Search results for: natural stone
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5822

Search results for: natural stone

1562 Degradation of Petroleum Hydrocarbons Using Pseudomonas Aeruginosa Isolated from Oil Contaminated Soil Incorporated into E. coli DH5α Host

Authors: C. S. Jeba Samuel

Abstract:

Soil, especially from oil field has posed a great hazard for terrestrial and marine ecosystems. The traditional treatment of oil contaminated soil cannot degrade the crude oil completely. So far, biodegradation proves to be an efficient method. During biodegradation, crude oil is used as the carbon source and addition of nitrogenous compounds increases the microbial growth, resulting in the effective breakdown of crude oil components to low molecular weight components. The present study was carried out to evaluate the biodegradation of crude oil by hydrocarbon-degrading microorganism Pseudomonas aeruginosa isolated from natural environment like oil contaminated soil. Pseudomonas aeruginosa, an oil degrading microorganism also called as hydrocarbon utilizing microorganism (or “HUM” bug) can utilize crude oil as sole carbon source. In this study, the biodegradation of crude oil was conducted with modified mineral basal salt medium and nitrogen sources so as to increase the degradation. The efficacy of the plasmid from the isolated strain was incorporated into E.coli DH5 α host to speed up the degradation of oil. The usage of molecular techniques has increased oil degradation which was confirmed by the degradation of aromatic and aliphatic rings of hydrocarbons and was inferred by the lesser number of peaks in Fourier Transform Infrared Spectroscopy (FTIR). The gas chromatogram again confirms better degradation by transformed cells by the lesser number of components obtained in the oil treated with transformed cells. This study demonstrated the technical feasibility of using direct inoculation of transformed cells onto the oil contaminated region thereby leading to the achievement of better oil degradation in a shorter time than the degradation caused by the wild strain.

Keywords: biodegradation, aromatic rings, plasmid, hydrocarbon, Fourier Transform Infrared Spectroscopy (FTIR)

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1561 Ultrathin NaA Zeolite Membrane in Solvent Recovery: Preparation and Application

Authors: Eng Toon Saw, Kun Liang Ang, Wei He, Xuecheng Dong, Seeram Ramakrishna

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Solvent recovery process is receiving utmost attention in recent year due to the scarcity of natural resource and consciousness of circular economy in chemical and pharmaceutical manufacturing process. Solvent dehydration process is one of the important process to recover and to purify the solvent for reuse. Due to the complexity of solvent waste or wastewater effluent produced in pharmaceutical industry resulting the wastewater treatment process become complicated, thus an alternative solution is to recover the valuable solvent in solvent waste. To treat solvent waste and to upgrade solvent purity, membrane pervaporation process is shown to be a promising technology due to the energy intensive and low footprint advantages. Ceramic membrane is adopted as solvent dehydration membrane owing to the chemical and thermal stability properties as compared to polymeric membrane. NaA zeolite membrane is generally used as solvent dehydration process because of its narrow and distinct pore size and high hydrophilicity. NaA zeolite membrane has been mainly applied in alcohol dehydration in fermentation process. At this stage, the membrane performance exhibits high separation factor with low flux using tubular ceramic membrane. Thus, defect free and ultrathin NaA membrane should be developed to increase water flux. Herein, we report a simple preparation protocol to prepare ultrathin NaA zeolite membrane supported on tubular ceramic membrane by controlling the seed size synthesis, seeding methods and conditions, ceramic substrate surface pore size selection and secondary growth conditions. The microstructure and morphology of NaA zeolite membrane will be examined and reported. Moreover, the membrane separation performance and stability will also be reported in isopropanol dehydration, ketone dehydration and ester dehydration particularly for the application in pharmaceutical industry.

Keywords: ceramic membrane, NaA zeolite, pharmaceutical industry, solvent recovery

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1560 Isolation and Characterisation of Novel Environmental Bacteriophages Which Target the Escherichia coli Lamb Outer Membrane Protein

Authors: Ziyue Zeng

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Bacteriophages are viruses which infect bacteria specifically. Over the past decades, phage λ has been extensively studied, especially its interaction with the Escherichia coli LamB (EcLamB) protein receptor. Nonetheless, despite the enormous numbers and near-ubiquity of environmental phages, aside from phage λ, there is a paucity of information on other phages which target EcLamB as a receptor. In this study, to answer the question of whether there are other EcLamB-targeting phages in the natural environment, a simple and convenient method was developed and used for isolating environmental phages which target a particular surface structure of a particular bacterium; in this case, the EcLamB outer membrane protein. From the enrichments with the engineered bacterial hosts, a collection of EcLamB-targeting phages (ΦZZ phages) were easily isolated. Intriguingly, unlike phage λ, an obligate EcLamB-dependent phage in the Siphoviridae family, the newly isolated ΦZZ phages alternatively recognised EcLamB or E. coli OmpC (EcOmpC) as a receptor when infecting E. coli. Furthermore, ΦZZ phages were suggested to represent new species in the Tequatrovirus genus in the Myoviridae family, based on phage morphology and genomic sequences. Most phages are thought to have a narrow host range due to their exquisite specificity in receptor recognition. With the ability to optionally recognise two receptors, ΦZZ phages were considered relatively promiscuous. Via the heterologous expression of EcLamB on the bacterial cell surface, the host range of ΦZZ phages was further extended to three different enterobacterial genera. Besides, an interesting selection of evolved phage mutants with a broader host range was isolated, and the key mutations involved in their evolution to adapt to new hosts were investigated by genomic analysis. Finally, and importantly, two ΦZZ phages were found to be putative generalised transducers, which could be exploited as tools for DNA manipulations.

Keywords: environmental microbiology, phage, microbe-host interactions, microbial ecology

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1559 A Comparative Study on the Phenolics Composition and Antioxidant Properties of Water Yam Landraces in Kerala, India

Authors: Anumol Jose, Sajana Nazar, M. R. Vishnu, M. Anilkumar

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Water yam is an underutilized tropical tuber crop and a rich source of polyphenol compounds and acylated anthocyanins. There is an inverse relationship between the risk of chronic human diseases and the consumption of polyphenolic rich diet. Dioscorea alata is a plant species with several undocumented landraces. In this study, several landraces of water yam with distinct morphological features were collected from all over kerala. Distinct variation in morphological feature among landraces was tuber colour and only those landraces which expressed consistent morphological characters for constitutively two growing seasons were included in the study. Plants were categorized according to the L*a*b* colour attributes of tuber extracts. There were five categories, red, pink, orange, yellow and white. Total phenol, flavanoid and anthocyanin content of the tuber extracts were measured spectroscopically and correlated with antioxidant properties determined by 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical method and ferric reducing antioxidant power assay. Landraces showed statistically significant difference in all the parameters studied and strong correlation were observed between total phenol and antioxidant activity. Out of the five categories orange coloured tubers showed relatively high phenol and flavanoid content.Colour variations of tuber extracts correlated with anthocyanin quantity and polymeric nature of anthocyanins. This study helps to identify and categorize landraces of D.alata with potential health benefits and commercial applications. Distinct colour characteristics of tuber could be useful in the field of natural colorants. This study also aimed to document and preserve landraces of water yams for further study and research in this area.

Keywords: the antioxidant property, anthocyanins, polyphenols, water yam

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1558 Survival and Retention of the Probiotic Properties of Bacillus sp. Strains under Marine Stress Starvation Conditions and Their Potential Use as a Probiotic for Aquaculture Objectives

Authors: Abdelkarim Mahdhi, Fdhila Kais, Faouzi Lamari, Zeineb Hmila, Fathi Kamoun, Maria Ángeles Esteban, Amina Bakhrouf

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Aquaculture is the world’s fastest growing food-production sector. However, one of the most serious problems regarding the culture of marine fishes is the mortality associated with pathogenic bacteria that occurs in the critical phases of larval development. Conventional approaches, such as the use of antimicrobial drugs to control diseases, have had limited success in the prevention or cure of aquatic diseases. Promising alternatives to antibiotics are probiotics, which are food supplements consisting of live microorganisms that benefit the host organism. In the search for more effective and environmentally friendly treatments with probionts against pathogenic species in shrimp larval culture, the probiotic properties of Bacillus strains isolated from Artemia culture such as antibacterial activity, adhesion, pathogenicity, toxicity and the effect of marine stress on viability and survival were investigated, as well as the changes occurring in their properties. Analyses showed that these bacteria corresponded to the genus Bacillus sp. Antagonism and adherence assays revealed that these strains have an inhibitory effect against pathogenic bacteria in vitro and in vivo conditions and are fairly adherent. Challenge tests performed with Artemia larvae provided evidence that the tested Bacillus strains were neither pathogenic nor toxic to the host. The tested strains maintained their viability and their probiotic properties during the period of study. The results suggest that the tested strains have suffered changes allowing them to survive in seawater in the absence of nutrients and outside their natural host, identifying them as potential probiotic candidates for Artemia culture.

Keywords: bacillus, probiotic, cell viability, stress response

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1557 Emerging Therapeutic Approach with Dandelion Phytochemicals in Breast Cancer Treatment

Authors: Angel Champion, Sadia Kanwal, Rafat Siddiqui

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Harnessing phytochemicals from plant sources presents a novel opportunity to prevent or treat malignant diseases, including breast cancer. Chemotherapy lacks precision in targeting cancerous cells while sparing normal cells, but a phytopharmaceutical approach may offer a solution. Dandelion, a common weed plant, is rich in phytochemicals and provides a safer, more cost-effective alternative with lower toxicity than traditional pharmaceuticals for conditions such as breast cancer. In this study, an in-vitro experiment will be conducted using the ethanol extract of Dandelion on triple-negative MDA-231 breast cancer cell lines. The polyphenolic analysis revealed that the Dandelion extract, particularly from the root and leaf (both cut and sifted), had the most potent antioxidant properties and exhibited the most potent antioxidation activity from the powdered leaf extract. The extract exhibits prospective promising effects for inducing cell proliferation and apoptosis in breast cancer cells, highlighting its potential for targeted therapeutic interventions. Standardizing methods for Dandelion use is crucial for future clinical applications in cancer treatment. Combining plant-derived compounds with cancer nanotechnology holds the potential for effective strategies in battling malignant diseases. Utilizing liposomes as carriers for phytoconstituent anti-cancer agents offers improved solubility, bioavailability, immunoregulatory effects, advancing anticancer immune function, and reducing toxicity. This integrated approach of natural products and nanotechnology has significant potential to revolutionize healthcare globally, especially in underserved communities where herbal medicine is prevalent.

Keywords: apoptosis, antioxidant activity, cancer nanotechnology, phytopharmaceutical

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1556 Process Development for the Conversion of Organic Waste into Valuable Products

Authors: Ife O. Bolaji

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Environmental concerns arising from the use of fossil fuels has increased the interest in the development of renewable and sustainable sources of energy. This would minimize the dependence on fossil fuels and serve as future alternatives. Organic wastes contain carbohydrates, proteins and lipids, which can be utilised as carbon sources for the production of bio-based products. Cellulose is the most abundant natural biopolymer, being the main structural component of lignocellulosic materials. The aim of this project is to develop a biological process for the hydrolysis and fermentation of organic wastes into ethanol and organic acids. The hydrolysis and fermentation processes are integrated in a single vessel using undefined mixed culture microorganisms. The anaerobic fermentation of microcrystalline cellulose was investigated in continuous and batch reactors at 25°C with an appropriate growth medium for cellulase formation, hydrolysis, and fermentation. The reactors were inoculated with soil (B1, C1, C3) or sludge from an anaerobic digester (B2, C2) and the breakdown of cellulose was monitored by measuring the production of ethanol, organic acids and the residual cellulose. The batch reactors B1 and B2 showed negligible microbial activity due to inhibition while the continuous reactors, C1, C2 and C3, exhibited little cellulose hydrolysis which was concealed by the cellulose accumulation in the reactor. At the end of the continuous operation, the reactors C1, C2 and C3 were operated under batch conditions. 48%, 34% and 42% cellulose had been fermented by day 88, 55 and 55 respectively of the batch fermentation. Acetic acid, ethanol, propionic acid and butyric acids were the main fermentation products in the reactors. A stable concentration of 0.6 g/l ethanol and 5 g/L acetic acid was maintained in C3 for several weeks due to reduced activity of methanogens caused by the decrease in pH. Thus far, the results have demonstrated that mixed microbial culture is capable of hydrolysing and fermenting cellulose under lenient conditions. The fermentation of cellulose has been found effective in a combination of continuous and batch processes.

Keywords: cellulose, hydrolysis, mixed culture, organic waste

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1555 A Hybrid Multi-Criteria Hotel Recommender System Using Explicit and Implicit Feedbacks

Authors: Ashkan Ebadi, Adam Krzyzak

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Recommender systems, also known as recommender engines, have become an important research area and are now being applied in various fields. In addition, the techniques behind the recommender systems have been improved over the time. In general, such systems help users to find their required products or services (e.g. books, music) through analyzing and aggregating other users’ activities and behavior, mainly in form of reviews, and making the best recommendations. The recommendations can facilitate user’s decision making process. Despite the wide literature on the topic, using multiple data sources of different types as the input has not been widely studied. Recommender systems can benefit from the high availability of digital data to collect the input data of different types which implicitly or explicitly help the system to improve its accuracy. Moreover, most of the existing research in this area is based on single rating measures in which a single rating is used to link users to items. This paper proposes a highly accurate hotel recommender system, implemented in various layers. Using multi-aspect rating system and benefitting from large-scale data of different types, the recommender system suggests hotels that are personalized and tailored for the given user. The system employs natural language processing and topic modelling techniques to assess the sentiment of the users’ reviews and extract implicit features. The entire recommender engine contains multiple sub-systems, namely users clustering, matrix factorization module, and hybrid recommender system. Each sub-system contributes to the final composite set of recommendations through covering a specific aspect of the problem. The accuracy of the proposed recommender system has been tested intensively where the results confirm the high performance of the system.

Keywords: tourism, hotel recommender system, hybrid, implicit features

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1554 Chemically Modified Chitosan Derivatives with Ameliorated Properties Appropriate for Drug Delivery

Authors: Georgia M. Michailidou, Nina-Maria S. Ainali, Eleftheria C. Xanthopoulou, Dimitrios N. Bikiaris

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Polysaccharides are polymeric materials derived from nature. They are extensively used in pharmaceutical technology due to their low cost, their ready availability and their low toxicity. Chitosan is the product derived from the deacetylation of chitin usually obtained from arthropods. It is a linear polysaccharide which is composed of repeated units of N-deacetylated amino groups and some N-acetylated groups residues. Due to its excellent biological properties, it is an attractive natural polymer. It is biocompatible with low toxicity and complete biodegradability. Although it has excellent properties, the chemical modification of its structure results in new derivatives with ameliorated and more improved properties compared to the initial polymer. This is the exact purpose of the present study in which chitosan was modified with three different monomers, namely trans-aconitic acid, succinic anhydride and 2-hydroxyethyl acrylate. In chitosan’s modification with trans aconitic acid, EDC was utilized as an activator of the carboxylic groups of the monomer, and then a coupling reaction with the amino groups took place. Succinic anhydride reacted with chitosan through a ring opening reaction while 2-hydroxyethyl acrylate reacted through the addition of chitosan’s amino group to the double bond of the monomer. Through FTIR and NMR measurements the success of each reaction was confirmed, and the new structures of the derivatives were verified. X-ray diffraction was utilized in order to examine the effect of the modifications in chitosan’s crystallinity. Finally, swelling tests were conducted in order to assess the improved ability of the new polymeric materials to absorb water. Our results support the successful modification of chitosan’s macromolecular chains in all three reactions. Furthermore, the new derivatives appear to be amorphous concerning their crystallinity and have great ability in absorbing water.

Keywords: chitosan, derivatives, modification, polysaccharide

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1553 An Analysis on Clustering Based Gene Selection and Classification for Gene Expression Data

Authors: K. Sathishkumar, V. Thiagarasu

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Due to recent advances in DNA microarray technology, it is now feasible to obtain gene expression profiles of tissue samples at relatively low costs. Many scientists around the world use the advantage of this gene profiling to characterize complex biological circumstances and diseases. Microarray techniques that are used in genome-wide gene expression and genome mutation analysis help scientists and physicians in understanding of the pathophysiological mechanisms, in diagnoses and prognoses, and choosing treatment plans. DNA microarray technology has now made it possible to simultaneously monitor the expression levels of thousands of genes during important biological processes and across collections of related samples. Elucidating the patterns hidden in gene expression data offers a tremendous opportunity for an enhanced understanding of functional genomics. However, the large number of genes and the complexity of biological networks greatly increase the challenges of comprehending and interpreting the resulting mass of data, which often consists of millions of measurements. A first step toward addressing this challenge is the use of clustering techniques, which is essential in the data mining process to reveal natural structures and identify interesting patterns in the underlying data. This work presents an analysis of several clustering algorithms proposed to deals with the gene expression data effectively. The existing clustering algorithms like Support Vector Machine (SVM), K-means algorithm and evolutionary algorithm etc. are analyzed thoroughly to identify the advantages and limitations. The performance evaluation of the existing algorithms is carried out to determine the best approach. In order to improve the classification performance of the best approach in terms of Accuracy, Convergence Behavior and processing time, a hybrid clustering based optimization approach has been proposed.

Keywords: microarray technology, gene expression data, clustering, gene Selection

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1552 Schedule Risk Management for Complex Projects: The Royal Research Ship: Sir David Attenborough Case Study

Authors: Chatelier Charlene, Oyegoke Adekunle, Ajayi Saheed, Jeffries Andrew

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This study seeks to understand Schedule Risk Assessments as a priori for better performance whilst exploring the strategies employed to deliver complex projects like the New Polar research ship. This high-profile vessel was offered to Natural Environment Research Council and British Antarctic Survey (BAS) by Cammell Laird Shipbuilders. The Research Ship was designed to support science in extreme environments, with the expectancy to provide a wide range of specialist scientific facilities, instruments, and laboratories to conduct research over multiple disciplines. Aim: The focus is to understand the allocation and management of schedule risk on such a Major Project. Hypothesising that "effective management of schedule risk management" could be the most critical factor in determining whether the intended benefits mentioned are delivered within time and cost constraints. Objective 1: Firstly, the study seeks to understand the allocation and management of schedule risk in Major Projects. Objective 2: Secondly, it explores "effective management of schedule risk management" as the most critical factor determining the delivery of intended benefits. Methodology: This study takes a retrospective review of schedule risk management and how it influences project performance using a case study approach for the RRS (Royal Research Ship) Sir David Attenborough. Research Contribution: The outcomes of this study will contribute to a better understanding of project performance whilst building on its under-researched relationship to schedule risk management for complex projects. The outcomes of this paper will guide further research on project performance and enable the understanding of how risk-based estimates over time impact the overall risk management of the project.

Keywords: complexity, major projects, performance management, schedule risk management, uncertainty

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1551 Waters Colloidal Phase Extraction and Preconcentration: Method Comparison

Authors: Emmanuelle Maria, Pierre Crançon, Gaëtane Lespes

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Colloids are ubiquitous in the environment and are known to play a major role in enhancing the transport of trace elements, thus being an important vector for contaminants dispersion. Colloids study and characterization are necessary to improve our understanding of the fate of pollutants in the environment. However, in stream water and groundwater, colloids are often very poorly concentrated. It is therefore necessary to pre-concentrate colloids in order to get enough material for analysis, while preserving their initial structure. Many techniques are used to extract and/or pre-concentrate the colloidal phase from bulk aqueous phase, but yet there is neither reference method nor estimation of the impact of these different techniques on the colloids structure, as well as the bias introduced by the separation method. In the present work, we have tested and compared several methods of colloidal phase extraction/pre-concentration, and their impact on colloids properties, particularly their size distribution and their elementary composition. Ultrafiltration methods (frontal, tangential and centrifugal) have been considered since they are widely used for the extraction of colloids in natural waters. To compare these methods, a ‘synthetic groundwater’ was used as a reference. The size distribution (obtained by Field-Flow Fractionation (FFF)) and the chemical composition of the colloidal phase (obtained by Inductively Coupled Plasma Mass Spectrometry (ICPMS) and Total Organic Carbon analysis (TOC)) were chosen as comparison factors. In this way, it is possible to estimate the pre-concentration impact on the colloidal phase preservation. It appears that some of these methods preserve in a more efficient manner the colloidal phase composition while others are easier/faster to use. The choice of the extraction/pre-concentration method is therefore a compromise between efficiency (including speed and ease of use) and impact on the structural and chemical composition of the colloidal phase. In perspective, the use of these methods should enhance the consideration of colloidal phase in the transport of pollutants in environmental assessment studies and forensics.

Keywords: chemical composition, colloids, extraction, preconcentration methods, size distribution

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1550 Curcumin Derivatives as Potent Inhibitors of Inducible Nitric Oxide Synthase in Osteoarthritis: A Molecular Docking Study

Authors: F. Ambreen, A.Naheed

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Osteoarthritis (OA) is a degenerative disorder affecting millions of people worldwide. Nitric oxide (NO) was found to play a catabolic role in the development of osteoarthritis. It is a toxic free radical gas generated during the metabolism of L-arginine by the enzyme Nitric oxide synthase (NOS). Inducible Nitric Oxide Synthase (iNOS) is one of the isoform of NOS, and its overexpression leads to the excessive formation of NO that results in pathophysiological joint conditions. Several synthetic anti-inflammatory drugs and inhibitors are present to date, but all showed side effects and complications. Therefore, the pursuit of natural disease-modifying drugs remains a top priority. Curcumin is an active component of turmeric, and the past few decades have witnessed intense research devoted to the antioxidant and anti-inflammatory properties of curcumin. The present study focused on curcumin and its derivatives in the search for new iNOS inhibitors for the treatment of osteoarthritis. We conducted a molecular docking study on curcumin and its four derivatives; cyclocurcumin, tetrahydrocurcumin, demethoxycurcumin and curcumin monoglucoside with iNOS using CLC Drug discovery work bench 3.02. We selected two co-crystallized ligands for this study; tetrahydrobiopterin and N-omega-propyl-L-arginine present in complex with the enzyme iNOS. Results showed the best binding affinity of N-omega-propyl-L-arginine with cyclocurcumin and curcumin monoglucoside that exhibit binding energies of -65.2 kcal/mol and -68 kcal/mol respectively. Whereas with tetrahydrobiopterin, best binding scores of -64.7 kcal/mol and -62.2 kcal/mol were found with tetrahydrocurcumin and demethoxycurcumin respectively. This information could open doors of research for the designing of novel drugs using herbs such as curcumin for the treatment of inflammatory joint diseases.

Keywords: curcumin, iNOS, molecular docking, osteoarthritis

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1549 Identification and Evaluation of Environmental Concepts in Paulo Coelho's "The Alchemist"

Authors: Tooba Sabir, Asima Jaffar, Namra Sabir, Mohammad Amjad Sabir

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Ecocriticism is the study of relationship between human and environment which has been represented in literature since the very beginning in pastoral tradition. However, the analysis of such representation is new as compared to the other critical evaluations like Psychoanalysis, Marxism, Post-colonialism, Modernism and many others. Ecocritics seek to find information like anthropocentrism, ecocentrism, ecofeminism, eco-Marxism, representation of environment and environmental concept and several other topics. In the current study the representation of environmental concepts, were ecocritically analyzed in Paulo Coelho’s The Alchemist, one of the most read novels throughout the world, having been translated into many languages. Analysis of the text revealed, the representations of environmental ideas like landscapes and tourism, biodiversity, land-sea displacement, environmental disasters and warfare, desert winds and sand dunes. 'This desert was once a sea' throws light on different theories of land-sea displacement, one being the plate-tectonic theory which proposes Earth’s lithosphere to be divided into different large and small plates, continuously moving toward, away from or parallel to each other, resulting in land-sea displacement. Another theory is the continental drift theory which holds onto the belief that one large landmass—Pangea, broke down into smaller pieces of land that moved relative to each other and formed continents of the present time. The cause of desertification may, however, be natural i.e. climate change or artificial i.e. by human activities. Imagery of the environmental concepts, at some instances in the novel, is detailed and at other instances, is not as striking, but still is capable of arousing readers’ imagination. The study suggests that ecocritical justifications of environmental concepts in the text will increase the interactions between literature and environment which should be encouraged in order to induce environmental awareness among the readers.

Keywords: biodiversity, ecocritical analysis, ecocriticism, environmental disasters, landscapes

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1548 Phosphate Regulation of Arbuscular Mycorrhiza Symbiosis in Rice

Authors: Debatosh Das, Moxian Chen, Jianhua Zhang, Caroline Gutjahr

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Arbuscular mycorrhiza (AM) is a mutualistic symbiosis between plant roots and Glomeromycotina fungi, which is activated under low but inhibited by high phosphate. The effect of phosphate on AM development has been observed for many years, but mechanisms regulating it under contrasting phosphate levels remain unknown. Based on previous observations that promoters of several AM functional genes contain PHR binding motifs, we hypothesized that PHR2, a master regulator of phosphate starvation response in rice, was recruited to regulate AM symbiosis development. We observed a drastic reduction in root colonization and significant AM transcriptome modulation in phr2. PHR2 targets genes required for root colonization and AM signaling. The role of PHR2 in improving root colonization, mycorrhizal phosphate uptake, and growth response was confirmed in field soil. In conclusion, rice PHR2, which is considered a master regulator of phosphate starvation responses, acts as a positive regulator of AM symbiosis between Glomeromycotina fungi and rice roots. PHR2 directly targets the transcription of plant strigolactone and AM genes involved in the establishment of this symbiosis. Our work facilitates an understanding of ways to enhance AMF propagule populations introduced in field soils (as a biofertilizer) in order to restore the natural plant-AMF networks disrupted by modern agricultural practices. We show that PHR2 is required for AM-mediated improvement of rice yield in low phosphate paddy field soil. Thus, our work contributes knowledge for rational application of AM in sustainable agriculture. Our data provide important insights into the regulation of AM by the plant phosphate status, which has a broad significance in agriculture and terrestrial ecosystems.

Keywords: biofertilizer, phosphate, mycorrhiza, rice, sustainable, symbiosis

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1547 Arothron Stellatus Fish Skin Collagen Based Composite Biosheet Incorporated with Mupirocin as a Potential Dermal Substitute for Skin Tissue Regeneration

Authors: Giriprasath Ramanathan, Sivakumar Singaravelu, M. D. Raja, Uma Tirichurapalli Sivagnanam

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Collagen is the abundant protein found in the skin of the animal body that has been designed to provide adequate structural support for the adhesion of cells. The dressing material widely used for tissue engineering and biomedical application has to posses good swelling and biological property for the absorption of exudates and cell proliferation. Acid solubilised collagen from the fish skin of the Arothron stellatus was extracted. The collagen with hydroxypropyl and carboxy methyl cellulose has the better biological property to enhance the healing efficiency. The inter property of collagen with interesting perspectives in the tissue engineering process leads to the development of biomaterial with natural polymer with biologically derived collagen. Keeping this as an objective, the composite biomaterial was fabricated to improve the wound healing and biological properties. In this study the collagen from Arothron stellatus fish skin (ACO) was uniformly blended separately with hydroxypropyl methyl cellulose (HPMC) and carboxyl methyl cellulose (CMC) as biosheets. The casted biosheets were impregnated with mupirocin to get rid of infection from the microbes. Further, the results obtained from differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), tensile studies and biocompatibility of the biosheets were assessed. The swelling, porosity and degradation of the casted biosheets were studied to make the biosheets as a suitable wound dressing material. ACO-HPMC and ACO-CMC biosheets both showed good results, but ACO-HPMC biosheet showed better results than ACO-CMC and hence it can be used as a potential dermal substitute in skin tissue engineering.

Keywords: arothron stellatus, biocompatibility, collagen, tensile strenght

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1546 Investigation of the Jupiter’s Galilean Moons

Authors: Revaz Chigladze

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The purpose of the research is to investigate the surfaces of Jupiter's Galilean moons, namely which moon has the most uniform surface among them, what is the difference between the front (in the direction of motion) and the back sides of each moon's surface, as well as the temporal variations of the moons. Since 1981, the E. Kharadze National Astrophysical Observatory of Georgia has been conducting polarimetric (P) and photometric (M) observations of Jupiter's Galilean moons with telescopes of different diameters (40 cm and 125 cm) and the polarimeter ASEP-78 in combination with them and the latest generation photometer with a polarimeter and modern light receiver SBIG. As it turns out from the analysis of the observed material, the parameters P and M depend on α-the phase angle of the moon (satellite), L- the orbital latitude of the moon (satellite), λ- the wavelength, and t - the period of observation, i.e., P = P (α, L, λ , t), and similarly M = M (α, L, λ. , t). Based on the analysis of the observed material, the following was studied: Jupiter's Galilean moons: dependence of the magnitude and phase angle of the degree of linear polarization for different wavelengths; Dependence of the degree of polarization and the orbital longitude; dependence between the magnitude of the degree of polarization and the wavelength; time dependence of the degree of polarization and the dependence between photometric and polarimetric characteristics (including establishing correlation). From the analysis of the obtained results, we get: The magnitude of the degree of polarization of Jupiter's Galilean moons near the opposition significantly differs from zero. Europa appears to have the most uniform surface, and Callisto the least uniform. Time variations are most characteristic of Io, which confirms the presence of volcanic activity on its surface. Based on the observed material, it can be seen that the intensity of light reflected from the front hemisphere of the first three moons: Io, Europa, and Ganymede, is less than the intensity of light reflected from the rear hemisphere, and in the case of the Callisto it is the opposite. The paper provides a convincing (natural, real) explanation of this fact.

Keywords: Galilean moons, polarization, degree of polarization, photometry, front and rear hemispheres

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1545 In vitro Assessment of Bioactive Properties and Dose-Dependent Antioxidant Activities of Commercial Grape Cultivars in Taiwan

Authors: Kandi Sridhar, Charles Albert Linton

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Grapes are excellent sources of bioactive compounds, which have been suggested to be responsible for lowering the risk of chronic diseases. Fresh and freeze-dried extracts of Kyoho and Jubilee, commercial grape varieties available in Taiwan and attractive for their quality berries, were investigated for their total phenolics and total flavonoids contents and related dose-dependent antioxidants properties using various in vitro assays. The efficiency of the extraction yield ranged from 7.10 % to 25.53 % (w/w), depending on solvent used. Fresh samples of Kyoho and Jubilee exhibited total polyphenolic contents (351.56 ± 23.08 and 328.67 ± 16.54 µg GAE/mL, respectively), whereas Kyoho freeze-dried methanol: water extracts contains the good levels of total flavonoids (4767.82 ± 22.20 µg QE/mL). Kyoho and Jubilee freeze-dried extracts exhibited the highest total flavonoid contents. There was a weak correlation between total phenolic and flavonoid assays (r= -0.05, R2 = 0.02, p > 0.05). Kyoho fresh and freeze-dried samples showed the DPPH (11.51 – 77.82 %), superoxide scavenging activity (33.61 – 81.95 %), and total antioxidant inhibition (92.01 – 99.28 %), respectively. Total flavonoids were statistically correlated with EC50 DPPH scavenging radicals (r =0.91, p < 0.01), EC50 nitric oxide (r = 0.25, p > 0.05), and EC50 lipid peroxidation radicals (r = 0.38, p > 0.05). These results suggested that the two commercial grape cultivars in Taiwan could be used as a good source of natural antioxidants. Thus, consumption of grapes as a source antioxidant might lower the risk of chronic diseases. Moreover, future studies will investigate and develop phenolic acid profile for the cultivars in Taiwan.

Keywords: antioxidants, EC50 radical scavenging activity, grape cultivars, total phenolics

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1544 Ultra-High Voltage Energization of Electrostatic Precipitators for Coal Fired Boilers

Authors: Mads Kirk Larsen

Abstract:

Strict air pollution control is today high on the agenda world-wide. By reducing the particular emission, not only the mg/Nm3 will be reduced – also parts of mercury and other hazardous matters attached to the particles will be reduced. Furthermore, it is possible to catch the fine particles (PM2.5). For particulate control, the precipitators are still the preferred choice and much efforts have been done to improve the efficiencies. Many ESP’s have seen electrical upgrading by changing the traditional 1 phase power system into either 3 phase or SMPS (High Frequency) units. However, there exist a 4th type of power supply – the pulse type. This is unfortunately widely unknown, but may be of great benefit to power plants. The FLSmidth type is called COROMAX® and it is a high voltage pulse generator for precipitators using a semiconductor switch operating at medium potential. The generated high voltage pulses have rated amplitude of 80 kV and duration of 75 μs and are superimposed on a variable base voltage of 60 kV rated voltage. Hereby, achieving a peak voltage of 140 kV. COROMAX® has the ability to increase the voltage beyond the natural spark limit inside the precipitator. Voltage levels may often be twice as high after installation of COROMAX®. Hereby also the migration velocity increases and thereby the efficiency. As the collection efficiency is proportional to the voltage peak and mean values, this also increases the collection efficiency of the fine particles where test has shown 80% removal of particles less than 0.07 micron. Another great advantage is the indifference to back-corona. Simultaneously with emission reduction, the power consumption will also be reduced. Another great advantage of the COROMAX® system is that the emission can be improved without the need to change the internal parts or enlarge the ESP. Recently, more than 150 units have been installed in China, where emissions have been reduced to ultra-low levels.

Keywords: eleectrostatic precipitator, high resistivity dust, micropulse energization, particulate removal

Procedia PDF Downloads 282
1543 Comparative Correlation Investigation of Polynuclear Aromatic Hydrocarbons (PAHs) in Soils of Different Land Uses: Sources Evaluation Perspective

Authors: O. Onoriode Emoyan, E. Eyitemi Akporhonor, Charles Otobrise

Abstract:

Polycyclic Aromatic Hydrocarbons (PAHs) are formed mainly as a result of incomplete combustion of organic materials during industrial, domestic activities or natural occurrence. Their toxicity and contamination of terrestrial and aquatic ecosystem have been established. Though with limited validity index, previous research has focused on PAHs isomer pair ratios of variable physicochemical properties in source identification. The objective of this investigation was to determine the empirical validity of Pearson correlation coefficient (PCC) and cluster analysis (CA) in PAHs source identification along soil samples of different land uses. Therefore, 16 PAHs grouped as endocrine disruption substances (EDSs) were determined in 10 sample stations in top and sub soils seasonally. PAHs was determined the use of Varian 300 gas chromatograph interfaced with flame ionization detector. Instruments and reagents used are of standard and chromatographic grades respectively. PCC and CA results showed that the classification of PAHs along kinetically and thermodyanamically-favoured and those derived directly from plants product through biologically mediated processes used in source signature is about the predominance PAHs are likely to be. Therefore the observed PAHs in the studied stations have trace quantities of the vast majority of the sixteen un-substituted PAHs which may ultimately inhabit the actual source signature authentication. Type and extent of bacterial metabolism, transformation products/substrates, and environmental factors such as: salinity, pH, oxygen concentration, nutrients, light intensity, temperature, co-substrates and environmental medium are hereby recommended as factors to be considered when evaluating possible sources of PAHs.

Keywords: comparative correlation, kinetically and thermodynamically-favored PAHs, pearson correlation coefficient, cluster analysis, sources evaluation

Procedia PDF Downloads 401
1542 Cascaded Transcritical/Supercritical CO2 Cycles and Organic Rankine Cycles to Recover Low-Temperature Waste Heat and LNG Cold Energy Simultaneously

Authors: Haoshui Yu, Donghoi Kim, Truls Gundersen

Abstract:

Low-temperature waste heat is abundant in the process industries, and large amounts of Liquefied Natural Gas (LNG) cold energy are discarded without being recovered properly in LNG terminals. Power generation is an effective way to utilize low-temperature waste heat and LNG cold energy simultaneously. Organic Rankine Cycles (ORCs) and CO2 power cycles are promising technologies to convert low-temperature waste heat and LNG cold energy into electricity. If waste heat and LNG cold energy are utilized simultaneously in one system, the performance may outperform separate systems utilizing low-temperature waste heat and LNG cold energy, respectively. Low-temperature waste heat acts as the heat source and LNG regasification acts as the heat sink in the combined system. Due to the large temperature difference between the heat source and the heat sink, cascaded power cycle configurations are proposed in this paper. Cascaded power cycles can improve the energy efficiency of the system considerably. The cycle operating at a higher temperature to recover waste heat is called top cycle and the cycle operating at a lower temperature to utilize LNG cold energy is called bottom cycle in this study. The top cycle condensation heat is used as the heat source in the bottom cycle. The top cycle can be an ORC, transcritical CO2 (tCO2) cycle or supercritical CO2 (sCO2) cycle, while the bottom cycle only can be an ORC due to the low-temperature range of the bottom cycle. However, the thermodynamic path of the tCO2 cycle and sCO2 cycle are different from that of an ORC. The tCO2 cycle and the sCO2 cycle perform better than an ORC for sensible waste heat recovery due to a better temperature match with the waste heat source. Different combinations of the tCO2 cycle, sCO2 cycle and ORC are compared to screen the best configurations of the cascaded power cycles. The influence of the working fluid and the operating conditions are also investigated in this study. Each configuration is modeled and optimized in Aspen HYSYS. The results show that cascaded tCO2/ORC performs better compared with cascaded ORC/ORC and cascaded sCO2/ORC for the case study.

Keywords: LNG cold energy, low-temperature waste heat, organic Rankine cycle, supercritical CO₂ cycle, transcritical CO₂ cycle

Procedia PDF Downloads 225
1541 Dairy Wastewater Treatment by Electrochemical and Catalytic Method

Authors: Basanti Ekka, Talis Juhna

Abstract:

Dairy industrial effluents originated by the typical processing activities are composed of various organic and inorganic constituents, and these include proteins, fats, inorganic salts, antibiotics, detergents, sanitizers, pathogenic viruses, bacteria, etc. These contaminants are harmful to not only human beings but also aquatic flora and fauna. Because consisting of large classes of contaminants, the specific targeted removal methods available in the literature are not viable solutions on the industrial scale. Therefore, in this on-going research, a series of coagulation, electrochemical, and catalytic methods will be employed. The bulk coagulation and electrochemical methods can wash off most of the contaminants, but some of the harmful chemicals may slip in; therefore, specific catalysts designed and synthesized will be employed for the removal of targeted chemicals. In the context of Latvian dairy industries, presently, work is under progress on the characterization of dairy effluents by total organic carbon (TOC), Inductively Coupled Plasma Mass Spectrometry (ICP-MS)/ Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), High-Performance Liquid Chromatography (HPLC), Gas Chromatography-Mass Spectrometry (GC-MS), and Mass Spectrometry. After careful evaluation of the dairy effluents, a cost-effective natural coagulant will be employed prior to advanced electrochemical technology such as electrocoagulation and electro-oxidation as a secondary treatment process. Finally, graphene oxide (GO) based hybrid materials will be used for post-treatment of dairy wastewater as graphene oxide has been widely applied in various fields such as environmental remediation and energy production due to the presence of various oxygen-containing groups. Modified GO will be used as a catalyst for the removal of remaining contaminants after the electrochemical process.

Keywords: catalysis, dairy wastewater, electrochemical method, graphene oxide

Procedia PDF Downloads 119
1540 IOT Based Automated Production and Control System for Clean Water Filtration Through Solar Energy Operated by Submersible Water Pump

Authors: Musse Mohamud Ahmed, Tina Linda Achilles, Mohammad Kamrul Hasan

Abstract:

Deterioration of the mother nature is evident these day with clear danger of human catastrophe emanating from greenhouses (GHG) with increasing CO2 emissions to the environment. PV technology can help to reduce the dependency on fossil fuel, decreasing air pollution and slowing down the rate of global warming. The objective of this paper is to propose, develop and design the production of clean water supply to rural communities using an appropriate technology such as Internet of Things (IOT) that does not create any CO2 emissions. Additionally, maximization of solar energy power output and reciprocally minimizing the natural characteristics of solar sources intermittences during less presence of the sun itself is another goal to achieve in this work. The paper presents the development of critical automated control system for solar energy power output optimization using several new techniques. water pumping system is developed to supply clean water with the application of IOT-renewable energy. This system is effective to provide clean water supply to remote and off-grid areas using Photovoltaics (PV) technology that collects energy generated from the sunlight. The focus of this work is to design and develop a submersible solar water pumping system that applies an IOT implementation. Thus, this system has been executed and programmed using Arduino Software (IDE), proteus, Maltab and C++ programming language. The mechanism of this system is that it pumps water from water reservoir that is powered up by solar energy and clean water production was also incorporated using filtration system through the submersible solar water pumping system. The filtering system is an additional application platform which is intended to provide a clean water supply to any households in Sarawak State, Malaysia.

Keywords: IOT, automated production and control system, water filtration, automated submersible water pump, solar energy

Procedia PDF Downloads 68
1539 Deterministic and Stochastic Modeling of a Micro-Grid Management for Optimal Power Self-Consumption

Authors: D. Calogine, O. Chau, S. Dotti, O. Ramiarinjanahary, P. Rasoavonjy, F. Tovondahiniriko

Abstract:

Mafate is a natural circus in the north-western part of Reunion Island, without an electrical grid and road network. A micro-grid concept is being experimented in this area, composed of a photovoltaic production combined with electrochemical batteries, in order to meet the local population for self-consumption of electricity demands. This work develops a discrete model as well as a stochastic model in order to reach an optimal equilibrium between production and consumptions for a cluster of houses. The management of the energy power leads to a large linearized programming system, where the time interval of interest is 24 hours The experimental data are solar production, storage energy, and the parameters of the different electrical devices and batteries. The unknown variables to evaluate are the consumptions of the various electrical services, the energy drawn from and stored in the batteries, and the inhabitants’ planning wishes. The objective is to fit the solar production to the electrical consumption of the inhabitants, with an optimal use of the energies in the batteries by satisfying as widely as possible the users' planning requirements. In the discrete model, the different parameters and solutions of the linear programming system are deterministic scalars. Whereas in the stochastic approach, the data parameters and the linear programming solutions become random variables, then the distributions of which could be imposed or established by estimation from samples of real observations or from samples of optimal discrete equilibrium solutions.

Keywords: photovoltaic production, power consumption, battery storage resources, random variables, stochastic modeling, estimations of probability distributions, mixed integer linear programming, smart micro-grid, self-consumption of electricity.

Procedia PDF Downloads 94
1538 Seismicity and Ground Response Analysis for MP Tourism Office in Indore, India

Authors: Deepshikha Shukla, C. H. Solanki, Mayank Desai

Abstract:

In the last few years, it has been observed that earthquake is proving a threat to the scientist across the world. With a large number of earthquakes occurring in day to day life, the threat to life and property has increased manifolds which call for an urgent attention of all the researchers globally to carry out the research in the field of Earthquake Engineering. Any hazard related to the earthquake and seismicity is considered to be seismic hazards. The common forms of seismic hazards are Ground Shaking, Structure Damage, Structural Hazards, Liquefaction, Landslides, Tsunami to name a few. Among all the natural hazards, the most devastating and damaging is the earthquake as all other hazards are triggered only after the occurrence of an earthquake. In order to quantify and estimate the seismicity and seismic hazards, many methods and approaches have been proposed in the past few years. Such approaches are Mathematical, Conventional and Computational. Convex Set Theory, Empirical Green’s Function are some of the Mathematical Approaches whereas the Deterministic and Probabilistic Approaches are the Conventional Approach for the estimation of the seismic Hazards. Ground response and Ground Shaking of a particular area or region plays an important role in the damage caused due to the earthquake. In this paper, seismic study using Deterministic Approach and 1 D Ground Response Analysis has been carried out for Madhya Pradesh Tourism Office in Indore Region in Madhya Pradesh in Central India. Indore lies in the seismic zone III (IS: 1893, 2002) in the Seismic Zoning map of India. There are various faults and lineament in this area and Narmada Some Fault and Gavilgadh fault are the active sources of earthquake in the study area. Deepsoil v6.1.7 has been used to perform the 1 D Linear Ground Response Analysis for the study area. The Peak Ground Acceleration (PGA) of the city ranges from 0.1g to 0.56g.

Keywords: seismicity, seismic hazards, deterministic, probabilistic methods, ground response analysis

Procedia PDF Downloads 146
1537 Childhood Warscape, Experiences from Children of War Offer Key Design Decisions for Safer Built Environments

Authors: Soleen Karim, Meira Yasin, Rezhin Qader

Abstract:

Children’s books present a colorful life for kids around the world, their current environment or what they could potentially have- a home, two loving parents, a playground, and a safe school within a short walk or bus ride. These images are only pages in a donated book for children displaced by war. The environment they live in is significantly different. Displaced children are faced with a temporary life style filled with fear and uncertainty. Children of war associate various structural institutions with a trauma and cannot enter the space, even if it is for their own future development, such as a school. This paper is a collaborative effort with students of the Kennesaw State University architecture department, architectural designers and a mental health professional to address and link the design challenges and the psychological trauma for children of war. The research process consists of a) interviews with former refugees, b) interviews with current refugee children, c) personal understanding of space through one’s own childhood, d) literature review of tested design methods to address various traumas. Conclusion: In addressing the built environment for children of war, it is necessary to address mental health and well being through the creation of space that is sensitive to the needs of children. This is achieved by understanding critical design cues to evoke normalcy and safe space through program organization, color, and symbiosis of synthetic and natural environments. By involving the children suffering from trauma in the design process, aspects of the design are directly enhanced to serve the occupant. Neglecting to involve the participants creates a nonlinear design outcome and does not serve the needs of the occupant to afford them equal opportunity learning and growth experience as other children around the world.

Keywords: activist architecture, childhood education, childhood psychology, adverse childhood experiences

Procedia PDF Downloads 122
1536 Analysis of Aerodynamic Forces Acting on a Train Passing Through a Tornado

Authors: Masahiro Suzuki, Nobuyuki Okura

Abstract:

The crosswind effect on ground transportations has been extensively investigated for decades. The effect of tornado, however, has been hardly studied in spite of the fact that even heavy ground vehicles, namely, trains were overturned by tornadoes with casualties in the past. Therefore, aerodynamic effects of the tornado on the train were studied by several approaches in this study. First, an experimental facility was developed to clarify aerodynamic forces acting on a vehicle running through a tornado. Our experimental set-up consists of two apparatus. One is a tornado simulator, and the other is a moving model rig. PIV measurements showed that the tornado simulator can generate a swirling-flow field similar to those of the natural tornadoes. The flow field has the maximum tangential velocity of 7.4 m/s and the vortex core radius of 96 mm. The moving model rig makes a 1/40 scale model train of single-car/three-car unit run thorough the swirling flow with the maximum speed of 4.3 m/s. The model car has 72 pressure ports on its surface to estimate the aerodynamic forces. The experimental results show that the aerodynamic forces vary its magnitude and direction depends on the location of the vehicle in the flow field. Second, the aerodynamic forces on the train were estimated by using Rankin vortex model. The Rankin vortex model is a simple tornado model which widely used in the field of civil engineering. The estimated aerodynamic forces on the middle car were fairly good agreement with the experimental results. Effects of the vortex core radius and the path of the train on the aerodynamic forces were investigated using the Rankin vortex model. The results shows that the side and lift forces increases as the vortex core radius increases, while the yawing moment is maximum when the core radius is 0.3875 times of the car length. Third, a computational simulation was conducted to clarify the flow field around the train. The simulated results qualitatively agreed with the experimental ones.

Keywords: aerodynamic force, experimental method, tornado, train

Procedia PDF Downloads 218
1535 Biogas from Cover Crops and Field Residues: Effects on Soil, Water, Climate and Ecological Footprint

Authors: Manfred Szerencsits, Christine Weinberger, Maximilian Kuderna, Franz Feichtinger, Eva Erhart, Stephan Maier

Abstract:

Cover or catch crops have beneficial effects for soil, water, erosion, etc. If harvested, they also provide feedstock for biogas without competition for arable land in regions, where only one main crop can be produced per year. On average gross energy yields of approx. 1300 m³ methane (CH4) ha-1 can be expected from 4.5 tonnes (t) of cover crop dry matter (DM) in Austria. Considering the total energy invested from cultivation to compression for biofuel use a net energy yield of about 1000 m³ CH4 ha-1 is remaining. With the straw of grain maize or Corn Cob Mix (CCM) similar energy yields can be achieved. In comparison to catch crops remaining on the field as green manure or to complete fallow between main crops the effects on soil, water and climate can be improved if cover crops are harvested without soil compaction and digestate is returned to the field in an amount equivalent to cover crop removal. In this way, the risk of nitrate leaching can be reduced approx. by 25% in comparison to full fallow. The risk of nitrous oxide emissions may be reduced up to 50% by contrast with cover crops serving as green manure. The effects on humus content and erosion are similar or better than those of cover crops used as green manure when the same amount of biomass was produced. With higher biomass production the positive effects increase even if cover crops are harvested and the only digestate is brought back to the fields. The ecological footprint of arable farming can be reduced by approx. 50% considering the substitution of natural gas with CH4 produced from cover crops.

Keywords: biogas, cover crops, catch crops, land use competition, sustainable agriculture

Procedia PDF Downloads 528
1534 Spatial Interactions Between Earthworm Abundance and Tree Growth Characteristics in Western Niger Delta

Authors: Olatunde Sunday Eludoyin, Charles Obiechina Olisa

Abstract:

The study examined the spatial interactions between earthworm abundance (EA) and tree growth characteristics in ecological belts of Western Niger Delta, Nigeria. Eight 20m x 20m quadrat were delimited in the natural vegetation in each of the rainforest (RF), mangrove (M), fresh water swamp (FWS), and guinea savanna (GS) ecological belts to gather data about the tree species (TS) characteristics which included individual number of tree species (IN), diversity (Di), density (De) and richness (Ri). Three quadrats of 1m x 1m were delineated in each of the 20m x 20m quadrats to collect earthworm species the topsoil (0-15cm), and subsoil (15-30cm) and were taken to laboratory for further analysis. Descriptive statistics and inferential statistics were used for data analysis. Findings showed that a total of 19 earthworm species was found, with 58.5% individual species recorded in the topsoil and 41.5% recorded in the subsoil. The total population ofEudriliuseugeniae was predominantly highest in both topsoil (38.4%) and subsoil (27.1%). The total population of individual species of earthworm was least in GS in the topsoil (11.9%) and subsoil (8.4%). A total of 40 different species of TS was recorded, of which 55.5% were recorded in FWS, while RF was significantly highest in the species diversity(0.5971). Regression analysis revealed that Ri, IN, DBH, Di, and De of trees explained 65.9% of the variability of EA in the topsoil, while 46.9 % of the variability of earthworm abundance was explained by the floristic parameters in the subsoil.Similarly, correlation statistics revealed that in the topsoil, EA is positively and significantly correlated with Ri (r=0.35; p<0.05), IN (r=0.523; p<0.05) and De (r=0.469; p<0.05) while DBH was negatively and significantly correlated with earthworm abundance (r=-0.437; p<0.05). In the subsoil, only Ri and DBH correlated significantly with EA. The study concluded that EA in the study locations was highly influenced by tree growth species especially Ri, IN, DBH, Di, and De. The study recommended that the TSabundance should be improved in the study locations to ensure the survival of earthworms for ecosystem functions.

Keywords: interactions, earthworm abundance, tree growth, ecological zones, western niger delta

Procedia PDF Downloads 79
1533 Study on the Mechanism of CO₂-Viscoelastic Fluid Synergistic Oil Displacement in Tight Sandstone Reservoirs

Authors: Long Long Chen, Xinwei Liao, Shanfa Tang, Shaojing Jiang, Ruijia Tang, Rui Wang, Shu Yun Feng, Si Yao Wang

Abstract:

Tight oil reservoirs have poor physical properties, insufficient formation energy, and low natural productivity; it is necessary to effectively improve their crude oil recovery. CO₂ flooding is an important technical means to enhance oil recovery and achieve effective CO₂ storage in tight oil reservoirs, but its heterogeneity is strong, which makes CO₂ flooding prone to gas channeling and poor recovery. Aiming at the problem of gas injection channeling, combined with the excellent performance of low interfacial tension viscoelastic fluid (GOBTK), the research on CO₂-low interfacial tension viscoelastic fluid synergistic oil displacement in tight reservoirs was carried out, and the synergy of CO₂ and low interfacial tension viscoelastic fluid was discussed. Oil displacement mechanism. Experiments show that GOBTK has good injectability in tight oil reservoirs (Kg=0.141~0.793mD); CO₂-0.4% GOBTK synergistic flooding can improve the recovery factor of low permeability layers (31.41%) under heterogeneous (gradient difference of 10) conditions the) effect is better than that of CO₂ flooding (0.56%) and 0.4% GOBT-water flooding (20.99%); CO₂-GOBT synergistic oil displacement mechanism includes: 1) The formation of CO₂ foam increases the flow resistance of viscoelastic fluid, forcing the displacement fluid to flow 2) GOBTK can emulsify and disperse residual oil into small oil droplets, and smoothly pass through narrow pores to produce; 3) CO₂ dissolved in GOBTK synergistically enhances the water wettability of the core, and the use of viscosity Elastomeric fluid injection and stripping of residual oil; 4) CO₂-GOBTK synergy superimposes multiple mechanisms, effectively improving the swept volume and oil washing efficiency of the injected fluid to the reservoir.

Keywords: tight oil reservoir, CO₂ flooding, low interfacial tension viscoelastic fluid flooding, synergistic oil displacement, EOR mechanism

Procedia PDF Downloads 158