Search results for: organic pollutant degradation

Authors: Ankit Patil, Tushar D. Deshpande, Yogesh M. Nimdeo

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Pickering emulsions (PE) were developed in response to increased demand for organic, eco-friendly, and biocompatible products. These emulsions are usually stabilized by solid particles. In this research, we created chitosan-based sunflower oil-in-water (O/W) PE without the need for a surfactant. In our work, we employed chitosan, a biopolymer derived from chitin, as a stabilizer. This decision was influenced by chitosan's biocompatibility and biodegradability, as well as its anti-inflammatory and antibacterial capabilities. It also has other functional properties, such as antioxidant activity, a probiotic delivery mechanism, and the ability to encapsulate bioactive compounds. The purpose of this study was to govern key parameters that can be changed to obtain stable PE, such as the concentration of chitosan (0.3-0.5 wt.%), the concentration of oil (0.8-1 vol%), the pH of the emulsion (3-7) manipulated by the addition of 1M HCl/ 4M NaOH, and the amount of electrolyte (NaCl-0-300mM) added to increase or decrease ionic strength. A careful combination of these properties resulted in the production of the most stable and optimal PE. Particle size study found that emulsions with pH 6, 0.4% chitosan, and 300 mM salts were exceptionally stable, with droplet size 886 nm, PI of 0.1702, and zeta potential of 32.753.83 mV. It is fair to infer that when ionic strength rises, particle size, zeta potential, and PI value decrease. A lower PI value suggests that emulsion nanoparticles are more homogeneous. The addition of sodium chloride increases the ionic strength of the emulsion, facilitating the formation of more compact and ordered particle layers. These findings provide light on the creation of stimulus-responsive chitosan-based PE capable of encapsulating bioactive materials, functioning as antioxidants, and serving as food-grade emulsifiers.

Keywords: pickering emulsion, biocompatibility, eco-friendly, chitosan

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Authors: Aleksandra BužArovska, Gordana Bogoeva Gaceva

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Biodegradable polymers have received significant scientific attention in tissue engineering (TE) application, in particular their composites consisting of inorganic nanoparticles. In the last 15 years, they are subject of intensive research by many groups, aiming to develop polymer scaffolds with defined biodegradability, porosity and adequate mechanical stability. The most important characteristic making these materials attractive for TE is their biodegradability, a process that could be time controlled and long enough to enable generation of a new tissue as a replacement for the degraded polymer scaffold. In this work poly(L-lactic acid) scaffolds, filled with TiO2 nanoparticles functionalized with oleic acid, have been prepared by thermally induced phase separation method (TIPS). The functionalization of TiO2 nanoparticles with oleic acid was performed in order to improve the nanoparticles dispersibility within the polymer matrix and at the same time to inhibit the cytotoxicity of the nanofiller. The oleic acid was chosen as amphiphilic molecule belonging to the fatty acid family because of its non-toxicity and possibility for mediation between the hydrophilic TiO2 nanoparticles and hydrophobic PLA matrix. The produced scaffolds were characterized with thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and mechanical compression measurements. The bioactivity for bone tissue engineering application was tested in supersaturated simulated body fluid. The degradation process was followed by Fourier transform infrared spectroscopy (FTIR). The results showed anisotropic morphology with elongated open pores (100 µm), high porosity (around 92%) and perfectly dispersed nanofiller. The compression moduli up to 10 MPa were identified independent on the nanofiller content. Functionalized TiO2 nanoparticles induced formation of hydroxyapatite clusters as much as unfunctionalized TiO2. The prepared scaffolds showed properties ideal for scaffold vascularization, cell attachment, growth and proliferation.

Keywords: biodegradation, bone tissue engineering, mineralization, PLA scaffolds

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Authors: Mohit Wadhawan, Sushma Rathaur

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Lymphatic filariasis, also called elephantiasis is a tropical disease afflicting over 120 million people in 81 countries worldwide. Existing anti filarial drugs are effective against the larval stages of filarial parasites which call for an urgent need of drugs which are macrofilaricidal. Identification of molecular targets crucial for survival of filarial parasites is a prerequisite for drug designing. Prolyl oligopeptidase (POP) is one such crucial enzyme involved in the maturation and degradation of neuropeptides and peptide hormones. We have identified this peptidase in the bovine filarial parasite, Setaria cervi. Effect of inhibition of POP on the proteome profile of filarial parasite has been discussed in this study. Filarial parasites were exposed to Z-pro-prolinal (ZPP), a specific POP inhibitor for 8 h and the motility and viability of the parasites was observed. It significantly reduced the motility and viability of the parasites. To study the proteome profile, the cytosolic, endoplasmic reticulum (ER) and mitochondrial extracts of the adult female parasites were subjected to 2-dimensional electrophoresis. As analyzed by the PD-Quest software, the ZPP caused the alteration in the different subcellular proteins, and the significantly altered proteins were identified using MALDI-MS/MS spectrometry. The major proteins identified were found to play important role in diverse biological functions like signaling, redox regulation, energy metabolism, stress response, and cytoskeleton formation. Moreover, we found upregulation in the calcium binding proteins such as calreticulin, calponin, and calpain-6 suggesting that POP inhibition regulates calcium release. This relates to earlier reports that POP plays non-catalytic role in inositol 1,4,5-trisphosphate (IP3) signaling inducing release of calcium from ER. Taken together, the data demonstrated that inhibition of prolyl oligopeptidase alter the overall proteome signifying its role in survival of the filarial parasites. Thus this study provides a basis for the use of POP as a chemotherapeutic target for the treatment of lymphatic filariasis.

Keywords: lymphatic filariasis, setaria cervi, prolyl oligopeptidase, proteomics

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Authors: Ihab Al-Mokrani

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The Arabic heritage has two types of spoken rhetoric: the first type which al-Jaahiz calls “the rhetoric of the sign,” which means body language, and the rhetoric of silence which is of no less importance than the rhetoric of the sign, the speaker’s appearance and movements, etc. The second type is the spoken performance of utterances which bears written rhetoric arts like metaphor, simile, metonymy, etc. Rationale of the study: First: in spite of the factual existence of rhetorical phenomena in the Arabic heritage, there has been no contemporary study handling the spoken rhetoric in the Arabic heritage. Second: Arabic Civilization is originally a spoken one. Comparing the Arabic culture and civilization, from one side, to the Greek, roman or Pharaonic cultures and civilizations, from the other side, shows that the latter cultures and civilizations started and flourished written while the former started among illiterate people who had no interest in writing until recently. That sort of difference on the part of the Arabic culture and civilization created a rhetoric different from rhetoric in the other cultures and civilizations. Third: the spoken nature of the Arabic civilization influenced the Arabic rhetoric in the sense that specific rhetorical arts have been introduced matching that spoken nature. One of these arts is the art of concision which compensates for the absence of writing’s means of preserving the text. In addition, this interprets why many of the definitions of the Arabic rhetoric were defining rhetoric as the art of concision. Also, this interprets the fact that the literary genres known in the Arabic culture were limited by the available narrow space like poetry, anecdotes, and stories, while the literary genres in the Greek culture were of wide space as epics and drama. This is not of any contrast to the fact that some Arabic poetry would exceed 100 lines of poetry as Arabic poetry was based on the line organic unity, which means that every line could stand alone with a full meaning that is not dependent on the rest of the poem; and that last aspect has never happened in any culture other than the Arabic culture.

Keywords: Arabic rhetoric, spoken rhetoric, Arabic heritage, culture

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Authors: Vasileios A. Giouvanis, Christos D. Papanikolaou, Dimitrios S. Dimakas, Maria A. Sakellariou-Makrantonaki

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In countries with limited water resources, where the irrigation demands are higher than the 70% of the total water use, the demand for fresh water increases while the quality of this natural resource is downgraded. The aromatic and pharmaceutical plants hold a high position in the culture of the most civilizations through the centuries. The ‘Mountain Tea,’ species of the Greek flora, is part of a series of aromatic plants and herbs that are famous for their pharmaceutical properties as well as their byproducts and their essential oils. The aim of this research was to study the effects of full and deficit irrigation on the growing and productive characteristics of organically cultivated ‘Mountain Tea’ (Sideritis raeseri). The research took place at the University of Thessaly farm in Velestino, Magnesia - Central Greece, during the year 2017, which was the third growing season. The experiment consisted of three treatments in three replications. The experimental design was a fully randomized complete block. Surface drip irrigation was used to irrigate the experimental plots. In the first treatment, the 75% (deficit irrigation) of the daily water needs was applied. In the second treatment, the 100% (full irrigation) of the daily water needs was applied. The third treatment was not irrigated (rainfed). The crop water needs were calculated according to the daily measured evapotranspiration (ETc) using the Penman-Monteith method (FAO 56). The plants’ height, fresh and dry biomass production were measured. The results showed that only the irrigated ‘Mountain Tea’ can be cultivated at low altitude areas with satisfactory results. Moreover, there are no statistically significant differences (P < 0.05) at the growing and productive characteristics between full and deficit irrigation treatments, which proves that by deficit irrigation, an important amount of irrigation water can be saved.

Keywords: mountain tea, surface drip irrigation, deficit irrigation, water saving

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Authors: Nompumelelo P. Mathebula, Roger A. Sheldon, Daniel P. Pienaar, Moira L. Bode

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The preparation of enantiopure Morita-Baylis-Hillman (MBH) adducts remains a challenge in organic chemistry. MBH adducts are highly functionalised compounds which act as key intermediates in the preparation of compounds of medicinal importance. MBH adducts are prepared in racemic form by reacting various aldehydes and activated alkenes in the presence of DABCO. Enantiopure MBH adducts can be obtained by employing Enzymatic kinetic resolution (EKR). This technique has been successfully demonstrated in our group, amongst others, using lipases in either hydrolysis or transesterification reactions. As these methods only allow 50% of each enantiomer to be obtained, our interest grew in exploring other enzymatic methods for the synthesis of enantiopure MBH adducts where, theoretically, 100% of the desired enantiomer could be obtained.Dehydrogenase enzymes can be employed on prochiral substrates to obtain optically pure compounds by reducing carbon-carbon double bonds or carbonyl groups of ketones. Ketoreductases have been used historically to obtain enantiopure secondary alcohols on an industrial scale. Ketoreductases are NAD(P)H-dependent enzymes and thus require nicotinamide as a cofactor. This project focuses on employing ketoreductase enzymes to selectively reduce ketones derived from Morita-Baylis-Hillman (MBH) adducts in order to obtain these adducts in enantiopure form.Results obtained from this study will be reported. Good enantioselectivity was observed using a range of different ketoreductases, however, reactions were complicated by the formation of an unexpected by-product, which was characterised employing single crystal x-ray crystallography techniques. Methods to minimise by-product formation are currently being investigated.

Keywords: ketoreductase, morita-baylis-hillman, selective reduction, x-ray crystallography

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Authors: P. Selyshchev

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Construction materials for nuclear facilities are operated under extreme thermal and radiation conditions. First of all, they are nuclear fuel, fuel assemblies, and reactor vessel. It places high demands on the control of their state, stability of their state, and their operating conditions. An irradiated material is a typical example of an open non-equilibrium system with nonlinear feedbacks between its elements. Fluxes of energy, matter and entropy maintain states which are far away from thermal equilibrium. The links that arise under irradiation are inherently nonlinear. They form the mechanisms of feed-backs that can lead to instability. Due to this instability the temperature of the sample, heat transfer, and the defect density can exceed the steady-state value in several times. This can lead to change of typical operation and an accident. Therefore, it is necessary to take into account the thermal instability to avoid the emergency situation. The point is that non-thermal energy can be accumulated in materials because irradiation produces defects (first of all these are vacancies and interstitial atoms), which are metastable. The stored energy is about energy of defect formation. Thus, an annealing of the defects is accompanied by releasing of non-thermal stored energy into thermal one. Temperature of the material grows. Increase of temperature results in acceleration of defect annealing. Density of the defects drops and temperature grows more and more quickly. The positive feed-back is formed and self-reinforcing annealing of radiation defects develops. To describe these phenomena a theoretical approach to thermal instability is developed via formalism of complex systems. We consider system of nonlinear differential equations for different components of microstructure and temperature. The qualitative analysis of this non-linear dynamical system is carried out. Conditions for development of instability have been obtained. Points of bifurcation have been found. Convenient way to represent obtained results is a set of phase portraits. It has been shown that different regimes of material state under irradiation can develop. Thus degradation of irradiated material can be limited by means of choice appropriate kind of evolution of materials under irradiation.

Keywords: irradiation, material, non-equilibrium state, nonlinear feed-back, thermal instability

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Authors: Piacentini Diego, Della Rovere Federica, Fattorini Laura, Lanni Francesca, Cittadini Martina, Altamura Maria Maddalena, Falasca Giuseppina

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Plants have evolved sophisticated mechanisms to cope with environmental cues. Changes in intracellular content and distribution of phytohormones, such as the auxin indole-3-acetic acid (IAA), have been involved in morphogenic adaptation to environmental stresses. In addition to phytohormones, plants can rely on a plethora of small signal molecules able to promptly sense and transduce the stress signals, resulting in morpho/physiological responses thanks also to their capacity to modulate the levels/distribution/reception of most hormones. Among these signaling molecules, nitrogen monoxide (nitric oxide – NO) is a critical component in several plant acclimation strategies to both biotic and abiotic stresses. Depending on its levels, NO increases plant adaptation by enhancing the enzymatic or non-enzymatic antioxidant systems or by acting as a direct scavenger of reactive oxygen/nitrogen (ROS/RNS) species produced during the stress. In addition, exogenous applications of NO-specific donor compounds showed the involvement of the signal molecule in auxin metabolism, transport, and signaling, under both physiological and stress conditions. However, the complex mechanisms underlying NO action in interacting with phytohormones, such as auxins, during metal stress responses are still poorly understood and need to be better investigated. Emphasis must be placed on the response of the root system since it is the first plant organ system to be exposed to metal soil pollution. The monocot Oryza sativa L. (rice) has been chosen given its importance as a stable food for some 4 billion people worldwide. In addition, increasing evidence has shown that rice is often grown in contaminated paddy soils with high levels of heavy metal cadmium (Cd) and metalloid arsenic (As). The facility through which these metals are taken up by rice roots and transported to the aerial organs up to the edible caryopses makes rice one of the most relevant sources of these pollutants for humans. This study aimed to evaluate if NO has a mitigatory activity in the roots of rice seedlings against Cd or As toxicity and to understand if this activity requires interactions with auxin. Our results show that exogenous treatments with the NO-donor SNP alleviate the stress induced by Cd, but not by As, in in-vitro-grown rice seedlings through increased intracellular root NO levels. The damages induced by the pollutants include root growth inhibition, root histological alterations and ROS (H2O2, O2●ˉ), and RNS (ONOOˉ) production. Also, SNP treatments mitigate both the root increase in root IAA levels and the IAA alteration in distribution monitored by the OsDR5::GUS system due to the toxic metal exposure. Notably, the SNP-induced mitigation of the IAA homeostasis altered by the pollutants does not involve changes in the expression of OsYUCCA1 and ASA2 IAA-biosynthetic genes. Taken together, the results highlight a mitigating role of NO in the rice root system, which is pollutant-specific, and involves the interaction of the signal molecule with both IAA and brassinosteroids at different (i.e., transport, levels, distribution) and multiple levels (i.e., transcriptional/post-translational levels). The research is supported by Progetti Ateneo Sapienza University of Rome, grant number: RG120172B773D1FF

Keywords: arsenic, auxin, cadmium, nitric oxide, rice, root system

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Authors: Ariana Kilic, Serena Arapyan

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Water pollution is a serious concern in all seas around the world and one major cause of it is dye textile wastes mixing with seawater. This common incident alters aquatic life, putting organisms’ lives in danger and deteriorating the water's nature. There is a significant need for a natural approach to reduce the amount of dye textile waste in seawater and ensure marine organisms' safety. Consequently, using marine algae is a viable solution since it can eliminate the excess waste by absorbing the dye. Also, marine algae are non-vascular that absorb water and nutrients, meaning that having them as absorbers is a natural process and no inorganic matters will be added to the seawater that could result in further pollution. To test the efficiency of this approach, the optical absorbance of the seawater samples was measured before and after the addition of marine algae by utilizing colorimetry. A colorimeter is used to find the concentration of a chemical compound in a solution by measuring the absorbance of the compound at a specific wavelength. Samples of seawater that have equal amounts of water were used and textile dye was added as the constant variables. The initial and final absorbances, the dependent variable, of the water were measured before and after the addition of marine algae, the independent variable, and observed. The lower the absorbance showed us that there is lower dye concentration and therefore, the marine algae had done its job by using and absorbing the dye. The same experiment was repeated with same amount of water but with different concentrations of dye in order to determine the maximum concentration of dye the marine algae can completely absorb. The diminished concentration of dye demonstrated that pollution caused by factories’ dye wastes could be prevented with the natural method of marine algae. The involvement of marine algae is an optimal strategy for having an organic solution to absorbing the dye wastes in seas and obstructing water pollution.

Keywords: water pollution, dye textile waste, marine algae, absorbance, colorimetry

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Authors: Qin Xvelian

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organic renewal" based on the development of existing resources in high-density urban areas has become the mainstream of urban development in the new era. As an important stock resource of public space in high-density urban areas, promoting its value remodeling is an effective way to alleviate the shortage of public space resources. However, due to the lack of evaluation links in the process of underpass space renewal, a large number of underpass space resources have been left idle, facing the problems of low space conversion efficiency, lack of accuracy in development decision-making, and low adaptability of functional positioning to citizens' needs. Therefore, it is of great practical significance to construct the evaluation system of under-bridge space renewal potential and explore the renewal mode. In this paper, some of the under-bridge spaces in the main urban area of Chongqing are selected as the research object. Through the questionnaire interviews with the users of the built excellent space under the bridge, three types of six levels and twenty-two potential evaluation indexes of "objective demand factor, construction feasibility factor and construction suitability factor" are selected, including six levels of land resources, infrastructure, accessibility, safety, space quality and ecological environment. The analytical hierarchy process and expert scoring method are used to determine the index weight, construct the potential evaluation system of the space under the bridge in high-density urban areas of Chongqing, and explore the direction of renewal and utilization of its suitability. To provide feasible theoretical basis and scientific decision support for the use of under bridge space in the future.

Keywords: high density urban area, potential evaluation, space under bridge, updated using

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Authors: Gergely Horváth

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The study presents the complexity of food safety dividing it into two layers. Beyond the basic layer of requirements, there is a more demanding higher level linked with quality and purity aspects. It would be important to give special prominence to both layers, given that massive illnesses are caused by foods even though officially licensed. Then the study discusses an exciting safety challenge stemming from the risks of genetically modified organisms (GMOs). Furthermore, it features legal case examples that illustrate how certain liability questions are solved or not yet decided in connection with the production of genetically modified crops. In addition, a special kind of land grabbing, more precisely land grabbing from non-GMO farming systems can also be noticed as well as a new phenomenon eroding food sovereignty. Coexistence, the state where organic, conventional, and GM farming systems are standing alongside each other is an unsuitable experiment that cannot be successful, because of biophysical reasons (such as cross-pollination). Agricultural and environmental lawyers both try to find the optimal solution. Agri-environmental measures are introduced as a special subfield of law maintaining also food safety. The important steps of agri-environmental legislation are aiming at the protection of natural values, the environmental media and strengthening food safety as well, practically the quality of agricultural products intended for human consumption. The major findings of the study focus on searching for the appropriate approach capable of solving the security and safety problems of food production. The most interesting concepts of the Hungarian national and EU food law legislation are analyzed in more detail with descriptive, analytic and comparative methods.

Keywords: food law, food safety, food security, GMO, Genetically Modified Organisms, agri-environmental measures

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Authors: Armando A. Rodríguez, Emilio Salceda, Anoland Garateix, André J. Zaharenko, Steve Peigneur, Omar López, Tirso Pons, Michael Richardson, Maylín Díaz, Yasnay Hernández, Ludger Ständker, Jan Tytgat, Enrique Soto

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Acid-sensing ion channels are cation (Na+) channels activated by a pH drop. These proteins belong to the ENaC/degenerin superfamily of sodium channels. ASICs are involved in sensory perception, synaptic plasticity, learning, memory formation, cell migration and proliferation, nociception, and neurodegenerative disorders, among other processes; therefore those molecules that specifically target these channels are of growing pharmacological and biomedical interest. Sea anemones produce a large variety of ion channels peptide toxins; however, those acting on ligand-gated ion channels, such as Glu-gated, Ach-gated ion channels, and acid-sensing ion channels (ASICs), remain barely explored. The peptide PhcrTx1 is the first compound characterized from the sea anemone Phymanthus crucifer, and it constitutes a novel ASIC inhibitor. This peptide was purified by chromatographic techniques and pharmacologically characterized on acid-sensing ion channels of mammalian neurons using patch-clamp techniques. PhcrTx1 inhibited ASIC currents with an IC50 of 100 nM. Edman degradation yielded a sequence of 32 amino acids residues, with a molecular mass of 3477 Da by MALDI-TOF. No similarity to known sea anemone peptides was found in protein databases. The computational analysis of Cys-pattern and secondary structure arrangement suggested that this is a structurally ICK (Inhibitor Cystine Knot)-type peptide, a scaffold that had not been found in sea anemones but in other venomous organisms. These results show that PhcrTx1 represents the first member of a new structural group of sea anemones toxins acting on ASICs. Also, this peptide constitutes a novel template for the development of drugs against pathologies related to ASICs function.

Keywords: animal toxin, inhibitor cystine knot, ion channel, sea anemone

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Authors: Koo Ja-Choon, Seok Hyun-Deok, Park So-Hee

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Even though developed countries have supported aid projects for restoring degraded and deforested mountain, recent North Korean authorities announced that North Korean forest is still very serious. Last 12 years, more than 16 thousand ha of forest were destroyed. Most of previous researches concluded that food and fuel problems should be solved for preventing people from deforesting and degrading forest in North Korea. It means that mountain restoration projects such as A/R(afforestation/reforestation) and REDD(Reducing Emissions from Deforestation and Forest Degradation) project should be implemented with the agroforestry and the forest tending project. Because agroforestry and the forest tending can provide people in the project area with foods and fuels, respectively. Especially, Agroforestry has been operated well with the support of Swiss agency of Development and cooperation since 2003. This paper aims to find the priority sites for mountain restoration project where all types of projects including agroforesty can be implemented simultaneously. We tried to find the primary counties where the areas of these activities were distributed widely and evenly. Recent spatial data of 186 counties representing altitude, gradient and crown density were collected from World Forest Watch. These 3 attributes were used to determine the type of activities; A/R, REDD, Agroforestry and forest tending project. Finally, we calculated the size of 4 activities in 186 counties by using GIS technique. Result shows that Chongjin in Hamgyeongbuk-do, Hoeryong in Hamgyeongbuk-do and Tongchang in Pyeonganbuk-do are on the highest priority of counties. Most of feasible counties whose value of richness and uniformity were greater than the average were located near the eastern coast of North Korea. South Korean government has not supported any aid projects in North Korea since 2010. Recently, South Korea is trying to continue the aid projects for North Korea. Forest project which is not affected by the political situation between North- and South- Korea can be considered as a priority activities. This result can be used when South Korean government determine the priority sites for North Korean mountain restoration project in near future.

Keywords: agroforestry, forest restoration project, GIS, North Korea, priority

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Authors: Omar Ali, Adesh Ramsubhag, Jayaraj Jayaraman

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Seaweed extracts have been reported as plant biostimulants which could be a safer, organic alternative to harsh pesticides. The incentive to use seaweed-based biostimulants is becoming paramount in sustainable agriculture. The current study, therefore, screened a commercial extract of A. nodosum in tomatoes, cultivated in Trinidad to showcase the multiple beneficial effects. Foliar treatment with an A. nodosum commercial extract led to significant increases in fruit yield and a significant reduction of incidence of bacterial spots and early blight diseases under both greenhouse and field conditions. Investigations were carried out to reveal the possible mechanisms of action of this biostimulant through defense enzyme assays and transcriptome profiling via RNA sequencing of tomato. Studies into disease control mechanisms by A. nodosum showed that the extract stimulated the activity of enzymes such as peroxidase, phenylalanine ammonia-lyase, chitinase, polyphenol oxidase, and β-1,3-glucanase. Additionally, the transcriptome survey revealed the upregulation and enrichment of genes responsible for the biosynthesis of growth hormones, defense enzymes, PR proteins and defense-related secondary metabolites, as well as genes involved in the nutrient mobilization, photosynthesis and primary and secondary metabolic pathways. The results of the transcriptome study also demonstrated the cross-talks between growth and defense responses, confirming the bioelicitor and biostimulant value of seaweed extracts in plants. These effects could potentially implicate the benefits of seaweed extract and validate its usage in sustainable crop production.

Keywords: A. nodosum, biostimulants, elicitor, enzymes, growth responses, seaweeds, tomato, transcriptome analysis

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Authors: Maryam Hamlehdar, Guillermo A. Narsilio

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To enhance the feasibility of utilising geothermal hot sedimentary aquifers (HSAs) for clean hydrogen production, one approach is the implementation of solar-integrated geothermal energy systems. This detailed modelling study conducts a thermo-economic assessment of an advanced Organic Rankine Cycle (ORC)-based hydrogen production system that uses low-temperature geothermal reservoirs, with a specific focus on hot sedimentary aquifers (HSAs) over a 30-year period. In the proposed hybrid system, solar-thermal energy is used to raise the water temperature extracted from the geothermal production well. This temperature increase leads to a higher steam output, powering the turbine and subsequently enhancing the electricity output for running the electrolyser. Thermodynamic modeling of a parabolic trough solar (PTS) collector is developed and integrated with modeling for a geothermal-based configuration. This configuration includes a closed regenerator cycle (CRC), proton exchange membrane (PEM) electrolyser, and thermoelectric generator (TEG). Following this, the study investigates the impact of solar energy use on the temperature enhancement of the geothermal reservoir. It assesses the resulting consequences on the lifecycle performance of the hydrogen production system in comparison with a standalone geothermal system. The results indicate that, with the appropriate solar collector area, a combined solar-geothermal hydrogen production system outperforms a standalone geothermal system in both cost and rate of production. These findings underscore a solar-assisted geothermal hybrid system holds the potential to generate lower-cost hydrogen with enhanced efficiency, thereby boosting the appeal of numerous low to medium-temperature geothermal sources for hydrogen production.

Keywords: clean hydrogen production, integrated solar-geothermal, low-temperature geothermal energy, numerical modelling

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Authors: Olalekan Adekola, Margaret Gatonye, Paul Orina

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The growing demand for farmed fish by underdeveloped and developing countries as a means of contributing positively towards eradication of hunger, food insecurity, and malnutrition for their fast growing populations has implications to the environment. Likewise, climate change poses both an immediate and future threat to local fish production with capture fisheries already experiencing a global decline. This not only raises fundamental questions concerning how aquaculture practices affect the environment, but also how ready are aquaculture farmers to adapt to climate related hazards. This paper assesses existing aquaculture practices and approaches to adapting to climate hazards in Kenya, where aquaculture has grown rapidly since the year 2009. The growth has seen rise in aquaculture set ups mainly along rivers and streams, importation of seed and feed and intensification with possible environmental implications. The aquaculture value chain in the context of climate change and their implication for practice is further investigated, and the strategies necessary for an improved implementation of resilient aquaculture system in Kenya is examined. Data for the study are collected from interviews, questionnaires, two workshops and document analysis. Despite acclaimed nutritional benefit of fish consumption in Kenya, poor management of effluents enriched with nitrogen, phosphorus, organic matter, and suspended solids has implications not just on the ecosystem, goods, and services, but is also potential source of resource-use conflicts especially in downstream communities and operators in the livestock, horticulture, and industrial sectors. The study concluded that aquaculture focuses on future orientation, climate resilient infrastructure, appropriate site selection and invest on biosafety as the key sustainable strategies against climate hazards.

Keywords: aquaculture, resilience, environment, strategies, Kenya

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Authors: Raviteja Chintala

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Water shortage in many areas of the world have predominantly increased the demand for efficient methods involved in the production of drinking water, So purification of water invoking cost effective and efficient methods is a challenging field of research. In this regard, Reverse osmosis membrane desalination of both seawater and inland brackish water is currently being deployed in various locations around the world. In the present work an attempt is made to integrate these existing technologies with novel method, Wherein carbon nanotubes at the lab scale are prepared which further replace activated carbon tubes being used traditionally. This has proven to enhance the efficiency of the water filter, Effectively neutralising most of the organic impurities. Furthermore, This ensures the reduction in TDS. Carbon nanotubes have wide range in scope of applications such as composite reinforcements, Field emitters, Sensors, Energy storage and energy conversion devices and catalysts support phases, Because of their unusual mechanical, Electrical, Thermal and structural properties. In particular, The large specific surface area, as well as the high chemical and thermal stability, Makes carbon nanotube an attractive adsorbent in waste water treatment. Carbon nanotubes are effective in eliminating these harmful media from water as an adsorbent. In this work, Candle soot method has been incorporated for the preparation of carbon nanotubes and mixed with activated charcoal in different compositions. The effect of composition change is monitored by using TDS measuring meter. As the composition of Nano carbon increases, The TDS of the water gradually decreases. In order to enhance the life time for carbon filter, Nano tubes are provided with larger surface area.

Keywords: TDS (Total Dissolved Solids), carbon nanotubes, water, candle soot

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Authors: Maydariana Ayuningtyas, Bambang Riyanto, Akhiruddin Maddu

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Industrial waste of crustacean shells, such as shrimp and crab, has been considered as one of the major issues contributing to environmental pollution. The waste processing mechanisms to form new, practical substances with added value have been developed. Chitosan, a derived matter from chitin, which is obtained from crab and shrimp shells, performs prodigiously in broad range applications. A chitosan composite-based diaphragm is a new inspiration in fiber optic acoustic sensor advancement. Elastic modulus, dynamic response, and sensitivity to acoustic wave of chitosan-based composite film contribute great potentials of organic-based sound-detecting material. The objective of this research was to develop chitosan diaphragm application in fiber optic microphone system. The formulation was conducted by blending 5% polyvinyl alcohol (PVA) solution with dissolved chitosan at 0%, 1% and 2% in 1:1 ratio, respectively. Composite diaphragms were characterized for the morphological and mechanical properties to predict the desired acoustic sensor sensitivity. The composite with 2% chitosan indicated optimum performance with 242.55 µm thickness, 67.9% relative humidity, and 29-76% light transmittance. The Young’s modulus of 2%-chitosan composite material was 4.89×104 N/m2, which generated the voltage amplitude of 0.013V and performed sensitivity of 3.28 mV/Pa at 1 kHz. Based on the results above, chitosan from crustacean shell waste can be considered as a viable alternative material for fiber optic acoustic sensor sensing pad development. Further, the research in chitosan utilisation is proposed as novel optical microphone development in anthropogenic noise controlling effort for environmental and biodiversity conservation.

Keywords: acoustic sensor, chitosan, composite, crab shell, diaphragm, waste utilisation

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Authors: Clara Franch de la Cal, Christopher J Morris, Michael McArthur

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Cystic fibrosis (CF) is an autosomal recessive genetic disorder characterized by abnormal transport of chloride and sodium across the lung epithelium, leading to thick and viscous secretions. Within which CF patients suffer from repeated bacterial pulmonary infections, with Pseudomonas aeru-ginosa (PA) eliciting the greatest inflammatory response, causing an irreversible loss of lung func-tion that determines morbidity and mortality. The cell wall of PA is a permeability barrier to many antibacterials and the rise of Mutli-Drug Resistant strains (MDR) is eroding the efficacy of the few remaining clinical options. In addition when PA infection becomes established it forms an antibi-otic-resistant biofilm, embedded in which are slow growing cells that are refractive to drug treat-ment. Making the development of new antibacterials a major challenge. This work describes the development of new type of nanoparticulate oligonucleotide antibacterial capable of tackling PA infections, including MDR strains. It is being developed to both block growth and prevent biofilm formation. These oligonucleotide therapeutics, Transcription Factor Decoys (TFD), act on novel genomic targets by capturing key regulatory proteins to block essential bacterial genes and defeat infection. They have been successfully transfected into a wide range of pathogenic bacteria, both in vitro and in vivo, using a proprietary delivery technology. The surfactant used self-assembles with TFD to form a nanoparticle stable in biological fluids, which protects the TFD from degradation and preferentially transfects prokaryotic membranes. Key challenges are to adapt the nanoparticle so it is active against PA in the context of biofilms and to formulate it for administration by inhalation. This would allow the drug to be delivered to the respiratory tract, thereby achieving drug concentrations sufficient to eradicate the pathogenic organisms at the site of infection.

Keywords: antibacterials, transcriptional factor decoys (TFDs), pseudomonas aeruginosa

Procedia PDF Downloads 284

Authors: Hamidreza Mehrabi, Mandana Rezayee

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The coated seed process is from amplifier ways that stick various materials on the outer surface of the seeds that minimize the negative environmental effects and increase the ability of Plant establishment. This study was done to assess the effects of coated seed on the germination speed of Astragalus adscendens in different conditions of drought stress and planting depth as it was conducted with a completely randomized factorial design with four replications. treatments of covering material was used in Four non coating levels (NC), mineral-based coating (CC), organic - based coating (OC) hydro gel-based coating (HC) ; treatment of moisture percent used in three levels of dried soil content, treatments of planting depth in two surfaces of planting and three times of the seed diameter was 9%, 14% and 21 % respectively. During the test, it was evaluated the germination speed attribute. The main results showed that moisture treatments and planting depth at a surface of 1% (P <0/01) was significant and has no significant effect of treatment materials. Also, In examining of the interaction between type of covering material and soil moisture were not observed significant differences for germination speed between covering treatments and controls covering, but there was a significant difference between treatments in 9% and 21%. Although in examining the triple interaction, increasing moisture and planting depth enhanced the speed of germination process, but it was not significant statistically, while it has made important differences in terms of description; because it had not growth in the moisture level of 9% and shallow cultivation (high stress). However, treatment of covered materials growth has developed significantly, so it can be useful in enhancing plant performance.

Keywords: seed coating, soil moisture, sowing depth, germination percentage

Procedia PDF Downloads 274

Authors: P. Acosta-Santamaría, A. Ibatá-Soto, A. López-Vásquez

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Organic compounds in wastewaters coming from textile and pharmaceutical industry generated multiple harmful effects on the environment and the human health. One of them is the methyl orange (MeO), an azoic dye considered to be a recalcitrant compound. The heterogeneous photocatalysis emerges as an alternative for treating this type of hazardous compounds, through the generation of OH radicals using radiation and a semiconductor oxide. According to the author’s knowledge, catalysts such as TiO₂ doped with metals show high efficiency in degrading MeO; however, this presents economic limitations on industrial scale. Black sand can be considered as a naturally doped catalyst because in its structure is common to find compounds such as titanium, iron and aluminum oxides, also elements such as zircon, cadmium, manganese, etc. This study reports the photocatalytic activity of the mineral black sand used as semiconductor in the discoloration of MeO by oxidation and reduction photocatalytic techniques. For this, magnetic composites from the mineral were prepared (RM, M1, M2 and NM) and their activity were tested through MeO discoloration while TiO₂ was used as reference. For the fractions, chemical, morphological and structural characterizations were performed using Scanning Electron Microscopy with Energy Dispersive X-Ray (SEM-EDX), X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) analysis. M2 fraction showed higher MeO discoloration (93%) in oxidation conditions at pH 2 and it could be due to the presence of ferric oxides. However, the best result to reduction process was using M1 fraction (20%) at pH 2, which contains a higher titanium percentage. In the first process, hydrogen peroxide (H₂O₂) was used as electron donor agent. According to the results, black sand mineral can be used as natural semiconductor in photocatalytic process. It could be considered as a photocatalyst precursor in such processes, due to its low cost and easy access.

Keywords: black sand mineral, methyl orange, oxidation, photocatalysis, reduction

Procedia PDF Downloads 383

Authors: Emine Yılmaz, Serap Fındık

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Baker’s yeast industry uses molasses as a raw material. Molasses is end product of sugar industry. Wastewater from molasses processing presents large amount of coloured substances that give dark brown color and high organic load to the effluents. The main coloured compounds are known as melanoidins. Melanoidins are product of Maillard reaction between amino acid and carbonyl groups in molasses. Dark colour prevents sunlight penetration and reduces photosynthetic activity and dissolved oxygen level of surface waters. Various methods like biological processes (aerobic and anaerobic), ozonation, wet air oxidation, coagulation/flocculation are used to treatment of baker’s yeast effluent. Before effluent is discharged adequate treatment is imperative. In addition to this, increasingly stringent environmental regulations are forcing distilleries to improve existing treatment and also to find alternative methods of effluent management or combination of treatment methods. Sonochemical oxidation is one of the alternative methods. Sonochemical oxidation employs ultrasound resulting in cavitation phenomena. In this study, decolorization of baker’s yeast effluent was investigated by using ultrasound. Baker’s yeast effluent was supplied from a factory which is located in the north of Turkey. An ultrasonic homogenizator used for this study. Its operating frequency is 20 kHz. TiO2-ZnO catalyst has been used as sonocatalyst. The effects of molar proportion of TiO2-ZnO, calcination temperature and time, catalyst amount were investigated on the decolorization of baker’s yeast effluent. The results showed that prepared composite TiO2-ZnO with 4:1 molar proportion treated at 700°C for 90 min provides better result. Initial decolorization rate at 15 min is 3% without catalyst, 14,5% with catalyst treated at 700°C for 90 min respectively.

Keywords: baker’s yeast effluent, decolorization, sonocatalyst, ultrasound

Procedia PDF Downloads 474

Authors: Saleh Kasiri Bidhendi, Shiva Tashakori

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With the increasing application of six-wheel robots in various industries, including agriculture and environmental monitoring, there is a growing demand for efficient and reliable control systems that can improve manoeuvrability and at the same time reduce energy consumption. Moving on uneven terrains, various factors such as obstacles or soil heterogeneity can cause the robot to slip. There is limited research addressing this issue. Although the robot is supposed to track a predetermined path, sudden lateral deviation necessitates path planning. To further address this issue, explicit steering is added by activating actuators on steerable wheels, while the SMC controller still commands differential traction forces on all wheels. This integration improves energy efficiency and obstacle traversability while maintaining the merits of skid-steering, such as tight turning manoeuvrability. However, achieving the desired steer angles presents certain challenges. Inverse kinematics was initially employed to achieve the needed steering angles from the desired position, but this approach led to excessive steering without yawing the body. Switching to desired velocity values instead of position limited over-steering but caused zero lateral velocity on horizontal paths, which was problematic for unforeseen skidding. To overcome this, a proportional controller has been employed, using lateral error as its input and providing a proportional yaw angle as output, the P-controller contributes to modifying the steering angles. The controller's robustness has been verified through sensitivity analyses under critical speeds and turning radius conditions. Our findings offer valuable insights into designing more efficient steering controls for rocker-bogie mechanisms in challenging situations, emphasizing the importance of reducing energy¬ consumption.

Keywords: six-wheel robots, inverse kinematics, integrated steering, path following, manoeuvrability, energy efficiency, uneven terrains

Procedia PDF Downloads 32

Authors: Nedal N. Marei, Nashaat Nassar

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Many treatment techniques have been used to remove the soluble pollutants from wastewater as; dyes and metal ions which could be found in rich amount in the used water of the textile and tanneries industry. The effluents from these industries are complex, containing a wide variety of dyes and other contaminants, such as dispersants, acids, bases, salts, detergents, humectants, oxidants, and others. These techniques can be divided into physical, chemical, and biological methods. Adsorption has been developed as an efficient method for the removal of heavy metals from contaminated water and soil. It is now recognized as an effective method for the removal of both organic and inorganic pollutants from wastewaters. Nanosize materials are new functional materials, which offer high surface area and have come up as effective adsorbents. Nano alumina is one of the most important ceramic materials widely used as an electrical insulator, presenting exceptionally high resistance to chemical agents, as well as giving excellent performance as a catalyst for many chemical reactions, in microelectronic, membrane applications, and water and wastewater treatment. In this study, methylene blue (MB) dye has been used as model dye of textile wastewater in order to synthesize a synthetic MB wastewater. NiO nanoparticles were added in small percentage in the sand packed bed adsorption columns to remove the MB from the synthetic textile wastewater. Moreover, different parameters have been evaluated; flow of the synthetic wastewater, pH, height of the bed, percentage of the NiO to the sand in the packed material. Different mathematical models where employed to find the proper model which describe the experimental data and help to analyze the mechanism of the MB adsorption. This study will provide good understanding of the dyes adsorption using metal oxide nanoparticles in the classical sand bed.

Keywords: adsorption, column, nanoparticles, methylene

Procedia PDF Downloads 269

Authors: Juni C. Kim, Anna R. Robuck, Douglas I. Walker

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The human exposome, which includes chemical exposures over the lifetime and their effects, is now recognized as an important measure for understanding human health; however, the complexity of the data makes the identification of environmental chemicals challenging. The goal of our project was to establish a computational workflow for the improved identification of environmental pollutants containing chlorine or bromine. Using the “pattern. search” function available in the R package NonTarget, we wrote a multifunctional script that searches mass spectral clusters from untargeted gas-chromatography high-resolution mass spectrometry (GC-HRMS) for the presence of spectra consistent with chlorine and bromine-containing organic compounds. The “pattern. search” function was incorporated into a different function that allows the evaluation of clusters containing multiple analyte fragments, has multi-core support, and provides a simplified output identifying listing compounds containing chlorine and/or bromine. The new function was able to process 46,000 spectral clusters in under 8 seconds and identified over 150 potential halogenated spectra. We next applied our function to a deidentified dataset from patients diagnosed with primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and healthy controls. Twenty-two spectra corresponded to potential halogenated compounds in the PSC and PBC dataset, including six significantly different in PBC patients, while four differed in PSC patients. We have developed an improved algorithm for detecting halogenated compounds in GC-HRMS data, providing a strategy for prioritizing exposures in the study of human disease.

Keywords: exposome, metabolome, computational metabolomics, high-resolution mass spectrometry, exposure, pollutants

Procedia PDF Downloads 138

Authors: Luis Alvarado, Victor Poblete, Isaac Gonzalez, Yetzabeth Gonzalez

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In MIREX 2016 (http://www.music-ir.org/mirex), the deep neural network (DNN)-Deep Chroma Extractor, proposed by Korzeniowski and Wiedmer, reached the highest score in an audio chord recognition task. In the present paper, this tool is assessed under acoustic reverberant environments and distinct source-microphone distances. The evaluation dataset comprises The Beatles and Queen datasets. These datasets are sequentially re-recorded with a single microphone in a real reverberant chamber at four reverberation times (0 -anechoic-, 1, 2, and 3 s, approximately), as well as four source-microphone distances (32, 64, 128, and 256 cm). It is expected that the performance of the trained DNN will dramatically decrease under these acoustic conditions with signals degraded by room reverberation and distance to the source. Recently, the effect of the bio-inspired Locally-Normalized Cepstral Coefficients (LNCC), has been assessed in a text independent speaker verification task using speech signals degraded by additive noise at different signal-to-noise ratios with variations of recording distance, and it has also been assessed under reverberant conditions with variations of recording distance. LNCC showed a performance so high as the state-of-the-art Mel Frequency Cepstral Coefficient filters. Based on these results, this paper proposes a variation of locally-normalized triangular filters called Locally-Normalized Quarter Tone (LNQT) filters. By using the LNQT spectrogram, robustness improvements of the trained Deep Chroma Extractor are expected, compared with classical triangular filters, and thus compensating the music signal degradation improving the accuracy of the chord recognition system.

Keywords: chord recognition, deep neural networks, feature extraction, music information retrieval

Procedia PDF Downloads 232

Authors: J. Dharmaraj, C. Gunasekaran

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Invertebrates are the reliable ecological indicators of disturbance of the forest ecosystems and they respond to environment changes more quickly than other fauna. Among these the terrestrial invertebrates are vital to functioning ecosystems, contributing to processes such as decomposition, nutrient cycling and soil fertility. The natural ecosystems of the forests have been subject to various types of disturbances, which lead to decline of flora and fauna. The comparative diversity of micro-arthropods in natural forest, wattle plantation and eucalyptus plantations were studied in Nilgiris. The study area was divided in to five major sites (Emerald (Site-I), Thalaikundha (Site-II), Kodapmund (Site-III), Aravankad (Site-IV), Kattabettu (Site-V). The research was conducted during period from March 2014 to August 2014. The leaf and soil samples were collected and isolated by using Berlese funnel extraction methods. Specimens were isolated and identified according to their morphology (Balogh 1972). In the present study results clearly showed the variation in soil pH, NPK (Major Nutrients) and organic carbon among the study sites. The chemical components of the leaf litters of the plantation decreased the diversity of micro-arthropods and decomposition rate leads to low amount of carbon and other nutrients present in the soil. Moreover eucalyptus and wattle plantations decreases the availability of the ground water source to other plantations and micro-arthropods and hences affects the soil fertility. Hence, the present study suggests to minimize the growth of wattle and eucalyptus tree plantations in the natural areas which may help to reduce the decline of forests.

Keywords: micro-arthropods, assemblage, berlese funnel, morphology, NPK, nilgiris

Procedia PDF Downloads 309

Authors: Marwa Brahim, Nicolas Brosse, Nadia Boussetta, Nabil Grimi, Eugene Vorobiev

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Rapeseed plant is an established product in France which is mainly dedicated to oil production. However, the economic potential of residues from this industry (rapeseed hulls, rapeseed cake, rapeseed straw etc.), has not been fully exploited. Currently, only low-grade applications are found in the market. As a consequence, it was deemed of interest to develop a technological platform aiming to convert rapeseed residues into value- added products. Specifically, a focus is given on the conversion of rapeseed straw into valuable molecules (e.g. lignin, glucose). Existing pretreatment technologies have many drawbacks mainly the production of sugar degradation products that limit the effectiveness of saccharification and fermentation steps in the overall scheme of the lignocellulosic biorefinery. In addition, the viability of fractionation strategies is a challenge in an environmental context increasingly standardized. Hence, the need to find cleaner alternatives with comparable efficiency by implementing physical phenomena that could destabilize the structural integrity of biomass without necessarily using chemical solvents. To meet environmental standards increasingly stringent, the present work aims to study the new pretreatment strategies involving lower consumption of chemicals with an attenuation of the severity of the treatment. These strategies consist on coupling physical treatments either high voltage electrical discharges or ultrasounds to conventional chemical pretreatments (soda and organosolv). Ultrasounds treatment is based on the cavitation phenomenon, and high voltage electrical discharges cause an electrical breakdown accompanied by many secondary phenomena. The choice of process was based on a technological feasibility study taking into account the economic profitability of the whole chain after products valorization. Priority was given to sugars valorization into bioethanol and lignin sale.

Keywords: high voltage electrical discharges, organosolv, pretreatment strategies, rapeseed straw, soda, ultrasounds

Procedia PDF Downloads 363

Authors: Ahmed Saeed, Sadok Sassi, Mohammad Roshun

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Gears are important components with a vital role in many rotating machines. One of the common gear failure causes is tooth fatigue crack; however, its early detection is still a challenging task. The objective of this study is to develop a numerical model that simulates the effect of teeth cracks on the resulting gears vibrations and permits consequently to perform an early fault detection. In contrast to other published papers, this work incorporates the possibility of multiple simultaneous cracks with different depths. As cracks alter significantly the stiffness of the tooth, finite element software is used to determine the stiffness variation with respect to the angular position, for different combinations of crack orientation and depth. A simplified six degrees of freedom nonlinear lumped parameter model of a one-stage spur gear system is proposed to study the vibration with and without cracks. The model developed for calculating the stiffness with the crack permitted to update the physical parameters of the second-degree-of-freedom equations of motions describing the vibration of the gearbox. The vibration simulation results of the gearbox were by obtained using Simulink/Matlab. The effect of one crack with different levels was studied thoroughly. The change in the mesh stiffness and the vibration response were found to be consistent with previously published works. In addition, various statistical time domain parameters were considered. They showed different degrees of sensitivity toward the crack depth. Multiple cracks were also introduced at different locations and the vibration response along with the statistical parameters were obtained again for a general case of degradation (increase in crack depth, crack number and crack locations). It was found that although some parameters increase in value as the deterioration level increases, they show almost no change or even decrease when the number of cracks increases. Therefore, the use of any statistical parameters could be misleading if not considered in an appropriate way.

Keywords: Spur gear, cracked tooth, numerical simulation, time-domain parameters

Procedia PDF Downloads 266

Authors: Suheyla Kocaman, Gulnare Ahmetli, Alaaddin Cerit, Alize Yucel, Merve Gozukucuk

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Shell wastes represent a considerable quantity of byproducts in the shellfish aquaculture. From the viewpoint of ecofriendly and economical disposal, it is highly desirable to convert these residues into high value-added products for industrial applications. So far, the utilization of shell wastes was confined at relatively lower levels, e.g. wastewater decontaminant, soil conditioner, fertilizer constituent, feed additive and liming agent. Shell wastes consist of calcium carbonate and organic matrices, with the former accounting for 95-99% by weight. Being the richest source of biogenic CaCO₃, shell wastes are suitable to prepare high purity CaCO₃ powders, which have been extensively applied in various industrial products, such as paper, rubber, paints and pharmaceuticals. Furthermore, the shell waste could be further processed to be the filler of polymer composites. This paper presents a study on the potential use of mussel shell waste as biofiller to produce the composite materials with different epoxy matrices, such as bisphenol-A type, CTBN modified and polyurethane modified epoxy resins. Morphology and mechanical properties of shell particles reinforced epoxy composites were evaluated to assess the possibility of using it as a new material. The effects of shell particle content on the mechanical properties of the composites were investigated. It was shown that in all composites, the tensile strength and Young’s modulus values increase with the increase of mussel shell particles content from 10 wt% to 50 wt%, while the elongation at break decreased, compared to pure epoxy resin. The highest Young’s modulus values were determined for bisphenol-A type epoxy composites.

Keywords: biocomposite, epoxy resin, mussel shell, mechanical properties

Procedia PDF Downloads 314