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M2 Macrophages In Human Periapical Lesions In Relation To Histopathological Diagnosis, Clinical Features, And Lesion Volume, Supanant Visarnta
M2 Macrophages In Human Periapical Lesions In Relation To Histopathological Diagnosis, Clinical Features, And Lesion Volume, Supanant Visarnta
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study evaluated M1 and M2 macrophage polarization in human periapical cysts and granulomas through an immunohistochemical analysis and investigated the correlation between the macrophage polarization and histopathological diagnosis, clinical features and lesion volume using cone-beam computed tomography. The periapical biopsies histopathologically diagnosed as radicular cyst (n=52) and periapical granuloma (n=51) were analyzed by immunohistochemical method. Immuno-expressions of CD68 and CD163 were quantified. The CD68/CD163 ratio was adopted to represent M1 or M2 macrophage polarization. Pathological diagnosis, patients’ age, gender, clinical signs and symptoms, tooth location of the periapical lesion, and history of root canal treatment were obtained from treatment …
Comparison Of Removal Torques Among Different Abutments In Single Implant Crowns After Cyclic Loading: An In Vitro Study, Suppanut Jongsiri
Comparison Of Removal Torques Among Different Abutments In Single Implant Crowns After Cyclic Loading: An In Vitro Study, Suppanut Jongsiri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Objectives: To evaluate the effect of different restoration designs on the removal torque loss of implant-supported maxillary first premolar crowns after cyclic loading and to measure the impact of cyclic loading on removal torque. Materials and Methods: Thirty-two dental implants (4.0*10 mm), embedded in resin blocks and their abutments, were divided into 4 groups (n=8) based on restoration design: screwmentable group, 2 cement-retained groups: cemented with adhesive resin cement (Panavia V5) or provisional cement (RelyX Temp NE), and screw-retained one-piece titanium group. Monolithic zirconia crowns were fabricated and cemented in the first three groups. Their removal torques were recorded using …
The Alleviating Effects Of Epidermal Growth Factor On An In Vitro Oral Mucositis Model In The Presence Of Fusobacterium Nucleatum, Tien Thi Trieu Truong
The Alleviating Effects Of Epidermal Growth Factor On An In Vitro Oral Mucositis Model In The Presence Of Fusobacterium Nucleatum, Tien Thi Trieu Truong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Objectives: 5-fluorouracil (5-FU) is commonly used as a chemotherapy drug for head and neck cancers. However, it often produces an adverse cytotoxic effect on the oral epithelia leading to oral mucositis (OM) in cancer patients. Thus, reversing this cytotoxic effect locally with novel bioactive drugs or factors is necessary. This study aimed to investigate the rescue effect of Nicotiana benthamiana plant-derived epidermal growth factor (P-EGF) on human normal oral keratinocytes (NOKs) exposed to 5-FU-induced cytotoxicity in the presence of Fusobacterium nucleatum (Fn). Materials and Methods: Cytotoxicity and ATP-dependent proliferation and metabolism of NOK monolayer cultures were assessed after 48 hours …
Equity In Maternal And Child Health In Myanmar: Benefit Incidence Analysis On Utilization Of Health Services, Myint Si Thu
Equity In Maternal And Child Health In Myanmar: Benefit Incidence Analysis On Utilization Of Health Services, Myint Si Thu
Chulalongkorn University Theses and Dissertations (Chula ETD)
Utilization of maternal and child health services plays a crucial role in preventing pregnancy related deaths and child deaths. High levels of maternal and child mortalities are remaining as public health problems in Myanmar. Therefore, this study aims to examine the effects of socio-economic and geographical factors on utilization of maternal and child health services at public health facilities in Myanmar, and analyze the levels of benefit that go to the people in different wealth status. Secondary data analysis is conducted using maternal and child health data from Myanmar Demographic and Health Survey (MDHS) 2015- 16. Marginal effects of multinomial …
Factors Influencing Mode Choice Selection And Intention Of Public Transport Users : A Comparative Study Between Thailand And Indonesia During Pandemic, Aditya Mahatidanar Hidayat
Factors Influencing Mode Choice Selection And Intention Of Public Transport Users : A Comparative Study Between Thailand And Indonesia During Pandemic, Aditya Mahatidanar Hidayat
Chulalongkorn University Theses and Dissertations (Chula ETD)
The COVID-19 pandemic significantly impacted public transportation, causing a substantial decline in bus passengers. In 2021, Bangkok witnessed a 40-60% reduction compared to normal conditions, while Jakarta experienced a staggering 76% decline compared to June 2019. This study aims to assess passengers' intentions to use buses during the pandemic and analyze factors influencing mode choice. Two methodologies were employed: the Structural Equation Model (SEM) to identify factors impacting transportation intentions and the Hybrid Choice Model (HCM) to understand mode choice influencers. Data collection occurred in Bangkok and Jakarta, targeting bus users at central transportation hubs, with 392 and 387 respondents. …
Techno-Economic Analysis And Intensification Of Biosurfactant Production From Palm Fatty Acid For Oil Recovery Enhancement, Chanapol Charoentanaworakun
Techno-Economic Analysis And Intensification Of Biosurfactant Production From Palm Fatty Acid For Oil Recovery Enhancement, Chanapol Charoentanaworakun
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, Biosurfactants are receiving the interest as a substitute for surfactants synthesized from petroleum products due to their biodegradability. Palm oil derivatives are one of the interesting candidates of biosurfactant production because of the superior properties of hydrocarbon structure in the range of C16-C18. Thus, this research studied the economic and environmental impact analysis of production processes, and adsorption and oil recovery performance for different anionic biosurfactants synthesized from palm oil derivatives, i.e. palm fatty acid distillate (PFAD). Moreover, the optimal design and essential operating condition of batch reactive distillation column were also studied to intensify the equilibrium limitation of …
A Machine Learning Predictive Model For The Extension Of Operation Time And The Operation Cost Overrun : A Case Study Of Vietnamese Bot-Ppp Transportation Projects, Pham Van Hoai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Public-Private Partnership (PPP) projects in Vietnam's transportation sector are vital for infrastructure development but frequently encounter significant risk factors (RFs) during the operation phase. These RFs often lead to the extension of operation time (EOPT) and operation cost overruns (OPCO), undermining project success and investor returns. Despite the importance of the operation phase, most research has focused on the project feasibility and construction stages, with limited attention given to the operation phase. This research fills this gap by developing predictive models to manage the EOPT and OPCO caused by RFs during the operation phase of Build-Operate-Transfer (BOT) transportation projects in …
Biomarkers Of Mild Cognitive Impairment With And Without Depression In The Elderly, Gallayaporn Nantachai
Biomarkers Of Mild Cognitive Impairment With And Without Depression In The Elderly, Gallayaporn Nantachai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Amnestic Mild Cognitive Impairment (aMCI) is the deterioration of cognitive function, where those with the amnestic subtype have memory decline and may conversion to Alzheimer’s disease. This study is both a systematic review and meta-analysis on 3.798 MCI individuals and 6.063 healthy controls and a case-control study. The case-control study included 121 MCI and normal volunteers aged 60-75. Collectively, the dissertation aimed to explore the relationship between biomarkers, psychological symptoms, and neuropsychological assessment in MCI. Descriptive statistics were used to describe the general data set, while meta-statistics were used to review biomarkers. The predictive relationship of various factors in MCI …
Genetic Heterogeneity Of Glucose 6-Phosphate Dehydrogenase (G6pd) Regulatory Region In G6pd Deficient Patients, Lawrence Billy Vasco Djama
Genetic Heterogeneity Of Glucose 6-Phosphate Dehydrogenase (G6pd) Regulatory Region In G6pd Deficient Patients, Lawrence Billy Vasco Djama
Chulalongkorn University Theses and Dissertations (Chula ETD)
G6PD deficiency is a genetic disorder caused by either suboptimal function of the G6PD enzyme or instability of the G6PD gene, resulting in insufficient production of the G6PD protein. This study investigates mutations in the regulatory regions of the G6PD gene using Nanopore MinION sequencing, as mutations outside the coding region can also affect G6PD activity. Blood samples from 89 individuals (73 adults and 16 newborns) with G6PD deficiency or intermediate levels but unidentified coding sequence mutations were analyzed. Genomic DNA was screened for mutations, enriched using degenerate oligonucleotide-primed PCR (DOP-PCR), and sequenced using the Oxford MinION platform. Bioinformatic analyzes …
The Diagnostic Accuracy Of Maxillary Fungal Ball Rhinosinusitis In Paranasal Sinus Computed Tomography Using Deep Learning Models, Pakapoom Sukswai
The Diagnostic Accuracy Of Maxillary Fungal Ball Rhinosinusitis In Paranasal Sinus Computed Tomography Using Deep Learning Models, Pakapoom Sukswai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Purpose: This study aimed to assess the accuracy of deep learning models for the diagnosis of maxillary fungal ball rhinosinusitis (MFB) in paranasal sinus computed tomography and to compare the accuracy, sensitivity, specificity, precision, F1-score with thoses of rhinologists. Methods: We collected all adult chronic rhinosinusitis (CRS) patients who underwent paranasal sinus cone-beam computed tomography (CT) in the Department of Otolaryngology, King Chulalongkorn Memorial Hospital (KCMH), Thailand between 2014 and 2021. Cone-beam CT images were constructed and labeled to form the deep learning models from overall dataset consisted of 254 maxillary fungal ball (MFB) cases and 1285 other CRS subtypes …
Accuracy Of 177lu Quantification For Dosimetry Calculation Using 12-Swiveling Czt Detectors Spect/Ct Camera, Panattha Damthongsen
Accuracy Of 177lu Quantification For Dosimetry Calculation Using 12-Swiveling Czt Detectors Spect/Ct Camera, Panattha Damthongsen
Chulalongkorn University Theses and Dissertations (Chula ETD)
Recently, the 12-cadmium zinc telluride (CZT) based digital detectors SPECT/CT system has been introduced for advanced technology in nuclear medicine instrument, which outperforms conventional cameras. Moreover, the voxel S value-based dosimetry is important and offers more accurate in personalized dosimetry treatment using targeted radionuclide therapy. This study aimed to determine the accuracy of 177Lu quantification through an IEC/NEMA phantom study and to evaluate total-body dosimetry in patients undergoing 177Lu therapy using 12-swiveling digital CZT detectors SPECT/CT camera. The NEMA/IEC body phantom inserted with six fillable spheres (10-, 13-, 17-, 22-, 28-, and 37-mm inner diameter), filled with 177Lu solution of …
Gardenia Jasminoides Fruit Extract Alleviates Non-Steroidal Anti-Inflammatory Drug–Induced Gastropathy In Rats, Rinrada Worapongpaiboon
Gardenia Jasminoides Fruit Extract Alleviates Non-Steroidal Anti-Inflammatory Drug–Induced Gastropathy In Rats, Rinrada Worapongpaiboon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Non-steroidal anti-inflammatory drug (NSAID)-induced gastropathy is a health burden that requires effective treatment. Gardenia jasminoides fruit extract (GJE) protects the gastrointestinal tract by reducing inflammation with wide safety margins, but the underlying mechanisms are still indeterminate. Therefore, this thesis aimed to explore the effects of GJE pretreatment on NSAID-induced gastric injury in rats based on the hypothesis that GJE could attenuate the injury. Twenty-four male Sprague Dawley rats were assigned to 3 groups (n=8/group). The control group received a vehicle (7.5% NaHCO3). The NSAIDs group received indomethacin 200 mg/kg twice a day (4 hours apart) for 2 consecutive days. The …
Mycobacterium Spp. Identification By Nanopore Technology, Samitanan Sunantawanit
Mycobacterium Spp. Identification By Nanopore Technology, Samitanan Sunantawanit
Chulalongkorn University Theses and Dissertations (Chula ETD)
Tuberculosis is caused by infection with Mycobacterium tuberculosis (MTB). Although TB and non-tuberculous mycobacteria (NTM) infection exhibit similar symptoms, their treatments differ significantly. NTM strains need a specific drug regimen and some NTM strains are resistant to anti-TB drugs. Hence, mycobacterial identification is crucial. At present, the culture-based technique is the gold standard in mycobacterium detection, but it is time-consuming (3-6 weeks). Here, this study aimed to develop mycobacterial amplicon-based nanopore sequencing (Myco-ANS) assay for the differentiation of eight reference strains of mycobacteria, as well as to assess the diagnostic accuracy of Myco-ANS compared with reference line probe assay for …
Self-Medication In Children Population: A Systematic Review And Meta-Analysis, Aye Chan Nyein Thinn
Self-Medication In Children Population: A Systematic Review And Meta-Analysis, Aye Chan Nyein Thinn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Self-medication is defined by the World Health Organization (WHO) as the use of medicines to treat self-recognized symptoms or ailments without consulting a physician. Self-medication practice was found among children either self-practice or with caregiver assistance. This study aimed to assess the prevalence and patterns of self-medication practice in children. This study utilized systematic review and meta-analysis by searching papers published during 2013 to 2022 in PubMed, ScienceDirect, Scopus, and Embase. The two sets of keywords “children” and “self-medication” or “non-prescription” were used. It was found that 4,333 articles were retrieved. After inclusion-exclusion screening, 83 articles were included in the …
Factors Influencing Disposal Methods Of Unused Medicines: A Systematic Review, Guu Nandar Chit
Factors Influencing Disposal Methods Of Unused Medicines: A Systematic Review, Guu Nandar Chit
Chulalongkorn University Theses and Dissertations (Chula ETD)
Objective: This systematic review aimed to describe how people store and dispose of unused and expired medicines, explore the extent of proper storage and disposal and examine factors influencing these behaviors. A comprehensive search of five databases, PubMed, Scopus, Springer Link, Science Direct, and EBSCO. The QualSyst assessment tool was applied to evaluate the quality of the included studies. The review encompassed 55 eligible studies from 27 countries, involving 31,246 participants. The refrigerator was the most common storage location (40% average) while discarding in household trash was the universal disposal method. Medicine storage at home ranged from 17.9% to 97%, …
Polycationic Colicin N Inhibits Metastatic Activity In Human Lung Cancer Cells Through Suppression On Epithelial To Mesenchymal Transition, Lwin Lwin Aye
Chulalongkorn University Theses and Dissertations (Chula ETD)
Colicins are bacterial toxins, produced by E. coli under stressed conditions to kill other related strains of bacteria. Among other bacteriocins, colicin N is pore-forming bacteriocin which has cytotoxic activity on human lung cancer H460 cells. Polycationic (supercharged) colicin N (CoIN+12) is structurally engineered colicin N with more positive charges, on receptor binding domain of which, aspartic and glutamic acids were replaced by six lysine residues. It has been reported that polycationic colicin N has higher cytotoxic activity in human lung cancer cells. However, anti-metastatic effect of polycationic colicin N on human lung cancer cells has not been investigated. In …
Identification Of Active Region Of Colicin N Translocating Domain Involved In Its Antibacterial Activity, Wanassanan Lampromkaew
Identification Of Active Region Of Colicin N Translocating Domain Involved In Its Antibacterial Activity, Wanassanan Lampromkaew
Chulalongkorn University Theses and Dissertations (Chula ETD)
Colicins are bacteriocins produced by Escherichia coli (E. coli) and toxified themselves. In general, colicins comprise three domains, including the N-terminal domain or translocation (T) domain, the Receptor binding (R) domain, and the Cytotoxic (C) domain. The combination of these domains produces different types and activities of colicin. Colicin N is the smallest colicin and functioned in pore-formation by the C-domain on the E. coli membrane. The antimicrobial activity is regulated by the specific binding between OmpF and TolA (as receptor and translocator) at region OBS (OmpF binding site) and TABs (TolA binding site), respectively. They are then inserting the …
Characteristics And Color Varieties Of Spinels From Main Deposits, Boonyapak Aksorn
Characteristics And Color Varieties Of Spinels From Main Deposits, Boonyapak Aksorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigates the characteristics and color variations of spinels from main deposits, including Liolava in Madagascar, Tunduru in Tanzania, Mogok in Myanmar, and three deposits in Vietnam (Minh Tien, Lang Chap, and An Phu). These spinel samples are categorized into four color varieties, i.e., red, orange, blue, and purple. All samples yielded the common properties of spinels. In addition, most red and orange spinels display strong red fluorescence under long wave ultraviolet (LWUV) and short wave ultraviolet (SWUV) lamps, however, some orange spinels exhibit non-fluorescence to red fluorescence under SWUV lamps. Blue spinel displays non-fluorescence under LWUV and SWUV …
Development Of Electrochemical Biosensor For Detection Of Thyroid–Stimulating Hormone, Kittirat Kitticharoenwiwat
Development Of Electrochemical Biosensor For Detection Of Thyroid–Stimulating Hormone, Kittirat Kitticharoenwiwat
Chulalongkorn University Theses and Dissertations (Chula ETD)
This dissertation focused on the development of electrochemical paper-based immunosensor for determining thyroid-stimulating hormone (TSH) using a label-free immunoassay. Thyroid-stimulating hormone is a pituitary hormone that stimulates the thyroid gland to produce thyroid hormones for the body’s metabolism. The current electrochemiluminescence method for determining TSH as a specific biomarker indicating congenital hypothyroidism (CHT) onset is unfortunately restricted to laboratory settings, thereby resulting in limited practical utilization, delayed diagnosis, and severe outcomes. Herein, we proposed a simple, rapid, portable, and sensitive electrochemical biosensor with a label-free format based on bovine serum albumin (BSA)/graphene oxide (GO) nanocomposite for TSH determination. Caboxylated GO …
Identification And Functional Characterization Of Mads-Box Proteins And Ccos Involved In Carotenoid Metabolism In Durian Durio Zibethinus L. Pulps, Kittiya Tantisuwanichkul
Identification And Functional Characterization Of Mads-Box Proteins And Ccos Involved In Carotenoid Metabolism In Durian Durio Zibethinus L. Pulps, Kittiya Tantisuwanichkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Durian (Durio zibethinus L.), known as the "King of fruits," holds significant economic importance in Thailand. Apart from its unique odor and sweet taste, durian pulp exhibits a yellow color, which is an important aspect of fruit quality. Carotenoids are essential compounds responsible for the yellow, orange, and red coloration in many fruits and vegetables. During durian fruit development and ripening processes, its pulp changes from white to yellow due to increased carotenoid accumulation. The carotenoid biosynthetic pathway, responsible for carotenoid production, is controlled by ethylene. However, the mechanism underlying this process in durian fruit is still unknow. Notably, the …
Bamboo Biochar For Bar Adsorptive Microextraction Of Parabens In Water, Maytinee Jantorn
Bamboo Biochar For Bar Adsorptive Microextraction Of Parabens In Water, Maytinee Jantorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, bamboo biochar bar was prepared in the form of small-sized rods using starch as a binder and applied as a sorbent in bar adsorptive microextraction (BAµE) of parabens (methyl paraben, ethyl paraben, propyl paraben and butyl paraben) in water. The mixture of bamboo biochar which has a size of 60-80 mesh, a surface area of 102.6 m²g-1 and a pore size of 0.7 nm and starch in a weight ratio of 1:13 gave the good mechanical stability and high removal efficiency of parabens. When applied the bamboo biochar bar as a sorbent, the optimum conditions for BAµE …
Selective Photodegradation Of Food Contaminants Using Titania-Silica-Iron Oxide Nanocomposites With Molecularly Imprinted Technology, Mehak Un Nisa
Selective Photodegradation Of Food Contaminants Using Titania-Silica-Iron Oxide Nanocomposites With Molecularly Imprinted Technology, Mehak Un Nisa
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study, magnetic imprinted photocatalysts (Fe3O4@SiO2@TiO2@MIP and Fe3O4@SiO2@MIP@TiO2) have been synthesized successfully by surface molecular imprinting technique. 5,7-dimethoxy-coumarin was used as a dummy template to give specific recognition ability to AFB1. A range of analytical techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), vibrating sample magnetometer (VSM), and Branauer-Emmett-Teller (BET) were employed to study the crystal structure, morphology, and chemical composition of the nanocomposites. The HPLC-DAD was used to quantify the photodegradation efficiency of imprinted photocatalysts under different factors such as the source of irradiation light, initial concentration of analyte, amount of photocatalyst, and …
Pea Protein Isolate As Emulsifier In Oil-In-Water Emulsion Model System, Mujahid Hassan Khan
Pea Protein Isolate As Emulsifier In Oil-In-Water Emulsion Model System, Mujahid Hassan Khan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Plant protein has been progressively demanded as a new-trend, healthier-choice and bioeconomic ingredient. However, the fundamental and technical knowledge of plant-based protein to understand and improve their structural functions are limited. In this study, pea protein isolate (PPI) were selected to be evaluated its emulsifying role on the formation, stability and tribology of model oil-in-water emulsions. Since PPI is a functional ingredient with hypoallergenic property. Firstly, the emulsifying property of PPI were investigated with corn oil-in-water emulsion systems. The results showed that 1% w/v PPI could stabilize the emulsion system of 5% w/v corn oil at pH7 using the high …
Crosslinking Enhancement Of Natural Rubber By Electron Beam, Mili Purbaya
Crosslinking Enhancement Of Natural Rubber By Electron Beam, Mili Purbaya
Chulalongkorn University Theses and Dissertations (Chula ETD)
Vulcanization is a crucial process that transforms raw rubber into a durable and useful material. During vulcanization, crosslinking points are created between rubber molecules, which convert them into a thermosetting substance. The conventional vulcanization method is carried out by the addition of some chemicals accompanied by the application of thermal energy. This study explored the possibility of using electron beam irradiation which is an environmentally friendly and short-time method for vulcanizing natural rubber. The research was divided into two parts. In the first part, the efficacy of electron beam vulcanization was compared to that of thermal vulcanization. Natural rubber containing …
Cellulose Nanofiber/Poly(Acrylic Acid)-Based Hydrogel For Colorimetric Biomarker Sensors, Nichaphat Passornraprasit
Cellulose Nanofiber/Poly(Acrylic Acid)-Based Hydrogel For Colorimetric Biomarker Sensors, Nichaphat Passornraprasit
Chulalongkorn University Theses and Dissertations (Chula ETD)
This dissertation develops innovative CNF/PAA hydrogel-based colorimetric sensors for non-invasive biomarker detection, focusing on urea for chronic kidney disease (CKD) and sarcosine for prostate cancer (PCa). Hydrogels serve as a matrix for enzyme and indicator encapsulation due to their high absorption capacity and unique three-dimensional network, with CNF enhancing mechanical properties. The research is divided into two parts. Part I involves preparing a GO/CNF/PAA hydrogel via non-toxic radiation crosslinking, featuring high swelling capacity and enhanced laser absorptivity due to GO. This hydrogel, used as a patch for on-skin detection, shows vivid color changes to distinguish CKD patients from healthy individuals, …
Polyaniline/Cellulose Nanofiber/Polyvinyl Alcohol Hydrogel-Modified Screen-Printed Graphene Electrode For Cd2+ And Ni2+ Detection, Pichapon Boonkrong
Polyaniline/Cellulose Nanofiber/Polyvinyl Alcohol Hydrogel-Modified Screen-Printed Graphene Electrode For Cd2+ And Ni2+ Detection, Pichapon Boonkrong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Heavy metal contamination in wastewater has been an environmental issue, so the determination of heavy metals by an accurate and simple method is important. In this work, polyaniline/cellulose nanofiber/polyvinyl alcohol hydrogel-modified screen-printed graphene electrode (PANI/CNF/PVA hydrogel-modified SPGE) was fabricated by combining the advantages of graphene and conductive hydrogel to increase the conductivity and preconcentrate the metal ions to fabricate the modified electrode for the simultaneous detection of Cd2+ and Ni2+. First, PANI/CNF nanocomposite was synthesized by in situ chemical polymerization, and CNF was shown to prevented PANI aggregation and provided sufficient porous structure on the modified electrode. The PANI/CNF nanocomposite …
Carbon-Based Polymer Composite For Electrochemical Sensing Of Creatinine Sodium Potassium And Calcium Ions, Kanyapat Teekayupak
Carbon-Based Polymer Composite For Electrochemical Sensing Of Creatinine Sodium Potassium And Calcium Ions, Kanyapat Teekayupak
Chulalongkorn University Theses and Dissertations (Chula ETD)
Electrochemical sensors have emerged as indispensable tools for various applications including environmental monitoring, food safety, and biomedical diagnostics owing to their simplicity, sensitivity, and fast response. However, traditional methods for electrode fabrication are often associated with drawbacks such as cleanroom requirements, multi-step processes involving toxic materials, high waste consumption, and high costs. To address the limitations, this dissertation evaluates the utilization of 3D printing, laser engraving, and inkjet printing technologies for the fabrication of electrochemical sensors based on carbon-based polymer composites. In the first part, a 3D-printed electrochemical sensor based on a copper oxide nanoparticle-ionic liquid/reduced graphene oxide (CuO-IL/rGO) modified …
Green Synthesis For Silver Nanoparticle /Natural Rubber/ Nanocellulose Bio-Polymeric Composites, Puttakhun Meemai
Green Synthesis For Silver Nanoparticle /Natural Rubber/ Nanocellulose Bio-Polymeric Composites, Puttakhun Meemai
Chulalongkorn University Theses and Dissertations (Chula ETD)
A green synthesis method was developed to produce biobased semiconducting composites of silver nanoparticles (AgNPs), skim natural rubber (SNR), and bacteria cellulose. A solution of silver nitrate (AgNO3) ranging from 40 to 160 mM was added to skim natural rubber latex (SNRL) to facilitate the reduction of silver ions to AgNPs at temperatures between 50 and 80 °C. Subsequently, BC pellicle was immersed in the prepared AgNPs-SNRL suspension for 48 hours, followed by washing and drying. The resulting AgNPs/SNR/BC films were then analyzed for their chemical, mechanical, antibacterial, and electrical properties. The strain at break of the films was significantly …
Bi-Directional Evolutionary Structural Optimization For 3d-Printed Prefabricated Concrete Panels, Pochara Amornsittipipat
Bi-Directional Evolutionary Structural Optimization For 3d-Printed Prefabricated Concrete Panels, Pochara Amornsittipipat
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis seeks to develop an optimal design methodology for 3D-printed prefabricated concrete panels. Although 3D-printed precast panels are advantageous for producing flexible forms, reducing workforce demand, and minimizing environmental impacts, the product must not be too heavy to transport and install. Therefore, the consideration of weight emphasizes the need for structural optimization. This research presents truss-like structural modeling based on the properties of 3D-printed concrete, suggests an optimal design methodology using the Bi-directional Evolutionary Structural Optimization (BESO) algorithm to achieve minimum weight, conducts parametric studies to understand the relationship between significant parameters and the optimal weight achieved, and demonstrates …
Development Of A Computer Vision System To Monitor Container Closures And Cleanliness Of Tools Related To Volatile Substances In Construction Projects, Tun Lin Naing
Chulalongkorn University Theses and Dissertations (Chula ETD)
Construction chemicals have gained an essential role across various aspects of the construction process in modern construction. While construction chemicals provide advantages to construction activities, if there are no control measures, they can transform into hazardous substances that pose occupational health risks and environmental impacts, which can also affect a company's ESG performance. Therefore, it is important to implement prevention and control measures for chemical materials during their utilization on construction sites to prevent the transformation of construction chemicals into hazardous substances. Currently, traditional methods of checking chemical containers and tools on construction sites are time-consuming, prone to errors, and …