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2019

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Articles 12571 - 12600 of 13032

Full-Text Articles in Physical Sciences and Mathematics

Organic Geochemical Characteristics Of Coal Deposits In Lampang Province, Patthapong Chaiseanwang Jan 2019

Organic Geochemical Characteristics Of Coal Deposits In Lampang Province, Patthapong Chaiseanwang

Chulalongkorn University Theses and Dissertations (Chula ETD)

ถ่านหินและหินตะกอนจำนวน 31 ตัวอย่างจากแหล่งถ่านหินแม่ตีบและแหล่งถ่านหินแม่ทานที่ตั้งอยู่ในจังหวัดลำปางทางตอนเหนือของประเทศไทยถูกนำมาศึกษาลักษณะเฉพาะทางธรณีเคมีอินทรีย์ (Organic geochemistry) ผลจากการวิเคราะห์ปริมาณสารอินทรีย์ทั้งหมด (Total organic carbon) พบว่าตัวอย่างถ่านหินจากแหล่งแม่ตีบมีค่าระหว่าง 30.12 - 73.71 wt. % และสูงกว่าตัวอย่างถ่านหินของแหล่งแม่ทานซึ่งมีค่าระหว่าง 23.48 - 52.50 wt. % หินดินดานจากทั้งสองแหล่งมีค่าใกล้เคียงกันระหว่าง 4.82 - 19.49 wt. % ในแหล่งแม่ตีบ และ 14.00 - 24.87 wt. % ในแหล่งแม่ทาน ค่าที่น้อยที่สุดของปริมาณสารอินทรีย์ทั้งหมดปรากฏในตัวอย่างหินโคลนซึ่งมีค่าระหว่าง 0.88 – 4.92 wt. % ในแหล่งแม่ตีบ และค่าระหว่าง 0.59 – 5.98 wt. % การวิเคราะห์ปริมาณสารอินทรีย์ที่สกัดได้ (Extractable organic matter) ในตัวอย่างหินของแหล่งแม่ตีบมีค่าระหว่าง 1,277 - 9,764 ppm ในขณะที่ตัวอย่างหินของแหล่งแม่ทานมีค่ามากกว่าโดยอยู่ระหว่าง 1,256-16,421 ppm จากข้อมูลข้างต้นทั้งสองแหล่งมีศักยภาพการเป็นชั้นหินต้นกำเนิดของแหล่งปิโตรเลียมอยู่ในเกณฑ์ดีถึงดีเยี่ยมยกเว้นหินโคลนบางตัวอย่าง ข้อมูลลักษณะเฉพาะทางธรณีเคมีอินทรีย์ศึกษาจากแก๊สโครมาโตแกรม (Gas chromatogram) ได้มาจากการวิเคราะห์โดยใช้เครื่องมือแก๊สโครมาโตกราฟี-แมสสเปกโตมิเตอร์ (Gas chromatography-mass spectrometer) ซึ่งให้ข้อมูลของตัวชี้วัดทางชีวภาพ (Biomarker and non-biomarker) ที่มีประโยชน์ในการตีความทั้งระดับความพร้อมสมบูรณ์ (Maturity) ชนิดของอินทรีย์วัตถุ (Organic matter input) และสภาพแวดล้อมการสะสมตัวในอดีต (Depositional environment) ในการศึกษานี้ถ่านหินมีระดับความพร้อมสมบูรณ์เทียบเคียงกับระดับถ่านหิน (coal rank) อยู่ในระดับลิกไนต์ถึงบิทูมินัสสารระเหยสูงระดับซี (Lignite – high volatile bituminous C) อ้างอิงจากตัวชี้วัดความพร้อมสมบูรณ์ทางชีวภาพ (Biomarker maturity) ซึ่งบ่งชี้ว่าตัวอย่างหินมีระดับความพร้อมสมบูรณ์อยู่ในระดับตอนต้น (immature-early mature stage) แก๊สโครมาโตแกรมของแอลเคนสายตรง (n-alkanes) …

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Geology And Mineralization Characteristics Of Epithermal Gold, Suwan Prospect, Changwat Phitsanulok, Tanad Soisa Jan 2019

Geology And Mineralization Characteristics Of Epithermal Gold, Suwan Prospect, Changwat Phitsanulok, Tanad Soisa

Chulalongkorn University Theses and Dissertations (Chula ETD)

The Suwan prospect is located about 6 km northwest of the Chatree gold mine in Phitsanulok province, central Thailand. Gold-silver mineralization occurs as veins and stockworks hosted in volcaniclastic and volcanogenic-sedimentary rocks of Late Permian- Early Triassic age which is classified as a low sulfidation epithermal deposit base on mineralization texture, alteration pattern and sulfide mineral assemblages. From top to bottom, the hosted volcanic succession can be divided into 3 units, namely 1) Felsic volcanic unit (Unit 1), 2) Volcanogenic-sedimentary unit (Unit 2), and 3) Porphyritic andesite unit (Unit 3). Unit 1 consists predominantly of quartz-rich fiamme breccia, lithic-rich fiamme …

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Terrain Analysis In Phetchabun Province, Tanapat Pichetsopon Jan 2019

Terrain Analysis In Phetchabun Province, Tanapat Pichetsopon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Phetchabun province, lower northern Thailand is vulnerable to geohazards, landslide and flooding with the potential for significant harm to people and property. In addition, Phetchabun province has many lineaments that could be potential source of tectonic activities. In this study, terrain analysis techniques are used through 30 meters resolution Digital Elevation Model (DEM) data in order to determine geomorphic indices related to tectonic activity. The statistic index method (Si) is calculated in relation of six parameters to indicate landslide susceptible area. and the hydromorphometric contrast index (HCI) is used to identify sensitive area to flooding by evaluating five parameters. According …

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Color Enhancement Of Tourmaline By Electron Beam Irradiation, Waratchanok Suwanmanee Jan 2019

Color Enhancement Of Tourmaline By Electron Beam Irradiation, Waratchanok Suwanmanee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Tourmaline is a semi-precious stone that is quite popular in gem market. Red-purple tourmaline, so-called “Rubellite”, is particularly famous. Consequently, pink tourmalines have recently been enhanced by gamma radiation to intensify color as rubellite. In this study, an electron beam technique was applied for experimental treatment. Moreover, gamma ray irradiation was also applied to treat the same sample collection for comparison. Color enhancement was designed for both radiations at three levels of doses, i.e., 400, 800, and 1,200 kilogreys. Pink and green tourmalines from Nigeria were collected for the experiment. Each sample was cut into two tablets for experimental irradiations …

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Suid Fossils And Sedimentology From The Chaloem Phra Kiat And Phimai Sandpits, Nakhon Ratchasima Province, Thunchanok Kawinate Jan 2019

Suid Fossils And Sedimentology From The Chaloem Phra Kiat And Phimai Sandpits, Nakhon Ratchasima Province, Thunchanok Kawinate

Chulalongkorn University Theses and Dissertations (Chula ETD)

The suid fossils were recorded in fluvial sediments at the Chaloem Phra Kiat and Phimai Districts, Nakhon Ratchasima Province. In this study, numerous suid fossils were identified systematically by the measurement and description in detail of the external morphology of teeth, and comparison with other related species. Sedimentary facies and facies association from stratigraphy of fluvial depositional environment from sandpits have also been studied. As a result, sediments from Chaloem Phra Kiat and Phimai sandpits comprise very fine to coarse-grained sand with dominate sedimentary structures of the fluvial deposits. The cumulative stratigraphical thickness of the studied successions was 12-15 m. …

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Reconstruction Of Sea Level Fluctuation And Environmental Change In Khao Sam Roi Yot National Park, Changwat Prachuap Khiri Khan During The Late Holocene, Worakamon Nudnara Jan 2019

Reconstruction Of Sea Level Fluctuation And Environmental Change In Khao Sam Roi Yot National Park, Changwat Prachuap Khiri Khan During The Late Holocene, Worakamon Nudnara

Chulalongkorn University Theses and Dissertations (Chula ETD)

The Gulf of Thailand is generally provided the efficiency evidences of sea level fluctuation according to the lack of tectonic events. Sam Ro Yot National Park (SRY) is located in the west coast of the Gulf of Thailand with its elevation approximately at sea level. Sedimentary sequences from SRY wetland has been obtained. This sedimentary sequence can be divided into 3 units, comprised dark grey silty to sandy clay of unit A, beige clay of unit B, and gyttja sediment of unit C. An intensive analysis was focused on core CP-4 because it is the longest core and compose of …

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Inhalation Exposure And Urinary Level Of Heavy Metals Of Electronic Waste Dismantling Workers In Buriram, Thailand., Panvarong Wongsabsakul Jan 2019

Inhalation Exposure And Urinary Level Of Heavy Metals Of Electronic Waste Dismantling Workers In Buriram, Thailand., Panvarong Wongsabsakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

The main objective of this study was to assess the health risk of electronic waste dismantling workers exposed to heavy metal (As, Cd, Cr, Cu, Pb, Ni, Mn, and Zn) in PM10 using urinary heavy metals as a biomarker. The levels of heavy metals in the urine of non- and e-waste dismantling workers in consequence of the exposure to heavy metals in PM10 were investigated at Daengyai sub-district, Banmaichaiyapot district, and Banpao sub-district, Phutthaisong district, Buriram province, from February to March 2019. A face-to-face interview using a questionnaire was carried out to get additional information from the target participants. The …

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Pm2.5, Pm10 Air Pollution And Associated Heavy Metals In Traffic Congested And Construction Areas Of Bangkok, Paphinwit Thammasaroj Jan 2019

Pm2.5, Pm10 Air Pollution And Associated Heavy Metals In Traffic Congested And Construction Areas Of Bangkok, Paphinwit Thammasaroj

Chulalongkorn University Theses and Dissertations (Chula ETD)

The capital city of Thailand, Bangkok, is facing a serious problem caused by overpopulation and traffic congestion. In the this work, particulate matter, both PM2.5 (diameter < 2.5 μm) and PM10 (diameter < 10 μm) were quantified at the road nears construction areas and road with high traffic; compared with a control area. The sampling area comprised of Pattanakarn Road and Srinagarindra Road located on the eastern route, located between the inbound and outbound junction. Mini-volume air sampler was used to collect PM2.5, while cyclone air samplers were used to collect PM10. The samples were collected from November to December 2018, for 12 hours per day for 5 days at each sites. The collected samples were then digested by using microwave digestion for heavy metal components like Fe, Cu, Zn, Cd and Pb. Then, they were analyzed by Graphite Furnace Atomic Absorption Spectrometry (GFAAS) to quantify the heavy metal concentrations. Video recorders were installed at each sampling areas to monitor the traffic flow and it was found that construction areas were the most crowded. The average PM2.5 and PM10 concentrations in the construction areas were higher than those in traffic areas with no construction and the background site (a park), which had no impacts from construction and traffic. Heavy metals associated with particulate matter emitted during construction activities is an emerging environmental issue; however, construction activities are required for convenience and development. This study provides important data required to monitor the future trends of air pollution sources.

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Adsorption Of Haloacetonitriles By Carbonized Metal-Organic Frameworks, Phattarawarin Rodbutr Jan 2019

Adsorption Of Haloacetonitriles By Carbonized Metal-Organic Frameworks, Phattarawarin Rodbutr

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research investigated adsorption efficiency of four including; Chloroacetonitrile (MCAN), Dichloriacetonitrile (DCAN), Bromoacetonitrile (MBAN) and Dibromoacetonitrle (DBAN) on five acid-washed carbonized metal-organic frameworks (MOFs) (WC-ZIF-8, WC-MIL-53, WC-MIL-88B, WC-UiO-66 and WC-HKUST-1) compared with powder activated carbon (PAC S10). The synthesized materials were characterized by XRD, SEM-EDS, nitrogen adsorption isotherms, FTIR and XPS. The screening experiment revealed that WC-MIL-88B, WC-ZIF-8, and PAC had highest adsorption capacities for four HANs, respectively. The HANs molecular size and their hydrophobicity influenced the adsorption rates of HANs in the order of DBAN>DCAN>MBAN>MCAN. The adsorption isotherms showed that Di-halogenic HANs (DBAN and DCAN) can …

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A Market-Based Probabilistic Risk Assessment Of As Concentration In Raw And Cooked Rice In Bangkok, Supanad Hensawang Jan 2019

A Market-Based Probabilistic Risk Assessment Of As Concentration In Raw And Cooked Rice In Bangkok, Supanad Hensawang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Rice is a staple food of human and can be a main source of arsenic (As) exposure. This study was conducted to i) investigate the concentrations of total, inorganic and bioaccessible of As in raw rice, ii) investigate the effects of rice processing before human consumption on the concentrations of As in rice, and iii) evaluate the potential health impacts of As exposure through rice consumption. A total of 208 polished and non-polished samples sold in the local markets of Bangkok were collected. The total As concentrations in polished (0.0878 to 0.2949 mg kg-1, n = 154) and non-polished (0.1187 …

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Long-Time Behavior Of A Nonlocal Dispersal Equation, Aussacha Dintawong Jan 2019

Long-Time Behavior Of A Nonlocal Dispersal Equation, Aussacha Dintawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, study the nonlocal dispersal equation [equation] with a non-homogeneous boundary condition. We generalize the result of J.W. Sun (2015), where in this work the kernel J has a non-compact support. The global well-posedness and comparison principles (both time-dependent and stationary problems) are established. The main result is the long-time behavior of solutions, which is proved to depend on the boundary data.

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Augmented Sensors For Particulate Matter Concentration Prediction Using Supervised Learning Models, Chadaphim Photphanloet Jan 2019

Augmented Sensors For Particulate Matter Concentration Prediction Using Supervised Learning Models, Chadaphim Photphanloet

Chulalongkorn University Theses and Dissertations (Chula ETD)

Particulate matter concentration prediction models have been researched, developed, and applied to data from various topography around the world. The characteristics of different topography make a model suitable for each specific topography. This dissertation proposes a novel method to predict particulate matter concentration with a diameter smaller than 10 microns in Nan Province of Thailand that integrates feature selection method, supervised learning model, and modified depth-first search algorithm. Unlike the traditional supervised learning models, the proposed method is able to accept multi-dimensional data as input which consist of particulate matter concentration, air pollutants, and air qualities. These features are the …

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Uniform Distribution Of Fractional Parts Of Average Of Kth Power Of Prime Divisors, Chitpanu Chairatanagul Jan 2019

Uniform Distribution Of Fractional Parts Of Average Of Kth Power Of Prime Divisors, Chitpanu Chairatanagul

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we prove that for every positive integer k greater than or equal to two, the sequence of the fractional parts of the arithmetic mean of the kth power of prime divisors of n counted with or without multiplicity, as n runs through all positive integers, is uniformly distributed modulo one.

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Boundaries Of Overlapping Reuleaux Triangles, Jirapat Kaewkam Jan 2019

Boundaries Of Overlapping Reuleaux Triangles, Jirapat Kaewkam

Chulalongkorn University Theses and Dissertations (Chula ETD)

where R1 and R2 are two congruent Reuleaux triangle such that Int(R1)∩Int(R2) ̸= ∅. Denote ∂Ri and Int(Ri) the boundary and the interior of Ri , respectively. We finish the proof when R2 is a translated copy R1 and we obtain some interesting results when R1 and R2 intersect in general position.

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Spectra Of Unitary Cayley Graphs Of Matrices Over Finite Commutative Rings, Jitsupat Rattanakangwanwong Jan 2019

Spectra Of Unitary Cayley Graphs Of Matrices Over Finite Commutative Rings, Jitsupat Rattanakangwanwong

Chulalongkorn University Theses and Dissertations (Chula ETD)

For a finite ring R with identity, the unitary Cayley graph of R, CR, is the graph with vertex set R and for each x, y ∈ R, x and y are adjacent if and only if x − y is a unit of R. In this thesis, we determine some eigenvalues of CMn(F) , where F is a finite field, by using the additive characters and use these eigenvalues to analyze strong regularity, hyperenergetic graphs and Ramanujan graphs. Next, we extend the results to CMn(R) , where R is a local ring. We characterize all local rings R and …

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Classification Of Aircraft With Shadow Using Keypoint Descriptor From Remote Sensing Images, Natnicha Meeboonmak Jan 2019

Classification Of Aircraft With Shadow Using Keypoint Descriptor From Remote Sensing Images, Natnicha Meeboonmak

Chulalongkorn University Theses and Dissertations (Chula ETD)

Presently, aircraft classification from remote sensing images is widely used in military and civilian. However, aircraft type classification is still challenging to discriminate. The reason is that the aircraft displayed in the image has different in color, shape, size, and orientation. Moreover, there is the shadow appeared over and behind the aircraft that obscures some details of aircraft. Therefore, this work proposes the classification of aircraft with shadow method. This method modifies the deeply supervised salient object detection with short connections to make the aircraft be outstanding from the shadow and other objects in the background and then segment it. …

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Development Of Facial Expression Detection Model For Stroke Patients, Rawinan Praditsangthong Jan 2019

Development Of Facial Expression Detection Model For Stroke Patients, Rawinan Praditsangthong

Chulalongkorn University Theses and Dissertations (Chula ETD)

A stroke patient should be cared and treated closely since the patient cannot speak, communicate, and move the body when needed. In addition, the number of stroke patients is increasing in Thailand and around the world. Unfortunately, the number of medical staffs does not vary by the number of stroke patient. Thus, the aim of this research is to develop a facial expression detection model for stroke patients during their treatments. This research proposes the facial expression detection model for stroke patients from facial features, such as Interpalpebral Fissure (IPF), Palpebral Fissure Length (PFL), Palpebral Fissure Region (PFR), Inner Brow …

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Generalized Topologies Induced By Monotonic Maps And Hereditary Classes, Sahawat Wongkhunen Jan 2019

Generalized Topologies Induced By Monotonic Maps And Hereditary Classes, Sahawat Wongkhunen

Chulalongkorn University Theses and Dissertations (Chula ETD)

It is shown in [3] that every generalized topology can be extended to a new one by using hereditary classes, called a generalized topology via a hereditary class. Following [5], the continuity on generalized topological spaces via hereditary classes was studied. In this thesis, we introduce the notion of generalized topological spaces induced by monotonic maps and hereditary classes and provide some of their properties. Also, we define and study the continuity on generalized topological spaces induced by monotonic maps and hereditary classes in various situations. Finally, we study some properties and characterizations of generalized topological spaces induced by monotonic …

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Solving Interval-Valued Returns Mean Absolute Deviation Portfolio Selection Model Under Basis Stability, Songkomkrit Chaiyakan Jan 2019

Solving Interval-Valued Returns Mean Absolute Deviation Portfolio Selection Model Under Basis Stability, Songkomkrit Chaiyakan

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work discusses a portfolio selection model with interval linear programming arising from the uncertainty of future rates of return and the disagreement over their estimates. The risk of the overall portfolio is proposed as an objective function to obtain a well-diversified portfolio with a certain threshold rate of return. The optimization problem employs mean absolute deviation as a risk measure for the sake of risk diversification and time complexity. The possible ranges of optimal portfolio returns and associated risks are derived. The duality theory contributes to an enclosure of the optimal portfolios. When the bounds on future rates of …

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Aircraft Detection Using Single Shot Scale-Invariant Face Detector With Viridis Saliency Map From Remote Sensing Image, Teepakorn Lilek Jan 2019

Aircraft Detection Using Single Shot Scale-Invariant Face Detector With Viridis Saliency Map From Remote Sensing Image, Teepakorn Lilek

Chulalongkorn University Theses and Dissertations (Chula ETD)

Aircraft detection from remote sensing images is a useful task and essential in many fields; for example, in the military, aircraft detection systems are used to search and inspect an enemy aircraft from remote sensing images. Nowadays, aircraft detection from remote sensing images has gained increasing research attention because this task is very challenging. This task is difficult due to many occurred problems in remote sensing images, such as a shadow, a complicated background, and various aircraft scales. In this research, we create a Viridis saliency map using many techniques from image processing such as color mapping, morphological image processing, …

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Logo Classification Of Amphetamines By Surf And Bag-Of-Features Model, Tharaphon Nitijiramon Jan 2019

Logo Classification Of Amphetamines By Surf And Bag-Of-Features Model, Tharaphon Nitijiramon

Chulalongkorn University Theses and Dissertations (Chula ETD)

An amphetamine is one of the drugs apprehended by the policemen in Thailand. At present, when an amphetamine drug seller is arrested, captured amphetamines are sent to the Scientific Crime Detection Center Region 1 to identify the amphetamines' source. Each drug is classified based on the printed character to relevant information from the source of drugs. For each case, a large volume of drugs is sent to be classified by only three staff members. It is a time-consuming task. In this work, we propose a framework for classifying the image of amphetamines based on their logo using the SURF and …

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Formaldehyde Fluorescent Sensors From 1,8-Naphthalimide Derivatives, Apicha Maharat Jan 2019

Formaldehyde Fluorescent Sensors From 1,8-Naphthalimide Derivatives, Apicha Maharat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Three derivatives of 1,8-naphthalimide were systematically designed and synthesized to investigate the effect of substitution pattern on their photophysical properties and sensing behaviors towards formaldehyde in aqueous media. The key substituents, the hydrazino (-NHNH2) and the 2-methoxyethylamino groups (-NHCH2CH2OCH3), were installed at the 4-position of 1,8-naphthalimide by a nucleophilic replacement, and at the imide position by a condensation reaction with 1,8-naphthalic anhydride precursor. All target compounds were obtained in good overall yields of 60-80%. Compounds with two hydrazine moieties (R3) showed excellent selective fluorescent responses towards formaldehyde with the 3.5-fold fluorescence enhancement in 5% aqueous acetic acid solution at 520 …

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Polyvinyl Alcohol/Starch Modified Cotton Thread For Glucose Distance-Based Colorimetric Detection, Pornchanok Punnoy Jan 2019

Polyvinyl Alcohol/Starch Modified Cotton Thread For Glucose Distance-Based Colorimetric Detection, Pornchanok Punnoy

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, polyvinyl alcohol (PVA) and starch modified cotton thread was developed as a cotton thread-based device for distance-based colorimetric detection of hydrogen peroxide (H2O2) and glucose. PVA and starch, the biocompatible polymers, were modified on a cotton thread to enhance the enzymatic stability and reagent immobilization efficiency. The colorimetric glucose detection of the device was based on a bienzymatic reaction involving glucose oxidase (GOx) and horseradish peroxidase (HRP), incorporated with potassium iodide (KI) as an indicator, which was oxidized by H2O2 to provide blue-black color band of an iodine–starch complex. The length of color band on the cotton …

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Continuous Flow Selective Hydrogenation Of 5-Hydroxymethylfurfural To 2.5-Dimethylfuran Using Pd-Cu/Reduced Graphene Oxde Catalysts, Sareena Mhadmhan Jan 2019

Continuous Flow Selective Hydrogenation Of 5-Hydroxymethylfurfural To 2.5-Dimethylfuran Using Pd-Cu/Reduced Graphene Oxde Catalysts, Sareena Mhadmhan

Chulalongkorn University Theses and Dissertations (Chula ETD)

2,5-Dimethylfuran (DMF) has been considered a promising biofuel, potentially derived from biomass. There have been various reports on DMF production from hydrogenation of 5-hydroxymethylfurfural (HMF). However, most reports employed high hydrogen pressure, long reaction times, and reactions under batch reactor. In this study, Pd-Cu bimetallic catalysts incorporated on reduced graphene oxide (RGO) were used for hydrogenation of HMF to DMF using 2-propanol as hydrogen donor under continuous flow system. Synthesized catalysts were characterized by N2 physisorption, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and temperature programmed reduction of hydrogen …

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Preparation Of Starch-Filled Polyisocyanurate Foams Catalyzed By Zinc-Ammonia Complex/Potassium Octoate, Sirima Goonack Jan 2019

Preparation Of Starch-Filled Polyisocyanurate Foams Catalyzed By Zinc-Ammonia Complex/Potassium Octoate, Sirima Goonack

Chulalongkorn University Theses and Dissertations (Chula ETD)

The research aimed to reduce apparent density and improve fire resistance of polyisocyanurate (PIR) foam. PIR foams were prepared using zinc-ammonia complex and potassium octoate as catalyst for gelling/blowing and trimerization reactions, respectively. Three types of starch produced in Thailand, namely glutinous rice flour, rice flour and mung bean starch, were used as additives for PIR foams. The characterized properties of PIR foams modified with starches are reaction times (cream time, gel time, rise time and tack free time), polyisocyanurate/polyurethane (PIR/PUR) ratio, %isocyanate conversion, apparent density, compressive property, morphology and fire behavior. These properties are compared with PIR foam without …

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Magnetic Nanoparticles Stabilized By Phosphorylcholine-Containing Polymer For Antibody Free C-Reactive Protein Detection, Suttawan Saipia Jan 2019

Magnetic Nanoparticles Stabilized By Phosphorylcholine-Containing Polymer For Antibody Free C-Reactive Protein Detection, Suttawan Saipia

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aims to develop a simple, yet effective assay for C-reactive protein (CRP) detection based on a combination of magnetic separation and antibody-free colorimetric assay. Magnetic nanoparticles stabilized with phosphorylcholine-containing polymer, poly[methacrylic acid)-ran-(methacryloyloxyethyl phosphorylcholine)] (PMAMPC-MNPs) were prepared by co-precipitation of ferric and ferrous salts in the presence of PMAMPC. Carboxyl groups in the methacrylic acid (MA) repeat units chelate with Fe atoms during MNPs formation while the methacryloyloxyethyl phosphorylcholine (MPC) repeat units provide specifically binding sites and conjugate with CRP in presence of Ca2+. The PMAMPC-MNPs were characterized by ATR-FTIR, TEM, DLS, TGA and XRD. To determine the CRP …

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High Magnification Polymeric Lens For Smartphone Microscope, Wisansaya Jaikeandee Jan 2019

High Magnification Polymeric Lens For Smartphone Microscope, Wisansaya Jaikeandee

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, we present a facile method for fabrication of plano-convex lenses, using high reflective optical polymer (Polydimethylsiloxane, Sylgard 184 by Dow Corning, n ~1.42 and Norland Optical adhesive 61, NOA61 by Norland Products, ~1.56) under the confined sessile drop technique. The confined sessile drop technique is a facile method and an adjustable lens geometry through controlled the weight of liquid polymer on the lens substrate, as PMMA circular disk and Sylgard circular disk, with different diameter (2.5-6.0 mm). The liquid polymer was gradually spread and radially over the surface of the lens substrate, and resistance to spreading of …

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Curling Probe Measurement In Plasma, Chatchai Sirithipvanich Jan 2019

Curling Probe Measurement In Plasma, Chatchai Sirithipvanich

Chulalongkorn University Theses and Dissertations (Chula ETD)

The curling probe is one of the active resonance absorption spectroscopic methods, the methods utilized the probe reflection coefficient spectrum to determine the plasma density. The proposed model of the curling probe uses the deviation of the most matched frequency, the frequency in which the minimum reflection coefficient occurs, when the probe is submerged in different mediums. The probe structure is simple and claimed to be robust and efficient. The experiments of a curling probe were performed and the simulations for the probe reflection coefficient for both previously reported probe and the constructed probe configuration have been conducted. The previously …

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Ads₄/Cft₃ Holography From Four-Dimensional Gauged Supergravity, Khem Upathambhakul Jan 2019

Ads₄/Cft₃ Holography From Four-Dimensional Gauged Supergravity, Khem Upathambhakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

We study holographic RG flows from N = 3 and N = 4 gauged supergravities in four dimensions. The scalar manifold of N = 3 gauged supergravity is in the form of the coset space G/H = SU(3, n)/SU(3) × SU(n) × U(1). Possible gauge groups, in this study, are given by SO(3) × SO(3), SO(3, 1), SO(2, 2), SO(2, 1) × SO(2, 2), and SL(3, R). We then study N = 4 gauged supergravity from type II compactification on T⁶/Z₂ × Z₂ with non-semisimple gaugings. The scalar manifold of N = 4 gauged supergravity is in the form of …

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Multipole Resonance Probe Measurement In Plasma, Natthapong Jampaiboon Jan 2019

Multipole Resonance Probe Measurement In Plasma, Natthapong Jampaiboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Active plasma resonance spectroscopy (APRS) is one of the interesting methods which could avoid plasma contamination problem occurs in a conventional Langmuir probe measurement. It is because the probe conductors are covered by a dielectric material. The APRS probe can be of any shape. A multipole resonance probe is a hemisphere APRS probe since a sphere imposes the simplest way to find an analytical solution by solving the Laplace equation in the spherical coordinates with the azimuthal symmetry. In this study, the APRS probes in the hemisphere, microstrip, and parallel rod shapes were constructed. Plasma density was obtained by using …

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