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Antiproliferative Activity Against Jurkat Cells Of Sahm1 Peptide Conjugated Gold Nanoparticles, Mukthida Thippayamonta
Antiproliferative Activity Against Jurkat Cells Of Sahm1 Peptide Conjugated Gold Nanoparticles, Mukthida Thippayamonta
Chulalongkorn University Theses and Dissertations (Chula ETD)
In general, treatments of cancer may involve medication, surgery, radiation and chemotherapy. Although these treatments are successful at a certain satisfactory level, their side effects are not acceptable for some patients. Thus, many researches have been investigated alternative methods to cure cancer. A technique of interest is the use of targeted drug therapy in which drug is designed to selectively kill only the cancer cells and to do no harm on the normal cells. Stapled α-helical peptide derived from mastermind-like I or SAHM1 is a small peptide which has been reported to have antiproliferative activity against cancer cells. However, its …
Separation And Purification Of Lactic Acid From Fermentation Broth By Reverse Osmosis, Natnirin Phanthumchinda
Separation And Purification Of Lactic Acid From Fermentation Broth By Reverse Osmosis, Natnirin Phanthumchinda
Chulalongkorn University Theses and Dissertations (Chula ETD)
Brackish water reverse osmosis (BWRO) and seawater reverse osmosis (SWRO) membranes were used in the 2-stage reverse osmosis (RO) unit to recover, pre-purify, and pre-concentrate lactic acid. Calcium lactate (CaLAC), sodium lactate (NaLAC), and ammonium lactate (NH4LAC) were used as model feed solutions. The operating pressure showed a pronounced effect on lactate passage through the first BWRO unit, and the Donnan exclusion effect and hydrogen bonding were responsible for cation rejection. Calcium ions were rejected at the BWRO unit because of low diffusion rate and charge interaction at the surface. However, monovalent ions formed hydrogen bonds with the carbonyl group …
Bioactive Peptide Derived From Trypsin Hydrolysis Of Unicellular Cyanobacterium Synechococcus Sp., Rutairat Suttisuwan
Bioactive Peptide Derived From Trypsin Hydrolysis Of Unicellular Cyanobacterium Synechococcus Sp., Rutairat Suttisuwan
Chulalongkorn University Theses and Dissertations (Chula ETD)
A free radicals can promote denaturing reactions in many cellular components, which create oxidative stress and it results to damage in body tissue. The free radicals can causing many diseases including heart diseases, Alzheimer, inflammation and cancer. This research aimed to investigate the effect of bioactive peptides derived from Synechococcus sp. cultured for 21 days on antioxidant, anti-inflammation and anticancer activities. The Synechococcus sp. protein hydrolysate was prepared by trypsin digest and purified by ultrafiltration with molecular weight cut off membranes of 10, 5 and 3 kDa. The MW <3 kDa fraction showed the highest NO, ABTS and DPPH radical scavenging activities with IC50 values of 34.51±9.8 µg protein/mL, IC50 11.54±0.3 µg protein/mL and IC50 13.63±0.15 µg protein/mL, respectively. The F2 fraction from gel filtration chromatography showed the strongest NO and ABTS radical scavenging activities with IC50 values of 7.68±0.64 µg protein/mL and 9.74±0.2 µg protein/mL, respectively. The F2 was purified by RP-HPLC to yield four fractions. The 30 – 40 min sub-fraction (F2-4) was selected for further analysis by mass spectroscopy. Five isolated peptides with amino acid sequences of AILQSYSAGKTK; 1,265.69 Da, ALNKTHLIQTK; 1,265.74 Da, LLVHAPVK; 875.55 Da, IPDAHPVK; 875.48 Da and VVVLRDGAVQQLGTPR; 1,706.97 Da were identified. The F2-4 had higher DPPH and NO radical scavenging activity compared to the synthetic peptide. Moreover, AILQSYSAGKTK had the highest ABTS radical scavenging activity. Furthermore, the F2 fraction protected oxidation-induced DNA damage in pBR322, pKS and pUC19 cells. F2 fraction was selected to study anti-inflammatory and anticancer properties. Anti-inflammatory effect, F2 fraction showed no cytotoxicity toward RAW264.7 macrophage cells. RT-PCR and qRT-PCR results showed that F2 reduced gene expression of pro-inflammatory cytokines iNOS, TNF-α, COX-1, COX-2 and IL-6. For anticancer activity, F2 fraction showed high anticancer activities in the human colon cancer cells (SW620) according to cytotoxic activity (MTT assay), with IC50 values of 106.58±21.46 µg protein/mL. The F2 fraction activated the apoptotic pathway in SW620 cells after treatment for 24, 48 and 72 hours. The highest activities of caspases 3, 8 and 9 were observed after treatment for 72 hours. These findings suggested that unicellular cyanobacterium Synechococcus sp. may be used to develop for natural anti-inflammation and natural anticancer drugs.
Specific Binding Of Hlas And Antigenic Peptides Associated With Behcet's Disease And Systemic Sclerosis, Sirilak Kongkaew
Specific Binding Of Hlas And Antigenic Peptides Associated With Behcet's Disease And Systemic Sclerosis, Sirilak Kongkaew
Chulalongkorn University Theses and Dissertations (Chula ETD)
Human leukocyte antigen (HLA) molecules are essential components for immune functions. There play a major role to present antigenic-peptide for T-cell receptor (TCR) recognition and immune activation. Association between HLA genes and infectious as well as autoimmune diseases are identified genetic risk factors. For instance, Behçet’s disease (BD) and systemic sclerosis (SSc) are autoimmunity result in chronic of multisystemic inflammation and visceral fibrosis, respectively. To investigate the link of HLAs correlated with self-peptides for BD and SSc, molecular dynamics (MD) simulations were applied on the HLAp complexes. For BD, a self-peptide named MICA-TM was modeled for two BD-association such as …
Antibacterial Agents From Dracaena Cochinchinensis (Lour.) S.C.Chen And Eleutherine Americana (Aubl.) Merr. Ex K. Heyne, Ritbey Ruga
Chulalongkorn University Theses and Dissertations (Chula ETD)
Fifteen compounds including two new anthraquinones (118-119), two naturally occurring new compounds (116-117) and eleven known compounds were successfully isolated from the CH2Cl2 extracts of Dracaena cochinchinensis and Eleutherine americana i.e. dihydrochalcones (5 and 23), pterostilbene (27), homoisoflavanones (15 and 82-84), naphthalenes (85 and 116), pyranonaphthoquinone (86) and anthraquinones (99-100 and 117-119). Among isolated compounds, (+)-eleutherin (86) was the most potent antibacterial agent against Propionibacterium acnes KCCM 41747, Staphylococcus aureus ATCC 25923, Streptococcus sobrinus KCCM 11898, Streptococcus mutans ATCC 25175 and Salmonella typhi ATCC 422 with inhibition zones of 14.7 to 18.0 mm and MIC values of 0.24 to 7.8 …
Adaptation Of Terrilactibacillus Laevilacticus Sk5-6 For Growth And D-Lactic Acid Production In A Low Yeast Extract Concentration Medium, Srettapat Limsampancharoen
Adaptation Of Terrilactibacillus Laevilacticus Sk5-6 For Growth And D-Lactic Acid Production In A Low Yeast Extract Concentration Medium, Srettapat Limsampancharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
Lactic acid has been extensively used in food, personal care, and pharmaceutical products. Besides, lactic acid can be used as the sole feedstock in the synthesis of polylactic acid (PLA), the biodegradable plastic. The demand of the bioplastics including PLA has been increased due to the environmental impact of petroleum based plastic; therefore, this expedited the market demand of lactic acid. It should be noted that the polymer grade lactic acid is unlike those commercially available products for food and pharmaceutical applications. The high purity of stereoisomer either D-lactate or L-lactate is mandatory in PLA polymerization. In addition, the production …
Tyrosinase Inhibitors From Bark Of Talawrinta (Manilkara Kauki (L.) Dubard, Sirinada Srisupap
Tyrosinase Inhibitors From Bark Of Talawrinta (Manilkara Kauki (L.) Dubard, Sirinada Srisupap
Chulalongkorn University Theses and Dissertations (Chula ETD)
Melanin is essential for protecting human skin from ultraviolet radiation. However, its overproduction in the basal epithelial layer leads to hyperpigmentary disorders of the skin such as melasma, blemish and age spots. Tyrosinase is one of key enzymes in melanogenesis. Manilkara kauki (L.) Dubard or Talawrinta is one of the plants in genus Manilkara of Sapotaceae family. This study attempted to investigate in vitro total phenolic and flavonoid contents, antioxidant and tyrosinase inhibitory activities of crude extract of different parts of M. kauki and purify tyrosinase inhibitors from stem barks of M. kauki. Methanol and aqueous crude extracts of fruits, …
Bioactive Compounds From Songkhla Province Mangrove-Derived Endophytic Fungi And From Heart-Leaved Moonseed Tinospora Baenzigeri Forman, Sujitra Hanthanong
Bioactive Compounds From Songkhla Province Mangrove-Derived Endophytic Fungi And From Heart-Leaved Moonseed Tinospora Baenzigeri Forman, Sujitra Hanthanong
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study has evaluated biological activities of isolated compounds from Tinospora baenzigeri stems collecting from two different areas, and from mangrove-derived endophytic fungi isolated from trees inhabiting in Songkhla province. Four new rearranged clerodane-type diterpenes (66-69), one new glycoside (70), and six known compounds (61, 71-75), were extracted from plant obtained from local market in Bangkok. Twelve compounds including a new rearranged clerodane-type diterpene (76), a new rearranged clerodane glycoside (77), five known compounds (44, 78-81), and five compounds counting 61, 66, 70 and 74-75 were obtained from plant collected in Bueng Kan Province. Structures of new compounds 66-69 and …
Increasing Viability Of Probiotic Bacteria Co-Encapsulated With Prebiotic For Disease Resistance In White Shrimp Litopenaeus Vannamei, Suppharada Jantarathin
Increasing Viability Of Probiotic Bacteria Co-Encapsulated With Prebiotic For Disease Resistance In White Shrimp Litopenaeus Vannamei, Suppharada Jantarathin
Chulalongkorn University Theses and Dissertations (Chula ETD)
The main problem of probiotics is the low survival of these microorganisms in food products and sensitive to harsh conditions during food processing, storage and in the gastrointestinal tract. The suitable technology for protecting probiotics to maintain the high number of probiotic cells in product and survived within the host which is microencapsulation technique. The aim of this work was to investigate the effect of prebiotic which is inulin or Jerusalem artichoke on the survival of encapsulated Lactobacillus acidophilus TISTR 1338 within alginate matrix and double-coated with chitosan after freeze-drying process and heat processing at 70°C for 60 min. Furthermore, …
Optimization Of Preparation Protein Hydrolysate By Protease G6 Using Response Surface Methodology And Free Radical Scavenging Activities From Feather Meal, Waleeporn Pibulpol
Optimization Of Preparation Protein Hydrolysate By Protease G6 Using Response Surface Methodology And Free Radical Scavenging Activities From Feather Meal, Waleeporn Pibulpol
Chulalongkorn University Theses and Dissertations (Chula ETD)
The aim of this research was to study the optimal condition for chicken feather meal protein hydrolysate production using a microbial protease, Protease G6. The experimentation was conducted using Central Composite Design (CCD) and Response Surface Methodology (RSM). The three independent variables including temperature (°C), time and enzyme-substrate ratio were studied. Optimization process for obtaining high yield of chicken feather meal protein hydrolysate was performed using response surface methodology (RSM) by optimizing a combination of three independent variables namely, temperature (41.59 – 58.41°C), time (0:38 - 7:21 h) and enzyme-substrate ratio (0.8 – 9.2) with degree of hydrolysis (DH) as …
Tyrosinase Inhibitors From Sapodilla Plum Manilkara Zapota L., Sutthiduean Chunhakant
Tyrosinase Inhibitors From Sapodilla Plum Manilkara Zapota L., Sutthiduean Chunhakant
Chulalongkorn University Theses and Dissertations (Chula ETD)
Six different parts of Manilkara zapota which consisted of barks, flowers, fruits, leaves, roots and seeds were investigated for total phenolic content, total flavonoid content, antioxidant and antityrosinase activities. Methanol crude extract of flowers showed the highest total phenolic content (368.73 ± 0.65 mg GAE/g), while methanol crude extracts of seeds and roots showed high total flavonoid content (90.21 ± 0.57 and 89.03 ± 1.00 mg QE/g, respectively). Methanol crude extract of seeds showed the strongest DPPH (IC50 282.05 ± 0.60 μg/mL) and ABTS (IC50 205.11 ± 0.89 μg/mL) radical scavenging activities and showed the highest FRAP value of 296.46 …
Optimization Of D-Lactic Acid Production By Terrilactibacillus Laevilacticus Sk5-6 And Fermentation Process Scale Up In 30 Litre-Fermentor, Woraphot Toliang
Optimization Of D-Lactic Acid Production By Terrilactibacillus Laevilacticus Sk5-6 And Fermentation Process Scale Up In 30 Litre-Fermentor, Woraphot Toliang
Chulalongkorn University Theses and Dissertations (Chula ETD)
PLA, which is one of biodegradable plastic stereocomplex is made by block polymerization of optically pure L- and D-lactic acid. With stereoblock structure, heat and mechanical properties of PLA products can be improved. Thus, the demand of D-lactic acid has been increased. However, the market supply is still limited. In-house work reported that Terrilactibacillus laevilacticus SK5-6, the novel bacterium has been isolated from soil and later identified as the potent D-lactic acid producer. Moreover, it could produce high D-lactic acid from glucose with high optical purity in flask scale. To improve the fermentation performance, further process optimization was conducted in …
Malfunctioned Pacemaker And Business Operator's Liability In Us, Eu And Australia: Implication For Thailand, Peerasak Ounhachoke
Malfunctioned Pacemaker And Business Operator's Liability In Us, Eu And Australia: Implication For Thailand, Peerasak Ounhachoke
Chulalongkorn University Theses and Dissertations (Chula ETD)
At the present time, for the purpose of healthcare, pacemakers and other implantable medical devices are playing a significant role. However, the severity of level of damage arising from a malfunctioning pacemaker may be higher when compared with other simple products because when taking into consideration the characteristics and purpose of a pacemaker, it was normally implanted into a patient's body to control an abnormal heartbeat rate; therefore, a malfunctioned pacemaker may potentially cause harmful consequences, and in the worst scenario, death. From the abovementioned issue, the aspects of this research focused on the evolution of the laws and regulations …
Legal Measures For Employer To Reach Fair Practice In Organizational Restructuring In Thailand, Pitsanuchai Thongtha
Legal Measures For Employer To Reach Fair Practice In Organizational Restructuring In Thailand, Pitsanuchai Thongtha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Restructuring, a normal managerial task of entrepreneurship, can lift up an enterprises' competitiveness potential in business societies. Restructuring will affect to the rights of all people in the enterprise. Labor laws and regulations not only provide adequate protection for employees, but also promote the flexibility to the business sectors. The employment relationships are involved with the actions of three parties - employees, employers and the government - that must substantially cooperate in order to establish efficient labor regulations. Thai labor laws which relate to working condition adjustment and dismissal are obsolete. It provides too much power for the courts in …
Diversity Of Mosses In Phu Kradueng National Park, Loei Province, Patsakorn Ajintaiyasil
Diversity Of Mosses In Phu Kradueng National Park, Loei Province, Patsakorn Ajintaiyasil
Chulalongkorn University Theses and Dissertations (Chula ETD)
The study of mosses diversity in Phu Kradueng National Park, Loei Province was explored from December 2014 to December 2016. The samples were collected along the 6 natural trails. A total of 501 samples were identified into 30 families, 55 genera, 100 species, 5 subspecies, and 9 varieties. Three families of mosses namely Sphagnaceae, Fissidentaceae, and Leucobryaceae were common families which included 11, 9 and 7 taxa, respectively. Additionally, the most common microhabitat was saxicolous with 45 species. The second and third common microhabitats were terrestrial and corticolous with 43 and 37 species, respectively. Additionally, there are 4 species which …
Catalytic Ethanol Dehydration To Diethyl Ether Over Palladium-Modified Phosphorus Gamma Alumina Catalysts, Chakkrit Khaochartchai
Catalytic Ethanol Dehydration To Diethyl Ether Over Palladium-Modified Phosphorus Gamma Alumina Catalysts, Chakkrit Khaochartchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
The gamma alumina (γ-Al2O3) catalyst was modified with phosphorous (P) by acid activation technique and palladium (Pd) by the incipient wetness impregnation technique. The obtained catalysts were characterized with various techniques including X-ray diffraction (XRD), inductively coupled plasma (ICP), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX), N2 physisorption, ammonia temperature-programmed desorption (NH3-TPD), and thermogravimetric analysis (TGA). In addition, these modified catalysts were tested in ethanol dehydration reaction in a fixed-bed microreactor to determine ethanol conversion and product yield at the atmospheric pressure with temperatures ranging from 200-400oC. From the results, the phosphorous modification diminished the amount of …
Co2 Methanation Over Nial2o4 Spinel - Based Catalysts, Chanya Thamma
Co2 Methanation Over Nial2o4 Spinel - Based Catalysts, Chanya Thamma
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the present work, a series of NiO/NiAl2O4 catalysts were prepared by co-precipitation method with molar ratio of Ni/Al equal 1/2 at different precipitation temperatures (30 and 80oC) and calcination temperatures (500, 700, 900, and 1200oC). The catalyst properties were characterized by using N2 physisorption, X-ray diffraction, H2 - TPR, SEM, and TEM. The NiO/NiAl2O4 precipitated at 80oC and calcined at 900oC showed the best activity in CO2 methanation at 350oC with conversion 92% and 100% methane selectivity without CO formation. The optimal of NiO and NiAl2O4 composition at 24.7% and 75.3%wt could provide a stabilizing effect preventing the metal …
Dehydration And Oxidative Dehydrogenation Of Ethanol Over Sba-15 Based Catalysts Prepared By Sol-Gel And Hydrothermal Methods, Chaowat Autthanit
Dehydration And Oxidative Dehydrogenation Of Ethanol Over Sba-15 Based Catalysts Prepared By Sol-Gel And Hydrothermal Methods, Chaowat Autthanit
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this present study, characteristics and catalytic properties of zirconium (Zr) and bimetal (Zr and La) containing in SBA-15 catalysts and different VOx/SBA-15 catalysts were determined and well related. The study was divided into three parts. Regarding to the first part, zirconium (Zr) and bimetal (Zr and La) containing in SBA-15 synthesized by sol-gel and hydrothermal methods were compared. The results showed that the incorporation of Zr and bimetal (Zr and La) had an effect on the textural properties of both synthesized SBA-15 catalysts. Surface acidity in the SBA-15 suggests new active sites, especially Brønsted acid type. In the second …
Functionalization Of Carbon Nanohorns And Their Catalysis Applications, Chompoopitch Termvidchakorn
Functionalization Of Carbon Nanohorns And Their Catalysis Applications, Chompoopitch Termvidchakorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Carbon nanohorns (CNHs) synthesized by gas-injected arc-in-water method were functionalized in this study. Metal (Ni, Cu, Fe, Pd, and Pt) and their alloy (NiCu, NiFe, NiPd, and NiPt) hybridized with CNHs were successfully produced. In addition, thermal and acid treatment was applied on the hybridized materials. Effect of metal loading and functionalizing conditions on characteristics of CNHs and functionalized CNHs was examined based on transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), N2 sorption, Raman spectroscopy, Fourier transform infrared (FT-IR) spectrometer, temperature programmed desorption of ammonia (NH3-TPD) analysis. The functionalized CNHs were applied as a catalyst in …
Conversion Of Glucose To Levulinic Acid By Fe/Carbon Nanoparticle Catalyst Synthesized From Lubricant Oil And Ferrocene, Jirarat Kaewngam
Conversion Of Glucose To Levulinic Acid By Fe/Carbon Nanoparticle Catalyst Synthesized From Lubricant Oil And Ferrocene, Jirarat Kaewngam
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, production of levulinic acid which is one of promising chemical substances derived from biomass has been intensively investigated. Different catalyst types have been employed to produce levulinic acid from glucose including zeolite, metal phosphate and alumina. However, carbon based catalysts with high thermal stability, ease of surface functionalization and acid-base resistance were not widely studied. In this thesis, carbon nanoparticles synthesized from lubricant oil and ferrocene via co-pyrolysis was fully studied for glucose conversion to levulinic acid. The effect of carbon nanoparticles acid treatment was mainly investigated in terms of glucose conversion and levulinic acid yield. Pristine magnetic carbon …
Effects Of Carbon Fiber And Glass Fiber On Shape Memory Polymers Based On Benzoxazine-Epoxy Binary Systems, Jutamart Plylaharn
Effects Of Carbon Fiber And Glass Fiber On Shape Memory Polymers Based On Benzoxazine-Epoxy Binary Systems, Jutamart Plylaharn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Recovery stress is an important parameter of shape memory polymers. Generally, recovery stress in SMPs can be enhanced by using fiber reinforced composites with suitable reinforcing agents such as carbon fiber or glass fiber. We aim to study effects of carbon fiber and glass fiber on thermal, mechanical, and shape memory properties of benzoxazine-epoxy SMPs, particularly on recovery stress enhancement. The compositions of carbon fiber and glass fiber reinforced benzoxazine-epoxy SMPs were in a range of 30 to 50vol%. The carbon fiber and glass fiber reinforced benzoxazine-epoxy shape memory polymer was compression-molded at 170oC under a pressure of 10 MPa …
Photocatalytic Degradation Of Methylene Blue Over Polydopamine-Ag/Tio2, Kamonthip Tammarakwattana
Photocatalytic Degradation Of Methylene Blue Over Polydopamine-Ag/Tio2, Kamonthip Tammarakwattana
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the effect of silver and polydopamine (PDA) doping on TiO2 catalysts for the photocatalytic degradation of methylene blue in aqueous phase. Titanium dioxide was synthesized via a sol-gel method and was calcined at 400 °C for two hours. Silver was loaded onto TiO2 by an incipient wetness impregnation method. The amount of Ag was varied from 0.5%wt to 3%wt. Then polydopamine-Ag/TiO2 catalyst was prepared by an impregnation method, using dopamine as a precursor. The amounts of polydopamine were 5%wt and 10%wt. All catalysts were characterized by N2 physisorption, ICP-OES, XRD, FTIR, CO chemisorption, Photoluminescence, and UV-Visible spectrophotometry. …
Performance Comparison Of Different Membrane Micro-Channel Reactors For Methanol Production From Biogas And Hydrogen, Khunnawat Ountaksinkul
Performance Comparison Of Different Membrane Micro-Channel Reactors For Methanol Production From Biogas And Hydrogen, Khunnawat Ountaksinkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
In order to integrate simultaneous methanol production with biogas upgrading in a single unit, the computational fluid dynamics (CFD) models of a triple pipe tubular membrane reactor (TMR) and a planar membrane micro-structured reactor (MMR) were established via COMSOL Multiphysics 5.3a and compared their effect on reactor performance under predetermined condition. For the conceptual design of these reactors, the channel inside the reactors can be divided into three parts; biogas channel (BC), reaction channel (RC) and sweep gas channel (SC). The CO2 in biogas entering into BC is separated through CO2 selective membrane to produce methanol inside RC. Afterwards, water …
Computational Fluid Dynamic Study Of Sorption Enhanced Steam Reforming Of Methane/Ethanol In Circulating Fluidized Bed System, Kiattikhoon Phuakpunk
Computational Fluid Dynamic Study Of Sorption Enhanced Steam Reforming Of Methane/Ethanol In Circulating Fluidized Bed System, Kiattikhoon Phuakpunk
Chulalongkorn University Theses and Dissertations (Chula ETD)
Two-dimensional fluid dynamic models were used to optimize and design a proper pilot-scale system for sorption enhanced steam methane reforming (SESMR) and sorption enhanced steam reforming of ethanol (SESRE) in a circulating fluidized bed reactor (CFBR) using Ni-based catalyst and dolomite as sorbent. The CFBR system was separately designed as 3 parts: including a SESMR riser, a SESRE and a regenerator. The SESMR riser could get H2 purity reached equilibrium of 98.58% in dry basis with the highest H2 flux of 0.301 kg/m2s when operating with steam to carbon ratio of 4 mol/mol, gas velocity of 6 m/s, inlet temperature …
Synthesis Of Ptco/Tio2 Catalysts By Flame Spray Pyrolysis For Selectiive Hydrogenation Of Furfural To Furfuryl Alcohol, Kitima Kruachao
Synthesis Of Ptco/Tio2 Catalysts By Flame Spray Pyrolysis For Selectiive Hydrogenation Of Furfural To Furfuryl Alcohol, Kitima Kruachao
Chulalongkorn University Theses and Dissertations (Chula ETD)
The selective hydrogenation of furfural to furfuryl alcohol (FA) was carried out in a batch reactor at 50 ̊C and 20 bar H2 using Pt-Co/TiO2 with 0.5 wt%Pt and 0-0.8 wt%Co. The catalysts were characterized by X-ray diffraction (XRD), N2-physisorption, X-ray photoelectron spectroscopy (XPS), H2-temperature programmed reduction (H2-TPR), atomic absorption spectroscopy (AAS), CO-pulse chemisorption and transmission electron microscopy (TEM). Addition of Co into monometallic (I) Pt/TiO2 catalyst increased both furfural conversion and FA selectivity because it prevented anatase to rutile transformation of TiO2 and increased the interaction between metal and TiO2. However, Co adding into monometallic (F) Pt/TiO2 catalyst resulted …
Effects Of Polyol Molecular Weights On Thermally Reversible Light Scattering Behaviors Of Benzoxazine-Urethane Copolymers, Kittipon Bunyanuwat
Effects Of Polyol Molecular Weights On Thermally Reversible Light Scattering Behaviors Of Benzoxazine-Urethane Copolymers, Kittipon Bunyanuwat
Chulalongkorn University Theses and Dissertations (Chula ETD)
The thermally reversible light scattering behaviors of benzoxazine-urethane copolymer was investigated in this work. Benzoxazine monomers (BA-a) were synthesized by the solventless synthesis technique from bisphenol-A, para-formaldehyde, and aniline with the molar ratio of 1:4:2, respectively. Urethane prepolymer was prepared by reacting poly(propylene glycol) (Mw = 1000, 2000, or 3000 g/mol) with toluene diisocyanate (TDI) at the molar ratio of 1:2 under a nitrogen atmosphere. The obtained urethane prepolymer (PU) was labelled as PU1K, PU2K, and PU3K with respect to the molecular weights of polyether polyol employed in the preparation step. Urethane prepolymer and benzoxazine monomers were crosslinked during the …
Development Of High Performance Ballistic Armor From Varied Fiber Reinforced Polybenzoxazine Composites, Manunya Okhawilai
Development Of High Performance Ballistic Armor From Varied Fiber Reinforced Polybenzoxazine Composites, Manunya Okhawilai
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, a hard ballistic armor based on fiber reinforced polybenzoxazine/polyurethane (PBA/PU) composite as human body armor was developed to protect the 7.62×51 mm projectile at a velocity of 847±9.1 m/s according to National Institute of Justice at test level III. The hard armor consisted of two main panels, i.e., strike panel to destroy the tip of projectile which was made from glass fiber reinforced PBA composite and absorption panel from aramid fiber reinforced PBA/PU composite to absorb impact energy. It was found that S glass composite exhibited a greater performance than E glass composite having the same number …
Nanocomposite Membranes Incorporated With Graphene Oxide For Co2/Ch4 Separation, Nadia Norahim
Nanocomposite Membranes Incorporated With Graphene Oxide For Co2/Ch4 Separation, Nadia Norahim
Chulalongkorn University Theses and Dissertations (Chula ETD)
Biogas is an alternative energy produced by anaerobic digestion of organic matter. Generally, raw biogas consists of methane (CH4), carbon dioxide (CO2), few amount of hydrogen sulfide (H2S) and traces of water vapor. Nowadays, upgrading raw biogas is required in order to achieve higher calorific value and meet fuel standard by removal of CO2. In this study, composite membranes of PEG 400/Pebax 1657 blended polymer with graphene oxide (GO) and amine functionalized graphene oxide (Fn-GO) were successfully developed for CO2/CH4 gas separation. The effects of graphene oxide, amine functionalized graphene oxide and PEG 400 additions on CO2/CH4 separation performance were …
Synthesis Of Cu2znsns4 For Thin Film Solar Cells Prepared By Solution-Based Processes, Napaporn Khothong
Synthesis Of Cu2znsns4 For Thin Film Solar Cells Prepared By Solution-Based Processes, Napaporn Khothong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Copper zinc thin sulphide (Cu2ZnSnS4: CZTS) thin films were synthesized via convective deposition method at various deposit speeds based on sol-gel precursor of 2-methoxyethanol solution with metal chlorides and thiourea. The deposited films were annealed at 340 to 550ºC under N2 atmosphere to yield high quality CZTS films. The compositions, morphology, phase, and optical properties of the CZTS films were characterized by Energy dispersive X-ray analysis (EDX), Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and UV-Vis spectrophotometer, respectively. The formation films exhibited in kesterite structure and the band gap was about 1.4-1.5 eV. The CZTS films also applied …
Characteristics And Catalytic Properties Of Agli/Sio2 Catalysts On Different Silica Supports For Oxidative Dehydrogenation Of Ethanol To Acetaldehyde, Narawich Mukda
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work focuses on investigation of the oxidative dehydrogenation and non-oxidative dehydrogenation of ethanol over AgLi/SiO2 catalysts to produce acetaldehyde by having three different types of silica support, spherical silica particle (small particle size; SPS), medium silica particle size (MPS), and large silica particle size (LPS). The spherical silica particle (SSP) was synthesized using the sol-gel method, whereas SiO2 (MPS) and SiO2 (LPS) were obtained from commercial suppliers. AgLi/SiO2 catalysts were prepared by incipient wetness co-impregnation method. The physicochemical properties of catalysts were analyzed by using several technique such as X-ray diffraction (XRD), N2-physisorption, SEM-EDX, UV-visible spectroscopy, H2-TPR. Moreover, the …