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2018

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Articles 22831 - 22860 of 23961

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Synthetic Snake Venom: The Novel Creation Of Crotalid Phospholipase A2 Using Genetic Engineering, Taylor Anderson, Emily Jesgarz, Richard Klein, Andrew Merkley, Alaric Siddoway Jan 2018

Synthetic Snake Venom: The Novel Creation Of Crotalid Phospholipase A2 Using Genetic Engineering, Taylor Anderson, Emily Jesgarz, Richard Klein, Andrew Merkley, Alaric Siddoway

Biological Engineering

Antivenin is listed as one of the World Health Organization’s Essential Medicines1, and as such, it is integral to a modern health care system. Antivenin is currently developed through a process of milking venomous animals, in this case, snakes, concentrating the venom, inoculating animals, and isolating antibodies found in their plasma. The aim of this project is to genetically engineer an organism to overexpress common proteins found in snake venom, thereby lowering the cost of antivenin.

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Senate Blue Slips And Senate Regular Order, Carl Tobias Jan 2018

Senate Blue Slips And Senate Regular Order, Carl Tobias

Law Faculty Publications

Justice Neil Gorsuch’s Supreme Court confirmation process exacerbated the striking divisiveness, rampant partisanship, and stunning paybacks that have systematically plagued the federal judicial selection process. The Senate basically ended any true debate when the Republican majority peremptorily detonated the “nuclear option” for Supreme Court nominees. This measure limited filibusters regarding all judicial nominees, allowing a simple majority ballot to confirm a nominee. One century-long practice that does remain is the “blue slip.” Under Senate tradition, whenever the President submits a federal district or appeals court nominee, the Judiciary Committee Chair sends a blue slip of paper to each senator who …

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Physiological And Immunological Responses Of Porcine Primary Endometrial Cells To Porcine Reproductive And Respiratory Syndrome (Prrs) Virus Infection, Muttarin Lothong Jan 2018

Physiological And Immunological Responses Of Porcine Primary Endometrial Cells To Porcine Reproductive And Respiratory Syndrome (Prrs) Virus Infection, Muttarin Lothong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Porcine reproductive and respiratory syndrome virus (PRRSV) is highly limited to only cell subsets that express PRRSV receptors. Reproductive organ revealing the typical signs of PRRSV infection may be the critical site of problem syndromes. Persistent PRRSV producing re-infection via horizontal or vertical transmission could not be eradicated from herds. This research examined the possibility of porcine endometrium to be a PRRSV permissive cell and serves as the primary cause of the persistent PRRSV. Cellular and immunological in response to PRRSV relevant to viral replication, shedding and re-circulation was assessed. The different outcomes between the different genotypes (type I vs. …

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Production And Purification Of Mannan Oligosaccharide And Its Role In Tight Junction Assembly In Epithelial Cells, Chatchai Nopvichai Jan 2018

Production And Purification Of Mannan Oligosaccharide And Its Role In Tight Junction Assembly In Epithelial Cells, Chatchai Nopvichai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mannan Oligosaccharide (MOS) is well-known as prebiotic supplement that help increasing life quality of livestocks and animals. Many reports revealed that MOS supplement can help improve intestinal morphology, enhancing growth performance, raising body weight, and increasing metabolic and stress response. MOS feeding also affected several biological processes in peripheral blood mononuclear cells in pigs and modulates expression of many immune-related genes that helps to prevent and reduce the severity of viral infection. However, the mechanism of action of MOS is remained unclear and the production, purification, identification of bioactive MOS molecular type is needed. In this study, we developed a …

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Effect Of Feedback-Resistant Arog Overexpression On L-Phenylalanine Production In Escherichia Coli, Maria Ulfah Jan 2018

Effect Of Feedback-Resistant Arog Overexpression On L-Phenylalanine Production In Escherichia Coli, Maria Ulfah

Chulalongkorn University Theses and Dissertations (Chula ETD)

L-Phenylalanine (L-Phe) is one of the most important amino acids in food and pharmaceutical industries. It is widely used as a nutritional supplement and a precursor for the synthesis of food additives. The market of L-Phe has been stimulated by increasing demand for the low-calorie sweetener, aspartame. In Escherichia coli, the key enzyme which catalyzes the first committed step of aromatic amino acid biosynthesis pathway is 3-deoxy-D-arabino-heptulosonate-7- phosphate synthase (DAHP-synthase). The enzyme has 3 isoforms, AroG, AroF and AroH, which are feedback inhibited by L-Phe, L-Tyr and L-Trp, respectively. AroG, encoded by aroG, is the major isoform contributed about 80% …

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Identification And Functional Characterization Of Genes And Micrornas From Penaeus Vannamei In Response To Pathogens And Heat Stress, Pakpoom Boonchuen Jan 2018

Identification And Functional Characterization Of Genes And Micrornas From Penaeus Vannamei In Response To Pathogens And Heat Stress, Pakpoom Boonchuen

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the present day, high-throughput (HT) sequencing techniques provide in-depth data on how the transcripts are expressed and regulated and in this case shed light on how innate immunity responds to different stimuli. Acute Hepatopancreatic Necrosis Disease (AHPND) caused by Vibrio parahaemolyticusproducing Pir toxin (VPAHPND) is a current severe bacterial disease in shrimp. Suppression subtractive hybridization (SSH) was used to identify differentially expressed genes (DEGs) in hepatopancreas and hemocyte of VPAHPND-challengedPenaeus vannamei. The hemocyaninand Vago5 were found as up-regulated genes in hepatopancreas and hemocyte of VPAHPND-infectedP. vannamei, respectively. Their functions in shrimp immunity against VPAHPNDinfection were then characterized. The native …

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L-Pipecolic Acid Production In Thra Knockout Escherichia Coli, Suttilak Khuanwilai Jan 2018

L-Pipecolic Acid Production In Thra Knockout Escherichia Coli, Suttilak Khuanwilai

Chulalongkorn University Theses and Dissertations (Chula ETD)

L-pipecolic acid (L-PA) is a non-proteinogenic amino acid, however, it is an important precursor and a key ingredient of many pharmaceutically compound syntheses such as immunosuppressants and anesthetics. The production of amino acids via fermentation of microorganisms are getting attention, one of the widely used is an engineered E. coli. L-PA production in the engineered E. coli uses L-lysine in its cell as a substrate. This research aimed to increase L-PA production by thrA knockout. The thrA encodes homoserine dehydrogenase I, the enzyme which draws the intermediate in L-lysine biosynthesis pathway to synthesize L-threonine. The group II intron insertion was …

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Functional Characterization Of Inhibitor Of Kappa B Kinase In Black Tiger Shrimp Penaeus Monodon Antiviral Signaling Pathway, Zittipong Nhnhkorn Jan 2018

Functional Characterization Of Inhibitor Of Kappa B Kinase In Black Tiger Shrimp Penaeus Monodon Antiviral Signaling Pathway, Zittipong Nhnhkorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

The IKK-NF-κB signaling cascade is one of the crucial responsive mechanisms in inflammatory and immune responses. The key kinase proteins called inhibitor of kappa B kinases (IKKs) serve as the core elements involved in cascade activation. Here, the complete open reading frames of IKK homologs including PmIKKβ, PmIKKε1 and PmIKKε2, from the black tiger shrimp Penaeus monodon were identified and characterized for their functions in shrimp antiviral responses. The PmIKK transcripts were widely expressed in various examined tissues and the PmIKKε protein was detected in all three types of shrimp hemocytes. Only the PmIKKε1 and PmIKKε2 were responsive to white …

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Mutation Identification And Functional Analysis Of Mutant Dax-1 Proteins Found In Thai Patients With X-Linked Adrenal Hypoplasia Congenita, Chanisara Suthiworachai Jan 2018

Mutation Identification And Functional Analysis Of Mutant Dax-1 Proteins Found In Thai Patients With X-Linked Adrenal Hypoplasia Congenita, Chanisara Suthiworachai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mutations in the DAX-1 gene result in X-linked adrenal hypoplasia congenita (X-linked AHC), a rare congenital disorder of adrenal insufficiency with defects in adrenal gland development and steroid biosynthesis. Male patients usually develop severe adrenal insufficiency in early infancy or childhood. In some cases, hypogonadotropic hypogonadonism (HH) is presented in puberty. DAX-1 gene product, DAX-1 protein, acts as a transcriptional repressor of genes in the steroidogenic pathway by interacting with, and repressing the steroidogenic factor 1 (SF-1) protein. In contrast, the SF-1 protein transactivates the steroidogenic acute regulatory (StAR) protein that functions in the steroid biosynthetic pathway. The aim of …

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Effects Of Habitat Enhancement On Bird Diversity In Kaeng Khoi District, Saraburi Province, Dijan Sunar Rukmi Jan 2018

Effects Of Habitat Enhancement On Bird Diversity In Kaeng Khoi District, Saraburi Province, Dijan Sunar Rukmi

Chulalongkorn University Theses and Dissertations (Chula ETD)

Various techniques of habitat enhancement have been used to increase the habitat quality, consequently enriching biodiversity and maintaining ecosystem services. This study aims to assess the effects of habitat enhancement on bird diversity, guild composition and bird usage pattern by conducting bird censuses and observations as well as arthropod samplings in the landscape-scale (LS) experiment plots and in the teak reforestation (TR) enhanced with sunflower and sunn hemp species over dry and wet seasons of 2015-2016. Sunflower treatment attracted more bird species (LS: 28, TR: 19) than sunn hemp treatment (LS: 25, TR: 15), but bird occurrence was varied based …

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Taxonomy And Systematics Of Earthworm Genus Pontodrilus Perrier, 1874 In Thailand, Teerapong Seesamut Jan 2018

Taxonomy And Systematics Of Earthworm Genus Pontodrilus Perrier, 1874 In Thailand, Teerapong Seesamut

Chulalongkorn University Theses and Dissertations (Chula ETD)

A taxonomic study of the littoral earthworm genus Pontodrilus Perrier, 1874 was critically conducted based on material collected from marine sandy coasts along the east and west sides of the Thai-Malay Peninsula (Thailand and Malaysia) and selected localities in Japan. Comparative material from other parts of Southeast Asia, including Myanmar, Vietnam, Malaysia, Singapore and Indonesia, were also collected. Morphological examination identified almost all of the specimens as Pontodrilus litoralis, but as two morphotypes with some character differences in the diverticulum between them. A combined morphological and molecular phylogenetic analyses supported one of these morphotypes as a new species, P. longissimus. …

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The Role Of Cytokine Response Signatures In The Pathogenesis Of Leptospirosis Associated Acute Kidney Injury, Nattachai Srisawat Jan 2018

The Role Of Cytokine Response Signatures In The Pathogenesis Of Leptospirosis Associated Acute Kidney Injury, Nattachai Srisawat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: Acute Kidney Injury (AKI) is one of the most serious complications of leptospirosis, an important zoonosis in the tropics. Host pathogen interaction is one of the potential key factor in development of leptospirosis associated AKI. In this multicenter study, we aimed to study the association of cytokines, leptospiral burden, and anti-leptospira antibody and AKI in leptospirosis. Method: In the first cohort, patients who presented with clinical suspiciousness of leptospirosis were prospectively enrolled in 9 centers from August 2012 to November 2014. In the second cohort, we prospectively recruited patients from 15 centers from February 2016 to July 2017. The …

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Molecular Epidemiology And Characterization Of Rotavirus Group A, Group C And Porcine Epidemic Diarrhea Virus In Pigs With Gastroenteritis Among The Commercial Swine Farms In Thailand, 2011-2016, Supansa Tuanthap Jan 2018

Molecular Epidemiology And Characterization Of Rotavirus Group A, Group C And Porcine Epidemic Diarrhea Virus In Pigs With Gastroenteritis Among The Commercial Swine Farms In Thailand, 2011-2016, Supansa Tuanthap

Chulalongkorn University Theses and Dissertations (Chula ETD)

The most frequent viruses associated with pig gastroenteritis have been previously reported as porcine epidemic diarrhea virus (PEDV) and rotavirus (RV). Rotavirus is an important cause of diarrhea in piglets and pigs worldwide, and group A (RVA) and group C (RVC) are mostly affected. In Thailand, studies on RVA and PEDV have been reported periodically, whereas information on RVC is still limited. In this study, 769 samples (fecal and intestinal content) from pigs with diarrhea were collected from pig herds located in difference provinces throughout Thailand between 2011 and 2016. The specimens were tested using virus-specific RT-PCR to detect the …

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Establishment Of An In Vitro System To Screen For Substances To Improve Osteogenesis Imperfecta Osteoblasts’ Functions, Wandee Udomchaiprasertkul Jan 2018

Establishment Of An In Vitro System To Screen For Substances To Improve Osteogenesis Imperfecta Osteoblasts’ Functions, Wandee Udomchaiprasertkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: Osteogenesis imperfecta (OI) is a heritable bone disorder caused mainly by dominant mutations in genes encoding collagen-related proteins which are COL1A1 and COL1A2. Genotype-phenotype correlation has some discrepancies which lead to the difficult prediction of the clinical outcome of OI patients. We identified a child with dentinogenesis imperfecta (DI) and OI who was homozygous for c.1009G>A (p.G337S) mutation in COL1A2. Her parents were heterozygous for the mutation and had only DI. This family provides the opportunity to explore the biochemical changes which are different between the homozygous with DI and OI and the heterozygous with DI only. Methods: …

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Immunity To Pertussis Vaccination, Nasamon Wanlapakorn Jan 2018

Immunity To Pertussis Vaccination, Nasamon Wanlapakorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Thailand has implemented universal whole cell pertussis vaccination in children for more than 35 years; nevertheless, the numbers of reported pertussis cases are still on the rise, especially among infants below one year who bear the greatest risk of severe complications. Several countries have implemented a pertussis booster during adolescence. However, data on the appropriate age groups targeted for a booster in the Thai population is limited. The increase in pertussis incidence among Thai infants warrants the need to further investigate the pre-existing maternal antibody against Bordetella pertussis (B. pertussis) antigens and the potential benefit of Tetanus toxoid-reduced dose of …

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Effect Of Major Triterpenoids Of Centella Asiatica On Neurite Outgrowth In Neuro-2a Cells, Nonthaneth Nalinratana Jan 2018

Effect Of Major Triterpenoids Of Centella Asiatica On Neurite Outgrowth In Neuro-2a Cells, Nonthaneth Nalinratana

Chulalongkorn University Theses and Dissertations (Chula ETD)

Centella asiatica has been reported to demonstrate neuroprotection and memory improvement in various animal models. Triterpenoid glycosides, madecassoside (MS), asiaticoside (AS), and their aglycones, madecassic acid (MA) and asiatic acid (AA) are considered as major neuroactive constituents in C. asiatica. In this study we aimed to compared MS, AS, MA and AA for their neurite outgrowth activities and mechanisms in Neuro-2a cells. Immunofluorescent staining against ßIII-tubulin showed that MS and AS significantly increased the percentage of neurite-bearing cells and neurite length with higher potency than MA and AA. Our mechanistic studies revealed the differences in signal activation between glycosides and …

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A Study On The In Vitro Stability And Metabolism Of Curcumin Diethyl Disuccinate In Plasma, Pahweenvaj Ratnatilaka Na Bhuket Jan 2018

A Study On The In Vitro Stability And Metabolism Of Curcumin Diethyl Disuccinate In Plasma, Pahweenvaj Ratnatilaka Na Bhuket

Chulalongkorn University Theses and Dissertations (Chula ETD)

Stability in aqueous media such as buffers and plasma are the one of important properties of drug candidates. Curcumin diethyl disuccinate (CDD), an ester prodrug of curcumin, has been developed to improve the chemical stability of curcumin. In this study, the in vitro stability of CDD in HCl buffer (pH 1.2), acetate buffer (pH 4.5), phosphate buffer (pH 6.8, 7.4 and 8.0) and in vitro metabolism of CDD in rat, dog and human plasma were investigated at 4, 25 and 37 °C. HPLC and nonlinear regression analyses showed that the degradation of CDD in buffers was temperature-dependent and followed pseudo-1st …

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Optimization Of Protein Hydrolysate Preparation From Split Gill Mushroom Schizophyllum Commune, Aunchalee Wongaem Jan 2018

Optimization Of Protein Hydrolysate Preparation From Split Gill Mushroom Schizophyllum Commune, Aunchalee Wongaem

Chulalongkorn University Theses and Dissertations (Chula ETD)

The optimum conditions for hydrolysate production from split gill mushroom protein using the microbial protease, Alcalase were investigated. The study was conducted using central composite design and response surface methodology. Three independent factors: hydrolysis temperature (45, 50, and 55 °C); hydrolysis time (60, 120, and 180 min); and enzyme to substrate ratio (2%, 4%, and 6% w/v) were varied, while the pH was fixed at pH 8. These three factors had a significant effect on the DH and ABTS radical-scavenging activity (p < 0.05). The optimum conditions obtained from experiments were: enzyme to substrate ratio 2%; hydrolysis time 161.4 min; and temperature 55 °C. The coefficient of determination (R2) of total protein and the IC50 value for ABTS radical-scavenging activity were 0.972 and 0.205 µg/mL, respectively, and the DH value was 50.882%. The hydrolysate was fractionated by molecular weight (MW) cut-off membranes (10, 5, 3, and 0.65 kDa). The < 0.65 kDa fraction had the highest radical scavenging ability (IC50 = 0.026 ± 0.004 µg/mL). The MW < 0.65 kDa fraction was separated by reversed-phase HPLC to yield four subfractions (F1–5). The F4 subfraction showed the highest maximum ABTS radical-scavenging activity and was selected for further analysis by quadrupole-time-of-flight-electron spin induction–mass spectrometry-based. Five antioxidant peptides were identified. In addition, the MW< 0.65 kDa fraction protected against oxidation-induced DNA damage in pBR322, pKS, and pUC19 plasmids. Furthermore, the MW < 0.65 kDa fraction, exhibited cellular antioxidant activity in a human intestinal cancer cell line (HT-29), which was dependent on the peptide concentration. These results suggested that split gill mushroom protein hydrolysate is a good source of bioactive peptides and has potential as a natural antioxidant in food production and cosmetic products.

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Production Of 1, 12- Dodecanedioic Acid By Recombinant Microbial Cytochrome P450 In Pichia Pastoris And Saccharomyces Cerevisiae, Phawadee Buathong Jan 2018

Production Of 1, 12- Dodecanedioic Acid By Recombinant Microbial Cytochrome P450 In Pichia Pastoris And Saccharomyces Cerevisiae, Phawadee Buathong

Chulalongkorn University Theses and Dissertations (Chula ETD)

1,12-Dodecanedioic acid (DDA) is a primary compound which is used as an intermediate precursor for production of valuable chemical products. Biosynthesis of 1,12-DDA by recombinant (r) microorganisms can be used as an alternative method to compensate several disadvantages from chemical synthesis. The purpose of this study was to clone a CYP52A17 from Candida tropicalis to produce cytochrome P450 which can terminally oxidize fatty acids to hydroxy-fatty acids and further to dicarboxylic acids (ω-oxidation). The wild type rCYP52A17 and its engineered L261S/L490S (leucine changed to encode for serine) form (rCYP52A17mut) were expressed in Pichia pastoris and Saccharomyces cerevisiae which coexpressing the …

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Optimization Of Protein Hydrolysate Preparation And Their Angiotensin I-Converting Enzyme Inhibitory Activity From Shiitake Mushrooms Lentinula Sp., Supawee Paisansak Jan 2018

Optimization Of Protein Hydrolysate Preparation And Their Angiotensin I-Converting Enzyme Inhibitory Activity From Shiitake Mushrooms Lentinula Sp., Supawee Paisansak

Chulalongkorn University Theses and Dissertations (Chula ETD)

Angiotensin-I converting enzyme (ACE) is a key enzyme involved in regulating blood pressure. ACE converts angiotensin-I into angiotensin-II, which results in raised blood pressure. Inhibition of ACE leads to a decreased concentration of angiotensin-II and lowering of blood pressure. Food protein-derived ACE inhibitory peptides are considered to be a safer alternative to antihypertensive drugs. Shiitake mushrooms, one of the most consumed mushrooms in Thailand, are recognized as a nutritive food with health-stimulating properties. The aim of this study was to optimize the preparation of a shiitake-protein hydrolysate and investigate the ACE inhibitory activity of the hydrosylate. Shiitake mushrooms were hydrolyzed …

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Flowering Phenology And Pollination Biology Of Ceropegia Thailandica Meve And Ceropegia Suddeei Kidyoo, Chayanin Kraithep Jan 2018

Flowering Phenology And Pollination Biology Of Ceropegia Thailandica Meve And Ceropegia Suddeei Kidyoo, Chayanin Kraithep

Chulalongkorn University Theses and Dissertations (Chula ETD)

The flowers of the genus Ceropegia have complex structures that involve in pollination mechanism. These structres gynostegium, pollinarium and corona. Moreover, the corolla tube which is inflated at base and the corolla lobes are connate only at tip forming a cage-like structure functions as a trap. When pollinators are attracted to flower, they could be temporarily trapped inside the flower. From previous studies, there are about 18 species in Thailand. Most Thai species have flowers characterized by a long narrow corolla lobe with distinct inflated basal portion. However, some species have a short corolla tube, such as C. thailandica Meve. …

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Taxonomic Revision And Pollination Biology Of Orchid Genera Crepidium Blume And Dienia Lindl. (Malaxidinae, Orchidaceae) In Thailand, Anchalee Nuammee Jan 2018

Taxonomic Revision And Pollination Biology Of Orchid Genera Crepidium Blume And Dienia Lindl. (Malaxidinae, Orchidaceae) In Thailand, Anchalee Nuammee

Chulalongkorn University Theses and Dissertations (Chula ETD)

The terrestrial orchid Crepidium Blume and Dienia Lindl. in Thailand were enumerated by Gunnar Seidenfaden under Malaxis with key and drawings. Because of no species descriptions in publication, it is difficult to delimit species boundary. Moreover, recent discovery of new species results in unreliable assessment of species, therefore, the taxonomic revision of Crepidium and Dienia in Thailand should be carried out. The results indicated that the column and transversal callus on labellum are taxonomically important characters to delimit these two genera. In addition, morphological characters, i.e. stem and leaf morphology, labellum auricles, margins and number of teeth on distal margin …

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Simulation Of Water Effect On Biodiesel Production Using Waste Cooking Oil Via Ester-Transesterification In A Reactive Distillation Column, Ajala Anantapinitwatna Jan 2018

Simulation Of Water Effect On Biodiesel Production Using Waste Cooking Oil Via Ester-Transesterification In A Reactive Distillation Column, Ajala Anantapinitwatna

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research investigated the effect of water content in waste cooking oil (WCO) on the performance of a reactive distillation column for biodiesel production via ester-transesterification. A mixture of triolein and oleic acid was used as a WCO model compound. Amberlyst-15 was used to catalyze esterification while CaO was used for transesterification. From Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model taking into account water absorption for esterification of oleic acid (FFA), biodiesel yield was decreased with increasing of water content in WCO feedstocks. On the other hand, the initial rate of transesterification was increased with increase of amount of water in WCO feedstocks …

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Synthesis Of Activated Carbons From Coffee Ground Residues And Their Application As Catalysts For Ethanol Dehydrogenation, Jeerati Ob-Eye Jan 2018

Synthesis Of Activated Carbons From Coffee Ground Residues And Their Application As Catalysts For Ethanol Dehydrogenation, Jeerati Ob-Eye

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this present study, characteristics and catalytic properties of activated carbon derived from coffee ground residue, cobalt metal (Co) supported-activated carbon and various metals (Ce, Co, Cu and Ni) supported-commercial activated carbon were determined and characterized. This study was divided into three parts. Regarding to the first part, the synthesis of activated carbon catalysts derived from coffee ground residues with different methods of physical activation was investigated. The results showed that the catalyst with physically activated by CO2 for 4 hours, exhibited the best catalytic activity of ethanol dehydrogenation to acetaldehyde. In the second part, the best catalyst from the …

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Hydrothermal Carbonization Carbon-Based Acid Catalyst For Biodiesel Production, Laddawan Tumkot Jan 2018

Hydrothermal Carbonization Carbon-Based Acid Catalyst For Biodiesel Production, Laddawan Tumkot

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aims to synthesize the production of biodiesel (oleic acid methyl ester) by esterification in the presence of sulfonated hydrothermal carbon based catalyst under microwave irradiation. The catalyst was prepared by hydrothermal carbonization, followed by sulfonation presenting sulfonic acid group as an active site. The catalyst characterization results confirmed good microwave-absorptivity of the catalyst which can be heated directly and accelerate the reaction immediately at the surface of the catalyst. Esterification of oleic acid (OA) with methanol experiments were optimized by using response surface methodology based on central composite design. Three variables: molar ratio of methanol to OA (2.5:1-7.5:1), …

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

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

Chulalongkorn University Theses and Dissertations (Chula ETD)

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

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

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

Chulalongkorn University Theses and Dissertations (Chula ETD)

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

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

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

Chulalongkorn University Theses and Dissertations (Chula ETD)

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

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Application Of Capillary Electrophoresis For Determination Of Glycosaminoglycans In Biological And Cosmetic Samples, Kanokporn Chindaphan Jan 2018

Application Of Capillary Electrophoresis For Determination Of Glycosaminoglycans In Biological And Cosmetic Samples, Kanokporn Chindaphan

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, on-line preconcentration and determination of glycosaminoglycans (GAGs), especially chondroitin sulfate (CS), dermatan sulfate (DS) and hyaluronic acid (HA) using capillary electrophoresis (CE) was developed. Large-volume sample stacking using an electroosmotic flow (EOF) pump (LVSEP) technique was employed for on-line preconcentration and improvement of the detection sensitivity in CE method. Central composite design (CCD) was used to simultaneously optimize all parameters for CE separation. The optimized CE conditions were background electrolyte consisting of 200 mM sodium dihydrogen phosphate, 200 mM buthylamine and 0.5% w/v polyethylene glycol at pH 4.0 and separation voltage of -16 kV. Limit of detections …

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Metalloporphyrin-Sensitized Titania/Silica/Iron Oxide Nanocomposites And Their Photocatalytic Activities, Padtaraporn Chanhom Jan 2018

Metalloporphyrin-Sensitized Titania/Silica/Iron Oxide Nanocomposites And Their Photocatalytic Activities, Padtaraporn Chanhom

Chulalongkorn University Theses and Dissertations (Chula ETD)

New nanomaterials of the magnetic visible light active photocatalysts, tetra(4-carboxyphenyl)porphyrin (TCPP) with different metals [Mn(II), Fe(III), Cu(II), Zn(II) and metal-free] in the center adsorbed on titania-silica-iron oxide superparamagnetic composites (TSI) were synthesized successfully. The photocatalytic activities in methylene blue (MB) degradation were determined under incandescent lamp for 3 h. Their characteristics have been identified using UV-visible spectroscopy, X-ray diffractometry (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The photodegradation results revealed that the metalloporphyrin sensitization helped TSI to absorb the light in visible region. Titania-silica-iron oxide nanomaterials with copper(II) tetra(4-carboxyphenyl)porphyrin (CuTCPP) can significantly …

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