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Modification Of Screen-Printed Carbon Electrode With Mxene/Conductive Polymer Composites For Hydrogen Peroxide Detection, Supawat Neampet
Modification Of Screen-Printed Carbon Electrode With Mxene/Conductive Polymer Composites For Hydrogen Peroxide Detection, Supawat Neampet
Chulalongkorn University Theses and Dissertations (Chula ETD)
MXene (Ti3C2), a two-dimensional material consisting of transition metal carbides, nitrides or carbonitrides was prepared by etching method for modification electrode of a novel nanocomposites consisting of platinum nanoparticles (PtNPs) and polyaniline (PANI) via electrodeposition and electropolymerization, respectively. The fabricated MXene/PANI/PtNPs nanocomposite modified on surface screen-printed carbon electrode (SPCE) were characterized by scanning electron microscopy SEM) with energy dispersive X-rays spectroscopy (EDX), X-ray powder diffraction (XRD), and transmission electron microscopy (TEM) to verify the presence of nanocomposite materials and indicate their morphologies. This electrode was applied for the detection of hydrogen peroxide (H2O2), which is a common electroactive product from …
Synthesis And Biological Activities Of Halogenated Chalcone-Based Pyra, Dinh Phuoc Nguyen
Synthesis And Biological Activities Of Halogenated Chalcone-Based Pyra, Dinh Phuoc Nguyen
Chulalongkorn University Theses and Dissertations (Chula ETD)
Twenty new 1,3,5-trisubstituted pyrazoline derivatives have been synthesized from chalcones and acylhydrazides in two steps. In the first step, chalcones were prepared by treatment of various acetophenones with different substituted benzaldehydes by Claisen-Schmidt condensation. In the second step, pyrazoline derivatives were synthesized by conducting the reaction of chalcones with acylhydrazides in acetonitrile at 67 °C in the presence of triazabicyclodecene as a catalyst. The synthesized compounds were identified by 1H, 13C NMR and HRMS spectral data and were evaluated for their antibacterial, anticancer and tyrosinase inhibitory activities. In antibacterial and tyrosinase inhibitory activities, most of pyrazoline derivatives showed inactive properties. …
การทูตธุรกิจ : อิทธิพลของบรรษัทข้ามชาติต่อความสัมพันธ์สหรัฐฯ-อินโดนีเซีย 2009 ถึง 2018, ชญานิศวร์ เมธาสิทธิ์รวิกุล
การทูตธุรกิจ : อิทธิพลของบรรษัทข้ามชาติต่อความสัมพันธ์สหรัฐฯ-อินโดนีเซีย 2009 ถึง 2018, ชญานิศวร์ เมธาสิทธิ์รวิกุล
Chulalongkorn University Theses and Dissertations (Chula ETD)
วิทยานิพนธ์ฉบับนี้มีวัตถุประสงค์เพื่อศึกษาอิทธิพลของบรรษัทข้ามชาติอเมริกันต่อการกำหนดนโยบาในประเทศของอินโดนีเซีย และอิทธิพลที่ส่งต่อความสัมพันธ์ระหว่างสหรัฐฯ-อินโดนีเซีย ในช่วงปีค.ศ. 2009-2018 โดยใช้ระเบียบวิธีวิจัยเชิงคุณภาพ ซึ่งสังเคราะห์และวิเคราะห์จากเอกสารราชการของอินโดนีเซียและของสหรัฐอเมริกาที่เผยแพร่ออนไลน์ งานวิชาการด้านเศรษฐกิจการเมืองอินโดนีเซีย ข่าวสารที่เกี่ยวข้อง และข้อมูลบรรษัทที่เข้าไปลงทุน จากการศึกษาพบว่า การที่บรรษัทข้ามชาติอเมริกันเข้ามามีอิทธิพลทางเศรษฐกิจของอินโดนีเซียส่งผลให้บรรษัทข้ามชาติอเมริกันมีบทบาททางการเมืองและสังคมในประเทศอินโดนีเซีย กล่าวคือ การลงทุนของบรรษัทข้ามชาติอเมริกันเป็นส่วนหนึ่งในการพัฒนาความมั่งคั่งทางเศรษฐกิจของอินโดนีเซีย จนทำให้บรรษัทข้ามชาติอเมริกันมีบทบาทสร้างความเจริญเติบโตทางเศรษฐกิจของอินโดนีเซีย ในทางการเมือง บรรษัทข้ามชาติอเมริกันมีบทบาททางการทูตผ่านการรวมกลุ่มเพื่อใช้ในการเจรจากับรัฐบาลอินโดนีเซียเพื่อเสนอข้อตกลง หรือเพื่อเสนอข้อแลกเปลี่ยนผลประโยชน์ระหว่างอินโดนีเซียและบรรษัทข้ามชาติอเมริกัน ในทางหนึ่งอินโดนีเซียเองก็เลือกเจรจากับบรรษัทข้ามชาติอเมริกันเพื่อหาแนวทางสร้างผลประโยชน์ร่วมกัน ในทางสังคม บรรษัทข้ามชาติอเมริกันมีบทบาทในการพัฒนาคุณภาพชีวิตประชาชนอินโดนีเซียผ่านการสร้างความรับผิดชอบต่อสังคม (Corporate Social Responsibility: CSR) จนส่งผลให้บรรษัทข้ามขาติอเมริกันกลายมาเป็นผู้ทำงานร่วมกันกับรัฐบาลอินโดนีเซีย
การพัฒนายุทธศาสตร์การจัดการศึกษาตลอดชีวิตเพื่อส่งเสริมการรู้วิทยาศาสตร์สำหรับพลเมืองของเยาวชนไทย, กรรณิการณ์ เฉิน
การพัฒนายุทธศาสตร์การจัดการศึกษาตลอดชีวิตเพื่อส่งเสริมการรู้วิทยาศาสตร์สำหรับพลเมืองของเยาวชนไทย, กรรณิการณ์ เฉิน
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้มีวัตถุประสงค์เพื่อ 1)สร้างภาพอนาคตของการจัดการศึกษาตลอดชีวิตเพื่อส่งเสริมการรู้วิทยาศาสตร์สำหรับเยาวชนไทย 2) เพื่อพัฒนายุทธศาสตร์การจัดการศึกษาตลอดชีวิตเพื่อส่งเสริมการรู้วิทยาศาสตร์ของเยาวชนไทย ในช่วงระยะเวลา 10 ปีข้างหน้า คือระหว่างปี พศ. 2565-2574 โดยมีกลุ่มเป้าหมายคือเยาวชนอายุระหว่าง 15-24 ปี ทั้งที่อยู่ในการศึกษาในระบบและการศึกษานอกระบบ โดยมีขั้นตอนวิจัย 4 ขั้นตอนคือ 1) การศึกษาแนวคิดและรูปแบบการจัดการศึกษาตลอดชีวิตเพื่อส่งเสริมการรู้วิทยาศาสตร์ของประเทศต่างๆ 2) การศึกษาสภาพการเรียนรู้ตลอดชีวิตด้านวิทยาศาสตร์ และการรู้วิทยาศาสตร์ (Science Literacy) ของเยาวชนในสังคมไทย 3) การจัดทำภาพอนาคตการพัฒนาการศึกษาตลอดชีวิตเพื่อส่งเสริมการรู้วิทยาศาสตร์ (scenario) ด้วยเทคนิควงล้ออนาคต (future wheel) 4)การจัดทำยุทธศาสตร์การจัดการศึกษาตลอดชีวิตเพื่อส่งเสริมการรู้วิทยาศาสตร์เพื่อใช้เป็นข้อเสนอแนะเชิงนโยบายเพื่อใช้ประโยชน์ในหน่วยงานที่เกี่ยวข้องต่อไป ผลการวิจัยพบว่า ได้ภาพอนาคตที่เป็นไปได้สองภาพประกอบด้วย ภาพที่ 1 “สังคมแสนรู้" วิสัยทัศน์ของยุทธศาสตร์ได้แก่ : สังคมที่การจัดการศึกษาและการสร้างองค์ความรู้ใหม่อยู่ในมือของภาคประชาชน หรือชุมชน ซึ่งแรงจูงใจในการเรียนรู้เป็นไปเพื่อการสร้างงาน สร้างอาชีพและเพื่อสรรค์สร้างชุมชนให้เข้มแข็งและเติบโต และมีความสามารถในการเท่าทันสังคมโลก มียุทธศาสตร์ 4 ด้านคือ 1.ส่งเสริมกิจกรรมแบ่งปันความรู้ด้านวิทยาศาสตร์ เทคโนโลยีและนวตกรรมผ่านพื้นที่แลกเปลี่ยนเรียนรู้เพื่อสร้างทักษะและทัศนคติในการพัฒนาองค์ความรู้ใหม่ 2.ส่งเสริมการจัดการศึกษาที่ฝึกกระบวนการแก้ปัญหาและหาคำตอบด้วยการใช้กระบวนการทางวิทยาศาสตร์ 3.พัฒนาระบบฐานข้อมูล วิทยาศาสตร์ เทคโนโลยี และสิ่งแวดล้อมที่ส่งเสริมการเรียนรู้รายบุคคลให้เกิดการเรียนรู้ได้ทุกที่ทุกเวลา ในทุกสาระความรู้ 4.ส่งเสริมการมีส่วนร่วมด้านนโยบายและจริยธรรมวิทยาศาสตร์แก่เยาวชนเพื่อให้เกิดการใช้ความรู้ด้านวิทยาศาสตร์ในชีวิตและสังคม ภาพอนาคตที่ 2 คือ “สังคมสูงวัย อุ่นใจไปด้วยกัน" วิสัยทัศน์ของยุทธศาสตร์คือ : สังคมที่ผู้สูงวัยและเยาวชนอยู่ร่วมกันอย่างเข้าใจ มีความสุข สามารถดูแลซึ่งกันและกันตามศักยภาพของตน รวมทั้งช่วยกันดูแลตนเองและสิ่งแวดล้อมเพื่อให้ทุกคนมีคุณภาพชีวิตที่ดี มีความเท่าทันและยั่งยืน มียุทธศาสตร์ 4 ด้านได้แก่ 1.การจัดการองค์ความรู้ด้านวิทยาศาสตร์สุขภาพและสิ่งแวดล้อมเพื่อรองรับสังคมสูงวัยและสังคมยั่งยืน 2.ส่งเสริมบุคลากรสูงวัยให้เป็นผู้ถ่ายทอดความรู้และภูมิปัญญาด้านวิทยาศาสตร์ เทคโนโลยี และสิ่งแวดล้อม รวมทั้งสุขภาพ สู่ชุมชนและเยาวชน 3.ส่งเสริมการสร้างนวัตกรรมและอาชีพใหม่โดยเยาวชนและผู้สูงวัย เพื่อรองรับสังคมสูงวัยและสังคมยั่งยืน 4.ขยายพื้นที่กิจกรรมวิทยาศาสตร์ 3 วัย เพื่อสร้างโอกาสแลกเปลี่ยนความรู้และมุมมอง สร้างความเข้าใจและความสัมพันธ์อันดีระหว่างเยาวชน วัยทำงานและผู้สูงวัย
Mechanistic Study Of Potential Herbal Extracts For Development Into Hair Growth-Promoting Product, Woraanong Prugsakij
Mechanistic Study Of Potential Herbal Extracts For Development Into Hair Growth-Promoting Product, Woraanong Prugsakij
Chulalongkorn University Theses and Dissertations (Chula ETD)
Androgenic alopecia (AGA) is a major type of hair loss found in both males and females, caused by the overproduction of 5 alpha-dihydrotestosterone (DHT) which is formed from testosterone (T) by the enzymes 5 alpha-reductase (5α-R). In this study, the main focus was on cytokine factors evaluation of Avicennia marina (AM extract) in primary dermal papilla cells (DPCs) from AGA patients and the efficacy in vivo. The present study has revealed that AM extract and its active constituent, avicequinone C (AC) significantly inhibit the enzyme activity of 5α-R on cell-based assay combined with a non-radioactive thin layer chromatography (TLC) using …
Chemosensitizing Effect Of Peptides From Lentinus Squarrosulus On Cisplatin-Induced Apoptosis In Human Lung Cancer Cells, Hnin Ei Ei Khine -
Chemosensitizing Effect Of Peptides From Lentinus Squarrosulus On Cisplatin-Induced Apoptosis In Human Lung Cancer Cells, Hnin Ei Ei Khine -
Chulalongkorn University Theses and Dissertations (Chula ETD)
Cisplatin, platinum-based chemotherapy, is one of the standard chemotherapies for the treatment of lung cancer. However, its usefulness is limited due to the adverse effects and susceptibility to chemoresistance which lead to therapeutic failure. Nowadays, natural chemosensitizers, which can enhance the efficacy and decrease the effective dose of chemo-drugs, have been found to be interested in novel therapeutic. Recently, the anticancer activity of peptides extracted from Lentinus squarrosulus Mont. in human lung cancer cells has been reported. The novel potential of L. squarrosulus peptides as a chemotherapeutic adjuvant to increase cisplatin-induced apoptosis was uncovered in this study. Crude peptides extracted …
Physiological And Immunological Responses Of Porcine Primary Endometrial Cells To Porcine Reproductive And Respiratory Syndrome (Prrs) Virus Infection, Muttarin Lothong
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. …
Production And Purification Of Mannan Oligosaccharide And Its Role In Tight Junction Assembly In Epithelial Cells, Chatchai Nopvichai
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 …
Effect Of Feedback-Resistant Arog Overexpression On L-Phenylalanine Production In Escherichia Coli, Maria Ulfah
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% …
Functional Characterization Of White Spot Syndrome Virus-Responsive Mir-750 In Black Tiger Shrimp Penaeus Monodon, Nichaphat Kanoksinwuttipong
Functional Characterization Of White Spot Syndrome Virus-Responsive Mir-750 In Black Tiger Shrimp Penaeus Monodon, Nichaphat Kanoksinwuttipong
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the RNA interference (RNAi) process, small RNAs called microRNAs (miRNAs) modulate gene expression post-transcriptionally by acting as guides to direct Argonaute (Ago)-containing RNA-induced silencing complexes (RISCs) to targeted mRNAs. The Penaeus monodon miR-750 was previously reported as the highly upregulated miRNA during white spot syndrome virus (WSSV) infection. In this study, the computational program and 2D gel electrophoresis technique were used to identify miR-750 target genes. Bioinformatic analysis suggested that the predicted target mRNAs of miR-750 were ubiquitin-conjugating enzyme E2 Q1 gene (UbcQ1), Actin1 (Act1) and Sarcoplasmic calcium-binding protein (Scp). Furthermore, the alteration of protein expression in the stomach …
Identification And Functional Characterization Of Genes And Micrornas From Penaeus Vannamei In Response To Pathogens And Heat Stress, Pakpoom Boonchuen
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 …
L-Pipecolic Acid Production In Thra Knockout Escherichia Coli, Suttilak Khuanwilai
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 …
Effects Of Mutations Of Levansucrase From Bacillus Licheniformis Rn-01 On Levan Oligosaccharides Binding, Thassanai Sitthiyotha
Effects Of Mutations Of Levansucrase From Bacillus Licheniformis Rn-01 On Levan Oligosaccharides Binding, Thassanai Sitthiyotha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Produced by levansucrase that uses sucrose as a substrate, levan and levan oligosaccharides (GFn) have potential applications in food and pharmaceutical industries such as prebiotics, anti-obesity and anti-tumor agents. Previous study reported that N251A and N251Y mutants of levansucrase from Bacillus licheniformis RN-01 could effectively produce short-chain oligosaccharides upto GF3, instead of long-chain levan synthesis. This study hypothesized that these mutations probably reduced GF3 binding affinity in the active site of levansucrase that contains fructosyl-Asp93 intermediate and caused GF3 to be in an unfavorable orientation for transfructosylation; therefore, levansucrase could not effectively extend GF3 to GF4. However, these mutations probably …
Suppressive Effect Of Crepidatin On Stemness Of Lung Cancer Cells, Narumol Bhummaphan
Suppressive Effect Of Crepidatin On Stemness Of Lung Cancer Cells, Narumol Bhummaphan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Cancer stem cells (CSCs) have been perceived as rare populations driving cancer progression, metastasis, and drug resistance in leading cancers. The discovery of new compounds that attenuates CSCs’ properties is crucial for enabling advances in novel therapeutics to limit recurrence. We have reported the CSC-suppressing activity of chrysotoxine and crepidatin, two bibenzyl compounds isolated from Dendrobium pulchellum. Both chrysotoxine and crepidatin displayed suppression in CSC-like phenotypes, as determined in CSC-rich populations and primary CSCs in 3D culture and extreme limiting dilution assay. Individual treatment of chrysotoxine and crepidatin also affected the expression of CSC markers and associated proteins concomitantly decreased …
Establishment Of An In Vitro System To Screen For Substances To Improve Osteogenesis Imperfecta Osteoblasts Functions, Wandee Udomchaiprasertkul
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: …
Effect Of Major Triterpenoids Of Centella Asiatica On Neurite Outgrowth In Neuro-2a Cells, Nonthaneth Nalinratana
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 …
A Study On The In Vitro Stability And Metabolism Of Curcumin Diethyl Disuccinate In Plasma, Pahweenvaj Ratnatilaka Na Bhuket
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 …
Production Of 1, 12- Dodecanedioic Acid By Recombinant Microbial Cytochrome P450 In Pichia Pastoris And Saccharomyces Cerevisiae, Phawadee Buathong
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 …
Reforming Regulation Of Multi-Level Marketing In Myanmar, Zeyar Nyunt Oo
Reforming Regulation Of Multi-Level Marketing In Myanmar, Zeyar Nyunt Oo
Chulalongkorn University Theses and Dissertations (Chula ETD)
The business of multi-level marketing is prohibited in Myanmar under the Notification no 46/2018. There are not only three paragraphs but also lack of the definition of MLM in this Notification. If distributors sell any product through MLM in Myanmar, they will be punished with imprisonment for a term exceeding three years under section 5 of the Myanmar Essential Goods and Services Law 2012. The study of the provisions on the business of MLM in selected ASEAN countries, Indonesia, Malaysia, Thailand, and Singapore indicates that the definition of multi-level marketing and pyramid scheme is not the same. Moreover, businessman and …
Graphene Sheets Decorated With Silver Nanoparticles As An Oxygen Reduction Reaction Catalyst For Zinc-Air Battery, Laksanaporn Poolnapol
Graphene Sheets Decorated With Silver Nanoparticles As An Oxygen Reduction Reaction Catalyst For Zinc-Air Battery, Laksanaporn Poolnapol
Chulalongkorn University Theses and Dissertations (Chula ETD)
The aim of this thesis is to develop a catalyst for the cathode of a zinc-air battery and to investigate the effects of reduced graphene oxide decorated with silver nanoparticles on the cathode in the zinc-air battery. First, reduced graphene oxide (AgNPs/rGO) was synthesized using glucose reduction at 60 degrees Celsius. Next, the structure and morphology of AgNPs/rGO were checked using X-ray diffraction (XRD). Then, transmission electron microscopy (TEM) analyzes were carried out. The amount of silver (Ag) decorate in graphene oxide was confirmed by EDX. Next, the synthesized catalysts at 3 concentration, using a rotating disk electrode (RDE), led …
Computational Fluid Dynamics Modeling Of The Climate Inside A Chicken House, Nuttaphon Kanjanaudomsuk
Computational Fluid Dynamics Modeling Of The Climate Inside A Chicken House, Nuttaphon Kanjanaudomsuk
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, most of chicken products are from a closed house system. Climate inside such chicken house can significantly affect chicken welfare and its productivity. Moreover, Thailand is in a tropical region where thermal stress is easily occurred. Suitable operating condition and chicken house design can help improve interior climate which can be evaluated by computational fluid dynamics (CFD) modeling technique. In this study, realizable k-ε model, energy conservation and species transport equations were applied to simulate the air velocity, temperature and relative humidity, respectively, inside the chicken house. The model was validated with measured air velocity, temperature and relative humidity …
Dual-Electrolyte System For Suppressing Corrosion Of Aluminum Electrode In Aluminum-Air Flow Battery, Pemika Teabnamang
Dual-Electrolyte System For Suppressing Corrosion Of Aluminum Electrode In Aluminum-Air Flow Battery, Pemika Teabnamang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Aluminum-air batteries have received considerable attention as an electrical power source due to their theoretical specific capacity reaching 2.98 Ah/g. Further, Al-air batteries are abundant and low cost. On the other hand, the aluminum in the batteries has a problem, such that it is subject to self-corrosion in alkaline. Herein, this work concentrates on the aluminum's corrosive behavior and self-corrosion in methanol-3M KOH mixed solution containing different percentages of deionized water i.e. (0, 5, 10 and 20)%wt, using electrochemical (half-cell testing). The aluminum-air battery consists of: aluminum anode | anolyte | anion exchange membrane | catholyte | air cathode. The …
Oxidative Dehydrogenation Of Ethanol To Acetaldehyde Over Magnesium Aluminium Layered Double Hydroxides Catalyst, Piriya Pinthong
Oxidative Dehydrogenation Of Ethanol To Acetaldehyde Over Magnesium Aluminium Layered Double Hydroxides Catalyst, Piriya Pinthong
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, the characteristic and catalytic activity of Mg-Al LDH and their metal-modified mixed oxide were investigated. This research was divided into three parts. In the first part, the effect of calcination temperature on catalytic performance via oxidative dehydrogenation of ethanol was elucidated. The results showed that calcination temperature affected the characteristic of Mg-Al LDH, especially basicity. Moreover, the calcination temperature also affected the catalytic performance on oxidative dehydrogenation of ethanol over Mg-Al LDH. The result was consistent with the basicity of catalysts. In the second part, the Mg-Al mixed oxide derived from calcination of Mg-Al LDH was modified …
Improving The Efficiency Of Dye-Sensitized Solar Cells With Ultrasonic Spray-Coated Tio2 Electrode That Was Modified By Mno2, Coo, Or Sno2, Supasun Thanadvanichkul
Improving The Efficiency Of Dye-Sensitized Solar Cells With Ultrasonic Spray-Coated Tio2 Electrode That Was Modified By Mno2, Coo, Or Sno2, Supasun Thanadvanichkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the modification of TiO2 electrode by adding the second metal oxide, namely, manganese dioxide (MnO2), cobalt oxide (CoO), or tin dioxide (SnO2) use in for dye-sensitized solar cell (DSSCs). TiO2 and modified TiO2 sols were synthesized via sol-gel methods. The sols were sprayed 500 times onto the fluorine-doped tin oxide glass substrates as a thin film using an ultrasonic spray coater. Finally, the thin film electrode was calcined at 400ºC for two hours. The amount of MnO2, CoO, or SnO2 was varied at 0, 0.1, 0.5, 1.0, and 3.0%wt. The photovoltaic efficiency of DSSCs was measured using …
Lactic Acid Production From Glucose By Using Divalent Transition Metal Oxide Catalyst On Magnesium Oxide Support Without Alkaline Solution, Tanyatorn Udomcharoensab
Lactic Acid Production From Glucose By Using Divalent Transition Metal Oxide Catalyst On Magnesium Oxide Support Without Alkaline Solution, Tanyatorn Udomcharoensab
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research was studied the effects of the type of divalent metal oxide (Cu, Co, Ni, and Zn) supported on magnesium oxide catalyst using the hexadecyltrimethylammonium bromide (CTAB) as the capping agent with metal loading at 1.5, 5, and 10 mmol/gram-catalyst on lactic acid production from glucose. To achieve the lactic acid production of lower reactor corrosion rate and being environmentally friendly, the reaction was performed in an alkali additive-free environment. The catalysts were synthesized by hydrothermal method and characterized by various techniques. The XRD pattern of spent CuCTAB/MgO and CoCTAB/MgO catalyst showed the reduced metal species indicated the used …
Computational Fluid Dynamics Of Fluid Transport And Deposition Of Particles Under Unsteady Flow In Human Fluid System, Ratchanon Piemjaiswang
Computational Fluid Dynamics Of Fluid Transport And Deposition Of Particles Under Unsteady Flow In Human Fluid System, Ratchanon Piemjaiswang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Computational fluid dynamics has been widely used to investigate flow phenomena in many different applications. This study focuses on the development of computational fluid dynamic model in biomedical applications, including the flow within human respiratory system and the flow within human circulating system. For the model of respiratory system, electrostatic charge model was coupled, and the effect of breathing frequency was investigated. The accomplishment of the study will gain better understanding of the hydrodynamics when applying the electrostatic field, and will use to identify the potential aerosol deposition location. The aerosol properties and morphologies were also considered their effect on …
Application Of Capillary Electrophoresis For Determination Of Glycosaminoglycans In Biological And Cosmetic Samples, Kanokporn Chindaphan
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 …
Dft And Dftb Investigations On Α–Mangostin Dye Adsorbed On Titanium Dioxide Electrode In Dsscs Application, Kanthira Kaewsud
Dft And Dftb Investigations On Α–Mangostin Dye Adsorbed On Titanium Dioxide Electrode In Dsscs Application, Kanthira Kaewsud
Chulalongkorn University Theses and Dissertations (Chula ETD)
Conformations of α–mangostin dye (1,3,6–Trihydroxy–7–methoxy–2,8–bis(3–methyl–2–buten–1–yl)–9H–xanthen–9–one) were studied and three conformers were found as three co-existing species in various media (in vacuo, acetonitrile and water). Geometries, electronic structures and UV–Vis spectra of all conformers in various media have been obtained using density functional theory (DFT) and time–dependent DFT (TD–DFT) methods. The conformers of α–mangostin dye were inspected as photosensitizers for application in dye sensitized solar cells (DSSCs) and their light–harvesting efficiencies (LHEs) within the range of 0.6757–0.7556 eV (in vacuo), 0.8286–0.8466 eV (in acetonitrile) and 0.8288–0.8465 eV (in water) were obtained. The open circuit voltage (VOC) of three conformers within the …
Green Synthesis Of Gold Nanoparticles Using Wax Leaved Climber Cryptolepis Buchanani Latex And Biological Activities, Kittiphong Tongsuk
Green Synthesis Of Gold Nanoparticles Using Wax Leaved Climber Cryptolepis Buchanani Latex And Biological Activities, Kittiphong Tongsuk
Chulalongkorn University Theses and Dissertations (Chula ETD)
Gold nanoparticles (AuNPs) is the one of nanodrug carriers that have been popular in the current trend. To prepare AuNPs for biomedical applications, many techniques have been developed. However, both physical and chemical methods may cause energy consuming and toxic residues so green synthesis would be the most appropriate method for the preparation of AuNPs. The green synthesis of AuNPs could be provided by utilizing of fungi, bacteria and plant. In this work, we focused to use plant latex as reducing and stabilizing agents for the synthesis of AuNPs. The latex was collected from Cryptolepis buchanani, a folk medicinal plant …
Metalloporphyrin-Sensitized Titania/Silica/Iron Oxide Nanocomposites And Their Photocatalytic Activities, Padtaraporn Chanhom
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 …