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2023

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Health Risk And Ecological Risk Assessment From Microplastic Contamination In Sea Salt : Case Study In Ban Laem Salt Field, Phetchaburi, Thailand, Kusuman Promdontree Jan 2023

Health Risk And Ecological Risk Assessment From Microplastic Contamination In Sea Salt : Case Study In Ban Laem Salt Field, Phetchaburi, Thailand, Kusuman Promdontree

Chulalongkorn University Theses and Dissertations (Chula ETD)

Microplastics are ubiquitous in all terrestrial and aquatic environments. In this research, microplastic contamination in sea salt produced from traditional and plastic salt fields was studied. Including seawater used as a raw material for producing sea salt in Ban Leam salt fields, Phetchaburi, Thailand. Random samples were collected 3 replicates per point, for a total of 42 samples. 5M NaCl solution was used to separate the density and digest the organic substances using 0.05 M Fe (II) and 30% H2O2. The shape and color of the microplastics were characterized using a 30x magnification microscope. The amount, size, and polymer type …


Bolt Classification System For Motorcycle Retail Shop, Monchai Angkapiyasiri Jan 2023

Bolt Classification System For Motorcycle Retail Shop, Monchai Angkapiyasiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

The COVID-19 situation in Thailand has led to a rise in online purchase orders, resulting in a higher demand for using motorcycles for shipment, which has also increased the demand for essential components, notably durable and aesthetically pleasing bolts. To enrich their business opportunities, bolts of 19 classes are gathered from a motorcycle shop to establish a systematic bolt classification procedure containing feature extraction stage and classification stage. A feature extraction is formulated from utilization of steps, which are background removal, contour extraction, image rotation, cropping, structural analysis, dominant color analysis, hole detection, and calculating head-to-whole length ratio. Subsequently, five …


Electronic Resources Updates - 2022 Q4, Melanie Mcgurr, Gregg Harris Jan 2023

Electronic Resources Updates - 2022 Q4, Melanie Mcgurr, Gregg Harris

Electronic Resources Quarterly Updates

No abstract provided.


Data-Integrity Aware Stochastic Model For Cascading Failures In Power Grids, Rezoan Ahmed Shuvro, Pankaz Das, Jamir Shariar Jyoti, Joana M. Abreu, Majeed M. Hayat Jan 2023

Data-Integrity Aware Stochastic Model For Cascading Failures In Power Grids, Rezoan Ahmed Shuvro, Pankaz Das, Jamir Shariar Jyoti, Joana M. Abreu, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

The reliable operation of power grids during cascading failures is heavily dependent on the interdependencies between the power grid components and the supporting communications and control networks. Moreover, the system operators' expertise in dealing with cascading failures can play a pivotal role during contingencies. In this paper, a dynamical probabilistic model is developed based on Markov-chains, which captures the dynamics of cascading failures in the power grid. Specifically, a previously developed Markov-chain based model is extended to capture the trade-off between the benefits of having a robust communication infrastructure and its vulnerability from data integrity (e.g., cyber-attacks). State-space reduction of …


2+1 Roadway Design Guidance Update, Jeff Jasper, Jeff Wolfe, Robin Baskette, Paul Ross, Chris Van Dyke Jan 2023

2+1 Roadway Design Guidance Update, Jeff Jasper, Jeff Wolfe, Robin Baskette, Paul Ross, Chris Van Dyke

Kentucky Transportation Center Research Report

The frequency and severity of crashes on rural two-lane roadways have increased in the US relative to other road types. This trend can be explained by the growing number of vehicles, higher speeds, narrow shoulders, and vehicle mixes. One solution for improving traffic flow and safety outcomes on rural two-lane roadways is to adopt a 2+1 design, which confers the benefits of four-lane highways but at a lower cost. Transportation agencies throughout Europe — and increasingly the US — have seen good results from 2+1 layouts. Crash data from Sweden, Germany, Finland, and Denmark reveal better safety outcomes following the …


Pedestrian And Bicycle Improvement Scoring Method For Shift–2024, Nikiforos Stamatiadis, Daria Korostina, Teng Wang, Reginald Souleyrette Jan 2023

Pedestrian And Bicycle Improvement Scoring Method For Shift–2024, Nikiforos Stamatiadis, Daria Korostina, Teng Wang, Reginald Souleyrette

Kentucky Transportation Center Research Report

State transportation agencies have limited funding to deliver multimodal transportation programs that address the needs of all users. To allocate project funding in an impartial and objective manner, many agencies have adopted data-driven scoring systems that are used to evaluate the merits of proposed capital improvement projects. The Kentucky Transportation Cabinet introduced the Strategic Highway Investment Formula for Tomorrow (SHIFT) for this purpose. Until now SHIFT, has evaluated projects based five core variables — congestion, safety, benefit-cost ratio, asset management, economic growth. To address local needs, SHIFT has also allocated points that Area Development Districts, metropolitan planning organizations, and Cabinet …


The Function Of Histone Methylation And Acetylation Regulators In Gbm Pathophysiology, Colin Mccornack, Timothy Woodiwiss, Angela Hardi, Hiroko Yano, Albert H Kim Jan 2023

The Function Of Histone Methylation And Acetylation Regulators In Gbm Pathophysiology, Colin Mccornack, Timothy Woodiwiss, Angela Hardi, Hiroko Yano, Albert H Kim

2020-Current year OA Pubs

Glioblastoma (GBM) is the most common and lethal primary brain malignancy and is characterized by a high degree of intra and intertumor cellular heterogeneity, a starkly immunosuppressive tumor microenvironment, and nearly universal recurrence. The application of various genomic approaches has allowed us to understand the core molecular signatures, transcriptional states, and DNA methylation patterns that define GBM. Histone posttranslational modifications (PTMs) have been shown to influence oncogenesis in a variety of malignancies, including other forms of glioma, yet comparatively less effort has been placed on understanding the transcriptional impact and regulation of histone PTMs in the context of GBM. In …


Conserved Gene Signatures Shared Among Mapt Mutations Reveal Defects In Calcium Signaling, Miguel A Minaya, Sidhartha Mahali, Abhirami K Iyer, Abdallah M Eteleeb, Rita Martinez, Guangming Huang, John Budde, Sally Temple, Alissa L Nana, William W Seeley, Salvatore Spina, Lea T Grinberg, Oscar Harari, Celeste M Karch Jan 2023

Conserved Gene Signatures Shared Among Mapt Mutations Reveal Defects In Calcium Signaling, Miguel A Minaya, Sidhartha Mahali, Abhirami K Iyer, Abdallah M Eteleeb, Rita Martinez, Guangming Huang, John Budde, Sally Temple, Alissa L Nana, William W Seeley, Salvatore Spina, Lea T Grinberg, Oscar Harari, Celeste M Karch

2020-Current year OA Pubs

No abstract provided.


Prefrontal Network Engagement By Deep Brain Stimulation In Limbic Hubs, Anusha Allawala, Kelly R Bijanki, Denise Oswalt, Raissa K Mathura, Joshua Adkinson, Victoria Pirtle, Ben Shofty, Meghan Robinson, Matthew T Harrison, Sanjay J Mathew, Wayne K Goodman, Nader Pouratian, Sameer A Sheth, David A Borton Jan 2023

Prefrontal Network Engagement By Deep Brain Stimulation In Limbic Hubs, Anusha Allawala, Kelly R Bijanki, Denise Oswalt, Raissa K Mathura, Joshua Adkinson, Victoria Pirtle, Ben Shofty, Meghan Robinson, Matthew T Harrison, Sanjay J Mathew, Wayne K Goodman, Nader Pouratian, Sameer A Sheth, David A Borton

Faculty, Staff and Students Publications

Prefrontal circuits in the human brain play an important role in cognitive and affective processing. Neuromodulation therapies delivered to certain key hubs within these circuits are being used with increasing frequency to treat a host of neuropsychiatric disorders. However, the detailed neurophysiological effects of stimulation to these hubs are largely unknown. Here, we performed intracranial recordings across prefrontal networks while delivering electrical stimulation to two well-established white matter hubs involved in cognitive regulation and depression: the subcallosal cingulate (SCC) and ventral capsule/ventral striatum (VC/VS). We demonstrate a shared frontotemporal circuit consisting of the ventromedial prefrontal cortex, amygdala, and lateral orbitofrontal …


Perspectives On The Mission, Value And Impact Of The Business School, Howard Thomas, Howard Thomas Jan 2023

Perspectives On The Mission, Value And Impact Of The Business School, Howard Thomas, Howard Thomas

Research Collection Lee Kong Chian School Of Business

The business school has been an important success story in the evolution of the modern university. Yet it is increasingly valued in that context “much more for its managerial expertise, cash generation ability and financial strength than its intellectual vigour and scholarship. Indeed … its legitimacy as a serious academic discipline is critically questioned by scholars in science, arts and the humanities” (Thomas, Lorange and Sheth, 2013, pp 52/3). Rakesh Khurana (2007) argues that business schools have become the ‘hired hands’ of business and have abandoned any pretence of fulfilling goals of developing a cadre of professional managers as proposed …


Understanding Human-Centred Artificial Intelligence In The Banking Sector, Krishnaraj Arul Obuchettiar, Alan @ Ali Madjelisi Megargel Jan 2023

Understanding Human-Centred Artificial Intelligence In The Banking Sector, Krishnaraj Arul Obuchettiar, Alan @ Ali Madjelisi Megargel

Research Collection Lee Kong Chian School Of Business

The advent of smart digital devices and social media has shaped how consumers interact and transact with their financial institutions. Consumers increasingly want hyperpersonalised interactions that are more frequent and proactive, while financial institutions have a growing need to cater to consumers’ new demands. Financial institutions, such as banks, continuously adapt to the latest technologies to keep pace with evolving customer behaviours, needs, and experiences. One such emerging technology is artificial intelligence (AI). Many organisations realise the potential of AI; however, a human-centred AI system must be capable of understanding human characteristics and making decisions like humans. This paper presents …


Extended Kalman Filter Based Resilient Formation Tracking Control Of Multiple Unmanned Vehicles Via Game-Theoretical Reinforcement Learning, Lei Xue, Bei Ma, Jian Liu, Chaoxu Mu, Donald C. Wunsch Jan 2023

Extended Kalman Filter Based Resilient Formation Tracking Control Of Multiple Unmanned Vehicles Via Game-Theoretical Reinforcement Learning, Lei Xue, Bei Ma, Jian Liu, Chaoxu Mu, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

In This Paper, We Discuss the Resilient Formation Tracking Control Problem of Multiple Unmanned Vehicles (MUV). a Dynamic Leader-Follower Distributed Control Structure is Utilized to Optimize the Performance of the Formation Tracking. for the Follower of the MUV, the Leader is a Cooperative Unmanned Vehicle, and the Target of Formation Tracking is a Non-Cooperative Unmanned Vehicle with a Nonlinear Trajectory. Therefore, an Extended Kalman Filter (EKF) Observer is Designed to Estimate the State of the Target. Then the Leader of the MUV is Adjusted Dynamically According to the State of the Target. in Order to Describe the Interactions between the …


Averaged Behavior Model Of Current-Mode Buck Converters For Transient Power Noise Analysis, Anfeng Huang, Jingdong Sun, Hongseok Kim, Zhenxue Xu, Shuai Jin, Songping Wu, Zhiping Yang, Kelvin Qiu, Jun Fan, Chulsoon Hwang Jan 2023

Averaged Behavior Model Of Current-Mode Buck Converters For Transient Power Noise Analysis, Anfeng Huang, Jingdong Sun, Hongseok Kim, Zhenxue Xu, Shuai Jin, Songping Wu, Zhiping Yang, Kelvin Qiu, Jun Fan, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Accurate Evaluation and Simulation of Power Noise is Critical in the Development of Modern Electronic Devices. However, the Widely Used Target Impedance Fails to Predict the Low-Frequency Noise Generated in a Device Due to the Existence of the Dc–dc Converter, Whose Output Impedance Can Change under Different Loading Conditions. a Physical Circuit Model is Then Desired to Replicate the Behavior of a Voltage Regulator Module, and the Average Technique is an Efficient Method to Estimate the Noise of a Pulse Width-Modulated (PWM) Converter. with the Emergence of Converters with Adaptive On-Time (AOT) Controllers, More Complex Averaging Methods Are Required, But …


Conductive 3d Nano-Biohybrid Systems Based On Densified Carbon Nanotube Forests And Living Cells, Roya Bagheri, Alicia K. Ball, Masoud Kasraie, Aparna Chandra, Xinqian Chen, Ibrahim Miskioglu, Zhiying Shan, Parisa Pour Shahid Saeed Abadi Jan 2023

Conductive 3d Nano-Biohybrid Systems Based On Densified Carbon Nanotube Forests And Living Cells, Roya Bagheri, Alicia K. Ball, Masoud Kasraie, Aparna Chandra, Xinqian Chen, Ibrahim Miskioglu, Zhiying Shan, Parisa Pour Shahid Saeed Abadi

Michigan Tech Publications

Conductive biohybrid cell-material systems have applications in bioelectronics and biorobotics. To date, conductive scaffolds are limited to those with low electrical conductivity or 2D sheets. Here, 3D biohybrid conductive systems are developed using fibroblasts or cardiomyocytes integrated with carbon nanotube (CNT) forests that are densified due to interactions with a gelatin coating. CNT forest scaffolds with a height range of 120–240 µm and an average electrical conductivity of 0.6 S/cm are developed and shown to be cytocompatible as evidenced from greater than 89% viability measured by live-dead assay on both cells on day 1. The cells spread on top and …


The Effectiveness Of Using Facebook And Instant Communications Application (Line) To Reduce Alcohol Consumption Of Alcohol Promoters And Entertainers (Pretty Or Pr) In Bangkok, Thailand, Paladd Sakulthanit Jan 2023

The Effectiveness Of Using Facebook And Instant Communications Application (Line) To Reduce Alcohol Consumption Of Alcohol Promoters And Entertainers (Pretty Or Pr) In Bangkok, Thailand, Paladd Sakulthanit

Chulalongkorn University Theses and Dissertations (Chula ETD)

The deleterious health consequences associated with alcohol consumption, ranging from addiction and liver disease to accidents and mental health disorders, have been extensively documented. This study aimed to assess the efficacy of an educational program utilizing Facebook and Line platforms in mitigating alcohol consumption intentions among such workers in Bangkok. Utilizing a randomized controlled trial methodology, the study focused in Bangkok. A total of forty-four participants were allocated into either the intervention (n=22) or control (n=22) groups. The intervention group received health education sessions and live video broadcasts on Facebook, while the control group received standard care messages. Outcome measures …


Association Between Related Factors And Communication Channels Among Women With Abortion Service At Private Clinics In Thailand, Xiao Wang Jan 2023

Association Between Related Factors And Communication Channels Among Women With Abortion Service At Private Clinics In Thailand, Xiao Wang

Chulalongkorn University Theses and Dissertations (Chula ETD)

In February 2021, abortion was officially permitted in Thailand. In the delivery of abortion services, communication channel is a key factor in assisting clients to access services. Research on clients' choices of communication channels is important for increasing clients' access to legal abortion services. This secondary data cross-sectional study aims to identify the association between factors related to communication channels among the clients who receive abortion services at The Planned Parenthood Association of Thailand (PPAT)’s clinic. The study samples covered 3,734 clients who get abortion service at PPAT’s clinic from February 2021 to December 2022. The researcher employed socio-demographic characteristic, …


Development Of Probiotic Fermented Beverage From Gac Fruit (Momordica Cochinchinensis) And Its Functional Properties On Gut Health, Marisa Marnpae Jan 2023

Development Of Probiotic Fermented Beverage From Gac Fruit (Momordica Cochinchinensis) And Its Functional Properties On Gut Health, Marisa Marnpae

Chulalongkorn University Theses and Dissertations (Chula ETD)

The study aimed to develop a probiotic beverage using gac fruit and assess its characteristics and functional properties related to gut health through probiotic lactic acid fermentation. Gac juice (GJ) at 5–10 g/100 g was fermented with Lactobacillus paracasei subsp. paracasei (L. CASEI 431®), and various aspects were explored, including probiotic viability, physicochemical properties, phytochemicals, antioxidant activity, functional properties, volatile flavor compounds, and sensory acceptability of fermented GJ (FGJ). The results indicated a decrease in pH and sugar content, alongside an increase in lactic acid, acetic acid, and probiotic viability, up to 108 CFU/mL, post-fermentation. Notably, FGJ, particularly at 10 …


Effect Of Chromium Metal Alloy Fabrication Techniques On Enamel Wear, Pattrapond Eopsirisuk Jan 2023

Effect Of Chromium Metal Alloy Fabrication Techniques On Enamel Wear, Pattrapond Eopsirisuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

This in vitro study aimed to investigate the effect of different chromium metal alloys on enamel wear through longitudinal observation across various simulated chewing cycles. Four groups of alloys were studied (n=10 per group): casting Ni-Cr alloys (NC), casting Co-Cr alloys (CC), SLM Co-Cr alloys (CS), and heat-treated SLM Co-Cr alloys (CS-H). The test simulated chewing of enamel cusps against the alloys in distilled water under specific conditions (49 N load, 0.7 mm sliding movement, and 1.6 Hz frequency). Enamel wear was measured at 60,000, 120,000, and 240,000 cycles by using intraoral scanner matching with open-source 3D software. Enamel wear …


Comparison Of Removal Torques Among Different Abutments In Single Implant Crowns After Cyclic Loading: An In Vitro Study, Suppanut Jongsiri Jan 2023

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 …


Factors Influencing Mode Choice Selection And Intention Of Public Transport Users : A Comparative Study Between Thailand And Indonesia During Pandemic, Aditya Mahatidanar Hidayat Jan 2023

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 Jan 2023

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 Jan 2023

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 …


The Diagnostic Accuracy Of Maxillary Fungal Ball Rhinosinusitis In Paranasal Sinus Computed Tomography Using Deep Learning Models, Pakapoom Sukswai Jan 2023

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 …


Polycationic Colicin N Inhibits Metastatic Activity In Human Lung Cancer Cells Through Suppression On Epithelial To Mesenchymal Transition, Lwin Lwin Aye Jan 2023

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 …


Bamboo Biochar For Bar Adsorptive Microextraction Of Parabens In Water, Maytinee Jantorn Jan 2023

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 …


Crosslinking Enhancement Of Natural Rubber By Electron Beam, Mili Purbaya Jan 2023

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 Jan 2023

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 Jan 2023

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 …


Worksheet - Boom Sprayer 1 Minute Method, George Hamilton Jan 2023

Worksheet - Boom Sprayer 1 Minute Method, George Hamilton

UNH Cooperative Extension

No abstract provided.


Diy Handwashing Stations, Mary S. Choate Jan 2023

Diy Handwashing Stations, Mary S. Choate

Advisory Council

No abstract provided.