• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2017.04a
• /
• pp.79-79
• /
• 2017

국내 여름철의 고온다습한 기후환경으로 인하여 온실 내부의 냉방 및 제습이 필수적인데, 온실 냉방 방식 중 증발냉각 시스템이 가장 효율이 높다고 알려져 있다. 하지만 증발냉각 시스템은 건조한 기후 지역에서 발달한 방식으로, 작물의 증산작용으로 인한 온실 내부 습도 상승에 따른 문제점이 발생되어 다습한 여름철 국내 기후에는 반드시 냉각과 제습이 동시에 필요하다. 따라서 증발냉각 방식 중 Fan and Pad 방식과 리튬브로마이드 수용액을 이용한 온실 냉방 및 제습을 위한 복합시스템에 관한 연구가 진행중이다. 현재 리튬브로마이드 수용액 제습 시 발생되는 발열량과 수용액의 무게변화와 같은 수용액의 흡습성질 대한 정확한 지표가 나타나 있지 않다. 이에 연구를 진행하기에 앞서 리튬브로마이드 흡습성질에 관한 데이터 자료가 필요하다고 판단되어 기초실험을 진행하였고, 본 연구에서는 Pilot Scale의 재생 순환시스템을 통해 리튬브로마이드 수용액의 흡습성질을 이용한 재사용 방안을 제시하였고, 시스템 내에서 외부투입공기와 작동유체의 흡습성질에 의한 반응 전후 온도변화 예측 모델을 수립하였다. 따라서 본 연구를 통해 리튬브로마이드 수용액의 흡습성질을 분석하고, 이를 이 용한 재생 순환 시스템에 관한 연구를 진행할 예정이다.

• Journal of Applied Biological Chemistry
• /
• v.54 no.3
• /
• pp.214-217
• /
• 2011

Fumigant, methyl bromide which is used in most countries for plant quarantine, has been designated and under control as ozone depleting substance. For developing alternative chemicals for methyl bromide, many countries have been intensifying their capacity. This study was carried out to investigate the residue patterns of hydrogen cyanide which is commonly used for plant quarantine. Hydrogen cyanide was treated onto the orange, banana, and pineapple at recommended and double doses and then sampling was done at 1 and 3 day after fumigation treatment. Residue of hydrogen cyanide was found safe because average residue levels on orange, banana, and pineapple after 3 days of fumigation treatment were $0.57{\pm}0.05$, $0.21{\pm}0.17$, and $0.41{\pm}0.08$ ppm, which were lower than the MRLs of Korea (5 ppm), Japan (5 ppm), USA (50 ppm), and Canada (25 ppm). Hydrogen cyanide are expected to be used as alternative chemicals for methyl bromide fumigant for orange, banana, and pineapple.

• Journal of Bio-Environment Control
• /
• v.23 no.4
• /
• pp.337-341
• /
• 2014

Due to the nature of the ambient air temperature in summer in korea, the growth of crops in greenhouse normally requires cooling and dehumidification. Even though various cooling and dehumidification methods have been presented, there are many obstacles to figure out in practical application such as excessive energy use, cost, and performance. To overcome this problem, the lab scale experiments using lithium bromide(LiBr) solution and cooling coil for dehumidification and cooling in greenhouses were performed. In this study, preliminary experiment of dehumidification and cooling for the greenhouse was done using LiBr solution as the dehumidifying materials, and cooling coil separately and then combined system was tested as well. Hot and humid air was dehumidified from 85% to 70% by passing through a pad soaked with LiBr, and cooled from 308K to 299K through the cooling coil. computational Fluid Dynamics(CFD) analysis and analytical solution were done for the change of air temperature by heat transfer. Simulation results showed that the final air temperature was calculated 299.7K and 299.9K respectively with the deviation of 0.7K comparing the experimental value having good agreement. From this result, LiBr solution with cooling coil system could be applicable in the greenhouse.

• Applied Chemistry for Engineering
• /
• v.10 no.6
• /
• pp.960-962
• /
• 1999

Organically modifidied montmorillonites were synthesized from sodium montmorillonite and alkylammonium halids (stearyltrimethyl bromide and cetyltrimethyl bromide) by solid-solid reaction. The structure of the products by solid-solid reactions was similar to that observed in a conventional solution method.

• 산림경영
• /
• s.148
• /
• pp.54-55
• /
• 2001

산림청 임업연구원(원장 서승진)은 몬트리올의정서에서 오존층 파괴물질로 지정되어 2005년부터 세계적으로 사용이 금지되게 되는 훈증농약인 메틸브로마이드(Methyl Bromide : MB)를 대체할 수 있는 훈증활성물질 이소치오시아네트(Isothiocyanate)를 양고추냉이(겨자무)로부터 추출하는데 성공하였다. 메틸브로마이드는 세계적으로 토양소득, 검역, 시설물 훈증에 약 7만톤이 사용되는 유독성 물질로서 대체물질 개발을 위해 여러나라에서 연구 중에 있으며 우리나라도 OECD 가입국으로서 환경친화적 무공해 농약의 개발이 시급한 실정이었다. 이소치오시아네이트는 쌀, 옥수수, 콩 등 각종 곡물에 피해를 주는 쌀바구미, 팥바구미, 화랑곡나방, 권연벌레 등 저장곡물해충에 메틸보로마이드와 대등한 살충효과가 있는 무공해 천연물로서 메틸브로마이드를 대체할 수 있을 것으로 전망하고 있다. 앞으로 제형개발 등 상품화가 되면 수입에 의존하고 있는 저장곡물 방충농약을 대체할 수 있어 연간 300만 달러의 외화 절감은 물론 지구환경파괴를 막을 수 있는 획기적 계기를 마련하였다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 1994.05a
• /
• pp.103-108
• /
• 1994

리튬브로마이드 수용액이 수직관내면을 따라 액막의 형태로 흘러 내릴때 수증기와의 흡수과정에 대하여 열 및 물질전달 특성을 실험하였다. 실험에서 열 및 물질전달계수는 막레이놀즈수를 30에서 200까지 변화시키면서 실시하였다. 일정한 냉방능력에서 시스템 압력을 변화시켰을 때의 열 및 물질전달계수를 측정하였다. 액막의 열전달계수는 레이놀즈수가 증가함에 따라 감소하였다. 최대 질량유량에서 최적의 막레이놀즈수가 존재하였다.

• Korean Journal of Environmental Biology
• /
• v.39 no.3
• /
• pp.354-361
• /
• 2021

Understanding the phytotoxic mechanism of methyl bromide (MB), an essential fumigant during the quarantine and pre-shipment process, is urgently needed to ensure its proper use and reduce international economic losses. In a previous study, two main MB-induced toxic mechanisms such as reactive oxygen species (ROS) and auxin distribution were selected by analyzing transcriptomic analysis. In the study, a 3-week-old A. thaliana was supplied with 1 mM ROS scavengers [N-acetyl-L-cysteine (NAC) or L-glutathione (GSH)] and 1µM indole-3-acetic acid(IAA) three times every 12 h, and visual and gene expression assessments were performed to evaluate the reduction in phytotoxicity by supplements. Phytotoxic effects on the MB-4h exposed group were decreased with GSH application compared to the other single supplements and a combination of supplements at 7 days post fumigation. Among these supplements, GSH at a concentration of 1, 2, and 5mM was suppled to A. thaliana with MB-fumigation. During a long-term observation of 2 weeks after the fumigation, 5 mM GSH application was the most effective in minimizing MB-induced phytotoxic effects with up-regulation of HSP70 expression and increase in main stem length. These results indicated that ROS was a main key factor of MB-induced phytotoxicity and that GSH can be used as a supplement to reduce the phytotoxicity of MB.

• 월간산업보건
• /
• s.283
• /
• pp.5-9
• /
• 2011

• 월간산업보건
• /
• s.333
• /
• pp.59-63
• /
• 2016

• Analytical Science and Technology
• /
• v.11 no.2
• /
• pp.88-91
• /
• 1998

Bromide($Br^-$) was separated and quantified with $2.8mM-NaHCO_3/2.2mM-Na_2CO_3$ by Ion Chromatography. Bromide was eluted at 8.9 min. and the detectetion limit was 2.5 ng. We compared with bromide concentration in normal or methylbromide intoxicated bloods and tissues. Bromide concentrations were 2.0~5.8 ppm in normal bloods and 1.0~5.3 ppm in normal tissues. In fatal cases of methylbromide intoxication, blood bromide concentrations (4 cases) of 74.2~139 ppm and tissue bromide concentration (1 case) of 76 (heart)~201 (lung) ppm were detected. In fatal cases, blood bromide concentrations. were 12~22 times higher than those of normal bloods.