• Journal of Biosystems Engineering
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• v.20 no.2
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• pp.173-179
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• 1995

A modeling technique of land rearrangement was proposed using Geographical Information System(GIS) based on PC ARC/INFO. Three regions with different slopes were chosen. At first, slope angle and direction were calculated, and lands were rearranged using various parameters. The required parameters are obtained from PC ARC/INFO and the design factors for land rearrangement. The shape of land before rearrangement could be compared with the shape of land after rearrangement. Besides the shape comparison, drain site could be determined and the information for cost of land rearrangement could be obtained. The system was integrated on a menu driven style with SML files and subprograms. GIS was proved to be useful for land rearrangement design.

• Journal of Ginseng Research
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• v.17 no.3
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• pp.236-239
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• 1993

We studied the chloroplast rearrangement, short-term regulation depending on the light conditions in plants, and the characteristic of photosynthic rate as affected by in Panax ginseng C.A. Meyer. The chloroplast rearrangement of ginseng mesophyll cell was induced with the irradiation of blue light (400~500 nm) and through this process the rate of leaf transmittance increased 5~7.5%. The time to reach the maximum value of photosynthesis was shorter above 20 minutes with the blue light irradiation than that of the red light.

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1109-1112
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• 1998

An anchimeric assistance of anilide in the rearrangement of dichloro-1,4-oxathaines 1 to 2-chloromethyl dihydro-1,4-oxathiins 2 is described. The inductive effect of the carbonyl group of anilide was negligible in the rearrangement. A rate of the rearrangement depended on the basicity of anilide nitrogen. A hydrogen bonding between the anilide hydrogen and an oxygen atom of those substituents make the nitrogen less basic, resulting in the slower rearrangement.

• Animal cells and systems
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• v.1 no.4
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• pp.629-635
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• 1997

Previously we reported the migration and rearrangement of a chloroplast gene cluster into mitochondria. The exact genomic locations of the clusters, modes of the gene rearrangement and mechanisms of the interorganellar migration of the clusters have yet to be understood. The detailed analysis needs to include a larger region of DNA surrounding each cluster. To study DNA rearrangement and migration in more detail a cosmid library was constructed using the total rice genomic DNA including nuclear, chloroplast and mitochondrial DNA. From this cosmid library, a sub-library was obtained by selecting the clones hybridized to various regions of chloroplast DNA. According to the hybridization pattern 136 clones from the sub-library were classified into 29 groups. Detailed analysis of these clones revealed that in addition to authentic chloroplast DNA, the clones contain its homologs resulted from rearrangement and mutation. We analyzed two clones in detail, which contain different rp12 homologs resulted from rearrangement and/or migration, respectively.

• Archives of Pharmacal Research
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• v.16 no.2
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• pp.152-154
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• 1993

By using N-bromophthalimide (NBP) as halonium ion source for the Hofmann rearrangement, a series of primary amide could be ocnverted to the corresponding cabamate in excellent yields. So NBP was throught to be very effective and practical halonium ion source for the Hofmann rearrangement.

• Journal of the Korean Chemical Society
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• v.11 no.4
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• pp.173-178
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• 1967

The rearrangement of ${\beta}$-4-nitroazoxybenzene into 4-hydroxy-4'-nitroazobenzene in strongly acidic solutions has been as certained by UV spectrophotometry. The kinetics of the rearrangement in 20 vol. % ethanol and 80 vol. % of aqueous sulfuric acid-water solutions has been studied, and the rearrangement was found to be acid catalyzed pseudo-frst-order reaction. The mechanism of the rearrangement is also discussed.

• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1657-1660
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• 2004

Several critical geometries associated with the rearrangement of $CH_3SNO_2\;to\;CH_3SONO$ are calculated with the density functional theory (DFT) method and compared with those of the ab initio molecular orbital methods. There are two probable pathways for this rearrangement, one involving the transition state of an oxygen migration and the other through the homolytic decomposition to radicals. The reaction barrier via the transition state is about 60 kcal/mol and the decomposition energy into radicals about 35 kcal/mol, suggesting that the reaction pathway via the homolytic cleavage to radical species is energetically favorable. Since even the homolytic cleavage requires large energies, the rearrangement reaction is unlikely without the aid of catalysts.

• Bulletin of the Korean Chemical Society
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• v.22 no.4
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• pp.432-434
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• 2001

• Journal of the Korean Chemical Society
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• v.23 no.1
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• pp.42-45
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• 1979

The experimental procedures of Beckmann rearrangement mostly involve the use of vigorous conditions such as strongly acidic reagents (conc. HCl, $H_2SO_4$, $PCl_5$, etc.) or elevated temperatures, which frequently cause isomerization of ketooximes prior to rearrangement.We have effected the Beckmann rearrangement on $5{\alpha}$-cholestan-3-one oxime using the carbon tetrachloride-triphenylphosphine reagent under mild, neutral conditions to give 3-aza-A-homo-$5{\alpha}$-cholestan-4-one. This new, mild, facile and rapid general method of Beckmann rearrangement is presented, and compared with the classical (more conventional) Beckmann reagent of polyphosphoric acid.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.337-346
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• 2014

Trifluoromethylthiol functional group(이하 -SCF3)은 약학적으로 유용한 물질이다. 이 연구는 최근 개발된 Shibata의 Direct trifluoromethylthiolation reaction의 반응 메커니즘을 계산화학적으로 평가했다. 반응 메커니즘은 크게 Carbene formation, Rearrangement, Electrophilic SCF3 reagent generation 세 단계로 나눌 수 있다. 각 과정에 대해 구조에 대한 full optimization이 진행되었고, 특히 alpha-carbene sulfonyl species의 thermal rearrangement에 관한 첫번째 계산화학적 평가가 이루어졌다.