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The Economics of Competing Water Uses under a FERC Licensing Agreement: Estimation of Property Value, Recreation, and Hydroelectric Impacts
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作者 Matthew Bingham Jason Kinnell 《Journal of Water Resource and Protection》 CAS 2024年第6期414-428,共15页
Reservoirs provide a variety of services with economic values across multiple sectors. As demands for reservoir services continue to grow and precipitation patterns evolve, it becomes ever more important to consider t... Reservoirs provide a variety of services with economic values across multiple sectors. As demands for reservoir services continue to grow and precipitation patterns evolve, it becomes ever more important to consider the integrated suite of values and tradeoffs that attend changes in water uses and availability. Section 316 (b) of the Clean Water Act requires that owners of certain water cooled power plants evaluate technologies and operational measures that can reduce their impacts to aquatic organisms. The studies must discuss the social costs and benefits of alternative technologies including cooling towers (79 Fed. Reg. 158, 48300 - 48439). Cooling towers achieve their effect through evaporation. This manuscript estimates the property value, recreation, and hydroelectric generation impacts that could result from the evaporative water loss associated with installing cooling towers at the McGuire Nuclear Generating Station (McGuire) located on Lake Norman, North Carolina. Although this study specifically evaluates the effects of evaporative water loss from cooling towers, its methods are applicable to estimating the economic benefits and costs of a new water user or reduced water input in any complex reservoir system that supports steam electric generation, hydroelectric generation, residential properties, recreation, irrigation, and municipal water use. 展开更多
关键词 property Value FERC Hydroelectric RECREATION water Levels
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Effect of different process conditions on the physicochemical and antimicrobial properties of plasma-activated water 被引量:1
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作者 蔡志成 王佳媚 +4 位作者 王媛媛 桑晓涵 曾丽仙 邓文韬 章建浩 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第12期63-71,共9页
The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed tha... The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed that increasing the processing time and power,and decreasing generated water volume,could cause an increase in the redox potential,conductivity,and temperature of PAW,and a decrease in its pH.A slower dissipation of the reactive oxygen and nitrogen species in PAW was found on storage at 4℃in a sealed conical flask than on storage at room temperature.The inactivation ability of plasma-activated lactic acid(LA)to Listeria monocytogenes(L.monocytogenes)and Pseudomonas aeruginosa(P.aeruginosa)was higher than that of PAW or LA alone under the same experimental conditions.The results of this study may provide theoretical information for the application of PAW as a potential antimicrobial agent in the future. 展开更多
关键词 plasma activated water physicochemical properties treatment conditions disinfection effect
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Effect of Water Absorption on the Mechanical Property and Failure Mechanism of Hollow Glass Microspheres Composite Epoxy Resin Solid Buoyancy Materials
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作者 DING Yue ZHAI Gang-jun +2 位作者 MA Zhe WEI Zi-hao LI Xin 《China Ocean Engineering》 SCIE EI CSCD 2023年第5期876-884,共9页
To study the water absorption of hollow glass microspheres(HGMs)composite epoxy resin solid buoyancy materials in the marine environment and its effect on the mechanical properties,the water absorption was measured by... To study the water absorption of hollow glass microspheres(HGMs)composite epoxy resin solid buoyancy materials in the marine environment and its effect on the mechanical properties,the water absorption was measured by immersing the material in distilled water for 36 days at ambient temperature and fitted to Fick’s second law.The strength of materials before and after water absorption were tested by uniaxial experiments,and the effects of the filling ratio and water absorption on the mechanical properties of the materials were analyzed and explained.Finally,the failure modes and mechanism of the hollow glass microspheres composite material were explicated from the microscopic level by scanning electron microscope(SEM).This research will help solve the problems of solid buoyancy materials in ocean engineering applications. 展开更多
关键词 solid buoyancy material water absorption mechanical property failure mechanism scanning electron microscope
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A“bricks-and-mortar”structured graphene oxide/polyvinyl alcohol coating:Enhanced water interfacial lubrication and durability
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作者 Hanglin LI Lin DING +5 位作者 Jingchun ZHANG Zhaoyang GUO Yazhuo SHANG Honglai LIU Xiangqiong ZENG Jiusheng LI 《Friction》 SCIE EI CAS CSCD 2024年第12期2657-2678,共22页
Coatings serve as ideal protective films for mechanical systems,providing dependable as well as efficient lubrication because of their unique structure along with outstanding tribological characteristics.Inspired by ... Coatings serve as ideal protective films for mechanical systems,providing dependable as well as efficient lubrication because of their unique structure along with outstanding tribological characteristics.Inspired by the“bricks-and-mortar”structure,we prepared layered graphene oxide(GO)composite finishes strengthened with polyvinyl alcohol(PVA)and borax.Our study demonstrates that the tribological properties of the GO-based coating on 304 stainless steel(SS304)are potentially greatly affected through PVA,GO,and annealing.By optimizing the composition,we achieved the PVA_(40 wt%)/GO_(0.01 wt%)/borax composite coating,which exhibited the lowest average coefficient of friction(COF)of 0.021±0.003(a 97.86%reduction compared to control SS304)with minimal wear and abrasion even in a water environment.We found that the enhanced mechanical characteristics as well as elastic recovery within the coating were attributed to the hydrogen bonds and cross-linking between PVA and borax,which led to stress distribution.Reduced friction was further aided by the formation of a hydrated layer at the friction interface.As a result,the coating demonstrated remarkable durability,maintaining a low COF during long sliding distances(576 m,28,800 cycles,significantly longer than previously reported)without breaking. 展开更多
关键词 graphene oxide COATING water lubrication anti-wear properties DURABILITY
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Distribution of modified Circumpolar Deep Water and its threat in Vincennes Bay,East Antarctica
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作者 Wenjun YE Lingqiao CHENG +2 位作者 Yujiro KITADE Song HU Juncheng ZUO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1399-1414,共16页
The Antarctic Bottom Water formation site Vincennes Bay,East Antarctica is experiencing a substantial intrusion of modified Circumpolar Deep Water(mCDW),which may inhibit the formation of Dense Shelf Water(DSW)and dri... The Antarctic Bottom Water formation site Vincennes Bay,East Antarctica is experiencing a substantial intrusion of modified Circumpolar Deep Water(mCDW),which may inhibit the formation of Dense Shelf Water(DSW)and drive basal melting of the ice shelves.Based on hydrographic data obtained from March to November in 2012,we evaluated the spatial spread of mCDW over the continental shelf region of Vincennes Bay and the associated temporal evolution of water properties,as well as the sea ice formation effect on water column in the coastal polynya.Results show that two branches of mCDW occupied the deep layers of the continental shelf,distinguished by the potential density(smaller than 27.8 kg/m^(3) or not)when potential temperatureθ=0.5°C in theθ-salinity space.The warmer and less dense branch observed on the east plateau,accessed the eastern ice shelves in the coastal polynya to drive basal melting of ice shelves.In contrast,the other colder and denser branch in the mid-depression reached the western Underwood Ice Shelf.DSW formation was detectable in the coastal polynya during September-November,proving the occurrence of deep convection.Surface heat loss and brine rejection during the intensive sea ice formation contributed to the destratification of the water column in the coastal polynya.It was estimated that at least 1.11±0.79 TW heat carried by mCDW into the inner part of the polynya. 展开更多
关键词 modified circumpolar deep water evolution of water properties coastal polynya ice shelf Vincennes Bay
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Experimental investigation into the salinity effect on the physicomechanical properties of carbonate saline soil
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作者 Jiejie Shen Qing Wang +3 位作者 Yating Chen Xuefei Zhang Yan Han Yaowu Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1883-1895,共13页
For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety performance.This stu... For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety performance.This study examines the Atterberg limits,shear strength,and compressibility of carbonate saline soil samples with different NaHCO3 contents in Northeast China.The mechanism underlying the influence of salt content on soil macroscopic properties was investigated based on a volumetric flask test,a mercury intrusion porosimetry(MIP)test,and a scanning electron microscopic(SEM)test.The results demonstrated that when NaHCO3 contents were lower than the threshold value of 1.5%,the bound water film adsorbed on the surface of clay particles thickened continuously,and correspondingly,the Atterberg limits and plasticity index increased rapidly as the increase of sodium ion content.Meanwhile,the bonding force between particles was weakened,the dispersion of large aggregates was enhanced,and the soil structure became looser.Macroscopically,the compressibility increased and the shear strength(mainly cohesion)decreased by 28.64%.However,when the NaHCO3 content exceeded the threshold value of 1.5%,the salt gradually approached solubility and filled the pores between particles in the form of crystals,resulting in a decrease in soil porosity.The cementation effect generated by salt crystals increased the bonding force between soil particles,leading to a decrease in plasticity index and an improvement in soil mechanical properties.Moreover,this work provides valuable suggestions and theoretical guidance for the scientific utilization of carbonate saline soil in backfill engineering projects. 展开更多
关键词 Carbonate saline soil Salt content Physicomechanical properties Bound water MICROSTRUCTURE
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Aircraft Observation and Simulation of the Supercooled Liquid Water Layer in a Warm Conveyor Belt over North China
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作者 Jiefan YANG Fei YAN +3 位作者 Hengchi LEI Shuo JIA Xiaobo DONG Xiangfeng HU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期529-544,共16页
This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer... This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer of warm conveyor belts(WCBs).Based on the aircraft data,we found a fine vertical structure within clouds in the WCB and highlighted a 1-2 km thin supercooled liquid water layer with a maximum Liquid Water Content(LWC) exceeding0.5 g kg^(-1) during the vertical aircraft observation.Although the main features of thermodynamic profiles were essentially captured by both modeling schemes,the microphysical quantities exhibited large diversity with different microphysics schemes.The conventional Morrison two-moment scheme showed remarkable agreement with in-situ observations,both in terms of the thermodynamic structure and the supercooled liquid water layer.However,the microphysical structure of the WCB clouds,in terms of LWC and IWC,was not apparent in HUJI fast bin scheme.To reduce such uncertainty,future work may focus on improving the representation of microphysics in bin schemes with in-situ data and using similar assumptions for all schemes to isolate the impact of physics. 展开更多
关键词 warm conveyor belt Microphysical properties supercooled liquid water microphysics schemes
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Time-dependent model for two-phase flow in ultra-high water-cut reservoirs:Time-varying permeability and relative permeability
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作者 Shao-Chun Wang Na Zhang +3 位作者 Zhi-Hao Tang Xue-Fei Zou Qian Sun Wei Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2536-2553,共18页
For the ultra-high water-cut reservoirs,after long-term water injection exploitation,the physical properties of the reservoir change and the heterogeneity of the reservoir becomes increasingly severe,which further agg... For the ultra-high water-cut reservoirs,after long-term water injection exploitation,the physical properties of the reservoir change and the heterogeneity of the reservoir becomes increasingly severe,which further aggravates the spatial difference of the flow field.In this study,the displacement experiments were employed to investigate the variations in core permeability,porosity,and relative permeability after a large amount of water injection.A relative permeability endpoint model was proposed by utilizing the alternating conditional expectation(ACE)transformation to describe the variation in relative permeability based on the experimental data.Based on the time dependent models for permeability and relative permeability,the traditional oil-water two-phase model was improved and discretized using the mimetic finite difference method(MFD).The two cases were launched to confirm the validation of the proposed model.The impact of time-varying physical features on reservoir production performance was studied in a real water flooding reservoir.The experimental results indicate that the overall relative permeability curve shifts to the right as water injection increases.This shift corresponds to a transition towards a more hydrophilic wettability and a decrease in residual oil saturation.The endpoint model demonstrates excellent accuracy and can be applied to time-varying simulations of reservoir physics.The impact of variations in permeability and relative permeability on the reservoir production performance yields two distinct outcomes.The time-varying permeability of the reservoir results in intensified water channeling and poor development effects.On the other hand,the time-varying relative permeability enhances the oil phase seepage capacity,facilitating oil displacement.The comprehensive time-varying behavior is the result of the combined influence of these two parameters,which closely resemble the actual conditions observed in oil field exploitation.The time-varying simulation technique of reservoir physical properties proposed in this paper can continuously and stably characterize the dynamic changes of reservoir physical properties during water drive development.This approach ensures the reliability of the simulation results regarding residual oil distribution. 展开更多
关键词 Mimetic finite difference water flooding reservoir Time-varying physical properties Numerical simulation
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Unraveling the hydraulic properties of loess for landslide prediction:A study on variations in loess landslides in Lanzhou,Dingxi,and Tianshui,China
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作者 Gao-chao Lin Wei Liu Xing Su 《China Geology》 CAS CSCD 2024年第2期291-302,共12页
Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re sidents.The involvement of water repre sents a critical factor in induci... Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re sidents.The involvement of water repre sents a critical factor in inducing loess landslides.This study focuses on three neighboring cities sequentially situated on the Loess Plateau along the direction of aeolian deposition of loess,namely Lanzhou,Dingxi,and Tianshui,which are densely populated and prone to landslide disasters.The variations in hydraulic properties,including water retention capacity and permeability,are investigated through Soil Water Characteristic Curve(SWCC)test and hydraulic conductivity test.The experimental findings revealed that Tianshui loess exhibited the highest water retention capacity,followed by Dingxi loess,while Lanzhou loess demonstrated the lowest water retention capacity.Contrastingly,the results for the saturated permeability coefficient were found to be the opposite:Tianshui loess showed the lowest permeability,whereas Lanzhou loess displayed the highest permeability.These results are supported and analyzed by scanning electron microscopy(SEM)observation.In addition,the water retention capacity is mathematically expressed using the van Genuchten model and extended to predict unsaturated hydraulic properties of loess.The experimental results exhibit a strong accordance with one another and align with the regional distribution patterns of disasters. 展开更多
关键词 LOESS LANDSLIDE Hydraulic properties water retention capacity and permeability Soil water Characteristic Curve(SWCC) Hydraulic conductivity Van Genuchten model Hydrogeological engineering Geological hazards prevention engineering
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Viscoelasto-plastic properties of deep hard rocks under water environment 被引量:5
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作者 曹平 万琳辉 +2 位作者 汪亦显 黄永恒 张向阳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2711-2718,共8页
Using a circular incremental step load and unload method, a set of rheological experiments were performed to study the viscoelasto-plastic properties of amphibolite in Jinchuan No.2 diggings under different environmen... Using a circular incremental step load and unload method, a set of rheological experiments were performed to study the viscoelasto-plastic properties of amphibolite in Jinchuan No.2 diggings under different environments. Based on the scientific analysis on rheological experimental data, the viscoelasto-plastic properties of amphibolite under different environments were studied. The results show that the instantaneous elastic modulus and viscoplastic properties of amphibolite are affected little, the viscoelastic properties of amphibolite are significantly affected. Based on the experimental results and characteristics of recovered rock specimen, a generalized Kelvin model was chosen to simulate rheological properties of amphibolites and key parameters were obtained. It is found that the creep deformation modulus E1 is significantly influenced by the water, while the instant elastic modulus E2 is not significantly affected. The discreteness of the viscosity coefficient η is large, the influence of water on η is not clear and needs to be further studied. 展开更多
关键词 water viscoelasto-plastic property circular incremental step load and unload generalized Kelvin model
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Effect of Water Control before Transplanting and Rooting Powder Treatment on Tobacco Seedling Quality and Physiological Properties at Green Stage
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作者 陈平平 宋怀远 +4 位作者 周亚哲 杨梦慧 裴晓东 易镇邪 屠乃美 《Agricultural Science & Technology》 CAS 2016年第10期2283-2286,2368,共5页
Cultivating strong seedlings is an important guarantee for the production of high-quality flue-cured tobacco, while there are many disadvantages in tobacco floating system that is commonly adopted in China. To improve... Cultivating strong seedlings is an important guarantee for the production of high-quality flue-cured tobacco, while there are many disadvantages in tobacco floating system that is commonly adopted in China. To improve the tobacco floating system, with Xiangyan No.3 as experimental material, the effects of water control before transplanting and rooting powder treatment on tobacco seedling quality and physiological properties at green stage were investigated. The results showed that: (1) water control showed small influence on tobacco seedling quality, while rooting powder treatment and water control + rooting powder treatment showed great influence on tobacco seedling quality, mainly represented by reduced plant height, thickened stem and increased dry matter accumulative amount; (2) water control before transplanting and rooting powder treatment all improved leaf chlorophyll content and root vigor of tobacco seedlings, and the effect of water control + rooting powder treatment was best, followed by rooting powder treatment and water control; (3) all treatments increased the nitrate reductase and invertase activity, and reduced the MDA content of tobacco seedlings, and the effect of water control + rooting powder treatment was best, followed by rooting powder treatment and water control. Mean- while, the treatment effect 10 d before the transplanting was better than that 5 d before the transplanting. In overall, the improvement effects of water control 10 d before transplanting + rooting powder treatment on tobacco seedling quality and physiological properties at green stage were the best. 展开更多
关键词 Flue-cured tobacco Tobacco seedling Green stage water control Rooting powder Physiological properties
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Detection Research and Control Evaluation of Seam Roof Water Yield Property in Yulin-Hengshan Southern Mining Area 被引量:22
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作者 方刚 《矿业安全与环保》 北大核心 2017年第5期98-102,共5页
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Influences of water treatment agents on oil-water interfacial properties of oilfield produced water 被引量:9
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作者 Guo Jixiang Cao Jingjing +1 位作者 Li Mingyuan Xia Haiying 《Petroleum Science》 SCIE CAS CSCD 2013年第3期415-420,共6页
The emulsion stability of oilfield produced water is related to the oil-water interfacial film strength and the zeta potential of the oil droplets. We investigated the effects of water treatment agents (corrosion inh... The emulsion stability of oilfield produced water is related to the oil-water interfacial film strength and the zeta potential of the oil droplets. We investigated the effects of water treatment agents (corrosion inhibitor SL-2, scale inhibitor HEDP, germicide 1227, and flocculant polyaluminium chloride PAC) on the stability of oilfield produced water. The influence of these treatment agents on oil-water interfacial properties and the mechanism of these agents acting on the oilfield produced water were studied by measuring the interfacial shear viscosity, interfacial tension and zeta electric potential. The results indicated that the scale inhibitor HEDP could increase the oil-water interfacial film strength, and it could also increase the absolute value of the zeta potential of oil droplets. HEDP played an important role in the stability of the emulsion. Polyaluminum chloride (PAC) reduced the stability of the emulsion by considerably decreasing the absolute value of the zeta potential of oil droplets. Corrosion inhibitor SL-2 and germicide 1227 could decrease the oil-water interfacial tension, whereas they had little influence on oil-water interfacial shear viscosity and oil-water interfacial electricity properties. 展开更多
关键词 water treatment agents oil-water interracial properties emulsion stability oilfield produced water
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Effects of water intrusion and loading rate on mechanical properties of and crack propagation in coal–rock combinations 被引量:10
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作者 陈田 姚强岭 +4 位作者 卫斐 种照辉 周健 王常彬 李静 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期423-431,共9页
Tackling the problems of underground water storage in collieries in arid regions requires knowledge of the effect of water intrusion and loading rate on the mechanical properties of and crack development in coal–rock... Tackling the problems of underground water storage in collieries in arid regions requires knowledge of the effect of water intrusion and loading rate on the mechanical properties of and crack development in coal–rock combinations. Fifty-four coal–rock combinations were prepared and split equally into groups containing different moisture contents(dry, natural moisture and saturated) to conduct acoustic emission testing under uniaxial compression with loading rates ranging from 0.1 mm/min to 0.6 mm/min. The results show that the peak stress and strength-softening modulus, elastic modulus, strain-softening modulus, and post-peak modulus partly decrease with increasing moisture content and loading rate. In contrast, peak strain increases with increasing moisture content and fluctuates with rising loading rate. More significantly, the relationship between stiffness and stress, combined with accumulated counts of acoustic emission, can be used to precisely predict all phases of crack propagation. This is helpful in studying the impact of moisture content and loading rate on crack propagation and accurately calculating mechanical properties. We also determined that the stress thresholds of crack closure, crack initiation, and crack damage do not vary with changes of moisture content and loading rate, constituting 15.22%, 32.20%, and 80.98% of peak stress, respectively. These outcomes assist in developing approaches to water storage in coal mines, determining the necessary width of waterproof coal–rock pillars, and methods of supporting water-enriched roadways, while also advances understanding the mechanical properties of coal–rock combinations and laws of crack propagation. 展开更多
关键词 water intrusion loading rate mechanical properties coal-rock combination crack propagation stress threshold
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Effects of reclaimed water irrigation and nitrogen fertilization on the chemical properties and microbial community of soil 被引量:11
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作者 GUO Wei Mathias N Andersen +4 位作者 QI Xue-bin LI Ping LI Zhong-yang FAN Xiang-yang ZHOU Yuan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第3期679-690,共12页
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... 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. 展开更多
关键词 reclaimed water NITROGEN soil chemical properties 16S rRNA sequence soil microbe community
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INFLUENCE OF SILOXANE CO-SEGMENT LENGTH AND CONTENT OF WATERBORNE POLYSILOXANE-URETHANE COPOLYMERS ON THEIR WATER RESISTANCE,THERMAL STABILITY AND MECHANICAL PROPERTIES 被引量:7
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作者 郑强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第2期219-229,共11页
A series of stable waterborne polysiloxaneurethane (WPSUR) dispersions were prepared using amino-terminated polydimethylsiloxane (NS), dimethylolpropionic acid (DMPA), castor oil, polypropylene glycol and toluen... A series of stable waterborne polysiloxaneurethane (WPSUR) dispersions were prepared using amino-terminated polydimethylsiloxane (NS), dimethylolpropionic acid (DMPA), castor oil, polypropylene glycol and toluene diisocyanate. Meanwhile, NS with different molecular weights was synthesized and used as the soft co-segment. Effects of types and contents of soft co-segments as well as chain extenders on the thermal degradation and stability for WPSUR films were examined. Results reveal that WPSUR films exhibit excellent water resistance and mechanical properties as compared with pure polyurethane (PU) films, and the NS soft co-segment possesses a remarkable effect on the second stage (stage Ⅱ), while the content of the hard segment is propitious to the initial stage (stage Ⅰ). Moreover, the highest temperature of stage Ⅱ (T2m) for WPSUR films using NS as soft co-segment is 413℃, approximately being 30℃ higher than that of those typical PUs using HDA and APDMS as the chain extenders, respectively. 展开更多
关键词 waterBORNE POLYSILOXANE Polyurethane Castor oil Thermal properties water resistance.
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Influence of tourist disturbance on soil properties, plant communities, and surface water quality in the Tianchi scenic area of Xinjiang, China 被引量:3
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作者 WEN Bin ZHANG Xiaolei +2 位作者 YANG Zhaoping XIONG Heigang QIU Yang 《Journal of Arid Land》 SCIE CSCD 2016年第2期304-313,共10页
The impact of tourist disturbance on the environment has become a focal issue of environmental science, ecology, and travel management studies. To assess the influence of tourist disturbance on soils and plants in the... The impact of tourist disturbance on the environment has become a focal issue of environmental science, ecology, and travel management studies. To assess the influence of tourist disturbance on soils and plants in the Tianchi scenic area of Xinjiang, China, we compared soil properties and plant community characteristics at 0, 5, 10, and 20 m from the tourist trail within areas at three different altitudes, where the intensities of tourist disturbance are distinct. Surface water quality was also studied at three different levels relative to the Tianchi Lake. The results showed that tourist disturbance significantly increased soil pH within 10 m from the trail and soil bulk density on the edge of the trail, but significantly reduced soil organic matter and total nitrogen contents within 5 m from the trail. The number of tree seedlings on the edge of the trail and the shrub coverage and height of herbaceous plants within 5 m from the trail significantly decreased due to tourist disturbance. Changes in herbaceous plant diversity differed by soil zones. In the high altitude region, tourist disturbance led to a remarkable increase in the herbaceous plant diversity on the edge of the trail, while in the low altitude region, tourist disturbance had a low impact on the diversity of herbaceous plants. In addition, tourist activities polluted the surface water, significantly reducing water quality. Thus, current tourist activities have a significant negative impact on the ecological environment in the Tianchi scenic area. 展开更多
关键词 tourist disturbance soil properties plant communities water quality Tianchi scenic area
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Study on coagulation property of metal-polysilicate coagulants in low turbidity water treatment 被引量:9
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作者 杨海燕 崔福义 +1 位作者 赵庆良 马超 《Journal of Zhejiang University Science》 EI CSCD 2004年第6期721-726,共6页
In order to remove the low turbidity present in surface water, a novel metal-polysilicate coagulant was used to treat the raw water taken from Tanjiang River in Guangdong Province. This study on the effects of Al/Fe ... In order to remove the low turbidity present in surface water, a novel metal-polysilicate coagulant was used to treat the raw water taken from Tanjiang River in Guangdong Province. This study on the effects of Al/Fe molar ratio on the performance of a complex compound formed by polysilicic acid, aluminium and ferric salt (PAFS) showed that PAFS with Al/Fe ratio of 10:3 seemed to have the best coagulation performance in removing turbidity and color. Experimental results showed that under the conditions of polymerization time of 15 d, sedimentation time of 12 min, and pH of 6?8, PAFS with Al/Fe molar ratio of 10:3 had the best coagulation efficiency and lowest residual Al concentration. The turbid- ity decreased from 23.8 NTU to 3.23 NTU and the residual Al concentration was only 0.165 mg/L in the product water. It could be speculated that colloidal impurities and particulate Al were removed by adsorption bridging and electrical neu- tralization of long chain inorganic polymer coagulants. 展开更多
关键词 Potable water treatment Metal-polysilicate coagulant Coagulation property Residual aluminum
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Effect of Hydration Aging and Water Binder Ratio on Microstructure and Mechanical Properties of Sprayed Concrete 被引量:4
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作者 牛荻涛 王家滨 WANG Yan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第4期745-751,共7页
In order to study the durability of sprayed concrete (shotcrete), effects of different hydration aging and water-binder ratio (w/b) on the microstructure of cement paste and basic mechanical properties of test spe... In order to study the durability of sprayed concrete (shotcrete), effects of different hydration aging and water-binder ratio (w/b) on the microstructure of cement paste and basic mechanical properties of test specimens were investigated. The phase composition, mass percentage of ettringite and portland in hydration production and microstructure were characterized by X-ray diffraction (XRD), thermo gravimetry-differential scanning calorimetry (TG-DSC) and scanning electron microscopy (SEM), respectively. The experimental results showed that changes in phase composition was more significant than those of water-binder ratio. With hydration aging and water-binder ratio increased, the mass percentage of ettringite and portland was decreased from 4.42%, 1.49% to 3.31%, 1.35%, respectively and the microstructure of paste was significantly compacted. Likewise, the mechanical properties including cubic compressive strength and splitting tensile strength were rised obviously. 展开更多
关键词 hydration aging water binder ratio (w/b) sprayed concrete(shortcrete) microstructuremechanical properties
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Fluorescence Quenching of a Novel Eu(Ⅲ) Coordination Compound for the Detection of Trace Amounts of Water: Synthesis, Structure and Photoluminescent Property 被引量:2
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作者 王秋华 吴叶文 宋莉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1341-1347,共7页
A novel luminescent coordination compound Eu(TTA)3(DEDAF)(1, TTA = 1,1,1-trifluoro-3-(2-thenoyl)acetone, DEDAF = 9,9-diethyl-4,5-diazafluoren) has been synthesized and fully characterized by infrared spectrum,... A novel luminescent coordination compound Eu(TTA)3(DEDAF)(1, TTA = 1,1,1-trifluoro-3-(2-thenoyl)acetone, DEDAF = 9,9-diethyl-4,5-diazafluoren) has been synthesized and fully characterized by infrared spectrum, elemental analysis, UV-vis spectrum, etc. X-ray single-crystal diffraction analysis reveals that compound 1 shows a mononuclear structure with the europium atom in coordinating to one DAF and three TTA ligands. The mononuclear structure units are assembled into a 3-D polymer by hydrogen bonds and π-π interactions. Photoluminescent property of 1 was investigated in detail at room temperature. Complex 1 emits strong red luminescence. However, it could be quenched even by small amount of water. The fluorescence intensity at 614 nm decreases linearly with the water content increasing(vol% in acetonitrile) in the range of 0.025~0.2% under 278 nm excitation. Thermogravimetric analysis has also been studied, which demonstrates good thermal stability of 1. 展开更多
关键词 europium coordination compound 9 9-diethyl-4 5-diazafluoren photoluminescent property fluorescence quenching water detection
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