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"Barium strontium titanate (BST) or Ba1-xSrxTiO3 with x=0-1 possesses superior dielectric properties, which are widely used in many applications like in communication technology, electronic instrumentations, and various electrical devices. In this paper, the characterization of the particle and crystallite size of Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) is described. A two-step refinement commenced: first by mechanical milling, and then a further refinement under ultrasonic irradiation in a high power sonicator was applied to Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) particles. The crystalline powders were obtained through mechanically alloyed standard research grade BaCO3, TiO2, and SrCO3 precursors in a planetary ball mill.The powders were first found heavily deformed after 60 hours of milling and then went through a sintering process at 1200°C for 4 hours to form multicrystallite particles. The presence of a single phase in the three samples was solidly confirmed in their respective X-ray diffraction (XRD) patterns. The changes of multicrystallite particles into monocrystallite particles were obtained only after crystalline powders were irradiated ultrasonically in a high power sonicator. The processing variable during ultrasonic irradiation was limited to the duration time of irradiation and particle concentration in the exposed media. It is shown that the average sizes of BST particles at x=0; 0.3; 0.7 before ultrasonic irradiation were 353, 348, and 385 nm, respectively. These respective sizes decreased drastically to 52, 35, and 49 nm, respectively, after 12 hours of ultrasonic irradiation. These particle sizes are almost identical with that of their crystallite size. Hence, the synthesis of monocrystallite particles has been achieved. As the particle concentration of media takes effect, it is shown that an exposed media with a higher particle concentration tends to form multicrystallite particles."

"Barium strontium titanate (BST) or Ba1-xSrxTiO3 with x=0-1 possesses superior dielectric properties, which are widely used in many applications like in communication technology, electronic instrumentations, and various electrical devices. In this paper, the characterization of the particle and crystallite size of Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) is described. A two-step refinement commenced: first by mechanical milling, and then a further refinement under ultrasonic irradiation in a high power sonicator was applied to Ba1-xSrxTiO3 (x: 0; 0.3; 0.7) particles. The crystalline powders were obtained through mechanically alloyed standard research grade BaCO3, TiO2, and SrCO3 precursors in a planetary ball mill.The powders were first found heavily deformed after 60 hours of milling and then went through a sintering process at 1200°C for 4 hours to form multicrystallite particles. The presence of a single phase in the three samples was solidly confirmed in their respective X-ray diffraction (XRD) patterns. The changes of multicrystallite particles into monocrystallite particles were obtained only after crystalline powders were irradiated ultrasonically in a high power sonicator. The processing variable during ultrasonic irradiation was limited to the duration time of irradiation and particle concentration in the exposed media. It is shown that the average sizes of BST particles at x=0; 0.3; 0.7 before ultrasonic irradiation were 353, 348, and 385 nm, respectively. These respective sizes decreased drastically to 52, 35, and 49 nm, respectively, after 12 hours of ultrasonic irradiation. These particle sizes are almost identical with that of their crystallite size. Hence, the synthesis of monocrystallite particles has been achieved. As the particle concentration of media takes effect, it is shown that an exposed media with a higher particle concentration tends to form multicrystallite particles."

"Nanostructured zincoxide (ZnO) was synthesized via a sonochemical method. The effect of the duration of ultrasonic irradiation in a continuous mode on the generated particles was investigated. Additionally, the effect of flowing either air or nitrogen during the sonication process was investigated. Zinc nitrate andammonia water-based solutions were selected as chemicals without the additionof other surfactants. The generated particles indicated that a wurtzitestructure of ZnO in a hexagonal phase was formed with a crystalline size that increasedas the ultrasound irradiation time increased. The morphology of the generatedZnO particles could be changed from flowerlike to needlelike structures viacontinuous ultrasound irradiation over one to two hours, resulting in increasesin the particle lengths and decreases in the particle diameters from 200 to 80nm. Photoluminescence intensity was also increased with increases in the ultrasonicirradiation times. Photoluminescence spectra were also influenced by theatmospheric environment. Two bands centered at 390 and 500 nm were generatedunder a nitrogen environment. On the other hand, a single wide band with a peakat around 430 nm was found for particles generated under an air environment. Itcan be applied for light emitting diodes (LED) or laser fabrication with acontrolled emitting band."

"Flotation is animportant process in mining industries. This process employs the bubble andhydrophobic properties of a particle to separate valuable mining particles fromimpurities. The most important phenomenon in determining flotation efficiencyis the bubble-particle interaction; therefore, understanding this phenomenon isvery important. The aim of this research is to study the mechanism ofbubble-particle interactions with and without the addition of a collector. Theexperimental setup consists of a water container, bubble generator, particlefeeding system, and an image capturing system. The water container is made fromtransparent material of a size large enough so that the wall?s effects onbubbles and particles can be neglected. Air bubbles are generated by a bubblegenerator which consists of a small nozzle and programmable syringe pump. Ahigh speed video camera and halogen lamp backlighting system are used as imagecapturing devices. Observation of the images reveals that bubble-particleinteraction follows the stages of bubble-particle collision, particle attachedto the bubble, and particle detached from the bubble. The addition of acollector to the liquid affects the bubble-particle interactions."

"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."

"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."

"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)."

"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."

"In recent times, thedemand for the real time audio and video applications in wireless networks isvery high due to widespread use of latest wireless communication technologies.Many of these applications require different Quality of Service (QoS) in termsof delay and throughput in the resource constrained wireless networks. In orderto handle the resources effectively and to increase the QoS, proper packetscheduling algorithms need to be developed. Low-latency Queuing (LLQ) is a packet scheduling algorithm whichcombines Strict Priority Queuing(SPQ) to Class-Based Weighted Fair Queuing (CB-WFQ). LLQ places delay sensitive applications suchas voice and video in the SPQ and treat them preferentially over other trafficby allowing the application to be processed and sent first from the SPQ. In this paper, an Enhanced LLQ (ELLQ) is proposed.An additional SPQ is introduced for scheduling the video applicationsseparately along with the dedicated SPQ for voice applications. The performanceof the proposed algorithm is compared with other existing algorithms throughsimulations using the OPNET modeler. Simulation and Statistical results showthat the proposed algorithm has given 1.5 times performance improvement interms of throughput and delay than the existing algorithms for the real timeaudio and video applications."

"The performance of a 20 MW gas turbine power plant was described by using the exergy analysis and data from the plant?s record books. The first and second laws of thermodynamics, as well as the mass and energy conservation law, were applied in each of the components. The results show that more exergy destruction occured in the combustion chamber up to 71.03% or 21.98 MW. Meanwhile, the lowest exergy occured in the compressor at 12.33% or 3.15 MW. Thermal efficiency of the gas turbine power plant, according to the first law, was 33.77%, and exergy efficiency was 32.25%."