Search results for: Minimum Hydrotropic Concentration.
286 Grain Size Characteristics and Sediments Distribution in the Eastern Part of Lekki Lagoon
Authors: Mayowa Philips Ibitola, Abe Oluwaseun Banji, Olorunfemi Akinade-Solomon
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A total of 20 bottom sediment samples were collected from the Lekki Lagoon during the wet and dry season. The study was carried out to determine the textural characteristics, sediment distribution pattern and energy of transportation within the lagoon system. The sediment grain sizes and depth profiling was analyzed using dry sieving method and MATLAB algorithm for processing. The granulometric reveals fine grained sand both for the wet and dry season with an average mean value of 2.03 ϕ and -2.88 ϕ, respectively. Sediments were moderately sorted with an average inclusive standard deviation of 0.77 ϕ and -0.82 ϕ. Skewness varied from strongly coarse and near symmetrical 0.34- ϕ and 0.09 ϕ. The kurtosis average value was 0.87 ϕ and -1.4 ϕ (platykurtic and leptokurtic). Entirely, the bathymetry shows an average depth of 4.0 m. The deepest and shallowest area has a depth of 11.2 m and 0.5 m, respectively. High concentration of fine sand was observed at deep areas compared to the shallow areas during wet and dry season. Statistical parameter results show that the overall sediments are sorted, and deposited under low energy condition over a long distance. However, sediment distribution and sediment transport pattern of Lekki Lagoon is controlled by a low energy current and the down slope configuration of the bathymetry enhances the sorting and the deposition rate in the Lekki Lagoon.Keywords: Lekki Lagoon, marine sediment, bathymetry, grain size distribution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1045285 Effect of Landfill Leachate on Engineering Properties of Test Soil
Authors: S. A. Nta, M. J. Ayotamuno, I. J. Udom
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The work presents result of laboratory analysis of the effects of landfill leachate on engineering properties of test soil. The soil used for the present study was a sandy loam soil and acidic in nature. It was collected at a depth of 0.9 m. The landfill leachate used was collected from a hole dug some meters away from dumped solid waste and analyzed to identify the pollutants and its effect on engineering properties of the test soil. The test soil applied with landfill leachate was collected at 0.25 and 0.50 m radial distances at a depth of 0.15, 0.30, 0.45 and 0.60 m from the point of application of leachate after 50 days were the application of the leachate end and 80 days from the start of the experiment for laboratory analysis. Engineering properties such as particle size distribution, specific gravity, optimum moisture content, maximum dry density, unconfined compressive strength, liquid limit, plastic limit and shrinkage limit were considered. The concentration of various chemicals at 0.25 and 0.50 radial distances and 0.15, 0.30, 0.45 and 0.6 m depth from the point of application of leachate were different. This study founds the effect of landfill leachate on the engineering properties of soil. It can be concluded that, the type of soil, chemical composition of the leachate, infiltration rate, aquifers, ground water table etc., will have a major role on the area of influence zone of the pollutants in a landfill.
Keywords: Engineering properties of test soil, landfill leachate, Municipal solid waste.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 634284 Inversion Layer Effective Mobility Model for Pocket Implanted Nano Scale n-MOSFET
Authors: Muhibul Haque Bhuyan, Quazi D. M. Khosru
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Carriers scattering in the inversion channel of n- MOSFET dominates the drain current. This paper presents an effective electron mobility model for the pocket implanted nano scale n-MOSFET. The model is developed by using two linear pocket profiles at the source and drain edges. The channel is divided into three regions at source, drain and central part of the channel region. The total number of inversion layer charges is found for these three regions by numerical integration from source to drain ends and the number of depletion layer charges is found by using the effective doping concentration including pocket doping effects. These two charges are then used to find the effective normal electric field, which is used to find the effective mobility model incorporating the three scattering mechanisms, such as, Coulomb, phonon and surface roughness scatterings as well as the ballistic phenomena for the pocket implanted nano-scale n-MOSFET. The simulation results show that the derived mobility model produces the same results as found in the literatures.Keywords: Linear Pocket Profile, Pocket Implanted n-MOSFET, Effective Electric Field and Effective Mobility Model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1896283 Correlation of the Rate of Imperfect Competition and Profit in Banking Markets
Authors: Jan Cernohorsky
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This article aims to assess the evolution of imperfect competition in selected banking markets, in particular in the banking markets of Slovakia, Poland, Hungary, Slovenia and Croatia. Another objective is to assess the evolution of the relationship of imperfect competition and profit development in the banking markets. The article first provides an overview of literature on the topic. It then measures the degree of imperfect competition in individual markets using the Herfindahl-Hirschman Index. The commonly used indicator of total assets was chosen as an indicator. Based on this measurement, the individual banking sectors are categorized into theoretical definitions of the various types of imperfect competition - namely all surveyed banking sectors falling within the theoretical definition of monopolistic competition. Subsequently, using correlation analysis, i.e., the Pearson correlation coefficient, or the Spearman correlation coefficient, the connection between the evolution of imperfect competition and the development of the gross profit on selected banking markets was surveyed. It was found that with the exception of the banking market in Slovenia, where there is a positive correlation; there is no correlation between the evolution of imperfect competition and profit development in the selected markets. This means a recommendation for the regulators that it is not appropriate to rationalize a higher degree of regulation in granting banking licenses on the size of the profits attained in the banking market, as the relationship between the degree of concentration in the banking market and the amount of profit according to our measurements does not exist.Keywords: Banking system, imperfect competition, profitability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1665282 Analysis of Dust Particles in Snow Cover in the Surroundings of the City of Ostrava: Particle Size Distribution, Zeta Potential and Heavy Metal Content
Authors: Roman Marsalek
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In this paper, snow samples containing dust particles from several sampling points around the city of Ostrava were analyzed. The pH values of sampled snow were measured and solid particles analyzed. Particle size, zeta potential and content of selected heavy metals were determined in solid particles. The pH values of most samples lay in the slightly acid region. Mean values of particle size ranged from 290.5 to 620.5 nm. Zeta potential values varied between -5 and -26.5 mV. The following heavy metal concentration ranges were found: copper 0.08-0.75 mg/g, lead 0.05-0.9 mg/g, manganese 0.45-5.9 mg/g and iron 25.7-280.46 mg/g. The highest values of copper and lead were found in the vicinity of busy crossroads, and on the contrary, the highest levels of manganese and iron were detected close to a large steelworks. The proportion between pH values, zeta potentials, particle sizes and heavy metal contents was established. Zeta potential decreased with rising pH values and, simultaneously, heavy metal content in solid particles increased. At the same time, higher metal content corresponded to lower particle size.
Keywords: Dust, snow, zeta potential, particles size distribution, heavy metals.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1974281 Construction of Recombinant E.coli Expressing Fusion Protein to Produce 1,3-Propanediol
Authors: Rosarin Rujananon, Poonsuk Prasertsan, Amornrat Phongdara, Tanate Panrat, Jibin Sun, Sugima Rappert, An-Ping Zeng
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In this study, a synthetic pathway was created by assembling genes from Clostridium butyricum and Escherichia coli in different combinations. Among the genes were dhaB1 and dhaB2 from C. butyricum VPI1718 coding for glycerol dehydratase (GDHt) and its activator (GDHtAc), respectively, involved in the conversion of glycerol to 3-hydroxypropionaldehyde (3-HPA). The yqhD gene from E.coli BL21 was also included which codes for an NADPHdependent 1,3-propanediol oxidoreductase isoenzyme (PDORI) reducing 3-HPA to 1,3-propanediol (1,3-PD). Molecular modeling analysis indicated that the conformation of fusion protein of YQHD and DHAB1 was favorable for direct molecular channeling of the intermediate 3-HPA. According to the simulation results, the yqhD and dhaB1 gene were assembled in the upstream of dhaB2 to express a fusion protein, yielding the recombinant strain E. coliBL21 (DE3)//pET22b+::yqhD-dhaB1_dhaB2 (strain BP41Y3). Strain BP41Y3 gave 10-fold higher 1,3-PD concentration than E. coliBL21 (DE3)//pET22b+::yqhD-dhaB1_dhaB2 (strain BP31Y2) expressing the recombinant enzymes simultaneously but in a non-fusion mode. This is the first report using a gene fusion approach to enhance the biological conversion of glycerol to the value added compound 1,3- PD.Keywords: Recombinant E.coli, 1, 3-propanediol, glycerol, fusion protein.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2000280 A Study on Leaching Behavior of Na, Ca and K Using Column Leach Test
Authors: Barman P.J, Kartha S A, Gupta S, Pradhan B.
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Column leach test has been performed to examine the behavior of leaching of sodium, calcium and potassium in landfills. In the column leach apparatus, two different layers of contaminated and uncontaminated soils of different height ratios (ratio of depth of contaminated soil to the depth of uncontaminated soil) are taken. Water is poured from an overhead tank at a particular flowrate to the inlet of the soil column for a certain ponding depth over the contaminated soil. Subsequent infiltration causes leaching and the leachates are collected from the bottom of the column. The concentrations of Na, Ca and K in the leachate are measured using flame photometry. The experiments are further extended by changing the rates of flow from the overhead tank to the inlet of the column in achieving the same ponding depth. The experiments are performed for different scenarios in which the height ratios are altered and the variations of concentrations of Na, Ca, and K are observed. The study brings an estimation of leaching in landfill sites for different heights and precipitation intensity where a ponding depth is maintained over the landfill. It has been observed that the leaching behavior of Na, Ca, and K are not similar. Calcium exhibits highest amount of leaching compared to Sodium and Potassium under similar experimental conditions.Keywords: Column leaching, flow rate, uncontaminated soil, contaminated soil, concentration, height ratio.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2322279 Mercury Removal Using Pseudomonas putida (ATTC 49128): Effect of Acclimatization Time, Speed and Temperature of Incubator Shaker
Authors: A. A. M. Azoddein, R. M. Yunus, N. M. Sulaiman, A. B. Bustary, K. Sabar
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Microbes have been used to solve environmental problems for many years. The role of microorganism to sequester, precipitate or alter the oxidation state of various heavy metals has been extensively studied. Treatment using microorganism interacts with toxic metal are very diverse. The purpose of this research is to remove the mercury using Pseudomonas putida (P. putida), pure culture ATTC 49128 at optimum growth parameters such as techniques of culture, acclimatization time and speed of incubator shaker. Thus, in this study, the optimum growth parameters of P. putida were obtained to achieve the maximum of mercury removal. Based on the optimum parameters of P. putida for specific growth rate, the removal of two different mercury concentration, 1 ppm and 4 ppm were studied. From mercury nitrate solution, a mercuryresistant bacterial strain which is able to reduce from ionic mercury to metallic mercury was used to reduce ionic mercury. The overall levels of mercury removal in this study were between 80% and 89%. The information obtained in this study is of fundamental for understanding of the survival of P. putida ATTC 49128 in mercury solution. Thus, microbial mercury removal is a potential bioremediation for wastewater especially in petrochemical industries in Malaysia.Keywords: Pseudomonas putida, growth kinetic, biosorption, mercury, petrochemical wastewater.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2409278 A Study on Flammability of Bio Oil Combustible Vapour Mixtures
Authors: Mohanad El-Harbawi, Nurul Amirah Hanim Bt. Umar, Norizan Ali, Yoshimitsu Uemura
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Study of fire and explosion is very important mainly in oil and gas industries due to several accidents which have been reported in the past and present. In this work, we have investigated the flammability of bio oil vapour mixtures. This mixture may contribute to fire during the storage and transportation process. Bio oil sample derived from Palm Kernell shell was analysed using Gas Chromatography Mass Spectrometry (GC-MS) to examine the composition of the sample. Mole fractions of 12 selected components in the liquid phase were obtained from the GC-FID data and used to calculate mole fractions of components in the gas phase via modified Raoult-s law. Lower Flammability Limits (LFLs) and Upper Flammability Limits (UFLs) for individual components were obtained from published literature. However, stoichiometric concentration method was used to calculate the flammability limits of some components which their flammability limit values are not available in the literature. The LFL and UFL values for the mixture were calculated using the Le Chatelier equation. The LFLmix and UFLmix values were used to construct a flammability diagram and subsequently used to determine the flammability of the mixture. The findings of this study can be used to propose suitable inherently safer method to prevent the flammable mixture from occurring and to minimizing the loss of properties, business, and life due to fire accidents in bio oil productions.Keywords: Gas chromatography, compositions, lower and upper flammability limits (LFL & UFL), flammability diagram.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3416277 Using the Monte Carlo Simulation to Predict the Assembly Yield
Authors: C. Chahin, M. C. Hsu, Y. H. Lin, C. Y. Huang
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Electronics Products that achieve high levels of integrated communications, computing and entertainment, multimedia features in small, stylish and robust new form factors are winning in the market place. Due to the high costs that an industry may undergo and how a high yield is directly proportional to high profits, IC (Integrated Circuit) manufacturers struggle to maximize yield, but today-s customers demand miniaturization, low costs, high performance and excellent reliability making the yield maximization a never ending research of an enhanced assembly process. With factors such as minimum tolerances, tighter parameter variations a systematic approach is needed in order to predict the assembly process. In order to evaluate the quality of upcoming circuits, yield models are used which not only predict manufacturing costs but also provide vital information in order to ease the process of correction when the yields fall below expectations. For an IC manufacturer to obtain higher assembly yields all factors such as boards, placement, components, the material from which the components are made of and processes must be taken into consideration. Effective placement yield depends heavily on machine accuracy and the vision of the system which needs the ability to recognize the features on the board and component to place the device accurately on the pads and bumps of the PCB. There are currently two methods for accurate positioning, using the edge of the package and using solder ball locations also called footprints. The only assumption that a yield model makes is that all boards and devices are completely functional. This paper will focus on the Monte Carlo method which consists in a class of computational algorithms (information processed algorithms) which depends on repeated random samplings in order to compute the results. This method utilized in order to recreate the simulation of placement and assembly processes within a production line.
Keywords: Monte Carlo simulation, placement yield, PCBcharacterization, electronics assembly
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2158276 Thermal Stability and Crystallization Behaviour of Modified ABS/PP Nanocomposites
Authors: Marianna I. Triantou, Petroula A. Tarantili
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In this research work, poly (acrylonitrile-butadienestyrene)/ polypropylene (ABS/PP) blends were processed by melt compounding in a twin-screw extruder. Upgrading of the thermal characteristics of the obtained materials was attempted by the incorporation of organically modified montmorillonite (OMMT), as well as, by the addition of two types of compatibilizers; polypropylene grafted with maleic anhydride (PP-g-MAH) and ABS grafted with maleic anhydride (ABS-g-MAH). The effect of the above treatments was investigated separately and in combination. Increasing the PP content in ABS matrix seems to increase the thermal stability of their blend and the glass transition temperature (Tg) of SAN phase of ABS. From the other part, the addition of ABS to PP promotes the formation of its β-phase, which is maximum at 30 wt% ABS concentration, and increases the crystallization temperature (Tc) of PP. In addition, it increases the crystallization rate of PP.The β-phase of PP in ABS/PP blends is reduced by the addition of compatibilizers or/and organoclay reinforcement. The incorporation of compatibilizers increases the thermal stability of PP and reduces its melting (ΔΗm) and crystallization (ΔΗc) enthalpies. Furthermore it decreases slightly the Tgs of PP and SAN phases of ABS/PP blends. Regarding the storage modulus of the ABS/PP blends, it presents a change in their behavior at about 10°C and return to their initial behavior at ~110°C. The incorporation of OMMT to no compatibilized and compatibilized ABS/PP blends enhances their storage modulus.
Keywords: Acrylonitrile, butadiene, styrene terpolymer, compatibilizer, organoclay, polypropylene.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2901275 Result Validation Analysis of Steel Testing Machines
Authors: Wasiu O. Ajagbe, Habeeb O. Hamzat, Waris A. Adebisi
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Structural failures occur due to a number of reasons. These may include under design, poor workmanship, substandard materials, misleading laboratory tests and lots more. Reinforcing steel bar is an important construction material, hence its properties must be accurately known before being utilized in construction. Understanding this property involves carrying out mechanical tests prior to design and during construction to ascertain correlation using steel testing machine which is usually not readily available due to the location of project. This study was conducted to determine the reliability of reinforcing steel testing machines. Reconnaissance survey was conducted to identify laboratories where yield and ultimate tensile strengths tests can be carried out. Six laboratories were identified within Ibadan and environs. However, only four were functional at the time of the study. Three steel samples were tested for yield and tensile strengths, using a steel testing machine, at each of the four laboratories (LM, LO, LP and LS). The yield and tensile strength results obtained from the laboratories were compared with the manufacturer’s specification using a reliability analysis programme. Structured questionnaire was administered to the operators in each laboratory to consider their impact on the test results. The average value of manufacturers’ tensile strength and yield strength are 673.7 N/mm2 and 559.7 N/mm2 respectively. The tensile strength obtained from the four laboratories LM, LO, LP and LS are given as 579.4, 652.7, 646.0 and 649.9 N/mm2 respectively while their yield strengths respectively are 453.3, 597.0, 550.7 and 564.7 N/mm2. Minimum tensile to yield strength ratio is 1.08 for BS 4449: 2005 and 1.15 for ASTM A615. Tensile to yield strength ratio from the four laboratories are 1.28, 1.09, 1.17 and 1.15 for LM, LO, LP and LS respectively. The tensile to yield strength ratio shows that the result obtained from all the laboratories meet the code requirements used for the test. The result of the reliability test shows varying level of reliability between the manufacturers’ specification and the result obtained from the laboratories. Three of the laboratories; LO, LS and LP have high value of reliability with the manufacturer i.e. 0.798, 0.866 and 0.712 respectively. The fourth laboratory, LM has a reliability value of 0.100. Steel test should be carried out in a laboratory using the same code in which the structural design was carried out. More emphasis should be laid on the importance of code provisions.
Keywords: Reinforcing steel bars, reliability analysis, tensile strength, universal testing machine, yield strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 740274 Effect of Superplasticizer and NaOH Molarity on Workability, Compressive Strength and Microstructure Properties of Self-Compacting Geopolymer Concrete
Authors: M. Fadhil Nuruddin, Samuel Demie, M. Fareed Ahmed, Nasir Shafiq
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The research investigates the effects of super plasticizer and molarity of sodium hydroxide alkaline solution on the workability, microstructure and compressive strength of self compacting geopolymer concrete (SCGC). SCGC is an improved way of concreting execution that does not require compaction and is made by complete elimination of ordinary Portland cement content. The parameters studied were superplasticizer (SP) dosage and molarity of NaOH solution. SCGC were synthesized from low calcium fly ash, activated by combinations of sodium hydroxide and sodium silicate solutions, and by incorporation of superplasticizer for self compactability. The workability properties such as filling ability, passing ability and resistance to segregation were assessed using slump flow, T-50, V-funnel, L-Box and J-ring test methods. It was found that the essential workability requirements for self compactability according to EFNARC were satisfied. Results showed that the workability and compressive strength improved with the increase in superplasticizer dosage. An increase in strength and a decrease in workability of these concrete samples were observed with the increase in molarity of NaOH solution from 8M to 14M. Improvement of interfacial transition zone (ITZ) and micro structure with the increase of SP and increase of concentration from 8M to 12M were also identified.
Keywords: Compressive strength, Fly ash, Geopolymer concrete, Workability
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4704273 Laboratory Evaluation of Bacillus subtilis Bioactivity on Musca domestica (Linn) (Diptera: Muscidae) Larvae from Poultry Farms in South Western Nigeria
Authors: Funmilola O. Omoya
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Muscid flies are known to be vectors of disease agents and species that annoy humans and domesticated animals. An example of these flies is Musca domestica (house fly) whose adult and immature stages occur in a variety of filthy organic substances including household garbage and animal manures. They contribute to microbial contamination of foods. It is therefore imperative to control these flies as a result of their role in Public health. The second and third instars of Musca domestica (Linn) were infected with varying cell loads of Bacillus subtilis in vitro for a period of 48 hours to evaluate its larvicidal activities. Mortality of the larvae increased with incubation period after treatment with the varying cell loads. Investigation revealed that the second instars larvae were more susceptible to treatment than the third instars treatments. Values obtained from the third instar group were significantly different (P<0.05) from those obtained from the second instars group in all the treatments. Lethal concentration (LC50) at 24 hours for 2nd instars was 2.35 while LC50 at 48 hours was 4.31.This study revealed that Bacillus subtilis possess good larvicidal potential for use in the control of Musca domestica in poultry farms.
Keywords: Bacillus subtilis, larvicidal activities, Musca domestica, poultry farms.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2223272 Effective Charge Coupling in Low Dimensional Doped Quantum Antiferromagnets
Authors: Suraka Bhattacharjee, Ranjan Chaudhury
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The interaction between the charge degrees of freedom for itinerant antiferromagnets is investigated in terms of generalized charge stiffness constant corresponding to nearest neighbour t-J model and t1-t2-t3-J model. The low dimensional hole doped antiferromagnets are the well known systems that can be described by the t-J-like models. Accordingly, we have used these models to investigate the fermionic pairing possibilities and the coupling between the itinerant charge degrees of freedom. A detailed comparison between spin and charge couplings highlights that the charge and spin couplings show very similar behaviour in the over-doped region, whereas, they show completely different trends in the lower doping regimes. Moreover, a qualitative equivalence between generalized charge stiffness and effective Coulomb interaction is also established based on the comparisons with other theoretical and experimental results. Thus it is obvious that the enhanced possibility of fermionic pairing is inherent in the reduction of Coulomb repulsion with increase in doping concentration. However, the increased possibility can not give rise to pairing without the presence of any other pair producing mechanism outside the t-J model. Therefore, one can conclude that the t-J-like models themselves solely are not capable of producing conventional momentum-based superconducting pairing on their own.Keywords: Generalized charge stiffness constant, charge coupling, effective Coulomb interaction, t-J-like models, momentum-space pairing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 604271 Effects of Energy Consumption on Indoor Air Quality
Authors: M. Raatikainen, J-P. Skön, M. Johansson, K. Leiviskä, M. Kolehmainen
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Continuous measurements and multivariate methods are applied in researching the effects of energy consumption on indoor air quality (IAQ) in a Finnish one-family house. Measured data used in this study was collected continuously in a house in Kuopio, Eastern Finland, during fourteen months long period. Consumption parameters measured were the consumptions of district heat, electricity and water. Indoor parameters gathered were temperature, relative humidity (RH), the concentrations of carbon dioxide (CO2) and carbon monoxide (CO) and differential air pressure. In this study, self-organizing map (SOM) and Sammon's mapping were applied to resolve the effects of energy consumption on indoor air quality. Namely, the SOM was qualified as a suitable method having a property to summarize the multivariable dependencies into easily observable two-dimensional map. Accompanying that, the Sammon's mapping method was used to cluster pre-processed data to find similarities of the variables, expressing distances and groups in the data. The methods used were able to distinguish 7 different clusters characterizing indoor air quality and energy efficiency in the study house. The results indicate, that the cost implications in euros of heating and electricity energy vary according to the differential pressure, concentration of carbon dioxide, temperature and season.
Keywords: Indoor air quality, Energy efficiency, Self- organizing map, Sammon's mapping
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1867270 Forecast of Polyethylene Properties in the Gas Phase Polymerization Aided by Neural Network
Authors: Nasrin Bakhshizadeh, Ashkan Forootan
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A major problem that affects the quality control of polymer in the industrial polymerization is the lack of suitable on-line measurement tools to evaluate the properties of the polymer such as melt and density indices. Controlling the polymerization in ordinary method is performed manually by taking samples, measuring the quality of polymer in the lab and registry of results. This method is highly time consuming and leads to producing large number of incompatible products. An online application for estimating melt index and density proposed in this study is a neural network based on the input-output data of the polyethylene production plant. Temperature, the level of reactors' bed, the intensity of ethylene mass flow, hydrogen and butene-1, the molar concentration of ethylene, hydrogen and butene-1 are used for the process to establish the neural model. The neural network is taught based on the actual operational data and back-propagation and Levenberg-Marquart techniques. The simulated results indicate that the neural network process model established with three layers (one hidden layer) for forecasting the density and the four layers for the melt index is able to successfully predict those quality properties.
Keywords: Polyethylene, polymerization, density, melt index, neural network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 672269 Thermophoresis Particle Precipitate on Heated Surfaces
Authors: Rebhi A. Damseh, H. M. Duwairi, Benbella A. Shannak
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This work deals with heat and mass transfer by steady laminar boundary layer flow of a Newtonian, viscous fluid over a vertical flat plate with variable surface heat flux embedded in a fluid saturated porous medium in the presence of thermophoresis particle deposition effect. The governing partial differential equations are transformed into no-similar form by using special transformation and solved numerically by using an implicit finite difference method. Many results are obtained and a representative set is displaced graphically to illustrate the influence of the various physical parameters on the wall thermophoresis deposition velocity and concentration profiles. It is found that the increasing of thermophoresis constant or temperature differences enhances heat transfer rates from vertical surfaces and increase wall thermophoresis velocities; this is due to favorable temperature gradients or buoyancy forces. It is also found that the effect of thermophoresis phenomena is more pronounced near pure natural convection heat transfer limit; because this phenomenon is directly a temperature gradient or buoyancy forces dependent. Comparisons with previously published work in the limits are performed and the results are found to be in excellent agreement.
Keywords: Thermophoresis, porous medium, variable surface heat flux.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2245268 A Numerical Study on the Seismic Performance of Built-Up Battened Columns
Authors: Sophia C. Alih, Mohammadreza Vafaei, Farnoud Rahimi Mansour, Nur Hajarul Falahi Abdul Halim
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Built-up columns have been widely employed by practice engineers in the design and construction of buildings and bridges. However, failures have been observed in this type of columns in previous seismic events. This study analyses the performance of built-up columns with different configurations of battens when it is subjected to seismic loads. Four columns with different size of battens were simulated and subjected to three different intensities of axial load along with a lateral cyclic load. Results indicate that the size of battens influences significantly the seismic behavior of columns. Lower shear capacity of battens results in higher ultimate strength and ductility for built-up columns. It is observed that intensity of axial load has a significant effect on the ultimate strength of columns, but it is less influential on the yield strength. For a given drift value, the stress level in the centroid of smaller size battens is significantly more than that of larger size battens signifying damage concentration in battens rather than chords. It is concluded that design of battens for shear demand lower than code specified values only slightly reduces initial stiffness of columns; however, it improves seismic performance of battened columns.Keywords: Battened column, built-up column, cyclic behavior, seismic design, steel column.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1291267 CFD Analysis of Multi-Phase Reacting Transport Phenomena in Discharge Process of Non-Aqueous Lithium-Air Battery
Authors: Jinliang Yuan, Jong-Sung Yu, Bengt Sundén
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A computational fluid dynamics (CFD) model is developed for rechargeable non-aqueous electrolyte lithium-air batteries with a partial opening for oxygen supply to the cathode. Multi-phase transport phenomena occurred in the battery are considered, including dissolved lithium ions and oxygen gas in the liquid electrolyte, solid-phase electron transfer in the porous functional materials and liquid-phase charge transport in the electrolyte. These transport processes are coupled with the electrochemical reactions at the active surfaces, and effects of discharge reaction-generated solid Li2O2 on the transport properties and the electrochemical reaction rate are evaluated and implemented in the model. The predicted results are discussed and analyzed in terms of the spatial and transient distribution of various parameters, such as local oxygen concentration, reaction rate, variable solid Li2O2 volume fraction and porosity, as well as the effective diffusion coefficients. It is found that the effect of the solid Li2O2 product deposited at the solid active surfaces is significant on the transport phenomena and the overall battery performance.
Keywords: Computational Fluid Dynamics (CFD), Modeling, Multi-phase, Transport Phenomena, Lithium-air battery.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2735266 Effects of School Facilities’ Mechanical and Plumbing Characteristics and Conditions on Student Attendance, Academic Performance and Health
Authors: Erica Cochran Hameen, Bobuchi Ken-Opurum, Shalini Priyadarshini, Berangere Lartigue, Sadhana Anath-Pisipati
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School districts throughout the United States are constantly seeking measures to improve test scores, reduce school absenteeism and improve indoor environmental quality. It is imperative to identify key building investments which will provide the largest benefits to schools in terms of improving the aforementioned factors. This study uses Analysis of Variance (ANOVA) tests to statistically evaluate the impact of a school building’s mechanical and plumbing characteristics on a child’s educational performance. The educational performance is measured via three indicators, i.e. test scores, suspensions, and absenteeism. The study investigated 125 New York City school facilities to determine the potential correlations between 50 mechanical and plumbing variables and the performance indicators. Key findings from the tests revealed that elementary schools with pneumatic systems in “good” condition have 48.8% lower percentages of students scoring at the minimum English Language Arts (ELA) competency level compared with those with no pneumatic system. Additionally, elementary schools with “unit heaters/cabinet heaters” in “good to fair” conditions have 1.1% higher attendance rates compared to schools with no “unit heaters/cabinet heaters” or those in inferior condition. Furthermore, elementary schools with air conditioning have 0.6% higher attendance rates compared to schools with no air conditioning, and those with interior floor drains in “good” condition have 1.8% higher attendance rates compared to schools with interior drains in inferior condition.
Keywords: Academic attendance and performance, mechanical and plumbing systems, schools, student health.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 628265 The Effect of Intermediate Stiffeners on Steel Reinforced Concrete Beams Behaviors
Authors: Teguh Sudibyo, Cheng-Cheng Chen
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Eight steel reinforced concrete beams (SRC), were fabricated and tested under earthquake type cyclic loading. The effectiveness of intermediate stiffeners, such as mid-span stiffener and plastic hinge zone stiffeners, in enhancing composite action and ductility of SRC beams was investigated. The effectiveness of strengthened beam-to-column (SBC) and weakened beam-to-column (WBC) connections in enhancing beam ductility was also studied. It was found that: (1) All the specimens possessed fairly high flexural ductility and were found adequate for structures in high seismic zones. (2) WBC connections induced stress concentration which caused extra damage to concrete near the flange tapering zone. This extra damage inhibited the flexural strength development and the ductility of the specimens with WBC connections to some extent. (3) Specimens with SBC connections demonstrated higher flexural strength and ductility compared to specimens with WBC connections. (4) The intermediate stiffeners, especially combination of plastic hinge zone stiffener and mid span stiffeners, have an obvious effect in enhancing the ductility of the beams with SBC connection.Keywords: Composite beam, concrete encased steel beam, steel reinforced concrete, stiffeners.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3844264 Experimental on Free and Forced Heat Transfer and Pressure Drop of Copper Oxide-Heat Transfer Oil Nanofluid in Horizontal and Inclined Microfin Tube
Authors: F. Hekmatipour, M. A. Akhavan-Behabadi, B. Sajadi
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In this paper, the combined free and forced convection heat transfer of the Copper Oxide-Heat Transfer Oil (CuO-HTO) nanofluid flow in horizontal and inclined microfin tubes is studied experimentally. The flow regime is laminar, and pipe surface temperature is constant. The effect of nanoparticle and microfin tube on the heat transfer rate is investigated with the Richardson number which is between 0.1 and 0.7. The results show an increasing nanoparticle concentration between 0% and 1.5% leads to enhance the combined free and forced convection heat transfer rate. According to the results, five correlations are proposed to provide estimating the free and forced heat transfer rate as the increasing Richardson number from 0.1 to 0.7. The maximum deviation of both correlations is less than 16%. Moreover, four correlations are suggested to assess the Nusselt number based on the Rayleigh number in inclined tubes from 1800000 to 7000000. The maximum deviation of the correlation is almost 16%. The Darcy friction factor of the nanofluid flow has been investigated. Furthermore, CuO-HTO nanofluid flows in inclined microfin tubes.
Keywords: Nanofluid; heat transfer oil; mixed convection; inclined tube; laminar flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 660263 Distribution of Gamma Radiation Levels in Core Sediment Samples in Gulf of Izmir: Eastern Aegean Sea, Turkey
Authors: D. Kurt, Z. U. Yümün, I. F. Barut, E. Kam
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Since the development of the industrial revolution, industrial plants and settlements have spread widely along coastlines. This concentration of development brings environmental pollution to the seas. This study focuses on the Gulf of Izmir, a natural gulf of the Eastern Aegean Sea, located west of Turkey. Investigating marine current sediment is extremely important to detect pollution. This study considered natural radioactivity pollution of the marine environment. Ground drilling cores (the depth of each sediment is different) were taken from four different locations in the Gulf of izmir, Karşıyaka (12.5-13.5 m), Inciralti (6.5-7.5 m), Cesmealti (4.5-5 m) and Bayrakli (10-12 m). These sediment cores were put in preserving bags with weight around 1 kg, and were dried at room temperature to remove moisture. The samples were then sieved into fine powder (100 mesh), and these samples were relocated to 1000 mL polyethylene Marinelli beakers. The prepared sediments were stored for 40 days to reach radioactive equilibrium between uranium and thorium. Gamma spectrometry measurement of each sample was made using an HPGe (High-Purity Germanium) semiconductor detector. In this study, the results display that the average concentrations of the activity values are 8.4 ± 0.23 Bq kg-1, 19.6 ± 0.51 Bq kg-1, 8 ± 0.96 Bq kg-1, 1.93 ± 0.3 Bq kg-1, and 77.4 ± 0.96 Bq kg-1, respectively.
Keywords: Gamma, Gulf of Izmir, Eastern Aegean Sea, Turkey, natural radionuclides, pollution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1230262 Comparative Analysis of Pit Composting and Vermicomposting in a Tropical Environment
Authors: E. Ewemoje Oluseyi, T. A. Ewemoje, A. A. Adedeji
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Biodegradable solid waste disposal and management has been a major problem in Nigeria and indiscriminate dumping of this waste either into watercourses or drains has led to environmental hazards affecting public health. The study investigated the nutrients level of pit composting and vermicomposting. Wooden bins 60 cm × 30 cm × 30 cm3 in size were constructed and bedding materials (sawdust, egg shell, paper and grasses) and red worms (Eisenia fetida) introduced to facilitate the free movement and protection of the worms against harsh weather. A pit of 100 cm × 100 cm × 100 cm3 was dug and worms were introduced into the pit, which was turned every two weeks. Food waste was fed to the red worms in the bin and pit, respectively. The composts were harvested after 100 days and analysed. The analyses gave: nitrogen has average value 0.87 % and 1.29 %; phosphorus 0.66 % and 1.78 %; potassium 4.35 % and 6.27 % for the pit and vermicomposting, respectively. Higher nutrient status of vermicomposting over pit composting may be attributed to the secretions in the intestinal tracts of worms which are more readily available for plant growth. However, iron and aluminium were more in the pit compost than the vermin compost and this may be attributed to the iron and aluminium already present in the soil before the composting took place. Other nutrients in ppm concentrations were aluminium 4,999.50 and 3,989.33; iron 2,131.83 and 633.40 for the pit and vermicomposting, respectively. These nutrients are only needed by plants in small quantities. Hence, vermicomposting has the higher concentration of essential nutrients necessary for healthy plant growth.
Keywords: Food wastes, pit composting, plant nutrient status, tropical environment, vermicomposting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1828261 Identification of Active Phytocomponents in the Ethyl Acetate Extract of Glycosmis pentaphylla Retz. DC by Using GC-MS
Authors: M. Sivakumar, D. Chamundeeswari
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Glycosmis pentaphylla is one of the medicinally important plants belonging to the family Rutaceae, commonly known as “Anam or Panal” in Tamil. Traditionally, leaves are useful in fever, hepatopathy, eczema, skin disease, helminthiasis, wounds, and erysipelas. The fruits are sweet and are useful in vitiated conditions of vata, kapha, cough, and bronchitis. The roots are good for facial inflammations, rheumatism, jaundice, and anemia. The preliminary phytochemical investigations indicated the presence of alkaloids, terpenoids, flavonoids, tannins, sugar, glycoside, and phenolic compounds. In the present study, the root part of Glycosmis pentaphylla was used, and the root was collected from Western Ghats of South India. The root was sun/shade dried and pulverized to powder in a mechanical grinder. The powder was successively extracted with various solvents, and the ethyl acetate extract of Glycosmis pentaphylla has been subjected to the GC-MS analysis. Amongst the 46 chemical constituents identified from this plant, three major phytoconstituents were reported for the first time. Marmesin, a furanocumarin compound with the chemical structure 7H-Furo (3,2-G) (1)Benzopyran-7-one,2,3–dihydro–2 - (1-Hydroxy-1methylethyl)-(s) is one of the three compounds identified for the first time at the concentration of 11-60% in ethyl acetate extract of Glycosmis pentaphylla. Others include, Beta.-Fagarine (4.71%) and Paverine (13.08%).
Keywords: Ethyl acetate extract, Glycosmis pentaphylla, GC-MS analysis, phytochemicals.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1676260 Biodiesel Production from Broiler Chicken Waste
Authors: John Abraham, Ramesh Saravana Kumar, Francis Xavier, Deepak Mathew
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Broiler slaughter waste has become a major source of pollution throughout the world. Utilization of broiler slaughter waste by dry rendering process produced Rendered Chicken Oil (RCO), a cheap raw material for biodiesel production and Carcass Meal a feed ingredient for pets and fishes. Conversion of RCO into biodiesel may open new vistas for generating wealth from waste besides controlling the major havoc of environmental pollution. A two-step process to convert RCO to good quality Biodiesel was invented. Acid catalysed esterification of FFA followed by base catalysed transesterification of triglycerides was carried out after meticulously standardizing the methanol molar ratio, catalyst concentration, reaction temperature, and reaction time to obtain the maximum biodiesel yield of 97.62% and lowest glycerol yield of 6.96%. RCO biodiesel blend was tested in a CRDI diesel engine. The results revealed that the blending of commercial diesel with 20% RCO biodiesel (B20) lead to less engine wear, a quieter engine and better fuel economy. The better lubricating qualities of RCO B20 prevented over heating of engine, which prolongs the engine life. RCO B20 can reduce the import of crude oil and substantially reduce the engine emissions as proved by significantly lower smoke levels, thus mitigating climatic changes.Keywords: Biodiesel, Broiler Waste, Engine Testing, Rendered Chicken Oil.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5491259 Use of Caffeine and Human Pharmaceutical Compounds to Identify Sewage Contamination
Authors: Jingming Wu, Junqi Yue, Ruikang Hu, Zhaoguang Yang, Lifeng Zhang
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Fecal coliform bacteria are widely used as indicators of sewage contamination in surface water. However, there are some disadvantages in these microbial techniques including time consuming (18-48h) and inability in discriminating between human and animal fecal material sources. Therefore, it is necessary to seek a more specific indicator of human sanitary waste. In this study, the feasibility was investigated to apply caffeine and human pharmaceutical compounds to identify the human-source contamination. The correlation between caffeine and fecal coliform was also explored. Surface water samples were collected from upstream, middle-stream and downstream points respectively, along Rochor Canal, as well as 8 locations of Marina Bay. Results indicate that caffeine is a suitable chemical tracer in Singapore because of its easy detection (in the range of 0.30-2.0 ng/mL), compared with other chemicals monitored. Relative low concentrations of human pharmaceutical compounds (< 0.07 ng/mL) in Rochor Canal and Marina Bay water samples make them hard to be detected and difficult to be chemical tracer. However, their existence can help to validate sewage contamination. In addition, it was discovered the high correlation exists between caffeine concentration and fecal coliform density in the Rochor Canal water samples, demonstrating that caffeine is highly related to the human-source contamination.Keywords: Caffeine, Human Pharmaceutical Compounds, Chemical Tracer, Sewage Contamination.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2504258 Computer Models of the Vestibular Head Tilt Response, and Their Relationship to EVestG and Meniere's Disease
Authors: Daniel Heibert, Brian Lithgow, Kerry Hourigan
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This paper attempts to explain response components of Electrovestibulography (EVestG) using a computer simulation of a three-canal model of the vestibular system. EVestG is a potentially new diagnostic method for Meniere's disease. EVestG is a variant of Electrocochleography (ECOG), which has been used as a standard method for diagnosing Meniere's disease - it can be used to measure the SP/AP ratio, where an SP/AP ratio greater than 0.4-0.5 is indicative of Meniere-s Disease. In EVestG, an applied head tilt replaces the acoustic stimulus of ECOG. The EVestG output is also an SP/AP type plot, where SP is the summing potential, and AP is the action potential amplitude. AP is thought of as being proportional to the size of a population of afferents in an excitatory neural firing state. A simulation of the fluid volume displacement in the vestibular labyrinth in response to various types of head tilts (ipsilateral, backwards and horizontal rotation) was performed, and a simple neural model based on these simulations developed. The simple neural model shows that the change in firing rate of the utricle is much larger in magnitude than the change in firing rates of all three semi-circular canals following a head tilt (except in a horizontal rotation). The data suggests that the change in utricular firing rate is a minimum 2-3 orders of magnitude larger than changes in firing rates of the canals during ipsilateral/backward tilts. Based on these results, the neural response recorded by the electrode in our EVestG recordings is expected to be dominated by the utricle in ipsilateral/backward tilts (It is important to note that the effect of the saccule and efferent signals were not taken into account in this model). If the utricle response dominates the EVestG recordings as the modeling results suggest, then EVestG has the potential to diagnose utricular hair cell damage due to a viral infection (which has been cited as one possible cause of Meniere's Disease).
Keywords: Diagnostic, endolymph hydrops, Meniere's disease, modeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1508257 Phage Capsid for Efficient Delivery of Cytotoxic Drugs
Authors: Simona Dostalova, Ana Maria Jimenez Jimenez, Marketa Vaculovicova, Vojtech Adam, Rene Kizek
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Various nanomaterials can be used as a drug delivery vehicles in nanomedicine, called nanocarriers. They can either be organic or inorganic, synthetic or natural-based. Although synthetic nanocarriers are easier to produce, they can often be toxic for the organism and thus not suitable for use in treatment. From naturalbased nanocarriers, the most commonly used are protein cages or viral capsids. In this work, virus bacteriophage λ was used for delivery of different cytotoxic drugs (cisplatin, carboplatin, oxaliplatin and doxorubicin). Large quantities of phage λ were obtained from phage λ-producing strain of E. coli cultivated in medium with 0.2% maltose. After killing of E. coli with chloroform and its removal by centrifugation, the phage was concentrated by ultracentrifugation at 130 000×g and 4°C for 3 h. The encapsulation of the drugs was performed by infusion method and four different concentrations of the drugs were encapsulated (200; 100; 50; 25 μg·mL-1). Free drug molecules were removed by filtration. The encapsulation was verified using the absorbance for doxorubicin and atomic absorption spectrometry for platinum cytostatics. The amount of encapsulated drug linearly increased with the increasing concentration of applied drug with the determination coefficient R2=0.989 for doxorubicin; R2=0.967 for cisplatin; R2=0.989 for carboplatin and R2=0.996 for oxaliplatin. The overall encapsulation efficiency was calculated as 50% for doxorubicin; 8% for cisplatin; 6% for carboplatin and 10% for oxaliplatin.Keywords: Bacteriophage λ, doxorubicin, platinum cytostatics, protein-based nanocarrier, viral capsid.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1757