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The effects of inulin and polydextrose fortifications on physicochemical properties, probiotic viability and sensory acceptability of coconut milk set yoghurt analogue
(2026-05-01)
Pattawee, N.
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Sriprom, P.
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Siriwongwilaichat, P.
Although inulin and polydextrose are widely used as prebiotics to improve the quality and the nutritional properties of food products, their functionality, and optimal levels in coconut milk set yoghurt analogue remain poorly understood due to the fundamentally different matrix compared to dairy yoghurt. The objective of this study was to investigate the effect of inulin and polydextrose fortification on the quality attributes of coconut milk set yoghurt analogues (CYA). Each prebiotic was varied at 1, 3, 5, and 7% (w/v) with a non-prebiotic sample serving as a control. The properties of CYA were then evaluated for pH, titratable acidity, syneresis, and water-holding capacity, firmness, microstructural properties, rheological properties, and sensory acceptability. It was found that the firmness, syneresis, and water-holding capacity of CYA significantly increased with increasing levels of either inulin or polydextrose (p ≤ 0.05). In addition, increasing prebiotics resulted in increasing storage modulus (G՛) and loss modulus (G՛՛). Microstructure observation indicated a finer gel network in CYA fortified with increasing prebiotic up to 5% (w/v). The addition of prebiotics resulted in a considerable increase in viable probiotic counts compared with the control yoghurt. According to sensory evaluation, a significantly improved score (7.41–7.42) was observed in CYA fortified with polydextrose at all concentrations (p ≤ 0.05), whilst that fortified with 5% (w/v) inulin gave the best result. This study demonstrated that inulin and polydextrose can function effectively as structure-forming and functional ingredients in coconut milk set yoghurt analogue, and identifies suitable concentration ranges for improving physicochemical, rheological, microstructural, probiotic, and sensory properties. These findings extend the application of prebiotics to plant-based yoghurt systems and provide practical guidance for the development of high-quality functional non-dairy yoghurt products.
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Microstructure and Mechanical Properties Evolution of P235GH TC1 Steel Fire Tubes from a Fire-Tube Boiler with 14 Tons Capacity and 13 Bars Pressure
(2026-02-01)
Peeratatsuwan, Chaiyawat
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Ariyakul, Yossiri
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Sangsawang, Chatnugrob
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Sukprasertchai, S.
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Chowwanonthapunya, Thee
Comprehensive understanding of the microstructural degeneration and mechanical property degradation is of great importance to evaluate the reliability of used boiler tubes. This study describes the microstructural and mechanical evolution of P 235GH TC1 steel fire tubes which had been used in a fire-tube boiler for 3, 5, and 20 years. The investigation includes visual inspection, dimensional examination, chemical composition analysis, microstructural studies, scanning electron microscopy equipped with energy-dispersive x-ray spectroscopy (SEM-EDX), x-Ray diffraction (XRD), and tensile tests. Results reveal that prolonged exposure to the actual fire boiler environment induced the high temperature and oxidizing atmosphere. This atmosphere facilitated the diffusion and oxidation of carbon and manganese, leading to the depletion of both elements in the aged tubes. The carbon and manganese depletion and the influences of thermal exposure stimulated pearlite decomposition, resulting in the formation of a ferrite-dominated microstructure. The presence of ferrite-dominated microstructure and the deterioration of the solid solution effect due to the carbon and manganese depletion caused a reduction of mechanical performance and plastic deformation resistance of aged tube. The microstructural evolution and mechanical property evaluation indicate the significance of additional microstructural investigation techniques, such as replica examination. This useful method should be included in the routine inspection of the age fire tubes, particularly for those in the prolonged service stage. The addition of this method can improve the reliability of regular inspections, especially for aged fire-tube boilers.
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Foam-mat drying of lucuma powder: Mathematical and artificial modeling of drying kinetics, physicochemical and microstructural properties
(2025-03-01)
Thuy, Nguyen Minh
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Hao, Hong Van
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Duong, Le Thi Thuy
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Giau, Tran Ngoc
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Minh, Vo Quang
The kinetic study of foam-mat drying to make lucuma powder was conducted at various drying temperatures (50–80oC) using thin layer drying and an artificial neural network (ANN) to forecast drying behavior. The physico-chemical properties of lucuma powder under these conditions were also analyzed. Among the six models, the parabolic model was chosen as the best appropriate model for describing the lucuma drying process with the highest correlation coefficient, the lowest RMSE and Chi-square. However, the ANN model (2-10-1) could predict the moisture ratio more accurately than the parabolic model, and it also presented the fittest with the actual experiment. As temperature increased from 50 to 80oC, effective moisture diffusivity increased from 1.05 × 10-9 to 1.67 × 10-9 m2/s, with an activation energy of 15.12 kJ/mol. Drying temperatures have a considerable impact on the quality of lucuma powder. When dried at 60oC, lucuma powder had a bright yellow color, retained its quality and excellent antioxidant activity compared to other temperatures evaluated simultaneously.
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Utilization of ladle furnace slag and fly ash as partially replacement of cement
(2025-03-01)
Thwe, Khin Sam
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Ayawanna, Jiratchaya
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Mase, Lindung Zalbuin
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Chaiyaput, Salisa
Ladle Furnace Slag (LFS) and fly ash (FA) are industrial waste products commonly deposited in landfills, while the cement industry is a major source of carbon dioxide (CO<inf>2</inf>) emissions. Previous research has explored using LFS and FA as cement replacement materials to help mitigate environmental impacts. Yet, no studies have explored combining LFS and FA as cement replacement materials. Therefore, this research highlights the study of the combination of LFS and FA mixes as a partial cement replacement. The mix design for cement replacement materials was developed by combining ordinary Portland cement (OPC), LFS, and FA in the following weight ratios: 10:10:80, 20:20:60, and 30:30:40. These mix designs were assessed in comparison to 100%OPC (% by weight), evaluating key properties (bulk density, specific gravity, normal consistency, setting time, compressive strength, flexural strength, and microstructural characteristics). According to the findings, incorporating LFS and FA, both pozzolanic materials effectively improved the strength of the material by promoting a pozzolanic reaction, particularly during the final stages of curing. Furthermore, it was found that a mixed design containing 20% OPC, 20% LFS, and 60% FA demonstrated suitable properties for cement replacement in various applications, with beneficial results in terms of setting time and strength development. From X-ray fluorescence (XRF) and scanning electron microscope (SEM analysis), C-S-H gel, as well as Ca(OH)<inf>2</inf> and Mg(OH)<inf>2</inf> chemical compounds, were formulated. The aforementioned replacement is being used to promote environmental sustainability through the efficient use of industrial byproducts.
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Influence of electrode shape and material on shear force and microstructure of resistance spot welded AZ80 magnesium alloy
(2025-01-05)
Sangrayub, Phoometh
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Kanlayasiri, Kannachai
Resistance spot welding of AZ80 magnesium alloy is challenging owing to limited understanding of how electrode design and welding parameters interact to influence joint microstructure and strength. This study investigates the effects of electrode shape and material on the shear force and microstructure of resistance spot-welded AZ80 magnesium alloy. Three electrode shapes (A, R, and P) and two electrode materials (ZrCrCu and Al<inf>2</inf>O<inf>3</inf>Cu) were analyzed at welding currents of 13 kA and 17 kA. Nugget size and failure modes were also examined. The results demonstrate that electrode shape and material significantly affect welding heat, nugget size, and joint strength. The fusion zone (FZ) area increased due to the combined effects of welding current, electrode shape, and material. Higher welding heat modified the FZ boundary microstructure, transitioning from cellular morphologies to columnar dendrites, and eventually to equiaxed dendrites, thereby enhancing joint strength. The highest shear force was observed with an R-shaped ZrCrCu electrode at a welding current of 17 kA. However, excessive welding heat reduced the FZ area due to molten metal expulsion. It also promoted the growth of the brittle β-Mg<inf>17</inf>Al<inf>12</inf> phase in the coarse grain heat-affected zone (CGHAZ), shifting the fracture pattern from nugget pull-out to through-thickness in the base metal and decreasing joint strength. This study concludes that selecting appropriate electrodes can mitigate β-Mg<inf>17</inf>Al<inf>12</inf> phase growth in the CGHAZ, highlighting the importance of optimizing welding parameters for improved joint quality in AZ80 magnesium alloy welding.
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PHASE FORMATION AND ELECTRICAL PROPERTIES OF Ba0.91Ca0.09Ti0.916Sn0.084O3-0.1WT%ZnO -0.1WT%MnO2 LEAD-FREE FERROELECTRIC CERAMICS SYNTHESIZED VIA THE SOLID-STATE COMBUSTION METHOD
(2025-01-01)
Yimsabai, Sununta
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Somsri, Widchaya
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Vittayakorn, Naratip
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Charoenthai, Nipaphat
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Suthapintu, Aekasit
This work investigated the effect of firing temperatures on the phase formation, microstructure, and electrical properties of Ba0.91Ca0.09Ti0.916Sn0.084O3-0.1wt%ZnO-0.1wt%MnO2 (BCTS-ZnMn) lead-free ferroelectric ceramics synthesized via the solid-state combustion method. Glycine was used as fuel to reduce the synthesis temperature. The samples were calcined at temperatures from 1050 to 1250°C (in 50°C increments) for 3 h and sintered from 1250 to 1450°C (in 50°C increments) for 3 h. A pure perovskite phase was found in the powders calcined above 1100°C. The phase structure, microstructure, dielectric and ferroelectric properties of the ceramics were examined. The X-ray diffraction (XRD) analysis for the ceramics revealed the presence of tetragonal (T) and orthorhombic (O) phases in all the ceramics. The average particle size and average grain size increased with increasing firing temperatures. The density, dielectric constant at the Curie temperature (ɛc), Pr and Ps tended to increase with increasing sintering temperatures, up to 1400°C, and then decreased at 1450°C. The ceramic sintered at 1400°C exhibited the highest density (5.89 g/cm3), dielectric response (ɛc = 13324) and good ferroelectric behavior (Pr = 8.67 μC/cm2, Ps = 17.92 μC/cm2 and Ec = 0.99 kV/cm).
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ELECTRIC AND MAGNETIC PROPERTIES OF Ni0.475Zn0.475Li0.025Al0.025Fe2O4 DOPED (Bi0.5Na0.5)0.94Ba0.06TiO3 CERAMICS PREPARED BY THE SOLID-STATE COMBUSTION METHOD
(2025-01-01)
Pattanakasem, Wiwat
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Sookboon, Chirarat
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Somsri, Widchaya
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Vittayakorn, Naratip
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Pinitsoontorn, Supree
In this study, we synthesized (1-x)((Bi<inf>0.5</inf>Na<inf>0.5</inf>)<inf>0.94</inf>Ba<inf>0.06</inf>TiO<inf>3</inf>)-x Ni<inf>0.475</inf>Zn<inf>0.475</inf>Li<inf>0.025</inf>Al<inf>0.025</inf>Fe<inf>2</inf>O<inf>4</inf> [(1-x)BNBT-xNZLAF] ceramics with x= 0, 0.05, 0.10, 0.15, and 0.20 using the solid-state combustion method. The phase formation, microstructure, and dielectric, ferroelectric, ferromagnetic, and magnetoelectric properties were investigated. BNBT and NZLAF powders were calcined at 750°C and 900°C for 2 h., respectively. The calcined powders were then mixed in various ratios to produce (1-x)BNBT-xNZLAF composites, which were sintered at 1125°C for 2 h. X-ray diffraction analysis indicated that undoped BNBT ceramics exhibited a typical perovskite structure with coexisting rhombohedral (R) and tetragonal (T) phases. With increasing NZLAF content, the cubic spinel (C) phase emerged with the R and T perovskite phases. Rietveld refinement indicated a higher percentage of the C phase as x increased. When x increased from 0 to 0.10, the average grain size and density increased (from 1.0 to 9.8 m and 5.45 to 5.61 g/cm3, respectively) followed by a drop at higher NZLAF levels. Doping BNBT ceramics with NZLAF resulted in a reduction in the dielectric constant (εr), dielectric loss (tan δ), and remnant polarization (Pr). The undoped BNBT ceramic showed a saturated P-E hysteresis loop, while NZLAF doped ceramics exhibited unsaturated P-E loops and increased leakage current. Magnetic measurements showed a transition from diamagnetic to ferromagnetic behavior with NZLAF doping. As x increased, the remnant magnetization (Mr), saturation magnetization (Ms), and magnetoelectric coefficient also increased (Mr0.058 emu/g, Ms3.594 emu/g, and MEcoefficient 2.64 mV/cm•Oe at x=0.25). These results suggest that NZLAF-doped BNBT ceramics hold potential for multiferroic material applications.
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Modified energy storage properties of lead-free Sr0.3Bi0.35Na0.335Li0.015TiO3 ceramics with La3+ substitution via the solid-state combustion technique
(2024-12-01)
Sinkruason, Thanapon
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Luangpangai, Anupong
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Julphunthong, Phongthorn
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Rittidech, Aurawan
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Suthapintu, Aekasit
In this study, the influence of La3+ substitution on the phase structure, microstructure, electrical and energy storage properties of (Sr<inf>0.3</inf>Bi<inf>0.35</inf>Na<inf>0.335</inf>Li<inf>0.015</inf>)<inf>1-x</inf>La<inf>x</inf>TiO<inf>3</inf> (SBNLT-xLa) ceramics with x = 0–0.05, using the solid-state combustion technique, was investigated. X-ray diffraction (XRD) patterns indicated a pure perovskite structure formed, along with coexisting rhombohedral and tetragonal phases in all ceramics. The Rietveld refinement analysis showed the tetragonal phase increased while the rhombohedral phase decreased with increased La3+ content. The morphology of the SBNLT-xLa ceramics displayed polygonal grain shapes and anisotropic grain growth. Average grain sizes increased from 2.01 to 2.43 μm as x increased from 0 to 0.01 and afterwards decreased as x increased further. Both the measured density and maximum dielectric constant (ɛ<inf>m</inf>) decreased from 5.48 to 5.29 g/cm3 and from 4667 to 2313, respectively, when x increased from 0 to 0.05. A decrease in the dielectric properties caused by the phase ratio shifting away from a morphotropic phase boundary (MPB) condition, poor microstructure and low density was produced with La3+ replacement. The maximum polarization (P<inf>max</inf>), remnant polarization (P<inf>r</inf>) and coercive field (E<inf>c</inf>) decreased with increased La3+ content. A decline in P<inf>r</inf> and E<inf>c</inf> improved the energy storage efficiency (ƞ) and energy storage loss (W<inf>loss</inf>), resulting in enhanced energy storage properties. At x = 0.02, the ceramic showed good energy storage properties (W<inf>total</inf> of 0.781 J/cm3, W<inf>rec</inf> of 0.624 J/cm3, W<inf>loss</inf> of 0.157 J/cm3 and ƞ of 79.8%), measured at 60 kV/cm.
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Spatiotemporal variations of sand hydraulic conductivity by microbial application methods
(2024-01-01)
Kamchoom, Viroon
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Khattiwong, Thiti
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Treebupachatsakul, Treesukon
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Keawsawasvong, Suraparb
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Leung, Anthony Kwan
The spatiotemporal distributions of microbes in soil by different methods could affect the efficacy of the microbes to reduce the soil hydraulic conductivity. In this study, the specimens of bio-mediated sands were prepared using three different methods, i.e. injecting, mixing, and pouring a given microbial solution onto compacted sand specimens. The hydraulic conductivity was measured by constant-head tests, while any soil microstructural changes due to addition of the microbes were observed by scanning electron microscope (SEM) and mercury intrusion porosimetry (MIP) tests. The amount of dextran concentration produced by microbes in each type of specimen was quantified by a refractometer. Results show that dextran production increased exponentially after 5–7 d of microbial settling with the supply of culture medium. The injection and mixing methods resulted in a similar amount and uniform distribution of dextran in the specimens. The pouring method, however, produced a nonuniform distribution, with a higher concentration near the specimen surface. As the supply of culture medium discontinued, the dextran content near the surface produced by the pouring method decreased dramatically due to high competition for nutrients with foreign colonies. Average dextran concentration was negatively and correlated with hydraulic conductivity of bio-mediated soils exponentially, due to the clogging of large soil pores by dextran. The hydraulic conductivity of the injection and mixing cases did not change significantly when the supply of culture medium was absent.
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Microstructure investigation of soft clay after a vacuum PVD second improvement: a case study in Bangkok area Thailand
(2023-10-01)
Chaiyaput, Salisa
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Kotkhangphlu, Pornsuda
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Chao, Kuo Chieh
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Chanin, Chatchai
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Ayawanna, Jiratchaya
This study first demonstrates the microstructural changes of soft Bangkok clay at a real construction site following vacuum PVD modification of soft clay at a − 9-m elevation obtained from Thailand’s Suvarnabhumi Airport. In contrast to the undisturbed soil and the first-improvement soil, the second vacuum PVD improvement transformed the face-to-face orientation of the soil structure into edge-to-face flocculated particles. This approach also greatly affected the inorganic NaCl salts leaching from the pore water, resulting in stronger bonding with less soil permeability and an improved consolidation of soil structure. The repulsive interactions between the soil particles lowered the average liquid limit and plastic limit values, which contributed to the edge-to-face flocculation of the soil particles and greatly increased the shear strength. Vacuum PVD with a second improvement is a highly effective solution for raising the settlement rate and minimizing the settlement time to improve soft clay with low strength and high compressibility.

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