Advanced Materials Research Vol. 979

Abstract: In this work, glass furnace for research scale has been fabricated using domestic raw materials. Furnace was designed and assembled in laboratory for reduce the heat loss due to openings when load out crucible from furnace, reduce energy cost and increase the number of glass samples that can be made in one working time. Glasses based soda lime silicate formulas have been prepared using the normal melt-quench technique for furnace testing. The result found that good optical properties and physical properties of glasses were obtained.

Abstract: Samarium doped bismuth borate glasses with composition 66.7Bi₂O₃ : (33.3-x)B₂O₃ : x Sm₂O₃ (where x = 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) have been prepared by melt quenching technique. The physical, optical, photoluminescence and X-rays luminescence properties were investigated. The densities and molar volumes were not found the relationship with the increasing samarium concentration. The photoluminescence emission spectra shows broad emission bands due to ⁴G_5/2→⁶H_J (J=5/2, 7/2, 9/2, 11/2) transitions when excited with 473 nm. The decay curves of ⁴G_5/2 level exhibited single exponential behavior for all the concentrations and the measured lifetimes are found to depend strongly on samarium concentrations. The X-rays emission spectra were measured at the X-rays of intensity 100kV and current 1.5mA. The emission peaks observed at 569, 598, 641 and 705 nm. And the intensity of luminescence increase as samarium concentration increase.

Abstract: This research is the study of electric power generated by the temperature difference below 100 °C of thermoelectric effect (cooling devices), which gets power from direct current and the electromotive force from thermoelectric module. In this research, a testing kit was designed to collect the output of temperature difference on the thermoelectric device, and compared the level of electric power of various modules in 2 different circuits; series and parallel. The result of the study showed that the higher differential temperature increased the value of electricity generation. Also, the electrical connection of thermoelectric module had an effect on power generating. When using 2 modules for each circuit, the series circuit generated more power than the parallel circuit.

Abstract: This research studies the alternative way of electricity generating from the waste heat of economy oven by using 4 modules of thermoelectric modules. The hot side of thermoelectric module is attached to the heat plate while the cold side is installed on the rectangular, plate-fin heat exchanger. Variety of system adjustments were used during this study in terms of finding the maximum electric power rate. Adjusting the heating value and the electrical resistance to the thermoelectric was the procedure in this study. From the research, we found out that at the temperature of 200°C on the heat pad, the released maximum electric current was 4.5 W. The percentage of heat converting to electric current was 11.9%, with the 0.84 A and 5.35 V. The efficiency of the economy oven was 23.20%, and comes up to 23.39% while generating power via thermoelectric module.

Abstract: The total mass attenuation coefficient, partial photon interaction and effective atomic number of commercial window added with BaSO₄ in have been investigated at photon energy from 1 keV to 100 GeV on the basis of calculation. The theoretical values of total and partial interaction were obtained by the WinXCom software. The variations of mass attenuation coefficient and effective atomic number with photon energy are shown graphically. The results show that the variation of mass attenuation coefficient and effective atomic number has changed with photon energy and composition of window. It has been found that these parameters increase with increasing BaSO₄ concentrations, due to the increasing photoelectric absorption in glass samples. These results showed that the BaSO₄ can improve radiation shielding properties in commercial glass and useful for radiation shielding material design.

Abstract: In this article, amorphous tantalum oxide thin films were deposited by dc reactive magnetron sputtering onto silicon (001) wafer and glass slide substrates. Sputtering power has been varied for optimizing thin film quality. The structural and optical properties of the Ta₂O₅ thin films were investigated by using X-ray diffraction, UV-Vis spectrophotometer and spectroscopic ellipsometry respectively. The XRD pattern result indicates that the films are amorphous. It was found that the growth rate was also increased with increasing dc power up to 250 W, and the maximum growth rate observed at 250 W was 0.25 nm/s. In addition, the refractive index and packing density of the films increases with increasing dc sputtering power.

Abstract: The structural transformations of chicken eggshell sample upon heat treatments and water absorption have been studied after having ground the shells into powders. Structural identifications of chicken eggshell samples were performed by using x-ray diffraction, IR spectroscopy and Energy Dispersive X-rays spectrometer (EDXRF). It was found that the specimen is made of calcite, a common phase of CaCO₃ mineral. An then annealing at different temperatures in the range of 300-600C, The chicken eggshell not transformation, but after heat treatment at temperature 900C, the chicken eggshell sample have been transform structural in to oxide compound with calcia phase. In addition, the chicken eggshells have been preparation calcium hydroxide via a water steam route.

Abstract: The chemical and physical properties of topsoil and subsoil which collected from the cassava cropping area in Chonburi Province have been investigated. The characterization of both soil sample were used X-Ray Diffraction (XRD), Energy Dispersive X-Ray Fluorescence (EDXRF) while FTIR used to confirmed the formation of intermolecular bonding and Thermo-Gravimetric Analysis (TGA) used for investigated the crystalline. It was found that, the XRD pattern indicated quartz phase. The chemical composition by XRF reported that the soils samples consist of Si, Al, Ca, Fe, K, Mn, Ti, Cr, Zn, Ag and Cu. and TGA results, noticed that the removal of moisture and organics material.

Abstract: The aim of this study is to investigate the some chemical and physical properties in the soils collected from the paddy rice fields in Chonburi Province. The chemical analysis of soil samples was performed on an Energy Dispersive X-rays spectrometer (EDXRF). It was found that the soils samples consist of Si, Al, Ca, Fe, K, Mn, Ti, Cr, Zn, Ag and Cu. Another that, the structural in whole soil samples were carried out by X-ray Diffraction (XRD) technique. It was found that Silica (SiO₂) is the major minerals in all soil layers. In this study, we also used Thermo-Gravimetric Analysis (TGA) investigated the removal of moisture from the paddy rice fields.

Abstract: Tantalum oxide (Ta₂O₅) thin films have been deposited on glass substrates and silicon wafers (100) by dc reactive magnetron sputtering and with a 99.995% pure tantalum target. The effect of the oxygen flow rate on the crystallinity and optical properties were investigated. The films were characterized by X-ray diffraction patterns, UV-Vis spectrophotometer and spectroscopic ellipsometry. The results show that the deposition rate of Ta₂O₅ thin films was decreased with the increase in oxygen flow rate. In addition, Ta₂O₅ thin films deposited at oxygen flow rate higher than 6 sccm could be exhibited sufficiently oxide thin film, the transmittance spectrum percentage indicated 80%, which corresponded to the obtained optical characteristic.