• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.48-51
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• 1993

Using the new type auxiliary(K-1), dyeing experiment was done at the various dyeing conditions and the effects of auxiliary on the dyeing properties of metal complex dye for the silk fiber were dicussed. The exhaust rate was higher in the auxiliary 3% o.w.f. addition than sodium sulfate 50% o.w.f. The decreasing ratio of exhaust rate according to dye concentration increasing was lower at auxiliary addition than auxiliary non-addition. The exhaust rate according to increasing dyeing temperature was higher in the auxiliary addition than non-addition.

• Journal of Practical Agriculture & Fisheries Research
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• v.3 no.1
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• pp.79-84
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• 2001

The experiment were carried out to establish the optimal condition of bulblet size, low temperature treatment and time of incubation in acclimatization on stem emergence of Lilium oriental hybrids. The large size bulblet was better than middle and small size bulblets in percentage of stem emergence and weight of bulblets. The highest percentage of stem emergence was 95% in large size bulblet 'Acapulco' but small size bulblet of 'Casablanca' was no stem emergence. Low temperature treatment(5℃)for breaking dormancy was needed at least more than 9weeks. Weight of bulblets and percentage of stem emergence was not good in 5℃ treatment for 6 weeks. The best stem emergence showed 5 month growing in vitro and the weigh test bulblets during acclimatization of bulblet

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.77-77
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• 2010

그래핀(Graphene)은 한 겹(layer)의 2차원 판상 구조에 탄소원자들이 육각형의 기본 형태로 배열되어 있는 나노재료로서, 우수한 역학적 강도와 화학적, 열적 안정성 및 흥미로운 전기 전자적 성질을 가지고 있는 것으로 알려져 있다. 최근, 이러한 특징적이고도 우수한 물성으로 인하여 기초물성 연구에서부터 차세대 응용까지 고려한 각종 연구들이 활발하게 진행되고 있다. 일반적으로 그래핀을 얻는 방법에는 물리 화학적 박리, 열화학증기증착법(TCVD), 탄화규소의 흑연화, 흑연산화물의 환원 등의 방법들이 알려져 있다. 그 중 TCVD법이 두께의 균일성이 높은 그래핀을 합성하는데 가장 적절한 것으로 알려져 있다. 그러나 TCVD법은 탄소를 포함하는 원료가스를 분해하기 위하여 고온의 공정을 필요로 하게 되지만, 향후 산업적 응용을 고려한다면 대면적 그래핀의 저온합성법 개발은 풀어야 할 시급한 과제로 인식되고 있다. 현재는 메탄을 원료가스로 사용하여 $900^{\circ}C$ 이상에서 그래핀을 합성하는 추세이고, 최근 아세틸렌등의 활성원료가스를 이용하여 $900^{\circ}C$ 이하에서 저온 합성한 연구결과들도 속속 보고되고 있다. 본 연구에서는 고주파 플라즈마를 이용하여 비교적 저온에서 탄소원료가스를 효율적으로 분해하고, 확산플라즈마 영역에 TCVD 챔버를 결합한 하이브리드 화학증기증착법을 이용하여 그래핀의 저온합성을 도모하였다. 원료가스로는 메탄을 사용하였고, 기판으로는 전자빔증착법으로 증착한 니켈 박막 및 구리포일을 사용하였다. 실험결과, 그래핀은 $600^{\circ}C$ 부근의 저온에서도 수 층으로 이루어진 그래핀이 합성된 것을 확인하였다. 합성한 그래핀은 분석의 용이함 및 향후 다양한 응용을 위하여 실리콘산화막 및 투명고분자 기판 위에 전사(transfer)하였다. 합성된 그래핀의 구조평가를 위해서는 광학현미경과 Raman분광기를 주로 사용하였으며, 원자힘현미경(AFM), 주사전자현미경(SEM), 투과전자현미경(TEM) 등도 이용하였다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.2
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• pp.152-156
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• 1984

Germination and emergence of 16 barley cultivars bred in Korea were studied under different low temperature conditions in laboratory at Suweon. This study revealed that the barley cultivars differed markedly in their germination rate index (GRI), emergence rate index (ERI), and dry matter weight. The seeds of Baekdong, Namhaebori, Gangbori and Buheung germinated better than others in $4^{\circ}C$ plot. Yeongsanbori, Kwangseong and Baekdong had very poor ERI values, but Buhobori, Namhaebori, Oweolbori, Albori and malting barley, Sacheon 6 had very good ERI values. Germination rate index were not correlated with emergence rate index under any temperature conditions. The correlation coefficient between ERI of $4^{\circ}C$ and $7^{\circ}C$ plots was very high. Those results showed that for screening the varieties or lines with good emergence capacity under low temperature conditions ERI, FS and dry matter weight would be available.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.6
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• pp.481-486
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• 1990

A survey was carried out on the cold-induced sterility of paddy rice in 1988 in the alpine area of Kangweon province when cold spell occurred during late July to early August, During this period minimum temperature as low as 8.5$^{\circ}C$ and 5.7$^{\circ}C$ was recorded at Dunnae and Jinbu, respectively. The rice cultivars, which encountered this cold spe]J at meiotic stage of microspore, were damaged by sterility in most alpine areas of higher than 300m in altitude. To secure spilkelet fertility higher than 80% it was estimated that the minimum and average air temperature accumulated during 13 days of meiotic stage should be higher than 2$25^{\circ}C$ and 285$^{\circ}C$, respectively and/or the duration of lower than 17$^{\circ}C$ in minimum temperature should not exceed fivedays during that period.

• Korean Chemical Engineering Research
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• v.49 no.4
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• pp.417-422
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• 2011

The low temperature pyrolysis of ABS resin has been carried out in a batch reactor under the atmospheric pressure. The effect of the reaction temperature on the yield of pyrolytic oils has been determined in the present study. The oil products formed during pyrolysis were classified into gas, gasoline, kerosene, gas oil and heavy oil according to the petroleum product quality standard of Ministry of Knowledge Economy. The conversion reaches 80% after 60 min at $500^{\circ}C$ in the pyrolysis of ABS resin. The amount of the final product was ranked as gas heavy oil > gasoline > gas oil > kerosen based on the yield. The yields of heavy oil and gas oil increase with an increase in the reaction time and temperature.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.377-384
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• 2006

This study was conducted to investigate the effects of chemical application and amout of soil moisture on low temperature stress of cucumber seedling under the greenhouse conditions. When chilling treatments ($2^{\circ}C$) were begun at 07:00AM, survival rates of seedlings of two conditions; -0.3 bar and -5.5 bar were 28.3% and 83.3% respectively. But when chilling treatments were begun at 6:00PM - even the soil moisture condition was -0.3 bar - the survival rate was above the 87%. When reducing the soil moisture from -0.3 bar to -9.0 bar, ABA content in leaf was inc.eased by 6.5fo1d. Spraying of abscisc acid (ABA) before or after the chilling significantly increased the survival rates of seedlings, decreased the amounts of leaking electrolytes and prevented the yield reductions. ABA application on the soil before the chilling appeared to be more effective than the application after the chilling with foliar spray. Spraying of ABA ($10^{-5}M$), urea (0.2%) or $KH_2PO_4$ was effective in counteracting the low temperature, which causes growth deterioration and yield reduction in cucumbers.

• Food Science and Preservation
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• v.18 no.5
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• pp.651-660
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• 2011

This study was conducted to evaluate the quality characteristics of and chilling injury development in 'Ooishiwase' plum fruits after harvest, according to the ripening stage and storage temperature. The fruits were harvested at three ripening stages (60, 80, and >90% skin color) and were then stored at 1, 4, 5, 6, and $20^{\circ}C$ cold-storage rooms for up to 48 days. The fruit quality parameters, respiration patterns, and chilling injury development were monitored during the storage periods and the three days of subsequent ripening at $20^{\circ}C$. The fruits harvested at the 60%-skin-color stage maintained the flesh firmness, color, weight loss, and TA, and their respiration rates and ethylene production were decreased compared with the 80%-or >90%-skin-color fruits, at a lower storage temperature. The major symptoms of chilling injuries in the Ooishiwase plums were gel breakdown, flesh browning, and flesh translucency. These symptoms appeared at all the low-storage-temperature and ripening treatment stages. When the fruits, however, were harvested at a more immature stage and were stored at a lower storage temperature, the chilling injury development decreased. These results show that the development of chilling injury in Ooishiwase plums is related to the climacteric behavior during cold storage.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.11a
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• pp.46-47
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• 2001

황을 포함하는 촉매는 황을 포함하지 않은 촉매보다 저온영역에서 상대적으로 우수한 활성을 갖는 것으로 관찰하였다. $V_2$$O_{5}$가 담지된 촉매는 황에 인해 표면에 polymeric vanadate가 형성되었기 때문인 것으로 확인되어 polymeric vanadate가 탈질제거 활성에 유리한 활성점으로 확인되었다. 또한 활성저하 실험에서 반응온도의 영향이 큰 것으로 확인되었는데 $300^{\circ}C$이상의 반응온도에서는 생성된 염이 제거되는 온도영역이므로 염의 생성으로 인한 활성 저하는 확인 할 수 없다. 그러므로 $300^{\circ}C$이상의 반응온도에서는 활성저하가 관찰되지 않아 본 연구에서 제조된 촉매는 $300^{\circ}C$이상의 온도에서 조업되는 것이 바람직하다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.4
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• pp.313-320
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• 2018

In the spring of 2018, opened-flowers of fruit trees were frozen to death due to abnormal low temperature around Jeonbuk Province and southern Gyeonggi Province areas. In the 2000s, abnormal weather is observed all over the world very frequently. As a consequence, various sectors of the society suffer from economic damage and negative effects of the abnormal weather. Moreover, recent global climate change is believed to increase the incidence of extreme weathers, which are out of the normal range of the local climate. It is necessary to identify these abnormal weather phenomena accurately and analyze the effects of them on crops in order to understand the effects of them on crop yields. This study projected the trend of the low-temperature occurrence in the future by predicting the changes in future flowering dates and quantifying the temperature distribution after flowering using climate change scenarios. This study targeted areas actually producing a major portion of pear, peach, and apple in South Korea. The results of this study predicted that the flowering dates of these fruits will be approximately 20 days earlier than the current normal year in the future (2071-2100) for the study area. Moreover, it was found that the distribution of low temperature would vary by fruit type and region to some degree. The results of this study present only a portion of fruit trees cultivars grown in South Korea. It was expected that, when this approach is applied to various crops and fruit trees, it will be possible to contribute to preparing countermeasures for climate change in the agricultural sector.