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Articles 6001 - 6030 of 6951
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Taxonomy And Systematics Of Earthworm Genus Pontodrilus Perrier, 1874 In Thailand, Teerapong Seesamut
Taxonomy And Systematics Of Earthworm Genus Pontodrilus Perrier, 1874 In Thailand, Teerapong Seesamut
Chulalongkorn University Theses and Dissertations (Chula ETD)
A taxonomic study of the littoral earthworm genus Pontodrilus Perrier, 1874 was critically conducted based on material collected from marine sandy coasts along the east and west sides of the Thai-Malay Peninsula (Thailand and Malaysia) and selected localities in Japan. Comparative material from other parts of Southeast Asia, including Myanmar, Vietnam, Malaysia, Singapore and Indonesia, were also collected. Morphological examination identified almost all of the specimens as Pontodrilus litoralis, but as two morphotypes with some character differences in the diverticulum between them. A combined morphological and molecular phylogenetic analyses supported one of these morphotypes as a new species, P. longissimus. …
The Role Of Hpv16 E1 In Cervical Carcinogenesis, Fern Baedyananda
The Role Of Hpv16 E1 In Cervical Carcinogenesis, Fern Baedyananda
Chulalongkorn University Theses and Dissertations (Chula ETD)
Objectives: This study aimed to determine the expression profile of HPV-16 E1 in cervical samples and the role of E1 in cervical carcinogenesis. In addition, this work also aimed to determine whether the HPV-16 E1 63bp duplication is present in the Thai population.
Methods: One-hundred and twenty-four HPV16 positive cervical samples ranging from normal, CIN1, CIN2/3, and SCC lesions were studied. E1 mRNA expression was determined by ddPCR. Methylation of promoters p97 and p670 was quantified by pyrosequencing, while PCR and sequencing were used to determine the physical state and variations of HPV16 E1 genome. HEK 293T cells were transfected …
Development And Screening Of Chalcones Against Cancer Protein Targets Using In Silico And In Vitro Techniques, Kanyani Sangpheak
Development And Screening Of Chalcones Against Cancer Protein Targets Using In Silico And In Vitro Techniques, Kanyani Sangpheak
Chulalongkorn University Theses and Dissertations (Chula ETD)
Targeted cancer therapy has become one of high potential cancer treatments. Human topoisomerase IIα (hTopoIIα) and Epidermal growth factor receptor tyrosine kinase (EGFR-TK) are proteins that play important roles on cell cycle. The hTopoIIα catalyzes the cleavage and rejoining of double-stranded DNA while EGFR function on cell signaling. Thus, the two proteins have been suggested as molecular target for the development of novel cancer therapeutics. A series of 47 chalcone derivatives was screened against hTopoIIα and EGFR-TK by in silico and in vitro techniques. Chalcone 3d showed a high cytotoxicity with IC50 values of 10.8, 3.2 and 21.1 µM against …
Simulation Of Water Effect On Biodiesel Production Using Waste Cooking Oil Via Ester-Transesterification In A Reactive Distillation Column, Ajala Anantapinitwatna
Simulation Of Water Effect On Biodiesel Production Using Waste Cooking Oil Via Ester-Transesterification In A Reactive Distillation Column, Ajala Anantapinitwatna
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the effect of water content in waste cooking oil (WCO) on the performance of a reactive distillation column for biodiesel production via ester-transesterification. A mixture of triolein and oleic acid was used as a WCO model compound. Amberlyst-15 was used to catalyze esterification while CaO was used for transesterification. From Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model taking into account water absorption for esterification of oleic acid (FFA), biodiesel yield was decreased with increasing of water content in WCO feedstocks. On the other hand, the initial rate of transesterification was increased with increase of amount of water in WCO feedstocks …
Co2 Reforming Of Methane On Ni And Co Containing Γ-Al2o3/Hy Zeolite Supported Catalysts, Anchittha Liu
Co2 Reforming Of Methane On Ni And Co Containing Γ-Al2o3/Hy Zeolite Supported Catalysts, Anchittha Liu
Chulalongkorn University Theses and Dissertations (Chula ETD)
The carbon dioxide reforming of methane is one of the most effective processes to produce syngas while reducing greenhouse gases. In this study, the catalytic activity and coke resistance were studied on the Ni-based catalysts with or without Co (10%wt) over γ-Al2O3-HY zeolite support. Such catalysts were prepared by the sol-gel method with various different metal loadings and Co/Ni ratio. The activity tests on the carbon dioxide reforming reaction were performed in a fixed-bed reactor with the CH4:CO2 feed volume ratio of 1:1 under atmospheric pressure at 700°C which is the best temperature for the catalysts activity. It has been …
Simulation And Evaluation Of Butadiene Production From Ethanol Via One-Step Reaction, Jirawat Imsaard
Simulation And Evaluation Of Butadiene Production From Ethanol Via One-Step Reaction, Jirawat Imsaard
Chulalongkorn University Theses and Dissertations (Chula ETD)
1,3-butadiene is an important compound produced from the steam cracking process. Raising demand for alternatives to fossil fuels has led to an increase in bio-derived ethanol production, which can also be used as a feedstock for 1,3-butadiene synthesis. This research investigated the simulation of 1,3-butadiene production from ethanol using one-step process with 1.AI2O3/ZnO (60:40), 2.MgO-SiO2-Na2O (1:1)(0.1%) and 3.Hf2.5ZM1.6/SiO2 as heterogeneous catalysts. The process simulation was carried out using commercial Aspen plus 8.0 program and the heat utilization efficiency was evaluated by Aspen energy analyzer software. The process optimal condition sequences were identified by adjusting the separation distillation parameters which include …
Preparation Of Carbon/Carbon Composite Xerogels From Resorcinol-Formaldehyde And Cotton Fiber For Electric Double Layer Capacitor, Kasawan Sirichan
Preparation Of Carbon/Carbon Composite Xerogels From Resorcinol-Formaldehyde And Cotton Fiber For Electric Double Layer Capacitor, Kasawan Sirichan
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research used carbon/carbon composite xerogels as an electrode for EDLCs. Cotton fibers were blended with polymer gel which was synthesized through polycondensation between resorcinol and formaldehyde. The reaction was catalyzed by Na2CO3 with distilled water as a solvent. Resorcinol-formaldehyde sol was poured into a vial containing cotton fibers. After gelation at room temperature and curing at 90 oC for a week, the resulting porous monolith was sliced into thin wafers. Then, the composite wafers were exchanged with tert-butyl alcohol, dried by vacuum drying and performed by pyrolysis at a various temperature under a nitrogen atmosphere, respectively. Effect of %cotton …
Effects Of Tio2 Support And Co Addition On Ni/Tio2 Catalysts In Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Kittithad Wonglekha
Effects Of Tio2 Support And Co Addition On Ni/Tio2 Catalysts In Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Kittithad Wonglekha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Furfuryl alcohol is an important chemical intermediate that can be converted into many value-added derivative molecules. It is typically produced by the hydrogenation of furfural using supported metal catalysts. In this work, 15%wt Ni catalysts supported on titania (TiO2) were prepared by incipient wetness impregnation method. The effects of phase composition and average crystallite sizes of TiO2 and Co addition in the range of 1-3 wt% on the catalytic properties of 15 wt%Ni/TiO2 were investigated in the selective hydrogenation of furfural to furfuryl alcohol at 50°C, 20 bar of H2, and 2 h reaction time. It was found that Ni …
Hydrothermal Carbonization Carbon-Based Acid Catalyst For Biodiesel Production, Laddawan Tumkot
Hydrothermal Carbonization Carbon-Based Acid Catalyst For Biodiesel Production, Laddawan Tumkot
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aims to synthesize the production of biodiesel (oleic acid methyl ester) by esterification in the presence of sulfonated hydrothermal carbon based catalyst under microwave irradiation. The catalyst was prepared by hydrothermal carbonization, followed by sulfonation presenting sulfonic acid group as an active site. The catalyst characterization results confirmed good microwave-absorptivity of the catalyst which can be heated directly and accelerate the reaction immediately at the surface of the catalyst. Esterification of oleic acid (OA) with methanol experiments were optimized by using response surface methodology based on central composite design. Three variables: molar ratio of methanol to OA (2.5:1-7.5:1), …
Dehydration Of Ethanol To Diethyl Ether Over Beta Zeolite Catalysts, Montri Thapplee
Dehydration Of Ethanol To Diethyl Ether Over Beta Zeolite Catalysts, Montri Thapplee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The catalytic ethanol dehydration to diethyl ether was investigated using synthesized beta zeolite catalysts having different Na and mixed Na-H form. The Na form in catalyst was synthesized by the hydrothermal process including non-calcined (Na-BEA_N) and calcined (Na-BEA_C) catalysts. The catalysts having different mixed Na-H forms were synthesized under ion-exchange method. In this study, two different cycles were chosen including one cycle (M-BEA_1) and four cycles (M-BEA_4). These catalysts were characterized by various techniques. The catalysts were tested to measure the catalytic activity at atmospheric pressure and the reaction temperature ranged from 150 to 400 °C. The results presented that …
Effect Of Cu Modified Tio2 Catalysts Prepared By Incipient Wetness Impregnation And Sputtering For Photocatalytic Co2 Reduction In Aqueous Solution, Nantiya Jantarasorn
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 …
Computational Fluid Dynamics Modeling Of The Climate Inside A Chicken House, Nuttaphon Kanjanaudomsuk
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 …
Oxidative Dehydrogenation Of Ethanol To Acetaldehyde Over Magnesium Aluminium Layered Double Hydroxides Catalyst, Piriya Pinthong
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 …
Development Of Suture Pad From Silk-Reinforced Polydimethylsiloxane Composite, Radhitya Banuaji Prastowo
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 …
Design Of Solid Oxide Fuel Cell-Molten Carbonate Fuel Cell Combined System For Power Generation And Carbon Dioxide Emission Reduction, Prathak Jienkulsawad
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 …
Effect Of Calcination Conditions Of P25-Tio2 On Photocatalytic Selective Hydrogenation Of 3-Nitrostyrene, Saknarin Chaitaworn
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 …
Synthesis Of Black Titanium Dioxide And Effect Of Calcination Conditions And Reducing Agent On Photocatalytic Degradation Of Methyl Orange, Saran Saensook
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 …
Application Of Amine-Functionalized Titanium Dioxide Wrapped In Reduced Graphene Oxide In Photocatalytic Degradation Of Methylene Blue, Sirinya Kanjanapanasont
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 …
Design And Performance Evaluation Of Integrated System Of Hydrotreating And Hydrogen Generation For Bio-Hydrogenated Diesel Fuel Production From Palm Oil, Siriporn Boonsuk
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 …
Effect Of Ceo2 And La2o3 Promoters On Ni/Al2o3 Oxygen Carrier Performance In Chemical Looping Steam Reforming Of Ethanol For Hydrogen Production, Supalak Isarapakdeetham
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 …
Improving The Efficiency Of Dye-Sensitized Solar Cells With Ultrasonic Spray-Coated Tio2 Electrode That Was Modified By Mno2, Coo, Or Sno2, Supasun Thanadvanichkul
Improving The Efficiency Of Dye-Sensitized Solar Cells With Ultrasonic Spray-Coated Tio2 Electrode That Was Modified By Mno2, Coo, Or Sno2, Supasun Thanadvanichkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the modification of TiO2 electrode by adding the second metal oxide, namely, manganese dioxide (MnO2), cobalt oxide (CoO), or tin dioxide (SnO2) use in for dye-sensitized solar cell (DSSCs). TiO2 and modified TiO2 sols were synthesized via sol-gel methods. The sols were sprayed 500 times onto the fluorine-doped tin oxide glass substrates as a thin film using an ultrasonic spray coater. Finally, the thin film electrode was calcined at 400ºC for two hours. The amount of MnO2, CoO, or SnO2 was varied at 0, 0.1, 0.5, 1.0, and 3.0%wt. The photovoltaic efficiency of DSSCs was measured using …
Lactic Acid Production From Glucose By Using Divalent Transition Metal Oxide Catalyst On Magnesium Oxide Support Without Alkaline Solution, Tanyatorn Udomcharoensab
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 …
The Surface Modification Of Zeolite Y In Composite Selective Layer Of Hollow Fiber Membrane For Separation Of Co2/Ch4 Mixture, Thakorn Wichaidit
The Surface Modification Of Zeolite Y In Composite Selective Layer Of Hollow Fiber Membrane For Separation Of Co2/Ch4 Mixture, Thakorn Wichaidit
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work focused on the fabrication and evaluation of composing hollow fiber mixed matrix membranes (MMMs) incorporated by zeolite Y for CO2/CH4 separation. The effects of surface modification of zeolite Y to improve compatibility of filler and polymer dispersibility of the filler in the polymer matrix on properties and separation performance of the membrane were investigated. A polysulfone (PSF) was used as a support hollow fiber and a selective layer composing of polyether-block-amide (Pebax) and zeolite Y (ZeY) and surface modification of zeolite Y (mo-ZeY) was coated on support. A [3-(2-Aminoethylamino)propyl]trimethoxysilane (AEAPTMS) was used to grafted on surface of pristine …
Parametric Study Of Copper Zinc Tin Sulfide Thin Films By Convective Deposition Method, Thanawat Anantamongkolchai
Parametric Study Of Copper Zinc Tin Sulfide Thin Films By Convective Deposition Method, Thanawat Anantamongkolchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, most of the energy production is from fossil fuel-resources, which is a major source of greenhouse gases. Therefore, several researchers have been looking for the alternative energy that is clean and renewable energy. One of the outstanding alternatives is to utilize solar energy for conversion into electricity. Recently, CZTS (copper zinc tin sulfide, Cu2ZnSnS4) thin film solar cells have received numerous interest because of its decent energy band gap of about 1.4 - 1.6 eV, which matches with the solar spectrum, and its high absorption coefficient. Nevertheless, the manufacture of CZTS solar cells has used sophisticated methods for fabrication …
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
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 …
Carbon Dioxide Capture On Nitrogen-Doped Carbon Nanoparticle Derived From Aromatic Compounds Via Solution Plasma And Nitridation, Phuwadej Pornaroontham
Carbon Dioxide Capture On Nitrogen-Doped Carbon Nanoparticle Derived From Aromatic Compounds Via Solution Plasma And Nitridation, Phuwadej Pornaroontham
Chulalongkorn University Theses and Dissertations (Chula ETD)
The carbon dioxide (CO2) adsorption on nanocarbon (C), oxygen-doped nanocarbon synthesized from benzene and a mixture of benzene and metal working fluid (MWF), respectively, via solution plasma process (SPP) have been revealed in this study. Firstly, they showed low CO2 adsorption capacity at 25 °C. However, their capacities were enhanced by nitridation under ammonia atmosphere at high temperature. The maximum CO2 adsorption capacity of 1.63 mmol g-1 was achieved on nitrogen-oxygen-codoped nanocarbon obtained from SPP discharging a mixture containing 15 vol% MWF nitrided at 800 °C (noC15(800)). The characterizations revealed that the micropososity and nitrogen functionality on the adsorbent are …
Computational Fluid Dynamics Of Fluid Transport And Deposition Of Particles Under Unsteady Flow In Human Fluid System, Ratchanon Piemjaiswang
Computational Fluid Dynamics Of Fluid Transport And Deposition Of Particles Under Unsteady Flow In Human Fluid System, Ratchanon Piemjaiswang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Computational fluid dynamics has been widely used to investigate flow phenomena in many different applications. This study focuses on the development of computational fluid dynamic model in biomedical applications, including the flow within human respiratory system and the flow within human circulating system. For the model of respiratory system, electrostatic charge model was coupled, and the effect of breathing frequency was investigated. The accomplishment of the study will gain better understanding of the hydrodynamics when applying the electrostatic field, and will use to identify the potential aerosol deposition location. The aerosol properties and morphologies were also considered their effect on …
Development Of Optical Sensor For Detection Of Chloride Ions And Electrochemical Sensor For Detection Of Clinical Indicators, Abdulhadee Yakoh
Development Of Optical Sensor For Detection Of Chloride Ions And Electrochemical Sensor For Detection Of Clinical Indicators, Abdulhadee Yakoh
Chulalongkorn University Theses and Dissertations (Chula ETD)
This dissertation concentrated on the development of nanomaterials-based miniaturized platforms for the detection of some important compounds/indicators from environmental, pharmaceutical, and clinical application. This dissertation can be classified into two main parts: (1) development of nanomaterials-based miniaturized platforms for optical sensing application, and (2) development of nanomaterials-based miniaturized platforms for electrochemical sensing applications. In the first part, two sub-sections were discussed. For the first sub-section, the paper-based colorimetric sensor for chloride ion determination using silver nanoprisms was developed. Using a smartphone as an optical readout, the color change from the oxidative etching of the silver nanoprisms to the silver nanospheres …
Development Of Sr₂Fetio[₆-Delta] Electrode For Solid Oxide Fuel Cell, Ausa Potong
Development Of Sr₂Fetio[₆-Delta] Electrode For Solid Oxide Fuel Cell, Ausa Potong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Sr₂FeTi₁-x(Nb,V)xO₆ (x=0.05-0.50) double perovskites have been synthesized by the substitution of Nb and V on Ti sites of Sr₂FeTiO₆ (SFT) and tested as electrode for intermediate temperature solid oxide fuel cell (IT-SOFC). The XRD analyses indicated Sr₂FeTi₀.₉₅Nb₀.₀₅O₆ and Sr₂FeTi₀.₉₅V₀.₀₅O₆ were pure and the impurities, Sr(FeNb) ₀.₅O₃ and Sr3(VO4) ₂, were found with the increasing of Nb and V contents in SFT. By small addition of Nb and V in SFT, the electrical conductivity and electrochemical property of SFT was improved. Among the various oxide examined, Sr₂FeTi₀.₉₅Nb₀.₀₅O₆ and Sr₂FeTi₀.₉₅V₀.₀₅O₆ showed the highest electrical conductivity of 2.44 and 3.93 S cm⁻¹, respectively, …
Study Of Substitution Reaction On Ring A Of Estradiol, Chanoknun Boonyaratsewee
Study Of Substitution Reaction On Ring A Of Estradiol, Chanoknun Boonyaratsewee
Chulalongkorn University Theses and Dissertations (Chula ETD)
Estradiol-conjugated anticancer drugs are the effective strategy that could specifically combat breast cancer cells, while minimizing the toxicity of the drug toward normal cells. Estradiol has been previously conjugated with drugs mostly at rings B, C and D. Functionalizations at ring A of estradiol introduce new types of conjugated drugs that could improve both the selectivity and efficiency in binding with estrogen receptor (ER). Using 4-cresol as the model, the nitration at meta-position was achieved, although with unsatisfied result of only 6% overall yield of the product. The practical results derived from diazo coupling on ortho-position of 4-cresol, which led …