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Articles 36691 - 36720 of 37743
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Production Of 1, 12- Dodecanedioic Acid By Recombinant Microbial Cytochrome P450 In Pichia Pastoris And Saccharomyces Cerevisiae, Phawadee Buathong
Production Of 1, 12- Dodecanedioic Acid By Recombinant Microbial Cytochrome P450 In Pichia Pastoris And Saccharomyces Cerevisiae, Phawadee Buathong
Chulalongkorn University Theses and Dissertations (Chula ETD)
1,12-Dodecanedioic acid (DDA) is a primary compound which is used as an intermediate precursor for production of valuable chemical products. Biosynthesis of 1,12-DDA by recombinant (r) microorganisms can be used as an alternative method to compensate several disadvantages from chemical synthesis. The purpose of this study was to clone a CYP52A17 from Candida tropicalis to produce cytochrome P450 which can terminally oxidize fatty acids to hydroxy-fatty acids and further to dicarboxylic acids (ω-oxidation). The wild type rCYP52A17 and its engineered L261S/L490S (leucine changed to encode for serine) form (rCYP52A17mut) were expressed in Pichia pastoris and Saccharomyces cerevisiae which coexpressing the …
Optimization Of Protein Hydrolysate Preparation And Their Angiotensin I-Converting Enzyme Inhibitory Activity From Shiitake Mushrooms Lentinula Sp., Supawee Paisansak
Optimization Of Protein Hydrolysate Preparation And Their Angiotensin I-Converting Enzyme Inhibitory Activity From Shiitake Mushrooms Lentinula Sp., Supawee Paisansak
Chulalongkorn University Theses and Dissertations (Chula ETD)
Angiotensin-I converting enzyme (ACE) is a key enzyme involved in regulating blood pressure. ACE converts angiotensin-I into angiotensin-II, which results in raised blood pressure. Inhibition of ACE leads to a decreased concentration of angiotensin-II and lowering of blood pressure. Food protein-derived ACE inhibitory peptides are considered to be a safer alternative to antihypertensive drugs. Shiitake mushrooms, one of the most consumed mushrooms in Thailand, are recognized as a nutritive food with health-stimulating properties. The aim of this study was to optimize the preparation of a shiitake-protein hydrolysate and investigate the ACE inhibitory activity of the hydrosylate. Shiitake mushrooms were hydrolyzed …
Simulation Of Water Effect On Biodiesel Production Using Waste Cooking Oil Via Ester-Transesterification In A Reactive Distillation Column, Ajala Anantapinitwatna
Simulation Of Water Effect On Biodiesel Production Using Waste Cooking Oil Via Ester-Transesterification In A Reactive Distillation Column, Ajala Anantapinitwatna
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the effect of water content in waste cooking oil (WCO) on the performance of a reactive distillation column for biodiesel production via ester-transesterification. A mixture of triolein and oleic acid was used as a WCO model compound. Amberlyst-15 was used to catalyze esterification while CaO was used for transesterification. From Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model taking into account water absorption for esterification of oleic acid (FFA), biodiesel yield was decreased with increasing of water content in WCO feedstocks. On the other hand, the initial rate of transesterification was increased with increase of amount of water in WCO feedstocks …
Synthesis Of Activated Carbons From Coffee Ground Residues And Their Application As Catalysts For Ethanol Dehydrogenation, Jeerati Ob-Eye
Synthesis Of Activated Carbons From Coffee Ground Residues And Their Application As Catalysts For Ethanol Dehydrogenation, Jeerati Ob-Eye
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this present study, characteristics and catalytic properties of activated carbon derived from coffee ground residue, cobalt metal (Co) supported-activated carbon and various metals (Ce, Co, Cu and Ni) supported-commercial activated carbon were determined and characterized. This study was divided into three parts. Regarding to the first part, the synthesis of activated carbon catalysts derived from coffee ground residues with different methods of physical activation was investigated. The results showed that the catalyst with physically activated by CO2 for 4 hours, exhibited the best catalytic activity of ethanol dehydrogenation to acetaldehyde. In the second part, the best catalyst from the …
Simulation And Evaluation Of Butadiene Production From Ethanol Via One-Step Reaction, Jirawat Imsaard
Simulation And Evaluation Of Butadiene Production From Ethanol Via One-Step Reaction, Jirawat Imsaard
Chulalongkorn University Theses and Dissertations (Chula ETD)
1,3-butadiene is an important compound produced from the steam cracking process. Raising demand for alternatives to fossil fuels has led to an increase in bio-derived ethanol production, which can also be used as a feedstock for 1,3-butadiene synthesis. This research investigated the simulation of 1,3-butadiene production from ethanol using one-step process with 1.AI2O3/ZnO (60:40), 2.MgO-SiO2-Na2O (1:1)(0.1%) and 3.Hf2.5ZM1.6/SiO2 as heterogeneous catalysts. The process simulation was carried out using commercial Aspen plus 8.0 program and the heat utilization efficiency was evaluated by Aspen energy analyzer software. The process optimal condition sequences were identified by adjusting the separation distillation parameters which include …
Effects Of Tio2 Support And Co Addition On Ni/Tio2 Catalysts In Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Kittithad Wonglekha
Effects Of Tio2 Support And Co Addition On Ni/Tio2 Catalysts In Selective Hydrogenation Of Furfural To Furfuryl Alcohol, Kittithad Wonglekha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Furfuryl alcohol is an important chemical intermediate that can be converted into many value-added derivative molecules. It is typically produced by the hydrogenation of furfural using supported metal catalysts. In this work, 15%wt Ni catalysts supported on titania (TiO2) were prepared by incipient wetness impregnation method. The effects of phase composition and average crystallite sizes of TiO2 and Co addition in the range of 1-3 wt% on the catalytic properties of 15 wt%Ni/TiO2 were investigated in the selective hydrogenation of furfural to furfuryl alcohol at 50°C, 20 bar of H2, and 2 h reaction time. It was found that Ni …
Hydrothermal Carbonization Carbon-Based Acid Catalyst For Biodiesel Production, Laddawan Tumkot
Hydrothermal Carbonization Carbon-Based Acid Catalyst For Biodiesel Production, Laddawan Tumkot
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aims to synthesize the production of biodiesel (oleic acid methyl ester) by esterification in the presence of sulfonated hydrothermal carbon based catalyst under microwave irradiation. The catalyst was prepared by hydrothermal carbonization, followed by sulfonation presenting sulfonic acid group as an active site. The catalyst characterization results confirmed good microwave-absorptivity of the catalyst which can be heated directly and accelerate the reaction immediately at the surface of the catalyst. Esterification of oleic acid (OA) with methanol experiments were optimized by using response surface methodology based on central composite design. Three variables: molar ratio of methanol to OA (2.5:1-7.5:1), …
Graphene Sheets Decorated With Silver Nanoparticles As An Oxygen Reduction Reaction Catalyst For Zinc-Air Battery, Laksanaporn Poolnapol
Graphene Sheets Decorated With Silver Nanoparticles As An Oxygen Reduction Reaction Catalyst For Zinc-Air Battery, Laksanaporn Poolnapol
Chulalongkorn University Theses and Dissertations (Chula ETD)
The aim of this thesis is to develop a catalyst for the cathode of a zinc-air battery and to investigate the effects of reduced graphene oxide decorated with silver nanoparticles on the cathode in the zinc-air battery. First, reduced graphene oxide (AgNPs/rGO) was synthesized using glucose reduction at 60 degrees Celsius. Next, the structure and morphology of AgNPs/rGO were checked using X-ray diffraction (XRD). Then, transmission electron microscopy (TEM) analyzes were carried out. The amount of silver (Ag) decorate in graphene oxide was confirmed by EDX. Next, the synthesized catalysts at 3 concentration, using a rotating disk electrode (RDE), led …
การใช้เชื้อเพลิงดีเซลสังเคราะห์จากขยะพลาสติกในเครื่องยนต์ Ci ชนิด Direct Injection, ยุทธนา ชาญณรงค์ชัย
การใช้เชื้อเพลิงดีเซลสังเคราะห์จากขยะพลาสติกในเครื่องยนต์ Ci ชนิด Direct Injection, ยุทธนา ชาญณรงค์ชัย
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้จัดทำขึ้นเพื่อศึกษาผลของการใช้เชื้อเพลิงดีเซลสังเคราะห์จากขยะพลาสติกที่มีต่อสมรรถนะ ปรากฏการณ์การเผาไหม้รวมถึงค่าควันดำของเครื่องยนต์ ซึ่งในงานวิจัยนี้จะทดสอบกับเครื่องยนต์ Kubota รุ่น RT 140 DI โดยสามารถแบ่งการทดสอบออกได้เป็น 3 ส่วน โดยส่วนที่หนึ่งเป็นการทดสอบเพื่อดูค่าสมรรถนะที่สภาวะคงตัว ความเร็วรอบคงที่ ตั้งแต่ 1000 - 2400 รอบ/นาที ทั้งที่สภาวะภาระสูงสุดและภาระบางส่วนของเครื่องยนต์ พบว่า ที่ภาระสูงสุดของเครื่องยนต์เมื่อใช้เชื้อเพลิงดีเซลสังเคราะห์จากขยะพลาสติกสามารถสร้างค่าแรงบิดเบรกและกำลังเบรกได้น้อยกว่าเชื้อเพลิงดีเซลเนื่องจากมีอัตราการสิ้นเปลืองเชื้อเพลิงน้อยกว่าซึ่งเป็นผลมาจากความหนาแน่นของเชื้อเพลิงที่น้อยกว่า แม้จะมีค่าความร้อนของเชื้อเพลิงที่สูงกว่าจึงมีค่าอัตราการสิ้นเปลืองเชื้อเพลิงจำเพาะเบรกและค่าประสิทธิภาพการเปลี่ยนพลังงานเชื้อเพลิงเบรกดีกว่า และที่สภาวะภาระบางส่วนของเครื่องยนต์เมื่อใช้เชื้อเพลิงดีเซลสังเคราะห์จากขยะพลาสติกจะมีอัตราการสิ้นเปลืองเชื้อเพลิงจำเพาะเบรก ค่าประสิทธิภาพการเปลี่ยนพลังงานเชื้อเพลิงเบรกดีกว่าการใช้เชื้อเพลิงดีเซลสอดคล้องกับผลที่ภาระสูงสุด ส่วนที่สองเป็นการทดสอบค่าสมรรถนะของเครื่องยนต์และค่าควันดำที่จุดทดสอบตามมาตรฐาน ESC test cycle พบว่า เครื่องยนต์เมื่อใช้เชื้อเพลิงดีเซลสังเคราะห์จากขยะพลาสติกมีค่าสมรรถนะที่ดีกว่า ส่วนควันดำมีค่าเคียงกับเชื้อเพลิงดีเซล ส่วนที่สามเป็นผลการวิเคราะห์การเผาไหม้ของเครื่องยนต์เมื่อใช้เชื้อเพลิงดีเซลสังเคราะห์จากขยะพลาสติก ในการทดสอบจะทำการวัดความดันในห้องเผาไหม้ ความดันเชื้อเพลิงที่ทางเข้าหัวฉีดและองศาเพลาข้อเหวี่ยง โดยบันทึกข้อมูลทุก ๆ 2 องศาเพลาข้อเหวี่ยง จำนวน 200 วัฏจักรต่อจุดทดสอบ ที่จุดทดสอบตามมาตรฐาน ESC test cycle พบว่า จุดเริ่มต้นการฉีดเชื้อเพลิงจะเข้าใกล้ศูนย์ตายบนเมื่อความเร็วรอบมากขึ้น ความดันในห้องเผาไหม้สูงสุดมีค่าเพิ่มขึ้นเมื่อภาระการทดสอบมากขึ้น ส่วนอัตราการปลดปล่อยความร้อนสูงสุดและการปล่อยความร้อนสุทธิมีค่าเพิ่มขึ้นเมื่อภาระการทดสอบมากขึ้น โดยมีค่าสัดส่วนมวลเชื้อเพลิงที่เผาไหม้อยู่ในช่วง 0.732 - 0.866 ซึ่งไม่ต่างจากเชื้อเพลิงดีเซล จากผลการทดสอบสามารถสรุปได้ว่าเชื้อเพลิงดีเซลสังเคราะห์จากขยะพลาสติกสามารถนำไปให้ในเครื่องยนต์ CI ชนิด Direct Injection ได้โดยไม่ต้องมีการปรับแต่งเครื่องยนต์ โดยมีค่าประสิทธิภาพต่าง ๆ ที่ดีกว่าและค่าควันดำใกล้เคียงกับการใช้เชื้อเพลิงดีเซล
การจับยึดคาร์บอนไดออกไซด์บนถ่านกัมมันต์ดัดแปรด้วยเอมีนจากไม้ไผ่, ภานุพงศ์ ประเสริฐสุข
การจับยึดคาร์บอนไดออกไซด์บนถ่านกัมมันต์ดัดแปรด้วยเอมีนจากไม้ไผ่, ภานุพงศ์ ประเสริฐสุข
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้ทำการศึกษาการดูดซับคาร์บอนไดออกไซด์บนตัวดูดซับถ่านกัมมันต์ที่ได้จากไม้ไผ่ และตัวดูดซับถ่านกัมมันต์ที่ถูกกระตุ้นและดัดแปรด้วยเตตระเอทิลีนเพนทามีนหรือพอลิเอทิลีนอิมไมด์ ตัวแปรที่ศึกษามีดังนี้ อุณหภูมิที่ใช้ในการกระตุ้นด้วยคาร์บอนไดออกไซด์ อัตราส่วนน้ำหนักตัวดูดซับต่อน้ำหนักกรดฟอสฟอริก ชนิดของเอมีน ปริมาณเอมีนที่ใช้ และความชื้นในก๊าซขาเข้า ช่วงอุณหภูมิในการดูดซับตั้งแต่ 30 ถึง 110 องศาเซสเซียส ตัวดูดซับจะถูกวิเคราะห์ลักษณะพื้นที่ผิวจำเพาะด้วยเทคนิคดูดซับ/คายซับไนโตรเจนพบว่าการกระตุ้นด้วยคาร์บอนไดออกไซด์ที่อุณหภูมิ 600 ถึง 800 องศาเซสเซียสจะทำให้ตัวดูดซับมีพื้นที่ผิวจำเพาะและปริมาตรรูพรุนมีค่าสูงขึ้นโดยจะมีค่าเท่ากับ 432.92 ตารางเมตรต่อกรัม 0.23 ลูกบาศก์เซนติเมตรต่อกรัม ตามลำดับ เมื่อใช้อัตราส่วนน้ำหนักตัวดูดซับต่อน้ำหนักกรดฟอสฟอริกสูงขึ้นจะทำให้มีปริมาตรูพรุนขนาดเมโสและมาโครมากขึ้น จากการวิเคราะห์ด้วยเทคนิควิเคราะห์องค์ประกอบขั้นสูงพบว่าเมื่อเพิ่มน้ำหนักกรดฟอสฟอริก ทำให้มีปริมาณธาตุออกซิเจนสูง เมื่อวิเคราะห์หมู่ฟังก์ชันด้วยเทคนิคฟูเรียร์ทรานฟอร์มอินฟราเรดสเปกโทรสโคปี พบว่าเมื่อกระตุ้นด้วยคาร์บอนไดออกไซด์ที่อุณหภูมิสูงทำให้ตัวดูดซับเกิดการสลายตัว ส่วนการกระตุ้นด้วยกรดฟอสฟอริกจะพบหมู่ฟอสเฟสหลงเหลือที่พื้นผิวตัวดูดซับ จากการวิเคราะห์ความเป็นผลึกด้วยการเลี้ยวเบนของรังสีเอ๊กซ์ การกระตุ้นด้วยกรดฟอสฟอริกที่สัดส่วนสูงทำให้ระนาบ (001) (110) และ (002) เกิดจุดบกพร่อง จากผลการทดลอง พบว่าตัวดูดซับที่ถูกกระตุ้นด้วยคาร์บอนไดออกไซด์ที่อุณหภูมิ 700 องศาเซสเซียสจะให้ความสามารถในการดูดซับคาร์บอนไดออกไซด์เท่ากับ 0.97 มิลลิโมลต่อกรัม เมื่อนำมากระตุ้นด้วยกรดฟอสฟอริกแล้วดัดแปรด้วยเตตระเอทิลีนเพนทามีนพบว่า ความสามารถในการดูดซับคาร์บอนไดออกไซด์สูงขึ้นเป็น 1.14 มิลลิโมลต่อกรัม เมื่อไม่มีความชื้นในกระแสก๊าซขาเข้าและมีค่าเป็น 1.31 มิลลิโมลต่อกรัม เมื่อมีความชื้นในกระแสก๊าซขาเข้า ในส่วนของการศึกษาการฟื้นฟูสภาพตัวดูดซับพบว่า ความสามารถในการดูดซับลดลงประมาณร้อยละ 1.82 ในรอบที่ 10 ของวัฏจักรการดูดซับ ในส่วนของการศึกษาจลหพลศาสตร์พบว่าแบบจำลองปฏิกิริยาอันดับหนึ่งเทียมสามารถอธิบายกลไลการเกิดการดูดซับได้เหมาะสมที่สุด จากสมการของอาร์เรเนียสพบว่าเมื่อดัดแปรด้วยเอมีนทำให้มีค่าพลังงานกระตุ้นลดลงเนื่องจากหมู่เอมีนมีความว่องไวต่อคาร์บอนไดออกไซด์
Production And Characterization Of Cutinase From Tropical Fungi And Application With Detergent For Stain And Fuzz Removal From Spun Polyester Fabrics, Taweeporn Sooksai
Production And Characterization Of Cutinase From Tropical Fungi And Application With Detergent For Stain And Fuzz Removal From Spun Polyester Fabrics, Taweeporn Sooksai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Fungi were isolated from agricultural soil and plant specimens. Twenty three isolates from 44 fungal isolates were found to produce cutinase by using PCL-plate clearing assay and their cutinase activity were investigated. All the cutinase-producing fungi were cultured in liquid mineral medium (LMM) containing PCL or crude cutin extracted from papaya peels, which was a carbon source for cutinase production. Cutinase activity was assayed base on the hydrolysis of paranitrophenyl butarate (p-NPB). It was found that PBURU-T5 gave the highest cutinase activity. The isolate PBURU-T5 was selected for identification based on morphology together with comparative nucleotide sequencing from internal transcribed …
Reactive Extraction Of Metal Ion And Simultaneous Stripping Using Nanofibers-Supported Liquid Membrane In A Microchannel, Nattakarn Chucherd
Reactive Extraction Of Metal Ion And Simultaneous Stripping Using Nanofibers-Supported Liquid Membrane In A Microchannel, Nattakarn Chucherd
Chulalongkorn University Theses and Dissertations (Chula ETD)
Heavy metals in wastewater resulting from industries have become a prime concern for both environmental and economic reasons. This work intends to recover ions of heavy metal from wastewater using reactive extraction by nanofibers-supported liquid membrane (NSLM) in a microchannel. The use of supported liquid membrane enables simultaneous extraction and stripping (i.e., recovery of the extractant) processes. In this study, the NSLM was applied in a microchannel to minimize mass transfer resistance, hence improving overall performance of the extraction. Copper (II) ion was used as a model ion, while di-2-ethylhexyl phosphoric acid (D2EHPA) dissolved in kerosene was used as the …
Effect Of Metal Oxides On Zirconia For Ketonic Decarboxylation Of Methyl Stearate, Pawaphat Sartsri
Effect Of Metal Oxides On Zirconia For Ketonic Decarboxylation Of Methyl Stearate, Pawaphat Sartsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, the effect of characteristics of zirconia and metal oxide modified zirconia catalysts on the catalytic performance were investigated by ketonic decarboxylation of methyl stearate to desired ketone product at the optimal condition (400°C and 1 bar). Zirconia and metal oxide modified zirconia catalysts were characterized by using X-ray diffraction (XRD), Scanning electron microscope (SEM), N2-physissorption, X-ray photoelectron spectroscopy (XPS), and IR spectra of pyridine adsorption (Pyridine-IR). The results indicated that the transition metal oxide group modified zirconia catalysts have higher contents of total Lewis acid site and oxygen vacancies site, and lower content of total Brønsted acid …
Improving The Efficiency Of Dye-Sensitized Solar Cells With Ultrasonic Spray-Coated Tio2 Electrode That Was Modified By Mno2, Coo, Or Sno2, Supasun Thanadvanichkul
Improving The Efficiency Of Dye-Sensitized Solar Cells With Ultrasonic Spray-Coated Tio2 Electrode That Was Modified By Mno2, Coo, Or Sno2, Supasun Thanadvanichkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the modification of TiO2 electrode by adding the second metal oxide, namely, manganese dioxide (MnO2), cobalt oxide (CoO), or tin dioxide (SnO2) use in for dye-sensitized solar cell (DSSCs). TiO2 and modified TiO2 sols were synthesized via sol-gel methods. The sols were sprayed 500 times onto the fluorine-doped tin oxide glass substrates as a thin film using an ultrasonic spray coater. Finally, the thin film electrode was calcined at 400ºC for two hours. The amount of MnO2, CoO, or SnO2 was varied at 0, 0.1, 0.5, 1.0, and 3.0%wt. The photovoltaic efficiency of DSSCs was measured using …
Parametric Study Of Copper Zinc Tin Sulfide Thin Films By Convective Deposition Method, Thanawat Anantamongkolchai
Parametric Study Of Copper Zinc Tin Sulfide Thin Films By Convective Deposition Method, Thanawat Anantamongkolchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, most of the energy production is from fossil fuel-resources, which is a major source of greenhouse gases. Therefore, several researchers have been looking for the alternative energy that is clean and renewable energy. One of the outstanding alternatives is to utilize solar energy for conversion into electricity. Recently, CZTS (copper zinc tin sulfide, Cu2ZnSnS4) thin film solar cells have received numerous interest because of its decent energy band gap of about 1.4 - 1.6 eV, which matches with the solar spectrum, and its high absorption coefficient. Nevertheless, the manufacture of CZTS solar cells has used sophisticated methods for fabrication …
Tio2 Nanoparticles Coated Forward Osmosis Membranes For Treatment Of Industrial Textile Effluent, Kaung Ko Ko Sint
Tio2 Nanoparticles Coated Forward Osmosis Membranes For Treatment Of Industrial Textile Effluent, Kaung Ko Ko Sint
Chulalongkorn University Theses and Dissertations (Chula ETD)
Textile wastewater occur as demanding water bodies to be treated by membrane separation due to the complex composition and presence of reactive constituents such as heavy metals and salts as well as nutrients, e.g. nitrogen, sulphate and phosphate. Numerous combination of osmosis process with photocatalysts has been experimentally conceived for the water and wastewater treatment and reuse of textile wastewater. The present work was devoted to study the operating feasibility using photocatalyst as TiO2 nano-particles were coated onto two commercially available FO membranes, a cellulose triacetate (CTA) membrane and an aquaporin (AqP) membrane through a specially designed 3-(trimethoxysilyl) propyl methacrylate–polymethyl …
Women Political Participation In MyanmarS House Of Representatives, Thu Thu Swe
Women Political Participation In MyanmarS House Of Representatives, Thu Thu Swe
Chulalongkorn University Theses and Dissertations (Chula ETD)
The thesis mainly discusses about main obstacles and challenges for women to participate in political activities in Myanmar including economic factor, social factor, political factor, and the ways how women are empowered to participate in political activities in Myanmar by using both primary and secondary data. The primary concept for this study is based on women empowerment processes which are included four different pathways in which women are changed –material (economy), perceptual (knowledge and skill), cognitive (self-confident and self-esteemed) and relational (bargaining power). Moreover, the thesis analyses actor's roles in these four pathways. The thesis found out external factors namely …
Methane And Carbon Dioxide Adsorption On Al-Based And Zr-Based Mofs: Effects Of Amino-Functionalization, Orawee Lamoonkit
Methane And Carbon Dioxide Adsorption On Al-Based And Zr-Based Mofs: Effects Of Amino-Functionalization, Orawee Lamoonkit
Chulalongkorn University Theses and Dissertations (Chula ETD)
For natural gas storage, adsorbed natural gas (ANG) technology has attracted great attention. There is a wide range of porous materials for ANG, but the most promising porous adsorbents for natural gas are metal organic frameworks (MOFs). This study examined adsorption of carbon dioxide and methane gases on aluminium (Al) based MOFs and zirconium (Zr) based MOFs including MIL-53(Al), MIL-53(Al)-NH₂, UiO-66, UiO-66-NH₂ 25%, UiO-66-NH₂ 50%, UiO-66-NH₂ 75%, and UiO-66-NH₂. Experiments were carried out in a static system at 33°C and pressures up to 100 psi. Characterization and structural analysis of the adsorbents were investigated by Fourier transform infrared spectroscopy (FTIR), …
Kinetics Study For Fischer-Tropsch Synthesis Over Cobalt Catalyst By Kinetic Monte-Carlo Simulation, Nuttawut Pugingna
Kinetics Study For Fischer-Tropsch Synthesis Over Cobalt Catalyst By Kinetic Monte-Carlo Simulation, Nuttawut Pugingna
Chulalongkorn University Theses and Dissertations (Chula ETD)
Kinetic Monte-Carlo simulation was utilized to study the kinetic behaviors of C₁ and C₂ formation in the Fischer-Tropsch synthesis over the cobalt surface by varying reaction conditions. Two reaction models: the carbide mechanism and the CO insertion mechanism were applied to this simulation. The production rates and fractional coverages of each adsorbed species could be calculated under the steady state. Moreover, the combination between carbide and CO insertion mechanism was also studied to suggest the possibility of each reaction mechanism, and compared the results with the reported experimental results under the same conditions. It was ob-served that the C–C bond …
Bespoke Discovery, Jessica M. Erickson
Bespoke Discovery, Jessica M. Erickson
Law Faculty Publications
The U.S. legal system gives contracting parties significant freedom to customize the procedures that will govern their future disputes. With forum selection clauses, parties can decide where they will litigate future disputes. With fee-shifting provisions, they can choose who will pay for these suits. And with arbitration clauses, they can make upfront decisions to opt out of the traditional legal system altogether. Parties can also waive their right to appeal, their right to a jury trial, and their right to file a class action. Bespoke procedure, in other words, is commonplace in the United States.
Far less common, however, are …
Association Of Legal Intervention Injuries With Race And Ethnicity Among Patients Treated In Emergency Departments In California, Aaron J. Rappaport, Alyssa C. Mooney, Shannon Mcconville, Renee Y. Hsia
Association Of Legal Intervention Injuries With Race And Ethnicity Among Patients Treated In Emergency Departments In California, Aaron J. Rappaport, Alyssa C. Mooney, Shannon Mcconville, Renee Y. Hsia
Faculty Scholarship
No abstract provided.
Understanding Why Women Stay: Examining Persistence Factors Of Women Majoring In Science And Technology Programs In Public Ethiopian Universities Using A Mixed Methods Design, Meseret Hailu
Electronic Theses and Dissertations
Amongst African nations, Ethiopia is a unique case in many respects. The country has the second largest population on the continent, is currently experiencing an economic boom, and is a relatively stable nation in the geopolitically volatile "Horn of Africa" region. In the past two decades, the higher education sector in Ethiopia has experienced rapid growth, as evidenced by an increase in both student enrollment and the number of universities. Amongst the various types of higher education institutions, public universities are especially important because they receive the greatest financial support from the Ministry of Education. Moreover, science and technology programs …
Introduction: For Better Or For Worse? Relational Landscapes In The Time Of Same-Sex Marriage, Michael W. Yarbrough
Introduction: For Better Or For Worse? Relational Landscapes In The Time Of Same-Sex Marriage, Michael W. Yarbrough
Publications and Research
As same-sex marriage has become a legal reality in a rapidly growing list of countries, the time has come to assess what this means for families and relationships on the ground. Many scholars have already begun to examine how marriage is helping some same-sex couples, but in this introduction I call for a broader and more critical research agenda. In particular, I argue that same-sex marriage crystallizes a key tension surrounding families and relationships in many contemporary societies. On the one hand, strict family norms are relaxing in many places, allowing more people to form more diverse types of caring …
Internationalization Strategies Of Service Sector Small And Medium Enterprises In Turkey, Aslihan Cakmak
Internationalization Strategies Of Service Sector Small And Medium Enterprises In Turkey, Aslihan Cakmak
Walden Dissertations and Doctoral Studies
Small and medium enterprises (SMEs) have a significant role in most emerging and developing economies. To increase the probability of survival of their SMEs and achieve sustainable growth, some SME leaders expand their business operations beyond national borders by implementing internationalization strategies. Internationalization is crucial to SME survival. The conceptual framework of this study consisted of a multitheory model including stage model, network theory, and new venture theory. The purpose of this qualitative multiple case study was to explore the strategies that Turkish information communication technology (ICT) SME leaders used to internationalize their business operations. Ten SME leaders, who led …
Diabetic Adult Access To Medical Care And Race And Ethnicity In Connecticut, Natacha Bertine Jerome
Diabetic Adult Access To Medical Care And Race And Ethnicity In Connecticut, Natacha Bertine Jerome
Walden Dissertations and Doctoral Studies
Diabetes is among the leading causes of death in Connecticut. An approximate of 330,000 adults in Connecticut have diabetes (diagnosed and undiagnosed). Those with diabetes have almost twice the risk of premature death throughout various age groups. The purpose of this cross-sectional study was to investigate whether disparities exist in access to medical care due to race and ethnicity; among adults with diabetes in the state of Connecticut. Furthermore, this study used the Andersen's behavioral model framework. Survey data from the behavioral risk factor surveillance system (BRFSS) were also analyzed. The research study covered 3 years (2013 to 2015) of …
Factors Predicting Academic Achievement Among Hispanic Community College Students, Lisa Marcelino
Factors Predicting Academic Achievement Among Hispanic Community College Students, Lisa Marcelino
Walden Dissertations and Doctoral Studies
Hispanic college students are more at risk of poor academic performance and dropping out than any other racial group. The Hispanic college population continues to grow, yet rates of retention and achievement for this group continue to decline. Previous research on Hispanic college students has examined factors that contribute to underachievement and declining graduation rates, but they are limited to students attending 4-year institutions. This study examined if grade point averages (GPAs) were affected by levels of self-efficacy, resiliency, and sensation seeking. Bandura's self-efficacy and social cognitive theories along with Zuckerman and Kuhlman's theory of sensation-seeking were the theoretical frameworks …
Information Technology Infrastructure: Global Economy And National Development In Haiti, Reynolds Alcena
Information Technology Infrastructure: Global Economy And National Development In Haiti, Reynolds Alcena
Walden Dissertations and Doctoral Studies
Political and environmental chaos recently experienced in Haiti has damaged the economic sector and telecommunication infrastructure. Developmental data from Haiti show 3 major trends: inadequate social and economic development, insufficient benefits from the global economy, and poorly planned information technology infrastructure (ITI). The specific problem addressed in this study is a knowledge gap in the views of stakeholders within Haiti's national culture on how the country's ITI can be developed to better engage Haiti in 21st century global and digital economy. The purpose of this qualitative case study was to explore the views of 48 expert participants regarding ITI development …
Asperger's Syndrome In African American Children, Suzette Bailey
Asperger's Syndrome In African American Children, Suzette Bailey
Walden Dissertations and Doctoral Studies
The prevalence of autism in the United States is 1 in 68 children. African American children are less likely to receive advance testing to confirm the diagnosis of Asperger's Syndrome (AS) compared to other ethnic groups. The purpose of this study was to determine if demographic factors (parental education level, family annual income, marital status of custodial parent(s), parent ethnicity, number of children in home, other children with disability, family location, mother age at time of birth, gender of child, birth status of child, adoption status and age, child order, and other disability) have any predictive relationship to AS diagnosis …
Teachers' Perceptions About Classroom Management Preparedness, Leslie Ellis
Teachers' Perceptions About Classroom Management Preparedness, Leslie Ellis
Walden Dissertations and Doctoral Studies
Undesirable student behaviors can disrupt classroom activities and can prevent instruction from taking place. At a local middle school, teachers lacked effective classroom management strategies to address undesirable student behaviors that impeded their abilities to instruct students. The purpose of this study was to explore teachers' perceptions about their classroom management preparation and to investigate professional development opportunities that may strengthen their skills in classroom management. Glasser's choice theory was used in this qualitative case study to explore perceptions of 10 teachers. The research questions focused on teachers' perceptions and experiences with effective classroom management practices, their perceptions of administrators' …
Winner, Best Appellate Brief In The 2018 Native American Law Student Association Moot Court Competition, Lianne T. Chung, Nicholas Ernst
Winner, Best Appellate Brief In The 2018 Native American Law Student Association Moot Court Competition, Lianne T. Chung, Nicholas Ernst
American Indian Law Review
No abstract provided.