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The presence and distribution of antibiotics and antibiotic resistance genes (ARGs) in rivers have attracted significant global concern. However, research on the contamination of typical rivers in Sichuan Province, China, remains limited. This study aimed to assess the residual levels of antibiotics across 42 national and provincial monitoring sites in nine rivers within Sichuan using UPLC-MS/MS. Ecological risk levels were evaluated through established risk assessment methods, and antibiotic resistance in Escherichia coli(E.coli) isolated from these waters was determined using the Kirby-Bauer disk diffusion method. Additionally, redundancy analysis (RDA) was conducted to explore the impact of residual antibiotics on the microbial community structure in the Minjiang River basin. Antibiotics were detected in all nine rivers studied, with the Minjiang, Tuojiang, and Jialingjiang rivers exhibiting particularly severe contamination, with concentrations ranging from 0.29 to 2233.71 ng/L. The level of antibiotic pollution in the Sichuan Basin was significantly higher than in other regions of Sichuan, likely due to the area's high population density. Furthermore, 9.77% of E. coli isolates from the nine rivers exhibited antibiotic resistance, with over 5.8% demonstrating multidrugs resistance. Norfloxacin, amoxicillin, ampicillin, and tetracycline were identified as the primary contributors to the high ecological risk at 26 of the 42 monitoring sites. A strong correlation was observed between residual antibiotics and changes in microbial community structure. These findings provide critical insights into the distribution of antibiotics and ARGs in the rivers of Sichuan Province and highlight the urgent need for targeted strategies to mitigate antibiotic pollution. Addressing this issue is essential to protect both ecological integrity and public health. [ABSTRACT FROM AUTHOR]

Building energy consumption management significantly impacts energy efficiency, environmental effects, and economic benefits throughout a building's life cycle. Optimizing building energy consumption has become a great challenge in the field of green buildings. This paper proposes an automated simulation method that integrates the EnergyPlus energy consumption simulation tool with Python scripting. This approach efficiently generates large volumes of energy consumption data and supports the development of machine learning surrogate models, thereby enhancing simulation efficiency and reducing computational costs. Based on this foundation, the multi-objective optimization algorithm NSGA-III is introduced to achieve a balanced optimization of three primary objectives: building energy consumption, photovoltaic electricity generation, and thermal comfort. Through a systematic analysis of a case study involving an office building and dormitory at a construction site in China, the effects of building envelope, air conditioning systems, and occupant behavior on energy consumption are examined. The optimization results indicate that energy consumption is reduced by 41% for the office building and 38% for the dormitory. Additionally, photovoltaic electricity generation increases by 176% and 169% compared to the baseline model, while thermal comfort improves by 19% and 6%, respectively. These improvements significantly enhance energy self-sufficiency and residential comfort. [ABSTRACT FROM AUTHOR]

The damage of expansion joints is a common problem of bridges, which adversely affects not only driving comfort and safety but also the durability of the structure. Jointless bridges can fundamentally solve this fragile problem. However, how to accurately assess its environmental and economic benefits has not been studied, specifically as climate change intensifies. To address these issues, this study first examines the effects of climate change on design expansion allowance of bridge expansion joints based on climate projections. Subsequently, the life-cycle environmental and economic benefits of two jointless bridges located in Beijing–Hong Kong–Macau Expressway are quantified under climate change scenarios. Moreover, uncertainty and random forest algorithm-based importance analyses are carried out to help decision-makers identify major environmental and economic factors and develop eco-friendly plans to facilitate jointless bridge construction. Results indicate the following: (1) the design expansion allowance of bridge expansion joints tends to increase with the time-dependent temperature and humidity; (2) the avoidance of traffic detours caused by the maintenance and replacement of expansion joints is a major source of life-cycle environmental and economic benefits; (3) traffic detour distance is the most important factor influencing the life-cycle environmental and economic benefits. [ABSTRACT FROM AUTHOR]

The synthesis of adipic acid, which is formed by the reaction of cyclohexene oxidized by hydrogen peroxide (H2O2), is hazardous because of the highly exothermic nature of this reaction and H2O2 decomposition. The objective of this comprehensive study was to investigate and illustrate the effects of sulfuric acid (H2SO4) and H2O2 stabilizer (EDTA) on the thermal hazard of H2O2 decomposition and the green synthesis of adipic acid, which also provided a reference to reduce the risk of the reactions. Various calorimetry techniques were carried out to characterize the exothermic behavior of the reactions. An HPLC device was used to characterize the yield of adipic acid and the conversion rate of the raw materials, cyclohexene and H2O2. Meanwhile, density functional theory calculations were performed to understand the reaction mechanism and the associated energies of H2O2 decomposition catalyzed by sodium tungstate dihydrate (Na2WO4·2H2O). Finally, combined with the calorimetry results, the risk of the adipic acid synthesis reaction was assessed using the intrinsic control index method (ITHI). The results show that the addition of H2SO4 and EDTA can reduce the exothermic heat of the H2O2 decomposition reaction and the green synthesis reaction of adipic acid. The yield of adipic acid was also increased. The hazard level of stage A was IV, and to remove more reaction heat, it was recommended to enhance the reflux cooling of stage A. The hazard level of stage B was I, which was very low and no further measures could be taken. [ABSTRACT FROM AUTHOR]

Increased temperature and carbon dioxide concentration caused by climate change will aggravate the creep shrinkage and structural durability of concrete bridges. Overloading also has a great impact on the time-dependent reliability of existing bridges. This research paper analyses the time-dependent reliability of bridges based on climate change and overload. By improving the concrete carbonation model and referring to the B4 model of concrete creep, the effects of ambient temperature and humidity on concrete under different emission-reduction scenarios were considered. At the same time, given the serious problems of vehicle overload in China, combining different overload scenarios with climate change led to the establishment of a time-dependent reliability model for precast-concrete bridges. The results showed that as the overload rate increased, the time-dependent reliability degradation rate of a case study bridge accelerated. Under the scenario considering both high greenhouse gas emissions and the maximum overload rate, the service life of the case study bridge decreased to 50% of its design life. [ABSTRACT FROM AUTHOR]

China has many bridges in a vulnerable condition, and strengthening is crucial to guarantee their service life and performance. However, environmental impact is rarely considered in the maintenance of reinforced concrete structures. Moreover, considering the effects of vehicle overload and the external environment remains difficult. To solve these problems, the life-cycle reliability and induced environmental impact of strengthening bridges with bonded carbon-fibre-reinforced polymer under different external environmental conditions and overload scenarios were studied using Monte Carlo sampling, first-order second moment and life-cycle assessment methods. A simply supported reinforced concrete T-beam was selected as a case study. The results indicated that the external environmental conditions contributed significantly to the polymer strengthening effect, and polymer plates contributed more to reliability than polymer fabric. In overload scenarios, plates were more suitable for strengthening than fabric. When annual environmental impacts were considered over time, life-cycle maintenance plans with plates were better than with fabric, and environmental impacts were sensitive to the discount rate. [ABSTRACT FROM AUTHOR]

With the development of civil engineering sustainability, the scope of corresponding research covers a broader range. It is difficult for researchers to master the holistic situation of the study, leading to duplication and lag of their research. Therefore, this paper aims to present a state-of-the-art of the research of civil engineering sustainability by adopting two new methods (bibliometric and social network analysis) to review the literature of this field. It is concluded that the existing research takes engineering as the main subject to improve its sustainability through technologies. Current research mainly focuses on technological innovations and evaluations of environmental impacts in the fields of construction technology, energy consumption, material preparation, and design. The countries with the largest number of published articles are the United States and China. The Hong Kong Polytechnic University is the institution that has published more articles than others. Journal of Cleaner Production and Sustainability are the journals that have published the most articles. For the researchers, a professor of the University of Adelaide is the researcher who has published the most articles, and experts from South China University of Technology, Chongqing University, and University of Brighton are the main hubs among different researchers. [ABSTRACT FROM AUTHOR]

Energy consumption and pollutant emissions from buildings have caused serious impacts on the environment. Currently, research on building environmental costs is quite insufficient. Based on life cycle inventory of building materials, fossil fuel and electricity power, a calculating model for environmental costs during different stages is presented. A single-objective optimization model is generated by converting environmental impact into environmental cost, with the same unit with direct cost. Two residential buildings, one located in Beijing and another in Xiamen, China, are taken as the case studies and analyzed to test the proposed model. Moreover, data uncertainty and sensitivity analysis of key parameters, including the discount rate and the unit virtual abatement costs of pollutants, are also conducted. The analysis results show that the environmental cost accounts for about 16% of direct cost. The environmental degradation cost accounts for about 70% of the total environmental cost. According to the probabilistic uncertainty analysis results, the coefficient of variation of material production stage is the largest. The sensitivity analysis results indicate that the unit virtual abatement cost of CO2 has the largest influence on the final environmental cost. [ABSTRACT FROM AUTHOR]