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[en] A route to obtain nano-sized IZTO (Indium Zinc Tin Oxide) materials with relatively low indium content is investigated using an RF (Radio-Frequency) thermal plasma system. For this purpose, In2O3, SnO2 and ZnO with the sizes of 0.1–1 μm were mixed at the cation ratios of 6:2:2 and 2:1:1, and then, injected into RF thermal plasma with a plate power level of ∼ 26.6 kVA. From the field emission scanning electron microscopy images and the transmission electron microscopy–electron energy loss spectroscopy mapping images of the as-synthesized powders, it was found that the three oxides were unified into nano-sized IZTO particles (< 50 nm), with each element of In, Zn and Sn uniformly distributed. In addition, X-ray diffraction data and inductively coupled plasma-optical emission spectrometry analysis results showed that the IZTO powders with a single phase of bixbyite In2O3 structure can be achieved even with an indium content of 60 at.%.
[en] It is known that any loose part in the reactor coolant system (RCS) brings serious damage into the system components and impede the normal function of the system. In this paper, we applied the automatic diagnosis estimation algorithm to the impact test data of Kori-4 and UCN 3 and 4. The impact point estimated by the developed algorithm has about 30% average error rate at UCN 3 and about 17.47% at UCN 4. Also, the result showed that average mass estimation error of this algorithm has within 71.9%(100 gram) and 47.107%(200 gram) at Kori-4
[en] A simple method was developed for the analysis of seven stilbene-type fluorescent whitening agents (FWAs) in paper materials by ion-pair reversed-phase high-performance liquid chromatography with fluorescence detection. These stilbene-type FWAs included two disulfonate, two tetrasulfonate, and three hexasulfonate compounds. After optimization of chromatographic conditions, the FWAs were satisfactorily separated using a reversed-phase column (RP-18) with the following isocratic mobile phase: methanol-water (60:40) containing 17.5 mM TBABr and 10 mM citrate buffer (pH = 7.0). The calibration plot was linear in the range from 5 to 500 ng/mL for two disulfo-FWAs and from 1 to 500 ng/mL for the other five FWAs. Precision levels of the calibration curve as indicated by RSD of response factors were 1.2 and 8.1%. Limits of quantitation (LOQ) ranged from 1.2 to 11 ng/mL
[en] An experimental study was conducted to scrutinize the influence of the frequency of an ultrasonic standing wave on the variation in the behavior of a methane-air premixed flame. The evolutionary features of the propagating flame were captured by a high-speed camera, and the macroscopic flame behavior, including the flame structure and local velocities, was investigated in detail using a post-processing analysis of the high-speed images. It was found that a structural variation and propagation-velocity augmentation of the methane-air premixed flame were caused by the intervention of the ultrasonic standing wave, which enhanced the combustion reaction. Conclusive evidence for the dependency of the flame behaviors on the driving frequency of the ultrasonic standing wave and equivalence ratio of the reactants is presented
[en] We report here on two cases of ruptured epidermal inclusion cysts in the subareolar area, which is a very unusual location for these cysts and these lesions can be mistaken for breast malignancies. Although the epidermal inclusion cyst is an uncommon finding in the breast, we can easily diagnosis this as a cyst. But when it is presented in an unusual subareolar location and with a ruptured state, it can be mistaken for breast malignancy. We present here two surgically confirmed cases of ruptured epidermal inclusion cyst in a subareolar location, and this has not been previously described in the English medical literature. In our cases, we first considered the possibility of breast malignancy because the masses presented as an irregular mass on the initial sonography, and the patients were over the age 40 and we didn't take the possibility of abscess from ruptured epidermal inclusion cyst into consideration due to its rare occurrence and the unusual lesion location. FNAB and follow up imaging study after medical treatment, or the recurrent feature were the ways to later narrow the differential diagnosis. In conclusion, when a subareolar lesion has findings on sonography that are suspicious of malignancy, the differential diagnosis should include a ruptured epidermal inclusion cyst, with or without evidence of inflammation
[en] The compressible flow field is numerically analyzed in a two-dimensional converging-diverging nozzle of which the area ratio, exit to throat, is 1.8. The solver is FLUENT and the embedded RNG k -ε model is adopted to simulate turbulent flow. The plume characteristics such as shock-cell structure are discussed when nozzle pressure ratio and stagnation temperature at the nozzle entrance are varied. The downstream flow field can be classified into two types based on the shock shapes generated near the nozzle exit. First, a reiterative pattern in the plume is not formed between the slip streams in case that a strong lambda-type shock wave exists. Second, when oblique shock waves are crossing each other on the nozzle centerline, a shock cell structure appears in the plume field. Even when the flow field is changed due to stagnation temperature, the upstream of the shock wave is little affected. Especially, the pressure distributions on the nozzle centerline behind the shock wave are rarely influenced by the stagnation temperature, that is, the product of density and temperature is nearly constant provided that the working fluid is a perfect gas. Therefore, the pressure field shows quasi-isobaric behavior far downstream
[en] Several PVDF-HFP/silylated γ-AI2O3-coated PE (polyethylene) separators with various solidities (various compositions of PVDF-HFP/silylated γ-AI2O3) were prepared by a dip-coating of PE separators in PVDF-HFP/silylated γ-AI2O3/acetone mixtures. FT-IR spectroscopy was used to confirm the chemical reactions between silane coupling agent and γ-AI2O3. The SEM images of the coated separators showed that various morphologies could be produced by changing the composition of total contents of binder and solid contents. The effects of composition in inorganic material (silane coupling agent-treated γ-AI2O3) and binder (PVDF-HFP) on the physio-chemical properties of the prepared separators such as liquid electrolyte uptake, and ion conductivity were investigated and reported in this paper
[en] In this study, finite element analysis of beam on elastic foundation, which received great attention of researchers due to its wide applications in engineering, is performed for estimating dynamic responses of shallow foundation using exact stiffness matrix. First, element stiffness matrix based on the closed solution of beam on elastic foundation is derived. Then, we performed static finite element analysis included exact stiffness matrix numerically, comparing results from the analysis with some exact analysis solutions well known for verification. Finally, dynamic finite element analysis is performed for a shallow foundation structure under rectangular pulse loading using trapezoidal method. The dynamic analysis results exist in the reasonable range comparing solution of single degree of freedom problem under a similar condition. The results show that finite element analysis using exact stiffness matrix is evaluated as a good tool of estimating the dynamic response of structures on elastic foundation.
[en] Modern radiation therapy technique such as IGRT has become a routine clinical practice on LINAC for decrease patient's set-up error. CBCT can be used to adjust patient set-up error and treat patient more accurately. The purpose of this study is to evaluate field size of CBCT for improving Image quality and suggest reference date of CBCT field size. Materials and Methods: Image date were acquired using KV CBCT and Catphan phantom (Half fan and full fan mode were scanned from 2 - 16 cm, at intervals of 2 cm). Field size were categorized by Small field size (2 cm, 4 cm), Medium field size (8 cm, 10 cm), Large field size (more than 14 cm) and evaluate. To estimated the CTDi using CTDi phantom and Ion chamber. Results: CT number linearity of Small and Large field size are greater than Medium field size. Spatial resolution are not significantly different without Small field size. But half fan mode is more different than full fan mode. In full fan, except Medium field size, all field size exceed recommendation for HU uniformity. But half pan has stability for all field except Small field size. CTDi makes radical sign function graph in Medium field size. The worst result was given by Small field size for Image quality and practically. Medium field size can be useful to prevent patient from radiation exposure and give better Image quality. So this study recommends that Medium field size (8-10 cm) is more suitable for CBCT
[en] This experimental study scrutinizes the structural variation of a premixed propane-air flame according to the frequency change of ultrasonic standing waves (USWs) at various equivalence ratios. Visualization technique via Schlieren photography is employed in the observation of the flame structure and in the analysis of the flame velocities along the propagation. A distorted flame front and horizontal splitting in the burnt zone result from the USW. The vertical locations of the distortion and horizontal stripes are closely dependent on the frequency of the USW. In addition, the propagation velocity of the flame front floored by the standing wave is greater than that in the case without the excitation by the standing wave. As expected, the influence of the USW on the premixed-flame propagation becomes prominent as the frequency increases. The results suggest that a well-defined USW may be applied to combustion devices, such as gas turbines and chemical rocket engines, to achieve an active control of the instability that frequently intervenes in such systems.