检索结果-内蒙古大学图书馆

Intensifying intermittent aeration for optimizing nutrient and hormone removal in vertical-flow constructed wetlands filled with aerated concrete

引用

Chemosphere 2025年 370卷 143941页

作者： Donato, Mayra Alves de Oliveira Souza, Adelania Pacheco, Amanda de Carvalho Silva, Lucas Svenar, Silvana Nagalli, André Passig, Fernando Hermes Brasil Bernardelli, Jossy Karla Querne de Carvalho, Karina - Civil Engineering Graduate Program. Deputado Heitor de Alencar Furtado St. 5000 Ecoville Paraná Curitiba81280-340 Brazil – Environmental Sciences and Technology Graduate Program. Deputado Heitor de Alencar Furtado St. 5000 Ecoville Paraná Curitiba81280-340 Brazil - Civil Construction Academic Department Deputado Heitor de Alencar Furtado St. 5000 Ecoville Paraná Curitiba81280-340 Brazil - Biology and Chemistry Academic Department. Deputado Heitor de Alencar Furtado St. 5000 Ecoville Paraná Curitiba81280-340 Brazil

Operational strategies have been applied in constructed wetlands to optimize the removal of nutrients and hormones that are still a concern in wastewater treatment. The strategy of intensifying intermittent aeration was investigated in two microcosm-scale vertical-flow constructed wetlands (VFCWs) planted with Eichhornia crassipes onto autoclaved aerated concrete (AC) in the removal of nutrients, estrone (E1), 17β-estradiol (E2) and 17α-ethinylestradiol (EE2). CW-1 (2.4 LO2 min−1) and CW-2 (1.4 LO2 min−1) were fed with synthetic wastewater in sequencing-batch mode (cycles 48-48-72 h) and intermittently aerated for 1 h, followed by 7 h without aeration for 377 days. Combined with the intensification strategy, the use of planted free-floating macrophytes and concrete-based material (emergent) as filtering media stand out as the innovation and originality aspects of this study. Despite the hormone addition, intensifying aeration enhanced the efficiencies since CW-1 achieved the highest removals with 91% COD, 77% TN, 74% TAN, 60% nitrate, and 97% TP in Stage I (no hormone addition) and 90% COD, 80% TN, 93% TAN, 63% nitrate, and 82% TP in Stage II (with hormone addition). CW-1 achieved the highest removal efficiencies of E1 (84%), E2 (95%), and EE2 (73%). Conversely, the efficiencies decreased under the lower aeration rate (in CW-2) for all parameters. Macrophyte uptake and adsorption stood out for TN (>60.25%) and TP (>27.6%) removal as the main mechanisms in the VFCWs. The characteristics of AC favored ion exchange and precipitation, reinforcing the potential of this material as filtering media in VFCWs. Intensification of intermittent aeration combined with hormone addition diverse and riched the microbial community with the presence of Thauera, Lentimicrobium (denitrification), Candidatus Accumulibacter (phosphorus removal), Pseudomonas, Fusibacter, and Azoarcus (EE2 degradation). Intensifying intermittent aeration was an important strategy to enhance the simultaneou

关键词： Wastewater treatment

来源：评论

学校读者我要写书评

暂无评论

STRUCTURAL ASSESSMENT OF COMPOSITE HIGHWAY BRIDGES CONSIDERING VEHICLE-BRIDGE DYNAMIC INTERACTION

引用

ce/papers 2024年第1-2期7卷 165-174页

作者： da Silva, Ana Célia Soares Alencar, Guilherme Santana da Silva, José Guilherme Santos Civil Engineering Post-graduate Program [PGECIV/UERJ Brazil Brazil Brazil

Over time, as the bridge deck pavement deterioration process increases, the calculated vertical translational displacements and stresses are higher. In this context, the chances of mechanical failure occurrence increase and may cause limitation in the service life of steel and composite (steel-concrete) bridges. Thus, the current work presents a methodology for fatigue analysis developed by the authors through the years. The methodology is devoted specifically for the assessment of composite bridges employing the hot-spot local S-N approach and a coupled vehicle-pavement-bridge system considering progressive pavement deterioration with stochastically generated roughness profiles. © 2024 Ernst & Sohn GmbH.

关键词： Deterioration

来源：评论

学校读者我要写书评

暂无评论

Development of ceramic membranes from sugarcane bagasse ash for microfiltration of biodiesel production effluents

Open Ceramics

引用

Open Ceramics 2025年 22卷

作者： Pin, Clarissa Ferreira Brandler, Danieli Flores, Gabriela Cristina Perusin Kubiaki Levandoski, William Mateus Bruschi, Giovani Jordi Pelissaro, Deise Trevizan Dervanoski, Adriana Korf, Eduardo Pavan Pasquali, Gean Delise Leal Graduate Program in Enviromental Science and Technology Federal University of Fronteira Sul Erechim/RS 99700-970 Brazil Departament of Civil Engineering Integrated Regional University of Alto Uruguai and Missões – Erechim/RS 99709-910 Brazil Departament of Environmental and Sanitary Engineering Federal University of Fronteira Sul Erechim/RS 99700-970 Brazil

Ceramic membranes have emerged as a promising solution for microfiltration processes, offering advantages such as cost-effectiveness, environmental benefits, and the utilization of abundant raw materials derived from agro-industrial solid waste. This study investigates the fabrication and performance of ceramic membranes composed of kaolin the varying proportions of sugarcane bagasse ash (SCBA - 40 wt % and 60 wt %), with focus on efficiency in treating biodiesel wastewater. The membranes were characterized (porosity, average pore diameter, and mechanical strength). The membrane containing 40 wt % SCBA - employed without any pre-treatment- exhibited the best overall performance, achieving porosity of 38.5 %, an pore diameter of 0.9 µm, and mechanical strength of 27 MPa, indicating a favorable balance between permeability and structural integrity. The best-performing membrane achieved removal efficiencies of color 83 % and turbidity 67 %. Microstructural analysis revealed a network of interconnected mesopores, which are particularly effective for the retention of colloidal and suspended contaminants. © 2025 The Authors

关键词： Agro-industrial solid waste Industrial effluent Membrane filtration

来源：评论

学校读者我要写书评

暂无评论

Microalgae biotechnology applied to wastewater treatment and biopolymer production: A sustainable alternative for resource recovery

引用

Journal of Water Process engineering 2025年 75卷

作者： Assemany, Paula de Souza, Isabelly L. Muchico, Joaquina da Márcia J. Scalco, Kaique M.F.C. Balbino, Marcos Vinícius M. Santurbano, Victor Nascimento, Lívia C. da Paz de Oliveira, Otávio N. Siniscalchi, Luciene A.B. Post-Graduate Program in Environmental Engineering Federal University of Lavras (Universidade Federal de Lavras) MG Brazil Department of Environmental Engineering Federal University of Lavras (Universidade Federal de Lavras) MG Brazil

Cultivating microalgae in wastewater offers the dual benefit of efficiently removing pollutants while generating biomass suitable for high-value bioplastics, thus supporting the principles of a circular bioeconomy. Despite this potential, integrating microalgae cultivation for biopolymer obtention into wastewater treatment remains unresolved. Unlike existing reviews, this manuscript primarily aims to explore effective large-scale strategies for accumulating valuable compounds such as polysaccharides, proteins, and polyhydroxyalkanoates from biomass within a wastewater treatment plant context. It addresses the main routes for obtaining biopolymers through the valorization of microalgae biomass, emphasizing a comprehensive approach that blends biomass with other plastic sources, employs two-stage anaerobic digestion, and recovers organic acids for polyhydroxyalkanoate production alongside operational strategies to enhance biomass quality. High-rate algal ponds arranged in series and a two-stage cultivation process are proposed as promising operational strategies to increase the value of biomass for biopolymer production. Key challenges include scalable production processes and improved economic viability to encourage wider industry adoption. The manuscript also offers insights for enhancing the sustainability performance of bioplastics, emphasizing the need to tackle the social and environmental impacts, the last derived from low biodegradability and toxicity due to additives and solvents. Regulatory and public policies, along with transforming wastewater treatment plants into wastewater biorefineries, are also crucial factors in making the technology more commercially feasible. By consolidating current research, this review aims to promote sustainable strategies through microalgal applications that optimize environmental and economic outcomes. © 2025 Elsevier Ltd

关键词： Algal biomass valorization Biopolymer Green plastics Wastewater treatment

来源：评论

学校读者我要写书评

暂无评论

Application of machine learning technique for predicting and evaluating chloride ingress in concrete

引用

Frontiers of Structural and civil engineering 2022年第9期16卷 1153-1169页

作者： Van Quan TRAN Van Loi GIAP Dinh Phien VU Riya Catherine GEORGE Lanh Si HO Department of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

The degradation of concrete structure in the marine environment is often related to chloride-induced corrosion of reinforcement ***,the chloride concentration in concrete is a vital parameter for estimating the corrosion level of reinforcement *** research aims at predicting the chloride content in concrete using three hybrid models of gradient boosting(GB),artificial neural network(ANN),and random forest(RF)in combination with particle swarm optimization(PSO).The input variables for modeling include exposure condition,water/binder ratio(W/B),cement content,silica fume,time exposure,and depth of *** results indicate that three models performed well with high accuracy of prediction(R2⩾0.90).Among three hybrid models,the model using GB_PSO achieved the highest prediction accuracy(R2=0.9551,RMSE=0.0327,and MAE=0.0181).Based on the results of sensitivity analysis using SHapley Additive exPlanation(SHAP)and partial dependence plots 1D(PDP-1D),it was found that the exposure condition and depth of measurement were the two most vital variables affecting the prediction of chloride *** the number of different exposure conditions is larger than two,the exposure significantly impacted the chloride content of concrete because the chloride ion ingress is affected by both chemical and physical *** study provides an insight into the evaluation and prediction of the chloride content of concrete in the marine environment.

关键词： gradient boosting random forest chloride content concrete sensitivity analysis

来源：评论

学校读者我要写书评

暂无评论

Optimization of machine learning models for predicting the compressive strength of fiber-reinforced self-compacting concrete

引用

Frontiers of Structural and civil engineering 2023年第2期17卷 284-305页

作者： Hai-Van Thi MAI May Huu NGUYEN Son Hoang TRINH Hai-Bang LY Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

Fiber-reinforced self-compacting concrete(FRSCC)is a typical construction material,and its compressive strength(CS)is a critical mechanical property that must be adequately *** the machine learning(ML)approach to estimating the CS of FRSCC,the current research gaps include the limitations of samples in databases,the applicability constraints of models owing to limited mixture components,and the possibility of applying recently proposed *** study developed different ML models for predicting the CS of FRSCC to address these *** neural network,random forest,and categorical gradient boosting(CatBoost)models were optimized to derive the best predictive model with the aid of a 10-fold cross-validation technique.A database of 381 samples was created,representing the most significant FRSCC dataset compared with previous studies,and it was used for model *** findings indicated that CatBoost outperformed the other two models with excellent predictive abilities(root mean square error of 2.639 MPa,mean absolute error of 1.669 MPa,and coefficient of determination of 0.986 for the test dataset).Finally,a sensitivity analysis using a partial dependence plot was conducted to obtain a thorough understanding of the effect of each input variable on the predicted CS of *** results showed that the cement content,testing age,and superplasticizer content are the most critical factors affecting the CS.

关键词： compressive strength self-compacting concrete artificial neural network decision tree CatBoost

来源：评论

学校读者我要写书评

暂无评论

A hybrid machine learning model to estimate self-compacting concrete compressive strength

引用

Frontiers of Structural and civil engineering 2022年第8期16卷 990-1002页

作者： Hai-Bang LY Thuy-Anh NGUYEN Binh Thai PHAM May Huu NGUYEN Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

This study examined the feasibility of using the grey wolf optimizer(GWO)and artificial neural network(ANN)to predict the compressive strength(CS)of self-compacting concrete(SCC).The ANN-GWO model was created using 115 samples from different sources,taking into account nine key SCC *** validation of the proposed model was evaluated via six indices,including correlation coefficient(R),mean squared error,mean absolute error(MAE),IA,Slope,and mean absolute percentage *** addition,the importance of the parameters affecting the CS of SCC was investigated utilizing partial dependence *** results proved that the proposed ANN-GWO algorithm is a reliable predictor for SCC’s *** that,an examination of the parameters impacting the CS of SCC was provided.

关键词： artificial neural network grey wolf optimize algorithm compressive strength self-compacting concrete

来源：评论

学校读者我要写书评

暂无评论

Nitrite impairs bioreactor performance due to decreased replication of Candidatus Brocadia sapporoensis by unbalanced energy allocation

引用

Water Research 2025年 283卷 123806页

作者： Qiao, Xuejiao Zhang, Liyu Qiu, Zhiguang Wu, Yang Deng, Chunfang Geng, Yanni Zhang, Yichi Yan, Yan Li, Bing Zhang, Lijuan Zhuang, Wei-Qin Yu, Ke Eco-environment and Resource Efficiency Research Laboratory School of Environment and Energy Peking University Shenzhen Graduate School Guangdong Shenzhen518055 China -Preferred Program Peking University Shenzhen518055 China State Key Laboratory of Isotope Geochemistry CAS Center for Excellence in Deep Earth Science Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangdong Guangzhou510000 China Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery Tsinghua Shenzhen International Graduate School Tsinghua University Shenzhen518055 China Department of Civil and Environmental Engineering The University of Auckland Auckland New Zealand

The effects of nitrite on anammox activities have been extensively studied. However, the molecular mechanisms of specific microorganisms responding to nitrite in anammox systems remain unexplored. This study investigates how excessive nitrite affects the core metabolisms of AnAOB and symbiotic bacteria, further elucidating the mechanisms by which it regulates microbial growth and nitrogen removal performance. Specifically, the nitrogen removal process in a continuous-flow anammox membrane bioreactor collapsed when the nitrite concentration reached 243 mg N/L. Integrated meta-omics analyses demonstrated that excessive nitrite disrupted the energy metabolism of Ca. Brocadia sapporoensis (AMXB1), reducing the energy available for developing tolerance. Subsequently, it disrupted cell replication by impairing the biosynthesis process of AMXB1, particularly DNA replication and the formation of vital cell structures such as the cell membrane and cell wall, as well as the cellular protection system, leading to the collapse of the anammox system. Additionally, the cross-feeding of amino acids and cofactors between AMXB1 and symbiotic bacteria plays an important role in the recovery of nitrogen removal performance of anammox consortia after nitrite inhibition. The findings provide a novel strategy and direction for improving the tolerance and resilience of anammox consortia in engineered ecosystems. © 2025

关键词： Listeria

来源：评论

学校读者我要写书评

暂无评论

Regional validity of the parameters of a distributed runoff-erosion model in the semi-arid region of Brazil

引用

Science China(Technological Sciences) 2009年第11期52卷 3348-3356页

作者： SRINIVASAN Vajapeyam Srirangachar PAIVA Fernanda Maria de Lima Federal University of Campina Grande Post-graduate programme in Civil and Environmental Engineering Campus I 58429-900 Campina Grande PB Brazil

The present paper examines the validity of the application of a distributed rainfall-runoff-erosion model on a regional basis in a semi-arid region of Brazil. The model tested is known as WESP (Water Erosion Simulation program) developed by Lopes (1987). The model simulates the hydrograph and the sediment graph for individual events and thus, the model when properly calibrated can serve as a predictive tool for runoff and soil erosion on an individual or a continuous basis. The possibility of the existence of regionally applicable values for the parameters of the model WESP would be very interesting from the point of view of predictability of runoff and soil erosion from ungauged basins in the region. For this purpose, data collected in several experimental units in the experimental basin of Sumé as well as in the experimental basin of So Joo de Cariri have been used. The model was calibrated and validated in each of the experimental units (consisting of erosion plots and micro-basins) and the average value from all of the units for each of the parameters was considered to be the regional value. With these average values, all the events in all the experimental units were simulated. The results show that the runoff and erosion values simulated with this single parameter set were very good in all the units, being well within the acceptable deviations.

关键词： regional parameters model WESP experimental basins semi-arid region soil erosion

来源：评论

学校读者我要写书评

暂无评论

Flow through side-combined structure in a channel bend under subcritical flow regime

引用

ISH Journal of Hydraulic engineering 2022年第2期28卷 203-211页

作者： Ghodsian, Masoud Feyzollahi, Farshid Ghodsian, Mohammad Faculty of Civil and Environmental Engineering and Water Engineering Research Institute Tarbiat Modares University Tehran Iran Ex. Post Graduate Student Department of Civil and Environmental Engineering Tarbiat Modares University Tehran Iran Ex. Post Graduate Student School of Management Economics and Progress Engineering Iran University of Science and Technology Tehran Iran

In this paper, the effects of the nondimensional parameters influencing the discharge coefficient of a side-combined structure located in a channel bend were studied using 288 experimental data. Experiments were conducted in a rectangular recirculating U-shaped channel (0.6 m width and 0.7 m height) for different discharges and depths of flow in the channel. The effects of approach Froude number Fr, the ratio of the gate height to gate opening d/a, the ratio of the approach flow depth to gate opening h 1/a, and angle of the bend curvature α on the discharge coefficient under subcritical flow conditions are investigated. It was found that the flow diversion by a side-combined structure leads to a reverse flow, two separation zones, and a stagnation zone in the main channel. The specific energy remains constant along with the side-combined structure. It was found that the discharge coefficient is a decreasing function of Fr and d/a. Moreover, the discharge coefficient increases by increasing h 1/a. By changing the location of the side-combined structure along the channel bend, the discharge coefficient reduces from upstream, reach to a minimum value at α= 90ᵒ, and increase further downstream. The discharge coefficient of a side-combined structure is maximums when it is located at section 115° of the bend. New equations for the discharge coefficient of a side-combined structure under subcritical flow conditions were obtained. © 2020 Indian Society for Hydraulics.

关键词： Hydraulics

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：