Samples of fog water collected in the area of Guangzhou during February, March and April of 2005 are used in this work to study the chemical composition of fog water in polluting fog there. Three typical episodes of p...Samples of fog water collected in the area of Guangzhou during February, March and April of 2005 are used in this work to study the chemical composition of fog water in polluting fog there. Three typical episodes of polluting fog are analyzed in terms of ionic concentration and their possible sources. It is found that the concentration of various ions in fog water is much higher than those in rainwater. Fog not only blocks visual range but contains liquid particles that result in high degree of pollution and are very harmful to human health. SO4= is the anion with the highest concentration in fog water, followed by NO3-. For the cation, Ca++ and NH4+ are the highest in concentration. It is then known that rainwater is more acidic than fog water, indicating that ionic concentration of fog water is much higher than that of rainwater, but there are much more buffering materials in fog water, like NH4+ and Ca++. There is significant enrichment of Ca++, SO4=, and Mg++ in fog water. In the Guangzhou area, fog water from polluting fog is mainly influenced continental environment and human activity. The episodes of serious fog pollution during the time have immediate relationships with the presence of abundant water vapor and large amount of polluting aerosol particles.展开更多
Superfluous arsenic in drinking water can do harm to human health. In this paper, a broad overview of the available technologies for arsenic removal has been presented on the basis of literature survey. The main treat...Superfluous arsenic in drinking water can do harm to human health. In this paper, a broad overview of the available technologies for arsenic removal has been presented on the basis of literature survey. The main treatment methods included coagulation-sedimentation, adsorption separation and ion exchange, membrane technique, which have both advantages and disadvantages. It concluded that the selection of treatment process should be site specific and prevailing conditions and no process can serve the purpose under diverse conditions as each technology has its own limitations. In order to gain good results, some methods should be improved.展开更多
The pH values of soils collected from 30 different districts of Al-Madinah Al-Munawarah province were measured using an Electric pH meter. The pH values revealed （27%） a slight to （60%） medium alkalinity ranged be...The pH values of soils collected from 30 different districts of Al-Madinah Al-Munawarah province were measured using an Electric pH meter. The pH values revealed （27%） a slight to （60%） medium alkalinity ranged between： 7.17-9.45 （pH 8.13 ± 0.13） The alkalinity is attributed to scanty rainfall and deep underground waters as well as deposition of high air pollution contents at Al-Madinah Al-Munawarah. Such soil alkalinity is not optimum to growth of arable/lea-grassland but only for limited cultivation i.e. date palms in comparison with Northwestern and Southwestern sectors of KSA. It is recommended to carry out similar soil evaluation of other parts of KSA involving more measurements i.e. ionic concentration, nutrient levels, micro-flora and to laundry these lands to lower soil＇spHs and to increase its fertility.展开更多
Filters filled with a micelle-clay complex mixed with sand were employed to investigate their purification capability of tertiary treated wastewater with loose UF-membranes. The UF membrane was hollow fiber with a mol...Filters filled with a micelle-clay complex mixed with sand were employed to investigate their purification capability of tertiary treated wastewater with loose UF-membranes. The UF membrane was hollow fiber with a molecular weight cutoff of 100 kD. The complex was prepared from the organic cation octadecyltrimethylammonium （ODTMA） and the negatively charged clay-mineral, montmoriIIonite. This complex has a very large surface area, which includes large hydrophobic domains and is positively charged, about half of the cation exchange capacity of the clay. Two sets of filtration experiments were carried out at flow rates of 1.2 and 50 mL/min, which correspond to flow velocities of 3.7 and 153 cm/h, respectively. In the first case, after a passage of 1 L, the turbidity, total suspended solids （TSS）, fecal coliforms （FC）, and total coliforms （TC） were reduced to zero from 14 NTU, 6 ppm, 350 and 10,000 counts per 100 mL, respectively. In the second case, the numbers of FC and TC were reduced from 50,000/100 mL to zero after the passage of 14 L. The values of COD and BOD were reduced several-fold. The conclusion is that the incorporation of micelle-clay filters in the sewage treatment system with loose tertiary capability is promising and warrants larger scale experiments for optimization of the overall system.展开更多
基金Natural Science Foundation of China (40375002, 40418008, 40775011, U0733004)Project 863 (2006AA06A306, 2006AA06A308)+3 种基金National Basic Research Program of China (973 Program):2005CB422207Natural Science Foundation of Guangdong Province (033029)Project of Key Scientific Research of Guangdong Province (2004A30401002, 2005B32601011)Project of Applied Fundamental Research of Guangzhou (2004J1-0021)
文摘Samples of fog water collected in the area of Guangzhou during February, March and April of 2005 are used in this work to study the chemical composition of fog water in polluting fog there. Three typical episodes of polluting fog are analyzed in terms of ionic concentration and their possible sources. It is found that the concentration of various ions in fog water is much higher than those in rainwater. Fog not only blocks visual range but contains liquid particles that result in high degree of pollution and are very harmful to human health. SO4= is the anion with the highest concentration in fog water, followed by NO3-. For the cation, Ca++ and NH4+ are the highest in concentration. It is then known that rainwater is more acidic than fog water, indicating that ionic concentration of fog water is much higher than that of rainwater, but there are much more buffering materials in fog water, like NH4+ and Ca++. There is significant enrichment of Ca++, SO4=, and Mg++ in fog water. In the Guangzhou area, fog water from polluting fog is mainly influenced continental environment and human activity. The episodes of serious fog pollution during the time have immediate relationships with the presence of abundant water vapor and large amount of polluting aerosol particles.
文摘Superfluous arsenic in drinking water can do harm to human health. In this paper, a broad overview of the available technologies for arsenic removal has been presented on the basis of literature survey. The main treatment methods included coagulation-sedimentation, adsorption separation and ion exchange, membrane technique, which have both advantages and disadvantages. It concluded that the selection of treatment process should be site specific and prevailing conditions and no process can serve the purpose under diverse conditions as each technology has its own limitations. In order to gain good results, some methods should be improved.
文摘The pH values of soils collected from 30 different districts of Al-Madinah Al-Munawarah province were measured using an Electric pH meter. The pH values revealed （27%） a slight to （60%） medium alkalinity ranged between： 7.17-9.45 （pH 8.13 ± 0.13） The alkalinity is attributed to scanty rainfall and deep underground waters as well as deposition of high air pollution contents at Al-Madinah Al-Munawarah. Such soil alkalinity is not optimum to growth of arable/lea-grassland but only for limited cultivation i.e. date palms in comparison with Northwestern and Southwestern sectors of KSA. It is recommended to carry out similar soil evaluation of other parts of KSA involving more measurements i.e. ionic concentration, nutrient levels, micro-flora and to laundry these lands to lower soil＇spHs and to increase its fertility.
文摘Filters filled with a micelle-clay complex mixed with sand were employed to investigate their purification capability of tertiary treated wastewater with loose UF-membranes. The UF membrane was hollow fiber with a molecular weight cutoff of 100 kD. The complex was prepared from the organic cation octadecyltrimethylammonium （ODTMA） and the negatively charged clay-mineral, montmoriIIonite. This complex has a very large surface area, which includes large hydrophobic domains and is positively charged, about half of the cation exchange capacity of the clay. Two sets of filtration experiments were carried out at flow rates of 1.2 and 50 mL/min, which correspond to flow velocities of 3.7 and 153 cm/h, respectively. In the first case, after a passage of 1 L, the turbidity, total suspended solids （TSS）, fecal coliforms （FC）, and total coliforms （TC） were reduced to zero from 14 NTU, 6 ppm, 350 and 10,000 counts per 100 mL, respectively. In the second case, the numbers of FC and TC were reduced from 50,000/100 mL to zero after the passage of 14 L. The values of COD and BOD were reduced several-fold. The conclusion is that the incorporation of micelle-clay filters in the sewage treatment system with loose tertiary capability is promising and warrants larger scale experiments for optimization of the overall system.
