu criterion for composites.The effectiveness of the repair was demonstrated on a pipeline whose wall thickness had decreased by 20%as a result of corrosion damage.At a nominal pressure of P=6 MPa,the maximum normal stress in the weakened area reached 381 MPa.The installation of a composite bandage reduced this stress to 312 MPa,making the repaired section virtually as strong as the undamaged pipeline.Due to the linearity of the problem,the results obtained can be easily used to find critical internal pressure values.展开更多
Excitonics,an alternative to romising for processing information since semiconductor electronics is rapidly approaching the end of Moore’s law.Currently,the development of excitonic devices,where exciton flow is cont...Excitonics,an alternative to romising for processing information since semiconductor electronics is rapidly approaching the end of Moore’s law.Currently,the development of excitonic devices,where exciton flow is controlled,is mainly focused on electric-field modulation or exciton polaritons in high-Q cavities.Here,we show an alloptical strategy to manipulate the exciton flow in a binary colloidal quantum well complex through mediation of the Förster resonance energy transfer(FRET)by stimulated emission.In the spontaneous emission regime,FRET naturally occurs between a donor and an acceptor.In contrast,upon stronger excitation,the ultrafast consumption of excitons by stimulated emission effectively engineers the excitonic flow from the donors to the acceptors.Specifically,the acceptors’stimulated emission significantly accelerates the exciton flow,while the donors’stimulated emission almost stops this process.On this basis,a FRET-coupled rate equation model is derived to understand the controllable exciton flow using the density of the excited donors and the unexcited acceptors.The results will provide an effective alloptical route for realizing excitonic devices under room temperature operation.展开更多
This review details the advancement in the development of V–Ti-based hydrogen storage materials for using in metal hydride(MH)tanks to supply hydrogen to fuel cells at relatively ambient temperatures and pressures.V...This review details the advancement in the development of V–Ti-based hydrogen storage materials for using in metal hydride(MH)tanks to supply hydrogen to fuel cells at relatively ambient temperatures and pressures.V–Tibased solid solution alloys are excellent hydrogen storage materials among many metal hydrides due to their high reversible hydrogen storage capacity which is over 2 wt%at ambient temperature.The preparation methods,structure characteristics,improvement methods of hydrogen storage performance,and attenuation mechanism are systematically summarized and discussed.The relationships between hydrogen storage properties and alloy compositions as well as phase structures are discussed emphatically.For large-scale applications on MH tanks,it is necessary to develop low-cost and high-performance V–Ti-based solid solution alloys with high reversible hydrogen storage capacity,good cyclic durability,and excellent activation performance.展开更多
Bioprinting is a revolutionary technology within the field of tissue engineering that enables the precise fabrication of three-dimensional(3D)tissue constructs.It combines the principles of engineering and biology to ...Bioprinting is a revolutionary technology within the field of tissue engineering that enables the precise fabrication of three-dimensional(3D)tissue constructs.It combines the principles of engineering and biology to create structures that closely mimic the complexity of native human tissues,facilitating advancements in regenerative medicine and personalized healthcare.This review paper systematically explores the challenges and design requirements in the fabrication of 3D biomimetic tissue constructs,emphasizing the need for advanced bioprinting strategies.Achieving biomimicry involves creating 3D anatomically relevant structures,biomimetic microenvironments,and vascularization.The focus is on overcoming existing bottlenecks through advancements in both fabrication techniques and bio-inks.Future directions in bioprinting are outlined,including multi-modal bioprinting systems,in-situ bioprinting,and the integration of machine learning into bioprinting processes.The critical role of bio-inks and printing methodologies in influencing cell viability is highlighted,providing insights into strategies for enhancing cellular functionality throughout the bioprinting process.Furthermore,the paper addresses post-fabrication considerations,particularly in accelerating tissue maturation,as a pivotal component for advancing the clinical applicability of bioprinted tissues.By navigating through the challenges,innovations,and prospects of advanced bioprinting strategies,this review highlights the transformative impact on tissue engineering.Pushing the boundaries of technological capabilities,these strategies hold the promise of groundbreaking advancements in regenerative medicine and personalized healthcare.Ultimately,the integration of these advanced techniques into bioprinting processes will pave the way for the development of more highly biomimetic and functional bioprinted tissues.展开更多
The feasibility of using a problem-dependent method to solve systems of second order ODEs is corroborated by an eigen-based theory and a methodology to develop such a numerical method is constructed.The key steps of t...The feasibility of using a problem-dependent method to solve systems of second order ODEs is corroborated by an eigen-based theory and a methodology to develop such a numerical method is constructed.The key steps of this methodology are to decouple a system of ODEs of second order into a set of uncoupled ODEs of second order;next,an eigen-dependent method is proposed to approximate the solution of each uncoupled ODE of second order.It is vital to transform all eigen-dependent methods to a problem-dependent method to bypass an Eigen analysis.The development of an eigen-dependent method plays a key role in this methodology so that slow eigenmodes can be accurately integrated while there is no instability or excessive amplitude growth in fast eigenmodes.This can explain why a problem-dependent method can simultaneously combine the explicitness of each step and A-stability.Consequently,huge computational efforts can be saved for solving nonlinear stiff problems.A new family of problem-dependent methods is developed in this work so that the feasibility of the proposed methodology can be affirmed.It has almost the same performance as that of the HHT-αmethod.However,it can save more than 99.5%of CPU demand in approximating a solution for a system of 1000 nonlinear second order ODEs.展开更多
Self-assembled monolayers(SAMs)are widely used as hole transport materials in inverted perovskite solar cells,offering low parasitic absorption and suitability for semitransparent and tandem solar cells.While SAMs hav...Self-assembled monolayers(SAMs)are widely used as hole transport materials in inverted perovskite solar cells,offering low parasitic absorption and suitability for semitransparent and tandem solar cells.While SAMs have shown to be promising in small-area devices(≤1 cm^(2)),their application in larger areas has been limited by a lack of knowledge regarding alternative deposition methods beyond the common spin-coating approach.Here,we compare spin-coating and upscalable methods such as thermal evaporation and spray-coating for[2-(9H-carbazol-9-yl)ethyl]phosphonic acid(2PACz),one of the most common carbazole-based SAMs.The impact of these deposition methods on the device performance is investigated,revealing that the spray-coating technique yields higher device performance.Furthermore,our work provides guidelines for the deposition of SAM materials for the fabrication of perovskite solar modules.In addition,we provide an extensive characterization of 2PACz films focusing on thermal evaporation and spray-coating methods,which allow for thicker 2PACz deposition.It is found that the optimal 2PACz deposition conditions corresponding to the highest device performances do not always correlate with the monolayer characteristics.展开更多
The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geo...The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geomorphic signs of recent activity,and has been scientifically confirmed as active through geological and geophysical studies.In this work,we describe an Integrated along the Lembang Fault,which can be used for geodynamic research in Indonesia.We discuss the design of a seismic and Global Navigation Satellite System(GNSS)array sensor network for continuous monitoring,and report the status of monitoring stations that periodically collect highly accurate,continuous seismographic and GNSS readings,transmitting these data to a central server in Bandung for post-processing.Solutions from the array data are used to provide precise measurements of the deformation of the Earth’s surface over large distances,allowing for spatio-temporal tracking of tectonic movement,and resulting in a better understanding of seismic events in the region.In this study,our investigation revealed a significant compression rate of an estimated 13 microstrain/yr along the Lembang Fault,whereas the strain rate is much smaller farther south of the fault.This study presents the design of a seismo-geodetic observatory network that can be implemented in earthquake-prone regions for mitigation purposes,with particular utility for studying other active faults that also traverse populated areas in Indonesia.展开更多
The high hydrogen desorption density(19.6 wt%)of ammonia borane(AB)makes it one of the most promising chemical hydrogen storage materials.Developing cost-effective catalysts is the key for accelerating the hydrolysis ...The high hydrogen desorption density(19.6 wt%)of ammonia borane(AB)makes it one of the most promising chemical hydrogen storage materials.Developing cost-effective catalysts is the key for accelerating the hydrolysis of AB.Herein,we present a straightforward synthesis method for the Cu_(2)O decorated CoO catalyst derived from ZIF-67 precursors using carbothermal shock(~1 s)in air.The obtained results demonstrate that a small amount of Cu_(2)O doping into CoO synergistically enhances AB hydrolysis,resulting in an almost fivefold increase in turnover frequency(TOF=97 molH_(2)molCoO-1min-1at 298 K).Further studies indicated that the incorporation of Cu_(2)O alters the electronic distribution of the surface of catalysts,introducing more oxygen vacancies and increasing the pyridinic nitrogen content.The increased oxygen vacancies effectively enhanced the adsorption and activation ability of active sites for reactants(H_(2)O and AB),while the targeting effect of pyridinic nitrogen enhances the dispersion of the catalyst.Theoretical analysis reveals that CoO plays a key role in the dissociation of H_(2)O,while minor doping with Cu_(2)O substantially reduces the dissociation energy barrier of AB.This research provides a novel strategy for the design and efficient preparation of AB hydrolysis catalysts for efficient hydrogen production.展开更多
In this study,the advanced machine learning algorithm NESTORE(Next Strong Related Earthquake)was applied to the Japan Meteorological Agency catalog(1973-2024).It calculates the probability that the aftershocks will re...In this study,the advanced machine learning algorithm NESTORE(Next Strong Related Earthquake)was applied to the Japan Meteorological Agency catalog(1973-2024).It calculates the probability that the aftershocks will reach or exceed a magnitude equal to the magnitude of the mainshock minus one and classifies the clusters as type A or type B,depending on whether this condition is met or not.It has been shown useful in the tests in Italy,western Slovenia,Greece,and California.Due to Japan’s high and complex seismic activity,new algorithms were developed to complement NESTORE:a hybrid cluster identification method,which uses both ETAS-based stochastic declustering and deterministic graph-based selection,and REPENESE(RElevant features,class imbalance PErcentage,NEighbour detection,SElection),an algorithm for detecting outliers in skewed class distributions,which takes in account if one class has a larger number of samples with respect to the other(class imbalance).Trained with data from 1973 to 2004(7 type A and 43 type B clusters)and tested from 2005 to 2023(4 type A and 27 type B clusters),the method correctly forecasted 75%of A clusters and 96%of B clusters,achieving a precision of 0.75 and an accuracy of 0.94 six hours after the mainshock.It accurately classified the 2011 Tōhoku event cluster.Near-real-time forecasting was applied to the sequence after the April 17,2024 M6.6 earthquake in Shikoku,correctly classifying it as a“Type B cluster”.These results highlight the potential for the forecasting of strong aftershocks in regions with high seismicity and class imbalance,as evidenced by the high recall,precision and accuracy values achieved in the test phase.展开更多
文摘The increasing occurrence of corrosion-related damage in steel pipelines has led to the growing use of composite-based repair techniques as an efficient alternative to traditional replacement methods.Computer modeling and structural analysis were performed for the repair reinforcement of a steel pipeline with a composite bandage.A preliminary analysis of possible contact interaction schemes was implemented based on the theory of cylindrical shells,taking into account transverse shear deformations.The finite element method was used for a detailed study of the stress state of the composite bandage and the reinforced section of the pipeline.The limit state of the reinforced section was assessed based on the von Mises criterion for steel and the Tsai-Wu criterion for composites.The effectiveness of the repair was demonstrated on a pipeline whose wall thickness had decreased by 20%as a result of corrosion damage.At a nominal pressure of P=6 MPa,the maximum normal stress in the weakened area reached 381 MPa.The installation of a composite bandage reduced this stress to 312 MPa,making the repaired section virtually as strong as the undamaged pipeline.Due to the linearity of the problem,the results obtained can be easily used to find critical internal pressure values.
基金financial support through the AcRF Tier1 grant(MOE2019-T1-002-087)the Singapore National Research Foundation for financial support under the Program of NRF-NRFI-2016-08financial support from the TUBA.
文摘Excitonics,an alternative to romising for processing information since semiconductor electronics is rapidly approaching the end of Moore’s law.Currently,the development of excitonic devices,where exciton flow is controlled,is mainly focused on electric-field modulation or exciton polaritons in high-Q cavities.Here,we show an alloptical strategy to manipulate the exciton flow in a binary colloidal quantum well complex through mediation of the Förster resonance energy transfer(FRET)by stimulated emission.In the spontaneous emission regime,FRET naturally occurs between a donor and an acceptor.In contrast,upon stronger excitation,the ultrafast consumption of excitons by stimulated emission effectively engineers the excitonic flow from the donors to the acceptors.Specifically,the acceptors’stimulated emission significantly accelerates the exciton flow,while the donors’stimulated emission almost stops this process.On this basis,a FRET-coupled rate equation model is derived to understand the controllable exciton flow using the density of the excited donors and the unexcited acceptors.The results will provide an effective alloptical route for realizing excitonic devices under room temperature operation.
基金supported by the Key-Area Research and Development Program of Guangdong Province(No.2023B0909060001)the National Natural Science Foundation of China(No.52271213)。
文摘This review details the advancement in the development of V–Ti-based hydrogen storage materials for using in metal hydride(MH)tanks to supply hydrogen to fuel cells at relatively ambient temperatures and pressures.V–Tibased solid solution alloys are excellent hydrogen storage materials among many metal hydrides due to their high reversible hydrogen storage capacity which is over 2 wt%at ambient temperature.The preparation methods,structure characteristics,improvement methods of hydrogen storage performance,and attenuation mechanism are systematically summarized and discussed.The relationships between hydrogen storage properties and alloy compositions as well as phase structures are discussed emphatically.For large-scale applications on MH tanks,it is necessary to develop low-cost and high-performance V–Ti-based solid solution alloys with high reversible hydrogen storage capacity,good cyclic durability,and excellent activation performance.
基金support from NTU Presidential Postdoctoral Fellowshipthe support from the National Research Foundation,Singapore,under its NRF Investigatorship(NRFNRFI07-2021-007,Funding Awardee:Wai Yee Yeong)。
文摘Bioprinting is a revolutionary technology within the field of tissue engineering that enables the precise fabrication of three-dimensional(3D)tissue constructs.It combines the principles of engineering and biology to create structures that closely mimic the complexity of native human tissues,facilitating advancements in regenerative medicine and personalized healthcare.This review paper systematically explores the challenges and design requirements in the fabrication of 3D biomimetic tissue constructs,emphasizing the need for advanced bioprinting strategies.Achieving biomimicry involves creating 3D anatomically relevant structures,biomimetic microenvironments,and vascularization.The focus is on overcoming existing bottlenecks through advancements in both fabrication techniques and bio-inks.Future directions in bioprinting are outlined,including multi-modal bioprinting systems,in-situ bioprinting,and the integration of machine learning into bioprinting processes.The critical role of bio-inks and printing methodologies in influencing cell viability is highlighted,providing insights into strategies for enhancing cellular functionality throughout the bioprinting process.Furthermore,the paper addresses post-fabrication considerations,particularly in accelerating tissue maturation,as a pivotal component for advancing the clinical applicability of bioprinted tissues.By navigating through the challenges,innovations,and prospects of advanced bioprinting strategies,this review highlights the transformative impact on tissue engineering.Pushing the boundaries of technological capabilities,these strategies hold the promise of groundbreaking advancements in regenerative medicine and personalized healthcare.Ultimately,the integration of these advanced techniques into bioprinting processes will pave the way for the development of more highly biomimetic and functional bioprinted tissues.
文摘The feasibility of using a problem-dependent method to solve systems of second order ODEs is corroborated by an eigen-based theory and a methodology to develop such a numerical method is constructed.The key steps of this methodology are to decouple a system of ODEs of second order into a set of uncoupled ODEs of second order;next,an eigen-dependent method is proposed to approximate the solution of each uncoupled ODE of second order.It is vital to transform all eigen-dependent methods to a problem-dependent method to bypass an Eigen analysis.The development of an eigen-dependent method plays a key role in this methodology so that slow eigenmodes can be accurately integrated while there is no instability or excessive amplitude growth in fast eigenmodes.This can explain why a problem-dependent method can simultaneously combine the explicitness of each step and A-stability.Consequently,huge computational efforts can be saved for solving nonlinear stiff problems.A new family of problem-dependent methods is developed in this work so that the feasibility of the proposed methodology can be affirmed.It has almost the same performance as that of the HHT-αmethod.However,it can save more than 99.5%of CPU demand in approximating a solution for a system of 1000 nonlinear second order ODEs.
基金supported by funding from the Energy Materials and Surface Sciences Unit of the Okinawa Institute of Science and Technology Graduate University,the OIST R&D Cluster Research Program,the OIST Proof of Concept(POC)Program,the JSPS KAKENHI Grant Number JP21F21754 and Alexander von Humboldt Foundation。
文摘Self-assembled monolayers(SAMs)are widely used as hole transport materials in inverted perovskite solar cells,offering low parasitic absorption and suitability for semitransparent and tandem solar cells.While SAMs have shown to be promising in small-area devices(≤1 cm^(2)),their application in larger areas has been limited by a lack of knowledge regarding alternative deposition methods beyond the common spin-coating approach.Here,we compare spin-coating and upscalable methods such as thermal evaporation and spray-coating for[2-(9H-carbazol-9-yl)ethyl]phosphonic acid(2PACz),one of the most common carbazole-based SAMs.The impact of these deposition methods on the device performance is investigated,revealing that the spray-coating technique yields higher device performance.Furthermore,our work provides guidelines for the deposition of SAM materials for the fabrication of perovskite solar modules.In addition,we provide an extensive characterization of 2PACz films focusing on thermal evaporation and spray-coating methods,which allow for thicker 2PACz deposition.It is found that the optimal 2PACz deposition conditions corresponding to the highest device performances do not always correlate with the monolayer characteristics.
基金the National Research and InnovationAgency of Indonesia (BRIN) under research grant Rumah Program Kebencanaan 2022-2025support from the Earth Observatory Singapore (EOS)supported by the Ministry of Higher Education, Science,and Technology, and Institut Teknologi Bandung through the Indonesian Collaborative Research Program.
文摘The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geomorphic signs of recent activity,and has been scientifically confirmed as active through geological and geophysical studies.In this work,we describe an Integrated along the Lembang Fault,which can be used for geodynamic research in Indonesia.We discuss the design of a seismic and Global Navigation Satellite System(GNSS)array sensor network for continuous monitoring,and report the status of monitoring stations that periodically collect highly accurate,continuous seismographic and GNSS readings,transmitting these data to a central server in Bandung for post-processing.Solutions from the array data are used to provide precise measurements of the deformation of the Earth’s surface over large distances,allowing for spatio-temporal tracking of tectonic movement,and resulting in a better understanding of seismic events in the region.In this study,our investigation revealed a significant compression rate of an estimated 13 microstrain/yr along the Lembang Fault,whereas the strain rate is much smaller farther south of the fault.This study presents the design of a seismo-geodetic observatory network that can be implemented in earthquake-prone regions for mitigation purposes,with particular utility for studying other active faults that also traverse populated areas in Indonesia.
基金financially supported by the National Natural Science Foundation of China(No.52301276)Zhejiang Provincial Natural Science Foundation of China(No.24E010001)+2 种基金Lishui Science and Technology Plan Project(No.2023GYX09)the support of the National Natural Science Foundation of China(52371229)Shanghai High-level Talent start funding
文摘The high hydrogen desorption density(19.6 wt%)of ammonia borane(AB)makes it one of the most promising chemical hydrogen storage materials.Developing cost-effective catalysts is the key for accelerating the hydrolysis of AB.Herein,we present a straightforward synthesis method for the Cu_(2)O decorated CoO catalyst derived from ZIF-67 precursors using carbothermal shock(~1 s)in air.The obtained results demonstrate that a small amount of Cu_(2)O doping into CoO synergistically enhances AB hydrolysis,resulting in an almost fivefold increase in turnover frequency(TOF=97 molH_(2)molCoO-1min-1at 298 K).Further studies indicated that the incorporation of Cu_(2)O alters the electronic distribution of the surface of catalysts,introducing more oxygen vacancies and increasing the pyridinic nitrogen content.The increased oxygen vacancies effectively enhanced the adsorption and activation ability of active sites for reactants(H_(2)O and AB),while the targeting effect of pyridinic nitrogen enhances the dispersion of the catalyst.Theoretical analysis reveals that CoO plays a key role in the dissociation of H_(2)O,while minor doping with Cu_(2)O substantially reduces the dissociation energy barrier of AB.This research provides a novel strategy for the design and efficient preparation of AB hydrolysis catalysts for efficient hydrogen production.
基金funded by a grant from the Italian Ministry of Foreign Affairs and International Cooperation and Co-funded within the RETURN Extended Partnership and received funding from the European Union Next-GenerationEU(National Recovery and Resilience Plan-NRRP,Mission 4,Component 2,Investment 1.3-D.D.12432/8/2022,PE0000005)the grant“Progetto INGV Pianeta Dinamico:Near real-time results of Physical and Statistical Seismology for earthquakes observations,modelling and forecasting(NEMESIS)”-code CUP D53J19000170001-funded by Italian Ministry MIUR(“Fondo Finalizzato al rilancio degli investimenti delle amministrazioni centrali dello Stato e allo sviluppo del Paese”,legge 145/2018)supported by the Japan Ministry of Education,Culture,Sports,Science and Technology(MEXT)project for seismology Toward Research innovation with data of earthquakes(STAR-E),Grant Number JPJ010217.
文摘In this study,the advanced machine learning algorithm NESTORE(Next Strong Related Earthquake)was applied to the Japan Meteorological Agency catalog(1973-2024).It calculates the probability that the aftershocks will reach or exceed a magnitude equal to the magnitude of the mainshock minus one and classifies the clusters as type A or type B,depending on whether this condition is met or not.It has been shown useful in the tests in Italy,western Slovenia,Greece,and California.Due to Japan’s high and complex seismic activity,new algorithms were developed to complement NESTORE:a hybrid cluster identification method,which uses both ETAS-based stochastic declustering and deterministic graph-based selection,and REPENESE(RElevant features,class imbalance PErcentage,NEighbour detection,SElection),an algorithm for detecting outliers in skewed class distributions,which takes in account if one class has a larger number of samples with respect to the other(class imbalance).Trained with data from 1973 to 2004(7 type A and 43 type B clusters)and tested from 2005 to 2023(4 type A and 27 type B clusters),the method correctly forecasted 75%of A clusters and 96%of B clusters,achieving a precision of 0.75 and an accuracy of 0.94 six hours after the mainshock.It accurately classified the 2011 Tōhoku event cluster.Near-real-time forecasting was applied to the sequence after the April 17,2024 M6.6 earthquake in Shikoku,correctly classifying it as a“Type B cluster”.These results highlight the potential for the forecasting of strong aftershocks in regions with high seismicity and class imbalance,as evidenced by the high recall,precision and accuracy values achieved in the test phase.
