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Techno-Economic Analysis Of Succinic Acid Production From Sugarcane Molasses, Apitsada Rongsawad
Techno-Economic Analysis Of Succinic Acid Production From Sugarcane Molasses, Apitsada Rongsawad
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study proposes an alternative approach to address global warming concerns by introducing bio-based succinic acid production derived from molasses and waste CO2 in ethanol production as a substitute for conventional petroleum-based methods. The evaluation focuses on the downstream process; reactive extraction, aiming to assess its feasibility in terms of technical, economic, energy, and CO2 emission performance. The results indicate that the integrated process, Int. ETOH+SA 25:75, exhibits remarkable benefits, including a 66% reduction in CO2 emissions from ethanol production, a 77% decrease in energy consumption compared to petroleum-based methods, and NPV of 2,180 million USD with a 40.81% IRR …
Techno-Economic And Environmental Assessment For Enhancementbiodiesel Production Process Using Rotating Tube Reactor And Dry Washing, Arthit Jarungwongsathien
Techno-Economic And Environmental Assessment For Enhancementbiodiesel Production Process Using Rotating Tube Reactor And Dry Washing, Arthit Jarungwongsathien
Chulalongkorn University Theses and Dissertations (Chula ETD)
The study aims at exploring the potential use of rotating tube reactor (RTR) and performing economic analysis as wells as addressing the challenges associated with the utilization of different feedstocks including of refined palm oil (RPO) and waste cooking oil (WCO) for biodiesel production. The type of feedstock strongly influenced the optimum reaction temperature. For instance, RPO can produce biodiesel in the RTR at room temperature while WCO required the external heat source for biodiesel production at 65°C. In addition, two transesterification steps of WCO were required to achieve 95.16%. Simulation results found that the process intensification using RTR and …
Enzymatic Pretreatment Of Rice Bran Acid Oil Before Γ-Oryzanol Recovery, Asdarina Binti Yahya
Enzymatic Pretreatment Of Rice Bran Acid Oil Before Γ-Oryzanol Recovery, Asdarina Binti Yahya
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aims to apply enzymatic reactions for pretreating the major byproduct of rice bran oil (RBO) industry, rice bran acid oil (RBAO) before γ-oryzanol recovery. RBAO contains free fatty acids (FFAs), glycerides, and is rich in the super-antioxidant, γ-oryzanol. As a primary step to recover γ-oryzanol from RBAO, glycerides must be removed because of having similar polarity with γ-oryzanol. This study is conducted in two parts, hydrolysis and esterification/transesterification. In the first part, enzymatic hydrolysis. The study evaluates the performance of operating conditions using one factor at a time (OFAT) on the reaction time, temperature, lipase loading, water:RBAO ratio, …
Development Of Bioplastic Composite Films With Improved Antimicrobial Properties: A Comparative Study Between Blown Film Extrusion, Doctor Blading And Spray Coating, Atiwit Singhapan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P3HB4HB) is a bioplastic that has gained attention as a potential alternative to petroleum-based plastics in film packaging due to its good barrier properties and thermal stability. However, poly(3-hydroxybutyrate-co-4-hydroxybutyrate) has no outstanding properties. Therefore, the researcher added lignin powder to improve its antimicrobial properties, another essential property of the packaging film. This work successfully prepared a composite bioplastic film between poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and lignin powder by forming through a blown film extrusion, doctor blading, and spray coating. In order to give the film a high surface energy and enable it to adhere to the lignin solution on the surface, the …
Glycerol Carbonate Production From Glycerol And Diethyl Carbonate: A Comparative Study Between A Separated Reaction/Distillation (Srd) Process And A Reactive Distillation (Rd) Process, Chayanin Sriharuethai
Glycerol Carbonate Production From Glycerol And Diethyl Carbonate: A Comparative Study Between A Separated Reaction/Distillation (Srd) Process And A Reactive Distillation (Rd) Process, Chayanin Sriharuethai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Glycerol carbonate is one of the valuable products that can be converted from glycerol produced in the biodiesel industry. In this work, the continuous process of glycerol carbonate production via transesterification from crude glycerol and diethyl carbonate will be developed using Aspen Plus simulation. There are two processes to be considered. First, the separated reaction/distillation (SRD) process consists of a continuously stirred tank reactor for the reaction section and a distillation column for the purification section. Second, the reactive distillation (RD) process consists of a reactive distillation column that can accommodate both the reaction and purification in a single column, …
Parameters Optimization In Chlor-Alkali Ion-Exchange Membrane Electrolysis Process With Artificial Neural Network, Kittapas Sukantowong
Parameters Optimization In Chlor-Alkali Ion-Exchange Membrane Electrolysis Process With Artificial Neural Network, Kittapas Sukantowong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Since ion-exchange membrane electrolysis cell has developed for producing Chlor-Alkali products. New higher efficiency and lower consumption technology are released from licensors yearly, which made the process correlation deviate from the original design. The machine learning is used with “Neural Network Fitting Tool (nftool)” in MATLAB. To find a correlation between 5 inputs consisting of current density (CD, KA/m2), operation day (DOL, day), feed brine flow rate (QFB, m3/h), feed caustic flow rate (QHD, m3/h), cell temperature (T, degC) and one output which is cell voltage (CV, V). Datasets were collected from the plant information management system “exaquantum” historian database. …
Economic Evaluation Of Ethyl Lactate Production Via Reactive Distillation At Different Concentrations Of Lactic Acid, Nattapat Klin-U-Bol
Economic Evaluation Of Ethyl Lactate Production Via Reactive Distillation At Different Concentrations Of Lactic Acid, Nattapat Klin-U-Bol
Chulalongkorn University Theses and Dissertations (Chula ETD)
Ethyl lactate is a green solvent made from agricultural crops, making it more environmentally friendly than petrochemical solvents. The product is obtained via esterification of lactic acid with ethanol over Amberlyst-15 acid catalyst in a reactive distillation column. In commercial-scale production of ethyl lactate, this work designs production processes at two concentrations of lactic acid (50 and 85 wt.%) and two ethanol feed temperatures (25 and 85 °C). Highly concentrated lactic acid can result in adverse effects, such as increased oligomers and reduced desired products, making a comprehensive simulation of the production process necessary to evaluate energy consumption, economics, and …
Simultaneous Reaction And Separation Technologies For Biodiesel Production Derived From Alternative Feedstocks, Nattawat Petchsoongsakul
Simultaneous Reaction And Separation Technologies For Biodiesel Production Derived From Alternative Feedstocks, Nattawat Petchsoongsakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focused on the production of biodiesel using hybridized reactive distillation (hybridized RD) and centrifugal contractor reactor (CCR) from waste cooking oil (WCO) to reduce the operating cost. However, WCO contains some water which can cause saponification. The study showed that using two heat exchangers with hybridized RD is a simple method for water removal but it required the highest energy and cost (1.63 $/kg biodiesel). The extended spacing stage for water removal required a new hybridized RD construction with additional spacing stages. This method can handle and require less energy, resulting in lower cost (1.07 $/kg biodiesel). The …
Sulfur-Tolerant Cobalt-Doped La0.3sr0.7tio3-D-Perovskite Cathode For Intermediate-Temperature Solid Oxide Electrolysis Cell, Natthamon Nuengjumnong
Sulfur-Tolerant Cobalt-Doped La0.3sr0.7tio3-D-Perovskite Cathode For Intermediate-Temperature Solid Oxide Electrolysis Cell, Natthamon Nuengjumnong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Lanthanum doped strontium titanate (LST) is a perovskite cathode in Solid Oxide Electrolysis Cell (SOEC) which shows great performance in syngas production from CO2 and steam feed. However, the LST type cathode suffers from structural stability. Sulfur containing in industrial exhaust gas can affect its durability which inhibit the technology in real application. Therefore, to improve sulfur tolerance, La0.3Sr0.7Ti1-yCoyO3-δ (LSTC) by adding Co2+ metal ion at B-site when y is 0 to 20%mol was synthesized. Citrate acid-nitrate combustion method was used and the synthesized powder. LST and La0.3Sr0.7Ti0.9Co0.10O3-δ (LSTC0.10) exhibited single phase perovskite while La2O3 and La(OH)3 were observed in …
Ethylene Polymerization With Zirconocene Catalyston Zeolite A Support Derived From Fly Ash, Natthapat Warintha
Ethylene Polymerization With Zirconocene Catalyston Zeolite A Support Derived From Fly Ash, Natthapat Warintha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Zeolite A (LTA) synthesis from fly ash has many applications, in which metallocene catalytic support is uncommon. This research study has three parts. Firstly, investigation of the effects of immobilized MAO cocatalyst and zirconocene catalyst techniques on silica support. Immobilized MAO, followed by metallocene catalyst method had the highest catalytic activity, which was used in the next parts. The second part examined the optimal temperature and [Al]MAO/[Zr]cat ratio with ethylene polymerization in a semi-batch autoclave reactor utilizing LTA-supported metallocene catalysts. The optimal conditions were found at 80°C and [Al]MAO/[Zr]cat ratios equal to 2000 that were used in the next section. …
Characteristics And Catalytic Properties Of Copper On Mcf-Si And Sba-15 For Hydrogenation Of Carbon Dioxide, Sirimas Suelueam
Characteristics And Catalytic Properties Of Copper On Mcf-Si And Sba-15 For Hydrogenation Of Carbon Dioxide, Sirimas Suelueam
Chulalongkorn University Theses and Dissertations (Chula ETD)
At present, the production of methanol from the hydrogenation of carbon dioxide is widespread. The current popular catalysts include copper oxide, zinc oxide and aluminum oxide (CZA) catalysts. As the reaction progresses, the catalyst forms coke. This causes the efficiency of the catalyst to decrease. In this study, the copper catalyst on the mesoporus silica support was investigated. This type of support has high thermal stability. Cu catalysts were synthesized on MCF-Si and SBA-15 supports with different pore morphology such as spherical and hexagonal shape, respectively, by wetness impregnation (W) method and incipient wetness impregnation (IW) with a copper loading …
Comparison Of Techno-Economic Analysis Of 1,3-Propanediol Production From Crude Glycerol Via Chemical And Biological Methods, Sivatchaya Boriboon
Comparison Of Techno-Economic Analysis Of 1,3-Propanediol Production From Crude Glycerol Via Chemical And Biological Methods, Sivatchaya Boriboon
Chulalongkorn University Theses and Dissertations (Chula ETD)
At present, the biodiesel industry is expanding rapidly which could lead to an oversupply of the by-product, crude glycerol. To manage this, crude glycerol should be converted into value-added chemicals such as 1,3-propanediol (1,3-PDO). In this study, the production of 1,3-PDO via catalytic reaction is simulated using a process simulator to evaluate its techno-economic performance as well as its environmental impact. The obtained results will be compared with the conventional production of 1,3-PDO to point out the advantages that the catalytic reaction can offer in terms of economic, energy utilization, raw material utilization, and environmental impacts.
Scale Up Of Benzoxazinone Derivative Synthesis In Batch Reactor, Sumate Boonkird
Scale Up Of Benzoxazinone Derivative Synthesis In Batch Reactor, Sumate Boonkird
Chulalongkorn University Theses and Dissertations (Chula ETD)
Benzoxazinone derivative is one of starting materials in the synthesis of Deferasirox (a Chelating iron for thalassemia patient). The parameters of Benzoxazinone derivative synthesis were investigated from the condensation of salicylic acid, salicylamide, cyanuric chloride, and triethylamine using toluene as solvent. The mole equivalent ratio of salicylic acid: salicylamide:cyanuric chloride:triethylamine at 1:1:0.67:1 provided the 46.77% yield of Benzoxazinone derivative in laboratory scale. Surprisingly, 4-chloro-2-(2-hydroxyphenyl)-4H-benzo[e][1,3]oxazine-4-ol was observed in the synthesis of Benzoxazinone derivative. In addition, the reaction scheme of Benzoxazinone derivative synthesis was proposed as a model for the study of the chemical kinetic constant. Furthermore, the scale up of Benzoxaxinone …
Effects Of Zinc Oxide On Thermal, Mechanical, Morphological, And Gas Barrier Properties Of Polybutylene Succinate/ Poly(3-Hydroxybutyrate-Co-4-Hydroxybutyrate) Films, Sunisa Suwatthi
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, conventional polymers from petrochemical processes have low biodegradability and remain in the environment for several hundred years. This has negative effects on the environment. This research aims to improve the properties of biopolymers such as poly(butylene succinate) (PBS) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P3HB4HB). P3HB4HB was selected to blend with PBS in with weight ratios of PBS:P3HB4HB was 90/10 and ZnO nanoparticles (0.5, 1 and 2%) was selected as a nucleating agent. The melt blending process using an internal mixer and molded into a film using a compression molding process. The chemical structures, morphological properties, thermal properties, dynamic mechanical properties, mechanical properties …
Control Of A Polybutylene Succinate (Pbs) Polymerization In A Semi-Batch Reactor By Neural Network Model Based Predictive Controller, Takorn Plengsangsri
Control Of A Polybutylene Succinate (Pbs) Polymerization In A Semi-Batch Reactor By Neural Network Model Based Predictive Controller, Takorn Plengsangsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polybutylene succinate (PBS) is a biodegradable plastic known for its strength and versatility in various applications. This research presents a data-driven approach to simulate temperature control in a semi-batch reactor during polymerization, the performance of the proposed approaches was compared against conventional controllers, including PID control and first-principles model MPC control. The study developed neural network model-based predictive control (NNMPC) and multiple neural network model-based predictive control (Multi-NNMPC), using Python and Tensorflow. Neural network models were trained by using a wide range of dynamic data with varying numbers of neurons in hidden layers to investigate the process dynamics under different …
Design Of Process For Recovery Of Gold And Nickel Ions From Wastewater Of Metal Plating Process In Electronics Industry Using Hollow Fiber Supported Liquid Membrane, Wanchalerm Srirachat
Design Of Process For Recovery Of Gold And Nickel Ions From Wastewater Of Metal Plating Process In Electronics Industry Using Hollow Fiber Supported Liquid Membrane, Wanchalerm Srirachat
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the manufacture of printed circuit boards (PCBs), electroless nickel immersion gold (ENIG) plating is widely applied. During the plating process, excess nickel and gold plating solutions, which adheres to the workpiece, is removed. As a result, economical quantities of nickel and gold ions accumulate in the rinse water baths and can then be collected. In this work, the simultaneously selective extraction and recovery of nickel and gold ions using a single-step operation of hollow fiber supported liquid membrane (HFSLM) technique was studied. Real rinse wastewater from the plating process containing trace nickel ions (Ni(II)) of 15 mg/L and gold …
The Study Of Weave-Pattern Effect On Filtration Performance Of Woven Filter Cloths By Computational Fluid Dynamic Modeling, Wisit Bandasak
The Study Of Weave-Pattern Effect On Filtration Performance Of Woven Filter Cloths By Computational Fluid Dynamic Modeling, Wisit Bandasak
Chulalongkorn University Theses and Dissertations (Chula ETD)
An important global problem that has an impact on both human health and the environment is air pollution. Exercise and outdoor activities are essential for human well-being, but they can also have a detrimental effect on health and the environment. For example, PM2.5 and PM10 particles can enter the lungs and cause respiratory and cardiovascular disorders. Moreover, masks must be worn in order to stop the COVID-19 epidemic from spreading. Nevertheless, not all masks are effective in preventing viruses and air pollution. Consequently, selecting the proper mask is essential for avoiding health risks. Using the use of computational fluid dynamics, …
Improvement Of Hydrodynamics And Heat Transfer In Biomass Fluidized Bed Combustor With Immersed Tubes Using Cfd-Dem, Krittin Korkerd
Improvement Of Hydrodynamics And Heat Transfer In Biomass Fluidized Bed Combustor With Immersed Tubes Using Cfd-Dem, Krittin Korkerd
Chulalongkorn University Theses and Dissertations (Chula ETD)
Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) has been extensively utilized for studying hydrodynamics and heat transfer in fluidization processes. This study specifically focuses on improving hydrodynamics and heat transfer in a biomass fluidized bed combustor with immersed tubes. The investigation involves the use of mixed biomass, exploring the effects of biomass types, biomass loading, and blending ratios to propose criteria for selecting suitable biomass fuel for the system. Design parameters related to the immersed tubes, such as the angle between tubes, tube diameters, and distance between tubes, were also considered. A data-driven model was developed based on …
Chemical Constituents From The Fresh Pericarps Of Mature Mangosteen Fruit Garcinia Mangostana, Ahmad Tijani Azeez
Chemical Constituents From The Fresh Pericarps Of Mature Mangosteen Fruit Garcinia Mangostana, Ahmad Tijani Azeez
Chulalongkorn University Theses and Dissertations (Chula ETD)
α-Mangostin has been identified as a major chemical constituent in the pericarps of mangosteen (Garcinia mangostana Linn.) Over time, dried pericarps of mangosteen have been subjected to studies in literature. This study aimed to explore isolation of α-mangostin and other chemical constituents from the fresh pericarps of mature mangosteen fruits and investigate their relative antioxidant and anticancer activities. Repeated column chromatography on ethyl acetate and methanol extracts of fresh mature mangosteen pericarps led to the isolation of α-mangostin (33.25% of crude extracts) as the major compound, beta-mangostin (0.225%) and gartanin (7.57%). Their antioxidant scavenging activity was investigated against 2,2-diphenyl-1-picrylhydrazyl (DPPH) …
Simultaneous Extraction And Colorimetric Detection Of Ions Using Gel Electromembrane, Ali Sahragard
Simultaneous Extraction And Colorimetric Detection Of Ions Using Gel Electromembrane, Ali Sahragard
Chulalongkorn University Theses and Dissertations (Chula ETD)
A total integrated electrocolorimetric sensing approach consisting of gel-based electromembrane extraction and colorimetric detection in one-step process was developed. This system was designed using colorimetric reagents preadded to the agarose gel for the determination of the following two model analytes: iodide for negative ions and nickel for positive ions. In this system, when a voltage was applied, the analytes were extracted and transferred from the sample solution (donor phase) to the gel (acceptor phase). The analytes then simultaneously reacted with the colorimetric reagents inside the gel, yielding blue and pink colors for iodide and nickel ions, respectively. These colors were …
Fluorescent Hydrazine-Naphthalimide Encapsulated By Ethyl Cellulose For Detection Of Long-Chain Aldehydes, Faiza Lawan Isah
Fluorescent Hydrazine-Naphthalimide Encapsulated By Ethyl Cellulose For Detection Of Long-Chain Aldehydes, Faiza Lawan Isah
Chulalongkorn University Theses and Dissertations (Chula ETD)
One of the most common diseases globally which takes numerous lives is lung cancer. The high concentrations of aldehydes found in tobacco smoke and motor vehicle exhaust are among the contributors for lung cancer. There is a lot of interest in developing a nanosensor for identifying long-chain aldehydes. The conventional methods for detecting aldehyde are highly complex, expensive, and time-consuming. To overcome this drawback, alternative detection techniques such as fluorescence techniques are needed for the quick, easy, and affordable identification of aldehydes. Aldehyde molecules and their derivatives are often used as biomarkers to aid in the diagnosis and treatment of …
Deep Eutectic Solvent-Coated Paper-Based Device For Colorimetric Detection Of Chromium(Vi), Fakhry Gripaldi Pandu
Deep Eutectic Solvent-Coated Paper-Based Device For Colorimetric Detection Of Chromium(Vi), Fakhry Gripaldi Pandu
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hexavalent chromium, Cr(VI), is one of the heavy metal ions often found in the environment that is highly toxic and classified as a carcinogen. In this work, rapid screening and onsite monitoring of Cr(VI) using paper-based has been developed. Furthermore, a natural-based deep eutectic solvent, comprising choline chloride and thymol that makes it an environmentally friendly solvent, is applied as a coating medium on the test strips for qualitative and quantitative analysis of Cr(VI) for the first time. 1,5-Diphenylcarbazide was used as an indicator and complexing agent for Cr(VI). The detection was conducted by using a smartphone equipped with an …
Use Of Layered Double Hydroxides As Ionophore For Anion Selective Electrode, Kittipong Konraeng
Use Of Layered Double Hydroxides As Ionophore For Anion Selective Electrode, Kittipong Konraeng
Chulalongkorn University Theses and Dissertations (Chula ETD)
Layered double hydroxides (LDHs) or hydrotalcite compounds are referred to anionic clays with specific anion adsorption and exchanging properties. These behaviors are similar to ionophores and ionic additives in ion selective electrodes (ISEs). Therefore, in this study LDHs was used to function as tailor-made ionophores for particular anions and ionic additives in ISEs. MgAl LDHs were prepared, and then modified the intercalated anions to be NO3-. The selective polymeric membrane was casted using PVC and MgAl LDHs-NO3-. The membrane containing 30%(w/w) MgAl LDHs-NO3- showed the best ISE characteristics toward NO3- with response slopes of -51.31 mV decade-1 in the concentration …
Colorimetric Detection Of Norfloxacin And Ceftazidime By Modified Materials, Lalitphan Hongtanee
Colorimetric Detection Of Norfloxacin And Ceftazidime By Modified Materials, Lalitphan Hongtanee
Chulalongkorn University Theses and Dissertations (Chula ETD)
Novel approaches were developed for the colorimetric detection of norfloxacin and ceftazidime using chemically modified polymer resin and cotton sponge as sensing materials, respectively. For norfloxacin detection, the optimum condition was achieved by using a resin modified with 6.0 µM Congo red at pH 6 to extract norfloxacin in 10 mL of sample at pH 2. The reaction was completed within 15 minutes. Regarding ceftazidime detection, a cotton sponge functionalized with polyethyleneimine (PEI) was fabricated and characterized by FTIR, SEM, and ninhydrin test. To fabricate the PEI-sponge, 170 mM 3-aminopropyl triethoxysilane (APTES) was used to modify 1.0 g cotton fibers …
Nickel Complexes Containing N4 Schiff-Base Macrocycles Dereived From Diphenylamine-2,2'-Dicarboxaldehyde For Catalytic Co2 Reduction, Methasit Juthathan
Nickel Complexes Containing N4 Schiff-Base Macrocycles Dereived From Diphenylamine-2,2'-Dicarboxaldehyde For Catalytic Co2 Reduction, Methasit Juthathan
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this dissertation, nickel(II) complexes featuring N4-Schiff base macrocycles derived from diphenylamine-2,2'-dicarboxaldehyde (1-Ni and 2-Ni) with a new crystal structure ([2-Ni]Me) were synthesized and investigated for electrochemical CO2 reduction (ECR). Cyclic voltammetry (CV) of two nickel complexes, 1-Ni and 2-Ni, illustrated the catalytic response whereas one, [2-Ni]Me, virtually remained peak-shaped in the presence of CO2, indicating the feasibility of ECR activity for these nickel complexes. To develop heterogeneous ECR catalysts in aqueous media, all nickel complexes were adhered on N-doped graphene (NG) through non-covalent interaction, obtaining Ni@NG hybrid catalysts. The Ni@NG catalysts showed satisfactory ECR activity with the faradaic efficiency …
Enhancement Of Ammonia Gas Sensing By Metal Oxide-Polyaniline Nanocomposite, Nattawut Soibang
Enhancement Of Ammonia Gas Sensing By Metal Oxide-Polyaniline Nanocomposite, Nattawut Soibang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Ammonia (NH3) gas is an important chemical in many industries. Employees who work in those industrial areas may exposed to a certain concentration of NH3 which could cause various symptoms such as irritation of skin and eyes and problems in respiratory system. The development of new NH3 sensing material has drawn a great attention. In this study, porous tin dioxide nanofibers (SnO2 NFs) were successfully fabricated by an electrospinning technique. The SnO2 NFs were composited with polyaniline (PANI), conducting polymer and form tin dioxide nanofibers@polyaniline nanocomposite (SnO2 NFs@PANI). The morphology was characterized using SEM-EDS and XRD. The SnO2 NFs@PANI was …
Emulsification Microextraction Using Surfactant Coupled With Colorimetric Detection For Determination Of Synthetic Dyes In Food, Niluh Indria Wardani
Emulsification Microextraction Using Surfactant Coupled With Colorimetric Detection For Determination Of Synthetic Dyes In Food, Niluh Indria Wardani
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this thesis, solidification of floating organic drop-emulsification liquid-liquid microextraction (SFOD-ELLME) was combined with digital image colorimetry (DIC) for the analysis of synthetic dyes, such as rhodamine B (RhB) and crystal violet (CV) in food and drink samples. Here, the extraction was performed by using emulsified fatty acid surfactant and freezing procedure to separate the extracting phase. The solidified floating organic drop was then taken out, liquified and dropped on the paper platform for digital image colorimetric analysis. The response surface methodology-central composite design (RSM-CCD) was used to optimize some variables that influence the extraction efficiency. A sample of 7 …
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 …
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 …
An Analytical Network Process (Anp) Model For Choosing Optimal Public-Private Partnership (Ppp) Contract Types For Infrastructure Projects, Su Lae Yee Zaw
An Analytical Network Process (Anp) Model For Choosing Optimal Public-Private Partnership (Ppp) Contract Types For Infrastructure Projects, Su Lae Yee Zaw
Chulalongkorn University Theses and Dissertations (Chula ETD)
With the rapid social and economic development, a great deal of expenditure is crucial for the nation's infrastructure development. Nevertheless, the governments of many developing nations have been experienced with the limited budget and technical inability to deliver effective public infrastructures. Public-private partnership (PPP) has been adopted as an alternative collaboration arrangement between the government and the private sector in many nations to overcome these challenges. PPP can be defined as a long-term contract between a public agency and a private entity for rendering public facilities, including design, construct, finance, operate, and manage the project. The PPP contract types can …