• Journal of the Korean Chemical Society
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• v.28 no.2
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• pp.109-113
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• 1984

The effects of various supports on the activity and the selectivity for the ethylene oxidation was investigated over$ Ag/{\alpha}-Al_2O_3$ and $Ag/SnO_2$ by Auger, EPR spectroscopy and reaction studies. The results indicate that over $Ag/SnO_2$ catalyst O- chemisorbed on $SnO_2 $participates in the complete oxidation of ethylene lowering the selectivity for the formation of ethylene oxide.

• Fire Science and Engineering
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• v.23 no.5
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• pp.50-56
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• 2009

Explosion limit and autoignition temperature are the major properties used to determine the fire and explosion hazards of the flammable substances. Explosion limit and autoignition temperature for safe handling of ethylene were investigated. By using the literatures data, the lower and upper explosion limits of ethylene recommended 2.6vol% and 36vol%, respectively. Also autoignition temperatures of ethylene with ignition sources recommended $420^{\circ}C$ at the electrically heated crucible furnace (the whole surface heating) and recommended about $800^{\circ}C$ in the local hot surface. The new equations for predicting the temperature dependence and the pressure dependence of the lower explosion limits for ethylene are proposed. The values calculated by the proposed equations were a good agreement with the literature data.

• Journal of Adhesion and Interface
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• v.4 no.3
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• pp.14-20
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• 2003

In order to study the radiation curing behavior of poly(ethylene glycol 400) dimethacrylate and ethylene glycol dimethacrylate, we investigated the influence of temperature and photoinitiator concentration by photo-DSC. As the number of ethylene glycol unit, the concentration of photoinitiator, and the reaction temperature increased, the reaction speed of PEG400DMA and EGDMA increased. Although the reaction speed of PEG400DMA was lower than EGDMA, the overall conversion of PEG400DMA was high.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.5
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• pp.415-420
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• 2018

The development of sail gas has increased the production of ethane as well as natural gas. The decline in the market price for ethane has led to a change in the petroleum-based ethylene production process into an ethane-based ethylene production process and an increase in the ethane/ethylene trade volume. Large-scale ethane/ethylene carrier have been needed due to an increase in long-distance trade from the US, and cargo type change have leaded to consider a liquefaction process to re-liquefy Boil-Off gas generated during the voyage. In this paper, the liquefaction system of Liquefied Ethane Gas carrier was evaluated with Low-GWP (Low-Global Warming Potential) refrigerant and process parameters, Boil-Off Gas pressure and expansion valve outlet pressure, were optimized. Low-GWP refrigerants were propane (R290), propylene(R1270), carbon dioxide(R744) was considered at two type of liquefaction process such as Linde and cascade cycle. The results show that the optimal pressure point depends on the individual refrigerant and the highest liquefaction efficiency of carbon dioxide (R744) - propane (R290) refrigerant.

• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.276-284
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• 1988

The crystallization behaviours of poly(ethylene terephthalate) modified by 1, 3-propane diol, 1, 5-pentane diol, 1, 6-hexane diol, or poly(ethylene glycol) of molecular weight 300 as a third component were studied by isothermal and nonisothermal crystallization. When the content of the third diol was about 4 mol %, the isothermal crystallization rate at the same supercooling below the melting temperature and the nonisothermal crystallization rate at the same overheating above the glass transition temperature were increased more by the shorter flexible diol unit. On the contrary the nonisothermal crystallization rate at the same supercooling below the melting temperature was increased more by the longer flexible diol unit.

• Journal of Adhesion and Interface
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• v.7 no.2
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• pp.12-18
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• 2006

Recently, as industries and technologies are increased, superior adhesives having more and more developed functions and properties have been demanded. In this article, to use the merits and viscoelastic properties of poly(ethylene/butylene) rubber resin and to supplement the demerits, semi-structure pressure sensitive adhesives (PSAs) are developed. Aslo, it can be said environmentally friendly PSAs because of not use the organic solvent and not emit volatile organic compounds (VOCs).

• Korean Journal of Plant Resources
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• v.31 no.6
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• pp.597-603
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• 2018

Inhibitory effect of colchicine on growth and gravitropic responses in Arabidopsis root was explored to find whether there was an involvement of ethylene production. It has been known that cytoskeleton components are implicated in sedimentation of statoliths to respond to gravitropism and growth. The root growth was inhibited by 25% and 40% over control for 8 hr treatment of colchicine at a concentration of $10^{-5}M$ and $10^{-7}M$, respectively. The roots treated with colchicine at the concentration of $10^{-7}M$ showed the same pattern as control in 3 hr, however, gravitropic response was decreased in the next 5 hr. The colchicine treatment at the concentration of $10^{-5}M$ inhibited the gravitropic response resulting in $60^{\circ}$ of curvature. In order to better understand the role of colchicine, the production of ethylene was measured with and without the treatment of colchicine. Colchicine increased the ethylene production by 20% when compared to control via the activation of ACC oxidase and ACC synthase activity. These results suggest that the inhibition of the growth and gravitropic responses of Arabidopsis roots by the treatment of colchicine could be attributed to the rearrangement of microtubule, and increase of ethylene production.

• Genes and Genomics
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• v.40 no.11
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• pp.1237-1248
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• 2018

Introduction Cellulose microfibril is a major cell wall polymer that plays an important role in the growth and development of plants. The gene cellulose synthase A (CesA), encoding cellulose synthases, is involved in the synthesis of cellulose microfibrils. However, the regulatory mechanism of CesA gene expression is not well understood, especially during the early developmental stages. Objective To identify factor(s) that regulate the expression of CesA genes and ultimately control seedling growth and development. Methods The presence of cis-elements in the promoter region of the eight CesA genes identified in flax (Linum usitatissimum L. 'Nike') seedlings was verified, and three kinds of ethylene-responsive cis-elements were identified in the promoters. Therefore, the effect of ethylene on the expression of four selected CesA genes classified into Clades 1 and 6 after treatment with $10^{-4}$ and $10^{-3}M$ 1-aminocyclopropane-1-carboxylic acid (ACC) was examined in the hypocotyl of 4-6-day-old flax seedlings. Results ACC-induced ethylene either up- or down-regulated the expression of the CesA genes depending on the clade to which these genes belonged, age of seedlings, part of the hypocotyl, and concentration of ACC. Conclusion Ethylene might be one of the factors regulating the expression of CesA genes in flax seedlings.

• Horticulture, Environment, and Biotechnology : HEB
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• v.59 no.6
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• pp.787-804
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• 2018

Flavor quality is import for determining consumer perception and acceptance of tomato products. In this study, 'Fendou' tomato fruit were harvested at six ripening stages and sampled to investigate the development of flavor-relevant compounds during vine ripening. Results showed that upon the initiation of ripening there was an increase in respiration rate and concomitant ethylene evolution that was associated with increased membrane permeability. In accordance with these physiological changes, flavor-relevant compounds demonstrated different expression patterns as fruit ripened, which contributed to 'red-ripe' flavor characteristics of red-ripe fruit. Based on correlation analysis between ethylene evolution and the flavor-relevant compounds during 'Fendou' tomato ripening and the other researchers' reports, the activation of System 2-dependent autocatalytic ethylene production plays an important role in the development of most flavor-relevant compounds during tomato vine ripening. Overall, our results suggested that most flavor-relevant compounds that accumulated the most during tomato fruit ripening at red stage could be under ethylene regulation and were among the most important contributors to the 'red-ripe' flavor. Due to the development of these compounds, the flavor quality at late ripening stages is different from that of fruit at early ripening stages.

• Journal of Conservation Science
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• v.25 no.4
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• pp.465-471
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• 2009

In this study, the substitution fumigation gases (15% Ethylene Oxide + 85% HFC 134a, 20% Ethylene Oxide + 80% $CO_2$, 99% Sulfuryl Fluoride + 1% Inert Gas) were applied on the metal, pigment, fabric and paper specimen. The result of the fumigation treatment with 15% Ethylene Oxide + 85% HFC 134a (200g/$m^3$, 48hours) is the color changes (${\Delta}E$) of 1st and 2nd Cu specimens showed significant difference as 3.40, 4.17. On the other hand, other specimens except for Cu showed less than 3.0 in chrominance values. The result with 20% Ethylene Oxide + 80% $CO_2$ (150g/$m^3$, 48hours) is that the color changes (${\Delta}E$) of 1st and 2nd specimens were overall less than 3.0 so that color differences were subtle and hardly recognized with naked eyes. So it is proved that the fumigation treatment with Ethylene Oxide 20% + $CO_2$ 80% is relatively stable on materials in this study. In the case of 99% Sulfuryl Fluoride + 1% Inert Gas (50g/$m^3$, 48hours), the color difference of Lead red ($PbO_4$) of pigment was more than 3.0 that was compared with contrast specimens. But chrominance values in the other specimens were less than 3.0 on average.