Search results for: nitrogen footprint
712 Estimating Directional Shadow Prices of Air Pollutant Emissions by Transportation Modes
Authors: Huey-Kuo Chen
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This paper applies directional marginal productivity model to study the shadow price of emissions by transportation modes in the years of 2011 and 2013 with the aim to provide a reference for policy makers to improve the emission of pollutants. One input variable (i.e., energy consumption), one desirable output variable (i.e., vehicle kilometers traveled) and three undesirable output variables (i.e., carbon dioxide, sulfur oxides and nitrogen oxides) generated by road transportation modes were used to evaluate directional marginal productivity and directional shadow price for 18 transportation modes. The results show that the directional shadow price (DSP) of SOx is much higher than CO2 and NOx. Nevertheless, the emission of CO2 is the largest among the three kinds of pollutants. To improve the air quality, the government should pay more attention to the emission of CO2 and apply the alternative solution such as promoting public transportation and subsidizing electric vehicles to reduce the use of private vehicles.Keywords: marginal productivity, road transportation modes, shadow price, undesirable outputs
Procedia PDF Downloads 148711 Digital Transformation and Environmental Disclosure in Industrial Firms: The Moderating Role of the Top Management Team
Authors: Yongxin Chen, Min Zhang
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As industrial enterprises are the primary source of national pollution, environmental information disclosure is a crucial way to demonstrate to stakeholders the work they have done in fulfilling their environmental responsibilities and accepting social supervision. In the era of the digital economy, many companies, actively embracing the opportunities that come with digital transformation, have begun to apply digital technology to information collection and disclosure within the enterprise. However, less is known about the relationship between digital transformation and environmental disclosure. This study investigates how enterprise digital transformation affects environmental disclosure in 643 Chinese industrial companies, according to information processing theory. What is intriguing is that the depth (size) and breadth (diversity) of environmental disclosure linearly increase with the rise in the collection, processing, and analytical capabilities in the digital transformation process. However, the volume of data will grow exponentially, leading to a marginal increase in the economic and environmental costs of utilizing, storing, and managing data. In our empirical findings, linearly increasing benefits and marginal costs create a unique inverted U-shaped relationship between the degree of digital transformation and environmental disclosure in the Chinese industrial sector. Besides, based on the upper echelons theory, we also propose that the top management team with high stability and managerial capabilities will invest more effort and expense into improving environmental disclosure quality, lowering the carbon footprint caused by digital technology, maintaining data security etc. In both these contexts, the increasing marginal cost curves would become steeper, weakening the inverted U-shaped slope between DT and ED.Keywords: digital transformation, environmental disclosure, the top management team, information processing theory, upper echelon theory
Procedia PDF Downloads 142710 Study of Dual Fuel Engine as Environmentally Friendly Engine
Authors: Nilam S. Octaviani, Semin
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The diesel engine is an internal combustion engine that uses compressed air to combust. The diesel engines are widely used in the world because it has the most excellent combustion efficiency than other types of internal combustion engine. However, the exhaust emissions of it produce pollutants that are harmful to human health and the environment. Therefore, natural gas used as an alternative fuel using on compression ignition engine to respond those environment issues. This paper aims to discuss the comparison of the technical characteristics and exhaust gases emission from conventional diesel engine and dual fuel diesel engine. According to the study, the dual fuel engine applications have a lower compression pressure and has longer ignition delay compared with normal diesel mode. The engine power is decreased at dual fuel mode. However, the exhaust gases emission on dual fuel engine significantly reduce the nitrogen oxide (NOx), carbon dioxide (CO2) and particular metter (PM) emissions.Keywords: diesel engine, dual fuel diesel engine, emission reduction, technical characteristics
Procedia PDF Downloads 307709 Construction and Application of Zr-MCM41 Nanoreactors as Highly Active and Efficiently Catalyst in the Synthesis of Biginelli-Type Compounds
Authors: Zohreh Derikvand
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Nanoreactors Zr-MCM-41were prepared via the reaction of ZrOCl2, Fumed silica, sodium hydroxide and cethyltrimethyl ammonium bromide under hydrothermal condition. The prepared nanoreactors were characterized by FT-IR spectroscopy, X-ray diffraction (XRD), Scanning electron micrographs (SEM) and nitrogen adsorption-desorption. The XRD pattern of Zr-MCM-41 exhibits a high-intensity (100) and two low-intensity reflections (110 and 200) which are characteristic of hexagonal structure, exhibiting the long-range order and good textural uniformity of mesoporous structure. Based on the green chemistry approach, we report an efficient and environmentally benign protocol to study the catalytic activity of Zr-MCM-41 in the Biginelli type reactions initially. Nanoreactors Zr-MCM-41 were used as highly recoverable and reusable catalyst for synthesis of 3,4-dihydropyrimidin-2(1H)-one, octahydroquinazolinone, benzimidazolo-quinazolineone and 4,6-diarylpyrimidin-2(1H)-one. The methodology offers several advantages such as short reaction time, high yields and simple operation. The catalyst was active up to three cycles.Keywords: Zr-MCM-41 nanoreactors, Biginelli like reactions, 3, 4-dihydropyrimidin-2(1H)-ones, ctahydroquinazolinones
Procedia PDF Downloads 206708 Assessing the Legacy Effects of Wildfire on Eucalypt Canopy Structure of South Eastern Australia
Authors: Yogendra K. Karna, Lauren T. Bennett
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Fire-tolerant eucalypt forests are one of the major forest ecosystems of south-eastern Australia and thought to be highly resistant to frequent high severity wildfires. However, the impact of different severity wildfires on the canopy structure of fire-tolerant forest type is under-studied, and there are significant knowledge gaps in relation to the assessment of tree and stand level canopy structural dynamics and recovery after fire. Assessment of canopy structure is a complex task involving accurate measurements of the horizontal and vertical arrangement of the canopy in space and time. This study examined the utility of multitemporal, small-footprint lidar data to describe the changes in the horizontal and vertical canopy structure of fire-tolerant eucalypt forests seven years after wildfire of different severities from the tree to stand level. Extensive ground measurements were carried out in four severity classes to describe and validate canopy cover and height metrics as they change after wildfire. Several metrics such as crown height and width, crown base height and clumpiness of crown were assessed at tree and stand level using several individual tree top detection and measurement algorithm. Persistent effects of high severity fire 8 years after both on tree crowns and stand canopy were observed. High severity fire increased the crown depth but decreased the crown projective cover leading to more open canopy.Keywords: canopy gaps, canopy structure, crown architecture, crown projective cover, multi-temporal lidar, wildfire severity
Procedia PDF Downloads 175707 Characterization of Chemically Deposited CdS Thin Films Annealed in Different Atmospheres
Authors: J. Pantoja Enríquez, G. P. Hernández, G. I. Duharte, X. Mathew, J. Moreira, P. J. Sebastian
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Cadmium sulfide films were deposited onto glass substrates by chemical bath deposition (CBD) from a bath containing cadmium acetate, ammonium acetate, thiourea, and ammonium hydroxide. The CdS thin films were annealed in air, argon, hydrogen and nitrogen for 1 h at various temperatures (300, 350, 400, 450 and 500 °C). The changes in optical and electrical properties of annealed treated CdS thin films were analyzed. The results showed that, the band-gap and resistivity depend on the post-deposition annealing atmosphere and temperatures. Thus, it was found that these properties of the films, were found to be affected by various processes with opposite effects, some beneficial and others unfavorable. The energy gap and resistivity for different annealing atmospheres was seen to oscillate by thermal annealing. Recrystallization, oxidation, surface passivation, sublimation and materials evaporation were found the main factors of the heat-treatment process responsible for this oscillating behavior. Annealing over 400 °C was seen to degrade the optical and electrical properties of the film.Keywords: cds, thin films, annealing, optical, electrical properties
Procedia PDF Downloads 510706 Thermal Regeneration of CO2 Spent Palm Shell-Polyetheretherketone Activated Carbon Sorbents
Authors: Usman D. Hamza, Noor S. Nasri, Mohammed Jibril, Husna M. Zain
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Activated carbons (M4P0, M4P2, and M5P2) used in this research were produced from palm shell and polyetherether ketone (PEEK) via carbonization, impregnation, and microwave activation. The adsorption/desorption process was carried out using static volumetric adsorption. Regeneration is important in the overall economy of the process and waste minimization. This work focuses on the thermal regeneration of the CO2 exhausted microwave activated carbons. The regeneration strategy adopted was thermal with nitrogen purge desorption with N2 feed flow rate of 20 ml/min for 1 h at atmospheric pressure followed by drying at 1500C. Seven successive adsorption/regeneration processes were carried out on the material. It was found that after seven adsorption regeneration cycles; the regeneration efficiency (RE) for CO2 activated carbon from palm shell only (M4P0) was more than 90% while that of hybrid palm shell-PEEK (M4P2, M5P2) was above 95%. The cyclic adsorption and regeneration shows the stability of the adsorbent materials.Keywords: activated carbon, palm shell-PEEK, regeneration, thermal
Procedia PDF Downloads 488705 A Density Functional Theory Study of Metal-Porphyrin Graphene for CO2 Hydration
Authors: Manju Verma, Parag A. Deshpande
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Electronic structure calculations of hydrogen terminated metal-porphyrin graphene were carried out to explore the catalytic activity for CO2 hydration reaction. A ruthenium atom was substituted in place of carbon atom of graphene and ruthenium chelated carbon atoms were replaced by four nitrogen atoms in metal-porphyrin graphene system. Ruthenium atom created the active site for CO2 hydration reaction. Ruthenium-porphyrin graphene followed the mechanism of carbonic anhydrase enzyme for CO2 conversion to HCO3- ion. CO2 hydration reaction over ruthenium-porphyrin graphene proceeded via the elementary steps: OH- formation from H2O dissociation, CO2 bending in presence of nucleophilic attack of OH- ion, HCO3- ion formation from proton migration, HCO3- ion desorption by H2O addition. Proton transfer to yield HCO3- ion was observed as a rate limiting step from free energy landscape.Keywords: ruthenium-porphyrin graphene, CO2 hydration, carbonic anhydrase, heterogeneous catalyst, density functional theory
Procedia PDF Downloads 261704 Adsorption of Phenolic Compounds on Activated Carbon DSAC36-24
Authors: Khaoula Hidouri, Ali Benhmidene, Bechir Chouachi, Dhananjay R. Mishra, Ammar Houas
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Activated carbon DSAC36-24 iy is adsorbent materials, characterized by a specific surface area of 548.13 m²g⁻¹. Their manufacture uses the natural raw materials like the nucleus of dates. In this study the treatment is done in two stages: A chemical treatment by H3PO4 followed by a physical treatment under nitrogen for 1 hour then under stream of CO2 for 24 hours. A characterization of the various parameters was determined such as the measurement of the specific surface area, determination of pHPZC, bulk density, iodine value. The study of the adsorption of organic molecules (hydroquinone, paranitrophenol, 2,4-dinitrophenol, 2,4,6-trinitrophenol) indicates that the adsorption phenomena are essentially due to the van der Waals interaction. In the case of organic molecules carrying the polar substituents, the existence of hydrogen bonds is also proved by the donor-acceptor forces. The study of the pH effect was done with modeling by different models (Langmuir, Freundlich, Langmuir-Freundlich, Redlich-Peterson), a kinetic treatment is also followed by the application of Lagergren, Weber, Macky.Keywords: adsoprtion ishoterms, adsorption kinetics, DSAC36-24, organic molecule
Procedia PDF Downloads 279703 Numerical Simulation of Urea Water Solution Evaporation Behavior inside the Diesel Selective Catalytic Reduction System
Authors: Kumaresh Selvakumar, Man Young Kim
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Selective catalytic reduction (SCR) converts the nitrogen oxides with the aid of a catalyst by adding aqueous urea into the exhaust stream. In this work, the urea water droplets are sprayed over the exhaust gases by treating with Lagrangian particle tracking. The evaporation of ammonia from a single droplet of urea water solution is investigated computationally by convection-diffusion controlled model. The conversion to ammonia due to thermolysis of urea water droplets is measured downstream at different sections using finite rate/eddy dissipation model. In this paper, the mixer installed at the upstream enhances the distribution of ammonia over the entire domain which is calculated for different time steps. Calculations are made within the respective duration such that the complete decomposition of urea is possible at a much shorter residence time.Keywords: convection-diffusion controlled model, lagrangian particle tracking, selective catalytic reduction, thermolysis
Procedia PDF Downloads 406702 Ceramic Composites and Its Applications for Pb Adsorption
Authors: C. L. Popa, S. L. Iconaru, A. Costescu, C. S. Ciobanu, M. Motelica Heino, R. Guegan, D. Predoi
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Surface functionalization of ceramic composites with a special focus on tetraethyl orthosilicate (TEOS) and hydroxyapatite (HAp) is discoursed. Mesoporous ceramic HAp-TEOS composites were prepared by the incorporation of hydroxyapatite into tetraethyl orthosilicate by sol-gel method. The resulting samples were analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, and Raman spectroscopy and nitrogen physisorption. The removal of Pb2+ ions from aqueous solutions was evaluated using Atomic Absorbtion Spectroscopy (AAS). Removal experiments of Pb2+ ions were carried out in aqueous solutions with controlled Pb2+ at pH ~ 3 and pH ~ 5. After removal experiment of Pb2+ at pH 3 and pH 5, porous hydroxyapatite nanoparticles is transformed into PbHAp_3 and PbHAp_5 via the adsorption of Pb2+ ions followed by the cation exchange reaction. The diffraction patterns show that THAp nanoparticles were successfully coated with teos without any structural changes. On the other, the AAS analysis showed that THAp can be useful in the removal Pb2+ from water contaminated.Keywords: teos, hydroxyapatite, environment applications, biosystems engineering
Procedia PDF Downloads 384701 Vitrification-Based Cryopreservation of Phalaenopsis cornu-Cervi (Breda) Blume & Rchb. f. Protocorms
Authors: Suphat Rittirat, Sutha Klaocheed, Somporn Prasertsongskun, Kanchit Thammasiri
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Protocorms of Phalaenopsis cornu-cervi (Breda) Blume & Rchb. f. were successfully cryopreserved using a vitrification method. Two-month old protocorms at GI 4 stage were precultured in liquid MS medium supplemented with different concentrations of sucrose (0.3, 0.5, 0.7, 0.9 and 1.2 M) at 25±1°C for 2 days on an orbital shaker at 110 rpm. The protocorms were treated with loading solution (2 M glycerol plus 0.4 M sucrose) for 20 minutes at 25±1°C. Then, the protocorms were sufficiently dehydrated with vitrification solution (plant vitrification solution 2, PVS2) for various times (0, 30, 60, 90 and 120 minutes) at 25±1°C and stored in liquid nitrogen for 1 day. After rapid thawing in water bath at 40°C for 2 minutes, the explants were washed by MS liquid medium containing 0.5 ml of 1.2 M sucrose for 20 minutes. The results shown that the protocorms were precultured in liquid MS medium containing 0.5 M sucrose and dehydrated with vitrification solution for 60 minutes had the highest survival percentage of protocorm at 31±1.0 % as measured by Evan’s blue. No survival rate of protocorms was found without vitrification treatments.Keywords: protocorms, cryopreservation, Phalaenopsis cornu-cervi, vitrification
Procedia PDF Downloads 363700 A Descriptive Study on Micro Living and Its Importance over Large Houses by Understanding Various Scenarios and Case Studies
Authors: Belal Neazi
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'Larger Houses Consume More Resources’ – both in construction and during operation. The most important aspect of smaller homes is that it uses less electricity and fuel for construction and maintenance. Here, an urban interpretation of the contemporary minimal existence movement is explained. In an attempt to restrict urban decay and to encourage inner-city renewal, the Tiny House principles are interpreted as alternative ways of dwelling in urban neighbourhoods. These tiny houses are usually pretty different from each other in interior planning, but almost similar in size. The disadvantage of large homes came up when people were asked to vacate as they were not able to pay the massive amount of mortgages. This made them reconsider their housing situation and discover the ideas of minimalism and the general rising inclination in environmental awareness that serve as the basis for the tiny house movement. One of the largest benefits of inhabiting a tiny house is the decrease in carbon footprint. Also, to increase social behaviour and freedom. It’s better for the environmental concern, financial concerns, and desire for more time and freedom. Examples of the tiny house village which are sustaining homeless population and the use of different reclaimed materials for the construction of these tiny houses are explained in the paper. It is proposed in the paper, that these houses will reflect the diversity while proposing an alternative model for the rehabilitation of decaying row-homes and the renewal of fading communities. The core objective is to design small or micro spaces for the economically backward people of the place and increase their social behaviour and freedom. Also, it’s better for the environmental concern, financial concerns, and desire for more time and freedom.Keywords: city renewal, environmental concern, micro-living, tiny house
Procedia PDF Downloads 182699 The Security Trade-Offs in Resource Constrained Nodes for IoT Application
Authors: Sultan Alharby, Nick Harris, Alex Weddell, Jeff Reeve
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The concept of the Internet of Things (IoT) has received much attention over the last five years. It is predicted that the IoT will influence every aspect of our lifestyles in the near future. Wireless Sensor Networks are one of the key enablers of the operation of IoTs, allowing data to be collected from the surrounding environment. However, due to limited resources, nature of deployment and unattended operation, a WSN is vulnerable to various types of attack. Security is paramount for reliable and safe communication between IoT embedded devices, but it does, however, come at a cost to resources. Nodes are usually equipped with small batteries, which makes energy conservation crucial to IoT devices. Nevertheless, security cost in terms of energy consumption has not been studied sufficiently. Previous research has used a security specification of 802.15.4 for IoT applications, but the energy cost of each security level and the impact on quality of services (QoS) parameters remain unknown. This research focuses on the cost of security at the IoT media access control (MAC) layer. It begins by studying the energy consumption of IEEE 802.15.4 security levels, which is followed by an evaluation for the impact of security on data latency and throughput, and then presents the impact of transmission power on security overhead, and finally shows the effects of security on memory footprint. The results show that security overhead in terms of energy consumption with a payload of 24 bytes fluctuates between 31.5% at minimum level over non-secure packets and 60.4% at the top security level of 802.15.4 security specification. Also, it shows that security cost has less impact at longer packet lengths, and more with smaller packet size. In addition, the results depicts a significant impact on data latency and throughput. Overall, maximum authentication length decreases throughput by almost 53%, and encryption and authentication together by almost 62%.Keywords: energy consumption, IEEE 802.15.4, IoT security, security cost evaluation
Procedia PDF Downloads 168698 Preparation and Characterization of Cellulose Based Antimicrobial Food Packaging Materials
Authors: Memet Vezir Kahraman, Ferhat Sen
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This study aimed to develop polyelectrolyte structured antimicrobial food packaging materials that do not contain any antimicrobial agents. Cationic hydroxyethyl cellulose was synthesized and characterized by Fourier Transform Infrared, carbon and proton Nuclear Magnetic Resonance spectroscopy. Its nitrogen content was determined by the Kjeldahl method. Polyelectrolyte structured antimicrobial food packaging materials were prepared using hydroxyethyl cellulose, cationic hydroxyethyl cellulose, and sodium alginate. Antimicrobial activity of materials was defined by inhibition zone method (disc diffusion method). Thermal stability of samples was evaluated by thermal gravimetric analysis and differential scanning calorimetry. Surface morphology of samples was investigated by scanning electron microscope. The obtained results prove that produced food packaging materials have good thermal and antimicrobial properties, and they can be used as food packaging material in many industries.Keywords: antimicrobial food packaging, cationic hydroxyethyl cellulose, polyelectrolyte, sodium alginate
Procedia PDF Downloads 160697 The Tadpole-Shaped Polypeptides with Two Regulable (Alkyl Chain) Tails
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The biocompatible tadpole-shaped polypeptides with one cyclic polypeptides ring and two alkyl chain tails were synthesized by N-heterocyclic carbine (NHC)-mediated ring-opening polymerization (ROP) of α-amino acid N-carboxyanhydrides (NCAs). First, the NHC precursor, denoted as [NHC(H)][HCO₃], with two alkyl chains at the nitrogen was prepared by a simple anion metathesis of imidazole(in)ium chlorides with KHCO₃. Then NHC releasing from the [NHC(H)][HCO₃] directly initiated the ROP of NCA to produce the cyclic polypeptides. Finally, the tadpole-shaped polypeptides with two regulable tails were obtained. The target polypeptides were characterized by nuclear magnetic resonance spectrum (1H NMR), Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC) and matrix-assisted laser desorption ionization-time of flight mass spectra (MALDI-TOF MS). This pioneering approach simplifies the synthesis procedures of tadpole-shaped polypeptides compared to other methods, which usually requires specific intramolecular ring-closure reaction.Keywords: cyclic polypeptides, α-amino acid N-carboxyanhydrides, N-heterocyclic carbene, ring-opening polymerization, tadpole-shaped
Procedia PDF Downloads 206696 Agronomic Value of Wastewater and Sugar Beet Lime Sludge Compost on Radish Crop
Authors: S. Rida, O. Saadani Hassani, Q. R’zina, N. Saadaoui, K. Fares
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Wastewater treatment stations create large quantities of sludge, whose treatment is poorly underestimated in the draft installation. However, chemical analysis of sludge reveals their important concentration in fertilizer elements including nitrogen and phosphorus. The direct application of sludge can reveal contamination of the food chain because of their chemical and organic micropollutants load. Therefore, there is a need of treatment process before use. The treatment by composting of this sludge mixed with three different proportions of sugar beet lime sludge (0%, 20%,30%) and green waste permits to obtain a stable compost rich in mineral elements, having a pleasant smell and relatively hygienic. In addition, the use of compost in agriculture positively affects the plant-soil system. Thus, this study shows that the supply of compost improves the physical properties of the soil and its agronomic quality, which results in an increase in the biomass of cultivated radish plants and a larger crop.Keywords: agriculture, composting, soil, sugar beet lime, wastewater
Procedia PDF Downloads 323695 Production of a Sustainable Slow-Release Urea Fertilizer Using Starch and Poly-Vinyl Alcohol
Authors: A. M. H. Shokry, N. S. M. El-Tayeb
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The environmental impacts caused by fertilizers call for the adaptation of more sustainable technologies in order to increase agricultural production and reduce pollution due to high nutrient emissions. One particular technique has been to coat urea fertilizer granules with less-soluble chemicals that permit the gradual release of nutrients in a slow and controlled manner. The aim of this research is to develop a biodegradable slow-release fertilizer (SRF) with materials that come from sustainable sources; starch and polyvinyl alcohol (PVA). The slow-release behavior and water retention capacity of the coated granules were determined. In addition, the aqueous release and absorbency rates were also tested. Results confirmed that the release rate from coated granules was slower than through plain membranes; and that the water absorption capacity of the coated urea decreased as PVA content increased. The SRF was also tested and gave positive results that confirmed the integrity of the product.Keywords: biodegradability, nitrogen-use efficiency, poly-vinyl alcohol, slow-release fertilizer, sustainability
Procedia PDF Downloads 214694 Impact of Heavy Metal Toxicity on Metabolic Changes in the Diazotrophic Cyanobacterium Anabaena PCC 7120
Authors: Rishi Saxena
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Cyanobacteria is a photosynthetic prokaryote, and these obtain their energy through photosynthesis. In this paper, we studied the effect of iron on metabolic changes in the diazotrophic cyanobacterium Anabaena PCC 7120. Nowadays, metal contamination due to natural and anthropogenic sources is a global environment concern. Iron induced changes in growth, N2-fixation, CO2 fixation and photosynthetic activity were studied in a diazotrophic cyanobacterium Anabaena PCC 7120. Iron at 50 uM concentration supported the maximum growth, heterocyst frequency, CO2 fixation, photosystem I (PS I), photosystem II (PS II) and nitrogenase activities in the organism. Higher concentration of iron inhibited these processes. Chl a and PS II activities were more sensitive to iron than the protein and PS I activity. Here, it is also mentioned that heavy metal induced altered macromolecules metabolism and changes in the central dogma of life (DNA→ mRNA → Protein). And also recent advances have been made in understanding heavy metal-cyanobacteria interaction and their application for metal detoxification.Keywords: cyanobacterium anabaena 7120, nitrogen fixation, photosystem I (PS I), photosystem II (PS II)
Procedia PDF Downloads 137693 Graphen-Based Nanocomposites for Glucose and Ethanol Enzymatic Biosensor Fabrication
Authors: Tesfaye Alamirew, Delele Worku, Solomon W. Fanta, Nigus Gabbiye
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Recently graphen based nanocomposites are become an emerging research areas for fabrication of enzymatic biosensors due to their property of large surface area, conductivity and biocompatibility. This review summarizes recent research reports of graphen based nanocomposites for the fabrication of glucose and ethanol enzymatic biosensors. The newly fabricated enzyme free microwave treated nitrogen doped graphen (MN-d-GR) had provided highest sensitivity towards glucose and GCE/rGO/AuNPs/ADH composite had provided far highest sensitivity towards ethanol compared to other reported graphen based nanocomposites. The MWCNT/GO/GOx and GCE/ErGO/PTH/ADH nanocomposites had also enhanced wide linear range for glucose and ethanol detection respectively. Generally, graphen based nanocomposite enzymatic biosensors had fast direct electron transfer rate, highest sensitivity and wide linear detection ranges during glucose and ethanol sensing.Keywords: glucose, ethanol, enzymatic biosensor, graphen, nanocomposite
Procedia PDF Downloads 126692 Biohydrogen Production from Starch Residues
Authors: Francielo Vendruscolo
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This review summarizes the potential of starch agroindustrial residues as substrate for biohydrogen production. Types of potential starch agroindustrial residues, recent developments and bio-processing conditions for biohydrogen production will be discussed. Biohydrogen is a clean energy source with great potential to be an alternative fuel, because it releases energy explosively in heat engines or generates electricity in fuel cells producing water as only by-product. Anaerobic hydrogen fermentation or dark fermentation seems to be more favorable, since hydrogen is yielded at high rates and various organic waste enriched with carbohydrates as substrate result in low cost for hydrogen production. Abundant biomass from various industries could be source for biohydrogen production where combination of waste treatment and energy production would be an advantage. Carbohydrate-rich nitrogen-deficient solid wastes such as starch residues can be used for hydrogen production by using suitable bioprocess technologies. Alternatively, converting biomass into gaseous fuels, such as biohydrogen is possibly the most efficient way to use these agroindustrial residues.Keywords: biofuel, dark fermentation, starch residues, food waste
Procedia PDF Downloads 399691 Developing a Town Based Soil Database to Assess the Sensitive Zones in Nutrient Management
Authors: Sefa Aksu, Ünal Kızıl
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For this study, a town based soil database created in Gümüşçay District of Biga Town, Çanakkale, Turkey. Crop and livestock production are major activities in the district. Nutrient management is mainly based on commercial fertilizer application ignoring the livestock manure. Within the boundaries of district, 122 soil sampling points determined over the satellite image. Soil samples collected from the determined points with the help of handheld Global Positioning System. Labeled samples were sent to a commercial laboratory to determine 11 soil parameters including salinity, pH, lime, organic matter, nitrogen, phosphorus, potassium, iron, manganese, copper and zinc. Based on the test results soil maps for mentioned parameters were developed using remote sensing, GIS, and geostatistical analysis. In this study we developed a GIS database that will be used for soil nutrient management. Methods were explained and soil maps and their interpretations were summarized in the study.Keywords: geostatistics, GIS, nutrient management, soil mapping
Procedia PDF Downloads 375690 Optimization of Process Parameters for Peroxidase Production by Ensifer Species
Authors: Ayodeji O. Falade, Leonard V. Mabinya, Uchechukwu U. Nwodo, Anthony I. Okoh
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Given the high utility of peroxidase in several industrial processes, the search for novel microorganisms with enhanced peroxidase production capacity is of keen interest. This study investigated the process conditions for optimum peroxidase production by Ensifer sp, new ligninolytic proteobacteria with peroxidase production potential. Also, some agricultural residues were valorized for peroxidase production under solid state fermentation. Peroxidase production was optimum at an initial medium pH 7, incubation temperature of 30 °C and agitation speed of 100 rpm using alkali lignin fermentation medium supplemented with guaiacol as the most effective inducer and ammonium sulphate as the best inorganic nitrogen. Optimum peroxidase production by Ensifer sp. was attained at 48 h with specific productivity of 12.76 ± 1.09 U mg⁻¹. Interestingly, probable laccase production was observed with optimum specific productivity of 12.76 ± 0.45 U mg⁻¹ at 72 h. The highest peroxidase yield was observed with sawdust as solid substrate under solid state fermentation. In conclusion, Ensifer sp. possesses the capacity for enhanced peroxidase production that can be exploited for various biotechnological applications.Keywords: catalase-peroxidase, enzyme production, peroxidase, polymerase chain reaction, proteobacteria
Procedia PDF Downloads 308689 Determination of Water Pollution and Water Quality with Decision Trees
Authors: Çiğdem Bakır, Mecit Yüzkat
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With the increasing emphasis on water quality worldwide, the search for and expanding the market for new and intelligent monitoring systems has increased. The current method is the laboratory process, where samples are taken from bodies of water, and tests are carried out in laboratories. This method is time-consuming, a waste of manpower, and uneconomical. To solve this problem, we used machine learning methods to detect water pollution in our study. We created decision trees with the Orange3 software we used in our study and tried to determine all the factors that cause water pollution. An automatic prediction model based on water quality was developed by taking many model inputs such as water temperature, pH, transparency, conductivity, dissolved oxygen, and ammonia nitrogen with machine learning methods. The proposed approach consists of three stages: preprocessing of the data used, feature detection, and classification. We tried to determine the success of our study with different accuracy metrics and the results. We presented it comparatively. In addition, we achieved approximately 98% success with the decision tree.Keywords: decision tree, water quality, water pollution, machine learning
Procedia PDF Downloads 83688 A Computational Study of N–H…O Hydrogen Bonding to Investigate Cooperative Effects
Authors: Setareh Shekarsaraei, Marjan Moridi, Nasser L. Hadipour
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In this study, nuclear magnetic resonance spectroscopy and nuclear quadrupole resonance spectroscopy parameters of 14N (Nitrogen in imidazole ring) in N–H…O hydrogen bonding for Histidine hydrochloride monohydrate were calculated via density functional theory. We considered a five-molecule model system of Histidine hydrochloride monohydrate. Also, we examined the trends of environmental effect on hydrogen bonds as well as cooperativity. The functional used in this research is M06-2X which is a good functional and the obtained results have shown good agreement with experimental data. This functional was applied to calculate the NMR and NQR parameters. Some correlations among NBO parameters, NMR, and NQR parameters have been studied which have shown the existence of strong correlations among them. Furthermore, the geometry optimization has been performed using M062X/6-31++G(d,p) method. In addition, in order to study cooperativity and changes in structural parameters, along with increase in cluster size, natural bond orbitals have been employed.Keywords: hydrogen bonding, density functional theory (DFT), natural bond orbitals (NBO), cooperativity effect
Procedia PDF Downloads 456687 Total Lipid of Mutant Synechococcus sp. PCC 7002
Authors: Azlin S Azmi, Mus’ab Zainal, Sarina Sulaiman, Azura Amid, Zaki Zainudin
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Microalgae lipid is a promising feedstock for biodiesel production. The objective of this work was to study growth factors affecting marine mutant Synechococcus sp. (PCC 7002) for high lipid production. Four growth factors were investigated; nitrogen-phosporus-potassium (NPK) concentration, light intensity, temperature and NaNO3 concentration on mutant strain growth and lipid production were studied. Design Expert v8.0 was used to design the experimental and analyze the data. The experimental design selected was Min-Run Res IV which consists of 12 runs and the response surfaces measured were specific growth rate and lipid concentration. The extraction of lipid was conducted by chloroform/methanol solvents system. Based on the study, mutant Synechococcus sp. PCC 7002 gave the highest specific growth rate of 0.0014 h-1 at 0% NPK, 2500 lux, 40oC and 0% NaNO3. On the other hand, the highest lipid concentration was obtained at 0% NPK, 3500 lux, 30°C and 1% NaNO3.Keywords: Cyanobacteria, lipid, mutant, marine Synechococcus sp. (PCC 7002), specific growth rate
Procedia PDF Downloads 337686 Physicochemical Studies and Screening of Aflatoxins and Pesticide Residues in Some 'Honey Pastes' Marketed in Jeddah, Saudi Arabia
Authors: Rashad Al-Hindi
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The study aimed at investigating and screening of some contaminants in some honey-based products. Sixty-nine 'honey paste' samples marketed in Jeddah, Saudi Arabia, were subjected to physicochemical studies and screening of aflatoxins and pesticide residues. The physicochemical parameters studied were mainly: moisture content, total sugars, total ash, total nitrogen, fibres, total acidity as citric acid and pH. These parameters were investigated using standard methods of analysis. Mycotoxins (aflatoxins) and pesticide residues were by an enzyme-linked immunosorbent assay (ELISA) according to official methods. Results revealed that mean values of the examined criteria were: 15.44±0.36%; 74±4.30%; 0.40±0.062%; 0.22±0.05%; 6.93±1.30%; 2.53±0.161 mmol/kg; 4.10±0.158, respectively. Overall results proved that all tested honey pastes samples were free from mycotoxins (aflatoxins) and pesticide residues. Therefore, we conclude that 'honey pastes' marketed in Jeddah city, Saudi Arabia were safe for human consumption.Keywords: aflatoxins, honey mixtures, pesticide residues, physicochemical
Procedia PDF Downloads 177685 From Sampling to Sustainable Phosphate Recovery from Mine Waste Rock Piles
Authors: Hicham Amar, Mustapha El Ghorfi, Yassine Taha, Abdellatif Elghali, Rachid Hakkou, Mostafa Benzaazoua
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Phosphate mine waste rock (PMWR) generated during ore extraction is continuously increasing, resulting in a significant environmental footprint. The main objectives of this study consist of i) elaboration of the sampling strategy of PMWR piles, ii) a mineralogical and chemical characterization of PMWR piles, and iii) 3D block model creation to evaluate the potential valorization of the existing PMWR. Destructive drilling using reverse circulation from 13 drills was used to collect samples for chemical (X-ray fluorescence analysis) and mineralogical assays. The 3D block model was created based on the data set, including chemical data of the realized drills using Datamine RM software. The optical microscopy observations showed that the sandy phosphate from drills in the PMWR piles is characterized by the abundance of carbonate fluorapatite with the presence of calcite, dolomite, and quartz. The mean grade of composite samples was around 19.5±2.7% for P₂O₅. The mean grade of P₂O₅ exhibited an increasing tendency by depth profile from bottom to top of PMWR piles. 3D block model generated with chemical data confirmed the tendency of the mean grades’ variation and may allow a potential selective extraction according to %P₂O₅. The 3D block model of P₂O₅ grade is an efficient sampling approach that confirmed the variation of P₂O₅ grade. This integrated approach for PMWR management will be a helpful tool for decision-making to recover the residual phosphate, adopting the circular economy and sustainability in the phosphate mining industry.Keywords: 3D modelling, reverse circulation drilling, circular economy, phosphate mine waste rock, sampling
Procedia PDF Downloads 78684 Reaction Rate of Olive Stone during Combustion in a Bubbling Fluidized Bed
Authors: A. Soria-Verdugo, M. Rubio-Rubio, J. Arrieta, N. García-Hernando
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Combustion of biomass is a promising alternative to reduce the high pollutant emission levels associated to the combustion of fossil flues due to the net null emission of CO2 attributed to biomass. However, the biomass selected should also have low contents of nitrogen and sulfur to limit the NOx and SOx emissions derived from its combustion. In this sense, olive stone is an excellent fuel to power combustion reactors with reduced levels of pollutant emissions. In this work, the combustion of olive stone particles is analyzed experimentally in a thermogravimetric analyzer (TGA) and in a bubbling fluidized bed reactor (BFB). The bubbling fluidized bed reactor was installed over a scale, conforming a macro-TGA. In both equipment, the evolution of the mass of the samples was registered as the combustion process progressed. The results show a much faster combustion process in the bubbling fluidized bed reactor compared to the thermogravimetric analyzer measurements, due to the higher heat transfer coefficient and the abrasion of the fuel particles by the bed material in the BFB reactor.Keywords: olive stone, combustion, reaction rate, fluidized bed
Procedia PDF Downloads 201683 The Potential in the Use of Building Information Modelling and Life-Cycle Assessment for Retrofitting Buildings: A Study Based on Interviews with Experts in Both Fields
Authors: Alex Gonzalez Caceres, Jan Karlshøj, Tor Arvid Vik
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Life cycle of residential buildings are expected to be several decades, 40% of European residential buildings have inefficient energy conservation measure. The existing building represents 20-40% of the energy use and the CO₂ emission. Since net zero energy buildings are a short-term goal, (should be achieved by EU countries after 2020), is necessary to plan the next logical step, which is to prepare the existing outdated stack of building to retrofit them into an energy efficiency buildings. In order to accomplish this, two specialize and widespread tool can be used Building Information Modelling (BIM) and life-cycle assessment (LCA). BIM and LCA are tools used by a variety of disciplines; both are able to represent and analyze the constructions in different stages. The combination of these technologies could improve greatly the retrofitting techniques. The incorporation of the carbon footprint, introducing a single database source for different material analysis. To this is added the possibility of considering different analysis approaches such as costs and energy saving. Is expected with these measures, enrich the decision-making. The methodology is based on two main activities; the first task involved the collection of data this is accomplished by literature review and interview with experts in the retrofitting field and BIM technologies. The results of this task are presented as an evaluation checklist of BIM ability to manage data and improve decision-making in retrofitting projects. The last activity involves an evaluation using the results of the previous tasks, to check how far the IFC format can support the requirements by each specialist, and its uses by third party software. The result indicates that BIM/LCA have a great potential to improve the retrofitting process in existing buildings, but some modification must be done in order to meet the requirements of the specialists for both, retrofitting and LCA evaluators.Keywords: retrofitting, BIM, LCA, energy efficiency
Procedia PDF Downloads 220