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Concentration of Toxic Heavy Metals and Phytochemicals in a Medicinal Plant (Asclepias fruticosa) Collected Around Mining Areas in Brits, Pretoria
2023
Mugivhisa, L. L. | Mzimba, D. | Olowoyo, J. O.
The use of African traditional medicine in rural and peri-urban areas is common due to its affordability and accessibility. The study aimed to determine the levels of toxic heavy metals in the medicinal plant (Asclepias fruticosa) samples collected around three mining areas in Brits using ICP-OES. The phytochemical screening analysis was done to indicate the absence or presence of different phytochemicals in the medicinal plant. The results of the qualitative phytochemical analysis indicated the presence of flavonoids, alkaloids, proteins, and carbohydrates in Asclepias fruticosa collected from all the mining areas. The results of the heavy metals showed that the mean highest concentration for all the heavy metals was recorded for Mn from the leaves of the medicinal plants. The trend in the heavy metals accumulation was roots > leaves > stems from all the sites, and the differences were significant (p < 0.05). The range of heavy metals in the plant was in the range Mn (12.33 ± 2.31-85.33 ± 51.07 μg.g-1), Zn (10.67 ± 0.58-60.33 ± 0.56 μg.g-1), Cr (3.43 ± 0.06 -34.90 ± 0.10 μg.g-1), Cu (8.67 ± 0.12-18.8 ± 1.57 μg.g-1), Ni (5.67 ± 0.12-23.23 ± 1.7 μg.g-1) and Pb (0.53 ± 0.013-1.59 ± 0.15 μg.g-1). The values of the heavy metals Cr, Zn, and Ni in the plant exceeded the recommended limits set by WHO for human consumption. Heavy metals in the medicinal plant were accumulated in the roots and not translocated to the stems and leaves. It is therefore recommended that communities staying around the mines should be discouraged from picking and using medicinal plants growing around the mines and should be educated on the safety of medicinal plants growing around the mines.
Show more [+] Less [-]Water Quality Assessment of Wenyu River with Variable Weight Cloud Model
2023
Guojiao, Li | Baohui, Men | Lehao, Wang
The water resource is an important guarantee of social and economic sustainable development. The improvement of water’s ecological carbon sequestration ability is a direct response to the goal of “double carbon”. Water quality directly affects its carbon sequestration capacity. So it is necessary to understand the water quality of rivers. In view of the fuzziness and uncertainty in water quality evaluation, this paper uses the cloud model to realize the qualitative to quantitative transformation of water quality in Wenyu River. By combining moment estimation theory with critic weight, AHM weight, and variable weight theory. A water quality evaluation method integrating a variable weight cloud model is constructed. And the temporal and spatial changes in water quality in Wenyu River are studied. The results show that the combined weights balance the influence of each index while retaining the advantages of subjective and objective weights. The results of the water quality evaluation are consistent with the practice, which verifies the feasibility and applicability of the method.
Show more [+] Less [-]The Study of Filamentous Fungi in Potable Water and Its Biofilm Formation in Water Pipeline System
2023
Asha, S. | Vani, G. Sangeetha
Water is essential for life and it is an inorganic constituent of living matter. Water pipeline systems are sighted as problematic in aquatic habitats in which multiple pathogens are occupied including fungi. They have rigid cell walls containing glucans and chitin. The bodies of fungi comprise filaments called hyphae. These hyphae are split into a mat of interwoven single cells made of mycelium. Fungi can pollute the drinking water system and are responsible for biofilm formation. Biofilms are complex polymers containing many times their dry weight in water. Moisture is essential for biofilm formation. The occurrence of biofilms affects the quality of drinking water. Hence, the present study is aimed at recovering the fungi from drinking water samples and their biofilm formation in the water pipeline system. Drinking water samples such as mineral water, tap water, and RO-purified water are collected from different places. Fungi such as Aspergillus, Penicillium and Mucor were recovered from these samples and most species belong to Aspergillus and Penicillium. Further, the biofilm formation of fungi from cast iron in the pipeline system was detected using fluorescence microscopy and fluorescent in situ hybridization analysis.
Show more [+] Less [-]Influence of Different Particle Sizes of Sediments on the Lower Reaches of the Basin and its Significance in the Liao River Governance
2023
Yang, Chen
Based on the sand volume and sedimentation volume data for different particle size (PS) groups, the relationship between the annual scouring and silting amount of the Juliu River-Liujianfang section and the yearly sediment volume entering the downstream river channel was established. The critical values of sediment storage and release for the downstream river channel were obtained. It was found to decrease with an increase in the sediment particle size. The correlation coefficient between the annual scouring and silting amount of the Juliu River-Liujianfang section and the annual sediment volume entering the downstream river channel increased with the coarsening of sediment PS. It indicated that the sediment size was proportional to the sediment amount (SA) entering the river channel. As the sediment size increased, the deposition amount increased due to the variation of unit sediment amount. Based on the treatment and achievement of source areas with sediment sizes larger than 0.05 mm, it is significant to concentrate on treatment areas with sediment sizes larger than 0.10 mm.
Show more [+] Less [-]Study of Some Stability Parameters in the Atmosphere of Oil Al-Dura Refinery, Southeast Baghdad
2023
Lagenean, Farant H. S. | Naif, Salwa S. | Al-Jiboori, Monim H.
Wind and temperature measurements at an oil refinery site located southeast of Baghdad city at two levels, 15 and 30 m, are presented. Three schemes are used to determine different stability classifications: Monin-Obukhov length, gradient, and bulk Richardson numbers. Meanwhile, vertical changes in air temperature and wind shear are also computed. There were lapse rate and inversion cases during the nights and days while favorable wind shear was dominant. The variation of stability in each scheme is large, covering the entire range of stability for a given class. The results of stability schemes are compared to each other. The results show that the schemes based on gradient and bulk Richardson numbers reasonably compare them.
Show more [+] Less [-]Retention Behaviour of Heavy Metals from Industrial Sludge Amended with Admixtures to Use Them as Liners for Landfill Facilities
2023
Saranya, S. S. S. | Maya Naik, S. N. | ., Shankara
The solidification of contaminants within the soil/waste has proved to be a versatile technique to de-contaminate them and make them usable for several applications. In this method, the development of binder provisions leads to the conversion of the environmentally unstable condition of waste materials into a nearly stable material. Further, these materials pose a minimum threat that can be absorbed into the environment. Normally lime/cement and other pozzolanic materials are used as binder materials. In this work, it is proposed to use the efficiency of binding fly ash to improve the unconfined compressive strength (UCC) of soils, particularly during the curing period. This is because improvement in strength is a reflection of the improvement of bonding soil particles. Fly ash as the main source material, in addition to a minor proportion of cement and lime, is used to determine the strength. UCC test results revealed that as the percentage of fly ash increases there is an increase in compressive strength. It is also observed that with an increase in lime content and an increase in cement content, the UCC strength also increases. The strength in cement-stabilized compacted specimens is more compared to lime-stabilized mixtures. To confirm that the improvement in strength is related to the solidification of contaminated metals, particularly for soils containing copper and chromium, the stabilized mixture is tested for the leaching of these metals. Leaching tests were conducted on various stabilized mixtures at different curing periods. The leachate was examined for metal ion concentration using Atomic Absorption Spectrophotometer. The leaching behavior of heavy metals from different proportions of soil matrix revealed that with an increase in lime or cement percentage, a decrease in leachability is observed. It is found that the leaching of heavy metals from cement-stabilized soils was lower than in lime mixture combinations. However, minimum strength improves the solidification and retention of heavy metals effectively.
Show more [+] Less [-]Efficiency of Paecilomyces variotii in Bioremoval of Reactive Black Dye from Tannery Effluent
2023
Chokkalingam, Priya | Anamalagundam, Mahi | Lahari, Chaithanya | Singh, Shreya | Kumar, G. Mohan | Hari, Rajeswary
The present work investigates the efficiency of Paecilomyces variotii upon degrading Reactive Black dye which has been termed a recalcitrant variety of synthetic dye. In this research, initially a predominant fungal species, Paecilomyces variotii was isolated from the tannery effluent sample. The study was carried out by assessing the ability of fungi to decolorize the dye under various parameters like pH (5,7 and 9), Temperature (7°C, 30°C, and 45°C), Dye concentration (200, 300, and 400 mg/L) for different incubation or exposure time interval (3, 5 and 7 days). From the experimental study, it was found that Paecilomyces variotii showed a maximum percentage of dye decolorization at 7°C at pH 9 with 75%, at 30°C at pH 7 with 85%, at 45°C at pH 5 with 82% and a maximum period of incubation with 7 days in 200 mg.L-1 concentration. This result conveys that the strength of Paecilomyces variotii in decolorizing the synthetic dye is effective at a moderate temperature with neutral pH for maximum exposure time. So Paecilomyces variotii could be a good candidate of choice for the biodegradation of various synthetic dyes when manipulated wisely. Also, the result sparks a positive attribute toward decreasing industrial wastewater pollution.
Show more [+] Less [-]Utilization of Waste Glass for Enhancement of Chemical Properties of Concrete
2023
Gupta, Jagriti | Jethoo, A. S. | Lata, Nandeshwar
The world is facing a huge problem of waste generation; among these, solid waste in the form of glass has become a prime concern for the environment. The composition of the glass is silica-based, and its utilization in the preparation of concrete can be an efficient step in the direction of sustainable development by reducing the cement content. The formation of secondary calcium silicate hydrates (C-S-H) could take place due to the pozzolanic reaction of the fine ground glass with the cement. TGA techniques were used in this research to investigate the chemical properties of the waste glass, and later, these were compared with the properties of the cement. By keeping a constant w/b ratio for all the replacement levels from 0% to 35%, the evaluation of the workability and compressive strength were done. The evaluation showed that workability increased with an increase in the content of the waste glass. With 7 and 28 days cured samples, the strength and chemical investigation were conducted on the samples prepared with the same mix design. Constant Dose of superplasticizer used by weight of cement for mixes as 0.8%. Compared with the control sample, The level of replacement of waste glass to cement as 30% has depicted the augmentation in the compressive strength. Thus, the use of waste glass was found to be cost-effective and an environment-friendly solution for the sustainable development of concrete.
Show more [+] Less [-]A Coupled Study on Carbon Emission Assessment and Emission Reduction Coupling of Tourism Activities in Beautiful Countryside Taking Zhahan Village, Qiongzhong County, Hainan as an Example
2023
Zhu, Liping | Zhou, Yadong | Li, Qing
Taking Zhahan village in Qiongzhong County, Hainan, as an example, and based on its 160,000 tourist arrivals in 2019 and taking into account the real circumstances of Hainan, this research composes the emission models of carbon emissions from tourism transportation, tourism accommodation, tourism catering, other tourism activities and pollutants in this village. The outcomes indicate that Zhahan village's tourism catering consumes the most energy and emits the most carbon, accounting for 53.95% of all carbon emissions. Furthermore, the emission of tourism accommodation is the second, occupying 24.13%. Then, its tourism waste emission is the third, constituting 13.61%. In addition, its annual sewage discharge from tourism activities amounts to 15,144 t. This article promoted 1MW photovoltaic and 10 square solar hot water in the entire village, scientifically developing the evaluation system of rural tourism carbon emission, and making a low carbon brand of emission reduction coupling. The research and operation can be replicated and extended to enable the harmonious development of tourism development and organic unity of energy resource utilization.
Show more [+] Less [-]Radiation Risk Among Children due to Natural Radioactivity in Breakfast Cereals
2023
Abbas, H. H. | Kadhim, Shaymaa A. | Alhous, Shatha F. | Hussein, H. H. | AL-Temimei, F. A. | Mraity, H. A. A.
Breakfast cereal is one of the common foods for children’s nutrition. It is made from sugar, barley, calcium carbonate, salt, maize, peanuts, molasses, and honey. Therefore, assessing the levels of radioactivity in breakfast cereal is essential for children’s health. Gamma-ray spectrometry NaI(Tl) was used to measure the radiation hazard in ten samples collected from the Iraqi market. The corresponding radiation dose quantities and hazard indices were also calculated. The average concentrations of 226Ra, 232Th, and 40K were found to be 18.195, 20.965, and 796.500 (Bq.kg-1). The annual effective dose equivalent (AEDEin), annual ingestion dose (AID), and the risk of cancer incidence (ELCR) were all seen to be within the accepted levels, except the annual gonadal equivalent dose (AGED). Radiation hazard index values (i.e., Iγ, Iα, and Hin) were noticed to be lower than unity, except Iγ was much higher than the internationally permissible limits for the samples of BGF5, BGF6, and BGF7 recommended by UNSCER2000. Therefore, the study findings reveal that this type of cereal can be considered a safe feeding material for children’s health.
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