Ordered mesoporous materials for water pollution treatment:Adsorption and catalysis

To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environmental processing applications due to their exceptionally high surface areas,large pore sizes,and enough pore volumes.These properties might enhance the performance of materials concerning adsorption/catalysis capability,durability,and stability.In this review,we enumerate the ordered mesoporous materials as adsorbents/catalysts and their modifications in water pollution treatment from the past decade,including heavy metals(Hg^(2+),Pb^(2+),Cd^(2+),Cr^(6+),etc.),toxic anions(nitrate,phosphate,fluoride,etc.),and organic contaminants(organic dyes,antibiotics,etc.).These contributions demonstrate a deep understanding of the synergistic effect between the incorporated framework and homogeneous active centers.Besides,the challenges and perspectives of the future developments of ordered mesoporous materials in wastewater treatment are proposed.This work provides a theoretical basis and complete summary for the application of ordered mesoporous materials in the removal of contaminants from aqueous solutions.

Progress of Electrocatalytic Technology in Treating Organic Chemical Wastewater

In recent years,extensive research has been conducted on the preparation of high catalytic performance electrodes and the development of electrocatalytic water treatment processes.This article introduces the basic principles of electrochemical water treatment,the preparation of electrode materials,and the research progress of electrocatalytic technology for degrading organic chemical wastewater.It analyzes the problems faced by electrocatalytic degradation of organic chemical wastewater and looks forward to the development trend of electrocatalytic technology in the field of organic chemical wastewater treatment.

Pollution of Environmental Endocrine Disrupting Chemicals(EDCs) in Water and Its Adverse Reproductive Effect on Fish

Environmental endocrine disrupting chemicals （EDCs）, commonly found in the environment, come from industry and agriculture, including pesticides, fungicides, insecticides, herbicides, and other chemicals. Nowadays, more and more EDCs were released into the environment. EDCs go into water body via atmosphere sedi-mentation, surface runoff, soil eluviation, etc., so water body becomes the main place for existing. In order to attract scientific and public attention worldwide and to prevent EDCs pol ution, in this study we reviewed the classification of EDCs and their concentrations in natural water bodies, drinking water sources and water plants, and the reproductive toxicity of EDCs to fish were reviewed. EDCs could disturb the endocrine system and make reproductive organs and reproduction abnor-mal, resulting in fertility descending, reproduction function damage, community quan-tity decrease and even species extinction. In addition, EDCs could disrupt the homeostasis maintained by hormones, which would result in defects of neural de-velopment and abnormalities of the endocrine and reproductive systems. The exact molecular mechanisms have not been completely reported, but researches have suggested that multiple mechanisms were involved in the action of EDCs. Although there have been researches on the biohazard of EDCs, there stil exist problems of weakness in fundamental researches, difficulties in recognizing and identifying EDCs and high cost, which restraint the knowledge on them.

The Fulfillment of Government Responsibilities in the Collaborative Governance of Rural Water Pollution

Rural environmental pollution is becoming more and more serious, which has become an important problem to be solved urgently in our country under the background of the new era. Protecting the ecological environment is one of the important functions of the government, and protecting the rural water environment is the unshirkable responsibility of the local governments. As the main body of rural water pollution control, how to define and fulfill the local governments’ responsibilities is of great significance to the advancement of the overall governance work. This paper starts from the local governments, which are the important main body of rural environmental governance. By comparing the similarities and differences between the performance of government responsibilities under the traditional governance model and the collaborative governance model, clarifies the governance responsibilities of the local governments. And further explores the effective measures for the government to play the main role, fulfill the main responsibilities, and participate in the collaborative governance of rural water pollution.

Evaluating the Effects of Sustainable Chemical and Organic Fertilizers with Water Saving Practice on Corn Production and Soil Characteristics

The rapidly growing world population,water shortage,and food security are promising problems for sustainable agriculture.Farmers adopt higher irrigation and fertilizer applications to increase crop production resulting in environmental pollution.This study aimed to identify the long-term effects of intelligent water and fertilizers used in corn yield and soil nutrient status.A series of field experiments were conducted for six years with treatments as:farmer accustomed to fertilization used as control(CON),fertilizer decrement(KF),fertilizer decrement+watersaving irrigation(BMP1);combined application of organic and inorganic fertilizer+water-saving irrigation(BMP2),and combined application of controlled-release fertilizer(BMP3).A significant improvement was observed in soil organic matter(14.9%),nitrate nitrogen(106.7%),total phosphorus(23.9%),available phosphorus(26.2%),straw yield(44.8%),and grain yield(54.7%)with BMP2 treatment as compared to CON.The study concludes that integrating chemical and organic fertilizers with water-saving irrigation(BMP2)is a good approach to increasing corn productivity,ensuring water safety and improving soil health.The limitations of the current study include the identification of fertilizer type and its optimum dose,irrigation water type,and geographical position.

Discussion on the Construction of Negotiation Mechanism of Cross-bounder Water Pollution Treatment in Changjiang River

In order to construct cooperation platform for the treatment of water pollution in Changjiang River,thoughts and revolution were performed from both central government and regional area two aspects.From the national level,Changjiang region water resources management cooperation counsel committee was constructed as the national cooperation platform;from the regional level,Changjiang region water resources management cooperation counsel committee was constructed as the platform of Changjiang cooperation platform.The two platforms built fine interaction mechanism to deal with the national water management and Changjiang regional water management.

Numerical simulation of pollutant diffusion and decay process after a water pollution incident in the Three Gorges Reservoir

We established a hydrodynamic model to simulate the pollutant transport and decay process in the case of a pollution incident in the sections of the Yangtze and the Jialing passing through the city area of Chongqing. The Boussinesq assumptions and the Navier-Stokes equations of incompressible fluid were applied to setting up the pollutant diffusion equations and the equations for the decay process. E. colt was taken as the example pollutant, and chloride dosage, light, temperature and ultraviolet intensity were considered in the equations for bacterial decay process. The calculated values of the fluid velocities in the two rivers agree well with corresponding measured results, indicating an ideal accuracy of the model. In simulation, the concentration of E. colt in water was assumed to be zero before the accident. The and 1.75 m/s for the Yangtze flow, and the downriver boundary was upriver boundary velocity was -1.35 m/s for the Jialing flow water depth set at 0. Simulation results show that the bacteria are transported downstream along the riverbank. A long and narrow pollutant belt develops at 12 h after the start of the accident ascribed to the quick longitudinal transfer. After the pollution sources are cut off, the pollutant concentration decreases slowly, mostly by advection and diffusion, suggesting inadequate self-purification ability of the rivers and the necessity of effective decontaminating measures in the case of a pollution incident, The model can be a useful tool for understanding the polluting situations of an improper discharge incident and evaluating the effects of decontaminating measures for the water body of the Three Gorges Reservoir.

Characterization and Application of the Makoua Clay in the Chemical and Bacteriological Depollution of Gutter and Well Waters of Brazzaville

In this work, the authors made aquatic filters according to the formulation “clay stabilized at 4% of cement mixed with 4% of kambala sawdust and 10% of white sand” then heated to 1050°C to decontaminate the waters of gutters and wells. The authors carried out geotechnical, geochemical, thermal, infrared spectroscopy, and scanning electron microscopy that analyzed the clay material. Geotechnical analyzes have shown that this material is made up of 22% thin sand, 22% of silt, and 56% of clay with 26 plasticity index. The geochemical analysis showed the presence of trace elements shared out as follows: 3% of alkaline metals, 24% of alkaline earth metals, 46% of transition metals, 10% of metal, 16% of lanthanides, 1% of actinides. The most abundant trace elements are barium (19%), vanadium (12%), chromium (11%) and zinc (9%). The thermal and microscopic analyzes revealed the kaolinitic nature of materials. The chemical depollution studies have shown elimination yields of 50% - 52.38% of sulphates;77.33% - 85.19% of phosphates;34.85% - 88.49% nitrates;91.3 - 100 of sulphides;The removal of bacteriological pollution are 92.8% - 98% of total germs;94% - 97% of total coliform and 95% - 98% of E. coli.

A Study on Water Pollution and Bioremediation in Hedi Reservoir

Statistical work and analysis were made based on data of monitored wa- ter quality data in Hedi Reservoir during 2000-2010 and the results show that the content of nutritive salt was higher and water was moderate or light eutrophication. Based on status quo and practical survey research of the Reservoir, the causes for eutrophication deterioration were analyzed and countermeasures were proposed, providing scientific references for sustainable development of Hedi Reservoir.

Water Pollution Situation and Impacts in Rural China

With the development of national economics, water pollution is becoming a critical problem in rural China. This research presented a brief view of water pollution situation in rural areas of China in terms of water shortage, water-pollutant sources, eutrophication of water bodies and pollution development in temporal scale. Analysis was conducted on the negative effects of water pollution on human health, agricultural plantation and animal husbandry. Subsequently, some suggestions were proposed for wastewater treatment in rural areas.

Effects of reclaimed water irrigation and nitrogen fertilization on the chemical properties and microbial community of soil

The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen（N）levels are important indicators of the effect of reclaimed water irrigation on environment.This study evaluated soil physicochemical properties and microbial community structure in soils irrigated with reclaimed water and receiving varied amounts of N fertilizer.The results indicated that the reclaimed water irrigation increased soil electrical conductivity（EC）and soil water content（SWC）.The N treatment has highly significant effect on the ACE,Chao,Shannon（H）and Coverage indices.Based on a 16S ribosomal RNA（16S rRNA）sequence analysis,the Proteobacteria,Gemmatimonadetes and Bacteroidetes were more abundant in soil irrigated with reclaimed water than in soil irrigated with clean water.Stronger clustering of microbial communities using either clean or reclaimed water for irrigation indicated that the type of irrigation water may have a greater influence on the structure of soil microbial community than N fertilizer treatment.Based on a canonical correspondence analysis（CCA）between the species of soil microbes and the chemical properties of the soil,which indicated that nitrate N（NO3-–-N）and total phosphorus（TP）had significant impact on abundance of Verrucomicrobia and Gemmatimonadetes,meanwhile the p H and organic matter（OM）had impact on abundance of Firmicutes and Actinobacteria significantly.It was beneficial to the improvement of soil bacterial activity and fertility under 120 mg kg^-1 N with reclaimed water irrigation.

Model for water pollution remote sensing based on double scattering and its application in the Zhujiang River outfall

It is a valid route for quantitatively remote sensing on water pollution to build a model according to the physical mechanisms of scattering and absorbing of suspended substance, pollutant, and molecules of water. Remote sensing model for water pollution based on single scattering is simple and easy to be used, but the precision is affected by turbidity of water. The characteristics of the energy composition of multiple scattering, are analyzed and it is proposed that, based on the model of single scattering, if the flux of the second scattering is considered additionally, the precision of the model will be remarkably improved and the calculation is still very simple. The factor of the second scattering is deduced to build a double scattering model, and the practical arithmetic for the calculation of the model is put forward. The result of applying this model in the water area around the Zhujiang(Pearl) River outfall shows that the precision is obviously improved. The result also shows that the seriously polluted water area is distributed in the northeast of Lingding Sea, the Victoria Bay of Hong Kong, and the Shengzhen Bay.

Reservoir operation schemes for water pollution accidents in Yangtze River

After the Three Gorges Reservoir starts running, it can not only take into consideration the interest of departments such as flood control, power generation, water supply, and shipping, but also reduce or eliminate the adverse effects of pollutants by discharge regulation. The evolution of pollutant plumes under different operation schemes of the Three Gorges Reservoir and three kinds of pollutant discharge types were calculated with the MIKE 21 AD software. The feasibility and effectiveness of the reservoir emergency operation when pollution accidents occur were investigated. The results indicate that the emergency operation produces significant effects on the instantaneous discharge type with lesser effects on the constant discharge type, the impact time is shortened, and the concentration of pollutant is reduced. Meanwhile, the results show that the larger the discharge is and the shorter the operation duration is, the more favorable the result is.

Research on mechanism of groundwater pollution from mine water in abandoned mines

In order to understand the mechanism and regularity of the groundwater contamination from mine water of abandoned mines, experiments were conducted on an abandoned coal mine in Fuxin, a representative city with lots of mine water in northeast China. The groundwater pollution from different contaminants of coal-mining voids （total hardness, SO4^2-, CI^- and total Fe） and pollution factors transportation situation in the coal rock were simulated by soil column experiment under the conditions of mine water leaching and main water leaching （similar to rainwater leaching）, and the water-rock interaction mechanism was discussed during mine water infiltration through saturated coal rock by application of principle of mass conservation, based on physical properties of coal rock, as well as monitored chemical composition. The results show that, compared with the clear water leaching process, trends of change in pollutant concentrations presented different characteristics in the mine water leaching process. Groundwater is contaminated by the water rock interactions such as migration ＆ accumulation, adsorption ＆ transformation, dissolution ＆ desorption and ion exchange during the mine water permeation. The experiments also suggest that at first dissolution rate of some kinds of dissoluble salts is high, but it decreases with leaching time, even to zero during both the mine water leaching and main water leaching.

Friction Behaviors of the Hot Filament Chemical Vapor Deposition Diamond Film under Ambient Air and Water Lubricating Conditions

The friction behavior of the hot filament chemical vapor deposition（HFCVD） diamond film plays a critical role on its applications in mechanical fields and largely depends on the environment. Studies on the tribological properties of HFCVD diamond films coated on Co-cemented tungsten carbide （WC-Co） substrates are rarely reported in available literatures, especially in the water lubricating conditions. In this paper, conventional microcrystalline diamond（MCD） and fine-grained diamond（FGD） films are deposited on WC-Co substrates and their friction properties are evaluated on a reciprocating ball-on-plate tribometer, where they are brought to slide against ball-bearing steel and copper balls in dry and water lubricating conditions. Scanning electron microscopy（SEM）, atomic force microscopy（AFM）, surface profilometer and Raman spectroscopy are adopted to characterize as-deposited diamond films; SEM and energy dispersive X-ray（EDX） are used to investigate the worn region on the surfaces of both counterface balls and diamond films. The research results show that the friction coefficient of HFCVD diamond films always starts with a high initial value, and then gradually transits to a relative stable state. For a given counterface and a sliding condition, the FGD film presents lower stable friction coefficients by 0.02-0.03 than MCD film. The transferred materials adhered on sliding interface are supposed to have predominate effect on the friction behaviors of HFCVD diamond films. Furthermore, the effect of water lubricating on reducing friction coefficient is significant. For a given counterpart, the stable friction coefficients of MCD or FGD films reduce by about 0.07-0.08 while sliding in the water lubricating condition, relative to in dry sliding condition. This study is beneficial for widespread applications of HFCVD diamond coated mechanical components and adopting water lubricating system, replacing ofoil lubricating, in a variety of mechanical processing fields to implement the green production process.

Advances of studies on biomonitoring of water pollution in China

The progress of biomonitoring on water pollution in recent years in China has been summarized in this paper.

Electrokinetic chemical characteristics of humic and dannic acids effecting on the natural water and its coagulation

Taking streaming current(SC)as the electrokinetic parameter,this paper demon- strated the electrokinetic chemical characteristics of humic and dannic acids(HA and DA)in sus- pensions including turbid water,coagulated water and HA or DA contained water.Accordingly, the studies were carried out for determining the relationship between streaming current and zeta po- tential ζ(expressed by eleetrophoretie mobility EM)in above water conditions.In addition,the mechanisms of HA effecting on streaming current within or after coagulant addition and the elec- trokinetic detection principles for HA or DA were also investigated on experiments and theoretical analysis.The results indicated that the change of SC like ζ presented meaningful information con- cerning the degree for destabilization of a particulate suspension,and HA or DA in water could re- markably decrease the effect of inorganic coagulant upon streaming current,which is in accordance with their influence on coagulation.

Study on Water Pollution and Control in China

In recent years, water pollution has become increasingly serious in China. Meanwhile, decrease of water bodies in quality, frequent pollution incidents, safety of drinking water and water shortage have become prominent day by day. However, water pollution can not be controlled effectively. To clear underlying reasons for increasingly worsening water environment, the external effects of pollution behavior and fictitious property right of pollution control bodies were analyzed using property right theory, and then internal reasons for serious water pollution were discussed. Fi- nally, control measures of water pollution were put forward.

Analysis of Rural Water Pollution Sources of Lushui Reservoir in Hubei Province

Pollution resulting from increased human activities is threatening the drinking water quality in China.Lushui Reservoir was selected as a typical example to represent polluted drinking water sources with rapid social economic development.This study analyzed the pollution load of Lushui Reservoir from rural areas by estimating the chemical oxygen demand(COD),ammonia nitrogen,total nitrogen and total phosphorus contributed by domestic sewage,agricultural activity,livestock breeding and aquaculture activity.Results show that the annual chemical oxygen demand,ammonia nitrogen,total nitrogen and total phosphorus loads in Lushui Reservoir were 180.44,22.99,33.15,and 3.99 t,respectively.The highest contribution to pollution load in all four aspects is domestic sewage,which was 89%,96%,82%,and 79%,respectively.Therefore,policies for sustainable development in the region should be directed primarily towards a reduction of domestic pollution.

THE STUDY ON NOVEL MICROELECTRODE ARRAY CHIPS FOR THE DETECTION OF HEAVY METALS IN WATER POLLUTION

Qualitative and quantitative analysis of trace heavy metals in aqueous environment are rapidly assuming significance along with the rapid development of industry.In this paper,gold microelectrode array(MEA)plated with mercury film was used for simultaneous voltammetric detection of zinc,cadmium,lead and copper ions in water.The electrochemical behavior and the actual surface area of the MEA were investigated by cyclic voltammetry in K_(3)[Fe(CN)_(6)].Electrochemical impedance spectrum(EIS)was utilized to examine the deposition of mercury on the electrode surface.Based on anodic stripping voltammetry,mercury film
Au MEA was applied to the detection of heavy metals in artificial analyte,where good calibrate linearity was obtained for cadmium,lead and copper ions,but with zinc exhibiting poor linearity.