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An Investigation Of The Relationship Between Subjective Mental Workload And Objective Indicators Of User Activity, Greg Byrne Jan 2022

An Investigation Of The Relationship Between Subjective Mental Workload And Objective Indicators Of User Activity, Greg Byrne

Dissertations

Whilst the concept of physical workload is intuitively understood and readily applicable in system design, the same cannot be said of mental workload (MWL), despite its importance in our increasingly technological society. Despite its origin in the mid 20th century, the very concept of ”mental workload” is still a topic of debate in the literature, although it can be loosely defined as “the amount of mental work necessary for a person to complete a task” (Miller, 1956; Longo, 2014). Several methods have been utilized to measure of MWL, including physiological methods such as neuro-imagery, performance-based metrics, and subjective measures via …

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Kg-Cnn: Augmenting Convolutional Neural Networks With Knowledge Graphs For Multi-Class Image Classification, Aidan O'Neill Jan 2022

Kg-Cnn: Augmenting Convolutional Neural Networks With Knowledge Graphs For Multi-Class Image Classification, Aidan O'Neill

Dissertations

Computer vision is slowly becoming more and more prevalent in daily life. Tesla has recently announced that it plans to scale up the manufacturing of their Robotaxis by 2024, with this increase in self-driving vehicles being just one example, the importance of computer vision is growing year by year. Vision can be easy to take for granted, as most humans grow up using vision as their primary way of absorbing environmental information. The way humans process and classify visual information differs significantly from how current computer vision systems process and organise visual information. The human brain can use its past …

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Between Hopes And Threats: New Migratory Birds Records On The Sawala Mandapa Education And Training Forest, Indonesia, Dian Iswandaru, Gugie Nugraha, Aris Djati Dwi Iswanto, Yulia Rahma Fitriana, Kornelia Webliana Jan 2022

Between Hopes And Threats: New Migratory Birds Records On The Sawala Mandapa Education And Training Forest, Indonesia, Dian Iswandaru, Gugie Nugraha, Aris Djati Dwi Iswanto, Yulia Rahma Fitriana, Kornelia Webliana

Forest and Society

Java Island is one of the tropical areas for bird migration, especially the Asian-Australian flyway of migratory birds. The SMETF is one of the protected forest areas that migratory birds can visit in Java. This research aims to identify migratory birds in SMETF. Transect and point count methods are used to observe migratory bird movements and their activities. In the research area, four migratory birds were identified: Ficedula zanthopygia, Agropsar sturninus, Pernis ptilorhynchus o., and Accipiter soloensis. The first and second species showed many activities for four months from October 2020 to January 2021, and this …

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The Livelihood Adjustment Of Smallholding Rubber Farming Systems (Srfs) In Southwestern Thailand: Case Study In Ranong, Krabi, Phangnga, And Phuket Provinces, Chaiya Kongmanee, Buncha Somboonsuke, Milinpat Boonkongma, Prawat Wettayaprasit, Rawee Chiarawipa, Kamonwan Sae Chong, Kanata Thatthong, Panuphan Prapatigul Jan 2022

The Livelihood Adjustment Of Smallholding Rubber Farming Systems (Srfs) In Southwestern Thailand: Case Study In Ranong, Krabi, Phangnga, And Phuket Provinces, Chaiya Kongmanee, Buncha Somboonsuke, Milinpat Boonkongma, Prawat Wettayaprasit, Rawee Chiarawipa, Kamonwan Sae Chong, Kanata Thatthong, Panuphan Prapatigul

Forest and Society

This study aimed to examine the livelihood adjustment, to analyze factors affecting, and to synthesize the relationships between production and livelihood adjustment in model of SRFS for Ranong, Krabi, Phangnga, and Phuket provinces, in Southwestern Thailand. A sample group of 399 rubber farmers was involved in data collection and 60 key informants were selected as a subsample. A structured interview form and a semi-structured interview form were the tools for data collection. In data analysis, descriptive statistics, linear regression and technical- economic simulation were applied, as well as synthesized model of connections between the production system and livelihood under SRFS …

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Covid-19 And Forest Communities: Alignment And Challenges On Case Studies In Forest Community, Pemalang, Indonesia, Robert Siburian, Dicky Rachmawan, Fanny Henry Tondo Jan 2022

Covid-19 And Forest Communities: Alignment And Challenges On Case Studies In Forest Community, Pemalang, Indonesia, Robert Siburian, Dicky Rachmawan, Fanny Henry Tondo

Forest and Society

A pandemic, last seen a century ago, has reappeared in 2019 under the name of Covid-19. Poor forest communities are also especially affected by this pandemic. The qualitative method through literature and case study is used to explain the connection between the emergence of COVID-19, forest destruction, and its impact on the lives of people in forests in Indonesia. Two cases are going to be models of forest communities in Pemalang, namely LMDH Rawa Sakti and KTH GGL. The program was established by the Ministry of Environment and Forest (MoEF) to create a supportive atmosphere for forest communities’ survival to …

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Commoning The State Forest: Crafting Commons Through An Indonesian Social Forestry Program, Haudec Herrawan, Nurhady Sirimorok, Munajat Nursaputra, Emban Ibnurusyd Mas'ud, Fatwa Faturachmat, Andi Sadapotto, Supratman Supratman, Yusran Yusran, Muhammad Alif K. Sahide Jan 2022

Commoning The State Forest: Crafting Commons Through An Indonesian Social Forestry Program, Haudec Herrawan, Nurhady Sirimorok, Munajat Nursaputra, Emban Ibnurusyd Mas'ud, Fatwa Faturachmat, Andi Sadapotto, Supratman Supratman, Yusran Yusran, Muhammad Alif K. Sahide

Forest and Society

Studies of the commons grew out of responses to Hardin's bleak prediction of “tragedy of the commons,” that without state intervention or privatization, any commons will eventually be destroyed by allegedly self-interested users. As such, the commons studies traditionally tend to demonstrate cases where common pool resources (CPR) can be sustainably managed by groups of people beyond the state and market interventions. This paper shows a case from Sulawesi, Indonesia, where a state social forestry program can create a space for the program beneficiaries to build a commons. Through fieldwork that involves participant observation and in-depth interviews with program extension …

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Protumorigenic Effects Of Mixed Lineage Kinase Domain-Like Protein In Cholangiocarcinoma Cells, Nattaya Duangthim Jan 2022

Protumorigenic Effects Of Mixed Lineage Kinase Domain-Like Protein In Cholangiocarcinoma Cells, Nattaya Duangthim

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cholangiocarcinoma (CCA), a heterogeneous malignancy of bile duct system, has the highest incidence in Thailand. CCA is one of the leading causes of death which has low 5-year survival rate from 5% to 10% in advanced stages due to the difficulty of diagnosis in early stage and lack of effective therapies. Therefore, understanding the molecular mechanisms and pathogenesis of CCA development and progression is urgently needs and will lead to the development of novel therapeutic targets and strategies. Mixed lineage kinase domain-like (MLKL) was identified as a key effector in a novel regulated necrosis or necroptosis pathway. Recently studies have …

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The Combinatory Effects Of Pediatric Obesity And Ontogeny On Monocarboxylate Transporter Expression In Tissues Of Drug Disposition, Michael Ng Jan 2022

The Combinatory Effects Of Pediatric Obesity And Ontogeny On Monocarboxylate Transporter Expression In Tissues Of Drug Disposition, Michael Ng

University of the Pacific Theses and Dissertations

Proton-coupled and sodium-dependent monocarboxylate transporters are encoded by the SLC16A and SLC5A gene family of solute carriers, and are responsible for the transport of essential nutrients such as L-lactate, pyruvate, and ketone bodies. Basigin, or CD147, acts as an ancillary protein for MCT1 and MCT4, and is involved in membrane surface expression of transporters. MCT's are also involved in the shuttling of monocarboxylic xenobiotics across cell membranes, including the drugs valproate and gamma hydroxybutyrate. MCT’s are also important for normal mammalian development, particularly during embryogenesis and early neonatal life. Previous studies have shown that ketogenic diets increase MCT expression in …

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Land-Use And Ant Biodiversity In California’S Central Valley, Laura L. Navarro Jan 2022

Land-Use And Ant Biodiversity In California’S Central Valley, Laura L. Navarro

University of the Pacific Theses and Dissertations

The growing human population results in growing demand for land allocated to urban development and agricultural production (Godfray et al. 2010; Tilman et al. 2011; McDonnell and Hahs 2013; Alexander et al. 2015; Erlwein and Pauleit 2021). Changes to land allocation associated with agricultural and urban development will increasingly alter terrestrial ecosystems impacting biodiversity (Ricketts et al. 2001; McDonald et al. 2008). Ants are an ideal organism for monitoring changes in biodiversity related to land-use change due to their ubiquitous nature, high diversity, and their role as bioindicators. The goal of this study was to assess the diversity of the …

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Quality Parameters Of Wet And Dry Aged Beef Loins From Cattle Fed High Doses Of Vitamin E, David M. Velazco, Joe A. Sonderman, Nicolas J. Herrera, Chris Calkins Jan 2022

Quality Parameters Of Wet And Dry Aged Beef Loins From Cattle Fed High Doses Of Vitamin E, David M. Velazco, Joe A. Sonderman, Nicolas J. Herrera, Chris Calkins

Nebraska Beef Cattle Reports

The objective of this experiment was to determine if dietary supplementation of high doses of vitamin E (alpha-tocopherol; 2,200 IU per day for 100 days) can impact quality attributes of wet and dry-aged beef strip loins. Steaks from beef cattle supplemented with high doses of vitamin E exhibited less lipid oxidation after wet or dry aging, took longer time to discolor during retail display, and sustained redder color for a longer period under retail display conditions compared to controls. Free amino acids related to positive beef flavor attributes were higher for dry-aged loins compared to traditional wet aged samples loins. …

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Beef Quality And Oxidative Stability From Cattle Fed High Levels Of Vitamin E, Nicolas J. Herrera, Joe A. Sonderman, David M. Velazco, Chris Calkins Jan 2022

Beef Quality And Oxidative Stability From Cattle Fed High Levels Of Vitamin E, Nicolas J. Herrera, Joe A. Sonderman, David M. Velazco, Chris Calkins

Nebraska Beef Cattle Reports

Meat color is a major factor for consumer meat purchasing decisions. Aging beef, which can improve tenderness, has been shown to accelerate discoloration in fresh beef, shortening retail display time, and generating negative flavor attributes. The objective of this study was to evaluate supplementing cattle high levels (2,200 International Units/ day) of Vitamin E to sustain meat quality during prolonged retail display in beef strip loins after 2 or 14 days aging compared to commercially-produced loins selected as controls. Results showed a treatment x age effect for Warner-Bratzler shear force and free calcium content, primarily due to aging. A dietary …

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Effect Of Feeding Cars On Digestibility And Fatty Acid Flow In Finishing Cattle Diets, John C. Gibbons, Mitchell M. Norman, Tyler J. Spore, Hannah C. Wilson, Kylie Butterfield, Andea K. Watson, Galen E. Erickson, Jonathan W. Wilson Jan 2022

Effect Of Feeding Cars On Digestibility And Fatty Acid Flow In Finishing Cattle Diets, John C. Gibbons, Mitchell M. Norman, Tyler J. Spore, Hannah C. Wilson, Kylie Butterfield, Andea K. Watson, Galen E. Erickson, Jonathan W. Wilson

Nebraska Beef Cattle Reports

An experiment was conducted to evaluate the impact of a liquid feed, Condensed Algal Residue Solubles (CARS) on diet digestibility and fatty acid flow to the small intestine. Three treatments included CARS at 0, 2.5, and 5% of the diet dry matter, replacing steam-flaked corn. The base diet included 73, 70.5, or 68% steam flaked corn, 15% dried distillers grains plus solubles, 8% alfalfa haylage, and 4% supplement. Inclusion of CARS in the diet did not affect dry matter or organic matter intake or digestibility of dry matter, organic matter or neutral detergent fiber. Amount of fatty acid flowing to …

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Evaluation Of Green Grass On Nutrient Digestibility And Fatty Acid Flow In Cattle Finishing Diets, Aksel R. Wiseman, Tyler J. Spore, Mitchell M. Norman, Hannah C. Wilson, J. C. Macdonald, Andrea K. Watson, Galen E. Erickson Jan 2022

Evaluation Of Green Grass On Nutrient Digestibility And Fatty Acid Flow In Cattle Finishing Diets, Aksel R. Wiseman, Tyler J. Spore, Mitchell M. Norman, Hannah C. Wilson, J. C. Macdonald, Andrea K. Watson, Galen E. Erickson

Nebraska Beef Cattle Reports

Six ruminally and duodenally cannulated steers were utilized in a 3 × 3 replicated Latin square experiment to test 0, 15, and 30% dietary inclusion of Green Grass (Sunseo Omega 3; Chungcheong Duk-Do, South Korea), a feed comprised of sesame meal, giant kelp, cassava, and sorghum (not currently approved to be fed in the US). Dry matter and fiber intake increased linearly with increased Green Grass inclusion. Dry matter and organic matter digestibility were not affected by Green Grass inclusion. Concentration of saturated fatty acids at the duodenum were similar for Green Grass 0 and Green Grass 15 with a …

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Effect Of Biochar As A Feedlot Pen Surface Amendment On Manure Nutrient Capture, J. L. Sperber, Braden C. Troyer, Mitchell M. Norman, Levi J. Mcphillips, Heather Nobert, Andrea K. Watson, Galen E. Erickson Jan 2022

Effect Of Biochar As A Feedlot Pen Surface Amendment On Manure Nutrient Capture, J. L. Sperber, Braden C. Troyer, Mitchell M. Norman, Levi J. Mcphillips, Heather Nobert, Andrea K. Watson, Galen E. Erickson

Nebraska Beef Cattle Reports

Two mass balance experiments were conducted during winter and summer seasons to evaluate the effect of spreading biochar on the feedlot pen surface on manure nutrient retention. The winter experiment (Dec to June) evaluated three treatments including biochar spread to pen surface (approximately 54 lb of biochar per steer), hydrated lime spread to pen surface (cooperation with UNL Environmental Engineering; approximately 68 lb per steer) and negative control (no treatment applied). The summer experiment (June to Nov) evaluated biochar treatment (approximately 68 lb of biochar per steer) against negative control. Biochar utilized in winter and summer was unprocessed and sourced …

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Interaction Of Sweet Bran Inclusion And Corn Processing Method In Beef Finishing Diets, Rebecca L. Sjostrand, Levi J. Mcphillips, Braden C. Troyer, Maggie Youngers, Rick Stock, J. C. Macdonald, Galen E. Erickson Jan 2022

Interaction Of Sweet Bran Inclusion And Corn Processing Method In Beef Finishing Diets, Rebecca L. Sjostrand, Levi J. Mcphillips, Braden C. Troyer, Maggie Youngers, Rick Stock, J. C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

The effects of corn processing method and Sweet Bran concentration on finishing cattle performance and carcass characteristics were evaluated in steam-flaked corn or a blend of high-moisture and dry-rolled corn-based diets. Sweet Bran was included at 0, 20, or 40% of diet dry matter. When cattle were fed 0% Sweet Bran, feeding steam-flaked corn resulted in a 11.7% improvement in feed conversion and heavier hot-carcass weight compared to feeding high-moisture/ dry-rolled corn. As Sweet Bran increased in the diet, there was a linear improvement in feed conversion for high-moisture/dry-rolled corn-fed steers and no change in feed conversion for steam-flaked corn-fed …

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Effect Of Rapeseed Inclusion In Late-Summer Planted Oat Pasture On Growing Performance Of Beef Steers, Devin A. Jakub, Hannah E. Riley, Kristin E. Hales, Steven D. Shackelford, Harvey C. Freetly, M. E. Drewnoski Jan 2022

Effect Of Rapeseed Inclusion In Late-Summer Planted Oat Pasture On Growing Performance Of Beef Steers, Devin A. Jakub, Hannah E. Riley, Kristin E. Hales, Steven D. Shackelford, Harvey C. Freetly, M. E. Drewnoski

Nebraska Beef Cattle Reports

An oat monoculture was planted in late summer at 100 lb/ac and compared to oats planted at 50 lb/ac with rapeseed included at 3 lb/ac. Seed cost of the oat monoculture ($20/ac) was greater than the mix ($15/ac). Initial forage yield was not affected by the inclusion of rapeseed with fall oat. Calf gain was significantly greater and cost of gain was significantly decreased when rapeseed was included due to the combination of greater gains and lesser seed cost. Including rapeseed in late summer planted oats may be beneficial for producers who want to graze growing calves in the fall.

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Interaction Of Urea With Frequency And Amount Of Distillers Grains Supplementation On Growing Steer Rumen Digestion Parameters, Haley F. Linder, Joshua E. Sebade, Tyler J. Spore, M. E. Drewnoski, J. C. Macdonald Jan 2022

Interaction Of Urea With Frequency And Amount Of Distillers Grains Supplementation On Growing Steer Rumen Digestion Parameters, Haley F. Linder, Joshua E. Sebade, Tyler J. Spore, M. E. Drewnoski, J. C. Macdonald

Nebraska Beef Cattle Reports

Ruminally cannulated steers were used in 8 × 6 row-column design with 8 animals and 6 periods. Treatment design was a 2 × 2 × 2 factorial, with factors including amount of supplementation, frequency of supplementation, and inclusion of urea. Hay dry matter intake was reduced by increased amount of supplementation and by decreased frequency of supplementation. Total VFA concentration did not differ among treatments. Rumen ammonia-N concentration was impacted by an interaction of amount of supplementation and inclusion of urea but there was no effect of supplementation frequency. In situ NDF disappearance did not differ between daily and alternate …

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Comparison Of Partially Confined And Traditional Cow-Calf Systems, Zac E. Carlson, Levi J. Mcphillips, Galen E. Erickson, M. E. Drewnoski, J. C. Macdonald Jan 2022

Comparison Of Partially Confined And Traditional Cow-Calf Systems, Zac E. Carlson, Levi J. Mcphillips, Galen E. Erickson, M. E. Drewnoski, J. C. Macdonald

Nebraska Beef Cattle Reports

Production of cow-calf pairs and grow/finish performance of calves from a partially-confined, fall-calving, intensive cow-calf system were compared to a traditional, spring-calving, extensive cow-calf system. Body condition was lower at breeding and weaning for the fall-calving alternative system compared to the traditional, spring-calving system. Conception, calving, and weaning rates were not different among treatments. Weaning weights were lower for the fall-calving alternative system than traditional, spring-calving system. Following weaning, calves were grown for 117 d and then subsequently finished to the same target fatness for both systems. In the grower phase, gain was greater and feed conversion improved for the …

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Food Inflation During The Covid-19 Pandemic. A Comparison Between Brazilian And Thai Food Inflation During The Years 2020 And 2021., Lilian Cordeiro Prates Jan 2022

Food Inflation During The Covid-19 Pandemic. A Comparison Between Brazilian And Thai Food Inflation During The Years 2020 And 2021., Lilian Cordeiro Prates

Chulalongkorn University Theses and Dissertations (Chula ETD)

Thailand and Brazil are two prominent net agro-exporters, and both countries were hit severely by the Pandemic of Covid-19. While Thailand's GDP decreased by 6.1% in 2020, the Brazilian economy shrank by 4.1%. Despite these similarities, during the acute phase of the pandemic, food prices in Brazil started to increase at an accelerated pace while, in Thailand, food prices remained low and stable. In 2020, the annual food inflation in Brazil was 14,11%, and Thailand's was 1.37%. Therefore, this study aims to contribute to the literature by filling the information gap about food inflation dynamics in those two countries during …

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Hydrolysis Of Grass Xylan By Xylanases From Aureobasidium Pullulans For Xylooligosaccharide And Xylitol Productions, Sorawit Na Nongkhai Jan 2022

Hydrolysis Of Grass Xylan By Xylanases From Aureobasidium Pullulans For Xylooligosaccharide And Xylitol Productions, Sorawit Na Nongkhai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Ten grass samples were screened for potential as a xylan source and five including sugarcane leaf, purple guinea grass, Napier grass, sabi grass and vetiver grass were selected for optimization of xylan extraction. After optimization, sugarcane leaf gave the highest xylan recovery at 99.42% when it was extracted by 14.32% (w/v) NaOH at 13.25:1 liquid: solid ratio with 32.36-min steaming time. From the xylan structural and sugar composition analyses, the major xylan from sugarcane leaf was arabinoxylan whereas those from the other grass samples were (glucurono)arabinoxylan. Xylans from sugarcane leaf, purple guinea grass and Napier grass were selected for further …

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Foam-Mat-Freeze Dried Clove Essential Oil Nanoemulsion For Inhibition Of Spoilage Microorganisms In Whiteleg Shrimp Litopenaeus Vannamei, Puncharat Pilong Jan 2022

Foam-Mat-Freeze Dried Clove Essential Oil Nanoemulsion For Inhibition Of Spoilage Microorganisms In Whiteleg Shrimp Litopenaeus Vannamei, Puncharat Pilong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research developed foam-mat freeze-dried clove essential oil nanoemulsion (FFD-CN) for inhibiting food spoilage microorganisms. This research comprised three parts. Firstly, the fabrication of clove essential oil nanoemulsion (CN) was optimized. The characteristics including particle size, polydispersity index (PDI), Zeta-potential, and viscosity of the fabricated nanoemulsions were observed. The optimal CN having a droplet size of 30.76 nm, PDI of 0.179, Zeta-potential of -50.01 mV, and viscosity of 7.81 cP was achieved at 1% v/v clove oil and 3% v/v Tween® 80 concentration and 10,000 psi operating pressure. The CN exhibited stability against particle aggregation and phase separation throughout storage. …

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Simulation Of Photoelectrochemical Co2 Conversion To Useful Chemicals, Aroonroj Chaosukho Jan 2022

Simulation Of Photoelectrochemical Co2 Conversion To Useful Chemicals, Aroonroj Chaosukho

Chulalongkorn University Theses and Dissertations (Chula ETD)

Photoelectrochemical (PEC) CO2 reduction reaction (CO2 RR) is one of the possible solutions to reduce CO2 emissions. Among a variety of products derived from CO2 RR, CO, and HCOO- are found to be interesting chemicals. The geometry and arrangement of the main components of PEC cells play important roles in the cell performance of CO2 RR. In this study, a correlation of hydrodynamics and kinetics on the TiO2-photoanode and SnO2-GDE, used as a cathode, was investigated by COMSOL Multiphysics by controlling operating conditions for 2-dimensional different PEC cell configurations. The Microfluidic flow cell (MFC) with a zero-gap anode with a …

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Techno-Economic Analysis Of Succinic Acid Production From Sugarcane Molasses, Apitsada Rongsawad Jan 2022

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 …

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Techno-Economic And Environmental Assessment For Enhancementbiodiesel Production Process Using Rotating Tube Reactor And Dry Washing, Arthit Jarungwongsathien Jan 2022

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 …

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Enzymatic Pretreatment Of Rice Bran Acid Oil Before Γ-Oryzanol Recovery, Asdarina Binti Yahya Jan 2022

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, …

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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 Jan 2022

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, …

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Simultaneous Reaction And Separation Technologies For Biodiesel Production Derived From Alternative Feedstocks, Nattawat Petchsoongsakul Jan 2022

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 …

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Sulfur-Tolerant Cobalt-Doped La0.3sr0.7tio3-D-Perovskite Cathode For Intermediate-Temperature Solid Oxide Electrolysis Cell, Natthamon Nuengjumnong Jan 2022

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 …

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Improvement Of Hydrodynamics And Heat Transfer In Biomass Fluidized Bed Combustor With Immersed Tubes Using Cfd-Dem, Krittin Korkerd Jan 2022

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 …

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Chemical Constituents From The Fresh Pericarps Of Mature Mangosteen Fruit Garcinia Mangostana, Ahmad Tijani Azeez Jan 2022

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) …

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