Search results for: urban water resilience
2640 The Effect of Supercritical Fluid on the Extraction Efficiency of Heavy Metal from Soil
Authors: Haifa El-Sadi, Maria Elektorowicz, Reed Rushing, Ammar Badawieh, Asif Chaudry
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Clay soils have particular properties that affect the assessment and remediation of contaminated sites. In clay soils, electro-kinetic transport of heavy metals has been carried out. The transport of these metals is predicated on maintaining a low pH throughout the cell, which, in turn, keeps the metals in the pore water phase where they are accessible to electro-kinetic transport. Supercritical fluid extraction and acid digestion were used for the analysis of heavy metals concentrations after the completion of electro-kinetic experimentation. Supercritical fluid (carbon dioxide) extraction is a new technique used to extract the heavy metal (lead, nickel, calcium and potassium) from clayey soil. The comparison between supercritical extraction and acid digestion of different metals was carried out. Supercritical fluid extraction, using ethylenediaminetetraacetic acid (EDTA) as a modifier, proved to be efficient and a safer technique than acid digestion technique in extracting metals from clayey soil. Mixing time of soil with EDTA before extracting heavy metals from clayey soil was investigated. The optimum and most practical shaking time for the extraction of lead, nickel, calcium and potassium was two hours.Keywords: clay soil, heavy metals, supercritical fluid extraction, acid digestion
Procedia PDF Downloads 4642639 Three Dimensional Model of Full Scale Plate Load Test on Stone Column in Sabkha Deposit: Case Study from Jubail Industrial City - Saudi Arabia
Authors: Hassan. A. Abas, Saad A. Aiban
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Soil improvement by means of stone column method is used to improve sabkha soils in order to limit total and differential settlement and to achieve the required bearing capacity. Full-scale plate test was performed on site to confirm the achievement of required bearing capacity at the specified settlement. Despite the fact that this technique is widely used to improve sabkha soils, there are no studies focusing on the behavior of stone columns in such problematic soils. Sabkha soils are known for its high compressibility, low strength and water sensitivity due to loss of salt cementation upon flooding during installation of stone columns. Numerical modeling of plate load test assist to understand complicated behavior of sabkha – stone column interaction. This paper presents a three-dimensional Finite element model, using PLAXIS 3D software, to simulate vertical plate load tests on a stone column installed in sabkha. The predicted settlement values are in reasonable agreement with the field measure values and the field load - settlement curve can be predicted with good accuracy.Keywords: soil improvement, stone column, sabkha, PLAXIS 3D
Procedia PDF Downloads 3872638 Antioxidant Potential of Methanolic Extracts of Four Indian Aromatic Plants
Authors: Harleen Kaur, Richa
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Plants produce a large variety of secondary metabolites. Phenolics are the compounds that contain hydroxyl functional group on an aromatic ring. These are chemically heterogeneous compounds. Some are soluble only in organic solvents, some are water soluble and others are large insoluble polymers. Flavonoids are one of the largest classes of plant phenolics. The carbon skeleton of a flavonoid contains 15 carbons arranged in two aromatic rings connected by a three carbon ridge. Both phenolics and flavonoids are good natural antioxidants. Four Indian aromatic plants were selected for the study i.e, Achillea species, Jasminum primulinum, Leucas cephalotes and Leonotis nepetaefolia. All the plant species were collected from Chail region of Himachal Pradesh, India. The identifying features and anatomical studies were done of the part containing the essential oils. Phenolic cotent was estimated by Folin Ciocalteu’s method and flavonoids content by aluminium chloride method. Antioxidant property was checked by using DPPH method. Maximum antioxidant potential was found in Achillea species, followed by Leonotis nepetaefolia, Jaminum primulinum and Leucas cephalotes. Phenolics and flavonoids are important compounds that serve as defences against herbivores and pathogens. Others function in attracting pollinators and absorbing harmful radiations.Keywords: antioxidants, DPPH, flavonoids, phenolics
Procedia PDF Downloads 3462637 Study of Tribological Behavior of Zirconium Alloy Against SS-410 at High Temperature
Authors: Bharat Kumar, Deepak Kumar, Vijay Chaudhry
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Zirconium alloys exhibit low neutron absorption cross-section and excellent mechanical properties. Due to these unique characteristics, these materials are widely used in designing core components of pressurized heavy water reactors (PHWRs). Another material that is widely used in the design of reactor core is stainless steel. Under operating conditions of the reactor, there are possibilities for mechanical and tribological interaction between the components made of zirconium alloy (Zr-2.5 Nb) and stainless steel (SS-410). This may result in wear of the material. To study the tribological characteristics of Zr-2.5 Nb and SS-410, low amplitude reciprocating wear tests are conducted at room temperature and at high temperatures (260 degrees Celsius). The tests are conducted at frequencies ranging from 5 Hz to 25 Hz. The displacement amplitude is varied from 200 µm to 600 µm. The responses are recorded, analyzed and correlated with damage observed using scanning electron microscopy (SEM) and an optical profilometer. Energy dispersive spectroscopy (EDS) is used to study the damage mechanism prevailing at the contact interface. A higher coefficient of friction (COF) is observed at higher temperatures as compared to the one at room temperature. Tests carried out at high temperature reveals adhesive wear as the dominant mechanism resulting in significant material transfer.Keywords: PHWRs, Zr-2.5Nb, SS-410, wear
Procedia PDF Downloads 902636 Geochemical Evaluation of Weathering-Induced Release of Trace Metals from the Maastritchian Shales in Parts of Bida an Anambra Basins, Nigeria
Authors: Adetunji Olusegun Aderigibigbe
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Shales, especially black shales, are of great geological significance, in the study of heavy/trace metal contamination. This is due to their abundance in occurrence and high concentration of heavy metals embedded which are released during their weathering. Heavy metals constitute one of the most dangerous pollution known to human because they are toxic (i.e., carcinogenic), non-biodegradable and can enter the global eco-biological circle. In the past, heavy metal contamination in aquatic environment and agricultural top soil has been attributed to industrial wastes, mining extractions and pollution from traffic vehicles; only a few studies have focused on weathering of shale as possible source of heavy metal contamination. Based on the above background, this study attempts to establish weathering of shale as possible source of trace/heavy metal contaminations. This was done by carefully selecting fresh and their corresponding weathered shale samples from selected localities in Bida and Anambra Basins. The samples were analysed in Activation Laboratories Ltd; Ontario, Canada for trace/heavy metal. It was observed that some major and trace metals were released during weathering, i.e., some were depleted and some enriched. By this contamination of water zones and agricultural top soils are not only traceable to biogenic processes but geogenic inputs (weathering of shale) as well.Keywords: contamination, fresh samples, heavy metals, pollution, shales, trace metals, weathered samples
Procedia PDF Downloads 1312635 Numerical Simulation of Fluid-Structure Interaction on Wedge Slamming Impact by Using Particle Method
Authors: Sung-Chul Hwang, Di Ren, Sang-Moon Yoon, Jong-Chun Park, Abbas Khayyer, Hitoshi Gotoh
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The slamming impact problem has a very important engineering background. For seaplane landing, recycling for the satellite re-entry capsule, and the impact load of the bow in the adverse sea conditions, the slamming problem always plays the important role. Due to its strong nonlinear effect, however, it seems to be not easy to obtain the accurate simulation results. Combined with the strong interaction between the fluid field and the elastic structure, the difficulty for the simulation leads to a new level for challenging. This paper presents a fully Lagrangian coupled solver for simulations of fluid-structure interactions, which is based on the Moving Particle Semi-implicit (MPS) method to solve the governing equations corresponding to incompressible flows as well as elastic structures. The developed solver is verified by reproducing the high velocity impact loads of deformable thin wedges with two different materials such as aluminum and steel on water entry. The present simulation results are compared with analytical solution derived using the hydrodynamic Wagner model and linear theory by Wan.Keywords: fluid-structure interaction, moving particle semi-implicit (MPS) method, elastic structure, incompressible flow, wedge slamming impact
Procedia PDF Downloads 6012634 Methane Production from Biomedical Waste (Blood)
Authors: Fatima M. Kabbashi, Abdalla M. Abdalla, Hussam K. Hamad, Elias S. Hassan
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This study investigates the production of renewable energy (biogas) from biomedical hazard waste (blood) and eco-friendly disposal. Biogas is produced by the bacterial anaerobic digestion of biomaterial (blood). During digestion process bacterial feeding result in breaking down chemical bonds of the biomaterial and changing its features, by the end of the digestion (biogas production) the remains become manure as known. That has led to the economic and eco-friendly disposal of hazard biomedical waste (blood). The samples (Whole blood, Red blood cells 'RBCs', Blood platelet and Fresh Frozen Plasma ‘FFP’) are collected and measured in terms of carbon to nitrogen C/N ratio and total solid, then filled in connected flasks (three flasks) using water displacement method. The results of trails showed that the platelet and FFP failed to produce flammable gas, but via a gas analyzer, it showed the presence of the following gases: CO, HC, CO₂, and NOX. Otherwise, the blood and RBCs produced flammable gases: Methane-nitrous CH₃NO (99.45%), which has a blue color flame and carbon dioxide CO₂ (0.55%), which has red/yellow color flame. Methane-nitrous is sometimes used as fuel for rockets, some aircraft and racing cars.Keywords: renewable energy, biogas, biomedical waste, blood, anaerobic digestion, eco-friendly disposal
Procedia PDF Downloads 3002633 Study of Petroleum Hydrocarbons Biodegradation and the Role of Biosurfactants Produced by Bacteria Isolated from the Lagoon of Mar Chica in This Process
Authors: Ikram Kamal, Mohamed Blaghen
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Petroleum hydrocarbons are serious problems and global pollutants in the environment due to their toxicity, carcinogenicity and persistent organic pollutant properties. One of the approaches to enhance biodegradation of petroleum hydrocarbons is to use biosurfactant. Biosurfactants are amphiphilic biomolecules produced as metabolic by-products from microorganisms they received considerable attention in the field of environmental remediation processes such as bioremediation. Biosurfactants have been considered as a desirable alternative to synthetic surfactants in various applications particularly in the environmental field. In comparison with their synthetic counterparts, biosurfactants have been reported to be less toxic, biodegradable and persistent. In this study we have investigated the potential of bacterial strains collected aseptically from the lagoon Marchika (water and soil) in Nador, Morocco; for the production of biosurfactants. This study also aimed to optimize the biosurfactant production process by changing the variables that influence the type and amount of biosurfactant produced by these microorganisms such as: carbon sources and also other physical and chemical parameters such as temperature and pH. Emulsification index, methylene blue test and thin layer chromatography (TLC) revealed the ability of strains used in this study to produce compounds that could emulsify gasoline. In addition, a HPLC/MS was used to separate and identify different biosurfactants purified.Keywords: petroleum hydrocarbons, biosurfactants, biodegradation, lagoon marchika, emulsification index
Procedia PDF Downloads 2592632 Green Catalytic Conversion of Some Aromatic Alcohols to Acids by NiO₂ Nanoparticles (NPNPs) in Water
Authors: Abdel Ghany F. Shoair, Mai M. A. H. Shanab
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The basic aqueous systems NiSO4.6H₂O / K₂S₂O₈ (PH= 14) or NiSO₄.6H₂O / KBrO₃ (PH = 11.5) were investigated for the catalytic conversion benzyl alcohol and some para-substituted benzyl alcohols to their corresponding acids in 75-97 % yield at room temperature. The active species was isolated and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction, EDX and FT-IR techniques and identified as NiO₂ nanoparticles (NPNPs). The SEM and TEM images of nickel peroxide samples show a fine spherical-like aggregation of NiO₂ molecules with a nearly homogeneous partial size and confirm the aggregation's size to be in the range of 2-3 nm. The yields, turnover (TO) and turn over frequencies (TOF) were calculated. It was noticed that the aromatic alcohols containing para-substituted electron donation groups gave better yields than those having electron-withdrawing groups. The optimum conditions for this catalytic reaction were studied using benzyl alcohol as a model. The mechanism of the catalytic conversion reaction was suggested, in which the produced (NPNPs) convert alcohols to acids in two steps through the formation of the corresponding aldehyde. The produced NiO, because of this conversion, is converted again to (NPNPs) by an excess of K₂S₂O₈ or KBrO₃. This catalytic cycle continues until all the substrate is oxidized.Keywords: Nickel, oxidation, catalysts, benzyl alcohol
Procedia PDF Downloads 752631 Formulation and Evaluation of Mouth Dissolving Tablet of Ketorolac Tromethamine by Using Natural Superdisintegrants
Authors: J. P. Lavande, A. V.Chandewar
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Mouth dissolving tablet is the speedily growing and highly accepted drug delivery system. This study was aimed at development of Ketorolac Tromethamine mouth dissolving tablet (MDTs), which can disintegrate or dissolve rapidly once placed in the mouth. Conventional Ketorolac tromethamine tablet requires water to swallow it and has limitation like low disintegration rate, low solubility etc. Ketorolac Tromethamine mouth dissolving tablets (formulation) consist of super-disintegrate like Heat Modified Karaya Gum, Co-treated Heat Modified Agar & Filler microcrystalline cellulose (MCC). The tablets were evaluated for weight variation, friability, hardness, in vitro disintegration time, wetting time, in vitro drug release profile, content uniformity. The obtained results showed that low weight variation, good hardness, acceptable friability, fast wetting time. Tablets in all batches disintegrated within 15-50 sec. The formulation containing superdisintegrants namely heat modified karaya gum and heat modified agar showed better performance in disintegration and drug release profile.Keywords: mouth dissolving tablet, Ketorolac tromethamine, disintegration time, heat modified karaya gum, co-treated heat modified agar
Procedia PDF Downloads 2802630 Evaluation of Moroccan Microalgae Spirulina platensis as a Potential Source of Natural Antioxidants
Authors: T. Ould Bellahcen, A. Amiri, I. Touam, F. Hmimid, A. El Amrani, M. Cherki
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The antioxidant activity of three extracts (water, lipidic and ethanolic) prepared from the microalgae Spirulina platensis isolated from Moroccan lake, using 2, 2 diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis ethylbenzthiazoline-6-sulfonic acid (ABTS) radical assay, was studied and compared. The obtained results revealed that the IC₅₀ found using DPPH were lower than that of ABTS for all extracts from these planktonic blue-green algae. The high levels of phenolic and flavonoid content were found in the ethanolic extract 0,33 ± 0,01 mg GAE/g dw and 0,21 ± 0,01 mg quercetin/g dw respectively. In addition, using DPPH, the highest activity with IC₅₀ = 0,449 ± 0,083 mg/ml, was found for the ethanolic extract, followed by that of lipidic extract (IC₅₀ = 0,491 ± 0,059 mg/ml). The lowest activity was for the aqueous extract (IC₅₀ = 4,148 ± 0,132 mg/ml). For ABTS, the highest activity was observed for the lipidic extract with IC₅₀ = 0,740 ± 0,012 mg/ml, while, the aqueous extract recorded the lowest activity (IC₅₀ = 6,914 ± 0, 0067 mg/ml). A moderate activity was showed for the ethanolic extract (IC₅₀ = 5,852 ± 0, 0171 mg/ml). It can be concluded from this first study that Spirulina platensis extracts show an interesting antioxidant and antiradicals properties suggesting that this alga could be used as a potential source of antioxidants. A qualitative and quantitative analysis of polyphenol and flavonoids in the extracts using HPLC is in progress so as to study the correlation between the antioxidant activity and chemical composition.Keywords: Spirulina platensis, antioxidant, DPPH, ABTS
Procedia PDF Downloads 1642629 Photocatalytic Degradation of Methylene Blue Dye Using Pure and Ag-Doped SnO₂ Nanoparticles as Catalyst
Authors: M. S. Abd El-Sadek, Mahmoud A. Omar, Gharib M. Taha
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Photodegradation of methylene blue in the presence of tin dioxide (SnO₂) nanoparticles under solar light irradiation are known to be an effective photocatalytic process. In this study, pure and silver (Ag) doped tin dioxide (SnO₂) nanoparticles were prepared at calcination temperature (800ºC) by a modified sol-gel method and studied for their photocatalytic activity with methylene blue as a test contaminant. The characterization of undoped and doped SnO₂ photocatalyst was studied by X-rays diffraction patterns (XRD), transmission electron microscopy (TEM), Fourier Transform Infrared Spectroscopy (FT-IR) and Energy Dispersive X-ray Microanalysis (EDX). The catalytic degradation of methylene blue in aqueous media was studied using UV-Vis spectrophotometer to monitor the degradation process by measuring its absorption spectra. The main absorption peak of methylene blue is observed at λ= 664 nm. The change in the percent of silver in the catalyst affects the photoactivity of SnO₂ on the degradation of methylene blue. The photoactivity of pure SnO₂ was found to be a maximum at dose 0.2 gm of the catalyst with 100 ml of 5 ppm methylene blue in the water. Within 210 min of photodegradation (under sunlight) after leaving the reaction for 90 minutes in the dark to avoid the effect of adsorption, the pure SnO₂ at calcination temperature 800ºC exhibited the best photocatalytic degradation with removal percentage of 93.66% on methylene blue degradation under solar light.Keywords: SnO₂ nanoparticles, methylene blue degradation, photocatalysis, silver doped-SnO₂
Procedia PDF Downloads 1402628 Antibacterial Activity of the Essential Oil of Origanum glandulosum on Bacterial Strains of Hospital Origin Most Implicated in Nosocomial Infections
Authors: A. Lardjam, R. Mazid, S. Y. Boudghene, A. Izarouken, Y. Dali, N. Djebli, H. Toumi
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Origanum glandulosum is an aromatic plant, common in Algeria and widely used by local people for its medicinal properties. The essential oil from this plant, which grows in the west of Algeria, was studied to evaluate and determine its antibacterial activity. The extraction of the essential oil was performed by water steam distillation; the yield obtained from the aerial parts (1.78 %) is interesting, its chromatographic profile revealed by TLC showed the presence of phenolic compounds thymol and carvacrol. The evaluation of the activity of the essential oil of Origanum glandulosum on bacterial strains of hospital origin, ATCC, MRB, and HRB, most implicated in nosocomial infections (Staphylococcus aureus ATCC 25923, Staphylococcus aureus ATCC 43300, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus resistant to meticillin, Enterococcus faecium, VA R and R TEC, Acinetobacter baumanii, IMP R and R CAZ, Klebsiella pneumonia carbapenemase-producing) by the method of aromatogramme and micro atmosphere, shows that the antibacterial potency of this oil is very high, expressed by significant inhibition diameters on all strains except Pseudomonas aeruginosa, and low MICs and is characterized by a bactericidal action.Keywords: antibacterial activity, essential oil, HRB, MBR, nosocomial infections, origanum glandulosum
Procedia PDF Downloads 3202627 Modification of a Natural Zeolite with a Short-Chain Quaternary Ammonium Salt in an Ultrasonication Process and Investigation of Its Ability to Eliminate Nitrate Ions: Characterization and Mechanism Study
Authors: Nona Mirzamohammadi, Bahram Nasernejad
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This work mainly focuses on studying the mechanism governing the adsorption of tetraethylammonium bromide, a short-chain quaternary ammonium salt, on the surface of natural zeolite and to characterize modified and raw zeolites in order to study the removal of nitrate anions from water. Natural clinoptilolite, as the most common zeolite, was chosen and modified in an ultrasonication process using tetraethylammonium bromide, subsequent to being contacted with NaCl solutions. FT-IR studies indicated a peak attributed to the stretching vibrations of the –CH₂ group in the molecule of tetraethylammonium bromide in the spectrum of the modified sample. Moreover, the SEM images showed some obvious changes in the surface morphology and crystallinity of clinoptilolite after being modified. Batch adsorption experiments show that the modified zeolite is capable of removing nitrate anions, and the predominant removal mechanism is suggested to be a combination of electrostatic attraction and ion exchange since the results from the zeta potential analysis showed a decrease in the net negative charge of clinoptilolite after modification, while bromide ions were detected in the modified sample in the µXRF analysis.Keywords: adsorption, clinoptilolite, short-chain quaternary ammonium salt, tetraethylammoniumbromide, ultrasonication
Procedia PDF Downloads 1052626 Cesium 137 Leaching from Soils of Territories, Polluted by Radionuclides
Authors: S. V. Vasilenkov, O. N. Demina
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Chernobyl NPP accident is the biggest in history of nuclear energetic. Bryansk region of Russia was exposed by the most intensive radiation pollution. For that, we made some researches in order to find the methods of soil rehabilitation on territories, polluted by radionuclides with the means of Cesium 137 leaching by watering. For experiments we took the soil from the upper more polluted 10 cm layer of different species. Cesium 137 leaching was made by different methods in washing columns. Washout of Cesium was made by periodical cycles in terms of 4-6 days. In experiments with easy argillaceous soil with start specific radioactivity 4158 bk/kg through 17 cycles the effective reducing was achieved and contained 1512 bk/kg. Besides, results of researches showed, that in the first 6-10 cycles we can see reducing of washing rate but after application of intensificators: ultrasound water processing, aerification, application of fertilizers (KCl), lime, freezing, we can see increasing of Cesium 137 leaching. The experimental investigations in washout of Cesium (Cs) – 137 from the soil were carried out in the field and laboratorial conditions during its freezing and melting. The experiments showed, that washout of Cesium (Cs) – 137 from the soil is rather high after freezing, than non-frozen soil is. And it conforms to washout of Cesium, made under the influence of the intensificaters. This fact allows to recommend chip and easy to construct technically arrangement for regulation of the snow-melt runoff for rehabilitation of the radioactive impoundment.Keywords: pollution, radiation, Cesium 137 leaching, agriculture
Procedia PDF Downloads 2912625 Field Tests and Numerical Simulation of Tunis Soft Soil Improvement Using Prefabricated Vertical Drains
Authors: Marwa Ben Khalifa, Zeineb Ben Salem, Wissem Frikha
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This paper presents a case study of “Radès la Goulette” bridge project using the technique of prefabricated vertical drains (PVD) associated with step by step construction of preloading embankments with averaged height of about 6 m. These embankments are founded on a highly compressible layer of Tunis soft soil. The construction steps included extensive soil instrumentation such as piezometers and settlement plates for monitoring the dissipation of excess pore water pressures and settlement during the consolidation of Tunis soft soil. An axisymmetric numerical model using the 2D finite difference code FLAC was developed and calibrated using laboratory tests to predict the soil behavior and consolidation settlements. The constitutive model impact for simulating the soft soil behavior is investigated. The results of analyses show that numerical analysis provided satisfactory predictions for the field performance during the construction of Radès la Goulette embankment. The obtained results show the effectiveness of PVD in the acceleration of the consolidation time. A comparison of numerical results with theoretical analysis was presented.Keywords: tunis soft soil, radès bridge project, prefabricated vertical drains, FLAC, acceleration of consolidation
Procedia PDF Downloads 1212624 Investigating the Atmospheric Phase Distribution of Inorganic Reactive Nitrogen Species along the Urban Transect of Indo Gangetic Plains
Authors: Reema Tiwari, U. C. Kulshrestha
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As a key regulator of atmospheric oxidative capacity and secondary aerosol formations, the signatures of reactive nitrogen (Nr) emissions are becoming increasingly evident in the cascade of air pollution, acidification, and eutrophication of the ecosystem. However, their accurate estimates in N budget remains limited by the photochemical conversion processes where occurrence of differential atmospheric residence time of gaseous (NOₓ, HNO₃, NH₃) and particulate (NO₃⁻, NH₄⁺) Nr species becomes imperative to their spatio temporal evolution on a synoptic scale. The present study attempts to quantify such interactions under tropical conditions when low anticyclonic winds become favorable to the advections from west during winters. For this purpose, a diurnal sampling was conducted using low volume sampler assembly where ambient concentrations of Nr trace gases along with their ionic fractions in the aerosol samples were determined with UV-spectrophotometer and ion chromatography respectively. The results showed a spatial gradient of the gaseous precursors with a much pronounced inter site variability (p < 0.05) than their particulate fractions. Such observations were confirmed for their limited photochemical conversions where less than 1 ratios of day and night measurements (D/N) for the different Nr fractions suggested an influence of boundary layer dynamics at the background site. These phase conversion processes were further corroborated with the molar ratios of NOₓ/NOᵧ and NH₃/NHₓ where incomplete titrations of NOₓ and NH₃ emissions were observed irrespective of their diurnal phases along the sampling transect. Their calculations with equilibrium based approaches for an NH₃-HNO₃-NH₄NO₃ system, on the other hand, were characterized by delays in equilibrium attainment where plots of their below deliquescence Kₘ and Kₚ values with 1000/T confirmed the role of lower temperature ranges in NH₄NO₃ aerosol formation. These results would help us in not only resolving the changing atmospheric inputs of reduced (NH₃, NH₄⁺) and oxidized (NOₓ, HNO₃, NO₃⁻) Nr estimates but also in understanding the dependence of Nr mixing ratios on their local meteorological conditions.Keywords: diurnal ratios, gas-aerosol interactions, spatial gradient, thermodynamic equilibrium
Procedia PDF Downloads 1272623 Advanced Nanomaterials in Catalysis: Bridging the Gap Between Pollution Control and Renewable Energy
Authors: Abonyi Matthew Ndubuisi, Christopher Chiedozie Obi, Joseph Tagbo Nwabanne
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This review focuses on the application of advanced nanomaterials in catalysis for pollution control and renewable energy solutions. This review provides a comprehensive examination of the latest developments in nanocatalysts, highlighting their role in addressing environmental challenges and facilitating sustainable energy solutions. The unique properties of nanomaterials, including high surface area, tunable electronic properties, and enhanced reactivity, make them ideal candidates for catalytic applications. This review explores various types of nanomaterials, such as metal nanoparticles, carbon-based nanostructures, and metal-organic frameworks, and their effectiveness in processes like photocatalysis, electrocatalysis, and hydrogen production. Additionally, the review discusses the environmental benefits of using nanocatalysts in pollution control, focusing on the degradation of pollutants in water and air. The potential of these materials to bridge the gap between environmental remediation and clean energy production is emphasized, showcasing their dual role in mitigating pollution and advancing renewable energy technologies. In conclusion, the review analyzes the current challenges and future directions in the field, highlighting the need for continued research to improve the design and application of nanocatalysts for a sustainable future.Keywords: nanomaterials, catalysis, pollution control, renewable energy, sustainable technology
Procedia PDF Downloads 212622 Antidiarrhea Effect of T-DABUTO from Madinella speciosa L. on Male Balb-C Mice Induced Oleum Ricini
Authors: Adhara Puspa Noorita, Azkiyatin Nailil M., Rita Aryanti, Sushanti Nuraini, Pujiati Abbas, Suparmi
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T-Dabuto is a tea made from leaves and fruits of parijoto (Madinella speciosa L.), which flavonoid, saponin and tanin contained in that tea are reported have diarrhea-caused antibacterial activity. However, the in vivo antidiarrhea effect have not clear yet. This study was conducted to determine the effect of T-DABUTO to faecal characteristics in male Balb/C-mice induced oleum ricini. Experimental research with post-test only control group design was conducted using 35 young male mice strain Balb-C which was divided into 5 groups. All groups were induced by 0.7 ml/ head of oleum ricini and 3 hours later followed by aquadest for first group, while the 2nd, 3rd, 4th and 5th group were treated by T-DABUTO solution with 75 mg/kgBW, 150 mg/kgBW, 300 mg/kgBW, and 600 mg/kgBW respectively as 0.7 ml/ head/ 0.5 hous for 8 hours. Feces collected were used to identify the frequency, absorbtion diameter and fecal weight. T-DABUTO on dose 75 mg/kg BW has the highest antidiarrhea activity which the mean of frequency defecation, water feacal absorbsion and feacal weight were 1.71±0.95 times, 0.38±0.49 mm, 0.43±0.28 mg, respectively. The T-DABUTO treatment did not influence the body weight of diarrheal mice. The T-DABUTO is potential as one of natural diarrhea tratment, especially in children.Keywords: diarrhea, flavonid, tannin, saponin
Procedia PDF Downloads 5362621 Copper Sulphate Effect on Cyprinus Carpio Common Fish Parasites
Authors: Jawdhari Abdulhusein, Dan Mihăilescu, Cristian-Emilian Pop, Nicolai Crăciun
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Cyprinus Carpio adult specimens were captured from a single spot location from the Danube River and transported to the Laboratory of Faculty of Biology, University of Bucharest. The specimens were measured, weighed and randomly divided in five groups for later Copper Sulphate (CuSO4) exposure, as well as one control group. From the control group, 3 specimens were immediately sacrificed and microscopically inspected for parasite’s presence in the gills. During the histological inspection of the control group specimens, Ichthyophthiriusmultifiliis, Gyrodactylu ssp., MyxobolusOviforis, and Trichodinacottidarumwere abundantly identified in the gills. The exposure to a single dose of CuSO4 per group took place for 7 days under controlled conditions: water alkalinity ≈ 100 mg/L, temperature 23–24 °C, oxygenation 7.40–7.80 mg/L, and pH 6.10–6.40, the parameters were monitored on an hourly basis and adjusted when needed. After the exposure, all specimens were sacrificed, and the gill tissues were inspected. It was found that concentrations of 0.10, 0.25 and 0.30 ppm of CuSO4 did not affect the presence of parasites, as for 0.40 ppm of CuSO4 it significantly affected onlyIchthyophthiriusmultifiliisandMyxobolusOviforis, while concentration 0.50 ppm of CuSO4 (≈0.20 ppm of Cu2+) eliminated all 4 parasites species previously present in the fish gills, also, there were some histopathological changes to the gills tissue. These findings suggest that low concentrations of CuSO4 treatment for fish parasites are a safe and economical option if used correctly for a brief length of time.Keywords: copper sulphate, cyprinus carpio, parasites, danube river
Procedia PDF Downloads 1362620 Role of Fish Hepatic Aldehyde Oxidase in Oxidative In Vitro Metabolism of Phenanthridine Heterocyclic Aromatic Compound
Authors: Khaled S. Al Salhen
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Aldehyde oxidase is molybdo-flavoenzyme involved in the oxidation of hundreds of endogenous and exogenous and N-heterocyclic compounds and environmental pollutants. Uncharged N-heterocyclic aromatic compounds such phenanthridine are commonly distributed pollutants in soil, air, sediments, surface water and groundwater, and in animal and plant tissues. Phenanthridine as uncharged N-heterocyclic aromatic compound was incubated with partially purified aldehyde oxidase from rainbow trout fish liver. Reversed-phase HLPC method was used to separate the oxidation products from phenanthridine and the metabolite was identified. The 6(5H)-phenanthridinone was identified the major metabolite by partially purified aldehyde oxidase from fish liver. Kinetic constant for the oxidation reactions were determined spectrophotometrically and showed that this substrate has a good affinity (Km = 78 ± 7.6 µM) for hepatic aldehyde oxidase, coupled with a relatively high oxidation rate (0.77± 0.03 nmol/min/mg protein). In addition, the kinetic parameters of hepatic fish aldehyde oxidase towards the phenanthridine substrate indicate that in vitro biotransformation by hepatic fish aldehyde oxidase will be a significant pathway. This study confirms that partially purified aldehyde oxidase from fish liver is indeed the enzyme responsible for the in vitro production 6(5H)-phenanthridinone metabolite as it is a major metabolite by mammalian aldehyde oxidase.Keywords: aldehyde oxidase, fish, phenanthridine, specificity
Procedia PDF Downloads 3612619 Basics of SCADA Security: A Technical Approach
Authors: Michał Witas
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This paper presents a technical approach to analysis of security of SCADA systems. Main goal of the paper is to make SCADA administrators aware of risks resulting from SCADA systems usage and to familiarize with methods that can be adopt to existing or planned system, to increase overall system security level. Because SCADA based systems become a industrial standard, more attention should be paid to the security of that systems. Industrial Control Systems (ICS) like SCADA are responsible for controlling crucial aspects of wide range of industrial processes. In pair with that responsibility, goes a lot of money that can be earned or lost – this fact is main reason of increased interest of attackers. Additionally ICS are often responsible for maintaining resources strategic from the point of view of national economy, like electricity (including nuclear power plants), heating, water resources or military facilities, so they can be targets of terrorist cybernetic attacks. Without proper risk analysis and management, vulnerabilities resulting from the usage of SCADA can be easily exploited by potential attacker. Paper is based mostly on own experience in systems security, gathered during academic studies and professional work in international company. As title suggests, it will cover only basics of topic, because every of points mentioned in the document can be base for additional research and papers.Keywords: denial of service, SCADA, security policy, distributed network
Procedia PDF Downloads 3702618 An Assessment of the Temperature Change Scenarios Using RS and GIS Techniques: A Case Study of Sindh
Authors: Jan Muhammad, Saad Malik, Fadia W. Al-Azawi, Ali Imran
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In the era of climate variability, rising temperatures are the most significant aspect. In this study PRECIS model data and observed data are used for assessing the temperature change scenarios of Sindh province during the first half of present century. Observed data from various meteorological stations of Sindh are the primary source for temperature change detection. The current scenario (1961–1990) and the future one (2010-2050) are acted by the PRECIS Regional Climate Model at a spatial resolution of 25 * 25 km. Regional Climate Model (RCM) can yield reasonably suitable projections to be used for climate-scenario. The main objective of the study is to map the simulated temperature as obtained from climate model-PRECIS and their comparison with observed temperatures. The analysis is done on all the districts of Sindh in order to have a more precise picture of temperature change scenarios. According to results the temperature is likely to increases by 1.5 - 2.1°C by 2050, compared to the baseline temperature of 1961-1990. The model assesses more accurate values in northern districts of Sindh as compared to the coastal belt of Sindh. All the district of the Sindh province exhibit an increasing trend in the mean temperature scenarios and each decade seems to be warmer than the previous one. An understanding of the change in temperatures is very vital for various sectors such as weather forecasting, water, agriculture, and health, etc.Keywords: PRECIS Model, real observed data, Arc GIS, interpolation techniques
Procedia PDF Downloads 2482617 Corrosive Bacteria Attached to Carbon Steel Used in Oil and Gas Company
Authors: Hadjer Didouh, Mohammed Hadj Melliani, Izzeddine Sameut Bouhaik
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Microbiologically influenced corrosion (MIC) is a major cause of pipeline failure in the oil and gas industry, particularly affecting carbon steel, which is widely used for its cost-effectiveness and mechanical properties. This study investigates the adhesion of sulfate-reducing bacteria (SRB) and other corrosive microbial species on API 5L X52 carbon steel in crude oil and injection water environments. Experimental results showed that after 72 hours of exposure, biofilm formed extensively, leading to significant corrosion rates. Weight loss measurements indicated a corrosion rate of 0.39 mm/year, with localized pitting observed at depths reaching 120 μm. Electrochemical impedance spectroscopy (EIS) revealed a drastic decrease in charge transfer resistance, from 1200 Ω/cm² for sterile samples to 240 Ω/cm² in the presence of SRB biofilm. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses confirmed the presence of iron sulfide deposits, indicating active bacterial colonization and biofilm-induced pitting corrosion. This study highlights the severe impact of MIC on pipeline infrastructure, emphasizing the need for efficient microbial control strategies. Furthermore, the results provide a framework for the development of enhanced protective coatings and environmentally friendly biocides to mitigate the economic and environmental risks associated with MIC in oilfield operations in Algeria.Keywords: MIC, corrosion, bacteria, API 5L X52
Procedia PDF Downloads 292616 Effect of Lignocellulose-Degrading Bacteria Isolated from Termite Gut on the Nutritive Value of Wheat Straw as Ruminant Feed
Authors: Ayoub Azizi-Shotorkhoft, Tahereh Mohammadabadi, Hosein Motamedi, Morteza Chaji, Hasan Fazaeli
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This study was conducted to investigate nutritive value of wheat straw processed with termite gut symbiotic bacteria with lignocellulosic-degrading potential including Bacillus licheniformis, Ochrobactrum intermedium and Microbacterium paludicola in vitro. These bacteria were isolated by culturing termite guts contents in different culture media containing different lignin and lignocellulosic materials that had been prepared from water-extracted sawdust and wheat straw. Results showed that incubating wheat straw with all of three isolated bacteria increased (P<0.05) acid-precipitable polymeric lignin (APPL) compared to control, and highest amount of APPL observed following treatment with B. licheniformis. Highest and lowest (P<0.05) in vitro gas production and ruminal organic matter digestibility were obtained when treating wheat straw with B. licheniformis and control, respectively. However, other fermentation parameters such as b (i.e., gas production from the insoluble fermentable fractions at 144h), c (i.e., rate of gas production during incubation), ruminal dry matter digestibility, metabolizable energy, partitioning factor, pH and ammonia nitrogen concentration were similar between experimental treatments (P>0.05). It is concluded that processing wheat straw with isolated bacteria improved its nutritive value as ruminants feed.Keywords: termite gut bacteria, wheat straw, nutritive value, ruminant
Procedia PDF Downloads 3322615 An Investigation of Passivation Technology in Stainless Steel Alloy
Authors: Feng-Tsai Weng, Rick Wang, Yan-Cong Liao
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Passivation is a kind of surface treatment for material to reinforce the corrosion resistance specially the stainless alloy. Passive film, is to getting more potential compared to their status before passivation. An oxidation film can be formed on the surface of stainless steel, which has a strong corrosion resistance ability after passivation treatment. In this research, a new passivation technology is proposed for a special stainless alloy which contains a 12-14% Chromium. This method includes the A-A-A (alkaline-acid-alkaline) process basically, which was developed by Carpenter that can neutralize trapped acid. Besides, a corrosion resistant coating layer was obtained by immersing the parts in a water bath of mineral oil at high temperature. Salt spray test ASTM B368 was conducted to investigated performance of corrosion resistant of the passivated stainless steel alloy parts. Results show much better corrosion resistant that followed a coating process after A-A-A Passivation process, than only using A-A-A process. The passivation time is with more than 380 hours of salt spray test ASTM B368, which is equal to 3000 hours of Salt spray test ASTM B117. Proposed passivation method of stainless steel can be completed in about 3 hours.Keywords: passivation, alkaline-acid-alkaline, stainless steel, salt spray test
Procedia PDF Downloads 3602614 Successful Optimization of a Shallow Marginal Offshore Field and Its Applications
Authors: Kumar Satyam Das, Murali Raghunathan
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This note discusses the feasibility of field development of a challenging shallow offshore field in South East Asia and how its learnings can be applied to marginal field development across the world especially developing marginal fields in this low oil price world. The field was found to be economically challenging even during high oil prices and the project was put on hold. Shell started development study with the aim to significantly reduce cost through competitively scoping and revive stranded projects. The proposed strategy to achieve this involved Improve Per platform recovery and Reduction in CAPEX. Methodology: Based on various Benchmarking Tool such as Woodmac for similar projects in the region and economic affordability, a challenging target of 50% reduction in unit development cost (UDC) was set for the project. Technical scope was defined to the minimum as to be a wellhead platform with minimum functionality to ensure production. The evaluation of key project decisions like Well location and number, well design, Artificial lift methods and wellhead platform type under different development concept was carried out through integrated multi-discipline approach. Key elements influencing per platform recovery were Wellhead Platform (WHP) location, Well count, well reach and well productivity. Major Findings: Reservoir being shallow posed challenges in well design (dog-leg severity, casing size and the achievable step-out), choice of artificial lift and sand-control method. Integrated approach amongst relevant disciplines with challenging mind-set enabled to achieve optimized set of development decisions. This led to significant improvement in per platform recovery. It was concluded that platform recovery largely depended on the reach of the well. Choice of slim well design enabled designing of high inclination and better productivity wells. However, there is trade-off between high inclination Gas Lift (GL) wells and low inclination wells in terms of long term value, operational complexity, well reach, recovery and uptime. Well design element like casing size, well completion, artificial lift and sand control were added successively over the minimum technical scope design leading to a value and risk staircase. Logical combinations of options (slim well, GL) were competitively screened to achieve 25% reduction in well cost. Facility cost reduction was achieved through sourcing standardized Low Cost Facilities platform in combination with portfolio execution to maximizing execution efficiency; this approach is expected to reduce facilities cost by ~23% with respect to the development costs. Further cost reductions were achieved by maximizing use of existing facilities nearby; changing reliance on existing water injection wells and utilizing existing water injector (W.I.) platform for new injectors. Conclusion: The study provides a spectrum of technically feasible options. It also made clear that different drivers lead to different development concepts and the cost value trade off staircase made this very visible. Scoping of the project through competitive way has proven to be valuable for decision makers by creating a transparent view of value and associated risks/uncertainty/trade-offs for difficult choices: elements of the projects can be competitive, whilst other parts will struggle, even though contributing to significant volumes. Reduction in UDC through proper scoping of present projects and its benchmarking paves as a learning for the development of marginal fields across the world, especially in this low oil price scenario. This way of developing a field has on average a reduction of 40% of cost for the Shell projects.Keywords: benchmarking, full field development, CAPEX, feasibility
Procedia PDF Downloads 1562613 Evaluating the Challenges of Large Scale Urban Redevelopment Projects for Central Government Employee Housing in Delhi
Authors: Parul Kapoor, Dheeraj Bhardwaj
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Delhi and other Indian cities accommodate thousands of Central Government employees in housing complexes called ‘General Pool Residential Accommodation’ (GPRA), located in prime parcels of the city. These residential colonies are now undergoing redevelopment at a massive scale, significantly impacting the ecology of the surrounding areas. Essentially, these colonies were low-rise, low-density planned developments with a dense tree cover and minimal parking requirements. But with increasing urbanisation and spike in parking demand, the proposed built form is an aggregate of high-rise gated complexes, redefining the skyline of the city which is a huge departure from the mediocre setup of Low-rise Walk-up apartments. The complexity of these developments is further aggravated by the need for parking which necessitates cutting huge number of trees to accommodate multiple layers of parking beneath the structures thus sidelining the authentic character of these areas which is laden with a dense tree cover. The aftermath of this whole process is the generation of a huge carbon footprint on the surrounding areas, which is unaccounted for, in the planning and design practice. These developments are currently planned as mix-use compounds with large commercial built-up spaces which have additional parking requirements over and above the residential parking. Also, they are perceived as gated complexes and not as neighborhood units, thus project isolated images of high-rise, dense systems with little context to the surroundings. The paper would analyze case studies of GPRA Redevelopment projects in Delhi, and the lack of relevant development control regulations which have led to abnormalities and complications in the entire redevelopment process. It would also suggest policy guidelines which can establish comprehensive codes for effective planning of these settlements.Keywords: gated complexes, GPRA Redevelopment projects, increased densities, huge carbon footprint, mixed-use development
Procedia PDF Downloads 1242612 Knowledge of Risk Factors and Health Implications of Fast Food Consumption among Undergraduate in Nigerian Polytechnic
Authors: Adebusoye Michael, Anthony Gloria, Fasan Temitope, Jacob Anayo
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Background: The culture of fast food consumption has gradually become a common lifestyle in Nigeria especially among young people in urban areas, in spite of the associated adverse health consequences. The adolescent pattern of fast foods consumption and their perception of this practice, as a risk factor for Non-Communicable Diseases (NCDs), have not been fully explored. This study was designed to assess fast food consumption pattern and the perception of it as a risk factor for NCDs among undergraduates of Federal Polytechnic, Bauchi. Methodology: The study was descriptive cross-sectional in design. One hundred and eighty-five students were recruited using systematic random sampling method from the two halls of residence. A structured questionnaire was used to assess the consumption pattern of fast foods. Data collected from the questionnaires were analysed using statistical package for the social sciences (SPSS) version 16. Simple descriptive statistics, such as frequency counts and percentages were used to interpret the data. Results: The age range of respondents was 18-34 years, 58.4% were males, 93.5% singles and 51.4% of their parents were employed. The majority (100%) were aware of fast foods and (75%) agreed to its implications as NCD. Fast foods consumption distribution included meat pie (4.9%), beef roll/ sausage (2.7%), egg roll (13.5%), doughnut (16.2%), noodles(18%) and carbonated drinks (3.8%). 30.3% consumed thrice in a week and 71% attached workload to high consumption of fast food. Conclusion: It was revealed that a higher social pressure from peers, time constraints, class pressure and school programme had the strong influence on high percentages of higher institutions’ students consume fast foods and therefore nutrition educational campaigns for campus food outlets or vendors and behavioural change communication on healthy nutrition and lifestyles among young people are hereby advocated.Keywords: fast food consumption, Nigerian polytechnic, risk factors, undergraduate
Procedia PDF Downloads 4692611 Cold Stunned Sea Turtle Diet Analysis In Cape Cod Bay from 2015-2020
Authors: Lucille McWilliams
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As water temperatures drop in November, Kemp’s Ridley, Loggerhead, and Green sea turtles cold-stun in Cape Cod Bay. The foraging ecology of these sea turtles remains an understudied area of research. In this study, we aim to assess the diet of these turtles using a multi-tissue stable isotope analysis of cold-stunned kemp’s ridley, loggerhead, and green sea turtles stranded from 2015 to 2020. Stable isotope ratios of carbon and nitrogen were measured in blood, front and rear flipper, liver, muscle, skin, and scute tissue samples. We predict an elevated level of Nitrogen isotope ratios in kemp’s ridley and loggerhead turtles compared to green turtles due to the carnivorous loggerheads and kemp ridleys’ carnivorous diet and the greens herbivorous diet. We anticipate empty stomachs due to starvation while stranded, and a variety of foraging strategies, migration patterns, and trophic positions between these species. Data collected from this study will add to the knowledge of these turtles’ prey species and aid managers in the preservation of these species as a mitigation strategy for these turtles' extinction.Keywords: sea turtles, kemp's ridleys, greens, loggerheads, cold-stunning, diet analysis, stable isotope analysis, environmental science, marine biology
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