检索结果-南通市图书馆

Degradation of sulfonamides and formation of trihalomethanes by chlorination after pre-oxidation with Fe(Ⅵ)

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2018年第11期30卷 89-95页

作者： tuqiao zhang Feilong Dong Feng Luo Cong Li College of Civil Engineering and Architecture ZhejiangUniversity Hangzhou 310027 China

Sulfonamides are used in human therapy, animal husbandry and agriculture but are not easily biodegradable, and are often detected in surface water. Sulfamethazine （SMZ） and sulfadiazine （SDZ） are two widely used sulfonamide antibiotics that are used heavily in agriculture. In this study, they were degraded in an aqueous system by chlorination after pre-oxidation with ferrate（VI）（FeVIO2-, Fe（VI））, an environmentally friendly oxidation technique that has been shown to be effective in degrading various organics. The kinetics of the degradation were determined as a function of Fe（VI）（0-1.5 mg/L）, free chlorine （0-1.8 mg/L） and temperature （15- 35℃）. According to the experimental results, SMZ chlorination followed second-order kinetics with increasing Fe（VI） dosage, and the effect of the initial free chlorine concentration on the reaction kinetics with pre-oxidation by Fe（VI） fitted a pseudo-first order model. The rate constants of SDZ and SMZ chlorination at different temperatures were related to the Arrhenius equation. Fe（VI） could reduce the levels of THMs formed and the toxicity of the sulfonamide degradation systems with Fe（VI） doses of 0.5-1.5 mg/L, which provides a reference for ensuring water quality in drinking water systems.

关键词： Ferrate(VI) Sulfadiazine Sulfamethazine Free chlorine Trihalomethanes

Characterization of typical taste and odor compounds formed by Microcystis aeruginosa

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2013年第8期25卷 1539-1548页

作者： Kejia zhang Tsair Fuh Lin tuqiao zhang Cong Li Naiyun Gao College of Civil Engineering and Architecture Zhejiang University Department of Environmental Engineering National Cheng Kung University State Key Laboratory of Pollution Control and Resource Reuse Tongji University

Production and characteristics of typical taste and odor （T＆O） compounds by Microcystis aeruginosa were investigated. A few terpenoid chemicals, including 2-MIB, β-cyclocitral, and β-ionone, and a few sulfur compounds, such as dimethyl sulfide and dimethyl trisulfide, were detected. β-Cyclocitral and β-carotene concentrations were observed to be relevant to the growth phases of Microcystis. During the stable growth phase, 41-865 fg/cell of β-cyclocitral were found in the laboratory culture. β-Cyclocitral concentrations correlated closely with β-carotene concentrations, with the correlation coefficient R2 = 0.96, as it is formed from the cleavage reaction of β-carotene. For dead cell cases, a high concentration of dimethyl trisulfide was detected at 3.48-6.37 fg/cell. Four T＆O compounds, including β-cyclocitral, β-ionone, heptanal and dimethyl trisulfide, were tested and found to be able to inhibit and damage Microcystis cells to varying degrees. Among these chemicals, β-cyclocitral has the strongest ability to quickly rupture cells.

关键词： Microcystis aeruginosa T&O compounds β-cyclocitral algae-lytic effect

Removal of antibiotic-resistant genes during drinking water treatment:A review

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2021年第6期33卷 415-429页

作者： tuqiao zhang Kunyuan Lv Qingxiao Lu Lili Wang Xiaowei Liu Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology Zhejiang UniversityHangzhou 310058China Ocean College Zhejiang UniversityHangzhou 310058China Environmental Engineering Jiyang College of Zhejiang A&F UniversityZhuji 311800China

Once contaminate the drinking water source,antibiotic resistance genes(ARGs)will propagate in drinking water systems and pose a serious risk to human ***,the drinking water treatment processes(DWTPs)are critical to manage the risks posed by *** study summarizes the prevalence of ARGs in raw water sources and treated drinking water *** addition,the removal efficiency of ARGs and related mechanisms by different DWTPs are *** and biotic factors that affect ARGs elimination are also *** data on presence of ARGs in drinking water help come to the conclusion that ARGs pollution is prevalent and deserves a high ***,DWTPs indeed achieve ARGs removal,but some biological treatment processes such as biological activated carbon filtration may promote antibiotic resistance due to the enrichment of ARGs in the *** finding that disinfection and membrane filtration are superior to other DWTPs adds weight to the advice that DWTPs should adopt multiple disinfection barriers,as well as keep sufficient chlorine residuals to inhibit re-growth of ARGs during subsequent ***,DWTPs obtain direct and inderect ARGs reduction through DNA damage and interception of host bacterias of ***,escaping of intracellular ARGs to extracellular environment,induced by DWTPs,should be *** review provides the theoretical support for developping efficient reduction technologies of *** study should focus on ARGs controlling in terms of transmissibility or persistence through DWTPs due to their biological related nature and ubiquitous presence of biofilm in the treatment unit.

关键词： Antibiotic resistance genes Drinking water treatment processes Removal mechanism Influencing factors

Comparison of UV/PDS and UV/H_2O_2 processes for the degradation of atenolol in water

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2013年第8期25卷 1519-1528页

作者： Xiaowei Liu Lei Fang Yongchao Zhou tuqiao zhang Yu Shao Institute of Municipal Engineering College of Civil Engineering and Architecture Zhejiang University

UV/H2O2 and UV/peroxodisulfate （PDS） processes were adopted to degrade a typical β-blocker atenolol （ATL）. The degradation efficiencies under various operational parameters （oxidant dosage, pH, HCO3-, humic acid （HA）, NO3- , and Cl-） were compared. Principal factor analysis was also performed with a statistical method for the two processes. It was found that increasing the specific dosage of the two peroxides （[peroxide]0/[ATL]0 ） ranging from 1：1 to 8：1 led to a faster degradation rate but also higher peroxide residual. Within the pH range 3-11, the optimum pH was 7 for the UV/PDS process and elevating pH benefitted the UV/H 2O2 process. The presence of HCO3- , HA, and Cl adversely affected ATL oxidation in both processes. The NO3- concentration 1-3 mmol/L accelerated the destruction of ATL by the UV/PDS process, but further increase of NO3- concentration retarded the degradation process, contrary to the case in the UV/H2O2 process. The rank orders of effects caused by the six operational parameters were pH ≈ specific dosage 〉 [HA]0 〉 [NO3-]0 〉 [HCO3-]0 〉 [Cl-]0 for the UV/H2O2 process and specific dosage 〉 pH 〉 [HA]0 〉 [NO3-]0 〉 [HCO3-]0 〉[Cl-]0 for the UV/PDS process. The UV/PDS process was more sensitive to changes in operational parameters than the UV/H2O2 process but more efficient in ATL removal under the same conditions.

关键词： sulfate radical hydroxyl radical atenolol influencing factors rank order

Optimal Dispatching of Large-scale Water Supply System

在线全文

学校读者我要写书评

暂无评论

High Technology Letters 2003年第2期9卷 21-26页

作者：吕谋 SONG Shuang Zhao Hongbin zhang tuqiao Department of Civil Engineering Zhejiang University Hangzhou 310013 P.R.China Department of Environmental Engineering Zhejiang University of Technology Hangzhou 310032 P.R.China Department of Municipal Engineering Harbin Institute of Technology Harbin 150001 P.R.China

This paper deals with the use of optimal control techniques in large-scale water distribution networks. According to the network characteristics and actual state of the water supply system in China, the implicit model, which may be solved by utilizing the hierarchical optimization method, is established. In special, based on the analyses of the water supply system containing variable-speed pumps, a software tool has been developed successfully. The application of this model to the city of Shenyang (China) is compared to experiential strategy. The results of this study show that the developed model is a very promising optimization method to control the large-scale water supply systems.

关键词： optimal dispatching water supply system water networks implicit model hierarchical optimization

Application of Ice Pigging in a Drinking Water Distribution System:Impacts on Pipes and Bulk Water Quality

在线全文

学校读者我要写书评

暂无评论

Engineering 2024年第9期40卷 122-130页

作者： Yujing Huang Zhiwei Chen Guilin He Yu Shao Shuang Song Feilong Dong tuqiao zhang College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310027China Suzhou Wuzhong Water Co. Ltd.Suzhou 215128China School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China College of Environment Zhejiang University of TechnologyHangzhou 310014China

Ice pigging is an emerging technique for pipe cleaning in drinking water distribution ***,substantial confusion and controversy exist on the potential impacts of ice pigging on bulk water *** study monitored the microstructural features and composition of sediments and microbial community structures in bulk water in eight multimaterial Chinese *** concentration analysis demonstrated that separate cleaning of pipes with different materials in complex networks could mitigate the risk of losing ice pigs and degrading water *** microstructural and trace element characterization results showed that ice pigs would scarcely disturb the inner surfaces of long-used *** bacterial richness and diversity of bulk water decreased significantly after ice ***,correlations were established between pipe service age,temperature,and chloride and total iron concentrations,and the 15 most abundant taxa in bulk water,which could be used to guide practical ice pigging operations.

关键词： Ice pigging Pipe cleaning Drinking water distribution system Bacterial community Sediments

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

提高支持向量机洪水峰值预报精度研究

水力发电学报 2005年第2期24卷 35-39页

作者：张土乔俞亭超浙江大学土木工程学系杭州310027

本文引入支持向量机算法进行流域洪水预报建模 ,同时针对训练样本的不平衡性 ,提出了一种能进行峰值识别的改进支持向量机算法 (SupportVectorMachinewithPeakRecognizer ,简称SVMPR)。该算法在结构风险最小化准则的目标函数中适当加大... 详细信息

本文引入支持向量机算法进行流域洪水预报建模 ,同时针对训练样本的不平衡性 ,提出了一种能进行峰值识别的改进支持向量机算法 (SupportVectorMachinewithPeakRecognizer ,简称SVMPR)。该算法在结构风险最小化准则的目标函数中适当加大峰值样本的权重 ,从而提高支持向量机洪水预报模型对洪峰的预报精度。分别采用SVM算法和SVMPR算法对沙溪口流域上洋口站建立洪水预报模型 ,对比分析表明了SVMPR算法的有效性。

关键词：防洪工程洪水预报支持向量机峰值识别理论

在线全文

学校读者我要写书评

暂无评论

埋地灰口铸铁管失效预测模型及影响参数分析

同济大学学报（自然科学版） 2010年第6期38卷 805-809页

作者：邵煜张土乔俞亭超浙江大学土木工程学系浙江杭州310058

针对研究解决早期埋设的灰口铸铁管存在的破损频繁、漏失严重等影响输配水安全问题,运用管土相互作用受力模型得到管道应力,结合灰口铸铁管的腐蚀模型、剩余强度评价方法和失效准则,得到管道失效预测模型,最终利用蒙特卡罗方法计算管道... 详细信息

针对研究解决早期埋设的灰口铸铁管存在的破损频繁、漏失严重等影响输配水安全问题,运用管土相互作用受力模型得到管道应力,结合灰口铸铁管的腐蚀模型、剩余强度评价方法和失效准则,得到管道失效预测模型,最终利用蒙特卡罗方法计算管道可靠度,并进行影响参数分析.计算结果表明:大直径管道失效主要由环向应力控制,而小直径管道失效多为纵向应力控制;由于渗漏或不均匀沉降引起的管道基础局部流失在腐蚀深度超过一定深度时对失效概率的影响较大;腐蚀模型参数、未支撑长度、剩余强度参数对安全因子分布具有重要影响.腐蚀是影响灰口铸铁管失效的重要因素,意在减缓腐蚀速度的管道防腐技术可以有效减少管道的失效频率,延长管道使用寿命.

关键词：管土相互作用腐蚀灰口铸铁管失效预测影响参数可靠度

在线全文

学校读者我要写书评

暂无评论

基于遗传算法的供水系统一级优化调度研究

同济大学学报（自然科学版） 2006年第6期34卷 776-781页

作者：俞亭超张土乔潘莉莉浙江大学土木工程系浙江杭州310027

根据多水源多水塔供水系统的网络特性,以测压点压力宏观模型、水源供水量和水头之间的关系模型,替代管网水力平衡方程,并以泵站的供水压力、水塔初始水头为决策变量,建立了供水系统一级优化调度模型.采用罚函数法将各种约束转化为目标函... 详细信息

根据多水源多水塔供水系统的网络特性,以测压点压力宏观模型、水源供水量和水头之间的关系模型,替代管网水力平衡方程,并以泵站的供水压力、水塔初始水头为决策变量,建立了供水系统一级优化调度模型.采用罚函数法将各种约束转化为目标函数,然后利用乘除法将多目标优化转化为单目标优化问题,最后利用遗传算法求解.针对遗传算法容易早熟等不足,将遗传算法和模拟退火技术相结合,并采用自适应交叉和变异率的解决方法.算例计算表明,该算法具有较强的适用性.

关键词：供水系统优化调度遗传算法