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•CO2 was used as an inexpensive feedstock for various fuels and chemicals production.•Explained various utilization approaches and their mechanisms for CO2 mitigation.•Discussed the ...various CO2 conversion processes.•Current status and Scope for further research on CO2 conversion has been discussed.
Carbon dioxide (CO2) is a odourless and colourless gas which plays a noteworthy role in the climate and weather changes. Different natural and anthropogenic activities induces CO2 emission in the environment. Though CO2 causes global warming, it acts as an essential element for photosynthesis process in plants. CO2 can also be used as an inexpensive feedstock for the production of various fuels and chemicals. Many approaches like electrochemical, thermal, biochemical, chemo-enzymatic and photocatalytic methods are available by means of which the harmful CO2 is captured from the environment. Similarly, via different chemical, physical and biological processes, it can be converted into useful products like fuels and chemicals. This review mainly focuses on various utilization approaches and their mechanisms for CO2 mitigation. In addition, CO2 conversion processes like hydrogenation, esterification, methanation, reforming, and reverse water-gas shift (RWGS) reactions, their mechanisms and their current status along with future perspectives were comprehensively discussed.
The increase in the usage of internet and social media has enabled people exchange views, opinions and thoughts as never before. This exchange of data has paved the way for sentiment analysis. The ...basic task of sentiment analysis is to classify the data into positive, negative and neutral. In this paper an effective MapReduce-Based Hybrid NBC-TFIDF (Naive Bayes Classifier -Term Frequency Inverse Document Frequency) algorithm is proposed to mine people sentiment. A Map Reduce-Based Hybrid NBC is employed to classify the data based on the polarity score of each sentence in social media data. The polarity score is calculated using the emotion corpus and the Diabetic corpus is created using food Glycemic Index and physical activity index. This study analyses the correlation of food habits, physical activity and diabetic risk factors among Indian population using social network data. Around two million data has been identified for the study and the study is restricted to India. The experimental result shows that MapReduce-Based Hybrid NBC–TFIDF performs efficiently in multimode cluster. The results reveal that no individual factor is associated with diabetic risk and also a group of common factors contribute to diabetes mellitus. It is found that 60% of the social media data had positive polarity about the food items that are high in Glycemic Index which is the main root cause for type – 2 Diabetes. This Big-Data analysis reveals that the young generations of India are unaware of risk factors of Diabetes mellitus.
Africa's history and ecology were shaped by colonization. The European invasion of eastern nations had a significant influence on the environment. The technical advancements due to colonization have ...been both beneficial and detrimental to the colonized countries. The harmful consequences have prompted several researchers and African writers to conduct a critical examination of the interaction between humans and their environment in terms of race, culture, economy, power, and belonging. Ben Okri is an internationally acclaimed poet, writer, artist, and public speaker. In his trilogies The Famished Road, Songs of Enchantment, and Infinite Riches Okri has depicted the repercussions of colonization and the process of decolonization on the individual and the environment in order to understand the African reality. This paper highlights the interconnection of nature and culture which is considered as one of the main tenets of African culture and tradition. Okri employs magical realism as a literary method to emphasize the interplay between the human and natural worlds. Okri has included vivid imagery of verdant forest that has been deforested and wounded. According to the Yoruba mythology, the forest is frequently associated with magic and the supernatural world, in keeping with West African customs. Therefore, the exploitation of the natural world has led to the abandonment of traditional values which is well depicted. Further, the paper attempts to examine the effect of colonialism in eroding the spirit world and the physical world in terms of social structure and the degrading culture and its relationship with the environment.
In today’s world, carbon-based materials research is much wider wherein, it requires a lot of processing techniques to manufacture or synthesize. Moreover, the processing methods through which the ...carbon-based materials are derived from synthetic sources are of high cost. Processing of such hierarchical porous carbon materials (PCMs) was slightly complex and only very few methods render carbon nano-materials (CNMs) with high specific surface area. Once it is processed, which paves a path to versatile applications. CNMs derived from biological sources are widespread and their application spectrum is also very wide. This review focuses on biomass-derived CNMs from various plant sources for its versatile applications. The major thrust areas of energy storage include batteries, super-capacitors, and fuel cells which are described in this article. Meanwhile, the challenges faced during the processing of biomass-derived CNMs and their future prospects are also discussed comprehensively.
Manufacturing of fiber reinforced polymer matrix composite materials is being done with various methods in recent days. But controlling the accuracy of manufacturing and begetting quality products is ...very challenging. Adopting single manufacturing techniques may not cater this purpose, but blended or unified technologies do. Artificial intelligence (AI) is an emerging technique that is highly reliable to be blended with current methods and caters to the needs of various composite manufacturers to the maximum possible extent. Accordingly, in this article, the primary focus is provided on the manufacturing sector and more particularly emphasis only on composite material manufacturing with the help of AI. The way the manufacturing is guided by digital technologies including AI is effective in terms of the quality of manufacturing composite materials. In most of the recent studies, AI techniques are used in autoclave manufacturing of composites to control temperature and pressure, curing of composites establishing control over the curing environment and also in flaw detection of composites. This article also focuses on using digital technologies for manufacturing simulation, hybridizing digital technologies and a few of its implications over Industry 4.0.
Increasing global environmental problems and awareness towards the utilization of eco-friendly resources enhanced the progress of research towards the development of next-generation biodegradable and ...environmentally friendly material. The development of natural-based composite material has led to various advantages such as a reduction in greenhouse gases and carbon footprints. In spite of the various advantages obtained from green materials, there are also a few disadvantages, such as poor interfacial compatibility between the polymer matrix and natural reinforcements and the high hydrophilicity of composites due to the reinforcement of hydrophilic natural fibers. This review focuses on various moisture-absorbing and sound-absorbing natural fiber polymer composites along with the synopsis of preparation methods of natural fiber polymer composites. It was stated in various studies that natural fibers are durable with a long life but their moisture absorption behavior depends on various factors. Such natural fibers possess different moisture absorption behavior rates and different moisture absorption behavior. The conversion of hydrophilic fibers into hydrophobic is deemed very important in improving the mechanical, thermal, and physical properties of the natural-fiber-reinforced polymer composites. One more physical property that requires the involvement of natural fibers in place of synthetic fibers is the sound absorption behavior. Various researchers have made experiments using natural-fiber-reinforced polymer composites as sound-absorbing materials. It was found from various studies that composites with higher thickness, porosity, and density behaved as better sound-absorbing materials.
Composite materials have become inevitable in many current day engineering applications. Aluminium alloy based composites were used in numerous fields of engineering and technology owing to their ...enormous advantages including low processing cost and broader scope of application. Developing a sustainable bio composite has become the order of the day to mitigate associated environmental issues. In line with this, current experimental work aims to develop a seashell powder reinforced aluminium alloy 2219 composites and determine their mechanical and tribological behaviour. Composites were fabricated using conventional casting with 1, 2 and 3% by weight of seashell powder in aluminium alloy matrix. Chemical constituents present in seashell powder were determined by using X-ray Diffraction studies. Cast composites were subjected to energy dispersive X-ray spectroscopy to witness the formation of any secondary elements. Influence of seashell powder content over hardness and tribological behaviour of aluminium alloy 2219 composites were analysed by conducting appropriate experiments. Hardness was found to be maximum for the composite containing 3% of seashell powder. Tribological behaviour of the composites were optimized using response surface methodology. Wear and frictional resistance of the composites increased with the content of seashell powders and it was the most influential factor according to optimization results. Surface morphology was examined through scanning electron microscopic technique to know the influence of seashell powder on the wear behaviour of the composites and the type of wear occurred.
Plants naturally cycle amino acids across root cell plasma membranes, and any net efflux is termed exudation. The dominant ecological view is that microorganisms and roots passively compete for amino ...acids in the soil solution, yet the innate capacity of roots to recover amino acids present in ecologically relevant concentrations is unknown. We find that, in the absence of culturable microorganisms, the influx rates of 16 amino acids (each supplied at 2.5 micromolar) exceed efflux rates by 5% to 545% in roots of alfalfa (Medicago sativa), Medicago truncatula, maize (Zea mays), and wheat (Triticum aestivum). Several microbial products, which are produced by common soil microorganisms such as Pseudomonas bacteria and Fusarium fungi, significantly enhanced the net efflux (i.e. exudation) of amino acids from roots of these four plant species. In alfalfa, treating roots with 200 micromolar phenazine, 2,4-diacetylphloroglucinol, or zearalenone increased total net efflux of 16 amino acids 200% to 2,600% in 3 h. Data from 15N tests suggest that 2,4-diacetylphloroglucinol blocks amino acid uptake, whereas zearalenone enhances efflux. Thus, amino acid exudation under normal conditions is a phenomenon that probably reflects both active manipulation and passive uptake by microorganisms, as well as diffusion and adsorption to soil, all of which help overcome the innate capacity of plant roots to reabsorb amino acids. The importance of identifying potential enhancers of root exudation lies in understanding that such compounds may represent regulatory linkages between the larger soil food web and the internal carbon metabolism of the plant.
Current work attempts to fabricate aluminium alloy AA2219 metal matrix composite (AMC) reinforced with natural bio-based sea shell powder (SSP) which is a ceramic material, in view of improving the ...mechanical and tribological properties. SSP was characterized by X-Ray Diffraction (XRD) to assess its chemical constituents and particle size. Stir casting route was adopted for fabricating AMCs reinforced with 1, 2 and 3 wt. % of SSP. Energy Dispersive X-ray Spectroscopy (EDS) was used to analyse the formation of secondary elements during casting and scanning electron microscopy (SEM) was used analyze the surface morphology of the composite specimen before and after tribological tests. Hardness, Compressive strength and tribological properties were evaluated using appropriate tests and corresponding ASTM standards. Characterization methods revealed that the formation of secondary elements was very low at 3 wt. % of SSP when compared with other compositions. Hardness and compressive strength was found to be maximum for 3 wt. % of SSP while the specific wear rate and coefficient of friction values were found to be lesser for the same composite when compared with the unreinforced alloy and were on par with the AA2219 composites containing synthetic reinforcements.
Abstract
Due to population growth and economic development, the water shortage in many urban cities has become a serious concern for sustainability and management. In-house surveys and in-person ...monitoring of water consumption is a tedious task. To overcome this difficulty Geographic Information System helps in finding the optimal solution. The study on existing literature outlines the major underlying issues and challenges in analyzing water consumption patterns. The objective of this work is to identify urban water consumption patterns and ways to provide a surplus supply of water using geographic Information. The results reveal that the urban areas with a high economy consume more water than the low-income group. As a feasible solution, a simple water decision support system is proposed with the help of GIS to overcome the upcoming challenges.
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