Search results for: ²¹⁰PB/²¹⁰BI in water
5326 An Analysis of LoRa Networks for Rainforest Monitoring
Authors: Rafael Castilho Carvalho, Edjair de Souza Mota
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As the largest contributor to the biogeochemical functioning of the Earth system, the Amazon Rainforest has the greatest biodiversity on the planet, harboring about 15% of all the world's flora. Recognition and preservation are the focus of research that seeks to mitigate drastic changes, especially anthropic ones, which irreversibly affect this biome. Functional and low-cost monitoring alternatives to reduce these impacts are a priority, such as those using technologies such as Low Power Wide Area Networks (LPWAN). Promising, reliable, secure and with low energy consumption, LPWAN can connect thousands of IoT devices, and in particular, LoRa is considered one of the most successful solutions to facilitate forest monitoring applications. Despite this, the forest environment, in particular the Amazon Rainforest, is a challenge for these technologies, requiring work to identify and validate the use of technology in a real environment. To investigate the feasibility of deploying LPWAN in remote water quality monitoring of rivers in the Amazon Region, a LoRa-based test bed consisting of a Lora transmitter and a LoRa receiver was set up, both parts were implemented with Arduino and the LoRa chip SX1276. The experiment was carried out at the Federal University of Amazonas, which contains one of the largest urban forests in Brazil. There are several springs inside the forest, and the main goal is to collect water quality parameters and transmit the data through the forest in real time to the gateway at the uni. In all, there are nine water quality parameters of interest. Even with a high collection frequency, the amount of information that must be sent to the gateway is small. However, for this application, the battery of the transmitter device is a concern since, in the real application, the device must run without maintenance for long periods of time. With these constraints in mind, parameters such as Spreading Factor (SF) and Coding Rate (CR), different antenna heights, and distances were tuned to better the connectivity quality, measured with RSSI and loss rate. A handheld spectrum analyzer RF Explorer was used to get the RSSI values. Distances exceeding 200 m have soon proven difficult to establish communication due to the dense foliage and high humidity. The optimal combinations of SF-CR values were 8-5 and 9-5, showing the lowest packet loss rates, 5% and 17%, respectively, with a signal strength of approximately -120 dBm, these being the best settings for this study so far. The rains and climate changes imposed limitations on the equipment, and more tests are already being conducted. Subsequently, the range of the LoRa configuration must be extended using a mesh topology, especially because at least three different collection points in the same water body are required.Keywords: IoT, LPWAN, LoRa, coverage, loss rate, forest
Procedia PDF Downloads 755325 Identification of Suitable Rainwater Harvesting Sites Using Geospatial Techniques with AHP in Chacha Watershed, Jemma Sub-Basin Upper Blue Nile, Ethiopia
Authors: Abrha Ybeyn Gebremedhn, Yitea Seneshaw Getahun, Alebachew Shumye Moges, Fikrey Tesfay
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Rainfed agriculture in Ethiopia has failed to produce enough food, to achieve the increasing demand for food. Pinpointing the appropriate site for rainwater harvesting (RWH) have a substantial contribution to increasing the available water and enhancing agricultural productivity. The current study related to the identification of the potential RWH sites was conducted at the Chacha watershed central highlands of Ethiopia which is endowed with rugged topography. The Geographic Information System with Analytical Hierarchy Process was used to generate the different maps for identifying appropriate sites for RWH. In this study, 11 factors that determine the RWH locations including slope, soil texture, runoff depth, land cover type, annual average rainfall, drainage density, lineament intensity, hydrologic soil group, antecedent moisture content, and distance to the roads were considered. The overall analyzed result shows that 10.50%, 71.10%, 17.90%, and 0.50% of the areas were found under highly, moderately, marginally suitable, and unsuitable areas for RWH, respectively. The RWH site selection was found highly dependent on a slope, soil texture, and runoff depth; moderately dependent on drainage density, annual average rainfall, and land use land cover; but less dependent on the other factors. The highly suitable areas for rainwater harvesting expansion are lands having a flat topography with a soil textural class of high-water holding capacity that can produce high runoff depth. The application of this study could be a baseline for planners and decision-makers and support any strategy adoption for appropriate RWH site selection.Keywords: runoff depth, antecedent moisture condition, AHP, weighted overlay, water resource
Procedia PDF Downloads 415324 Comparative Study on the Thickening/Viscosity of Ogbono Seed Powder from Irvingia gabonenesis and Irvingia wombolu Species
Authors: Orlando Ketebu
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Ogbono seed is the seed obtained from African bush mango (Irvingia gabonenesis) and bitter bush mango (Irvingia wombolu). Irvingia gabonenesis is known for its sweet edible pulp while Irvingia wombolu has a bitter pulp. Their seed powder is used in cooking soup known as ogbono soup in Nigeria and in West Africa. The powder thickens when cooked and researches have shown that it has medicinal uses such as lowering cholesterol; aiding weight loss and helps in improving diabetes control. The nutritional composition of the seeds indicated that Irvingia gabonenesis contains 8.60% protein, 13.8% carbohydrate, 2.0% moisture, 1.5% crude fiber, 16.4% ash, and Irvingia wombolu contains 7.38% protein, 25.75% carbohydrate, 11.7% moisture, 0.84% crude fiber, 2.50% ash. Solvent extraction of these seeds has shown that the seed of the two species are oil seeds with approximately 70 % and 52 % for Irvingia gabonenesis and Irvingia wombolu respectively. One major setback using ogbono seed powder in cooking soup is identifying the specie of ogbono seed powder that thickens most within the same cooking condition and how temperature affects the thickness of ogbono seed powder which determines its viscosity and in turn affects the quality of the soup and its nutrients. This research work monitored how the viscosity of ogbono species after being sun dried for one week changes with temperature. The result showed that heating 20 grams of powdered Irvingia gabonenesis and Irvingia wombolu at 30 OC, 45 OC, 55 OC, 65 OC, 75 OC, 85 OC and 95OC respectively in 200 ml beaker mixed with 100 ml of water, the viscosity of both species decreases with increase temperature with Irvingia wombolu having higher average viscosity in Pascal seconds (Pa.s) of 1.059, 1.042, 0.961, 0.778, 0.684, 0.675, and 0.495 at 30 OC, 45 OC, 55 OC, 65 OC, 75 OC, 85 OC and 95 OC respectively compared to Irvingia gabonenesis with result 0.982, 0.920, 0.720, 0.646, 0.597 and 0.446 at 30 OC, 45 OC, 55 OC, 65 OC, 75 OC, 85 OC and 95 OC respectively. Also from the experiment carried out it was found out that the viscosity of both species decreases with ageing of the seeds and the quantity of ogbono seed powder used and amount of water added also affected the viscosity of both species. In conclusion, it was observed that under the same cooking conditions (temperature range, quantity of water added, time and quantity of ogbono seed powder used), Irvingia wombolu had higher viscosity which is a measure of its thickness and quality of nutrients compared to Irvingia gabonenesis and the viscosity of both species decreases with increasing temperature.Keywords: ogbono seed powder, temperature, viscosity , soup
Procedia PDF Downloads 1835323 An Energy and Economic Comparison of Solar Thermal Collectors for Domestic Hot Water Applications
Authors: F. Ghani, T. S. O’Donovan
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Today, the global solar thermal market is dominated by two collector types; the flat plate and evacuated tube collector. With regards to the number of installations worldwide, the evacuated tube collector is the dominant variant primarily due to the Chinese market but the flat plate collector dominates both the Australian and European markets. The market share of the evacuated tube collector is, however, growing in Australia due to a common belief that this collector type is ‘more efficient’ and, therefore, the better choice for hot water applications. In this study, we investigate this issue further to assess the validity of this statement. This was achieved by methodically comparing the performance and economics of several solar thermal systems comprising of; a low-performance flat plate collector, a high-performance flat collector, and an evacuated tube collector coupled with a storage tank and pump. All systems were simulated using the commercial software package Polysun for four climate zones in Australia to take into account different weather profiles in the study and subjected to a thermal load equivalent to a household comprising of four people. Our study revealed that the energy savings and payback periods varied significantly for systems operating under specific environmental conditions. Solar fractions ranged between 58 and 100 per cent, while payback periods range between 3.8 and 10.1 years. Although the evacuated tube collector was found to operate with a marginally higher thermal efficiency over the selective surface flat plate collector due to reduced ambient heat loss, the high-performance flat plate collector outperformed the evacuated tube collector on thermal yield. This result was obtained as the flat plate collector possesses a significantly higher absorber to gross collector area ratio over the evacuated tube collector. Furthermore, it was found for Australian regions operating with a high average solar radiation intensity and ambient temperature, the lower performance collector is the preferred choice due to favorable economics and reduced stagnation temperature. Our study has provided additional insight into the thermal performance and economics of the two prevalent solar thermal collectors currently available. A computational investigation has been carried out specifically for the Australian climate due to its geographic size and significant variation in weather. For domestic hot water applications were fluid temperatures between 50 and 60 degrees Celsius are sought, the flat plate collector is both technically and economically favorable over the evacuated tube collector. This research will be useful to system design engineers, solar thermal manufacturers, and those involved in policy to encourage the implementation of solar thermal systems into the hot water market.Keywords: solar thermal, energy analysis, flat plate, evacuated tube, collector performance
Procedia PDF Downloads 2065322 Photocatalytic Degradation of Lead from Aqueous Solution Using TiO2 as Adsorbent
Authors: Navven Desai, Veena Soraganvi
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Heavy metals such as lead, cadmium and mercury do not have biological significance hence they are known to be extremely toxic heavy metals. Water contains various heavy metals like Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Arsenic (As), Lead (Pb), and Zinc (Zn) etc., when it gets polluted with industrial waste water. These heavy metals cause various health effects even at low concentration when consumed by humans. Most of the heavy metals are poisonous to living organisms. Heavy metals are non-degradable and are preserved in the environment through bioaccumulation. Therefore removal of heavy metals from water is necessary. In recent years, a great deal of attentions has been focused on to the application of nanosized metal oxides to treat heavy metals, especially titanium oxides, ferric oxides, manganese oxides, aluminium oxides and magnesium oxides as adsorbent and photocatalyst. TiO2 based photocatalysts have attracted continuously increasing attention because of the excellent properties such as high light -conversion efficiency, chemical stability, nontoxic nature, low cost. The catalyst displays high photocatalytic activity because of its large surface area. In this study, the photocatalytic degradation of Lead (Pb) from aqueous solution was investigated in natural sunlight by using TiO2 as Nanomaterial. This study was performed at laboratory scale. All the experiments were carried out in the batch process. The concentration of lead was constant (25mg/lit) in the experiment and effect of titanium dioxide dose and pH were varied to study the removal efficiency of the lead by adsorption. Further study was performed on the dependence of photocatalytic reaction on the reaction temperature. The aqueous solution was prepared by Lead metal powder. TiO2 photo catalyst nanopowder used was Sisco-74629 grade. The heavy metal is analyzed with VARIAN AA 240 atomic adsorption spectrophotometer. The study shows, with increasing TiO2 dose and pH the lead removal increases. According to study, it can be concluded that the utilization of titanium dioxide accounted for higher efficiency in the removal of lead from aqueous solution.Keywords: adsorption, heavy metals, nanomaterial, photocatalysis
Procedia PDF Downloads 2905321 Quantification of Leachate Potential of the Quezon City Controlled Dumping Facility Using Help Model
Authors: Paul Kenneth D. Luzon, Maria Antonia N. Tanchuling
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The Quezon City Controlled Dumping facility also known as Payatas produces leachate which can contaminate soil and water environment in the area. The goal of this study is to quantify the leachate produced by the QCCDF using the Hydrologic Evaluation of Landfill Performance (HELP) model. Results could be used as input for groundwater contaminant transport studies. The HELP model is based on a simple water budget and is an essential “model requirement” used by the US Environmental Protection Agency (EPA). Annual waste profile of the QCCDF was calculated. Based on topographical maps and estimation of settlement due to overburden pressure and degradation, a total of 10M m^3 of waste is contained in the landfill. The input necessary for the HELP model are weather data, soil properties, and landfill design. Results showed that from 1988 to 2011, an average of 50% of the total precipitation percolates through the bottom layer. Validation of the results is still needed due to the assumptions made in the study. The decrease in porosity of the top soil cover showed the best mitigation for minimizing percolation rate. This study concludes that there is a need for better leachate management system in the QCCDF.Keywords: help model, landfill, payatas trash slide, quezon city controlled dumping facility
Procedia PDF Downloads 2835320 Challenge of Baseline Hydrology Estimation at Large-Scale Watersheds
Authors: Can Liu, Graham Markowitz, John Balay, Ben Pratt
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Baseline or natural hydrology is commonly employed for hydrologic modeling and quantification of hydrologic alteration due to manmade activities. It can inform planning and policy related efforts for various state and federal water resource agencies to restore natural streamflow flow regimes. A common challenge faced by hydrologists is how to replicate unaltered streamflow conditions, particularly in large watershed settings prone to development and regulation. Three different methods were employed to estimate baseline streamflow conditions for 6 major subbasins the Susquehanna River Basin; those being: 1) incorporation of consumptive water use and reservoir operations back into regulated gaged records; 2) using a map correlation method and flow duration (exceedance probability) regression equations; 3) extending the pre-regulation streamflow records based on the relationship between concurrent streamflows at unregulated and regulated gage locations. Parallel analyses were perform among the three methods and limitations associated with each are presented. Results from these analyses indicate that generating baseline streamflow records at large-scale watersheds remain challenging, even with long-term continuous stream gage records available.Keywords: baseline hydrology, streamflow gage, subbasin, regression
Procedia PDF Downloads 3165319 Mining Coupled to Agriculture: Systems Thinking in Scalable Food Production
Authors: Jason West
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Low profitability in agriculture production along with increasing scrutiny over environmental effects is limiting food production at scale. In contrast, the mining sector offers access to resources including energy, water, transport and chemicals for food production at low marginal cost. Scalable agricultural production can benefit from the nexus of resources (water, energy, transport) offered by mining activity in remote locations. A decision support bioeconomic model for controlled environment vertical farms was used. Four submodels were used: crop structure, nutrient requirements, resource-crop integration, and economic. They escalate to a macro mathematical model. A demonstrable dynamic systems framework is needed to prove productive outcomes are feasible. We demonstrate a generalized bioeconomic macro model for controlled environment production systems in minesites using systems dynamics modeling methodology. Despite the complexity of bioeconomic modelling of resource-agricultural dynamic processes and interactions, the economic potential greater than general economic models would assume. Scalability of production as an input becomes a key success feature.Keywords: crop production systems, mathematical model, mining, agriculture, dynamic systems
Procedia PDF Downloads 725318 Downward Vertical Evacuation for Disabilities People from Tsunami Using Escape Bunker Technology
Authors: Febrian Tegar Wicaksana, Niqmatul Kurniati, Surya Nandika
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Indonesia is one of the countries that have great number of disaster occurrence and threat because it is located in not only between three tectonic plates such as Eurasia plates, Indo-Australia plates and Pacific plates, but also in the Ring of Fire path, like earthquake, Tsunami, volcanic eruption and many more. Recently, research shows that there are potential areas that will be devastated by Tsunami in southern coast of Java. Tsunami is a series of waves in a body of water caused by the displacement of a large volume of water, generally in an ocean. When the waves enter shallow water, they may rise to several feet or, in rare cases, tens of feet, striking the coast with devastating force. The parameter for reference such as magnitude, the depth of epicentre, distance between epicentres with land, the depth of every points, when reached the shore and the growth of waves. Interaction between parameters will bring the big variance of Tsunami wave. Based on that, we can formulate preparation that needed for disaster mitigation strategies. The mitigation strategies will take the important role in an effort to reduce the number of victims and damage in the area. It will reduce the number of victim and casualties. Reducing is directed to the most difficult mobilization casualties in the tsunami disaster area like old people, sick people and disabilities people. Until now, the method that used for rescuing people from Tsunami is basic horizontal evacuation. This evacuation system is not optimal because it needs so long time and it cannot be used by people with disabilities. The writers propose to create a vertical evacuation model with an escape bunker system. This bunker system is chosen because the downward vertical evacuation is considered more efficient and faster. Especially in coastal areas without any highlands surround it. The downward evacuation system is better than upward evacuation because it can avoid the risk of erosion at the ground around the structure which can affect the building. The structure of the bunker and the evacuation process while, and even after, disaster are the main priority to be considered. The power of bunker has quake’s resistance, the durability from water stream, variety of interaction to the ground, and waterproof design. When the situation is back to normal, victim and casualties can go into the safer place. The bunker will be located near the hospital and public places, and will have wide entrance supported by large slide in it so it will ease the disabilities people. The technology of the escape bunker system is expected to reduce the number of victims who have low mobility in the Tsunami.Keywords: escape bunker, tsunami, vertical evacuation, mitigation, disaster management
Procedia PDF Downloads 4875317 Dynamic Model for Forecasting Rainfall Induced Landslides
Authors: R. Premasiri, W. A. H. A. Abeygunasekara, S. M. Hewavidana, T. Jananthan, R. M. S. Madawala, K. Vaheeshan
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Forecasting the potential for disastrous events such as landslides has become one of the major necessities in the current world. Most of all, the landslides occurred in Sri Lanka are found to be triggered mostly by intense rainfall events. The study area is the landslide near Gerandiella waterfall which is located by the 41st kilometer post on Nuwara Eliya-Gampala main road in Kotmale Division in Sri Lanka. The landslide endangers the entire Kotmale town beneath the slope. Geographic Information System (GIS) platform is very much useful when it comes to the need of emulating the real-world processes. The models are used in a wide array of applications ranging from simple evaluations to the levels of forecast future events. This project investigates the possibility of developing a dynamic model to map the spatial distribution of the slope stability. The model incorporates several theoretical models including the infinite slope model, Green Ampt infiltration model and Perched ground water flow model. A series of rainfall values can be fed to the model as the main input to simulate the dynamics of slope stability. Hydrological model developed using GIS is used to quantify the perched water table height, which is one of the most critical parameters affecting the slope stability. Infinite slope stability model is used to quantify the degree of slope stability in terms of factor of safety. DEM was built with the use of digitized contour data. Stratigraphy was modeled in Surfer using borehole data and resistivity images. Data available from rainfall gauges and piezometers were used in calibrating the model. During the calibration, the parameters were adjusted until a good fit between the simulated ground water levels and the piezometer readings was obtained. This model equipped with the predicted rainfall values can be used to forecast of the slope dynamics of the area of interest. Therefore it can be investigated the slope stability of rainfall induced landslides by adjusting temporal dimensions.Keywords: factor of safety, geographic information system, hydrological model, slope stability
Procedia PDF Downloads 4125316 Floating Building Potential for Adaptation to Rising Sea Levels: Development of a Performance Based Building Design Framework
Authors: Livia Calcagni
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Most of the largest cities in the world are located in areas that are vulnerable to coastal erosion and flooding, both linked to climate change and rising sea levels (RSL). Nevertheless, more and more people are moving to these vulnerable areas as cities keep growing. Architects, engineers and policy makers are called to rethink the way we live and to provide timely and adequate responses not only by investigating measures to improve the urban fabric, but also by developing strategies capable of planning change, exploring unusual and resilient frontiers of living, such as floating architecture. Since the beginning of the 21st century we have seen a dynamic growth of water-based architecture. At the same time, the shortage of land available for urban development also led to reclaim the seabed or to build floating structures. In light of these considerations, time is ripe to consider floating architecture not only as a full-fledged building typology but especially as a full-fledged adaptation solution for RSL. Currently, there is no global international legal framework for urban development on water and there is no structured performance based building design (PBBD) approach for floating architecture in most countries, let alone national regulatory systems. Thus, the research intends to identify the technological, morphological, functional, economic, managerial requirements that must be considered in a the development of the PBBD framework conceived as a meta-design tool. As it is expected that floating urban development is mostly likely to take place as extension of coastal areas, the needs and design criteria are definitely more similar to those of the urban environment than of the offshore industry. Therefor, the identification and categorization of parameters takes the urban-architectural guidelines and regulations as the starting point, taking the missing aspects, such as hydrodynamics, from the offshore and shipping regulatory frameworks. This study is carried out through an evidence-based assessment of performance guidelines and regulatory systems that are effective in different countries around the world addressing on-land and on-water architecture as well as offshore and shipping industries. It involves evidence-based research and logical argumentation methods. Overall, this paper highlights how inhabiting water is not only a viable response to the problem of RSL, thus a resilient frontier for urban development, but also a response to energy insecurity, clean water and food shortages, environmental concerns and urbanization, in line with Blue Economy principles and the Agenda 2030. Moreover, the discipline of architecture is presented as a fertile field for investigating solutions to cope with climate change and its effects on life safety and quality. Future research involves the development of a decision support system as an information tool to guide the user through the decision-making process, emphasizing the logical interaction between the different potential choices, based on the PBBD.Keywords: adaptation measures, floating architecture, performance based building design, resilient architecture, rising sea levels
Procedia PDF Downloads 815315 Estimation of Aquifer Parameters Using Vertical Electrical Sounding in Ochudo City, Abakaliki Urban Nigeria
Authors: Moses. O. Eyankware, Benard I. Odoh, Omoleomo O. Omo-Irabor, Alex O. I. Selemo
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Knowledge of hydraulic conductivity and transmissivity is essential for the determination of natural water flow through an aquifer. These parameters are commonly estimated from the analysis of electrical conductivity, soil properties and fluid flow data. In order to achieve a faster and cost effective analysis of aquifer parameters in Ochudo City in Abakaliki, this study relied on non-invasive geophysical methods. As part of this approach, Vertical Electrical Sounding (VES) was conducted at 20 sites in the study area for the identification of the vertical variation in subsurface lithology and for the characterization of the groundwater system. The area variously consists of between five to seven geoelectric layers of different thicknesses. Depth to aquifer ranges from 9.94 m-134.0 m while the thickness of the identified aquifer varies between 8.43 m and 44.31 m. Based on the electrical conductivity values of water samples collected from two boreholes and two hand-dug wells within the study area, the hydraulic conductivity was determined to range from 0.10 to 0.433 m/day. The estimated thickness of the aquifer and calculated hydraulic conductivity were used to derive the aquifer transmissivity. The results indicate that this parameter ranges from 1.58-7.56 m²/day with a formation factor of between 0.31-3.6.Keywords: Asu river group, transmissivity, hydraulic conductivity, abakaliki, vertical electrical sounding (VES)
Procedia PDF Downloads 3855314 Improving the Strength Characteristics of Soil Using Cotton Fibers
Authors: Bindhu Lal, Karnika Kochal
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Clayey soil contains clay minerals with traces of metal oxides and organic matter, which exhibits properties like low drainage, high plasticity, and shrinkage. To overcome these issues, various soil reinforcement techniques are used to elevate the stiffness, water tightness, and bearing capacity of the soil. Such techniques include cementation, bituminization, freezing, fiber inclusion, geo-synthetics, nailing, etc. Reinforcement of soil with fibers has been a cost-effective solution to soil improvement problems. An experimental study was undertaken involving the inclusion of cotton waste fibers in clayey soil as reinforcement with different fiber contents (1%, 1.5%, 2%, and 2.5% by weight) and analyzing its effects on the unconfined compressive strength of the soil. Two categories of soil were taken, comprising of natural clay and clay mixed with 5% sodium bentonite by weight. The soil specimens were subjected to proctor compaction and unconfined compression tests. The validated outcome shows that fiber inclusion has a strikingly positive impact on the compressive strength and axial strain at failure of the soil. Based on the commendatory results procured, compressive strength was found to be directly proportional to the fiber content, with the effect being more pronounced at lower water content.Keywords: bentonite clay, clay, cotton fibers, unconfined compressive strength
Procedia PDF Downloads 1715313 The Impact on Habitat of Reef Traps Used in the Freshwater Shrimp (Palaemonetes antennarius, H. Milne Erwards, 1837) Catch
Authors: Cenkmen R. Begburs
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In Antalya region, freshwater shrimps are usually collected with scoops and tin traps. However, it can be catched by reef traps in some water sources. Freshwater shrimps are constantly catching for commercial reasons because of a favorite bait for angling. There are more or less damage catching fishing vehicles to the habitat. This study was carried out in the Kırkgöz spring, Antalya and examined the effect of reef traps on the Kırkgöz spring habitat. Reef traps used 18.5x23.5x25 cm perforated bricks are arranged next to each other, blocks of random dimensions are prepared in 5x10, 18x24, 7x8 meter dimensions. These blocks are constructed with two layers of bricks that are covered with various materials such as carpets and blankets. Then, freshwater shrimps enter the holes of bricks. The bricks are closed off from both sides and discharged into a container when it is desired to be caught. The reef traps built on the plants which staying on the plant for a long time have been damaging the vegetation under the reef traps. Fishermen are setting new traps on the plants to increase the fishing efficiency since the freshwater shrimps are among the water plants. As a result, this application disrupts the aquatic organisms in their habitats. It is important to use fishing gears which will cause less damage and conserve stocks for sustainable fishing.Keywords: reef trap, Antalya, environment, damage
Procedia PDF Downloads 1995312 Role of Process Parameters on Pocket Milling with Abrasive Water Jet Machining Technique
Authors: T. V. K. Gupta, J. Ramkumar, Puneet Tandon, N. S. Vyas
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Abrasive Water Jet Machining (AWJM) is an unconventional machining process well known for machining hard to cut materials. The primary research focus on the process was for through cutting and a very limited literature is available on pocket milling using AWJM. The present work is an attempt to use this process for milling applications considering a set of various process parameters. Four different input parameters, which were considered by researchers for part separation, are selected for the above application i.e. abrasive size, flow rate, standoff distance, and traverse speed. Pockets of definite size are machined to investigate surface roughness, material removal rate, and pocket depth. Based on the data available through experiments on SS304 material, it is observed that higher traverse speeds gives a better finish because of reduction in the particle energy density and lower depth is also observed. Increase in the standoff distance and abrasive flow rate reduces the rate of material removal as the jet loses its focus and occurrence of collisions within the particles. ANOVA for individual output parameter has been studied to know the significant process parameters.Keywords: abrasive flow rate, surface finish, abrasive size, standoff distance, traverse speed
Procedia PDF Downloads 2935311 The Effect of Extrusion Processing on Solubility and Molecular Weight of Water-Soluble Arabinoxylan
Authors: Abdulmannan Fadel
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Arabinoxylan is a non-starch polysaccharide (NSP), which is one of the most important polysaccharides contained within cereal grains. Wheat endosperm pentosan and rice bran contain a significant amount of arabinoxylan (7% in rice bran and 10-12% in wheat endosperm pentosan). Several methods have been used for arabinoxylan extraction with varying degrees of success e.g. enzymatic and alkaline treatment. Yet, the use of extrusion alone as a pre-treatment to increase the yield and reduce the molecular weight in wheat endosperm pentosan and rice bran has not been investigated. The samples (wheat pentosan and rice bran) were extruded using a Twin-screw extruder at a range of screw speeds (80 and 160 rpm) and barrel temperatures range (80 to 140°C) with a throughput of 30 Kg hr-1 and moisture content of 25%. Arabinoxylans were extracted with water and the extraction yield and molecular weight was determined using size exclusion high-pressure liquid chromatography system. It was found that increasing screw speed from 80 rpm to 160 rpm, did not effect the extraction yield (p < 0.05) of arabinoxylan from either the wheat endosperm pentosan or the rice bran. However, the molecular weight of the extracted arabinoxylans from pentosan was found to decrease with increasing screw speed in wheat endosperm pentosan. These low molecular weight arabinoxylans have been suggested as immunomodulators.Keywords: arabinoxylans, extrusion, wheat endosperm pentosan, rice bran
Procedia PDF Downloads 4075310 Stabilization of Expansive Soils with Polypropylene Fiber
Authors: Ali Sinan Soğancı
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Expansive soils are often encountered in many parts of the world, especially in arid and semi-arid fields. Such kind of soils, generally including active clay minerals in low water content, enlarge in volume by absorbing the water through the surface and cause a great harm to the light structures such as channel coating, roads and airports. The expansive soils were encountered on the path of Apa-Hotamış conveyance channel belonging to the State Hydraulic Works in the region of Konya. In the research done in this area, it is predicted that the soil has a swollen nature and the soil should be filled with proper granular equipment by digging the ground to 50-60 cm. In this study, for purpose of helping the other research to be done in the same area, it is thought that instead of replacing swollen soil with the granular soil, by stabilizing it with polypropylene fiber and using it its original place decreases effect of swelling percent, in this way the cost will be decreased. Therefore, a laboratory tests were conducted to study the effects of polypropylene fiber on swelling characteristics of expansive soil. Test results indicated that inclusion of fiber reduced swell percent of expansive soil. As the fiber content increased, the unconfined compressive strength was increased. Finally, it can be say that stabilization of expansive soils with polypropylene fiber is an effective method.Keywords: expansive soils, polypropylene fiber, stabilization, swelling percent
Procedia PDF Downloads 4685309 Entropy Generation Analysis of Cylindrical Heat Pipe Using Nanofluid
Authors: Morteza Ghanbarpour, Rahmatollah Khodabandeh
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In this study, second law of thermodynamic is employed to evaluate heat pipe thermal performance. In fact, nanofluids potential to decrease the entropy generation of cylindrical heat pipes are studied and the results are compared with experimental data. Some cylindrical copper heat pipes of 200 mm length and 6.35 mm outer diameter were fabricated and tested with distilled water and water based Al2O3 nanofluids with volume concentrations of 1-5% as working fluids. Nanofluids are nanotechnology-based colloidal suspensions fabricated by suspending nanoparticles in a base liquid. These fluids have shown potential to enhance heat transfer properties of the base liquids used in heat transfer application. When the working fluid undergoes between different states in heat pipe cycle the entropy is generated. Different sources of irreversibility in heat pipe thermodynamic cycle are investigated and nanofluid effect on each of these sources is studied. Both experimental and theoretical studies reveal that nanofluid is a good choice to minimize the entropy generation in heat pipe thermodynamic cycle which results in higher thermal performance and efficiency of the system.Keywords: heat pipe, nanofluid, thermodynamics, entropy generation, thermal resistance
Procedia PDF Downloads 4615308 Preparation and Characterization of Antifouling Polysulfone Flat Sheet Membrane by Phase Inversion
Authors: Bharti Saini, Sukanta K. Dash
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In this work polymeric Nanofiltration (NF) membranes of polysulfone (PSF) (average molecular weight of 22400 Da) were prepared using polyethylene glycol (PEG) (average molecular weight of 200 Da) as an organic additive and ZnCl2 as an inorganic additive. Dimethyl acetamide (DMAc) was used as the solvent, and Deionised water as nonsolvent. The membranes were prepared by phase inversion (immersion precipitation) method. PEG 200 and ZnCl2 in varying concentration are directly added into the casting solution of PSF and DMAc. PEG 200 was used in concentration varying from 0 to 10 % (w/w) in the solution of PSF and DMAc, while ZnCl2 is varied from 0 to 2% (w/w). Membranes were characterized for surface morphology, water uptake, porosity and contact angle, with respect to concentration of PEG and ZnCl2. It was observed that with the increase in additive PEG 200, the porosity and hence, hydrophilicity increase. As a result, the number of pores increases as justified by the SEM analysis as well. The study revealed that the synergistic effect of PEG with ZnCl2 is more effective, and the best results were produced by the solution containing 2% PEG 200 and 1% ZnCl2. It was inferred that with the increase in concentration of additives, the pore size goes on decreasing. The membranes obtained gradually move from microfiltration range to nanofiltration range, and this change is primarily brought about by the addition of ZnCl2.Keywords: membrane, phase inversion method, polysulfone, porous structure
Procedia PDF Downloads 2315307 Plot Scale Estimation of Crop Biophysical Parameters from High Resolution Satellite Imagery
Authors: Shreedevi Moharana, Subashisa Dutta
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The present study focuses on the estimation of crop biophysical parameters like crop chlorophyll, nitrogen and water stress at plot scale in the crop fields. To achieve these, we have used high-resolution satellite LISS IV imagery. A new methodology has proposed in this research work, the spectral shape function of paddy crop is employed to get the significant wavelengths sensitive to paddy crop parameters. From the shape functions, regression index models were established for the critical wavelength with minimum and maximum wavelengths of multi-spectrum high-resolution LISS IV data. Moreover, the functional relationships were utilized to develop the index models. From these index models crop, biophysical parameters were estimated and mapped from LISS IV imagery at plot scale in crop field level. The result showed that the nitrogen content of the paddy crop varied from 2-8%, chlorophyll from 1.5-9% and water content variation observed from 40-90% respectively. It was observed that the variability in rice agriculture system in India was purely a function of field topography.Keywords: crop parameters, index model, LISS IV imagery, plot scale, shape function
Procedia PDF Downloads 1595306 Effects of Raw Bee Propolis and Water or Ethanol Extract of Propolis on Performance, Immune System and Some Blood Parameters on Broiler Bredeers
Authors: Hasan Alp Sahin, Ergin Ozturk
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The effects of raw bee propolis (RP) and water (WEP) or ethanol (EEP) extract of propolis on growth performance, selected immune parameters (IgA, IgY and IgM) and some blood parameters such as aspartate aminotransferase, alanine aminotransferase, trygliceride, total protein, albumin, calcium, phosphorus, total antioxidant status and total oxidant status were determined. The study was conducted between 15th and 20th weeks (6 weeks) and used a total of 48 broiler breeder pullets (Ross-308). The broiler breeder in control group was fed diet without propolis whereas the birds in RP, WEP and EEP groups were fed diets with RP, WEP and EEP at the level of 1200, 400 and 400 ppm, respectively. All pullets were fed mash form diet with 15% crude protein and 2800 ME kcal/kg. All propolis forms had not a beneficial effect on any studied parameters compared to control group (P > 0.05). The results of the study indicated that both the level of the active matters supplied from the bee propolis has no enough beneficial effect on performance, some immune and blood parameters on broiler breeders or they did not have such a level that would cause a beneficial effect on these variables.Keywords: antioxidant, bee product , poultry breeders, growth performance, immune parameters, blood chemistry
Procedia PDF Downloads 2555305 Bioaccessibility of Vitamin A Nanoemulsion: Influence of Carrier Oil and Surfactant Concentration
Authors: R. N. Astya, E. S. Nugraha, S. P. Nurheni, Hoerudin
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Vitamin A deficiency remains to be among the major malnutrition problems in Indonesia. Vitamin A is a fat-soluble vitamin which renders it difficult to be fortified in water-based foods and beverages. Furthermore, its low solubility and stability in aqueous system may limit its bioaccessibility in the gastrointestinal tract. Nanoemulsification of vitamin A may solve these problems. The objective of this study was to investigate bioaccessibility of vitamin A (retinyl palmitate/RP) nanoemulsion as influenced by two types of carrier oil (Virgin Coconut Oil/VCO and corn oil/CO) and surfactant concentrations (polysorbate 20/Tween 20 3% and 6%). Oil in water (o/w) nanoemulsions of vitamin A was produced through a combination of high shear-high pressure homogenization technique. The results showed that RP-VCO nanoemulsions were 121.62 nm (3%) and 115.40 (6%) nm in particle size, whereas RP-CO nanoemulsions were 154.72 nm (3%) and 134.00 nm (6%) in particle size. As for VCO nanoemulsions, the bioaccessibility of vitamin A was shown to be 89.84% and 55.32%, respectively. On the other hand, CO nanoemulsions produced vitamin A bioaccessibility of 53.66% and 44.85%, respectively. In general, VCO nanoemulsions showed better bioaccessibility of vitamin A than CO nanoemulsions. In this study, RP-VCO nanoemulsion with 3% Tween 20 had the highest ζ-potential value (-26.5 mV) and produced the highest bioaccessibility of vitamin A (89.84%, P<0.05). Additionally, the vitamin A nanoemulsion was stable even for after a week of freeze and thaw treatment. Following the freeze and thaw treatment, the vitamin A nanoemulsion showed good stability without aggregation and separation. These results would be useful for designing effective vitamin A delivery systems for food and beverage applications.Keywords: bioaccessibility, carrier oil, surfactant, vitamin A nanoemulsion
Procedia PDF Downloads 2595304 Design Aspects for Developing a Microfluidics Diagnostics Device Used for Low-Cost Water Quality Monitoring
Authors: Wenyu Guo, Malachy O’Rourke, Mark Bowkett, Michael Gilchrist
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Many devices for real-time monitoring of surface water have been developed in the past few years to provide early warning of pollutions and so to decrease the risk of environmental pollution efficiently. One of the most common methodologies used in the detection system is a colorimetric process, in which a container with fixed volume is filled with target ions and reagents to combine a colorimetric dye. The colorimetric ions can sensitively absorb a specific-wavelength radiation beam, and its absorbance rate is proportional to the concentration of the fully developed product, indicating the concentration of target nutrients in the pre-mixed water samples. In order to achieve precise and rapid detection effect, channels with dimensions in the order of micrometers, i.e., microfluidic systems have been developed and introduced into these diagnostics studies. Microfluidics technology largely reduces the surface to volume ratios and decrease the samples/reagents consumption significantly. However, species transport in such miniaturized channels is limited by the low Reynolds numbers in the regimes. Thus, the flow is extremely laminar state, and diffusion is the dominant mass transport process all over the regimes of the microfluidic channels. The objective of this present work has been to analyse the mixing effect and chemistry kinetics in a stop-flow microfluidic device measuring Nitride concentrations in fresh water samples. In order to improve the temporal resolution of the Nitride microfluidic sensor, we have used computational fluid dynamics to investigate the influence that the effectiveness of the mixing process between the sample and reagent within a microfluidic device exerts on the time to completion of the resulting chemical reaction. This computational approach has been complemented by physical experiments. The kinetics of the Griess reaction involving the conversion of sulphanilic acid to a diazonium salt by reaction with nitrite in acidic solution is set in the Laminar Finite-rate chemical reaction in the model. Initially, a methodology was developed to assess the degree of mixing of the sample and reagent within the device. This enabled different designs of the mixing channel to be compared, such as straight, square wave and serpentine geometries. Thereafter, the time to completion of the Griess reaction within a straight mixing channel device was modeled and the reaction time validated with experimental data. Further simulations have been done to compare the reaction time to effective mixing within straight, square wave and serpentine geometries. Results show that square wave channels can significantly improve the mixing effect and provides a low standard deviations of the concentrations of nitride and reagent, while for straight channel microfluidic patterns the corresponding values are 2-3 orders of magnitude greater, and consequently are less efficiently mixed. This has allowed us to design novel channel patterns of micro-mixers with more effective mixing that can be used to detect and monitor levels of nutrients present in water samples, in particular, Nitride. Future generations of water quality monitoring and diagnostic devices will easily exploit this technology.Keywords: nitride detection, computational fluid dynamics, chemical kinetics, mixing effect
Procedia PDF Downloads 1955303 Spatial Analysis in the Impact of Aquifer Capacity Reduction on Land Subsidence Rate in Semarang City between 2014-2017
Authors: Yudo Prasetyo, Hana Sugiastu Firdaus, Diyanah Diyanah
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The phenomenon of the lack of clean water supply in several big cities in Indonesia is a major problem in the development of urban areas. Moreover, in the city of Semarang, the population density and growth of physical development is very high. Continuous and large amounts of underground water (aquifer) exposure can result in a drastically aquifer supply declining in year by year. Especially, the intensity of aquifer use in the fulfilment of household needs and industrial activities. This is worsening by the land subsidence phenomenon in some areas in the Semarang city. Therefore, special research is needed to know the spatial correlation of the impact of decreasing aquifer capacity on the land subsidence phenomenon. This is necessary to give approve that the occurrence of land subsidence can be caused by loss of balance of pressure on below the land surface. One method to observe the correlation pattern between the two phenomena is the application of remote sensing technology based on radar and optical satellites. Implementation of Differential Interferometric Synthetic Aperture Radar (DINSAR) or Small Baseline Area Subset (SBAS) method in SENTINEL-1A satellite image acquisition in 2014-2017 period will give a proper pattern of land subsidence. These results will be spatially correlated with the aquifer-declining pattern in the same time period. Utilization of survey results to 8 monitoring wells with depth in above 100 m to observe the multi-temporal pattern of aquifer change capacity. In addition, the pattern of aquifer capacity will be validated with 2 underground water cavity maps from observation of ministries of energy and natural resources (ESDM) in Semarang city. Spatial correlation studies will be conducted on the pattern of land subsidence and aquifer capacity using overlapping and statistical methods. The results of this correlation will show how big the correlation of decrease in underground water capacity in influencing the distribution and intensity of land subsidence in Semarang city. In addition, the results of this study will also be analyzed based on geological aspects related to hydrogeological parameters, soil types, aquifer species and geological structures. The results of this study will be a correlation map of the aquifer capacity on the decrease in the face of the land in the city of Semarang within the period 2014-2017. So hopefully the results can help the authorities in spatial planning and the city of Semarang in the future.Keywords: aquifer, differential interferometric synthetic aperture radar (DINSAR), land subsidence, small baseline area subset (SBAS)
Procedia PDF Downloads 1725302 Field Deployment of Corrosion Inhibitor Developed for Sour Oil and Gas Carbon Steel Pipelines
Authors: Jeremy Moloney
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A major oil and gas operator in western Canada producing approximately 50,000 BOE per day of sour fluids was experiencing increased water production along with decreased oil production over several years. The higher water volumes being produced meant an increase in the operator’s incumbent corrosion inhibitor (CI) chemical requirements but with reduced oil production revenues. Thus, a cost-effective corrosion inhibitor solution was sought to deliver enhanced corrosion mitigation of the carbon steel pipeline infrastructure but at reduced chemical injection dose rates. This paper presents the laboratory work conducted on the development of a corrosion inhibitor under the operator’s simulated sour operating conditions and then subsequent field testing of the product. The new CI not only provided extremely good levels of general and localized corrosion inhibition and outperformed the incumbent CI under the laboratory test conditions but did so at vastly lower concentrations. In turn, the novel CI product facilitated field chemical injection rates to be optimized and reduced by 40% compared with the incumbent whilst maintaining superior corrosion protection resulting in significant cost savings and associated sustainability benefits for the operator.Keywords: carbon steel, sour gas, hydrogen sulphide, localized corrosion, pitting, corrosion inhibitor
Procedia PDF Downloads 715301 Genotoxicity of 4-Nonylphenol (4NP) on Oreochromus spilurs Fish
Authors: M. M. Alsharif
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4-Nonylphenol Compound is widely used as an element of detergents, paints, insecticides and many others products. It is known that the existence of this compound may lead to the emission of estrogenic responses in mammals, birds and fish. It is described as pollutant since it causes disorder of endocrine glands. In previous studies, it was proven that this compound exists in water and in the materials precipitated in Red Sea coast in Jeddah near the drains of processed drainage water and near the drainage site of the residuals of paper factories. Therefore, this study aimed to evaluate the cytogenetic aberrations caused by 4-nonylphenol through exposing Talapia Fishes to aquatic solution of the compound with 0, 15, 30 microgram/liter for one month. Samples of gills and liver were collected for micronuclei, nuclear abnormalities and measuring DNA and RNA amount in the treated fish. The results pointed out that there is a significant increase in the numbers of micronuclei in the fish exposed to the former concentrations as compared to the control group. Exposing fishes to 4-nonylphenol resulted in an increased amount of both DNA and RNA, compared to the control group. There is a positive correlation between the amount of the compound (i.e. dosage dependent effect) and the inspiring for cytogenetic effect on Talapia fishes in Jeddah. Therefore, micronucleus test, DNA and RNA contents can be considered as an index of cumulative exposure, which appear to be a sensitive model to evaluate genotoxic effects of 4-Nonylphenol compound on fish.Keywords: genotoxic, 4-nonylphenol, micronuclei, fish, DNA, RNA
Procedia PDF Downloads 3025300 Experimental Study on Recycled Aggregate Pervious Concrete
Authors: Ji Wenzhan, Zhang Tao, Li Guoyou
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Concrete is the most widely used building material in the world. At the same time, the world produces a large amount of construction waste each year. Waste concrete is processed and treated, and the recycled aggregate is used to make pervious concrete, which enables the construction waste to be recycled. Pervious concrete has many advantages such as permeability to water, protection of water resources, and so on. This paper tests the recycled aggregate obtained by crushing high-strength waste concrete (TOU) and low-strength waste concrete (PU), and analyzes the effect of porosity, amount of cement, mineral admixture and recycled aggregate on the strength of permeable concrete. The porosity is inversely proportional to the strength, and the amount of cement used is proportional to the strength. The mineral admixture can effectively improve the workability of the mixture. The quality of recycled aggregates had a significant effect on strength. Compared with concrete using "PU" aggregates, the strength of 7d and 28d concrete using "TOU" aggregates increased by 69.0% and 73.3%, respectively. Therefore, the quality of recycled aggregates should be strictly controlled during production, and the mix ratio should be designed according to different use environments and usage requirements. This test prepared a recycled aggregate permeable concrete with a compressive strength of 35.8 MPa, which can be used for light load roads and provides a reference for engineering applications.Keywords: recycled aggregate, permeable concrete, compressive strength, permeability
Procedia PDF Downloads 2105299 Groundwater Quality Assessment in the Vicinity of Tannery Industries in Warangal, India
Authors: Mohammed Fathima Shahanaaz, Shaik Fayazuddin, M. Uday Kiran
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Groundwater quality is deteriorating day by day in different parts of the world due to various reasons, toxic chemicals are being discharged without proper treatment into inland water bodies and land which in turn add pollutants to the groundwater. In this kind of situation, the rural communities which do not have municipal drinking water have to rely on groundwater though it is polluted for various uses. Tannery industry is one of the major industry which provides economy and employment to India. Since most of the developed countries stopped using chemicals which are toxic, the tanning industry which uses chromium as its major element are being shifted towards developing countries. Most of the tanning industries in India can be found in clusters concentrated mainly in states of Tamilnadu, West Bengal, Uttar Pradesh and limited places of Punjab. Limited work is present in the case of tanneries of Warangal. There exists 18 group of tanneries in Desaipet, Enamamula region of Warangal, out of which 4 are involved in dry process and are low responsible for groundwater pollution. These units of tanneries are discharging their effluents after treatment into Sai Cheruvu. Though the treatment effluents are being discharged, the Sai Cheruvu is turned in to Pink colour, with higher levels of BOD, COD, chromium, chlorides, total hardness, TDS and sulphates. An attempt was made to analyse the groundwater samples around this polluted Sai Cheruvu region since literature shows that a single tannery can pollute groundwater to a radius of 7-8 kms from the point of disposal. Sample are collected from 6 different locations around Sai Cheruvu. Analysis was performed for determining various constituents in groundwater such as pH, EC, TDS, TH, Ca+2, Mg+2, HCO3-, Na+, K+, Cl-, SO42-, NO3-, F and Cr+6. The analysis of these constitutes gave values greater than permissible limits. Even chromium is also present in groundwater samples which is exceeding permissible limits People in Paidepally and Sardharpeta villages already stopped the usage of groundwater. They are buying bottle water for drinking purpose. Though they are not using groundwater for drinking purpose complaints are made about using this water for washing also. So treatment process should be adopted for groundwater which should be simple and efficient. In this study rice husk silica (RHS) is used to treat pollutants in groundwater with varying dosages of RHS and contact time. Rice husk is treated, dried and place in a muffle furnace for 6 hours at 650°C. Reduction is observed in total hardness, chlorides and chromium levels are observed after the application RHS. Pollutants reached permissible limits for 27.5mg/l and 50 mg/l of dosage for a contact time of 130 min at constant pH and temperature.Keywords: chromium, groundwater, rice husk silica, tanning industries
Procedia PDF Downloads 1945298 Examination of Woody Taxa in Urban Parks in the Context of Climate Change: Resat Oyal Kulturpark and Hudavendigar Urban Park Samples
Authors: Murat Zencirkıran, Elvan Ender
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Climate change, which has become effective on a global scale, is accompanied by an increase in negative conditions for human, plant and animal life. Especially these negative conditions (drought, warming, glowing, etc.) are felt more rapidly in urban life and affect the sustainability of green areas which are of great importance in terms of life comfort. In this context, the choice of woody taxa used in the design and design of green spaces in the city increase one more time. Within the scope of this study, two of four urban parks located in the city center of Bursa province were selected and evaluated for woody taxa. Urban parks have been identified as the oldest and newest urban park in Bursa, and it has been tried to emphasize the differences that may exist over time. It was determined that 54 woody taxa took place in Resat Oyal Kulturpark and 76 woody taxa in Hudavendigar Urban Park. These taxa have been evaluated in terms of water consumption and ecological tolerances by taking into account climate change, and suggestions have been developed against possible problems.Keywords: ecological hardiness, urban park, water consumption, woody plants
Procedia PDF Downloads 2925297 In situ Immobilization of Mercury in a Contaminated Calcareous Soil Using Water Treatment Residual Nanoparticles
Authors: Elsayed A. Elkhatib, Ahmed M. Mahdy, Mohamed L. Moharem, Mohamed O. Mesalem
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Mercury (Hg) is one of the most toxic and bio-accumulative heavy metal in the environment. However, cheap and effective in situ remediation technology is lacking. In this study, the effects of water treatment residuals nanoparticles (nWTR) on mobility, fractionation and speciation of mercury in an arid zone soil from Egypt were evaluated. Water treatment residual nanoparticles with high surface area (129 m 2 g-1) were prepared using Fritsch planetary mono mill. Scanning and transmission electron microscopy revealed that the nanoparticles of WTR nanoparticles are spherical in shape, and single particle sizes are in the range of 45 to 96 nm. The x-ray diffraction (XRD) results ascertained that amorphous iron, aluminum (hydr)oxides and silicon oxide dominating all nWTR, with no apparent crystalline iron–Al (hydr)oxides. Addition of nWTR, greatly increased the Hg sorption capacities of studied soils and greatly reduced the cumulative Hg released from the soils. Application of nWTR at 0.10 and 0.30 % rates reduced the released Hg from the soil by 50 and 85 % respectively. The power function and first order kinetics models well described the desorption process from soils and nWTR amended soils as evidenced by high coefficient of determination (R2) and low SE values. Application of nWTR greatly increased the association of Hg with the residual fraction. Meanwhile, application of nWTR at a rate of 0.3% greatly increased the association of Hg with the residual fraction (>93%) and significantly increased the most stable Hg species (Hg(OH)2 amor) which in turn enhanced Hg immobilization in the studied soils. Fourier transmission infrared spectroscopy analysis indicated the involvement of nWTR in the retention of Hg (II) through OH groups which suggest inner-sphere adsorption of Hg ions to surface functional groups on nWTR. These results demonstrated the feasibility of using a low-cost nWTR as best management practice to immobilize excess Hg in contaminated soils.Keywords: release kinetics, Fourier transmission infrared spectroscopy, Hg fractionation, Hg species
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