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Correlation Study of Meteorological Parameters and Criteria Air Pollutants in Jiangsu Province, China Full text
2022
Johnson, Anbu Clemensis
Air pollution is a global issue and meteorological factors play an important role in its transportationand regional concentration. The current research is aimed to analyse the variations in meteorologicalparameters in a seasonal and geographical location context in the Jiangsu province of China, and itscorrelation with the six criteria air pollutants, and air quality index (AQI). The present analysis willsupplement the limited understanding on the relation between the regions prevalent climatic conditionsand atmospheric pollution. The meteorological data analysis showed Suzhou city located in thesouthern region of the Jiangsu province with high average temperature, relative humidity, and rainfall.Maximum values of temperature, UV index, sunshine, relative humidity, and rainfall occurred duringsummer, while air pressure in winter. High values of all meteorological parameters occurred in thenorthern and southern region of the province. The data correlation study revealed AQI to havenegative correlation with most meteorological parameters, and positive correlation with air pressure inall cities.
Show more [+] Less [-]High Content of Sulfur in Liquid Stream Removal via new Carbonous Nano Adsorbent: Equilibrium, Kinetic study Full text
2022
Meshkat, Seyyed Salar | Hosseini Dastgerdi, Zeinab | Abkhiz, Vahid | Hagh Shenas, Asieh
This research evaluates dibenzothiophene (DBT) adsorptive removal from the liquid stream on the graphitic carbon nitride (GCN) as a synthesized adsorbent at 25 0C with 3 g for 600 min. The morphological properties of GCN have been investigated by Brunauer–Emmett–Teller (BET), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD). The study of the characteristic properties of nano adsorbent proves the suitability of the synthesized GCN in mercaptan adsorption process with the obtained data showing a good agreement with Freundlich model. The equilibrium capacity of DBT adsorption has been calculated at about 39.1 mg/g. This has also been 25.8 mg/g for TBM (tertiary butyl mercaptan). The adsorption capacity has increased by adding to the adsorbent dosage. Thermodynamic studies expose the negative values for ΔS0 (-8.99 kJ/mol. K), ΔH0 (-21.05 kJ/mol), and ΔG0 (8.91 kJ/mol), which demonstrate that DBT adsorption has been a natural exothermic process. In addition, this experiment verifies that the substitution of N into the carbon structure improves the DBT removal efficiency in comparison with pristine CNT as an adsorbent. The removal efficiency of DBT onto GCN has been approximately 80%, i.e. 20% higher than that of pure CNT. Results show that the adsorption capacity of DBT as a cyclic source of mercaptan has been higher than Tertiary butyl mercaptan (TBM) as a liner one. The DBT adsorption mechanism is done by π–π electron interactions between the aromatic structures of DBT, lone-pair electrons of the S atoms, and the pyridinic GCN planes band.
Show more [+] Less [-]Removal of Iron from Aqueous Solution by using Typha australis Leaves as Low Cost Adsorbent Full text
2022
N’Dah, Fatimetou Mohamed | Sid’Ahmed Kankou, Mohamed | Abdallahi Bollahi, Mohamed | N’diaye, Abdoulaye Demba
Iron removal from aqueous solution via ultrasound-assisted adsorption using Typha australis leaves as low cost adsorbent had been studied. The effects of various experimental parameters like mass of the Typha australis adsorbent and contact time have been investigated using a batch experiment. The adsorption kinetic data were analyzed using the Pseudo First Order (PFO) and Pseudo Second Order (PSO) models. The adsorption modeling was carried out using the Langmuir, Freundlich and Redlich-Peterson adsorption models. For kinetic study, the adsorption process fitted the PSO model and agreed with chemisorption. Both the Langmuir and Redlich–Peterson models were found to fit the adsorption isotherm data well, but the Redlich– Peterson model was better. The maximum adsorption capacity from the Langmuir model (qmax) was 0.84 mg/g. The results of the present work showed that the Typha australis leaf, without any treatment has a good potential for iron removal from aqueous solutions via ultrasound-assisted adsorption.
Show more [+] Less [-]Remediation of Contaminated Water with Chromium VI by Sorption in Surface-activated-nanocellulose spheroids Full text
2022
Ossa-Paredes, Renata | Bastidas, Bernardo | Carvajal-Barriga, Enrique Javier
Chromium VI is a frequent pollutant of industrial liquid effluents. It is a substance classified as a carcinogen group I. In this study, a Cr VI sorption mechanism was developed by using nanocellulose spheroids (hydrogel) obtained from ivory nut. Cr VI was detected in water by a colorimetric method, using 1, 5-diphenylcarbazide at λ 540 nm. Then, the sorption capacity of nanocellulose spheroids was tested by varying the solution's pH and temperatures. The outcome of the experiment shows that the most efficient pollutant’s adsorption conditions are occur at pH 4 and 25 °C. Removal percentages of Cr VI reached 91.29% (+/-1.36) and 95.33% (+/- 0.86). Additionally, the sorption kinetics showed that the adsorption reaction on the material reaches its equilibrium 20 to 30 minutes after the reaction starts. Finally, an analysis of adsorption isotherms showed a high adjustment with the Langmuir and Freundlinch isotherms. In this frame, this work’s results show that nanocellulose beads are an interesting alternative to efficiently reduce Cr VI from industrial and drinking water.
Show more [+] Less [-]An Assessment of Sea Surface and Seabed Macro Plastic Density in Northeastern Mediterranean Sea Full text
2022
Yılmaz, Ayşe Bahar | Demirci, Aydın | Akar, Özkan | Kılıç, Ece | Uygur, Necdet | Şimşek, Emrah | Yanar, Alper | Ayan, Onur Alptekin
Increasing plastic usage pose a significant threat to the marine environment. Many studies have been conducted to examine the amount and environmental impacts of plastic waste across the world. This study was carried out to investigate the density and quality of plastics on the sea surface and seabed of İskenderun Bay. 35 different seabed sampling and 25 different sea surface sampling were conducted by using İskenderun Technical University R/V ISTE-1 vessel. A total of 1 661 581 m2 and 465 511 m2 swept from the seabed and sea surface were scanned, respectively. As a result of these scans, the amount of plastic waste density per unit area of the seabed was found as 0.126 g / m2 ± 0.011 (p: 0.95), and the amount of plastic waste density per unit area of sea surface was calculated as 0.052 gr ± 0.011 (p: 0.95). Scuba dives conducted in river mouths showed plastic deposition pits at the seabed. Major surface current systems and dominant southern winds were found to be effective in the sea surface distribution of plastic materials.
Show more [+] Less [-]Geochemical Indices for the Assessment of Chemical Contamination Elements in Sediments of the Suches River, Peru Full text
2022
Salas-Mercado, Dante | Hermoza-Gutierrez, Marian | Belizario-Quispe, Germán | Chaiña, Fermín | Quispe, Edgar | Salas-Ávila, Dante
The purpose of this study was to evaluate the concentrations of potentially toxic elements in the Suches river using standardized geochemical indices and to identify the main sources of contamination in the section from the Suches lagoon up to 33.8 km downstream of the effluent river, in the district of Cojata, Puno, Peru. The concentration of Al, Ba, Co, Fe, M, Ni, P, V and Zn in sediments of the Suches river was determined by means of mass spectrometry from October 2019 to February 2020. The values of Co, Fe, Mn, Ni, P and Zn exceeded the base values of contamination according to the general geological references while Al, Ba and V, did not surpass them. The contamination factor showed that the elements Co and Ni revealed a very high level of contamination, while the Zn, a considerable level. The area has an average pollution load index value of 2.24, indicating moderate general pollution. The elements Co, Ni, Al and Zn were within the moderate and extreme classification according to the pollution index. The Spearman's correlation analysis allowed determining the association between Al, Fe, Mn, P and V, which share a natural origin and the accumulation of these elements is due to the effects of weathering and soil erosion. The evaluation of the contamination indices and the correlation confirm that Cobalt, Nickel and Zinc are toxic elements associated with gold mining and agricultural activities.
Show more [+] Less [-]Kinetic Characteristics and the Performance of Up-Flow Biological Aerated Filters (UBAF) for Iraqi Municipal Wastewater Full text
2022
Kalash, khairi R. | Al-Furaiji, Mustafa | Ahmed, ِAmer N.
This study utilized kinetic models to study the treatment efficiencies of a laboratory-scale up-flow biological aerated filters reactor (UBAF). The treatment efficiency of a model reactor was studied using different operating conditions of the hydraulic retention times, organic loading rates, and kinetic parameters. As a result of the calculations, the second-order and modified Stover/Kincannon models are appropriate. The substrate removal rate constant K2(S) was 1.7 per day for the reactor, with a correlation coefficient of 0.9979. Utilizing the modified Stover/Kincannon model, the coefficient of the determined concentration was 0.9987; 0.9265; and 0.9685 for Chemical oxygen demand (COD); ammonium nitrogen (NH4+-N); and Total Nitrogen (TN), respectively. The calculation of the saturation value constants and maximum utilization rate for Chemical oxygen demand (COD); ammonium nitrogen (NH4+-N); and Total Nitrogen (TN) was performed using the modified Stover-Kincannon model were 178.57 and 201.80 for COD; 1.876 and 4.6 for NH4 +-N; 3.823 and 6.644 for TN, respectively. It is possible to determine the kinetic parameter for removing COD, NH4+-N, and TN from wastewater by using the modified Stover-Kincannon model.
Show more [+] Less [-]Removal of Colour and COD in Biologically pre-treated Leachate using Activated Carbon from Corn Cobs Full text
2022
Thongkrua, Suchanya | Suriya, Patcharapohn
Activated carbon was prepared from corn cob agricultural waste with different impregnation ratios and pyrolysis times. The optimal adsorbent prepared using at 4:1 ZnCl2:corn cob char ratio at a temperature of 800 °C for 180 min provided the maximum Brunauer-Emmett-Teller (BET) surface area, total pore volume and average pore width, with values of 912.47 m2/g, 0.52 cm3/g and 22.61 Å, respectively. ZnCl2 was effective in creating well-developed pores on the surface of the activated carbon. The removal efficiency and adsorption capacity of the colour and the chemical oxygen demand (COD) of the biologically pre-treated leachate were examined utilizing the best corn cob activated carbon (CCAC) with varying CCAC dosages, contact times and initial pH values. The greatest colour and COD removal effectiveness were 88.6±0.2% and 83.7±0.4%, respectively, at the optimum CCAC dosage of 12 g for 40 min with an initial pH value of 10. In addition, maximum adsorption capacities were achieved for colour and COD of 10.3±0.02 mg/g and 12.6±0.05 mg/g, respectively, under the same conditions. The kinetics of colour and COD adsorption fitted very well with pseudo-second-order kinetic model. The CCAC performs well as an adsorbent for removing colour and COD in biologically pre-treated leachate.
Show more [+] Less [-]Genotoxic Effect, Oxidative Stress and Cell Death due to Metronidazole Application in Gills and Liver Tissues of Rainbow Trout (Oncorhynchus mykiss) Full text
2022
Gürcü, Beyhan | Koca, Serdar | Başimoğlu Koca, Yucel | Çöllü, Fatih | Tuğlu, Mehmet
In this study, the purpose was to investigate the histopathological, genotoxic effect, oxidative stress and cell death due to Metronidazole (MTZ), which is a 5-nitroimidazole compound used widely for the treatment of anaerobic organism infections in fish and humans on gill and liver tissues of Oncorhynchus mykiss.Trout fishes were exposed to 5, 10, and 20 mg/L of MTZ in the aquariums for 2, 4 and 8 days. Staining technics namely H&E, NOS immunohistochemistry, and TUNEL were performed to determine histopathological changes, oxidative damage and apoptosis. Additionally, smear preparations were also prepared from gill blood for genotoxic evaluations. The organ damage started in the 2nd day with 5 mg/L MTZ application and effects increased per duration and dose-dependent manner. It was observed that the gills had the primary and secondary lamellae lengths, with formation of clavate lamellae, fusion in secondary lamellae, separation of epithelium and aneurysm. Regional necrosis, vacuolization of hepatocytes, pycnotic nucleus, enlarged sinusoids were also determined in the liver. NOS immunoreactivity increased with the inducible immunoreactivity (iNOS) that was more prominent when compared to the endothelial immunoreactivity (eNOS). Apoptotic immunoreactivity was higher in the 10 mg 8th day experimental group at liver and gills, and was lower 20 mg 8th day experimental group. When the gills and liver compared with each other, in all doses, immunoreactivity was lower in gills, compared with liver. Genotoxic examinations showed that both number of micronucleated erythrocytes and nuclei abnormalities were higher in MTZ-treated groups.
Show more [+] Less [-]A Review of the Application of Machine Learning and Geospatial Analysis Methods in Air Pollution Prediction Full text
2022
Zhalehdoost, Alireza | Taleai, Mohammad
During the past years, air quality has become an important global issue, due to its impact on people's lives and the environment, and has caused severe problems for humans. As a prevention to effectively control air pollution, forecasting models have been developed as a base for decision-makers and urban managers during the past decades. In general, these methods can be divided into three classes: statistical methods, machine learning methods and hybrid methods. This study's primary intent is to supply an overview of air pollution prediction techniques in urban areas and their advantages and disadvantages. A comparison has also been made between the methods in terms of error assessment and the use of geospatial information systems (GIS). In addition, several approaches were applied to actual data, and the findings were compared to those acquired from previous published literatures. The results showed that forecasting using machine learning and hybrid methods has provided better results. It has also been demonstrated that GIS can improve the results of the forecasting methods.
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