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"Transparent conducting oxide (TCO) glasses play an important role invarious technology, including dye sensitized solar cells. One of the mostcommonly used glass is indium tin oxide (ITO) glass, which is expensive.Therefore, the mainpurpose of this research was to determine if ITO glass can be replaced withfluorine-doped tin oxide (FTO) glass,which is easier and more economic to manufacture. For this purpose, a tinchloride dehydrate (SnCl2.2H2O)precursor was doped with ammoniumfluoride (NH4F) using asol-gel method and spray pyrolysis technique toinvestigate the fabrication process for conductiveglass. NH4F wasdoped at a ratio of 2 wt% in the SnCl2.2H2O precursor atvarying deposition times (10, 20, and 30 minutes) and substrate temperatures(250, 300, and 350°C). Theresults revealed that longer deposition times created thicker glass layers withreduced electrical resistivity. The highest opticaltransmittance was 75.5% and the lowest resistivitywas 3.32´10-5 Ω.cm,obtained from FTO glasssubjected to a 20-minute deposition time at deposition temperature of 300oC."

"Transparent conducting oxide (TCO) glasses play an important role in various technology, including dye sensitized solar cells. One of the most commonly used glass is indium tin oxide (ITO) glass, which is expensive. Therefore, the main purpose of this research was to determine if ITO glass can be replaced with fluorine-doped tin oxide (FTO) glass, which is easier and more economic to manufacture. For this purpose, a tin chloride dehydrate (SnCl2.2H2O) precursor was doped with ammonium fluoride (NH4F) using a sol-gel method and spray pyrolysis technique to investigate the fabrication process for conductive glass. NH4F was doped at a ratio of 2 wt% in the SnCl2.2H2O precursor at varying deposition times (10, 20, and 30 minutes) and substrate temperatures (250, 300, and 350°C). The results revealed that longer deposition times created thicker glass layers with reduced electrical resistivity. The highest optical transmittance was 75.5% and the lowest resistivity was 3.32´10-5 ?.cm, obtained from FTO glass subjected to a 20-minute deposition time at deposition temperature of 300oC."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 Ω/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"Fluorine-doped tin oxide (FTO) is one of the conductive glasses that have strategic functions in various important applications, including dye-sensitized solar cell (DSSC). In the current work, the effects of deposition time (5, 10, 20, 30, and 40 minutes) upon the fabrication process of FTO thin film using spray pyrolysis technique with modified ultrasonic nebulizer has been studied in regard to its microstructural, optical, crystallinity, and resistivity characteristics. The variation was also performed by comparing the pure tin chloride precursor and the solution that was doped with fluor (F) at 2 wt% in order to see the doping effect on the properties of thin film. The thin films were characterized using x-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectroscopy, and digital multimeter. On the basis of current investigation, it has been found that the best FTO was obtained through the pyrolysis technique of 20-minute deposition time, providing optical transmittance of 74%, a band gap energy (Eg) of 3.85 eV and sheet resistance (Rs) of 7.99 ?/sq. The fabricated FTO in the present work is promising for further development as conducting glass for dye-sensitized solar cell (DSSC)."

"This study aimed to determine the effect of using acrylonitrile butadiene styrene in place of conventional wax material on treatment pattern removal in the investment casting process. There are three controllable process variables that can affect treatment pattern removal, which include temperature increase, holding time and the number of layers of ceramic shell that have been considered for comparison. Comparison among the effects of temperature increase, holding time and numbers of ceramic shell layers on the ceramic shell was analyzed using ANOVA. It was found that temperature increase (Tx), holding time (t) and number of layers of ceramic shell (N) contribute significantly to the length of the crack (l) on the ceramic shell. The crack in the ceramic shell?s surface was analyzed using scanning electron microscope photos. Less layers number cause the increase of crack length. The combination between temperature upraise and longer holding time cause cracking delay. The experimental is conducted by using 3 (three) variants for each of layers number, temperature and holding time. The layers number is ranging between 7-9 layers. Temperature increase from room temperature until 1300oC. The layers number variant is ranging between 180-300 seconds. It was concluded that a longer holding time will result in a more intact ceramic shell, as longer holding times yield short crack lengths."

"Transparent conductive oxide (TCO) glass is one of most important components in dye-sensitized solar cell (DSSC) device. In addition to its high electrical conductivity, transparency is another important requirement that must be achieved in fabricating TCO. One TCO film is fluorine-doped tin oxide (FTO), which can be considered as the most promising substitution for indium-doped tin oxide (ITO), since the latter is very expensive. However, the fabrication techniques for TCO film need to be carefully selected; the synthesis parameters must be properly optimized to provide the desired properties. In this work, FTO glass has been fabricated by the ultrasonic spray pyrolisis technique with different precursors, i.e. tin (II) chloride dihydrate (SnCl2.2H2O) and anhydrous tin (IV) chloride (SnCl4), as well as different solvents, i.e. ethanol and methanol. For both conditions, ammonium fluoride (NH4F) was used as the doping compound. The resulting thin films were characterized by use of a scanning electron microscope (SEM), x-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectroscopy and a four-point probe test. The results of the investigation show that the highest transmittance of 88.3% and the lowest electrical resistivity of 8.44×10-5 ?.cm were obtained with the FTO glass processed with 20 minutes of spray pyrolysis deposition and 300oC substrate heating, using SnCl4 as the precursor and methanol as the solvent. It can be concluded that TCO fabrication with tin chloride precursors and ammonium fluoride doping using ultrasonic spray pyrolisis can be considered as a simple and low cost method, as well as a breakthrough in manufacturing conductive and transparent glass."

"ABSTRAKKaca konduktor memiliki fungsi strategis di berbagai aplikasi elektronik. Jenisyang menjanjikan adalah Fluorine-doped Tin Oxide (FTO). Dalam penelitian inidilakukan studi pengaruh waktu deposisi (5, 10, 20, 30, dan 40 menit) lapisan tipisFTO dengan metode spray pyrolysis menggunakan alat ultrasonic nebulizer yangtelah dimodifikasi terhadap nilai karakteristik lapisannya ditinjau dari sifat optis,kristalinitas, resistivitas, dan mikrostruktur. Variasi juga dilakukan denganmembandingkan prekursor Sn murni dan larutan yang telah didoping dengan Fsebanyak 2%wt untuk melihat pengaruh penambahan doping F pada larutanprekursor. Pengujian karakteristik lapisan dilakukan menggunakan XRD, SEM,UV-Vis spectroscopy, dan digital multimeter. Berdasarkan karakterisasi yangdilakukan diperoleh nilai terbaik untuk FTO yang dihasilkan adalah pada waktudeposisi 20 menit dengan nilai transmitansi 74%, energi band gap (Eg) 3,85 eV,dan sheet resistance (Rs) 7,99 Ω/sq.

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ABSTRACTConductive glass has strategic functions in various electronic applications. Oneof the lead is Fluorine-doped Tin Oxide (FTO). In this research, the effects ofdeposition time (5,10,20,30, and 40 minutes) for fabrication of FTO thin film uponspray pyrolysis process using modified ultrasonic nebulizer on its characteristicin terms of optical, crystalinity, resistivity and microstructure properties has beenstudied. Variation was also performed by comparing the pure Sn precursor andthe solution that has been doped with F 2%wt to see the doping effect toproperties of thin film. The thin film characterization were carried out using XRD,SEM, UV-Vis spectroscopy, and digital mutlimeter. Based on the results obtainedfor the best FTO was generated at the time of deposition is 20 minutes. Providing74% transmittance, band gap energy (Eg) 3.85 eV and sheet resistance (Rs) 7.99Ω/sq."

"In 2016, the mandatory use of biodiesel as a substitute fuel by up to 20%,as introduced by the Indonesian Ministry of Energy and Mineral Resources,forced vehicle manufacturers to invent suitable engines that would acceptbiodiesel. The use of biodiesel in such a large proportion is highly risky,particularly due to the formation of deposits in the combustion chamberengines. The previous method of fuel droplets are placed on a hot plateapproach produces deposits are slightly different from those generated by areal engine, therefore to obtain realistic deposits it is necessary to modifythis method so temperatures as hot as those in a real engine. In this study,the potential deposit formation of biodiesel fuel was examined by conductingthe deposition process and the evaporation of fuel on a stainless-steel plate(SS), which was placed in a closed space. Deposit characterization was carried outon a hot plate using Scanning Electron Microscopy (SEM). The test results showeddifferences in the structures of the deposits produced by biodiesel and dieselfuel; fine structures were seen in the former, while those of the latter wererougher and more porous. Deposit results that are similar to what is seen in areal engine will be very helpful for knowing the patterns, structures, and mechanismof the formation of deposits in such an environment."

"The Aluminum 7075 (Al 7075) alloy is a precipitation hardening material instead of a strain hardening material. These mechanical properties are of a particular microstructure obtained by thermo-mechanical treatments. Among other things, this is a complicated microstructure which is responsible for the mechanical performance. The evolution of the mechanical properties of aluminum alloys is dependent on aging time parameters after heat treatment. In this study, the material has undergone a tempering heat treatment followed by a series of tensile tests. The experimental data (tensile curves in three directions during maturation time) is used to describe the evolution of the mechanical characteristics in terms of loading directions and maturation time, denoted respectively as: Ψ and t. The tensile curves are the source of data to begin the problem of identifying the behavior law of studied material using Barlat?s model and Hollomon?s isotropic hardening law. Thus, from the identified parameters (anisotropy coefficients and hardening coefficients), the evolution of the Lankford coefficient, deformation rate and load surfaces during the maturation time for three load directions (0°: rolling direction, 45° and 90°) are described. This study allows optimizing the response of the aluminum alloy to plastic strains, resulting from forming processes measured against the best time during maturation and the best load direction."

"Research and development activities on Liquefied Petroleum Gas (LPG) vehicles have increased LPG engine performance to that of gasoline engines. LPG evaporation in the fuel system also has a potential cooling effect that can be taken advantage of. The results from previous studies, however, do not explain the level of fuel in the tank at the time of data collection. LPG is a mixture of several molecules which have different properties. This paper presents an investigation of LPG composition characteristics in the fuel line during the discharging process. Samples were taken periodically on the fuel line by special gas syringes. Afterwards, the samples were injected into the Gas Chromatography-Mass Spectrometry (GC-MS) device. This series of tests, which was conducted on lengthy LPG tanks, showed that the propane and butane 2-methyl molecules are unevenly dispersed during the discharging of the tank. However, this study found that a change in LPG composition during the discharging process does not have significant influence on the energy delivery and the potential cooling effect."