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Articles 2281 - 2310 of 2554
Full-Text Articles in Engineering
Development Of Novel Electrocoagulation Reactor (Ecr) For Turbidity Removal And Decolorization From Textile Industry Wastewater, Penghour Hong
Development Of Novel Electrocoagulation Reactor (Ecr) For Turbidity Removal And Decolorization From Textile Industry Wastewater, Penghour Hong
Chulalongkorn University Theses and Dissertations (Chula ETD)
High concentration of dyes together with turbidity were frequently found in the effluents of textile industry wastewater, which are the toxic substances. To remove these contaminants, the combination between electrocoagulation process (EC) and separation has been proposed in this study. The objective of this present work is to design and evaluate the new electrocoagulation reactor (ECR) for treating dye and turbidity from synthetic textile wastewater. The optimization of electrode configuration and design parameter were examined with the batch column reactor for containing 4 liters of wastewater. The result showed that monopolar arrangement within the inner gap 1.5 cm and current …
Study Of Gas-Liquid Absorption In Terms Of Bubble-Fluid Hydrodynamic And Mass Transfer Parameter: Liquid Phase And Gas Phase, Prajak Sastaravet
Study Of Gas-Liquid Absorption In Terms Of Bubble-Fluid Hydrodynamic And Mass Transfer Parameter: Liquid Phase And Gas Phase, Prajak Sastaravet
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focus on study the effect of continuous system on the bubble hydrodynamic and mass transfer parameters (Qg, QL, DBd, UBd a, kL and kLa). The experiment were set up in a cylindrical acrylic column with 0.15 m inside diameter and 1 m in height. ILALR was setup an acrylic plate for liquid recirculation. Moreover, mass transfer determination, liquid phase was removed dissolved oxygen by using sodium sulphite (Na2SO3). The bubble hydrodynamic mechanisms are investigated by the high speed camera (100 images/sec) and image analysis program is used to determine the bubble hydrodynamic parameters. The bubbles are generated by …
Coal Combustion Products Utilization For Soil Amendment, Tran Thi Anh Tuyet
Coal Combustion Products Utilization For Soil Amendment, Tran Thi Anh Tuyet
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, coal has a crucial role in generating energy all over the world. As a result, the consumption of coal creates a huge amount of coal combustion products, including bottom ash and fly ash. The coal ash has the potential characteristics to become a resource material in agriculture such as its texture, water holding capacity, bulk density, pH etc., and contains almost all the essential plant nutrients. However, most of the coal ash created is dumped into the landfill, which is a contributing factor in the environmental degradation. This study wants to use coal ash in agriculture as a way …
Time Series Pattern Discovery Techniques For Well-To-Well Log Correlation, Chanchai Apiwatsakulchai
Time Series Pattern Discovery Techniques For Well-To-Well Log Correlation, Chanchai Apiwatsakulchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Well log data is one of the most abundant data sources for subsurface characterization since almost all drilled wells are logged. Subsurface characterization requires correlated well log information. Processes to help perform well-to-well log correlation have been developed in this study based on the two approaches: pattern matching and pattern discovery. Pattern matching focuses on finding a known pattern of interest in uncorrelated wells. The use of Euclidean, Hamming, and Levenshtein distances in similarity measurement, Piecewise Aggregate Approximation (PAA), and Symbolic Aggregate approXimation (SAX) data representation helps create reduced-resolution while maintains the main characteristics of the signals. Multi-resolution analysis provides …
Classification Models For Stocks' Performance Prediction: A Case Study In Stock Exchange Of Thailand (Set), Athit Phongmekin
Classification Models For Stocks' Performance Prediction: A Case Study In Stock Exchange Of Thailand (Set), Athit Phongmekin
Chulalongkorn University Theses and Dissertations (Chula ETD)
Within stock market, the objective of both stock buyers and sellers is to make profit on price difference based on their expectation on a company's current and future value. There is no investing strategy that is considered to be the best by experts, and investing decision criteria remain contingent upon an individual investor's experiences and bias. To address the challenges, this paper uses financial ratios and company's industry data to construct forecasting models that quantitatively describe the return on stock investment. Various classification models, including Logistic Regression (LR), Decision Tree (DT), Linear Discriminant Analysis (LDA) and K-nearest neighbor are used …
Increasing Profit By Rice Export Reduction Among Union Members, Narabhatra Sangmanacharoen
Increasing Profit By Rice Export Reduction Among Union Members, Narabhatra Sangmanacharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
Over the past decades, OPEC which coordinates petroleum policies among members has agreed to cut supply to raise oil price. With a consensus elasticity of -0.13, oil is an inelastic commodity, a reduction in production results in a huge increase in price. It is noticeable that OPEC can increase oil price because they altogether possess a large amount of global oil supply. It is interesting whether this strategy can be used with rice to increase its price by reducing its supply. Because rice elasticity ranges between -0.51 and -0.13, rice is also an inelastic commodity. Although rice and oil have …
Synthesis And Properties Of Acrylonitrile-Butadiene-Styrene Copolymer Containing Silica Nanoparticles, Charungkit Chaikaew
Synthesis And Properties Of Acrylonitrile-Butadiene-Styrene Copolymer Containing Silica Nanoparticles, Charungkit Chaikaew
Chulalongkorn University Theses and Dissertations (Chula ETD)
The aim of this research is to develope acrylonitrile butadiene styrene composite reinforced with hydrophobic silica nanoparticles. In this study, in-situ synthesis of ABS rubber particles containing hydrophobic silica nanoparticles (HDTMS-silica) was carried out. Firstly, three of HDTMS-silicas (HDTMS-silica1, HDTMS-silica2, and HDTMS-silica3) were prepared by silanization of SiO2 nanoparticle with hexadecyltrimethoxysilane (HDTMS : SiO2 wt ratios of 1 : 1, 2 : 1, and 3 : 1) in an emulsion system. Then, HDTMS-silica/styrene and acrylonitrile mixture was fed into a polybutadiene latex reactor. Following that, graft copolymerization was carried out using persulfate initiator at temperature of 65 oC for 3.5 …
Surface Modification Of Microcrystalline Cellulose From Parawood Sawdust Via Mechanochemical Process For Reinforcement In Polypropylene Composites, Patcharaporn Chuayplod
Surface Modification Of Microcrystalline Cellulose From Parawood Sawdust Via Mechanochemical Process For Reinforcement In Polypropylene Composites, Patcharaporn Chuayplod
Chulalongkorn University Theses and Dissertations (Chula ETD)
The objective of this study is to prepare and modify parawood microcrystalline cellulose (PW-MCC) for applying as reinforced material for polypropylene composites. PW-MCC was prepared from parawood sawdust using acid hydrolysis method with pulp to acid ratio at 1:15 and temperature at 80oC for 2 hours. The obtained PW-MCC exhibited the cellulose type I with CrI at 60%. Moreover, PW-MCC had higher thermal stability than parawood sawdust. PW-MCC was further modified with various types of coupling agent such as maleic anhydride-grafted-polypropylene (PP-G-MA), organosilane, and acid chloride. Vinyltrimethoxysilane and three different acid chlorides such as benzoyl chloride, hexanoyl chloride, and lauroyl …
Comparision Of Fly Ash And Metakaolin Based Geopolymer Properties For Heavy Metal Adsorption, Sujitra Onutai
Comparision Of Fly Ash And Metakaolin Based Geopolymer Properties For Heavy Metal Adsorption, Sujitra Onutai
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work aims to evaluate the effectiveness of fly ash and metakaolin based geopolymer powder and fly ash and metakaolin based geopolymer composite fiber as an adsorbent for removal of heavy metal ions from aqueous solution. The fly ash and metakaolin used as raw materials in this research was from Thailand. Fly ash based geopolymer (FAG) was synthesized by mix with an alkali solution. After that, the geopolymerization process was occurred and then cured geopolymer samples at 60oC for 24 h and left at 25 oC for 6 days. The fly ash based geopolymer was ground, washed and sieved through …
Design And Control Of A 2-Dof Rehabilitation Robot With A Task Defined In A Virtual Environment., Natthapong Angsupasirikul
Design And Control Of A 2-Dof Rehabilitation Robot With A Task Defined In A Virtual Environment., Natthapong Angsupasirikul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research proposes a novel upper-limb rehabilitation robotic system. Instead of an exoskeleton type, the proposed robot is designed as active 2-DOF end-effector type moving in a horizontal plane, with being compact and easy to use with the harmless image. The rehabilitation robot system consists of a robot, a controller system and a virtual environment (game). The proposed rehabilitation robot system has been evaluated with 2 healthy subjects. The robot system has been evaluated in passive, active non-assist and active intent-based assistive rehabilitation type.
Design And Development Of An Assistive Hand Device For Enhancing Compatibility And Comfortability, Siwakorn Toochinda
Design And Development Of An Assistive Hand Device For Enhancing Compatibility And Comfortability, Siwakorn Toochinda
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, there are plenty of hand exoskeletons for rehabilitation and assistive purpose that have been developed. They have been designed for working with patient's limbs and can be used for hand positioning and executing task which help reduce therapist's workload and gives them an alternative way to rehabilitate patients. However, there are some patients with permanent impairment which cannot improve from rehabilitation further. Thus, portable assistive devices could greatly help them performing simple activities of daily living (ADL), but such device has not been fully explored yet, the present design of tendon routing cannot closely replicate finger orientation and motion …
Theoretical Studies On Electronic Properties Of Curved Graphene Quantum Dots And Lithium Adsorption On Graphene Quantum Dots, Naruwan Pattarapongdilok
Theoretical Studies On Electronic Properties Of Curved Graphene Quantum Dots And Lithium Adsorption On Graphene Quantum Dots, Naruwan Pattarapongdilok
Chulalongkorn University Theses and Dissertations (Chula ETD)
Graphene quantum dots (GQDs), with their attractive properties, are of interest to apply for electronic devices. Therefore, this dissertation aimed to investigate the electronic of curved graphene quantum dots (CGQDs) and the adsorption of lithium on GQDs. For the first part, two shapes of flat GQDs, rhomboidal (RGQDs) and hexagonal (HGQDs), were modified to make CGQDs with different folding axes and angles. Stabilities and electronic properties of CGQDs were studied using PBE/DNP. The results showed that the deformation energies of GQDs depend on sizes and folding axes but not their shapes. HOMO-LUMO gap variations, both widening and narrowing the gap, …
Development Of Data Acquisition Technique For Computed Tomography Of Simplified Distillation Column Model As Used In Petroleum And Petrochemical Plants, Dhanaj Saengchantr
Development Of Data Acquisition Technique For Computed Tomography Of Simplified Distillation Column Model As Used In Petroleum And Petrochemical Plants, Dhanaj Saengchantr
Chulalongkorn University Theses and Dissertations (Chula ETD)
This dissertation propose the development of data acquisition technique for computed tomography of simplified distillation column model as used in petroleum and petrochemical industries. The aim of this dissertation is to apply the computed tomography technique to inspect the internal structure of distillation column regardless of complex system to move radiation detectors and source. The developed data acquisition technique allows the operator to move radiation detectors and radiation source by follow designed algorithm. The scanning data are reconstructed using filtered back projection algorithm to evaluate internal structure at the region of interest from cross sectional reconstructed image. In this dissertation, …
Development Of Technique For Screening Liquids In Unopened Bottle Using Low Energy X-Ray Transmission, Parkphum Orachorn
Development Of Technique For Screening Liquids In Unopened Bottle Using Low Energy X-Ray Transmission, Parkphum Orachorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Since August 2006 after the discovery of terrorists' attempts to explode airplanes with liquid explosives in United Kingdom, each airline passenger is allowed to carry only a maximum of 100 ml liquid in each container and a total of not more than 1,000 ml in carry-on luggage. This measure was adopted to prevent bringing sufficient amount of fuel oil, alcohol, hydrogen peroxide or other flammable and explosive liquids into the aircraft. In this research, X-ray transmission technique was experimentally investigated using low energy X-rays between 13.6 - 43.5 keV emitted from 238Pu radioisotopic source and linear attenuation coefficient of liquids …
Assisted Methane Hydrate Formation With The Addition Of Promoters, Chutikan Jaikwang
Assisted Methane Hydrate Formation With The Addition Of Promoters, Chutikan Jaikwang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Natural gas hydrates play an important role in the largest reservoir of hydrocarbons on earth. The gas hydrates have received increasing attention in an excellent way of new technology for gas in large quantity storage and transportation. However, the main challenge to use methane hy¬drates has faced many challenges such as the slow formation rate, low growth rate during hydrate formation, and low conversion ratio of gas to solid hydrates leading to poor storage capacity. In this work, methane hydrate formation and dissociation in the presence of different Cyclopentane (CP), Tetra-n-butyl phosphonium bromide (TBPB) and Tetra-n-butyl ammonium bromide (TBAB) concentrations …
Microbial Conversion Of Cellulose To Sugars By Bacterial Enzyme, Kessara Seneesrisakul
Microbial Conversion Of Cellulose To Sugars By Bacterial Enzyme, Kessara Seneesrisakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This work studied the conversion of lignocellulosic materials to sugars, the intermediates for bioethanol production, by a bacterial enzyme. Due to the complex structure of lignocellulose, a cellulase enzyme cannot effectively access and hydrolyse cellulose fibers. Various pretreatment processes of lignocellulose have been studied to enhance enzymatic hydrolysis to date. In this work, corncob was firstly studied for microbial pretreatment using three microorganisms including two bacterial strains of Bacillus subtilis A 002 and Cellulomonas sp. TISTR 784 and a fungal strain of Phanerochaete sordida SK7. The results showed that the microbial pretreatment with P. sordida SK7 was the most effective …
Effects Of Bead Size And Concentration Of Unstable Asphaltenes Obtained From Different Centrifugation Techniques On Asphaltene Deposition In Packed Bed Apparatus, Kimchhay Lao
Chulalongkorn University Theses and Dissertations (Chula ETD)
Asphaltenes are the heaviest and most polar fraction of petroleum crude oil. They are the collection of components that can be soluble in aromatics solvents such as benzene or toluene, but insoluble in normal alkanes, n-pentane, n-hexane, or n- heptane. Asphaltenes are a class of molecules consisted of grouped aromatic rings with alkane chains. Changing pressure, temperature, composition, and shear rate during transportation can cause precipitation and deposition, resulting in reduced reservoir productivity due to restricted flow lines, fouling and blockages in the pore spaces of the reservoir. The goal of this investigation is to assess validity of two aspects …
Adsorptive Bubble Separation For Oil Removal, Paweena Kanokkarn
Adsorptive Bubble Separation For Oil Removal, Paweena Kanokkarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This present work emphasized on the current knowledge regarding (i) feasibility of multi-stage forth flotation operation for oil removal, and (ii) comprehension of dynamic surface tensions of surfactant solutions in relation to foam characteristics. A multi-stage forth flotation efficiency depends on the enhancement of interfacial adsorption and the number of bubble caps and tray. The operational parameters including foam height, air flow rate and feed flow rate were controlled to obtain the optimum process performance. Under the optimum conditions—a number of trays of 4, a foam height of 60 cm, an air flow rate of 40 L/min, a feed flow …
Investigation Of Asphaltene Aggregation Kinetics In The Presence Of Water-In-Oil Emulsion, Penpitcha Roengsamut
Investigation Of Asphaltene Aggregation Kinetics In The Presence Of Water-In-Oil Emulsion, Penpitcha Roengsamut
Chulalongkorn University Theses and Dissertations (Chula ETD)
Asphaltene is a component of the petroleum liquid defined operationally. It represents the most refractory (or the heaviest fraction). It is well-known that changes in temperature, pressure, or composition can destabilize asphaltenes and cause aggregation and deposition in porous formations, production lines, and processing facilities (Sheu and Mullins 1995). This leads to the study of the behavior of asphaltene aggregation and parameters that could affect the rate of aggregation which, in this case, is water-in-oil emulsion. In addition, the asphaltene aggregation model derived by Haji-Akbari (2013) is applied as a framework in this study which explains the correlation between the …
Study On Energy Storage Ability Of Zno/Tio2 For Photocatalytic Degradation Of Isopropanol, Ratchawan Jarumanee
Study On Energy Storage Ability Of Zno/Tio2 For Photocatalytic Degradation Of Isopropanol, Ratchawan Jarumanee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The photocatalytic degradation of isopropanol under UV irradiation was studied by using p-n junction of ZnO/TiO2 photocatalysts prepared by sol-gel technique. Their energy storage ability was tested with their photocatalytic activity where there was no UV illumination. That was investigated by illumination the system with UV light for 2 h and off for 2 h until 8 h. The composition and surface structure of the catalyst were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), surface area analysis, and particle size analysis. The change in the isopropanol concentration was observed by using gas chromatography. The result showed that the …
Vegetable Oil Based Microemulsion Biofuels, U-Larak Peson
Vegetable Oil Based Microemulsion Biofuels, U-Larak Peson
Chulalongkorn University Theses and Dissertations (Chula ETD)
The growth of energy demand increases dramatically which has resulted in an increase of exhaust emissions to air quality deterioration. Therefore, there are driving forces in the development of renewable energy production technologies. Vegetable oils based reverse micelle microemulsions have been increased in attention for biofuel production. This work aims to formulate microemulsion biofuel containing palm oil/diesel blend as nonpolar phase, and ethanol/butanol, as a polar phase. The nonionic alcohol ethoxylate surfactant with the different numbers of EO groups, EOn (n=1, 3, 5, and 9) were selected as a stabilizing agent. A pseudo-ternary phase diagram was conducted to determine an …
Improvement Of Life Cycle Assessment Software And Its Applications, Yodsathorn Chavewanmas
Improvement Of Life Cycle Assessment Software And Its Applications, Yodsathorn Chavewanmas
Chulalongkorn University Theses and Dissertations (Chula ETD)
LCSoft is Life Cycle Assessment (LCA) software which developed for perform LCA together with process design. It is a stand-alone tool with ability to be integrated with other process design tools such as process simulation software (PROII/ASPEN), economic analysis tool (ECON), and sustainable process design tool (SustainPro). In addition, several optional interpretation features are available such as, sensitivity analysis, alternative comparison, and eco-efficiency evaluation. In this research, LCSoft had been improved in performance and application range. The development framework consisted of four tasks. The first task deals with improvement of LCI and LCIA calculation which new pathway for calculation and …
Methane Adsorption By Carbon Molecular Sieve Derived From Polycarbonate And Polyaniline, Jakchai Thawornwatthanasirikul
Methane Adsorption By Carbon Molecular Sieve Derived From Polycarbonate And Polyaniline, Jakchai Thawornwatthanasirikul
Chulalongkorn University Theses and Dissertations (Chula ETD)
The adsorptions of methane by carbon molecular sieves (CMS) were investigated at 35°C and 45°C by volumetric apparatus with the pressure range from 0 to 800 psia. CMS was prepared from polymer precursors such as polycarbonate (PC) and polyaniline (PANI) by carbonization under nitrogen inert atmosphere and activation by CO2 at temperature 700, 800 and 900°C. The yield of CMS is decreased with increasing carbonization and activation temperature. The methane adsorption capacity at 35°C of CMS derived from PC is 2.82 mmol CH4/g. The methane adsorption of the samples from PC is higher than those obtained from PANI for the …
Effect Of Oxygen-Containing Functional Groups On Methane Adsorption By Activated Carbon, Kittima Dheerapreampree
Effect Of Oxygen-Containing Functional Groups On Methane Adsorption By Activated Carbon, Kittima Dheerapreampree
Chulalongkorn University Theses and Dissertations (Chula ETD)
Natural gas has been applied as a fuel for vehicle because it is cheaper and cleaner burning than other fuels. In the vehicle, natural gas is ordinarily reserved by compressing and storing under high pressure at room temperature but this method has several limitations (e.g. low energy density, high weight of tank). Therefore, a porous material with high specific surface area (e.g. activated carbon) is suggested to eliminate the limitations of natural gas storage by compression, natural gas is adsorbed at relatively low pressure and room temperature. The adsorption capacity of activated carbons is related with their physical and chemical …
The Incipient Layer Of Wax Deposit, Tunya Ketjuntiwa
The Incipient Layer Of Wax Deposit, Tunya Ketjuntiwa
Chulalongkorn University Theses and Dissertations (Chula ETD)
The formation of the incipient layer of wax deposit when waxy oil is exposed to a cold surface is studied. Using a cold-finger apparatus, the evolution of deposit thickness is monitored with a video camera, allowing one to resolve the deposit layer formation from inception up to long times where deposit thickness no longer times where deposit thickness no longer grows. Characterization of wax deposits show that incipient layer has identical composition to waxy oil, indicating that deposit is not formed by a diffusion process. Modelling shows deposit formation at the investigated conditions cannot be explained by a diffusion process.
Material Flow Analysis (Mfa) Study For Sustainable Management Of Pvc Wastes In Thailand (Phase Iii), Wikanda Khomchu
Material Flow Analysis (Mfa) Study For Sustainable Management Of Pvc Wastes In Thailand (Phase Iii), Wikanda Khomchu
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polyvinyl chloride (PVC) products are used for domestic consumption more than 400,000 tons annually and tend to be increasing in Thailand. After discarded, these products will become wastes which are being accumulated and could cause several environmental problems if they are disposed by inappropriate method. In previous studies, our group investigated the material flow of PVC in Thailand to handle the PVC waste problems. Material Flow Analysis (MFA) model was developed to estimate the quantity and route of PVC wastes in Thailand. Furthermore, the primary data were collected from recycle shops and landfill sites were used to estimate the amount …
Catalytic Activity Study Of Nixsny Intermetallics, Anchernsiri Noomnual
Catalytic Activity Study Of Nixsny Intermetallics, Anchernsiri Noomnual
Chulalongkorn University Theses and Dissertations (Chula ETD)
Cinnamyl alcohol (COL), versatile chemical in fragrance, flavoring, and pharmaceutical industries, can be found in only small amounts in nature. Generally, COL can be synthesized via selective hydrogenation of cinnamaldehyde (CALD), natural oil, at aldehyde functional group under high pressure of hydrogen gas. In this work, NixSny intermetallics were used as catalysts in selective hydrogenation to obtain COL. These catalysts were synthesized via mechanical alloying, economic and environmental method, and characterized by X-ray diffraction (XRD). By using 43, 58, and 75% tin contents with nickel, Ni3Sn, Ni3Sn2, and Ni3Sn4 intermetallics were prepared, respectively. In addition, formic acid was used as …
Electrical Property-Investigation Of Porous Clay Heterostructures Derived From Naturally-Occurring Clay Minerals For Smart Packaging, Kornkamol Srithammaraj
Electrical Property-Investigation Of Porous Clay Heterostructures Derived From Naturally-Occurring Clay Minerals For Smart Packaging, Kornkamol Srithammaraj
Chulalongkorn University Theses and Dissertations (Chula ETD)
Porous Clay Heterostructure (PCH) is an interesting material to use as entrapping system such as ethylene scavenger, respected to its high surface area with uniform and specific pore size. PCHs have been prepared by the surfactant-directed assembly of mesostructured silica within the two-dimensional galleries of clays. Then, the PCH was synthesized within the galleries of Na-bentonite clay by the polymerization of tetraethoxysilane (TEOS) in the presence of surfactant micelles. In addition, mesoporous clay with organic-inorganic hybrid (HPCH) is modified via co-condensation reaction of TEOS with candidate conductive functional groups (thiol group) and metal loading (silver), designated as MPPCH and Ag-PCH, …
Study The Best Support For Hydrolysis Of Tiger Grass, Kurizara Sayamnikorn
Study The Best Support For Hydrolysis Of Tiger Grass, Kurizara Sayamnikorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Bioethanol, one of the outstanding biofuels, is not only a renewable bio-based resource, but also interesting to research for improving better properties of the enzyme needed in the hydrolysis process. The purpose of this work is to study how to reuse the enzyme used in the hydrolysis step for bioethanol production by immobilizing Trichoderma reesei (T.reesei) on various silica supports, namely, SBA-15, TUD-1, and MCM-48. The amount of the adsorbed enzymes was determined by UV-visible spectrophotometry. Among those studied supports, SBA-15 showed 100% enzymatic adsorption on the support owing to its larger pore diameter of 6.14 nm, which is large …
Development Of Pedot-Pss/Zeolite Composite As A Gas Sensor, Pojjawan Chanthaanont
Development Of Pedot-Pss/Zeolite Composite As A Gas Sensor, Pojjawan Chanthaanont
Chulalongkorn University Theses and Dissertations (Chula ETD)
Composites with Poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonic acid), PEDOT-PSS, as the matrix containing zeolites of various Si/Al ratios in the range of 23-280 were fabricated to investigate the effect of Si/Al ratios on electrical conductivity sensitivity responses towards the target gas. The electrical conductivity responses of PEDOT-PSS/Zeolite composites were altered due to the available adsorption sites for gas molecules. The addition of zeolites to the pristine PEDOT-PSS improves the electrical conductivity sensitivity of the composites by enhancing the interaction between PEDOT-PSS and target gas. Composites with PEDOT-PSS matrix containing faujasite zeolites type Y were fabricated to investigate the effects of …