• Journal of Auto-vehicle Safety Association
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• v.13 no.2
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• pp.30-34
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• 2021

Electrical failures and reliability problems of electronic components by ionic migration between adjacent device terminals have become an issue in automotive electronics. Especially unlike galvanic corrosion, ionic migration is occurred at high temperature and high humidity under applied electric field condition. Until now, although extensive studies of the ionic migrations dealing with PCBs, electrodes, and solders were reported, there is no study on the effect of insulation polymers and metallic fillers for ionic migration. In this research, therefore, ionic migration induced by the types and contents of polymers and metallic fillers, and variety conditions of temperature, humidity, and applied voltage was studied in detail. Ester and amide types of liquid crystal polymer (LCP) and poly (phthalamide) (PPA) were used as base polymers, respectively and compounded with the metallic fillers of Copper iodide (CuI), Zinc stearate (Zn-st), or Calcium stearate (Ca-st) in various compositions. The compounding polymers were fabricated in IPC-B-24 of SIR test coupon according to ISO 9455-17 with Cu electrodes for ionic migration test. While there is no change in LCP-based samples, ionic migration in PPA compounding sample with a high water absorption property was accelerated in the presence of 0.25 wt% or above of CuI at the environmental conditions of 85℃, 85% RH and 48V. The dendritic short-circuit growth of Cu caused by ionic migration between the electrodes on the surface of compounded polymers was systematically observed and analyzed by using optical microscopy and SEM (EDX).

• Journal of the Korean Chemical Society
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• v.28 no.2
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• pp.86-94
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• 1984

The single crystal ion-selective electrode,$ {\beta}-Ag_3SI/PVC-THF $membrane electrode has showed a linear potential response to the activities of iodide ion (10-1${\sim}$10-7M). The $ {\beta}-Ag_3SI$ membrane electrode was compared with AgI/PVC-THF membrane and copper metal plate membrane electrodes. In order to measure the selectivity coefficient of the electrodes toward $Cl^-$ and $Br^-$, the separation and mixed solution method were employed. The potential-time curve was obtained by the usual immersion technique and pH effect was also examined. The orders of selectivity for $Br^-$, $Cl^-$ and stability of response time are ${\beta}-Ag_3SI/PVC-THF $membrane > AgI/PVC-THF membrane > copper metal plate membrane. These electrodes could be used as indicating electrodes in the potentiometric titration of a single halide and mixed halides with the standard solution of silver nitrate.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.645-652
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• 1997

Electrochemical characteristics and kinetic parameters of copper ion reduction were investigated with a platinum rotating disk electrode (RDE) in a diffusion controlled region. Reduction of Cu(II) in sulfate had one-step two-xelectron process, while the reduction of Cu(II) in chloride solution was involved two one-electron processes. The transfer coefficient of Cu(II) in sulfate solution was lowest, and the transfer coefficient of Cu(I) in halide solutions had the value of nearly one. In chloride solutions, electrodeposition rate of Cu(II) was about one hundred times faster than Cu(I). Diffusion coefficient increased in the order of Cu(II) in chloride solution, Cu(I) in the iodide, bromide, chloride solution, Cu(II) in sulfate solution. The calculated ionic radii and activation energy for diffusion decreased in the same order as above. Morphological study on the copper electrodeposition indicated that the electrode surface became rougher as both concentration and reduction potential increases, and the roughness of the surface was analyzed with UV/VIS spectrophotometer.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.4 no.2
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• pp.45-50
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• 2018

Great efforts are currently devoted to the development of new approaches for the labeling of cells using appropriate radionuclides. While fluoride-18 and copper-64 have been extensively studied as short-term and intermediate-term trafficking agents, iodide was studied less intensely. Here, we report a new cell labeling agent labeled with $^{131}I$, $[^{131}I]$oleyl-4-iodobenzoate ($[^{131}I]$OIB) for long-term cell trafficking. A precursor of $[^{131}I]$OIB was obtained in two steps, with the yield of 35%. The radiochemical yield of $[^{131}I]$OIB was over 50%. While $[^{131}I]$OIB could label different cells, L6 cells showed the highest cell-labeling efficiency. The $[^{131}I]$OIB-labeled L6 cells were imprinted into a rat heart, and then monitored noninvasively for 2 weeks by gamma camera imaging. We conclude that $[^{131}I]$OIB is a good candidate molecule for a long-term cell trafficking agent.

• Journal of the Korean Chemical Society
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• v.67 no.6
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• pp.429-440
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• 2023

1,1-Dialkyl-2,5-bis(trimethylsilylethynyl)-3,4-diphenylsiloles (R=Et, i-Pr, n-Hex; 3a-c) were prepared and utilized as anode active materials for lithium-ion batteries; 3a was also used as a filler for the solid-state electrolytes (SSE). Siloles 3a-c were prepared by substitution reactions in which the two bromine groups of 1,1-dialkyl-2,5-dibromo-3,4-diphe- nylsiloles, used as precursors, were substituted with trimethylsilylacetylene in the presence of palladium chloride, copper iodide, and triphenylphosphine in diisopropylamine. Among siloles 3a-c, 3a had the best electrochemical properties as an anode material for lithium-ion batteries, including an initial capacity of 758 mAhg^-1 (0.1 A/g), which was reduced to 547 mAhg^-1 and then increased to 1,225 mAhg^-1 at 500 cycles. A 3a-composite polymer electrolyte (3a-CPE) was prepared using silole 3a as an additive at concentrations of 1, 2, 3, and 4 wt.%. The 2 wt.% 3a-CPE composite afforded an excellent ionic conductivity of 1.09 × 10^-3 Scm^-1 at 60℃, indicating that silole 3a has potential applicability as an anode active material for lithium-ion batteries, and can also be used as an additive for the SSE of lithium-ion batteries.

• Current Photovoltaic Research
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• v.11 no.2
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• pp.39-43
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• 2023

Carrier-selective contacts (CSCs) solar cells are considerably attractive on highly efficient crystalline silicon heterojunction (SHJ) solar cells due to their advantages of high thermal tolerance and the simple fabrication process. CSCs solar cells require a hole selective contact (HSC) layer that selectively collects only holes. In order to selectively collect holes, it must have a work function characteristic of 5.0 eV or more when contacted with n-type Si. The VO_x, NiO_x, and CuI_x thin films were fabricated and analyzed respectively to confirm their potential usage as a hole-selective contact (HSC) layer. All thin films showed characteristics of band-gap engergy > 3.0 eV, work function > 5.0 eV and minority carrier lifetime > 1.5 ms.

• Journal of Korean Society of Forest Science
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• v.67 no.1
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• pp.42-49
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• 1984

The elderberry was known to the ancients for its medicinal properties, and in Europe the inner back was formerly administered as a cathartic. The flowers contain a voletile oil, and serve for the distilation of elder-lower water, used in confectionery, perfumes and lotions. The leaves are employed to impart a green colour to fat and oil, and the leaves and bark emit a sickly odour, believed to be repugnant to insect. With its unique flavor and natural food colour, commercial processing companies used the fruit mainly in the making for jam, jelly, pies, juice, and wines. Its vitamin-C content is reported by Andross (1941) as 25-30mg/100g. Harvesting and processing have been mechanized to some extent. However, the cotains with nutritional value has not been reported yet. In the present study the various contains with nutritional value in the fresh elderberry juice is reported by the quantitative analysis. In this study results obtained can be summarized as follows. 1) The fresh elderberry juice contained following mineral elements; calcium 0.012%, magnesium 0.023%, potassium 0.10%, sodium 0.0019%, iron 0.0009%, cobalt 0.0002%, zinc 0.0004%, copper 0.0001%, phosphorus 0.036%, manganese 0.0006%, iodide $1{\mu}g/g$. 2) Five kinds of vitamines were also found ; vitamin-$B_1$ $0.1{\mu}g/g$, vitamin-$B_2$ $0.5{\mu}g/g$, vitamin-C 0.3mg/g, niacin $14{\mu}g/g$, choline chloride 0.3mg/g. 3) Fresh elderberry juice also contains crude protein 1.10%, fat 0.26%, carbohydrate 6.9%, pectin 0.76%, tannin 0.89%, ash 0.80%, water 90.9% and 34.3 cal/100g. 4) The absorption spectrum of the purplishblack color of fresh elderberry juice has a peak between 523-530mm.