Search results for: density measurements
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5942

Search results for: density measurements

3362 Thin and Flexible Zn-Air Battery by Inexpensive Screen Printing Technique

Authors: Sira Suren, Soorathep Kheawhom

Abstract:

This work focuses the development of thin and flexible zinc-air battery. The battery with an overall thickness of about 300 μm was fabricated by an inexpensive screen-printing technique. Commercial nano-silver ink was used as both current collectors and catalyst layer. Carbon black ink was used to fabricate cathode electrode. Polypropylene membrane was used as the cathode substrate and separator. 9 M KOH was used as the electrolyte. A mixture of Zn powder and ZnO was used to prepare the anode electrode. Types of conductive materials (Bi2O3, Na2O3Si and carbon black) for the anode and its concentration were investigated. Results showed that the battery using 29% carbon black showed the best performance. The open-circuit voltage and energy density observed were 1.6 V and 694 Wh/kg, respectively. When the battery was discharged at 10 mA/cm2, the potential voltage observed was 1.35 V. Furthermore, the battery was tested for its flexibility. Upon bending, no significant loss in performance was observed.

Keywords: flexible, Gel Electrolyte, screen printing, thin battery, Zn-Air battery

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3361 An Experimental Comparative Study of SI Engine Performance and Emission Characteristics Fuelled with Various Gasoline-Alcohol Blends

Authors: M. Mourad, K. Abdelgawwad

Abstract:

This experimental investigation aimed to determine the influence of using different types of alcohol and gasoline blends such as ethanol - butanol - propanol on the performance of spark ignition engine. The experimental work studied the effect of various fuel blends such as ethanol – butanol/gasoline and propanol/gasoline with two rates of 15% and 20%, at different operating conditions (engine speed and loads), on engine performance emission characteristics. Laboratory experiments are carried out on a four-cylinder spark ignition (SI) engine. In this practical study, all considerations and precautions are taken into account to ensure the quality and accuracy of practical experiments and different measurements. The results show that the performance of the engine improved significantly in the case of ethanol/butanol-gasoline blends. The results also indicated that the engine emitted pollutants such as CO, hydrocarbon (HC) for alcohol fuel blends compared to base gasoline NOx emission increased for different fuel blends either ethanol/butanol-gasoline or propanol-gasoline fuel blend.

Keywords: gasoline engine, performance, emission, fuel blends

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3360 Charge Carrier Mobility Dependent Open-Circuit Voltage in Organic and Hybrid Solar Cells

Authors: David Ompong, Jai Singh

Abstract:

A better understanding of the open-circuit voltage (Voc) related losses in organic solar cells (OSCs) is desirable in order to assess the photovoltaic performance of these devices. We have derived Voc as a function of charge carrier mobilities (μe and μh) for organic and hybrid solar cells by optimizing the drift-diffusion current density. The optimum Voc thus obtained depends on the energy difference between the highest occupied molecular orbital (HOMO) level and the quasi-Fermi level of holes of the donor material. We have found that the Voc depends on the ratio of the electron (μe) and hole (μh) mobilities and when μh > μe the Voc increases. The most important loss term in the Voc arises from the energetics of the donor and acceptor materials, which will be discussed in detail in this paper.

Keywords: charge carrier mobility, open-circuit voltage, organic solar cells, quasi-fermi levels

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3359 The Power of in situ Characterization Techniques in Heterogeneous Catalysis: A Case Study of Deacon Reaction

Authors: Ramzi Farra, Detre Teschner, Marc Willinger, Robert Schlögl

Abstract:

Introduction: The conventional approach of characterizing solid catalysts under static conditions, i.e., before and after reaction, does not provide sufficient knowledge on the physicochemical processes occurring under dynamic conditions at the molecular level. Hence, the necessity of improving new in situ characterizing techniques with the potential of being used under real catalytic reaction conditions is highly desirable. In situ Prompt Gamma Activation Analysis (PGAA) is a rapidly developing chemical analytical technique that enables us experimentally to assess the coverage of surface species under catalytic turnover and correlate these with the reactivity. The catalytic HCl oxidation (Deacon reaction) over bulk ceria will serve as our example. Furthermore, the in situ Transmission Electron Microscopy is a powerful technique that can contribute to the study of atmosphere and temperature induced morphological or compositional changes of a catalyst at atomic resolution. The application of such techniques (PGAA and TEM) will pave the way to a greater and deeper understanding of the dynamic nature of active catalysts. Experimental/Methodology: In situ Prompt Gamma Activation Analysis (PGAA) experiments were carried out to determine the Cl uptake and the degree of surface chlorination under reaction conditions by varying p(O2), p(HCl), p(Cl2), and the reaction temperature. The abundance and dynamic evolution of OH groups on working catalyst under various steady-state conditions were studied by means of in situ FTIR with a specially designed homemade transmission cell. For real in situ TEM we use a commercial in situ holder with a home built gas feeding system and gas analytics. Conclusions: Two complimentary in situ techniques, namely in situ PGAA and in situ FTIR were utilities to investigate the surface coverage of the two most abundant species (Cl and OH). The OH density and Cl uptake were followed under multiple steady-state conditions as a function of p(O2), p(HCl), p(Cl2), and temperature. These experiments have shown that, the OH density positively correlates with the reactivity whereas Cl negatively. The p(HCl) experiments give rise to increased activity accompanied by Cl-coverage increase (opposite trend to p(O2) and T). Cl2 strongly inhibits the reaction, but no measurable increase of the Cl uptake was found. After considering all previous observations we conclude that only a minority of the available adsorption sites contribute to the reactivity. In addition, the mechanism of the catalysed reaction was proposed. The chlorine-oxygen competition for the available active sites renders re-oxidation as the rate-determining step of the catalysed reaction. Further investigations using in situ TEM are planned and will be conducted in the near future. Such experiments allow us to monitor active catalysts at the atomic scale under the most realistic conditions of temperature and pressure. The talk will shed a light on the potential and limitations of in situ PGAA and in situ TEM in the study of catalyst dynamics.

Keywords: CeO2, deacon process, in situ PGAA, in situ TEM, in situ FTIR

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3358 Calculation of A Sustainable Quota Harvesting of Long-tailed Macaque (Macaca fascicularis Raffles) in Their Natural Habitats

Authors: Yanto Santosa, Dede Aulia Rahman, Cory Wulan, Abdul Haris Mustari

Abstract:

The global demand for long-tailed macaques for medical experimentation has continued to increase. Fulfillment of Indonesian export demands has been mostly from natural habitats, based on a harvesting quota. This quota has been determined according to the total catch for a given year, and not based on consideration of any demographic parameters or physical environmental factors with regard to the animal; hence threatening the sustainability of the various populations. It is therefore necessary to formulate a method for calculating a sustainable harvesting quota, based on population parameters in natural habitats. Considering the possibility of variations in habitat characteristics and population parameters, a time series observation of demographic and physical/biotic parameters, in various habitats, was performed on 13 groups of long-tailed macaques, distributed throughout the West Java, Lampung and Yogyakarta areas of Indonesia. These provinces were selected for comparison of the influence of human/tourism activities. Data on population parameters that was collected included data on life expectancy according to age class, numbers of individuals by sex and age class, and ‘ratio of infants to reproductive females’. The estimation of population growth was based on a population dynamic growth model: the Leslie matrix. The harvesting quota was calculated as being the difference between the actual population size and the MVP (minimum viable population) for each sex and age class. Observation indicated that there were variations within group size (24 – 106 individuals), gender (sex) ratio (1:1 to 1:1.3), life expectancy value (0.30 to 0.93), and ‘ratio of infants to reproductive females’ (0.23 to 1.56). Results of subsequent calculations showed that sustainable harvesting quotas for each studied group of long-tailed macaques, ranged from 29 to 110 individuals. An estimation model of the MVP for each age class was formulated as Log Y = 0.315 + 0.884 Log Ni (number of individual on ith age class). This study also found that life expectancy for the juvenile age class was affected by the humidity under tree stands, and dietary plants’ density at sapling, pole and tree stages (equation: Y= 2.296 – 1.535 RH + 0.002 Kpcg – 0.002 Ktg – 0.001 Kphn, R2 = 89.6% with a significance value of 0.001). By contrast, for the sub-adult-adult age class, life expectancy was significantly affected by slope (equation: Y=0.377 = 0.012 Kml, R2 = 50.4%, with significance level of 0.007). The infant to reproductive female ratio was affected by humidity under tree stands, and dietary plant density at sapling and pole stages (equation: Y = -1.432 + 2.172 RH – 0.004 Kpcg + 0.003 Ktg, R2 = 82.0% with significance level of 0.001). This research confirmed the importance of population parameters in determining the minimum viable population, and that MVP varied according to habitat characteristics (especially food availability). It would be difficult therefore, to formulate a general mathematical equation model for determining a harvesting quota for the species as a whole.

Keywords: harvesting, long-tailed macaque, population, quota

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3357 High Temperature Behaviour of Various Limestone Used in Heritage Buildings at Material and Block Scales

Authors: Ayoub Daoudi, Javad Eslami, Anne-Lise Beaucour, Martin Vigroux, Albert Noumowé

Abstract:

As a fact, many cultural heritage masonry buildings have undergone violent fires during their history. In order to investigate the high temperature behaviour of stone masonry, six French limestones were heated to 600 °C at a rate of 9 °C/min. The main focus is the comparison between the high temperature behaviour of stones at the material and at the structural scale. In order to evaluate the risk of spalling, the tests have been carried out on the stone blocks (12x30x30 cm) instrumented with thermocouples and subjected to an unidirectional heating on one face. Thereafter, visual assessments and non-destructive measurements (dynamic elastic modulus) performed on blocks demonstrate a different behaviour from what was observed at the material scale. Finally, a series of thermo-mechanical computations, using finite element method, allowed us to highlight the difference between the behaviour of stones at material and block scales.

Keywords: limestones, hight temperature behaviour, damage, thermo-mechanical modeling, material and blocks scales, color change

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3356 Experimental Study of Sahara Climat Effect in Photovoltaic Solar Module

Authors: A. Benatiallah, A. Hadjadj, D. Benatiallah, F. Abaidi, A. Harrouz

Abstract:

Photovoltaic system is established as a reliable and economical source of electricity in rural and Sahara areas, especially in developing countries where the population is dispersed, has low consumption of energy and the grid power is not extended to these areas due to viability and financial problems. The production of energy by the photovoltaic system is very fluctuates and depend of meteorological conditions. Wind is a very important and often neglected parameter in the behavior of the solar module. The electric performances of a solar module to the silicon are very appreciable to the blows; in the present work we have studies the behavior of multi-crystal solar module according to the density of dust, and the principals electric feature of the solar module. An evaluation permits to affirm that a solar module under the effect of sand will collect a lower flux to the normal conditions.

Keywords: photovoltaic, multi-crystal module, experimental, effect of dust, performances

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3355 Mutual Information Based Image Registration of Satellite Images Using PSO-GA Hybrid Algorithm

Authors: Dipti Patra, Guguloth Uma, Smita Pradhan

Abstract:

Registration is a fundamental task in image processing. It is used to transform different sets of data into one coordinate system, where data are acquired from different times, different viewing angles, and/or different sensors. The registration geometrically aligns two images (the reference and target images). Registration techniques are used in satellite images and it is important in order to be able to compare or integrate the data obtained from these different measurements. In this work, mutual information is considered as a similarity metric for registration of satellite images. The transformation is assumed to be a rigid transformation. An attempt has been made here to optimize the transformation function. The proposed image registration technique hybrid PSO-GA incorporates the notion of Particle Swarm Optimization and Genetic Algorithm and is used for finding the best optimum values of transformation parameters. The performance comparision obtained with the experiments on satellite images found that the proposed hybrid PSO-GA algorithm outperforms the other algorithms in terms of mutual information and registration accuracy.

Keywords: image registration, genetic algorithm, particle swarm optimization, hybrid PSO-GA algorithm and mutual information

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3354 An Assessment of Wind Energy in Sanar Village in North of Iran Using Weibull Function

Authors: Ehsanolah Assareh, Mojtaba Biglari, Mojtaba Nedaei

Abstract:

Sanar village in north of Iran is a remote region with difficult access to electricity, grid and water supply. Thus the aim of this research is to evaluate the potential of wind as a power source either for electricity generation or for water pumping. In this study the statistical analysis has been performed by Weibull distribution function. The results show that the Weibull distribution has fitted the wind data very well. Also it has been demonstrated that wind speed at 40 m height is ranged from 1.75 m/s in Dec to 3.28 m/s in Aug with average value of 2.69 m/s. In this research, different wind speed characteristics such as turbulence intensity, wind direction, monthly air temperature, humidity wind power density and other related parameters have been investigated. Finally it was concluded that the wind energy in the Sanar village may be explored by employing modern wind turbines that require very lower start-up speeds.

Keywords: wind energy, wind turbine, weibull, Sanar village, Iran

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3353 Vibration Measurements of Single-Lap Cantilevered SPR Beams

Authors: Xiaocong He

Abstract:

Self-pierce riveting (SPR) is a new high-speed mechanical fastening technique which is suitable for point joining dissimilar sheet materials, as well as coated and pre-painted sheet materials. Mechanical structures assembled by SPR are expected to possess a high damping capacity. In this study, experimental measurement techniques were proposed for the prediction of vibration behavior of single-lap cantilevered SPR beams. The dynamic test software and the data acquisition hardware were used in the experimental measurement of the dynamic response of the single-lap cantilevered SPR beams. Free and forced vibration behavior of the single-lap cantilevered SPR beams was measured using the LMS CADA-X experimental modal analysis software and the LMS-DIFA Scadas II data acquisition hardware. The frequency response functions of the SPR beams of different rivet number were compared. The main goal of the paper is to provide a basic measuring method for further research on vibration based non-destructive damage detection in single-lap cantilevered SPR beams.

Keywords: self-piercing riveting, dynamic response, experimental measurement, frequency response functions

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3352 Observer-Based Control Design for Double Integrators Systems with Long Sampling Periods and Actuator Uncertainty

Authors: Tomas Menard

Abstract:

The design of control-law for engineering systems has been investigated for many decades. While many results are concerned with continuous systems with continuous output, nowadays, many controlled systems have to transmit their output measurements through network, hence making it discrete-time. But it is well known that the sampling of a system whose control-law is based on the continuous output may render the system unstable, especially when this sampling period is long compared to the system dynamics. The control design then has to be adapted in order to cope with this issue. In this paper, we consider systems which can be modeled as double integrator with uncertainty on the input since many mechanical systems can be put under such form. We present a control scheme based on an observer using only discrete time measurement and which provides continuous time estimation of the state, combined with a continuous control law, which stabilized a system with second-order dynamics even in the presence of uncertainty. It is further shown that arbitrarily long sampling periods can be dealt with properly setting the control scheme parameters.

Keywords: dynamical system, control law design, sampled output, observer design

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3351 Effect of T6 and Re-Aging Heat Treatment on Mechanical Properties of 7055 Aluminum Alloy

Authors: M. Esmailian, M. Shakouri, A. Mottahedi, S. G. Shabestari

Abstract:

Heat treatable aluminium alloys such as 7075 and 7055, because of high strength and low density, are used widely in aircraft industry. For best mechanical properties, T6 heat treatment has recommended for this regards, but this temper treatment is sensitive to corrosion induced and Stress Corrosion Cracking (SCC) damage. For improving this property, the over-aging treatment (T7) applies to this alloy, but it decreases the mechanical properties up to 30 percent. Hence, to increase the mechanical properties, without any remarkable decrease in SCC resistant, Retrogression and Re-Aging (RRA) heat treatment is used. This treatment performs in a relatively short time. In this paper, the RRA heat treatment was applied to 7055 aluminum alloy and then effect of RRA time on the mechanical properties of 7055 has been investigated. The results show that the 40 minute time is suitable time for retrogression of 7055 aluminum alloy and ultimate strength increases up to 625MPa.

Keywords: 7055 Aluminum alloy, mechanical properties, SCC resistance, heat Treatment

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3350 Probability of Passing the Brake Test at Ministry of Transport Facilities of Each City at Alicante Region from Spain

Authors: Carolina Senabre Blanes, Sergio Valero Verdú, Emilio Velasco SáNchez

Abstract:

This research objective is to obtain a percentage of success for each Ministry of Transport (MOT) facilities of each city of the Alicante region from Comunidad Valenciana from Spain by comparing results obtained by using different brake testers. It has been studied which types of brake tester are being used at each city nowadays. Different types of brake testers are used at each city, and the mechanical engineering staffs from the Miguel Hernández University have studied differences between all of them, and have obtained measures from each type. A percentage of probability of success will be given to each MOT station when you try to pass the exam with the same car with same characteristics and the same wheels. In other words, parameters of the vehicle have been controlled to be the same at all tests; therefore, brake measurements variability will be due to the type of testers could be used at the MOT station. A percentage of probability to pass the brake exam at each city will be given by comparing results of tests.

Keywords: brake tester, Mot station, probability to pass the exam, brake tester characteristics

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3349 Depyritization of US Coal Using Iron-Oxidizing Bacteria: Batch Stirred Reactor Study

Authors: Ashish Pathak, Dong-Jin Kim, Haragobinda Srichandan, Byoung-Gon Kim

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Microbial depyritization of coal using chemoautotrophic bacteria is gaining acceptance as an efficient and eco-friendly technique. The process uses the metabolic activity of chemoautotrophic bacteria in removing sulfur and pyrite from the coal. The aim of the present study was to investigate the potential of Acidithiobacillus ferrooxidans in removing the pyritic sulfur and iron from high iron and sulfur containing US coal. The experiment was undertaken in 8 L bench scale stirred tank reactor having 1% (w/v) pulp density of coal. The reactor was operated at 35ºC and aerobic conditions were maintained by sparging the air into the reactor. It was found that at the end of bio-depyritization process, about 90% of pyrite and 67% of pyritic sulfur was removed from the coal. The results indicate that the bio-depyritization process is an efficient process in treating the high pyrite and sulfur containing coal.

Keywords: At.ferrooxidans, batch reactor, coal desulfurization, pyrite

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3348 Behavior of hFOB 1.19 Cells in Injectable Scaffold Composing of Pluronic F127 and Carboxymethyl Hexanoyl Chitosan

Authors: Lie-Sian Yap, Ming-Chien Yang

Abstract:

This study demonstrated a novel injectable hydrogel scaffold composing of Pluronic F127, carboxymethyl hexanoyl chitosan (CA) and glutaraldehyde (GA) for encapsulating human fetal osteoblastic cells (hFOB) 1.19. The hydrogel was prepared by mixing F127 and GA in CA solution at 4°C. The mechanical properties and cytotoxicity of this hydrogel were determined through rheological measurements and MTT assay, respectively. After encapsulation process, the hFOB 1.19 cells morphology was examined using fluorescent and confocal imaging. The results indicated that the Tgel of this system was around 30°C, where sol-gel transformation occurred within 90s and F127/CA/GA gel was able to remain intact in the medium for more than 1 month. In vitro cell culture assay revealed that F127/CA/GA hydrogels were non-cytotoxic. Encapsulated hFOB 1.19 cells not only showed the spherical shape and formed colonies, but also reduced their size. Moreover, the hFOB 1.19 cells showed that cells remain alive after the encapsulation process. Based on these results, these F127/CA/GA hydrogels can be used to encapsulate cells for tissue engineering applications.

Keywords: carboxymethyl hexanoyl chitosan, cell encapsulation, hFOB 1.19, Pluronic F127

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3347 Computational Study of Passive Scalar Diffusion of a Counterflowing round Jet

Authors: Amani Amamou, Sabra Habli, Nejla Mahjoub Saïd, Georges Le Palec

Abstract:

Round jets have been widely studied due to their important application in industry. Many configurations of round jet were encountered in literature as free jet, co-flow jet, couterflowing jet and cross flow jet. In this paper, we are concerned with turbulent round jet in uniform counterflow stream which is known to enhance mixing and dispersion efficiency owing to flow reversal. This type of flow configuration is a typical application in environmental engineering such as the disposal of wastewater into seas or rivers. A computational study of a turbulent circular jet discharging into a uniform counterflow is conducted in order to investigate the characteristics of the diffusion field of the jet effluent. The investigation is carried out for three different cases of jet-to-current velocity ratios; low, medium and high velocity ratios. The Reynolds Stress Model (RSM) is used in the comparison with available experimental measurements. The decay of the center line velocity and the dynamic proprieties of the flow together with the centerline dilution of the passive scalar and the other characteristics of the concentration field are computationally analyzed in this paper.

Keywords: Counterflow stream, jet, velocity, concentration

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3346 Development of Adhesive from Prosopis african Seed Endosperm (OKPEYI)

Authors: Florence Chinyere Nwangwu, Rosemary Ene

Abstract:

An experimental study was carried out to develop an adhesive from Prosopis africana seed endosperm. The Prosopis seeds for this work were obtained from Enugu State in the South East part of Nigeria. The Prosopis seeds were prepared by separating the Prosopis endosperm from the seed coat and cotyledon. The dry adhesive gotten from the endosperm was later dissolved to get the adhesive solution. Confirmatory tests like viscosity, density, pH, and binding strength were carried out. The effect of time, temperature, concentration on the yield and properties of the adhesive were investigated. The results obtained showed that increase in concentration, time, temperature decreases the viscosity of the Prosopis adhesive and yield of Prosopis endosperm. It was also deduced that increase in viscosity increases the binding strength of the Prosopis adhesive. The percentage of the adhesive yield from Prosopis endosperm showed that the commercialization of the seed in Nigeria will be possible and profitable.

Keywords: adhesive, Prosopis, viscosity, endosperm

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3345 Language Anxiety and Motivation as Predictors of English as a Foreign Language Achievement

Authors: Fakieh Alrabai

Abstract:

The present study examines the predictive power of foreign language anxiety and motivation, as two significant affective variables, in English as a foreign language (EFL) achievement. It also explores the causal relationship between these two factors (i.e. which variable causes the other); and which one of them best predicts other affective factors including learner attitude, self-esteem, and autonomy. The study utilized experimental treatments among 210 Saudi EFL learners divided into four groups. Group 1 was exposed to anxiety-controlling moments, group 2 was exposed to motivational moments, group 3 was exposed to anxiety-controlling and motivational moments together, and group 4 was exposed to no specific anxiety or motivation strategies. The influence of the treatment on the study variables was evaluated using a triangulation of measurements including questionnaires, classroom observations, and achievement tests. Descriptive analysis, ANOVA, ANCOVA, and regression analyses have been deployed to figure out the study findings. While both motivation and anxiety significantly predicted learners EFL achievement, motivation has been found to be the best predictor of learners’ achievement; and therefore, operates as the mediator of EFL achievement.

Keywords: motivation, anxiety, achievement, autonomy

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3344 Mineral Thermal Insulation Materials Based on Sodium Liquid Glass

Authors: Zin Min Htet, Tikhomirova Irina Nikolaevna, Karpenko Marina A.

Abstract:

In this paper, thermal insulation materials based on sodium liquid glass with light fillers as foam glass granules with different sizes and wollastonite - M325 (U.S.A production) were studied. Effective mineral thermal insulation materials are in demand in many industries because of their incombustibility and durability. A method for the preparation of such materials based on mechanically foamed sodium liquid glass and light mineral fillers is proposed. The thermal insulation properties depend on the type, amount of filler and on the foaming factor, which is determined by the concentration of the foaming agent. The water resistance of the material is provided by using an additive to neutralize the glass and transfer it to the silica gel.

Keywords: thermal insulation material, sodium liquid glass, foam glass granules, foaming agent, hardener, thermal conductivity, apparent density, compressive strength

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3343 GaAs Based Solar Cells: Growth, Fabrication, and Characterization

Authors: Hülya Kuru Mutlu, Mustafa Kulakcı, Uğur Serincan

Abstract:

The sun is one of the latest developments in renewable energy sources, which has a variety of application. Solar energy is the most preferred renewable energy sources because it can be used directly, it protects the environment and it is economic. In this work, we investigated that important parameter of GaAs-based solar cells with respect to the growth temperature. The samples were grown on (100) oriented p-GaAs substrates by solid source Veeco GEN20MC MBE system equipped with Ga, In, Al, Si, Be effusion cells and an Arsenic cracker cell. The structures of the grown samples are presented. After initial oxide desorption, Sample 1 and Sample 2 were grown at about 585°C and 535°C, respectively. From the grown structures, devices were fabricated by using the standard photolithography procedure. Current-voltage measurements were performed at room temperature (RT). It is observed that Sample 1 which was grown at 585°C has higher efficiency and fill factor compared to Sample 2. Hence, it is concluded that the growth temperature of 585°C is more suitable to grow GaAs-based solar cells considering our samples used in this study.

Keywords: molecular beam epitaxy, solar cell, current-voltage measurement, Sun

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3342 Automatic Identification and Classification of Contaminated Biodegradable Plastics using Machine Learning Algorithms and Hyperspectral Imaging Technology

Authors: Nutcha Taneepanichskul, Helen C. Hailes, Mark Miodownik

Abstract:

Plastic waste has emerged as a critical global environmental challenge, primarily driven by the prevalent use of conventional plastics derived from petrochemical refining and manufacturing processes in modern packaging. While these plastics serve vital functions, their persistence in the environment post-disposal poses significant threats to ecosystems. Addressing this issue necessitates approaches, one of which involves the development of biodegradable plastics designed to degrade under controlled conditions, such as industrial composting facilities. It is imperative to note that compostable plastics are engineered for degradation within specific environments and are not suited for uncontrolled settings, including natural landscapes and aquatic ecosystems. The full benefits of compostable packaging are realized when subjected to industrial composting, preventing environmental contamination and waste stream pollution. Therefore, effective sorting technologies are essential to enhance composting rates for these materials and diminish the risk of contaminating recycling streams. In this study, it leverage hyperspectral imaging technology (HSI) coupled with advanced machine learning algorithms to accurately identify various types of plastics, encompassing conventional variants like Polyethylene terephthalate (PET), Polypropylene (PP), Low density polyethylene (LDPE), High density polyethylene (HDPE) and biodegradable alternatives such as Polybutylene adipate terephthalate (PBAT), Polylactic acid (PLA), and Polyhydroxyalkanoates (PHA). The dataset is partitioned into three subsets: a training dataset comprising uncontaminated conventional and biodegradable plastics, a validation dataset encompassing contaminated plastics of both types, and a testing dataset featuring real-world packaging items in both pristine and contaminated states. Five distinct machine learning algorithms, namely Partial Least Squares Discriminant Analysis (PLS-DA), Support Vector Machine (SVM), Convolutional Neural Network (CNN), Logistic Regression, and Decision Tree Algorithm, were developed and evaluated for their classification performance. Remarkably, the Logistic Regression and CNN model exhibited the most promising outcomes, achieving a perfect accuracy rate of 100% for the training and validation datasets. Notably, the testing dataset yielded an accuracy exceeding 80%. The successful implementation of this sorting technology within recycling and composting facilities holds the potential to significantly elevate recycling and composting rates. As a result, the envisioned circular economy for plastics can be established, thereby offering a viable solution to mitigate plastic pollution.

Keywords: biodegradable plastics, sorting technology, hyperspectral imaging technology, machine learning algorithms

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3341 A DOE Study of Ultrasound Intensified Removal of Phenol

Authors: P. R. Rahul, A. Kannan

Abstract:

Ultrasound-aided adsorption of phenol by Granular Activated Carbon (GAC) was investigated at different frequencies ranging from 35 kHz, 58 kHz, and 192 kHz. Other factors influencing adsorption such as Adsorbent dosage (g/L), the initial concentration of the phenol solution (ppm) and RPM was also considered along with the frequency variable. However, this study involved calorimetric measurements which helped is determining the effect of frequency on the % removal of phenol from the power dissipated to the system was normalized. It was found that low frequency (35 kHz) cavitation effects had a profound influence on the % removal of phenol per unit power. This study also had cavitation mapping of the ultrasonic baths, and it showed that the effect of cavitation on the adsorption system is irrespective of the position of the vessel. Hence, the vessel was placed at the center of the bath. In this study, novel temperature control and monitoring system to make sure that the system is under proper condition while operations. From the BET studies, it was found that there was only 5% increase in the surface area and hence it was concluded that ultrasound doesn’t profoundly alter the equilibrium value of the adsorption system. DOE studies indicated that adsorbent dosage has a higher influence on the % removal in comparison with other factors.

Keywords: ultrasound, adsorption, granulated activated carbon, phenol

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3340 A Combinatorial Representation for the Invariant Measure of Diffusion Processes on Metric Graphs

Authors: Michele Aleandri, Matteo Colangeli, Davide Gabrielli

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We study a generalization to a continuous setting of the classical Markov chain tree theorem. In particular, we consider an irreducible diffusion process on a metric graph. The unique invariant measure has an atomic component on the vertices and an absolutely continuous part on the edges. We show that the corresponding density at x can be represented by a normalized superposition of the weights associated to metric arborescences oriented toward the point x. A metric arborescence is a metric tree oriented towards its root. The weight of each oriented metric arborescence is obtained by the product of the exponential of integrals of the form ∫a/b², where b is the drift and σ² is the diffusion coefficient, along the oriented edges, for a weight for each node determined by the local orientation of the arborescence around the node and for the inverse of the diffusion coefficient at x. The metric arborescences are obtained by cutting the original metric graph along some edges.

Keywords: diffusion processes, metric graphs, invariant measure, reversibility

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3339 Reduce of the Consumption of Industrial Kilns a Pottery Kiln as Example, Recovery of Lost Energy Using a System of Heat Exchangers and Modeling of Heat Transfer Through the Walls of the Kiln

Authors: Maha Bakkari, Fatiha Lemmeni, Rachid Tadili

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In this work, we present some characteristics of the furnace studied, its operating principle and the experimental measurements of the evolutions of the temperatures inside and outside the walls of the This work deals with the problem of energy consumption of pottery kilns whose energy consumption is relatively too high. In this work, we determined the sources of energy loss by studying the heat transfer of a pottery furnace, we proposed a recovery system to reduce energy consumption, and then we developed a numerical model modeling the transfers through the walls of the furnace and to optimize the insulation (reduce heat losses) by testing multiple insulators. The recovery and reuse of energy recovered by the recovery system will present a significant gain in energy consumption of the oven and cooking time. This research is one of the solutions that helps reduce the greenhouse effect of the planet earth, a problem that worries the world.

Keywords: recovery lost energy, energy efficiency, modeling, heat transfer

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3338 Non-Singular Gravitational Collapse of a Dust Cloud in Einstein-Cartan Theory

Authors: Amir Hadi Ziaie, Mostafa Hashemi, Shahram Jalalzadeh

Abstract:

It is now known that the end state of the collapse process of a dense star under its own gravity is the formation of a spacetime singularity. This is the spacetime event where the energy density and spacetime curvature diverge, and the classical general relativity breaks down. As we know, a realistic star is composed of fermions so that their spin effects could alter the final fate of the collapse scenario. The underlying theory within which the inclusion of spin effects can be worked out is the Einstein-Cartan theory. In this theory, the spacetime torsion which is defined as a geometrical quantity, is related to an intrinsic angular momentum of fermions (spin). In this work, we study the collapse process of a homogeneous spin fluid in such a framework and show that taking into account the spin effects of the collapsing cloud could prevent the formation of spacetime singularity.

Keywords: gravitational collapse, einstein-cartan theory, spacetime singularity, black hole physics

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3337 Experimental Measurements for the Effect of Dilution Procedure in Blood Esterases as Animals Biomarker for Exposure to Organophosphate Compounds

Authors: Kasim Sakran Abass

Abstract:

This main aim of this study was to confirm and extend our current knowledge about the effects of dilutions on esterases activities in the blood for birds with respect to protecting the enzyme from organophosphate inhibition. There were significantly higher esterases activities in dilution 1:10 in all blood samples from quail, duck, and chick compared to other dilutions (1:5, 1:15, 1:20, and 1:25). Furthermore, our results also pointed to the importance of estimating different dilutions effects prior to using in birds as biomarker tools of environmental exposure. Concentration–inhibition curves were determined for the inhibitor in the presence of dilutions 1:5, 1:10 plus 1:15 (to stimulate carboxylesterase). Point estimates (concentrations calculated to produce 20, 50, and 80% inhibition) were compared across conditions and served as a measure of esterase-mediated detoxification. Among the thiol esters (dilution 1:5) was observed to have the highest specificity constant (kcat/Km), and the Km and kcat values were 176 μM and 16,765 s−1, respectively for S-phenyl thioacetate ester, while detected in (dilution 1:15) the lowest specificity constant (kcat/Km), and the Km and kcat values were 943 μM and 1154 s−1, respectively for acetylthiocholine iodide ester.

Keywords: esterase, animal, dilution, pesticides

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3336 Modelling of Lunar Lander’s Thruster’s Exhaust Plume Impingement in Vacuum

Authors: Mrigank Sahai, R. Sri Raghu

Abstract:

This paper presents the modelling of rocket exhaust plume flow field and exhaust plume impingement in vacuum for the liquid apogee engine and attitude control thrusters of the lunar lander. Analytic formulations for rarefied gas kinetics has been taken as reference for modelling the plume flow field. The plume has been modelled as high speed, collision-less, axi-symmetric gas jet, expanding into vacuum and impinging at a normally set diffusive circular plate. Specular reflections have not been considered for the present study. Different parameters such as number density, temperature, pressure, flow velocity, heat flux etc., have been calculated and have been plotted against and compared to Direct Simulation Monte Carlo results. These analyses have provided important information for the placement of critical optical instruments and design of optimal thermal insulation for the hardware that may come in contact with the thruster exhaust.

Keywords: collision-less gas, lunar lander, plume impingement, rarefied exhaust plume

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3335 PM10 Prediction and Forecasting Using CART: A Case Study for Pleven, Bulgaria

Authors: Snezhana G. Gocheva-Ilieva, Maya P. Stoimenova

Abstract:

Ambient air pollution with fine particulate matter (PM10) is a systematic permanent problem in many countries around the world. The accumulation of a large number of measurements of both the PM10 concentrations and the accompanying atmospheric factors allow for their statistical modeling to detect dependencies and forecast future pollution. This study applies the classification and regression trees (CART) method for building and analyzing PM10 models. In the empirical study, average daily air data for the city of Pleven, Bulgaria for a period of 5 years are used. Predictors in the models are seven meteorological variables, time variables, as well as lagged PM10 variables and some lagged meteorological variables, delayed by 1 or 2 days with respect to the initial time series, respectively. The degree of influence of the predictors in the models is determined. The selected best CART models are used to forecast future PM10 concentrations for two days ahead after the last date in the modeling procedure and show very accurate results.

Keywords: cross-validation, decision tree, lagged variables, short-term forecasting

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3334 A Statistical Model for the Dynamics of Single Cathode Spot in Vacuum Cylindrical Cathode

Authors: Po-Wen Chen, Jin-Yu Wu, Md. Manirul Ali, Yang Peng, Chen-Te Chang, Der-Jun Jan

Abstract:

Dynamics of cathode spot has become a major part of vacuum arc discharge with its high academic interest and wide application potential. In this article, using a three-dimensional statistical model, we simulate the distribution of the ignition probability of a new cathode spot occurring in different magnetic pressure on old cathode spot surface and at different arcing time. This model for the ignition probability of a new cathode spot was proposed in two typical situations, one by the pure isotropic random walk in the absence of an external magnetic field, other by the retrograde motion in external magnetic field, in parallel with the cathode surface. We mainly focus on developed relationship between the ignition probability density distribution of a new cathode spot and the external magnetic field.

Keywords: cathode spot, vacuum arc discharge, transverse magnetic field, random walk

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3333 Tall Building Transit-Oriented Development (TB-TOD) and Energy Efficiency in Suburbia: Case Studies, Sydney, Toronto, and Washington D.C.

Authors: Narjes Abbasabadi

Abstract:

As the world continues to urbanize and suburbanize, where suburbanization associated with mass sprawl has been the dominant form of this expansion, sustainable development challenges will be more concerned. Sprawling, characterized by low density and automobile dependency, presents significant environmental issues regarding energy consumption and Co2 emissions. This paper examines the vertical expansion of suburbs integrated into mass transit nodes as a planning strategy for boosting density, intensification of land use, conversion of single family homes to multifamily dwellings or mixed use buildings and development of viable alternative transportation choices. It analyzes the spatial patterns of tall building transit-oriented development (TB-TOD) of suburban regions in Sydney (Australia), Toronto (Canada), and Washington D.C. (United States). The main objectives of this research seek to understand the effect of the new morphology of suburban tall, the physical dimensions of individual buildings and their arrangement at a larger scale with energy efficiency. This study aims to answer these questions: 1) why and how can the potential phenomenon of vertical expansion or high-rise development be integrated into suburb settings? 2) How can this phenomenon contribute to an overall denser development of suburbs? 3) Which spatial pattern or typologies/ sub-typologies of the TB-TOD model do have the greatest energy efficiency? It addresses these questions by focusing on 1) energy, heat energy demand (excluding cooling and lighting) related to design issues at two levels: macro, urban scale and micro, individual buildings—physical dimension, height, morphology, spatial pattern of tall buildings and their relationship with each other and transport infrastructure; 2) Examining TB-TOD to provide more evidence of how the model works regarding ridership. The findings of the research show that the TB-TOD model can be identified as the most appropriate spatial patterns of tall buildings in suburban settings. And among the TB-TOD typologies/ sub-typologies, compact tall building blocks can be the most energy efficient one. This model is associated with much lower energy demands in buildings at the neighborhood level as well as lower transport needs in an urban scale while detached suburban high rise or low rise suburban housing will have the lowest energy efficiency. The research methodology is based on quantitative study through applying the available literature and static data as well as mapping and visual documentations of urban regions such as Google Earth, Microsoft Bing Bird View and Streetview. It will examine each suburb within each city through the satellite imagery and explore the typologies/ sub-typologies which are morphologically distinct. The study quantifies heat energy efficiency of different spatial patterns through simulation via GIS software.

Keywords: energy efficiency, spatial pattern, suburb, tall building transit-oriented development (TB-TOD)

Procedia PDF Downloads 252