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"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."

"Nanostructured zinc oxide (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 and ammonia water-based solutions were selected as chemicals without the addition of other surfactants. The generated particles indicated that a wurtzite structure of ZnO in a hexagonal phase was formed with a crystalline size that increased as the ultrasound irradiation time increased. The morphology of the generated ZnO particles could be changed from flowerlike to needlelike structures via continuous ultrasound irradiation over one to two hours, resulting in increases in the particle lengths and decreases in the particle diameters from 200 to 80 nm. Photoluminescence intensity was also increased with increases in the ultrasonic irradiation times. Photoluminescence spectra were also influenced by the atmospheric environment. Two bands centered at 390 and 500 nm were generated under a nitrogen environment. On the other hand, a single wide band with a peak at around 430 nm was found for particles generated under an air environment. It can be applied for light emitting diodes (LED) or laser fabrication with a controlled emitting band."

"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."

"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)."

"AbstrakTelah dilakukan pembuatan gel ceria stabilized zirconia (CSZ) dengan metoda gelasi eksternal. Sebagai bahan dasar umpan gelasi menggunakan Ce(NO3)3.6H2O dan ZrO(NO3)2.2H2O dengan perbandingan mol Zr/Ce = 8. Pembuatan umpan gelasi kedua bahan pokok dicampur dilarutkan dalam Air Bebas Mineral (ABM) ditambah zat aditif Polyvinyl Alcohol (PVA) sebagai pengatur viskositas dan Tetra Hydro Furfuryl Alcohol (THFA). Untuk memperoleh gel yang baik, maka parameter kunci yang harus dipenuhi antara lain pH sol, viskositas umpan, frekuensi, amplitude, dan flow rate aliran umpan. Proses setelah gelasi eksternal meliputi perendaman, pencucian, dan pengeringan, serta kalsinasi. Pada proses pencucian, konduktivitas air cucian terakhir dikondisikan pada ≤ 20 µS/cm setara dengan 0,001% berat kandungan NH4OH, dianggap gel sudah cukup baik untuk dilanjutkan ke proses selanjutnya. Proses pengeringan dilakukan pada kondisi vakum pada 80 C dan kondisi temparature kamar sedangkan kalsinasi pada suhu 300 C dan 500 C dengan lanju pemanasan ≤ 2ºC pada suasana atmosfer. Gel CSZ hasil pengeringan diukur diameternya dan kondisi fisiknya menggunakan mikroskop digital. Dari hasil pengukuran diameter gel CSZ basah, diameter gel hasil pengeringan adalah 1,0058 mm dan diameter hasil kalsinasi pada suhu 300ºC adalah 0,663 mm serta 500ºc diameternya adalah 0,635 mm. Kondisi fisik gel CSZ hasil pengeringan dan kalsinasi adalah utuh, bulat dan tidak pecah."

"Molecularly imprinted polymers (MIPs) have been the most convenient and selectedmethods in detection and extraction for many types of specific targets in various fields. MIPswere prepared by mixing template molecule with functional monomer in thepresence of cross-linker, solvent andinitiator. The selectivity of MIPs is strongly influenced by the types offunctional monomer, solvent and polymerization process used.Pyrogallol-imprinted polymer (Py-IP) and non-imprinted polymer (NIP) weresynthesized via precipitationpolymerization using 4-vinylpyridine (4-VP), divinylbenzene (DVB) andazobisisobutyronitrile (AIBN) as functional monomer, cross-linker andinitiator, respectively. Pyrogallol (Py) was used as a target molecule. Thesynthesized polymers were characterized by FourierTransform InfraredSpectroscopy (FTIR), Scanning Electron Microscopy (SEM), and UV-VisibleSpectroscopy (UV-Vis). In this study, adsorption capacity was measuredby the dosage effect, contact time and selectivity study. Results showed thatmaximum adsorption capacity by Py-IP is above 50%. The Selectivity study shows that k? is >1, which indicates that Py-IP has a good selectivity towards pyrogallol. Therefore, it has a goodpotential to be used as an adsorbent."

"Concreteis a favoured building material due to its ease of productionand use. Even though the concrete mix isdesigned to have a uniform strength throughout the entire member, casting, aswell as the basic characteristics of the concrete materials, could yield anon-homogeneous constitution, resulting in a concrete strength gradation as afunction of the depth of the member. A functionally continuous and smooth strengthgradation of the concrete member along its axis or section is defined as gradedconcrete. The objective of this researchis to analyse the influence of two different concrete compressivestrengths that composed the gradedconcrete member. Thestudy is split into two parts: theexperimental work describing and identifying the mechanical properties offunctionally graded concrete and the finite element analysis implementing theseproperty variations in a model. The results showed that the concrete gradationinfluenced the ultimate strength of a member negatively and altered the stressdistribution and displacement response of the specimen."

"The temperature and humidity inside poultry houses are highly coupled through nonlinear psychrometric processes, and the limitation of actuators makes this type of system difficult to control. To understand the dynamics of such systems and further to design a suitable controller, in this study, the mathematical model for a closed poultry house was derived from the governing equations of the various components related to the poultry house, including the energy and mass balance and the psychrometric correlations of the moist air. The model was simulated and the simulation result was compared to the data collected experimentally for model verification and control gains estimation. Under the assumptions of 70 percent Active Mixing Volume (AMV) with the constant maximum ventilation rate in the case study, the temperature and the relative humidity simulated results were in the good agreement with the real physical plant data. At the front, the middle and the rear part ofthe poultry house, the root-mean-square error (RMSE) obtained for internal temperatures are 1.17oC, 0.68oC, and 0.46oC, respectively. Andthose data for relative humidity are 4.31%, 8.07%, and 53.54%, respectively."

"The cloud is an outstandingplatform to deal with functionally equivalent services which are exponentiallyincreasing day-by-day. The selection of servicesto meet the client requirements is a subtle task. The services can be selected byranking all the candidate services using their network and non-network Quality-of-Service (QoS) parameters, which is formulated as a NP hard optimization problem. In this paper, weproposed a linear discriminant analysis (LDA) based a four level matching model for service selection based on QoS parameters,which includes description matching of a service, matchmaking phase, LDA-based QoS matching and ranking. The LDA-serviceselection agent is deployed on each cloud to classify services into classes andrank the services based on the aggregate QoS value of each service. Finally,the test results show the efficiency in service selection with minimaldiscovery overhead, significant reduction in the computation time and thenumber of candidate services to be considered."

"End-of-life Vehicle(ELV) recovery is a promising strategy to minimize the environmental impact ofautomotives on environmental sustainability. This study aims to assess thecommunity?s knowledge from a socio-technical perspective on ELV. A survey wasconducted in Japan and Malaysia to assess public perception on ELV recovery.The results showed that the communities in both countries have basic knowledgeand a reasonably good level of awareness on environmental issues and recoverystrategies such as recycling. However, there is a high level of uncertainty onthe concept of ELV reuse and remanufacturing, as more than 50% of respondentswere unsure of their willingness to participate in ELV initiatives. Therespondents agreed that the industry and government should take the necessarysteps to support the reuse strategy. The paper concludes with suggestions froma socio-technical perspective, which aim to ensure an effective implementationof ELV recovery through reuse and remanufacturing."