Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin...Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin of Northeast Qinghai-Tibet Plateau, where such geological hazards as soil erosion, landslides collapse and debris flows are widespread due to the highly erodible loess. Salinized loess soil collected from the test site was desalinized through salt-leaching in the laboratory. The desalinized and oven-dried loess samples were also artificially moisturized and salinized in order to examine how soil salinity affects its shear strength at different moisture levels. Soil samples prepared in different ways(moisturizing, salt-leaching, and salinized) were measured to determine soil cohesion and internal friction angle. The results show that salt-leaching up to 18 rounds almost completely removed the salt content and considerably changed the physical components of loess, but the soil type remained unchanged. As salt content increases from 0.00% to 12.00%, both the cohesion and internal friction angle exhibit an initial decrease and then increase with salt content. As moisture content is 12.00%, the salt content threshold value for both cohesion and internal friction angle is identified as 3.00%. As the moisture content rises to 16.0% and 20.00%, the salt content threshold value for cohesion is still 6.00%, but 3.00% for internal friction angle. At these thresholds soil shear strength is the lowest, below which it is inversely related to soil salinity. Beyond the thresholds, however, the relationship is positive. Dissimilar to salinity, soil moisture content exerts an adverse effect on shear strength of loess. The findings of this study can provide a valuable guidance on stabilizing the engineering properties of salinized loess to prevent slope failures during heavy rainfall events.展开更多
The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in th...The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in the area. The basin is underlain by Albian sediments, essentially shales, in the lowlands, which were affected by low-grade metamorphism that had produced slates. The highlands comprise basic intrusives from episodes of magmatism and metallic ore mineralisation. Injection of brines into the aquifer system and low, seasonal aquifer recharge from rainfall results in poor water quality in the area. The study analyzes the geochemical distribution in water sources in the area and identifies sources of pollutants to guide the better choice of portable water. Results of hydrogeochemical analysis of both surface and groundwater from the communities were compared with World Health Organization to identify portable water locations in the area. While the salt lake at Okposi is the main source of brine intrusion in the study area, the Pb/Zn mine at Ishiagu is the main source of mine-water pollution in the study area. Most chemical parameters, (especially Cl<sup>-</sup>, Na<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup>, SO<sub>4</sub><sup>2-</sup>, HCO<sub>3</sub><sup>-</sup>) maintain high concentrations within the salt lake area, with the values declining away from the salt lake. The main anthropogenic source of pollution in the area, especially at Ishiagu, is the indiscriminate surface mining of lead-zinc without proposer waste management practices. Possible sourcing for portable water in the study area includes a deep borehole at Ishiagu, away from lead-zinc intrusives. At the Okposi axis, searching for portable water in boreholes should target shallower aquifers that do not communicate with the deeper-seated brine zones, likewise targeting zones farther away from these brine-invaded areas. A controlled pumping rate could potentially ensure that the cone of depression was not low enough to reach the brine zone 展开更多
The aridity, population growth, agriculture and industrial activities threaten the water resources in the United Arab Emirates (UAE). In UAE, groundwater quantity is reduced and its quality is also deteriorated due to...The aridity, population growth, agriculture and industrial activities threaten the water resources in the United Arab Emirates (UAE). In UAE, groundwater quantity is reduced and its quality is also deteriorated due to the scanty of rainfall and over pumping for different uses. The deficit of groundwater is met by desalinated water and reused of treated wastewater. Agricultural activities have negative impacts on water resources and this causes reduction of groundwater quality as the agriculture the main land use in the UAE and it accounts for more than 70% of groundwater use. The treated wastewater is an alternative source for agricultural activities. To improve the current water situation, a national water resources strategy has been prepared and imple-mented to assist in achieve this target and maintain the country’s water security. This paper intends to give an overview of water resources in the UAE with emphasis on challenges facing the management of these resources.展开更多
The solar desalinator is a low cost installation and operation equipment that can contribute to tackling the problem of water shortages in the world.Because of the importance of this equipment,the present work has the...The solar desalinator is a low cost installation and operation equipment that can contribute to tackling the problem of water shortages in the world.Because of the importance of this equipment,the present work has the objective to quantify the relation of the temperature of the water with the production of the equipment.For this,a compact desalinator with glass cover in square pyramidal form and a heating system controlled by a logic programmer was built.As a result,it was verified the efficiency of the logic controller as an auxiliary tool for experimental work and the relationship between temperature ranges and desalination production.展开更多
To evaluate the potential risk of arteriosclerosis caused by desalinated seawater, Wistar rats were provided desalinated seawater over a 1-year period, and blood samples were collected at 0, 90, 180, and 360 days. Blo...To evaluate the potential risk of arteriosclerosis caused by desalinated seawater, Wistar rats were provided desalinated seawater over a 1-year period, and blood samples were collected at 0, 90, 180, and 360 days. Blood calcium, magnesium, and arteriosclerosis-related indicators were investigated. Female rats treated with desalinated seawater for 180 days showed lower magnesium levels than the control rats (P 〈 0.05). The calcium and magnesium levels in female rats and the magnesium level in male rats were lower than the levels in the controls, following treatment with desalinated seawater for 360 days (P 〈 0.05). Blood levels of arteriosclerosis-related lipid peroxidation indicators and C-reactive protein (CRP) in the treatment group did not differ from those in the controls. The levels of lipid peroxidation indicators and CRP in rats were not significantly affected by drinking desalinated seawater, and no increase in risk of arteriosclerosis was observed.展开更多
Household desalinated drinking water samples collected from outdoor points and from indoor consumption points at 99 locations representing more than 95% of the residential areas in Kuwait were analyzed for 25 trace el...Household desalinated drinking water samples collected from outdoor points and from indoor consumption points at 99 locations representing more than 95% of the residential areas in Kuwait were analyzed for 25 trace elements and water quality parameters. Only Al, Cr, Co, Cu, Fe, Pb, Ni, and Zn were found to be over-represented at the consumption point compared with the outdoor point, with wide variations among the sampling locations and elements. The highest increases were observed for Fe (135%) and Zn (123%), followed by Pb (69%), Co (58%), Cu (42%), Cr (31%), and Al (30%), and the lowest increase was observed for Ni (19%). In most cases, the increases in Cu, Fe, and Zn were inversely proportional to the conductivity and directly proportional to the Cl– concentration. In the outdoor samples, only Fe exceeded the US-EPA guideline (in 3% of the outdoor samples taken), whereas Fe, Pb, and Ni exceeded the US-EPA and WHO guidelines in 8.5%, 0.3%, and 1% of the indoor consumption point samples, respectively. Thus, leaching from household utilities may cause health concerns for consumers of drinking water in Kuwait. The increases in Fe were the highest in the summer (240%), and in this regard, Fe exhibited the greatest difference between summer and winter (the increase was 139% higher in the summer). The results of the present study may be useful for water production authorities and consumers in Kuwait and suggest the use of alternative new pipes with more resistant internal coatings and connecting techniques.展开更多
To this day, only two types of solar power plants have been proposed and built: high temperature thermal solar one and photovoltaic one. It is here proposed a new type of solar thermal plant using glass-top flat surfa...To this day, only two types of solar power plants have been proposed and built: high temperature thermal solar one and photovoltaic one. It is here proposed a new type of solar thermal plant using glass-top flat surface solar collectors, so working at low temperature (i.e., below 100°C). This power plant is aimed at warm countries, i.e., the ones mainly located between -40° and 40° latitude, having available space along their coast. This land based plant, to install on the seashore, is technologically similar to the one used for OTEC (Ocean Thermal Energy Conversion). This plant, apart from supplying electricity with a much better thermodynamic efficiency than OTEC plants, has the main advantage of providing desalinated water for drinking and irrigation. This plant is designed to generate electricity (and desalinated water) night and day and all year round, by means of hot water storage, with just a variation of the power delivered depending on the season.展开更多
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 41572306, 41162010)Natural Science Foundation of Qinghai Province (Grant No.2014ZJ-906)+3 种基金Hundred Talents Program in Chinese Academy of Sciences (Grant No. Y110091025)Scientific and Technologic Support Plan of Qinghai Province (2015-SF-117)Changjiang Scholar Program and Innovative Research Team Building, MOE Grant Number (IRT_17R62)the 111 Project (Grant No. D18013)
文摘Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin of Northeast Qinghai-Tibet Plateau, where such geological hazards as soil erosion, landslides collapse and debris flows are widespread due to the highly erodible loess. Salinized loess soil collected from the test site was desalinized through salt-leaching in the laboratory. The desalinized and oven-dried loess samples were also artificially moisturized and salinized in order to examine how soil salinity affects its shear strength at different moisture levels. Soil samples prepared in different ways(moisturizing, salt-leaching, and salinized) were measured to determine soil cohesion and internal friction angle. The results show that salt-leaching up to 18 rounds almost completely removed the salt content and considerably changed the physical components of loess, but the soil type remained unchanged. As salt content increases from 0.00% to 12.00%, both the cohesion and internal friction angle exhibit an initial decrease and then increase with salt content. As moisture content is 12.00%, the salt content threshold value for both cohesion and internal friction angle is identified as 3.00%. As the moisture content rises to 16.0% and 20.00%, the salt content threshold value for cohesion is still 6.00%, but 3.00% for internal friction angle. At these thresholds soil shear strength is the lowest, below which it is inversely related to soil salinity. Beyond the thresholds, however, the relationship is positive. Dissimilar to salinity, soil moisture content exerts an adverse effect on shear strength of loess. The findings of this study can provide a valuable guidance on stabilizing the engineering properties of salinized loess to prevent slope failures during heavy rainfall events.
文摘The study investigates the hydrogeochemical characteristics of some towns in the Abakaliki Basin, comprising, Ishiagu, Aka Eze, Amaseri, Afikpo and Okposi communities, with the aim of sourcing for portable water in the area. The basin is underlain by Albian sediments, essentially shales, in the lowlands, which were affected by low-grade metamorphism that had produced slates. The highlands comprise basic intrusives from episodes of magmatism and metallic ore mineralisation. Injection of brines into the aquifer system and low, seasonal aquifer recharge from rainfall results in poor water quality in the area. The study analyzes the geochemical distribution in water sources in the area and identifies sources of pollutants to guide the better choice of portable water. Results of hydrogeochemical analysis of both surface and groundwater from the communities were compared with World Health Organization to identify portable water locations in the area. While the salt lake at Okposi is the main source of brine intrusion in the study area, the Pb/Zn mine at Ishiagu is the main source of mine-water pollution in the study area. Most chemical parameters, (especially Cl<sup>-</sup>, Na<sup>+</sup>, Ca<sup>2+</sup>, Mg<sup>2+</sup>, SO<sub>4</sub><sup>2-</sup>, HCO<sub>3</sub><sup>-</sup>) maintain high concentrations within the salt lake area, with the values declining away from the salt lake. The main anthropogenic source of pollution in the area, especially at Ishiagu, is the indiscriminate surface mining of lead-zinc without proposer waste management practices. Possible sourcing for portable water in the study area includes a deep borehole at Ishiagu, away from lead-zinc intrusives. At the Okposi axis, searching for portable water in boreholes should target shallower aquifers that do not communicate with the deeper-seated brine zones, likewise targeting zones farther away from these brine-invaded areas. A controlled pumping rate could potentially ensure that the cone of depression was not low enough to reach the brine zone
文摘The aridity, population growth, agriculture and industrial activities threaten the water resources in the United Arab Emirates (UAE). In UAE, groundwater quantity is reduced and its quality is also deteriorated due to the scanty of rainfall and over pumping for different uses. The deficit of groundwater is met by desalinated water and reused of treated wastewater. Agricultural activities have negative impacts on water resources and this causes reduction of groundwater quality as the agriculture the main land use in the UAE and it accounts for more than 70% of groundwater use. The treated wastewater is an alternative source for agricultural activities. To improve the current water situation, a national water resources strategy has been prepared and imple-mented to assist in achieve this target and maintain the country’s water security. This paper intends to give an overview of water resources in the UAE with emphasis on challenges facing the management of these resources.
文摘The solar desalinator is a low cost installation and operation equipment that can contribute to tackling the problem of water shortages in the world.Because of the importance of this equipment,the present work has the objective to quantify the relation of the temperature of the water with the production of the equipment.For this,a compact desalinator with glass cover in square pyramidal form and a heating system controlled by a logic programmer was built.As a result,it was verified the efficiency of the logic controller as an auxiliary tool for experimental work and the relationship between temperature ranges and desalination production.
基金supported by the Public Science and Technology Research Funds Projects of Ocean for the study of ‘Effects of desalinated water on human and animal health’ from the project ‘Reverse osmosis of desalinated seawater and the development of testing desalinated water’
文摘To evaluate the potential risk of arteriosclerosis caused by desalinated seawater, Wistar rats were provided desalinated seawater over a 1-year period, and blood samples were collected at 0, 90, 180, and 360 days. Blood calcium, magnesium, and arteriosclerosis-related indicators were investigated. Female rats treated with desalinated seawater for 180 days showed lower magnesium levels than the control rats (P 〈 0.05). The calcium and magnesium levels in female rats and the magnesium level in male rats were lower than the levels in the controls, following treatment with desalinated seawater for 360 days (P 〈 0.05). Blood levels of arteriosclerosis-related lipid peroxidation indicators and C-reactive protein (CRP) in the treatment group did not differ from those in the controls. The levels of lipid peroxidation indicators and CRP in rats were not significantly affected by drinking desalinated seawater, and no increase in risk of arteriosclerosis was observed.
文摘Household desalinated drinking water samples collected from outdoor points and from indoor consumption points at 99 locations representing more than 95% of the residential areas in Kuwait were analyzed for 25 trace elements and water quality parameters. Only Al, Cr, Co, Cu, Fe, Pb, Ni, and Zn were found to be over-represented at the consumption point compared with the outdoor point, with wide variations among the sampling locations and elements. The highest increases were observed for Fe (135%) and Zn (123%), followed by Pb (69%), Co (58%), Cu (42%), Cr (31%), and Al (30%), and the lowest increase was observed for Ni (19%). In most cases, the increases in Cu, Fe, and Zn were inversely proportional to the conductivity and directly proportional to the Cl– concentration. In the outdoor samples, only Fe exceeded the US-EPA guideline (in 3% of the outdoor samples taken), whereas Fe, Pb, and Ni exceeded the US-EPA and WHO guidelines in 8.5%, 0.3%, and 1% of the indoor consumption point samples, respectively. Thus, leaching from household utilities may cause health concerns for consumers of drinking water in Kuwait. The increases in Fe were the highest in the summer (240%), and in this regard, Fe exhibited the greatest difference between summer and winter (the increase was 139% higher in the summer). The results of the present study may be useful for water production authorities and consumers in Kuwait and suggest the use of alternative new pipes with more resistant internal coatings and connecting techniques.
文摘To this day, only two types of solar power plants have been proposed and built: high temperature thermal solar one and photovoltaic one. It is here proposed a new type of solar thermal plant using glass-top flat surface solar collectors, so working at low temperature (i.e., below 100°C). This power plant is aimed at warm countries, i.e., the ones mainly located between -40° and 40° latitude, having available space along their coast. This land based plant, to install on the seashore, is technologically similar to the one used for OTEC (Ocean Thermal Energy Conversion). This plant, apart from supplying electricity with a much better thermodynamic efficiency than OTEC plants, has the main advantage of providing desalinated water for drinking and irrigation. This plant is designed to generate electricity (and desalinated water) night and day and all year round, by means of hot water storage, with just a variation of the power delivered depending on the season.