Online Journal System of KMUTNB / วารสารวิชาการออนไลน์มหาวิทยาลัยเทคโนโลยีพระจอมเกล้าพระนครเหนือ
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Kinetic Study and Optimization of Tetramethylthionine Chloride Photodegradation by Iron-Perylene MOF with Hydrogen Peroxide Using Response Surface Methodology
Get PDFThis study aimed to synthesize and characterize an iron-perylene metal-organic framework (MOF) as a photocatalyst for the degradation of tetramethylthionine chloride in the presence of hydrogen peroxide. Iron-based MOF with perylene-3,4,9,10-tetra carboxylate (PTC) ligands was produced through a solvothermal technique and was characterized for its morphology, optical properties, surface area, thermal stability, and electrochemical behavior. The results showed that Fe-PTC MOF had a tubular crystalline structure with an average crystal size of 51 nm, a bandgap energy of 1.94 eV, and was responsive to visible light. Thermal analysis revealed a significant weight loss of 63.53% between 390 °C and 490 °C due to the decomposition of the organic linker, with an exothermic heat release of 5.97 J/mg. Electrochemical characterization showed an onset oxidation potential of 0.641 V (vs. Standard Hydrogen Electrode (NHE)) and a calculated Lowest Unoccupied Molecular Orbital (LUMO) energy level of –1.299 V, indicating potential applications in photocatalytic and photovoltaic technologies. Photocatalytic activity tests demonstrated that the degradation of tetramethylthionine chloride followed pseudo-first-order kinetics, and optimization using Response Surface Methodology (RSM) identified the optimal conditions for degradation: 1.5 mg of photocatalyst, 0.2 M H2O2 concentration, and 133 min of contact time. These results underscore the effectiveness of Fe-PTC MOF in treating dye-contaminated textile wastewater under illumination with visible light
Comparative Study on Techno-Economic Analysis for Various Organosolv Fractionation of Bagasse in Thailand
Get PDFProcess simulation is a crucial tool for conducting techno-economic analyses of biomass fractionation processes, providing insights into technical and economic aspects to optimize efficiency, reduce costs, and enhance the viability of production. This study focuses on the development and comparison of three scenarios based on organosolv fractionation methods. The mass balance analysis revealed significant differences in product yields, with scenario 2 achieving the highest cellulose (7,240.23 kg/day) and lignin (900.13 kg/day) outputs, scenario 3 showing a balanced profile with high hemicellulose recovery (2,959.81 kg/day), and Scenario 1 offering moderate outputs for cellulose and lignin. Economic evaluation indicated that scenario 3 was the most cost-efficient, driven by reduced operating costs, while scenario 1 had the highest total capital and operating expenses. Sensitivity analysis demonstrated minimal variability across scenarios but highlighted the need to study product pricing and future returns. Toxicity evaluation identified scenarios 1 and 3 as safer options due to the lower hazard classification of chemicals used compared to scenario 2. Overall, Scenario 3 emerged as the most favorable for cost-efficient and safe production of cellulose and lignin, supporting its potential for industrial-scale applications
Cavalcade Legume (Centrosema pascuorum) Used as Soil Amendment in RD41 Rice Fields: Short-term Effects on the Soil Nematode Community, Soil Properties, and Yield Components
Get PDFNumerous phytoparasitic nematodes have been identified in Thailand’s paddy fields, which routinely cause substantial reductions in rice crop yields. However, effective strategies for their management have yet to be documented. In this study, cavalcade legume was used as a soil amendment in RD41 rice fields to examine its effects on the soil nematode community, soil properties, and yield components compared to untreated control plots. The results demonstrated that the population densities of plant-parasitic nematodes (PPNs) in the order Tylenchida, primarily Hirschmanniella sp., significantly decreased in cavalcade-treated plots across all soil sampling periods. Moreover, there was an increase in the populations of beneficial nematodes within the orders Dorylaimida and Araeolaimida. In contrast, greater PPN populations were observed in the control plots compared to the initial nematode population. In addition to reducing PPN populations, this legume showed other benefits, specifically increased soil properties (available P) and rice plant growth (plant height and number of tillers). While there was no statistically significant difference in soil organic matter (SOM) content, the application of this legume tended to increase SOM content, in contrast to a decrease in SOM content observed in the control plots. Overall, this study provides valuable insights into the substantial advantages of using cavalcade legumes in RD41 rice fields
Gelatin Gel from By-products of Sand Jellyfish (Rhopilema hispidum): Physicochemical and Biochemical Characterization
Get PDFSalted sand-type jellyfish by-products are abundant in collagen, which may be processed into gelatin to decrease food waste. From the production standpoint, various factors affect gel qualities, including raw material used, pretreatment methods, and extraction times. So far, gelatin extracted from desalted sand-type jellyfish by-products (D-SJB) must be adequately characterized. Therefore, this research aimed to characterize gelatin from D-SJB using different pretreatment methods and extraction times. D-SJB was treated with 0.2 M hydrochloric acid (acid method) and extracted for 24 h at 60 °C (SA24), the optimal gelatin extraction condition with the highest gel qualities, while the jellyfish gelatin obtained after D-SJB was treated with pepsin and extracted for 48 h had the lowest gel qualities. The viscosity, gel strength, gelling temperature, and melting temperatures of SA24 were 20.80 cP, 352.22 g, 11.97 °C, and 22.70 °C, respectively. All jellyfish gelatin’s gelling and melting temperatures ranged from 6.13−11.97 °C and 15.85−22.70 °C, exhibiting a cold set gel and unstable gels at room temperature. The different pretreatment methods and extraction times during the jellyfish gelatin production resulted in the conversion of amides A, B, I, II, and III, especially the wavenumber of the amide I increased after pepsin pretreatment and increased with longer extraction time. Twenty-one collagen subtypes in bovine, fish, and jellyfish gelatin were analyzed using LC-MS/MS. The collagen alpha-2(I) chain, a key gelatin component, was identified in all gelatins. The research novelty showed the profound characterization results of gelatin gel produced from D-SJB. However, further experiments will be needed for pilot-scale production to be used in food and non-food applications
Two-Step Reaction for Biodiesel Synthesized from a High-Free Fatty Acid Crude Palm Kernel Oil
Get PDFBiodiesel was synthesized through a two-step reaction using crude palm kernel oil with high-free fatty acids (FFAs) and methanol. The two-step reaction involves esterification and transesterification. Esterification was carried out with a variation of H2SO4 (10%, 15%, and 20% w/v) at 65 °C for 120 min. Esterification produced fatty acid methyl ester (FAME) with an ester content of 67.56%. FAME was used as feedstock for transesterification. Transesterification was carried out with variations in reaction time (120, 180, and 240 min) at 65 °C in addition to NaOH 0.5% (w/w). Transesterification produced biodiesel, glycerol, and soap (side product). Biodiesel was separated using decantation and washing with warm distilled water at 40 °C. The optimum biodiesel was obtained at 180 min with 96.59% ester content. The characteristics of the optimum biodiesel were an FFAs of 0.2 mg KOH/g, iodine value of 20.12 g I2/100 g, density of 0.86 g/mL, kinematic viscosity of 2.51 mm2/s water content of 0.031%, ash content of 0.02%, cetane number of 60.8, flash point of 120 °C. Biodiesel has strong band spectra for C-H on 2,922.70 cm–1, C=O on 1,739.38 cm–1, C-H2 on 1,460.25 cm–1, C-O on 1,197.29 cm–1, and O-H on 3,425.10 cm–1. In conclusion, a two-step reaction is an effective method to synthesize biodiesel using CPKO with high FFAs as feedstock
Carica papaya-Derived Carbon Nanodots for the Detection of Fe (III) Ions
Get PDFCarbon dots (CDs) possess distinctive optical and electronic properties as well as dimensions smaller than 10 nm, making them a unique category of carbon-based nanomaterials. They have been widely utilized across various domains including sensors, photocatalysis, biomedicine, and optoelectronics. This study investigates the use of a one-step hydrothermal synthetic approach to produce nanocarbon dots derived from Carica papaya seeds. Through the application of sophisticated characterization methods, the structural properties of the carbon nanoparticles were verified. These techniques included UV-visible absorption spectroscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and high-resolution transmission electron microscopy (HR-TEM). The photoluminescence emission of carbon dots (CDs) has been found to depend on excitation, as determined by photoluminescence (PL) spectroscopy. This study has explored the interaction between various metal ions and the photoluminescent properties of CDs, revealing a particularly noteworthy interaction with Fe (III) ions. The Stern-Volmer equation is utilized to examine the extinction mechanism linked with the sensing capability of carbon dots, resulting in the establishment of a recognition threshold of 0.36 μM. The existence of surface functional groups, which enable the formation of complexes with Fe (III) ions is a primary factor contributing to the sensing capabilities observed. This paper explores the fabrication and advancement of environmentally friendly sensor systems for detecting metal ions in biomedical and environmental contexts
เทคนิคการสำรวจด้วยภาพถ่ายระยะใกล้สำหรับงานสถาปัตยกรรมไทย กรณีศึกษา มณฑปพระพุทธสิหิงค์ มหาวิทยาลัยเทคโนโลยีราชมงคลกรุงเทพThe Close Range Photogrammetry Technique for Thai-architecture: A Case Study Sihing Buddha Statue Mandapa at RMUTK
No full textจากปัญหาการสร้างแบบจำลองสามมิติด้วยเทคนิคการสำรวจด้วยภาพถ่ายระยะใกล้เชิงเลขของสถาปัตยกรรมไทยที่มีรายละเอียดซับซ้อนไม่สามารถใช้เพียงอุปกรณ์ชนิดใดชนิดหนึ่งได้เนื่องจากเซนเซอร์แต่ละชนิดให้มุมมองและความละเอียดที่แตกต่างกันเพื่อปรับปรุงคุณภาพของแบบจำลองสามมิติให้สมบูรณ์ยิ่งขึ้น งานวิจัยนี้มีวัตถุประสงค์ในการศึกษาเทคนิคการสำรวจด้วยภาพถ่ายระยะใกล้เชิงเลขเพื่อการบูรณาการข้อมูลภาพถ่ายจากเซนเซอร์ 3 ประเภท ประกอบด้วย 1) ภาพถ่ายจาก DJI Mavic 3 Classic โดยการบินวนเป็นวงกลมรอบมณฑป (POI) ที่ระดับความสูงที่ต่างกัน 6 ระดับ 2) บันทึกข้อมูลภาพถ่ายด้วย Canon DSLR เลนส์คงที่ 20 มม. ภายในพื้นที่ส่วนพระพุทธสิหิงค์และรายละเอียดภายในมณฑป และ 3) บันทึกข้อมูลภาพถ่ายด้วยสมาร์ทโฟนในส่วนของรายละเอียดบันได การประมวลผลบล็อกลำแสงของภาพถ่ายทั้งหมด แบ่งจากเซนเซอร์ 3 ประเภท เป็น 4 บล็อกลำแสง การบูรณาการเพื่อประมวลผลบล็อกลำแสงภาพถ่ายร่วมกันด้วยเงื่อนไขการกำหนดจุดรังวัดร่วม และจุดควบคุมภาพถ่าย โดยปัจจัยการกระจายตัวของจุดรังวัดร่วมมีผลต่อการทับซ้อนและการเรียงตัวของบล็อกลำแสง ผลลัพธ์การสร้างแบบจำลองสามมิติของมณฑปพระพุทธสิหิงค์ที่สร้างมีสีพื้นผิว รูปร่าง ตำแหน่งของวัตถุ มีความแม่นยำและรายละเอียดสมบูรณ์ แสดงให้เห็นว่าการบูรณาการเซนเซอร์สามารถปรับปรุงข้อจำกัดของการใช้เซนเซอร์เพียง 1 ชนิดซึ่งเหมาะสมสำหรับงานทางสถาปัตยกรรมไทยThe challenge of generating three-dimensional models using digital close range photogrammetry technique in Thai architecture, characterized by intricate features, necessitates the usage of many equipment types, as each sensor offers distinct perspectives and resolutions. To enhance the comprehensiveness of the 3D model, the aim of this research was to investigate a digital close range photogrammetry method for amalgamating photographic data from three sensor types: 1) images captured by the DJI Mavic 3 Classic while orbiting the point of interest at six distinct altitudes; 2) photographic data recorded with a Canon DSLR equipped with a 20 mm fixed lens within the Buddha Sihing area and the mandap's interior; and 3) photographic data obtained with a smartphone focusing on the staircase details. Processing of all photographic bundle blocks segmented into four bundle blocks from three types of sensors. The system integrated photo bundle blocks and sets parameters for identifying manual tie points and photo control points. The distribution factor of the manual tie points influenced the overlap and alignment of bundle blocks. The outcomes of the three-dimensional modelling of the Buddha Sihing mandap encompassed a comprehensive and precise representation of color, texture, shape, and spatial positioning of things. It demonstrated that sensor integration could enhance the constraints associated with utilizing a singular sensor type, making it appropriate for Thai architectural applications
A Lesson Learned from the UK Rail Project: An Analysis of Critical Success Factors (CSFs) through the Project Life Cycle (PLC)
Get PDFThis study examines the critical success factors (CSFs) of railway construction projects through the lens of the Project Life Cycle (PLC), addressing the defining, planning, implementing, and closing phases. Although CSFs have been widely studied, their systematic application to Thailand’s railway sector remains limited, particularly in linking lessons from international best practices. Employing a systematic literature review and content analysis, the research synthesizes evidence from major United Kingdom projects, including Crossrail and High Speed 2 (HS2), and compares them with experiences in Thailand. The analysis identifies governance, stakeholder collaboration, and risk management as decisive CSFs across all PLC phases. Key findings highlight that early participatory consultations enhance legitimacy, structured risk registers and stakeholder mapping strengthen planning, while real-time monitoring and independent audits improve implementation oversight. In the closing phase, structured handovers and training programs are vital for operational continuity. By integrating international lessons with a PLC perspective, this study provides policymakers and practitioners with a structured framework for improving the governance, efficiency, and sustainability of Thai railway projects. Beyond this sectoral focus, the PLC–CSFs framework demonstrates wider applicability to large-scale infrastructure initiatives, contributing to both theoretical advancement and practical guidance for sustainable transport development in Thailand
Pickering Emulsions of Kaffir Lime Oil Stabilized by Modified Tapioca Starch: Impact of Particle Size Reduction Methods and Octenyl Succinic Anhydride Grafting
Get PDFThe main challenges in using tapioca starch for pickering emulsions are its native micron-sized particles, which are too large to stabilize small oil droplets, and its highly hydrophilic nature, which limits its ability to balance oil-water interfaces. This study explores the modification of tapioca starch to encapsulate kaffir lime oil (KO) in pickering emulsions, emphasizing particle size reduction and surface functionalization. Methods included enzymatic hydrolysis (alpha-amylase, alpha-amylase with glucoamylase, and pullulanase), sulfuric acid hydrolysis, and ethanol precipitation. Ethanol precipitation emerged as the most effective, producing ultra-fine particles (96–150 nm) with superior emulsion stability. Surface analysis revealed that enzymatic treatments affected particle morphology, while ethanol precipitation formed the smallest, smoothest particles and the lowest crystallinity (8.4%), compared to sulfuric acid hydrolysis, which showed the highest crystallinity (37.7%). Surface functionalization with octenyl succinic anhydride (OSA) enhanced starch hydrophobicity, confirmed by Fourier-transform infrared (FT-IR) spectroscopy and increased water contact angles. Pickering emulsions prepared with ethanol-precipitated starch esterified with 5% OSA showed the highest stability. Incorporating medium-chain triglyceride (MCT) oil at a KO/MCT ratio of 0.4/0.8 further improved droplet size and emulsion stability. These findings highlight ethanol-precipitated and OSA-modified tapioca starch as an effective bio-surfactant for stabilizing Pickering emulsions, with potential for sustainable and high-value industrial applications
Genetic Diversity of Hemp Germplasm in Northern Thailand
Get PDFCannabis sativa L., commonly known as hemp, is a plant native to Central Asia. It is well known for its cannabinoid compounds, which have significant potential for medical applications. Recognizing the economic and medical value of hemp, the Thai government has permitted its cultivation for commercial, medical, and research purposes. However, a comprehensive understanding of hemp genetics is crucial to support industry expansion and enhance future breeding programs. This study investigated the genetic diversity of 37 hemp accessions collected in northern Thailand, along with two reference varieties (RPF1 and RPF2). Using DArTSeq-based genotyping-by-sequencing and whole-genome sequencing technologies, we identified 3,609 single nucleotide polymorphisms (SNPs). STRUCTURE analysis, principal component analysis (PCA), and neighbor-joining analysis consistently identified three genetic clusters; however, these clusters did not correlate with geographical locations. Genetic differentiation among clusters was observed (fixation index, FST = 0.064-0.079; Nei’s coefficient of genetic differentiation, Nei’s GST = 0.058-0.078). Total genetic diversity estimated (expected heterozygosity, HE = 0.348; observed heterozygosity, HO = 0.092). Global inbreeding (FIT = 0.033) and molecular variance (4.83%) suggested low to moderate genetic differentiation, while the high inbreeding coefficient (FIS = 0.737) indicated substantial inbreeding within clusters. The genetic data from this study provide a resource for developing molecular markers to distinguish hemp varieties, supporting selective breeding efforts. These findings will contribute to improving agronomic traits, conserving genetic diversity, and ensuring the sustainable use of hemp genetic resources