北京奥林匹克森林公园水系水质模拟和维护系统设计

为了体现"绿色奥运、科技奥运、人文奥运"的宗旨,保障奥林匹克森林公园水系统的可持续发展。通过水文水质模型的研究与景观功能和实用性相结合的复合湿地的设计,制定维持奥林匹克森林公园水系的水量和水质保障的技术方案,通过经济和技术比较,选择较优方案进行相应的工程方案设计。设计过程中采用的方法具有一定的普遍性,可以用于其它规划水系的模拟、分析以及保障方案的制定和评价。

南昌市水系水质现状、问题及改善对策

水作为城市的眼睛,城市水系水质状况好坏关系到城市容貌、关系到城市的生产生活安全,也关系到市民的身心健康,更关系着城市的可持续发展。本文以江南水城代表南昌水系水质状况来进行研究,从1、南昌市的水系水质的现状,2、南昌市水系水质存在的问题,3、南昌市水系水质改善对策,三部分来阐述。

北京奥林匹克森林公园水质数学模拟和水系维护系统设计

设计力图体现“绿色奥运、科技奥运、人文奥运”的宗旨,保障奥林匹克森林公园水系统的可持续发展。通过水文水质模拟的研究以及将景观功能和实用性相结合的复合湿地的设计,制定维持奥林匹克森林公园水系水量和水质保障的技术方案;通过经济和技术比较,选择较优方案进行相应的工程方案设计。设计过程中采用的方法具有一定的普适性,可以用于其他景观水系规划的模拟、分析以及保障方案的制定和评价。

官厅水库供水系统水质水量控制的研究

本文应用确定性水质水量模型,分析计算出满足官厅水库供水系统水质目标所相应需要的最小放水流量,并定量分析了因水质要求而加大的放水量对工业用水保证率产生的影响。

铁山隧道碳酸钙水质结晶堵塞排水系统病害整治简析

本文以营达高速公路铁山隧道为例,对隧道碳酸钙水质结晶堵塞排水系统病害问题进行简要分析,并提出整治措施。

一种低磷缓蚀阻垢剂TH-682在不同水质中的性能研究

TH-682是一种新型缓蚀阻垢剂,具有含磷低,缓蚀阻垢性能好的特点。对全国五大水域水质,特别是南方水系的超低硬度、腐蚀性较强的水质,TH-682具有良好的缓蚀效果;加药量为60 mg/L时,其碳钢腐蚀速率均符合GB50050—2007标准。不同药剂量下,TH-682的静态阻垢率均高于HEDP、ATMP和国外药剂-A。通过电厂低硬度、强腐蚀水现场应用一年,TH-682的缓蚀阻垢效果良好。并且TH-682含磷低,仅为4.8%,可以有效避免磷的水中富营养化问题。

基于变权物元的改进可拓评价法在输配水工程水质评价中的应用

合理的水质评价方法是城市输配水工程中水质综合评价的关键。文章采用改进变权物元可拓评价法和敏感分析法,利用2015年沈阳输配水工程中东配水厂、西配水厂、东净水厂及西净水厂四个测点的水质监测资料对四个测点的水质进行了综合评价,同时分析各指标变化对水质综合评价结果的影响。评价结果表明:2015年沈阳配水系统中四个测点的水质等级均为清洁,且偏向于较清洁等级的程度较大。通过敏感性分析得出,"pH"和"总氮"是影响输配水工程四个测点水质综合评价结果的敏感性指标。

Water Quality Evaluation Index System for Freshwater Aquaculture Pond

[Objective] The aim was to establish the water quality evaluation index system for freshwater aquaculture pond.[Method] The expert survey,DELPHI,field research and other methods were used.Based on the analysis of factors influencing water quality of freshwater aquaculture pond,and the importance degree of 14 factors influencing water quality of freshwater aquaculture pond was ordered.Then,five factors were selected as index to establish the water quality evaluation index system of freshwater aquaculture with the determination for thresholds of these factors.[Result] The importance degree of water quality of freshwater aquaculture pond showed an order of Dissolved oxygenpHPhytoplankton biomassSecchi depthTotal NitrogenZooplankton biomassWater temperatureBiochemical Oxygen DemandWater colorSalinityTotal hardness;according to the value of importance degree,the dissolved oxygen,pH,secchi depth,phytoplankton biomass and total nitrogen these five factors were selected as the index system of water quality evaluation of pond.The level of water quality of freshwater aquaculture pond was divided into five,and the tolerance range of fish to each index was obtained by expert observation.[Conclusion] This study had provided a scientific basis for water quality evaluation system of freshwater aquaculture pond.

城市生活用水节水新措施的探讨

从不同角度和侧面揭示了我国城市水资源的严重不足和采取的新措施 ,揭示了人们用水观念的严重滞后。针对上述问题 ,提出了不同解决办法。提高人们的节水意识 ,减少对周围水体的污染。从经济的角度出发 ,对水资源进行综合的开发和利用。作为节水技术 ,分质供水 ,中水技术及相应地在用水管理措施 ,新型节水型用水设备的开发方面 ,将在 2

Chemical and Microbiological Parameters of Paddy Soil Quality as Affected by Different Nutrient and Water Regimes

A field experiment was conducted from 1999 to 2002 to compare and evaluate the effects of nutrient and water regimes on paddy soil quality by investigating soil chemical and microbiological parameters. Four nutrient regimes, a control, chemical fertilizers only (CF), chemical fertilizers with swine manure (SM), and chemical fertilizers with wheat straw (WS), and two soil moisture regimes, continuous waterlogging (CWL) and alternate wetting and drying (AWD), were investigated. With SM and WS total organic carbon and total nitrogen in the paddy soil were significantly higher (P < 0.05) than those with CF. A similar effect for organic amendments was observed in the soil light fraction organic C (LFOC), water-soluble carbohydrates (WSC), and water-soluble organic C (WSOC). CWL, in particular when swine manure was incorporated into the paddy soil, markedly decreased soil redox potential (Eh) and increased total active reducing substances (ARS). Meanwhile, as compared to CF, SM and WS significantly (P < 0.05) increased soil microbial biomass C (MBC) and mineralizable carbon, with differences in AWD being higher than CWL. In addition, SM and WS treatments significantly (P < 0.05) improved rice above-ground biomass and grain yield, with AWD being greater than CWL. Thus, for ecologically sustainable agricultural management of paddy soils, long-term waterlogging should be avoided when organic manure was incorporated into paddy soil.

Assessment on reliability of water quality in water distribution systems

Water leaving the treatment works is usually of a high quality but its properties change during the transportation stage. Increasing awareness of the quality of the service provided within the water industry today and assessing the reliability of the water quality in a distribution system has become a major significance for decision on system operation based on water quality in distribution networks. Using together a water age model, a chlorine decay model and a model of acceptable maximum water age can assess the reliability of the water quality in a distribution system. First, the nodal water age values in a certain complex distribution system can be calculated by the water age model. Then, the acceptable maximum water age value in the distribution system is obtained based on the chlorine decay model. The nodes at which the water age values are below the maximum value are regarded as reliable nodes. Finally, the reliability index on the percentile weighted by the nodal demands reflects the reliability of the water quality in the distribution system. The approach has been applied in a real water distribution network. The contour plot based on the water age values determines a surface of the reliability of the water quality. At any time, this surface is used to locate high water age but poor reliability areas, which identify parts of the network that may be of poor water quality. As a result, the contour water age provides a valuable aid for a straight insight into the water quality in the distribution system.

Variability of micropollutants and microorganisms in water distribution system

The variation of water quality in water distribution system was investigated with assimilable organic carbon (AOC)and trihalomethanes(THMs) used as assessment indexes. Bacterium was identified in water distribution. The result showed that there were pathogenic parasites in water distribution system. The variation of AOC is related to chlorine residual and bacterium activity, and AOC concentration decreased first and then increased with the extension of water distribution system. The formation of THMs was related to the consumption of chlorine inside the distribution system, and THMs concentration increased with the extension of water pipe line.

Spatiotemporal Variation of Riverine Nutrients in a Typical Hilly Watershed in Southeast China Using Multivariate Statistics Tools

The water quality of lakes can be degraded by excessive riverine nutrients.Riverine water quality generally varies depending on region and season because of the spatiotemporal variations in natural factors and anthropogenic activities.Monthly water quality measurements of eight water quality variables were analyzed for two years at 16 sites of the Tianmuhu watershed.The variables were examined using hierarchical cluster analysis(HCA) and factor analysis/principal component analysis(FA/PCA) to reveal the spatiotemporal variations in riverine nutrients and to identify their potential sources.HCA revealed three geographical groups and three periods.Two drainages comprising towns and large villages were the most polluted, six drainages comprising widely distributed tea plantations and orchards were moderately polluted, and eight drainages without the factors were the least polluted.The river was most polluted in June when the first heavy rain(daily rainfall > 50 mm) occurs after fertilization and the number of rainy days is most(monthly number of rainy days > 20 days).Moderate pollution was observed from October to May, during which morethan 60% of the total nitrogen fertilizer and all of the phosphorus fertilizer are applied to the cropland, the total manure is applied to tea plantations and orchards, and a monthly rainfall ranging from 0 mm to 164 mm occurs.The remaining months were characterized by frequent raining(i.e., number of rainy days per month ranged from 5 to 24) and little use of fertilizers, and were thus least polluted.FA/PCA identified that the greatest pollution sources were the runoff from tea plantations and orchards,domestic pollution and the surface runoff from towns and villages, and rural sewage, which had extremely high contributions of riverine nitrogen, phosphorus,and chemical oxygen demand, respectively.The tea plantations and orchards promoted by the agricultural comprehensive development(ACD) were not environmentally friendly.Riverine nitrogen is a major water pollution parameter in hilly watersheds affected by ACD, and this parameter would not be reduced unless its loss load through the runoff from tea plantations and orchards is effectively controlled.

Minimization of the Flowrate of Fresh Water and Corresponding Regenerated Water in Water-using System with Regeneration Reuse

A sequential three-step programming method is proposed for determining the minimum flowrate of fresh water and corresponding regenerated water in water-using system of single contaminant with regeneration reuse. In step 1, a programming with the objective of min fws is used to determine the minimum flowrate of fresh water, in which the mathematical representation is a mixed integer nonlinear programming (MINLP1). Then under the same constraints with step 1, a programming with the objective of min freg in step 2 and a programming with the objective of min Cr in step 3 are subsequently used to determine the minimum flowrate of regenerated water and the minimum inlet concentration to regeneration process corresponding to the minimum flowrate of fresh water based on step 1. The method is easy to apply because we only need to change the objective function but keep the constraints constant to go along the following steps after step 1. In addition, the relationship between the fresh water flowrate required, fws and inlet concentration to regeneration process, Cr, is investigated. It is found that there exist three relationships between fws and Cr, which indicate three possibilities for C\>: below the pinch, above the pinch or at the pinch. Therefore, a new conclusion is drawn, which differs from that 'regeneration of water at pinch minimizes fresh water flowrate' derived in literature and indicates that in some cases, regeneration at other point also minimizes fresh water flowrate.

Landslide stability for Shuitianba in the Three Gorges area

According to the data of preliminary survey, the authors established a landslide geological model,on the basis of analyses on the sensitivity of landslide, tried to simulate and calculate the landslide stability of Shuitianba with the method of transfer coefficient when it is under different strength parameters, and study the landslide mechanism. The results show that it is sensitive to the effects of shear strength parameters of sliding zone and groundwater level on landslide stability safety coefficient, which provides reliable basis for calculation of landslide stability.

Study on Water Pollution Control of Huaihe River and Countermeasures

Huaihe River is one of three major rivers in China with a large population and developed economy. By the 1970s, the water quality of Huaihe River was deteriorating daily and more than a hundred serious pollution accidents of water quality happened and caused the inestimable losses in the production, life and health of residents along the river and terribly damaged the ecological system of the river. Through the continuous large-scale treatment for more than 10 years, the deterioration of water quality in Huaihe River has been basically inhibited. Nevertheless, the water pollution in Huaihe River is, on the whole, still very serious for many reasons, including special climatic conditions, terrible lack of water resource, obsolete industrial structure and unsound management system for the river, etc. This essay deeply analyzes the rea- sons why the water pollution of Huaihe River is ＂chronic＂ and puts forward the corresponding countermeasures for how to continuously improve the water quality of the river. In the end, this essay argues that it still takes 30-50 years or even a longer period, even if every measures are implemented smoothly and strictly, to actually make the water of Huaihe River clean and gradually restore its normal ecological and environmental functions.

Eutrophication of Aquatic Ecosystems： A Viewpoint on the Environmental Impact of Climate Change

Environmental concerns associated with nutrient-oriented eutrophication phenomenon have become a serious issue and a major cause of water quality deficiency nowadays. This necessitated eutrophication to occupy a front seat in research accompanied with climate change. Climate change has revealed to be a key player and a main contributor in the occurrence of such phenomenon. This paper discusses the ever-growing concern about eutrophication as a cause of climate change. Climate change affects storms intensity, changing the precipitation regime and increasing temperature. These effects increase the nutrient loading diffusion and cause excessive nutrients accompanied with storm water runoff, domestic wastewaters, and agricultural discharges to pour into water bodies. Eutrophication conversely contributes in the global wanning by releasing greenhouse gases from deoxygenated waters and sediments. Some control and mitigation measures are needed to fight climate change and achieve desired water quality goals. These measures include mitigation of climate change causes, enhancement of natural ecohydrological processes, application of proper integrated water resource management and participation of communities and governments.

Column Analyses of Chloride Breakthrough and Lead Retention in Amended Sandy Soils

Stormwater quality design manuals lack scientifically creditable bases for many novel LID （Low-Impact Development） designs presently proposed to meet stormwater runoff management requirements. Potential stormwater pollutant adsorption and infiltration enhancement capabilities of forest-derived by-products （e.g. woodchips, bio-char） provide an opportunity to combine these readily availability materials into stormwater quality designs. On-site stormwater runoff treatment through determination of the soil-water transport and lead （Pb） retention capacity of two sandy soils from Oregon is considered. Using synthetic stormwater （-120 mg CI/L and -5 mg Pb/L） displacement tests in pairs ofABS （Acrylonitrile butadiene styrene） soil columns （75 mm dia by 0.46 m tall） with upward flow （to minimize air entrapment） saturated hydraulic conductivity, chloride dispersion and Pb retention by plain and amended soils is evaluated. Generally, soil amendment incorporation （woodchips, compost or biochar） as compared to an amendment layer resulted in improved hydraulic conductivities as compared to that of the soil alone. Chloride breakthrough curves verified that resident soil-water displacement occurred with 0.9 to 1.6 pore volumes and residence times for most columns were 15-30 minutes. No synthetic stormwater Pb ＂breakthrough＂ within the displaced or replaced soil-water was found, rather most Pb was adsorbed within the first 150 mm of soil.

Study of Water Relations and Solutes Accumulation in Two Rice Genotypes under NaCI Stress during Seedling Stage

In order to study osmotic adjustment and accumulation of anions and cations in rice （Oryza sativa L.） seedlings under NaCl stress, a greenhouse experiment was conducted using two rice cultivars including IR651 （tolerant） and IR29 （sensitive）. Seedlings were grown in Youshida nutrient solution. Salinity treatments were imposed 21 days after sowing with 0 and 100 mM NaCI and seedlings were harvested 0, 72, 120 and 240 hour after salinization. Water （ψw） and osmotic （ψs） potentials, total soluble sugars and inorganic ions （Na＋. K＋, Cl-, Ca2＋ and Mg2＋） concentrations and osmotic adjustment were determined in sixth （youngest） leaf. Salinity caused a substantial biomass reduction in rice seedlings, ψs reduction in IR29 was occurred more than IR651. Water potential decreased in both the cultivars under stress conditions, but IR651 was able to maintain higher ψw and kept better growth till the end of the experiment. Osmotic adjustment was observed in IR651 was about 10 times more than in IR29. K＋ accumulation decreased in both cultivars under stress condition while Na＋ accumulation increased in both the cultivars with higher increase in IR29 seedlings. CI concentration increased in youngest leaf of both IR29 and IR651. Our results showed that tolerant cultivar was able to make osmotic adjustment faster than the sensitive cultivar using high accumulation of solutes especially total soluble sugars.

Aqueous Supercapacitors With Wide Operative Voltage Window and Long Cycling Life Enabled by Electrolyte Hybridization Effect

Developing supercapacitors(SCs)with long cycling life and wide operative voltage window is a significant topic in the field of aqueous electrolytes.Although the design of water in salt(WIS)electrolytes has pushed the development of aqueous electrolytes to a new height,the WIS electrolytes with an operative voltage window of up to 2.5 V is still very scarce.Herein,in order to enrich the type of aqueous electrolyte with high operative voltage,tetramethylammonium trifluoromethanesulfonate(TMAOTf)based WIS electrolyte was used as a model to construct WIS based hybrid electrolyte with acetonitrile(ACN)co-solvent and LiTFSI co-solute.In view of the coordination effect of ACN and Lit on free water in TMAOTf based WIS electrolyte,the TMAt-Lit-AWIS electrolyte has the electrochemical stabilization window of up to 3.35 V.Further coupled with the commercial YP-50F electrodes,TMAt-Lit-AWIS based SCs exhibited wide operative voltage window(2.5 V),long cycling life(45,000 cycles)and good low-temperature performance(99.99%capacitance retention after 2000 cycles at20℃).The design of this hybrid electrolyte will enrich the types of aqueous hybrid electrolytes with long cycling life and wide operative voltage window.