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Articles 1741 - 1770 of 1777
Full-Text Articles in Chemistry
Detection Of Nitrite By Thread-Based And Paper-Based Devices By Modified Griess Reagent, Pitcha Singhaphan
Detection Of Nitrite By Thread-Based And Paper-Based Devices By Modified Griess Reagent, Pitcha Singhaphan
Chulalongkorn University Theses and Dissertations (Chula ETD)
New thread-based and paper-based devices for the determination of nitrite ions based on modified Griess reagent were developed. The surface of the materials was chemically modified with p-aminobenzoyl moiety and chromotropic acid was used as a coupling reagent. The functionalization of the materials was confirmed by Raman spectroscopy. By using the thread-based device, the detection of nitrite was achieved by measuring the color band length. The optimum concentration of chromotropic acid was 5 mM in 0.10 M sulfuric acid mixed with 0.2 M citric acid. The working range was from 50 to 1,000 µM with a sample volume of 15 …
Detection Of Cyanide Ions Using Chemosensing Ensembles Under Indicator Displacement Assays, Ratanakorn Teerasarunyanon
Detection Of Cyanide Ions Using Chemosensing Ensembles Under Indicator Displacement Assays, Ratanakorn Teerasarunyanon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Anion recognition is an attractive area of research in recent decades as anions play an important role in a wide range of chemical, biological, and environmental processes. This dissertation reports three projects dedicated to anion recognition with applications in fluoride and cyanide sensing. The first project of the dissertation describes the chemistry of two novel anthracene derivatives bearing one and two dimesitylboryl substituents (compounds 1 and 2, respectively) for the complexation of anions. All investigations provide insights into the electronic structure and effect of fluoride and cyanide binding. The results demonstrate that these boranes have a high affinity for fluoride …
Development Of Paper-Based Colorimetric Sensor For Determination Of Human Papillomavirus Dna, Sarida Naorungroj
Development Of Paper-Based Colorimetric Sensor For Determination Of Human Papillomavirus Dna, Sarida Naorungroj
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this work, a paper-based analytical device (PAD) based on colorimetric assay using pyrrolidinyl peptide nucleic acid (acpcPNA) probe was developed as a sensor for the detection of Human papillomavirus (HPV) DNA. Dextrin-stabilized gold nanoparticles (d-AuNPs) was employed as a colorimetric reagent. The aggregation of d-AuNPs can be induced by positively charged acpcPNA generating a distinctive color change. After the hybridization of acpcPNA and DNA target, the residual acpcPNA probe can cause different degrees of the d-AuNPs aggregation, resulting in the detectable color change. The different color change before and after the introduction of the DNA target as a function …
Optimization Of Enantiomeric Separation By Gas Chromatography Using Beta-Cyclodextrin Derivatives As Stationary Phases, Suchada Muangsri
Optimization Of Enantiomeric Separation By Gas Chromatography Using Beta-Cyclodextrin Derivatives As Stationary Phases, Suchada Muangsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Enantiomeric separations of seventy-two underivatized chiral alcohols and forty-three trifluoroacetyl derivatives of chiral amines of various structures were investigated by gas chromatography using two types of cyclodextrin-based chiral stationary phases: heptakis(2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-beta-CD (or BSiAc) and heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl)-beta-CD (or BSiMe). Each compound was analyzed by temperature program and the optimum isothermal condition for each compound was also determined. It was found that resolution and elution temperature obtained from a temperature program run could be used as a guideline for quickly determining the optimum isothermal condition for enantiomeric separation. For a 15-meter long capillary column, if a resolution less than 1.0 was obtained, a …
Development Of Fluorinated Rhodacyanine Analogues For Anti-Leishmaniasis, Thitiya Lasing
Development Of Fluorinated Rhodacyanine Analogues For Anti-Leishmaniasis, Thitiya Lasing
Chulalongkorn University Theses and Dissertations (Chula ETD)
Recently, fluorinated rhodacyanine has been disclosed as a highly effective agent against Leishmania donovani; it was shown that replacement of hydrogen with a fluorine atom on a benzothiazole unit significantly enhanced the anti-leishmanial activity. However, the role of the fluorine substituent in this analogue has not yet been clarified and mechanism of actions remains unclear. In this research, fifteen novel and three known fluorine-containing rhodacyanine analogues (10c, and 11a-11q) were synthesized and tested the anti-leishmanial activity against promastigote and axenic amastigote stages of L. martiniquensis and L. orientalis, the indigenous Leishmania species of Thailand. The SAR knowledge of this series …
Synthesis Of Coumarins As Carbonic Anhydrase Ii And Α-Glucosidase Inhibitors, Truc Phan Thi Hong
Synthesis Of Coumarins As Carbonic Anhydrase Ii And Α-Glucosidase Inhibitors, Truc Phan Thi Hong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Coumarins have been occupied an important position in medicinal chemistry. In this research, umbelliferone derivatives were evaluated for inhibitory activity of two enzymes, namely carbonic anhydrase II (CA II) and α-glucosidase. First, ether, brominated ether and ester derivatives of umbelliferone were synthesized, characterized and tested for CA II inhibitory activity. However, the inhibition data could not be used to make the exact conclusion about structure-activity relationship owing to their unrepeatable results. For the second part, thirty-four derivatives of umbelliferone (ether, brominated ether, ester, sulfonamide and sulfonate derivatives) were synthesized and explored for anti-α-glucosidase activity. It was disclosed that anti-α-glucosidase activity …
Inhibition Of Hsv-1 Binding By Egcg-Stearate, Valerie Paschalis
Inhibition Of Hsv-1 Binding By Egcg-Stearate, Valerie Paschalis
Theses, Dissertations and Culminating Projects
Herpes simplex virus type 1 (HSV-1) is the causative agent of oral herpes, and is able to establish lifelong latent infection along with painful, recurring symptoms. Epigallocatechin-3- gallate (EGCG) is the most abundant polyphenol derived from green tea (Camellia sinensis), whose anti-inflammatory, antioxidant, anti-cancer, and antiviral properties have been widely studied. Although EGCG is not chemically stable and has poor hydrophobicity, lipophilic derivatives of EGCG have shown increased stability as well as increased antiviral efficacy against HSV. Previous studies have demonstrated that EGCG stearate (EGCG-S), a derivative of EGCG esterified at the 4’ position with stearic acid, is able to …
Avoiding Adverse Effects: New Ideas In Drug Discovery For Targeting Pparγ, Trey M. Patton
Avoiding Adverse Effects: New Ideas In Drug Discovery For Targeting Pparγ, Trey M. Patton
Graduate Student Theses, Dissertations, & Professional Papers
Peroxisome proliferator-activated receptor gamma (PPARγ) has been a drug target to treat type 2 diabetes for the last 20 years when rosiglitazone and pioglitazone were approved by the FDA in 1999. While effective at increasing insulin sensitivity, these drugs cause serious adverse effects due to their full agonist characteristics. For that reason, drug discovery efforts have attempted to reduce or prevent the amount of agonist character of new PPARγ targeting ligands. Unfortunately, there have been no new FDA approved drugs for the receptor. There is a need for new ideas to produce better quality pharmaceuticals that lessen the impact of …
Silicone Wristbands As Passive Samplers For Quantitative Measurement Of Wood Smoke Exposure, Hannah J. Wright
Silicone Wristbands As Passive Samplers For Quantitative Measurement Of Wood Smoke Exposure, Hannah J. Wright
Graduate Student Theses, Dissertations, & Professional Papers
Human exposure to biomass smoke is a health concern worldwide. Although many studies have measured particulate matter in wood smoke as a health concern, exposure to mutagenic and carcinogenic volatile and semivolatile compounds remains understudied. This research introduces a novel method of quantitative measurement of exposure to these compounds using silicone wristbands. The study developed a method to extract analytes of interest from the wristbands and quantify a few volatile organic compounds and polycyclic aromatic hydrocarbons with known ill health effects, and then performed linear regressions between extracted levels and exposure to those analytes using controlled exposure studies. Results indicate …
Xflow: An Algorithm For Extracting Ion Chromatograms, Mathew M. Gutierrez, Rob Smith
Xflow: An Algorithm For Extracting Ion Chromatograms, Mathew M. Gutierrez, Rob Smith
Graduate Student Theses, Dissertations, & Professional Papers
Abstract: Mass spectrometry is a fundamental tool for modern proteomics. The increasing availability of mass spectrometry data paired with the increasing sensitivity and fidelity of the instruments necessitates new and more potent analytical methods. To that end, we have created and present XFlow, a feature detection algorithm for extracting ion chromatograms from MS1 LC-MS data. XFlow is a parameter-free procedurally agnostic feature detection algorithm that utilizes the latent properties of ion chromatograms to resolve them from the surrounding noise present in MS1 data. XFlow is designed to function on either profile or centroided data across different resolutions and instruments. This …
Electron Model Based On Helmholtz’S Electron Vortex Theory & Kolmogorov’S Theory Of Turbulence, Florentin Smarandache, Victor Christianto, Robert Neil Boyd
Electron Model Based On Helmholtz’S Electron Vortex Theory & Kolmogorov’S Theory Of Turbulence, Florentin Smarandache, Victor Christianto, Robert Neil Boyd
Branch Mathematics and Statistics Faculty and Staff Publications
In this paper, we explore a new electron model based on Helmholtz’s electron vortex and Kolmogorov theory of turbulence. We also discuss a new model of origination of charge and matter.
Chemometric Method To Enhance Sensitivity And Selectivity For Surface Enhanced Raman Scattering Technique, Nontawat Sricharoen
Chemometric Method To Enhance Sensitivity And Selectivity For Surface Enhanced Raman Scattering Technique, Nontawat Sricharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
The multivariate curve resolution-alternative least square (MCR-ALS) algorithm was modified with sample insertion constraint. This developed method was proposedly used to deconvolute the overlapping signals in Surface enhance Raman attering (SERS) measurement. The developed method was elucidated with the spectral data simulated by using Gaussian distribution function to generate two independent peaks which correspond to capping agent and analyte, respectively. The spectrum of the two peaks was generated with different overlapping levels (RS = 0 – 1.50) and concentration ratio of analyte and capping agent concentration at 0.01 – 1.00. In MCR-ALS with sample insertion constraint, the number of capping …
Determination Of Perchlorate And Thiocyanate Ions By Ion-Selective Membrane And Bulk Optode Techniques Using Experimental Design Approach, Supacha Wirojsaengthong
Determination Of Perchlorate And Thiocyanate Ions By Ion-Selective Membrane And Bulk Optode Techniques Using Experimental Design Approach, Supacha Wirojsaengthong
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to develop the detection method for perchlorate and thiocyanate in aqueous solutions using potentiometric and colorimetric techniques. The optimum conditions were designed by the central composite design (CCD) with response surface methodology (RSM). The potentiometric response of perchlorate‒selective electrode using di‒tripodal amine calix[4]arene copper(II) complex (L1-Cu) in PVC membrane was studied. The optimized pH, ion exchanger and ionophore concentrations were found at pH 8.0, 3.25 mmol/kg and 13.25 mmol/kg, respectively. The optimized condition performed a Nernstian slope of –58.02 mV/decade with R2=0.9994 in a working concentration range of 1.00×10‒6 – 1.00×10‒2 M, and the detection limit was …
Development Of Green Methods For Synthesis Of 2-Aminobenzoxazoles From Organosulfurs, Theeranon Tankam
Development Of Green Methods For Synthesis Of 2-Aminobenzoxazoles From Organosulfurs, Theeranon Tankam
Chulalongkorn University Theses and Dissertations (Chula ETD)
2-aminobenzoxazoles are an important motif in pharmaceutical and chemical industries, however, their preparations involve the use of toxic reagents and organic solvents. Therefore, greener methods for preparation of 2-aminobenzoxazoles are highly desired. In this work, we demonstrate two novel methodologies for synthesis of 2-aminobenzoxazoles in aqueous media. The first method involves the use of "on water" microwave reaction to perform the amination of 2-mercaptobenzoxazoles into 2-aminobenzoxazoles. Various 2-aminobenzoxazoles are synthesized under additive-free condition accelerating by microwave irradiation at 100 oC for 1 hour in moderate to good yields. This synthesis can be applied to prepare 2-aminobenzoxazole in gram scale quantity. …
Bioactive Compounds From Lichen Usnea Aciculifera Vain And Usnic Acid Conjugates, Truong Tuong Lam
Bioactive Compounds From Lichen Usnea Aciculifera Vain And Usnic Acid Conjugates, Truong Tuong Lam
Chulalongkorn University Theses and Dissertations (Chula ETD)
Phytochemical investigation of lichen Usnea aciculifera Vain led to the isolation of nine new dimeric xanthones, usneaxanthones A-I (36–44), along with 36 known compounds (1–35, 45). The chemical structures of the isolated compounds were elucidated by a combination spectroscopic data (1D, 2D NMR, HRESIMS), ECD experiments, and single-crystal X-ray as well as comparison of their NMR data with those in the literature. The biological activities of isolated compounds were evaluated for antibacterial, anti-dengue and cytotoxic activites. The results revealed that depsides may have potential as lead compounds for the development of new antibacterial and anti-dengue agents. Futhermore, dimeric xanthones exhibited …
Continuous Synthesis Of Biodiesel And Glycerol Ether Using Homogeneous And Heterogeneous Catalysts, Natta Rattanapanya
Continuous Synthesis Of Biodiesel And Glycerol Ether Using Homogeneous And Heterogeneous Catalysts, Natta Rattanapanya
Chulalongkorn University Theses and Dissertations (Chula ETD)
In our study, a mixture of p-toluenesulfonic acid and sulfuric acid (TsOH-H2SO4) as a catalyst showed a good performance in transesterification of palm oil (PO) with methanol and etherification of biodiesel with isobutylene. For biodiesel production, the catalyst noticeably accelerated the reaction faster than TsOH and H2SO4 alone and also gave up to 99.8% of the conversion. Etherification of biodiesel with isobutylene in the etherification process using isobutylene/glycerol molar ratio 6:1 at 70°C, in the period of 5 h reaction time, gave high selectivity to produce DTBG and TTBG (81.4%). Furthermore, the catalyst can be reused for 6 cycles of …
Electrospun Nylon 6,6 Nanofibers Functionalized With Β-Cyclodextrin As Solid Phase Extraction Sorbent For Determination Of Parabens, Tassanee Kuakul
Electrospun Nylon 6,6 Nanofibers Functionalized With Β-Cyclodextrin As Solid Phase Extraction Sorbent For Determination Of Parabens, Tassanee Kuakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study, electrospun nanofibers of nylon 6,6 functionalized with β-cyclodextrin (nylon 6,6/β-CD) were fabricated and applied as a sorbent in solid-phase extraction (SPE) for determination of parabens in water. The electrospinning parameters such as polymer concentration, nylon 6,6/β-CD ratio, and electric field strength were investigated in order to obtain uniform nanofibers. The morphology and physical properties of obtained fibers were characterized by scanning electron microscope (SEM), Fourier transforms infrared spectroscopy (FTIR), and BET surface area analysis. The electrospun nylon 6,6/β-CD nanofibers were achieved with diameter in the range of 120 - 150 nm. The additional of β-CD slightly increased …
Esterification Of Lignin As Carbon Fiber Production Precursor, Jarudech Rakphong
Esterification Of Lignin As Carbon Fiber Production Precursor, Jarudech Rakphong
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the optimized condition (i.e., esterifying agent, reaction time, reaction temperature) to modify lignin for utilization as a precursor in carbon fiber production. The lignin was successfully modified by esterification reaction in dimethylformamide solvent under different reaction temperatures and times using different types of fatty acid chloride including butyryl chloride, octanoyl chloride, and lauroyl chloride as an esterifying agent. The effects of fatty acid chloride chain length and degree of substitution on the chemical structure, functional groups, morphology, crystallinity, thermal properties, and solubility of esterified-lignin were studied. The chemical structure of the obtained product was characterized by FTIR …
Effect Of Poly(Lactic Acid) On Properties Of Poly(Butylene Succinate)/Poly(Butylene Succinate-Co-Adipate)/ Poly(Lactic Acid) Blend Films, Narumon Puekpoonpoal
Effect Of Poly(Lactic Acid) On Properties Of Poly(Butylene Succinate)/Poly(Butylene Succinate-Co-Adipate)/ Poly(Lactic Acid) Blend Films, Narumon Puekpoonpoal
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, biodegradable plastics have drawn a great deal of attention because of plastic pollution. The major drawback of their mechanical properties brought to a limitation of neat biodegradable resins for flexible packaging applications. In this study, binary and ternary blends of poly(butylene succinate-co-adipate) (PBSA) with poly(butylene succinate) (PBS) and poly(lactic acid) (PLA) were melt compounded and successfully prepared into films via blown film line. The aim of this study was to investigate the influence of incorporating PLA including of high molecular weights PLA (Hi-PLA) and low molecular weights (Lo-PLA) into PBSA/PBS blends on processability, phase morphology, mechanical and physical properties. …
Chemical Constituents From The Twigs And Branches Of Garcinia Schomburgkiana, Nindyashinta Darnasmara
Chemical Constituents From The Twigs And Branches Of Garcinia Schomburgkiana, Nindyashinta Darnasmara
Chulalongkorn University Theses and Dissertations (Chula ETD)
The phytochemical investigation from the dichloromethane extract of the twigs and branches of Garcinia schomburgkiana led to the isolation of fourteen known compounds, including 2'-hydroxydihydrochalcone (1), 1-(2'-6'-dihydroxyphenyl)-3-phenyl-1-propanone (2), cudratricusxanthone K (3), pancixanthone A (4), euxanthone (5), 1,4,5-trihydroxyxanthone (6), osajaxanthone (7), 1,2,7-trihydroxyxanthone (8), 1,3,7-trihydroxy-2,4-diprenylxanthone (9), 1,5-dihydroxyxanthone (10), 7-epiclusianone (11), oblongifolin C (12), clusiacitran B (13), and aucuparin (14). Among all isolated compounds, 2'-hydroxydihydrochalcone, 1-(2'-6'-dihydroxyphenyl)-3-phenyl-1-propanone, and cudratricusxanthone K were isolated from genus Garcinia for the first time. Moreover, 7-epiclusianone, pancixanthone A, 1,4,5-trihydroxyxanthone, osajaxanthone, 1,2,7-trihydroxyxanthone, and 1,3,7-trihydroxy-2,4-diprenylxanthone discovered in G. schomburgkiana for the first time. The structures of all isolated compounds were characterized …
Development Of Comprehensive Two Dimensional Gas Chromatography Coupled With Dean Switch For Analysis Of Volatile Organic Compounds, Nilobon Thongdorn-Ae
Development Of Comprehensive Two Dimensional Gas Chromatography Coupled With Dean Switch For Analysis Of Volatile Organic Compounds, Nilobon Thongdorn-Ae
Chulalongkorn University Theses and Dissertations (Chula ETD)
The ability to identify and quantify compounds in complex matrices is paramount for analysis of petroleum samples. Multidimensional gas chromatography (MDGC) is one of the most powerful techniques to obtain such capability. The recent advance involves development of comprehensive multiple heart-cut (CH/C) technique employing long first and second dimensional (1D and 2D) columns which enhances both 1D and 2D analyte peak capacity. In addition, short pulse transfer from the first (1D) to the second dimensional (2D) separation with rapid cycle times can be applied which enhances separation power and fastens the analysis time to obtain comprehensive chemical profile of a …
ผลของสารตัวเติมซิลิกาต่อสมบัติแก้มยาง, ทศพร ขุมเงิน
ผลของสารตัวเติมซิลิกาต่อสมบัติแก้มยาง, ทศพร ขุมเงิน
Chulalongkorn University Theses and Dissertations (Chula ETD)
ในอุตสาหกรรมการผลิตยางรถยนต์ที่มีการแข่งขันทางด้านคุณภาพและราคาของยางล้อนั้น ข้อมูลของโรงงานได้บ่งชี้ว่าคอมพาวนด์แก้มยางเป็นส่วนที่ถูกผลิตมากที่สุด โดยผงเขม่าดำ (Carbon black) ถูกใช้สารตัวเติมนั้นมีราคาที่สูง ดังนั้นงานวิจัยนี้มีแนวคิดที่จะใช้สารตัวเติมซิลิกา (Silica) ที่มีราคาถูกกว่ามาศึกษาผลการทบของสารตัวเติมซิลิกาที่มีต่อคอมพาวนด์แก้มยางโดยศึกษาปริมาณการใช้สารตัวเติมซิลิกาที่เหมาะสมเพื่อทดแทนการเติมผงเขม่าดำในการผลิตคอมพาวนด์แก้มยาง โดยศึกษาอัตราส่วนระหว่างซิลิกาต่อผงเขม่าดำที่ปริมาณการเติมสารตัวเติมคงที่ที่ 51 phr โดยมีสัดส่วนซิลิกาต่อผงเขม่าดำดังนี้ 51:0, 48.5:2.5, 46:5, 43.5:7.5 phr และศึกษาผลของปริมาณการใส่สารคู่ควบไซเลนในสัดส่วนร้อยละของปริมาณซิลิกาที่ 0% 2% และ 10% โดยน้ำหนัก ทำการศึกษาค่าความหนืดมูนนี่ พฤติกรรมการคงรูป ค่าความหนาแน่นของพันธะเชื่อมขวาง ค่าการกระเด้งกระดอน ค่าความแข็ง สมบัติแรงดึง และสมบัติการต้านทานความร้อน ซึ่งผลจากการวิจัยแสดงให้เห็นว่าค่าความหนืดมูนนี่และกระจายตัวของสารตัวเติมไม่เกิดการเปลี่ยนแปลงที่เห็นได้ชัดซึ่งเป็นผลจากการที่ใส่สารตัวเติมซิลิกาในปริมาณที่น้อยแต่จะเห็นได้ว่าเมื่อปริมาณซิลิกาเพิ่มขึ้นจะส่งผลให้พฤติกรรมการคงรูปและระยะยืด ณ จุดขาดของคอมพาวนด์มีค่าเพิ่มสูงขึ้น โดยสัดส่วนการใส่ซิลิกา 7.5 phr และไม่มีการใส่สารคู่ควบไซเลน พบว่าระยะเวลาสกอร์ช และระยะเวลาในการคงรูป มีค่าสูงสุดเท่ากับ 7.24 นาทีและ 16.14 นาที ตามลำดับ อย่างไรก็ตามการเพิ่มปริมาณของซิลิกาส่งผลให้ค่าความหนาแน่นของพันธะเชื่อมขวาง ค่าการกระเด้งกระดอน ค่าความแข็ง และค่าความต้านแรงดึงมีค่าลดลงเมื่อเทียบกับคอมพาวนด์แก้มยางที่ใส่เพียงผงเขม่าดำเนื่องจากการถูกดูดซับของสารเร่งจากหมู่ไซลานอลบนพื้นผิวของซิลิกา
การใช้ผลิตภัณฑ์จุลินทรีย์เพื่อการกำจัดสีย้อมรีแอกทีฟในสารละลายสีย้อมที่ใช้แล้ว, ฐิติกานต์ นิลแก้ว
การใช้ผลิตภัณฑ์จุลินทรีย์เพื่อการกำจัดสีย้อมรีแอกทีฟในสารละลายสีย้อมที่ใช้แล้ว, ฐิติกานต์ นิลแก้ว
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้ได้คัดเลือกผลิตภัณฑ์จุลินทรีย์ทางการค้า 3 ชนิด (ผลิตภัณฑ์จุลินทรีย์ T B และ F) ที่มีแนวโน้มในการกำจัดสีย้อมรีแอกทีฟ ได้แก่ 1)Novacron Super Black-G 2)Novacron Red S-B และ 3)Novacron Orange C-3R จากการทดลองพบว่าผลิตภัณฑ์จุลินทรีย์ B สามารถกำจัดสีในสารละลายสีได้ดีที่สุด และเมื่อศึกษาความสามารถของผลิตภัณฑ์จุลินทรีย์ B ในการกำจัดสีรีแอกทีฟในสารละลายสีที่มีน้ำและสี ทดลองในภาวะต่างๆ ของค่าพีเอช อุณหภูมิและปริมาณจุลินทรีย์ ณ ภาวะสถิตและเขย่า พบว่า ภาวะที่เหมาะสมต่อการกำจัดสีรีแอกทีฟทั้งสามสี คือพีเอช 8 เติมผลิตภัณฑ์จุลินทรีย์ B 0.7 กรัมในสารละลายสีความเข้มข้น 100 มิลลิกรัมต่อลิตร ปริมาตร 100 มิลลิลิตร บ่มที่ภาวะสถิต อุณหภูมิ 40 องศาเซลเซียส เป็นเวลา 6 วัน แล้วนำภาวะที่เหมาะสมเบื้องต้นมาศึกษาความสามารถของผลิตภัณฑ์จุลินทรีย์ B ในการกำจัดสี Novacron Super Black-G ในสารละลายสีที่มีด่างและเกลือพบว่า สามารถกำจัดสารละลายสีที่มีด่างและที่มีด่างและเกลือได้ 87.44 และ 90.61 เปอร์เซ็นต์ตามลำดับ ภายใน 6 วัน ผลการวิเคราะห์คุณภาพน้ำเสียหลังกำจัดสีด้วยผลิตภัณฑ์จุลินทรีย์ B พบว่า ค่าพีเอช ของแข็งละลายน้ำทั้งหมด (Total Dissolved Solids; TDS) และของแข็งแขวนลอยทั้งหมด (Total Suspended Solid; TSS) ไม่เกินมาตรฐานน้ำทิ้งสำหรับอุตสาหกรรมสิ่งทอ ผลการวิเคราะห์โครงสร้างทางเคมีของสีก่อนและหลังกำจัดสีโดยใช้เทคนิค FTIR และ HPLC พบว่า ผลิตภัณฑ์จุลินทรีย์ B สามารถย่อยสลายหมู่โครโมฟอร์หรือหมู่เอโซ (-N=N-) ทำให้พันธะเอโซของสีแตกออกแล้วเกิดเป็นสารแอโรแมติกเอมีน ทำให้ความเข้มสีลดลง ในขณะที่ผลการวิเคราะห์กรดออกซาลิกที่อาจเกิดขึ้นจากการย่อยสลายสี Novacron Super Black-G ของผลิตภัณฑ์จุลินทรีย์ B พบว่าไม่สามารถตรวจสอบด้วยเทคนิค HPLC …
Reactivity Of Copper Complexes For Alkane Oxidation Under Mild Conditions, Jantira Chimlert
Reactivity Of Copper Complexes For Alkane Oxidation Under Mild Conditions, Jantira Chimlert
Chulalongkorn University Theses and Dissertations (Chula ETD)
Alkane oxidation is one of the most important reactions for chemical synthesis and petrochemical manufacture such as nylon and nylon-6,6 productions. Due to the inertness of alkane, the extreme conditions including high temperature and pressure, strong oxidizing agent and precious metal catalyst were required to accomplish the oxidation reaction. In this thesis, complexes of copper(II) which is an earth-abundant metal were investigated for catalysis of alkane oxidation under mild condition. The effect of denticity and delocalized p-electron moiety (i.e. anthracene) on polypyridyl amine supporting ligand toward alkane oxidation was examined. All Cu(II) complexes (CuDPA, CuTMPA, CuADPA and CuATPA) were successfully …
Chemical And Tribological Characteristics Of Petroleum-Based Lubricant For Microelectronics Device Fabrication, Chanikan Polpattanakul
Chemical And Tribological Characteristics Of Petroleum-Based Lubricant For Microelectronics Device Fabrication, Chanikan Polpattanakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Petroleum-based lubricant is used instead of water-based lubricant to reduce the materials corrosion of developed slider in the final lapping process. In this research we focused on the study of the characteristics and performance of petroleum-based lubricants. Three base-lubricants ,which are petroleum hydrocarbon (PHC), synthetic hydrocarbon A (SHA) and synthetic hydrocarbon B (SHB), were found that they are the saturated hydrocarbon with the range of hydrocarbon chain consisted of the carbon atoms C10 - C16, C12 – C20 and C20 – C27 respectively. The three base-lubricants were mixed in the ratio similar to that of commercial lubricant and the ratio …
Biocompatible Materials Loaded With Plant Extract For Ph Sensing, Kasitnun Chayavanich
Biocompatible Materials Loaded With Plant Extract For Ph Sensing, Kasitnun Chayavanich
Chulalongkorn University Theses and Dissertations (Chula ETD)
The pH-sensitive films and resin were developed based on natural pH-sensitive coloring agents and biocompatible polymers. Anthocyanins and a curcumin derivative were selected as the natural pH-sensitive coloring agents. At first, anthocyanins were extracted from red radish and their contents were determined by using the pH-differential method. Difluoro boron curcumin was synthesized to improve its photophysical and stability properties. Next, both coloring agents were characterized by UV-Vis, FT-IR, and NMR techniques as well as their color response in solution was studied in different pHs with UV-Vis profiles. The results showed that the red radish anthocyanin solution could change the colors …
Nanoscale Building Blocks: Bridging The Gap Between Potential And Realized Applications, Nicole Ritter
Nanoscale Building Blocks: Bridging The Gap Between Potential And Realized Applications, Nicole Ritter
Theses and Dissertations (Comprehensive)
The vast potential of nanoparticles and nanotechnology remains largely untapped; the crucial bottleneck being the knowledge gap between making and using nanoparticles (NPs). This PhD work bridges this gap by focusing on synthesizing nanoparticles with applications at the forefront. Four peer-reviewed publications are presented in Chapters 3-6, a safety and toxicological perspective is given in Chapter 7, and current work and future progress are summarized in Appendix 1. Bimorphic silver nanoparticles were prepared, presenting an innovative method to synthesize diverse nanostructures using polymeric surface blocking to break symmetry in seeded regrowth (Chapter 3).1 Silver stars with D5h symmetry …
Temperature-Dependent Kinetic Studies Of Arsenicals Adsorption From Solution To Hematite Nanoparticles, Sara Soldoozy
Temperature-Dependent Kinetic Studies Of Arsenicals Adsorption From Solution To Hematite Nanoparticles, Sara Soldoozy
Theses and Dissertations (Comprehensive)
Surface chemistry is the study of the chemical and physical phenomena that transpire at interfaces such as liquid-solid, solid-gas, liquid-gas, and liquid-liquid. To study the reactions occurred at the surfaces, surface sensitive techniques come to play. Adsorption of arsenical compounds (liquid adsorbate), particularly arsenate (iAs) and dimethylarsinic acid (DMA), to the surface of iron bearing materials (solid adsorbent) that frequently are found in geosorbents such as hematite (Fe2O3) has been studied in this thesis. Arsenical compounds can pollute the environment through natural sources and anthropogenic activities, and ultimately contaminate water. Absorbing these pollutants to a material …
Chemical Synthesis Of Galacto-Oligosaccharides And Evaluation Of Their Prebiotic Properties, Pranpariya Ponpakdee
Chemical Synthesis Of Galacto-Oligosaccharides And Evaluation Of Their Prebiotic Properties, Pranpariya Ponpakdee
Chulalongkorn University Theses and Dissertations (Chula ETD)
Galacto-oligosaccharides (GOS) are composed of galactose and glucose between 2–8 units or disaccharide comprising 2 units of galactose linked by glycosidic bonds. GOS exhibits prebiotic activity and widely used in infant formula. Commercial GOS was achieved as mixture by enzymatic synthesis of lactose with β-galactosidase. Due to the nature of the enzymatic derived-GOS, the structure-activity relationship of GOS and prebiotic activity is mainly ambiguous. In this work, we presented the development towards a production of GOS by chemical synthesis starting from lactose. First, lactose was isolated from liquid whey with 3.90% w/v recovery. Lactose was then hydrolyzed to produce galactose …
Synthesis And Photocatalytic Activity Of Ag-Tio2 For Organic Compound Removal, Tri Rahmawati
Synthesis And Photocatalytic Activity Of Ag-Tio2 For Organic Compound Removal, Tri Rahmawati
Chulalongkorn University Theses and Dissertations (Chula ETD)
Organic pollutants such as dyes and volatile organic compounds which are widely used materials in industries and discharged daily to the aqueous environment can be harmful to human health. This present study proposed an environmentally friendly approach for silver-doped titanium dioxide (Ag-TiO2) synthesis as a photocatalyst material used as photocatalytic organic pollutant degradation. The synthesis of Ag-TiO2 was conducted by using dry and wet ball milling sol−gel method with the aqueous extract of turmeric powder under 6000C calcination. The effect of different Ag contents of 0.5%, 1%, 3%, and 6% in Ag-TiO2 on the degradation of the organic pollutants was …