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Earth Tech for Total Water Management
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《China's Foreign Trade》 1999年第4期36-39,共4页
关键词 Earth Tech for total water Management
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Dynamics of Potable Well Water Quality in Key Mining Chiefdoms in Kono District, Eastern Sierra Leone
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作者 Richard Tamba Simbo Alhaji Brima Gogra +1 位作者 Yahaya Kudus Kawa Juana Paul Moiwo 《Open Journal of Applied Sciences》 2024年第7期1927-1943,共17页
Groundwater is increasingly being used due to its universal availability and generally good quality. However, the risk of contamination of groundwater due to various human activities such as mining is equally increasi... Groundwater is increasingly being used due to its universal availability and generally good quality. However, the risk of contamination of groundwater due to various human activities such as mining is equally increasing across the globe. In this study, the physical parameters of potable well waters in the key mining areas in Nimikoro and Tankoro Chiefdoms in Kono District were analyzed for compliance with drinking water quality standard. To do this, both unpurged and purged well water samples were collected once every month for a period of one year. Some of the well water properties like temperature, Total Dissolved Solids (TDS) and Electrical Conductivity (EC) were measured on site and others determined in the laboratory. The data collected from the laboratory analyses were statistically analyzed in MS Excel, SPSS and ArcGIS environments for quality trends in time-space fabric. The results showed that well water quality in the study area generally fell short of drinking water quality standards of Sierra Leone and WHO. There were high temperature and turbidity during the dry season and then high TDS and EC during the rainy season. Temperature and turbidity also significantly influenced well water quality in the study area, much more than TDS and EC. The implications for drinking water of lower quality than the standard could be huge for the local population and therefore needs the attention of stakeholders in the study area and decision makers in the country. 展开更多
关键词 Temperature total Dissolved Solids TURBIDITY Electrical Conductivity water Quality
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Variability in Quantity and Salinity of Produced Water from an Oil Production in South Kuwait
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作者 Feras Al Salem Thies Thiemann 《Engineering(科研)》 2024年第1期8-23,共16页
Produced water (PW) is the largest waste stream in the oil and gas industry. Water remains trapped for millions of years in the reservoir with oil and gas. When a hydrocarbon reservoir is infiltrated by a production w... Produced water (PW) is the largest waste stream in the oil and gas industry. Water remains trapped for millions of years in the reservoir with oil and gas. When a hydrocarbon reservoir is infiltrated by a production well, the produced fluids commonly contain water. The understanding of this water’s constituents and volumes is vital for the sustainable continuity of production operations, as PW has a number of negative impacts on the infrastructure integrity of the operation. On the other hand, PW can be an alternative source of irrigation water as well as of industrial salt. Interestingly, both the quantity as well as the quality of PW do not remain constant but can vary, both progressively and erratically, even over short periods of time. This paper discusses such a situation of variable PW in an oil and gas operation in the State of Kuwait. 展开更多
关键词 Produced water Oil Wells water-Cut Salinity Fluctuation total Dissolved Solids
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Total Indicative Dose Determination in Water from the North Riviera Well Field of SODECI in Abidjan, Cote d’Ivoire
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作者 Epi Zita Tatiana Kocola Achi Bogbé Douo Louis Huberson Gogon +2 位作者 N’Guessan Guy Léopold Oka Antonin Aka Koua Marie Chantal Kouassi Goffri 《Journal of Environmental Protection》 2023年第12期1006-1015,共10页
The Uranium-238 (<sup>238</sup>U), Thorium-232 (<sup>232</sup>Th) families and Potassium-40 (<sup>40</sup>K) are of terrestrial origin and contribute generally to an individual’s e... The Uranium-238 (<sup>238</sup>U), Thorium-232 (<sup>232</sup>Th) families and Potassium-40 (<sup>40</sup>K) are of terrestrial origin and contribute generally to an individual’s external exposure through our presence in this environment. They also contribute to the internal exposure through the ingestion of products and beverages such as water that are close to the earth. The aim of this work is to determine the committed effective dose or Total Indicative Dose (TID) due to gamma radioactivity of the borehole water from the Nord Riviera (NR) well field operated by the Côte d’Ivoire Water Distribution Company (SODECI) for the supply of drinking water to part of the population of Abidjan. In addition, the populations, with their habits, could use these borehole waters directly as drinking water. To this end, water samples from the seven (07) functional boreholes were collected and analyzed on a gamma spectrometry chain, equipped with an HPGe detector in the laboratory of the Radiation Protection Institute (RPI) of the GHANA Atomic Energy Commission (GAEC). The results of the specific activities of <sup>238</sup>U, <sup>232</sup>Th and <sup>40</sup>K obtained were transcribed into TID. As the natural radioactivity of the borehole water is high [1], the TIDs calculated from the activity results of the natural radionuclides<sup>238</sup>U, <sup>232</sup>Th, and <sup>40</sup>K vary for the seven boreholes from 0.150 to 0.166 mSv/yr with an average of 0.161 ± 0.034 mSv/yr. The TID of the control tower, where the borehole water is mixed and treated for household use, is equal to 0.136 ± 0.03 mSv/yr. The TIDs obtained are therefore all slightly greater than the WHO reference dose value of 0.1 mSv/yr. But all remain below the UNSCEAR reference dose of 0.29 mSv/yr. 展开更多
关键词 North Rivera (NR) Well Field Borehole water Natural Radioactivity Gamma Spectrometry total Indicative Dose Committed Annual Effective Dose
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Use of Total Precipitable Water Classification of A Priori Error and Quality Control in Atmospheric Temperature and Water Vapor Sounding Retrieval 被引量:4
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作者 Eun-Han KWON Elisabeth WEISZ 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第2期263-273,共11页
This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared ... This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared (IR) sounders. Temperature and water vapor profiles are retrieved from Atmospheric InfraRed Sounder (AIRS) radiance measurements by applying a physical iterative method using regression retrieval as the first guess. Based on the dependency of first-guess errors on the degree of atmospheric moistness, the a priori first-guess errors classified by total precipitable water (TPW) are applied in the AIRS physical retrieval procedure. Compared to the retrieval results from a fixed a priori error, boundary layer moisture retrievals appear to be improved via TPW classification of a priori first-guess errors. Six quality control (QC) tests, which check non-converged or bad retrievals, large residuals, high terrain and desert areas, and large temperature and moisture deviations from the first guess regression retrieval, are also applied in the AIRS physical retrievals. Significantly large errors are found for the retrievals rejected by these six QCs, and the retrieval errors are substantially reduced via QC over land, which suggest the usefulness and high impact of the QCs, especially over land. In conclusion, the use of dynamic a priori error information according to atmospheric moistness, and the use of appropriate QCs dealing with the geographical information and the deviation from the first-guess as well as the conventional inverse performance are suggested to improve temperature and moisture retrievals and their applications. 展开更多
关键词 atmospheric sounding AIRS total precipitable water a priori error quality control
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Evaluation of Total Precipitable Water over East Asia from FY-3A/VIRR Infrared Radiances 被引量:1
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作者 ZHENG Jing SHI Chun-Xiang +1 位作者 LU Qi-Feng XIE Zheng-Hui 《Atmospheric and Oceanic Science Letters》 2010年第2期93-99,共7页
Satellite retrieval of atmospheric water vapor is intended to further understand the role played by the energy and water cycle to determine the Earth's weather and climate.The algorithm for operational retrieval o... Satellite retrieval of atmospheric water vapor is intended to further understand the role played by the energy and water cycle to determine the Earth's weather and climate.The algorithm for operational retrieval of total precipitable water (TPW) from the visible and infrared radiometer (VIRR) onboard Fengyun 3A (FY-3A) employs a split window technique for clear sky radiances over land and oceans during both day and night.The retrieved TPW is compared with that from the moderate resolution imaging spectroradiometer (MODIS) onboard the Terra satellite and data from radiosonde observations (RAOB).During the study period,comparisons show that the FY-3A TPW is in general agreement with the gradients and distributions from the Terra TPW.Their zonal mean difference over East Asia is smaller in the daytime than at night,and the main difference occurs in the complex terrain at mid latitude near 30°N.Compared with RAOB,the zonal FY-3A and the Terra TPW have a moist bias at low latitudes and a dry bias at mid and high latitudes;in addition,the FY-3A TPW performs slightly better in zonal mean biases and the diurnal cycle.The temporal variation of the FY-3A and the Terra TPW generally fits the RAOB TPW with the FY-3A more accurate at night while Terra TPW more accurate during the daytime.Comparisons of correlations,root mean square differences and standard deviations indicate that the FY-3A TPW series is more consistent with the RAOB TPW at selected stations.As a result,the FY-3A TPW has some advantages over East Asia in both spatial and temporal dimensions. 展开更多
关键词 nFY-3A/VIRR total precipitable water split window technique evaluatio.
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Total Energy Expenditure of 16 Chinese Young Men Measured by the Doubly Labeled Water Method 被引量:4
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作者 ZHUO Qin SUN Rui +5 位作者 GOU Ling Yan PIAO Jian Hua LIU Jian Min TIAN Yuan ZHANG Yu Hui YANG Xiao Guang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第6期413-420,共8页
Objective Doubly labeled water (DLW) method is the gold standard for measuring total energy expenditure (TEE). We used this method to measure TEE in Chinese young men. Methods Sixteen healthy young men age 23±... Objective Doubly labeled water (DLW) method is the gold standard for measuring total energy expenditure (TEE). We used this method to measure TEE in Chinese young men. Methods Sixteen healthy young men age 23±1 recruited. TEE was measured by the DLW method, by indirect calorimetry. We also conducted 24-h estimate energy requirements of the subjects. years with body mass index 22.0±1.4 kg/m2 were and basal energy expenditure (BEE) was determined activity, energy balance and factorial approach to Results TEE of subjects by DLW method was 9.45±0.57 M J/day (2258±180 kcal/day). The 24-h activity was 10.80±0.33 M J/day (2582±136 kcal/day). The energy requirement, derived from energy balance observations, was 9.93±1.32 M J/day (2373±315 kcal/day). The BEE of 6.65±0.28 M J/day (1589±67 kcal/day), calculated by the adjusted Schofield equation, was significantly higher (P〈O.O01) than that measured by indirect calorimetry, 5.99-±0.66 M J/day (1433-±158 kcal/day). The TEE derived from the factorial approach was 10.31-±0.43 M J/day (2463±104 kcal/day). Conclusion The TEE of Chinese young men measured by the DLW method was about 10% lower than the current recommended nutrient intake (RNI), suggesting that the RNI for Chinese men maybe overestimated. Further studies are warranted to determine the value of the estimated energy requirement. 展开更多
关键词 Doubly labeled water total energy expenditure Recommended nutrient intakes Estimatedenergy requirement Chinese young men
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Effects of cloud,atmospheric water vapor,and dust on photosynthetically active radiation and total solar radiation in a Mongolian grassland 被引量:1
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作者 Tserenpurev BAT-OYUN Masato SHINODA Mitsuru TSUBOn 《Journal of Arid Land》 SCIE 2012年第4期349-356,共8页
Photosynthetically active radiation (PAR) is an important input parameter for estimating plant produc- tivity due to its key role in the growth and development of plants. However, a worldwide routine network for sys... Photosynthetically active radiation (PAR) is an important input parameter for estimating plant produc- tivity due to its key role in the growth and development of plants. However, a worldwide routine network for sys- tematic PAR measurements is not yet established, and PAR is often calculated as a constant fraction of total solar radiation (SR). Although the ratio of PAR to SR (PAR/SR) has been reported from many places, few studies have been performed for dry regions. The present study was therefore carried out in an arid region of Mongolia to obtain PAP-JSR and examine its dependency on sky clearness (the clearness index), water vapor in the atmosphere and aeolian dust. Continuous measurements of PAR and SR were taken every one second using quantum and pyranometer sensors, respectively, and the readings were averaged and recorded at intervals of 30 minutes for a period of 12 months. The lowest monthly mean daily PAR/SR occurred in April (0.420), while the highest ratio was observed in July (0.459). Mean daily PAR/SR during plant growing season (May-August) was estimated to be 0.442, which could be useful for modeling plant productivity in the study area. The annual mean daily PAR/SR (0.435) was lower than the values reported in many previous studies. This difference could be explained with the regional variation in climate: i.e. drier climatic condition in the study area. PAR/SR was negatively correlated with the clearness index (r= -0.36, P〈0.001), but positively with atmospheric water vapor pressure (r=0.47, P〈0.001). The average PAR/SR was significantly lower (P=0.02) on the dusty days compared to the non-dust days. Water vapor in the atmosphere was shown to be the strongest factor in the variation of PAR/SR. This is the first study examining PAR/SR under a semi-arid condition in Mongolia. 展开更多
关键词 clearness index dust storm photosynthetically active radiation total solar radiation water vapor pressure
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Harmoniousness analysis of total amount control of water use
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作者 Qian-qi YIN Guo-hua FANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期49-59,共11页
Based on the fundamental principles of total amount control of water use, the harmony theory was used in this study to develop a concept of the degree of harmony of total amount control of water use. Based on this con... Based on the fundamental principles of total amount control of water use, the harmony theory was used in this study to develop a concept of the degree of harmony of total amount control of water use. Based on this concept, the harmoniousness of total amount control of water use was analyzed in terms of the supply and demand of water resources, water resources management, water use benefits, and water-saving level. An evaluation index system of the degree of harmony of total amount control of water use was established, and a method for calculation of the degree of harmony of total amount control of water use was developed based on the analytic hierarchy process (AHP) and fuzzy comprehensive analysis (FCA) methods. The new evaluation index system was applied to a certain area in Jiangsu Province, China. The degree of harmony of total amount control of water use over this area was calculated for different years. Results indicate that the evaluation index system and calculation method proposed in this study are feasible, and such a harmoniousness analysis can provide scientific references for the strict water resources management system that will be implemented in China in the near future. 展开更多
关键词 total amount control of water usel degree of harmony evaluation index system quantification method analytic hierarchy process method fuzzy comprehensive analysis method
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Horizontal distribution of Changjiang Diluted Water in summer inferred from total suspended sediment in the Yellow Sea and East China Sea
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作者 LEE Dong-Kyu KWON Jae-Il SON Seung Hyun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第12期44-50,共7页
During the summer in the Yellow Sea and East China Sea, the resuspension of the bottom sediment is obstructed by strong stratification and, as a result, the concentration of total suspended sediment(TSS) can be used... During the summer in the Yellow Sea and East China Sea, the resuspension of the bottom sediment is obstructed by strong stratification and, as a result, the concentration of total suspended sediment(TSS) can be used as an excellent tracer for Changjiang Diluted Water(CDW). To analyze the spatial and temporal variations of the CDW distribution, the monthly mean TSS from Moderate Resolution Imaging Spectroradiometer(MODIS) ocean color data are constructed and are converted to salinity using the relationship between salinity observed from AQUARIUS and TSS. The process produces the detailed horizontal distribution of salinity with very high resolution(1 km). From monthly mean salinity map from 2002 to 2012 in July and August, the expansion patterns of CDW are analyzed. The southerly wind in July and southeasterly wind in August transport the CDW eastward and northeastward, respectively. It is found that the yearly variation of the expansion of CDW toward the southern sea area of Korea is mostly due to the variation of southerly wind and the fluctuations of fresh water discharge into the Changjiang estuary show relatively little impact on the eastward extend of CDW. When 11-year mean(from2002 to 2012) salinity map in August is compared with World Ocean Atlas 2013, it is revealed that wind in August strengthened six times from 1994 and it causes the expansion of CDW extended 150 km further eastward. 展开更多
关键词 Yellow and East China Seas Changjiang diluted water total suspended sediment MODIS
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Evaluation of Total Hydrocarbons Levels and Traces Metals in Water and Sediment from Main Outfall Drain in Al-Nassiriya City/Southern Iraq 被引量:1
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作者 Afrah A. Maktoof Basim Y. ALKhafaji Zahraa Z. Al-janabi 《Natural Resources》 2014年第13期795-803,共9页
This study was conducted during Dec2011-Nov2012 on three stations located in the south sector of Main Outfall Drain (MOD) River. Station 1 was near Al-Holandee Bridge which was the general carriage way in the center o... This study was conducted during Dec2011-Nov2012 on three stations located in the south sector of Main Outfall Drain (MOD) River. Station 1 was near Al-Holandee Bridge which was the general carriage way in the center of Al-Nassiriya city, station 2 was 20 km far from the first station, while station 3 was in the beginning of the new branch. This study reveals the Seasonal Variation of Total petroleum hydrocarbons (TPHs) in both surface waters, sediment and it is related with trace metals nickel and vanadium in water (dissolved, particulate) and sediment (residual and exchangeable) phases. Also, the study shows the relationships between the concentration of Ni and V with Total Organic Carbon (TOC%) in the sediment. 展开更多
关键词 total Petroleum Hydrocarbons Traces METALS water Sediment MAIN OUTFALL DRAIN
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Evaluation of the Pathogen Detect<sup>®</sup>System and Anthracene-Based Enzyme Substrates for the Detection and Differentiation of <i>E. coli</i>and Total Coliforms in Water Samples
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作者 Neville Hewage Mazen Saleh 《Journal of Water Resource and Protection》 2015年第9期689-701,共13页
Indirect detection of Escherichia coli and total coliforms can be based on the enzymatic activities of β-glucuronidase (β-glu) and β-galactosidase (β-gal). These enzymes utilize the substrates anthracene-β-d-gluc... Indirect detection of Escherichia coli and total coliforms can be based on the enzymatic activities of β-glucuronidase (β-glu) and β-galactosidase (β-gal). These enzymes utilize the substrates anthracene-β-d-glucuronide and pyrene d-galactopyranoside, respectively. Substrate cleavage by the enzyme releases the soluble fluorescent molecules 2-hydroxyanthracene and 1-hydroxypyrene, which can then be detected by a fluorometer. The Pathogen Detect? system is an automated portable unit that can measure fluorescent enzyme products. In this report, we investigated the utility of the Pathogen Detect? system for potential automation of water quality monitoring. The PDS unit has the ability to detect E. coli, mean 14.7 h at a standard deviation of 1.5, when the sample mean is 9.1 cells in 100 mL with a standard deviation of 12.6. Similarly, total coliforms may be detected at mean 14.7 h with a standard deviation of 1.4 when the sample mean is 59.6 cells in 100 mL, with a standard deviation of 144.5. The PDS unit has the ability to detect single cells of either total coliforms or E. coli in 100 mL water sample within 18 hours. Turbidity and color of water samples have no impact on the detection of E. coli and total coliforms. 展开更多
关键词 ESCHERICHIA COLI total COLIFORMS ENZYME Substrate water Quality
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Effects of Conservation Methods of Water Samples on Determination of Total Phosphorus
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作者 Zhang Yan Wang Dong +4 位作者 Xu Min Xie Yangcun Luo Yueping Tian Yun Luo Fang 《Meteorological and Environmental Research》 CAS 2014年第1期1-3,11,共4页
Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temper... Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temperature and time. The results showed that SS concentration in water and natural sedimentation time had the greatest impact on the determination of total phosphorus, while the influence of methods of adding conserving agent, conservation temperature and time was relatively smaller. TP concentration in water samples conserved irregularly was higher than the standard value due to the existence of SS and microorganisms in water, and the deviation became larger with the increase of SS concentration in water. In addition, quality control measures and matters needing attention during the conservation process of water samples were put forward to improve the accuracy of TP concentration. 展开更多
关键词 water samples total phosphorus CONSERVATION Quality control China
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An Optimal Model of the Total Amount Allocation for Surface Water Pollutants Based on the Principles of Equity and Efficiency
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作者 GAO Zi-ting PANG Tian-yi +4 位作者 ZHAO Wen-jin MA Duan-chao GAO Lei ZHANG Yu-nan LI Yu 《Meteorological and Environmental Research》 2012年第10期27-30,35,共5页
The control of total water pollutant amount is an effective method to improve quality of the groundwater, but how to allocate the total amount is an important and difficult work. In this paper, equity and efficiency w... The control of total water pollutant amount is an effective method to improve quality of the groundwater, but how to allocate the total amount is an important and difficult work. In this paper, equity and efficiency were bases of the total amount allocation. Took total amount allocation of the surface water pollutant in a car manufacturing group as an example, the current emissions and unit of output value as the bases for cluster analysis, the target unit was divided into "key reduction unit" and "concern reduction unit". Then, allocation scheme of the total amount was prepared. This model for research and improvement of the feasibility for total pollutant amount allocation technique has certain reference value. 展开更多
关键词 total amount allocation water contaminant Optimal model China
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Experimental study on total dissolved gas supersaturation in water 被引量:1
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作者 Lu QU Ran LI +2 位作者 Jia LI Ke-feng LI Lin WANG 《Water Science and Engineering》 EI CAS 2011年第4期396-404,共9页
More and more high dams have been constructed and operated in China. The total dissolved gas (TDG) supersaturation caused by dam discharge leads to gas bubble disease or even death of fish, Through a series of exper... More and more high dams have been constructed and operated in China. The total dissolved gas (TDG) supersaturation caused by dam discharge leads to gas bubble disease or even death of fish, Through a series of experiments, the conditions and requirements of supersaturated TDG generation were examined in this study. The results show that pressure (water depth), aeration, and bubble dissolution time are required for supersaturated TDG generation, and the air-water contact area and turbulence intensity are the main factors that affect the generation rate of supersaturated TDG. The TDG supersaturation levels can be reduced by discharging water to shallow shoals downstream of the dam or using negative pressure pipelines. Furthermore, the TDG supersaturation levels in stilling basins have no direct relationship with those in reservoirs. These results are of great importance for further research on the prediction of supersaturated TDG generation caused by dam discharge and aquatic protection. 展开更多
关键词 total dissolved gas supersaturation dissolved gas in water experimental study dam discharge
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渗透各向异性土层中考虑挡墙厚度的基坑稳态渗流解析解 被引量:1
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作者 余俊 李东凯 +2 位作者 和振 张志中 张鑫全 《铁道学报》 EI CAS CSCD 北大核心 2024年第5期142-151,共10页
本文对考虑厚度挡墙支护下渗透各向异性土层中基坑的二维稳态渗流进行了解析研究。根据对称性取基坑半截面,将周围土层划分为5个规则区域,采用坐标变换将渗透各向异性土层转换成等效各向同性土层,对各区域利用叠加法和分离变量法推导得... 本文对考虑厚度挡墙支护下渗透各向异性土层中基坑的二维稳态渗流进行了解析研究。根据对称性取基坑半截面,将周围土层划分为5个规则区域,采用坐标变换将渗透各向异性土层转换成等效各向同性土层,对各区域利用叠加法和分离变量法推导得到二维稳态渗流场、挡墙上水压力以及坑底出逸比降的显式解析解。对比保角变换和积分变换方法,本文解渗流场计算结果连续且无奇异点,且基坑水头和挡墙两侧水压力分布情况与数值软件分析一致性较好,说明本文解析解的正确性和优越性。本文解与不同计算方法得到的挡墙水压力结果对比分析发现,挡墙厚度d、竖直与水平向渗透系数比α对挡墙上水压力的影响不可忽略。分析α、d对挡墙底部水压力及出逸比降的影响,随着α和d的增大,基坑外侧挡墙底部水压力增大,基坑内侧挡墙底部水压力减小;随着α和d的逐渐减小,坑底出逸比降不断增大;当α和d较小时,考虑一维渗流情况得到的出逸比降安全性较低,且随着α和d的减小与本文解析解差距越来越大。 展开更多
关键词 二维稳态渗流 渗透各向异性 显式解析解 考虑厚度的挡墙 总水头分布 出逸比降 水压力
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Evaluation of media for simultaneous enumeration of total coliform and Escherichia coli in drinking water supplies by membrane filtration techniques 被引量:1
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作者 WANG Dunling FIESSEL Wanda 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第3期273-277,共5页
This study evaluated three different dehydrated media for simultaneous detection and enumeration of total coliform (TC) and Escherichia coil in drinking water samples with a standard membrane filtration procedure. T... This study evaluated three different dehydrated media for simultaneous detection and enumeration of total coliform (TC) and Escherichia coil in drinking water samples with a standard membrane filtration procedure. The experiment indicated that the differential coliform agar (DCA) medium was the most effective among the tested media in enumerating TC and E. coil, without the need for extensive accompanying confirmation tests. The results for DCA medium were highly reproducible for both TC and E. coil with standard deviation of 6.0 and 6.1, respectively. A high agreement (82%) was found between DCA and m-Endo media on 152 drinking water samples in terms of TC positive. The DCA medium also reduced concealment of background bacteria. 展开更多
关键词 drinking water differential coliform agar (DCA) total coliform (TC) E. coli membrane filtration (MF)
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育肥猪智能饮水碗设计与性能测试
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作者 龙定彪 唐明凤 +4 位作者 胡彬 王浩 于洲 潘学民 蒲施桦 《农业工程学报》 EI CAS CSCD 北大核心 2024年第17期250-256,共7页
饮水量及饮水的质量是影响猪只生长和健康的重要因素,研制新型猪只节水清洁型智能饮水设备对猪舍管理和提高动物福利具有重要意义。该研究对传统碗式饮水器进行了改进,研制了一种猪只智能节水型饮水碗,探究了智能饮水碗在猪只生产性能... 饮水量及饮水的质量是影响猪只生长和健康的重要因素,研制新型猪只节水清洁型智能饮水设备对猪舍管理和提高动物福利具有重要意义。该研究对传统碗式饮水器进行了改进,研制了一种猪只智能节水型饮水碗,探究了智能饮水碗在猪只生产性能、用水量、饮水行为和碗内饮用水卫生指标方面的应用效果。试验选取100头体质量为(85.87±15.80)kg的育肥猪,随机分为2个处理组,饮水设备分别采用传统饮水碗和智能饮水碗,每个处理组5个重复,每个重复10头猪,试验期为35 d。结果表明,2种饮水碗对育肥猪的生产性能(日增质量、日采食质量和料肉比)和饮水行为(饮水次数、饮水时长)无显著影响。传统饮水碗组和智能饮水碗组育肥猪的日均用水量分别为(11.14±0.46)、(10.05±0.46)L/d,两者存在极显著差异(P<0.01);浪费水量分别为(0.89±0.13)、(0.25±0.11)L/d,两者存在极显著差异(P<0.01);育肥猪使用智能饮水碗的用水浪费率相比传统饮水碗降低了60.9%~79.5%。传统饮水碗组和智能饮水碗组育肥猪的碗内余水总大肠菌群分别为(83.00±3.46)、(68.33±4.04)MPN/100 mL,两者存在极显著差异(P<0.01)。育肥猪使用智能饮水碗的碗内余水总大肠菌群与传统饮水碗相比降低了16.3%~19.2%。该智能饮水碗能有效保障猪只饮水健康和生长需求,减少猪只饮水浪费,降低碗内余水总大肠菌群数量,提高动物福利水平。研究可为养殖场节水减排提供理论依据及技术支撑。 展开更多
关键词 育肥猪 节水 智能饮水碗 总大肠菌群 浪费水量
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南水北调中线受水区全要素水资源绿色效率及节水减排潜力
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作者 薛宝琪 范红艳 《地域研究与开发》 CSSCI 北大核心 2024年第5期138-144,共7页
采用非径向、非角度SBM-DEA模型测算2015—2021年南水北调中线受水区20个城市全要素水资源绿色效率,探究其时空演变规律,并分析各市节水减排潜力。结果表明:受水区全要素水资源绿色效率总体呈现以京津冀、郑州两大都市圈为核心向外围逐... 采用非径向、非角度SBM-DEA模型测算2015—2021年南水北调中线受水区20个城市全要素水资源绿色效率,探究其时空演变规律,并分析各市节水减排潜力。结果表明:受水区全要素水资源绿色效率总体呈现以京津冀、郑州两大都市圈为核心向外围逐渐递减的“核心-外围”空间结构模式以及全要素水资源绿色效率由高到低依次为京津、河南、河北的空间分异规律;2015—2021年受水区全要素水资源绿色效率总体呈波动上升趋势,但仍处于较低水平,仅实现了最优效率的70%~85%;不同城市节水减排潜力差异显著,空间上呈现“南高北低、西高东低”的分布格局。 展开更多
关键词 SBM-DEA模型 全要素水资源绿色效率 节水潜力 减排潜力 南水北调中线
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宿迁经济技术开发区需水预测及用水总量控制指标核定研究
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作者 王明明 方琼 +1 位作者 侯坦 卞锦宇 《江苏水利》 2024年第3期69-72,共4页
通过分析宿迁经济技术开发区水资源开发利用现状,根据区域人口、经济发展指标,对规划年进行需水预测。依据区域用水总量和效率控制指标、区域地下水取用水总量和水位管控要求等,结合区域功能定位、产业布局,核定了用水总量控制指标,为... 通过分析宿迁经济技术开发区水资源开发利用现状,根据区域人口、经济发展指标,对规划年进行需水预测。依据区域用水总量和效率控制指标、区域地下水取用水总量和水位管控要求等,结合区域功能定位、产业布局,核定了用水总量控制指标,为进一步简化建设项目水资源论证审批程序以及提高审批效能等提供参考。 展开更多
关键词 需水预测 用水总量 控制指标
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