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Rheological Performance of Asphalt Mastics Incorporating Shale and Pumice as Alternative Mineral Fillers
(2026-05-01)
Chamwon, Suwaphit
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Hutabarat, Multazam
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Chaturabong, Preeda
This study investigates the hypothesis that mineral fillers with distinct surface characteristics, mineralogical compositions, and morphologies exhibit different reinforcement mechanisms in asphalt mastics. Shale and pumice were evaluated as alternative mineral fillers and compared with conventional granite and limestone at 20% and 30% filler-to-asphalt (F/A) ratios by volume. Filler characterization included X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), specific surface area (SSA), and hydrophilicity coefficient (HC) measurements. Rheological characterization was performed using dynamic shear rheometer, including temperature sweep, frequency sweep master curves, multiple stress creep recovery (MSCR), linear amplitude sweep (LAS), and Glover–Rowe (G–R) analyses. Pumice, dominated by amorphous volcanic glass with the highest SSA (59.18 m²/g), exhibited rutting-dominant modification with the highest complex modulus enhancement (7.3–9.4 times at 30% F/A) and lowest non-recoverable creep compliance. Shale, composed primarily of quartz and kaolinite with layered morphology and moderate SSA (43.00 m²/g), demonstrated balanced rheological response and achieved the longest fatigue life (Nf,5% = 45,200 cycles at 20% F/A). These findings demonstrate that filler-specific reinforcement mechanisms are governed by mineralogical composition and morphology, supporting performance-based filler selection tailored to climatic and loading conditions.
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EFFECT OF h-BN AS AN ADDITIVE ON PHYSICAL AND MECHANICAL PROPERTIES OF Al2TiO5 COMPOSITE
(2023-01-01)
Treetornkeerati, Paramapat
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Hankoy, Montree
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Kitiwan, Mettaya
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Rodchom, Mana
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Vichaphund, Supawan
Aluminum titanate (Al<inf>2</inf>TiO<inf>5</inf>) is a promising material for high-temperature applications due to its low thermal expansion, high melting point, and excellent corrosion resistance. In this study, the effect of h-BN addition on the properties of Al<inf>2</inf>TiO<inf>5</inf> composites was investigated. The composites were prepared by sintering a mixture of Al<inf>2</inf>O<inf>3</inf> and TiO<inf>2</inf> at a 1:1 molar ratio, with varying amounts of h-BN (5-20 mol%) added to the mixture. The samples were sintered at 1,500ºC for 4 h in N<inf>2</inf> atmosphere, and the bulk density, porosity, phase transition, microstructure, flexural strength, and hardness of the composites were investigated. XRD analysis confirmed the presence of Al<inf>2</inf>TiO<inf>5</inf>, Al<inf>2</inf>O<inf>3</inf>, and Al<inf>18</inf>B<inf>4</inf>O<inf>33</inf> phases in the composites. The addition of h-BN in increasing amounts from 5 to 20 mol% resulted in a gradual improvement in the bulk density, flexural strength, and hardness of the Al<inf>2</inf>TiO<inf>5</inf> composites. The composite with the highest h-BN content (20 mol%) exhibited a bulk density of 3.12 g/cm3, as well as the highest flexural strength and hardness values of 123.6±8.9 MPa and 11.2±4.1 GPa, respectively.
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Microstructure of ITO for Transparent Electrode on Glass Slide Prepare by RF Sputtering Technique
(2021-05-29)
Sangwaranatee, N.
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Srithanachai, I.
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Niemcharoen, S.
Indium tin oxide (ITO) is an absorber photovoltaic material and widely used for semiconductor work for long time. ITO has characteristics by high transparent and low resistivity that can use for electrode of photodetector. Area of photodetector has use for metal contact but if change metal contact to transparent contact will get more photocurrent. However, this paper will investigate microstructure of ITO by analyze physical properties of material by various deposite time. The results show that transparent properties show around 97% at growth 1h and annealing at 500 C. XRD results show ITO peak (222), (400), (622) and (441) at sputtering time 60 mins.
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Physicochemical characterization of forest and sugarcane leaf combustion's particulate matters using electron microscopy, EDS, XRD and TGA
(2021-01-01)
Oo, Hay Mon
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Karin, Preechar
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Chollacoop, Nuwong
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Hanamura, Katsunori
Physical characteristics and quantitative elemental composition of PM and residual ash produced from sugarcane leaves (SCL) combustion were investigated using TEM-EDS compared with forest leaves (FRL). SEM-EDS was used to analyze the microstructure and chemical composition of biomass raw leaves and PM. XRD analysis was also performed to investigate the characterization of the crystalline nanostructure, structure of PM, and residual ash compared to the TEM image processing method. The oxidation kinetics of biomass raw materials, PM, and residual ash were investigated by TGA. The morphology of fine and ultrafine agglomerate structure of SCL soot and residual ash are not significantly different from the FRL soot and residual ash. The average diameter sizes of single primary nanoparticles of SCL and FRL soot are approximately 37 nm and 35 nm, while the sizes of residual ash are about 18 nm and 22 nm, respectively. The single primary nanoparticles of soot are mainly composed of curve line crystallites of carbon fringes, while residual ash is composed of straight-line lattice fringes. The average fringe lengths of SCL and FRL soot are about 1.25 nm and 1.04 nm from the outer shell and 0.89 nm and 0.74 nm from the inner core. The interlayer spacing of curve line carbon fringes of SCL and FRL soot is approximately 0.359 nm and 0.362 nm by the TEM image analysis and it was matched with XRD analysis. The biomass PMs are mainly composed of soot, Si, Ca, and K compounds: SiO<inf>2</inf>, CaCO<inf>3</inf>, and KCl.
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Processing and characterization of amorphous copper oxide thin films prepared by reactive magnetron sputtering
(2018-01-01)
Gaewdang, Thitinai
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Wongcharoen, Ngamnit
In this paper, copper oxide (CuO<inf>x</inf>) thin films with amorphous phase were prepared on glass substrates by reactive dc magnetron sputtering. The influence of the flow rate of O<inf>2</inf> on the structural, optical and electrical properties of the as-deposited films was systematically studied. XRD revealed that the as-deposited films remained amorphous in the whole range of adjusted oxygen flow rate. Surface morphology and nanoparticle size of the films were observed by AFM. Electrical resistivity and Hall effect measurements were performed on the films with van der Pauw configuration. The positive sign of the Hall coefficient confirmed the p-type conductivity in all studied films. From temperature-dependent electrical conductivity of the films prepared at R(O<inf>2</inf>) of 1.5 sccm, it was show that three types of behavior can be expected, nearest-neighbor hopping at high temperature range (200-300 K), the Mott variable range hopping at low temperature (110-190 K) and Efros-Shklovskii variable range hopping at very low temperature (65-100 K). Some important parameters corresponding to Mott-VRH and ES-VRH like density of localized states near the Fermi level (N(E<inf>F</inf>)), localization length (ξ), degree of disorder(T<inf>0</inf>), hopping distance (R) and hopping energy (W) were determined. These parameters would be helpful for optimizing the performance of photovoltaic applications.
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Structural, optical and photoconductive properties of thermally evaporated CdSxTe1-x thin films
(2017-10-01)
Gaewdang, Thitinai
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Wongcharoen, Ngamnit
The formation of a CdS<inf>x</inf>Te<inf>1-x</inf> layer by the interdiffusion of S into the CdTe and of Te into CdS films occurs during the fabrication of CdS/CdTe thin film solar cells. The CdS<inf>x</inf>Te<inf>1-x</inf> layer is thought to be important because the real electrical junction is located in this interdiffused CdS<inf>x</inf>Te<inf>1-x</inf> region. Thus, it is important to have a full understanding of the physical properties of CdS<inf>x</inf>Te<inf>1-x</inf> alloy thin films. In this study, CdS<inf>x</inf>Te<inf>1-x</inf> thin films with composition 0 ≤ x ≤ 1 were prepared by thermal evaporation method on glass substrate using powder of pure CdS and CdTe compounds pressed in pellet form as the source in a vacuum of 5.5 10-5 mbar. X-ray diffraction (XRD) revealed that the films exhibited a cubic zincblende structure with the preferred orientation of (111) plane when x < 0.2. However, when x ≥ 0.8, they had a hexagonal wurtzite structure with the preferred orientation of (002) plane. For the composition 0.2 ≤ x ≤ 0.6, the cubic and hexagonal phases coexisted in the system and the films became less preferentially oriented. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to study the morphological features of the samples. The transmission spectra of the films were studied using a double beam spectrophotometer in the wavelength range of 300-900 nm. Optical band gap value of the films was determined from the transmittance spectra. The variation of band gap (E<inf>g</inf>) with composition (x) of the films was in good agreement with the quadratic form, giving a bowing parameter of (b) =1.85 eV. From the transient photoconductivity measurements, persistent photoconductivity (PPC) behavior was observed. The decay current data fit better with multiple exponential functions, resulting in five slow decay times. The longest carrier lifetime of approximately 6,000 s was observed in the films with x = 0.8. Density of trap states corresponding to decay time was also evaluated from the decay current data.
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Influence of annealing temperature on the properties of SnS thin films prepared by vacuum thermal evaporation
(2017-01-01)
Wongcharoen, Ngamnit
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Gaewdang, Thitinai
SnS thin films were deposited by thermal evaporation in vacuum on glass slide substrate. The as-deposited films were thermally annealed in a controlled N<inf>2</inf> atmosphere with annealing temperature in the range 100-500°C for 30 min. XRD, AFM, UV-VIS transmittance, FTIR and Hall effect measurements were used for characterization the as-deposited and annealed films. Based on the XRD patterns, the as-deposited and annealed films were indentified as the orthrombic structure. The band gap was found to increase from 1.15 to 1.42 eV when the annealing temperature increased from 100 to 500°C. The lowest resistivity and highest carrier concentration values were observed to be 12.95 Ω. cm and 1.98×1016cm-3on the films annealed at 100 and 200°C, respectively.
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Physical properties of CdSxTe1-x thin films prepared by close spaced sublimation method
(2017-01-01)
Gaewdang, Thitinai
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Wongcharoen, Ngamnit
CdS<inf>x</inf>Te<inf>1-x</inf>(0 ≤ x ≤ 1) thin films were prepared on clear quartz glass substrate by close spaced sublimation method using stoichiometric mixed powders of pure CdS and CdTe compounds. Crystal structure of CdS<inf>x</inf>Te<inf>1-x</inf>thin films was cubic structure with a preferential orientation of (111) plane when the S mole ratio less than 0.2. However, For the composition 0.2 ≤ x ≤ 0.8, the cubic and the hexagonal phases were found to coexist in the system and the films became less preferentially oriented whereas CdS thin films formed in the hexagonal phase with a preferential orientation of (002) plane. SEM micrographs showed the grain size decreased when the S content increased. As the S content increased, the energy gap value of CdS<inf>x</inf>Te<inf>1-x</inf>thin films varied from 1.48 eV (for CdTe) to 2.25 eV (for CdS). Dark electrical sheet resistance of CdS<inf>x</inf>Te<inf>1-x</inf>thin films decreased as a function of S content to minimum value about 2.24×107Ω/sq for x=0.8 and then slightly increased to 4.13×107Ω/sq for x=1.0. From the transient photoconductivity measurements, the highest photosensitivity value about 60.0 was obtained for the films with x = 0.8.
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Surface morphology and structural investigation of TiN nanocrystal thin films grown with different N2 concentration
(2013-02-19)
Jiramongkolsiri, Udom
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Thanomngam, Pitiporn
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Pankiew, Apilak
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Porntheerapat, Supanit
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Nukeaw, Jiti
In this work, new information on surface morphology, phase and local structure of titanium nitride (TiN) nanocrystal thin films grown with different nitrogen gas concentration by direct current (DC) magnetron sputtering is provided. Surface morphology of the thin films was studied by field emission scanning electron microscope (FE-SEM). Phase and local structure of the TiN nanocrystals were determined by X-ray diffraction spectroscopy (XRD) and X-ray absorption fine structure (XAFS). The TiN nanocrystals were prepared on silicon substrates. N<inf>2</inf>/Ar gases were used as reactive gases for sputtering Ti target. The amount of these two reactive gases was varied at different ratios (N<inf>2</inf>/Ar), i.e. 100:0, 75:25, 50:50 and 25:75 respectively. Our results suggested that sputtering Ti target with high N<inf>2</inf>/Ar gas ratio (higher than 75%) provides good TiN layer while sputtering with low N<inf>2</inf>/Ar gas ratio (lower than 25%) gives Ti layer instead of TiN. In addition, sputtering with 50% N<inf>2</inf>/Ar gas ratio gives a multiphase system between TiN and Ti. Local structure parameters of these nanocrystal thin films are reported. © (2013) Trans Tech Publications, Switzerland.
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A rapid synthesis of blue-pigment copper cyclotetraphosphate (cu2P4O12) ricelike grain nanoparticles at low temperature
(2012-12-01)
Chatjuthamanee, Warunthip
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Muanghlua, Rangson
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Boonchom, Banjong
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Vittayakorn, Naratip
A blue-pigment copper cyclotetraphosphate Cu<inf>2</inf>P<inf>4</inf>O<inf>12</inf> was synthesized by a simple wet preparation method using copper oxide and phosphoric acid at 350 °C. The crystallite size obtained from X-ray line broadening is 53 ± 11 nm for the Cu<inf>2</inf>P<inf>4</inf>O<inf>12</inf>. The FTIR spectrum of Cu<inf>2</inf>P<inf>4</inf>O<inf>12</inf> is assigned a base on the P<inf>4</inf>O<inf>12</inf>4- ion in the structure, which indicates the most striking feature of cyclotetraphospate. XRD and FTIR results of the synthesized CuCu<inf>2</inf>P<inf>4</inf>O<inf>12</inf> indicate the pure monoclinic phase with space group C<inf>2h</inf>6 (C2/c). SEM micrographs of the synthesized Cu<inf>2</inf>P<inf>4</inf>O<inf>12</inf> show rice-like grains, a porous structure and agglomerations, which are important for a specific application. The UV-Vis-NIR spectrum confirms the octahedral coordination of the Cu (II) ion and blue pigment.

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