Search results for: nitrogen accumulation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1918

Search results for: nitrogen accumulation

808 Membrane Bioreactor versus Activated Sludge Process for Aerobic Wastewater Treatment and Recycling

Authors: Sarra Kitanou

Abstract:

Membrane bioreactor (MBR) systems are one of the most widely used wastewater treatment processes for various municipal and industrial waste streams. It is based on complex interactions between biological processes, filtration process and rheological properties of the liquid to be treated. Its complexity makes understanding system operation and optimization more difficult, and traditional methods based on experimental analysis are costly and time consuming. The present study was based on an external membrane bioreactor pilot scale with ceramic membranes compared to conventional activated sludge process (ASP) plant. Both systems received their influent from a domestic wastewater. The membrane bioreactor (MBR) produced an effluent with much better quality than ASP in terms of total suspended solids (TSS), organic matter such as biological oxygen demand (BOD) and chemical oxygen demand (COD), total Phosphorus and total Nitrogen. Other effluent quality parameters also indicate substantial differences between ASP and MBR. This study leads to conclude that in the case domestic wastewater, MBR treatment has excellent effluent quality. Hence, the replacement of the ASP by the MBRs may be justified on the basis of their improved removal of solids, nutrients, and micropollutants. Furthermore, in terms of reuse the great quality of the treated water allows it to be reused for irrigation.

Keywords: aerobic wastewater treatment, conventional activated sludge process, membrane bioreactor, reuse for irrigation

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807 An Electrode Material for Ultracapacitors: Hydrothermal Synthesis of Neodymium Oxide/Manganese Oxide/Nitrogen Doped Reduced Graphene Oxide Ternary Nanocomposites

Authors: K. Saravanan, K. A.Rameshkumar, P. Maadeswaran

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The depletion of fossil resources and the rise in global temperatures are two of the most important concerns we confront today. There are numerous renewable energy sources like solar power, tidal power, wind energy, radiant energy, hydroelectricity, geothermal energy, and biomass available to generate the needed energy demand. Engineers and scientists around the world are facing a massive barrier in the development of storage technologies for the energy developed from renewable energy sources. The development of electrochemical capacitors as a future energy storage technology is at the forefront of current research and development. This is due to the fact that the electrochemical capacitors have a significantly higher energy density, a faster charging-discharging rate, and a longer life span than capacitors, and they also have a higher power density than batteries, making them superior to both. In this research, electrochemical capacitors using the Nd2O3/Mn3O4/ N-rGO electrode material is chosen since the of hexagonal and tetragonal crystal structures of Nd2O3 and Mn3O4 and also has cycling stability of 68% over a long time at 50mVs-1 and a high coulombic efficiency of 99.64% at 5 Ag-1. This approach may also be used to create novel electrode materials with improved electrochemical and cyclic stability for high-performance supercapacitors.

Keywords: Nd2O3/Mn3O4/N-rGO, nanocomposites, hydrothermal method, electrode material, specific capacitance, use of supercapacitors

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806 Examining the Role of Soil pH on the Composition and Abundance of Nitrite Oxidising Bacteria

Authors: Mansur Abdulrasheed, Hussein I. Ibrahim, Ahmed F. Umar

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Nitrification, the microbial oxidation of ammonia to nitrate (NO3-) via nitrite (NO2-) is a vital process in the biogeochemical nitrogen cycle and is performed by two distinct functional groups; ammonia oxidisers (comprised of ammonia oxidising bacteria (AOB) and ammonia oxidising archaea (AOA)) and nitrite oxidising bacteria. Autotrophic nitrification is said to occur in acidic soils, even though most laboratory cultures of isolated ammonia and nitrite oxidising bacteria fail to grow below neutral pH. Published studies revealed that soil pH is a major driver for determining the distribution and abundance of AOB and AOA. To determine whether distinct populations of nitrite oxidising bacteria within the lineages of Nitrospira and Nitrobacter are adapted to a particular range of pH as observed in ammonia oxidising organisms, the community structure of Nitrospira-like and Nitrobacter-like NOB were examined across a pH gradient (4.5–7.5) by amplifying nitrite oxido-reductase (nxrA) and 16S rRNA genes followed by denaturing gradient gel electrophoresis (DGGE). The community structure of both Nitrospira and Nitrobacter changed with soil pH, with distinct populations observed in acidic and neutral soils. The abundance of Nitrospira-like 16S rRNA and Nitrobacter-like nxrA gene copies contrasted across the pH gradient. Nitrobacter-like nxrA gene abundance decreased with increasing soil pH, whereas Nitrospira-like 16S rRNA gene abundance increased with increasing pH. Findings indicated that abundance and distributions of soil NOB is influence by soil pH.

Keywords: nitrospira, nitrobacter, nitrite-oxidizing bacteria, nitrification, pH, soil

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805 Analysis of Veterinary Drug Residues and Pesticide Residues in Beehive Products

Authors: Alba Luna Jimenez, Maria Dolores Hernando

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The administration of veterinary treatments at higher doses than the recommended Varroa mite control in beehive matrices has the potential to generate residues in the honeybee colony and in the derived products for consumption. Honeybee colonies can also be indirectly exposed to residues of plant protection products when foraging in crops, wildflowers near the crops, or in urban gardens just after spraying. The study evaluates the presence of both types of residues, veterinary treatments, and pesticides in beeswax, bee bread, and honey. The study was carried out in apiaries located in agricultural zones and forest areas in Andalusia, Spain. Up to nineteen residues were identified above LOQ using gas chromatography-triple quadrupole-mass spectrometry analysis (GC-MS/MS). Samples were extracted by a modified QuEChERs method. Chlorfenvinphos was detected in beeswax and bee bread despite its use is not authorized for Varroa mite control. Residues of fluvalinate-tau, authorized as veterinary treatment, were detected in most of the samples of beeswax and bee bread, presumably due to overdose or also to its potential for accumulation associated with its marked liposolubility. Residues of plant protection products were also detected in samples of beeswax and bee bread. Pesticide residues were detected above the LOQ that was established at 5 µg.kg⁻¹, which is the minimum concentration that can be quantified with acceptable accuracy and precision, as described in the European guidelines for pesticide residue analysis SANTE/11945/2015. No residues of phytosanitary treatments used in agriculture were detected in honey.

Keywords: honeybee colony, mass spectrometry analysis, pesticide residues, Varroa destructor, veterinary treatment

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804 The Reduction of Post-Blast Fumes to Improve Productivity and Safety: A Review Paper

Authors: Nhleko Monique Chiloane

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The gold mining industry has predominantly used ammonium nitrate fuel oil (ANFO) explosives for decades, although these are known to be “gassier” and their detonation results in toxic fumes, for example, carbon monoxide (CO), nitrogen oxides (NOx) and ammonia. Re-entry into underground workings too soon after blasting can lead to fatal exposure to toxic fumes. It is, therefore, required that the polluted air be removed from the affected areas within a reasonable period before employees' re-entry into the working area. Post-blast re-entry times have therefore been described as a productivity bottleneck. The known causes of post-blast fumes are water ingress, incorrect fuel to oxygen ratio, confinement, explosive additives etc. To prevent or minimize post-blast fumes, some researchers have used neutralization, re-burning technique and non-explosive products or different oxidizing agents. The use of commercial explosives without nitrate oxidizing agents can also minimize the production of blasting fumes and thereby reduce the time needed for the clearance of these fumes to allow workers to re-enter the underground workings safely. The reduction in non-production time directly contributes to an increase in the available time per shift for productive work, thus leading to continuous mining. However, owing to its low cost and ease of use, ANFO is still widely used in South African underground blasting operations.

Keywords: post-blast fumes, continuous mining, ammonium nitrate explosive, non-explosive blasting, re-entry period

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803 Experimental Investigation of the Effect of Compression Ratio in a Direct Injection Diesel Engine Running on Different Blends of Rice Bran Oil and Ethanol

Authors: Perminderjit Singh, Randeep Singh

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The performance, emission and combustion characteristics of a single cylinder four stroke variable compression ratio multifuel engine when fueled with different blends of rice bran oil methyl ester and ethanol are investigated and compared with the results of standard diesel. Biodiesel produced from rice bran oil by transesterification process has been used in this study. The experiment has been conducted at a fixed engine speed of 1500 rpm, 50% load and at compression ratios of 16.5:1, 17:1, 17.5:1 and 18:1. The impact of compression ratio on fuel consumption, brake thermal efficiency and exhaust gas emissions has been investigated and presented. Optimum compression ratio which gives the best performance has been identified. The results indicate longer ignition delay, the maximum rate of pressure rise, lower heat release rate and higher mass fraction burnt at higher compression ratio for waste cooking oil methyl ester when compared to that of diesel. The brake thermal efficiency at 50% load for rice bran oil methyl ester blends and diesel has been calculated and the blend B40 is found to give maximum thermal efficiency. The blends when used as fuel results in the reduction of carbon monoxide, hydrocarbon and increase in nitrogen oxides emissions.

Keywords: biodiesel, rice bran oil, transesterification, ethanol, compression ratio

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802 Anthocyanins as Markers of Enhanced Plant Defence in Maize (Zea Mays L.) Exposed to Copper Stress

Authors: Fadime Eryılmaz Pehlivan

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Anthocyanins are important plant pigments having roles in many physiological and ecological functions; that are controlled by numerous regulatory factors. The accumulation of anthocyanins in Z. mays cause the plants stems to exhibit red coloration when encountering gradually increasing copper treatments (1, 5, and 10 mM of Cu in a period of 5 days) on maize seedlings. Stress injury was measured in terms of chlorophyll (a and b), carotenoid and anthocyanin contents, malondialdehyde (MDA), hydrogen peroxide (H2O2). Carotenoid and anthocyanin contents dramatically increased by increasing concentrations of Cu stress. MDA and H2O2 levels were found to significantly increase at high Cu treatments (5 and 10 mM of Cu). Chlorophyll content was observed to be highest at 1 mM Cu and then decreased at 5 and 10 mM of Cu. In addition, significant increases were determined in the activities of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and ascorbate peroxidase (APX) under high Cu concentrations, while glutathione S-transferase (GST) and peroxidase (POX) activities showed no change. Treatments above 5 and 10 mM of Cu triggered copper stress in maize seedlings. The results of this study provide evidence that maize seedlings represent a high tolerance to gradually increasing copper treatments. Improved copper tolerance may relate to high anthocyanin, and carotenoid content besides antioxidant enzyme activity may improve the metal chelating ability of anthocyanin pigments. Data presented in this study may also contribute to a better understanding of phytoremediation studies in maize exposed to high copper contenting soils.

Keywords: anthocyanin, copper, maize , antioxidant

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801 Investigation into the Homoepitaxy of AlGaN/GaN Heterostructure via Molecular Beam Epitaxy

Authors: Jiajia Yao, Guanlin Wu, Fang Liu, Junshuai Xue, Yue Hao

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As the production process of self-standing GaN substrates evolves, the commercialization of low dislocation density, large-scale, semi-insulating self-standing GaN substrates is gradually becoming a reality. This advancement has given rise to increased interest in GaN materials' homoepitaxial technology. However, at the homoepitaxial interface, there are considerable concentrations of impurity elements, including C, Si, and O, which generate parasitic leakage channels at the re-growth junction. This phenomenon results in leaked HEMTs that prove difficult to switch off, rendering them effectively non-functional. The emergence of leakage channels can also degrade the high-frequency properties and lower the power devices' breakdown voltage. In this study, the uniform epitaxy of AlGaN/GaN heterojunction with high electron mobility was accomplished through the surface treatment of the GaN substrates prior to growth and the design of the AlN isolation layer structure. By employing a procedure combining gallium atom in-situ cleaning and plasma nitridation, the C and O impurity concentrations at the homoepitaxial interface were diminished to the scale of 10¹⁷ cm-³. Additionally, the 1.5 nm nitrogen-rich AlN isolation layer successfully prevented the diffusion of Si impurities into the GaN channel layer. The result was an AlGaN/GaN heterojunction with an electron mobility of 1552 cm²/Vs and an electron density of 1.1 × 10¹³ cm-² at room temperature, obtained on a Fe-doped semi-insulating GaN substrate.

Keywords: MBE, AlGaN/GaN, homogenerous epitaxy, HEMT

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800 Determination of Marbofloxacin in Pig Plasma Using LC-MS/MS and Its Application to the Pharmacokinetic Studies

Authors: Jeong Woo Kang, MiYoung Baek, Ki-Suk Kim, Kwang-Jick Lee, ByungJae So

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Introduction: A fast, easy and sensitive detection method was developed and validated by liquid chromatography tandem mass spectrometry for the determination of marbofloxacin in pig plasma which was further applied to study the pharmacokinetics of marbofloxacin. Materials and Methods: The plasma sample (500 μL) was mixed with 1.5 ml of 0.1% formic acid in MeCN to precipitate plasma proteins. After shaking for 20 min, The mixture was centrifuged at 5,000 × g for 30 min. It was dried under a nitrogen flow at 50℃. 500 μL aliquot of the sample was injected into the LC-MS/MS system. Chromatographic analysis was carried out mobile phase gradient consisting 0.1% formic acid in D.W. (A) and 0.1% formic acid in MeCN (B) with C18 reverse phase column. Mass spectrometry was performed using the positive ion mode and the selected ion monitoring (MRM). Results and Conclusions: The method validation was performed in the sample matrix. Good linearities (R2>0.999) were observed and the quantified average recoveries of marbofloxacin were 87 - 92% at level of 10 ng g-1 -100 ng g-1. The percent of coefficient of variation (CV) for the described method was less than 10 % over the range of concentrations studied. The limits of detection (LOD) and quantification (LOQ) were 2 and 5 ng g-1, respectively. This method has also been applied successfully to pharmacokinetic analysis of marbofloxacin after intravenous (IV), intramuscular (IM) and oral administration (PO). The mean peak plasma concentration (Cmax) was 2,597 ng g-1at 0.25 h, 2,587 ng g-1at 0.44 h and 2,355 ng g-1at 1.58 h for IV, IM and PO, respectively. The area under the plasma concentration-time curve (AUC0–t) was 24.8, 29.0 and 25.2 h μg/mL for IV, IM and PO, respectively. The elimination half-life (T1/2) was 8.6, 13.1 and 9.5 for IV, IM and PO, respectively. Bioavailability (F) of the marbofloxacin in pig was 117 and 101 % for IM and PO, respectively. Based on these result, marbofloxacin does not have any obstacles as therapeutics to develop the oral formulations such as tablets and capsules.

Keywords: marbofloxacin, LC-MS/MS, pharmacokinetics, chromatographic

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799 An Introduction to the Current Epistemology of Ethical Philosophy of Islamic Banking

Authors: Mohd Iqbal Malik

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Ethical philosophy of Quran pinnacled virtue and economics as the part and parcel of human life. Human beings are to be imagined by the sign of morals. Soul and morality are both among the essences of human personality. Islam lays the foundation of ethics by installation of making a momentous variance between virtue and vice. It suggests for the distribution of wealth in-order to terminate accumulation of economic resources. Quran claims for the ambiguous pavement to attain virtue by saying, ‘Never will you attain the good (reward) until you spend (in the way of Allah) from that which you love. And whatever you spend indeed, Allah knows of it.’ The essence of Quran is to eliminate all the deep-seated approaches through which the wealth of nations is being accumulated within few hands. The paper will study the Quranic Philosophy Of Islamic Economic System. In recent times, to get out of the human resource development mystery of Muslims, Ismail Al-Raji Faruqi led the way in the so-called ‘Islamization’ of knowledge. Rahman and Faruqi formed opposite opinions on this project. Al-Faruqi thought of the Islamization of knowledge in terms of introducing Western learning into received Islamic values and vice versa. This proved to be a mere peripheral treatment of Islamic values in relation to Western knowledge. It is true that out of the programme of Islamization of knowledge arose Islamic universities in many Muslim countries. Yet the academic programmes of these universities were not founded upon a substantive understanding and application of the tawhidi epistemology.

Keywords: ethical philosophy, modern Islamic finance, knowledge of finance, Islamic banking

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798 Evaluation of Different Fertilization Practices and Their Impacts on Soil Chemical and Microbial Properties in Two Agroecological Zones of Ghana

Authors: Ansong Richard Omari, Yosei Oikawa, Yoshiharu Fujii, Dorothea Sonoko Bellingrath-Kimura

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Renewed interest in soil management aimed at improving the productive capacity of Sub Saharan Africa (SSA) soils has called for the need to analyse the long term effect of different fertilization systems on soil. This study was conducted in two agroecological zones (i.e., Guinea Savannah (GS) and Deciduous forest (DF)) of Ghana to evaluate the impacts of long term (> 5 years) fertilization schemes on soil chemical and microbial properties. Soil samples under four different fertilization schemes (inorganic, inorganic and organic, organic, and no fertilization) were collected from 20 farmers` field in both agroecological zones. Soil analyses were conducted using standard procedures. All average soil quality parameters except extractable C, potential mineralizable nitrogen and CEC were significantly higher in DF sites compared to GS. Inorganic fertilization proved superior in soil chemical and microbial biomass especially in GS zone. In GS, soil deterioration index (DI) revealed that soil quality deteriorated significantly (−26%) under only organic fertilization system whereas soil improvement was observed under inorganic and no fertilization sites. In DF, either inorganic or organic and inorganic fertilization showed significant positive effects on soil quality. The high soil chemical composition and enhanced microbial biomass in DF were associated with the high rate of inorganic fertilization.

Keywords: deterioration index, fertilization scheme, microbial biomass, tropical agroecological zone

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797 Physicochemical Characterization of Waste from Vegetal Extracts Industry for Use as Briquettes

Authors: Maíra O. Palm, Cintia Marangoni, Ozair Souza, Noeli Sellin

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Wastes from a vegetal extracts industry (cocoa, oak, Guarana and mate) were characterized by particle size, proximate and ultimate analysis, lignocellulosic fractions, high heating value, thermal analysis (Thermogravimetric analysis – TGA, and Differential thermal analysis - DTA) and energy density to evaluate their potential as biomass in the form of briquettes for power generation. All wastes presented adequate particle sizes to briquettes production. The wastes showed high moisture content, requiring previous drying for use as briquettes. Cocoa and oak wastes had the highest volatile matter contents with maximum mass loss at 310 ºC and 450 ºC, respectively. The solvents used in the aroma extraction process influenced in the moisture content of the wastes, which was higher for mate due to water has been used as solvent. All wastes showed an insignificant loss mass after 565 °C, hence resulting in low ash content. High carbon and hydrogen contents and low sulfur and nitrogen contents were observed ensuring a low generation of sulfur and nitrous oxides. Mate and cocoa exhibited the highest carbon and lignin content, and high heating value. The dried wastes had high heating value, from 17.1 MJ/kg to 20.8 MJ/kg. The results indicate the energy potential of wastes for use as fuel in power generation.

Keywords: agro-industrial waste, biomass, briquettes, combustion

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796 Bioremoval of Malachite Green Dye from Aqueous Solution Using Marine Algae: Isotherm, Kinetic and Mechanistic Study

Authors: M. Jerold, V. Sivasubramanian

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This study reports the removal of Malachite Green (MG) from simulated wastewater by using marine macro algae Ulva lactuca. Batch biosorption experiments were carried out to determine the biosorption capacity. The biosorption capacity was found to be maximum at pH 10. The effect of various other operation parameters such as biosorbent dosage, initial dye concentration, contact time and agitation was also investigated. The equilibrium attained at 120 min with 0.1 g/L of biosorbent. The isotherm experimental data fitted well with Langmuir Model with R² value of 0.994. The maximum Langmuir biosorption capacity was found to be 76.92 mg/g. Further, Langmuir separation factor RL value was found to be 0.004. Therefore, the adsorption is favorable. The biosorption kinetics of MG was found to follow pseudo second-order kinetic model. The mechanistic study revealed that the biosorption of malachite onto Ulva lactuca was controlled by film diffusion. The solute transfer in a solid-liquid adsorption process is characterized by the film diffusion and/or particle diffusion. Thermodynamic study shows ΔG° is negative indicates the feasibility and spontaneous nature for the biosorption of malachite green. The biosorbent was characterized using Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, and elemental analysis (CHNS: Carbon, Hydrogen, Nitrogen, Sulphur). This study showed that Ulva lactuca can be used as promising biosorbent for the removal of MG from wastewater.

Keywords: biosorption, Ulva lactuca, wastewater, malachite green, isotherm, kinetics

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795 Effect of Biochar, Farmyard Manure, and Lime on Soil Properties, and on Growth and Nutrient Uptake of Wheat on Acidic Soils in Southern Ethiopia

Authors: Mekdes Lulu

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This study assessed the effect of the interactions of biochar (BC), farmyard manure (FYM) and lime on soil chemical properties and on different wheat attributes in Southern Ethiopia. The experimental design was a randomized complete block in three replications. The site significantly (p ≤ 0.05) influenced soil and wheat attributes. Biochar showed a large significant effect (p ≤ 0.05) on soil organic carbon, cation exchange capacity, and exchangeable potassium (K), while lime showed a substantially significant (p ≤ 0.05) effect on exchangeable Calcium (Ca) and acidity. Farmyard manure (10 tonnes ha−1 ) had a significant effect on soil total nitrogen (TN). Biochar and lime showed a large significant effect on soil pH and available phosphorus (P) depending on the site. All amendments showed a significant (p ≤ 0.001) effect on most wheat attributes, but the highest effect was from BC. Biochar produced highly significant (p ≤ 0.001) effects on plant height, total number of tillers and productive tillers, number of seeds per spike, aboveground biomass, grain yield, and P and K content in wheat grain and straw. We accredited the greater effect of BC on wheat attributes to its influence on soil chemical properties. We recommend long-term studies on the impact of BC alone or in combination with FYM on acid soil types.

Keywords: grain yield, soil amendments, soil nutrients, soil organic carbon, Triticum aestivum

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794 African Mesquite Exerts Neuroprotective Activity Against Quaternary Metal Mixture -Induced Olfactory Bulb-Hippocampal Oxido-Inflammatory Stress via NRF2-HMOX-1-TNF-Alpha Pathway Pathway

Authors: Orish E. Orisakwe, Chinna N. Orish, Anthonet N. Ezejiofor

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African mesquite has been recognized for its antimicrobial, anti-inflammatory, and potential anticarcinogenic activities. However, its neuroprotective benefits against heavy metal-induced neurotoxicity remain largely unexplored. Therefore, the objective of this study was to investigate the neuroprotective properties of African mesquite in the hippocampus and olfactory bulb against common environmental pollutants, including Cd, As, Hg, and Pb. Thirty-five albino Sprague Dawley rats were divided into five groups for the experiment. Group 1 served as the control and did not receive either the heavy metal mixture (HMM) or African mesquite. Group 2 was orally administered HMM, consisting of PbCl2 (20 mg/kg), CdCl2 (1.61 mg/kg), HgCl2 (0.40 mg/kg), and NaAsO3 (10 mg/kg), for 960 days. Meanwhile, groups 3, 4, and 5 were treated with HMM along with African mesquite at doses of 500 mg/kg, 1000 mg/kg, and 1500 mg/kg, respectively. African mesquite reduced heavy metal accumulation in the hippocampus and olfactory bulb. Additionally, Sprague Dawley rats exhibited improved performance in the Passive avoidance and Cincinnati Maze tests. Furthermore, treatment with African mesquite significantly alleviated inflammation macromolecules peroxidation. It also restored the concentrations of SOD, CAT, GSH, GPx, Hmox-1, and reduced the activity of AChE, NRF2 and NFkB and improved histopathological findings. African mesquite exhibits a multifaceted neuroprotective effect with the potential to mitigate various aspects of heavy metal-induced neurotoxicity.

Keywords: African mesquite, heavy metal mixture;, neurotoxicity;, chemoprevention

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793 Effect of Tillage Techniques on the Performance of Kharif Rice Varieties

Authors: Mahua Banerjee, Debtanu Maiti

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Zero-tillage cultivation is a farming practice that reduces costs while maintaining harvests and protecting the environment. Innovative partnerships among researchers, farmers, and other actors in the agricultural value chain have enabled the adoption of zero-tillage to sow rice in the Indo-Gangetic Plains, increasing farmers' incomes, fostering more sustainable use of soil and water, and providing a platform for cropping diversification and the introduction of other resource-conserving practices. A field experiment was conducted in the farmer’s field of Ausgram I Block, Burdwan, West Bengal, India under sandy loam soil with soil pH of 5.2, which is low in Nitrogen, medium in Phosphorus and Potassium. There were three techniques of tillage-T1: Zero tillage in Rice, T2: conventional tillage in Rice, T3: Rice grown with Drum seeder and three varieties namely V1: MTU 7029 V2-MTU 1010, V3: Pratikha thus making nine treatment combinations which were replicated thrice and the experiment was laid out in Factorial Randomised Block Design. Among the three varieties, rice variety MTU 7029 gave higher yield in all the tillage techniques. The highest yield was obtained under Zero tillage followed by conventional tillage. From economic analysis it was revealed that the benefit:cost ratio was higher in Zero tillage and rice cultivation by drum seeder. Zero-till is increasingly being adopted because it gives more yield at less cost, saves labour and farmer time. Farmers will be interested in this technology once they overcome their tillage biases.

Keywords: economics, Indo-Gangetic plain, rice, zero tillage, yield

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792 Effect of Lactic Acid Bacteria Inoculant on Fermentation Quality of Sweet Sorghum Silage

Authors: Azizza Mala, Babo Fadlalla, Elnour Mohamed, Siran Wang, Junfeng Li, Tao Shao

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Sweet sorghum is considered one of the best plants for silage production and is now a more important feed crop in many countries worldwide. It is simple to ensile because of its high water-soluble carbohydrates (WSC) concentration and low buffer capacity. This study investigated the effect of adding Pediococcus acidilactici AZZ5 and Lactobacillus plantarum AZZ4 isolated from elephant grass on the fermentation quality of sweet sorghum silage. One commercial bacteria Lactobacillus Plantarum, Ecosyl MTD/1(C.B.)), and two strains were used as additives Pediococcus acidilactici (AZZ5), Lactobacillus plantarum subsp. Plantarum (AZZ4) at 6 log colony forming units (cfu)/g of fresh sweet sorghum grass in laboratory silos (1000g). After 15, 30, and 60 days, the silos for each treatment were opened. All of the isolated strains enhanced the silage quality of sweet sorghum silage compared to the control, as evidenced by significantly (P < 0.05) lower ammonia nitrogen (NH3-N) content and undesirable microbial counts, as well as greater lactic acid (L.A.) contents and lactic acid/acetic acid (LA/AA) ratios. In addition, AZZ4 performed better than all other inoculants during ensiling, as evidenced by a significant (P < 0.05) reduction in pH and ammonia-N contents and a significant increase in lactic acid contents.

Keywords: fermentation, lactobacillus plantarum, lactic acid bacteria, pediococcus acidilactic, sweet sorghum

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791 Waterless Fracking: An Alternative to Conventional Fracking

Authors: Shubham Damke, Md Imtiaz, Sanchita Dei

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To stimulate the well and to enhance the production from the shaly formations, fracturing is essential. Presently the chiefly employed technology is Hydraulic Fracturing. However Hydraulic Fracturing accompanies itself with problems like disposing large volumes of fracturing wastewater, removal of water from the pores, formation damage due to injection of large amount of chemicals into underground formations and many more. Therefore embarking on the path of innovation new techniques have been developed which uses different gases such as Nitrogen, Carbon dioxide, Frac Oil, LPG, etc. are used as a base fluid for fracturing formation. However LPG proves to be the most favorable of them which eliminates the use of water and chemicals. When using it as a fracturing fluid, within the surface equipment, it is stored, gelled, and proppant blended at a constant pressure. It is then pressurized with high pressure pumps to the required surface injection pressure With lowering the total cost and increasing the productivity, LPG is also very noteworthy for fracturing shale, where if the hydraulic fracturing is done the water ‘swells’ the formation and creates surface tension, both of which inhibit the flow of oil and gas. Also fracturing with LPG increases the effective fracture length and since propane, butane and pentane is used which are already present in the natural gas therefore there is no problem of back flow because these gases get mixed with the natural gas. LPG Fracturing technology can be a promising substitute of the Hydraulic Fracturing, which could substantially reduce the capital cost of fracturing shale and will also restrict the problems with the disposal of water and on the same hand increasing the fracture length and the productivity from the shale.

Keywords: Fracking, Shale, Surface Tension, Viscosity

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790 Potential Impact of Sodium Salicylate Nanoemulsion on Expression of Nephrin in Nephrotoxic Experimental Rat

Authors: Nadia A. Mohamed, Zakaria El-Khayat, Wagdy K. B. Khalil, Mehrez E. El-Naggar

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Drug nephrotoxicity is still a problem for patients who have taken drugs for elongated periods or permanently. Ultrasound-assisted sol−gel method was used to prepare hollow structured poroussilica nanoemulsion loaded with sodium salicylate as a model drug. The work was extended to achieve the target of the current work via investigating the protective role of this nanoemulsion model as anti-inflammatory drug or ginger for its antioxidant effect against cisplatin-induced nephrotoxicity in male albino rats. The results clarify that the nanoemulsion model was synthesized using ultrasonic assisted with small size and well stabilization as proved by TEM and DLS analysis. Additionally, blood urea nitrogen (BUN), Serum creatinine (SC) and Urinary total protein (UTP) were increased, and the level of creatinine clearance (Crcl) was decreased. All those were met with disorders in oxidative stress and downregulation in the expression of the nephrin gene. Also, histopathological changes of the kidney tissue were observed. These changes back to normal by treatment with silica nanoparticles loaded sodium salicylate (Si-Sc-NPs), ginger or both. Conclusions oil/water nanoemulsion of (Si-Sc NPs) and ginger showed a protective and promising preventive strategy against nephrotoxicity due to their antioxidant and anti-inflammatory effects, and that offers a new approach in attenuating drug induced nephrotoxicity.

Keywords: sodium salicylate nanoencapsulation, nephrin mRNA, drug nephrotoxicity, cisplatin, experimental rats

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789 Analysis of Possible Equipment in the Reduction Unit of a Low Tonnage Liquefied Natural Gas Production Plant

Authors: Pavel E. Mikriukov

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The demand for natural gas (NG) is increasing every year around the world, so it is necessary to produce and transport NG in large quantities. To solve this problem, liquefied natural gas (LNG) plants are used, using different equipment and different technologies to achieve the required LNG quality. To determine the best efficiency of the LNG liquefaction plant, it is necessary to analyze the equipment used in this process and identify other technological solutions for LNG production using more productive and energy-efficient equipment. Based on this, mathematical models of the technological process of the LNG plant were created, which are based on a two-circuit system of heat exchange equipment and a nitrogen isolated cycle for NG cooling. The final liquefaction of natural gas is performed on the construction of the basic principle of the Joule-Thompson effect. The pressure and temperature drop are considered on different types of equipment such as throttle valve, which was used in the basic scheme; turbo expander and supersonic separator, which act as new equipment, to be compared with the efficiency of the basic scheme of the unit. New configurations of LNG plants are suggested, which can be used in almost all LNG facilities. As a result of the analysis, it turned out that the turbo expander and the supersonic separator have comparatively equal potential in comparison with the baseline scheme execution on the throttle valve. A more rational method of selecting the technology and the equipment used for natural gas liquefaction can improve the efficiency of low-tonnage plants and reduce the cost of gas for own needs.

Keywords: gas liquefaction, gas, Joule-Thompson effect, LNG, low-tonnage LNG, supersonic separator, Throttle valve, turbo expander

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788 Experimental Investigation, Analysis and Optimization of Performance and Emission Characteristics of Composite Oil Methyl Esters at 160 bar, 180 bar and 200 bar Injection Pressures by Multifunctional Criteria Technique

Authors: Yogish Huchaiah, Chandrashekara Krishnappa

Abstract:

This study considers the optimization and validation of experimental results using Multi-Functional Criteria Technique (MFCT). MFCT is concerned with structuring and solving decision and planning problems involving multiple variables. Production of biodiesel from Composite Oil Methyl Esters (COME) of Jatropha and Pongamia oils, mixed in various proportions and Biodiesel thus obtained from two step transesterification process were tested for various Physico-Chemical properties and it has been ascertained that they were within limits proposed by ASTME. They were blended with Petrodiesel in various proportions. These Methyl Esters were blended with Petrodiesel in various proportions and coded. These blends were used as fuels in a computerized CI DI engine to investigate Performance and Emission characteristics. From the analysis of results, it was found that 180MEM4B20 blend had the maximum Performance and minimum Emissions. To validate the experimental results, MFCT was used. Characteristics such as Fuel Consumption (FC), Brake Power (BP), Brake Specific Fuel Consumption (BSFC), Brake Thermal Efficiency (BTE), Carbon dioxide (CO2), Carbon Monoxide (CO), Hydro Carbon (HC) and Nitrogen oxide (NOx) were considered as dependent variables. It was found from the application of this method that the optimized combination of Injection Pressure (IP), Mix and Blend is 178MEM4.2B24. Overall corresponding variation between optimization and experimental results was found to be 7.45%.

Keywords: COME, IP, MFCT, optimization, PI, PN, PV

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787 Fabrication of a New Electrochemical Sensor Based on New Nanostructured Molecularly Imprinted Polypyrrole for Selective and Sensitive Determination of Morphine

Authors: Samaneh Nabavi, Hadi Shirzad, Arash Ghoorchian, Maryam Shanesaz, Reza Naderi

Abstract:

Morphine (MO), the most effective painkiller, is considered the reference by which analgesics are assessed. It is very necessary for the biomedical applications to detect and maintain the MO concentrations in the blood and urine with in safe ranges. To date, there are many expensive techniques for detecting MO. Recently, many electrochemical sensors for direct determination of MO were constructed. The molecularly imprinted polymer (MIP) is a polymeric material, which has a built-in functionality for the recognition of a particular chemical substance with its complementary cavity.This paper reports a sensor for MO using a combination of a molecularly imprinted polymer (MIP) and differential-pulse voltammetry (DPV). Electropolymerization of MO doped polypyrrole yielded poor quality, but a well-doped, nanostructure and increased impregnation has been obtained in the pH=12. Above a pH of 11, MO is in the anionic forms. The effect of various experimental parameters including pH, scan rate and accumulation time on the voltammetric response of MO was investigated. At the optimum conditions, the concentration of MO was determined using DPV in a linear range of 7.07 × 10−6 to 2.1 × 10−4 mol L−1 with a correlation coefficient of 0.999, and a detection limit of 13.3 × 10-8 mol L−1, respectively. The effect of common interferences on the current response of MO namely ascorbic acid (AA) and uric acid (UA) is studied. The modified electrode can be used for the determination of MO spiked into urine samples, and excellent recovery results were obtained. The nanostructured polypyrrole films were characterized by field emission scanning electron microscopy (FESEM) and furrier transforms infrared (FTIR).

Keywords: morphine detection, sensor, polypyrrole, nanostructure, molecularly imprinted polymer

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786 Design and Fabrication of ZSO Nanocomposite Thin Film Based NO2 Gas Sensor

Authors: Bal Chandra Yadav, Rakesh K. Sonker, Anjali Sharma, Punit Tyagi, Vinay Gupta, Monika Tomar

Abstract:

In the present study, ZnO doped SnO2 thin films of various compositions were deposited on the surface of a corning substrate by dropping the two sols containing the precursors for composite (ZSO) with subsequent heat treatment. The sensor materials used for selective detection of nitrogen dioxide (NO2) were designed from the correlation between the sensor composition and gas response. The available NO2 sensors are operative at very high temperature (150-800 °C) with low sensing response (2-100) even in higher concentrations. Efforts are continuing towards the development of NO2 gas sensor aiming with an enhanced response along with a reduction in operating temperature by incorporating some catalysts or dopants. Thus in this work, a novel sensor structure based on ZSO nanocomposite has been fabricated using chemical route for the detection of NO2 gas. The structural, surface morphological and optical properties of prepared films have been studied by using X-ray diffraction (XRD), Atomic force microscopy (AFM), Transmission electron microscope (TEM) and UV-visible spectroscopy respectively. The effect of thickness variation from 230 nm to 644 nm of ZSO composite thin film has been studied and the ZSO thin film of thickness ~ 460 nm was found to exhibit the maximum gas sensing response ~ 2.1×103 towards 20 ppm NO2 gas at an operating temperature of 90 °C. The average response and recovery times of the sensor were observed to be 3.51 and 6.91 min respectively. Selectivity of the sensor was checked with the cross-exposure of vapour CO, acetone, IPA, CH4, NH3 and CO2 gases. It was found that besides the higher sensing response towards NO2 gas, the prepared ZSO thin film was also highly selective towards NO2 gas.

Keywords: ZSO nanocomposite thin film, ZnO tetrapod structure, NO2 gas sensor, sol-gel method

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785 4D Modelling of Low Visibility Underwater Archaeological Excavations Using Multi-Source Photogrammetry in the Bulgarian Black Sea

Authors: Rodrigo Pacheco-Ruiz, Jonathan Adams, Felix Pedrotti

Abstract:

This paper introduces the applicability of underwater photogrammetric survey within challenging conditions as the main tool to enhance and enrich the process of documenting archaeological excavation through the creation of 4D models. Photogrammetry was being attempted on underwater archaeological sites at least as early as the 1970s’ and today the production of traditional 3D models is becoming a common practice within the discipline. Photogrammetry underwater is more often implemented to record exposed underwater archaeological remains and less so as a dynamic interpretative tool.  Therefore, it tends to be applied in bright environments and when underwater visibility is > 1m, reducing its implementation on most submerged archaeological sites in more turbid conditions. Recent years have seen significant development of better digital photographic sensors and the improvement of optical technology, ideal for darker environments. Such developments, in tandem with powerful processing computing systems, have allowed underwater photogrammetry to be used by this research as a standard recording and interpretative tool. Using multi-source photogrammetry (5, GoPro5 Hero Black cameras) this paper presents the accumulation of daily (4D) underwater surveys carried out in the Early Bronze Age (3,300 BC) to Late Ottoman (17th Century AD) archaeological site of Ropotamo in the Bulgarian Black Sea under challenging conditions (< 0.5m visibility). It proves that underwater photogrammetry can and should be used as one of the main recording methods even in low light and poor underwater conditions as a way to better understand the complexity of the underwater archaeological record.

Keywords: 4D modelling, Black Sea Maritime Archaeology Project, multi-source photogrammetry, low visibility underwater survey

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784 Potential of Sunflower (Helianthus annuus L.) for Phytoremediation of Soils Contaminated with Heavy Metals

Authors: Violina R. Angelova, Mariana N. Perifanova-Nemska, Galina P. Uzunova, Krasimir I. Ivanov, Huu Q. Lee

Abstract:

A field study was conducted to evaluate the efficacy of the sunflower (Helianthus annuus L.) for phytoremediation of contaminated soils. The experiment was performed on an agricultural field contaminated by the Non-Ferrous-Metal Works near Plovdiv, Bulgaria. Field experiments with a randomized, complete block design with five treatments (control, compost amendments added at 20 and 40 t/daa, and vemicompost amendments added at 20 and 40 t/daa) were carried out. The accumulation of heavy metals in the sunflower plant and the quality of the sunflower oil (heavy metals and fatty acid composition) were determined. The tested organic amendments significantly influenced the uptake of Pb, Zn and Cd by the sunflower plant. The incorporation of 40 t/decare of compost and 20 t/decare of vermicompost to the soil led to an increase in the ability of the sunflower to take up and accumulate Cd, Pb and Zn. Sunflower can be subjected to the accumulators of Pb, Zn and Cd and can be successfully used for phytoremediation of contaminated soils with heavy metals. The 40 t/daa compost treatment led to a decrease in heavy metal content in sunflower oil to below the regulated limits. Oil content and fatty acids composition were affected by compost and vermicompost amendment treatments. Adding compost and vermicompost increased the oil content in the seeds. Adding organic amendments increased the content of stearic, palmitoleic and oleic acids, and reduced the content of palmitic and gadoleic acids in sunflower oil. The possibility of further industrial processing of seeds to oil and use of the obtained oil will make sunflowers economically interesting crops for farmers of phytoremediation technology.

Keywords: heavy metals, phytoremediation, polluted soils, sunflower

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783 Prioritization Ranking for Managing Moisture Problems in a Building

Authors: Sai Amulya Gollapalli, Dilip A. Patel, Parth Patel K., Lukman E. Mansuri

Abstract:

Accumulation of moisture is one of the most worrisome aspects of a building. Architects and engineers tend to ignore its vitality during the designing and construction stage. Major fatalities in buildings can be caused by it. People avoid spending a lot of money on waterproofing. If the same mistake is repeated, no deep thinking is done. The quality of workmanship and construction is depleting due to negligence. It is important to do an analysis of the water maintenance issues happening in the current buildings and give a database for all the factors that are causing the defect. In this research, surveys are done with two waterproofing consultants, two client engineers, and two project managers. The survey was based on a matrix that was based on the causes of water maintenance issues. There were around 100 causes that were identified. The causes were categorized into six, namely, manpower, finance, method, management, environment, and material. In the matrices, the causes on the x-direction matched with the causes on the y-direction. 3 Likert scale was used to make a pairwise comparison between causes on each cell. Matrices were evaluated for the main categories and for each category separately. A final ranking was done by the weights achieved, and ‘cracks arriving from various construction joints’ was the highest with 0.57 relative significance, and ‘usage of the material’ was the lowest with 0.03 relative significance. Twelve defects due to water leakage were identified, and interviewees were asked to make a pairwise comparison of them, too, to understand the priorities. When the list of causes is achieved, the prioritization as per the stratification analysis is done. This will be beneficial to the consultants and contractors as they will get a primary idea of which causes to focus on.

Keywords: water leakage, survey, causes, matrices, prioritization

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782 The Relation Between Oxidative Stress, Inflammation, and Neopterin in the Paraquat-Induced Lung Toxicity

Authors: M. Toygar, I. Aydin, M. Agilli, F. N. Aydin, M. Oztosun, H. Gul, E. Macit, Y. Karslioglu, T. Topal, B. Uysal, M. Honca

Abstract:

Paraquat (PQ) is a well-known quaternary nitrogen herbicide. The major target organ in PQ poisoning is the lung. Reactive oxygen species (ROS) and inflammation play a crucial role in the development of PQ-induced pulmonary injury. Neopterin is synthesized in macrophage by interferon g and other cytokines. We aimed to evaluate the utility of neopterin as a diagnostic marker in PQ-induced lung toxicity. Sprague Dawley rats were randomly divided into two groups (sham and PQ), administered intraperitoneally 1 mL saline and PQ (15 mg/kg/mL) respectively. Blood samples and lungs were collected for analyses. Lung injury and fibrosis were seen in the PQ group. Serum total antioxidant capacity, lactate dehydrogenase (LDH), and lung transforming growth factor-1 (TGF-1) levels were significantly higher than the sham group (in all, p< 0.001). In addition, in the PQ group, serum neopterin and lung malondialdehyde (MDA) levels were also significantly higher than the sham group (in all, p 1/4 0.001). Serum neopterin levels were correlated with LDH activities, lung MDA, lung TGF-1 levels, and the degree of lung injury. These findings demonstrated that oxidative stress, reduction of antioxidant capacity, and inflammation play a crucial role in the PQ-induced lung injury. Elevated serum neopterin levels may be a prognostic parameter to determine extends of PQ-induced lung toxicity. Further studies may be performed to clarify the role of neopterin by different doses of PQ.

Keywords: paraquat, inflammation, oxidative stress, neopterin, lung toxicity

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781 Nanostructure of Gamma-Alumina Prepared by a Modified Sol-Gel Technique

Authors: Débora N. Zambrano, Marina O. Gosatti, Leandro M. Dufou, Daniel A. Serrano, M. Mónica Guraya, Soledad Perez-Catán

Abstract:

Nanoporous g-Al2O3 samples were synthesized via a sol-gel technique, introducing changes in the Yoldas´ method. The aim of the work was to achieve an effective control of the nanostructure properties and morphology of the final g-Al2O3. The influence of the reagent temperature during the hydrolysis was evaluated in case of water at 5 ºC and 98 ºC, and alkoxide at -18 ºC and room temperature. Sol-gel transitions were performed at 120 ºC and room temperature. All g-Al2O3 samples were characterized by X-ray diffraction, nitrogen adsorption and thermal analysis. Our results showed that temperature of both water and alkoxide has not much influence on the nanostructure of the final g-Al2O3, thus giving a structure very similar to that of samples obtained by the reference method as long as the reaction temperature above 75 ºC is reached soon enough. XRD characterization showed diffraction patterns corresponding to g-Al2O3 for all samples. Also BET specific area values (253-280 m2/g) were similar to those obtained by Yoldas’s original method. The temperature of the sol-gel transition does not affect the resulting sample structure, and crystalline boehmite particles were identified in all dried gels. We analyzed the reproducibility of the samples’ structure by preparing different samples under identical conditions; we found that performing the sol-gel transition at 120 ºC favors the production of more reproducible samples and also reduces significantly the time of the sol-gel reaction.

Keywords: nanostructure alumina, boehmite, sol-gel technique, N2 adsorption/desorption isotherm, pore size distribution, BET area.

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780 Role of the Marshes in the Natural Decontamination of Surface Water: A Case of the Redjla Marsh, North-Eastern Algerian

Authors: S. Benessam, T. H. Debieche, A. Drouiche, S. Mahdid, F. Zahi

Abstract:

The marsh is the impermeable depression. It is not very deep and presents the stagnant water. Their water level varies according to the contributions of water (rain, groundwater, stream etc.), when this last reaches the maximum level of the marsh, it flows towards the downstream through the discharge system. The marsh accumulates all the liquid and solid contributions of upstream part. In the North-East Algerian, the Redjla marsh is located on the course of the Tassift river. Its contributions of water come from the upstream part of the river, often characterized by the presence of several pollutants in water related to the urban effluents, and its discharge system supply the downstream part of the river. In order to determine the effect of the marsh on the water quality of the river this study was conducted. A two-monthly monitoring of the physicochemical parameters and water chemistry of the river were carried out, before and after the marsh, during the period from November 2013 to January 2015. The results show that the marsh plays the role of a natural purifier of water of Tassift river, present by drops of conductivity and concentration of the pollutants (ammonium, phosphate, iron, chlorides and bicarbonates) between the upstream part and downstream of the marsh. That indicates that these pollutants are transformed with other chemical forms (case of ammonium towards nitrate), precipitated in complex forms or/and adsorbed by the sediments of the marsh. This storage of the pollutants in the ground of the marsh will be later on a source of pollution for the plants and river water.

Keywords: marsh, natural purification, urban pollution, nitrogen

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779 Fluoranthene Removal in Wastewater Using Biological and Physico-Chemical Methods

Authors: Angelica Salmeron Alcocer, Deifilia Ahuatzi Chacon, Felipe Rodriguez Casasola

Abstract:

Polycyclic aromatic hydrocarbons (PAHs) are produced naturally (forest fires, volcanic eruptions) and human activity (burning fossil fuels). Concern for PAHs is due to their toxic, mutagenic and carcinogenic effects and so pose a potential risk to human health and ecology. Therefore these are considered the most toxic components of oil, they are highly hydrophobic, making them easily depositable on the floor, air and water. One method of removing PAHs of contaminated soil used surfactants such as Tween 80, which it has been reported as less toxic and also increases the solubility of the PAH compared to other surfactants, fluoranthene is a PAH with molecular formula C16H10, its name derives from the fluorescence which presents to UV light. In this paper, a study of the fluoranthene removal solubilized with Tween 80 in synthetic wastewater using a microbial community (isolated from soil of coffee plantations in the state of Veracruz, Mexico) and Fenton oxidation method was performed. The microbial community was able to use both tween 80 and fluoranthene as carbon sources for growth, when the biological treatment in batch culture was applied, 100% of fluoranthene was mineralized, this only occurred at an initial concentration of 100 ppm, but by increasing the initial concentration of fluoranthene the removal efficiencies decay and degradation time increases due to the accumulation of byproducts more toxic or less biodegradable, however when the Fenton oxidation was previously applied to the biological treatment, it was observed that removal of fluoranthene improved because it is consumed approximately 2.4 times faster.

Keywords: fluoranthene, polycyclic aromatic hydrocarbons, biological treatment, fenton oxidation

Procedia PDF Downloads 235