• Journal of Plant Biology
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• v.33 no.4
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• pp.309-314
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• 1990

Effect of mannose on auxin-induced ethylene production in corn (Zea mays L.) coleoptiles was studied. Auxin induced ethylene production decreased in proportion to mannose concentrations. The inhibitory effect of mannose appeared after 2 h of incubation. Ethylene production was significantly depressed by mannose at high concentration (10-5M-10-4M) of indole acetic acid (IAA), but not at low concentrations (10-8M-10-6M). The inhibition of auxin-induced ethylene production by mannose was specific, since other sugars such as galactose, glucose, sucrose and mannitol did not have an inhibitory effect. In an effort to elucidate mechanisms of mannose the effect on the auxin induced ethylene production, effect of the sugar on ACC synthase activity and ACC induced ethylene production was studied. Mannose failed to inhibit ACC mediated ethylene production, but decreased both the ACC content and ACC synthase activity in the tissue. These results suggest that the inhibitory effect of mannose on auxin induced ethylene production results from suppression of auxin induction of ACC synthase.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.383-390
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• 1993

This experiment was carried out in the green house at Tokyo University of Agriculture in 1992 to investigate the relationship between lodging resistances and specific morphological characters and to examine the effects of nitrogen top-dressing and growth retardant on changes of the endogenous ethylene content in rice plant. Inabenfide did not affect significantly yield, yield component, chlorophyll content, and $CO_2 assimilation but, decreasing plant height when growth regulators were applied at booting stage, decreasing internode elongation, and increasing culm thickness and diameter of the third and fourth internode. While, nitrogen top-dressing usually showed to effect increasing vegetative growth such as plant height, tiller number, and morphological characteristics but, were not significantly affected the chlorophyll content and $CO_2 assimilation. Ethylene evolution was dramatically changed with nitrogen top-dressing and growth retardant. Application of Inabenfide at 15 days before heading inhibited ethylene evolution in the all nitrogen levels. Higher nitrogen top-dressing showed higher ethylene evolution than that of low nitrogen level. High positive correlation was detected between nitrogen application and ethylene evolution.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.215-223
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• 1987

This experiment was carried out to determine the effect of nitrogen application on the cold tolerance of rice plant, with treatment of three levels of nitrogen and three times of application under the low temperature at tillering and panicle initiation stages. The higher cold tolerance variety was increased in plant height and number of tillers on high nitrogen level during the low temperature treatment. Nitrogen content of leaf blade was increased, but carbohydrate content was decreased during the low temperature treatment at tillering stage. Ethylene evolution from leaf was remark-ably increased just after low temperature treatment. Highly significant negative correlation was observed bet-ween the nitrogen content of leaf blade and percentage of filled grain under low temperature condition at reproductive growth stage.

• Elastomers and Composites
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• v.54 no.1
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• pp.61-69
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• 2019

Poly(ethylene-co-vinyl acetate) (EVA) is a copolymer of ethylene and vinyl acetate (VA). It is important to determine the VA content of EVA, since the properties of EVA depend highly on the VA content. EVA copolymers have been used in a wide range of applications appropriate for the different VA contents. IR, NMR, and TGA are generally used for determination of the VA content of EVA copolymers. Of these, TGA is the most reliable method and can be applied to cured EVAs. Analytical methods for determination of the VA content and properties of EVA copolymers via TGA were herein reviewed. Thermal behaviors of EVA copolymers (glass transition temperature ($T_g$), melting point ($T_m$), and crystallization temperature ($T_c$)) determined by DSC were also reviewed. Analysis of the related literature revealed that the $T_g$, $T_m$, and $T_c$ decrease by about 0.46, 1.36, and $2.08^{\circ}C$, respectively, for every 1 wt% in VA content. A method for determining the degree of crosslinking of cured EVA copolymers was also reviewed, and the degree of crosslinking tends to increase with the decrease in the VA content.

• Food Science and Preservation
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• v.4 no.1
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• pp.39-44
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• 1997

Ethylene was treated or inhibited to investigate its effect on the physiological changes related to induction of flesh browning in Fuyu persimmon fruit. The response of fruit to ethylene was so slight, that the Fuyu fruit seemed to possess a similar characteristic to non-climacteric fruit. The flesh browning was however enhanced by ethylene treatment, although any significant increment of phenolic content or PPO activity in flesh tissue was not detected. Ethylene induced not only increasing of ion leakage from fruit tissue, but the fatty acids extracted from ethylene-treated fruit tissue were also more saturated. It was suggested that ethylene be related in the changing of membrane permeablity via saturating of fatty acid in membrane lipid. That could result in increased leakage of vacuole-stored phenolic compounds, which oxidized further by PPO to cause fruit flesh to brown.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.46-49
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• 1984

Ethylene evolution of leaves was measured in the samples of barley and wheat grown in the various conditions and treatments. The older and stepped leaf of barley had tended to the tendency to contain more ethylene than the younger and sound leaf. Relatively high concentration of ethylene was evolved in the samples which the detecting time was delayed and so was in the samples incubated at high temperature. The higher evolution of ethylene was determined by the barley plant grown in the field and with compost application compared to the samples grown in the pot and with composite fertilizer application, however the flooding treatment resulted in decreasing ethylene evolution comparing to untreated barley and wheat. The prostrate type and higher chrolophyll content leaves of wheat appeared to produce more ethylene than erect and lower chrolophyll leaves did.

• Textile Coloration and Finishing
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• v.3 no.3
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• pp.23-28
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• 1991

Poly(1, 4-cyclohexanedimethylene/ethylene terephthalate), PCET was prepared by condensing 1, 4-cyclohexanedimethanol(CHDM) and ethylene glycol with dimethylterephthalate(DMT), and some thermal properties of PCET were studied by DSC at a heating rate $20^{\circ}C$min. On increasing the CHDM content in PCET up to 20 mole%/DMT, the glass transition temperature(Tg) decreased a little and the crystallizability reduced sharply, and from 20 to 50 mole %/DMT the $T_g$ did not changed and the crystallization temperature was not detected. But on increasing the CHDM content above 70 mole %/DMT the TEX>$T_g$/ and the melting temperature increased.

• Horticultural Science & Technology
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• v.34 no.5
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• pp.746-754
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• 2016

This study was conducted to assess the effect of ethylene producing tablet (patent no.10-1574011) and treatment period on quality and storability of banana (AAA - Cavendish group) fruit imported into Korea from the Philippines. Three and five days of treatment periods, and different concentrations of ethylene tablet (50 ppmv, 100 ppmv) and control (standard ethylene gas treatment at a concentration of 100 ppmv) were used for the study. Slightly higher respiration rate was observed in banana fruits treated with 50 ppmv in both 3 and 5 days after treatments as compared to the control. Better storability was observed with banana fruits treated with 50 ppmv and 100 ppmv as compared to the control. All the treatments were shown a decrease in firmness as the storage days proceeded. The highest firmness was recorded from 50 ppmv on the initial day of storage while the lowest was recorded from 100 ppmv on 9 day storage. It was observed that banana fruits could be stored for up to 12 days without losing their color quality in all treatments except for the control. However, the quality of fruits at the control rapidly decreased (lost marketability) after 9 days of storage. Banana fruits treated with ethylene tablet with 100 ppmv for 5 days recorded the highest soluble solids content (SSC) at the beginning of storage period which was similar with the control. However, banana fruits treated with ethylene tablet with 100 ppmv for 3 days showed better storability than the control. On the other hand, ethylene tablet with 50 ppmv for 5 days of treatment has extended banana shelf life without affecting peel color, firmness and SSC content. Hence, these results indicate that banana fruits treated with ethylene tablet with 100 ppmv for 3 days or /and 50 ppmv for 5 days are an optimum for ripening of banana to be used for market and ultimate consumption.

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.683-687
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• 2002

We have investigated the effect of the number of ethylene oxide (EO) units inside poly(ethylene glycol)dimethacrylate (PEGDMA) on the ionic conductivity of its gelled polymer electrolyte, whose content ranges from 50 to 80 wt%. PEGDMA gelled polym er electrolytes, a crosslinked structure, were prepared using simple photo-induced radical polymerization by ultraviolet light. The effect of the number of EO on the ionic conductivity was clearly shown in samples of lower liquid electrolyte content. We have concluded that the ionic conductivity increased in proportion to both the number of EO units and the plasticizer content. We have also studied the electrochemical properties of 13PEGDMA (number of EO units is 13) gelled polymer electrolyte.

• Archives of Pharmacal Research
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• v.18 no.1
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• pp.8-11
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• 1995

Biodegradability of poly $Poly({\gamma}-benzyl L-Glutamate)/poly(ethylene oxide)/Poly({\gamma}-benzyl L-Glutamate)$ block copolymer (GEG) having different content of poly(ethylene oxide) (PEO) were examined using magnetite as a tracer in mice. GEG microspheres containing magnetite were injected into mice through tail vein. Biodegradability and tissue distribution of microspheres were examined by analyzing the amount of magnetite in the microspheres recollected from mice organs after specific time interval. The results showed that GEG microsphere of high content of PEO was degraded more rapidly than those of low content of PEO in the mice organs.