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2020

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Articles 14611 - 14640 of 14752

Full-Text Articles in Physical Sciences and Mathematics

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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Pvdf Hollow Fiber Membrane Modification For Dye Wastewater Treatment By Ozonation Membrane Contacting Process, Hanh Le Thi My Jan 2020

Pvdf Hollow Fiber Membrane Modification For Dye Wastewater Treatment By Ozonation Membrane Contacting Process, Hanh Le Thi My

Chulalongkorn University Theses and Dissertations (Chula ETD)

One of the main pollutions from textile wastewater is the dyeing wastewater containing color and organic matters. Among the treatment methods of dye wastewater, ozonation membrane contactor was used as the concept of this research. PVDF membranes were developed by pulse inductively coupled plasma (PICP) and grafted by organosilanes for hydrophobicity enhancement applied for dye wastewater treatment by ozonation membrane contactor. To obtain a stable grafting, the surface of PVDF hollow fiber membrane was activated by the plasma operating condition including two different plasma gases (oxygen and argon), applied voltage and pressure, plasma treatment shot, followed by grafting with four …

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Assessing Environmental Impact Through Dpsir Framework And Environmental Justice Lenses:A Case Study Of Inland Capture Fisheries In Mahakam River, Etik Sulistiowati Ningsih Jan 2020

Assessing Environmental Impact Through Dpsir Framework And Environmental Justice Lenses:A Case Study Of Inland Capture Fisheries In Mahakam River, Etik Sulistiowati Ningsih

Chulalongkorn University Theses and Dissertations (Chula ETD)

Inland capture fisheries significantly contribute to the achievement of SDG, but most inland capture fisheries are poorly managed or not managed at all. Inland fishery is often facing against the big-scale industrial project. In the Middle Mahakam Area, two dominant natural resources exploited for the industrial project are palm oil and coal mining. Palm oil production, coal mining production, the human population was increasing in the last ten years, and on the opposite, the water quality index is decreasing. However, although many previous studies suggested that fish catches are declining, fisheries statistics show the opposite data. Government statistics show that …

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Development Of X-Ray Shielding Material From Combination Of Amorphous Cellulose Of Used Paper, Barium Sulphate, And Natural Rubber, Harinate Mungpayaban Jan 2020

Development Of X-Ray Shielding Material From Combination Of Amorphous Cellulose Of Used Paper, Barium Sulphate, And Natural Rubber, Harinate Mungpayaban

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aimed to fabricate X-ray shielding substrates using amorphous cellulose from office waste paper and eucalyptus pulp mixed with natural rubber to produce the prototypes. The amorphous cellulose was prepared using only the sulfuric acid at 0 °C to rearrange the crystalline chain to the amorphous chain. After that, the barium sulfate/amorphous cellulose composite (Ba/AC) was regenerated using barium chloride solution. The shielding sheets were formulated by mixing vulcanization natural rubber individual with Ba/AC from office waste paper (NR-W), the purified eucalyptus pulp (NR-E), and barium sulfate powder (NR-P). The NR-W and NR-E were shown the predominant attenuation than …

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Prediction Of Arsenic Contamination In Rayong Groundwater Basin Using Machine Learning Based Approaches, Narongpon Sumdang Jan 2020

Prediction Of Arsenic Contamination In Rayong Groundwater Basin Using Machine Learning Based Approaches, Narongpon Sumdang

Chulalongkorn University Theses and Dissertations (Chula ETD)

The present study used three algorithms consisting of Support Vector Machine (SVM), Random Forest (RF), and Artificial Neuron Network (ANN) to locate risk area of arsenic (As)contamination in Rayong coastal aquifers, Thailand. There were three parts in this study consisting of 1) selecting the proper parameters 2) selecting the appropriate model, and 3) constructing the risk map of As. To perform models efficiently, the parameters used to generate the models have to be selected based on the correlation of each hydrochemical parameter with As concentration, which could explain the mechanisms of As release in groundwater. Due to major parameters in …

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Synthesis Of Nanoscale Zerovalent Iron (Nzvi) Derived From Lignin Containing Wastewater For Arsenic Removal, Phoomipat Jungcharoen Jan 2020

Synthesis Of Nanoscale Zerovalent Iron (Nzvi) Derived From Lignin Containing Wastewater For Arsenic Removal, Phoomipat Jungcharoen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nanoscale zerovalent iron (nZVI) plays a significant role in environmental remediation including the removal of arsenic from groundwater and drinking water. This study synthesized modified nZVI particles in order to remove arsenic in drinking water. Reductive precipitation under various conditions was used to produce non-modified nZVI (B-nZVI) and lignin-modified nZVI using either 1 g/L lignin solution (L-nZVI) or pulp and paper wastewater (P-nZVI) as the substrate. Ferrous to borohydride molar ratio of 1:1 was found to be the most appropriate ratio for L-nZVI and P-nZVI production since lignin was incorporated into the nZVI structure the most. According to TEM analysis, …

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Fishermen's Participation In Marine Litter Collection Schemes In Thailand, Phornphavit Thongphaijit Jan 2020

Fishermen's Participation In Marine Litter Collection Schemes In Thailand, Phornphavit Thongphaijit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Marine litter is a global environmental problem that poses various threats to the environment, the economy and society. Its impacts, for example, are the cost of beach cleaning, tourism, the beautiful landscape and etc. Marine litter, which later breaks into microplastics, affects marine lives contributing to the loss of economy to the people who depend on them. Several measures are used to tackle marine litter, including prevention and reduction of waste generation, prevention and reduction of litter reaching the marine environment, and marine litter removal. The latter is essential to clean already-at-sea litter or marine debris. Thailand, among the top …

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Perspectives And Challenges Of Green Hotel In Thailand, Pornwajee Sangmanee Jan 2020

Perspectives And Challenges Of Green Hotel In Thailand, Pornwajee Sangmanee

Chulalongkorn University Theses and Dissertations (Chula ETD)

The hotel business is intense resource consumption such as water, energy, and non-durable products to delight customers, leading to environmental problems. With this regard, the transformation of the green hotel and environmental saving programs can dwindle the hotel property's adverse impacts. The purposes of this paper are 1) to study the perception of hotel practitioners and stakeholders toward the critical challenges of green hotel transformation and 2) to propose the recommendations for green hotel operations and certification scheme in Thailand. The study employed mixed methods to collect the data. The in-depth interviews were along with field observation; the interviews data …

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City-Wide Greenhouse Gas Mitigation Options To Support Global Climate Goals: Case Studies Of Bangkok, Chiang Mai, And Rayong, Thailand, Sittisak Sugsaisakon Jan 2020

City-Wide Greenhouse Gas Mitigation Options To Support Global Climate Goals: Case Studies Of Bangkok, Chiang Mai, And Rayong, Thailand, Sittisak Sugsaisakon

Chulalongkorn University Theses and Dissertations (Chula ETD)

The action of city on climate mitigation becomes a crucial role. The aims of this study were to quantify greenhouse gases (GHGs) emission, identify feasibility of mitigation options in selected provinces, and to evaluate the performance of local capacity to support Thailand's Nationally Determined Contributed (NDC) and 1.5oC limit pathway. Three provinces, including Bangkok, Chiang Mai and Rayong of Thailand were selected as case studies. The results revealed that stationary energy was the greatest contribution to the city's GHGs emissions in all case studies. Transportation was the second largest emitter in Bangkok and Chiang Mai, whereas IPPU was the second …

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Leaching Potential Assessment Of Atrazine And Nitrate In Sugarcane Field, Suphan Buri Province, Sorranat Ratchawang Jan 2020

Leaching Potential Assessment Of Atrazine And Nitrate In Sugarcane Field, Suphan Buri Province, Sorranat Ratchawang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Atrazine is widely used as a herbicide to control annual broadleaf in agricultural area such as rice and sugarcane. It is considered as one of endocrine disrupting chemicals. Atrazine also affects liver, the central nervous system, immune system and cardiovascular function. The study area is sugarcane field in U-thong and Song Phi Nong district, Suphan Buri province. In this area, soil and groundwater samples were collected at eight different points distributed over the sugarcane area with different soil types. Batch adsorption experiment was carried out to evaluate the proper adsorption isotherm of each soil. Additionally, groundwater samples were analyzed for …

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Detection Of Arsenite-Oxidizing Bacteria In Groundwater From A Gold Mine Under Different Geochemical Environments, Supeerapat Kraidech Jan 2020

Detection Of Arsenite-Oxidizing Bacteria In Groundwater From A Gold Mine Under Different Geochemical Environments, Supeerapat Kraidech

Chulalongkorn University Theses and Dissertations (Chula ETD)

Millions of people around the world potentially expose to arsenic (As) contaminated groundwater. Besides, the dominant form of As in groundwater is arsenite (As+3) and is more toxic than arsenate (As+5). This study integrated the microbial investigation, geochemical modeling, and multivariate statistical analysis to investigate the arsenite-oxidizing bacteria community from As-contaminated groundwater and its environmental influencing factors in order to understand and further develop the in-situ arsenic bioremediation technology. Microbial investigation was focusing on the detection and identification of native arsenite-oxidizing bacterial community using PCR-DGGE, cloning and sequencing of arsenite oxidase (aoxB) gene amplicons. Nine groundwater samples were collected from …

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Sustainable Business Development Through Sufficiency Economy Practice : A Case Study Of Thai Listed Companies, Veerawin Korphaibool Jan 2020

Sustainable Business Development Through Sufficiency Economy Practice : A Case Study Of Thai Listed Companies, Veerawin Korphaibool

Chulalongkorn University Theses and Dissertations (Chula ETD)

The purpose of the research is to determine the sufficiency economy philosophy (SEP) performance through annual and sustainable development reports and simplify the outcomes by representing through a scoring system. Each of the SEP elements was aligned with each GRI sub-topic to generate a SEP scoring system. Then, the results from the scoring system were verified by testing the relationship between SEP performance and firm-specific risk of 34 Thai listed companies from 2013 to 2018 via panel data analysis. The global reporting initiative (GRI) standards were used as the fundamental scoring system as it's widely used and accepted in academic …

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Assessments Of Hydraulic Responses To Climate Variability Of Dominant Trees In Successional Forests In Khao Yai National Park For Environmental Management, Weerapong Unawong Jan 2020

Assessments Of Hydraulic Responses To Climate Variability Of Dominant Trees In Successional Forests In Khao Yai National Park For Environmental Management, Weerapong Unawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

In Southeast Asia, tropical forests have been increasingly threatened by human disturbances and climate change-induced water stress. However, uncertainty remains as to how these forests would respond to environmental changes under water deficit conditions. Here, we conducted a study of seasonal variation in leaf water status and hydraulic properties of dominant tree species across forest successional stages in Khao Yai National Park, Thailand. Specifically, we measured midday leaf water potential (Ψmd) during the wet and dry season, and assessed branch xylem vulnerability at which 50% is lost (P50). The associations between P50 and maximum xylem hydraulic conductivity (Ksmax) and maximum …

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Surface-Enhanced Raman Scattering Using Fluorescence-Quenched Carbon Quantum Dots For Mercury Ion Detection, Andaru Dena Prasiwi Jan 2020

Surface-Enhanced Raman Scattering Using Fluorescence-Quenched Carbon Quantum Dots For Mercury Ion Detection, Andaru Dena Prasiwi

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mercury ion (Hg2+) is one of the most challenging problems due to its high toxicity at low concentration and bioaccumulative effects affecting human health. Herein, we propose a strategy to exploit the fluorescence quenching of carbon quantum dots (CQDs) combined with surface-enhanced Raman scattering (SERS) technique to detect Hg2+. CQDs exhibit strong fluorescence emission interfering SERS measurement. However, with the presence of Hg2+, fluorescence from CQDs can be quenched, and the SERS spectrum can be collected. In this work, SERS spectra of rhodamine 6G (R6G) incorporated with CQDs and Hg2+ (0.100‒100 ng/L) were studied. The SERS spectra of R6G was …

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Paper-Based Device For Urinary Oxalate Detection, Kanphitcha Mueangdech Jan 2020

Paper-Based Device For Urinary Oxalate Detection, Kanphitcha Mueangdech

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, a simple method for urinary oxalate determination was developed using testing paper modified with reddish-brown Fe(III)-curcumin complex. Oxalate in sample interacted with Fe(III) ions on the surface of the testing paper to form a Fe(III)-oxalate complex in solution, resulting in a decrease of the amount of Fe(III)-curcumin complex on the paper surface. The amount of the remaining Fe(III)-curcumin complex on the testing paper was inversely proportional to the oxalate level in the sample solution. A change of the testing paper color from reddish-brown to yellow could be observed and the color intensity was determined by ImageJ program. …

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Synthesis Of Nitrogen-Doped Carbon Dots From Aromatic Amino Acids, Nattapon Siengdung Jan 2020

Synthesis Of Nitrogen-Doped Carbon Dots From Aromatic Amino Acids, Nattapon Siengdung

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nitrogen-doped carbon dots (NCDs) were synthesized from amino acids via the hydrothermal method under an acidic condition. L-histidine, L-phenylalanine, L-tyrosine, L-tryptophan, and glycine were used as a precursor which NCDs synthesized from those precursors were labeled as His-NCDs, Phe-NCDs, Tyr-NCDs, Trp-NCDs, and Gly-NCDs, respectively. Spectroscopic and microscopic characterizations were operated to investigate optical properties, chemical structures, and morphologies of NCDs. The results show that all NCDs show a spherical shape with an average diameter of 4.11±1.20 nm. Their energy gap between the highest occupied molecular orbitals (HOMO) and the lowest unoccupied molecular orbitals (LUMO) obtained from fluorescence spectroscopy can be …

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Development Of Paper-Based Analytical Devices For Simultaneous Naked-Eye Detection Of Heavy Metal Ions, Pornphimon Kamnoet Jan 2020

Development Of Paper-Based Analytical Devices For Simultaneous Naked-Eye Detection Of Heavy Metal Ions, Pornphimon Kamnoet

Chulalongkorn University Theses and Dissertations (Chula ETD)

Paper-based analytical device was fabricated by a polymer screen printing and wax printing methods. The various types of device were designed for simultaneous heavy metal ions detection in synthetic unknown and real water samples. The colorimetric method was applied to detect the heavy metal ions using 1-(2-pyridylazo)-2-naphthol, bathophenanthroline, 1, 5-diphenylcarbazide, bathocuproine, dimethylglyoxime, dithizone, and 4-(2-pyridylazo) resorcinol as complexing agents. However, complexing agents require very highly selectivity. To improve the selectivity for heavy metal ion detection, a device was designed with pretreatment zones and the masking agents were applied to remove interfering ions. The proposed method was successfully applied for simultaneous …

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Effects Of Microplastic On Water Flow And Contaminant Transport In Water-Saturated Sand, Siravit Chanprasit Jan 2020

Effects Of Microplastic On Water Flow And Contaminant Transport In Water-Saturated Sand, Siravit Chanprasit

Chulalongkorn University Theses and Dissertations (Chula ETD)

After decades of discovery of microplastic contamination over the world, effects of microplastic on organisms have been studied thoroughly, whereas ones on hydrological aspect are yet quite mentioned. As one of major microplastic sinks, soils are inevitable to face a number of microplastics; however, the movement of microplastic through soil and its consequence are still unknown. Then this research would be focusing on effects of microplastic contamination in soil sediment on hydraulic and transport parameters. Hydraulic conductivity (K), distribution coefficient (Kd), and dispersion coefficient (D) are the main parameters to be measured. The column experiment in column of diameter 7 …

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การย้อมสีอินดิโกบนเส้นด้ายฝ้ายโดยใช้สารละลายหลังการลอกแป้งด้วยอะไมเลสและการฟอกสีผ้าเดนิมด้วยเซลลูเลส, จิตาภัค ชูดวง Jan 2020

การย้อมสีอินดิโกบนเส้นด้ายฝ้ายโดยใช้สารละลายหลังการลอกแป้งด้วยอะไมเลสและการฟอกสีผ้าเดนิมด้วยเซลลูเลส, จิตาภัค ชูดวง

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้ทดลองนำน้ำเสียจากการลอกแป้งผ้าเดนิมดิบด้วยเอนไซม์อะไมเลสร่วมกับเอนไซม์กลูโคอะไมเลส (น้ำเสียมีกลูโคส) และการนำน้ำเสียจากการฟอกสีผ้าเดนิมด้วยเอนไซม์เซลลูเลส (น้ำเสียมีสีอินดิโก) มาใช้ในการรีดิวซ์และย้อมสีอินดิโกลงบนเส้นด้ายฝ้าย โดยเริ่มแรกผ้าเดนิมดิบจะผ่านการลอกแป้งด้วยเอนไซม์อะไมเลสร่วมกับเอนไซม์กลูโคอะไมเลส น้ำเสียจากการลอกแป้งถูกวิเคราะห์หาความเข้มข้นของกลูโคสในน้ำเสีย หลังจากนั้นผ้าเดนิมที่ผ่านการลอกแป้งแล้วจะถูกนำมาฟอกสีด้วยเอนไซม์เซลลูเลสร่วมกับหินกรวด น้ำเสียจากการฟอกสีถูกนำมาวิเคราะห์ค่าความเข้มข้นของสีอินดิโกในน้ำเสีย รีดิวซ์สีในน้ำเสียจากการฟอกสีโดยใช้โซเดียมไดไทโอไนต์ กลูโคส และน้ำเสียจากการลอกแป้ง (น้ำเสียมีกลูโคส) จากนั้นน้ำเสียจากการฟอกสีที่ถูกรีดิวซ์จะถูกนำไปย้อมเส้นด้ายฝ้าย เส้นด้ายย้อมสีถูกวิเคราะห์หาค่าความเข้มสีและเฉดสี และร้อยละของการผนึกสีบนเส้นด้าย ผลการวิจัยพบว่า เส้นด้ายฝ้ายย้อมด้วยสีที่ถูกรีดิวซ์โดยโซเดียมไดไทโอไนต์และกลูโคส (ณ ภาวะที่ทำให้สารละลายสีย้อมมีค่าความต่างศักย์ออกซิเดชันและรีดักชัน (โออาร์พี) ที่เหมาะสม คือ มีค่า -600 ถึง -700 mV) มีเฉดสีน้ำเงินโดยมีค่าความเข้มสี 1.41 และ 0.74 และการผนึกสีบนเส้นด้าย 74.8% และ 73.8% ตามลำดับ โดยเส้นด้ายย้อมด้วยสีที่ถูกรีดิวซ์ด้วยโซเดียมไดไทโอไนต์มีสีน้ำเงินที่เข้มกว่าเส้นด้ายย้อมด้วยสีที่ถูกรีดิวซ์ด้วยกลูโคสประมาณ 1 เท่า แต่ต่างมีการผนึกสีใกล้เคียงกัน (74-75%) ในขณะที่การศึกษาเบื้องต้นของการใช้น้ำเสียจากการลอกแป้ง (น้ำเสียมีกลูโคส) เป็นสารรีดิวซ์สีในน้ำเสียจากการฟอกสี (แทนการใช้โซเดียมไดไทโอไนต์และการใช้กลูโคสเป็นสารรีดิวซ์สี) เส้นด้ายหลังย้อมมีเฉดสีน้ำเงินอ่อนมาก เนื่องจากค่าโออาร์พีของสารละลายสีมีค่าสูงเกินไป อย่างไรก็ตาม งานวิจัยนี้พบว่า สามารถนำน้ำเสียจากการลอกแป้งและน้ำเสียจากการฟอกสีมาหมุนเวียนใช้เป็นวัตถุดิบในการย้อมสีเส้นด้ายฝ้าย แต่ยังต้องปรับปรุงกระบวนการลอกแป้งให้น้ำเสียจากการลอกแป้งมีกลูโคสเกิดจากการลอกแป้งมากขึ้น อาจด้วยการเพิ่มความเข้มข้นของเอนไซม์กลูโคอะไมเลสที่ใช้ในการลอกแป้ง หรือเติมกลูโคสเพิ่มลงไปในน้ำเสียจากการลอกแป้ง เพื่อลดค่าความต่างศักย์ออกซิเดชันและรีดักชันจนถึงค่าที่เหมาะสม คือ ต่ำกว่า -600 mV ลงไป จะทำให้สามารถนำน้ำเสียจากทั้งสองส่วนของการผลิตผ้าเดนิม (น้ำเสียจากการลอกแป้งและจากการฟอกสีผ้าเดนิม) มาหมุนเวียนใช้ต่อได้อย่างสมบูรณ์แบบ

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Remediation Of Cadmium Contaminated Soil By Corn Plantation With Biosurfactants Amendment, Pannawee Mekwichai Jan 2020

Remediation Of Cadmium Contaminated Soil By Corn Plantation With Biosurfactants Amendment, Pannawee Mekwichai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Phytoremediation by a local economic crop (corn) is proposed as an alternative treatment option that allows simultaneous cadmium (Cd) contamination reduction and corn biomass utilization in Mae Sot District Tak Province. Biosurfactants, rhamnolipid (RL) and saponin (SP), were introduced to enhance Cd phytoextraction. The optimum RL and SP dose was 4 mmol kg−1 which was applied in Cd soil concentration of 36.8 mg kg-1. Cd uptake and corn biomass were higher with biosurfactant addition than in the control (without biosurfactants addition), by 4.7 and 2.3-folds, respectively, on the 30th day of corn plantation. The optimum biosurfactant doses were applied to …

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