Nakhon Ratchasima, Thailand
Nakhon Ratchasima, Thailand

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Kittimanapuny K.,Synchrotron Light Research Institute SLRI | Chanlek N.,Synchrotron Light Research Institute SLRI | Juntong N.,Synchrotron Light Research Institute SLRI | Cheedket S.,Synchrotron Light Research Institute SLRI | And 4 more authors.
IPAC 2016 - Proceedings of the 7th International Particle Accelerator Conference | Year: 2016

The SLRI Beam Test Facility (SLRI BTF) is a part of the future upgrades of the SLRI accelerator complex. Upon completion, SLRI BTF will be able to produce electron test beams with the number of electrons ranging from a few to several thousand electrons per bunch. The project is divided into three stages based on the complexity of the electron reduction setups. The simple setup for the initial stage has been implemented without any modifications to the current High-energy Beam Transport line (HBT) while additional elements together with an existing 4-degree dipole are required for the short-term setup in the second stage. For the last stage, a new dedicated transfer line equipped with a high-resolution energy selector will be constructed to direct the electron beam from the HBT beam line to an experimental station. This project aims to provide a defined number of electrons with maximum energy of 1 GeV for calibration and testing of high energy detectors as well as other beam diagnostic instrumentations. Copyright © 2016 CC-BY-3.0 and by the respective authors.


Worabut A.,King Mongkut's University of Technology Bangkok | Thammajak N.,Synchrotron Light Research Institute SLRI | Suwanpinij P.,King Mongkut's University of Technology Bangkok
Key Engineering Materials | Year: 2017

High Strength Low Alloy (HSLA) steels or microalloyed steels are developed in order to improve the strength and toughness compared with conventional carbon steels. During the reheating process at 1250-1300°C for a few hours, the furnace consumes large amount of energy, and the slab suffers from thick oxide scale. This results in significant mass loss. The long reheating time ensures maximum dissolution of the microalloying elements, which must be kept to precipitate during cooling at the end of the hot rolling process. To minimise the reheating time and save the energy consumption, this research studied the dissolution kinetics of vanadium in HSLA steel. Vanadium is a main microalloying element added to provide higher strength mainly by precipitation hardening. It is supposed to be dissolved readily according to the solubility limit. The samples were reheated to 1200°C and 1250°C for 0, 10, 30, and 60 s. After that the fraction of vanadium dissolved in the solid solution and the remaining undissolved phases of VC, CN, and V(C,N) were measured by synchrotron XAS. As soon as the sample reaches as low temperature as 1200°C, a large atomic fraction of 0.878 of vanadium can be dissolved in the solid solution. © 2017 Trans Tech Publications.


Tangcharoen T.,King Mongkut's University of Technology Thonburi | Tangcharoen T.,Synchrotron Light Research Institute SLRI | Klysubun W.,Synchrotron Light Research Institute SLRI | Kongmark C.,Synchrotron Light Research Institute SLRI | And 2 more authors.
2014 IEEE International Nanoelectronics Conference, INEC 2014 | Year: 2014

The non-equilibrium site occupancy of zinc (Zn2+) and ferric (Fe3+) ions in dissimilar nanosized zinc ferrites (ZnFe2O4)powders obtained from the different milling time (0 to 24 h) of the as-combusted powders was investigated through Zn and Fe K-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra. Compared with the bulk specimen of zinc ferrite, both XANES and EXAFS spectra of nanosized zinc ferrite powders clearly exhibit the large Zn2+ ions translocation from the tetrahedral (A) sites to the octahedral (B) sites leading to the movement of many Fe3+ ions in the opposite direction without the variation in the long-range structural order. © 2014 IEEE.


Tangcharoen T.,King Mongkut's University of Technology Thonburi | Tangcharoen T.,Synchrotron Light Research Institute SLRI | Ruangphanit A.,Thai Microelectronics Center | Klysubun W.,Synchrotron Light Research Institute SLRI | Pecharapa W.,King Mongkut's University of Technology Thonburi
Journal of Sol-Gel Science and Technology | Year: 2013

Nanocrystalline Ni-substituted Zn ferrites with compositions of Ni xZn1-xFe2O4 (x = 0-1.0) were synthesized by sol-gel auto-combustion method using metal nitrate as the reactants. Diethanolamine was selected as the fuel instead of conventional fuels such as urea, citric acid, tartaric acid or glycine. Characterization of after-calcined ferrite samples were conducted in terms of crystal structure, molecular vibrations, morphology and magnetic properties through X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope and vibrating sample magnetometer analysis, respectively. The photocatalytic activities of these ferrites were studied in term of degradation of Rhodamine B under daylight-irradiation. The corresponding results indicate that nickel loading content has significant effect on physical, magnetic, optical and photocatalytic properties of the ferrite. Comparing to the undoped Zn ferrite, Ni0.6Zn0.4Fe2O4 shows the enhancement in photocatalytic activity accompanying the degradation of Rhodamine B aqueous solution up to 77 % within 4 h. The result suggests the feasibility of this material as potential sunlight-activated photocatalyst in wastewater treatment and environment cleaning applications. © 2013 Springer Science+Business Media New York.


Tangcharoen T.,King Mongkut's University of Technology Thonburi | Tangcharoen T.,Synchrotron Light Research Institute SLRI | Klysubun W.,Synchrotron Light Research Institute SLRI | Ruangphanit A.,Thai Microelectronics Center | Pecharapa W.,King Mongkut's University of Technology Thonburi
Integrated Ferroelectrics | Year: 2014

In this work, the physical structure, magnetism and local structure of zinc and nickel ferrites (ZnFe2O4 and NiFe2O 4) synthesized by typical sol-gel combustion method, were investigated by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). The formation of the single phase cubic spinel crystal structure and the different values of crystallite size (D), interplanar distance (d) and lattice constant (a) for all ferrite samples were evaluated by the XRD data. The VSM measurement provides the characteristic magnetic hysteresis loop (M-H) for each sample which was found to be significantly different from each other. The chemical shifts in Zn, Ni and Fe K-edges XANES spectra indicate the existence of Zn2+, Ni2+ and Fe3+ ions in these ferrites. The EXAFS spectra analyses applied to track Zn, Ni and Fe cation distribution indicate the distinct character of spinel crystal structure of both ferrites. The results exhibit that zinc ferrite is a normal spinel, while the nickel ferrite is an inverse spinel. Moreover, these EXAFS spectra analyses reveal that the distances between metal ion (Zn2+ or Ni2+) to central oxygen ion and to Fe3+ ions in the opposite lattice site for each ferrite sample are unequal which highly affect its magnetism. The overall simulated results are one of the important evidence encouraging the explanation on the paramagnetism for ZnFe2O4 and the ferrimagnetism for NiFe2O4. © 2014 Taylor & Francis Group, LLC.


Tangcharoen T.,King Mongkut's University of Technology Thonburi | Tangcharoen T.,Synchrotron Light Research Institute SLRI | Klysubun W.,Synchrotron Light Research Institute SLRI | Kongmark C.,Synchrotron Light Research Institute SLRI | Pecharapa W.,King Mongkut's University of Technology Thonburi
Physica Status Solidi (A) Applications and Materials Science | Year: 2014

In this work, the metal ferrites MFe2O4 (M = Ni, Mn, Cu) were synthesized from metal nitrate precursors by the sol-gel auto-combustion method using diethanolamine (DEA) as a potential fuel. The crystal structures of these ferrite powders were characterized by X-ray diffraction (XRD) technique confirming the complete formation of the single-phase cubic spinel crystal structure. The ferrimagnetism characteristic and the difference of the magnetic properties such as saturation magnetization (Ms), remanent magnetization (Mr), and coercivity (H c) for each after-calcined ferrite sample were scrutinized through the ferrimagnetic hysteresis loop (M-H) obtained from the vibrating sample magnetometer (VSM) measurement. Moreover, the cation distribution and valence state of these ferrites were investigated by the Ni, Mn, Cu, and Fe K-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra using the synchrotron radiation light source. From the XAS results, the analyses of both XANES and EXAFS spectra show the existence of accurate oxidation state for transition metal ions and the interionic distance to the nearest neighbors in the spinel crystal structure. In particular, the curve-fitting analysis of Ni, Mn, Cu, and Fe K-edge EXAFS spectra indicates that the degree of inversion in these metal ferrites is entirely different and found to be 0.2 for MnFe2O4, 0.8 for CuFe2O 4, and 1.0 for NiFe2O4, which are the important information for understanding their effects on relevant magnetic properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Tangcharoen T.,King Mongkut's University of Technology Thonburi | Tangcharoen T.,Synchrotron Light Research Institute SLRI | Kongmark C.,Kasetsart University | Klysubun W.,Synchrotron Light Research Institute SLRI | Pecharapa W.,King Mongkut's University of Technology Thonburi
International Journal of Nanotechnology | Year: 2016

The zinc ferrite (ZnFe2O4) powders of various nanoparticle sizes were synthesised at different milling times (0 to 24 h) of the as-combusted powders. The non-equilibrium site occupancy of zinc (Zn2+) and ferric (Fe3+) ions was investigated through Zn and Fe K-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra. The XRD and SEM strongly confirm the particle size of these ferrites decreasing with the increasing milling time. Compared with the bulk specimen of zinc ferrite, both XANES and EXAFS spectra of zinc ferrite powders clearly exhibit the large translocation of Zn2+ ions from the tetrahedral (A) sites to the octahedral (B) sites and the opposite translocation of some of Fe3+ ions without affecting the long-range structural order. Moreover, the curve-fitting analysis of Zn and Fe K-edge EXAFS spectra indicates that the degree of inversion increases as the particle size decreases resulting in significant differences in the magnetic behaviours.


Galbraith S.C.,Suranaree University of Technology | Flood A.E.,Suranaree University of Technology | Flood A.E.,Vidyasirimedhi Institute of Science and Technology | Rugmai S.,Synchrotron Light Research Institute SLRI | Chirawatkul P.,Synchrotron Light Research Institute SLRI
Chemical Engineering and Technology | Year: 2016

Potential mechanisms affecting growth rate dispersion (GRD) are investigated. Previous studies have identified surface roughness and internal lattice perfection as key mechanisms which are both evaluated with respect to GRD. Crystal growth of potassium dihydrogen phosphate was studied in two solvent mixtures, water and water-ethanol. The surface roughness was analyzed by atomic force microscopy and the internal crystal perfection by X-ray diffraction using a synchrotron source. The crystals grown at higher supersaturation have more pronounced and more frequent surface irregularities, supporting previous findings on a feedback mechanism between surface roughness and growth rate. No significant relationship was found between internal crystal perfection and growth rate, however, this is likely due to the size of the crystals analyzed herein and not the absence of any such mechanism in small crystals. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wongpanya P.,Suranaree University of Technology | Wongpinij T.,Synchrotron Light Research Institute SLRI | Photongkam P.,Synchrotron Light Research Institute SLRI | Euaruksakul C.,Synchrotron Light Research Institute SLRI | Witit-Anun N.,Burapha University
Materialpruefung/Materials Testing | Year: 2015

TiAlN films with thicknesses of 250, 500 and 750 nm were deposited on 4140 steel using the reactive direct current co-unbalanced magnetron sputtering method. The effects of the film thickness on the microstructure were revealed using a field emission scanning electron microscope, an image analyzer and X-ray diffraction. The results showed that grain size apparently increased when the film was at greater thicknesses whereas porosity, lattice strain and dislocation density decreased. Meanwhile, the results of anodic polarization tests in air-saturated 3.5 wt.-% NaCl solution at pH levels of 2, 7 and 10 and at 25°C showed lower corrosion potential in thicker film, attributed to a lower ratio of grain boundary area to individual grain area. However, a more stable passive film with higher pitting potential was formed. By analyzing using X-ray absorption spectromicroscopy, oxidation of Ti into TiO2 was found on the corroded surface of TiAlN film. © Carl Hanser Verlag, München.


Patton R.,University of Hull | Chen L.,University of Hull | Klinkhieo S.,Synchrotron Light Research Institute SLRI
International Journal of Applied Mathematics and Computer Science | Year: 2012

The concept of combining robust fault estimation within a controller system to achieve active Fault Tolerant Control (FTC) has been the subject of considerable interest in the recent literature. The current study is motivated by the need to develop model-based FTC schemes for systems that have no unique equilibria and are therefore difficult to linearise. Linear Parameter Varying (LPV) strategies are well suited to model-based control and fault estimation for such systems. This contribution involves pole-placement within suitable LMI regions, guaranteeing both stability and performance of a multi-fault LPV estimator employed within an FTC structure. The proposed design strategy is illustrated using a nonlinear two-link manipulator system with friction forces acting simultaneously at each joint. The friction forces, regarded as a special case of actuator faults, are estimated and their effect is compensated within a polytope controller system, yielding a robust form of active FTC that is easy to apply to real robot systems.

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