• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.3083-3087
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• 2013

Diacetylene lipid monomers possess the capability to self-assemble into vesicles via polymerization under ultraviolet irradiation, resulting in the formation of polydiacetylene (PDA) liposomes. Exposure of the polymerized vesicles to external stimuli is known to induce a unique blue-to-red color transition. The cyclic oligosaccharide ${\alpha}$-cyclodextrin known for its use in many applications, such as drug delivery, purification, and stimulus sensing, is able to form an inclusion complex with poly(ethylene glycol) (PEG) in aqueous solution. In this study, we prepared polymeric liposomes with PEG (PEG-PDA) with the aim of improving the stability of the vesicles and colorimetric response toward ${\alpha}$-cyclodextrin. We demonstrated that PEG-PDA liposome displays unique characteristics compared with native PDA liposome and it also shows apparent chromic properties of the inclusion complex formation with ${\alpha}$-cyclodextrin.

• Bulletin of the Korean Chemical Society
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• 제17권6호
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• pp.506-510
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• 1996

The syntheses and photoreactions of haloarenes, in which the aryl and haloaryl moieties are tethered by a simple alkyl group, were studied. For 2-benzyl-1-halobenzene, in which two aryl moieties were connected by methylene group, photoreduced product, diphenylmethane, was obtained along with the minor formation of the photocyclized product, fluorene, in acetonitrile solvent. For 1-halo-2-phenethylbenzene, in which two aryl moieties were connected by ethylene group, photocyclized products, 9,10-dihydrophenanthrene and phenanthrene, were obtained along with the minor formation of photoreduced product, bibenzyl, in acetonitrile solvent. The photoreaction selectivities in several solvent systems were studied: In cyclohexane, 2-benzyl-1-chlorobenzene was photoreduced more effective than 2-benzyl-1-bromobenzene; In the presence of NaOH, 1-halo-2-phenethylbenzenes gave 9,10-dihydrophenanthrene and, in the presence of toluene, they gave phenanthrene. A radical reaction mechanism is proposed for the explanation of the reactions. This study shows that the photoreaction of haloarene, in which haloaryl and aryl moieties are tethered by ethylene group, can be used for ring formation of 9,10-dihydrophenanthrene otherwise difficultly accessible.

• Korean Chemical Engineering Research
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• 제45권3호
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• pp.209-214
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• 2007

Sr hexaaluminate($Sr_{1-x}La_xMnAl_{11}O_{19-\alpha}$)와 금속 alkoxide를 전구체로, 1-butanol과 ethylene glycol을 각각 용매로 사용한 sol-gel 법으로 합성하였다. 용매 변화에 따른 Sr hexaaluminate의 물리적 특성을 TG/DTA, XRD 및 $N_2$ adsorption을 이용하여 분석하였다. 합성 후 건조한 시료에 대한 열분해 거동을 분석한 결과는 1-butanol을 용매로 사용하여 합성한 hexaaluminate와 비교할 때, ethylene glycol을 용매로 이용한 경우 용매의 분해반응과 dehydroxylation 반응이 관찰되었고, 결정생성 온도도 상승하였다. Dehydroxylation 반응과 결정생성온도의 상승은 hexaaluminate의 소결현상을 가속시켜 낮은 비표면적의 원인이 되었다. 메탄에 대한 연소 반응으로 표면적 차이가 촉매 활성에 영향을 주었음을 확인하였다.

• Journal of Plant Biotechnology
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• 제47권3호
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• pp.194-202
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• 2020

The sweetpotatoes (Ipomoea batatas) generate adventitious roots (ARs) from cut stems that develop into storage roots and make for an important means of propagation. However, few studies have investigated the hormones involved in AR development in sweetpotato. In this study, the expression patterns of hormone-related genes involved in AR formation were identified using the transcriptome data. RNA-seq data from stems grown for 0 and 3 days after cutting were analyzed. In addition, hormone-related genes were identified among differentially expressed genes (DEGs) and filtered genes, and cluster analysis was used to characterize expression patterns by function. Most hormone-related regulated genes expressed 3 days after growing the cut stems were abscisic acid (ABA)-related genes, followed by ethylene- and auxin-related genes. For ABA, the biosynthesis genes (including genes annotated to NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (NCED3)) and signal transduction and perception genes (including genes annotated to PROTEIN PHOSPHATASE 2Cs (PP2Cs)) tended to decrease. Expression patterns of auxin- and ethylene-related genes differed by function. These results suggest that ABA, auxin, and ethylene genes are involved in AR formation and that they may be regulated in a hormone function-dependent manner. These results contribute to the identification of hormone functions during AR formation and may contribute to understanding the mechanism of AR formation in the sweetpotato.

• 한국작물학회지
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• 제49권5호
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• pp.363-367
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• 2004

The deep irrigation of rice plants brings about some beneficial effects such as reduced tiller production which results in the formation of bigger panicles, prevention of chilling injury, reduced weed growth, etc. The present study was carried out to examine the involvement of ethylene in the suppression of tiller production due to deep water irrigation in rice (cv. Dongjinbyeo). The ethylene production was induced in leaf sheath within 24 hours after the deep water irrigation and has increased even until 30 days after the treatment, recording 4.5-fold increase as compared to the shallow-irrigated rice plants. In the deep water irrigated rice plants, ethylene was accumulated to a high concentration in the air space of submerged leaf sheath as the irrigated water deterred the diffusion of ethylene out of the leaf sheath and ethylene biosynthesis was accelerated by the deep irrigation as well. The ethylene concentration recorded 35-fold increase in the deep-irrigated rice plants for 35 days. The tiller production was reduced significantly by the deep irrigation with water, the tiller bud, especially tertiary tiller bud differentiation being suppressed by the deepwater irrigation treatment, whereas the rice plants deep-irrigated with solutions containing $10^{-5}$ M or $10^{-6}$ M silver thiosulfate (STS), an action inhibitor of ethylene, showed the same or even higher production of tillers than those irrigated shallowly with water. This implies that the ethylene is closely linked with the suppression of tiller production due to deep water irrigation. In conclusion, ethylene, which was induced by hypoxic stress and accumulated in the leaf sheath due to submergence, played a key role in suppressing the tiller production of the deepwater irrigated rice.

• 한국잡초학회지
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• 제9권2호
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• pp.90-96
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• 1989

생장조절물질(生長調節物質)의 처리(處理)가 콩나물의 ethylene 발생(發生)에 미치는 효과(效果)에 관(關)하여 연구(硏究)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 콩나물의 ethylene 발생(發生)에 미치는 auxin의 처리(處理)는 뚜렷한 영향(影響)이 보이지 않았다. 2. 콩나물의 ethylene 발생(發生)에 미치는 cytokinin 및 유사물질(類似物質)의 처리효과(處理效果)는 BA가 ethylene 발생(發生)을 크게 촉진(促進)시킨 반면(反面) kinetin, zeatin, zeatin riboside는 미미(微微)하였다. 3. 콩나물의 ethylene 발생(發生)에 미치는 BA 농도별(濃度別) 처리효과(處理效果)는 농도(濃度)가 높을 수록 ethylene 발생(發生)이 증가(增加)되었다. 4. BA의 처리(處理)는 단기간내(短期間內) ethylene 발생(發生)을 증가(增加)시켜서 신장억제(伸長抑制)와 비대촉진(肥大促進) 효과(效果)를 보이나 4PU-30은 ethylene 발생(發生)을 지속적(持續的)으로 증대(增大)시키는 효과(效果)를 보였다. 5. 생장조절물질(生長調節物質)이 처리(處理)된 콩나물에서의 ethylene 발생정도(發生程度)는 BA 25ppm > IAA 25 + BA 25 ppm ${\geq}$ 4 PU-30 25 ppm > IAA 25 ppm > control 순(順)이었다. 6. 콩나물의 세근발생(細根發生)은 cytokinin 중(中) BA에 의(依)해 억제(抑制)되며, 비대촉진(肥大促進)은 ethylene에 의해 촉진(促進)되는데, BA는 ethylene 발생(發生)을 크게 촉진(促進)시켰다.

• 한국미생물·생명공학회지
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• 제26권3호
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• pp.195-199
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• 1998

Ethylene을 생성하는 호알칼리성 Bacillus sp. AIk-7를 분리 동정하였고, Bacillus sp. AIk-7의 ethylene 생성 경로와 전구 물질을 규명하기 위한 일환으로 이 균주의 intact cell과 cell-free system에서의 다양한 기질의 전환효과를 검토하였다. Intact cell과 cell-free system 모두에서 ethylene 생성을 극대화하기 위한 전환 조건은 3$0^{\circ}C$, pH 10.3으로 조사되었고, 기질 전환 효과를 검토한 결과 methionine(Met)과 1-amlnocyclopropane-1-carboxylic acid(ACC)가 압도적으로 많은 ethylene을 생성하였다. Cell-free system에서 저해제의 영향을 살펴본 결과 EDTA억제 효과로 2가 양이온이 필요함을, AOA 억제효과로 transaminase가 필요함을 알 수 있었다. Azide는 Met에서 ACC로의 단계에선 억제효과가 있었으나, ACC ethylene 전환 단계에선 오히려 활성효과를 보여주었다. 식물에서는 ACC에서 ethylene 과정은 Co$^{2+}$에 의해 저해받는데 반해 Bacillus sp. AIk-7은 Co$^{2+}$에 의해 ACC에서 ethylene과정이 10-70배 활성을 보였다. 이상의 결과를 통해 Bacillus sp. AIk-7에 의한 ethylene 생성 전구체는 Met과 ACC일 가능성이 있다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1995년도 춘계학술발표회 프로그램 및 초록
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• pp.19-20
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• 1995

• 대한화학회지
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• 제28권2호
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• pp.109-113
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• 1984

여러가지 함량으로 은을 입힌$ Ag/{\alpha}-Al_2O_3$와 $Ag/SnO_2$상에서의 반응실험과 촉매의 Auger spectra, $SnO_2$에 흡착된 산소의 EPR spectra를 비교하여 담체의 종류가 에틸렌 산화반응의 활성과 선택성에 미치는 영향을 조사하였다. $SnO_2$상에서는 흡착산소중 O-가 반응에 참여하여 ethylene를 완전 산화하는 방향으로 유도하므로써 ethylene oxide 생성의 선택성을 저하시키는 것 같다.

• Bulletin of the Korean Chemical Society
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• 제28권10호
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• pp.1763-1770
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• 2007

Strong solid acid catalysts, NiO/Al2O3-TiO2/WO3 for ethylene dimerization were prepared by the addition of Al2O3 and the modification with WO3. The acid sites and acid strength were increased by the inductive effect of WO3 species bonded to the surface of catalysts. The larger the dispersed WO3 amount, the higher both the acidity and catalytic activity for ethylene dimerization. The addition of Al2O3 to TiO2 up to 5 mol% enhanced acidity and catalytic activity gradually due to the interaction between Al2O3 and TiO2 and consequent formation of Al-O-Ti bond.