Fresh Drinking Water Research Articles

Ground water toxicity due to fluoride contamination in Southwestern Lahore, Punjab, Pakistan

Abstract The prevalence of dental/bone deformities provides motivation for studying the distribution, severity and sources of the Fluoride (F−1). The ground water samples (n = 77) were collected, from the districts of Lahore and Kasur of approximately 750 km2 area. The water was analyzed for fluoride (F−), pH, electric conductivity (EC), alkalinity and hardness. The results revealed F− concentration ranges from 0.25–21.3 mg. An inverse relation between depth and fluoride concentration was observed. On the basis of cluster analysis three zones were identified. Highly toxic zone was a strip of 15 km wide and 3 km long, along Multan Road from Sunder to Phool Nagar bypass, with fluoride concentration (08–21.3 mg/L). The highly toxic zone inhabited a number of industrial units, disposing off their wastewater through soaking pits. These units contribute pollution to the shallow water, which further penetrates to the surroundings. Hence the shallow water (depth of 45–50 feet) was the most contaminated. The intensity of toxic effects decreases from highly to mild toxic zone. It was concluded that the problem was actually associated with the industrial wastewater. Therefore, to overcome the issue, measures of supplying fresh drinking water from the deep aquifer as well as treatment of industrial water is suggested. HIGHLIGHT Industry was actually responsible for fluoride toxicity in the region rather than natural sources.

Cape Town’s “Day Zero” Drought: Notes on a Future History of Urban Dwelling

Taking the events of Cape Town’s “Day Zero” drought as a case study, this article examines the politics and poetics of water in the Anthropocene and the implications of Anthropogenic climate change for urban life. It argues that rather than being understood as an inert resource, fresh drinking water is a complex object constructed at the intersection between natural systems; cultural imaginaries; and social, political, and economic interests. The extraordinary events of Day Zero raised the specter of Mad Max–style water wars. They also led to the development of new forms of solidarity, with water acting as a social leveler. The article argues that events in Cape Town open a window onto the future, to the extent that they tell us something about what happens when the added stresses of climate change are mapped onto already-contested social and political situations. They also underline the precarious nature of many of our urban arrangements. This sense of the precarious is likely to extend beyond the case of Cape Town and to be an abiding feature of urban life as we journey deeper into the Anthropocene/Capitalocene.

Fog-to-Water for Water Scarcity in Climate-Change Hazards Hotspots: Pilot Study in Southeast Asia.

Water is indispensable for human survival. Freshwater scarcity and unsustainable water are the main growing concerns in the world. It is estimated that about 800 million people worldwide do not have basic access to drinking water and about 2.2 billion people do not have access to safe water supply. Southeast Asia is most likely to experience water scarcity and water demand as a result of climate change. Climate change and the increasing water demand that eventually contribute to water scarcity are focused upon here. For Southeast Asia to adapt to the adverse consequences of global climate change and the growing concern of environmental water demand, fog water harvesting is considered as the most promising method to overcome water scarcity or drought. Fog water collection technique is a passive, low maintenance, and sustainable option that can supply fresh drinking water to communities where fog is a common phenomenon. Fog water harvesting system involves the use of mesh nets to collect water as fog passes through them. Only minimal cost is required for the operation and maintenance. In conclusion, fog water harvesting seems to be a promising method that can be implemented to overcome water scarcity and water demand in Southeast Asia.

Impact of Nitrate Vulnerable Zones and Catchment Sensitive Farming on Water Quality in UK: Case Study of Ingbirchworth and Scout Dyke Reservoirs

The rivers and water streams are considered as a source of fresh drinking water for the human being on earth. The main source of water entering to these reservoirs is surface run off, snow melting and underground water. The water at the river’s mouth is generally in the form of small streams which are considered clean but as they flow down the catchment, pollutants and nutrients start to enter in larger amounts due to anthropogenic activities and advanced land use by human beings. As per inspection of chief inspector “Drinking Water Inspectorate (DWI)” in 2016, out of more than 4600 water bodies and 3700 rivers in England, only one sixth could get “good” status and two third could get “moderate” status as per European union standards. This is though a good achievement in Europe but alarming also, as all rivers are required to have achieved specified “good” standards by 2021 (extended to 2027 for some categories). This phenomenon is pronouncing more complications in drinking water reservoirs or compensatory reservoirs from where water is taken out to utility companies and treated for domestic water supply incurring an enormous cost on its treatment before human consumption. The clean water standards can be achieved only if a strict control is implemented on entry of pollutants/ nutrients from surface run off using thorough catchment scale sensitive strategies. UK has been implementing strict measures under Environment Agency (EA), Department for Environment, Food and Rural Affairs (DEFRA) and other organizations like “Natural England”, “River Trust” and water utility/ supply companies to achieve desired standards of water quality in rivers by managing the whole catchment as per European union water framework directive (EU WFD) 2000.The catchment sensitive farming and nitrate vulnerable zones policies were started in 1992 and has been in full practice by implementing different stewardship schemes and fertilizers control measures in farmlands and arable lands. Ingbirchworth reservoir and Scout Dyke compensatory reservoir have been under catchment sensitive stewardship schemes to control quantities of nutrients especially nitrates and other pollutants since 2006 to maintain good quality water reservoirs for drinking and compensation to Don river. A partial success has been achieved in controlling the values of nitrates, phosphates, and suspended solids to enter from catchment farmlands by controlling the use of slurry/ fertilizers and implementation of good farming techniques. However, temporal and special variations show a variable result of presence of nitrates, phosphates and suspended solids at different streams in different times, more than specified limits of 11.3mg/L, 0.1mg/L and 25mg/L respectively. This requires more holistic efforts to control the bad practices in farming in adjacent farm/arable lands and improvements in stewardship schemes for catchment sensitive farming in Ingbirchworth areas.

Beneficial effects of intermittent fasting on lipid profile and histotexture of heart in swiss albino mice

Intermittent fasting (IF) is a form of time restricted eating which has gained popularity in recent years and proposed benefits include the improvement of lipid profile and the body weight loss, has gained considerable scientific and popular repercussion. The present study was conducted to investigate the effect of IF on lipid profile and histomorphological changes of heart in mice. A total of 18 Swiss Albino Mice (Mus musculus), 28-35 days old with an average body weight of 26.2 ± 1 gm were randomly divided into three groups. Group A was considered as control (n=6) and fed on standard mice pellet and fresh drinking water. Group B was considered as 14 hours fasting group (n=6), kept fasting for 14 hrs. and Group C was considered as 18 hours fasting group (n=6), kept fasting for 18 hrs. At the end of the experiment, blood and tissue were collected for biochemical and histomorphological examination. Data showed that Total cholesterol, Low Density Lipoprotein (LDL) level (p<0.05) and Triglyceride level (p<0.01) were significantly lower whereas High Density Lipoprotein (HDL) was highly significant (p<0.01) in 14 hours and 18 hours fasting group than control group. Histopathological studies of heart revealed that normal nuclei and no architectural changes were observed in myocardium in both control and fasting groups. It can be concluded that intermittent fasting may have promoting action on heart health as its limits the development of cardiovascular diseases by significantly increasing the HDL level that is known as good cholesterol for health.

Effects of Fasting on Body Weight, Serum Glucose and Creatinine and Histotexture of Liver and Kidney in Swiss Albino Mice

Fasting means remaining without foods and water from a specific period of time which is important for improving health and increasing longevity. The present study was conducted to investigate the effect of fasting on body weight, serum biochemistry and histomorphological changes of liver and kidney in mice. A total of 18 Swiss Albino Mice (Musmusculus), 28-35 days old with an average body weight of 26.2 ± 1 gm were randomly divided into three groups. Group A was considered as control (n=6) and fed on standard mice pellet and fresh drinking water. Group B was considered as 14 hours fasting group (n=6), kept fasting for 14 hrs and Group C was considered as 18 hours fasting group (n=6), kept fasting for 18 hrs. At the end of the experiment, blood and tissues were collected for biochemical and histomorphological examination. Data showed that no significant change was found in body weight, serum glucose and creatinine level in fasting groups Histopathological studies of liver and kidney revealed that fasting could initiate minor change in the normal structures of liver but no architectural change in kidney. Slight depletion of glycogen was found in hepatocytes of liver. From the present study it can be concluded that fasting may be beneficial as its decreases body weight gain and have not any significant alteration in the liver and kidney histotextures.&#x0D; Res. Agric., Livest. Fish.7(3): 421-430, December 2020

Violencia directa y conflictos distributivos sobre el agua. Evolución del debate analítico-conceptual y propuesta de nuevo enfoque

El artículo busca dos objetivos: a) exponer, en clave comparativa y treinta años más tarde del momento inicial y candente, los debates sobre la relación entre conflictos armados o violencia directa y situaciones de estrés/ carencia hídrica o enfrentamientos distributivos (recursos o cuencas compartidas, por ejemplo) por el agua. Al hacerlo, se añadirán a la sistematización los nuevos y más recientes enfoques; y b) a partir de los resultados del punto anterior, proponer nuevas herramientas para el análisis y la intervención en dichos conflictos, aprovechando, a modo de ejemplo y no de análisis detallado, diez casos heterogéneos activos en el presente de conflictos distributivos con el agua como incompatibilidad crucial. Los temas mencionados se popularizaron en los años noventa del siglo XX con afirmaciones impactantes que sostenían que “las próximas guerras no serían por petróleo o recursos minerales sino por el acceso al agua potable”. En ese sentido, la comparación se centra en examinar el debate entre 1985 y 1995, donde el tema dominante fue si la escasez/concurrencia por el agua podía o no ser factor causal directo de conflictos violentos o si era simplemente un factor multiplicador o acelerador vinculado a otras causas, con las aportaciones y enfoques actuales. Estas aportaciones, frente a la omnipresencia en los años noventa de enfoques y textos basados en estudios de seguridad y la entonces llamada “seguridad ecológica”, se centran actualmente en las herramientas que proporcionan los estudios sobre análisis, resolución y transformación de conflictos y en nuevas reflexiones epistemológicas respetuosas del sesgo cultural y de género y no occidentalocéntricas. El texto, además de introducción y conclusiones, tiene tres apartados. El primero establece un punto de partida fáctico, resumiendo los datos relativos al agua dulce y potable, para establecer, mediante una sucinta descripción de diez conflictos, internos e internacionales, de varios continentes, una tesis central: la conflictividad más caliente, incluyendo conductas violentas, no es tanto por la carencia de agua en sí, sino por la gestión y gobernanza del agua, en general y en casos de escases de la misma. En segundo lugar, se resume las claves analíticas y los resultados del debate sobre los conflictos hídricos, en particular sobre los vínculos entre uso y escasez de agua y violencia directa desde finales de los años ochenta a mediados de los años noventa del siglo pasado. La tercera sección presenta nuevas miradas, basadas no en los estudios de seguridad o la seguridad ecológica, como antes, sino en los trabajos, consolidados, de la investigación para la paz y los estudios sobre análisis y transformación de conflictos. Concretamente, se exponen las aportaciones, y se propone como aplicarlas a los conflictos hídricos, mediante tres asunciones y siete tesis. Finalmente, las conclusiones insisten en la necesidad de tratar estos conflictos como conflictos sociales, mostrando que su especificidad está vinculada a la gestión y gobernanza del recurso más que a la escasez en sí y, al hacerlo, ponen el acento, en las dificultades de gobernabilidad y gobernanza que hay que abordar.

Stepped solar still: A review on designs analysis

Everyone’s rights to get clean, safe, and fresh drinking water. As we know almost 71% of water covered in the Earth's surface. It may be in the form of oceans (covers almost 96.5% of all Earth's water), rivers, lakes, glaciers, icecaps, and also exists in the form of water vapor as well as soil moistures. The percentage of freshwater on earth is about 3% in which almost 2.5% fresh water is not available (locked in polar ice caps, atmosphere, glaciers, highly polluted, in soil, or lie too deep below the surface of the earth and not to be collected at a reasonable cost. Fresh water is available only 0.5% of the earth's atmosphere. Solar desalination from a solar still is a renewable method used to fulfill the provision of safe water supply in distant locations at a very affordable cost. However, due to its lower awareness solar still technology is not standardized and commercialized. The factors that influence solar still productivity are wind velocity, solar intensity, depth of water, an inlet water temperature, ambient temperature, and absorber plate area etc. ambient temperature, solar intensities and wind velocity are unable to control because these are metrological variables while the left standing variables could be changed to enhance solar stills productivity. Water depth in solar still inversely affects solar still productivity. Investigations suggest that reduction in brine depth productivity increases, because of higher temperatures in the basin. Minimum depth is maintained by stepped solar still, so stepped solar stills can improve the distillate Productivity. Throughout this review, we attempt to study the various types of stepped solar stills.

Influence of crushed maize and soybean cake on the growth of crossbred female calves

The present research work was conducted to develop a balanced ration for crossbred high yielding calves in farm condition. For this purpose, seventy days long feeding trial was conducted with nine crossbred female calves having nearly similar body weight and age. Nine crossbred calves were equally divided into three groups such as T1 (1 kg concentrate mixture of crushed maize, wheat bran, mustard oil cake, molasses, DCP and salt at a ratio of 25:45:22:5:1:2, respectively), T2 (1 kg concentrate mixture of crushed maize, wheat bran, soybean cake, molasses, DCP and salt at a ratio of 27:45:20:5:1:2, respectively) and T3 (Wheat bran, rice polish, mustard oil cake, DCP, Salt were supplied according to BAU routine farm feeding at a ratio of 65:18:14:1:2, respectively). All calves were supplied with ad libitum green grasses (German and Para) and fresh clean drinking water. From the research finding, it was observed that the average total dry matter intake, total body weight gain, body length gain and heart girth gain were in T1 (2.68a±0.000 kg, 2.51a±0.21 kg, 1.83a±0.12 cm, 1.29a±0.07 cm, respectively) and T2 (2.65a±0.001 kg, 2.55a±0.21 kg, 1.67a±0.12 cm, 1.25a±0.07 cm, respectively) groups significantly (p&lt;0.05) higher than that of the T3 (2.34b±0.002 kg, 0.96b±0.21 kg, 0.81b±0.12 cm, 0.64b±0.07 cm, respectively) group. The result showed that the body weight gain of T2 group was higher by supplementation of balanced ration. Therefore, the feed supplementation of crushed maize, wheat bran, soybean cake, molasses, DCP and salt at a ratio of 27:45:20:5:1:2, respectively should be supplied to crossbred calves for the future development of dairy herd replacement stock for profitable dairy business.&#x0D; Asian J. Med. Biol. Res. September 2020, 6(3): 499-506

Adoption of organic farming practices in the rural household of South-South, Nigeria—a case study

Comparative analysis of organic farming practices among farmers in South-South, Nigeria, was carried out. A review of previous studies on organic farming practices showed that little effort has been made by researchers to capture South-South agricultural zone. There is scarcely any empirical data on organic farming practices used by crop, livestock, and fish farmers in the study area. This has created a gap in knowledge which the outcome of this study intends to bring out. This study did not only determine whether there is difference in organic farming practices among farmers in the different states under study but assessed the farmers level of awareness and use of organic farming practices, and relationship between the level of use of organic farming practices and the farmers’ socio-economic characteristics. Multistage random selection technique was used to select rural household farmers engaged in fish, livestock, and crop production. A sample of four hundred and eighty farmers was used. Organic farming practices among crop farmers included the use of farmyard manure ( $$ \overline{x} $$ = 2.79), inter cropping ( $$ \overline{x} $$ = 2.58), mulching ( $$ \overline{x} $$ = 2.50), and spot bush burning ( $$ \overline{x} $$ = 2.50). The organic farming practices among livestock farmers were access to fresh drinking water ( $$ \overline{x} $$ = 2.77) and adequate feeding ( $$ \overline{x} $$ = 2.65). Fish farmers engaged in the use of three organic practices: eco-friendly design ( $$ \overline{x} $$ = 2.56), site being far from polluting substances ( $$ \overline{x} $$ = 2.57) and pond protection from predators ( $$ \overline{x} $$ = 2.70). There were significant differences in the farmers’ level of use of organic farming practices based on their states of origin (Akwa-Ibom, Bayelsa, and Delta). Education, age, and income were the socio-economic determinants of the level of use of organic farming practices. It was concluded that farmers’ in Akwa Ibom state engaged more in the use of organic farming practices, followed by Bayelsa state and the least is Delta state.

Experimental investigation on the performance enhancement of single basin double slope solar still using kanchey marbles as sensible heat storage materials

The problem of water scarcity is increasing day by day due to various causes such as polluting the environment, urbanization, climate change due to the heavy usage of fossil fuels, less awareness in storing the water when it is available, etc. However, in seashore areas, the availability of fresh drinking water is very low. This demand motivated to suggest a low cost and renewable energy based desalination system to convert the brackish water into potable water. Solar still is a simple device which can convert the available waste or brackish water into fresh potable drinking water utilizing solar energy. The designed solar still was fabricated and tested under the normal atmospheric condition. Present work is to investigate the effect of kanchey marbles as energy storage material in the overall efficiency of solar stills. The performance of the solar still with kanchey marbles was 16.32% higher than the conventional still.

Surface and groundwater quality assessment and identification of hydrochemical characteristics of a south-western coastal area of Bangladesh.

In coastal areas of Bangladesh, the problem of getting fresh drinking water is acute since the surface and groundwater of this area are affected by both seawater intrusion and anthropogenic activities. This study aims at assessing the hydrochemistry and quality of surface and groundwater of a south-western coastal area Rupsha Upazila of Bangladesh using geographical information system (GIS) technique. The hydrochemical facies revealed that the surface waters are mainly characterized by Na-Ca-HCO3-Cl and the groundwaters are characterized by Na-Cl-HCO3, indicating mixing composition of the natural water, while the Gibbs diagram indicates mixing processes of both the rock-water and evaporation-crystallization interactions of the surface and groundwater. The comparisons of the water quality parameters with World Health Organization (WHO) and Bangladesh (BD) standards show that surface water quality is better than groundwater in terms of total dissolved solids, chloride, iron, and arsenic concentrations. In surface water, arsenic concentration is within the WHO and BD standard but 40% of the groundwater samples exceeded the standard. Results also showed that 100% of the surface water samples exceeded the Escherichia coli and 62.85% of the groundwater samples exceeded the standard limit. Thus, the surface water of the study area can be a potential source to meet the future challenges for drinking water shortage problems as compared to aquifer water of the area.

Sustainable synthesis of zinc oxide nanoparticles for photocatalytic degradation of organic pollutant and generation of hydroxyl radical

Abstract Herein, a sustainable and reproducible method for the preparation of zinc oxide nanoparticles (ZnO) and their application in photocatalytic degradation of organic pollutant is reported. The ZnO nanoparticles were prepared by combusting a mixture of highly porous sawdust and zinc nitrate hexahydrate at 600 °C in a tube furnace. The porous morphology of the sawdust mediated the formation of ZnO nanoparticles by preventing their growth to the macroscopic size. Four different ZnO nanoparticles samples [ZnO-n, where n = 1–4] were prepared by varying the ratio of sawdust and zinc nitrate salt to obtain the best-performing ZnO nanoparticles. The average size of the ZnO nanoparticles was found to be ~ 23 nm, measured from TEM image. The ZnO-4 and ZnO-2 degraded ~ 95% methyl orange (MO) in deionized and simulated fresh drinking water matrices after 42 min of ultraviolet (UV-B) light irradiation. The ZnO-2 and ZnO-4 catalyzed degradation of MO in deionized and fresh drinking water matrices were found to be about 24 and 27 times faster compared to the ZnO-control. The ability of ZnO-n towards the generation of hydroxyl radicals (•OH) was studied by the terephthalic acid fluorescence tests. Additionally, the reproducibility of the synthesis methodology and the cyclic stability of the as prepared ZnO-n was thoroughly studied. Finally, it was found that the ZnO nanoparticles, prepared in this study, leached less amount of zinc in water compared to the commercial ZnO; which indicated its better safety and sustainability in regard to the photocatalytic water treatment.

Sulfonated Poly(ether sulfone) based sulfonated molybdenum sulfide composite membranes and their applications in salt removal and alkali recovery

The adequate and potable water to meet present and future demand is much lower than the fresh water available. To fulfil the surplus demand of fresh drinking water, the management and treatment of waste water to be taken forward. In this view, electrodialysis (ED) has attracted immense attention nowadays to satisfy current water demands for drinking and industrial purpose. Ion exchange membranes are the cores of electrodialysis. Herein, composite cation exchange membranes are prepared for salt removal and water treatment using sulfonated poly(ether sulfone) (SPES) and sulfonated molybdenum sulfide (S–MoS2). Effect of S–MoS2 in membranes, water-related properties, ion transport, thermal and mechanical properties of synthesized composite membranes are evaluated. Incorporation of S–MoS2 in SPES enhance the performance of the membranes, and 5 wt % S–MoS2 composite membrane (DES-5) shows the 67% higher water sorption and 25% higher IEC compared to pristine SPES membrane. Their suitability is accessed in terms of salt removal via electrodialysis and alkali recovery via diffusion dialysis. The 5 wt % S–MoS2/SPES composite membrane exhibits 0.98 kWh/kg power consumption during salt removal that is 22% lower than 1.26 kWh/kg obtained for pristine SPES. Current efficiency towards salt removal and separation factor for alkali recovery for DES-5 membrane are 69.47% and 60.32, respectively, which are much higher than virgin SPES membrane.

MiR-155 antagomir protect against DSS-induced colitis in mice through regulating Th17/Treg cell balance by Jarid2/Wnt/β-catenin

BackgroundTh subsets particularly T helper 17 and regulatory T cells play a critical role in immune balance in colonic mucosa of Inflammatory Bowel Disease. Recent studies have indicated miR-155 is overexpressed in the colonic mucosa in IBD patients. Thus, whether and how miR-155 influences Th17/Treg cell balance in IBD patients is worthy of researching. MethodsWe divided mice into four groups: the mice oral administration of 3.0 % DSS in fresh drinking water for 7 days except normal group. In this period, starting from the fifth day, the miR-155 and NC antagomir group were carried out by intraperitoneal injection of miR-155 antagomirs and corresponding negative controls. In vitro, we isolated naïve CD4+T cells and divided into two groups: the cells were transfected with mmu-miR-155-5p inhibitor or corresponding negative controls and then induced differentiation. ResultsWe found miR-155 antagomir can reach colon tissues in DSS-induced colitis and indeed ameliorated DSS-induced experimental colitis. Subsequently, we proved the levels of Th17 cells in spleens and Mesenteric lymph nodes and its associated IL-6, IL-17A and RORγt in colonic tissues were dramatically decreased and TGF-β1 raised in DSS + miR-155 antagomir group. However, miR-155 antagomir significantly increased the expression of Tregs. In vitro, we found miR-155 inhibitor could improve the Tregs but decrease Th17 cells. Finally, we dig out that Jarid2 was apparently improved by miR-155 antagomir, Wnt/β-catenin and its associated T cell factor-4 (TCF-4) and Cyclin D1 expression were positively correlated with Jarid2. ConclusionSilencing of miR-155 attenuates DSS-induced colitis by regulating Th17/Treg cell balance and Jarid2/Wnt/β-catenin participated in the process.

EFFECT OF SODIUM CHLORIDE CONCENTRATION IN SAND BED AND WELL ON THE INDICATION OF NEUTRON LOGGING INSTRUMENTS

The requirements to the accuracy and reliability of the results of borehole geophysical measurements of the porosity coefficient in oil and gas fields are constantly increasing. Studies of the influence of chlorine on the readings of neutron logging equipment with different types of probes were carried out by mathematical modeling methods. Experimental evaluation of the simultaneous effect of sodium chloride concentration in the reservoir and in the well on the readings of neutron devices has not been carried out. A design description of the experimental bulk model of a porous watersaturated sand formation (a standard sample composition and properties of sand rock) crossed by a well created to study the effect of sodium chloride concentration in the formation and in the well on the readings of neutron logging equipment with various probes, as well as the results of metrological studies of the created model are given. A feature of the model design is the well simulator, made in the form of a cylindrical fiberglass cup and installed coaxially in a cylindrical stainless steel housing. The carriers of the model properties carriers are quartz gravel and an aqueous solution of sodium chloride (NaCl) in its pore space. Reproducible values of porosity model taking into account heterogeneity of crushed stone backfill (0.353 ± 0.002) with probability 1 defined by volumetric and gravimetric methods under normal conditions, the sandy layer, pore space which is filled with fresh drinking water. The results of experimental studies of the effect of aqueous NaCl solution in a sand formation and in a well with concentrations of 50, 100, 150 and 200 g/l on the indication of neutron logging equipment PRKL with probe NGK, RK5-76 with probe NNK-T and SRK-1 with probe NNKNT using individual calibration functions (CF). CF were built on the porosity standards of sandy water-saturated rocks with zero NaCl concentration in the Center of metrological research «Ural-Geo». Correction functions (CF) are given as a dependence of the correction to the readings of the equipment RK5-76 and PRKL on the concentration of NaCl in the formation at a fixed concentration in the well or on the concentration of NaCl in the well at a fixed concentration in the formation. The obtained results can be used in the development of techniques for performing downhole geophysical measurements of the porosity coefficient of rock formations in typical geological and technical conditions.

Performance Evaluation of a Double Slope Concrete Cascade Solar Stills

The availability of drinking water is one of the major challenges faced by our modern society. There are certain locations where fresh drinking water is scarce, but brackish or saline water are available. The available water resources have been used to provide a clean, safe and reliable drinking water with metal basin solar stills using solar energy. The issue of rusting associated with the metal basin solar still constitutes a major problem. A concrete cascade double slope solar still was constructed and tested alongside a conventional metal basin solar still of the same dimensions. The performance tests compared the glass cover and basin water temperatures, as well as the yields of the two stills recorded at 30minutes interval, for seven days. The highest average daily glass temperatures for metal and concrete basin stills of 54.1 °C and 40.5 °C were recorded respectively for the metal basin and concrete cascade solar stills, at an average highest global solar radiation of 867.3W/m2 and an ambient temperature of 35.1 °C. The highest average daily water temperatures of 58.3 °C and 51.1 °C occurred respectively for the metal basin and concrete cascade stills at the same time under the same atmospheric conditions. The average daily cumulative yields of the metal basin and concrete cascade solar stills were found to be 707.1 mL 577.4 mL respectively. The results show that the conventional metal basin solar still recorded a higher yield, but the concrete cascade solar still has overcome the rusting problem. There is, therefore, a compromise of 18.3% higher yield or a longer span working solar still without rusting.

Modeling and Experimental Investigation of Solar Stills for Enhancing Water Desalination Process

Despite the importance of the desalination process in removal of water salinity to produce fresh drinking water, it is an energy-consuming process. Therefore, the use of solar energy as an alternative and free energy source has an important role in enhancing the efficiency of the desalination process. This paper presents an experimental investigation using solar chimney to enhance the desalination process, where a modification to the conventional solar stills has been made. A mathematical model describing air flow inside the solar chimney has been constructed using Computational Fluid Dynamics (CFD). The commercial CFD package fluent release 6.3 has been used in this paper to express the air flow and temperature distribution inside solar chimney. Furthermore, the process parameters such as seasonal temperature, salt concentration, water depth and type of solar desalination unit have been examined to find the best operating conditions. The desalination process has been recommended to be carried out under permissible operating conditions in sunny days, with water depths ranging from (1–2 cm) and low salt concentration ranging from (3.5–8%). The modeled data has been verified with experimental data and the verification results have been estimated at 14%. Simulation results showed that water desalination has been improved by 30%.

Development of photocatalytic paint based on TiO2 and photopolymer resin for the degradation of organic pollutants in water

While the use of TiO2 nanoparticles in the form of slurry/suspension requires energy-intensive separation processes, its immobilization in solid support may open new opportunities in the area of sustainable water treatment technologies. In this study, a novel method for the development of photocatalytic paint based on TiO2 nanoparticles and acrylate-based photopolymer resin is reported. The paint (TiO2@polymer) was applied on substrates such as plastic petri dish and glass jar, which was polymerized/solidified by ultraviolet light irradiation. The painted petri dish and glass jar were used for the photocatalytic degradation of model organic pollutants viz. methyl orange (MO), methylene blue (MB), and indole in deionized water, simulated fresh drinking water, and tap water matrices. The photocatalytic degradation studies were performed under sunlight and UV-B light were used for. The sunlight-assisted photocatalytic degradation of MO and MB was found to be faster and more efficient than the UV-B light-assisted ones. Under UV-B light irradiation, it took 120 min to degrade about 80% of 6 ppm MB solution, whereas under sunlight irradiation it took 60 min to degrade about 90% of the same MB solution. The photocatalytic paint generated hydroxyl radical (·OH) under the UV-B and sunlight irradiation, which was studied by the terephthalic acid fluorescence tests. Further, the potential release of TiO2 during the exposure to UV irradiation was studied by single particle ICP-MS analysis.

Influence of water mass on the performance of spherical basin solar still integrated with parabolic reflector

Continuous availability of fresh drinking water to meet the growing social, economic and environmental need of society is one of the major concern for present situation. Solar desalination is sustainable device to get the potable water from brackish water. However, the lower productivity of solar desalination is the major obstacle for worldwide applicability. In the present paper, an ingenious amendment in form of spherical basin solar still has been integrated with parabolic reflector. The spherical basin solar still has been developed and performance has been investigated for various water mass such as 1 L, 2 L, 3 L, 4 L and 5 L in basin. The daily yield of 3.5409 L/m2, 4.7860 L/m2, 6.7174 L/m2, 7.4744 L/m2 and 8.2596 L/m2 was obtained for 1 L, 2 L, 3 L, 4 L and 5 L water mass in basin respectively. The daily average efficiency of spherical basin solar still was obtained 19.56%, 23.92%, 30.83%, 34.49%, 39.06% for the 1 L, 2 L, 3 L, 4 L, 5 L water mass in basin respectively. From experimental results, it has found that the distilled output increases with increase in mass of water in basin.