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[en] Nickel sulfide (NiS) as a cathode material for a lithium rechargeable battery was charged and discharged at elevated temperature (80 deg. C) using a PEO solid polymer electrolyte. In order to synthesize a homogeneous NiS phase, very fine nickel metal powder was ball milled with sulfur powder for 12 h under argon gas. We found using ex-situ XRD measurements that the NiS cathode active material was transformed into other phases such as Ni3S2, nickel and sulfur during discharge. The initial discharge capacity of the NiS positive electrode was 580 mAh/g NiS at 1.5 V vs. Li/Li+ with PEO electrolyte. It has good cycling properties, retaining 93% of the initial discharge capacity even after 200 cycles with a PEO solid polymer electrolyte
[en] Recent reports suggest that beta-amiroid peptides are a major factor in Alzheimer's disease. Early diagnosis of beta amyloid plaques is very important for the diagnosis and treatment of diseases. In this study, we developed the synthesis technology of near-infrared fluorescent compound that can detect Aβ, one of the main causes of AD, and the real-time detection imaging technology of mouse Aβ. Four novel synthetic compounds were confirmed to have the same structure as the technology transfer compound through 1H-NMR and NRMS analysis. HPLC, UV-Vis spectrophotometer and PL spectrometer, in vivo and ex vivo imaging analysis of four new synthetic compounds showed superior performance compared to competing products and technology transfer compounds. Synthesis and industrial preparation of near-infrared fluorescent compounds for the detection of Aβ-Aβ were established, and its purpose is to commercialize near-infrared fluorescent imaging probes for Aβ small animal imaging. R & D achievements include: 1) Technology transfer of near-infrared fluorescent compound that can detect Aβ, one of the main causes of AD, and Aβ real-time detection imaging technology of mouse using it; 2) Four new synthetic compounds 1H-NMR, NRMS analysis confirmed the same structure as the previous technology, 3) Competitive products and technologies through HPLC, UV-Vis spectrophotometer and PL spectrometer, in vivo and ex vivo imaging analysis of four new synthetic compounds 4) the synthesis and industrial preparation of near-infrared fluorescent compounds for the detection of Aβ were established. The expectation of this study is to commercialize Alzheimer's imaging near-infrared fluorescence probe using domestic technology.
[en] The electronic structures, the magnetic moments and the optical conductivity spectra of the Co1-xAlx (x=0.5, 0.4375, and 0.375) alloys were calculated using the tight-binding linearized-muffin-tin-orbital method. The supercell method was employed to calculate the properties of the alloys with the off-stoichiometric concentrations. The calculated magnetic moments were in reasonable agreement with the experimental results. The inclusion of corrections for both the real and the imaginary parts of the self-energy markedly improved the agreement between the experimental and calculated the optical conductivity spectra
[en] This paper has investigated a method of fabricating large-grained UO2 pellets without impurity additives. A specially prepared U3O8 powder- U3O8 seeds was added to UO2 powder and then mixed. The mixed powder was processed to fabricate large-grained UO2 pellets according to the conventional pressing and sintering method. The U3O8 seed was made from UO2 pellet scrap. It was oxidized at 400-500 deg in air to produce fine U3O8 powder and then heat-treated at 800-1500 deg in air to form coarse U3O8 particles. A heat-treated particle consisted of many well-developed crystals bonding partly each other. Dividing this poly-crystalline particle into individual crystals produced single-crystal particles (U3O8 seeds). Seeds having different sizes were added in various quantities to the UO2 powder, and seeded UO2 pellets were fabricated. When the U3O8 seed of about 5-size was added in a quantity of 4 wt.%, the grain size increased from 8 to 20. The U3O8 seed might act as a promoter for grain growth in UO2 sintering
[en] The structural dependences of the galvanomagnetic properties of Co-Al and Fe-Al alloy films were investigated in this study. Ordered and disordered alloy films with thickness of 150 nm were prepared by using the flash evaporation technique on the heated and cooled substrates, respectively. The temperature dependence of resistance was measured in the range of 2 ∼ 300 K range with and without a magnetic field of 0.5 T. The influence of the order-disorder structural transition on the temperature dependence of the resistance is discussed in connection with the results for the magnetic properties and is analyzed in the framework of the partial localization of the electronic states and variable-range hopping conductivity
[en] This study is to minimize the patient dose and maintain the image quality according to change of source to image receptor distance and applying additional filter. In this study, we used the DR system, the tissue-equivalent abdomen phantom and the aluminium filter. The exposure conditions were set to 80 kVp using AEC mode. The collimation size was 16 x 16 inch. The exposure dose were measured 10 times when the SID was changed with 100, 110, 120 and 130 cm, respectively. The pirana 657 for dosimeter was located on center of radiation irradiation. The acquired images were analyzed by using the image J. In the results, the tube current was increased with increasing the SID but ESD was decreased with increasing the SID. The decrease of ESD attribute to use of filter that remove the photon of lower energy. In the histogram results using image J, there were differences between the ESD and the exposure conditions according to change of SID. However, there were not differences in histogram. Therefore, the exposure dose could reduced when set the longer SID. For pediatric exam, the exposure dose could reduced when used the aluminium filter
[en] Silica-manganese oxides with a core-shell structure were synthesized via precipitation of manganese oxides on the SiO2 core while varying the concentration of a precipitation agent. Elemental analysis, crystalline property investigation, and morphology observations using low- and high-resolution electron microscopes were applied to the synthesized silica-manganese oxides with the core-shell structure. As the concentration of the precipitating agent increased, the manganese oxide shells around the SiO2 core sequentially appeared as Mn3O4 particles, Mn2O3+Mn3O4 thin layers, and α-MnO2 urchin-like phases. The prepared samples were assembled as electrodes in a supercapacitor with 0.1 M Na2SO4 electrolyte, and their electrochemical properties were examined using cyclic voltammetry and charge-discharge cycling. The maximum specific capacitance obtained was 197 F g-1 for the SiO2-MnO2 electrode due to the higher electronic conductivity of the MnO2 shell compared to those of the Mn2O3 and Mn3O4 phases
[en] Recently, There has been a growing interests in exposure dose to the patient who take a examination using radiation. The radiological technologists should be concerned about the exposure dose to patients and make an efforts to reduce the patient dose without decreasing the image quality. In the case of foreign, the exposure dose of general X-ray examination have been managed by standard value of exposure dose using dose area product (DAP) and entrance surface dose (ESD) dosimeter. This study is to compare DAP and ESD in skull anterior posterior (AP), chest posterior anterior (PA), and abdomen AP projections of phantom by using DAP and ESD dosimeter. In the results, there were no differences between DAP and ESD dosimeter
[en] Polycrystalline Cu-doped ZnO films have been successfully fabricated, and room-temperature ferromagnetism (RTFM) has been achieved. Sputtering of a Cu-chip-embedded ZnO target enabled a low-doping concentration of Cu. RTFM was obtained for the entire substrate temperature range from RT to 300 .deg. C. However, the best result was obtained at a substrate temperature of 100 .deg. C, and the magnetic properties of the Cu-doped ZnO films turned out to be very sensitive to the crystalline structure.
[en] In this work, we investigate the growth behavior of silicon oxide nanowires via a solid-liquid-solid process. Silicon oxide nanowires were synthesized at 1000 .deg. C in an Ar and H2 mixed gas. A pre-oxidized silicon wafer and a nickel film are used as the substrate and catalyst, respectively. We propose two distinctive growth modes for the silicon oxide nanowires that both act as a unique solid-liquid-solid growth process. We named the two growth mechanisms 'grounded-growth' and 'branched-growth' modes to characterize their unique solidliquid- solid growth behavior. The two growth modes were classified by the generation site of the nanowires. The grounded-growth mode in which the grown nanowires are generated from the substrate and the branched growth mode where the nanowires are grown from the side of the previously grown nanowires or at the metal catalyst drop attached at the tip of the nanowire stem