The decarbonization of urban water systems is critical for achieving global climate goals,and reducing the carbon intensity of urban water systems necessitates a paradigm shift from traditional end-of-pipe treatment a...The decarbonization of urban water systems is critical for achieving global climate goals,and reducing the carbon intensity of urban water systems necessitates a paradigm shift from traditional end-of-pipe treatment approaches to alternative technological solutions and holistic planning.This study explores a comprehensive strategy for achieving sustainable urban water management that integrates a decentral-ized water system(DWS),source separation,and low-carbon water treatment technologies.DWS is fun-damental to implementing a sustainable urban water system.This study addresses the social contexts,costs,approaches,and benefits associated with DWS implementation,emphasizing the importance of its construction.Subsequently,the analysis focuses on the on-site source separation of grey water,feces,and yellow water in the DWS,which serves as the primary approach for wastewater reuse and N/P recov-ery for a sustainable urban water system.Following source separation,low-carbon water treatment tech-nologies based on resource conservation and recovery are thoroughly discussed.Specifically,resource conservation can be achieved through rainwater control,efficiency improvements,and low energy con-sumption,while resource recovery can be attained through carbon capturing and energy/nutrient recov-ery.Overall,in response to the challenges in current urban water management,this study proposes a comprehensive strategy that supports a sustainable urban water system,providing theoretical guidance for reducing carbon emissions.展开更多
Engineered water systems such as wastewater treatment plants(WWTPs)are potential reservoirs of various biological risk factors(BRFs),including pathogens,antibiotic resistance genes(ARGs),and virulence factors(VFs).Cur...Engineered water systems such as wastewater treatment plants(WWTPs)are potential reservoirs of various biological risk factors(BRFs),including pathogens,antibiotic resistance genes(ARGs),and virulence factors(VFs).Currently,a BRF database relevant to engineered water systems on a global geographic scale is lacking.Here,we present the Global Wastewater Pathogen Database(GWPD),an online database that provides information on the diversity,abundance,and distribution of BRFs from 1302 metagenome samples obtained from 186 cities,68 countries,and six continents.We sorted these samples into six types:sewer networks,influent,anoxic activated sludge,oxic activated sludge,effluent,and receiving/natural waters.In total,476 pathogens,442 ARGs,and 246 VFs were identified.As a multifunctional database,GWPD provides an interactive visualization of these BRFs in a world map,an information retrieval interface,and an online one-click service for BRF annotation from metagenome sequencing data.GWPD is built on a web service framework,which can be readily extended to future versions of GWPD by adding more functional modules and connecting to other data sources,such as epidemic databases,to support risk assessment and control in the context of“One Health.”展开更多
Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain ...Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain underexplored.This study aims to establish a multidimensional ecological safety evaluation framework for reclaimed water replenishment systems and propose hierarchical risk prevention strategies.By integrating ecotoxicological assays(algae growth inhibition,Daphnia behavioral anomalies,zebrafish embryo toxicity),multimedia exposure modeling,and Monte Carlo probabilistic simulations,the risk contributions and spatial heterogeneity of typical pollutants are quantitatively analyzed.Results revealed that sulfamethoxazole(RQ=2.3)and diclofenac(RQ=1.8)posed high ecological risks,with their effects nonlinearly correlated with hydraulic retention time(HRT<3 days)and nutrient loading(TN>1.2 mg/L).A three-tier risk prevention system was developed based on the“source-pathway-receptor”framework:ozone-activated carbon pretreatment achieved 85%removal efficiency for pharmaceutical contaminants,ecological floating beds enhanced nitrogen and phosphorus retention by 40%-60%,and hydraulic regulation(flow velocity>0.1 m/s)effectively suppressed pathogen proliferation.The innovation of this study lies in establishing a chemical-biological-hydrological coupled risk quantification model for reclaimed water reuse scenarios.The hierarchical prevention standards have been incorporated into local reclaimed water management regulations,providing a scientific foundation and technical paradigm for sustainable landscape water replenishment.展开更多
[Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchi...[Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchicine injection method in vivo,the morphological characteristics and karyotype of P.fulvidraco in Yuanshui River and Lishui River of Dongting Lake were analyzed.[Result] In three ratio traits including standard length/head length,standard length/caudal peduncle depth,head length/snout length,P.fulvidraco of Yuanshui River and Lishui River had significant differences（P0.05）.However,the number and karyotype of their chromosomes were same.The chromosome number was 2n = 52,and the karyotype formula was 20M＋12SM＋10ST＋10T.The number of chromosome arm was 84.[Conclusion] The research result had certain theoretical guidance significance for the protection and utilization of wild P.resource in Dongting Lake water system.展开更多
Hydraulic control valves, positioned at the terminus of pipe networks, are critical for regulatingflow and pressure, thereby ensuring the operational safety and efficiency of pipeline systems. However,conventional val...Hydraulic control valves, positioned at the terminus of pipe networks, are critical for regulatingflow and pressure, thereby ensuring the operational safety and efficiency of pipeline systems. However,conventional valve designs often struggle to maintain effective regulation across a wide range of systempressures. To address this limitation, this study introduces a novel Pilot hydraulic valves specificallyengineered for enhanced dynamic performance and precise regulation under variable pressure conditions.Building upon prior experimental findings, the proposed design integrates a high-fidelity simulationframework and a surrogate model-based optimization strategy. The study begins by formulating acomprehensive mathematical model of the pipeline system using electro-hydraulic simulation techniques,capturing the dynamic behavior of both the pilot valve and the broader urban water distribution network. Acoupled simulation platform is then developed, leveraging both one-dimensional (1D) and three-dimensional(3D) software tools to accurately analyze the valve’s transient response and operational characteristics. Toachieve optimal valve performance, a multi-objective optimization approach is proposed. This approachemploys a Levy-based Improved Tuna-InspiredWake-Up Optimization Algorithm (L-TIWOA) to refine aBackpropagation (BP) neural network, thereby constructing a highly accurate surrogate model. Compared tothe conventional BP neural network, the improved model demonstrates significantly reduced mean absoluteerror (MAE) and mean squared error (MSE), underscoring its superior predictive capability. The surrogatemodel serves as the objective function within an Improved Multi-Objective Mother Lode OptimizationAlgorithm (IMOMLOA), which is then used to fine-tune the key design parameters of the control valve.Validation through experimental testing reveals that the optimized valve achieves a maximum flow deviationof just 1.11 t/h, corresponding to a control accuracy of 3.7%, at a target flow rate of 30 t/h. Moreover,substantial improvements in dynamic response are observed, confirming the effectiveness of the proposeddesign and optimization strategy.展开更多
With a view to treating the nitrate pollution in water systems,this article presents a novel method for eliminating nitrate from wastewater by bacteria through unsaturated zone. First,highly efficient denitrifiers sui...With a view to treating the nitrate pollution in water systems,this article presents a novel method for eliminating nitrate from wastewater by bacteria through unsaturated zone. First,highly efficient denitrifiers suitable for underground environment have been studied based on the biochemical characterization and denitrifying mechanism of microorganisms. Then the nitrate-eliminating modeling study in soil columns was carried out with the obtained denitrifier. The results show that the nitrate-eeliminating efficiency can reach 98%,so it has practical value in controlling nitrate pollution in water systems.展开更多
Central air-conditioning system in building includes chiller, water system, air duct system, control system, etc. Among the energy consumption, building energy consumption accounts for a large proportion, and the ener...Central air-conditioning system in building includes chiller, water system, air duct system, control system, etc. Among the energy consumption, building energy consumption accounts for a large proportion, and the energy consumption of air-conditioning system is the main energy consumption source of the whole system. In the scheme design of central air conditioning system, the local load characteristics are usually considered, and the design method of high ratio is adopted. The results show that the building air-conditioning system rarely works under full load condition, mostly under 75% load condition, so it needs to be continuously optimized. Therefore, in order to reduce the energy consumption of central air-conditioning, we must optimize the energy-saving technology of central air-conditioning water system.展开更多
Recent research on deterministic methods for circulating cooling water systems optimization has been well developed. However, the actual operating conditions of the system are mostly variable, so the system obtained u...Recent research on deterministic methods for circulating cooling water systems optimization has been well developed. However, the actual operating conditions of the system are mostly variable, so the system obtained under deterministic conditions may not be stable and economical. This paper studies the optimization of circulating cooling water systems under uncertain circumstance. To improve the reliability of the system and reduce the water and energy consumption, the influence of different uncertain parameters is taken into consideration. The chance constrained programming method is used to build a model under uncertain conditions, where the confidence level indicates the degree of constraint violation. Probability distribution functions are used to describe the form of uncertain parameters. The objective is to minimize the total cost and obtain the optimal cooling network configuration simultaneously.An algorithm based on Monte Carlo method is proposed, and GAMS software is used to solve the mixed integer nonlinear programming model. A case is optimized to verify the validity of the model. Compared with the deterministic optimization method, the results show that when considering the different types of uncertain parameters, a system with better economy and reliability can be obtained(total cost can be reduced at least 2%).展开更多
Method for constructing the optimal water supply line and formulas for calculating the targets for single-contaminant regeneration recycling water systems are improved to apply to the situation of variational pararnet...Method for constructing the optimal water supply line and formulas for calculating the targets for single-contaminant regeneration recycling water systems are improved to apply to the situation of variational pararneters in this article. Based on these extending methods, the effect of varying freshwater consumption and regenerated water flow rate on the optimizing results are investigated. The interactions of parameters of regeneration recycling systems are summarized. Finally, all the conclusions are illustrated from the results of mathematical programming through an example.展开更多
With the growth of intermittent renewable energy generation in power grids,there is an increasing demand for controllable resources to be deployed to guarantee power quality and frequency stability.The flexibility of ...With the growth of intermittent renewable energy generation in power grids,there is an increasing demand for controllable resources to be deployed to guarantee power quality and frequency stability.The flexibility of demand response(DR)resources has become a valuable solution to this problem.However,existing research indicates that problems on flexibility prediction of DR resources have not been investigated.This study applied the temporal convolution network(TCN)-combined transformer,a deep learning technique to predict the aggregated flexibility of two types of DR resources,that is,electric vehicles(EVs)and domestic hot water system(DHWS).The prediction uses historical power consumption data of these DR resources and DR signals(DSs)to facilitate prediction.The prediction can generate the size and maintenance time of the aggregated flexibility.The accuracy of the flexibility prediction results was verified through simulations of case studies.The simulation results show that under different maintenance times,the size of the flexibility changed.The proposed DR resource flexibility prediction method demonstrates its application in unlocking the demand-side flexibility to provide a reserve to grids.展开更多
Yangzhou Slender West Lake is narrow in shape. It is 4.3 km in total length with the width of about 100 m. It is a typical zonal water system. Through the research of its spatial structure, space sequence and view bor...Yangzhou Slender West Lake is narrow in shape. It is 4.3 km in total length with the width of about 100 m. It is a typical zonal water system. Through the research of its spatial structure, space sequence and view borrowing the garden bridges of Yangzhou Slender West Lake, the unique gardening method of zonal water system was expatiated.展开更多
Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optim...Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization.展开更多
Objective Our objective was to investigate the occurrence of opportunistic pathogens and characterize the bacterial community structures in the water system of a pulmonary hospital.Methods The water samples were colle...Objective Our objective was to investigate the occurrence of opportunistic pathogens and characterize the bacterial community structures in the water system of a pulmonary hospital.Methods The water samples were collected from automatic and manual faucets in the consulting room,treatment room,dressing room,respiratory ward,and other non-medical rooms in three buildings of the hospital.Quantitative polymerase chain reaction was used to quantify the load of several waterborne opportunistic pathogens and related microorganisms,including Legionella spp.,Mycobacterium spp.,and M.avium.Illumina sequencing targeting 16 S r RNA genes was performed to profile bacterial communities.Results The occurrence rates of Legionella spp.,Mycobacterium spp.,and M.avium were 100%,100%,and 76%,respectively in all samples.Higher occurrence rates of M.avium were observed in the outpatient service building(building 1,91.7%)and respiration department and wards(building 2,80%)than in the office building(building 3),where no M.avium was found.M.avium were more abundant in automatic faucets(average 2.21×10~4 gene copies/L)than in manual faucets(average 1.03×10~4 gene copies/m L)(P<0.01).Proteobacteria,Actinobacteria,Bacteroidetes,Cyanobacteria,Firmicutes,and Acidobacteria were the dominant bacterial phyla.Disinfectant residuals,nitrate,and temperature were found to be the key environmental factors driving microbial community structure shifts in water systems.Conclusion This study revealed a high level of colonization of water faucets by opportunistic pathogens and provided insight into the characteristics of microbial communities in a hospital water system and approaches to reduce risks of microbial contamination.展开更多
In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equat...In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equations is established. Some sufficient conditions for blow-up of the solutions in finite time are given. Moreover, by separation method, the self-similar solutions for the nonlinear shallow water equations are obtained, and which local or global behavior can be determined by the corresponding Emden equation.展开更多
To manage potential microbial risks and meet increasingly strict drinking water health standards,UV treatment has attracted increasing attention for use in drinking water systems in China.However,the effects of UV tre...To manage potential microbial risks and meet increasingly strict drinking water health standards,UV treatment has attracted increasing attention for use in drinking water systems in China.However,the effects of UV treatment on microbial control and disinfection byproducts(DBPs)formation in real municipal drinking water systems are poorly understood.Here,we collected water samples from three real drinking water systems in Beijing and Tianjin to investigate the impacts of UV treatment on microbial control and DBP formation.We employed heterotrophic plate count(HPC),flow cytometry(FCM),quantitative PCR analysis,and high-throughput sequencing to measure microorganisms in the samples.Different trends were observed between HPC and total cell count(measured by FCM),indicating that a single indicator could not reflect the real degree of biological re-growth in drinking water distribution systems(DWDSs).A significant increase in the 16S rRNA gene concentration was observed when the UV system was stopped.Besides,the bacterial community composition was similar at the phylum level but differed markedly at the genera level among the three DWDSs.Some chlorine-resistant bacteria,including potential pathogens(e.g.,Acinetobacter)showed a high relative abundance when the UV system was turned off.It can be concluded that UV treatment can mitigate microbial re-growth to some extent.Finally,UV treatment had a limited influence on the formation of DBPs,including trihalomethanes,haloacetic acids,and nitrogenated DBPs.The findings of this study may help to understand the performance of UV treatment in real drinking water systems.展开更多
A combined process was developed to inhibit the corrosion both in the pipeline of reclaimed water supplies（PRWS） and in downstream recirculating cooling water systems（RCWS）using the reclaimed water as makeup. Hydr...A combined process was developed to inhibit the corrosion both in the pipeline of reclaimed water supplies（PRWS） and in downstream recirculating cooling water systems（RCWS）using the reclaimed water as makeup. Hydroxyl carboxylate-based corrosion inhibitors（e.g.,gluconate, citrate, tartrate） and zinc sulfate heptahydrate, which provided Zn^2＋ as a synergistic corrosion inhibition additive, were added prior to the PRWS when the phosphate（which could be utilized as a corrosion inhibitor） content in the reclaimed water was below 1.7 mg/L, and no additional corrosion inhibitors were required for the downstream RCWS.Satisfactory corrosion inhibition was achieved even if the RCWS was operated under the condition of high numbers of concentration cycles. The corrosion inhibition requirement was also met by the appropriate combination of PO4^3- and Zn^2＋ when the phosphate content in the reclaimed water was more than 1.7 mg/L. The process integrated not only water reclamation and reuse, and the operation of a highly concentrated RCWS, but also the comprehensive utilization of phosphate in reclaimed water and the application of non-phosphorus corrosion inhibitors. The proposed process reduced the operating cost of the PRWS and the RCWS, and lowered the environmental hazard caused by the excessive discharge of phosphate. Furthermore, larger amounts of water resources could be conserved as a result.展开更多
The energy saving issue of chilled water system in an intelligent building is analyzed from the systematic point of view, and an optimum scheduling scheme which can save energy of the system facilities and satisfy the...The energy saving issue of chilled water system in an intelligent building is analyzed from the systematic point of view, and an optimum scheduling scheme which can save energy of the system facilities and satisfy the constraints of the real time cold loads and system running is also proposed. It can make the minimum cost of the system by optimizing the number of running chillers, running parameters and the distribution of real time loads of running chillers. The improved genetic algorithm is used in the optimum scheduling scheme. The computation results show that the building energy consumption can be decreased by about 10%.展开更多
An integrative technology including the surfactant enhanced sorption and subsequentdesorption and biodegradation of phenanthrene in the soil-water system was introduced and tested. For slightly contaminated agricultur...An integrative technology including the surfactant enhanced sorption and subsequentdesorption and biodegradation of phenanthrene in the soil-water system was introduced and tested. For slightly contaminated agricultural soils, cationic-nonionic mixed surfactant- enhanced sorption of organic contaminants onto soils could reduce their transfer to plants, therefore safe-guarding agricultural production. After planting, residual surfactants combined with added nonionic surfactant could also promote thedesorption and biodegradation of residual phenanthrene, thus providing a cost-effective pollution remediation technology.0ur results showed that the cationic-nonionic mixed surfactantsdodecylpyridinium bromide （DDPB） and Triton X-100 （TX100） significantly enhanced soil retention of phenanthrene. The maximum sorption coefficient Kd＊ of phenanthrene for contaminated soils treated by mixed surfactants was about24.5 times that of soils without surfactant （Kd ） and higher than the combined effects of DDPB and TX100 individually, which was about 16.7 and 1.5 times Kd , respectively.0n the other hand, TX100 could effectively remove phenanthrene from contaminated soils treated by mixed surfactants, improving the bioavailability of organic pollutants. Thedesorption rates of phenanthrene from these treated soils were greater than 85% with TX100 concentration above2000 mg/L and approached 100% with increasing TX100 concentration. The biodegradation rates of phenanthrene in the presence of surfactants reached over 95% in30days. The mixed surfactants promoted the biodegradation of phenanthrene to some extent in 10-22days, and had no obvious impact on phenanthrene biodegradation at the end of the experiment. Results obtained from this study provide some insight for the production of safe agricultural products and a remediation scheme for soils slightly contaminated with organic pollutants.展开更多
Demand response(DR)is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation.Changes in electricity markets regulation in several...Demand response(DR)is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation.Changes in electricity markets regulation in several countries have recently enabled an effective integration of DR mechanisms in power systems.Through its flexible components(pumps,tanks),drinking water systems are suitable candidates for energy-efficient DR mechanisms.However,these systems are often managed independently of power system operation for both economic and operational reasons.Indeed,a sufficient level of economic viability and water demands risk management are necessary for water utilities to integrate their flexibilities to power system operation.In this paper,we proposed a mathematical model for optimizing pump schedules in water systems while trading DR blocs in a spot power market during peak times.Uncertainties about water demands were considered in the mathematical model allowing to propose power reductions covering the potential risk of real-time water demand forecasting inaccuracy.Numerical results were discussed on a real water system in France,demonstrating both economic and ecological benefits.展开更多
In this article VLE data for a ternary system (propylene-methanol-water) under 30～60 C,0. 3～0. 9 MPa with a mass ratio of methanol to water of 9:1, 8: 2, 7: 3 were determined with a static equilibrium still, and wer...In this article VLE data for a ternary system (propylene-methanol-water) under 30～60 C,0. 3～0. 9 MPa with a mass ratio of methanol to water of 9:1, 8: 2, 7: 3 were determined with a static equilibrium still, and were correlated by using Peng-Robinson model. The average relative error ofpropylene concentration in liquid phase is 1. 46 %. The results indicate that the models are very suitablefor the ternary system and the data are reliable.展开更多
基金supported by the National Natural Science Foun-dation of China(52200008 and 52270043)the Young Elite Scien-tists Sponsorship Program by CAST,National Key Research and Developing Program of China(2023YFE0113800)+1 种基金the China Post-doctoral Science Foundation(2022M710034)the Chengde National Sustainable Development Agenda Innovation Demonstra-tion Zone Construction Technology Special Project(202202F003).
文摘The decarbonization of urban water systems is critical for achieving global climate goals,and reducing the carbon intensity of urban water systems necessitates a paradigm shift from traditional end-of-pipe treatment approaches to alternative technological solutions and holistic planning.This study explores a comprehensive strategy for achieving sustainable urban water management that integrates a decentral-ized water system(DWS),source separation,and low-carbon water treatment technologies.DWS is fun-damental to implementing a sustainable urban water system.This study addresses the social contexts,costs,approaches,and benefits associated with DWS implementation,emphasizing the importance of its construction.Subsequently,the analysis focuses on the on-site source separation of grey water,feces,and yellow water in the DWS,which serves as the primary approach for wastewater reuse and N/P recov-ery for a sustainable urban water system.Following source separation,low-carbon water treatment tech-nologies based on resource conservation and recovery are thoroughly discussed.Specifically,resource conservation can be achieved through rainwater control,efficiency improvements,and low energy con-sumption,while resource recovery can be attained through carbon capturing and energy/nutrient recov-ery.Overall,in response to the challenges in current urban water management,this study proposes a comprehensive strategy that supports a sustainable urban water system,providing theoretical guidance for reducing carbon emissions.
基金supported by the National Natural Science Foundation of China(52321005,52293441,52293443,52230004)the Shenzhen Stability Support Key Program in Colleges and Universities of China(GXWD20231127195344001)+3 种基金the Natural Science Foundation of Guangdong Basic and Applied Basic Research Foundation(2024A1515010085)the Shenzhen Overseas High-level Talents Research Startup Program(20200518750C)the Shenzhen Science and Technology Program(KQTD20190929172630447)the Open Project of the Key Laboratory of Environmental Biotechnology,CAS(KF2021006).
文摘Engineered water systems such as wastewater treatment plants(WWTPs)are potential reservoirs of various biological risk factors(BRFs),including pathogens,antibiotic resistance genes(ARGs),and virulence factors(VFs).Currently,a BRF database relevant to engineered water systems on a global geographic scale is lacking.Here,we present the Global Wastewater Pathogen Database(GWPD),an online database that provides information on the diversity,abundance,and distribution of BRFs from 1302 metagenome samples obtained from 186 cities,68 countries,and six continents.We sorted these samples into six types:sewer networks,influent,anoxic activated sludge,oxic activated sludge,effluent,and receiving/natural waters.In total,476 pathogens,442 ARGs,and 246 VFs were identified.As a multifunctional database,GWPD provides an interactive visualization of these BRFs in a world map,an information retrieval interface,and an online one-click service for BRF annotation from metagenome sequencing data.GWPD is built on a web service framework,which can be readily extended to future versions of GWPD by adding more functional modules and connecting to other data sources,such as epidemic databases,to support risk assessment and control in the context of“One Health.”
文摘Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain underexplored.This study aims to establish a multidimensional ecological safety evaluation framework for reclaimed water replenishment systems and propose hierarchical risk prevention strategies.By integrating ecotoxicological assays(algae growth inhibition,Daphnia behavioral anomalies,zebrafish embryo toxicity),multimedia exposure modeling,and Monte Carlo probabilistic simulations,the risk contributions and spatial heterogeneity of typical pollutants are quantitatively analyzed.Results revealed that sulfamethoxazole(RQ=2.3)and diclofenac(RQ=1.8)posed high ecological risks,with their effects nonlinearly correlated with hydraulic retention time(HRT<3 days)and nutrient loading(TN>1.2 mg/L).A three-tier risk prevention system was developed based on the“source-pathway-receptor”framework:ozone-activated carbon pretreatment achieved 85%removal efficiency for pharmaceutical contaminants,ecological floating beds enhanced nitrogen and phosphorus retention by 40%-60%,and hydraulic regulation(flow velocity>0.1 m/s)effectively suppressed pathogen proliferation.The innovation of this study lies in establishing a chemical-biological-hydrological coupled risk quantification model for reclaimed water reuse scenarios.The hierarchical prevention standards have been incorporated into local reclaimed water management regulations,providing a scientific foundation and technical paradigm for sustainable landscape water replenishment.
基金Supported by National Natural Science Foundation of China(30972260)Science and Technology Innovation Team Plan of Hunan Higher Education(2010)~~
文摘[Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchicine injection method in vivo,the morphological characteristics and karyotype of P.fulvidraco in Yuanshui River and Lishui River of Dongting Lake were analyzed.[Result] In three ratio traits including standard length/head length,standard length/caudal peduncle depth,head length/snout length,P.fulvidraco of Yuanshui River and Lishui River had significant differences（P0.05）.However,the number and karyotype of their chromosomes were same.The chromosome number was 2n = 52,and the karyotype formula was 20M＋12SM＋10ST＋10T.The number of chromosome arm was 84.[Conclusion] The research result had certain theoretical guidance significance for the protection and utilization of wild P.resource in Dongting Lake water system.
基金Gansu Provincial Department of Education(Industrial Support Plan Project:202CYZC-048).
文摘Hydraulic control valves, positioned at the terminus of pipe networks, are critical for regulatingflow and pressure, thereby ensuring the operational safety and efficiency of pipeline systems. However,conventional valve designs often struggle to maintain effective regulation across a wide range of systempressures. To address this limitation, this study introduces a novel Pilot hydraulic valves specificallyengineered for enhanced dynamic performance and precise regulation under variable pressure conditions.Building upon prior experimental findings, the proposed design integrates a high-fidelity simulationframework and a surrogate model-based optimization strategy. The study begins by formulating acomprehensive mathematical model of the pipeline system using electro-hydraulic simulation techniques,capturing the dynamic behavior of both the pilot valve and the broader urban water distribution network. Acoupled simulation platform is then developed, leveraging both one-dimensional (1D) and three-dimensional(3D) software tools to accurately analyze the valve’s transient response and operational characteristics. Toachieve optimal valve performance, a multi-objective optimization approach is proposed. This approachemploys a Levy-based Improved Tuna-InspiredWake-Up Optimization Algorithm (L-TIWOA) to refine aBackpropagation (BP) neural network, thereby constructing a highly accurate surrogate model. Compared tothe conventional BP neural network, the improved model demonstrates significantly reduced mean absoluteerror (MAE) and mean squared error (MSE), underscoring its superior predictive capability. The surrogatemodel serves as the objective function within an Improved Multi-Objective Mother Lode OptimizationAlgorithm (IMOMLOA), which is then used to fine-tune the key design parameters of the control valve.Validation through experimental testing reveals that the optimized valve achieves a maximum flow deviationof just 1.11 t/h, corresponding to a control accuracy of 3.7%, at a target flow rate of 30 t/h. Moreover,substantial improvements in dynamic response are observed, confirming the effectiveness of the proposeddesign and optimization strategy.
文摘With a view to treating the nitrate pollution in water systems,this article presents a novel method for eliminating nitrate from wastewater by bacteria through unsaturated zone. First,highly efficient denitrifiers suitable for underground environment have been studied based on the biochemical characterization and denitrifying mechanism of microorganisms. Then the nitrate-eliminating modeling study in soil columns was carried out with the obtained denitrifier. The results show that the nitrate-eeliminating efficiency can reach 98%,so it has practical value in controlling nitrate pollution in water systems.
文摘Central air-conditioning system in building includes chiller, water system, air duct system, control system, etc. Among the energy consumption, building energy consumption accounts for a large proportion, and the energy consumption of air-conditioning system is the main energy consumption source of the whole system. In the scheme design of central air conditioning system, the local load characteristics are usually considered, and the design method of high ratio is adopted. The results show that the building air-conditioning system rarely works under full load condition, mostly under 75% load condition, so it needs to be continuously optimized. Therefore, in order to reduce the energy consumption of central air-conditioning, we must optimize the energy-saving technology of central air-conditioning water system.
基金Financial support from the National Natural Science Foundation of China (22022816, 22078358)。
文摘Recent research on deterministic methods for circulating cooling water systems optimization has been well developed. However, the actual operating conditions of the system are mostly variable, so the system obtained under deterministic conditions may not be stable and economical. This paper studies the optimization of circulating cooling water systems under uncertain circumstance. To improve the reliability of the system and reduce the water and energy consumption, the influence of different uncertain parameters is taken into consideration. The chance constrained programming method is used to build a model under uncertain conditions, where the confidence level indicates the degree of constraint violation. Probability distribution functions are used to describe the form of uncertain parameters. The objective is to minimize the total cost and obtain the optimal cooling network configuration simultaneously.An algorithm based on Monte Carlo method is proposed, and GAMS software is used to solve the mixed integer nonlinear programming model. A case is optimized to verify the validity of the model. Compared with the deterministic optimization method, the results show that when considering the different types of uncertain parameters, a system with better economy and reliability can be obtained(total cost can be reduced at least 2%).
基金Supported by the National Natural Science Foundation of China （No.20436040）.
文摘Method for constructing the optimal water supply line and formulas for calculating the targets for single-contaminant regeneration recycling water systems are improved to apply to the situation of variational pararneters in this article. Based on these extending methods, the effect of varying freshwater consumption and regenerated water flow rate on the optimizing results are investigated. The interactions of parameters of regeneration recycling systems are summarized. Finally, all the conclusions are illustrated from the results of mathematical programming through an example.
基金This work was supported by the National Natural Science Foundation of China(51877078 and 52061635102)the Beijing Nova Program(Z201100006820106).
文摘With the growth of intermittent renewable energy generation in power grids,there is an increasing demand for controllable resources to be deployed to guarantee power quality and frequency stability.The flexibility of demand response(DR)resources has become a valuable solution to this problem.However,existing research indicates that problems on flexibility prediction of DR resources have not been investigated.This study applied the temporal convolution network(TCN)-combined transformer,a deep learning technique to predict the aggregated flexibility of two types of DR resources,that is,electric vehicles(EVs)and domestic hot water system(DHWS).The prediction uses historical power consumption data of these DR resources and DR signals(DSs)to facilitate prediction.The prediction can generate the size and maintenance time of the aggregated flexibility.The accuracy of the flexibility prediction results was verified through simulations of case studies.The simulation results show that under different maintenance times,the size of the flexibility changed.The proposed DR resource flexibility prediction method demonstrates its application in unlocking the demand-side flexibility to provide a reserve to grids.
文摘Yangzhou Slender West Lake is narrow in shape. It is 4.3 km in total length with the width of about 100 m. It is a typical zonal water system. Through the research of its spatial structure, space sequence and view borrowing the garden bridges of Yangzhou Slender West Lake, the unique gardening method of zonal water system was expatiated.
基金Financial support from the National Natural Science Foundation of China (22022816 and 22078358)
文摘Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization.
基金supported by the National Natural Science Foundation of China[No.51878468 and No.51508397]the Hospital Management Research Fund of Shanghai Medical Association[No.Q1902037]+1 种基金the Fundamental Research Funds for the Central Universitiesthe National Major Science and Technology Project for Water Pollution Control and Treatment[No.2017ZX07201002]。
文摘Objective Our objective was to investigate the occurrence of opportunistic pathogens and characterize the bacterial community structures in the water system of a pulmonary hospital.Methods The water samples were collected from automatic and manual faucets in the consulting room,treatment room,dressing room,respiratory ward,and other non-medical rooms in three buildings of the hospital.Quantitative polymerase chain reaction was used to quantify the load of several waterborne opportunistic pathogens and related microorganisms,including Legionella spp.,Mycobacterium spp.,and M.avium.Illumina sequencing targeting 16 S r RNA genes was performed to profile bacterial communities.Results The occurrence rates of Legionella spp.,Mycobacterium spp.,and M.avium were 100%,100%,and 76%,respectively in all samples.Higher occurrence rates of M.avium were observed in the outpatient service building(building 1,91.7%)and respiration department and wards(building 2,80%)than in the office building(building 3),where no M.avium was found.M.avium were more abundant in automatic faucets(average 2.21×10~4 gene copies/L)than in manual faucets(average 1.03×10~4 gene copies/m L)(P<0.01).Proteobacteria,Actinobacteria,Bacteroidetes,Cyanobacteria,Firmicutes,and Acidobacteria were the dominant bacterial phyla.Disinfectant residuals,nitrate,and temperature were found to be the key environmental factors driving microbial community structure shifts in water systems.Conclusion This study revealed a high level of colonization of water faucets by opportunistic pathogens and provided insight into the characteristics of microbial communities in a hospital water system and approaches to reduce risks of microbial contamination.
基金supported by NSF of China (11071266)partially supported by Scholarship Award for Excellent Doctoral Student granted by Ministry of Educationpartially supported by the found of Chongqing Normal University (13XLB006)
文摘In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equations is established. Some sufficient conditions for blow-up of the solutions in finite time are given. Moreover, by separation method, the self-similar solutions for the nonlinear shallow water equations are obtained, and which local or global behavior can be determined by the corresponding Emden equation.
基金supported by the National Natural Science Foundation of China(Nos.51778323,51761125013 and51290284)the National Science and Technology Major Project of China(Nos.2012ZX07404-002,2017ZX07108-003 and 2017ZX07502-003)
文摘To manage potential microbial risks and meet increasingly strict drinking water health standards,UV treatment has attracted increasing attention for use in drinking water systems in China.However,the effects of UV treatment on microbial control and disinfection byproducts(DBPs)formation in real municipal drinking water systems are poorly understood.Here,we collected water samples from three real drinking water systems in Beijing and Tianjin to investigate the impacts of UV treatment on microbial control and DBP formation.We employed heterotrophic plate count(HPC),flow cytometry(FCM),quantitative PCR analysis,and high-throughput sequencing to measure microorganisms in the samples.Different trends were observed between HPC and total cell count(measured by FCM),indicating that a single indicator could not reflect the real degree of biological re-growth in drinking water distribution systems(DWDSs).A significant increase in the 16S rRNA gene concentration was observed when the UV system was stopped.Besides,the bacterial community composition was similar at the phylum level but differed markedly at the genera level among the three DWDSs.Some chlorine-resistant bacteria,including potential pathogens(e.g.,Acinetobacter)showed a high relative abundance when the UV system was turned off.It can be concluded that UV treatment can mitigate microbial re-growth to some extent.Finally,UV treatment had a limited influence on the formation of DBPs,including trihalomethanes,haloacetic acids,and nitrogenated DBPs.The findings of this study may help to understand the performance of UV treatment in real drinking water systems.
基金supported by the Key Laboratory of Drinking Water Science and Technology, Chinese Academy of Sciences (No. 15Z01KLDWST)the National Natural Science Foundation of China (Nos. 51378491 and 51578533)
文摘A combined process was developed to inhibit the corrosion both in the pipeline of reclaimed water supplies（PRWS） and in downstream recirculating cooling water systems（RCWS）using the reclaimed water as makeup. Hydroxyl carboxylate-based corrosion inhibitors（e.g.,gluconate, citrate, tartrate） and zinc sulfate heptahydrate, which provided Zn^2＋ as a synergistic corrosion inhibition additive, were added prior to the PRWS when the phosphate（which could be utilized as a corrosion inhibitor） content in the reclaimed water was below 1.7 mg/L, and no additional corrosion inhibitors were required for the downstream RCWS.Satisfactory corrosion inhibition was achieved even if the RCWS was operated under the condition of high numbers of concentration cycles. The corrosion inhibition requirement was also met by the appropriate combination of PO4^3- and Zn^2＋ when the phosphate content in the reclaimed water was more than 1.7 mg/L. The process integrated not only water reclamation and reuse, and the operation of a highly concentrated RCWS, but also the comprehensive utilization of phosphate in reclaimed water and the application of non-phosphorus corrosion inhibitors. The proposed process reduced the operating cost of the PRWS and the RCWS, and lowered the environmental hazard caused by the excessive discharge of phosphate. Furthermore, larger amounts of water resources could be conserved as a result.
文摘The energy saving issue of chilled water system in an intelligent building is analyzed from the systematic point of view, and an optimum scheduling scheme which can save energy of the system facilities and satisfy the constraints of the real time cold loads and system running is also proposed. It can make the minimum cost of the system by optimizing the number of running chillers, running parameters and the distribution of real time loads of running chillers. The improved genetic algorithm is used in the optimum scheduling scheme. The computation results show that the building energy consumption can be decreased by about 10%.
基金supported by the National Natural Science Foundation of China(No.21137003,20890111)the Natural Science Foundation of Zhejiang Province(No.Z5090031)the Key Innovation Team for Science and Technology of Zhejiang Province,China(No.2009R50047)
文摘An integrative technology including the surfactant enhanced sorption and subsequentdesorption and biodegradation of phenanthrene in the soil-water system was introduced and tested. For slightly contaminated agricultural soils, cationic-nonionic mixed surfactant- enhanced sorption of organic contaminants onto soils could reduce their transfer to plants, therefore safe-guarding agricultural production. After planting, residual surfactants combined with added nonionic surfactant could also promote thedesorption and biodegradation of residual phenanthrene, thus providing a cost-effective pollution remediation technology.0ur results showed that the cationic-nonionic mixed surfactantsdodecylpyridinium bromide （DDPB） and Triton X-100 （TX100） significantly enhanced soil retention of phenanthrene. The maximum sorption coefficient Kd＊ of phenanthrene for contaminated soils treated by mixed surfactants was about24.5 times that of soils without surfactant （Kd ） and higher than the combined effects of DDPB and TX100 individually, which was about 16.7 and 1.5 times Kd , respectively.0n the other hand, TX100 could effectively remove phenanthrene from contaminated soils treated by mixed surfactants, improving the bioavailability of organic pollutants. Thedesorption rates of phenanthrene from these treated soils were greater than 85% with TX100 concentration above2000 mg/L and approached 100% with increasing TX100 concentration. The biodegradation rates of phenanthrene in the presence of surfactants reached over 95% in30days. The mixed surfactants promoted the biodegradation of phenanthrene to some extent in 10-22days, and had no obvious impact on phenanthrene biodegradation at the end of the experiment. Results obtained from this study provide some insight for the production of safe agricultural products and a remediation scheme for soils slightly contaminated with organic pollutants.
文摘Demand response(DR)is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation.Changes in electricity markets regulation in several countries have recently enabled an effective integration of DR mechanisms in power systems.Through its flexible components(pumps,tanks),drinking water systems are suitable candidates for energy-efficient DR mechanisms.However,these systems are often managed independently of power system operation for both economic and operational reasons.Indeed,a sufficient level of economic viability and water demands risk management are necessary for water utilities to integrate their flexibilities to power system operation.In this paper,we proposed a mathematical model for optimizing pump schedules in water systems while trading DR blocs in a spot power market during peak times.Uncertainties about water demands were considered in the mathematical model allowing to propose power reductions covering the potential risk of real-time water demand forecasting inaccuracy.Numerical results were discussed on a real water system in France,demonstrating both economic and ecological benefits.
文摘In this article VLE data for a ternary system (propylene-methanol-water) under 30～60 C,0. 3～0. 9 MPa with a mass ratio of methanol to water of 9:1, 8: 2, 7: 3 were determined with a static equilibrium still, and were correlated by using Peng-Robinson model. The average relative error ofpropylene concentration in liquid phase is 1. 46 %. The results indicate that the models are very suitablefor the ternary system and the data are reliable.
