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Distribution and Concentration of Pb, Cd, and Hg Metals Due to Land Use Influence on Sediment in Malili River, East Luwu Regency
2023
Nurhasmiati Nurhasmiati, Muhammad Farid Samawi, Mahatma Lanuru, Paulina Taba, Fahruddin Fahruddin and M. Tumpu
This research was conducted in the waters of Malili River, East Luwu Regency, with 4 observation points in Malili River East Luwu Regency, namely: (a) Southeast Sulawesi Sub Das (Point 1) namely Pongkeru village bridge, Coordinate point 12126.69’8°” E; (b) Larona Sub Das Karebbe basin bridge (Point 2), Coordinate point 12115.09’9°” E; (c) The meeting point of Larona sub-dash and Pongkeru sub-dash (Point 3), coordinate point 12159.64’8°” E; (d) Upper Malili River, Malili village, Malili bridge (Point 4), Coordinate point 12147.20’5°” E. Metal concentration and distribution were analyzed descriptively with the help of images (maps), graphs, and tables. Differences in Pb, Cd, and Hg metal concentrations in sediments between point locations were tested using analysis of variance (ANOVA) through the SPSS version 22 program. The relation between grain size, organic matter, and Pb, Cd, and Hg metal concentrations was tested using linear correlation. The results showed that the sediment content of Pb and Cd metal concentrations at each point location did not exceed NOAA (1999) quality standards. In the sediment, Hg metal concentration exceeds the quality standards of NOAA (1999) at each point, namely point 1. Pongkeru 0.590 μg.g-1, point 2. Karebbe 0.229 μg.g-1, point 3. Kawasule 0.514 μg.g-1 and point 4. Malili 0.358 μg.g-1. The relation between sediment size and Pb, Cd, and Hg metal concentrations at each point location has a weak correlation. The relation does not significantly affect the content of heavy metals in the sediment. It may be due to other factors, such as the source of heavy metal pollutants in each different point location. The relation between organic matter and the concentration of Pb, Cd, and Hg metals at each point location has a weak correlation. The relation does not significantly affect the content of heavy metals in the sediment because it may be due to other factors, such as different sources of heavy metal pollutants in each point location.
Afficher plus [+] Moins [-]Effectiveness of the River Chief System in China: A Study Based on Grassroots River Chief’s Behavior
2023
Wenjie Yao and Ming Cheng
The River Chief System is an administrative model of water environment governance currently adopted in China. Under this system, the chief CPC and government leaders at various levels serve as “river chiefs” and are responsible for organizing and directing the management and protection of the rivers and lakes within their remit. This paper tries to reveal the actual effectiveness of the River Chief System based on the behaviors of grassroots river chiefs (GRCs). First-hand data about GRCs is obtained through a questionnaire survey. Whether the water environment governance target is achieved and the water quality change of the river sections in the charge of GRCs is quantitatively assessed It has been found that, except for implementing “one policy for one river” and making river patrols, the behaviors of GRCs have no positive effect on river pollution prevention and control, implying the ineffectiveness of the River Chief System. The framework design of the River Chief System should be optimized, and a system with professionals to support GRCs in performing their duties should be established. Moreover, the tendency to use environmental regulation as a mandatory policy tool should be weakened. These measures are of great practical significance to the implementation of the green development concept and the furthering of the River Chief System overall.
Afficher plus [+] Moins [-]Synthesis of Persea Americana Bio-Oil and Its Spectroscopic Characterization Studies
2023
V. Hariram, Pavan Kumar Reddy, B. Gajalakshmi, S. K. Siraj Basha, A. Saravanan, S. K. Khamruddin and B. Ravikumar Reddy
The present investigation aims to evaluate the feasibility of using Persea americana (Avocado) biodiesel in compression ignition engines. Persea americana bio-oil was extracted through a soxhlet extraction process using n-hexane solvent after careful pre-processing of the feedstocks. Since the Free Fatty Acid content was 1.78% estimated through titration, single stage base-catalyzed transesterification technique was adopted using methanol and sodium hydroxide as catalysts in the molar ratio of 1:6. Gas Chromatography-Mass Spectrometry analysis revealed the presence of Oleic acid in major proportions. The Fourier transform Infra-Red analysis confirmed the presence of carbonyl group ester ions between 722.19 cm-1 and 1460 cm-1. The 13C NMR and 1H NMR studies supported the successful transformation of triglycerides into Fatty Acid Methyl Esters with distinct peaks at 3.369 ppm and 48.147 ppm, respectively.
Afficher plus [+] Moins [-]Efficacy of Tree Leaves as Bioindicator to Assess Air Pollution Based on Using Composite Proxy Measure
2023
J. S. Berame, J. E. Josue, M. L. Bulay, J. J. Delizo, M. L. A. Acantilado, J. B. Arradaza and D. W. M. G. Dohinog
Air pollution has become a major issue in cities due to urbanization, population growth, industrial development, and increasing number of vehicles. The study used Gmelina arborea tree leaves as a bioindicator to determine the Air Pollution Tolerance Index (APTI) as a simple and effective compositional index of environmental health in three cities in the Caraga Region, Philippines. To calculate the APTI, four biochemical parameters of tree leaves were calculated: relative water content, total chlorophyll content, leaf-extract pH, and ascorbic acid content. In terms of the APTI category, results showed that all G. arborea species collected in all sample sites are classified as sensitive to air pollution, with the sample collected in Bayugan City being the most sensitive, with an APTI value of 7.66, and the samples collected in Butuan and Cabadbaran City being the least sensitive, with APTI values of 9.54 and 9.11, respectively. A Kruskal-Wallis test revealed a significant difference between the APTI values of G. arborea trees in the three sampling areas in the Caraga region. Based on the APTI computed values of the tree leaves determined in all sites, it is concluded that G. arborea species can be used as a bioindicator of air pollution, classified as sensitive.
Afficher plus [+] Moins [-]Variance-Based Fusion of VCI and TCI for Efficient Classification of Agriculture Drought Using Landsat Data in the High Atlas (Morocco, North Africa)
2023
Fathallah Fatima Ezzahra, Algouti Ahmed and Algouti Abdellah
Drought assessment using drought indices has been widely carried out for drought monitoring. Remote sensing-based indices use remotely sensed data to map drought conditions in a particular area or region. Therefore, the objective of the present study is to make a study on drought risk based on the calculation of an indicator from biophysical parameters extracted from NOAA/AVHRR satellite data, namely TCI and VCI, to obtain a better understanding of the differentiation between each index, and their application for drought monitoring in the High Atlas of Marrakech on the Chchaoua Morocco watershed during 1980-2020. Landsat oli7 and8 data were used to construct the indices. The result showed that each index proved to be a useful, fast, sufficient, and inexpensive tool for drought monitoring. However, each index has its differences. The TCI was found to be drought sensitive during the dry season or in months when high temperatures occurred. While VCI detected drought more sensitively in the rainy season as well (December-January-February to May) than TCI and VCI. Meanwhile, VCI, including the improved TCI, combined two indicators to better understand drought occurrence. These indices were calculated using GIS, QGis, ArcGis satellite imagery scenes, and Landsat. After a comparative study of these years, from 1984 to 2020, the evolution of the VCI and TCI was highlighted.
Afficher plus [+] Moins [-]A Master Plan Realization for an Integrated and Sustainable Management System for Household and Similar Wastes in Morocco’s Landfills by Sizing a Methanation and Composting Unit
2023
Akram Farhat, Ayoub Aziz, Kaoutar Lagliti and Mohammed Fekhaoui
This work is a decision support contribution in Morocco’s household and similar waste management. This management based on total waste landfilling leads to several environmental impacts, such as the use of large land areas, also the gaseous pollutants released, such as methane. Our first action was to collect reference data on the composition of this waste through a physicochemical characterization in the landfill in the city of Mohammadia. We sorted the waste generated by four types of populations with different living standards. A quantity of 500 to 2315 kg was treated, which allowed us to classify the household waste studied into nine main components. The sorting results are (organic matter 54.94%, plastic 15,18%, paper and cardboard 9,72%, textiles 7,46%, sanitary textiles 5,82%, metals 2,20%, glass 1, 89%, Wood 1,82% and Other 1,28%). Thus, these results revealed organic matter dominance and an increase in the plastic rate, which did not exceed 8% in the past. Added to this, the physicochemical parameters results are (volatile matter 60,26%, Humidity rate 59,05%, a total organic carbon (TOC) 33,47%, and a lower heating value (LHV) 1840,3 kcal.kg-1). From these data, we can easily deduce that installing a sorting platform with a methanation and composting unit is the most suitable choice for recovering our waste. Therefore, we have chosen the methanation technology that meets the results obtained (dry batch and mesophilic) and sized this unit to assess its electricity production capacity that can be produced in our landfills. We carried out a scenario with a load factor of 0,9 and an electrical efficiency of 39%. The study results are 9 digesters to be built, 6.700 MW.y-1 of electrical energy produced, 14.523 tons.y-1 of refined compost, and 2.128.680 m3.y-1 of biomethane produced. By offering our own integrated and sustainable management system for household and similar waste, we have connected the landfill bins and the digesters to the same motor to avoid biogas leaks from the bins to the atmosphere and increase electrical efficiency by controlling the gas flow.
Afficher plus [+] Moins [-]Study on the Experimental Conditions of Adsorption of Lanthanum (III) on Boron Nitride Nanosheets
2023
C. Fu, Y. He, C. Yang, J. He, L. Sun, G. Sheng, X. Zhang, L. Wang, L. Li and W. Linghu
This paper investigated the adsorption properties of boron nitride materials for La(III), and the possible action mechanism was put forward based on experiments. Then the boron nitride materials were characterized by SEM, TEM, XRD, and FT-IR before and after adsorption. In addition, the effects of pH, the amount of adsorbent, the concentration of La(III) solution, and adsorption time on the adsorption efficiency were also investigated. It is found that under a certain amount of adsorbent when the pH is 7.0 and the concentration of La(III) is 40 mg.L-1, the adsorption ability of La(III) is the best. The maximum adsorption capacity is 201.45 mg.g-1. The adsorption kinetic data are in good agreement with the pseudo-second-order and intra-particle diffusion models. These results show that boron nitride has a good application prospect for removing and recovering La(III) in water and has a certain practical application value.
Afficher plus [+] Moins [-]Systemic Economic Viability of Informal Sectors: E-Waste Management
2023
Dharna Tiwari, Gautam Mehra and Nidhi Gauba Dhawan
The informal sector has been at India’s core of recycling WEEE for the last few decades. They do not have the scientific knowledge of processing e-waste and use acid baths and heat treatment to extract precious metals. The existing processes used by informal actors lead to a serious impact on their health as well as the environment. The introduction of advanced recycling technology for mitigating the hazardous effects on the environment and human health is as important as the development of technology for new-age electronic products. The social, economic, and environmental benefits to the informal sector can ensure formalized livelihoods in e-waste recycling by ensuring access to technology. The paper highlights how setting up a recycling facility and capacity building of the informal sector solves the problem of informality and its associated social, economic, and environmental evils, which will benefit the sector as a whole.
Afficher plus [+] Moins [-]New Frontiers in the Bio-inspired Green Synthesis of NiO NPs and Their Applications: An Overview
2023
Waseem Ahmad and Ankita Rawat
Nanoparticles are an important tool for new updations and advancements in diverse sectors. The inorganic metal and metal oxide nanoparticles have enormous research interest because of their great relevance in medicine, wastewater treatment, catalysis, biotechnology, and in the formation of energy storage devices. The NiO NPs can be synthesized using different physical and chemical methods and exploring all their possible applications. Green synthesis is the easy, safe, and effective nanoparticle synthesis route. Green metal and metal oxide nanoparticle syntheses provide the most affordable, convenient, and biocompatible approach for fabricating NiO NPs. This way is a good alternative to the conventional methods of synthesis. Green synthesis, being more constructive, is widely used in research and gives promising outcomes. This review highlighted the unique feature of the NiO nanoparticles. This paper brings forth the usage of green synthesis for synthesizing NiO nanoparticles. It also provides readers with a collective review of the recent development in the green synthesis of NiO NPs and their potential application in different fields.
Afficher plus [+] Moins [-]Integrated Method of Ozonation and Anaerobic Process for Treatment of Atrazine bearing Wastewater
2023
Saba Khurshid, Abdur Rahman Quaff and Ramakar Jha
The paper presents the treatment of atrazine-contaminated wastewater by ozonation followed by an anaerobic process using Upflow Anaerobic Sludge Blanket (UASB) reactor. The experiment was performed with 100 ppb synthetic solutions of atrazine prepared in ultra-pure water. The corresponding initial Chemical Oxygen Demand (COD) is 226 mg.L-1. The initial pH was adjusted to 9.5. The atrazine-bearing synthetic wastewater was ozonated with an ozone dose of 9.4mg/l for 40 minutes of optimum ozonation time, resulting in a 35% reduction in the initial concentration of atrazine. Along with atrazine reduction, there was a COD removal of 54.42%. Further, it was degraded with an anaerobic process, resulting in the final reduction in atrazine concentration of 81% and the corresponding removal in COD of 86.7%. The process of ozonation led to the mineralization of atrazine and enhancement in the biodegradability of the wastewater. Using ion chromatography, the ozonated wastewater sample was analyzed for ionic by-products before and after ozonation. The ion chromatography results showed the breaking of the atrazine compound and the formation of Cl-, NO3-, SO42-, and F- as intermediate products. Further, the BOD5/COD ratio increased, reflecting the increased biodegradability. This ozonated wastewater was treated in a UASB reactor where the pesticide was degraded to 19 ppb, and COs degraded to 30 mg.L-1. The overall removal of atrazine pesticide and COD were 81% and 86.7%, respectively, in the integrated system of ozonation followed by anaerobic degradation.
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