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النتائج 491 - 500 من 562
Process Intensification in Gas-Liquid Mass Transfer by the Introduction of Additives: A Review
2023
Huan Zhang, Bo Zheng, Ping Chang, Tao Yu and Chengtun Qu
To overcome the challenges of the increasing global energy and to solve the global energy & environment problems, process intensification is one way to develop new efficient production pathways for the chemical industry. Process intensification plays an important role in the gas-liquid mass transfer processes. This review provides an overview of the developments in gas-liquid mass transfer enhancement. A major enhancement method, namely introducing additives (including nanoparticles, oil, electrolyte, and surfactant) summarized and discussed here, includes the most recent accomplishments in gas-liquid mass transfer engineering. This review is expected to inspire new research for future developments and potential applications in scientific research and industry regarding gas-liquid mass transfer engineering. Finally, it presents conclusions and perspectives on enhancing gas-liquid mass transfer.
اظهر المزيد [+] اقل [-]Computer Vision Based Machine Learning and Deep Learning Approaches for Identification of Nutrient Deficiency in Crops: A Survey
2023
M. Sudhakar and R. M. Swarna Priya
Agriculture is a significant industry that plays a major role in a country’s sustainable environment and economic development. The global population demands increased food production with minimal losses. Nutrient deficiency is one of the major and crucial factors influencing crop production significantly. Common techniques for determining crop nutrition status are the diagnosis of plant morphology, Enzymology, chemical effects, fertilization, etc. However, the above techniques are invasive and time-consuming or infeasible while considering varied production practices in different locations, environments and climatic conditions. Computer Vision is an area of Computer Science that deals with creating Artificial Intelligence based vision systems that can use image data, process, and analyze as humans perform. Early Detection of Crop Nutrient deficiencies favors the farmers to monitor the affected crops and plan for the manure or fertilizer application, which supports to regain of the crop’s efficiency for attaining its maximum yield. Modern computer vision systems rely on Machine Learning (ML), Remote sensing, Satellite imagery, unmanned aerial vehicles (UAVs), Internet of things (IoT) based sensor devices, and Deep Learning (DL) models that use algorithms to extract required features from data. The objective of this work is to provide an overview of recent research and identify the scope of computer vision-based technologies used for identifying crop nutrient content and deficiency, find research challenges in predicting nutrient imbalance in comparison with plant diseases that show certain similar characteristics, thereby to improve crop health and production.
اظهر المزيد [+] اقل [-]Analysis of Laboratory Experimental Tests on Mixed Oil Disposal (Bilge) from Ships Based on Marpol Annex I: A Case Study of Port of Tanjung Mas Semarang and Port of Tegal
2023
S. Awel and A. R. Fuad
Management of marine pollution is a difficult condition to realize, especially the pollution of mixed oil disposal (bilge) resulting from the operation of ships. The oil component has different characteristics compared to the essence of other substances; namely, oil can float on the surface of the water because it has an extra weight the type/density of the essence. The parameters tested in this research are oil/fat content parameters and their extraction according to National Certification Institution 6989.59:2008. Bilge water samples were taken from five commercial ships that leaned on the port and then carried out pre-treatment and post-treatment tests with the liquid separation process in the Oil Water Separator (OWS) device on the ship and then tested in the laboratory to determine the infrared spectrum in the absorption of oil content emissions in water samples, which may not exceed the standard threshold for port water quality, i.e., 5 mg.L-1. The sampling tests were carried out for the variables temperature, pH, Total Dissolved Solid (TDS), and oil content obtained values were below the threshold for water quality. To find out the relationship between Group I and Group II, linear regression was used showing the Ho result in reject (0.000<0.05), which means there is a significant relationship between Group I and II.
اظهر المزيد [+] اقل [-]Recent Advances and Sustainable Approaches Towards Efficient Wastewater Treatment Using Natural Waste Derived Nanocomposites: A Review
2023
K. Haroon, J. Kherb, C. Jeyaseelan and M. Sen
Pollutants like arsenic, chromium, or other toxic heavy metals have the most dreadful impact on humans or animals and also become a threat worldwide. Introducing these contaminants into the environment is not just due to the chemical industry but also coexists in combined form in underground rocks, contaminating groundwater during breakdown. Epidemics are now largely blamed on toxic pollution in many different nations worldwide. The issue has gotten worse in underdeveloped nations, where metal contamination of the groundwater affects more than a million people. Different techniques are used to remove toxic pollutants from water, but most are expensive and energy intensive. Adsorption is preferable for removing contaminants such as heavy metals or chemical dyes. As nanomaterials have been demonstrated to be more effective as nanocomposites, we used an adsorbent of nanomaterial to use the adsorption approach. These materials have become more well-liked because of their useful applications and improved characteristics. Magnetic synthesized nanocomposites have magnetic properties, which become beneficial for adsorption as it enhances adsorption capacity. The insertion of the plant or aggregate waste material for nanocomposite synthesis inhibits the growth of bacteria or other microorganisms, preventing the material from getting infected if it is in the environment. In this review paper, we have focused on the green synthesis of nanomaterials used for water treatment.
اظهر المزيد [+] اقل [-]Study on the Adsorption Properties of Cr(VI) by Biochar with Different Treatments
2023
X. Zhang
The paper investigated the adsorption of Cr(VI) on biochar in simulated wastewater by static adsorption method, Fourier Transform Infrared spectra (FTIR), Raman, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscope (TEM) characterization analysis. The results show that biochar can effectively remove Cr(VI) in wastewater, and the adsorption equilibrium can be quickly reached within 100 min. The kinetic analysis shows that the quasi-second-order kinetic model can better fit the kinetic process of Cr(VI) adsorption by biochar, which shows that the main mechanism of the adsorption is the chemical bonding cooperation between Cr(VI) and the functional groups on the surface of biochar. Fit analysis of the isotherm at different temperatures shows that temperature increase promotes the adsorption of Cr(VI) on biochar, and thermodynamic analysis reveals that the adsorption of Cr(VI) on biochar is a spontaneous endothermic process. The Freundlich model effectively fits the adsorption isotherm of Cr(VI), indicating that the surface of biochar is uneven and Cr(VI) has undergone multilayer adsorption. The adsorption isotherm of Cr(VI) under the influence of HA and FA can be effectively fitted by the Freundlich model, and the adsorption efficiency is the highest when FA is added. The national analysis of Fourier Transform Infrared spectra (FTIR), Raman, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscope (TEM) further reveals the bond cooperation between Cr(VI) and the surface functional groups of biochar. The results show that biochar has potential application value in treating chrome-containing wastewater.
اظهر المزيد [+] اقل [-]Determination of the Dynamics of Thunderstorms Through the Dry Adiabatic Lapse Rate and Environmental Lapse Rate
2023
Shiemaa A. Hashim, Jasim H. Kadhum, Zainab M. Abbood, Osama T. Al-Taai and Wedyan G. Nassif
This research aims to determine the types of thunderstorms formed in the thickness of the cloud (determine the Dry adiabatic lapse rate (DALR) and Environmental lapse rate (ELR)) in the case of precipitation during the day. Data were taken by Temperature, Dew point, Atmospheric Pressure, and Height from re-analysis by the (ECMWF) for the heights (0-18000) m, the levels of pressure (1000-100) mbar, low cloud cover data, and the characteristic days ((18, 24, 27) February, 28 April, and 25 November) of the year 2018 for Baghdad station were chosen to obtain the largest possible number of clouds and their diversity to use them in calculating the cloud cover and weather stability in terms of calculating the daily change, temperature, dew point in addition to calculating the low cloud cover with altitude and atmospheric instability. The Sigma Plot program was used in this research to determine the base of clouds and thunderstorms. The change in temperature, Dew point, clouds base, and altitude was determined, then the cloud thickness, types, and classification were calculated. The clouds found are strong thunderstorm clouds characterized by thickness and height, such as the clouds of Nimbostratus (Ns) and Cumulonimbus (Cb).
اظهر المزيد [+] اقل [-]Sustainable Alternative Materials to Concrete Masonry Partition Walls: Light-Weight Wall Panel Using Polymethyl Methacrylate (PMMA) and Shredded Waste Metalized Film Packaging
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 [-]Perception Versus Actual Value of Quality of Drinking Water: A Case Study of Iron and Steel Industry in West Bengal, India
2023
Rahul Rajak, Arup Jana, Aparajita Chattopadhyay, Sushmita Singh and Jitender Prasad
The study aims to understand employees’ knowledge, awareness, and overall perception of drinking water quality in the Iron and Steel Industry in Burnpur, India. Further, this study evaluated drinking water’s physicochemical and bacteriological properties collected from different company sites. This study uses a mixed-method approach with individual interviews of selected employees (n=342) and the laboratory test of eight selected drinking water sites. The results show that most employees considered drinking water acceptable to be excellent. However, only 30% of employees in Site 1 (Coke Oven By-Product department) have reported organoleptic properties of water under the excellent category. The result explained that other physicochemical and bacteriological properties are in good status in all sites except for a colony count, expressing their suitability for drinking purposes. In summary, employees’ perception of water quality aligns with their drinking water’s physicochemical and bacteriological properties.
اظهر المزيد [+] اقل [-]Characteristics of Nickel Laterite Mine Waste in Caraga Region, Philippines and Its Potential Utilization
2023
Abigael Balbin, Jobelle Capilitan, Evelyn Taboada and Ian Dominic Tabañag
Nickel laterite mining is one of the sources of nickel-iron material used for producing steel and various materials. This mining activity leaves waste in the mine, including rocks, overburden, silt, and dust. Characterization is an important primary step in understanding waste for proper management, utilization, and disposal. The pH, organic matter, and elemental composition are analyzed in this study. The pH of nickel laterite mine waste is neutral to moderately alkaline, which makes it unlikely to cause acid mine drainage, which is one of the most prevailing environmental problems of mines. The organic matter content also showed favorable results for plant growth. However, the macronutrients necessary for the plant are too high, making it less favorable for agricultural utilization. Elemental composition shows the presence of nickel and other elements lower than the economically acceptable level. However, processing the lower grade can be the best option when all higher-grade resources are exhausted. The nickel laterite mine waste can be reused to further extract the metals when sources of higher grades are depleted, repurposed such as in the production of bricks and ceramics, or mined-out mines can be repurposed for renewable energy sources such as solar and wind farms.
اظهر المزيد [+] اقل [-]Recycling Practices of E-Waste and Associated Challenges: A Research Trends Analysis
2023
Jit Das and Arpita Ghosh
In this fast-moving world, we use many electronic items daily to fulfill our daily work. Also, in the fast-growing economy, electronic items play key roles. India’s e-waste is projected to be around 18 lakh metric tons. According to industry sources, electronic trash will climb to almost 50 lakh metric tons in the next three years. According to government sources, only ten percent of electronic waste is gathered. These electronic items and batteries contain many heavy metals that are hazardous to humanity’s and the environment’s health. These heavy metals should be retrieved from the disposed of e-waste, so the resource can be reused or recycled, rather than continuously extracting heavy metals from the earth’s crust. In 2015, The “Initiative on Environmental Threats of Electronic Waste” was introduced by the Ministry of Electronics and Information Technology (MeitY). This project is part of the Indian government’s ‘Digital India’ strategy. There is an immediate need to implement green supply chain management and resource recovery from electronics waste so that circular material management (SDG 12) & sustainability can be achieved. This article demonstrates the problems and presents E-Waste recycling procedures, Life cycle assessment of E-waste, and EPR practices, along with potential areas for improvement. The bibliometric analysis was performed using R-studio biblioshiny tools for the last 53 years and 1243 published articles to understand the research trends.
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