The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song D...The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song Dynasty,writings by Ouyang Xiu's family and epitaphs by his colleagues crafted a balanced narrative emphasizing both his official duties and literary merits,thus constructing a dual image of him as a principled remonstrator and a literary master.In the Southern Song Dynasty,official historiography gradually eroded his complex persona as a political reformer by selectively trimming political disputes and emphasizing his literary lineage,ultimately establishing him as a cultural exemplar beyond factional strife.Throughout this evolution of historical writing,Ouyang Xiu's sharpness as a remonstrator was gradually obscured in historical texts,while his image as a literary master,revered by all,became firmly established.The reshaping of Ouyang Xiu's image in historical writings across the Northern and Southern Song dynasties not only reflects the logic of selecting scholar-official role models under the influence of official ideology but also reveals the inherent pattern whereby individual distinctiveness fades into symbolic construction in historical writing.展开更多
Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical ...Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical research and development.While extensive research has been devoted to constructing molecules that incorporate a trifluoromethylthio(SCF_(3)−)group on a stereogenic carbon,the synthesis of trifluoromethylthiolated alkanes featuring a SCF_(3)-substituted stereogenic carbon at non-activated site remains understudied.Herein,we report a Cu-catalyzed regio-and enantioselective hydroallylation of 1-trifluoromethylthiolated alkenes.Important to the process is the regio-and enantioselective Cu-H insertion to SCF_(3)-substituted alkene to form chiralα-SCF_(3) alkyl copper intermediates,outcompeting unproductive insertion to the coupling partner,and eventually proceed to afford optically active homoallylic trifluoromethylthiolated products.展开更多
Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching t...Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching the construction of an emergency care system based on the concept of“linkage”,delving into its theoretical foundations,exploring innovative construction models,and analyzing practical cases.The study indicates that an emergency care system under the“linkage”concept can effectively integrate resources and enhance efficiency,providing new insights for improving the construction of the emergency care system.It aims to promote the development of the emergency care system towards a more scientific,efficient,and collaborative direction.展开更多
The built environment and construction industry are another significant source of carbon emissions to the environment in the world,through the production of materials,construction activities,and the energy consumed du...The built environment and construction industry are another significant source of carbon emissions to the environment in the world,through the production of materials,construction activities,and the energy consumed during the lifecycle of an asset.These emissions are difficult to manage effectively because the data are not consolidated,the operating conditions are dynamic,and the traditional assessment tools are not able to support continuous and data-driven decisions.The new technologies,especially Digital Twins(DT)and artificial intelligence(AI),have some potential solutions,which will combine the lifecycle data and provide a predictive,adaptive carbon management in the building and urban systems.The given paper is a systematic review of the integration of DT and AI(DT–AI)into carbon management in operational construction and urban planning.Structured database searches and filters on the basis of DT-facilitated carbon monitoring,prediction,optimization,and operational control were used to identify peer-reviewed studies that were published within the last few years and filtered through to gather them.Three main functions of DT–AI systems are outlined in the review:predicting carbon emissions on the basis of data-driven models,optimizing low-carbon design and planning with multi-objective approaches,and providing intelligent control of the energy systems.Some of the major issues are data interoperability,model validation,and a lack of evidence of large-scale deployment.This study combines integrated DT–AI models and their contribution to lifecycle carbon management,unlike the previous reviews of either DT or AI alone.The paper ends with a conclusion and recommendations to create scalable,validated DT–AI solutions to accomplish carbon-neutral built environments.展开更多
Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,...Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,its feasibility has not been fully explored.This study uses data envelopment analysis and the analytic hierarchy process to establish a development potential index,covering technical efficiency,economic cost,application sce-narios,and charging time and range,with an empirical analysis conducted in Beijing.The findings indicated the high feasibility of replacing OCM with electric alternatives,especially within the low-power range.Based on 2023 registered coding dat1,it is projected that by 2030,electrification could reduce regional average con-centrations of CO,NO_(x),PM_(2.5) and VOCs by 12.2%to 56.4%and reduce CO_(2) by 11.7%to 56.9%.Owing to economic considerations,small-and medium-sized machinery are particularly feasible for electrification.Key recommendations include prioritizing the electrification of forklifts,lifting platforms,and small-sized machinery in high-emission areas,particularly in central urban districts.Policies such as carbon taxes,carbon markets,and performance grading systems are suggested to incentivize electrification,along with expanding high-emission restriction zones and improving energy infrastructure to support widespread electrification.展开更多
In response to the Ministry of Education’s requirements for building distinctive model software schools,Software College of Northeastern University and Shenzhen Kingdom Technology Co.,Ltd.jointly developed the specia...In response to the Ministry of Education’s requirements for building distinctive model software schools,Software College of Northeastern University and Shenzhen Kingdom Technology Co.,Ltd.jointly developed the specialized course“Application and Practice of RPA Technology in FinTech”.Addressing pain points in financial digital transformation,the course integrates robotic process automation(RPA)principles,financial domain knowledge,and RPA platform practice into a“technology-scenario-capability”trinity teaching system.Through 64 credit hours of integrated theory and practice,it covers RPA fundamentals,financial applications,RPA operations(including core skills like Web/desktop automation),and AI integration,cultivating students’ability to design and implement automated financial workflows.It innovatively features a RPA simulation platform,30+financial case studies,and modular task resources,creating a“teacher-machine-student”interactive model.Practice demonstrates the course effectively enhances students’integration of technical application and business acumen,providing a scalable paradigm for cultivating interdisciplinary FinTech talent.展开更多
This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants...This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants were two comparable groups of students:one group worked with English input texts(i.e.,E-E),while the other worked with Chinese input texts with the same content(i.e.,C-E).The results showed that over time,the E-E group exhibited a greater tendency to use a wider range of VACs,such as caused-motion constructions,attributives,passives,and phrasal verbs.At the same time,they reduced their use of simpler VACs like intransitive-motion and simple transitive constructions,especially when compared to the C-E group.This pattern was also evident in the topic-based writing during the posttest.These findings strongly support the effectiveness of xu-argument-based continuation tasks in promoting the development of L2 VAC knowledge.They suggest that tasks combining language input with output can significantly enhance learners’ability to use more sophisticated VACs.展开更多
Bio-carbonation of reactive MgO has been regarded as a promising and eco-friendly method for construction and demolition waste(CDW)cementation in various geotechnical engineering applications.However,the beneficial ef...Bio-carbonation of reactive MgO has been regarded as a promising and eco-friendly method for construction and demolition waste(CDW)cementation in various geotechnical engineering applications.However,the beneficial effect of bio-carbonation of reactive MgO cemented CDW(BCM-samples)can be altered when exposed to wetting-drying cycles induced by extreme climate changes or groundwater fluctuations.To better understand the durability of BCM-samples and their underlying deterioration mechanisms,a series of BCM-samples was prepared to investigate their physical-mechanical performance and microstructure evolution subjected to the wetting-drying cycles.The results indicated that the wetting-drying cycles can deteriorate the BCM-samples,and their physical-mechanical behaviors change quickly at the cycle beginning and then smoothly after 2 cycles.With the increase in cycling,the apparent deterioration with efflorescence and microcrack development can be observed.The mass loss and water absorption rates increased while the dry density,compressional wave velocity,and unconfined compression strength decreased.Urea pre-hydrolysis treatment can significantly improve the durability of BCM-samples,as the more hydrated magnesia carbonates(HMCs)enhance the cementing effects.After 10 cycles,the UCS of pre-hydrolyzed samples decreased 25.4%to 4.45 MPa,while that of ordinary samples decreased 50.7%to 1.20 MPa.The deterioration of BCM-samples caused by wetting-drying cycles can be attributed to two factors.One of the main factors is the structural integrity changes caused by the rapid loss of soluble material at the initial cycling stages.Another factor is the decrease in cementation induced by the loss of brucite and HMCs at the following cycle stages.展开更多
The shale gas development in China faces challenges such as complex reservoir conditions and high development costs.Based on the pore pressure and geostress coupling theory,this paper studies the geostress evolution l...The shale gas development in China faces challenges such as complex reservoir conditions and high development costs.Based on the pore pressure and geostress coupling theory,this paper studies the geostress evolution laws and fracture network characteristics of shale gas infill wells.A mechanism model of CN platform logging data and geomechanical parameters is established to simulate the influence of parent well’s production on the geostress in the infill well area.It is suggested that with the increase of production time,normal fault stress state and horizontal stress deflection will occur.The smaller the parent well spacing and the longer the production time,the earlier the normal fault stress state appears and the larger the range.Based on the model,the fracture network morphology and construction parameters of infill wells are optimized.parentparentparentparent The results indicate that:1:A well spacing of 500 m achieves a Pareto optimum between“full reserve coverage”and“stress barrier”;2:A parent well recovery degree of 30%corresponds to the critical point of stress reversal,where the lateral deflection rate of the infill fracture is less than 8%and the SRV loss is minimized;3:6-cluster intensive completion with twice the liquid intensity increases the fracture complexity index by 1.7 times,enhances well group EUR by 15.4%,and reduces single-well cost by 22%.This research fills the theoretical gap in the collaborative optimization of“multi-parameter,multi-objective and multi-constraint”and provide parameter optimization basis for shale gas infill well development in China and help to improve the development efficiency and economic benefits.展开更多
Aiming at the problem of innovative talent training in the industry field in characteristic software colleges,combined with the actual situation of Software College of Northeastern University,this paper analyzes the c...Aiming at the problem of innovative talent training in the industry field in characteristic software colleges,combined with the actual situation of Software College of Northeastern University,this paper analyzes the construction requirements of characteristic talent training mode and training scheme,puts forward the reform of characteristic software innovative talent training scheme integrating production and education,and takes the characteristic direction of financial technology as an example to introduce the curriculum construction based on industry-education integration and school-enterprise cooperation.展开更多
To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite ...To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite element model of the middle tower column during the construction stage was established using ABAQUS to analyze the effects of key parameters,including the angle and pretension of temporary cables,as well as the wall thickness and diameter of temporary diagonal braces.The study examines how these parameters influence the stresses at the towergirder consolidation.The results indicate that the angle of temporary cables significantly affects the tensile stresses at the tower-girder consolidation,while its impact on compressive stresses is minimal.Among all parameters,the pretension of temporary cables has the most pronounced effect on the stresses at the tower-girder consolidation.In contrast,the wall thickness of temporary diagonal braces has only a minor influence,whereas the diameter of temporary diagonal braces has an almost negligible impact.These findings provide valuable insights for optimizing the design and arrangement of temporary support structures in similar bridge construction projects.展开更多
To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction fou...To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction four times successively and the Technical Guidelines for Intelligent Construction(Trial).展开更多
The construction industry is a significant contributor to global CO_(2) emissions,and urgent innovation is needed to mitigate its environmental impact.This paper provides a comprehensive review of scalable approaches ...The construction industry is a significant contributor to global CO_(2) emissions,and urgent innovation is needed to mitigate its environmental impact.This paper provides a comprehensive review of scalable approaches for CO_(2) uptake in construction materials,including the injection of CO_(2) into fresh concrete,the CO_(2) curing of precast concrete,and the use of ceramics as CO_(2) sinks.Among these three approaches,CO_(2) curing methods for concrete represent the most advanced and widely adopted strategies within industrial practice,with substantial research supporting their effectiveness and scalability.The comparison of carbonation mineralisation across three distinct material groups reveals that the direct injection of CO_(2) into fresh concrete mixes results in CO_(2) uptake of less than 3 kg/m3.For the precast concrete elements,the CO_(2) uptake ranges from 30 to 350 kg/m3,while ceramics can achieve uptake efficiencies up to 23 wt.%under pilot-scale conditions.Achieving efficient CO_(2) uptake in fresh and precast concrete without compromising mechanical properties relies on precise control over the CO_(2) dose,a tailored mix design,and optimised curing conditions,while avoiding excessive carbonation that could reduce alkalinity or durability.Valorisation of carbonated materials as supplementary cementitious components or aggregates is identified as an important circular solution,though further research is needed to address regeneration,performance,and standardisation.The review highlights ongoing gaps in life-cycle assessment and industrial-scale validation,and recommends future work on durability and techno-economic optimisation for robust decarbonisation in the cement and concrete industries.展开更多
In this paper,the Jiangxi section of the red army's long march is taken as the research object to construct a red cultural heritage corridor.Introducing the theory of heritage corridor,on the basis of its hierarch...In this paper,the Jiangxi section of the red army's long march is taken as the research object to construct a red cultural heritage corridor.Introducing the theory of heritage corridor,on the basis of its hierarchical decomposition and comparative judgment,a hierarchy model of the red cultural heritage corridor resource is established.The comprehensive scores of each factor are obtained through expert scoring,and the overall pattern of red army corridor is constructed as"ring-shape-point".New ideas for protection and utilization as well as protection implementation measures are proposed,and the spiritual and cultural connotations of long march in Jiangxi are fully explored.This could help the social and economic development of the areas along the long march of red army in Jiangxi,and promote the integrated utilization and coordinated development of resources in the red cultural heritage corridor region.展开更多
To fully leverage the advantages of mechanization and informatization in tunnel boring machine(TBM)operations,the authors aim to promote the advancement of tunnel construction technology toward intelligent development...To fully leverage the advantages of mechanization and informatization in tunnel boring machine(TBM)operations,the authors aim to promote the advancement of tunnel construction technology toward intelligent development.This involved exploring the deep integration of next-generation artificial intelligence technologies,such as sensing technology,automatic control technology,big data technology,deep learning,and machine vision,with key operational processes,including TBM excavation,direction adjustment,step changes,inverted arch block assembly,material transportation,and operation status assurance.The results of this integration are summarized as follows.(1)TBM key excavation parameter prediction algorithm was developed with an accuracy rate exceeding 90%.The TBM intelligent step-change control algorithm,based on machine vision,achieved an image segmentation accuracy rate of 95%and gripper shoe positioning error of±5 mm.(2)An automatic positioning system for inverted arch blocks was developed,enabling real-time perception of the spatial position and deviation during the assembly process.The system maintains an elevation positioning deviation within±3 mm and a horizontal positioning deviation within±10 mm,reducing the number of surveyors in each work team.(3)A TBM intelligent rail transportation system that achieves real-time human-machine positioning,automatic switch opening and closing,automatic obstacle avoidance,intelligent transportation planning,and integrated scheduling and command was designed.Each locomotive formation reduces one shunter and improves comprehensive transportation efficiency by more than 20%.(4)Intelligent analysis and prediction algorithms were developed to monitor and predict the trends of the hydraulic and gear oil parameters in real time,enhancing the proactive maintenance and system reliability.展开更多
Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review cover...Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review covers in-situ testing,intelligent monitoring,and geophysical testing methods,highlighting fundamental principles,testing apparatuses,data processing techniques,and engineering applications.The state-of-the-art summary emphasizes not only cutting-edge innovations for complex and harsh environments but also the transformative role of artificial intelligence and machine learning in data interpretations.The integration of big data and advanced algorithms is particularly impactful,enabling the identification,prediction,and mitigation of potential risks in underground projects.Key aspects of the discussion include detection capabilities,method integration,and data convergence of intelligent technologies to drive enhanced safety,operational efficiency,and predictive reliability.The review also examines future trends in intelligent technologies,emphasizing unified platforms that combine multiple methods,real-time data,and predictive analytics.These advancements are shaping the evolution of underground construction and maintenance,aiming for risk-free,high-efficiency underground engineering.展开更多
To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission leve...To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NO_(x).The exhaust smoke level and excessive emission situation of different machinery types were identified,and their NO_(x)emission levels were monitored according to the free acceleration method.We investigated the correlation of NO_(x)and smoke emission,and proposed suggestions for controlling pollution discharge from construction machinery in the future.The results show that the exhaust smoke level was 0–2.62 m^(−1),followed a log-normal distribution(μ=-1.73,δ=1.09,R^(2)=0.99),with a 5.64%exceedance rate.Differenceswere observed amongmachinery types,with low-power engine forklifts showing higher smoke levels.The NO_(x)emission range was 71–1516 ppm,followed a normal distribution(μ=565.54,δ=309.51,R^(2)=0.83).Differences among machinery types were relatively small.Engine rated net power had the most significant impact on NO_(x)emissions.Thus,NO_(x)emissions from construction machinery need further attention.Furthermore,we found a weak negative correlation(p<0.05)between the emission level of smoke and NO_(x),that is the synergic emission reduction effect is poor,emphasizing the need for NO_(x)emission limits.In the future,the oversight in Beijing should prioritize phasing out ChinaⅠand ChinaⅡmachinery,and monitor emissions from highpower engine ChinaⅢmachinery.展开更多
Zeolite-loaded noble metal catalysts have demonstrated excellent performance in addressing cold-start automotive exhaust NOx emissions and catalytic oxidation of VOCs applications.Pd and Pt are the most commonly used ...Zeolite-loaded noble metal catalysts have demonstrated excellent performance in addressing cold-start automotive exhaust NOx emissions and catalytic oxidation of VOCs applications.Pd and Pt are the most commonly used active metals in PNA and VOC catalysts,respectively.However,despite the same metal/zeolite composition,the efficient active sites for PNA and VOC catalysts have been viewed as mainly Pd^(2+) and Pt^(0),respectively,both of which are different from each other.As a result,various methods need to be applied to dope Pd and Pt in zeolitic support respectively for different usages.No matter which type of metal species is needed,the common requirement for both PNA and VOC catalysts is that the metal species should be highly dispersed in zeolite support and stay stable.The purpose of this paper is to review the progress of synthetic means of zeolite-coated noble metals(Pd,Pt,etc.)as effective PNA or VOC catalysts.To give a better understanding of the relationship between efficient metal species and the introduced methods,the species that contributed to the NOx adsorption(PNA)and VOCs deep catalytic oxidation were first summarized and compared.Then,based on the above discussion,the detailed construction strategies for different active sites in PNA and VOC catalysts,respectively,were elaborated in terms of synthetic routes,precursor selection,and zeolite carrier requirements.It is hoped that this will contribute to a better understanding of noble metal adsorption/catalysis in zeolites and provide promising strategies for the design of adsorption/catalysts with high activity,selectivity and stability.展开更多
Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.T...Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.To contribute to a better understanding of the state of the art of smart techniques for engineering projects,this paper provides a comprehensive review of multi-criteria decision-making(MCDM)techniques,intelligent techniques,and their applications in CEM.First,a comprehensive framework detailing smart technologies for construction projects is developed.Next,the characteristics of CEM are summarized.A bibliometric review is then conducted to investigate the keywords,journals,and clusters related to the application of smart techniques in CEM during 2000-2022.Recent advancements in intelligent techniques are also discussed under the following six topics:①big data technology;②computer vision;③speech recognition;④natural language processing;⑤machine learning;and⑥knowledge representation,understanding,and reasoning.The applications of smart techniques are then illustrated via underground space exploitation.Finally,future research directions for the sustainable development of smart construction are highlighted.展开更多
The advent of parametric design has resulted in a marked increase in the complexity of building.Unfortunately,traditional construction methods make it difficult to meet the needs.Therefore,construction robots have bec...The advent of parametric design has resulted in a marked increase in the complexity of building.Unfortunately,traditional construction methods make it difficult to meet the needs.Therefore,construction robots have become a pivotal production tool in this context.Since the arm span of a single robot usually does not exceed 3 meters,it is not competent for producing large-scale building components.Accordingly,the extension of the robot,s working range is often achieved by external axes.Nevertheless,the coupling control of external axes and robots and their kinematic solution have become key challenges.The primary technical difficulties include customized construction robots,automatic solutions for external axes,fixed axis joints,and specific motion mode control.This paper proposes solutions to these difficulties,introduces the relevant basic concepts and algorithms in detail,and encapsulates these robotics principles and algorithm processes into the Grasshopper plug-in commonly used by architects to form the FURobot software platform.This platform effectively solves the above problems,lowers the threshold for architects,and improves production efficiency.The effectiveness of the algorithm and software in this paper is verified through simulation experiments.展开更多
基金an initial outcome of the Research on the Interactive Relationship Between Biographies and Epitaphs in Ancient China,a project(ID:24BZW023)supported by the National Social Science Fund of China。
文摘The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song Dynasty,writings by Ouyang Xiu's family and epitaphs by his colleagues crafted a balanced narrative emphasizing both his official duties and literary merits,thus constructing a dual image of him as a principled remonstrator and a literary master.In the Southern Song Dynasty,official historiography gradually eroded his complex persona as a political reformer by selectively trimming political disputes and emphasizing his literary lineage,ultimately establishing him as a cultural exemplar beyond factional strife.Throughout this evolution of historical writing,Ouyang Xiu's sharpness as a remonstrator was gradually obscured in historical texts,while his image as a literary master,revered by all,became firmly established.The reshaping of Ouyang Xiu's image in historical writings across the Northern and Southern Song dynasties not only reflects the logic of selecting scholar-official role models under the influence of official ideology but also reveals the inherent pattern whereby individual distinctiveness fades into symbolic construction in historical writing.
基金the National Key R&D Program of China(No.2021YFF0701700)the National Natural Science Foundation of China(Nos.22271264 and 21971228)for financial support.
文摘Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical research and development.While extensive research has been devoted to constructing molecules that incorporate a trifluoromethylthio(SCF_(3)−)group on a stereogenic carbon,the synthesis of trifluoromethylthiolated alkanes featuring a SCF_(3)-substituted stereogenic carbon at non-activated site remains understudied.Herein,we report a Cu-catalyzed regio-and enantioselective hydroallylation of 1-trifluoromethylthiolated alkenes.Important to the process is the regio-and enantioselective Cu-H insertion to SCF_(3)-substituted alkene to form chiralα-SCF_(3) alkyl copper intermediates,outcompeting unproductive insertion to the coupling partner,and eventually proceed to afford optically active homoallylic trifluoromethylthiolated products.
文摘Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching the construction of an emergency care system based on the concept of“linkage”,delving into its theoretical foundations,exploring innovative construction models,and analyzing practical cases.The study indicates that an emergency care system under the“linkage”concept can effectively integrate resources and enhance efficiency,providing new insights for improving the construction of the emergency care system.It aims to promote the development of the emergency care system towards a more scientific,efficient,and collaborative direction.
文摘The built environment and construction industry are another significant source of carbon emissions to the environment in the world,through the production of materials,construction activities,and the energy consumed during the lifecycle of an asset.These emissions are difficult to manage effectively because the data are not consolidated,the operating conditions are dynamic,and the traditional assessment tools are not able to support continuous and data-driven decisions.The new technologies,especially Digital Twins(DT)and artificial intelligence(AI),have some potential solutions,which will combine the lifecycle data and provide a predictive,adaptive carbon management in the building and urban systems.The given paper is a systematic review of the integration of DT and AI(DT–AI)into carbon management in operational construction and urban planning.Structured database searches and filters on the basis of DT-facilitated carbon monitoring,prediction,optimization,and operational control were used to identify peer-reviewed studies that were published within the last few years and filtered through to gather them.Three main functions of DT–AI systems are outlined in the review:predicting carbon emissions on the basis of data-driven models,optimizing low-carbon design and planning with multi-objective approaches,and providing intelligent control of the energy systems.Some of the major issues are data interoperability,model validation,and a lack of evidence of large-scale deployment.This study combines integrated DT–AI models and their contribution to lifecycle carbon management,unlike the previous reviews of either DT or AI alone.The paper ends with a conclusion and recommendations to create scalable,validated DT–AI solutions to accomplish carbon-neutral built environments.
基金supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2024ZD1200200).
文摘Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,its feasibility has not been fully explored.This study uses data envelopment analysis and the analytic hierarchy process to establish a development potential index,covering technical efficiency,economic cost,application sce-narios,and charging time and range,with an empirical analysis conducted in Beijing.The findings indicated the high feasibility of replacing OCM with electric alternatives,especially within the low-power range.Based on 2023 registered coding dat1,it is projected that by 2030,electrification could reduce regional average con-centrations of CO,NO_(x),PM_(2.5) and VOCs by 12.2%to 56.4%and reduce CO_(2) by 11.7%to 56.9%.Owing to economic considerations,small-and medium-sized machinery are particularly feasible for electrification.Key recommendations include prioritizing the electrification of forklifts,lifting platforms,and small-sized machinery in high-emission areas,particularly in central urban districts.Policies such as carbon taxes,carbon markets,and performance grading systems are suggested to incentivize electrification,along with expanding high-emission restriction zones and improving energy infrastructure to support widespread electrification.
文摘In response to the Ministry of Education’s requirements for building distinctive model software schools,Software College of Northeastern University and Shenzhen Kingdom Technology Co.,Ltd.jointly developed the specialized course“Application and Practice of RPA Technology in FinTech”.Addressing pain points in financial digital transformation,the course integrates robotic process automation(RPA)principles,financial domain knowledge,and RPA platform practice into a“technology-scenario-capability”trinity teaching system.Through 64 credit hours of integrated theory and practice,it covers RPA fundamentals,financial applications,RPA operations(including core skills like Web/desktop automation),and AI integration,cultivating students’ability to design and implement automated financial workflows.It innovatively features a RPA simulation platform,30+financial case studies,and modular task resources,creating a“teacher-machine-student”interactive model.Practice demonstrates the course effectively enhances students’integration of technical application and business acumen,providing a scalable paradigm for cultivating interdisciplinary FinTech talent.
文摘This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants were two comparable groups of students:one group worked with English input texts(i.e.,E-E),while the other worked with Chinese input texts with the same content(i.e.,C-E).The results showed that over time,the E-E group exhibited a greater tendency to use a wider range of VACs,such as caused-motion constructions,attributives,passives,and phrasal verbs.At the same time,they reduced their use of simpler VACs like intransitive-motion and simple transitive constructions,especially when compared to the C-E group.This pattern was also evident in the topic-based writing during the posttest.These findings strongly support the effectiveness of xu-argument-based continuation tasks in promoting the development of L2 VAC knowledge.They suggest that tasks combining language input with output can significantly enhance learners’ability to use more sophisticated VACs.
基金supported by the National Natural Science Foundation of China(Grant Nos.42525201 and 42230710).
文摘Bio-carbonation of reactive MgO has been regarded as a promising and eco-friendly method for construction and demolition waste(CDW)cementation in various geotechnical engineering applications.However,the beneficial effect of bio-carbonation of reactive MgO cemented CDW(BCM-samples)can be altered when exposed to wetting-drying cycles induced by extreme climate changes or groundwater fluctuations.To better understand the durability of BCM-samples and their underlying deterioration mechanisms,a series of BCM-samples was prepared to investigate their physical-mechanical performance and microstructure evolution subjected to the wetting-drying cycles.The results indicated that the wetting-drying cycles can deteriorate the BCM-samples,and their physical-mechanical behaviors change quickly at the cycle beginning and then smoothly after 2 cycles.With the increase in cycling,the apparent deterioration with efflorescence and microcrack development can be observed.The mass loss and water absorption rates increased while the dry density,compressional wave velocity,and unconfined compression strength decreased.Urea pre-hydrolysis treatment can significantly improve the durability of BCM-samples,as the more hydrated magnesia carbonates(HMCs)enhance the cementing effects.After 10 cycles,the UCS of pre-hydrolyzed samples decreased 25.4%to 4.45 MPa,while that of ordinary samples decreased 50.7%to 1.20 MPa.The deterioration of BCM-samples caused by wetting-drying cycles can be attributed to two factors.One of the main factors is the structural integrity changes caused by the rapid loss of soluble material at the initial cycling stages.Another factor is the decrease in cementation induced by the loss of brucite and HMCs at the following cycle stages.
文摘The shale gas development in China faces challenges such as complex reservoir conditions and high development costs.Based on the pore pressure and geostress coupling theory,this paper studies the geostress evolution laws and fracture network characteristics of shale gas infill wells.A mechanism model of CN platform logging data and geomechanical parameters is established to simulate the influence of parent well’s production on the geostress in the infill well area.It is suggested that with the increase of production time,normal fault stress state and horizontal stress deflection will occur.The smaller the parent well spacing and the longer the production time,the earlier the normal fault stress state appears and the larger the range.Based on the model,the fracture network morphology and construction parameters of infill wells are optimized.parentparentparentparent The results indicate that:1:A well spacing of 500 m achieves a Pareto optimum between“full reserve coverage”and“stress barrier”;2:A parent well recovery degree of 30%corresponds to the critical point of stress reversal,where the lateral deflection rate of the infill fracture is less than 8%and the SRV loss is minimized;3:6-cluster intensive completion with twice the liquid intensity increases the fracture complexity index by 1.7 times,enhances well group EUR by 15.4%,and reduces single-well cost by 22%.This research fills the theoretical gap in the collaborative optimization of“multi-parameter,multi-objective and multi-constraint”and provide parameter optimization basis for shale gas infill well development in China and help to improve the development efficiency and economic benefits.
文摘Aiming at the problem of innovative talent training in the industry field in characteristic software colleges,combined with the actual situation of Software College of Northeastern University,this paper analyzes the construction requirements of characteristic talent training mode and training scheme,puts forward the reform of characteristic software innovative talent training scheme integrating production and education,and takes the characteristic direction of financial technology as an example to introduce the curriculum construction based on industry-education integration and school-enterprise cooperation.
文摘To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite element model of the middle tower column during the construction stage was established using ABAQUS to analyze the effects of key parameters,including the angle and pretension of temporary cables,as well as the wall thickness and diameter of temporary diagonal braces.The study examines how these parameters influence the stresses at the towergirder consolidation.The results indicate that the angle of temporary cables significantly affects the tensile stresses at the tower-girder consolidation,while its impact on compressive stresses is minimal.Among all parameters,the pretension of temporary cables has the most pronounced effect on the stresses at the tower-girder consolidation.In contrast,the wall thickness of temporary diagonal braces has only a minor influence,whereas the diameter of temporary diagonal braces has an almost negligible impact.These findings provide valuable insights for optimizing the design and arrangement of temporary support structures in similar bridge construction projects.
文摘To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction four times successively and the Technical Guidelines for Intelligent Construction(Trial).
基金funded by the Recovery and Resilience Plan(PRR)to support Collaborative Laboratories(CoLABs),Interface Mission[Notice No.01/C05-i02/2022].
文摘The construction industry is a significant contributor to global CO_(2) emissions,and urgent innovation is needed to mitigate its environmental impact.This paper provides a comprehensive review of scalable approaches for CO_(2) uptake in construction materials,including the injection of CO_(2) into fresh concrete,the CO_(2) curing of precast concrete,and the use of ceramics as CO_(2) sinks.Among these three approaches,CO_(2) curing methods for concrete represent the most advanced and widely adopted strategies within industrial practice,with substantial research supporting their effectiveness and scalability.The comparison of carbonation mineralisation across three distinct material groups reveals that the direct injection of CO_(2) into fresh concrete mixes results in CO_(2) uptake of less than 3 kg/m3.For the precast concrete elements,the CO_(2) uptake ranges from 30 to 350 kg/m3,while ceramics can achieve uptake efficiencies up to 23 wt.%under pilot-scale conditions.Achieving efficient CO_(2) uptake in fresh and precast concrete without compromising mechanical properties relies on precise control over the CO_(2) dose,a tailored mix design,and optimised curing conditions,while avoiding excessive carbonation that could reduce alkalinity or durability.Valorisation of carbonated materials as supplementary cementitious components or aggregates is identified as an important circular solution,though further research is needed to address regeneration,performance,and standardisation.The review highlights ongoing gaps in life-cycle assessment and industrial-scale validation,and recommends future work on durability and techno-economic optimisation for robust decarbonisation in the cement and concrete industries.
基金Supported by the Humanities and Social Science Research Project of Jiangxi Provincial Universities(YS23104).
文摘In this paper,the Jiangxi section of the red army's long march is taken as the research object to construct a red cultural heritage corridor.Introducing the theory of heritage corridor,on the basis of its hierarchical decomposition and comparative judgment,a hierarchy model of the red cultural heritage corridor resource is established.The comprehensive scores of each factor are obtained through expert scoring,and the overall pattern of red army corridor is constructed as"ring-shape-point".New ideas for protection and utilization as well as protection implementation measures are proposed,and the spiritual and cultural connotations of long march in Jiangxi are fully explored.This could help the social and economic development of the areas along the long march of red army in Jiangxi,and promote the integrated utilization and coordinated development of resources in the red cultural heritage corridor region.
文摘To fully leverage the advantages of mechanization and informatization in tunnel boring machine(TBM)operations,the authors aim to promote the advancement of tunnel construction technology toward intelligent development.This involved exploring the deep integration of next-generation artificial intelligence technologies,such as sensing technology,automatic control technology,big data technology,deep learning,and machine vision,with key operational processes,including TBM excavation,direction adjustment,step changes,inverted arch block assembly,material transportation,and operation status assurance.The results of this integration are summarized as follows.(1)TBM key excavation parameter prediction algorithm was developed with an accuracy rate exceeding 90%.The TBM intelligent step-change control algorithm,based on machine vision,achieved an image segmentation accuracy rate of 95%and gripper shoe positioning error of±5 mm.(2)An automatic positioning system for inverted arch blocks was developed,enabling real-time perception of the spatial position and deviation during the assembly process.The system maintains an elevation positioning deviation within±3 mm and a horizontal positioning deviation within±10 mm,reducing the number of surveyors in each work team.(3)A TBM intelligent rail transportation system that achieves real-time human-machine positioning,automatic switch opening and closing,automatic obstacle avoidance,intelligent transportation planning,and integrated scheduling and command was designed.Each locomotive formation reduces one shunter and improves comprehensive transportation efficiency by more than 20%.(4)Intelligent analysis and prediction algorithms were developed to monitor and predict the trends of the hydraulic and gear oil parameters in real time,enhancing the proactive maintenance and system reliability.
基金supported by Ministry of Education of Singapore,under Academic Research Fund Tier 1(Grant Number RG143/23).
文摘Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review covers in-situ testing,intelligent monitoring,and geophysical testing methods,highlighting fundamental principles,testing apparatuses,data processing techniques,and engineering applications.The state-of-the-art summary emphasizes not only cutting-edge innovations for complex and harsh environments but also the transformative role of artificial intelligence and machine learning in data interpretations.The integration of big data and advanced algorithms is particularly impactful,enabling the identification,prediction,and mitigation of potential risks in underground projects.Key aspects of the discussion include detection capabilities,method integration,and data convergence of intelligent technologies to drive enhanced safety,operational efficiency,and predictive reliability.The review also examines future trends in intelligent technologies,emphasizing unified platforms that combine multiple methods,real-time data,and predictive analytics.These advancements are shaping the evolution of underground construction and maintenance,aiming for risk-free,high-efficiency underground engineering.
基金supported by the Energy Foundation(No.G-2203-33693).
文摘To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NO_(x).The exhaust smoke level and excessive emission situation of different machinery types were identified,and their NO_(x)emission levels were monitored according to the free acceleration method.We investigated the correlation of NO_(x)and smoke emission,and proposed suggestions for controlling pollution discharge from construction machinery in the future.The results show that the exhaust smoke level was 0–2.62 m^(−1),followed a log-normal distribution(μ=-1.73,δ=1.09,R^(2)=0.99),with a 5.64%exceedance rate.Differenceswere observed amongmachinery types,with low-power engine forklifts showing higher smoke levels.The NO_(x)emission range was 71–1516 ppm,followed a normal distribution(μ=565.54,δ=309.51,R^(2)=0.83).Differences among machinery types were relatively small.Engine rated net power had the most significant impact on NO_(x)emissions.Thus,NO_(x)emissions from construction machinery need further attention.Furthermore,we found a weak negative correlation(p<0.05)between the emission level of smoke and NO_(x),that is the synergic emission reduction effect is poor,emphasizing the need for NO_(x)emission limits.In the future,the oversight in Beijing should prioritize phasing out ChinaⅠand ChinaⅡmachinery,and monitor emissions from highpower engine ChinaⅢmachinery.
基金supported by Zhongtian Iron and Steel-University of Science and Technology Beijing Youth Science and Technology Innovation Fund(No.FZTNTC2024050005)National Engineering Laboratory for Mobile Source Emission Control Technology,China(No.NELMS2020A07)The Fundamental Research Funds for the Central Universities,China(No.FRF-AT-20-12)。
文摘Zeolite-loaded noble metal catalysts have demonstrated excellent performance in addressing cold-start automotive exhaust NOx emissions and catalytic oxidation of VOCs applications.Pd and Pt are the most commonly used active metals in PNA and VOC catalysts,respectively.However,despite the same metal/zeolite composition,the efficient active sites for PNA and VOC catalysts have been viewed as mainly Pd^(2+) and Pt^(0),respectively,both of which are different from each other.As a result,various methods need to be applied to dope Pd and Pt in zeolitic support respectively for different usages.No matter which type of metal species is needed,the common requirement for both PNA and VOC catalysts is that the metal species should be highly dispersed in zeolite support and stay stable.The purpose of this paper is to review the progress of synthetic means of zeolite-coated noble metals(Pd,Pt,etc.)as effective PNA or VOC catalysts.To give a better understanding of the relationship between efficient metal species and the introduced methods,the species that contributed to the NOx adsorption(PNA)and VOCs deep catalytic oxidation were first summarized and compared.Then,based on the above discussion,the detailed construction strategies for different active sites in PNA and VOC catalysts,respectively,were elaborated in terms of synthetic routes,precursor selection,and zeolite carrier requirements.It is hoped that this will contribute to a better understanding of noble metal adsorption/catalysis in zeolites and provide promising strategies for the design of adsorption/catalysts with high activity,selectivity and stability.
基金funded by the project of Guangdong Provincial Basic and Applied Basic Research Fund Committee(2022A1515240073)the Pearl River Talent Recruitment Program(2019CX01G338),Guangdong Province.
文摘Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.To contribute to a better understanding of the state of the art of smart techniques for engineering projects,this paper provides a comprehensive review of multi-criteria decision-making(MCDM)techniques,intelligent techniques,and their applications in CEM.First,a comprehensive framework detailing smart technologies for construction projects is developed.Next,the characteristics of CEM are summarized.A bibliometric review is then conducted to investigate the keywords,journals,and clusters related to the application of smart techniques in CEM during 2000-2022.Recent advancements in intelligent techniques are also discussed under the following six topics:①big data technology;②computer vision;③speech recognition;④natural language processing;⑤machine learning;and⑥knowledge representation,understanding,and reasoning.The applications of smart techniques are then illustrated via underground space exploitation.Finally,future research directions for the sustainable development of smart construction are highlighted.
基金National Key R&D Program of China(Nos.2023YFC3806900,2022YFE0141400)。
文摘The advent of parametric design has resulted in a marked increase in the complexity of building.Unfortunately,traditional construction methods make it difficult to meet the needs.Therefore,construction robots have become a pivotal production tool in this context.Since the arm span of a single robot usually does not exceed 3 meters,it is not competent for producing large-scale building components.Accordingly,the extension of the robot,s working range is often achieved by external axes.Nevertheless,the coupling control of external axes and robots and their kinematic solution have become key challenges.The primary technical difficulties include customized construction robots,automatic solutions for external axes,fixed axis joints,and specific motion mode control.This paper proposes solutions to these difficulties,introduces the relevant basic concepts and algorithms in detail,and encapsulates these robotics principles and algorithm processes into the Grasshopper plug-in commonly used by architects to form the FURobot software platform.This platform effectively solves the above problems,lowers the threshold for architects,and improves production efficiency.The effectiveness of the algorithm and software in this paper is verified through simulation experiments.