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Journal of environmental Sciences 2020年第4期32卷 364-374页

作者： Peidong Su Junke Zhang Yadong Li department of civil&environmental engineering Jackson State UniversityJacksonMS39217USA

The leaching concentrations of different metals in stainless steel pickling residue(SSPR)were determined and the toxic metals were treated using Na2 S·xH2 O,FeSO4·6 H2 O,and phosphoric acid.A modified European Community Bureau of Reference(BCR)sequential extraction was used to identify the speciation of the concerned *** showed that SSPR contains a large amount of Ca(58.41%),Fe(29.44%),Cr(3.83%),Ni(2.94%),Mn(2.82%)and some of Al,Cu,Mg,*** them,Cr and Ni were the most toxic metals in SSPR,thus the raw SSPR falls into hazardous waste category due to the leaching amount of *** addition,the leached Cr was identified as Cr6+(MgCr04)in the *** test revealed that risk assessment code(RAC)of Cr and Ni were 33.29%and 61.7%,indicating they posed"high"and"very high"risk to the environment,*** fixing by Na2 S·xH2 O and FeSO4·6 H2 O,the leaching concentrations of Cr and Ni were less than 1.5 and 0.5 mg/L,*** fixing by Na2 S·xH2 O and FeSO4·6 H2 O the tre ated SSPR can be safely reused as roadbed materials,concrete and cement *** study provides a useful implication in treatment and beneficial reuse of heavy metal-containing hazardous wastes.

关键词： Stainless steel pickling residue Leaching toxicity Cr(Ⅵ) Chemical fixation Beneficial reuses

Prediction of Shear Bond Strength of Asphalt Concrete Pavement Using Machine Learning Models and Grid Search Optimization Technique

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Computer Modeling in engineering & Sciences 2025年第1期142卷 691-712页

作者： Quynh-Anh Thi Bui Dam Duc Nguyen Hiep Van Le Indra Prakash Binh Thai Pham civil engineering department University of Transport Technology54 Trieu KhucThanh XuanHanoi100000Vietnam DDG(R)Geological Survey of India Gandhinagar382010India

Determination of Shear Bond strength(SBS)at interlayer of double-layer asphalt concrete is crucial in flexible pavement *** study used three Machine Learning(ML)models,including K-Nearest Neighbors(KNN),Extra Trees(ET),and Light Gradient Boosting Machine(LGBM),to predict SBS based on easily determinable input ***,the Grid Search technique was employed for hyper-parameter tuning of the ML models,and cross-validation and learning curve analysis were used for training the *** models were built on a database of 240 experimental results and three input variables:temperature,normal pressure,and tack coat *** validation was performed using three statistical criteria:the coefficient of determination(R2),the Root Mean Square Error(RMSE),and the mean absolute error(MAE).Additionally,SHAP analysis was also used to validate the importance of the input variables in the prediction of the *** show that these models accurately predict SBS,with LGBM providing outstanding ***(Shapley Additive explanation)analysis for LGBM indicates that temperature is the most influential factor on ***,the proposed ML models can quickly and accurately predict SBS between two layers of asphalt concrete,serving practical applications in flexible pavement structure design.

关键词： Shear bond asphalt pavement grid search optimization machine learning

DO OCCUPANTS IN GREEN BUILDINGS PRACTICE BETTER ENERGY SAVING BEHAVIOUR IN COMPUTER USAGE THAN OCCUPANTS IN CONVENTIONAL BUILDINGS?

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Journal of Green Building 2015年第4期10卷 178-193页

作者： Nurul Sakina Mokhtar Azizi Suzanne Wilkinson Elizabeth Fassman department of civil&environmental engineering Faculty of Engineering University of Auckland

Green buildings are not entirely successful in achieving energy saving *** way of improving energy targets is to encourage occupants to adopt energy saving *** date,energy saving behaviour has been given less focus in improving green building performance than other energy saving initiatives,such as retrofitting buildings for green *** study uses comparison case studies between green buildings and conventional buildings in New Zealand to better understand the energy saving behaviour of *** were distributed to occupants in green and conventional buildings to evaluate the extent of energy saving behaviour practiced and to identify potential strategies to encourage energy saving *** objective of this paper is to investigate the level of energy saving behaviour between green and conventional office buildings to see if people in green buildings perform better energy saving behaviour than people in conventional buildings in computer *** findings do show better energy saving behaviour from occupants in green buildings than occupants in conventional *** paper shows why this is the *** recommended strategies to encourage energy saving behaviour used by different buildings are also *** include raising education awareness on energy efficiency among the building occupants,energy saving commitments,and to have an active building manager assigned for energy related matters.

关键词： energy saving behaviour energy efficiency green buildings conventional buildings

Aligned Ion Conduction Pathway of Polyrotaxane‑Based Electrolyte with Dispersed Hydrophobic Chains for Solid‑State Lithium–Oxygen Batteries

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Nano-Micro Letters 2025年第2期17卷 169-186页

作者： Bitgaram Kim Myeong‑Chang Sung Gwang‑Hee Lee Byoungjoon Hwang Sojung Seo Ji‑Hun Seo Dong‑Wan Kim department of Materials Science and engineering Korea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea School of civil Environmental and Architectural EngineeringKorea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea Materials Science and Chemical engineering Center Institute for Advanced Engineering(IAE)Yongin 17180Republic of Korea

A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety *** study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves ***-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain *** this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 *** situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen *** situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability *** present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.

关键词： Solid polymer electrolyte Lithium-oxygen batteries Polyrotaxane ion conductivity Hydrophobic chain

Spatiotemporal shoreline change in Boushehr Province coasts,Iran

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Journal of Oceanology and Limnology 2020年第3期38卷 707-721页

作者： Saeed ZEINALI Nasser TALEBBEYDOKHTI Maryam DEHGHANI department of civil&environmental engineering School of EngineeringShiraz UniversityShiraz 71348-51156Iran

Since coastal areas have highly dynamic nature and are one of the most beneficial regions of civilizations,it is of great significance to understand their characteristics and *** in shorelines in the form of accretion and erosion can leave devastating effects on businesses and cities located along the *** this study,we statistically calculated the tendency of shoreline changes by processing and analyzing historical satellite images of Boushehr Province,*** show that these shores have experienced both sedimentation and erosion in the past 30 *** shoreline movement presents more than 350 m of erosion and 650 m of accretion,which are corresponded to change rates of almost 12 and 22 m/a,*** of shoreline changes are calculated from regression methods including end point rate,linear regression rate,weighted linear regression,and least median of *** best-performed method is applied to predict the shoreline position in 2050 and *** locations of excessive changes are identified for the predicted shorelines,which should be dealt with properly.

关键词： digital shoreline analysis system satellite image accretion and erosion linear regression sediment Boushehr Province

Finite element implementation of strain-hardening Drucker-Prager plasticity model with application to tunnel excavation

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Underground Space 2017年第3期2卷 168-174页

作者： K.Liu S.L.Chen department of civil&environmental engineering Louisiana State UniversityBaton RougeLAUSA

This paper presents a finite element implementation of a strain-hardening Drucker-Prager model and its application to tunnel *** computational model was constructed based on the return mapping scheme,in which an elastic trial step was first executed,followed by plastic correction involving the Newton-Raphson method to return the predicted state of stresses to the supposed yield *** combining the plastic shear hardening rule and stress correction equations,the loading index for the strain-hardening Drucker-Prager model was *** is therefore possible to update the stresses,elastic and plastic strains,and slope of the yield locus at the end of each incremental *** an illustrative example,an integration algorithm was incorporated into ABAQUS through the user subroutine UMAT to solve the tunnel excavation problem in strain-hardening Drucker-Prager rock *** obtained numerical results were found to be in excellent agreement with the available analytical solutions,thus indicating the validity and accuracy of the proposed UMAT code,as well as the finite element model.

关键词： Strain-hardening Drucker-Prager model Finite element method UMAT code Tunnel excavation

A plasticity model for sand-structure interfaces

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Journal of Central South University 2012年第4期19卷 1098-1108页

作者： A.Lashkari department of civil&environmental engineering Shiraz University of TechnologyShiraz 71555-313Iran

The predictive capacity of numerical analyses in geotechnical engineering depends strongly on the efficiency of constitutive models used for modeling of interfaces *** are considered as thin layers of the soil adjacent to structures boundary whose major role is transferring loads from structures to soil *** interface model within the bounding surface plasticity framework and the critical state soil mechanics is *** this aim,general formulation of the interface model according to the bounding surface plasticity theory is described *** to granular soils,it has been shown that the mechanical behavior of sand-structure interfaces is highly affected by the interface state that is the combined influences of density and applied normal ***,several ingredients of the model are directly related to the interface *** a result of this feature,the model is enabled to distinguish interfaces in dense state from those in loose state and to provide realistic predictions over wide ranges of density and normal stress *** evaluation of the model,a reasonable correspondence between the model predictions and the experimental data of various research teams is found.

关键词： soil-structure interface sand dilatancy bounding surface plasticity

Determination and prediction of pavement skid resistance–connecting research and practice

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Journal of Road engineering 2021年第1期1卷 43-62页

作者： T.F.Fwa department of civil&environmental engineering National University of SingaporeSingapore 117576Singapore

Adequate pavement skid resistance is a key requirement for safe road ***,the measurement and prediction of the skid resistance property of an in-service road pavement,or pavement mixture specimens in the laboratory,is a highly challenging process from both theoretical and practical points of *** more than 60 years,owing to the lack of theoretical solutions to the complex tire-fluid-pavement interaction problem,the practice of pavement skid resistance determination and prediction has essentially been derived from experimental and field observed *** rapid development of efficient numerical computational techniques and high-power computing facilities in the last two decades made it possible for researchers to numerically solve the tire-fluidpavement interaction *** enables the numerical evaluation and prediction of high-speed wet skid resistance,and the determination of the tire-pavement kinetic friction coefficient in the evaluation of low-speed skid *** paper presents a state-of-the-art review of the research development of theoretical mechanistic approaches in the determination and prediction of pavement skid *** covers the following main aspects of the subject matter:(i)mechanisms of skid resistance generation in dry,wetted(i.e.,damp),wet and flooded pavements;(ii)theoretical evaluation of pavement skid resistance in dry,wetted,wet and flooded states;(iii)theoretical approaches in pavement skid resistance prediction;and(iv)concepts of representing the skid resistance state of *** capability of finite element simulation approach for wet skid resistance evaluation with good accuracy is *** highlighted is the practical significance of the Concept of Skid Resistance *** of practical applications of the concept,coupled with the simulation model,are *** include applications in driving safety analysis,road safety design and control,design of paving mixtures,safety mainte

关键词： Skid resistance Tire-fluid-pavement interaction Coefficient of kinetic friction Microtexture Macrotexture Pavement friction management

Salinity exchange between seawater/brackish water and domestic wastewater through electrodialysis for potable water

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Frontiers of environmental Science & engineering 2023年第2期17卷 19-28页

作者： Mourin Jarin Zeou Dou Haiping Gao Yongsheng Chen Xing Xie School of civil&environmental engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Two-thirds of the world’s population has limited access to potable *** we continue to use up our freshwater resources,new and improved techniques for potable water production are ***,we present a general concept called“salinity exchange”that transfers salts from seawater or brackish water to treated wastewater until their salinity values approximately switch,thus producing wastewater with an increased salinity for discharge and desalinated seawater as the potable water *** have demonstrated this process using *** exchange has been successfully achieved between influents of different salinities under various operating ***-scale salinity exchange electrodialysis(SEE)systems can produce high-quality desalinated water at~1 mL/min with an energy consumption less than 1 kWh/*** has also been operated using real water,and the challenges of its implementation at a larger scale are evaluated.

关键词： Desalination Potable water reuse Ion-exchange membrane Salinity gradient energy Wastewater discharge

COVID-19 transmission in *** buses:A scenario-based approach with agent-based simulation modeling(ABSM)

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Communications in Transportation Research 2023年第1期3卷 72-80页

作者： Sachraa G.Borjigin Qian He Deb A.Niemeier department of civil&environmental engineering University of MarylandCollege ParkMD20742USA

The transit bus environment is considered one of the primary sources of transmission of the COVID-19(SARSCoV-2)*** disease transmission in public buses remains a challenge,especially with uncertainties in passenger boarding,alighting,and onboard *** there are initial findings on the effectiveness of some of the mitigation policies(such as face-covering and ventilation),evidence is scarce on how these policies could affect the onboard transmission risk under a realistic bus setting considering different headways,boarding and alighting patterns,and seating capacity *** study examines the specific policy regimes that transit agencies implemented during early phases of the COVID-19 pandemic in USA,in which it brings crucial insights on combating current and future *** use an agent-based simulation model(ABSM)based on standard design characteristics for urban buses in USA and two different service frequency settings(10-min and 20-min headways).We find that wearing face-coverings(surgical masks)significantly reduces onboard transmission rates,from no mitigation rates of 85%in higher-frequency buses and 75%in lower-frequency buses to 12.5%.The most effective prevention outcome is the combination of KN-95 masks,open window policies,and half-capacity seating control during higher-frequency bus services,with an outcome of nearly 0%onboard infection *** results advance understanding of COVID-19 risks in the urban bus environment and contribute to effective mitigation policy design,which is crucial to ensuring passenger *** findings of this study provide important policy implications for operational adjustment and safety protocols as transit agencies seek to plan for future emergencies.

关键词： COVID-19 Transit buses Indoor transmission Mitigation strategies Agent-based simulation modeling(ABSM)