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Efficacy of Tree Leaves as Bioindicator to Assess Air Pollution Based on Using Composite Proxy Measure 全文
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.
显示更多 [+] 显示较少 [-]Variance-Based Fusion of VCI and TCI for Efficient Classification of Agriculture Drought Using Landsat Data in the High Atlas (Morocco, North Africa) 全文
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.
显示更多 [+] 显示较少 [-]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 全文
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.
显示更多 [+] 显示较少 [-]Study on the Experimental Conditions of Adsorption of Lanthanum (III) on Boron Nitride Nanosheets 全文
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.
显示更多 [+] 显示较少 [-]Systemic Economic Viability of Informal Sectors: E-Waste Management 全文
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.
显示更多 [+] 显示较少 [-]New Frontiers in the Bio-inspired Green Synthesis of NiO NPs and Their Applications: An Overview 全文
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.
显示更多 [+] 显示较少 [-]Integrated Method of Ozonation and Anaerobic Process for Treatment of Atrazine bearing Wastewater 全文
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.
显示更多 [+] 显示较少 [-]Microplastic Pollution in Seawater: A Review Study 全文
2023
Sheela Upendra and Jasneet Kaur
Due to its detrimental effects, notably on the well-being and biota of the ocean, microplastic contamination is becoming a bigger concern. Because of this, the issue of microplastics in the marine ecosystem is currently a major concern. The purpose of the study is to objectively evaluate the most recent data supporting the impact of microplastic contamination in seawater. When creating the standards for assessing the literature, P.I.C.O. was taken into account. For this inquiry, databases were selected and used throughout the data-collecting process. We checked PubMed, CINAHL, Google, Hinari, and the Cochrane Library. Boolean operators (AND, OR) and keywords were employed in the search to avoid oversaturating the data. Keywords used as per MeSH: Microplastic, plastics, seawater, ocean, pollution, microplastic exposure. The last five years (Since 2017) worth of studies were incorporated. Boolean search for relevant terms used. This limited my query to 188 records through various database searches. Several things were removed because they were unrelated to the study’s subject. Due to its detrimental impact on marine biota, the issue of microplastic contamination in the marine ecosystem is a current concern. Microplastics, which serve as a vector, become stuck with harmful pollutants. It is necessary to implement conservation management strategies and assistance for different educational programs to protect the environment from these hazardous microplastics. Humans are exposed to plastic waste when eating fish tainted with plastic. As a result, there are various outbreaks of chronic diseases, and people suffer the effects. The public’s education on the harmful effects of microplastics is a crucial need in this field. As a result, many inventions would be promoted to decrease the use and consumption of plastic and its products.
显示更多 [+] 显示较少 [-]Process for the Reduction of High Water Content from Oily Sludge and Scum by Hot Washing 全文
2023
Le Zhang, Longlong Yan, Huan Zhang, Zhe Shen, Si Chen, Tao Yu, Chengtun Qu
The reduction of oily sludge and scum with high water content by hot washing and analysis of the main factors that affect the reduction and oil recovery rate of oily sludge and scum in hot washing were investigated. Best process conditions for the reduction of tank bottom sludge, refining sludge, and oily scum were carried out, which can make the oil recovery rate and reduction rate of tank bottom sludge after reduction reach 96.30% and 93.00%, respectively, the oil recovery rate and reduction rate of refining sludge after reduction reach 95.36% and 92.60% respectively, and the oil recovery rate and reduction rate of oily scum after reduction reach 95.92% and 93.60% respectively. After treatment, the oil content of the residue is reduced to below 5.1%, and the water content is reduced to below 59.0%. Oil content in the separated water is lower than 200 mg.L-1, and the water content in the separated oil is lower than 0.2%, far below the requirement of 0.5% in the oilfield’s crude oil gathering and transportation standard.
显示更多 [+] 显示较少 [-]Analysis of Solid Waste in Hospitals of Lahan and Rajbiraj Municipalities, Madhesh Province, Nepal 全文
2023
R. S. Mehta, R. C. Adhikari and B. B. Bist
Hospital waste is a burning issue that severely impacts public health. This study in three big hospitals in Lahan and Rajbiraj, Nepal, for one year (2019 March-2020 February) aims to analyze some parameters that directly help waste management properly. Field study, questionnaire, and interview methods were followed. The average moisture content of wastes of all three hospitals was 55.79%. There was no variance in the three hospitals’ moisture content values of wastes (F = 1.89 P-value = 0.165 F crit = 3.284917651). The average temperature of dumped waste was 23.23°C, and the temperature of all three hospitals was closely associated (F = 0.998, P-value 0.379, Fcrit = 3.28). The average pH value of wastes from the three hospitals was 4.44, and it from all three sites was strongly associated (F = 0.0668, P-value 0.935, Fcrit = 3.284). There was no relation between income and types of waste production (ꭕ2 = 0.8, df = 4, significance level = 0.05), but there was a high association between the level of income and amount of waste production. There was a high association between the nature of hospitals and types and the amount of waste (ꭕ2 = 77.09, df = 4, Significance level = 0.05). In Sagarmatha Choudhary eye hospital Lahan, there was no significant correlation between the number of patients and the amount of waste (Correlation = -0.187889 at 0.05% significance level). Unique Hospital Rajbiraj showed a correlation between the number of patients and the amount of waste (correlation = 0.1183 at 0.05% significance level). In Gajendra Narayan Singh Hospital, there was a correlation between the number of patients and the amount of waste (Correlation = 0.3453, at 0.05% significance level). There was no association between the qualification of respondents and their responsibilities regarding the services provided by hospitals (ꭕ2 = 1.43, df = 6, Significance level = 0.05). It is recommended for better management and installment of modern technologies for waste management.
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