Research Publications

Academic theses and dissertations are regularly published and widely disseminated in YUOE Journal, Monographs, Universities Research Journal (URJ), Myanmar Academy of Arts and Science (MAAS) Journal, AsTEN Research Journal and International online Journals for sharing knowledge and contributing to the development of our education.

Myanmar Academy of Art & Science List of Research

No. Researcher Title Abstract Year
1571 Nwe Wai EFFECT OF COMPLEXING AGENT (Na2EDTA) ON THE DEPOSITION OF COPPER TIN SULPHIDE THIN FILMS Copper tin Sulphide (CTS) thin films were prepared by chemically bath deposited in aqueous solutions containing sources of copper, tin and sulphur. The effect of different molar concentration of complexing agent on the growth of thin films was reported. The structure, optical and surface topography characteristics of thin films of copper tin sulphide grown on glass substrates were investigated by X-ray diffraction, UV-Vis spectrophotometry and atomic force microscopy techniques. The X-ray diffraction showed that the most prominent peak at 2? = 50.60° which belong to (223) plane of Cu4SnS4. The atomic force microscopy indicated that the film deposited at the concentration of 0.1 M complexing agent exhibited narrow optical band-gap which is the requisite for light absorber layer in solar cell application. The band gap energy was found to be 1.5 eV with direct transition. 2021
1572 Nay Min Aung CODE TRACKING FOR GPS SIGNAL PROCESSING This paper presents the code tracking method for software defined GPS receiver. A number of methods have been developed to enhance the robustness of Global Positioning System (GPS) receivers when there are a limited number of visible satellites. In this work, code tracking method is developed to improve the accuracy of positions of GPS receiver. The GPS signal consists of the navigation data, the carrier and code sequences for each of the satellite. The signal of each satellite is demodulated using Delay Lock Loop (DLL) for code tracking. The code tracking output errors feedback to Numerically Control Oscillator (NCO) frequency for exact signal lock between GPS signal and NCO signal. In position calculation, each channel of code is controlled by individual loop filter. The code tracking method for software defined GPS receiver is implemented by using MATLAB. 2021
1573 Pwint Yi Thein STUDY ON EFFECT OF ISOVALENT BARIUM IONS SUBSTITUTION ON STRUCTURAL FEATURES, FERROELECTRIC PROPERTIES AND BANDGAPS OF LEAD TITANATE Isovalent Ba ions substituted lead titanate is studied by means of its structural features, ferroelectric properties and bandgaps. Analar grade PbO, TiO2 and BaCO3 are chosen and used as starting materials. Three starting materials are weighted and mixed by the stoichiometric composition: Pb(1 – x) Ba(x), TiO3, where x = 0, 1 mol%, 2 mol%, 3 mol%, 4 mol% and 5 mol% respectively. The mixture powders are grinded by using agate mortar for each 5 hrs. Then, the mixture powders are conventionally sintered at 700°C for each 5 hrs. After first sintering process, the mixture powders are grinded again by using ball milling for each 5 hrs. Finally, the mixture powders are sintered at 700°C for each 5 hrs. X – rays diffraction technique is used to examine the phase formation and structural features of PbTiO3:Ba specimens. From the XRD studies, lattice constants, lattice distortion, unit cell volume, crystallite size and lattice micro strain are estimated. Ferroelectric properties of PbTiO3:Ba specimens are characterized by using Sawyer – Tower circuit. Spontaneous polarization, remaent polarization and coercive field of PbTiO3:Ba specimens are evaluated. Optical bandgaps of PbTiO3: Ba specimens are studied by using UV – Vis spectrophotometer. From the absorption spectra, bandgaps are calculated. XRD results indicates that, there are no significant change of tetragonal perovskite type PbTiO3 structure after Ba substitution. A little changes of structural features are observed and it is due to appearance of micro strain and defects, dislocations and vacancies in host PbTiO3 structure during the doping mechanism. Ferroelectric properties, such as spontaneous polarization, remanent polarization and coercive field slightly increase as additional Ba content increases, due to second- order hybridizations, caused by isovalent Ba ions in PbTiO3 lattice. Optical bandgap of PbTiO3 is enhanced when additional Ba content is raised. It is expected that, there are a quantum confinement effect in PT: Ba specimens. 2021
1574 Cho Cho Khin EFFECT OF SINTERING TEMPERATURE ON STRUCTURAL AND MECHANICAL PROPERTIES OF BETA-TRICALCIUM PHOSPHATE ?-tricalcium phosphate powders were synthesized by the wet chemical precipitation method starting from calcium nitrate tetrahydrate, Ca(NO3)2.4H2O, and diammonium hydrogen phosphate, (NH4)2HPO4. The pH of the mixed solution was controlled at pH-10 by adding sodium hydroxide solution. The ?-TCP pellets were sintered at 800°C, 900°C, 1000°C, and 1100°C for 6 h each. The structural and mechanical properties of ?-TCP pellets were characterized by using XRD, SEM, Hardness tester, and Archimedes’ method respectively. The dense microstructure without pores could be obtained at the sintering temperature of 1100°C. The hardness and compressive strength increased with increasing temperature. The maximum compressive strength of ?-TCP pellets was obtained at 1100°C. The behavior of bioceramic was investigated such that porosity decreased when the bulk density and temperature increased accordingly. In this research, the sintering temperature at 1100°C provided maximum density and hardness which may be applied as a bone replacement. 2021
1575 Ni Lar STRUCTURE CHARACTERIZATION OF TITANIUM DIOXIDE FILMS ON SILICON SUBSTRATE Transparent semiconducting thin films of titanium dioxide (TiO2) were deposited on silicon substrate by the spray method. The microstructure of the TiO2 films were characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Raman Spectroscopy. The XRD analysis revealed that the films were polycrystalline with an anatase crystal structure and a preferred grain orientation in the (101) direction. Strong LO-phonon Raman spectra modes especially B1g (393.29 cm-1 ) and Eg (634.84 cm-1 ) in Raman spectra and the absorption peak at 739 cm-1 in absorbance spectra by FTIR also indicated the existence of anatase phase TiO2 in these films. 2021
1576 Su Su Tha INFLUENCE OF COPPER SUBSTITUTION ON ELECTRICAL PROPERTIES OF Mg-Cu-Zn FERRITE Magnesium copper zinc ferrites with the general formula Mg0.5CuxZn0.5-xFe2O4(x=0, 0.1, 0.2, 0.3, 0.4, 0.5) were prepared by mixing stoichiometric proportions of magnesium, copper, zinc and ferrite nitrates with calculated amount of citric acid. Before mixing, four raw samples were checked by XRD to confirm these samples are pure or not. Four raw samples, magnesium nitrates: copper nitrate: zinc nitrates: ferric nitrates (Mg(NO3)2.6H2O, Cu(NO3)2.6H2O, Zn(NO3)2.6H2O, Fe(NO3)3.9H2O) were mixed with citric acid (C6H8O7) in different ratios in the beaker and stirring at 70°C until to get viscous gel. And then the samples were calcined at 800?C for 2 hr. The structural analysis, crystallize size and surface morphology investigation of as prepared samples were studied by Powder X-ray Diffractometer (XRD) and Scanning Electron Microscopy (SEM) techniques. The temperature dependent resistivity of Mg-Cu-Zn ferrites were analysis in various concentration of copper. 2021
1577 Hnin Yu Khaing OPTICAL AND ANTIBACTERIAL PROPERTIES OF COLLOIDAL GOLD NANOPARTICLES Colloidal gold nanoparticles in spherical shape had been synthesized from chloroauric acid (HAuCl4) by one of the solution method such as chemical reduction method. The colloidal gold nanoparticles were characterized with scanning electron microscopy (SEM) for morphological properties, X-ray diffraction method (XRD) for structural analysis and UV-VIS absorption spectroscopy for optical properties. It was found that the concentration of the precursors solution affected the size of the nanoparticles. In this nanoparticles fabrication method, the size of nanoparticles could be controlled by varying amount of sodium citrate. The antibacterial properties of gold nanoparticles had been studied. 2021
1578 Mono Zaw EFFECTS OF ANNEALING TEMPERATURE ON OPTICAL AND ELECTROCHEMICAL PROPERTIES OF SPRAY-PYROLYSED WO3 FILMS Tungsten trioxide (WO3) thin films were coated onto fluorine tin oxide (FTO) coated glass substrates by spray pyrolysis technique and annealing at different temperatures (300oC, 400oC and 500oC). The presented work studied the effect of annealing temperature on the surface morphology, optical and electrochemical properties of WO3 films by using scanning electron microscopy (SEM), atomic force microscopy (AFM), UV-vis spectroscopy and cyclic voltammetry (CV). Optical study showed that the decreased optical transmission and band gap was observed in WO3 film at higher annealing temperature (400oC and 500oC). The electrochemical study revealed that anodic peak current density was higher in WO3 film annealed at 400oC in KI electrolytic solution. Upon modulating the annealing temperature, change in optical and electrochemical properties of WO3 films was correlated to surface morphology change in WO3 films. 2021
1579 Kyaw Kyaw SYNTHESIS AND OPTICAL PROPERTIES OF TITANIUM DIOXIDE NANOPARTICLES USING SOL-GEL METHOD The main objective of this research work was to synthesize and to characterize titanium dioxide (TiO2) nanoparticles using sol – gel method with different weight ratio of NaOH. The optical properties and band gap energies of obtained nanoparticles were investigated with UV-Vis spectroscopy. The crystal structural and morphological properties of fabricated TiO2 nanoparticles were characterized with XRD and SEM techniques. From the results of investigating methods, it was revealed that the fabricated particles were good agreement with standard physical properties of TiO2 nanoparticles and they could be used in Solar cells, waste water treatment and industrial applications. 2021
1580 Nu Nu Swe CONTROLLING THE APPLIANCES AND MONITORING DATA FROM LOCAL WEB SERVER USING ESP32 AND HTML Physical data can be sending (writing) to or receiving (reading) from the web server using ESP32 which is a device of combination of microcontroller and Wi-Fi, generally. Physical data such as temperature, humidity and voltage are detected (read condition) from the DHT11 sensor and potentiometer by using microcontroller and these are monitored on web page. And then, the home appliance can be controlled by the touching or clicking the word or symbol on the web page on laptop or smart phone as writing action. In this research, a LED is controlled instead of the home appliance and the potentiometer is used behalf of voltage source to be measured. ESP32 is compatible to Arduino IDE but ESP32 board is not included in Arduino IDE as default. The board is installed in the IDE. Coding composes of data writing to / reading from web, connecting to web server and web page management. Web page is created by using hypertext markup language (HTML). 2021