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Simulating of Clogging Process in the Leachate Collection System in the Municipal Solid Waste Landfill using Column Experiments Texto completo
2023
Golhosseini, Zeynab | Jalili Ghazizade, Mahdi | Safari, Edwin
Clogging of the drainage layer is the main reason for the inefficiency and failure of the leachate collection system in municipal solid waste (MSW) landfills. One of the most important challenges in the design and operation of landfills is to identify the factors affecting the drainage layer clogging and the extent of their influence especially in the real scale. In this study, five experimental columns were designed to investigate the effective factors on the clogging of the drainage system in the MSW landfills, making it possible to measure the effect of different parameters on the drainage layer clogging through simulating the real conditions. The designed columns are capable to apply the boundary conditions of the MSW landfill including temperature, pressure, and leachate recirculation as well as measuring the permeability of drainage layer. High strength real leachate recirculated in the experimental columns to monitor the degree of drainage layer clogging through the regular measurement of permeability in the different columns. The results showed hydraulic conductivity of the drainage layer decreased between 20 to 50 percent in different samples over time. Although the particle size of drainage materials directly influences the reduction of hydraulic conductivity, the common concentration of calcium carbonate in the materials of the drainage layer does not considerably affect this issue. Formation of biofilm in the drainage layer was observed through scanning electron microscope (SEM) and visual inspection in all columns indicating the proper performance of clogging process simulator which is designed and developed in this research.
Mostrar más [+] Menos [-]Application of Electrostatic Precipitator with Electrode Distance Variation in Reducing Dust Levels in The Manufacturing Industry Texto completo
2023
Pujiono, Pujiono | Budi Prijanto, Teguh | Nurhayati, Ati | Aripin, Salma
A potential hazard is anything that could potentially cause damage, accident, injury, loss, or even death due to the system or work processes. Hazards in the work environment are due to physical, biological, chemical, and psychosocial factors. One of the chemical factors hazards in the work environment that require control is the level of dust in the air environment at work. High levels of dust can cause health problems for workers. These health problems can cause dust allergies, impaired lung function, and other lung function disorders due to the dust that can eventually reduce worker productivity. Out of all industries, the manufacturing industries are usually high in dust content. During the manufacturing process, it is crucial to maintain efforts in controlling risk factors. This research aims to develop a tool that can reduce the air dust level in the industrial environment. Therefore, this study tries to apply an electrostatic precipitator with electrode distance variations to reduce dust levels in the manufacturing industry. The results of this study are the dust content reduction percentage, an electrode distance of 4 cm resulted in 52.3% to 64.9%, electrode distance of 6 cm is 35.5% to 46.7%, while an electrode distance of 8 cm is 16.6% to 26.7%. There is a difference in the electrodes effect of 4 cm, 6 cm, and 8 cm with a decrease in dust levels in the air. The most effective electrode distance in decreasing the air dust level is a 4 cm distance.
Mostrar más [+] Menos [-]Assessing the Effect of Environmental Stressors on the Community Structure of Macroinvertebrates and Water Quality of River Ugbalo, Nigeria Texto completo
2023
Olusegun Olatunji, Emmanuel | Abubokhai Elakhame, Luckey | Catherine Osimen, Ekikhalo | Ovie Edegbene, Augustine
Aquatic macroinvertebrates play significant roles in the benthic zone of the aquatic ecosystem and they have different tolerance level to pollution. Globally, macroinvertebrates are usedas bioindicators in determining the ecological health and water quality status of aquatic ecosystem. Therefore, this study focused on the community structure of benthic macroinvertebrates in River Ugbalo, south-south Nigeria. Macroinvertebrates and physicochemical parameters were sampled in three marked out stations between March 2018 and February 2020. Physicochemical parameters were analyzed following standard procedures, while macroinvertebrates were collected with Kick net and Van Veen grab. Physicochemical parameters showed that the water quality of the three stations sampled were fair considering the values of pH, turbidity, sulphate, nitrate, phosphate, DO, BOD, and EC which were within the World Health Organization and Federal Environmental Protection Agency of Nigeria. Cluster analysis based on Bray- Curtis similarity showed that macroinvertebrates were clustered by stations rather than seasons. A total of 5,580 macroinvertebrates individuals were recorded showing high biodiversity in the river. Diptera was the most abundant Order with 2,488 individuals followed by Odonata with 697 individuals. The least represented Order was Lepidoptera with 13 individuals. The diversity indices showed that Margalef index (5.93), Simpson diversity (0.95), Evenness (0.63), and Shannon-Weiner index (3.30) were highest in Station 1. This research work showed that the water quality of the studied stations was fair and station 3 was the most perturbed station. We recommend the enactment and enforcement of policies that will lead to aquatic ecosystem restoration.
Mostrar más [+] Menos [-]Environmental Geochemistry of some Heavy Metals and the Radioactivity in Urban Subsurface Soils, Southeast-Baghdad Texto completo
2023
Saleem Al-Ankaz, Zinah | Issa Muslim, Ruaa | Salman. Amana, Maitham
A geochemical evaluation was performed to determine the occurrences of many heavy metals as well as their natural activities, in the southeast-Baghdad. For this purpose, seventeen subsurface soil samples from the cited location were collected at a depth of 50-100 cm. Samples collection included many types of land uses such as open space, roadside, green land, industrial and commercial samples. The samples were characterized systematically using XRF and gamma-ray spectrometry with NaI (Tl) scintillation detector. The total average concentrations of heavy metals Ag, Sn, Sb, I, Hf, W, Th and U in the soil were 1.94, 3.13, 3.01, 2.82, 1.70, 72,5.66 and 0.85 ppm respectively. Heavy metals Sn, I and W appeared with high concentrations among the others as shown in total average, compared with the standard. The enrichment with Sn elements strictly appeared in green and commercial lands with an average 3.63 ppm, whereas I and W concentrated in industrial land 3.0 and 0.95 ppm respectively, indicating anthropogenic rather than autogenic. It was asserted that the observed elements can be used as pollution indicators to discover the state of the contamination. The EF values of the soils in some sites displayed enrichment with Sb and moderate with Ag reflected mild enrichment (EF > 2), confirming their level of pollution by the hazardous heavy metals. The contents of 238U, 232Th and 40K in the samples varied from 34.64-48.54, 47.22-67.73, and 323.27-585.11 Bq/kg, respectively. The mean activities of 238U, 232Th and 40K in the dry weight samples were correspondingly 41.25, 56.89, and 424.12 Bq/kg, which were higher than the global averages of 35, 30 and 400 Bq/kg, respectively. The radium equivalent levels in all samples were much lower than the global average (370 Bq/kg). In addition, all external and internal hazard indices were within the recommended limit. The average dose rate and gamma index levels were greater than the global average value.
Mostrar más [+] Menos [-]Engineering Properties of Substrate used in Constructed Wetlands Treating low Strength Sewage under Tropical Conditions Texto completo
2023
Vishwakarma, Smily | Dharmendra, Dharmendra | Singh, Rohit | Bharti, Bharti | Ankita, Ankita
Substrates play a major role to filter, adsorb, sediment, flocculate, precipitate, and exchange ions. In CW (Constructed wetland), selecting substrate or bed materials is not difficult, as locally accessible, cost-effective, and environment-friendly materials can be used based on size, hydraulic conductivity, texture, porosity, etc. CW substrates undergo a multitude of purification processes, including physical filtration and sedimentation, sorption, ion exchange and microbial degradation, precipitation, and bio-immobilization in the substrate, in addition to uptake and metabolism by macrophytes. With constructed wetlands, treatment facilities with well-defined substrates, vegetation species, and flow patterns can be built with greater control than with natural systems. This report details investigations of some of the locally available substrates that all fit the requirements. Based on analysis of parameters which are pH, water absorption capacity, hydraulic conductivity, porosity, surface area, bulk density, particle size distribution, D10 particle diameter, D60 uniformity coefficient, permeability and specific gravity, a comparison of four materials is presented in this paper. The study found that the construction waste materials evaluated showed satisfactory physical properties for use as filler media in constructed wetlands for wastewater treatment.
Mostrar más [+] Menos [-]Water Quality Status of Mangrove Ecosystem in Bedono, Sayung, Demak, Central Java Texto completo
2023
Retnaningsih Soeprobowati, Tri | Jumari, Jumari | Wasiq Hidayat, Jafron | Muhammad, Fuad | Hanif Al Falah, Mirza | Kadek Dita Cahyani, Ni | Gell, Peter
Mangrove ecosystems have many functions for coastal areas, including ecological, social, and economic services. These functions have a systemic impact on the environment of other coastal ecosystems and human life. The mangrove ecosystem covering an area of 197.92 ha in Bedono, Demak Regency, Central Java was threatened due to the wave abrasion and high tides. Some parts of Bedono Village had become inundated and flooded permanently, zink as part of the ocean. This research was conducted to quantify water pollution in the mangrove ecosystem of Bedono Village using the Storage and Retrieval (STORET) method and the pollution index (PI). The fieldwork was conducted June 2022, by collecting water samples for laboratory analysis tests and in-situ water quality measurement. The parameter of the water quality that exceeded threshold of the Government Regulation of the Republic of Indonesia Number 22 of 2021 are the dissolved oxygen (DO) ranges between 4.39-8.78 mg L-1, BOD ranges between 30-32.4 mg L-1, phosphate ranges between 0.063-0.074 mg L-1, ammonia ranges between 0.148-0.48 mg L-1, Cr ranges between 0.071-0.21 mg L-1, and Pb ranges between 0.071-0.21 mg L-1. Based on the STORET method, the water quality in the mangrove ecosystem was found to be in the category of moderately (-16, for harbor function) – heavily polluted (-80, for tourism and -90, marine biota), whereas based on the PI index it was lightly polluted (1.77-4.12, for harbor function) – moderately polluted (11.06-13.83for tourism, and 9.96-11.85, marine biota).
Mostrar más [+] Menos [-]Evaluation of the phytotoxicity of a pesticide (TRACTOR 10E) based on Alpha-cypermethrin in two plant species: lentils (Lens culinaris) and watercress (Lepidium sativum) Texto completo
2023
Ayoub, Naamane | Nawal, Lamraouhi | Soumaya, Rafii | Nadia, Iounes | Amrani Souad, El
Tractor 10E is an Alpha-cypermethrin based insecticide. It is one of the commonly used insecticides. The toxic effect of this product was assessed using the Lens culinaris (edible lentil) and Lepidium sativum (watercress) test. The seeds of Lens culinaris and Lepidium sativum were subjected to 6 increasing concentrations of Tractor 10E (25, 50, 100, 200, 400 and 800mg/l) and the control (distilled water). After 7 days, weight, root and stem development were measured.The results of the statistical study revealed the notable effect of this toxic product on growth, especially at high concentrations for the two species which are the subject of plant toxicity tests. Stem length growth is the most sensitive parameter. IC50 is equal to 136.99mg/l for lentil and 136.42mg/l for watercress. The results of this study reveal that this alpha-cypermethrin insecticide has the ability to alter the growth of plants as non-target organisms, which imposes the effective use and management of these toxicants and even replacing them with biopesticides to preserve human health and the environment.
Mostrar más [+] Menos [-]Effect of Copper on Cadmium-Resistant Plants of Agrostis stolonifera Texto completo
2023
Aleksandrovich Gladkov, Evgeny | Nikolaevna Gladkova, Olga
Environmental pollution with heavy metals has a negative impact on lawn grasses. Heavy metals are one of the priority pollutants of anthropogenic ecosystems. Earlier, plants Agrostis stolonifera, resistant to cadmium, were obtained using biotechnological method. Plants that are resistant to one heavy metal may be cross-resistant to another. The assessment of the resistance of plants obtained by biotechnological methods to other heavy metals is of practical value. The object of our study was to lawn grass - Agrostis stolonifera L. The aim of this work was to assess the tolerance of the next generation descendants of the regenerant Agrostis stolonifera, resistant to cadmium, to one of the most phytotoxic heavy metals - copper. Cadmium -tolerant plants were more resistant to copper. The tolerance of cadmium – resistant plants to copper is associated with nonspecific mechanisms. However, the increase in plant resistance was not very significant. Therefore, it is more expedient to obtain plants that are resistant to copper.
Mostrar más [+] Menos [-]Reducing Environmental Pollutants by using Triorganotin(IV)-Tyrosine Complexes that Prolong the Life of the Polymers used in Outdoor Patios Texto completo
2023
R. Arraq, Rafid | G. Hadi, Angham | S. Ahmed, Dina | Zainulabdeen, Khalid | Hashim, Hassan | A. Ahmed, Ahmed | M. Yusop, Rahimi | H. Jawad, Ali | A. Mohammed, Salam | Al-Amiery, Ahmed | Yousif, Emad
When exposed to UV light at ambient temperature, three tri organotin (IV) complexes with tyrosine as a ligand (85–97% yields) were utilized as additives to prevent the photo-degradation of PVC films (40 μm thickness). The compounds were described using NMR (1H, 13C and 119Sn), IR, and elemental analysis. The compounds formed were assigned trigonal bipyramidal geometry depending on the spectrum data. Several Triorganotin (IV) tyrosine complexes were synthesized and mixed with polymers to form thin films (vinyl chloride). Up to 300 hours of UV light (wavelength: 313 nm) exposure was given to these films. A microscope, atomic force microscopy, and scanning electron microscopy were used to examine the surface morphology of the PVC films. Rapid UV-weathering was employed to determine weight loss and the production of certain functional groups, including carbonyl and polyene. Compared to pure PVC film, the films with manufactured complexes showed less undesired alterations. By absorbing UV light and scavenging peroxides, hydrochlorides and radicals. The polymer was photo stabilized by the triorganotin (IV)-tyrosine complexes (vinyl chloride). It was discovered that Ph3SnL has the fastest rate of PVC photostabilization.
Mostrar más [+] Menos [-]Analytical Methods for Extraction, Determination and Degradation of Diazinon in Soil Samples Texto completo
2023
Dehghan Abkenar, Shiva | khakipour, Nazanin | Ganjali, Mohammad Reza
Diazinon is an organophosphorus insecticide that was widely used in agriculture to control pests on crops. It acts as an acetylcholinesterase inhibitor, which means that it interferes with the normal functioning of the nervous system of insects, leading to their death. Diazinon can also have an impact on human health and the environment, as it can contaminate water and soil and pose a risk to non-target species, including humans and animals. This review paper shows the progress made in the last years in analytical methods applied for the purpose of extraction, detection and degradation of Diazinon as an important environmental pollutant. A variety of sampling and analytical methods have been developed to measure diazinon and its metabolites in different media. The most popular methods for the identification and analysis of Diazinon are liquid and gas chromatography, liquid-liquid extraction, and solid-phase extraction (SPE). The focus of this review is on the identification, measurement, and elimination of diazinon as a major soil pollutant. It begins with a discussion of analytical techniques, followed by an examination of methods for removing diazinon from soil.
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