• 한국유기농업학회지
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• 제19권spc호
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• pp.234-237
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• 2011

This study was carried out to investigate the effect of soil covering materials such as rice bran, rice hull and saw dust on garlic growth through a field experiment in wintertime. Rice bran was the smallest in term of particle size, but it recorded the highest level of bulk density. The missing plant rate after winter season was relatively high, 59.3%, and that of soil covering materials stood at the low level of 10%. Other growth factors recorded the highest level during application of rice bran. In terms of chemical properties of soil-covering materials, rice bran recorded the highest level of 1.84, 2.34 and 0.16% in the content of N, P, and K, respectively. The subsoil temperature was higher by application of rice bran as compared to that of other materials which stood at the lowest temperature ($-9^{\circ}C$).

• 한국광물학회지
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• 제28권2호
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• pp.165-171
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• 2015

부산과 울산의 중심지역에 대해 공기 중의 분진시료를 채취하여, 위상차현미경, 위상차분산현미경, 주사전자현미경 등으로 석면을 분석한 결과, 석면은 검출한계 이하로서 확인되지 않았다. 공기중의 분진시료에는 섬유상물질이 다수 포함되었으나, 이들은 대부분 유기질 섬유인 것으로 나타났다. 무기질 섬유물질로는 암면, 세라믹섬유, 석고 등이 소량 포함되었으며, 비섬유상인 석영, 방해석, 장석등의 광물도 가끔 관찰되었다. 국내의 공기 중 분진의 석면분석은 주로 위상차현미경으로 관찰하는 것으로 규정되어 있으나, 이것만으로는 석면의 식별이 불가능한 것으로 나타났다. 따라서 일본 JIS법과 같이 저온회화 처리 장치에 의한 유기물질 제거 후에 분산염색법으로 석면을 식별하고 계수하는 것이 효율적인 것으로 사료된다.

• 한국입자에어로졸학회지
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• 제9권2호
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• pp.89-102
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• 2013

24-hr $PM_{2.5}$ samples were collected from January 19 through February 27, 2009 at an urban site of Gwangju and analyzed to determine the concentrations of organic and elemental carbon(OC and EC), water-soluble OC(WSOC), eight ionic species($Na^+$, $NH^{4+}$, $K^+$, $Ca^{2+}$, $Mg^{2+}$, $Cl^-$, ${NO_3}^-$ and ${SO_4}^{2-}$), and 22 elemental species. Haze phenomena was observed during approximately 29%(10 times) of the whole sampling period(35 days), resulting in highly elevated concentrations of $PM_{2.5}$ and its chemical components. An Asian dust event was also observed, during which $PM_{2.5}$ concentration was 64.5 ${\mu}g/m^2$. Crustal materials during Asian dust event contributed 26.6% to the $PM_{2.5}$, while lowest contribution(5.1%) was from the haze events. OC/EC and WSOC/OC ratios were found to be higher during haze days than during other sampling days, reflecting an enhanced secondary organic aerosol production under the haze conditions. For an Asian dust event, enhanced concentrations of OC and secondary inorganic components were also found, suggesting the further atmospheric processing of precursor gases during transport of air mass to the sampling site. Correlations among WSOC, EC, ${NO_3}^-$, ${SO_4}^{2-}$, and primary and secondary OC fractions, which were predicted from EC tracer method, suggests that the observed WSOC could be formed from similar formation processes as those of secondary organic aerosol, ${NO_3}^-$ and ${SO_4}^{2-}$. Results from principal component analysis indicate also that the observed WSOC was strongly associated with formation routes of the secondary organic and inorganic aerosols.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제33회 KOSCO SYMPOSIUM 논문집
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• pp.42-45
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• 2006

A new and reusable energy source is water-treatment sludges. There is a significant need for understanding the characteristics of sludge combustion related to improving efficiency and ensuring the safety of this new energy source. Because sludges are composed of solids and gas mixture, the combustion of the mixture may become quite complex. Not only decomposition of conventional organic elements but also dust explosion may be important during the process of converting sludges into a new and safe form of energy. Sludge combustion mainly involves hydrogen, methane, hydro carbons, carbon, and organic particles. Dust explosion during the gasification stage may depend on the surrounding temperature and the composition of gases. The uncertainty in the explosive behavior of energetic source is noted in this work. We study the explosion characteristics of sludge combustion while the reusability of sewage sludges as a new form of energy is also investigated.

• Journal of Korean Society for Atmospheric Environment
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• 제17권E4호
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• pp.145-155
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• 2001

Simple mass balance method was developed to estimate the contribution of two major fugitive dust sources in the Port of Incheon to a nearby residential area in this study. Using the relatively small number of TSP data as well as the data on mass fraction of Fe and organic materials in the sampled dust, our simplified method demonstrated its ability to estimate the contribution of each fugitive source to a specific location including the residential area with relatively reasonable accuracy. It is clear from this simple method can be applied to the situation where two major fugitive dust sources are responsible for the high TSP concentration around the source area and there are clear marker chemicals representing the characteristics of the fugitive dust sources.

• 한국산업보건학회지
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• 제30권3호
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• pp.292-298
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• 2020

Objectives: The aim of this research is to establish Similar Exposure Groups (SEGs) for chemical and biological risk factors that occur in farm work involving 24 tasks among 15 crops. Methods: To categorize SEGs, work type, work environment, and similar tasks for each crop were considered. After confirming the chemical risk factors (pesticides, inorganic dust-total dust and PM₁₀, ammonia, and hydrogen sulfide) and biological factors (organic dust-total dust and PM₁₀, and endotoxins) that occur in the crops and tasks, similar crops and tasks were selected as SEGs. Results: Among chemical risk factors, pesticides was selected for the SEGs, which was categorized by open field, greenhouse, fruit, and specialty crops. For inorganic dust, open field (plowing harrowing, seedling, planting, harvest, and sorting and packing) and specialty crops (plowing harrowing, seedling, planting, and harvest) were selected as SEGs. For ammonia and hydrogen sulfide, livestock (preparation of farm, management of nursery bed, feeding, shipment and manure treatment) were selected as SEGs. For biological risk factors such as organic dust (total dust, PM₁₀) and endotoxins, open field (manure application), greenhouse (plowing harrowing, planting, manure application, and harvest), fruit (manure application), specialty crops (manure application, making furrows, mixing mushroom media, harvest, and sorting and packing), and livestock (preparation of farm, maintaining poultry litter, feeding, shipment and manure treatment) were selected as SEGs. Conclusions: To establish similar exposure groups in agriculture, it is important that the characteristics of each hazard factor are categorized by identifying risk factors occurring by tasks.

• International Journal of Safety
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• 제11권1호
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• pp.15-18
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• 2012

Because of development of printing technology, toner cartridge particle becomes smaller and more dangerous. And sometimes we had incidents with dust explosion of toner cartridge particle at recycling facilities in Japan. Therefore we studied on hazard of toner particle relating with dust explosion. We found that toner particle is so dangerous compared with most organic solids, even though it does not belong to hazardous materials in the UN regulation and the Japanese Fire Service Law.

• 유기물자원화
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• 제18권1호
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• pp.66-72
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• 2010

본 연구는 경기도 A지역 자원회수시설에서 연소온도의 변화에 따른 NOx, SOx, CO, HCL, DUST의 발생변화와 보일러 배출가스 온도, 보일러 출구산소 농도, 반건식 반응탑 출구온도, 촉매탑온도, 배출가스 온도의 변화를 분석하였다. SOx, CO, Hcl, DUST는 자원회수시설 내의 연소온도가 상승함에 따라 거의 5 ppm 미만의 일정한 값을 유지한 반면 NOx 는 40 ppm에서 70 ppm으로 증가하는 추세였다. 한편 보일러 배출가스 온도와 촉매탑 온도는 일정치를 유지하였으나 보일러 출구의 산소농도는 조금씩 감소하는 결과를 나타내었다.

• 원예과학기술지
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• 제33권5호
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• pp.751-762
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• 2015

본 연구는 평면형 바이오필터를 설계하여 제작하고 이 바이오필터에 디펜바키아(Dieffenbachia amoena 'Marianne')의 식재 여부에 따라 환기 용량을 제어할 수 있는 토양 수분 안정화 정도를 측정하고 미세먼지, 휘발성 유기화합물 및 포름알데히드(HCHO)와 같은 실내공기 오염물질에 대한 바이오필터의 제거율을 비교하였다. 실험 결과 디펜바키아의 식재 여부에 관계없이 모두 일정한 상대습도, 온도 및 토양 수분 함량을 나타내었고 이 바이오필터에 식재한 디펜바키아도 정상적으로 생육하였다. 바이오필터에 의한 미세먼지 제거율을 보면, 미세먼지(PM10)와 초미세먼지(PM2.5)의 입자 수는 토양만 있는 경우 각각 30%와 2% 이상 제거되었고, 디펜바키아를 식재한 경우도 각각 40%와 4% 이상 제거되었다. 미세먼지(PM10) 무게에 따른 제거율은 토양만 있는 경우 4% 이상, 디펜바키아를 식재한 경우 20% 이상으로 나타났다. 토양만 채운 바이오필터는 xylene, ethylbenzene, toluene, total volatile organic compounds(T-VOCs)를 63% 이상 제거하였으나 benzene은 22% 이상, HCHO는 38% 이상을 제거하였다. 디펜바키아를 식재한 바이오필터는 xylene, ethylbenzene, toluene, T-VOCs를 72% 이상 제거하였고 benzene과 HCHO도 39% 이상 제거하였다. 따라서 식물과 바이오 필터를 결합한 시스템은 미세먼지의 제거보다 휘발성 유기 화합물의 제거에 대한 효과가 더 높은 것으로 나타났다. 본 연구에서 제작한 평면형 바이오필터는 실내 공기질 정화에 매우 효과가 있는 것으로 나타났으며, 식물과 바이오필터를 결합하였을 때 그 효과는 더욱 큰 것으로 확인하였다.

• 한국약용작물학회지
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• 제6권1호
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• pp.16-20
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• 1998

유기물(有機物) 시용(施用)에 따른 전호(前胡) 뿌리 의 조단백질(粗蛋白質), 조지방(粗脂肪), 조섬유(粗纖維), 조회분(粗灰分) 등(等) 성분(成分)과 정유성분(精油成分)의 변화(變化)에 대한 실험(實驗)을 통하여 얻어진 결과(結果)를 요약(要約)하면 다음과 같다. 1. 초장(草長)은 대조구(對照區)인 단비(單肥)보다 볏집 퇴비(堆肥), 활엽수(闊葉樹) 퇴비(堆肥) 및 산야초(山野草) 퇴비(堆肥)에서는 다소 짧은 경향(傾向)을 보였으나 계분(鷄糞)톱밥 퇴비(堆肥)에서 가장 길었고. 10a 당(當) 근수량(根收量)은 단비(單肥) 165kg보다 계분(鷄糞)톱밥 퇴비(堆肥)에서 276kg으로 가장 높았고 산야초퇴비(山野草堆肥) 193kg, 활엽수(闊葉樹) 퇴비(堆肥) 188kg이었으나 볏짚 퇴비(堆肥)는 148kg으로 가장 낮았다. 2. 계분(鷄糞)톱밥 퇴비(堆肥) 시용구(施用區)에서 조단백질(粗蛋白質) 7.36 %, 조지방(粗脂肪) 5.57%, 조섬유(粗纖維) 2.89%로 단비(單肥) 및 기타 퇴비시용구(堆肥施用區)보다 현저(顯著)히 높게 나타났다. 3. 식물(植物) 정유(精油) 함량(含量)은 계분(鷄糞)톱밥 퇴비(堆肥)에서 0.82%로 가장 높았다. 4. 향기(香氣) 성분(成分)의 조성(組成)은 특(特)히 sabinene과 carboxaldehyde의 2개(個) 성분(成分)이 단비(單肥)에서 각각(各各) 14.4, 120.3 % area였으나 계분(鷄糞)톱밥 퇴비(堆肥)에서는 16.9, 163.4% area로 높게 나타났다.