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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 60-70页

作者： Hai Li Aibing Jin Shuaijun Chen Yiqing Zhao You Ju Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mine University of Science and Technology BeijingBeijing 100083China school of civil and resources engineering University of Science and Technology BeijingBeijing 100083China

The challenge of high temperatures in deep mining remains harmful to the health of workers and their production efficiency The addition of phase change materials (PCMs) to filling slurry and the use of the cold storage function of these materials to reduce downhole temperatures is an effective approach to alleviate the aforementioned ***–CaCl_(2)·6H_(2)O composite PCM was prepared in the *** composition,phase change latent heat,thermal conductivity,and cemented tailing backfill (CTB) compressive strength of the new material were *** heat transfer characteristics and endothermic effect of the PCM were simulated using Fluent *** results showed the following:(1) The new paraffin–CaCl_(2)·6H_(2)O composite PCM improved the thermal conductivity of native paraffin while avoiding the water solubility of CaCl_(2)·6H_(2)O.(2) The calculation formula of the thermal conductivity of CaCl_(2)·6H_(2)O combined with paraffin was deduced,and the reasons were explained in principle.(3) The“enthalpy–mass scale model”was applied to calculate the phase change latent heat of nonreactive composite PCMs.(4)The addition of the paraffin–CaCl_(2)·6H_(2)O composite PCM reduced the CTB strength but increased its heat absorption *** research can give a theoretical foundation for the use of heat storage backfill in green mines.

关键词： paraffin–CaCl_(2)·6H_(2)O heat transfer simulation heat calculation phase change material-based backfill latent heat of formula

Blast damage zone strength reduction method for deep cavern excavation and its application

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Frontiers of Structural and civil engineering 2024年第2期18卷 236-251页

作者： Tianzhi YAO Zuguo MO Li QIAN Yunpeng GAO Jianhai ZHANG Xianglin XING Enlong LIU Ru ZHANG State Key Laboratory of Hydraulics and Mountain River engineering College of Water Resources and HydropowerSichuan UniversityChengdu 610065China Power China Chengdu engineering Corporation Limited Chengdu 610072China

The drill and blast(D&B)method is widely used to excavate underground spaces,but explosions generally cause damage to the ***,no blast simulation method can provide computational accuracy and *** this paper,a blast equivalent simulation method called the blast damage zone strength reduction(BDZSR)method is *** method first calculates the range of the blast-induced damage zone(BDZ)by formulae,then reduces the strength and deformation parameters of the rock within the BDZ ahead of excavation,and finally calculates the excavation damage zone(EDZ)for the D&B method by numerical *** method combines stress wave attenuation,rock damage criteria and stress path variation to derive the BDZ depth calculation *** formulae consider the initial geo-stress,and the reliability is verified by numerical *** calculation of BDZ depth with these formulae allows the corresponding numerical simulation to avoid the time-consuming dynamic calculation process,thus greatly enhancing the calculation *** method was applied to the excavation in Jinping Class II hydropower station to verify its *** results show that the BDZSR method can be applied to blast simulation of underground caverns and provide a new way to study blast-induced damage.

关键词： attenuation of stress wave deep-buried underground building drill and blast in situ stress

An Optimized System of Random Forest Model by Global Harmony Search with Generalized Opposition-Based Learning for Forecasting TBM Advance Rate

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Computer Modeling in engineering & Sciences 2024年第3期138卷 2873-2897页

作者： Yingui Qiu Shuai Huang Danial Jahed Armaghani Biswajeet Pradhan Annan Zhou Jian Zhou school of resources and Safety engineering Central South UniversityChangsha410083China school of civil and Environmental engineering University of Technology SydneyNew South WalesAustralia Centre for Advanced Modelling and Geospatial Information Systems School of Civil and Environmental EngineeringFaculty of Engineering and Information TechnologyUniversity of Technology SydneyNew SouthWalesAustralia civil and Infrastructure engineering Discipline School of EngineeringRoyal Melbourne Institute of Technology(RMIT)MelbourneVictoria3001Australia

As massive underground projects have become popular in dense urban cities,a problem has arisen:which model predicts the best for Tunnel Boring Machine(TBM)performance in these tunneling projects?However,performance level of TBMs in complex geological conditions is still a great challenge for practitioners and *** the other hand,a reliable and accurate prediction of TBM performance is essential to planning an applicable tunnel construction *** performance of TBM is very difficult to estimate due to various geotechnical and geological factors and machine *** previously-proposed intelligent techniques in this field are mostly based on a single or base model with a low level of ***,this study aims to introduce a hybrid randomforest(RF)technique optimized by global harmony search with generalized oppositionbased learning(GOGHS)for forecasting TBM advance rate(AR).Optimizing the RF hyper-parameters in terms of,e.g.,tree number and maximum tree depth is the main objective of using the GOGHS-RF *** the modelling of this study,a comprehensive databasewith themost influential parameters onTBMtogetherwithTBM AR were used as input and output variables,*** examine the capability and power of the GOGHSRF model,three more hybrid models of particle swarm optimization-RF,genetic algorithm-RF and artificial bee colony-RF were also constructed to forecast TBM *** of the developed models was performed by calculating several performance indices,including determination coefficient(R2),root-mean-square-error(RMSE),and mean-absolute-percentage-error(MAPE).The results showed that theGOGHS-RF is a more accurate technique for estimatingTBMAR compared to the other applied *** newly-developedGOGHS-RFmodel enjoyed R2=0.9937 and 0.9844,respectively,for train and test stages,which are higher than a pre-developed ***,the importance of the input parameters was interpreted through the SHapley Additive exPlanations(SHA

关键词： Tunnel boring machine random forest GOGHS optimization PSO optimization GA optimization ABC optimization SHAP

Removal of pathogenic indicator microorganisms during partial nitrification:the role of free nitrous acid

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Frontiers of Environmental Science & engineering 2024年第3期18卷 93-102页

作者： Jiaojiao Xu Xiaotian Chen Rui Tang Jingwei Feng Shoujun Yuan Wei Wang Zhen-Hu Hu Anhui engineering Laboratory of Rural water Environment and Resource School of Civil EngineeringHefei University of TechnologyHefei 230009China Hefei 168 High school Hefei 230025China Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric PowerShanghai 200090China

Digested wastewater contains pathogenic microorganisms and high ammonia concentrations,which can pose a potential risk to public *** removal of pathogens and nitrogen is crucial for the post-treatment of digested *** nitrification-anammox is an energy-saving nitrogen removal *** nitrous acid(FNA),an intermediate product of partial nitrification,has the potential to inactivate ***,the efficiency and mechanisms of FNA-related inactivation in pathogens during partial nitrification remains *** this study,Enterococcus and Escherichia coli(***)were selected to investigate the efficiency and mechanisms of FNA-related inactivation in partial nitrification *** results revealed that 83%±13%and 59%±27%of *** and Enterococcus were removed,respectively,in partial nitrification process at FNA concentrations of 0.023−0.028 mg/*** the concentration of FNA increased from 0 to 0.5 mg/L,the inactivation efficiencies of *** and Enterococcus increased from 0 to 99.9%and 89.9%,*** exhibited a higher resistance to FNA attack compared to ***.3D-laser scanning microscopy(3D-LSM)and scanning electron microscopy(SEM)revealed that FNA exposure caused the surface collapse of *** and Enterococcus,as well as visible pore formation on the surface of *** cells.4',6-Diamidino-2-phenylindole dihydrochloride n-hydrate(DAPI)/propidium iodide(PI)and biomolecule leakage confirmed that inactivation of *** and Enterococcus occurred due to breakdown of cell walls and cell *** findings indicate that partial nitrification process can be used for the removal of residual pathogenic microorganisms.

关键词： Partial nitrification Free nitrous acid Pathogenic indicator microorganism Inactivation Cell structure

New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

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Frontiers of Environmental Science & engineering 2024年第2期18卷 161-168页

作者： Zhiqiang Zuo Min Zheng Tao Liu Yongzhen Peng Zhiguo Yuan National engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Engineering Research Center of BeijingBeijing University of TechnologyBeijing 100124China Australian Centre for water and Environmental Biotechnology The University of QueenslandSt.LuciaQLD 4072Australia water Research Centre School of Civil and Environmental EngineeringUniversity of New South WalesSydneyNew South Wales 2052Australia Department of civil and Environmental engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077China school of Energy and Environment City University of Hong KongHong Kong 999077China

The biocidal effects of free nitrous acid (FNA) have found applications in multiple units in an urban wastewater system, including sewer networks, wastewater treatment processes, and sludge treatment processes. However, these applications are associated with chemical costs as both nitrite and acid are needed to produce FNA at the required levels. The recent discovery of novel acid-tolerant ammonia oxidizers offers the possibility to produce FNA from domestic wastewater, enabling the development of next-generation FNA-based technologies capable of achieving self-sustaining FNA production. In this study, we focus on the concept of in situ FNA generation facilitated by acid-tolerant ammonia oxidizers and highlight the multiple benefits it creates, after a brief review of the historical development of FNA-based technologies. We will discuss how wastewater systems can be made more energy-efficient and sustainable by leveraging the potential of acid-tolerant ammonia oxidizers.

关键词： Free nitrous acid Acid-toler antammonia oxidizer In situ generationl Wastewater management

Predicting the International Roughness Index of JPCP and CRCP Rigid Pavement:A Random Forest(RF)Model Hybridized with Modified Beetle Antennae Search(MBAS)for Higher Accuracy

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Computer Modeling in engineering & Sciences 2024年第5期139卷 1557-1582页

作者： Zhou Ji Mengmeng Zhou Qiang Wang Jiandong Huang College of civil and Environmental engineering Hunan University of Science and EngineeringYongzhou425006China school of Mines China University of Mining and TechnologyXuzhou221116China school of civil engineering Guangzhou UniversityGuangzhou510006China

To improve the prediction accuracy of the International Roughness Index(IRI)of Jointed PlainConcrete Pavements(JPCP)and Continuously Reinforced Concrete Pavements(CRCP),a machine learning approach is developed in this study for the modelling,combining an improved Beetle Antennae Search(MBAS)algorithm and Random Forest(RF)*** 10-fold cross-validation was applied to verify the reliability and accuracy of the model proposed in this *** importance scores of all input variables on the IRI of JPCP and CRCP were analysed as *** results by the comparative analysis showed the prediction accuracy of the IRI of the newly developed MBAS and RF hybrid machine learning model(RF-MBAS)in this study is higher,indicated by the RMSE and R values of 0.2732 and 0.9476 for the JPCP as well as the RMSE and R values of 0.1863 and 0.9182 for the *** accuracy of this obtained result far exceeds that of the IRI prediction model used in the traditional Mechanistic-Empirical Pavement Design Guide(MEPDG),indicating the great potential of this developed *** importance analysis showed that the IRI of JPCP and CRCP was proportional to the corresponding input variables in this study,including the total joint faulting cumulated per KM(TFAULT),percent subgrade material passing the 0.075-mm Sieve(P_(200))and pavement surface area with flexible and rigid patching(all Severities)(PATCH)which scored higher.

关键词： Cement pavement JPCP CRCP RF-MBAS IRI

Comprehensive insight into the occurrence characteristics,influencing factors and risk assessments of antibiotics in the Chaohu Basin

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Frontiers of Environmental Science & engineering 2024年第5期18卷 57-71页

作者： Shuanggang Hu Hongzhi Zhang Yongjie Yang Kangping Cui Junjie Ao Xuneng Tong Mengchen Shi Yi Wang Xing Chen Chenxuan Li Yihan Chen school of resources and Environmental engineering Hefei University of TechnologyHefei230009China Ministry of Education-Shanghai Key Laboratory of Children’s Environmental Health Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai200092China Department of civil & Environmental engineering National University of SingaporeSingapore117576Singapore College of resources and Environment Anhui Agricultural UniversityHefei230036China

The pollution of antibiotics in aquatic environments has received extensive ***,research on antibiotic contamination in river-lake systems,a significant form of modern aquatic environments,still needs to be *** study focuses on the Chaohu Basin(China)investigating the occurrence characteristics,influencing factors,and risk assessments of antibiotics in the river-lake *** total antibiotic concentrations in the water phase and sediment phase were 3.14–1887.49 ng/L and 0.92–1553.75 ng/g,*** was the predominant antibiotic in the water phase,whereas tetracycline prevailed in the sediment *** differences in concentration and structural composition of antibiotics between the tributaries(river system)and Chaohu Lake were observed,indicating the involvement of various geochemical processes in the attenuation of antibiotics during transport to the receiving *** analysis suggested that the western river is the primary source of antibiotics in Chaohu *** nutrient influx in heavily polluted areas is crucial to addressing the escalating issue of antibiotic pollution in the river-lake *** widespread occurrence of clindamycin in the waters is likely due to wastewater treatment plant discharges,and high-intensity human activities continue to exacerbate antibiotic *** assessment indicated that sulfamethoxazole,tetracycline,lincomycin,and clindamycin ranked in the top four with the highest risks to the most sensitive aquatic ***,the antibiotics presented no risk to consumer *** study provides valuable insights for controlling antibiotic pollution in riverlake systems.

关键词： Antibiotics Occurrence characteristics Influencing factors Risk assessments River-lake system

Fine particle trace elements at a mountain site in southern China:Source identification,transport,and health risks

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Journal of Environmental Sciences 2024年第7期141卷 166-181页

作者： Jiaoping Xing Runping Ding Feifeng Chen Linyu Peng Wenhua Wang Xiaoyan Song Qing Ye Yuanqiu Liu Key Laboratory of State Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake watershed School of ForestryJiangxi Agricultural UniversityNanchang 330045China school of resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China College of Geosciences and engineering North China University of Water Resources&Electric PowerZhengzhou 450046China

Trace elements in atmospheric particulate matter play a significant role in air quality,human health,and biogeochemical *** this study,the trace elements(Ca,Al,K,Fe,Na,Mg,Zn,Pb,Mn,Ti,Cu,Cr,Sr,Ni)in PM2.5samples collected at the summit of *** were analyzed to quantify their abundance,source,transport,and health *** the whole sampling period,the major trace elements was Ca,Al,and *** the trace metals with the lowest concentrations were Sr,Ni,Rb,and *** trace elements were influenced by air mass transport routes,exhibiting an increasing trend of crustal elements in the northwesterly airmass and anthropogenic elements(Zn,Mn,Cu,and Ni)in the easterly air *** dust,coal+biomass burning,vehicle emission,urban nitrate-rich+urban waste incineration emissions,and soil dust+industry emissions were common sources of PM2.5on *** air mass transport routes had various source contribution *** results indicate that trace elements at *** are influenced by regional anthropogenic emissions and monsoon-dominated trace element *** total resulting cancer risk value that these elements posed were below the acceptable risk value of 1×10^(-6),while the non-carcinogenic risk value(1.72)was higher than the safety level,suggesting that non-carcinogenic effects due to these trace elements inhalation were likely to *** emission and coal+biomass burning were the common dominant sources of non-cancer risks posed by trace elements at ***.

关键词： Trace elements Risk assessment Cluster analysis Source apportionment

Numerical Exploration of Asymmetrical Impact Dynamics: Unveiling Nonlinearities in Collision Problems and Resilience of Reinforced Concrete Structures

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Structural Durability & Health Monitoring 2024年第3期18卷 223-254页

作者： AL-Bukhaiti Khalil Yanhui Liu Shichun Zhao Daguang Han school of civil engineering Southwest Jiaotong UniversityChengdu610031China Faculty of civil engineering Southeast UniversityNanjingChina

This study provides a comprehensive analysis of collision and impact problems’ numerical solutions, focusing ongeometric, contact, and material nonlinearities, all essential in solving large deformation problems during a *** initial discussion revolves around the stress and strain of large deformation during a collision, followedby explanations of the fundamental finite element solution method for addressing such issues. The hourglassmode’s control methods, such as single-point reduced integration and contact-collision algorithms are detailedand implemented within the finite element framework. The paper further investigates the dynamic responseand failure modes of Reinforced Concrete (RC) members under asymmetrical impact using a 3D discrete modelin ABAQUS that treats steel bars and concrete connections as bond slips. The model’s validity was confirmedthrough comparisons with the node-sharing algorithm and system energy relations. Experimental parameterswere varied, including the rigid hammer’s mass and initial velocity, concrete strength, and longitudinal and stirrupreinforcement ratios. Findings indicated that increased hammer mass and velocity escalated RC member damage,while increased reinforcement ratios improved impact resistance. Contrarily, increased concrete strength did notsignificantly reduce lateral displacement when considering strain rate effects. The study also explores materialnonlinearity, examining different materials’ responses to collision-induced forces and stresses, demonstratedthrough an elastic rod impact case study. The paper proposes a damage criterion based on the residual axialload-bearing capacity for assessing damage under the asymmetrical impact, showing a correlation betweendamage degree hammer mass and initial velocity. The results, validated through comparison with theoreticaland analytical solutions, verify the ABAQUS program’s accuracy and reliability in analyzing impact problems,offering valuable insights into collision

关键词： Geometric nonlinearity contact nonlinearity material nonlinearity collision problems finite element method stress and strain damage criterion RC members asymmetrical impact

J/ψ pair hadroproduction at next-to-leading order in nonrelativistic-QCD at ATLAS

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Chinese Physics C 2024年第3期48卷 15-19页

作者：孙立平 school of Science Beijing University of Civil Engineering and ArchitectureBeijingChina

We present a complete study on the J/ψpair hadroproduction at next-to-leading order(NLO)in the nonrelativstic-QCD(NRQCD)framework with the pair of cc¯in either ^(3)S^([1])_(1) or ^(1)S^([8])_(0) fock *** found that the contribution of the ^(1)S^([8])_(0) channel at NLO is essential,and for ATLAS,the NRQCD results can describe the experimental data to a certain extent.

关键词： NRQCD next-to-leading order ATLAS fock state