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2018

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Toxoplasma Gondii And Substance Use - Project Data, Andrew Berrett Jan 2018

Toxoplasma Gondii And Substance Use - Project Data, Andrew Berrett

ScholarsArchive Data

The data utilized in this project originated from the Centers for Disease Control and Prevention's National Health and Nutrition Examination Survey (NHANES) data sets. Specifically, we utilized data from the NHANES III and 2009-2014 continuous NHANES data sets. Data files pertinent to our project were downloaded from the NHANES website (NHANES.com) and merged into two master data files, one for the NHANES III and one for the continuous NHANES. Following the merges, some variables were modified or recoded for the purposes of the project. Therefore, the data files associated with this entry include both the original NHANES data as well …

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Youtube Ted Talk Comment Sentiment Data, Royce Kimmons Jan 2018

Youtube Ted Talk Comment Sentiment Data, Royce Kimmons

ScholarsArchive Data

This dataset includes comments to all available TED Talk videos on YouTube. Videos are coded for presenter gender and format, and comments are coded for sentiment using SentiStrength.

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A Novel Multistage System For The Detection And Removal Of Pectoral Muscles Inmammograms, İdi̇l Işikli Esener, Semi̇h Ergi̇n, Tolga Yüksel Jan 2018

A Novel Multistage System For The Detection And Removal Of Pectoral Muscles Inmammograms, İdi̇l Işikli Esener, Semi̇h Ergi̇n, Tolga Yüksel

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel multistage scheme for pectoral muscle removal from mammography images is proposed, and the performance of this system is verified using the publicly available Mammographic Image Analysis Society digital mammogram database. This database is composed of mediolateral oblique mammography images including three different tissue types (fatty, fatty-glandular, and dense-glandular) with three health status types (normal, benign cancer, and malignant cancer). In the implementation of the proposed system, a mammography image is first preprocessed by performing noise reduction background removal followed by artifact suppression processes. Then a presegmentation procedure is applied using region growing and line fitting …

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A New Semianalytical Method For Analysis Of The Disc-Type Permanent Magnethysteresis Motor In Steady-State Operational Conditions, Ali Behniafar, Ahmad Darabi Jan 2018

A New Semianalytical Method For Analysis Of The Disc-Type Permanent Magnethysteresis Motor In Steady-State Operational Conditions, Ali Behniafar, Ahmad Darabi

Turkish Journal of Electrical Engineering and Computer Sciences

Considering the characteristics of hysteresis and permanent magnet motors, it seems that these two motors are complements of each other. Thus, their combination yields a motor with an excellent performance. In order to preserve the major advantages of both motors in the new motor, a disc-type slotless structure is chosen. This paper presents a new finite-element method for the modeling of disc-type permanent magnet hysteresis synchronous (PMHS) motor. In this modeling method a new iterative algorithm is used. Programming software has been linked to finite- element software because of its limitation in the modeling of hysteresis phenomena. Validity of the …

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Classification Of Surface Electromyogram Signals Based On Directed Acyclic Graphs And Support Vector Machines, Xinhui Hu, Jiangming Kan, Wenbin Li Jan 2018

Classification Of Surface Electromyogram Signals Based On Directed Acyclic Graphs And Support Vector Machines, Xinhui Hu, Jiangming Kan, Wenbin Li

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a novel classification approach for surface electromyogram (sEMG) signals. The proposed classification approach involves two steps: (1) feature extraction from an sEMG, in which a 7-dimensional feature vector is extracted from 27 types of features of the sEMG by linear discriminant analysis (LDA), and (2) a novel classifier, DAGSVMerr, based on a directed acyclic graph (DAG) and support vector machine (SVM), in which a separability measure function based on erroneous recognition rates (ERRs) is defined to determine the initial operation list. The proposed approach takes advantage of the feedback idea to improve the performance of the classification. …

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Nonlinear Analysis Of Hybrid Phase-Controlled Systems In Z-Domain With Convex Lmi Searches, Nur Syazreen Ahmad, Pei Ni Goh Jan 2018

Nonlinear Analysis Of Hybrid Phase-Controlled Systems In Z-Domain With Convex Lmi Searches, Nur Syazreen Ahmad, Pei Ni Goh

Turkish Journal of Electrical Engineering and Computer Sciences

Phase-controlled systems such as phase-locked loops (PLLs) have been used in numerous applications ranging from data communications to speed motor control. The hybrid case where only the phase detector is digital while others are analog has advantages over the classical PLLs in the sense that it provides a wider locking range and is more suitable when the input and output signals come in digital waveforms. Although such systems are inherently nonlinear due to the phase detector's characteristics, the nonlinearity is often bypassed in order to ease the analysis and design methods. This, however, will give erroneous results when the phase …

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Modeling Of Realistic Heart Electrical Excitation Based On Dti Scans And Modified Reaction Diffusion Equation, Ihab Elaff Jan 2018

Modeling Of Realistic Heart Electrical Excitation Based On Dti Scans And Modified Reaction Diffusion Equation, Ihab Elaff

Turkish Journal of Electrical Engineering and Computer Sciences

A new method is proposed for modeling realistic heart activation using diffusion tensor imaging (DTI) scans based on biological properties of its tissues in addition to the working methodology of the DTI scanner. Modeling of the excitation propagation inside the heart is initiated by applying activation at only one pacing site at the root of the conduction network. The excitation propagation has been accomplished based on a proposed conduction system that is extracted from DTI heart scans and a modified version of monodomain reaction diffusion equation (RDE) that considers the heart inhomogeneous--anisotropic material. The Aliev--Panfilov method was used to model …

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The Application Of Analytical Mechanics In A Multimachine Power System, Zhijie Wang, Zhiyuan Liu, Jie Wang, Xiuchen Jiang, Sanming Liu, Yifang Liu, Gehao Sheng, Tianyu Liu Jan 2018

The Application Of Analytical Mechanics In A Multimachine Power System, Zhijie Wang, Zhiyuan Liu, Jie Wang, Xiuchen Jiang, Sanming Liu, Yifang Liu, Gehao Sheng, Tianyu Liu

Turkish Journal of Electrical Engineering and Computer Sciences

Analytical mechanics methods play an important role in determining the energy function and Hamilton realization of a system. In this paper, the Hamilton function of the system is obtained directly from the system differential equation by means of analytical mechanics. In addition, the system Hamiltonization process requires that the system must be even order, and the commonly used generator model is a single-axis third-order model. For this reason, the odd-order power system model is extended to an even-order system. The Hamilton function of the system is deduced with coordinate transformation and the generalized force. Then the standard form of Hamilton …

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Simulation Of Infinite Periodic Graphene Planar Grating In The Thz Range By The Method Of Singular Integral Equations, Mstislav Kaliberda, Leonid Lytvynenko, Sergey Pogarsky Jan 2018

Simulation Of Infinite Periodic Graphene Planar Grating In The Thz Range By The Method Of Singular Integral Equations, Mstislav Kaliberda, Leonid Lytvynenko, Sergey Pogarsky

Turkish Journal of Electrical Engineering and Computer Sciences

Plane wave diffraction by the infinite periodic planar graphene grating and infinite grating above a perfectly conducting plane in the THz range is considered. The mathematical model is based on the graphene surface impedance and the method of singular integral equations. A comparison with finite grating is made. Reflectance, transmittance, and absorbance are studied as a function of graphene and grating parameters.

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Improved Method Of Heuristic Classification Of Vowels From An Acoustic Signal, Josef Krocil, Zdenek Machacek, Jiri Koziorek, Radek Martinek, Jan Nedoma, Marcel Fajkus Jan 2018

Improved Method Of Heuristic Classification Of Vowels From An Acoustic Signal, Josef Krocil, Zdenek Machacek, Jiri Koziorek, Radek Martinek, Jan Nedoma, Marcel Fajkus

Turkish Journal of Electrical Engineering and Computer Sciences

This paper describes research in the field of the improved methodology of the classification of vowels /a, a:/, /$\varepsilon$, $\varepsilon$:/, /ı, i:/, /o, o:/, and /u, u:/ (vowel symbols according to IPA, i.e. International Phonetic Alphabet). The aim is to develop an improved method enabling the automatic allocation of vowel symbols to the corresponding time segments of acoustic recordings of an undisturbed speech signal. The combined classification method is based on finding frequencies of the first two local maxims (formants) in a smoothed linear predictive amplitude spectrum (LPC, linear predictive coding) and zero-crossing values of each speech active voiced short-term …

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Effect Of Cu Modified Tio2 Catalysts Prepared By Incipient Wetness Impregnation And Sputtering For Photocatalytic Co2 Reduction In Aqueous Solution, Nantiya Jantarasorn Jan 2018

Effect Of Cu Modified Tio2 Catalysts Prepared By Incipient Wetness Impregnation And Sputtering For Photocatalytic Co2 Reduction In Aqueous Solution, Nantiya Jantarasorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, we investigated the photocatalytic CO2 reduction in aqueous solution and were carried out in a stirred slurry reactor using Cu/TiO2 catalysts synthesized by incipient wetness impregnation and sputtering method. Effects of Cu loading onto titania support enhancing efficiency of the photocatalytic CO2 reduction in aqueous solution under UV irradiation by a band gap energy modification appeared between valence band and conduction band are narrowed. Cu assisted a selective hydrocarbon compound, this is methane. A comparison between Cu/TiO2 catalysts synthesized by incipient wetness impregnation and sputtering method showed that both methods exhibited similar methane selectivity. Sputtered catalysts are …

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The Development Of Pt/Wox/Al2o3 For 1,3-Propanediol Production From Glycerol, Parama Uttraporn Jan 2018

The Development Of Pt/Wox/Al2o3 For 1,3-Propanediol Production From Glycerol, Parama Uttraporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, the researcher studied the hydrogenolysis of glycerol to 1,3-propanediol, by compared the catalytic activity between AlOOH (boehmite) and g-Al2O3. The catalysts were prepared by wet impregnation method. To investigate the properties, catalysts were characterized by XRD, XPS, BET, H2-TPR, H2-TPD, H2-TPR, SEM-EDX, Py-IR, NH3-IR, and XAS. The type of support showed to be of significance in deciding the activity and the selectivity to 1,3-propanediol. It was found that 2%Pt/WOx/g-Al2O3 gave higher activity and selectivity of 1,3-propanediol, which due to a large amount of active site and Brønsted acid site in the catalyst. The effects of H2 pressure, …

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Electrode Improvement Using Diamond-Like Carbon For Electrochemical Advanced Oxidation In Diuron Degradation, Nimit Kantiyawong Jan 2018

Electrode Improvement Using Diamond-Like Carbon For Electrochemical Advanced Oxidation In Diuron Degradation, Nimit Kantiyawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Diuron is one of the pesticides. Its residual can contaminate natural water resource resulting in environmental and human health problems. Several processes have been used to remove diuron contamination. Nowadays, an electrochemical advanced oxidation process (EAOP) in a microchannel reactor is used to degrade diuron owing to its high efficiency. In this research, the diamond-like carbon (DLC) thin film was used as an electrochemical electrode because it has superior hardness and electrical conductivity. In this research, we have successfully synthesized the DLC thin films using graphite as target material on the surface of 304 stainless steel substrate by the direct …

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Computational Fluid Dynamics Modeling Of The Climate Inside A Chicken House, Nuttaphon Kanjanaudomsuk Jan 2018

Computational Fluid Dynamics Modeling Of The Climate Inside A Chicken House, Nuttaphon Kanjanaudomsuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, most of chicken products are from a closed house system. Climate inside such chicken house can significantly affect chicken welfare and its productivity. Moreover, Thailand is in a tropical region where thermal stress is easily occurred. Suitable operating condition and chicken house design can help improve interior climate which can be evaluated by computational fluid dynamics (CFD) modeling technique. In this study, realizable k-ε model, energy conservation and species transport equations were applied to simulate the air velocity, temperature and relative humidity, respectively, inside the chicken house. The model was validated with measured air velocity, temperature and relative humidity …

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Regeneration Of Zinc Particles For Zinc-Air Battery By Spouted-Bed Electrochemical Reactor, Peerawat Puengthaijaroen Jan 2018

Regeneration Of Zinc Particles For Zinc-Air Battery By Spouted-Bed Electrochemical Reactor, Peerawat Puengthaijaroen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Zinc-air batteries are a promising energy storage system due to its high energy density, low toxicity, and low flammability. They are currently used commercially in low-current devices. Batteries for high-current applications are constructed with zinc particles for increased specific surface areas. Nevertheless, the regeneration of zinc particles from dissolved zincate ions in spent electrolytes has been relatively neglected. We fabricate and study a spouted-bed electrochemical reactor for the regeneration of zinc particles from spent electrolytes. The reactor measures 220 mm high and 130 mm wide with copper as a cathode and stainless steel as an anode. The reactor is separated …

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Dual-Electrolyte System For Suppressing Corrosion Of Aluminum Electrode In Aluminum-Air Flow Battery, Pemika Teabnamang Jan 2018

Dual-Electrolyte System For Suppressing Corrosion Of Aluminum Electrode In Aluminum-Air Flow Battery, Pemika Teabnamang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Aluminum-air batteries have received considerable attention as an electrical power source due to their theoretical specific capacity reaching 2.98 Ah/g. Further, Al-air batteries are abundant and low cost. On the other hand, the aluminum in the batteries has a problem, such that it is subject to self-corrosion in alkaline. Herein, this work concentrates on the aluminum's corrosive behavior and self-corrosion in methanol-3M KOH mixed solution containing different percentages of deionized water i.e. (0, 5, 10 and 20)%wt, using electrochemical (half-cell testing). The aluminum-air battery consists of: aluminum anode | anolyte | anion exchange membrane | catholyte | air cathode. The …

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Reaction Mechanism And Pathway For The Selective Photocatalytic Hydrogenation Of Nitroaromatics Over Tio2 In Alcohols, Pimchanok Nakchuai Jan 2018

Reaction Mechanism And Pathway For The Selective Photocatalytic Hydrogenation Of Nitroaromatics Over Tio2 In Alcohols, Pimchanok Nakchuai

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research investigated the mechanism and photocatalytic performance of the selective photocatalytic hydrogenation of different nitroaromatics (Ar-NO2) in several alcohols under UV light using P25-TiO2 at room temperature and atmospheric pressure. The effect of Pt-deposited P25-TiO2 on the photocatalytic performance was also studied. Ar-NO2 was converted to aminoaromatics (Ar-NH2) with high Ar-NO2 conversion and Ar-NH2 selectivity at nearly 100%. The amounts of Ar-NH2 were proportional with carbonyl compounds at the ratio around 1:3. Acetaldehyde, acetone, and butanone were produced by oxidation of ethanol, 2-propanol, and butanol, respectively. Ethanol exhibited the fastest completed Ar-NO2 conversion due to the most efficient formation …

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Oxidative Dehydrogenation Of Ethanol To Acetaldehyde Over Magnesium Aluminium Layered Double Hydroxides Catalyst, Piriya Pinthong Jan 2018

Oxidative Dehydrogenation Of Ethanol To Acetaldehyde Over Magnesium Aluminium Layered Double Hydroxides Catalyst, Piriya Pinthong

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, the characteristic and catalytic activity of Mg-Al LDH and their metal-modified mixed oxide were investigated. This research was divided into three parts. In the first part, the effect of calcination temperature on catalytic performance via oxidative dehydrogenation of ethanol was elucidated. The results showed that calcination temperature affected the characteristic of Mg-Al LDH, especially basicity. Moreover, the calcination temperature also affected the catalytic performance on oxidative dehydrogenation of ethanol over Mg-Al LDH. The result was consistent with the basicity of catalysts. In the second part, the Mg-Al mixed oxide derived from calcination of Mg-Al LDH was modified …

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Effects Of Immobilization Of Methylalumoxane On Cellulose Support On Ethylene Polymerization Behaviors., Praonapa Tumawong Jan 2018

Effects Of Immobilization Of Methylalumoxane On Cellulose Support On Ethylene Polymerization Behaviors., Praonapa Tumawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

The way to improve the physical properties of polyethylene is done by adding nano-sized filler during the synthetic process. These can be commonly achieved by in situ polymerization. These studies are divided into two parts in this research. Firstly, it investigated the effect of types and amounts of cocatalyst and scavenger of zirconocene catalyst on ethylene polymerization behaviors. In fact, methylalumoxane (MAO) and triethylaluminum (TEA) were used as cocatalyst and scavenger, respectively. The ratios of [Al]MAO/[Zr]cat and [Al]TEA/[Zr]cat were varied during the in situ polymerization of ethylene. The polymerization was performed in a semi-batch autoclave reactor under adiabatic operation at …

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Design Of Solid Oxide Fuel Cell-Molten Carbonate Fuel Cell Combined System For Power Generation And Carbon Dioxide Emission Reduction, Prathak Jienkulsawad Jan 2018

Design Of Solid Oxide Fuel Cell-Molten Carbonate Fuel Cell Combined System For Power Generation And Carbon Dioxide Emission Reduction, Prathak Jienkulsawad

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research concentrates on the design and performance analysis of a solid oxide fuel cell (SOFC) and a molten carbonate fuel cell (MCFC) integrated system with using methane as fuel. Because SOFCs cannot completely use their fuel, there is remaining fuel leaving the system. In addition, the exhaust gas from an SOFC can be directly fed into an MCFC. The integrated fuel cell system shows an electrical efficiency of 55.22%, which is higher than a single fuel cell system. Fuel utilization of both fuel cells, SOFC temperature dramatically affect the performance of the integrated system. Four configurations were next proposed …

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Development Of Suture Pad From Silk-Reinforced Polydimethylsiloxane Composite, Radhitya Banuaji Prastowo Jan 2018

Development Of Suture Pad From Silk-Reinforced Polydimethylsiloxane Composite, Radhitya Banuaji Prastowo

Chulalongkorn University Theses and Dissertations (Chula ETD)

The aim of this research is to investigate the mechanical properties of polydimethylsiloxane reinforced with short silk fibers for suture pad application. The effect of aspect ratio and fibers content of the polydimethylsiloxane reinforced with silk fibers on the properties was evaluated. From the results, tensile modulus and tensile strength of polydimethylsiloxane reinforced with different aspect ratio were increased with increasing aspect ratio and fibers content. The composite with the addition of silk fiber produces higher tear resistance with suture thread compared with pure polydimethylsiloxane. Furthermore, the hardness of polydimethylsiloxane reinforced with short silk fibers was improved with the addition …

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Effect Of Calcination Conditions Of P25-Tio2 On Photocatalytic Selective Hydrogenation Of 3-Nitrostyrene, Saknarin Chaitaworn Jan 2018

Effect Of Calcination Conditions Of P25-Tio2 On Photocatalytic Selective Hydrogenation Of 3-Nitrostyrene, Saknarin Chaitaworn

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, we investigated the effect of calcination of nanocrystalline commercial titanium dioxide catalyst (P25) on photocatalytic selective hydrogenation of 3-nitrostyrene. TiO2 supports were calcined under air, hydrogen and nitrogen atmosphere at various temperatures around 600 to 900°C for 5 hours. In order to investigate characteristic and catalytic properties of TiO2 after treatment, treated-TiO2 were analyzed by using X-ray diffraction (XRD), N2-physisorption, X-ray photoelectron spectroscopy (XPS), UV-Vis spectroscopy (UV-Vis), photoluminescence spectroscopy (PL), thermogravimetric analysis (TGA), scanning electron microscope (SEM). Photocatalytic hydrogenation performance of treated-TiO2 were tested under UV light irradiation. The 3-nitrostyrene consumption was linearly related to the photoluminescence …

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Synthesis Of Black Titanium Dioxide And Effect Of Calcination Conditions And Reducing Agent On Photocatalytic Degradation Of Methyl Orange, Saran Saensook Jan 2018

Synthesis Of Black Titanium Dioxide And Effect Of Calcination Conditions And Reducing Agent On Photocatalytic Degradation Of Methyl Orange, Saran Saensook

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research studied the synthesis and application of black titanium dioxide in the photocatalytic degradation of methyl orange (MO). First, titanium dioxide was prepared via a sol-gel method. Then sodium borohydride was used as the reducing agent in order to synthesize black titanium dioxide. Thus, a 2x2x3 factorial experimental design was employed to assess the significance of the following three factors: (A) calcination temperature (400 and 500 °C); (B) calcination time (5 and 10 h); and (C) the molar ratio of NaBH4 to TiO2 used (0:1, 0.5:1, and 1:1). The removal of MO under UV and visible light were the …

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The Effect Of Mcm-41 Addition To Pva/Pan/Pvp Polymer Electrolyte For Zinc-Air Batteries, Sirinuch Nanthapong Jan 2018

The Effect Of Mcm-41 Addition To Pva/Pan/Pvp Polymer Electrolyte For Zinc-Air Batteries, Sirinuch Nanthapong

Chulalongkorn University Theses and Dissertations (Chula ETD)

A membrane separator is one of the main components in zinc-air batteries playing an important role in controlling the mass transfer for the electrochemical reaction in the battery which determines the battery performance. This work aimed to develop a new membrane separator for the zinc-air battery. Polyvinyl alcohol (PVA), polyacrylonitrile (PAN), polyvinylpyrrolidone (PVP), and their blends were used for the fabrication of separator in this work. In addition, an inorganic nanoparticle with high hydroxide content such as MCM-41 was also applied as the filler for the polymers. The results revealed that the addition of PAN in PVA enhanced the electrolyte …

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Application Of Amine-Functionalized Titanium Dioxide Wrapped In Reduced Graphene Oxide In Photocatalytic Degradation Of Methylene Blue, Sirinya Kanjanapanasont Jan 2018

Application Of Amine-Functionalized Titanium Dioxide Wrapped In Reduced Graphene Oxide In Photocatalytic Degradation Of Methylene Blue, Sirinya Kanjanapanasont

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research investigated the effect of reduced graphene oxide (rGO) addition to amine-functionalized titanium dioxide (APTMS-TiO2). The loading amount of rGO was varied from 0 to 0.05 %wt. Also, the effect of the amount of 3-aminopropyltrimethoxysilane (APTMS) was studied. To synthesize TiO2/rGO catalysts, the amount of APTMS was varied at 2.21 and 22.1 mmol. TiO2 catalyst was synthesized via a sol-gel method. Next, the surface of TiO2 was modified with APTMS by refluxing. Then graphene oxide was wrapped around APTMS-TiO2 and was reduced to rGO using hydrazine and ammonia. In the experiment, the catalyst was dispersed in methylene blue solution …

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Design And Performance Evaluation Of Integrated System Of Hydrotreating And Hydrogen Generation For Bio-Hydrogenated Diesel Fuel Production From Palm Oil, Siriporn Boonsuk Jan 2018

Design And Performance Evaluation Of Integrated System Of Hydrotreating And Hydrogen Generation For Bio-Hydrogenated Diesel Fuel Production From Palm Oil, Siriporn Boonsuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research studied the simulations of the integrated systems between of hydrotreating and hydrogen generation with various selectivity of deoxygenation (DO) pathways (i.e. decarboxylation (DCO2), hydrodecarbonylation (HDCO), and hydrodeoxygenation (HDO)). Two integrated systems were proposed i.e. 1) integrated system between single-step hydrotreating and propane steam reforming (as called "single-step integrated system") and 2) integrated system between two-step hydrotreating (hydrolysis+DO) and glycerol steam reforming (as called "two-step integrated system"). Results revealed that, among DO pathways, DCO2 exhibited the lowest total minimum energy requirement (total MER) and the highest total efficiency for both integrated systems mainly due to lower electricity requirement to …

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Effect Of Ceo2 And La2o3 Promoters On Ni/Al2o3 Oxygen Carrier Performance In Chemical Looping Steam Reforming Of Ethanol For Hydrogen Production, Supalak Isarapakdeetham Jan 2018

Effect Of Ceo2 And La2o3 Promoters On Ni/Al2o3 Oxygen Carrier Performance In Chemical Looping Steam Reforming Of Ethanol For Hydrogen Production, Supalak Isarapakdeetham

Chulalongkorn University Theses and Dissertations (Chula ETD)

The effects of Ce and/or La on NiO/Al2O3 were studied in chemical looping steam reforming of ethanol. Oxygen carriers (OCs) were prepared by wet impregnation method and characterized by various techniques. The redox test was performed by alternating between fuel feed (FFS) and air feed step (AFS) at 500oC. It was found that Ce- and La-doped improved the OCs' properties. A suitable amount of Ce- and La-doping helped increase carbon tolerance due to oxygen storage capacity and mobility. The solubility limit was found at 50 mol% La in solid solution. At higher La-doping, La2O3 dispersed on the surface and adsorbed …

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Preliminary Study On Synthesis And Characterization Of The Star-Shaped Poly (Ethylene Glycol) Through Polycondensation Reaction, Tanchanok Wongkhan Jan 2018

Preliminary Study On Synthesis And Characterization Of The Star-Shaped Poly (Ethylene Glycol) Through Polycondensation Reaction, Tanchanok Wongkhan

Chulalongkorn University Theses and Dissertations (Chula ETD)

The synthesis of star-shaped poly(ethylene glycol) was synthesized from pentetic acid (PA) and poly(ethylene glycol) (PEG) by polycondensation reaction in order to solve the problem of the melt strength of the molten polymer of poly(lactic acid). In this study, the star-shaped poly(ethylene glycol) were synthesized with a different molecular weight of neat poly(ethylene glycol) of 200, 400 and 600 g/mol. After that, the chemical structure of product-PEG was investigated by FTIR and NMR techniques. FTIR spectra of the product-PEG exhibited carbonyl peak due to the reaction between hydroxyl groups of PEG and carboxyl groups of PA. The NMR spectra of …

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Lactic Acid Production From Glucose By Using Divalent Transition Metal Oxide Catalyst On Magnesium Oxide Support Without Alkaline Solution, Tanyatorn Udomcharoensab Jan 2018

Lactic Acid Production From Glucose By Using Divalent Transition Metal Oxide Catalyst On Magnesium Oxide Support Without Alkaline Solution, Tanyatorn Udomcharoensab

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research was studied the effects of the type of divalent metal oxide (Cu, Co, Ni, and Zn) supported on magnesium oxide catalyst using the hexadecyltrimethylammonium bromide (CTAB) as the capping agent with metal loading at 1.5, 5, and 10 mmol/gram-catalyst on lactic acid production from glucose. To achieve the lactic acid production of lower reactor corrosion rate and being environmentally friendly, the reaction was performed in an alkali additive-free environment. The catalysts were synthesized by hydrothermal method and characterized by various techniques. The XRD pattern of spent CuCTAB/MgO and CoCTAB/MgO catalyst showed the reduced metal species indicated the used …

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Effect Of Tio2 Polymorphs And Crystallite Size On The Catalytic Properties Of Pt/Tio2 In The Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Thunyaporn Kaewla-Ueat Jan 2018

Effect Of Tio2 Polymorphs And Crystallite Size On The Catalytic Properties Of Pt/Tio2 In The Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Thunyaporn Kaewla-Ueat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Furfuryl alcohol (FA) is an important intermediate for the manufacturing of many fine chemical products such as furan, resin, vitamin C, and lysine. In this research, the selective hydrogenation of furfural to FA was carried out in a batch reactor at 50ºC, 20 bar H2 and 2 h reaction time using Pt (0.5 wt. %) on TiO2 support. The Pt/TiO2 catalysts were prepared by the incipient wetness impregnation on different commercial TiO2 polymorphs and different temperatures calcined TiO2 sol-gel. Among the commercially available TiO2, it was found that Pt supported on P25 exhibited the highest furfural conversion and selectivity of …

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