• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.71-74
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• 1965

Reduction of Ti(Ⅳ)-oxalate complex on dropping mercury electrode has been studied as a function of oxalate concentration and of pH varied with HCl. Assuming there are equilibrium $TiO(C_2O_4)_2= \;+\;2H^+\;=\;Ti^{+4}\;+\;2C_2O_4\;=\;+\;H_2O,\;K_4$ in addition to $TiO(C_2O_4)_2\;^=\;=\;TiO^{++}\;+\;2C_2O_4=\;K_2\;Ti(C_2O_4)_2\;^-\;=\;Ti^{+3}\;+\;2C_2O_4=\;K_3$ in the system cathodic wave has been well explained for that pH is higher than 0.5. The equilibrium constants $K_2,\;K_3$ and $K_4$ have been to be $2{\times}10^{-12},\;5{\times}10^{-13}$ and $10^{-11}$, respectively. The reduction of Ti(Ⅳ)-oxalate system is $Ti^{+4}\;+\;e\;{\to}\;Ti^{+3}$ in the concentration of hydrochloric acid, higher than 3M.

• Journal of IKEEE
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• v.27 no.4
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• pp.630-635
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• 2023

SiC is replacing the position of silicon in the power semiconductor field due to its superior resistance to adverse conditions such as high temperature and high voltage compared to silicon, which occupies the majority of existing industrial fields. In this paper, the gate of 4H-SiC Planar MOSFET, one of the power semiconductor devices, was formed with aluminium to make the contrast and parameter values consistent with polycrystalline Si gate, and the threshold voltage, breakdown voltage, and IV characteristics were studied by varying the channel doping concentration of SiC MOSFET.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.986-990
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• 2004

Condensation of salicylaldehyde $(2-HOC_6H_4C(O)H)$ with allylamine afforded the unsaturated salicylaldimine, $2-HOC_6H_4C(H)=NCH_2CH=CH_2$. Similar reactivity was observed with substituted salicylaldehydes. Further reaction of these Schiff bases with palladium acetate or $Na_2PdCl_4$ afforded complexes of the type $PdL_2$, where L = deprotonated Schiff base. The molecular structure of the parent salicylaldimine palladium complex $[trans-(2-OC_6H_4C(H)=NCH_2CH=CH_2)_2Pd]$ (1) was characterized by an X-ray diffraction study. Crystals of 1 were monoclinic, space group $P2_1/n,\;a\;=\;14.0005(9)\;{\AA},\;b\;=7.2964(5)\;{\AA},\;c\;=\;17.5103(12)\;{\AA},\;{\beta}\;=\;100.189(1)^{\circ}$, Z = 4. Analogous chemistry with 4-vinylaniline also gave novel palladium complexes containing a pendant styryl group. Crystals of $[trans-(2-HOC_6H_4C(H)=N-4-C_6H_4CH=CH_2)_2Pd]$ (4) were monoclinic, space group $P2_1/c$, a = 13.7710(14) ${\AA}$, b = 11.0348(11) ${\AA}$, c = 7.8192(8) ${\AA}$, ${\beta}\;=\;98.817(2)^{\circ}$, Z = 2.

• Environmental Mutagens and Carcinogens
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• v.17 no.1
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• pp.1-6
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• 1997

The RAD4 gene of Saccharomyces cerevisiae is essential for the incision step of UV-induced excision repair. A yeast RAD4 gene has been previously isolated by functional complementation. In order to identify the RAD4 homologous gene from fungus Coprinus cinereus, we have constructed cosmid libraries from electrophoretically separated chromosomes of the C. cinereus. The 13 C. cinereus chromosomes were resolved by pulse-field gel electrophoresis, hybridized with S. cerevisiae RAD4 DNA, and then isolated homologous C. cinereus chromosome. The insert DNA of the RAD4 homolog was contained 3.2 kb. Here, we report the partial cloning and characterization of fungus C. cinereus homolog of yeast RAD4 gene. Southern blot analysis confirmed that C. cinereus contains the sequence homologous DNA to RAD4 gene and this gene exists as a single copy in C. cinereus genome. When total RNA isolated from C. cinereus cells was hybridized with the 1.2 kb PvuII DNA fragment of the S. cerevisiae RAD4 gene, a 2.5 kb of transcript was detected. The level of the transcript did not increase upon UV-irradiation, suggesting that the RAD4 homologous gene in C. cinereus is not UV-inducible.

• Elastomers and Composites
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• v.59 no.1
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• pp.1-7
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• 2024

Nanorod graphitic carbon nitride (g-C₃N₄) was synthesized by reacting melamine (C₃H₆N₆) with trithiocyanuric acid (C₃H₃N₃S₃) in distilled water for 10 h at room temperature. The resulting mixture was calcined at 550℃ for 2 h in an electric furnace under an air atmosphere. Nanorod g-C₃N₄/Ag₃PO₄ composites were prepared by adding nanorod graphitic carbon nitride (g-C₃N₄) powder, silver nitrate (AgNO₃), ammonia (NH₃·H₂O, 25.0-30.0%), and sodium hydrogen phosphate (Na₃HPO₄) to distilled water. The samples were characterized via X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy. The photocatalytic activities of the nanorod g-C₃N₄/Ag₃PO₄ composites were demonstrated via the degradation of organic dyes, such as methylene blue and methyl orange, under blue light-emitting diode irradiation and evaluated using UV-vis spectrophotometry.

• Korean Journal of Materials Research
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• v.2 no.6
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• pp.461-467
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• 1992

A fabrication process for SiC whisker preform reinforced AC4A Al composites is being developed. The Al alloy used as the matrix in this study is AC4A. SiC whisker preform made by Tokai Carbon Co. Ltd. Shizuoka, Japan were used. These consisted of $\beta$-type single crystals 0.1 ~ 10${\mu}$m in diameter and 20~10${\mu}$m in length. The most adequate fabrication condition was that whisker preform was preheated up to 750~80$0^{\circ}C$, set into a mould preheated to ~40$0^{\circ}C$, molten Al alloy heated to ~80$0^{\circ}C$ and applied pressure 75MPa. And Si$C_w$reinforced AC4A composite was advanced above twice than AC4AI/M. Also it was not large effect by pressure at Si$C_w$ 20v/o.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.154-159
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• 2004

Bacillus species were isolated from swine manure to develope the microbial additive suitable for the rapid com-posting. The 3 of 4 isolated strains were identified as Bacillus cereus KD-2, B. pumilus KD-3, and B. licheni-formis KD-4. Bacillus sp. KD-1 was, however, not highly identical with any Bacillus sp. The isolated strains were analyzed their growth rates, enzyme activities, and antibacterial activities. The maximum growth tem-peratures of KD-1, KD-2, KD-3 and KD-4 were $45^{\circ}C$, $50^{\circ}C$, $53^{\circ}C$, and $55^{\circ}C$, respectively. The activities of pro-tease or amylase in mixed culture of 4 strains were similar in the range of $37^{\circ}C$ to $53^{\circ}C$ and activities of lipase in the range of $37^{\circ}C$ to $42^{\circ}C$ were twice higher than those of lipase in the range of $47^{\circ}C$ to $53^{\circ}C$. The antibacterial activity of KD-l, KD-2, or KD-3 against each other was not detected. That of KD-4 against KD-1, KD-2, or KD-3 was, however, detected. The organic compound and C/N ratio of compost fermented by the mixed culture were determined as 61.9% and 22.4%, respectively. The concentration of the ammonia gas was 12.35 mg/l in the liquid compost.

• Korean Journal of Plant Tissue Culture
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• v.28 no.5
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• pp.263-271
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• 2001

Inoculated anthers of Capsicum annuum L. were subjected to 4 and 32$^{\circ}C$ pretreatment and their influence on the microspore viability, early cytological changes and the induction frequency of microspore embryo was investigated. Viability of freshly isolated microspores was between 62 and 64%. During temperature pretreatment, microspore viability showed a rapid decrease and this tendency enhanced with the 32$^{\circ}C$ pretreatment. Irrespective of temperature pretreatment, microspore viability declined to nearly zero after nine days. Before temperature pretreatment, most of the microspores in anthers were at late uninucleate stage. Several types of multinuclear microspores appeared from the 2 day after culture onwards, together with many degenerated and non-induced microspores. The 32$^{\circ}C$ pretreatment gave higher proportions of embryogenic microspore than other treatment. However, the temperature pretreatment had no clear effect on the frequencies of symmetrical binucleate rnicrospore. The multinucleate grains might originate either by symmetrical or asymmetrical division. After 2 days of pretreatment at 25 and 32$^{\circ}C$ , degenerated microspore increased above 50%. In contrast, during 4$^{\circ}C$ treatment, nucleus of most microspores remained intact for 14 days. The 32$^{\circ}C$ pretreatment produced more embryos than 4$^{\circ}C$ treatment. The most effective period of 32$^{\circ}C$ pretreatment was 4 days. In contrast, effective period of 4$^{\circ}C$ pretreatment was 2 days and longer time had deleterious effect on induction of microspore embryo.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.67-74
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• 2012

A study was conducted to examine the effect of precooling and storage temperatures on the storage life of 'Maehyang' strawberry for export. Fruits at a 80% ripe stage were harvested from a commercial greenhouse in Gyeongsangnamdo Jinju on January 11, 2011. Fruits were precooled at 0, 2, $4^{\circ}C$ for 2-5 hours, and then transported for about 30 minutes. And stored in set chamber at 4, 8, $10^{\circ}C$, immediately. Fruits were examined for their changes in weight, hardness, Hunter color values, soluble solid content (SSC), acidity, and incidence of gray mold (Botrytis cinerea) during storage. The fresh weight decreased during storage at all temperatures. Especially, strawberry treated the lowest precooling and storage temperatures was the greatest in quality. The hardness was drastically decreased in precooled at $4^{\circ}C$ and stored at $10^{\circ}C$ after storage 10 days. SSC was the greatest when strawberry stored at the lowest temperature. Acidity increased during storage at all temperatures. But in the last day after storage, the strawberry of precooled at $4^{\circ}C$ and stored at $10^{\circ}C$ was the highest as 0.7%. Gray mold was the greatest at $10^{\circ}C$ storage temperature. The results indicate that effectiveness for keeping the freshness was best achieved by precooling at $0^{\circ}C$ and storage at $4^{\circ}C$.

• Journal of the Korean Society of Radiology
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• v.9 no.4
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• pp.197-203
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• 2015

The Study on the patient is in a clinical researcher is not necessarily pose before after before after dwichim (Pronation) pose with neck-in-law (RAO, LAO) to chwalyoungbeop subjective evaluation experiment looked at objectively. Overview evaluation is a result of measuring the angle of the space between the vertebrae in PACS image $C_2{\sim}C_3$, $C_3{\sim}C_4$, $C_4{\sim}C_5$, $C_5{\sim}C_6$, $C_6{\sim}C_7$, in the angle of the $C_7{\sim}T_1$ $47.4^{\circ}{\pm}3.3$, $50.5^{\circ}{\pm}2.3$, $52.7^{\circ}{\pm}4.2$, $53.2^{\circ}{\pm}1.9$, $53.2^{\circ}{\pm}2.3$, $55.2^{\circ}{\pm}2.3$ was found to show increasing the angle between the ball and the median nerve in the lower neck sagittal grows. In a comparison of the measured angles in foraminal image was not significantly different (P>0.01). Subjective evaluation Recever Operation characteristic to the top, the upper neck hole (foramen) C2 ~ C3-up than conventional $45^{\circ}$ angle of the lower neck, $C_3{\sim}C_4$, were observed in the well $50^{\circ}$ $C_5{\sim}C_6$, $C_6{\sim}C_7$, the $C_7{\sim}T_1$ was observed at $55^{\circ}$ well observed experimental results video recession neck vertebrae son-in-law, son-in-law taken place in an objective evaluation, subjective evaluation of the upper neck after case could be observed at $50^{\circ}$, well in the lower neck $55^{\circ}$.