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2020

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Articles 14581 - 14610 of 14752

Full-Text Articles in Physical Sciences and Mathematics

Generalized Factorizability Of Certain Implicit Dependence Copulas, Peerapong Panyasakulwong Jan 2020

Generalized Factorizability Of Certain Implicit Dependence Copulas, Peerapong Panyasakulwong

Chulalongkorn University Theses and Dissertations (Chula ETD)

The copula CX,Y of random variables X and Y that are uniformly distributed on [0,1] is called an implicit dependence copula if f(X)=g(Y) almost surely for some Borel functions f and g on [0,1]. Via a generalized Markov product, we give a one-to-one correspondence between the implicit dependence copulas and the parametric classes of subcopulas on a corresponding domain for the cases that f=g=Λθ, the tent function whose top is at (θ,1). We also show in the case f=g=α, a simple measure-preserving function, that implicit dependence copulas are generalized factorizable.

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Hydromorphological Changes Of Chi River, Mueang District, Khon Kaen Province, Pawat Wattanachareekul Jan 2020

Hydromorphological Changes Of Chi River, Mueang District, Khon Kaen Province, Pawat Wattanachareekul

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis focuses on the analysis of hydrology coupled with geomorphology for river management such as flood mitigation and river restoration. Morphological Quality Index (MQI) is used for assessing hydro-morphological conditions from part of the Chi River (67 km long) at Khon Kaen province, a major river in north-eastern Thailand. This study area has been suffering from unexpected and repeated flooding. MQI is applied to evaluate the degree of hydro-morphological alteration in terms of relative scores (from 0 to 1). Basically, in case that MQI score equals 1, it means the area has no any alteration. On the other hand, …

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Classification Of Main Components In Airports From Remote Sensing Images By Efficient Network, Pimpisa Charoenchittang Jan 2020

Classification Of Main Components In Airports From Remote Sensing Images By Efficient Network, Pimpisa Charoenchittang

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we classify the type of main components in airports from the remote sensing images. This datasets is considered as an interesting information since the same type of component may have different shape, size, and color. EfficientNet architecture is the deep learning architecture to use in this research due to the small number of parameters and computational time compared to the other architectures with similar accuracy. In our experiment, we apply the EfficientNet in versions B0, B1, B2, B3, and B4 to classify four types of components in the airport; the passenger terminal, the radio tower, the runway, …

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Cops And Robbers On Hypergraphs, Pinkaew Siriwong Jan 2020

Cops And Robbers On Hypergraphs, Pinkaew Siriwong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cops and robbers game is a game usually played on a finite connected graphwith two players, cop and robber. Recently, cops and robbers game played on hypergraphs was introduced. To give a better chance to a cop by allowing morethan one cop and at least one cop has to move, the cop-number, the least numberof cops to guarantee that they win the game, on graphs and hypergraphs is studied.This thesis provides (i) a characterization of a cop-win hypergraph (ii) some results on the products of hypergraphs and (iii) the cop-number of complete k-partite hypergraphs and n-prisms over a hypergraph. Moreover, …

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Pyrrolidinyl Peptide Nucleic Acid Probe Capable Of Crosslinking With Dna, Penthip Muangkaew Jan 2020

Pyrrolidinyl Peptide Nucleic Acid Probe Capable Of Crosslinking With Dna, Penthip Muangkaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

DNA interstrand cross-linking (ICL) is a phenomenon in which two strands of the DNA (most often as part of the same DNA duplex) bind together via a covalent bond. This process prevents the DNA strand dissociation, which is essential for its biological functions, and thus is extremely damaging to cells. To overcome the problem of non-specificity associated with general DNA cross-linking agents, a cross-linkable probe in which the reactive group is placed on the probe that can specifically recognize part of the DNA target. The strong binding affinity and biological stability of the pyrrolidinyl peptide nucleic acid (acpcPNA) inspired us …

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Graph And Number Theoretic Properties Of Certain Maps Over Finite Field, Pratchayaporn Doemlim Jan 2020

Graph And Number Theoretic Properties Of Certain Maps Over Finite Field, Pratchayaporn Doemlim

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we study the graph over a finite field $\mathbb{F}_q$, where $q$ is a prime power, obtained by iterations of the map $g(x)=x^p$, where $p$ is a prime number. Some properties of the graphs such as a characterization of their vertices and the number of cycles with specific length are showed. Moreover, some statistical estimates about the tail and cycle lengths of the related graphs are established.

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Fabrication Of Sno2 Layer As Electron Transport Layers For Perovskite Solar Cells, Rattanaphon Thanimkan Jan 2020

Fabrication Of Sno2 Layer As Electron Transport Layers For Perovskite Solar Cells, Rattanaphon Thanimkan

Chulalongkorn University Theses and Dissertations (Chula ETD)

A SnO2 has attracted more attention as electron transport layer (ETL) for perovskite solar cells (PSCs) because it has diverse advantages, e.g., wide bandgap energy, excellent optical and chemical stability, high transparency, high electron mobility, and easy preparation. In this work, SnO2 layer was fabricated by spin-coating and RF magnetron sputtering techniques with various conditions. The SnO2 layer was integrated into the planar structure of PSCs consisting of FTO/SnO2/MAPbI3/spiro-OMeTAD/Au. For spin-coating, SnO2 films can fully cover the FTO, but it has some particulates from recrystallization of SnO2 precursor as observed in the FESEM images. For RF sputtering technique, morphology of …

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Anti-Oxidant And Anti-Inflammatory Compounds From Magnolia Liliifera (L.) Baill. Flower And Dendrobium Signatum Rchb.F., Prajak Khumploy Jan 2020

Anti-Oxidant And Anti-Inflammatory Compounds From Magnolia Liliifera (L.) Baill. Flower And Dendrobium Signatum Rchb.F., Prajak Khumploy

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, a purification of the EtOAc crude extract of Dendrobium signatum Rchb.f. aerial parts was performed fifteen compounds (1-15) and the hexane crude extracts of Magnolia liliiferra (L.) Baill. were further isolated to accomplish three compounds (16-18). They yielded one new picrotoxane sesquiterpene, 7-hydroxydendroterpene B (2) and a new a-pyrone, (-)-6R-signatone (4), along with sixteen known compounds. These included dendroxine (1), crystallinin (3), dendrocandin B (5), dendrocandin I (6), 6''-de-O-methyldendrofindlaphenol A (7), p-hydroxyphenylethyl-p-coumarate (8), 3,4-dihydroxy-5,4'-dimethoxybibenzyl (9), 3-methoxy-5-[2-(4-methoxyphenyl) ethyl]phenol (10), 4,4'-dihydroxy-3,5-dimethoxybibenzyl (11), naringenin (12), (2S)-homoeridodictyol (13), (2S)-homohesperetin (14), (-)-syringaresinol (15), (+) sesamin (16), (+) fargesin (17) and (-) kobusin …

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Tetrabromomethane-Mediated Desulfurization For Synthesis Of Isothiocyanates From Amines, Saharat Techapanalai Jan 2020

Tetrabromomethane-Mediated Desulfurization For Synthesis Of Isothiocyanates From Amines, Saharat Techapanalai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Isothiocyanate considered as an important building block for pharmaceutical industry. Traditional methods for preparation of isothiocyanate involved the desulfurization of dithiocarbamate salt from amine using oxidizing agent. Although those methods are efficient, however, all of them require the use of toxic reagent, strong oxidizing agent, multiple step synthesis, harsh condition and large amount of metal catalyst. Therefore, in this research, we develop two mild methods to synthesize isothiocyanates from amines using low toxic reagent. For the first process, we were able to demonstrate the use of photocatalyst, safranin O to convert dithiocarbamate salt of 4-bromoaniline into 4-brophenyl isothiocyanate in 48% …

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Geology And Petrochemistry Of Volcanic Rocks In The Lam Sonthi Area, Lop Buri Province, Saowaphap Uthairat Jan 2020

Geology And Petrochemistry Of Volcanic Rocks In The Lam Sonthi Area, Lop Buri Province, Saowaphap Uthairat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Lam Sonthi area is in Lop Buri province, central Thailand. Stratigraphically, the geology of the area consists of five rocks units; Unit I: Khao Ruak siltstone which is correlated to Khao Luak Formation (Early Permian), Unit II: Khao Phaeng Ma conglomerate, Unit III: Khao Ruak volcanics, Unit IV: Lam Sonthi polymictic conglomerate, and Unit V: Kuttaphet sandstone which is correlated to Phu Kradung Formation (Early Jurassic). In addition, the volcanic rocks, which are named as Kuttaphet volcanics and Khok Khli volcanics, could be found in the top of Unit IV as the polymictic intermediate breccia. Petrographic classification identifies the volcanic …

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Harmonic Analysis Of Riesz-Type Transforms Arising In Nonlocal Partial Differential Equations, Sasikarn Yeepo Jan 2020

Harmonic Analysis Of Riesz-Type Transforms Arising In Nonlocal Partial Differential Equations, Sasikarn Yeepo

Chulalongkorn University Theses and Dissertations (Chula ETD)

where s ∈ (0, 1) and g is a given function, has been widely studied under different assumptions on the kernel K. In this work, we introduce an operator associated to the above nonlocal equation via Riesz potential. Under assumptions that K is measurable, symmetric and elliptic, we obtain that such an operator is a CalderónZygmund operator

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Graph Grabbing Games And Toucher-Isolator Games, Sopon Boriboon Jan 2020

Graph Grabbing Games And Toucher-Isolator Games, Sopon Boriboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, we study the graph grabbing game and the Toucher-Isolator game. In the graph grabbing game, we partially confirm a conjecture of Seacrest and Seacrest which states that Alice wins the game on every weighted connected bipartite even graph. In the Toucher-Isolator game, we give a simple alternative proof of a result of Räty that determines the most suitable tree on n vertices for Toucher which answers a question of Dowden, Kang, Mikalački and Stojaković.

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Synthesis Of 5-Phenoxyprimaquine Derivatives And Their Tetraoxane Conjugates As Anti-Malarial Agents, Somruedee Jansongsaeng Jan 2020

Synthesis Of 5-Phenoxyprimaquine Derivatives And Their Tetraoxane Conjugates As Anti-Malarial Agents, Somruedee Jansongsaeng

Chulalongkorn University Theses and Dissertations (Chula ETD)

Currently, the development of the new anti-malarial drug for the treatment of the increasing drug-resistant strains of malaria was necessary. Therefore, this research was performed by synthesis and evaluation of their antimalarial activity for the development of primaquine which currently was used for anti-malarial drug. The substituents group on 5-phenoxyprimaquine derivatives which had the highest therapeutic index and less toxicity than primaquine were emphasized. The effect of substituted group at para position was studied. Three new derivatives with CN (7e), CF3 (7g), CONH2 (7h) substituents, and five known derivatives with OMe (7b), Br (7c), Cl (7d), F (7f) substituents and …

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Anti-Proliferative Metabolites From The Root Of Calophyllum Inophyllum L., Syahadatain Nor Haerani Jan 2020

Anti-Proliferative Metabolites From The Root Of Calophyllum Inophyllum L., Syahadatain Nor Haerani

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to isolate secondary metabolites from the root of C. inophyllum L. and to evaluate their anti-proliferative activities against hepatocellular carcinoma and colorectal cancer cells. Chromatographic fractionation of the n-hexane and ethyl acetate crude extracts led to the isolation of two new (1 and 2) and twelve known xanthones (3-14). In addition, metabolites 4, 6 and 8 were isolated from the genus Calophyllum for the first time. All metabolites were evaluated for their anti-proliferative activity against Hep-G2 and HCT-116 cell lines. Metabolites 5 and 14 showed the most active metabolites against both cancer cells, as well as they …

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The Wormholes In The Modification Of General Relativity Theory, Takol Tangphati Jan 2020

The Wormholes In The Modification Of General Relativity Theory, Takol Tangphati

Chulalongkorn University Theses and Dissertations (Chula ETD)

A traversable wormhole, which is a class of wormholes in general relativity (GR), was proposed by Morris and Thorne in 1988. However, its existence requires the exotic matter violating the energy conditions. This thesis examines the wormhole solutions in the theory of massive gravity, focusing only on the de Rham, Gabadadze and Tolley (dRGT) theory of massive gravity which is the nonlinear massive gravity without ghost and quantify the wormhole solutions. We construct the wormhole solutions in context of the modified GR, investigate their stability, and examine the conditions of the exotic matter. Two methods for wormhole constructions are applied …

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Inspection And Evaluation Of Air Filled Void Inside Reinforced Concrete Structure By Non-Destructive Testing Methods, Thanakit Klomkliew Jan 2020

Inspection And Evaluation Of Air Filled Void Inside Reinforced Concrete Structure By Non-Destructive Testing Methods, Thanakit Klomkliew

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, almost infrastructure in Thailand are almost reinforced concrete (RC) structure because they are strong and durable enough against environmental changes; nevertheless, the concrete durability will be decreased. The proper concrete integrity survey for potential remedy works is very importance, Thus, this research aims to inspect flaws especially delamination and air-filled void by four Non-Destructive Testing (NDT) methods be composed of 1) ultrasonic pulse velocity (UPV), 2) ultrasonic pulse echo (UPE), 3) impact echo (IE), and 4) ground penetrating radar (GPR). Furthermore, this research is separated two parts be consisted of idealized structures simulated defects and a realistic structure. The …

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Electrochemical Reaction For Direct Synthesis Of Amides From Aldehydes, Tanawat Rerkrachaneekorn Jan 2020

Electrochemical Reaction For Direct Synthesis Of Amides From Aldehydes, Tanawat Rerkrachaneekorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Conventional synthesis of amide involves the use of harsh condition, strong oxidizing agents, high value metal catalysts or multiple step synthesis of starting materials. To overcome these problems, in this research, we develop a mild electrochemical oxidative amidation directly from commercially available benzyl alcohols and aldehydes with amines. Optimization studies indicate that this electrochemical oxidative amidation can be proceeded via the use of sodium iodide as both electrolyte and mediator in aqueous solution performing in undivided cell at room temperature without additional additive. Under the optimized condition, we are able to perform electrochemical oxidative amidation of various benzyl alcohols and …

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Stochastic Differential Equation Models On Sphere For Animal Migration, Viput Puttanugool Jan 2020

Stochastic Differential Equation Models On Sphere For Animal Migration, Viput Puttanugool

Chulalongkorn University Theses and Dissertations (Chula ETD)

Animal migration is a seasonal movement of a bundle of animals from place to place. A migration cycle is often annually and closely linked with the cyclic pattern of seasons. A short-distance migration can be modeled on a planar surface, but most animals have long-distance migrations, e.g., Arctic terns migrate from the North Pole to the South Pole; thus, their migration should be modeled on a spherical surface. In addition, the Brownian motion term is included in a model to represent noises and randomness of movements. This work aims to simulate their migration routes using stochastic differential equations (SDEs) on …

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Effect Of Dealumination And Desilication Of Beta Zeolite On Performance Of Nickel Catalysts In Hydroisomerization For Bio-Jet Fuel Production, Warodom Hunsiri Jan 2020

Effect Of Dealumination And Desilication Of Beta Zeolite On Performance Of Nickel Catalysts In Hydroisomerization For Bio-Jet Fuel Production, Warodom Hunsiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

-The Global aviation fuel consumption tends to increase. In recent years, the European Union has announced that fossil fuels jet fuel must be mixed with 10% biofuels in 2020. bio-jet fuel production has many processes such as biomass pyrolysis. or hydro-p

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Mineral Inclusions In Sapphire From Basalt - Related Deposit In Southern Vietnam, Vu Doan Thi Anh Jan 2020

Mineral Inclusions In Sapphire From Basalt - Related Deposit In Southern Vietnam, Vu Doan Thi Anh

Chulalongkorn University Theses and Dissertations (Chula ETD)

Sapphires in Southern Vietnam have been discovered in alluvial deposit derived from Cenozoic basalts. Sample collections for this study were taken from the most significant gem fields including Pleiku, Dak Nong, Di Linh, Binh Thuan, and Krong Nang. Several syngenetic mineral inclusions in these sapphires were classified as alkali feldspar, zircon, ferrocolumbite, pyrochlore, and iron oxides. Mineral chemical characteristics of these inclusions appearred to have evolved from alkaline felsic suite. Oxide mineral inclusions occurred in sapphire included hercynite, wüstite, and ilmenite. Ilmenite ranged in composition between Il49-54He34-40Mt7-10 and Il24-30He36-38Mt35-40 falling in ilmenite-hematite series. Wüstite with nonstoichiometry, (Fe2+0.3-0.9)(Ti3+<0.179Al3+≤0.6Cr3+<0.1 Fe3+≤0.46)£≤0.23O, was usually associated with hercynite inclusion clearly indicating cogenetic sapphire formation. Wüstite and sapphire appeared to have formed from the breakdown reaction of hercynite (hercynite = sapphire+wüstite). Titanohematite series and titanomagnetite series might have crystallized during iron-titanium reequilibration via subsolidus exsolution. U-Pb geochronology of zircon inclusion in these sapphires yielded between 35.5 ± 1.6 Ma (~35 Ma) and 14.73 ± 0.29 Ma (~15 Ma) for Krong Nang sapphire, 5.94 ± 0.13 Ma (~6 Ma) for Binh Thuan and Dak Nong sapphire, and 5.491 ± 0.077 Ma (~5.5 Ma) for Di Linh sapphire. These age constraints relate to the main Cenozoic basaltic eruptions in this region. Crystallization temperature of sapphire formation was estimated at about 561- 7810C using Ti-in-zircon thermometry.

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Synthesis Of 1,2-Naphthoquinone Derivatives As Α-Glucosidase Inhibitors, Trang Pham Thi Jan 2020

Synthesis Of 1,2-Naphthoquinone Derivatives As Α-Glucosidase Inhibitors, Trang Pham Thi

Chulalongkorn University Theses and Dissertations (Chula ETD)

For a couple of decades the bioactivity of quinone has been considered as privileged structure-based drug design. In this research, 4-phenylamino, 4-alkylamino, 4-alkylphenylamino, 4-phenoxy and other derivatives of 1,2-naphthoquinone were synthesized, evaluated for their anti α-glucosidase activity and elucidated for their structure-activity relationship. The results indicated that multiple factors affecting to the α-glucosidase inhibition included π-π interaction, hydrophobic interaction and hydrogen bonding with the enzyme. In general, the main factor affecting the activity was the more favorable 1,2-dione production. The presence of electron withdrawing substituents on the phenyl ring and heteroatom linker bound to the quinone skeleton increased the activity. …

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Improved Adaptive Fractional Order Differential Method For Medical Image Enhancement, Wasin Tranghiranyathorn Jan 2020

Improved Adaptive Fractional Order Differential Method For Medical Image Enhancement, Wasin Tranghiranyathorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, we propose a construction of a new 5x5 fractional order differential mask that uses sixteen directions of gradient operator and weights each pixel in the mask by the Euclidean distance from the center of the mask. Then, we apply this new mask to the Adaptive Fractional Differential Algorithm (AFDA). The AFDA allows the optimal fractional order of each pixel to be obtained using an adaptive function constructed based on the area feature of image. Experimental results for medical images, show that the AFDA with the new mask gives better image enhancement than the original AFDA. It makes …

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Knight's Tours On Ringboards, Deficient 4 X N Chessboards And Some L-Boards, Wasupol Srichote Jan 2020

Knight's Tours On Ringboards, Deficient 4 X N Chessboards And Some L-Boards, Wasupol Srichote

Chulalongkorn University Theses and Dissertations (Chula ETD)

A (legal) knight's move is the result of moving the knight two squares horizontally or vertically on the board and then turning and moving one square in a perpendicular direction. A closed knight's tour is a sequence of knight's moves that visits every square on a given chessboard exactly once and returns to its start square. A closed knight's tour and its variations are studied widely over the rectangular chessboard or a three-dimensional rectangular box. For m,n > 2r, an (m,n,r)-ringboard or RB(m,n,r) is defined to be an m x n chessboard, denoted by CB(m x n), with the middle part …

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Sustainability Assessment Of Power Production By Chemical Looping Combustion, Watchara Uraisakul Jan 2020

Sustainability Assessment Of Power Production By Chemical Looping Combustion, Watchara Uraisakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study investigated the chemical looping combustion (CLC) process improvement for power production from energy management, system hydrodynamics, and sustainability perspectives. In the first part, the 3k factorial design was used for systematically investigating the operating variables that affect the thermal efficiency of the CLC combined with the humid air gas turbine (HAT) cycle. A set of operating variables, A) pressure of the air reactor, B) air compressor stages number, C) air compression methods, and D) air flow rate, were explored. The result showed that the highest thermal efficiency was at 55.87 % when operated at (A) 15 atm, (B) …

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Synthesis Of Sulfonamide Chalcones As Α-Glucosidase Inhibitors, I Putu Sukanadi Jan 2020

Synthesis Of Sulfonamide Chalcones As Α-Glucosidase Inhibitors, I Putu Sukanadi

Chulalongkorn University Theses and Dissertations (Chula ETD)

Diabetes mellitus occurs from deficiencies in insulin secretion or insulin resistance which leads over time to high risk for long-term macro-and microvascular complications. Diabetes mellitus type 2 contributes to more than 90% of all cases worldwide. One approach of treatment for this disorder is utilizing α-glucosidase inhibitors. Certain sulfonamides and chalcones are considered as viable candidates that are effective in reducing hyperglycemia. Forty-seven sulfonamide chalcones were synthesized by the Claisen-Schmidt reaction with various substituents on the A, B, and C-rings furnishing the desired products with 50-95 %yield. All compounds were-tested for α-glucosidase inhibitory activity. Twenty-nine compounds exhibited a very strong …

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Sexual Behaviors Of Indochinese Long-Tailed Macaque Macaca Fascicularis In Comparison With Sundaic Long-Tailed Macaque, Prangmas Kumpai Jan 2020

Sexual Behaviors Of Indochinese Long-Tailed Macaque Macaca Fascicularis In Comparison With Sundaic Long-Tailed Macaque, Prangmas Kumpai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Regarding to the previous studies reported that the past hybridization event between rhesus (Macaca mulatta; Mm) and long-tailed (M. fascicularis; Mf) macaques was occurred by the southward introgression of male Mm into Mf population, thus the Mf originating from Indochinese region carried higher level of genetic admixture of Mm ancestry than the Mf living in Sundaic region. Since it was reported that Mf are non-seasonal breeder while Mm are seasonal breeder, thus, it is interesting to compare the sexual behaviors between Indochinese and Sundaic Mf. Mf populations at Wat Haad Moon Kra Beau, Pichit province (WHM; 16° 51′N) and Khao …

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Discrete-Time Risk Model Based On Zero Inflated Poisson Time Series, Siwarak Sawongnam Jan 2020

Discrete-Time Risk Model Based On Zero Inflated Poisson Time Series, Siwarak Sawongnam

Chulalongkorn University Theses and Dissertations (Chula ETD)

An important goal of actuary is to develop models for company portfolio and insurance products. Risk measurement is one of the essential measures that inform actuaries and risk managers about the degree to which the risk bearing entity. To have precise risk measure, we require an appropriate claim count process. The common claim count processes are usually constructed from the Poisson distribution. However, insurance data have generally excess zeros which causes the overdispersion. This violates the assumption of the Poisson distribution. Therefore, alternative distributions accommodating zero count are explored in literature. The zero inflated Poisson distribution is one of the …

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Electrochemical Paper-Based Immunosensor For Biomarkers Detection, Suchanat Boonkaew Jan 2020

Electrochemical Paper-Based Immunosensor For Biomarkers Detection, Suchanat Boonkaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation focused on the development of electrochemical paper-based immunosensor for determining essential biomarkers by using a label-free immunoassay. This dissertation can be divided into four main parts. In the first part, an origami paper-based analytical device (oPAD) was developed for c-reactive protein (CRP) detection. oPAD was designed to combine the preparation of immunosensor and detection step into a single device. A gold nanoparticle modified graphene screen-printed carbon electrode (AuNPs/G/SPCE) was utilized to enhance the sensitivity of the electrode. The developed sensor was successfully applied to determine CRP in a certified serum sample. For the second part, an electrochemical paper-based …

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Effects Of Soil Composition, Surfactant Structure And Washing Conditions On Diesel Contaminated Soil Removal Efficiency Using Micellar Solution, Angkana Jantanaprasartporn Jan 2020

Effects Of Soil Composition, Surfactant Structure And Washing Conditions On Diesel Contaminated Soil Removal Efficiency Using Micellar Solution, Angkana Jantanaprasartporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Surfactant solutions are commonly used for the remediation of petroleum-contaminated soil due to their good petroleum removal performance, time-saving capability, and cost effectiveness. However, applying surfactants in excess concentrations could make oil recovery difficult. Moreover, residual surfactants in soil are toxic to microorganisms and plants. Thus, it is crucial to identify a suitable surfactant concentration for soil washing applications. The main objective of this study was to evaluate the effect of soil composition (sand, silt, clay and organic matter), surfactant structure (Tween 20, 40, 60 and 80, and Tergitol 15-S-7, 9 and 15). Subsequently, two surfactants from each series (Tween …

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Environmental Impacts And Hazardous Characteristics Of Led Lamps Waste, Delpavita Koralege Lakshani Diluka Gunawardhaa Jan 2020

Environmental Impacts And Hazardous Characteristics Of Led Lamps Waste, Delpavita Koralege Lakshani Diluka Gunawardhaa

Chulalongkorn University Theses and Dissertations (Chula ETD)

LED lighting technology has strongly taken the Thai lighting market due to the high consumption in residential, industrial and commercial sectors so the sustainability of LED lamps chain is considered as a critical factor for Thai lighting market. Additionally LED lamps waste consist of toxic metals hence improper landfilling has high potential to create negative environment and human health impact due to toxic metals contamination to environment. Therefore, this study focused on (1) quantifying environmental impact due to consumption behaviors among industrial lighting consumers and (2) hazard characterization and toxicity estimation of improper landfilling of LED lamps waste. Environmental impact …

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