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2019

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Co-Expression Of Feedback Resistant Enzymes In Phenylalanine Biosynthesis Pathway To Increase Phenylalanine Production, Charintip Yenyuvadee Jan 2019

Co-Expression Of Feedback Resistant Enzymes In Phenylalanine Biosynthesis Pathway To Increase Phenylalanine Production, Charintip Yenyuvadee

Chulalongkorn University Theses and Dissertations (Chula ETD)

L-Phenylalanine (L-Phe) is an important commercial amino acid. It is widely used in food and pharmaceutical industries. Currently, the requirement of L-Phe is increased according to the great demand for the low-calorie sweetener, aspartame. In Escherichia coli, the synthesis of L-Phe is controlled by the multi-hierarchical regulations. AroG isoform of 3-deoxy- D-arabino-heptulosonate-7-phosphate synthase (DAHP synthase) and chorismate mutase/prephenate dehydratase (PheA), two important enzymes, are feedback inhibited by LPhe. Co-expression of feedback-resistant pheA (pheA[superscript L359D]) with other pivotal genes in L-Phe biosynthesis pathway: aroB, aroL, phedh, tktA, aroG, pheA, yddG, and glpF in pRSFDuet-1 (pPTFBLYA[superscript L359D]) elevated L-Phe production of E. …

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Functional Characterization Of Cytosolic Ddx41 Sensor In Mediating Antiviral Immune Response In Black Tiger Shrimp Penaeus Monodon, Suthinee Soponpong Jan 2019

Functional Characterization Of Cytosolic Ddx41 Sensor In Mediating Antiviral Immune Response In Black Tiger Shrimp Penaeus Monodon, Suthinee Soponpong

Chulalongkorn University Theses and Dissertations (Chula ETD)

DEAD (Asp-Glu-Ala-Asp) box polypeptide 41 (DDX41), a receptor belonging to the DExD family, was recently identified as an intracellular DNA sensor in vertebrates. Here, we investigated the presence of cytosolic DNA sensing, DDX41 in shrimp Penaeus monodon. By searching for gene involved in DNA sensing cascade within the shrimp P. monodon EST database, 3 cDNA fragments exhibited similarity to DDX41 in various species were identified. Sequences assembly resulted in a complete ORF of Penaeus monodon DDX41 (PmDDX41) which has 1868-bp encoding a putative protein of 620 amino acid residues. The multiple sequence alignment of deduced amino acid sequence of PmDDX41 …

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Serial Cultural Heritage Concept, Values Identification, And Management : Case Study Angkor - Phimai Cultural Route, Saowalux Poshyanandana Jan 2019

Serial Cultural Heritage Concept, Values Identification, And Management : Case Study Angkor - Phimai Cultural Route, Saowalux Poshyanandana

Chulalongkorn University Theses and Dissertations (Chula ETD)

Serial cultural heritage refers to groups of cultural heritage sites which are formed as series by significant cultural linkage. It is a category of cultural heritage which has played important roles in World Heritage context, however, it has not been given appropriate attention in general context although it prevails in all cultures. This thesis, therefore, investigated into serial cultural heritage and has clarified its identification, concept, applications, categorization, values identification, and management, both in World Heritage and general contexts, which can be used as initiative frameworks for future works and studies in the issue of serial cultural heritage. To summarize, …

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Fructooligosaccharide Synthesis By Immobilized Inulosucrase From Lactobacillus Reuteri 121 And Improvement Of Product Pattern Using Site-Directed Mutagenesis, Thanapon Charoenwongpaiboon Jan 2019

Fructooligosaccharide Synthesis By Immobilized Inulosucrase From Lactobacillus Reuteri 121 And Improvement Of Product Pattern Using Site-Directed Mutagenesis, Thanapon Charoenwongpaiboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Inulin-type fructooligosaccharides (IFOS) are well-known prebiotics which can be produced from sucrose using bacterial inulosucrase (E.C. 2.4.1.9). However, the use of inulosucrase for IFOS synthesis has some limitations because it also synthesizes some polysaccharides and exhibits lower stability than the fungal enzymes. To overcome these limitations, improvement of inulosucrase was made by using enzyme immobilization and enzyme engineering. First, inulosucrase from Lactobacillus reuteri 121 was immobilized on a novel, high capacity core-shell chitosan beads using glutaraldehyde as a cross-linker. The results showed that both immobilized and free inulosucrase had the same optimum pH (5.5), while the optimum temperature was shifted …

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Reproductive And Developmental Biology Of Rice Field Crab Esanthelphusa Nani (Naiyanetr, 1984), Rachata Maneein Jan 2019

Reproductive And Developmental Biology Of Rice Field Crab Esanthelphusa Nani (Naiyanetr, 1984), Rachata Maneein

Chulalongkorn University Theses and Dissertations (Chula ETD)

The rice field crabs are freshwater crabs that can be considered as pest in paddy field as well as a stable food source by local people. Either of these roles requires a good knowledge of its reproductive biology to manage population in nature. In this study, reproductive and endocrine cycles of male and female, and development of embryo were examined. Adult Esanthelphusa nani were field caught from Nan province during November 2015 to November 2016. Crabs were euthanized and dissected for reproductive tracts. Accessory organ nearby the mandibular muscle was collected for endocrine activities in male, while hemolymph was collected …

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Ecosystem Service Assessment Of Green Roofs In Bangkok, Rattanapan Phoomirat Jan 2019

Ecosystem Service Assessment Of Green Roofs In Bangkok, Rattanapan Phoomirat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Green roofs are constructed ecosystems that can provide four main types of ecosystem services (regulating, provisioning, cultural, and supporting services). However, most green roof studies have focused on the regulating services and each ecosystem service type was usually evaluated separately. Moreover, there is a lack of assessment tool that can provide comparable outputs of total and different ecosystem services on green roofs, resulting in the difficulty to improve ecosystem service provision by green roofs. Therefore, this research aimed to (i) assess four main categories of ecosystem services provided by seven green roofs in Bangkok using direct measurement techniques and a …

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Argonaute 4 Promotes Genomic Methylation, Kanwalat Chalertpet Jan 2019

Argonaute 4 Promotes Genomic Methylation, Kanwalat Chalertpet

Chulalongkorn University Theses and Dissertations (Chula ETD)

RNA-directed DNA methylation (RdDM) is the major small RNA-mediated epigenetic pathway in plants. Similar to genome and epigenome editing with the CRISPR-Cas9 system, RdDM is composed of a regulatory protein and a “guide” RNA (gRNA), which recruits the complex to specific genomic locations containing DNA sequences homologous to the RNA sequence. In humans, we found that Argonaute-4 (AGO4) colocalization has a strong correlation to promoter methylation of AGO4-binding genes. Here, we engineered cell-penetrating tagged oligoarginines (R9) tagged AGO4 (R9-AGO4) or xentry tagged AGO4 (X-AGO4) loaded with single guided-RNA (sgRNA) as a tool to specifically add methylation at genome locations where …

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Serum Non-Coding Rna Levels As Potential Diagnostic And Prognostic Markers Of Hepatocellular Carcinoma, Pornpitra Pratedrat Jan 2019

Serum Non-Coding Rna Levels As Potential Diagnostic And Prognostic Markers Of Hepatocellular Carcinoma, Pornpitra Pratedrat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Hepatocellular carcinoma (HCC) is one of the most common type of liver cancers in the world. Most common cause of HCC is viral hepatitis B infection (HBV). That lead to HCC detection at late stage and be difficult for curative treatment. So, biomarkers for HCC are required to detect HCC efficiently. MicroRNAs and long non-coding RNAs (lncRNAs) play a key role in tumorigenesis through many different mechanisms. Moreover, non-coding RNA can be released into body fluid. Hence purpose of this study is to investigate the level of miRNA and lncRNAs in serum as the used as potential biomarkers for HBV-HCC …

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Ecosystem Function Assessment And Participatory Modelling For Community Forest Management At Lainan Subdistrict, Wiang Sa District, Nan Province, Wuthiwong Wimolsakcharoen Jan 2019

Ecosystem Function Assessment And Participatory Modelling For Community Forest Management At Lainan Subdistrict, Wiang Sa District, Nan Province, Wuthiwong Wimolsakcharoen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Community forest management (CFM) is one way used to mitigate deforestation and forest degradation which have been occurring for more than half a century, particularly in northern Thailand. The collaboration in CFM, especially at multiple scales (e.g. subdistrict, district, or provincial levels) is essential to improve a forest ecosystem status and avoid forest degradation risks in the future. Recently, integrative and participatory modelling methodologies, specifically the Companion Modelling (ComMod), have been implemented in the context of sustainable common-pool resource management in several regions of the world. However, the application of this approach in CFM across institutional scales has still been …

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Role Of Neutrophils In Osteoarthritis And Rheumatoid Arthritis And Their Metabolomics, Dong Zhan Jan 2019

Role Of Neutrophils In Osteoarthritis And Rheumatoid Arthritis And Their Metabolomics, Dong Zhan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Objectives: Fibroblast-like synoviocytes (FLS) plays a function in the development of synovitis in osteoarthritis (OA) and rheumatoid arthritis (RA). Neutrophil-derived microvesicles (NDMV) can protect cartilage and possess anti-inflammatory effects on recipient cells. We investigated the expression of inflammatory cytokines produced by TNFα-stimulated FLS which were pre-treated with NDMV. Methods: FLS isolated from the synovium of patients with OA were characterized by flow cytometry. Neutrophils were isolated from healthy volunteer blood and were characterized by cytospin and flow cytometry. NDMV, generated from TNFα-stimulated neutrophils, were characterized by electron microscopy, nanoparticle tracking analysis and flow cytometry. MicroRNA of NDMV were sequenced by …

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The Effect Of 1’ Acetoxychavicol Acetate On Cell Proliferation, Metastasis, And Angiogenesis In Human Endocrine-Resistant Breast Cancer Cells, Nalinee Pradubyat Jan 2019

The Effect Of 1’ Acetoxychavicol Acetate On Cell Proliferation, Metastasis, And Angiogenesis In Human Endocrine-Resistant Breast Cancer Cells, Nalinee Pradubyat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: Oestrogen receptor (ER)-positive breast cancer patients have a good prognosis, but 30% of these developed resistance through hyperactivation of PI3K/AKT, ERK1/2, and NFκB, which interconnected with ER signalling. In this study, the effects of 1’ acetoxychavicol acetate (ACA), a plant-metabolite acetate ester compound with an NF-kB inhibitory activity, were investigated in a panel of endocrine-resistant breast cancer cells. Methods: Plant material was purified by chromatographic methods and followed by structural identification using nuclear magnetic resonance and mass spectroscopy. In vitro and in vivo antiproliferative effects of ACA were studied in MCF7/LCC2 and MCF7/LCC9 endocrine-resistant cells using the MTT assay …

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Enhanced Propagation Yield Of Influenza Viruses For Vaccine Production Through Cellular Micrornas Regulation, Suthat Saengchoowong Jan 2019

Enhanced Propagation Yield Of Influenza Viruses For Vaccine Production Through Cellular Micrornas Regulation, Suthat Saengchoowong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Annual influenza vaccination aims to prevent influenza virus infection thus reduce the incidence of infection and disease in humans. Nowadays, Madin–Darby canine kidney (MDCK) cell culture-based system has been approved as an alternative for influenza vaccine production. Although cellular microRNAs may play an important role in controlling the replication of viruses, the interaction between human seasonal influenza viruses and host microRNAs has not been investigated in this permissive cell line. The primary objective of this study is to improve the yield of seasonal influenza virus (i.e. vaccine virus) production via manipulation of the host microRNAs. MDCK cells were infected with …

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Angiogenic Effect Of Salt-Leached Thai Silk Fibroin Scaffolds With Human Adipose-Derived Stem Cells, Tanapong Watchararot Jan 2019

Angiogenic Effect Of Salt-Leached Thai Silk Fibroin Scaffolds With Human Adipose-Derived Stem Cells, Tanapong Watchararot

Chulalongkorn University Theses and Dissertations (Chula ETD)

Angiogenesis plays important role in tissue regeneration. Biomaterials that allow and promote angiogenesis are thus beneficial. Silk fibroin (SF) scaffolds are good candidates for angiogenesis activation because of the biodegradability, biocompatibility, and interaction of extracellular matrices. Human adipose-derived stem cells (ADSCs) are also promising for tissue regeneration. This study thus aims to investigate the angiogenic potential of SF scaffolds with/without ADSCs on chick chorioallantoic membrane (CAM). Firstly, the SF scaffolds were fabricated with a porosity of 77.34 ± 16.96% and a pore diameter of 513.95 µm. Then, ADSCs were seeded on SF scaffolds (SF-ADSC scaffolds) and placed on CAM on …

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Antioxidant And Antibacterial Agents From Parmotrema Dilatatum (Vainio) Hale, Knema Angustifolia (Roxb.) Warb. And Persicaria Odorata Lour, Asshaima Paramita Devi Jan 2019

Antioxidant And Antibacterial Agents From Parmotrema Dilatatum (Vainio) Hale, Knema Angustifolia (Roxb.) Warb. And Persicaria Odorata Lour, Asshaima Paramita Devi

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the search of antioxidant and antibacterial agents, the extracts and isolated compounds from lichen Parmotrema dilatatum, Knema angustifolia full name, Persicaria odorata and Mansonia gagei. were examined. Nine compounds were isolated from lichen P. dilatatum including (E)-2,4-dihydroxy-6-methyl-3-(3-oxobut-1-en-1-yl)benzoate (PD.1), hopane-16ß,22-diol (PD.2), methyl orsellinate (PD.3), methyl haemmatomate (PD.4), methyl ß-orcinolcarboxylate (PD.5), 2-hydroxy-4-methoxy-3,6-dimethylbenzoic acid (PD.6), atranol (PD.7), atranorin (PD.8) and lecanorin (PD.9). The dichloromethane and acetone fractions, and atranol (PD.7) gave excellent activities as antioxidants. While in tyrosinase activity the dichloromethane fraction and atranorin (PD.8) showed the highest inhibition. For α-glucosidase inhibition activity, the methanol fraction and methyl haemmatommate (PD.4) revealed the …

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Enhancement Of Biofuel Production In Microalgae By Genetic And Physiological Modification, Napisa Pattharaprachayakul Jan 2019

Enhancement Of Biofuel Production In Microalgae By Genetic And Physiological Modification, Napisa Pattharaprachayakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Microalgae are photosynthetic microorganisms, which could be used as potential microbial cell factories by directly converting CO2 into valuable bioproducts and biofuels. This study aims to improve the target biofuel feedstocks from the isolated green alga Chlorella sp. and the engineered cyanobacterium Synechococcus elongatus PCC 7942 in terms of the improvement on lipids (as precursors of FAMEs) and terpene (α-farnesene), respectively. The first part is concerned with the enhancement of lipids and the determination of FAMEs and biodiesel properties in Chlorella sp. under the phosphorus (P) limitation (0-50%) alone or in combination with heavy metals (Fe, Co, Pb) supplementation. The …

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Binding Kinetics Of Monoclonal Antibodies And Fluoroquinolone Derivatives, Patamalai Boonserm Jan 2019

Binding Kinetics Of Monoclonal Antibodies And Fluoroquinolone Derivatives, Patamalai Boonserm

Chulalongkorn University Theses and Dissertations (Chula ETD)

Fluoroquinolones (FQs) are a group of antibiotics which have been extensively used against both Gram-negative and Gram-positive bacteria. Some of FQs antibiotics commonly used in livestock and fishery include norfloxacin, enrofloxacin, ciprofloxacin, and ofloxacin. However, misuse of these antibiotics may cause drug residues in food products. Therefore, to prevent consumers from getting residual antibiotics in food and the drug resistance of pathogens in humans. As a result, surveillance detection program of these drug residues must be in practice to ensure safety of the consumers in many countries. In general, detections based on immunological method include enzyme-linked immunosorbent assay (ELISA) has …

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Screening And Identification Of Probiotic Lactic Acid Bacteria From Plant Samplesd, Ratthanatda Nuhwa Jan 2019

Screening And Identification Of Probiotic Lactic Acid Bacteria From Plant Samplesd, Ratthanatda Nuhwa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Seventy lactic acid bacteria (LAB) were isolated from flowers (17 strains), 3 tree barks (7 strains), one fruit (2 strains), ten fermented tea leaves (31 strains) and two silage (13 strains). They were identified as Lactobacillus pentosus (12 strains), L. plantarum subsp. plantarum (9 strains), L. paracasei subsp. tolerans (5 strains), L. brevis (1 strain), L. silagincola (1 strain), L. kunkeei (1 strain), and L. formosensis (1 strain), Enterococcus durans (3 strains), E. lactis (2 strains), E. faecalis (1 strain), E. faecium (1 strain), E. gallinarum (1 strain) and E. gilvus (1 strain), Pediococcus acidilactici (1 strain) and P. pentosaceus …

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Development Of Oxidase Enzyme And Non-Enzyme Based Biosensors For Lactate And Creatinine Detection, Siraprapa Boobphahom Jan 2019

Development Of Oxidase Enzyme And Non-Enzyme Based Biosensors For Lactate And Creatinine Detection, Siraprapa Boobphahom

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation focused on the development of electrochemical sensors based on metal oxides and graphene modified electrodes for clinical applications, which is divided into two parts. The first part is development of a biosensor based on lactate oxidase (LOx) immobilized on titanium dioxide sol (TiO2 sol)/graphene nanocomposite modified nickel (Ni) foam electrode for enzymatic electrochemical detection of lactate via hydrogen peroxide (H2O2) detection. A TiO2/graphene nanocomposite was simply synthesized by hydrolysis and coated on Ni foam electrode to develop a novel electrode in biosensor. The results showed that the well intercalation of TiO2 sol within graphene film covered on the …

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Role Of Enzymes In Glyoxylate Cycle In Transgenic 'Kdml 105' Rice Oryza Sativa L. Overexpressing Oscam1-1 Under Salt Stress, Tanaporn Ausaha Jan 2019

Role Of Enzymes In Glyoxylate Cycle In Transgenic 'Kdml 105' Rice Oryza Sativa L. Overexpressing Oscam1-1 Under Salt Stress, Tanaporn Ausaha

Chulalongkorn University Theses and Dissertations (Chula ETD)

The previous study reported that the transcriptome profiling of the KDML 105 rice overexpressing OsCam1-1 widely affected the expression of genes involved in several cellular processes including the genes associated with the glyoxylate cycle, which exhibited up-regulation in KDML 105 overexpressing OsCam1-1 under salt stress. In this study, we focused on the role of the glyoxylate cycle in transgenic KDML 105 rice under salt stress. The phenotypes as follows: fresh weight and dry weight of shoot & root, SPAD value, activities of isocitrate lyase, and malate synthase; sugar, and starch contents, and total lipid content were investigated at 0, 2, …

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Marketing Strategy Development For Professional Services Firms: Case Study Of Certified Audit Firms In Russia, Dmitrii Bushkov Jan 2019

Marketing Strategy Development For Professional Services Firms: Case Study Of Certified Audit Firms In Russia, Dmitrii Bushkov

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work is devoted to developing a strategy based on the Blue Ocean Strategy framework for audit firms in Russia. Today, audit firms in Russia are in an awkward position, caused by a fall of revenue in real terms, a high level of competition and a difficult economic situation. Therefore, audit firms are forced to look for new ways to grow their business. The paper analyzes the market for audit services in the period from 2009 to 2018, including structural analysis, revenue analysis, and assessment of the impact of the largest audit firms on the market. The historical background shows …

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Legal Analysis On Bankability Of Hydro Floating Solar Project In Thailand, Natdanai Aramtiantamrong Jan 2019

Legal Analysis On Bankability Of Hydro Floating Solar Project In Thailand, Natdanai Aramtiantamrong

Chulalongkorn University Theses and Dissertations (Chula ETD)

In comparison to other types of renewable energy projects, hydro floating solar projects are more complicated as public water resources are used as the location of the project but the electricity is generated from solar power. Accordingly, it is unclear whether the operation of the project falls within the definition of water use that is subject to the Water Resources Act B.E.2561(2018) or not. Several interpretations on the definition of water use in Section 4 of this Act may cause challenges in the bankability of the project. In order to fund the project, the project company generally relies on the …

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The Experience Of The Application Of Safeguards On Certain Iron Or Steel Products In Indonesia : Lesson For Thailand, Nattanit Santimetvirul Jan 2019

The Experience Of The Application Of Safeguards On Certain Iron Or Steel Products In Indonesia : Lesson For Thailand, Nattanit Santimetvirul

Chulalongkorn University Theses and Dissertations (Chula ETD)

In comparison to other trade remedies under WTO, the number of safeguard measures imposed by WTO members has been relatively low as the requirements of safeguard is difficult to fulfill. However, there is change to such trend as there has been an increase in number of safeguard measures imposed by Indonesia. The Appellate Body Report on Indonesia — Safeguard on Certain Iron or Steel Products has provided important lesson to Thailand concerning on the determination of safeguard measure which has not been clearly mentioned in the WTO cases. The importance of safeguard characterization has been emphasized. This dispute has given …

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B2c Online Dispute Resolution (Odr) Legal Frameworkfor Myanmar, Nwe Ni Htun Jan 2019

B2c Online Dispute Resolution (Odr) Legal Frameworkfor Myanmar, Nwe Ni Htun

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis examines the applicability of ODR mechanism for consumer disputes in Myanmar especially cross-border disputes. The paper consists of introduction; three main parts and a conclusion. The effect is the appearance of ODR and understanding of what is meant by ODR, how it works and why ODR is needed for consumer. It concludes the review of ODR by both information and communication technology (ICT) and legal view. The paper focuses on case study analysis and compares the legal framework; institutions based on the problem analysis form each case of ODR in the EU and Myanmar. Moreover why use ODR …

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Challenges Of Excise Tax Reform In Myanmar : Illegal Alcohol Market And Method Of Charging On Alcoholic Beverages, Ngu Wah Maung Jan 2019

Challenges Of Excise Tax Reform In Myanmar : Illegal Alcohol Market And Method Of Charging On Alcoholic Beverages, Ngu Wah Maung

Chulalongkorn University Theses and Dissertations (Chula ETD)

Myanmar excise tax system is started from the British colonial regime. Excise tax system of Myanmar is complex and different from the other country. Myanmar excise tax system was reformed in several times. Before 2016, alcohol tax was collected as commercial tax. In 2016, the Specific Goods Tax Law was enacted and excise tax for alcoholic beverages has been named as specific goods tax under this law. According to this law excise tax was collected as specific goods tax. Reducing the alcohol consumption is one of the purposes of this law. This thesis analyses weaknesses of Myanmar excise tax system …

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Ethanol Dehydration Over Wo3/Tio2 Catalysts Using Titania Derived From Sol-Gel And Solvothermal Methods With Palladium Modification, Anchale Tresatayawed Jan 2019

Ethanol Dehydration Over Wo3/Tio2 Catalysts Using Titania Derived From Sol-Gel And Solvothermal Methods With Palladium Modification, Anchale Tresatayawed

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, the characteristics and catalytic activity of WO3/TiO2 prepared by sol-gel and solvothermal and their metal modified were investigated. The research was divided into two parts. In the first part, the catalyst performance of WO3/TiO2 catalysts using titania derived from sol-gel and solvothermal methods over ethanol dehydration reaction was examined. The results showed that the different preparation methods essentially altered the physicochemical properties of TiO2 supports. It revealed that the titania derived from solvothermal method denoted as TiO2-SV exhibited higher surface area and pore volume, and larger amounts acid sites than the one obtained from sol-gel method (TiO2-SG). …

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Development Of Bioplastic Blown Films To Be Used As A Packaging For Dried Banana, Apinya Wongthanaroj Jan 2019

Development Of Bioplastic Blown Films To Be Used As A Packaging For Dried Banana, Apinya Wongthanaroj

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aimed to study effects of poly(butylene adipate-co-terephthalate) (PBAT) contents on properties of polylactic acid / poly(hydroxybutyrate-co-hydroxyvalerate) / poly (butylene adipate-co-terephthalate) (PLA/PHBV/PBAT) blends to be used as a packaging for solar-dried bananas. The blend of PLA and PHBV (PLA/PHBV) was fixed at weight ratio of 80/20 while the PBAT content was varied from 0-30 wt%. The films were prepared by melt compounding and blown film extrusion. It was found that the addition of PBAT decreased barrier properties of PLA/PHBV film. Gas barrier which is oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) increased with increasing of PBAT …

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Production Of Activated Carbonaceous Catalyst For Their Application In Bio Jet-Fuel Synthesis, Araya Smuthkochorn Jan 2019

Production Of Activated Carbonaceous Catalyst For Their Application In Bio Jet-Fuel Synthesis, Araya Smuthkochorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Recently, research and development in alternative aviation fuel to replace fossil-based fuel has been of interest for many research works. Hydrodeoxygenation (HDO) is one of the most efficient processes to produce clean fuel. This study involves the synthesis of activated carbon (AC) from heavy fuel oil (HFO) via the carbonization-chemical activation process for utilization as catalyst support. AC with a high surface area of 1527.4 m2/g was obtained from KOH-activation in the ratio of 1:1 and carbonization temperature of 700°C. The molybdenum phosphide (MoP) catalyst impregnated on AC was prepared via the wet impregnation process. The microscopic analysis revealed the …

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Solar Energy Management System For Stand-Alone Application : Analysis Of Power Management Strategies Under Different Solar Irradiance Profiles, Chacrit Lerdwithayaprasit Jan 2019

Solar Energy Management System For Stand-Alone Application : Analysis Of Power Management Strategies Under Different Solar Irradiance Profiles, Chacrit Lerdwithayaprasit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Clean power generation from various renewable energy sources has been gaining much attention due to sustainable and environmental reasons. As renewable energy sources and power demand vary, a hybrid power system and proper energy management are required. This study is focused on the development of an energy management system (EMS) in the hybrid renewable energy system consisting of photovoltaic cell (PV), proton exchange membrane fuel cell (PEMFC), and proton exchange membrane electrolysis cell (PEMEC). A vanadium redox flow battery (VRFB) as energy storage for long-term operation is integrated into such a hybrid system. The models of each subsystem are developed …

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Co-Electrodeposition Of Gold Nanoparticle And Reduced-Graphene Oxide In Application Of Achetylcholinesterase Biosensor, Chiranthanin Mahayotheecharak Jan 2019

Co-Electrodeposition Of Gold Nanoparticle And Reduced-Graphene Oxide In Application Of Achetylcholinesterase Biosensor, Chiranthanin Mahayotheecharak

Chulalongkorn University Theses and Dissertations (Chula ETD)

A rapid pesticide detection technique is highly desirable due to the widespread usage of many pesticides in the agricultural industry. An emerging technique that shows promising potential is an electrochemical biosensor. The technique allows sensitive and rapid quantification of an analyte. Due to its simplicity, it could be a potential alternative to traditional method. In this work, we utilised a composite materials consist of partially reduced graphene oxide (rGO) and gold nanoparticle (AuNPs) to fabricate a disposable AChE biosensor on a Screen-Print Carbon electrode. The composite rGO and AuNPs possess high electron conductivity while AuNPs also exhibit desirable biocompatibility. The …

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Mechanism And Reaction Pathways Of Co2 And Hco3-Photoreduction To Hydrocarbons, Duangthip Sattayamuk Jan 2019

Mechanism And Reaction Pathways Of Co2 And Hco3-Photoreduction To Hydrocarbons, Duangthip Sattayamuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

CO2/HCO3- photocatalytic reductions in water, using P25 Titanium dioxide, produce gas products at the order of the following rate: CO>H2>CH4, using bicarbonate as a substrate, reduction rates are ca. 5 times faster than using CO2 due to the adsorption constant of CO2 on the TiO2 surface is smaller than the bicarbonate. Langmuir-Hinshelwood kinetic model was used to describe the mechanism; therefore, adsorption constant (K) and the rate of maximum substrate coverage (k) at different charges of P25-surface were readily obtained. The K constant of TiO2-adduct formation favors no charge surface but k constant favors positive charge surface. Most …

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