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2019

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Articles 1501 - 1530 of 1773

Full-Text Articles in Chemistry

Elq-331 As A Prototype For Extremely Durable Chemoprotection Against Malaria, Martin J. Smilkstein, Sovitj Pou, Alina Krollenbrock, Lisa A. Bleyle, Rozalia A. Dodean, Lisa Frueh, David J. Hinrichs, Multiple Additional Authors Jan 2019

Elq-331 As A Prototype For Extremely Durable Chemoprotection Against Malaria, Martin J. Smilkstein, Sovitj Pou, Alina Krollenbrock, Lisa A. Bleyle, Rozalia A. Dodean, Lisa Frueh, David J. Hinrichs, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

The potential benefits of long-acting injectable chemoprotection (LAI-C) against malaria have been recently recognized, prompting a call for suitable candidate drugs to help meet this need. On the basis of its known pharmacodynamic and pharmacokinetic profiles after oral dosing, ELQ-331, a prodrug of the parasite mitochondrial electron transport inhibitor ELQ-300, was selected for study of pharmacokinetics and efficacy as LAI-C in mice.

Four trials were conducted in which mice were injected with a single intramuscular dose of ELQ-331 or other ELQ-300 prodrugs in sesame oil with 1.2% benzyl alcohol; the ELQ-300 content of the doses ranged from 2.5 to 30 …


Esterification Of Lignin As Carbon Fiber Production Precursor​, Jarudech Rakphong Jan 2019

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 Jan 2019

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 Jan 2019

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 …


Florida Science: The Science That Makes Florida Different, Terence W. Cavanaugh Jan 2019

Florida Science: The Science That Makes Florida Different, Terence W. Cavanaugh

Secondary Level Resources

This book was created to assist students with their understanding of how science occurs in Florida. When teaching science or any subject it’s important to remember to begin with the concrete and then move to the abstract. I have found that it has helped my students when I begin by teaching science concepts in a concrete manner and expand from there. For example, when I taught about topographic maps, the students were much more successful in their learning when I started with local topographic maps that included the school and the surrounding area than with places that had mountains or …


การเปลี่ยนปาล์มโอเลอินเป็นเชื้อเพลิงชีวภาพสำหรับอากาศยานบนนิกเกิลที่รองรับด้วยซีโอไลต์ชนิดบีตาและเอชวาย, ธนวัฒน์ สุขอนันต์ Jan 2019

การเปลี่ยนปาล์มโอเลอินเป็นเชื้อเพลิงชีวภาพสำหรับอากาศยานบนนิกเกิลที่รองรับด้วยซีโอไลต์ชนิดบีตาและเอชวาย, ธนวัฒน์ สุขอนันต์

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้สนใจศึกษาการผลิตเชื้อเพลิงชีวภาพสำหรับอากาศยานที่มีเสถียรภาพในการทำปฏิกิริยากับออกซิเจน เพิ่มปริมาณโซ่กิ่ง โซ่ตรง และลดปริมาณอะโรมาติก จากปาล์มโอเลอินบนนิกเกิลที่รองรับด้วยซีโอไลต์ชนิดบีตาและเอชวาย ตัวแปรที่ศึกษาประกอบด้วย อุณหภูมิ 430 - 460 องศาเซลเซียส ปริมาณนิกเกิล ร้อยละ 0 – 15 โดยน้ำหนัก ความดันบรรยากาศไฮโดรเจนเริ่มต้น 0 – 10 บาร์ และน้ำหนักตัวเร่งปฏิกิริยา ร้อยละ 0 – 5 โดยน้ำหนัก ที่เวลาในการทดลอง 5 ชั่วโมง ภาวะที่เหมาะสมต่อการเกิดปฏิกิริยาแครกกิง ดีออกซิจีเนชั่น และไอโซเมอไรเซชั่นต่อการเกิดน้ำมันเชื้อเพลิงชีวภาพสำหรับอากาศยาน คือ อุณหภูมิ 430 องศาเซลเซียส ที่ความดันไฮโดรเจนเริ่มต้น 10 บาร์ โดยใช้นิกเกิล ร้อยละ 5 โดยน้ำหนักบนซีโอไลต์ชนิดเอชวาย ปริมาณร้อยละ 5 โดยน้ำหนักเป็นตัวเร่งปฏิกิริยา เป็นเวลา 5 ชั่วโมง โดยให้ร้อยละผลได้ของผลิตภัณฑ์น้ำมัน 63 ร้อยละผลได้ของแก๊ส 30 และร้อยละผลได้ของของแข็ง 7 โดยน้ำหนัก ซึ่งองค์ประกอบของผลิตภัณฑ์น้ำมันที่ได้มีร้อยละผลได้ของน้ำมันเชื้อเพลิงสำหรับอากาศยานร้อยละ 56 แก๊สโซลีนร้อยละ 28 ดีเซลร้อยละ13 และกากน้ำมันร้อยละ3 โดยการเลือกสรรของผลิตภัณฑ์น้ำมันเป็นดังนี้ ไฮโดรคาร์บอนโซ่ตรงร้อยละ 58 อะโรมาติกร้อยละ 23 และโซ่กิ่งร้อยละ 19 ตามลำดับ


Sub-Cloning, Expression, And Purification Of The Wild Type And Mutated Sigma-1 Receptor, Christopher Koch Jan 2019

Sub-Cloning, Expression, And Purification Of The Wild Type And Mutated Sigma-1 Receptor, Christopher Koch

Undergraduate Honors Thesis Collection

The Sigma-1 receptor (S1R) is an important pharmaceutical target that has been linked to several neurological diseases and drug addiction. It has been proposed that multimerization of S1R is important for attenuating its interactions with the dopamine transporter (DAT) and that S1R agonists promote dissociation to a monomeric form necessary for DAT interaction. This project aims to assess the role of the N-terminal transmembrane domain in oligomerization and binding activity of the mammalian Sigma-1 receptor (S1R). N-terminal truncations lacking the transmembrane domain and the E102Q variant, which displays altered activity and cellular localization, were expressed, purified in order to determine …


Removal Of Antimony And Bismuth From Copper Electrorefining Electrolyte By Two Proprietary Solvent Extraction Extractants, Andrew Artzer Jan 2019

Removal Of Antimony And Bismuth From Copper Electrorefining Electrolyte By Two Proprietary Solvent Extraction Extractants, Andrew Artzer

Masters Theses

"Antimony and bismuth are two of the most problematic impurities in copper electrorefining (ER). Because of this, much research has been done investigating the ways to remove them. Processes that are currently being used industrially include anode additions, liberators, ion exchange (IX), and solvent extraction (SX). Of these, liberators and anode additions are the most common while SX is the least, mostly being used for arsenic removal. There are other methods that have been evaluated, but are not in commercial use. These include the use of various electrolyte additives, and adsorbents such as bentonite clay and heavy metal sulfates.

Two …


Environmental Forensic Characterization Of Former Rail Yard Soils Located Adjacent To The Statue Of Liberty In The New York/New Jersey Harbor, Diane Hagmann, Michael A. Kruge, Matthew Chi-Hymn Cheung, Maria Mastalerz, José Luis Gallego, Jay Prakash Singh, Jennifer Krumins, Xiaona N. Li, Nina M. Goodey Jan 2019

Environmental Forensic Characterization Of Former Rail Yard Soils Located Adjacent To The Statue Of Liberty In The New York/New Jersey Harbor, Diane Hagmann, Michael A. Kruge, Matthew Chi-Hymn Cheung, Maria Mastalerz, José Luis Gallego, Jay Prakash Singh, Jennifer Krumins, Xiaona N. Li, Nina M. Goodey

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Identifying inorganic and organic soil contaminants in urban brownfields can give insights into the adverse effects of industrial activities on soil function, ecological health, and environmental quality. Liberty State Park in Jersey City (N.J., USA) once supported a major rail yard that had dock facilities for both cargo and passenger service; a portion remains closed to the public, and a forest developed and spread in this area. The objectives of this study were to: 1) characterize the organic and inorganic compounds in Liberty State Park soils and compare the findings to an uncontaminated reference site (Hutcheson Memorial Forest); and 2) …


Synthesis And Catalytic Activity Of Ionic Palladium \Textit{N}-Heterocyclic Carbene Complexes, Sedat Yaşar, Mi̇tat Akkoç, Namik Özdemi̇r, İsmai̇l Özdemi̇r Jan 2019

Synthesis And Catalytic Activity Of Ionic Palladium \Textit{N}-Heterocyclic Carbene Complexes, Sedat Yaşar, Mi̇tat Akkoç, Namik Özdemi̇r, İsmai̇l Özdemi̇r

Turkish Journal of Chemistry

The synthesis of 3 benzimidazole-based ionic Pd(II)-NHC complexes (NHC:$N$-heterocyclic carbene) is presented. The structures of the complexes are as follows: [NHC-PdBr$_{3}$]$^{-}$[NHC]$^{+}$. The ionic palladium(II)-NHC complexes were synthesized in high yields and were fully characterized by nuclear magnetic resonance spectroscopy, X-ray diffraction, LC-MS/MS, and elemental analysis. These complexes have been identified as active catalysts in Suzuki-Miyaura reactions in a solution of 2-propanol and water at room temperature for different aryl bromides.


An Ultrasensitive Electrochemical Immunosensor Platform Based On Disposable Ito Electrode Modified By 3-Cptms For Early Detection Of Parathyroid Hormone, İnci̇ Uludağ, Mustafa Kemal Sezgi̇ntürk Jan 2019

An Ultrasensitive Electrochemical Immunosensor Platform Based On Disposable Ito Electrode Modified By 3-Cptms For Early Detection Of Parathyroid Hormone, İnci̇ Uludağ, Mustafa Kemal Sezgi̇ntürk

Turkish Journal of Chemistry

Parathyroid hormone (PTH) is a polypeptide containing 84 amino acids secreted by cells of the parathyroid glands. Imbalances of parathyroid levels cause medical problems such as osteoporosis, mental disorders, pancreatitis, kidney stones, cancer, and other symptoms. In this study, we aimed to design an ultrasensitive electrochemical immunosensor for PTH detection. Indium tin oxide (ITO) was used as an electrode for electrochemical impedance spectroscopy (EIS) measurements. ITO sheets were modified by using 3-cyanopropyltrimethoxysilane (3-CPTMS) self-assembled monolayers (SAMs) for immobilizing the anti-PTH antibody via covalent interactions. Cyclic voltammetry (CV) and EIS methods were applied to characterize immobilization steps. Therefore, 1% was selected …


Effect Of Polyvinyl Alcohol/Chitosan Blend Ratios On Morphological, Optical, And Thermal Properties Of Electrospun Nanofibers, Gökhan Açik, Musa Kamaci, Burak Özata, Cahi̇de Eli̇f Özen Cansoy Jan 2019

Effect Of Polyvinyl Alcohol/Chitosan Blend Ratios On Morphological, Optical, And Thermal Properties Of Electrospun Nanofibers, Gökhan Açik, Musa Kamaci, Burak Özata, Cahi̇de Eli̇f Özen Cansoy

Turkish Journal of Chemistry

In this study, the electrospinning method was used to prepare polyvinyl alcohol (PVA)/chitosan (CS) blend nanofibers from their solutions. The effect of blend ratios (PVA/CS: 1%, 3%, 5%, and 7% (w/w)), applied voltage, and flow rate on the morphological, optical, and thermal properties of electrospun nanofibers were investigated by scanning electron microscopy (SEM), fluorescence and UV-Vis spectroscopies, and thermogravimetric analysis (TGA), respectively. Fourier transform infrared spectroscopy analysis indicated the existence of related functional groups of both PVA and CS in the electrospun fibers. During the electrospinning process, the maximum possible ratio of CS was 7% (w/w). SEM images indicated that …


Fuel Characteristics And Combustion Behavior Of Seaweed-Derived Hydrochars, İsmai̇l Cem Kantarli, Mehmet Pala, Yeli̇z Yildirim, Jale Yanik, Maria Helena Abreu Jan 2019

Fuel Characteristics And Combustion Behavior Of Seaweed-Derived Hydrochars, İsmai̇l Cem Kantarli, Mehmet Pala, Yeli̇z Yildirim, Jale Yanik, Maria Helena Abreu

Turkish Journal of Chemistry

In this study, conversion of seaweeds into hydrochars was investigated with the aim of obtaining a renewable energy feedstock. The seaweeds Fucus serratus and Alaria esculenta, and a mixture of seaweeds, mainly consisting of Cystoseria sp$.$ and Laurencia sp$.$, were subjected to hydrothermal carbonization (HTC) in subcritical water at three different temperatures: 200, 225, and 250 $^{\circ}$C. Fuel characteristics and chemical properties of the derived hydrochars were determined using the standard fuel analysis and spectroscopic methods. The combustion behavior of seaweeds and hydrochars was examined via nonisothermal thermogravimetric analysis under air atmosphere. The seaweed-derived hydrochar yields were lower than those …


Preparation Of Epoxidized Sunflower Oil Metal Soap Derivatives And Their Use As Heat Stabilizers For Polyvinyl Chloride, Ouassila Chelil, Naima Belhaneche-Bensemra, Daniel Lopez Garcia, Marta Fernandez-Garcia, Mohamed Tahar Benaniba Jan 2019

Preparation Of Epoxidized Sunflower Oil Metal Soap Derivatives And Their Use As Heat Stabilizers For Polyvinyl Chloride, Ouassila Chelil, Naima Belhaneche-Bensemra, Daniel Lopez Garcia, Marta Fernandez-Garcia, Mohamed Tahar Benaniba

Turkish Journal of Chemistry

The aim of this work was to prepare metal soaps of epoxidized sunflower oil (ESO) and use them as thermal stabilizers for polyvinyl chloride (PVC). For that purpose, commercial sunflower oil was first epoxidized and then used to prepare (Ba, Zn, Pb, and Cd) metal soap derivatives, which were characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The prepared metal soaps derivatives of ESO were used as thermal stabilizers for plasticized PVC. Discoloration, residual thermal stability at 200 $^{\circ}$C , and rheological properties of PVC samples were tested. The structural modifications were investigated …


Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp Jan 2019

Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp

Dissertations, Master's Theses and Master's Reports

Boreal peatlands store approximately one third of the earth’s terrestrial carbon, locked away in currently waterlogged and frozen conditions. Peatlands of boreal and arctic ecosystems are affected increasingly by shifting hydrology caused by climate change. The consequences of these relatively rapid ecosystem changes on carbon cycling between the landscape and the atmosphere could provide an amplifying feedback to climate warming. Alternatively, the advancement of terrestrial vegetation into once waterlogged soils could uptake carbon as a sink. Previous work suggests that fens will become an increasingly dominant landscape feature in the boreal. However, studies investigating fens, their response to hydrologic and …


Hydrogen Storage In Formic Acid As A Renewable Energy Source Using Heterogeneous Catalysis, Obaid Aldosari Jan 2019

Hydrogen Storage In Formic Acid As A Renewable Energy Source Using Heterogeneous Catalysis, Obaid Aldosari

Turkish Journal of Chemistry

One of the most vital chemicals, which is not only found naturally but can also be synthesized in the laboratory, is formic acid (FA). FA is a key byproduct of several second-generation biorefinery processes as well, and it is used in several pharmaceutical and industrial applications. Recently, another significant use of FA that is taking the lead is as a form of fuel. This could either involve reformation, as a possible form of chemical hydrogen storage, or be done without reformation in the form of FA fuel cells, in particular because FA fuel cells are much more effective than other …


$N$-Acylazole Mediated Stereoselective And Regioselective Synthesis Of $N$-Substituted Azole Acrylonitriles, Osman Aydin, Şule Kökten, Hakan Ünver, İlhami̇ Çeli̇k Jan 2019

$N$-Acylazole Mediated Stereoselective And Regioselective Synthesis Of $N$-Substituted Azole Acrylonitriles, Osman Aydin, Şule Kökten, Hakan Ünver, İlhami̇ Çeli̇k

Turkish Journal of Chemistry

Regio- and stereoselective synthesis of $N$-substituted azole acrylonitriles has been achieved smoothly in $N,N$-dimethylformamide (DMF) in the presence of potassium carbonate (K$_{2}$CO$_{3})$ as a base catalyst. $N$-Substituted azole acrylonitriles were obtained in moderate to good yields (39%-87%) with a one-pot reaction between readily available $N$-acetylazoles and Baylis-Hillman nitriles. The structural determinations were accomplished by NOESY $^{1}$H NMR and X-ray crystallography.


Roaming Transition States And Highly Accurate Thermochemistry: A Pepico Study Of Two Small Combustion Systems, Kyle John Covert Jan 2019

Roaming Transition States And Highly Accurate Thermochemistry: A Pepico Study Of Two Small Combustion Systems, Kyle John Covert

University of the Pacific Theses and Dissertations

Two small combustion systems, methyl hydroperoxide (CH3OOH) and 2-propanol ((CH3)2CHOH), were studied using imaging photoelectron photoion coincidence spectroscopy (iPEPICO), which combines photoelectron spectroscopy and photoionization mass spectrometry to detect coincident photoelectron-photoion pairs. In the photon energy range of 11.4–14.0 eV, energy selected CH3OOH+ ions dissociate into CH2OOH+, HCO+, CH3+, and H3O+ ions. The lowest-energy dissociation channel is the formation of the cation of the smallest “QOOH” radical, CH2OOH+. A statistical rate model fitted to the …


อุปกรณ์ไฮบริดเซลล์สุริยะ/เทอร์โมอิเล็กทริกสำหรับการใช้พลังงานแสงอาทิตย์อย่างมีประสิทธิภาพ, สุทธิดา จงอุดมฤกษ์ Jan 2019

อุปกรณ์ไฮบริดเซลล์สุริยะ/เทอร์โมอิเล็กทริกสำหรับการใช้พลังงานแสงอาทิตย์อย่างมีประสิทธิภาพ, สุทธิดา จงอุดมฤกษ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ในงานวิจัยที่ผ่านมามีแนวความคิดสร้างอุปกรณ์ร่วมระหว่างเซลล์สุริยะและเทอร์โมอิเล็กทริกเพื่อใช้แปลงพลังงานจากแสงและความร้อนที่ได้จากดวงอาทิตย์มาผลิตไฟฟ้าได้ในเวลาเดียวกัน อย่างไรก็ตาม อุปกรณ์ร่วมดังกล่าวผลิตจากวัสดุมีที่มีโลหะหนักและเป็นพิษต่อสิ่งแวดล้อม ดังนั้น ในงานวิจัยนี้จึงได้ศึกษาสมบัติทางเทอร์โมอิเล็กทริกของพอลิเมอร์ที่มีหมู่ฟังก์ชั่นชนิดพอลิ(3,4เอททีลีนไดออกซีไทโอฟีน):พอลิ(สไตรีนซัลโฟเนต) (PEDOT:PSS) เพื่อนำมาใช้เป็นวัสดุเทอร์โมอิเล็กทริกทดแทนวัสดุที่เป็นพิษดังกล่าวข้างต้น จากผลการทดสอบเบื้องต้น พบว่า สภาพนำไฟฟ้าของ PEDOT:PSS เมื่อเติมสารเจือชนิดเอททีลีนไกลคอล (EG) เพิ่มขึ้นเมื่อปริมาณร้อยละของ EG เพิ่มสูงขึ้น ในขณะที่สัมประสิทธิ์ซีเบกมีค่าคงที่และมีค่าเพิ่มขึ้นเป็น 20.0±0.1 μV/K เมื่อเติมสารเจือชนิดไฮดราซีนไฮเดรต ร้อยละ 1.58 โดยน้ำหนัก อย่างไรก็ตาม สภาพนำไฟฟ้าของ PEDOT:PSS เจือด้วย EG ร้อยละ 48 โดยน้ำหนักมีค่าลดลงอย่างมีนัยสำคัญเมื่อเติมสารเจือชนิดไฮดราซีนไฮเดรต เมื่อพิจารณาผลของแฟกเตอร์กำลังไฟฟ้ามีค่าสูงสุดที่ 4.38±0.40 µW/m∙K2 เมื่อเติมสารเจือ EG ร้อยละ 48 โดยน้ำหนักและปราศจากการเจือด้วยสารเจือชนิดไฮดราซีนไฮเดรต ผลการนำสารละลาย PEDOT:PSS ที่ผ่านการปรับปรุงสมบัติทางเทอร์โมอิเล็กทริกมาขึ้นรูปเป็นวัสดุเทอร์โมอิเล็กทริกเพื่อใช้ในอุปกรณ์ร่วมเซลล์สุริยะ/เทอร์โมอิเล็กทริก พบว่า อุปกรณ์ร่วมเซลล์สุริยะ/เทอร์โมอิเล็กทริกสามารถผลิตกำลังไฟฟ้าได้มากกว่าเซลล์สุริยะเดี่ยวได้ถึง ร้อยละ 15 ที่ผลต่างอุณหภูมิ 35 องศาเซลเซียสระหว่างฝั่งด้านร้อนและด้านเย็นของเทอร์โมอิเล็กทริก ผลงานวิจัยที่ได้สามารถใช้เป็นพื้นฐานเพื่อต่อยอดแนวคิดสำหรับการพัฒนาอุปกรณ์ร่วมเซลล์สุริยะ/เทอร์โมอิเล็กทริก สำหรับการผลิตไฟฟ้าจากพลังงานแสงอาทิตย์อย่างมีประสิทธิผลโดยใช้วัสดุเทอร์โมอิเล็กทริกฐานพอลิเมอร์ที่เป็นมิตรต่อสิ่งแวดล้อม


Development Of Cooperative Photocatalysts, Tossapong Phuangburee Jan 2019

Development Of Cooperative Photocatalysts, Tossapong Phuangburee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Photosynthesis involves electron/energy transfer between photocatalyst and catalyst. This concept called “cooperative photocatalyst” is of interest for researchers to develop sustainable photocatalytic systems. In this dissertation, two catalytic systems including graphene oxide (GO) and copper complexes as catalysts were combined with photocatalysts to achieve alcohol oxidation and atom-transfer radical addition (ATRA), respectively. In the first system, GO was modified with porphyrin derivatives (TPP or ZnTPP) using sonication method. The prepared composites were characterized by spectroscopic techniques such as UV-Vis, FTIR, Raman spectroscopy. The photocatalytic activity of the GO-ZnTPP was significantly lower than that of GO-TPP due to the interactions between …


Unexpected Outcomes During The Attempted Iodination Of Biphenol, Henry Nguyen Jan 2019

Unexpected Outcomes During The Attempted Iodination Of Biphenol, Henry Nguyen

Honors Theses

The goal of this research was to create a new procedure to iodinate 4,4- biphenol using a ball miller. Iodination of 4,4-biphenol was first attempted in solution using electrophilic aromatic substitution. Several attempts were made to iodinate 4,4-biphenol, but the general insolubility of crude products inhibited progress. Interestingly, NMR analysis of the aqueous ammonia product suggested that 4,4-biphenol dimerized or polymerized with itself to make an ether. The exact mechanism by which the ether dimer was created is unknown, but the reaction may have occurred using a radical mechanism. Though the original goal of the project is left unmet, a …


Investigation Of Coastal Sea-Fog Formation Using The Wibs (Wide Band Integrated Bioaerosol Sensor) Technique, Shane M. Daly, David O'Connor, David A. Healy, Stig Hellebust, Jovanna Arndt, Eoinj. Mcgillicuddy, Patrick Feeney, Michael Quirke, John C. Wenger, John R. Sodeau Jan 2019

Investigation Of Coastal Sea-Fog Formation Using The Wibs (Wide Band Integrated Bioaerosol Sensor) Technique, Shane M. Daly, David O'Connor, David A. Healy, Stig Hellebust, Jovanna Arndt, Eoinj. Mcgillicuddy, Patrick Feeney, Michael Quirke, John C. Wenger, John R. Sodeau

Articles

Abstract. A wideband integrated bioaerosol sensor (WIBS4) was deployed in Haulbowline Island, Cork Harbour, to detect fluorescence particles in real time during July and September 2011. A scanning mobility particle sizer (SMPS) was also installed providing sizing analysis of the particles over the 10–450nm range. During the campaign, multiple fog formation events occurred; they coincided with dramatic increases in the recorded fluorescent particle counts. The WIBS sizing and fluorescence intensity profiles indicated that the origin of the signals was potentially non-biological in nature (i.e. PBAPs, primary biological aerosol particles). Furthermore, the data did not support the presence of known fluorescing …


Physical And Chemical Trace Evidence From 3d-Printed Firearms, And Use Of A Quadcopter For Targeted Sampling Of Gaseous Mercury In The Atmosphere, Oscar Beauchamp Black Jan 2019

Physical And Chemical Trace Evidence From 3d-Printed Firearms, And Use Of A Quadcopter For Targeted Sampling Of Gaseous Mercury In The Atmosphere, Oscar Beauchamp Black

Electronic Theses and Dissertations

My forensic research resulted in the first peer-reviepaper to address the forensic challenges presented by 3D-printed polymer firearms. The work involved a systematic approach to the analysis of evidence stemming from 3D-printed firearms filling a critical void in current forensic knowledge. We used DART-MS to characterize the polymer evidence left behind by 3D-printed firearms as well as an evaluation of pre-existing firearm and toolmark techniques and fingerprint analysis. We demonstrated that 3D-printed firearms leave behind characteristic polymer residue on cartridge cases bullets and the receiving surface which can be identified using DART-MS. The culmination of the work includes a database …


Electrochemical Studies Involving Co2 Reduction With Rhenium-Based Catalysts And For Guanosine Monophosphate Oxidation, Kayla A. Milano Jan 2019

Electrochemical Studies Involving Co2 Reduction With Rhenium-Based Catalysts And For Guanosine Monophosphate Oxidation, Kayla A. Milano

Electronic Theses and Dissertations

The following chapter of this thesis will cover the oxidation of guanine monophosphate (GMP). GMP has been linked to numerous conditions when it is oxidized or damaged. There have been two oxidation pathways suggested in association to the oxidation of GMP: EPT and MS-EPT. The ideal conditions for GMP’s oxidation is still be studied and collected. The study focuses on the acetate versus phosphate buffer, varying base concentration in phosphate buffer, and the varying concentration of ruthenium complex, a redox mediator.


The Synthesis Of New Donor-Sigma-Acceptor Compounds As Potential Current Rectifiers, Trey Gautier Vaughan Jan 2019

The Synthesis Of New Donor-Sigma-Acceptor Compounds As Potential Current Rectifiers, Trey Gautier Vaughan

Electronic Theses and Dissertations

The zwitterionic D-σ-A’s are characterized by having an anionic donor, a cationic acceptor, an intervening sigma-bond bridge, and an aliphatic tail. The aliphatic tail is of such length as to impart greater solubility in organic solvents since the formal charges on the donor and acceptor lead to poor solubility. Additionally, the aliphatic tail is required for Pockels-Langmuir deposition to facilitate the favorable van der Waal’s packing when combined to form dense monolayer registries. These monolayers may then be suitable for measuring the bulk electrical properties.


A Study To Regioselectively Access Fluorinated Triazoles And Isoxazoles, Sweta Adhikari Jan 2019

A Study To Regioselectively Access Fluorinated Triazoles And Isoxazoles, Sweta Adhikari

Electronic Theses and Dissertations

The objective of the thesis is to develop regioselective methods for mono-fluorination of disubstituted triazoles, both 1,4- and 1,5-regioisomer, and isoxazoles. These strategies focus on one-pot direct access to final mono-fluorinated triazoles and isoxazoles. Eventually, these fluorinated substrates will be screened against various biological targets. Similarly, the optimization study of a regioselective method to generate 5-fluoro-1,4-disubstituted triazole was conducted. This reaction also utilized 1,3-dipolar cycloaddition to synthesize fluorinated triazole. However, difluoroalkene was used as a synthetic equivalent of fluoroalkyne for this method. This resulted into the inversion of polarity affording a different regioisomer. Here, fluoronitroalkene was identified as a synthetic …


High Voltage Dye-Sensitized Solar Cells And Molecular Photocatalysis For Co2 Reduction, Roberta Ramalho Rodrigues Jan 2019

High Voltage Dye-Sensitized Solar Cells And Molecular Photocatalysis For Co2 Reduction, Roberta Ramalho Rodrigues

Electronic Theses and Dissertations

The development of high voltage solar cells is an attractive way to use sunlight to power electrocatalysts for water oxidation, electrocatalysts for CO2 reduction, and consumer electronics. Through careful molecular dye engineering and redox shuttle pairing, our group has reported a single-junction dye-sensitized solar cell (DSC) employing, for the first time, an iron redox mediator (Fe(bpy)33+/2+) in conjunction with a novel wide band gap dye (RR9). This system generates a high photovoltage of 1.42 V. To the best of our knowledge, this system is the highest photovoltage achieved by a single-junction DSC device without metal oxide doping. The RR9/Fe(bpy)33+/2+ redox …


Intramoleculer Hydrogen Bonding In Epoxide, Thiirane, Aziridine And Phosphirane Containing Cyclopentanols, Ben Edward Smith Jan 2019

Intramoleculer Hydrogen Bonding In Epoxide, Thiirane, Aziridine And Phosphirane Containing Cyclopentanols, Ben Edward Smith

Electronic Theses and Dissertations

A recent computational analysis of the stabilizing intramolecular OH· · · O contact in 1,2-dialkyl-2,3-epoxycyclopentanol diastereomers has been extended to thiiriane, aziridine and phosphirane analogues. Density functional theory (DFT), second-order Møller-Plesset perturbation theory (MP2) and CCSD(T) coupled-cluster computations with simple methyl and ethyl substituents indicate that electronic energies of the cis isomers are lowered by roughly 3 to 4 kcal mol−1 when the OH group of these cyclopentanol systems forms an intramolecular contact with the O, S, N or P atom on the adjacent carbon. The results also suggest that S and P can participate in these stabilizing intramolecular interactions …


Bulky Thiolated Gold Nanomolecules: Synthesis, Characterization, Optical Properties, And Atomic Structure, Tanya Clorise Jones Jan 2019

Bulky Thiolated Gold Nanomolecules: Synthesis, Characterization, Optical Properties, And Atomic Structure, Tanya Clorise Jones

Electronic Theses and Dissertations

Gold nanomolecules (NMs) have a distinct number of gold atoms and thiolate ligands, Aux(SR)y, with unique spectroscopic, electrochemical, and chiral properties which are dependent on “x” and “y”. The properties of NMs are dictated by the type of capping ligand. The overall structure, size, surface percentage of ligands, and structure of an entire gold NM is changed based on the type of ligand used to synthesize it. Ligand type, such as aliphatic, aromatic or bulky play a crucial role in determining the size and composition of such NMs. A NM’s composition and properties vary widely depending on the type of …


Functionality Of Membrane Proteins Overexpressed And Purified From E. Coli Is Highly Dependent Upon The Strain, Khadija Mathieu, Waqas Javed, Sylvain Vallet, Christian Lesterlin, Marie-Pierre Candusso, Feng Ding, Xiaohong Nancy Xu, Christine Ebel, Jean-Michel Jault, Cédric Orelle Jan 2019

Functionality Of Membrane Proteins Overexpressed And Purified From E. Coli Is Highly Dependent Upon The Strain, Khadija Mathieu, Waqas Javed, Sylvain Vallet, Christian Lesterlin, Marie-Pierre Candusso, Feng Ding, Xiaohong Nancy Xu, Christine Ebel, Jean-Michel Jault, Cédric Orelle

Chemistry & Biochemistry Faculty Publications

Overexpression of correctly folded membrane proteins is a fundamental prerequisite for functional and structural studies. One of the most commonly used expression systems for the production of membrane proteins is Escherichia coli. While misfolded proteins typically aggregate and form inclusions bodies, membrane proteins that are addressed to the membrane and extractable by detergents are generally assumed to be properly folded. Accordingly, GFP fusion strategy is often used as a fluorescent proxy to monitor their expression and folding quality. Here we investigated the functionality of two different multidrug ABC transporters, the homodimer BmrA from Bacillus subtilis and the heterodimer PatA/PatB …