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Enhanced Bioremediation of Brass Crude-Oil (Hydrocarbon), Using Cow Dung and Implication on Microbial Population
2018
Olawepo, Gabriel | Ogunkunle, Clement | Adebisi, Olusoji | Fatoba, Paul
The present study has used soil samples from Nigeria, contaminated with Brass crude-oil, to determine its biodegradation through enhanced biostimulation with cow dung and periodic aeration. Over a period of twenty-eight days, the hydrocarbon-utilizing bacteria (HUB) and hydrocarbon-utilizing fungi (HUF) have been counted and identified. Results from biodegradation of the brass crude-oil over the aforementioned period show that amended crude-oil-spiked soil has had 54.82% degradation while for amendment and periodic turning this has been 55.90%, not significantly higher than the former at p≤0.05. Also degradation of spiked soil without cow dung amendment has been 16.13%. The identified HUB are Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, and Streptococcus thermophillus, with individual occurrence of 18.52% as well as Proteus vulgaris and Micrococcus luteus with 11.11% and 14.81% occurrence, respectively. Also, the occurrence rate of HUF like Aspergillus flavus, A. niger, Penicillium chrysogenum, Trichothecium roseum, and Penicillium citrinum have been 15.63% each;whilefor Alternaria alternata and Neurospora crazza it has been 6.25% and for Saccharomyces cerevisae and A. fumigatus, 9.38%and3.13%, respectively. The study concludes that amendment with cow dung and periodic turning of the soil enhance degradation of Brass crude-oil significantly. What is more, aeration by periodic turning slightly improves degradation only with cow dung treatment on Days 21 and 28.
Afficher plus [+] Moins [-]Environmental Situation of an Agricultural Area in Akure, Nigeria, Based on Physico-Chemical Properties of Rainwater
2018
Abulude, Francis | Ndamitso, M.M. | Abdulkadir, A
Acid rain still poses a global problem today, exerting many adverse effects on man, animal, and materials. As its research question, the present study tries to find out whether or not acid rains exist in Akure, Nigeria. For so doing, it determines physico-chemical properties of rain water samples, namely pH, temp, Electrical Conductivity (EC), TDS, acidity, SO4-, NO2-, Cl-, and Free CO2. According to the results, the pH ranged between 6.0 and 7.8, never falling below 5.6 which is an indication of acid rain. Also, the minimum EC was 3µS/cm and the maximum, 201µS/cm. Moreover, TDS was between 1 and 100mg/L, while Free CO2 had a mean of 23.00 and Standard Deviation of 6.16. The dominant ion was SO4- (10-11%), followed by NO3-, and Cl-. Results from the first six months (July-December 2015) reveal slight correlations in the following: TDS with pH (0.532), EC and pH (0.501), Temp and Free CO2 (0.59), whereas strong correlations have been recorded in the following parameters: Acidity with pH (0.71) and Temperature (0.69), NO2- with pH (0.96) and acidity (0.96), SO4- with temp (0.68) and NO2- (0.83), and finally Cl- with Free CO2 (0.61), NO2- (0.73), and Cl- (0.65). It can be concluded that in the environment under this study there have been no acid rain within the period.
Afficher plus [+] Moins [-]Acoustic Environment in the Bus: an Empirical Study
2018
Swain, Bijay | Goswami, Shreerup
Traffic snarl-up or traffic jam is a common phenomenon in Puri, one of the imperative pilgrimage sites for Hindus as well as a popular tourist destination in India. Traffic congestion inevitably produces traffic noise, in turn annoying the drivers, leading to road rage. Keeping this in mind, the present article has monitored and assessed different noise descriptors in 7 different types of buses, totally involving 35 buses in and around Puri, for three years, from 2014 to 2016. The minimum and maximum noise levels have been more than 65.3 dB and 90 dB, respectively. Also, Leq is beyond 80dB, demonstrating a noisy environment inside the bus. The result of Karl Pearson’s Correlation Co-efficient clearly indicates that in general, the noise levels have gradually increased from 2014 to 2016. Furthermore, it has conducted a survey to reveal opinions of 156 passengers and 50 drivers of the buses concerning their annoyance from noise pollution.
Afficher plus [+] Moins [-]Common Waterborne Diseases Due to Bacterial, Fungal and Heavy Metal Contamination of Waters: A Case Study from Nacharam Area of Hyderabad, India
2018
Das Sharma, Mala | Padmalatha, P.
Nacharam and its surroundings, located inside the city of Hyderabad in Telangana State, India, is vulnerable to water-borne diseases; therefore, the present research works on concentrations of dissolved hexavalent chromium (57-263 mgL-1), lead (34-65 mgL-1), cadmium (2.3-22.4 mgL-1), and nickel (from below detection limit to 6.5 mgL-1) in different surface water and groundwater bodies of this area. Results indicate that with the exception of nickel, the majority of studied water bodies and aquifers of the area are contaminated, to variable degrees, with dissolved heavy metals. Also health-affecting bacterial and fungal colonies have been found in drinking water and groundwater bodies of the area. These findings collectively point at impending health threats to the residents of the area, thus this study has conducted a health survey, whose data indicate that about two third of the residents are affected by waterborne ailments, including hair fall, skin rashes, tooth decay, diarrhea, and joint pain. Hair fall is one of the major problems affecting about 40% of the area population. Other waterborne health-related issues are faced by relatively smaller numbers of residents (10% or less). Based on the results from this study, it is recommended not only to conduct periodic analyses of water samples used for drinking and other purposes, which would assist the government and local authorities in taking necessary steps to prevent groom and spread of microorganisms, but also to monitor other anthropogenic activities, potentially capable of contaminating water sources, .
Afficher plus [+] Moins [-]Modeling of Air Pollutants’ Dispersion by Means of CALMET/CALPUFF (Case Study: District 7 in Tehran city).
2018
Joneidi, Neda | Rashidi, Yousef | Atabi, Farideh | broomandi, parya
The current study aims at modelling the dispersion of two pollutants, namely CO (carbon monoxide) and SO2 (sulfur dioxide) released from District 7 of Tehran Municiaplity, from 20 main line sources, by means of CALPUFF modeling system. CALPUFF is a non-steady state puff modeling software which employs meteorological, terrain, and land-use data to effectively simulate air pollutants' dispersion from a given source. CALMET software has been applied to provide meteorological conditions within the study domain. The study has been carried out on September 30, 2012 and shows that the modeled concentrations have been below both Iranian air ambient standard and NAAQS standard for CO and SO2. It also compares the measurements from the monitoring station of Setad Bohran, showing that the simulated hourly mean concentrations of the SO2 and CO do not follow similar temporal patterns for measurement values. For the absolute value, model results seem to be highly underestimated, compared to the monitored data (R2 = -0.41).
Afficher plus [+] Moins [-]Experimental and Theoretical Study on the Ability of Microbial Fuel Cell for Electricity Generation
2018
Ali, Ahmed | Al-Mussawy, H.A. | Hussein, M.J. | Hamadi, N.J.
The present study aims at designing a promising Microbial Fuel Cell (MFC) to utilize wastewater in order to generate electricity. Two types of salt bridge have been used in MFC (KCl and NaCl). The maximum electricity generation with 1M KCl and NaCl has been 823 and 713 mV, respectively. Varied salt concentrations (0.5M, 1M, 2M, and 3M) of salt bridge in MFC have been analyzed with different factors like temperature, type of electrode, configuration, and surface area of electrode being studied. The optimum temperature is found to be 32Co, with the optimum type of electrode being graphite rod, while the optimum configuration and surface area of electrode is graphite plate with surface area of 183.6 cm2. Artificial Neural Network (ANN) has been employed to predict voltage production of MFC and compare it with the experimental voltage. Multiple correlation methodology has optimized the voltage production with the correlation coefficient (R2) being 0.999.
Afficher plus [+] Moins [-]Optimization of Soil Aquifer Treatment by Chemical Oxidation with Hydrogen Peroxide Addition
2018
Usman, Muhammad | Waseem, Muhammad | Mani, Nithish | Andiego, George
Trace organic compounds (TrOCs), mostly found in secondary effluents have a potential impact on the environment including surface water, groundwater and especially aquatic ecosystems. This study focuses on oxidation of five selected TrOCs in column experiments simulating soil aquifer treatment (SAT) integrated with Fenton like reaction using granular ferric hydroxide (GFH) as a catalyst. In order to determine the effectiveness of removing TrOCs by water through this approach, experiments were carried out with ultrapure water containing different target compounds at pH 6 using different dosages of hydrogen peroxide and catalyst. In this study the optimal concentration of hydrogen peroxidefor removal of TrOCs was found to be 200 mg/L. However, observed overall removal was low for each target compound. Moreover, little increase in chemical oxidation of micropollutants was observed by increasing dosage of the catalyst. For an optimum concentration of hydrogen peroxidethe removal of 33, 34, 28, 29 and 35% were observed for benzotriazole, carbamazepine, phenytoin, primidone and meprobamate, respectively in 5h with a hydraulic retention time of 3h, respectively. Therefore, this treatment scheme might not be a promising option for oxidation of secondary effluents. Thus, other treatment options, such as decrease of pH, recirculation of effluent through columns to increase the hydraulic retention times, other types of catalyst and higher dosage of hydrogen peroxide need to be considered for more efficient removal of TrOCs within SAT integrated with Fenton-like.
Afficher plus [+] Moins [-]Potential Assessment of Geomorphological Landforms of the Mountainous Highland Region, Haraz Watershed, Mazandaran, Iran, Using the Pralong Method
2018
Amiri, Mohammadjavad | Nohegar, Ahmad | Bouzari, Shahrzad
As the largest service industry in the world, tourism plays a special role in sustainable development. Geomorphic tourism is known to be a segment of this industry with lower environmental impact and underlying causes that explain lower demand; therefore, it is essential to study, identify, assess, plan, and manage natural tourist attractions. As such, the present study assesses the ability of geomorphological landforms of Haraz watershed, one of the major tourism areas of Iran. In this regard, the features of geomorphologic landforms, including Mount Damavand, the Damavand Icefall, Shahandasht Waterfall, Larijan Spa, and Deryouk Rock Waterfall in different parts of the Haraz watershed have been compared from the standpoint of geotourism features. To assess these landforms, geological maps, topographic and aerial photos, satellite imagery, Geographic Information Systems (GIS), and data field have been used as research tools. Evaluation results demonstrate that the average of scientific values in these landforms’ catchment (with 0.76 points) has been greater than the average of other values. These high ratings show the landforms’ potentials to be informative to those examining them for the purpose of education as well as tourist attraction. Through proper planning and understanding of its both merits and demerits, this type of tourism can play an important role in national development and diversify regional economies.
Afficher plus [+] Moins [-]Preparation and Characterization of Nano-lignin Biomaterial to Remove Basic Red 2 dye from aqueous solutions
2018
azimvand, jafar | didehban, Khadijeh | mirshokraie, s.ahmad
The present study prepares alkali lignin (AL) via acidification of black liquor, obtained from a pulp and paper factory. The average molecular weight of AL (equal to 2,530 g/mol) has been determined with gel permeation chromatography. AL has been modified by ethylene glycol, while lignin nanoparticles (LN) has been prepared through acid precipitation technology, their size being assessed by means of DLS to show that the average diameter of the nanoparticles at pH = 4 has been 52.7 nm. Afterwards, it has used AL and LN to remove Basic Red 2 (BR2) from aqueous solutions. The absorbent structures and morphologies of AL and LN have been investigated using SEM, and FT-IR spectroscopy. The optimal conditions for the absorption of AL and LN, using 0.1 gr of the absorbent, include 100 min of duration, at pH of 7, and an initial dye concentration amounting to 100 mg/L. Furthermore, the absorption amount has been mathematically described as a function of experimental parameters, modeled by means of Response Surface Methodology (RSM). A central composite design (CCD) has been applied to evaluate the impacts of four independent variables. Optimum absorption values, obtained via empirical methods, completely match with the values, calculated by the program called Design-Expert. Both absorbent AL and LN show agree with Langmuir Isotherm with maximum absorption capacities of AL and LN being 55.2 mg/gr and 81.9 mg/gr, respectively. The experimental results show that both absorbent LN and AL follow both pseudo-second kinetic and the intraparticle diffusion models.
Afficher plus [+] Moins [-]Assessment of Heavy Metals and Microbial Load of Groundwater Samples from Ibadan Metropolis Nigeria
2018
Salaudeen, I.A. | Ogunbamowo, Paul | Rasheed-Adeleke, A.A. | Olaniyi, A.A.
The present study investigates groundwater quality in terms of heavy metals level and microbial contamination as well as the impact of bleaching powder on microbial load of groundwater samples in close proximity to a surface water body inside selected areas of Ibadan Nigeria. To do so, it collects nine water samples from three boreholes and six hand-dug wells from six locations, namely Eleyele, Wofun-Olodo, Oluyole Industrial Estate, Ogunpa, Olorunsogo, and Ojoo, keeping them in 750 mL plastic bottles. The samples are then divided by two, giving a total amount of 18 samples, with 3 and 6 duplicates apiece being treated with bleaching powder and the rest remaining untreated. Both sample sets have been analysed for water quality parameters such as pH, biochemical oxygen demand, and chemical oxygen demand, assessed using standard methods. The coliform count has been determined, using the pour plate method while heavy metal has been set by means of Atomic Absorption Spectrophotometer (AAS) after nitric acid digestion. Results show that the pH ranges within 6.0-6.5, BOD within 1.67-4.33mg of O2/L, and COD within 2.93-9.43, while heavy metal concentration is from 0.013 to 0.047 mg/L for lead, ND to 0.023 mg/L for chromium, and ND to 0.010 for cadmium. What is more, the coliform count in the samples is between 0.00 and 913.33 CFU/mL. Most of the samples exceed the WHO limits for heavy metals in drinking water, having significant levels of microbial contamination. Bleaching powder treatment alleviated the level of pollution to varying degrees; therefore, constant monitoring of groundwater source and treatment before drinking is of utmost importance.
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