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2017

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3d Printing Of Graphene/Thermoplastic Elastomer Composites, Warrayut Kanabenja Jan 2017

3d Printing Of Graphene/Thermoplastic Elastomer Composites, Warrayut Kanabenja

Chulalongkorn University Theses and Dissertations (Chula ETD)

Graphene based thermoplastic polyurethane composites filaments was prepared by melt blending process prior to fabricate with 3D printing technique. The effects of different graphene loading (0.05 wt% - 0.20 wt%) in TPU matrix on the properties of composites were studied. Initially, graphite was successfully oxidized to graphite oxide following Hummer’s method and the reduction of graphene oxide to graphene by L-ascorbic acid was also achieved as being confirmed by the FTIR and XRD results. TPU and TPU/graphene nanocomposites were investigated for their thermal, mechanical, physical and electrical properties. Thermal stability of TPU/graphene composites was improved against neat TPU. The first …

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Revitalizing Tio Chew Chinese Cemetery Through A Design Of An Elderly Center, Khai Sin Lee Jan 2017

Revitalizing Tio Chew Chinese Cemetery Through A Design Of An Elderly Center, Khai Sin Lee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Old cemeteries are often threatened by new urban development, which can result in them being closed, relocated or demolished. This thesis studies Tio Chew Cemetery in Bangkok as an alternative case based on its current unique use as a recreation area. Although without the threats of demolition, several on-site issues, both tangible and intangible, are facing Tio Chew Cemetery. To respond to these issues, a design of an elderly center is proposed to improve and revitalize the cemetery through the understanding of historical importance and contemporary design of new buildings in the old compound. This research applies a mixed methodology …

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Tropical Strategy Of Modern Architecture In Cambodia For The Design Of A Contemporary Art Space In Phnom Penh, Pisith Ty Jan 2017

Tropical Strategy Of Modern Architecture In Cambodia For The Design Of A Contemporary Art Space In Phnom Penh, Pisith Ty

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the past decades, Cambodia has experienced a boom in building construction. However, many of those buildings do not take sustainable approach into account. They are built without concern of the tropical climate which results into a high level of energy consumption from air-conditioning system. Some none-commercial buildings, such as cultural and educational facilities, could not be operated because of lack of the fund for electricity. For a better understanding of architectural design in the tropical environment of the context, the research focuses on the works of Vann Molyvann, the father of architects in Cambodia, a state architect in 1960s, …

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Expression And Characterization Of Α-Glucosidase From Weissella Confusa Bbk-1, Lalita Silapasom Jan 2017

Expression And Characterization Of Α-Glucosidase From Weissella Confusa Bbk-1, Lalita Silapasom

Chulalongkorn University Theses and Dissertations (Chula ETD)

Alpha-glucosidase [EC 3.2.1.20; α-D-glucoside glucohydrolase] is an exohydrolase which catalyzes non-reducing end of substrates to release D-glucose. In addition, alpha-glucosidase also displays a transferase activity, which bring about the formation of α-glucosylated compounds such as soluble starch and glycogen. This research aims to express and characterize α-glucosidase from Weissella confusa BBK-1 (WcAG). WcAG gene was expressed in modified pET28b vector. This gene contained an open reading frame of 1,775 bps. Optimum expression condition of WcAG was cultured in LB medium containing 1% (w/v) glucose and induced with 0.4 mM IPTG at 20°C for 20 h. The recombinant WcAG containing his-tag …

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Isolation And Characterization Of Triclocarban Degrading Bacteria As Plant Growth Promoter, Merry Krisdawati Sipahutar Jan 2017

Isolation And Characterization Of Triclocarban Degrading Bacteria As Plant Growth Promoter, Merry Krisdawati Sipahutar

Chulalongkorn University Theses and Dissertations (Chula ETD)

Triclocarban (TCC) is a widely used as antimicrobial agent in household products. High usage volume of TCC results in its accumulation in sludge and lead to contamination in environments. Application of biosolid in agricultural activities leads to contamination of TCC in agricultural areas. So. development of bioremediation technique for TCC is necessary to maintain quality of agricultural ecosystem. For that purpose, this research isolated 5 soil bacteria capable of TCC degradation and with plant-growth promoting (PGP) activities including Ochrobactrum sp. MC22, Ochrobactrum sp. MC35, Sphingobacterium sp. MC43, Pseudomonas sp. MS45, and Pseudomonas fluorescens MC46. Among them, Ochrobactrum sp. MC22 and …

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Effects Of Curcumin-Loaded Bacterial Cellulose Films On Cancer Cells, Chayut Subtaweesin Jan 2017

Effects Of Curcumin-Loaded Bacterial Cellulose Films On Cancer Cells, Chayut Subtaweesin

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, a curcumin-loaded bacterial cellulose films were developed. Bacterial cellulose films were prepared by culturing Gluconacetobacter xylinus in coconut water-based medium. Curcumin, an active substance found in turmeric (Curcuma longa Linn), was then absorbed into never-dried bacterial cellulose pellicles by immersion in 0.5 and 1.0 mg/ml curcumin solutions, with absolute ethanol as solvent, for 24 hours. The curcumin-loaded bacterial cellulose pellicles were then air-dried. Controlled release of curcumin was achieved in buffer solutions containing Tween 80 and methanol additives, at pH 5.5 and 7.4. Curcumin-loaded bacterial cellulose films prepared with curcumin solutions at concentrations of 0.5 and 1.0 …

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Prevalence And Molacular Genetic Analysis Of Human Respiratory Syncytial Virus And Enterovirus 68 Among Children With Acute Lower Respiratory Tract Infection In Thailand, I-Lada Thongpan Jan 2017

Prevalence And Molacular Genetic Analysis Of Human Respiratory Syncytial Virus And Enterovirus 68 Among Children With Acute Lower Respiratory Tract Infection In Thailand, I-Lada Thongpan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Respiratory syncytial virus (RSV) causes acute lower respiratory tract infection in infants and young children worldwide. A clear description of local RSV molecular epidemiology, evolution, and transmission requires detailed sequence data and can inform new strategies for virus control and vaccine development. To investigate the RSV burden in Thailand over six consecutive years (January 2012 to December 2017). There were two different methods to detect RSV in the present study. First, we screened 3306 samples obtained from children ≤5 years old with acute respiratory tract infection using semi-nested reverse-transcription polymerase chain reaction (RT-PCR) during January 2012 to December 2015. Second, …

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Pathomechanism Of X-Linked Osteogenesis Imperfecta, Siraprapa Tongkobpetch Jan 2017

Pathomechanism Of X-Linked Osteogenesis Imperfecta, Siraprapa Tongkobpetch

Chulalongkorn University Theses and Dissertations (Chula ETD)

Osteogenesis imperfecta (OI) or brittle bone disease is a genetic disorder characterized by deformities of bones and multiple bone fractures. We identified a new causative gene, MBTPS2, in two unrelated patients with OI inherited in X-linked pattern (X-OI). MBTPS2 or site-2 protease (S2P) is a protease that cleaves the transmembrane proteins to activate them acting as transcription factors. To determine pathomechanism of X-OI caused by MBTPS2 mutations, S2P functions were investigated. RNA and protein of S2P were stable. Instead, the defective S2P decreases its cleavage activities. ATF6 and CREB3L1 are target proteins of S2P. We demonstrated decreased a transcriptional activity …

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Isoquinoline Alkaloid Composition And Expression Of Biosynthetic Genes In Mechanically Wounded Sacred Lotus, Thitirat Meelaph Jan 2017

Isoquinoline Alkaloid Composition And Expression Of Biosynthetic Genes In Mechanically Wounded Sacred Lotus, Thitirat Meelaph

Chulalongkorn University Theses and Dissertations (Chula ETD)

Isoquinoline alkaloids, a plant secondary metabolites present in many plant species including lotus (Nelumbo nucifera Gaertn.). Lotus leaf contains high amount of bioactive nuciferine and N-nornuciferine. A set of enzyme including NCS, 6OMT and CNMT and WRKY transcription factors (WRKY TFs) has been reported to have corresponding function in the biosynthesis isoquinoline alkaloids. Thus, we performed quantitative analysis on expression level of these corresponing genes and on nuciferine and N-nornuciferine content in lotus leaf using mechanical wounding method. Sequence analysis clearly showed that all the targeted genes possess the conserved region belongs to their protein families. The accumulation of compound …

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Effects Of Mitragynine On Morphine And Methamphetamine Addiction In Animal Models Of Addiction, Rittinarong Meepong Jan 2017

Effects Of Mitragynine On Morphine And Methamphetamine Addiction In Animal Models Of Addiction, Rittinarong Meepong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Kratom (Mitragyna speciosa Korth) has long been used in folklore medicine in Southeast Asian countries. It has been used for its analgesic effects and treatment of opioid withdrawal. Mitragynine is a major alkaloid found in the leaves of kratom plant that exerts its effects via activation of opioid receptors and other receptors in the central nervous system. This study aimed to provide evaluation of abuse liability and potential of mitragynine in the treatment for opioids and amphetamine type stimulants addictions. Abuse liability of mitragynine and its effects on morphine and methamphetamine addiction were evaluated by drug discrimination, conditioned place preference …

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Bioactive Peptide Derived From Trypsin Hydrolysis Of Unicellular Cyanobacterium Synechococcus Sp., Rutairat Suttisuwan Jan 2017

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.

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Antibacterial Agents From Dracaena Cochinchinensis (Lour.) S.C.Chen And Eleutherine Americana (Aubl.) Merr. Ex K. Heyne, Ritbey Ruga Jan 2017

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 …

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Adaptation Of Terrilactibacillus Laevilacticus Sk5-6 For Growth And D-Lactic Acid Production In A Low Yeast Extract Concentration Medium, Srettapat Limsampancharoen Jan 2017

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 …

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Tyrosinase Inhibitors From Bark Of Talawrinta (Manilkara Kauki (L.) Dubard, Sirinada Srisupap Jan 2017

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, …

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Increasing Viability Of Probiotic Bacteria Co-Encapsulated With Prebiotic For Disease Resistance In White Shrimp Litopenaeus Vannamei, Suppharada Jantarathin Jan 2017

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, …

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Optimization Of Preparation Protein Hydrolysate By Protease G6 Using Response Surface Methodology And Free Radical Scavenging Activities From Feather Meal, Waleeporn Pibulpol Jan 2017

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 …

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Optimization Of D-Lactic Acid Production By Terrilactibacillus Laevilacticus Sk5-6 And Fermentation Process Scale Up In 30 Litre-Fermentor, Woraphot Toliang Jan 2017

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 …

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Malfunctioned Pacemaker And Business Operator's Liability In Us, Eu And Australia: Implication For Thailand, Peerasak Ounhachoke Jan 2017

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 …

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Legal Measures For Employer To Reach Fair Practice In Organizational Restructuring In Thailand, Pitsanuchai Thongtha Jan 2017

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 …

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Effects Of Pbs Quantum Dot Doped Tio2 Nanotubes As Electron Transporting Layer On The Efficiency Of Perovskite Solar Cells, Natthapat Rattanawichai Jan 2017

Effects Of Pbs Quantum Dot Doped Tio2 Nanotubes As Electron Transporting Layer On The Efficiency Of Perovskite Solar Cells, Natthapat Rattanawichai

Chulalongkorn University Theses and Dissertations (Chula ETD)

TiO2 nanotubes (TNTs) are used as an excellent electron transporting layer for high efficiency perovskite solar cells. In this work, TNTs were synthesized via hydrothermal process from different particle sizes of TiO2 nanoparticle precursors as follows: 5 nm, 25 nm, and 50 nm. The highest surface area of 312.39 m2/g of TNTs was obtained from TiO2 precursor with particle size of 25 nm and was used to dope with lead sulfide quantum dots (PbS QDs). Due to a large band gap and poor conductivity of TNTs which limits the efficiency to transport electrons in the perovskite solar cell, PbS QDs …

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Preparation Of Stable Hydrothermal Carbon-Based Catalyst From Defatted Rice Bran And Glucose For Biomass Conversion To 5-Hydroxymethylfurfural, Piyaporn Wataniyakul Jan 2017

Preparation Of Stable Hydrothermal Carbon-Based Catalyst From Defatted Rice Bran And Glucose For Biomass Conversion To 5-Hydroxymethylfurfural, Piyaporn Wataniyakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research investigated the preparation of hydrothermal carbon-based catalysts (HTC-SO3H) derived from defatted rice bran (DRB) and glucose for biomass conversion to 5-hydroxymethylfurfural (HMF). Firstly, the effects of hydrothermal carbonization conditions: temperature (180-250 °C) and time (1-8 h) on the yield and the chemical characteristics of the hydrothermal carbons (HTCs) were investigated. The HTCs were then sulfonated with sulfuric acid to obtain HTC-SO3H catalysts. The stability of the catalysts was evaluated based on the amount of biomass conversion products leached into the water at a specified biomass conversion condition. Since no HMF and furfural, and only small amounts of levulinic …

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The Effect Of Adsorption On Photocatalytic Degradation Of Phenyl Urea Herbicides On Zinc Oxide, Sutaporn Meephon Jan 2017

The Effect Of Adsorption On Photocatalytic Degradation Of Phenyl Urea Herbicides On Zinc Oxide, Sutaporn Meephon

Chulalongkorn University Theses and Dissertations (Chula ETD)

The effect of adsorption on photocatalytic degradation was studied by using zinc oxide with different morphologies and exposed surfaces as the photocatalyst. Polar zinc-terminated surface and polar oxygen-terminated surface are dominating planes on the top and bottom of a crystal of ZnO conventional particles, while non-polar surface is the main plane on the side of ZnO nanorods. These surfaces affect the adsorption behavior of phenylurea herbicides, i.e. diuron, linuron and 3,4-dichloroaniline. Consequently, they cause the difference in photocatalytic degradation rate and intermediate products formed during the degradation. The adsorption capacity of ZnO conventional particles is about twice as high as …

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Effect Of Operating Variables Of Corona Discharge Reactor Onbenzene Removal Efficiency, Thanunwut Thanahirunthitichote Jan 2017

Effect Of Operating Variables Of Corona Discharge Reactor Onbenzene Removal Efficiency, Thanunwut Thanahirunthitichote

Chulalongkorn University Theses and Dissertations (Chula ETD)

Volatile organic compound (VOC) has been known as one of air pollutants generated by the fast growth of industry and social development. There were many kind of VOC which is harmful for humans and environments. All concerned organization requested controlling of these problems. As a result, there were many technologies developed for handling and degrading such VOC. Among these technologies, corona discharge reactor has been known as a promising means because of its effectiveness and compactness. In this work, benzene was selected as a model VOC pollutant. Performance of multi-channeled corona discharge reactor for removal of benzene was experimentally examined …

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Chromatographic Separation Of Free Lutein And Fatty Acids In De-Esterified Marigold Oleoresin And Its Mathematical Modelling, Weerawat Clowutimon Jan 2017

Chromatographic Separation Of Free Lutein And Fatty Acids In De-Esterified Marigold Oleoresin And Its Mathematical Modelling, Weerawat Clowutimon

Chulalongkorn University Theses and Dissertations (Chula ETD)

The petal of marigold flowers has been reported to be the richest source of a xanthophyll, namely lutein which exhibits strong antioxidant and anticancer properties. Although large amount of lutein can be obtained, the compound in the flowers exists as esterified lutein, which is not readily bio-available. As a result, a number of separation and purification steps are required after solvent extraction of marigold flowers. One of the key steps is de-esterification of lutein fatty acid esters in the extract, or namely marigold oleoresin, by the reaction of the oleoresin with alkali solution, e.g., KOH, to obtain free lutein. The …

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Application Of Headspace-Gas Chromatography-Mass Spectrometry For Characterization Of Volatile Compounds In Chicken Eggs, Hanan Jehma Jan 2017

Application Of Headspace-Gas Chromatography-Mass Spectrometry For Characterization Of Volatile Compounds In Chicken Eggs, Hanan Jehma

Chulalongkorn University Theses and Dissertations (Chula ETD)

Volatile compounds in chicken eggs under the cold chain system and non-cold chain system were characterized by headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with chemometrics. According to a central composite design, the following optimum HS-SPME extraction conditions were obtained: extraction temperature of 65 oC, extraction time of 45 min and the amount of NaCl of 0.4 g. In comparison of their mass spectrum and linear retention index from HS-SPME-GC-MS analysis, major volatile compounds found in egg samples included toluene, hexanal, nonanal and other minor volatile compounds were heptanal, octanal, decanal, benzaldehyde, 1-octen-3-ol and 2-ethyl-1-hexanol, with the types and amounts …

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Adsorption Of Paraquat Herbicide In Water Using Humic Acids Supported On Sludge From Tap Water Production Entrapped In Alginate Beads, Munlika Suksai Jan 2017

Adsorption Of Paraquat Herbicide In Water Using Humic Acids Supported On Sludge From Tap Water Production Entrapped In Alginate Beads, Munlika Suksai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Adsorption of paraquat in water using humic acids supported on sludge from tap water production or alum sludge entrapped in alginate beads has been studied. The adsorbent was characterized by Fourier transform infrared spectroscopy showing that it composes of humic acids, alum sludge and alginate in beads. Afterwards, the type and amount of adsorbents were studied including bare alginate beads, humic acids-alginate beads, alum sludge-alginate beads, alum sludge-humic acids-alginate beads-1 and alum sludge-humic acids-alginate beads-2. These adsorbents were subjected to the paraquat adsorption study in aqueous solutions. The results showed that all adsorbents can adsorb paraquat, especially the alum sludge-humic …

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Characterization Of Aroma-Active Volatile Compounds In Tom Yum Soup By Gas Chromatography-Mass Spectrometry Combined With Sensory Evaluation Techniques, Pannipa Janta Jan 2017

Characterization Of Aroma-Active Volatile Compounds In Tom Yum Soup By Gas Chromatography-Mass Spectrometry Combined With Sensory Evaluation Techniques, Pannipa Janta

Chulalongkorn University Theses and Dissertations (Chula ETD)

Gas chromatography-mass spectrometry/olfactometry coupled with headspace-solid phase microextraction (HS-SPME-GC-O/MS) was applied for the characterization of volatile compounds in Tom Yum soup and its individual ingredients including lemongrass, kaffir lime leaf, chili, fish sauce and lime juice. Using HS-SPME with a 50/30 µm DVB/CAR/PDMS fiber and an extraction temperature of 40 °C for 50 min, along with an HP-5MS capillary column programmed from 50 to 200 °C at 3 °C/min and an MS electron impact ionization at -70 eV, 101 peaks in the HS-SPME-GC-MS chromatogram of Tom Yum soup were detected, and 96 volatile compounds were identified including alcohols, aldehydes, esters, …

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Colorimetric Detection Of Cyanide Ions Using Complex Formation And Ctab-Coated Silica, Patita Salee Jan 2017

Colorimetric Detection Of Cyanide Ions Using Complex Formation And Ctab-Coated Silica, Patita Salee

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research presents a new colorimetric method of cyanide detection in solution and water samples based on the extraction of dicyano-bis-(1,10-phenanthroline)-iron(II) complex onto CTAB-coated silica. The complex was formed at pH 10 by using phosphate buffer via the complex formation between tris-(1,10-phenanthroline)-Iron(II) (ferroin) with cyanide ions in CTAB media. When the complex was extracted onto CTAB-coated silica, it resulted in a color change of the material from pale yellow to purple. The changing of color corresponded to cyanide concentration which could be observed by naked-eyes and the color intensity was determined by Image J. The effects of various parameters were …

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Fabrication Of Silver Nanofilament Based On Silver Sulfide Solid Electrolyte For Tip-Enhanced Raman Spectroscopy, Phichaya Fueaimi Jan 2017

Fabrication Of Silver Nanofilament Based On Silver Sulfide Solid Electrolyte For Tip-Enhanced Raman Spectroscopy, Phichaya Fueaimi

Chulalongkorn University Theses and Dissertations (Chula ETD)

Surface science analysis is the crucial fundamental of nanoscale study. The techniques combined morphological and compositional study on the surface are the promising technique. Tip-enhanced Raman spectroscopy (TERS) is the coupling of atomic force microscopy (AFM) and Raman spectroscopy which give the 3D- images and bonding information in ambient conditions. Furthermore, TERS tip is an ideal tool for the high enhancement and spatial resolution. Nowadays, TERS tip fabrication is still challenged. There are three main challenges that are high enhancement factor of the TERS tip, reproducibility of the tip and in-depth understanding of TERS process. We introduce the simple method …

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Fluoride Encapsulation In Calcium Matrix, Piyada Dissara Jan 2017

Fluoride Encapsulation In Calcium Matrix, Piyada Dissara

Chulalongkorn University Theses and Dissertations (Chula ETD)

Fluoride ion (F-) is an important ingredient in a toothpaste. It protects caries by reacting with hydroxyapatite [Ca10(PO)4(OH)2] in tooth enamel to form insoluble fluorapatite [Ca10(PO)4(F)2]. Unfortunately, F- also easily interacts with calcium species in a toothpaste, and then it is deactivated. In this work, we focus on the encapsulation of F- in a shellac bead by using a simple extrusion method. To construct shellac beads, an aqueous solution of F- is injected into an ethanolic solution of shellac. The shellac beads are formed due to insolubility of shellac in water. Then, the beads are transferred into DI water for …

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