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النتائج 451 - 460 من 576
Sustainable Alternative Materials to Concrete Masonry Partition Walls: Light-Weight Wall Panel Using Polymethyl Methacrylate (PMMA) and Shredded Waste Metalized Film Packaging النص الكامل
2023
R. C. G. Prado and T. A. Amatosa Jr.
The amount of plastic waste produced yearly is significantly increasing. Approximately 300-400 million metric tons of plastic waste are produced yearly. One of the dominant plastic wastes is a metalized film, a shiny, non-homogeneous polymer used in packaging that is considered the least recycled. Meanwhile, partition walls in buildings are traditionally made of concrete masonry, one of the most utilized materials in the construction industry globally, consumed yearly by about 11 billion metric tons. Because of the excessive use of concrete, the necessary raw materials are undeniably depleting, therefore demanding some alternatives. Polymethyl methacrylate (PMMA) is one option that can be utilized as an alternative because of its remarkable characteristics better than that of the traditional. This paper proposed the utilization of PMMA in fabricating the hollow panel filled with shredded waste metalized film packaging resulting in the lightweight wall panel being used as an alternative to concrete masonry for constructing partition walls. After the experiment, PMMA produced compressive strength of 75.30-84.30MPa, a tensile strength of 52.00-59.10MPa, a flexural strength of 102.00-107.00MPa, and water absorption of 0.80-0.90%. Also, shredded waste metalized films add aesthetic to the panel and are complemented by the remarkable transparency of PMMA. In conclusion, using this lightweight wall panel instead of traditional concrete masonry partition walls will reduce plastic waste in landfills and the raw materials necessary to produce concrete.
اظهر المزيد [+] اقل [-]Integrated Method of Ozonation and Anaerobic Process for Treatment of Atrazine bearing Wastewater النص الكامل
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.
اظهر المزيد [+] اقل [-]Synthesis and Characterization of Cellulose Acetate Membrane from Cassava Peel for Microfiltration النص الكامل
2023
A. Ma’ruf, E. Puspawiningtiyas, D. N. Afifah and E. Diaz
Cassava peel is a waste product from cassava starch or modified cassava flour (mocaf) production. It is currently not utilized optimally. Cassava peel is a lignocellulosic material that can be used as a source of cellulose. Acetylation of cassava peel cellulose was successfully done using acetic anhydride with glacial acetic acid and sulfuric acid as catalysts. The content of acetyl is 49.54%, and the degree of substitution (DS) is 3.69. The percentage of acetyl of more than 43% and the DS of 3.69 show that the cellulose acetate obtained is categorized as cellulose triacetate. The CA–PEG membrane has a pore range of 1- 4 μm depending on the molecular weight of PEG. The coefficients of rejection of the CA-PEG membrane range from 95.99% to 98.88%. The CA-PEG membrane is effective as a microfiltration membrane.
اظهر المزيد [+] اقل [-]Spatial Model of Post-Earthquake Spring Performance in the Watershed Areas النص الكامل
2023
Akhbar Akhbar, Naharuddin Naharuddin, Adam Malik, Rahmat Kurniadi Akhbar and Sudirman Daeng Massiri
The 7.4 Mw of tectonic earthquake caused liquefaction in Pasigala on September 28, 2018, happened due to the fault movement of Palu-Koro. It affected the water availability every spring. The research aim is to determine the spatial model of water production every spring after the natural tectonic disaster, especially in Palu and Poboya watersheds-a model built based on the integration between the spatial data overlaying and the statistical regression correlation. The sites are purposively selected at six springs spots and divided into four clusters (Poboya, Uemanje, Ranjuri Beka, Mantikole). The model assessment was generated based on the springs’ performance from x variables (catchment area, land cover, aquifer, free-ground water depth, fault, number of springs users) and the y variable (water discharge). The result shows that Poboya’s performance is bad-disturbed, while Uemanje, Ranjuri, Beka, and the performance of Mantikole are disturbed. The bad performance of springs requires conserving watershed areas through forest and land conservation, tree enrichment planting, wise land management, and good water use.
اظهر المزيد [+] اقل [-]An Attempt to Reduce the Electrocoagulation Costs and to Ensure the Reuse of Treated Aqueous Dye Solution النص الكامل
2023
D. Jovitha Jane, M. S. Asath Murphy, Riju S Robin, S Sahaya Leenus, Jegathambal Palanichamy and Parameswari Kalivel
In most of the research works, similar metal electrodes were used, resulting in high operating costs, and the reuse of the treated water was not explored. The major goal of this research is to lower the cost of the electrocoagulation (EC) process by employing electrodes made of different metals and to investigate whether it is possible to reuse the water that has been treated by doing so. It was done to optimize the operational parameters such as pH, voltage, time, electrolyte, and dye concentrations. The energy and electrode consumption was calculated as 0.29 kWh.m-3 and 3.5×10-2 kg.m-3, respectively. The HPLC and LC-MS studies shows the degradation of dye and the formation of intermediary compounds, which were less toxic. The sludge obtained from the EC process was subjected to EDX and XPS analysis to know the composition of metals and the formation of metal hydroxide coagulants. The phytotoxicity of the treated water after EC was examined using Trigonella foenum-graecum seeds. The results showed an utmost color removal efficiency (CRE%) and COD removal of 99.78% and 92.86% with an operating cost of US$ 0.028, which is comparatively 98.12% lower than the other conventional electrodes. The treated toxicity test of water was comparable to the toxicity test of tap water.
اظهر المزيد [+] اقل [-]Negative Effects of the Urban River Pollution on the Environment and Human Health in Bangladesh النص الكامل
2023
Kudrat-E-Khuda (Babu), Md. Riaduzzaman, Tahmina Akter and Sumaia Akther
Based on research findings, Bangladesh’s river water, crucial for domestic, agricultural, and industrial use, has long been in a terrible situation. There have been numerous instances of significant contamination in the waterways surrounding Dhaka city, including the Buriganga River, and in Chattogram city, including the Karnaphuli River, over the past 40 years. The existing data demonstrate that other urban rivers, particularly Karatoa, Teesta, Rupsa, Pasur, and Padma, are also in severe condition due to the disposition of huge pollutants. Contaminants flowing with the water have severely polluted the downstream areas of the rivers. High metal concentrations are frequently observed in river water during the dry season. In the Buriganga River and at certain locations in the Turag, Balu, Sitalakhya, and Karnaphuli Rivers, the presence of dissolvable oxygen (DO) is nearly zero. NO3, NO2, and PO4-3 pollution has also occurred in many rivers. Most rivers have Cr, Zn, Fe, Pb, Cu, Cd, Mn, As, and Ni concentrations beyond the legal limit for drinking water. In contrast, some rivers have metal concentrations above the legal irrigation water limit. The majority of the rivers, particularly the peri-urban rivers in Dhaka city, Teesta, Korotoa, Rupsha, Karnaphuli, and Meghna Rivers, have significantly higher metal concentrations, according to sediment data. Metal concentrations in sediment are generally higher than USEPA standards in most rivers. Metal concentrations in fish and crops demonstrate metal bioaccumulation. The trend in metal concentration follows the order of water, fish, and sediment. It has been shown that crops irrigated with tainted water contain dangerous metals. The analysis of daily intake data on carcinogenic and noncarcinogenic substances reveals that consuming contaminated food can seriously impact human health.
اظهر المزيد [+] اقل [-]Environmental Flow Assessment (EFA) of Tawi River Discharge at the Jammu Location Using the Global Environmental Flow Calculator (GEFC) النص الكامل
2023
Maharshi Yadav, Govind Pandey and Pradeep Kumar
The water, food, and energy demands are the basic requirements of society. These demands are increasing daily due to an increase in population or lifestyle changes. To fulfill these ever-increasing demands, several water resource projects have come up which require the storage or diversion of river water. These interventions have caused widespread degradation of aquatic ecosystems. Due to the degradation of the aquatic ecosystem, several programs all around the globe began. In this series, Brisbane Declaration (2007) provided a more holistic definition of Environmental Flows (EFs) as the quantity, timing, duration, frequency, and quality of flows required to sustain freshwater, estuarine and near-shore ecosystems and the human livelihoods and well-being that depend on them. The present study was envisaged to assess for environmental flows of the Tawi river with a major objective of assessing the environmental flows of the Tawi river using the Global Environmental Flow Calculator developed by IWMI. The method provides E-Flows for different Environmental Management Classes. For the western Himalayan region, the river stretches in Environmental Management Class ‘B’ and ‘C’. The assessment provides E-Flows in two ways: (i) the percentage of Mean Annual Runoff and (ii) average monthly environmental flows. E-Flows were estimated as 42.34% to 56.96% of Mean Annual Runoff and varied from 5.73 cumecs during November to 68.23 during August.
اظهر المزيد [+] اقل [-]Visitors Perceptions of the Climate Comfort at the Padang Coastal Tourism Area, Indonesia النص الكامل
2023
N. Y. Sudiar and M. I. Gautama
This study explains visitors’ perceptions of climate comfort in the Padang coastal tourism area, including Air Manis Beach, Padang Beach, Nirwana Beach, and Pasir Jambak Beach. Climate comfort index calculation using the Holiday Climate Index (HCI) and survey methods are used to take data. The survey is conducted to collect data on climate comfort perception and the role of weather on that comfort. There are 409 respondents in this study. Most visitors state that weather affects climate comfort during their trip (99%) and need weather information for outdoor tourism (98.5%). However, only 27.1% are looking for weather information before traveling outdoors. This coastal tourism area’s perceived level of climate comfort is comfortable (64%). The thermal sensation is neutral (66%). Meanwhile, the average score of the comfort index in Padang is neutral throughout the year. The temperature interval indicates the comfortable category is between 26ºC-28ºC.
اظهر المزيد [+] اقل [-]Comparative Assessment and Monitoring Changes in NDVI of Achanakmar Tiger Reserve (ATR) and its Buffer Zone, India النص الكامل
2023
Anupama Mahato
Achanakmar Tiger Reserve (ATR), endowed with rich biological diversity and lush green vegetation in and around, makes it more unique. It is also an integral part of the Achanakmar Amarkantak Biosphere Reserve (AABR) and has been identified as one of the important tiger reserves of the Central Indian landscape due to its connectivity with other protected areas and tiger reserves in neighboring landscapes. Vegetation mapping and monitoring are important to understand changes in ecosystem processes and associated temporal and spatial impacts. Pre- and post-monsoon IRS, LISS III, and AWiFS satellite data from 2000, 2004, 2008, 2010, and 2013 were used for the present study. This paper is an attempt to examine the variation in the normalized difference vegetation index (NDVI) of ATR and its buffer zone on a seasonal and temporal basis. Climate conditions such as temperature, precipitation, relative humidity, etc. play an important role in the growth and development of healthy vegetation. The NDVI value of ATR has shown fluctuation and recorded positive growth over the past 14 years with few exceptions. The post-monsoon season recorded a higher NDVI value as compared to the pre-monsoon months. The maximum NDVI value was recorded in 2004 (+0.539) for the entire ATR and its buffer zone.
اظهر المزيد [+] اقل [-]Flood Mitigation and Pollution Abatement in Kaduna Metropolis Through Engineering Assessment and Analytical Hierarchy Process Design النص الكامل
2023
O. J. Oyebode and F. Paul
Pollution abatement and flood control activities require effective water resource planning, engineering assessment, sophisticated technology, and appropriate hydraulic structure designs. This paper x-rays flood mitigation and pollution abatement strategies that can be adopted in the Kaduna metropolis in Nigeria. Analytical hierarchy process of design, questionnaires, engineering assessment approach, and standard method for estimation of the runoff discharge was adopted for this research. Estimating water balance components and QSWAT Hydrological Model can be used with the QGIS interface for a greener environment. Suitable hydraulic systems were designed for long-term flood control in the River Kaduna catchment area through an analytic hierarchy Process. Statistical analysis, manning equations, and rational methods were utilized for adequate assessment and planning. The hydraulic discharge capacity of culverts, open channels, and other hydraulic structures was carefully checked. Flooding greatly impacts infrastructural development, and inadequate drainage systems contribute to it. Mitigation strategies, adequate water resource planning, and management will greatly benefit from addressing flood-related issues in the study area. This research provides information on the flood vulnerability of infrastructures and mitigation strategies that can be adopted in the study area. Viable policies and management strategies can be utilized to avert losses traceable to floods in developing and developed countries.
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