Search results for: CCS (carbon capture and storage)
412 The Impact of Roof Thermal Performance on the Indoor Thermal Comfort in a Natural Ventilated Building Envelope in Hot Climatic Climates
Authors: J. Iwaro, A. Mwasha, K. Ramsubhag
Abstract:
Global warming has become a threat of our time. It poses challenges to the existence of beings on earth, the built environment, natural environment and has made a clear impact on the level of energy and water consumption. As such, increase in the ambient temperature increases indoor and outdoor temperature level of the buildings which brings about the use of more energy and mechanical air conditioning systems. In addition, in view of the increased modernization and economic growth in the developing countries, a significant amount of energy is being used, especially those with hot climatic conditions. Since modernization in developing countries is rising rapidly, more pressure is being placed on the buildings and energy resources to satisfy the indoor comfort requirements. This paper presents a sustainable passive roof solution as a means of reducing energy cooling loads for satisfying human comfort requirements in a hot climate. As such, the study based on the field study data discusses indoor thermal roof design strategies for a hot climate by investigating the impacts of roof thermal performance on indoor thermal comfort in naturally ventilated building envelope small scaled structures. In this respect, the traditional concrete flat roof, corrugated galvanised iron roof and pre-painted standing seam roof were used. The experiment made used of three identical small scale physical models constructed and sited on the roof of a building at the University of the West Indies. The results show that the utilization of insulation in traditional roofing systems will significantly reduce heat transfer between the internal and ambient environment, thus reducing the energy demand of the structure and the relative carbon footprint of a structure per unit area over its lifetime. Also, the application of flat slab concrete roofing system showed the best performance as opposed to the metal roof sheeting alternative systems. In addition, it has been shown experimentally through this study that a sustainable passive roof solution such as insulated flat concrete roof in hot dry climate has a better cooling strength that can provide building occupant with a better thermal comfort, conducive indoor conditions and energy efficiency.Keywords: building envelope, roof, energy consumption, thermal comfort
Procedia PDF Downloads 264411 Evolution of Microstructure through Phase Separation via Spinodal Decomposition in Spinel Ferrite Thin Films
Authors: Nipa Debnath, Harinarayan Das, Takahiko Kawaguchi, Naonori Sakamoto, Kazuo Shinozaki, Hisao Suzuki, Naoki Wakiya
Abstract:
Nowadays spinel ferrite magnetic thin films have drawn considerable attention due to their interesting magnetic and electrical properties with enhanced chemical and thermal stability. Spinel ferrite magnetic films can be implemented in magnetic data storage, sensors, and spin filters or microwave devices. It is well established that the structural, magnetic and transport properties of the magnetic thin films are dependent on microstructure. Spinodal decomposition (SD) is a phase separation process, whereby a material system is spontaneously separated into two phases with distinct compositions. The periodic microstructure is the characteristic feature of SD. Thus, SD can be exploited to control the microstructure at the nanoscale level. In bulk spinel ferrites having general formula, MₓFe₃₋ₓ O₄ (M= Co, Mn, Ni, Zn), phase separation via SD has been reported only for cobalt ferrite (CFO); however, long time post-annealing is required to occur the spinodal decomposition. We have found that SD occurs in CoF thin film without using any post-deposition annealing process if we apply magnetic field during thin film growth. Dynamic Aurora pulsed laser deposition (PLD) is a specially designed PLD system through which in-situ magnetic field (up to 2000 G) can be applied during thin film growth. The in-situ magnetic field suppresses the recombination of ions in the plume. In addition, the peak’s intensity of the ions in the spectra of the plume also increases when magnetic field is applied to the plume. As a result, ions with high kinetic energy strike into the substrate. Thus, ion-impingement occurred under magnetic field during thin film growth. The driving force of SD is the ion-impingement towards the substrates that is induced by in-situ magnetic field. In this study, we report about the occurrence of phase separation through SD and evolution of microstructure after phase separation in spinel ferrite thin films. The surface morphology of the phase separated films show checkerboard like domain structure. The cross-sectional microstructure of the phase separated films reveal columnar type phase separation. Herein, the decomposition wave propagates in lateral direction which has been confirmed from the lateral composition modulations in spinodally decomposed films. Large magnetic anisotropy has been found in spinodally decomposed nickel ferrite (NFO) thin films. This approach approves that magnetic field is also an important thermodynamic parameter to induce phase separation by the enhancement of up-hill diffusion in thin films. This thin film deposition technique could be a more efficient alternative for the fabrication of self-organized phase separated thin films and employed in controlling of the microstructure at nanoscale level.Keywords: Dynamic Aurora PLD, magnetic anisotropy, spinodal decomposition, spinel ferrite thin film
Procedia PDF Downloads 357410 Performance Assessment Of An Existing Multi-effect Desalination System Driven By Solar Energy
Authors: B. Shahzamanian, S. Varga, D. C. Alarcón-Padilla
Abstract:
Desalination is considered the primary alternative to increase water supply for domestic, agricultural and industrial use. Sustainable desalination is only possible in places where renewable energy resources are available. Solar energy is the most relevant type of renewable energy to driving desalination systems since most of the areas suffering from water scarcity are characterized by a high amount of available solar radiation during the year. Multi-Effect Desalination (MED) technology integrated with solar thermal concentrators is a suitable combination for heat-driven desalination. It can also be coupled with thermal vapour compressors or absorption heat pumps to boost overall system performance. The most interesting advantage of MED is the suitability to be used with a transient source of energy like solar. An experimental study was carried out to assess the performance of the most important life-size multi-effect desalination plant driven by solar energy located in the Plataforma Solar de Almería (PSA). The MED plant is used as a reference in many studies regarding multi-effect distillation. The system consists of a 14-effect MED plant coupled with a double-effect absorption heat pump. The required thermal energy to run the desalination system is supplied by means of hot water generated from 60 static flat-plate solar collectors with a total aperture area of 606 m2. In order to compensate for the solar energy variation, a thermal storage system with two interconnected tanks and an overall volume of 40 m3 is coupled to the MED unit. The multi-effect distillation unit is built in a forward feed configuration, and the last effect is connected to a double-effect LiBr-H2O absorption heat pump. The heat pump requires steam at 180 ºC (10 bar a) that is supplied by a small-aperture parabolic trough solar field with a total aperture area of 230 m2. When needed, a gas boiler is used as an auxiliary heat source for operating the heat pump and the MED plant when solar energy is not available. A set of experiments was carried out for evaluating the impact of the heating water temperature (Th), top brine temperature (TBT) and temperature difference between effects (ΔT) on the performance ratio of the MED plant. The considered range for variation of Th, TBT and ΔT was 60-70°C, 54-63°C and 1.1-1.6°C, respectively. The performance ratio (PR), defined as kg of distillate produced for every 2326 kJ of thermal energy supplied to the MED system, was almost independent of the applied variables with a variation of less than 5% for all the cases. The maximum recorded PR was 12.4. The results indicated that the system demonstrated robustness for the whole range of operating conditions considered. Author gratitude is expressed to the PSA for providing access to its installations, the support of its scientific and technical staff, and the financial support of the SFERA-III project (Grant Agreement No 823802). Special thanks to the access provider staff members who ensured the access support.Keywords: multi-effect distillation, performance ratio, robustness, solar energy
Procedia PDF Downloads 181409 Synthesis and Characterization of Highly Oriented Bismuth Oxyiodide Thin Films for the Photocatalytical Degradation of Pharmaceuticals Compounds in Water
Authors: Juan C. Duran-Alvarez, Daniel Mejia, Rodolfo Zanella
Abstract:
Heterogeneous photocatalysis is a promising method to achieve the complete degradation and mineralization of organic pollutants in water via their exhaustive oxidation. In order to take this advanced oxidation process towards sustainability, it is necessary to reduce the energy consumption, referred as the light sources and the post-treatment operations. For this, the synthesis of new nanostructures of low band gap semiconductors in the form of thin films is in continuous development. In this work, thin films of the low band gap semiconductor bismuth oxyiodide (BiOI) were synthesized via the Successive Ionic Layer Adsorption and Reaction (SILAR) method. For this, Bi(NO3)3 and KI solutions were prepared, and glass supports were immersed in each solution under strict rate and time immersion conditions. Synthesis was performed at room temperature and a washing step was set prior to each immersion. Thin films with an average thickness below 100 nm were obtained upon a cycle of 30 immersions, as determined by AFM and profilometry measurements. Cubic BiOI nanocrystals with average size of 17 nm and a high orientation to the 001 plane were observed by XRD. In order to optimize the synthesis method, several Bi/I ratios were tested, namely 1/1, 1/5, 1/10, 1/20 and 1/50. The highest crystallinity of the BiOI films was observed when the 1/5 ratio was used in the synthesis. Non-stoichiometric conditions also resulted in the highest uniformity of the thin layers. PVP was used as an additive to improve the adherence of the BiOI thin films to the support. The addition of 0.1 mg/mL of PVP during the washing step resulted in the highest adherence of the thin films. In photocatalysis tests, degradation rate of the antibiotic ciprofloxacin as high as 75% was achieved using visible light (380 to 700 nm) irradiation for 5 h in batch tests. Mineralization of the antibiotic was also observed, although in a lower extent; ~ 30% of the total organic carbon was removed upon 5 h of visible light irradiation. Some ciprofloxacin by-products were identified throughout the reaction; and some of these molecules displayed residual antibiotic activity. In conclusion, it is possible to obtain highly oriented BiOI thin films under ambient conditions via the SILAR method. Non-stoichiometric conditions using PVP additive are necessary to increase the crystallinity and adherence of the films, which are photocatalytically active to remove recalcitrant organic pollutants under visible light irradiation.Keywords: bismuth oxyhalides, photocatalysis, thin films, water treatment
Procedia PDF Downloads 112408 Transformative Measures in Chemical and Petrochemical Industry Through Agile Principles and Industry 4.0 Technologies
Authors: Bahman Ghorashi
Abstract:
The immense awareness of the global climate change has compelled traditional fossil fuel companies to develop strategies to reduce their carbon footprint and simultaneously consider the production of various sources of clean energy in order to mitigate the environmental impact of their operations. Similarly, supply chain issues, the scarcity of certain raw materials, energy costs as well as market needs, and changing consumer expectations have forced the traditional chemical industry to reexamine their time-honored modes of operation. This study examines how such transformative change might occur through the applications of agile principles as well as industry 4.0 technologies. Clearly, such a transformation is complex, costly, and requires a total commitment on the part of the top leadership and the entire management structure. Factors that need to be considered include organizational speed of change, a restructuring that would lend itself toward collaboration and the selling of solutions to customers’ problems, rather than just products, integrating ‘along’ as well as ‘across’ value chains, mastering change and uncertainty as well as a recognition of the importance of concept-to-cash time, i.e., the velocity of introducing new products to market, and the leveraging of people and information. At the same time, parallel to implementing such major shifts in the ethos, and the fabric of the organization, the change leaders should remain mindful of the companies’ DNA while incorporating the necessary DNA defying shifts. Furthermore, such strategic maneuvers should inevitably incorporate the managing of the upstream and downstream operations, harnessing future opportunities, preparing and training the workforce, implementing faster decision making and quick adaptation to change, managing accelerated response times, as well as forming autonomous and cross-functional teams. Moreover, the leaders should establish the balance between high-value solutions versus high-margin products, fully implement digitization of operations and, when appropriate, incorporate the latest relevant technologies, such as: AI, IIoT, ML, and immersive technologies. This study presents a summary of the agile principles and the relevant technologies and draws lessons from some of the best practices that are already implemented within the chemical industry in order to establish a roadmap to agility. Finally, the critical role of educational institutions in preparing the future workforce for Industry 4.0 is addressed.Keywords: agile principles, immersive technologies, industry 4.0, workforce preparation
Procedia PDF Downloads 100407 High Physical Properties of Biochar Issued from Cashew Nut Shell to Adsorb Mycotoxins (Aflatoxins and Ochratoxine A) and Its Effects on Toxigenic Molds
Authors: Abderahim Ahmadou, Alfredo Napoli, Noel Durand, Didier Montet
Abstract:
Biochar is a microporous and adsorbent solid carbon product obtained from the pyrolysis of various organic materials (biomass, agricultural waste). Biochar is distinguished from vegetable charcoal by its manufacture methods. Biochar is used as the amendment in soils to give them favorable characteristics under certain conditions, i.e., absorption of water and its release at low speed. Cashew nuts shell from Mali is usually discarded on land by local processors or burnt as a mean for waste management. The burning of this biomass poses serious socio-environmental problems including greenhouse gas emission and accumulation of tars and soot on houses closed to factories, leading to neighbor complaints. Some mycotoxins as aflatoxins are carcinogenic compounds resulting from the secondary metabolism of molds that develop on plants in the field and during their conservation. They are found at high level on some seeds and nuts in Africa. Ochratoxin A, member of mycotoxins, is produced by various species of Aspergillus and Penicillium. Human exposure to Ochratoxin A can occur through consumption of contaminated food products, particularly contaminated grain, as well as coffee, wine grapes. We showed that cashew shell biochars produced at 400, 600 and 800°C adsorbed aflatoxins (B1, B2, G1, G2) at 100% by filtration (rapid contact) as well as by stirring (long contact). The average percentage of adsorption of Ochratoxin A was 35% by filtration and 80% by stirring. The duration of the biochar-mycotoxin contact was a significant parameter. The effect of biochar was also tested on two strains of toxigenic molds: Aspergillus parasiticus (producers of Aflatoxins) and Aspergillus carbonarius (producers of Ochratoxins). The growth of the strain Aspergillus carbonarius was inhibited at up to 60% by the biochar at 600°C. An opposite effect to the inhibition was observed on Aspergillus parasiticus using the same biochar. In conclusion, we observed that biochar adsorbs mycotoxins: Aflatoxins and Ochratoxin A to different degrees; 100% adsorption of aflatoxins under all conditions (filtration and stirring) and adsorption of Ochratoxin A varied depending on the type of biochar and the experiment conditions (35% by filtration and 85% by stirring). The effects of biochar at 600 °C on the toxigenic molds: Aspergillus parasiticus and Aspergillus carbonarius, varied according to the experimental conditions and the strains. We observed an opposite effect on the growth with an inhibition of Aspergillus carbonarius up to 60% and a stimulated growth of Aspergillus parasiticus.Keywords: biochar, cashew nut shell, mycotoxins, toxicogenic molds
Procedia PDF Downloads 180406 Computational Modelling of pH-Responsive Nanovalves in Controlled-Release System
Authors: Tomilola J. Ajayi
Abstract:
A category of nanovalves system containing the α-cyclodextrin (α-CD) ring on a stalk tethered to the pores of mesoporous silica nanoparticles (MSN) is theoretically and computationally modelled. This functions to control opening and blocking of the MSN pores for efficient targeted drug release system. Modeling of the nanovalves is based on the interaction between α-CD and the stalk (p-anisidine) in relation to pH variation. Conformational analysis was carried out prior to the formation of the inclusion complex, to find the global minimum of both neutral and protonated stalk. B3LYP/6-311G**(d, p) basis set was employed to attain all theoretically possible conformers of the stalk. Six conformers were taken into considerations, and the dihedral angle (θ) around the reference atom (N17) of the p-anisidine stalk was scanned from 0° to 360° at 5° intervals. The most stable conformer was obtained at a dihedral angle of 85.3° and was fully optimized at B3LYP/6-311G**(d, p) level of theory. The most stable conformer obtained from conformational analysis was used as the starting structure to create the inclusion complexes. 9 complexes were formed by moving the neutral guest into the α-CD cavity along the Z-axis in 1 Å stepwise while keeping the distance between dummy atom and OMe oxygen atom on the stalk restricted. The dummy atom and the carbon atoms on α-CD structure were equally restricted for orientation A (see Scheme 1). The generated structures at each step were optimized with B3LYP/6-311G**(d, p) methods to determine their energy minima. Protonation of the nitrogen atom on the stalk occurs at acidic pH, leading to unsatisfactory host-guest interaction in the nanogate; hence there is dethreading. High required interaction energy and conformational change are theoretically established to drive the release of α-CD at a certain pH. The release was found to occur between pH 5-7 which agreed with reported experimental results. In this study, we applied the theoretical model for the prediction of the experimentally observed pH-responsive nanovalves which enables blocking, and opening of mesoporous silica nanoparticles pores for targeted drug release system. Our results show that two major factors are responsible for the cargo release at acidic pH. The higher interaction energy needed for the complex/nanovalve formation to exist after protonation as well as conformational change upon protonation are driving the release due to slight pH change from 5 to 7.Keywords: nanovalves, nanogate, mesoporous silica nanoparticles, cargo
Procedia PDF Downloads 117405 Reorientation of Sustainable Livestock Management: A Case Study Applied to Wastes Management in Faculty of Animal Husbandry, Padjadjaran University, Indonesia
Authors: Raka Rahmatulloh, Mohammad Ilham Nugraha, Muhammad Ifan Fathurrahman
Abstract:
The agricultural sector covers a wide area, one of them is livestock subsector that supply needs of the food source of animal protein. Animal protein is produced by the main livestock production such as meat, milk, eggs, etc. Besides the main production, livestock would produce metabolic residue, so called livestock wastes. Characteristics of livestock wastes can be either solid (feces), liquid (urine), and gas (methane) which turned out to be useful and has economical value when well-processed and well-controlled. Nowadays, this livestock wastes is considered as a source of pollutants, especially water pollution. If the source of pollutants used in an integrated way, it will have a positive impact on organic farming and a healthy environment. Management of livestock wastes can be integrated with the farming sector to the planting and caring that rely on fertilizers. Most Indonesian farmers still use chemical fertilizers, where the use of it in the long term will disturb the ecological balance of the environment. One of the main efforts is to use organic fertilizers instead of chemical fertilizer that conducted by the Faculty of Animal Husbandry, Padjadjaran University. The method is to use the solid waste of livestock and agricultural wastes into liquid organic fertilizer, feed additive, biogas and vermicompost through decomposition. The decomposition takes as long as 14 days including aeration and extraction process using water as a nutrients solvent media which contained in decomposes and disinfection media to release pathogenic microorganisms in decomposes. Liquid organic fertilizer has highly efficient for the farmers to have a ratio of carbon/nitrogen (C/N) 25/1 to 30/1 and neutral pH (6.5-7.5) which is good for plant growth. Feed additive may be given to improve the digestibility of feed so that substances can be easily absorbed by the body for production. Biogas contains methane (CH4), which has a high enough heat to produce electricity. Vermicompost is an overhaul of waste organic material that has excellent structure, porosity, aeration, drainage, and moisture holding capacity. Based on the case study above, an integrated livestock wastes management program strongly supports the Indonesian government in the achievement of sustainable livestock development.Keywords: integrated, livestock wastes, organic fertilizer, sustainable livestock development
Procedia PDF Downloads 429404 Establishing a Sustainable Construction Industry: Review of Barriers That Inhibit Adoption of Lean Construction in Lesotho
Authors: Tsepiso Mofolo, Luna Bergh
Abstract:
The Lesotho construction industry fails to embrace environmental practices, which has then lead to excessive consumption of resources, land degradation, air and water pollution, loss of habitats, and high energy usage. The industry is highly inefficient, and this undermines its capability to yield the optimum contribution to social, economic and environmental developments. Sustainable construction is, therefore, imperative to ensure the cultivation of benefits from all these intrinsic themes of sustainable development. The development of a sustainable construction industry requires a holistic approach that takes into consideration the interaction between Lean Construction principles, socio-economic and environmental policies, technological advancement and the principles of construction or project management. Sustainable construction is a cutting-edge phenomenon, forming a component of a subjectively defined concept called sustainable development. Sustainable development can be defined in terms of attitudes and judgments to assist in ensuring long-term environmental, social and economic growth in society. The key concept of sustainable construction is Lean Construction. Lean Construction emanates from the principles of the Toyota Production System (TPS), namely the application and adaptation of the fundamental concepts and principles that focus on waste reduction, the increase in value to the customer, and continuous improvement. The focus is on the reduction of socio-economic waste, and protestation of environmental degradation by reducing carbon dioxide emission footprint. Lean principles require a fundamental change in the behaviour and attitudes of the parties involved in order to overcome barriers to cooperation. Prevalent barriers to adoption of Lean Construction in Lesotho are mainly structural - such as unavailability of financing, corruption, operational inefficiency or wastage, lack of skills and training and inefficient construction legislation and political interferences. The consequential effects of these problems trigger down to quality, cost and time of the project - which then result in an escalation of operational costs due to the cost of rework or material wastage. Factor and correlation analysis of these barriers indicate that they are highly correlated, which then poses a detrimental potential to the country’s welfare, environment and construction safety. It is, therefore, critical for Lesotho’s construction industry to develop a robust governance through bureaucracy reforms and stringent law enforcement.Keywords: construction industry, sustainable development, sustainable construction industry, lean construction, barriers to sustainable construction
Procedia PDF Downloads 282403 Impact of Marangoni Stress and Mobile Surface Charge on Electrokinetics of Ionic Liquids Over Hydrophobic Surfaces
Authors: Somnath Bhattacharyya
Abstract:
The mobile adsorbed surface charge on hydrophobic surfaces can modify the velocity slip condition as well as create a Marangoni stress at the interface. The functionalized hydrophobic walls of micro/nanopores, e.g., graphene nanochannels, may possess physio-sorbed ions. The lateral mobility of the physisorbed absorbed ions creates a friction force as well as an electric force, leading to a modification in the velocity slip condition at the hydrophobic surface. In addition, the non-uniform distribution of these surface ions creates a surface tension gradient, leading to a Marangoni stress. The impact of the mobile surface charge on streaming potential and electrochemical energy conversion efficiency in a pressure-driven flow of ionized liquid through the nanopore is addressed. Also, enhanced electro-osmotic flow through the hydrophobic nanochannel is also analyzed. The mean-filed electrokinetic model is modified to take into account the short-range non-electrostatic steric interactions and the long-range Coulomb correlations. The steric interaction is modeled by considering the ions as charged hard spheres of finite radius suspended in the electrolyte medium. The electrochemical potential is modified by including the volume exclusion effect, which is modeled based on the BMCSL equation of state. The electrostatic correlation is accounted for in the ionic self-energy. The extremal of the self-energy leads to a fourth-order Poisson equation for the electric field. The ion transport is governed by the modified Nernst-Planck equation, which includes the ion steric interactions; born force arises due to the spatial variation of the dielectric permittivity and the dielectrophoretic force on the hydrated ions. This ion transport equation is coupled with the Navier-Stokes equation describing the flow of the ionized fluid and the 3fourth-order Poisson equation for the electric field. We numerically solve the coupled set of nonlinear governing equations along with the prescribed boundary conditions by adopting a control volume approach over a staggered grid arrangement. In the staggered grid arrangements, velocity components are stored on the midpoint of the cell faces to which they are normal, whereas the remaining scalar variables are stored at the center of each cell. The convection and electromigration terms are discretized at each interface of the control volumes using the total variation diminishing (TVD) approach to capture the strong convection resulting from the highly enhanced fluid flow due to the modified model. In order to link pressure to the continuity equation, we adopt a pressure correction-based iterative SIMPLE (Semi-Implicit Method for Pressure-Linked Equations) algorithm, in which the discretized continuity equation is converted to a Poisson equation involving pressure correction terms. Our results show that the physisorbed ions on a hydrophobic surface create an enhanced slip velocity when streaming potential, which enhances the convection current. However, the electroosmotic flow attenuates due to the mobile surface ions.Keywords: microfluidics, electroosmosis, streaming potential, electrostatic correlation, finite sized ions
Procedia PDF Downloads 65402 Effect of Inoculum Ratio on Dark Fermentative Hydrogen Production
Authors: Zeynep Yilmazer Hitit, Patrick C. Hallenbeck
Abstract:
Fuel reserve requirements due to depletion of fossil fuels have increased interest in biohydrogen since the 1990’s. In fermentative hydrogen production, pure, mixed, and co-cultures can be used to produce hydrogen. Several previous studies have evaluated hydrogen production by pure cultures of Clostridium butyricum or Enterobacter aerogenes. Evaluating hydrogen production by co-culture of these microorganisms is an interestıng approach since E. aerogenes is a facultative microorganism with resistance to oxygen in contrast to the strict anaerobe C. butyricum, and therefore has the ability to maintain anaerobic conditions. It was found that using co-cultures of facultative E. aerogenes (as a reducing agent and H2 producer) and the obligate anaerobe C. butyricum for producing hydrogen increases the yield of hydrogen by about 50% compared to C. butyricum by itself. Also, using different types of microorganisms for hydrogen production eliminates the need to use expensive reducing agents. C. butyricum strain pre-cultured anaerobically at 37 0C for 15h by inoculating 100 mL of GP medium (pH 6.8) consisting of 1% glucose, 2% polypeptone, 0.2% KH2PO4, 0.05% yeast extract, 0.05% MgSO4. 7H2O and E. aerogenes strain was pre-cultured aerobically at 30 0C, 150 rpm for 9 h by inoculating 100 mL of TGY medium (pH 6.8), consisting of 0.1% glucose, 0.5% tryptone, 0.1% K2HPO4, 0.5% yeast extract. All duplicate batch experiments were conducted in 100 mL bottles with different inoculum ratios of Clostridium butyricum and Enterobater aerogenes (C:E) using 5x diluted rich media (GP) consisting of 2 g/L glucose, 4g/L polypeptone, 0.4 g/L KH2PO4, 0.1 g/L yeast extract, 0.1 MgSO4.7H2O. The range of inoculum ratio of C. butyricum to E. aerogenes were 2:1,4:1,8:1, 1:2,1:4, 1:8, 1:0, 0:1. Using glucose as a carbon source aided in the observation of microbial behavior as well as making the effect of inoculum ratio more evident. Nearly all the glucose in the medium was used to produce hydrogen, except at a 1:0 ratio of inoculum (i.e. containing only C. butyricum). Low glucose consumption leads to a higher hydrogen yield due to cumulative hydrogen production and consumption of glucose, but not as much as C:E, 8:1. The lowest hydrogen yield was achieved in 1:8 inoculum ratio of C:E, 71.9 mL, 1.007±0.01 mol H2/mol glucose and the highest cumulative hydrogen, hydrogen yield and dry cell weight were achieved in 8:1 inoculum ratio of C:E, 117.4 mL, 2.035±0.082 mol H2/mol glucose, 0.4 g/L respectively. In this study effect of inoculum ratio on dark fermentative biohydrogen production using C. butyricum and E. aerogenes was investigated. The maximum hydrogen yield of 2.035mol H2/mol glucose was obtained using 2g/L glucose, an initial pH of 6 and an inoculum ratio of C. butyricum to E. aerogenes of 8:1. Results showed that inoculum ratio is an important parameter on hydrogen production due to competition between the two microorganisms in using substrate for growth and production of by-products. The results presented here could be of great significance for further waste management studies using co-culture hydrogen production.Keywords: biohydrogen, Clostridium butyricum, dark fermentation, Enterobacter aerogenes, inoculum ratio in biohydrogen production
Procedia PDF Downloads 229401 Prevalence of Rituximab Efficacy Over Immunosuppressants in Therapy of Systemic Sclerosis
Authors: Liudmila Garzanova, Lidia Ananyeva, Olga Koneva, Olga Ovsyannikova, Oxana Desinova, Mayya Starovoytova, Rushana Shayahmetova, Anna Khelkovskaya-Sergeeva
Abstract:
Abstract Objectives. Rituximab (RTX) shown a positive effect in the treatment of systemic sclerosis (SSc). But there is still not enough data on comparing the effectiveness of RTX with immunosuppressants (IS). The aim of our study was to compare changes of lung function and skin score in SSc between two groups of patients (pts) - on RXT therapy (prescribed after ineffectiveness of previous therapy with IS) and on therapy with IS only. Methods. This study included 103 pts received RTX as an addition to previous therapy (group 1) and 65 pts received therapy with IS and prednisolone (group 2). The mean follow-up period was 12.6±10.7months. In group 1 the mean age was 47±12.9 years, female – 88 pts (84%), the diffuse cutaneous subset of the disease had 55 pts (53%). The mean disease duration was 6.2±5.5 years. 82% pts had interstitial lung disease (ILD) and 92% were positive for ANA, 67% of them were positive for antitopoisomerase-1. All pts received prednisolone at a dose of 11.3±4.5 mg/day, IS at inclusion received 47% of them. The cumulative mean dose of RTX was 1.7±0.6 g. In group 2 the mean age was 50.8±13.8 years, female-53 pts (82%), the diffuse cutaneous subset of the disease had 44 pts (68%). The mean disease duration was 8.8±7.7 years. 81% pts had ILD and 88% were positive for ANA, 58% of them were positive for antitopoisomerase-1. All pts received prednisolone at a dose of 8.69±4.28 mg/day, IS received 57% of them. Cyclophosphamide (CP) received 45% of pts. The cumulative mean dose of CP was 10.2±15.1g. D-penicillamine received 30% of pts. Other pts was on mycophenolate mofetil or methotrexate therapy in single cases. The pts of the compared groups did not differ in the main demographic and clinical parameters. The results are presented as delta (Δ) - difference between the baseline parameter and follow up point. Results. In group 1 there was an improvement of all outcome parameters: increased of forced vital capacity, % predicted - ΔFVC=4% (p=0.0004); Diffusing capacity for carbon monoxide, % predicted remained stable (ΔDLCO=0.1%); improvement of the Rodnan skin score-ΔmRss=3.4 (p=0.001); decrease of Activity index (EScSG-AI) - ΔActivity index=1.7 (p=0.001). In group 2 the changes was insignificant: ΔFVC=-2.3%, ΔmRss=0.87, ΔActivity index=0.3. But there was a significant decrease of DLCO: ΔDLCO=-5.1% (p=0.001). Conclusion. The results of our study confirm the data on the positive effect of RTX in complex therapy in pts with SSc (decrease of skin induration, increase of FVC, stabilization of DLCO). Meantime, pts on IS and prednisolone therapy shown the worsening of lung function and insignificant changes of other clinical parameters. RTX could be considered as a more effective option in complex treatment of SSc in comparison with IS therapyKeywords: immunosuppressants, interstitial lung disease, systemic sclerosis, rituximab
Procedia PDF Downloads 75400 Distributed Listening in Intensive Care: Nurses’ Collective Alarm Responses Unravelled through Auditory Spatiotemporal Trajectories
Authors: Michael Sonne Kristensen, Frank Loesche, James Foster, Elif Ozcan, Judy Edworthy
Abstract:
Auditory alarms play an integral role in intensive care nurses’ daily work. Most medical devices in the intensive care unit (ICU) are designed to produce alarm sounds in order to make nurses aware of immediate or prospective safety risks. The utilisation of sound as a carrier of crucial patient information is highly dependent on nurses’ presence - both physically and mentally. For ICU nurses, especially the ones who work with stationary alarm devices at the patient bed space, it is a challenge to display ‘appropriate’ alarm responses at all times as they have to navigate with great flexibility in a complex work environment. While being primarily responsible for a small number of allocated patients they are often required to engage with other nurses’ patients, relatives, and colleagues at different locations inside and outside the unit. This work explores the social strategies used by a team of nurses to comprehend and react to the information conveyed by the alarms in the ICU. Two main research questions guide the study: To what extent do alarms from a patient bed space reach the relevant responsible nurse by direct auditory exposure? By which means do responsible nurses get informed about their patients’ alarms when not directly exposed to the alarms? A comprehensive video-ethnographic field study was carried out to capture and evaluate alarm-related events in an ICU. The study involved close collaboration with four nurses who wore eye-level cameras and ear-level binaural audio recorders during several work shifts. At all time the entire unit was monitored by multiple video and audio recorders. From a data set of hundreds of hours of recorded material information about the nurses’ location, social interaction, and alarm exposure at any point in time was coded in a multi-channel replay-interface. The data shows that responsible nurses’ direct exposure and awareness of the alarms of their allocated patients vary significantly depending on work load, social relationships, and the location of the patient’s bed space. Distributed listening is deliberately employed by the nursing team as a social strategy to respond adequately to alarms, but the patterns of information flow prompted by alarm-related events are not uniform. Auditory Spatiotemporal Trajectory (AST) is proposed as a methodological label to designate the integration of temporal, spatial and auditory load information. As a mixed-method metrics it provides tangible evidence of how nurses’ individual alarm-related experiences differ from one another and from stationary points in the ICU. Furthermore, it is used to demonstrate how alarm-related information reaches the individual nurse through principles of social and distributed cognition, and how that information relates to the actual alarm event. Thereby it bridges a long-standing gap in the literature on medical alarm utilisation between, on the one hand, initiatives to measure objective data of the medical sound environment without consideration for any human experience, and, on the other hand, initiatives to study subjective experiences of the medical sound environment without detailed evidence of the objective characteristics of the environment.Keywords: auditory spatiotemporal trajectory, medical alarms, social cognition, video-ethography
Procedia PDF Downloads 187399 A Comparison of Videography Tools and Techniques in African and International Contexts
Authors: Enoch Ocran
Abstract:
Film Pertinence maintains consistency in storytelling by sustaining the natural flow of action while evoking a particular feeling or emotion from the viewers with selected motion pictures. This study presents a thorough investigation of "Film Pertinence" in videography that examines its influence in Africa and around the world. This research delves into the dynamic realm of visual storytelling through film, with a specific focus on the concept of Film Pertinence (FP). The study’s primary objectives are to conduct a comparative analysis of videography tools and techniques employed in both African and international contexts, examining how they contribute to the achievement of organizational goals and the enhancement of cultural awareness. The research methodology includes a comprehensive literature review, interviews with videographers from diverse backgrounds in Africa and the international arena, and the examination of pertinent case studies. The investigation aims to elucidate the multifaceted nature of videographic practices, with particular attention to equipment choices, visual storytelling techniques, cultural sensitivity, and adaptability. This study explores the impact of cultural differences on videography choices, aiming to promote understanding between African and foreign filmmakers and create more culturally sensitive films. It also explores the role of technology in advancing videography practices, resource allocation, and the influence of globalization on local filmmaking practices. The research also contributes to film studies by analyzing videography's impact on storytelling, guiding filmmakers to create more compelling narratives. The findings can inform film education, tailoring curricula to regional needs and opportunities. The study also encourages cross-cultural collaboration in the film industry by highlighting convergence and divergence in videography practices. At its core, this study seeks to explore the implications of film pertinence as a framework for videographic practice. It scrutinizes how cultural expression, education, and storytelling transcend geographical boundaries on a global scale. By analyzing the interplay between tools, techniques, and context, the research illuminates the ways in which videographers in Africa and worldwide apply film Pertinence principles to achieve cross-cultural communication and effectively capture the objectives of their clients. One notable focus of this paper is on the techniques employed by videographers in West Africa to emphasize storytelling and participant engagement, showcasing the relevance of FP in highlighting cultural awareness in visual storytelling. Additionally, the study highlights the prevalence of film pertinence in African agricultural documentaries produced for esteemed organizations such as the Roundtable on Sustainable Palm Oil (RSPO), Proforest, World Food Program, Fidelity Bank Ghana, Instituto BVRio, Aflatoun International, and the Solidaridad Network. These documentaries serve to promote prosperity, resilience, human rights, sustainable farming practices, community respect, and environmental preservation, underlining the vital role of film in conveying these critical messages. In summary, this research offers valuable insights into the evolving landscape of videography in different contexts, emphasizing the significance of film pertinence as a unifying principle in the pursuit of effective visual storytelling and cross-cultural communication.Keywords: film pertinence, Africa, cultural awareness, videography tools
Procedia PDF Downloads 59398 Research on Tight Sandstone Oil Accumulation Process of the Third Member of Shahejie Formation in Dongpu Depression, China
Authors: Hui Li, Xiongqi Pang
Abstract:
In recent years, tight oil has become a hot spot for unconventional oil and gas exploration and development in the world. Dongpu Depression is a typical hydrocarbon-rich basin in the southwest of Bohai Bay Basin, in which tight sandstone oil and gas have been discovered in deep reservoirs, most of which are buried more than 3500m. The distribution and development characteristics of deep tight sandstone reservoirs need to be studied. The main source rocks in study area are dark mudstone and shale of the middle and lower third sub-member of Shahejie Formation. Total Organic Carbon (TOC) content of source rock is between 0.08-11.54%, generally higher than 0.6% and the value of S1+S2 is between 0.04–72.93 mg/g, generally higher than 2 mg/g. It can be evaluated as middle to fine level overall. The kerogen type of organic matter is predominantly typeⅡ1 andⅡ2. Vitrinite reflectance (Ro) is mostly greater than 0.6% indicating that the source rock entered the hydrocarbon generation threshold. The physical property of reservoir was poor, the most reservoir has a porosity lower than 12% and a permeability of less than 1×10⁻³μm. The rocks in this area showed great heterogeneity, some areas developed desserts with high porosity and permeability. According to SEM, thin section image, inclusion test and so on, the reservoir was affected by compaction and cementation during early diagenesis stage (44-31Ma). The diagenesis caused the tight reservoir in Huzhuangji, Pucheng, Weicheng Area while the porosity in Machang, Qiaokou, Wenliu Area was still over 12%. In the process of middle diagenesis phase stage A (31-17Ma), the reservoir porosity in Machang, Pucheng, Huzhuangji Area increased due to dissolution; after that the oil generation window of source rock was achieved for the first phase hydrocarbon charging (31-23Ma), formed the conventional oil deposition in Machang, Qiaokou, Wenliu, Huzhuangji Area and unconventional tight reservoir in Pucheng, Weicheng Area. Then came to stage B of middle diagenesis phase (17-7Ma), in this stage, the porosity of reservoir continued to decrease after the dissolution and led to a situation that the reservoirs were generally compacted. And since then, the second hydrocarbon filling has been processing since 7Ma. Most of the pools charged and formed in this procedure are tight sandstone oil reservoir. In conclusion, tight sandstone oil was formed in two patterns in Dongpu Depression, which could be concluded as ‘density fist then accumulation’ pattern and ‘accumulation fist next density’ pattern.Keywords: accumulation process, diagenesis, dongpu depression, tight sandstone oil
Procedia PDF Downloads 111397 Optimizing Solids Control and Cuttings Dewatering for Water-Powered Percussive Drilling in Mineral Exploration
Authors: S. J. Addinell, A. F. Grabsch, P. D. Fawell, B. Evans
Abstract:
The Deep Exploration Technologies Cooperative Research Centre (DET CRC) is researching and developing a new coiled tubing based greenfields mineral exploration drilling system utilising down-hole water-powered percussive drill tooling. This new drilling system is aimed at significantly reducing the costs associated with identifying mineral resource deposits beneath deep, barren cover. This system has shown superior rates of penetration in water-rich, hard rock formations at depths exceeding 500 metres. With fluid flow rates of up to 120 litres per minute at 200 bar operating pressure to energise the bottom hole tooling, excessive quantities of high quality drilling fluid (water) would be required for a prolonged drilling campaign. As a result, drilling fluid recovery and recycling has been identified as a necessary option to minimise costs and logistical effort. While the majority of the cuttings report as coarse particles, a significant fines fraction will typically also be present. To maximise tool life longevity, the percussive bottom hole assembly requires high quality fluid with minimal solids loading and any recycled fluid needs to have a solids cut point below 40 microns and a concentration less than 400 ppm before it can be used to reenergise the system. This paper presents experimental results obtained from the research program during laboratory and field testing of the prototype drilling system. A study of the morphological aspects of the cuttings generated during the percussive drilling process shows a strong power law relationship for particle size distributions. This data is critical in optimising solids control strategies and cuttings dewatering techniques. Optimisation of deployable solids control equipment is discussed and how the required centrate clarity was achieved in the presence of pyrite-rich metasediment cuttings. Key results were the successful pre-aggregation of fines through the selection and use of high molecular weight anionic polyacrylamide flocculants and the techniques developed for optimal dosing prior to scroll decanter centrifugation, thus keeping sub 40 micron solids loading within prescribed limits. Experiments on maximising fines capture in the presence of thixotropic drilling fluid additives (e.g. Xanthan gum and other biopolymers) are also discussed. As no core is produced during the drilling process, it is intended that the particle laden returned drilling fluid is used for top-of-hole geochemical and mineralogical assessment. A discussion is therefore presented on the biasing and latency of cuttings representivity by dewatering techniques, as well as the resulting detrimental effects on depth fidelity and accuracy. Data pertaining to the sample biasing with respect to geochemical signatures due to particle size distributions is presented and shows that, depending on the solids control and dewatering techniques used, it can have unwanted influence on top-of-hole analysis. Strategies are proposed to overcome these effects, improving sample quality. Successful solids control and cuttings dewatering for water-powered percussive drilling is presented, contributing towards the successful advancement of coiled tubing based greenfields mineral exploration.Keywords: cuttings, dewatering, flocculation, percussive drilling, solids control
Procedia PDF Downloads 243396 Missed Opportunities for Immunization of under Five Children in Calabar South County Cros River State, Nigeria, the Way Forward
Authors: Celestine Odigwe, Epoke Lincoln, Rhoda-Dara Ephraim
Abstract:
Background; Immunization against the childhood killer diseases is the cardinal strategy for the prevention of these diseases all over the world in under five children, these diseases include; Tuberculosis, Measles, Polio, Tetanus, Diphthria, Pertusis, Yellow Fever, Hepatitis B, Haemophilus Influenza type B. 6.9 million children die before their fifth birthday , 80% of the worlds death in children under 5 years occur in 25 countries most in Africa and Asia and 2 million children can be saved each year with routine immunization Therefore failure to achieve total immunization coverage puts several children at risk. Aim; The aim of the study was to ascertain the prevalence, Investigate the various reasons and causes why several under five children in a suburb of calabar municipal county fail to get the required immunizations as at and when due and possibly the consequences, so that efforts can be re-directed towards the solution of the problems so identified. Methods; the study was a community based cross sectional study. The respondents were the mothers/guardians of the sampled children who were all aged 0-59 months. To be eligible for recruitment into the study, the parent or guardian was required to give an informed consent, reside within the Calabar South County with his/her children aged 0-59 months. We calculated our sample size using the Leslie-Kish formula and we used a two-staged sampling method, first to ballot for the wards to be involved and then to select four of the most populated ones in the wards chosen. Data collection was by interviewer administered structured questionnaire (Appendix I), Data collected was entered and analyzed using Statistical Package for the Social Sciences (SPSS) Version 20. Percentages were calculated and represented using charts and tables Results; The number of children sampled was 159. We found that 150 were fully immunized and 9 were not, the prevalence of missed opportunity was 32% from the study. The reasons for missed opportunities were varied, ranging from false contraindications, logistical problems resulting in very poor access roads to health facilities and poor organization of health centers together with negative health worker attitudes. Some of the consequences of these missed opportunities were increased susceptibility to vaccine preventable diseases, resurgence of the above diseases and increased morbidity and mortality of children aged less than 5 years. Conclusion; We found that ignorance on the part of both parents/guardians and health care staff together with infrastructural inadequacies in the county such as- roads, poor electric power supply for storage of vaccines were hugely responsible for most missed opportunities for immunization. The details of these and suggestions for improvement and the way forward are discussed.Keywords: missed opportunity, immunization, under five, Calabar south
Procedia PDF Downloads 320395 Comparative Study of Urban Structure between an Island-Type and a General-Type City
Authors: Tomoya Oshiro, Hiroko Ono
Abstract:
Japan's aging population is increasing due to the decrease in birthrate. It causes various problems like the decrease in the gross domestic product of the country. The reason is why the local government of Japan has been on the way to a sustainable city recently. Then it is essential to get control of an urban structure to make the compact city successful. There are many kinds of paper about the compact city; however, the paper about a compact city of the island-type city is less. The purpose of this study is to clarify difference of urban structure between an island-type and a general city type. The method which has conducted in this research has two steps. First of all, by using evaluation indexes in the handbook, we evaluated the urban structures among each same -population-class cities from 50,000 to 100,000 people. Next, to clear the difference about the urban structure and feature between island-type and general-type cities compare the radar chart which is composed with each evaluation indexes of urban structure. Moreover, in order to clarify the relationship between evaluation indexes and the place of residence by using GIS software to show up population density on the map. As a result of this research, the management of local government and the local economy in evaluation indexes are indicated to be negative point in comparison of island-type cities with general cities. However, evaluation indexes of safety/security and low-carbon/energy are proved to be positive point. The research to find the difference features of the island-type of urban structure proves that the management of local government or the local economy is negative point in these island-type cities. In addition, the public transportation coverage in Miyako Island, Sado Island, and Amakusa Island show low value compare with other islands and average value. Relationship between evaluation indexes of an urban structure and the place of residence prove that the place of residence is related to public transportation coverage. If the place of residence is spread out, the public transportation coverage will be decreased. The results of this research reveal that the finances in island-type cities are negative point compare to general cities. This problem is caused by declining population. In addition, the place of residence is related to the public transportation coverage. Even though, it needs a much money to increase the public transportation coverage. It is possibly to cause other problems furthermore the aspect of finance is influenced by that as well. The conclusion in this research suggests that it is important for creating the compact city in island-type cities that we first need to address solving the problems about the management of local government and the local economy.Keywords: sustainable city, comparative analysis, geographic information system, urban structure
Procedia PDF Downloads 145394 The Characterization and Optimization of Bio-Graphene Derived From Oil Palm Shell Through Slow Pyrolysis Environment and Its Electrical Conductivity and Capacitance Performance as Electrodes Materials in Fast Charging Supercapacitor Application
Authors: Nurhafizah Md. Disa, Nurhayati Binti Abdullah, Muhammad Rabie Bin Omar
Abstract:
This research intends to identify the existing knowledge gap because of the lack of substantial studies to fabricate and characterize bio-graphene created from Oil Palm Shell (OPS) through the means of pre-treatment and slow pyrolysis. By fabricating bio-graphene through OPS, a novel material can be found to procure and used for graphene-based research. The characterization of produced bio-graphene is intended to possess a unique hexagonal graphene pattern and graphene properties in comparison to other previously fabricated graphene. The OPS will be fabricated by pre-treatment of zinc chloride (ZnCl₂) and iron (III) chloride (FeCl3), which then induced the bio-graphene thermally by slow pyrolysis. The pyrolizer's final temperature and resident time will be set at 550 °C, 5/min, and 1 hour respectively. Finally, the charred product will be washed with hydrochloric acid (HCL) to remove metal residue. The obtained bio-graphene will undergo different analyses to investigate the physicochemical properties of the two-dimensional layer of carbon atoms with sp2 hybridization hexagonal lattice structure. The analysis that will be taking place is Raman Spectroscopy (RAMAN), UV-visible spectroscopy (UV-VIS), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). In retrospect, RAMAN is used to analyze three key peaks found in graphene, namely D, G, and 2D peaks, which will evaluate the quality of the bio-graphene structure and the number of layers generated. To compare and strengthen graphene layer resolves, UV-VIS may be used to establish similar results of graphene layer from last layer analysis and also characterize the types of graphene procured. A clear physical image of graphene can be obtained by analyzation of TEM in order to study structural quality and layers condition and SEM in order to study the surface quality and repeating porosity pattern. Lastly, establishing the crystallinity of the produced bio-graphene, simultaneously as an oxygen contamination factor and thus pristineness of the graphene can be done by XRD. In the conclusion of this paper, this study is able to obtain bio-graphene through OPS as a novel material in pre-treatment by chloride ZnCl₂ and FeCl3 and slow pyrolization to provide a characterization analysis related to bio-graphene that will be beneficial for future graphene-related applications. The characterization should yield similar findings to previous papers as to confirm graphene quality.Keywords: oil palm shell, bio-graphene, pre-treatment, slow pyrolysis
Procedia PDF Downloads 78393 Coulomb-Explosion Driven Proton Focusing in an Arched CH Target
Authors: W. Q. Wang, Y. Yin, D. B. Zou, T. P. Yu, J. M. Ouyang, F. Q. Shao
Abstract:
High-energy-density state, i.e., matter and radiation at energy densities in excess of 10^11 J/m^3, is related to material, nuclear physics, astrophysics, and geophysics. Laser-driven particle beams are better suited to heat the matter as a trigger due to their unique properties of ultrashort duration and low emittance. Compared to X-ray and electron sources, it is easier to generate uniformly heated large-volume material for the proton and ion beams because of highly localized energy deposition. With the construction of state-of-art high power laser facilities, creating of extremely conditions of high-temperature and high-density in laboratories becomes possible. It has been demonstrated that on a picosecond time scale the solid density material can be isochorically heated to over 20 eV by the ultrafast proton beam generated from spherically shaped targets. For the above-mentioned technique, the proton energy density plays a crucial role in the formation of warm dense matter states. Recently, several methods have devoted to realize the focusing of the accelerated protons, involving externally exerted static-fields or specially designed targets interacting with a single or multi-pile laser pulses. In previous works, two co-propagating or opposite direction laser pulses are employed to strike a submicron plasma-shell. However, ultra-high pulse intensities, accurately temporal synchronization and undesirable transverse instabilities for a long time are still intractable for currently experimental implementations. A mechanism of the focusing of laser-driven proton beams from two-ion-species arched targets is investigated by multi-dimensional particle-in-cell simulations. When an intense linearly-polarized laser pulse impinges on the thin arched target, all electrons are completely evacuated, leading to a Coulomb-explosive electric-field mostly originated from the heavier carbon ions. The lighter protons in the moving reference frame by the ionic sound speed will be accelerated and effectively focused because of this radially isotropic field. At a 2.42×10^21 W/cm^2 laser intensity, a ballistic proton bunch with its energy-density as high as 2.15×10^17 J/m^3 is produced, and the highest proton energy and the focusing position agree well with that from the theory.Keywords: Coulomb explosion, focusing, high-energy-density, ion acceleration
Procedia PDF Downloads 330392 Acoustic Energy Harvesting Using Polyvinylidene Fluoride (PVDF) and PVDF-ZnO Piezoelectric Polymer
Authors: S. M. Giripunje, Mohit Kumar
Abstract:
Acoustic energy that exists in our everyday life and environment have been overlooked as a green energy that can be extracted, generated, and consumed without any significant negative impact to the environment. The harvested energy can be used to enable new technology like wireless sensor networks. Technological developments in the realization of truly autonomous MEMS devices and energy storage systems have made acoustic energy harvesting (AEH) an increasingly viable technology. AEH is the process of converting high and continuous acoustic waves from the environment into electrical energy by using an acoustic transducer or resonator. AEH is not popular as other types of energy harvesting methods since sound waves have lower energy density and such energy can only be harvested in very noisy environment. However, the energy requirements for certain applications are also correspondingly low and also there is a necessity to observe the noise to reduce noise pollution. So the ability to reclaim acoustic energy and store it in a usable electrical form enables a novel means of supplying power to relatively low power devices. A quarter-wavelength straight-tube acoustic resonator as an acoustic energy harvester is introduced with polyvinylidene fluoride (PVDF) and PVDF doped with ZnO nanoparticles, piezoelectric cantilever beams placed inside the resonator. When the resonator is excited by an incident acoustic wave at its first acoustic eigen frequency, an amplified acoustic resonant standing wave is developed inside the resonator. The acoustic pressure gradient of the amplified standing wave then drives the vibration motion of the PVDF piezoelectric beams, generating electricity due to the direct piezoelectric effect. In order to maximize the amount of the harvested energy, each PVDF and PVDF-ZnO piezoelectric beam has been designed to have the same structural eigen frequency as the acoustic eigen frequency of the resonator. With a single PVDF beam placed inside the resonator, the harvested voltage and power become the maximum near the resonator tube open inlet where the largest acoustic pressure gradient vibrates the PVDF beam. As the beam is moved to the resonator tube closed end, the voltage and power gradually decrease due to the decreased acoustic pressure gradient. Multiple piezoelectric beams PVDF and PVDF-ZnO have been placed inside the resonator with two different configurations: the aligned and zigzag configurations. With the zigzag configuration which has the more open path for acoustic air particle motions, the significant increases in the harvested voltage and power have been observed. Due to the interruption of acoustic air particle motion caused by the beams, it is found that placing PVDF beams near the closed tube end is not beneficial. The total output voltage of the piezoelectric beams increases linearly as the incident sound pressure increases. This study therefore reveals that the proposed technique used to harvest sound wave energy has great potential of converting free energy into useful energy.Keywords: acoustic energy, acoustic resonator, energy harvester, eigenfrequency, polyvinylidene fluoride (PVDF)
Procedia PDF Downloads 376391 Study of the Impact of Quality Management System on Chinese Baby Dairy Product Industries
Authors: Qingxin Chen, Liben Jiang, Andrew Smith, Karim Hadjri
Abstract:
Since 2007, the Chinese food industry has undergone serious food contamination in the baby dairy industry, especially milk powder contamination. One of the milk powder products was found to contain melamine and a significant number (294,000) of babies were affected by kidney stones. Due to growing concerns among consumers about food safety and protection, and high pressure from central government, companies must take radical action to ensure food quality protection through the use of an appropriate quality management system. Previously, though researchers have investigated the health and safety aspects of food industries and products, quality issues concerning food products in China have been largely over-looked. Issues associated with baby dairy products and their quality issues have not been discussed in depth. This paper investigates the impact of quality management systems on the Chinese baby dairy product industry. A literature review was carried out to analyse the use of quality management systems within the Chinese milk power market. Moreover, quality concepts, relevant standards, laws, regulations and special issues (such as Melamine, Flavacin M1 contamination) have been analysed in detail. A qualitative research approach is employed, whereby preliminary analysis was conducted by interview, and data analysis based on interview responses from four selected Chinese baby dairy product companies was carried out. Through the analysis of literature review and data findings, it has been revealed that for quality management system that has been designed by many practitioners, many theories, models, conceptualisation, and systems are present. These standards and procedures should be followed in order to provide quality products to consumers, but the implementation is lacking in the Chinese baby dairy industry. Quality management systems have been applied by the selected companies but the implementation still needs improvement. For instance, the companies have to take measures to improve their processes and procedures with relevant standards. The government need to make more interventions and take a greater supervisory role in the production process. In general, this research presents implications for the regulatory bodies, Chinese Government and dairy food companies. There are food safety laws prevalent in China but they have not been widely practiced by companies. Regulatory bodies must take a greater role in ensuring compliance with laws and regulations. The Chinese government must also play a special role in urging companies to implement relevant quality control processes. The baby dairy companies not only have to accept the interventions from the regulatory bodies and government, they also need to ensure that production, storage, distribution and other processes will follow the relevant rules and standards.Keywords: baby dairy product, food quality, milk powder contamination, quality management system
Procedia PDF Downloads 466390 Evaluation of Batch Splitting in the Context of Load Scattering
Authors: S. Wesebaum, S. Willeke
Abstract:
Production companies are faced with an increasingly turbulent business environment, which demands very high production volumes- and delivery date flexibility. If a decoupling by storage stages is not possible (e.g. at a contract manufacturing company) or undesirable from a logistical point of view, load scattering effects the production processes. ‘Load’ characterizes timing and quantity incidence of production orders (e.g. in work content hours) to workstations in the production, which results in specific capacity requirements. Insufficient coordination between load (demand capacity) and capacity supply results in heavy load scattering, which can be described by deviations and uncertainties in the input behavior of a capacity unit. In order to respond to fluctuating loads, companies try to implement consistent and realizable input behavior using the capacity supply available. For example, a uniform and high level of equipment capacity utilization keeps production costs down. In contrast, strong load scattering at workstations leads to performance loss or disproportionately fluctuating WIP, whereby the logistics objectives are affected negatively. Options for reducing load scattering are e.g. shifting the start and end dates of orders, batch splitting and outsourcing of operations or shifting to other workstations. This leads to an adjustment of load to capacity supply, and thus to a reduction of load scattering. If the adaptation of load to capacity cannot be satisfied completely, possibly flexible capacity must be used to ensure that the performance of a workstation does not decrease for a given load. Where the use of flexible capacities normally raises costs, an adjustment of load to capacity supply reduces load scattering and, in consequence, costs. In the literature you mostly find qualitative statements for describing load scattering. Quantitative evaluation methods that describe load mathematically are rare. In this article the authors discuss existing approaches for calculating load scattering and their various disadvantages such as lack of opportunity for normalization. These approaches are the basis for the development of our mathematical quantification approach for describing load scattering that compensates the disadvantages of the current quantification approaches. After presenting our mathematical quantification approach, the method of batch splitting will be described. Batch splitting allows the adaptation of load to capacity to reduce load scattering. After describing the method, it will be explicitly analyzed in the context of the logistic curve theory by Nyhuis using the stretch factor α1 in order to evaluate the impact of the method of batch splitting on load scattering and on logistic curves. The conclusion of this article will be to show how the methods and approaches presented can help companies in a turbulent environment to quantify the occurring work load scattering accurately and apply an efficient method for adjusting work load to capacity supply. In this way, the achievements of the logistical objectives are increased without causing additional costs.Keywords: batch splitting, production logistics, production planning and control, quantification, load scattering
Procedia PDF Downloads 393389 Compact, Lightweight, Low Cost, Rectangular Core Power Transformers
Authors: Abidin Tortum, Kubra Kocabey
Abstract:
One of the sectors where the competition is experienced at the highest level in the world is the transformer sector, and sales can be made with a limited profit margin. For this reason, manufacturers must develop cost-cutting designs to achieve higher profits. The use of rectangular cores and coils in transformer design is one of the methods that can be used to reduce costs. According to the best knowledge we have obtained, we think that we are the first company producing rectangular core power transformers in our country. BETA, to reduce the cost of this project, more compact products to reveal, as we know it to increase the alleviate and competitiveness of the product, will perform cored coil design and production rectangle for the first-time power transformers in Turkey. The transformer to be designed shall be 16 MVA, 33/11 kV voltage level. With the rectangular design of the transformer core and windings, no-load losses can be reduced. Also, the least costly transformer type is rectangular. However, short-circuit forces on rectangular windings do not affect every point of the windings in the same way. Whereas more force is applied inwards to the mid-points of the low-voltage winding, the opposite occurs in the high-voltage winding. Therefore, the windings tend to deteriorate in the event of a short circuit. While trying to reach the project objectives, the difficulties in the design should be overcome. Rectangular core transformers to be produced in our country offer a more compact structure than conventional transformers. In other words, both height and width were smaller. Thus, the reducer takes up less space in the center. Because the transformer boiler is smaller, less oil is used, and its weight is lower. Biotemp natural ester fluid is used in rectangular transformer and the cooling performance of this oil is analyzed. The cost was also reduced with the reduction of dimensions. The decrease in the amount of oil used has also increased the environmental friendliness of the developed product. Transportation costs have been reduced by reducing the total weight. The amount of carbon emissions generated during the transportation process is reduced. Since the low-voltage winding is wound with a foil winding technique, a more resistant structure is obtained against short circuit forces. No-load losses were lower due to the use of a rectangular core. The project was handled in three phases. In the first stage, preliminary research and designs were carried out. In the second stage, the prototype manufacturing of the transformer whose designs have been completed has been started. The prototype developed in the last stage has been subjected to routine, type and special tests.Keywords: rectangular core, power transformer, transformer, productivity
Procedia PDF Downloads 114388 Reactors with Effective Mixing as a Solutions for Micro-Biogas Plant
Authors: M. Zielinski, M. Debowski, P. Rusanowska, A. Glowacka-Gil, M. Zielinska, A. Cydzik-Kwiatkowska, J. Kazimierowicz
Abstract:
Technologies for the micro-biogas plant with heating and mixing systems are presented as a part of the Research Coordination for a Low-Cost Biomethane Production at Small and Medium Scale Applications (Record Biomap). The main objective of the Record Biomap project is to build a network of operators and scientific institutions interested in cooperation and the development of promising technologies in the sector of small and medium-sized biogas plants. The activities carried out in the project will bridge the gap between research and market and reduce the time of implementation of new, efficient technological and technical solutions. Reactor with simultaneously mixing and heating system is a concrete tank with a rectangular cross-section. In the reactor, heating is integrated with the mixing of substrate and anaerobic sludge. This reactor is solution dedicated for substrates with high solids content, which cannot be introduced to the reactor with pumps, even with positive displacement pumps. Substrates are poured to the reactor and then with a screw pump, they are mixed with anaerobic sludge. The pumped sludge, flowing through the screw pump, is simultaneously heated by a heat exchanger. The level of the fermentation sludge inside the reactor chamber is above the bottom edge of the cover. Cover of the reactor is equipped with the screw pump driver. Inside the reactor, an electric motor is installed that is driving a screw pump. The heated sludge circulates in the digester. The post-fermented sludge is collected using a drain well. The inlet to the drain well is below the level of the sludge in the digester. The biogas is discharged from the reactor by the biogas intake valve located on the cover. The technology is very useful for fermentation of lignocellulosic biomass and substrates with high content of dry mass (organic wastes). The other technology is a reactor for micro-biogas plant with a pressure mixing system. The reactor has a form of plastic or concrete tank with a circular cross-section. The effective mixing of sludge is ensured by profiled at 90° bottom of the tank. Substrates for fermentation are supplied by an inlet well. The inlet well is equipped with a cover that eliminates odour release. The introduction of a new portion of substrates is preceded by pumping of digestate to the disposal well. Optionally, digestate can gravitationally flow to digestate storage tank. The obtained biogas is discharged into the separator. The valve supplies biogas to the blower. The blower presses the biogas from the fermentation chamber in such a way as to facilitate the introduction of a new portion of substrates. Biogas is discharged from the reactor by valve that enables biogas removal but prevents suction from outside the reactor.Keywords: biogas, digestion, heating system, mixing system
Procedia PDF Downloads 144387 Site Suitability of Offshore Wind Energy: A Combination of Geographic Referenced Information and Analytic Hierarchy Process
Authors: Ayat-Allah Bouramdane
Abstract:
Power generation from offshore wind energy does not emit carbon dioxide or other air pollutants and therefore play a role in reducing greenhouse gas emissions from the energy sector. In addition, these systems are considered more efficient than onshore wind farms, as they generate electricity from the wind blowing across the sea, thanks to the higher wind speed and greater consistency in direction due to the lack of physical interference that the land or human-made objects can present. This means offshore installations require fewer turbines to produce the same amount of energy as onshore wind farms. However, offshore wind farms require more complex infrastructure to support them and, as a result, are more expensive to construct. In addition, higher wind speeds, strong seas, and accessibility issues makes offshore wind farms more challenging to maintain. This study uses a combination of Geographic Referenced Information (GRI) and Analytic Hierarchy Process (AHP) to identify the most suitable sites for offshore wind farm development in Morocco, with a particular focus on the Dakhla city. A range of environmental, socio-economic, and technical criteria are taken into account to solve this complex Multi-Criteria Decision-Making (MCDM) problem. Based on experts' knowledge, a pairwise comparison matrix at each level of the hierarchy is performed, and fourteen sub-criteria belong to the main criteria have been weighted to generate the site suitability of offshore wind plants and obtain an in-depth knowledge on unsuitable areas, and areas with low-, moderate-, high- and very high suitability. We find that wind speed is the most decisive criteria in offshore wind farm development, followed by bathymetry, while proximity to facilities, the sediment thickness, and the remaining parameters show much lower weightings rendering technical parameters most decisive in offshore wind farm development projects. We also discuss the potential of other marine renewable energy potential, in Morocco, such as wave and tidal energy. The proposed approach and analysis can help decision-makers and can be applied to other countries in order to support the site selection process of offshore wind farms.Keywords: analytic hierarchy process, dakhla, geographic referenced information, morocco, multi-criteria decision-making, offshore wind, site suitability
Procedia PDF Downloads 145386 New Insulation Material for Solar Thermal Collectors
Authors: Nabila Ihaddadene, Razika Ihaddadene, Abdelwahaab Betka
Abstract:
1973 energy crisis (rising oil prices) pushed the world to consider other alternative energy resources to existing conventional energies consisting predominantly of hydrocarbons. Renewable energies such as solar, the wind and geothermal have received renewed interest, especially to preserve nature ( the low-temperature rise of global environmental problems). Solar energy as an available, cheap and environmental friendly alternative source has various applications such as heating, cooling, drying, power generation, etc. In short, there is no life on earth without this enormous nuclear reactor, called the sun. Among available solar collector designs, flat plate collector (FPC) is low-temperature applications (heating water, space heating, etc.) due to its simple design and ease of manufacturing. Flat plate collectors are permanently fixed in position and do not track the sun (non-concentrating collectors). They operate by converting solar radiation into heat and transferring that heat to a working fluid (usually air, water, water plus antifreeze additive) flowing through them. An FPC generally consists of the main following components: glazing, absorber plate of high absorptivity, fluid tubes welded to or can be an integral part of the absorber plate, insulation and container or casing of the above-mentioned components. Insulation is of prime importance in thermal applications. There are three main families of insulation: mineral insulation; vegetal insulation and synthetic organic insulation. The old houses of the inhabitants of North Africa were built of brick made of composite material that is clay and straw. These homes are characterized by their thermal comfort; i.e. the air inside these houses is cool in summer and warm in winter. So, the material composed from clay and straw act as a thermal insulation. In this research document, the polystyrene used as insulation in the ET200 flat plate solar collector is replaced by the cheapest natural material which is clay and straw. Trials were carried out on a solar energy demonstration system (ET 200). This system contains a solar collector, water storage tank, a high power lamp simulating solar energy and a control and command cabinet. In the experimental device, the polystyrene is placed under the absorber plate and in the edges of the casing containing the components of the solar collector. In this work, we have replaced the polystyrene of the edges by the composite material. The use of the clay and straw as insulation instead of the polystyrene increases temperature difference (T2-T1) between the inlet and the outlet of the absorber by 0.9°C; thus increases the useful power transmitted to water in the solar collector. Tank Water is well heated when using the clay and straw as insulation. However, it is less heated when using the polystyrene as insulation. Clay and straw material improves also the performance of the solar collector by 5.77%. Thus, it is recommended to use this cheapest non-polluting material instead of synthetic insulation to improve the performance of the solar collector.Keywords: clay, insulation material, polystyrene, solar collector, straw
Procedia PDF Downloads 452385 Conservation Challenges of Wetlands Biodiversity in Northeast Region of Bangladesh
Authors: Anisuzzaman Khan, A. J. K. Masud
Abstract:
Bangladesh is the largest delta in the world predominantly comprising large network of rives and wetlands. Wetlands in Bangladesh are represented by inland freshwater, estuarine brakishwater and tidal salt-water coastal wetlands. Bangladesh possesses enormous area of wetlands including rivers and streams, freshwater lakes and marshes, haors, baors, beels, water storage reservoirs, fish ponds, flooded cultivated fields and estuarine systems with extensive mangrove swamps. The past, present, and future of Bangladesh, and its people’s livelihoods are intimately connected to its relationship with water and wetlands. More than 90% of the country’s total area consists of alluvial plains, crisscrossed by a complex network of rivers and their tributaries. Floodplains, beels (low-lying depressions in the floodplain), haors (deep depression) and baors (oxbow lakes) represent the inland freshwater wetlands. Over a third of Bangladesh could be termed as wetlands, considering rivers, estuaries, mangroves, floodplains, beels, baors and haors. The country’s wetland ecosystems also offer critical habitats for globally significant biological diversity. Of these the deeply flooded basins of north-east Bangladesh, known as haors, are a habitat of wide range of wild flora and fauna unique to Bangladesh. The haor basin lies within the districts of Sylhet, Sunamgonj, Netrokona, Kishoregonj, Habigonj, Moulvibazar, and Brahmanbaria in the Northeast region of Bangladesh comprises the floodplains of the Meghna tributaries and is characterized by the presence of numerous large, deeply flooded depressions, known as haors. It covers about around 8,568 km2 area of Bangladesh. The topography of the region is steep at around foothills in the north and slopes becoming mild and milder gradually at downstream towards south. Haor is a great reservoir of aquatic biological resources and acts as the ecological safety net to the nature as well as to the dwellers of the haor. But in reality, these areas are considered as wastelands and to make these wastelands into a productive one, a one sided plan has been implementing since long. The programme is popularly known as Flood Control, Drainage and Irrigation (FCDI) which is mainly devoted to increase the monoculture rice production. However, haor ecosystem is a multiple-resource base which demands an integrated sustainable development approach. The ongoing management approach is biased to only rice production through FCDI. Thus this primitive mode of action is diminishing other resources having more economic potential ever thought.Keywords: freshwater wetlands, biological diversity, biological resources, conservation and sustainable development
Procedia PDF Downloads 321384 Engineering Escherichia coli for Production of Short Chain Fatty Acid by Exploiting Fatty Acid Metabolic Pathway
Authors: Kamran Jawed, Anu Jose Mattam, Zia Fatma, Saima Wajid, Malik Z. Abdin, Syed Shams Yazdani
Abstract:
Worldwide demand of natural and sustainable fuels and chemicals have encouraged researchers to develop microbial platform for synthesis of short chain fatty acids as they are useful precursors to replace petroleum-based fuels and chemicals. In this study, we evaluated the role of fatty acid synthesis and β-oxidation cycle of Escherichia coli to produce butyric acid, a 4-carbon short chain fatty acid, with the help of three thioesterases, i.e., TesAT from Anaerococcus tetradius, TesBF from Bryantella formatexigens and TesBT from Bacteroides thetaiotaomicron. We found that E. coli strain transformed with gene for TesBT and grown in presence of 8 g/L glucose produced maximum butyric acid titer at 1.46 g/L, followed by that of TesBF at 0.85 g/L and TesAT at 0.12 g/L, indicating that these thioesterases were efficiently converting short chain fatty acyl-ACP intermediate of fatty acid synthesis pathway into the corresponding acid. The titer of butyric acid varied significantly depending upon the plasmid copy number and strain genotype. Deletion of genes for fatty acyl-CoA synthetase and acyl-CoA dehydrogenase, which are involved in initiating the fatty acid degradation cycle, and overexpression of FadR, which is a dual transcriptional regulator and exerts negative control over fatty acid degradation pathway, reduced up to 30% of butyric acid titer. This observation suggested that β-oxidation pathway is working synergistically with fatty acid synthesis pathway in production of butyric acid. Moreover, accelerating the fatty acid elongation cycle by overexpressing acetyl-CoA carboxyltransferase (Acc) and 3-hydroxy-acyl-ACP dehydratase (FabZ) or by deleting FabR, the transcription suppressor of elongation, did not improve the butyric acid titer, rather favored the long chain fatty acid production. Finally, a balance between cell growth and butyric acid production was achieved with the use of phosphorous limited growth medium and 14.3 g/L butyric acid, and 17.5 g/L total free fatty acids (FFAs) titer was achieved during fed-batch cultivation. We have engineered an E. coli strain which utilizes the intermediate of both fatty acid synthesis and degradation pathway, i.e. butyryl-ACP and -CoA, to produce butyric acid from glucose. The strategy used in this study resulted in highest reported titers of butyric acid and FFAs in engineered E. coli.Keywords: butenoic acid, butyric acid, Escherichia coli, fed-batch fermentation, short chain fatty acids, thioesterase
Procedia PDF Downloads 365383 Unification of Lactic Acid Bacteria and Aloe Vera for Healthy Gut
Authors: Pavitra Sharma, Anuradha Singh, Nupur Mathur
Abstract:
There exist more than 100 trillion bacteria in the digestive system of human-beings. Such bacteria are referred to as gut microbiota. Gut microbiota comprises around 75% of our immune system. The bacteria that comprise the gut microbiota are unique to every individual and their composition keeps changing with time owing to factors such as the host’s age, diet, genes, environment, and external medication. Of these factors, the variable easiest to control is one’s diet. By modulating one’s diet, one can ensure an optimal composition of the gut microbiota yielding several health benefits. Prebiotics and probiotics are two compounds that have been considered as viable options to modulate the host’s diet. Prebiotics are basically plant products that support the growth of good bacteria in the host’s gut. Examples include garden asparagus, aloe vera etc. Probiotics are living microorganisms that exist in our intestines and play an integral role in promoting digestive health and supporting our immune system in general. Examples include yogurt, kimchi, kombucha etc. In the context of modulating the host’s diet, the key attribute of prebiotics is that they support the growth of probiotics. By developing the right combination of prebiotics and probiotics, food products or supplements can be created to enhance the host’s health. An effective combination of prebiotics and probiotics that yields health benefits to the host is referred to as synbiotics. Synbiotics comprise of an optimal proportion of prebiotics and probiotics, their application benefits the host’s health more than the application of prebiotics and probiotics used in isolation. When applied to food supplements, synbiotics preserve the beneficial probiotic bacteria during storage period and during the bacteria’s passage through the intestinal tract. When applied to the gastrointestinal tract, the composition of the synbiotics assumes paramount importance. Reason being that for synbiotics to be effective in the gastrointestinal tract, the chosen probiotic must be able to survive in the stomach’s acidic environment and manifest tolerance towards bile and pancreatic secretions. Further, not every prebiotic stimulates the growth of a particular probiotic. The prebiotic chosen should be one that not only maintains 2 balance in the host’s digestive system, but also provides the required nutrition to probiotics. Hence in each application of synbiotics, the prebiotic-probiotic combination needs to be carefully selected. Once the combination is finalized, the exact proportion of prebiotics and probiotics to be used needs to be considered. When determining this proportion, only that amount of a prebiotic should be used that activates metabolism of the required number of probiotics. It was observed that while probiotics are active is both the small and large intestine, the effect of prebiotics is observed primarily in the large intestine. Hence in the host’s small intestine, synbiotics are likely to have the maximum efficacy. In small intestine, prebiotics not only assist in the growth of probiotics, but they also enable probiotics to exhibit a higher tolerance to pH levels, oxygenation, and intestinal temperatureKeywords: microbiota, probiotics, prebiotics, synbiotics
Procedia PDF Downloads 131