• Journal of Plant Biology
• /
• 제33권4호
• /
• pp.309-314
• /
• 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.

• 한국작물학회지
• /
• 제38권5호
• /
• pp.383-390
• /
• 1993

본 실험은 1992년 일본 동경농업대학 온실에서 질소 추비와 생장억제제 처리가 벼의 생육과 도복형질에 미치는 형태학적 특성과의 관계를 조사함과 동시에 내성 에틸렌 발생에 미치는 영향을 구명하기 위하여 실험을 수행한바 아래와 같은 결과를 얻었다. 1. 식물생장억제제인 Inabenfide는 초장은 감소시켰지만 수량구성요소, 엽록소 함량, $CO_2 동화량 및 분벽에는 변화가 없었다. 2. Inabenfide를 수잉기에 처리하였을 때 절간 신장을 감소시켰으나, 세 번째와 네 번째의 절간 직경과 줄기의 두께를 증가시켰다. 3. 질소추비는 대체로 초장과 $CO_2 동화률에는 뚜렷하게 영향을 나타내지 않았다. 4. 에틸렌 발생은 생장억제제에 대하여 많은 변화를 보여 주었으며 Inabenfide를 출수 15일 전에 처리하였을 때 에틸렌 발생은 무처리구보다 낮게 나타났다. 5. 질소 추비량에 따른 에틸렌 발생은 추비량이 많을 때 발생량이 높았으며 질소 추비와 에틸렌발생 사이에는 높은 상관관계가 있는 것으로 나타났다.

• 한국작물학회지
• /
• 제32권2호
• /
• pp.215-223
• /
• 1987

본 연구는 벼의 주요생육단별로 저온하에서 질소시비량과 시비시기를 달리해서 수도품종의 내냉성과 도체내 질소함량 및 ethylene 생성량과의 관계를 명백히 함으로서, 내냉성 품종육성과 냉해경감을 위한 재배기술확립의 기초자료를 얻고자 실시한바, 그 결과는 다음과 같다. 1. 분얼기의 저온처리는 초장과 분얼을 크게 억제시켰으며, 질소시비량의 증가는 저온하에서도 초장, 분얼수는 다소 증가되나, 저온에 약한 태백벼가 현저히 적었다. 그러나 저온처리 종료후 회복력은 내냉성이 약한 태백 벼가 현저했다. 2. 분얼기, 감수분열기, 등숙기 저온처리는 엽신의 질소함양은 증가시키나 탄수화물함양은 감소하는 영향이었다. 3. 감수분열기는 질소시비량의 증가에 따라 저온에 의한 임실비율이 감소하며, 그 경향은 내냉성이 약한 품종에서 현저했으며, 엽신의 질소함양과 임실비율간에는 부의 유의 상관관계가 인정되었다. 4. 출수기의 실비의 증비는 저온하에서 등숙률을 저하시켰으며, 그 경향 내냉성이 약한 품종에서 뚜렷했다. 5. 엽신의 ethylene 생성량은 품종간 큰 차이를 나타냈고, 질소시비량 증가에 따라 ethylene 생성량이 감소하는데. 이 같은 결과는 품종의 내비성 또는 내냉성과 관계가 있는 것으로 사료된다. 6. 엽신의 ethylene 생성량의 저온처리기간 또는 처리후의 추이를 보면, 저온처리와 함께 급격히 감소하고, 저온처리 종료후는 다시 증가하나, 그 경향은 시비하에서는 현저한 증가를 보이나 질소증비에 따라 생성량은 현저히 감소하였다. 또한 품종간 차이가 큼을 인정할 수 있었다.

• Elastomers and Composites
• /
• 제54권1호
• /
• pp.61-69
• /
• 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.

• 한국식품저장유통학회지
• /
• 제4권1호
• /
• pp.39-44
• /
• 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.

• 한국작물학회지
• /
• 제29권1호
• /
• pp.46-49
• /
• 1984

맥류의 생육과 Ethylene 대사와의 관계를 측정한 몇가지 결과를 소개하면 다음과 같다. 1. 보리 엽의 Ethylene 생성량은 하위엽이 상위엽보다 많고 답압을 한 것이 하지 않은 것보다 많았다. 2. 엽신절단후 시간이 경과함에 따라 Ethylene 생성량은 증가하였는데 pot에서 보다 포장에서 재배한 것이 많았고 절엽후 Incubation의 온도가 높을수록 많았으며 주간이 야간보다 많은 경향이었다. 3. 밀의 Ethylene 생성량은 초형이 직립형인 품종 보다 포복형인 품종일수록 많고 엽록색 함량이 적은 품종보다 많은 품종일수록 증가하였다. 4. 맥류엽의 Ethylene 생성량은 복합비료보다 퇴비를 시용한 것이 많았고 담수를 한 것은 하지 않은 것보다 저하하는 경향을 보였다.

• 한국염색가공학회지
• /
• 제3권3호
• /
• pp.23-28
• /
• 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.

• 원예과학기술지
• /
• 제34권5호
• /
• pp.746-754
• /
• 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
• /
• 제23권5호
• /
• pp.683-687
• /
• 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
• /
• 제18권1호
• /
• pp.8-11
• /
• 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.