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Complex application of microbiological characteristics in bottom sediments and biochemical parameters of mussel Mytilus galloprovincialis (Lam.) for assessing the ecological state of marine coastal areas Full text
2022
Skuratovskaya, Ekaterina | Doroshenko, Yuliya
Comparative analysis of microbiological indicators (heterotrophic and hydrocarbon-oxidizing bacteria) in bottom sediments and biochemical parameters (level of oxidized proteins (OP) and lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities) in hepatopancreas of mussel Mytilus galloprovincialis (Lam.) from three Sevastopol bays - Laspi, Kazach’ya, Streletskaya (the Black Sea) was carried out. The results obtained allowed to identify certain differences between the studied areas and characterize their ecological state. The maximum abundance of heterotrophic and hydrocarbon-oxidizing bacteria was found in the most polluted Streletskaya Bay (95,000 and 250 cells/g respectively), the minimum - in the conventionally pure Laspi Bay (2,500 and 1.5 cells/g respectively). Parameters of prooxidant-antioxidant system (level of OP and LPO, SOD and CAT activities), as well as ALT activity in the hepatopancreas of mussels from Streletskaya Bay were found higher as compared to those in other tested areas. Most significant differences (more than twofold) in SOD activity, LPO content and basic ketone forms of OP levels were found between Laspi and Streletskaya bays. The results obtained indicate the severe pollution and less favorable living conditions for aquatic organisms in Streletskaya Bay, as well as demonstrate the high level of biochemical adaptation of mussels to complex environmental pollution. The studied parameters can be applied in the ecological monitoring of the coastal sea water areas.
Show more [+] Less [-]Studying the photostabilization activity of Poly(Vinyl Chloride) films containing 4-amino-5-(((5-methyl-1H-benzo[d]imidazol-2-yl)thio)methyl)-2,4-dihydro-3H-1,2,4-triazole-3-thiol with a dibutyltin complex Full text
2022
Mahmood, Zinah | Alias, Mahasin | Kadhom, Mohammed | Bakir, Shaimaa | Yusop, Rahimi | Husain, Amani | Yousif, Emad
A new traiazole derivative (4-amino-5-(((5-methyl-1H-benzo[d]imidazol-2-yl)thio)methyl)-2,4-dihydro-3H-1,2,4-triazole-3-thiol, (L), was employed as a chelating ligand to form a dibutyltin chloride complex and improve the poly(vinyl chloride) (PVC) properties. The doped PVC films were characterized via FT-IR, UV-Vis spectrum, elemental analyses (C, H, N, and M (metallic)), and magnetic susceptibility and conductivity measurements. These characterizations were conducted at room temperature, and it was disclosed that the chelating ligand rules as a bidentate chelate. The photostabilization examination of plain and L-doped PVC films was conducted in the presence of ambient air using the accelerating weather tester, where the doping ratio was fixed to 0.5 wt.%. The photostabilization performance of the additive was evaluated by tracking the indexes of carbonyl (ICO), polyene (IPO), and hydroxyl (IOH), and weight loss relationship with irradiation time. It was noticed that the values of ICO, Ipo, and IOH enhanced with the irradiation time, where this improvement relied on the presence of the Bu2SnL complex.
Show more [+] Less [-]Application of Ceramic Filter and Reverse Osmosis Membrane for Produced Water Treatment Full text
2022
Putri, Rara | Nasir, Subriyer | Hadiah, Fitri
The effect of ceramic filter composition on improving the quality of produced water by reducing total dissolved solids (TDS), barium, and phenol for reverse osmosis (RO) treatment was investigated in the present work. The ceramic filters were fabricated using a residue catalytic cracking (RCC) unit spent catalyst with and without activation, clay, and Dioscorea hispida starch (DHS), at various compositions. The result showed that the optimum removal of TDS, barium, and phenol in produced water was achieved at a flow rate of sample 7 L/min and an operating time of 90 min. Ceramic filter with the composition of 60% spent catalyst without activation: 37.5% clay: 2.5% DHS reduced 34.84% TDS, 27.97% barium, and 71.11% phenol. While, the ceramic filter with a composition of 37.5% activated spent catalyst: 60% clay: 2.5% DHS was removed 51.44% TDS, 27.93% barium, and 85.29% phenol from produced water. The next steps of treatment of filtrates of the ceramic filter using reverse osmosis (RO) membrane showed that the permeate met the Indonesian standard for oil and gas wastewater. In addition, adsorption of TDS, barium, and phenol from produced water was dominated by clay composition in the ceramic filter.
Show more [+] Less [-]Arsenic Bioremediation Potential of Arsenite Oxidizing Bacteria Isolated from Geogenic and Anthropogenically Contaminated Soil Full text
2022
Mobar, Sanjoli | Bhatnagar, Pradeep
The soil of many places of eastern India contains high amount of arsenic, due to several geogenic activities in this area. In the specific regions of the country where there is no such type of Geogenic activities, the soil is found to be almost free of arsenic. In such places where there are industries, the soil is being contaminated with the arsenic due to anthropogenic activities. One of such site which was selected for the study was in close vicinity to the textile industries in Jaipur, Rajasthan, India discharging their effluents having 423 µg/g arsenic. While the soil sample collected from the far eastern part of Tezpur Assam, India, contaminated by Geogenic sources contained 443µg/g arsenic. Four arsenite resistant bacterial strains were isolated from each of the samples. Strains SE-3 and TB-1 isolated from Jaipur and Tezpur, respectively showed highest minimum inhibitory concentration of 46.5mM and 38.7mM sodium arsenite. Based on 16S rDNA sequencing and nucleotide homology and Phylogenetics analysis strain, SE-3 was identified as Pseudomonas sp. SE-3 (accession no. KP730605) and TB-1 as Bacterium TB-1 (accession no KP866680). Complete oxidation of arsenite to less toxic form arsenate was observed in Pseudomonas sp. SE-3, while 64.6% by Bacterium TB-1. The arsenite oxidation was supported on the molecular level by confirming the presence of aox gene by PCR amplification. The enzyme activity of arsenite oxidase was also established. Arsenic hyper tolerant bacteria isolated from these soils having arsenite oxidizing ability show a promising way for the bioremediation of arsenic in contaminated soil.
Show more [+] Less [-]Assessment of Microplastics Distribution and Related Water Quality in an Urban Canal, Thailand Full text
2022
Eamrat, Rawintra | Taweesan, Achara | Pussayanavin, Tatchai
Microplastics pollution has become a matter of global concern because of its effects on aquatic life and the ecosystem. This study investigated the abundance and types of microplastics found in an urban canal of Thailand. Water quality and the relationship between microplastics pollutants and the physicochemical properties of water quality were also analyzed to provide evidence for this study. The mean abundance of microplastics was 370 ± 140 particle(p)/m3. The highest number and concentration of microplastics were found on surface water corelated with urbanization. Transparent brown and transparent colors in the form of film and fiber/lines were the predominant morphology. Polypropylene (PP) and polyethylene (PE) were the most abundant polymer type in all surface water samples. Furthermore, water quality was related with microplastic pollution. The physicochemical properties of turbidity (0.99), conductivity (0.97), total solid (0.95) and biological oxygen demand (0.84) were accounted for greatest influences on microplastics distribution. The estimated equation of microplastics was also closely corelated with water quality. These results demonstrate that microplastic pollution has progressed more in poor water quality than good water quality, indicating that the inflow process and sources of microplastics are similar to those of other pollutants. Therefore, this study is expected to encourage and enforce solid waste and wastewater management policies that prevent microplastics pollution in the environment.
Show more [+] Less [-]Kinetic and Thermodynamic Parameters of Cadmium Ion Removal by using the Orange Wood-Synthesized Activated Carbon Nanoparticles Modified with Cysteine Full text
2022
Rostami, Elham | Esfandiari, Nadia | Honarvar, Bizhan | Nabipour, Moein | Arab Aboosadi, Zahra
Activated carbon is known an as appropriate adsorbent due to its high adsorption capacity for most pollutants, especially heavy metals. In the present study, activated carbon was synthesized from orange wood by employing the chemical activation method. Additionally, cysteine amino acid was used to modify the activated carbon surface, leading to an enhancement in adsorption ability because of having a nitrogen group. Based on the results, the adsorption capacity of the modified activated carbon was obtained at 120 mg g-1 adsorbent. The parameters affecting adsorption such as the amount of used adsorbent, as well as solution pH, primary concentration, and contact time were optimized, followed by performing the adsorption process under optimal conditions. The optimal adsorption conditions included the pH of 6, contact time of 60 min, adsorbent amount of 50 mg, and primary cadmium concentration of 80 ppm. Further, kinetic and thermodynamic parameters were assessed and optimized. The results of which represented the best fit between adsorption with Langmuir isotherm and the pseudo-second-order kinetic model. The results represented that the quasi-second-order model with a higher regression coefficient (R2 = 0.97) described the experimental data better than the quasi-first-order one (R2 = 0.83). The adherence of adsorption kinetics to the pseudo-second-order model suggested a chemical interaction as the rate-determining step. Regarding adsorption thermodynamics, the effect of temperature was examined on adsorption by using Van't Hoff's equations, which reflect the endothermicity of the process.
Show more [+] Less [-]Relationships between Ambient Air Pollution, Meteorological Parameters and Respiratory Mortality in Mashhad, Iran: a Time Series Analysis Full text
2022
Mohammadi, Mitra | Hatami, Morteza | Esmaeli, Reza | Gohari, Samaneh | Mohammadi, Mandana | khayami, Elahe
The time series model has been exploited to estimate the relationship between meteorological variables and air in Mashhad with respiratory mortality. For this purpose, data on respiratory mortality was based on data recorded on March 2014 to 2015. In order to investigate the effect of meteorological variables and air pollution values on respiratory mortality, the Box- Jenkins time series model has been utilized. Moreover, the effect of age and seasons on the number of respiratory deaths was assessed by the linear regression and ANOVA test. The fit of the final model to determining the monthly relationship between meteorological variables and air pollutants with the number of respiratory mortalities is a (1,0,2) ARIMA. In the monthly survey, temperature and rainfall have the inverse relationship and pressure has the direct relationship with the average of 7.4, 3.2, and 17.42 on the respiratory mortality. It was also found direct relationship between the mortality from respiratory diseases and CO and O3 and inverse relationship with SO2, NO2 and PM2.5 pollutants with an average of 67.40, 17.42, 17.89, 6.83, and 0.68, respectively. Also, the results of this study indicate that older people are more likely to be affected by the inappropriate status of air quality by 0.37%. The results showed a significant difference between respiratory mortality in different seasons of the year, and the highest number of deaths occurred in the winter.
Show more [+] Less [-]Brick Kilns Air Pollution and its Impact on the Peshawar City Full text
2022
Hussain, Amjad | Khan, Naseer | Ullah, Munzer | Imran, Muhammad | Ibrahim, Muhammad | Hussain, Javid | Ullah, Hussain | Ullah, Irfan | Ahmad, Ikram | Khan, Muhammad | Ali, Meher | Attique, Faisal
In recent times, the brick kiln contributes to air pollution is one of the most emerging issues worldwide. In this research work, the Peshawar city, ambient air quality was measured, using a fixed air monitoring station to evaluate the impact of gaseous emission from brick kilns on ground level. In this study, the portable gas analyzer (PG-250) was used to quantify brick-based emitting carbon monoxide (CO), sulfur dioxide (SO2) and nitrogen oxide (NOx) from 3 brick kilns in the city of Peshawar. It was noticed that the average concentration of SO2 and NOx exceeds the National Environmental Quality Standards (NEQS) of Pakistan specifically, in terms of air quality. The brick kilns in District Peshawar have shown negative effects on the environment. It is necessary to take various measures to monitor the brick kiln embosom regularly before it becomes a significant risk for individuals. In conclusion, the impact of air pollution on physical activity and sedentary behavior at a specific time may be different.
Show more [+] Less [-]Investigating the Potential Response of Jute Varieties for Phytoremediation of Arsenic Contaminated Soil Full text
2022
Nahar, Nazneen | Gani, Md Nasimul | Huq, SM Imamul
A pot experiment was carried out in the green house of Bangladesh Jute Research Institute (BJRI), Dhaka to study the response of jute (Corchorus capsularies and Corchorus olitorius) to the accumulation of As from soil to plants when various rates of As were applied. In the experiment, four treatments of arsenic (control, 10, 20 and 40 mg/kg) were applied. The salt sodium meta-arsenite (NaAsO2) was used as a source of As. Three jute varieties of CVL-1, 0-9897 and OM-1 were used. CVL-1 variety is As sensitive whereas the 0-9897 and OM-1 varieties appeared to be As tolerant and OM-1 takes up the highest amount of As. Arsenic will be ingested into the body exceeding the maximum allowable daily limit (0.22mg/kg per day) through the consumption of 100g of jute leaves of these three varieties per day. Accumulation of As at 10 and 40 mg/kg treatment, the maximum was observed at 52 days harvest for CVL-1 while for the other two treatments, the maximum was observed at 42 days of growth. In the case of 0-9897 and OM-1 varieties, overall the maximum accumulation of As was observed at 42 days of growth at 40 mg/kg treatment.
Show more [+] Less [-]Polystyrene and Polymethylmethacrylate Microplastics Embedded in Fat, Oil, and Grease (FOG) Deposits of Sewers Full text
2022
Nikpay, Mitra
Fat, oil, and grease (FOG) deposits in the urban sewer system affect the optimal performance of the wastewater collection system and treatment plant, while increasing sewer maintenance costs. The interaction of microplastics (MPs) and FOG in the sewer system could drastically change the quality of deposited materials and the fate of MPs in raw sewage. In this study, the batch experiment was conducted to explain the mechanism of FOG formation by synthetic wastewater and its interaction with polystyrene (PS) and polymethyl methacrylate (PMMA) particles. We found three different segments for FOG deposits in the batch, namely static and buoyant micro-deposits, gel-like, and solid deposits. The average size of micro-deposits adhered to the solid-liquid interface of the container was 25 µm and buoyant deposits with a small size of 3 µm adsorbed onto the MPs at the liquid-air interface. The gel-like formation promoted a virtual liquid phase where PS and PMMA were confined and segregated. Some PMMA particles were entrapped in the self-assembly of biopolymers that formed between the PS particles. This research indicates that FOG deposition in the urban sewers contains high numbers of MPs, such that any plan involving a reuse or disposal program requires a risk assessment.
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