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Determinants of Environmental Degradation in Thailand: Empirical Evidence from ARDL and Wavelet Coherence Approaches Full text
2021
Adebayo, T. S. | Akinsola, G. D. | Odugbesan, J. A. | Olanrewaju, V. O.
This paper explores long-run and causal effects of financial development, real growth, urbanization, gross capital formation and energy consumption on CO2 emissions in Thailand by utilizing recent econometric techniques. The study employs ARDL technique to examine the long and short run interconnection between CO2 emissions and the regressors. Furthermore, we employ the FMOLS, DOLS and CCR as a robustness check to the ARDL long-run estimator. The study use time-series data spanning from 1971 to 2016. The study also utilizes the wavelet coherence technique to collect information on the association and causal interrelationship among these economic variables at different frequencies and timeframes in Thailand. The study objectives are structured to answer the following questions: (a) does the selected macroeconomic indicators impact CO2 emissions in Thailand? (b) if so, why? Findings reveal; (i) Negative and insignificant link between CO2 emissions and urbanization. (ii) GDP growth affects CO2 emissions positively. (iii) The interconnection between CO2 emissions and energy usage is positive. (iv) Gross capital formation impact CO2 emissions positively. (v) Positive interconnection exists between financial development and CO2 emissions in Thailand. Additionally, the wavelet coherence result provides a supportive evidence for the ARDL long run result. Based on these findings, policy directions were suggested.
Show more [+] Less [-]Assessment of Annual Effective Dose Associated with Radon in Drinking Water from Gold and Bismuth Mining area of Edu, Kwara, North-central Nigeria Full text
2021
Ajibola, T.B. | Orosun, M.M. | Lawal, W. A. | Akinyose, F.C. | Salawu, N.B.
The aim of this paper is to assess the radon concentration of surface and ground waters around Bismuth mining site located in Edu, Kwara State, Nigeria, in order to ascertain its radiological risk. Seventeen (17) water samples were collected and analyzed for radon concentration using a calibrated Rad7-Active Electronic Detector Durridge. The Radon concentration for surface water ranged from 16.23±3.45 Bq/l to 24.71±4.51 Bq/l with a mean of 19.14±3.98 Bq/l while that of ground water ranged from 21.59±3.29 to 27.93±5.74 Bq/l with a mean of 24.16±4.21 Bq/l. The concentration results were used to estimate the annual effective doses. The mean total annual effective dose obtained by summing the dose due to inhalation and ingestion for surface water samples were 187.97 μSvy-1, 257.84 μSvy-1 and 292.77 μSvy-1 for adult, children and infants respectively. Also, the mean effective doses for ground water samples were of 237.25 μSvy-1, 325.44 μSvy-1 and 369.53 μSvy-1 for adult, children and infants respectively. Both the radon concentration and the effective dose due to its inhalation and ingestion were higher than the recommended limit of 11.1 Bq/l and 100 μSvy-1 respectively for all samples. Therefore, consumption of the water in this area poses serious health risk as the water is not safe for all age groups considered. Therefore, it is advised that the water from both sources be treated before consumption.
Show more [+] Less [-]The Impact of RDF Valorization on the Leachate Quality and on Emissions from Cement Kiln (Case Study of a Region in Morocco) Full text
2021
Ouigmane, Abdellah | Boudouch, Otmane | Hasib, Aziz | Ouhsine, Omar | Abba, El Hassan | Isaifan, Rima J. | Berkani, Mohamed
Energy recovery is a sustainable method of municipal solid waste (MSW) management. The co-incineration of refuse derived fuel (RDF) has shown several economic and environmental advantages. The objective of this research is to assess the impact of RDF recovery on leachate quality using leachate tests and calculation of greenhouse gases (GHG) reduction in the kilns of a cement plant. The qualitative results of the eluate show that there is an impact on leachate quality depending on the type of waste. The values of the chemical oxygen demand (COD), biological oxygen demand (BOD5), electrical conductivity and pH of the leachate from the raw waste after 120 hours of leaching are 29.33 gO2/kg DM, 14.00 g O2/kg DM, 4.27 ms/cm and 7.57. On the other hand, the values of the same quality parameters of the eluate generated by the waste without RDF are 19.33 g O2/kg DM, 20.67 g O2/kg DM, 2.77 ms/cm and 7.13; respectively. The calculation of GHG reduction shows that the substitution of 83,000 tonnes per year of petroleum coke by 15% of RDF (25,493 tonnes per year) can reduces 28,970 tCO2 eq.
Show more [+] Less [-]Efficacy of Photocatalytic HEPA Filter on Reducing Bacteria and Fungi Spores in the Presence of UVC and UVA Lights Full text
2021
Mousavi, Tahereh | Golbabaei, Farideh | Kohneshahri, Mehrdad Helmi | Pourmand, Mohammad Reza | Rezaie, Sassan | Hosseini, Mostafa | Karimi, Ali
The Indoor Air Quality (IAQ) of a hospital is very important to properly protect both patients and the staff against hospital infections. The present study aims at evaluating the efficiency of photocatalytic filters as well as the impact of important factors such as the type of UV wavelength (UVC, UVA) with different intensities and loading rates of TiO2 in HEPA Filters on reducing airborne microorganisms. For so doing, it has prepared photocatalytic filters by dipping them into 2% and 4% titanium dioxide suspensions as low and high loading, respectively. The experiments have been carried out on four species’ microorganisms, namely Epidermidis, Subtilis, Niger, and Penicillium. Fungi and bacteria suspensions have been prepared with concentrations of 106, 107 CFU/m3, respectively. In terms of microorganism removal, the efficiency of HEPA filters in both types of TiO2 loading and UVC and UVA radiations with two intensities at three times intervals (60, 90, and 120 min) have been investigated. Results show that lower penetration microorganism belong to PCO (TiO2 + UV), compared to photolysis (UV alone) at all intervals of UV radiation. TiO2 loading has no significant effect on percentage removal in all microorganisms. The percentage penetration of microorganisms under UVC radiation is lower than UVA radiation. Also, increasing the radiation intensity in both types of UV shows that it has higher effectiveness for removing bacteria and fungi. Therefore, the use of photocatalytic HEPA filters with UVC radiation can play an influential role in reduction of the microorganisms in different places such as hospitals, cleanrooms, etc.
Show more [+] Less [-]Effect of Biochar Amended Vermicomposting of Food and Beverage Industry Sludge along with Cow dung and Seed Germination Bioassay Full text
2021
Tasnim, Umme Fariha | Shammi, Mashura | Uddin, Md. Khabir | Akbor., Md. Ahedul
Transformation of food and beverage industrial sludge into vermicompost into value-added product simultaneously can control gaseous emission. Addition of biochar in the vermicomposting as a bulking agent increases fertilizer value. This research aimed to investigate the effect of biochar amendment on vermicomposting of the food and beverage industry sludge (FBIS) and cow dung (CD) in a different ratio using earthworm Eisenia fetida. We had further investigated the survival rate of E. fetida and the cocoon productions after 35 days of the vermicomposting. Besides, we have also evaluated the seed germination bioassay using Malabar spinach (Basella alba) to determine the toxicity and maturity of produced compost. The survival and cocoon production of E. fetida were higher in vermicompost amended with 10% biochar. Vermicomposting with biochar resulted in a slight pH shift. Reduction in organic carbon (OC) percentage not so significant in biochar added FBIS and CD. An increase in phosphorus and potassium content and a decrease in nitrogen percentage observed; vermicomposting with biochar resulted in higher seed germination, root elongation, and germination index than vermicomposting without biochar.
Show more [+] Less [-]Extraction of Keratin from Human Hair Waste as Adsorbent: Characterization, Thermodynamic and Kinetic Study for Removal of Chromium (VI) ions Full text
2021
Abbasi, Fereshteh | Farrokhnia, Abdolhadi | Abbasi, Zahra
In this paper, human hair, as a waste material, was utilized in order to prepare keratin nanoparticles. The characterization of keratin nanoparticles was performed applying Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and X-Ray diffraction (XRD). The average diameter of keratin nanoparticles was found to be 63.7 nm, using particle size analyzer. Subsequently, the keratin nanoparticles were employed for Cr (VI) ions adsorption. The batch experiment was carried out to find the optimum conditions; i.e. contact time, pH, adsorbent dose and initial concentration of Cr (VI) ions. The adsorption capacity was extremely pH-dependent, and the maximum adsorption of Cr (VI) happened in the acidic pH range. The results demonstrated that the maximum adsorption capacity, obtained in acidic pH, was 161.29 mg/g. The equilibrium data were well fitted by Freundlich isotherm. The kinetic studies were performed with the Lagergren’s first-order, Pseudo-second order, Elovich, and Intra-particle diffusion models. In this sense, in order to describe kinetic data, we came to this understanding that Pseudo-second order model was the best choice. The thermodynamic parameters of the adsorption process indicated that the Cr (VI) adsorption on keratin nanoparticles is endothermic and spontaneous.
Show more [+] Less [-]Identification and Characterization of Phenolic and Flavonoids Compounds Extracted from Tunisian Pomegranate Fruit Peel Exposed to Air Pollution: Gabes City, Tunisia Full text
2021
Ben Amor, Afef | Ben Atia Zrouga, Khaoula | Chaira, Nizar | Ben Yahia, Leila | Nagaz, Kamel
The pomegranate (Punica granatum) fruit peel exposed to mixture air pollutants were collected from two sites with different air quality around the industrial area of Gabes city, Tunisia. The first site presented the ‘Polluted site’, which is situated in the oasis close to the industrial area. While, the second site referred to the ‘Control site’ located at 37 km from the industrial area. Using HPLC ES-MS, 21 phenols were identified and quantified in methanol extract from pomegranate fruit peel. The results showed that various phytochemical substances, including phenols acids and flavonoids, were identified and quantified in the peel extract. The polyphenols content and the flavonoids contents in peel obtained from polluted site were higher than that collected from the control site. The concentrations of the identified polyphenols were ranged between 0.39 and 7803.68 mg/ kg DW. The stimulation of some free phenolic compounds such syringic acid, transfrulic acid, epicatechin, rutin and quercetin was enregistred only in peel collected from contaminated environment. The quali-qualitative changes between sites are probably related to the difference in the air quality. The increase of polyphenols could be implicated during adaptive mechanisms under air pollution. Phenolic composition changes in Punica granatum peel could be also suggested as useful approach air pollution monitoring.
Show more [+] Less [-]Water Quality Assessment in Urban Wetlands and Suitability for Fish Habitat: A Case Study Full text
2021
Dixit, Arohi | Siva Siddaiah, Neelam | Singh Chauhan, Jogindar | Ullah Khan, Waseem
In this study, water from three urban wetlands of Gurugram – Sultanpur (WS), Damdama (WD), and Basai (WB), was studied for various physicochemical parameters to assess their suitability for the healthy survival of fishes and the results were compared with the limits of these parameters for fish farming. The parameters studied were colour, temperature, pH, alkalinity, hardness, Ca2+- Mg2+ ratio, NO3-, Cl-, SO42-, PO43-, and heavy metals (Fe, Mn, Cr, Cu, Zn, Ni and Pb). The results of the study indicate the majority of studied parameters are beyond the desirable limits in WB; thus, water is most unsuitable for fishes in WB. WB is unsuitable for parameters: colour, alkalinity, hardness, Ca -Mg ratio, NO3-, Cl-, SO42-, PO43-, Cr, Cu, Fe, Mn, Ni and Zn. WS needs consideration for temperature, NO3-, Cu, Ni and Zn, whereas WD needs improvement in temperature, TDS, NO3-, Cr, Cu, Fe, Mn, Ni and Zn concentration for better fish growth. Most of the parameters are high in summer as compared to winter, which is due to the dilution after rainfall. Hence, we recommend timely action for effective measures to improve the water quality of wetlands and their regular monitoring for improved fish habitat.
Show more [+] Less [-]Assessment of Groundwater Based Public Drinking Water Supply System of Kamrup District, Assam, India using a Modified Water Quality Index Full text
2021
Goswami, Jayanta | Bhattacharjya, Rajib Kumar
This work aims to assess the Water Quality Index (WQI) of the groundwater-based public drinking water supply system of Kamrup District (Rural) of Assam, India. For assessing WQI, water samples have been collected, both raw water and treated water, from seventy-eight public drinking water supply projects over the district for comprehensive physicochemical analysis. The WQI was calculated based on the weightage derived from the literature survey and based on the doctors’ weightage. The derived WQI showed that the water quality falls from poor to very poor quality. However, the concentration of the water quality parameters except Iron, Fluoride, and Manganese are within the permissible limit in all the water supply projects. It shows that the WQI calculated based on the weightage derived, as stated above, is not displaying the actual water quality of the supplied water. As such, a modified method is proposed to calculate the WQI of the supplied water considering the permissible limit of the parameters in deriving the weightage for the parameters. The WQI values calculated using the modified method falls in the range of good water quality to poor water quality and shows the true water quality of the supplied water. The statistical analysis of the water quality parameters and WQI shows that the WQI has a very high correlation with Manganese with a coefficient of correlation value of 0.86, followed by 0.4 with Chloride and 0.34 with Fluoride.
Show more [+] Less [-]Assessment of water quality of Oum Er Rabia River by Microbiological Quality Index and Water Quality Index Full text
2021
Abba, El Hassan | Idrissi, Imam | Bennani, Younes | El Yaacoubi, Adnane | Cherroud, Sanae | Ainane, Tarik | Khaffou, Mhamed
Water resource management requires simple tools to enable managers to make decisions. This is the case for water quality indices that provide access to clear, synthetic and well-targeted information. In this study, we have chosen two indices based on two different approaches, the Microbiological Quality Index (MQI), which is determined from bacteriological analyses of water, and the Water Quality Index (WQI), which is based on physicochemical parameters. The Water Quality Index (WQI) shows a longitudinal upstream-downstream variation and ranges from is between five (5) (Null Faecal Contamination) at sampling point P1 and 3.4 (Moderate Fecal Contamination) at P2. The Water Quality Index (WQI) ranges from a low of 14.08 (excellent water quality) at the P1 level to a high of 93.05 at the P2 level (poor water quality) receiving wastewater discharges. The WQI results for P3 and P4, show that the water is of good quality (downstream of P2), which shows the degree of self-purification of the Oum Er Rabia River, regardless of the sampling period. Finally, the results of the MQI corroborate those obtained with the WQI for the water quality of the different sampling points.
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