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Full-Text Articles in Chemistry
Development Of Dna Detection System Using G-Quadruplex As Catalyst For Colorimetric Detection With Pyrrolidinyl Peptide Nucleic Acid, Somlawan Thipkunthong
Development Of Dna Detection System Using G-Quadruplex As Catalyst For Colorimetric Detection With Pyrrolidinyl Peptide Nucleic Acid, Somlawan Thipkunthong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nucleic acid sequence detection is very important for many applications such as the diagnosis of genetic diseases. The development of new, simple yet effective methods is still in great demand. Among several options, colorimetric detection is a technique that does not require complicated instruments and allows the detection by naked eyes. In this work, a new colorimetric DNA detection system was developed using the combination of a pyrrolidinyl peptide nucleic acid (acpcPNA) probe and a G-quadruplex/hemin DNAzyme. The G-quadruplex is formed from G-rich DNA sequences, and in the presence of hemin, a DNAzyme is formed which effectively catalyzes the oxidation …
Fluorescent Chemosensors From Hydrazide Derivatives Of Julolidine, Warakorn Akarasareenon
Fluorescent Chemosensors From Hydrazide Derivatives Of Julolidine, Warakorn Akarasareenon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Three derivatives of N-acylhydrazone julolidine are synthesized and comparatively investigated for their selectivities as metal ion fluorescent sensors. The compound derived from picolinohydrazide is found to be a "turn-on" fluorescent sensor for Cu2+ in aqueous DMSO media. The mechanistic investigation suggests that Cu2+ promotes the hydrolysis reaction of picolinohydrazide moiety to generate a highly fluorescent compound julolidine-9-carboxaldehyde which has a maximum emission signal at 420 nm. This probe shows an extraordinary selectivity for Cu2+ over other metal ions with a detection limit of 0.1 ppm. Under optimal conditions, the determinations of Cu2+ in real water samples are successfully executed. In …
Prediction Of Soil Sorption Coefficient Of Chemicals By Molecular Modeling Technique, Wasin Pithaktrakool
Prediction Of Soil Sorption Coefficient Of Chemicals By Molecular Modeling Technique, Wasin Pithaktrakool
Chulalongkorn University Theses and Dissertations (Chula ETD)
Soil pollution is one of the pollutions caused by nature and human activities, which are mostly the use of insecticide and chemical fertilizer to make plants grow well and produce more products. However, these chemicals are absorbed by soil. In this research work, properties of chemical compound affecting soil sorption were analyzed, and model that can predict soil sorption coefficient of chemicals (KOC) was examined by using quantitative structure property relationship (QSPR) technique. Totally 1,327 compounds were selected, and their three-dimensional structures were constructed. Semi-empirical PM7 method was used for geometry optimization calculations. A total of 1,536 physicochemical properties were …
Valorization Of Furfural To Fuel Additives By Aluminophosphate And Metal-Organic Framework Catalysts, Janejira Ratthiwal
Valorization Of Furfural To Fuel Additives By Aluminophosphate And Metal-Organic Framework Catalysts, Janejira Ratthiwal
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, aluminophosphate (APAl) catalysts and metal oxide catalysts from calcined metal-organic frameworks (C-MOFs) were successfully synthesized. APAl-A catalysts were obtained from the FQM-383 laboratory group of Prof. Dr. Rafael Luque. The catalysts were named APAl-X/Y-A-Z which X/Y was the ratio of P/Al ratio and Z was the calcination temperature. Both factors were varied to study their effects on the catalyst properties of surface area and active acid sites on catalyst surface. The MOFs (MIL-101(Fe) and MIL-125(Ti)) were prepared by the solvothermal method. The calcination of MOFs (C-MIL-101(Fe) and C-MIL-125(Ti)) provided metal oxide catalysts. The APAl catalysts and C-MOFs …
Application Of Core Annular Flow For Oil Transportation In Different Pipe Configurations Using Computational Fluid Dynamics, Cindy Dianita
Application Of Core Annular Flow For Oil Transportation In Different Pipe Configurations Using Computational Fluid Dynamics, Cindy Dianita
Chulalongkorn University Theses and Dissertations (Chula ETD)
The application of Core Annular Flow (CAF) has become an interesting solution in transporting heavy oil through pipeline because of its energy reduction and cost efficiency. Current study conducted a 3D computational fluid dynamic (CFD) to simulate CAF of oil-water in horizontal T- and Y-pipe junctions with two types of oil characteristic i.e., oil as Newtonian fluid and oil as non-Newtonian Carreau Fluid. The 2k factorial statistical experimental design was applied to investigate the effect of geometry on the flow performance. Eight cases were run with different diameter combinations and junction angle. The most attractive design was measured by the …
Improving Chromatographic Analysis Of Phenolic Compounds, Tarika Lomcharoenwong
Improving Chromatographic Analysis Of Phenolic Compounds, Tarika Lomcharoenwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Phenolic compounds are important chemicals and are applied in many fields. Moreover, they are found as contaminants in the environment. This research aimed to improve the chromatographic analysis of phenolic compounds and was divided into two parts. The first part focused on improving the separation of a mixture containing eighteen phenols using gas chromatography with derivatized cyclodextrin stationary phases. Results showed that all three cyclodextrin-based stationary phases, with different ring sizes, improved the separation of the mixture in comparison to polysiloxane OV-1701 stationary phase. The best separation was obtained from the small-size alpha-cyclodextrin with a capillary column of 15-meter long …