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SICCAINE ELECTROCHEMICAL DETERMINATION ON CoO(OH)-MODIFIED ELECTRODE. A THEORETICAL INSIGHT
2024
Volodymyr Valentynovych | Nazymok, Sílvio C. De Oliveira, Marta V. Kushnir, Yana G. Ivanushko, Yevgenivya V.
In this work, for the first time the theoretical description for siccaine electrochemical determination and electropolymerization over cobalt(III) oxyhydroxide has been evaluated. The electrochemical oxidation includes three scenarios, including hydroquinone to quinone oxidation, triple bond oxidation and electropolymerization, and all of them are included in the mathematical model. The correspondent mathematical model has been developed and analyzed by means of linear stability theory and bifurcation analysis. From the theoretical description it was possible to conclude that siccaine may be efficiently detected by electrochemical way on cobalt(III)-oxyhydroxide modified electrode. Siccaine is also seen as a monomer for the electrochemical modifying polymer film for ROS particle scavenging.
Показать больше [+] Меньше [-]Physicochemical, Heavy Metals and Microbiological Analysis of River and Borehole Water in Ozubulu, Anambra State, South-Eastern Nigeria: Physicochemical, Heavy Metals and Microbiological Analysis of River and Borehole Water in Ozubulu, Anambra State, South-Eastern Nigeria
2024
Onyema, Agu Matthew | Precious, Ijezie Mmesoma | Yakubu, Shedrach | Inya, Agha Inya | Sylvester, Onyima Chibuike
The study aimed to determine heavy metal contamination, and physicochemical and microbial properties of selected river and borehole water in Ozubulu using standard procedures. Results were compared with WHO and NAFDAC drinking water guidelines. Eight samples were collected for analysis using standard analytical methods.The study found that river water samples for R1, R2, R3, and R4 met the World Health Organization's drinking water permissible range in terms of pH, temperature, electrical conductivity, total alkalinity, total acidity, total solids, total hardness, and turbidity. The study found that borehole water had pH, temperature, electrical conductivity, total alkalinity, hardness, turbidity, and total acidity values within a range of 5.20 to 6.60. The heavy metals and trace elements in the river water samples were undetected. The borehole water samples contained various minerals, heavy and trace metals, and total plate, staphylococcus, and coliform counts. The total plate count, total staphylococcus count, and total coliform count were within the range of 3.00 x104-3.00 x106cfu/ml, 1.27 x102-7.73 x102cfu/ml, and 0.39 x102-12.00x102 MPN/ml. This study found no yeast in water samples, and borehole water samples were free from microbial contamination. Results suggest water sources are partially fit for domestic, industrial, and agricultural use.
Показать больше [+] Меньше [-]The Effect of PAC and Alum Coagulants on the Reduction of Organic Matter in River Water during the Coagulation-Flocculation Process (Case Study: 12 Main Rivers during Dry and Rainy Seasons in West Java Province, Indonesia)
2024
lolo, elvis umbu
Natural organic matter (NOM) present in rivers affects the coagulation process in drinking water treatment, specifically coagulation and flocculation processes. Therefore, it is necessary to conduct a laboratory-scale research using jar test. Natural organic matter (NOM) is found in most surface waters in West Java Province, along with suspended particles, colloids, and pathogens. The Jar test apparatus is a laboratory-scale coagulation-flocculation process used to determine the optimal coagulant dosage. Research results indicate that both PAC and alum coagulants affect the coagulation-flocculation process, with PAC exhibits more efficient effect. This advantage can be seen in the floc settling velocity, where PAC flocs settle by 0.80 cm/minute during the rainy season and 0.94 cm/minute during the dry season, while alum coagulant settle by 0.29 cm/minute for both rainy and dry seasons. Another advantage can be observed in the efficiency of NOM reduction. During the rainy season, the NOM reduction efficiency of PAC was 82%, and during the dry season, it was 77%, while alum coagulant reduction efficiency was 74% during the rainy season and 72% during the dry season. The coagulant's response to NOM reduction can also be noticed from the coefficient of determination. The coefficient of determination for PAC coagulant during the rainy and dry seasons were 45.79% and 20.58%, respectively, while alum coagulant values were 32.99% and 19.71% during the rainy and dry seasons, respectively.
Показать больше [+] Меньше [-]Study of the effect of the weather factors on the mechanical properties of the composite material of foam polystyrene and natural wool: Study of the effect of the weather factors on the mechanical properties of the composite material of foam polystyrene and natural wool
2024
montajb
This study investigates the utilization of natural wool as a natural additive to foam styrene, aiming to assess its influence on the mechanical properties of the resulting composite material. Previous research on wool processing was utilized before adding it, our research concluded that 15% wool treaded wool yielded the best rate in terms of water absorption and combustion time. However, it was observed that compression resistance increased with higher additive ratios. The effect of weather factors on the resulting material was investigated by subjecting it to external atmospheric conditions for four months. Repeated tests were conducted to distinguish any variations in the properties of the composite material before and after exposure to these weather factors
Показать больше [+] Меньше [-]Rankala Lake Quarry Water Purification via a Two-Pronged Strategy Involving Hydrodynamic Cavitation and Ozonation
2024
Jadhav, Amarsinh | Gardi, Parvez | Bhosale, Amruta | Kadam, Prajeet | Ghorpade, Dhairyasheel
This research presents a ground-breaking approach to wastewater treatment that leverages hydrodynamic cavitation and ozonation with unprecedented efficiency and environmental benefits by resolving the concern of the ever-present paradox of water scarcity and persistent pollutants in wastewater, and it compels scientists to relentlessly pursue innovative and eco-friendly treatment solutions. This study introduces a pioneering method for treating wastewater that combines hydrodynamic cavitation (HC) and ozonation (O3). This research examined the process of purifying rainwater collected from the Rankala Lake quarry in Kolhapur, India. The treatment, which lasted for approximately 7 hours each day over a span of three weeks, resulted in notable enhancements in water quality. The initial greenish discoloration and bad odor were notably eradicated within a week, without any chemical additives. The microbial burden decreased significantly from 105 CFU/mL to 102 CFU/mL, indicating a strong level of disinfection. The COD decreased significantly from 110 ppm to less than 10 ppm, while the BOD decreased dramatically to undetectable levels (0 ppm) from 55 ppm. In addition, there was a slight change in the concentration of chloride, water hardness, clarity, and total dissolved solids (TDS). This exemplifies the efficacy of the cavitation process coupled with ozonation for converting polluted, discolored, and malodorous water into purified water appropriate for diverse uses.
Показать больше [+] Меньше [-]PIK Determination of Pesticide Residues in cocoyam (Colocasia esculenta) from Selected Local Government Areas of Plateau State, Nigeria: Assessing Pesticide Residues in Cocoyam from Plateau State, Nigeria
2024
Kutshak, Panpe Iliya
This study was conducted to determine the level of pesticide residues in cocoyam (Colocasiaesculenta) from Mangu, Bokkos and BarkinLadi Local Government Areas of Plateau State, Nigeria.Cocoyam and soil samples were collected from two (2) farms each, from the study areas and analyzed for pesticides residues by gas chromatography equipped with electron capture detector.Fourteen (14) different pesticide residues were detected; HCB, p,p’-DDE, Endosulfans, p,p’-DDD, Glyphosphate, Dichlorvos, aldrin, Emamectin, Lindane, t-Nonachlor, 4,4-bypyridinium, Isopropylamine, g-chlordane, heptachlor. The concentrations of pesticide residues are in the range 0.0003-0.3579 mg/kg in cocoyam and 0.0001-1.1377 mg/kg in soil. Cocoyam samples, HCB (0.3579 mg/kg) had the highest concentration while t-nonachlor (0.0003 mg/kg) had the lowest concentration. In the soil samples analyzed, HCB (1.1377 mg/kg) was detected with the highest level while glyphosphate (0.0001 mg/kg) was found to have the lowest level. Cocoyam was found to contained the highest level of residues with HCB (0.3579 mg/kg) in BarkinLadi. Endosulfan, Lindane, t-nonachlor, Aldrin, glyphosphate and g-chlordane showed concentrations below the EU maximum residue limit (MRL), while HCB, p,p’-DDE, p,p’-DDD, Dichlorvos, Emamectin, 4,4-bypyridinium, Isopropylamine, and heptachlor showed concentrations above the EU maximum residue limit (MLR).The continuous consumption of such foods with high pesticide levels can accumulate and could result in detrimental chronic effects in the health of consumers. The statistical analysis showed that there is no significant difference between the individual concentrations and the concentrations at the different sample locations at P≤0.05. | This study was conducted to determine the level of pesticide residues in cocoyam (Colocasiaesculenta) from Mangu, Bokkos and BarkinLadi Local Government Areas of Plateau State, Nigeria.Cocoyam and soil samples were collected from two (2) farms each, from the study areas and analyzed for pesticides residues by gas chromatography equipped with electron capture detector.Fourteen (14) different pesticide residues were detected; HCB, p,p’-DDE, Endosulfans, p,p’-DDD, Glyphosphate, Dichlorvos, aldrin, Emamectin, Lindane, t-Nonachlor, 4,4-bypyridinium, Isopropylamine, g-chlordane, heptachlor. The concentrations of pesticide residues are in the range 0.0003-0.3579 mg/kg in cocoyam and 0.0001-1.1377 mg/kg in soil. Cocoyam samples, HCB (0.3579 mg/kg) had the highest concentration while t-nonachlor (0.0003 mg/kg) had the lowest concentration. In the soil samples analyzed, HCB (1.1377 mg/kg) was detected with the highest level while glyphosphate (0.0001 mg/kg) was found to have the lowest level. Cocoyam was found to contained the highest level of residues with HCB (0.3579 mg/kg) in BarkinLadi. Endosulfan, Lindane, t-nonachlor, Aldrin, glyphosphate and g-chlordane showed concentrations below the EU maximum residue limit (MRL), while HCB, p,p’-DDE, p,p’-DDD, Dichlorvos, Emamectin, 4,4-bypyridinium, Isopropylamine, and heptachlor showed concentrations above the EU maximum residue limit (MLR).The continuous consumption of such foods with high pesticide levels can accumulate and could result in detrimental chronic effects in the health of consumers. The statistical analysis showed that there is no significant difference between the individual concentrations and the concentrations at the different sample locations at P≤0.05.
Показать больше [+] Меньше [-]THE THEORETICAL DESCRIPTION FOR THE ELECTROCHEMICAL PYROGALLOL AND HYDROXYQUINOL ELECTROCHEMICAL DETERMINATION OVER CoO(OH)-MODIFIED ELECTRODE
2024
Tkach, Volodymyr Valentynovych
The theoretical description for hydroxyquinol and pyrogallol electrochemical determination in food and wastewater has been made in this work. The efficiency of the cobalt (III) oxyhydroxide for this determination is verified from either electroanalytical and electrosynthetical point of view, as it also provides the assisted electro(co)polymerization. The stable steady-state is easy to obtain and maintain, which confirms the efficiency of the electrode modifier and the easy interpretation of analytical signal.
Показать больше [+] Меньше [-]THE THEORETICAL ASPECTS OF THE ELECTROSYNTHESIS AND ELECTROPOLYMERIZATION OF SOME NAPHTHOQUINONIC DERIVATIVES IN NEUTRAL AND ACIDIC MEDIA
2024
Tkach, Volodymyr Valentynovych
For the first time, the possibility of the electrochemical synthesis and polymerization of some novel modified naphthoquinonic compounds has been described. The correspondent mathematical model has been analyzed by means of linear stability theory and bifurcation analysis. It has been shown that the electroorganic synthesis may serve as an interesting substitution for Suzuki reaction for the synthesis of ferrocenyl naphthoquinone and its polymer. The oscillatory and monotonic instability in this case will be more probable than in the general electropolymerization case.
Показать больше [+] Меньше [-]Machine Learning in Chemical Kinetics: Predictions, Mechanistic Analysis, and Reaction Optimization.
2024
Samuel, H.S. | Etim, Emmanuel E. | Nweke-Maraizu, Ugo | Yakubu, Shedrach
Chemical kinetics is a core area of physical chemistry that examines the speeds of chemical processes and the mechanisms that underlie them. Machine learning (ML) techniques have become effective tools for improving understanding and prediction in this area. The use of machine learning in chemical kinetics research is examined in this abstract, with particular emphasis on how it can be used to forecast A deeper knowledge of reaction kinetics is made possible by the capability of machine learning (ML) to handle high-dimensional data and learn from many chemical systems. This opens up significant opportunities for developing new chemical processes, improving catalysis, and hastening the discovery of new materials.
Показать больше [+] Меньше [-]CHARACTERIZATION AND PLIMINARY DESIGN OF A TANNERY WASTEWATER TREATMENT PLANT
2024
Adamu Dandajeh, Aliyu | Zainab Uyoh Abdullahi | Aliyu Ishaq | Abdullahi Umar
The tannery industry produces pollutants that possess physical, chemical, and biological characteristics, necessitating their characterization and treatment before being discharged into receiving streams. Effluent samples were sourced from the Nigeria Institute of Leather Science and Technology in Zaria, Nigeria, and the physico-chemical parameters were examined on a weekly basis for a duration of 7 weeks. The findings demonstrate pH values ranging from 7.64 to 10.45, while the temperature ranged from 22 to 28 oC. In addition, the alkalinity levels were found to range from 1900 to 5200 mg/l, acidity (900 to 6800 mg/l), BOD (120 to 600 mg/l), and total solids (390 to 9850 mg/l). Moreover, the dissolved solids were discovered to range from 210 to 6650 mg/l, suspended solids (172 to 2470 mg/l), chloride (250 to 2399 mg/l), phosphate (1.2 to 3.6 mg/l), nitrate (0.0 to 2.4 mg/l), cadmium (0.001 to 0.008 mg/l), chromium (0.788 to 1.665 mg/l), and lead (0.018 to 0.049 mg/l). On this note, a preliminary design for waste treatment reveal that 1 anaerobic pond (10.2 m length, 3.4 m breadth, and 3.0 m depth), 2 facultative ponds (21.45 m length, 7.15 m breadth and 1.5 m depth), and 1 maturation pond (16.89 m length, 5.63 m breadth, and 1.5 m depth) are required for effluent treatment with a land area of 435.92 m2. These results indicate that the effluents fail to meet the standards for discharge into surface water and land application. Keywords: characterization, effluent, pollutants, tannery industry, treatment
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