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Microplastics on Silkworms (Tubifex Spp) in the Brantas River, Indonesia
2024
Eri Wardoyo, Iva Rustanti | Yunior, Yudha | Marlik, Marlik | Kriswandana, Ferry | Nurmayanti, Demes | Khambali, Khambali
Microplastics can contaminate water owing to their small size. If aquatic biota consume microplastics, they disrupt their reproductive processes, digestive tracts, and development. This study aimed to identify microplastic waste from silkworms (Tubifex spp.) in the Brantas River. The study was conducted in a descriptive manner by collecting samples of microplastic waste from silkworms and examining the shape, type, amount, and percentage of microplastic abundance in the river. An FTIR test was used to determine the microplastic content. Using a Zeiss Axio Zoom.V16 at 50x magnification, microplastic particles from individual worms and worm samples were visually identified. Then, the 50% hot needle test was used to determine the composition of the plastic. A total of 263 microplastic particles were found in the worm samples. Silkworms (Tubifex spp.) in the Brantas River, Kediri City, were shown to contain four types of microplastics, namely fibers, filaments, fragments, and granules, which were dominated by filament particles with 49% filament content, 45% fiber, 5% fragments, and 1% granules. The microplastic polymers identified via FTIR were polyethylene and ethylene-polypropylene-diene copolymers. These microplastics can originate from plastic bags, used drinking bottles, rope fibers, and pieces of water hose, which are often found around the Brantas River. Silkworms found in the Brantas River contain microplastic waste from various pollution sources.
Mostrar más [+] Menos [-]Role of Methanotrophs in Methane Oxidation from Municipal Solid Waste Dumpsites in Tropical Countries
2024
Srivastava, Tanmay | Srivastava, Vartika | Manukonda, Suresh Kumar
Municipal Solid Waste (MSW) dumpsites are one of the major source of methane (CH4) emissions due anaerobic degradation of organic matter content in the waste. Control technologies are available to reduce these emissions, but they are costly and their application on existing sites is complex. Moreover, tropical climate is responsible for rapid degradation of organic matter in open dumps leading to substantial CH4 emissions mainly due to hot and humid conditions amongst other factors. Methanotrophs are bacteria capable of oxidizing CH4 into carbon dioxide (CO2) by virtue of methane monooxygenase enzyme. Various cover materials can be utilized to enhance methane oxidation (MO) ability of these organisms by providing favorable conditions thus converting methane from unmanaged dumpsites into CO2 which has lower global warming potential. Hence their application shows great potential for contributing towards meeting the greenhouse gas (GHG) reduction goals. This review focuses on the attempts to attenuate CH4 emissions by different biocover systems and the current scenario while giving special emphasis to tropical conditions.
Mostrar más [+] Menos [-]The Influence of Outdoor Exposure Concentrations on Indoor Air Quality in Rudimentary Designed Household Structures: Mpumalanga Province, South Africa
2024
Madonsela, Benett Siyabonga | Maphanga, Thabang | Malakane, Karabo Concelia | Phungela, Terry Takalani | Gqomfa, Babalwa | Grangxabe, Sinalo | Thamaga, Humphrey Kgabo | Hajji, Lhoussain | Lekata, Stanley | Karmaoui, Ahmed | Mbonane, Thokozani Patrick
There is a belief that ambient air pollution is accountable for degrading the air quality indoors. Although in principle the indoor air quality should be better than that of outdoor air quality given the shielding effect of a house structure. However, ambient air quality can infiltrate and influence indoor air pollution concentrations in low-income urban informal settlements due to rudimentary designed household structures. Given this phenomenon, the current study endeavoured to explore the influence of outdoor exposure concentration on indoor air quality within the informal settlements of urban neighbourhoods. The exposure concentrations of indoor and outdoor particulate matter and nitrogen dioxide pollutants were simultaneously measured during summer and winter seasons. The GilAir Plus air sample pump was used to acquire measurements of particulate matter collected over 48 hours. While nitrogen dioxide gases were measured using passive diffusive samplers. All statistical analyses were performed using Python (version 3.8) Spyder. The current study has discovered that in many instances the results were comparable indoors and outdoors. For instance, this has been corroborated by the nitrogen dioxide discoveries where the current results were slightly comparable as indoor exposure concentrations values were recorded to be between (4 µg/m3 and 13 µg/m3), whilst the outdoor concentration ranged between (6 µg/m3 and 11 µg/m3). Likewise, a similar trend was observed for particulate matter exposure concentrations indoors (14 µg/m3 ) and (12 µg/m3) outdoors. The statistical inferences futher confirmed that the exposure values of indoor and outdoor were not significant (p>0.05) within the study areas of concern.
Mostrar más [+] Menos [-]Mechanisms of Trace Metal Elements Removal from Water using Low-Cost Biochar Adsorbents: A mini review
2024
Srivastav, Arun Lal | Rani, Lata | Sharda, Prakriti | Sharma, Ajay
Trace metal elements are toxic to the environment and human health and can be removed from water through adsorption. Development of low-cost adsorbents would always been a matter of achievement of every adsorption study as usually many adsorbents were found to be expensive in nature. In this regard, biochar adsorbents gained significant attention due to high adsorption capacity, low-cost and environmental sustainability. Pyrolysis is used to produce biochar adsorbents at varying temperature ranged from 300°C-700°C. The adsorption capacities of palm fiber biochar adsorbents are remarkable which was found around ~198 mg/g for cadmium removal. However, bamboo-based biochar had 868 mg/g of adsorption capacity for arsenate removal. This review aims to provide the current discusses the sources and impacts of trace metal elements in water along with properties of biochar including its composition, surface area, pore structure, and surface functional groups. Further, various types of biomasses have also been mentioned for producing biochar such as agricultural wastes, food wastes, forestry residues, etc. The paper also discusses the different types of mechanisms involved in the adsorption of heavy metal biochar adsorbents like electrostatic attraction, ion exchange, surface complexation etc.
Mostrar más [+] Menos [-]Application of Artificial Neural Network and Multiple Linear Regression for Modelling Adsorptive Removal of Pb (II) ions over Cedrus deodara Bark Powder
2024
Lall, Anurag | Pandey, Avinash | Mani, Jyoti
Cedrus deodara is a coniferous tree native to Himalayan region. Its wood is a valuable resource for the timber industry; however, its bark is typically discarded as a waste material. The present study examines the performance of Cedrus deodara bark powder (CD) as an inexpensive adsorbent for elimination of Pb (II) ions. In addition to this multiple linear regression (MLR) and artificial neural network (ANN) models were developed for modelling the adsorption process and prediction of Pb (II) removal efficiency. The structural and chemical properties of CD were explored using Field Emission Scanning Electron Microscope (FE-SEM), Energy Dispersive Spectrometer (EDS), X-Ray Diffractometer (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). Batch experiments were conducted to investigate the influence of factors including pH, contact time, initial Pb (II) concentration and temperature on Pb (II) adsorption. The adsorption followed pseudo-second-order kinetic and Langmuir isotherm models with maximum monolayer uptake capacity 77.52 mg/g. Based on the thermodynamic criteria, the process was endothermic and spontaneous with enthalpy change (ΔH = 8.08 kJ/mol), free energy change (ΔG = -2.44 kJ/mol) and entropy change (ΔS = 0.03 kJ/K/mol). Statistical comparison of MLR model (R2 = 0.817, RMSE = 8.954, MAPE = 17.379 %) and ANN model (R2 = 0.993, RMSE = 1.777, MAPE = 2.054 %) confirmed that ANN model was far more accurate in predicting removal efficiency.
Mostrar más [+] Menos [-]Biomonitoring of Heavy Metals Accumulation with Pseudevernia furfuracea (L.) Zopf in Kırşehir Province, Türkiye
2024
Işık, Volkan | Yıldız, Atila
Today, the problem of air pollution has been highlighted by rapid population growth and urbanisation, along with the development of industry. Over the last fifty years, much attention has been paid to the relationship between lichens and airborne particulate matter (especially heavy metals). The use of living organisms in air pollution studies is now widely accepted in many countries and the results of these biomonitoring studies are very important for future action. The goal of this study was to determine heavy metals in Kırşehir province using the bag technique, a biomonitoring approach, with Pseudevernia furfuracea (L.) Zopf lichen and to develop a pollution map of the city. In November 2002, lichen specimens were obtained from an unpolluted region in the Yapraklı Mountains, Çankırı, and transplanted to 4 distinct places in Kırşehir. After 3 and 6 months of exposure, they were collected in order to analyse heavy metals (Cu, Cd, Mn, Ni, Pb and Zn) with Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). In addition, chlorophyll-a and chlorophyll-b contents were determined by Dimethyl sulfoxide (DMSO) method. The findings revealed that the heavy metal contents in various stations are the result of industrial, traffic, and heating activities. As a result, P. furfuracea showed excellent bioindicator ability for detecting air pollution.
Mostrar más [+] Menos [-]The Protective Role of Date Seeds Extract on the Reproductive System of Male Chickens Exposed to Gamma Radiation
2024
Khattab. AL-Dulamey, Qusay | Abed. Al-Jawwady, Yasir | Hasan, Mowafak | Ahmed Najim, Laith
The purpose of this investigation is to determine how gamma radiation-induced oxidative stress impacts the reproductive system of adult chickens. In this study, we used 39-57 weeks old cocks’ chickens to assess the significance of semen volume10-3liter per bird per ejaculation). Sperm count overall (108 cells per ejaculation) and count per milliliter (108 cells). The volume, concentration data, and sum sperm data of cock chickens all increased significantly with age, though not at all ages; rather, just at a select few ages that were considered to be the control (regulate) group. These data were found after 35 days of gamma radiation at soft dose rates (soft intensity) of at100, 120 and 130cm between cages of chickens and radioactive source with 0.402, 0.279 and 0.237 Gy/h respectively. This is a six-hour daily chronic dose rate (extended duration of radiation). As the soft dosage rate was gradually increased, a significant decline in the values was observed. The semen volume data drop ratio was calculated for each male chicken generation and compared to the control group using three chronic moderate doses of irradiation at doses ranging from around 4.8 to 13.6 percent and semen concentrations from roughly 4.9 to 14 percent. The average results from both groups showed that when the intensity of the gamma ray radiation increased, all metrics significantly declined. Using date seeds extract(Phoenix dactylifera L.) as a defense against oxidative stresses brought on by radiation exposure and to lower its percentage data, especially on particular sperm data qualitiesDue to its availability in the Middle East, the use of date seeds extracts(Phoenix dactylifera L.) in this study proved beneficial in terms of both economic return and fertility-boosting effects on chickens, as evidenced by the positive results obtained when compared to other antioxidants under the same conditions. Due to its availability in the Middle East, the use of date seeds extracts(Phoenix dactylifera L.) in this study proved beneficial in terms of both economic return and fertility-boosting effects on chickens, as evidenced by the positive results obtained when compared to other antioxidants under the same conditions.
Mostrar más [+] Menos [-]Impact of Fertilizer Factory Emissions on Radiological Content of Soil: A Study in Upper Egypt
2024
Fares, Soad
This study investigated the potential impact of a fertilizer factory in Upper Egypt on the surrounding soil's radioactivity levels. Gamma-ray spectrometry was used to measure the concentrations of naturally occurring radionuclides (226Ra, 232Th, and 40K) in soil samples collected near the factory. Additionally, radon gas concentrations were measured, and various radiological hazard indices were calculated. Activity concentrations of 238U, 226Ra, 232Th, and 40K varied in the soil samples, ranging from 110.63 to 326.12 Bq/kg for 238U, 172.72 to 582.37 Bq/kg for 226Ra, 25.63 to 189.15 Bq/kg for 232Th, and 252.20 to 713.24 Bq/kg for 40K. Radium equivalent activity, absorbed gamma dose, and external and internal hazard indices exceeded permissible levels. Radon gas concentrations varied from 20.89 to 192.30 Bq/m3, with an average of 104.43 Bq/m3. The calculated effective dose from radon inhalation exceeded the recommended limit. The elevated levels of radioactivity in soil and the high radon gas concentrations suggest a potential health risk for farmers and residents near the fertilizer factory. Further investigations and mitigation strategies may be necessary to ensure the safety of the surrounding population.
Mostrar más [+] Menos [-]Electro Oxidation Process for Wastewater Treatment in Petroleum Refineries
2024
Habl, Ali | Amoeey, Ali | Mustafa, Malik | Alalwan, Hayder
In this research, successive electro-oxidation (EO) process was utilized to eliminate some of the primary organic contaminants in effluent wastewater, specifically phenol and chemical oxygen demand (COD). The performance of the electro-oxidation (EO) process was studied by using two graphite electrodes as anodes and three stainless steel electrodes as cathodes, which is a new strategy in this field. Taguchi method has been used to design experiments to approach the best experimental conditions for phenol and COD removal as significant responses. The best operating conditions that resulted in the maximum reduction of phenol and COD were current density (CD = 25 mA/cm2), pH = 4, support electrolyte (NaCl=2g/l), the distance between electrodes (Dist.=5mm), and time of 60 minutes. At these operating conditions, phenol and COD removal were 99.27% and 99.96%, respectively. This work provides important insights into a novel water and wastewater treatment method with a detailed analysis of the results.
Mostrar más [+] Menos [-]A framework of Trapezoidal Fuzzy Best-Worst Method in Location Selection for Surface Water Treatment Plant
2024
Debnath, Kalyani | Debnath, Piyali | Choudhury, Sudipa | Saha, Apu | Majumdar, Abhijit
Decision-making under uncertainty refers to a dilemma when a decision-maker is aware of a variety of potential natural states but lacks adequate information to assign any probabilities of occurrence to them. The uncertainty related to the input parameters is one of the main issues in the majority of decision-making situations. Uncertainty may produce some irrational results, which could make the decision-making process even more challenging. To overcome this challenge, a fuzzy extension of Best-Worst Method (BWM) has been proposed, using trapezoidal fuzzy sets, to combine the advantages of a reduced number of pair-wise comparisons and easy handling of ambiguity. The criteria and alternatives have been evaluated by the proposed Trapezoidal Fuzzy Best-Worst Method (TrFBWM), where the weight of each element is represented by a Trapezoidal Fuzzy Number (TrFN). To verify the coherence of judgment, the consistency ratio is evaluated for TrFBWM. The proposed method is then applied to the location selection of a water treatment plant along the bank of the Brahmaputra river in Assam. The obtained results are compared to one previous work and found that the outcomes of the proposed method indicate a good agreement with that. The outcomes of the study provide useful insights for selecting a suitable location for a surface water treatment plant which can also be extended to other service facilities.
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