• 한국환경복원기술학회지
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• 제9권5호
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• pp.32-40
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• 2006

This study's objects are to suggest effective forest community-level management measures by identifying the vulnerable forest vegetation communities types to climate change through a comparative analysis with present forest communities identified and delineated in the Actual Vegetation Map. The methods of this study are to classify the climatic life zones based on the correlative climate-vegetation relationship for each forest vegetation community, the Holdridge Bio-Climate Model was employed. This study confirms relationship between forest vegetation and environmental factors using Pearson's correlation coefficient analysis. Then, the future distribution of forest vegetation are predicted derived factors and present distribution of vegetation by utilizing the multinomial logit model. The vulnerability of forest to climate change was evaluated by identifying the forest community shifts slower than the average velocity of forest moving (VFM) for woody plants, which is assumed to be 0.25 kilometers per year. The major findings in this study are as follows : First, the result of correlative analysis shows that summer precipitation, mean temperature of the coldest month, elevation, soil organic matter contents, and soil acidity (pH) are highly influencing factors to the distribution of forest vegetation. Secondly, the result of the vulnerability assessment employing the assumed velocity of forest moving for woody plants (0.25kmjyear) shows that 54.82% of the forest turned out to be vulnerable to climate change. The sub-alpine vegetations in regions around Mount Jiri and Mount Seorak are predicted to shift the dominance toward Quercus mongolica and Pinus densiflora communities. In the identified vulnerable areas centering the southern and eastern coastal regions, about 8.27% of the Pinus densiflora communities is likely to shift to sub-tropical forest communities, and 3.38% of the Quercus mongolica communities is likely to shift toward Quercus acutissima communities. In the vulnerable areas scattered throughout the country, about 8.84% of the Quercus mongolica communities is likely to shift toward Pinus densiflora communities due to the effects of climate change. The study findings concluded that challenges associated with predicting the future climate using RCM and the assessment of the future vulnerabilities of forest vegetations to climate change are significant.

• 한국산업보건학회지
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• 제9권1호
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• pp.23-40
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• 1999

The analysis of thiodiglycolic acid in urine has been used as an index of biological exposure to vinyl chloride. Unfortunately thiodiglycolic acid has a strong hydrophilic character, because it has two carboxylic groups, so that it can only be extracted with organic solvent with a great difficulty. Underivatized thiodiglycolic acid tends to tail because of non-specific interaction with the inert support. Therefore, esterification is the obvious first choice for derivatization of thiodiglycolic acid, particularly for gas chromatography. In this study, the focus of interest is to compare two method of esterifications (methylation and silylation). Methylation is to make the methyl ester of thiodiglycolic acid by reaction with diazomethane. Silylation is to make the trimethylsilyl ester of thiodiglycolic acid by reaction with N-trimethylsily-ldiethylamine. The results and conclusions are as the following: 1. The detection limit (sensitivity) of methylated thiodiglycolic acid was $5.00{\mu}g/m{\ell}$ and silylated thiodiglycolic acid was $3.07{\mu}g/m{\ell}$ by gas chromatography with flame ionization detector. 2. The optimal liquid-liquid extraction of thiodiglycolic acid was as following: To each of the tubes, $15m{\ell}$ of urine, concentrated sulfuric acid (pH 1 - 2) and 5 gsodium sulfate were added. The samples was extracted three times with $5m{\ell}$ ethylacetate each time. 3. The methylated thiodiglycolic acid was more stable than silylated thiodiglycolic acid in extractional solvent which contained humidity. 4. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.07324 in methylated thiodiglycolic acid with external standard calibration, and 0.07033 in methylated thiodiglycolic acid with internal standard calibration. 5. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.10914 in silylated thiodiglycolic acid with external standard calibration, and 0.13602 in silylated thiodiglycolic acid with internal standard calibration. From the above results, the analysis of methylated thiodiglycolic acid was more sensitive (limit of detection) than silylated thiodiglycolic acid by gas chromatography. However, the methylated thiodiglycolic acid was stable in the humidity and was separated sharply on chromatogram. Also, analysis of methylated thiodiglycolic acid was more precise (pooled coefficient of variation for 4 days) than silylated thiodiglycolic acid. In conclusion, it is established that the analysis of methylated thiodiglycolic acid is appropriate for biological monitoring of exposure to vinyl chloride.

• 한국식품과학회지
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• 제42권4호
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• pp.390-397
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• 2010

Residual solvents in foods are defined as organic volatile chemicals used or produced in manufacturing of extracts or additives, or functional foods. The solvents are not completely eliminated by practical manufacturing techniques and they also may become contaminated by solvents from packing, transportation or storage in warehouses. Because residual solvents have no nutritional value but may be hazardous to human health, there is a need to remove them from the final products or reduce their amounts to below acceptable levels. The purpose of this study was to develop and evaluate an analytical method for the screening of residual solvents in health functional foods. Furthermore, the aim of this study was to constitute a reasonable management system based on the current state of the market and case studies of foreign countries. Eleven volatile solvents such as MeOH, EtOH, trichloroethylene and hexane were separated depending on their column properties, temp. and time using Gas Chromatography (GC). After determining the GC conditions, a sample preparation method using HSS (Head Space Sampling) was developed. From the results, a method for analyzing residual solvents in health functional foods was developed considering matrix effect and interference from the sample obtained from the solution of solvents-free health functional foods spiked with 11 standards solutions. Validation test using the developed GC/HSS/MS (Mass Spectrometry) method was followed by tests for precision, accuracy, recovery, linearity and adequate sensitivity. Finally, examination of 104 samples grouped in suits was performed by the developed HSS/GC/MS for screening the solvents. The 11 solvents were isolated from health functional foods based on vapor pressure difference, and followed by separation within 15 minutes in a single run. The limt of detection (LOD), limit of quantification (LOQ), recovery and coefficient of variation (C.V.) of these compounds determined by the HSS/GC/MS were found to be 0.1 pg/mL, 0.1-125 pg/g, 51.0-104.6%, and less than 15%, respectively. Using the developed HSS/GC/MS method, residual solvent from 16 out of 104 health functional products were detected as a EtOH. This method therefore seems t o be a valuable extension ofanalytical method for the identification of residual solvents in health functional food.

• 생태와환경
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• 제33권3호통권91호
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• pp.251-259
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• 2000

금강 하구호의 수질 특성을 파악하기 위하여 1998년 1월부터 1999년 9월까지 매월 조사하였다. 수질 인자 중 TN, TP, chl-a 및 투명도의 평균값은 각각 3,900 ${\mu}$g N/l, 160 ${\mu}$g P/l, 73 ${\mu}$g/l 및 0.8m로서 부영양화 특성이 잘 나타났다. TN 중에서 유기질소가 66%, 무기질소가 34%를 차지하였고 무기질소 중에서 NH$_{4}$와 NO$_{3}$는 각각 30%와 70%를 점유하였다. 또한 TP에 대한 SRP의 비율은 9% 이하였다. TN/TP 및 DIN/SRP비는 겨울에 높고 여름에 낮았다. SRSi는 0${\sim}$3.0 mg Si/l 범위로 변동 폭이 컸고 하계에 매우 높았으며 SRSi가 장기간 고갈되는 양상도 관찰되어 SRP와 더불어 담수조류(규조류)의 생장에 영향을 줄 수 있는 제한영양염으로 추정되었다. Chla는 동${\cdot}$하계에 각각 113 ${\mu}$g/l, 162 ${\mu}$g/l로서 월등히 높았고 이 시기는 규조류 Stephanodiscus와 남조류 Microcystis가 번무하는 시기였다. 하구 저수지의 수질오염도는 과영양상태로 평가되어 이에 대한 수질관리가 매우 시급한 것으로 판단되었다.

• 한국화재소방학회논문지
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• 제31권6호
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• pp.107-111
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• 2017

본 연구는 흡연시 발생되는 각종 유해오염물질을 효과적으로 저감할 수 있는 친환경 흡연부스를 제작하고, 유해물질의 제거효율 및 효과를 평가하는 것이다. 유입구-HEPA필터-전기집진기(EP)-첨착활성탄-배출구 등의 탈취설비를 갖춘 친환경 자동 흡연부스를 설계 및 제작하여, 흡연연기에 의한 유해오염물질의 제거효율을 측정 및 평가하였다. 측정방법으로는 내부의 배경농도, 설비 가동 시 배출구 농도, 10분 후 흡연부스의 농도를 측정하고, 평가항목으로는 복합악취, 일산화탄소, 미세먼지($PM_1$, $PM_{2.5}$, $PM_{10}$), 총휘발성유기화합물(TVOCs)을 대상으로 하였다. 복합악취 제거효율은 흡연부스 내부에서는 95.37%, 방지설비통과 배출구에서는 97.38%로 우수하였다. 일산화탄소 제거효율은 내부에서는 94.25%, 배출구에서는 98.32%로 나타났다. 또 흡연부스 내부에서의 미세먼지 제거효율은 98.59%이며, 배출구에서는 98.85%로 나타나 미세먼지 제거효율은 매우 우수한 것으로 나타났다. TVOCs는 흡연부스 내부에서는 $26,000{\mu}g/m^3$에서 $5,203{\mu}g/m^3$로 감소하여 79.99%의 제거효율로 나타났고, 환풍기 가동 후 방지설비 배출구에서는 $5,019{\mu}g/m^3$로 측정되어 제거효율은 80.70%로 나타났다. 따라서 본 연구를 통하여 제작, 설계된 흡연부스는 향후 소규모 작업환경 내에서도 각종 유해오염물질들을 제거하는 용도로 적용할 수 있을 것으로 생각된다.

• 한국토양비료학회지
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• 제30권3호
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• pp.272-279
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• 1997

시설재배지(施設栽培地)의 토양비옥도(土壤肥沃度) 관리(管理)를 위한 기초자료(基礎資料)를 얻고자, 우리나라 남부지방(南部地方)에 위치한 시설과채류(施設果菜類) 및 화훼류(花卉類) 주산지(主産地) 71개 포장의 토양화학성(土壤化學性)과 작물(作物)의 양분함량(養分含量)을 분석한 결과는 다음과 같았다. 1. 토양(土壤)의 화학성(化學性)은 평균적(平均的)으로 볼 때 pH와 유기물(有機物), 붕소(硼素), 망간, 아연 등(等)이 적정수준(適正水準)을 보였고, 유효인산(有效燐酸)과 치환성(置換性) 양(陽)이온은 과다집적(過多集積)된 경향이었다. 특히 유효인산(有效燐酸)은 연작년수(連作年數)와 고도(高度)의 정상관(正相關)($r=0.50^{**}$, 표토 ; $0.42^{**}$, 심토)을 보였다. 그리고 염기비(鹽基比)는 Ca/Mg가 2.7~2.8, Ca/K는 5.1~5.5, Mg/K는 1.7(표토)~2.0(심토)이었다. 2. 시설재배지(施設栽培地) 표토(表土)에서의 인산함량(燐酸含量)은 912(부산)~1796mg/kg(마산)이었고 칼리는 1.52(부산)${\sim}2.93cmol^+/kg$(순천), 석회는 7.44(마산)${\sim}18.58cmol^+/kg$(창원), 고토는 2.82(창녕)${\sim}6.24cmol^+/kg$(창원) 범위였다. 그리고 pH 증가(增加)에 대하여 석회는 칼리나 고토와 달리 정상관(正相關)($r=0.253^*$)의 영향을 끼쳤다. 3. 식물체(植物體)의 인함량(燐含量)은 고추와 오이, 피망, 장미, 국화, 카네이션 모두에서, 칼리는 장미 외의 작물(作物)에서 각각 높았다. 그리고 석회와 고토는 화훼류(花卉類)보다 과채류(果菜類)에서 2배 이상(以上) 높았으며 칼리와는 길항적(拮抗的) 흡수관계(吸收關係)를 보였다.

• 한국토양비료학회지
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• 제48권3호
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• pp.194-204
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• 2015

Six study sites in Gumi, Goryeong in Gyeongbuk province and Naju in Jeonnam province were selected to investigate soil properties of poorly drained horizons in paddy soils. The horizons were re-established layers which were parent material layers originated from fluvial deposits. Topsoil layers were differentiated from piled parent materials while soil structure of the topsoil layer was massive with striated microstructure. Compaction at soil re-establishment and a lack of structure and aggregate development in these soils may cause the limitation of vertical water movement and result in poorly drained horizons. Soil samples were taken from paddy fields with top soils of sandy loam, silt loam and silty clay loam and re-established soils of coarse and fine texture. The samples were taken from each horizon for the analyses of soil chemical and mineral properties. Soils with re-established soils of coarse texture had greater amounts of sands from top soil texture distributions, while soils with fine texture had greater amounts of silts. Chemical properties of top soils were analyzed from rice cultivated soils at the time of re-establishments and one year after the re-establishments. The coarse texture of the re-established horizons decreased in EC values from 0.23 to $0.11(dS\;m^{-1})$, available phosphate values from 112 to $54(mg\;kg^{-1})$, and exchangeable Ca values from 6.6 to $4.9(cmol_c\;kg^{-1})$. On the other hand, soils with fine texture showed decrease only in pH and exchangeable Ca values. Especially, organic matter and available phosphate contents showed heterogeneous distributions from each horizon. This result may be caused by mixture of plough layer and subsurface layer during and consolidation. Hydraulic conductivity values were low at the boundaries of top soil and parent material layers except SL/coarse soil. Soil microstructure was massive structure without soil clods or pores and showed striated structure. Therefore, re-established paddy fields with fluvial deposits as parent material layers showed limited vertical movements of soil water because of occurrence of compacted layers and less-development of soil clods and aggregates.

• Weed & Turfgrass Science
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• 제4권3호
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• pp.262-267
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• 2015

잔디 뗏장의 효율적인 생산과 토양 관리 시스템을 구축하고 재배방법을 개선하기 위한 기초 데이터를 제공하기 위해, 토양환경에 따른 잔디의 생육상태에 대한 연구를 수행 할 필요가 있다. 본 연구는 뗏장 생산의 재배기간에 따른 잔디의 생육과 토양 화학적 특성을 조사하기 위해 뗏장 재배기간이 1년, 10년, 20년, 그리고 30년 된 지역을 각각 조사하였다. 재배기간이 장기화됨에 따라, 토양 용적밀도는 증가하였고, 공극률과 기상은 감소하였다. pH는 30년 동안 재배된 곳에서 가장 높았고, 전질소와 유기물의 함량은 1년 동안 재배된 토양에서 가장 높았다. 결과적으로, 토양 화학적 특성은 1년 재배된 토양에서보다 계속적인 재배 토양에서 악화되었다. 잔디의 재배기간이 길어짐에 따라 지상부와 지하부의 생육이 감소하였다. 그러므로 계속적인 잔디 뗏장 생산 재배로 인한 토양 악화가 잔디의 품질과 생장을 감소시키므로, 10년 이상 연작된 지역에서는 토양 갱신을 통해 잔디생육을 향상시켜야 한다.

• Weed & Turfgrass Science
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• 제4권3호
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• pp.243-248
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• 2015

본 연구는 수수 지상부 부산물을 이용하여 제초활성을 검정하며 생물제초제로서의 개발 가능성을 알아보고자 수행되었다. 수수 지상부 분말을 토양과 혼합하여 처리했을 때 피, 바랭이, 어저귀, 털비름의 발아 억제율은 최대 40% 정도였으며 발아한 개체들의 지상부 생육억제율은 광엽잡초인 어저귀와 털비름에서 최대 30%, 화본과잡초인 피와 바랭이에서는 30% 이하로 낮게 나타났다. 수수 지상부 추출물의 발아억제 효과는 피를 제외한 바랭이, 어저귀, 털비름에서는 $25mg\;ml^{-1}$ 이상의 농도에서 크게 나타났으며, 50%의 발아를 저해하는 농도가 피에서는 $60mg\;ml^{-1}$였으나 나머지 세 초종에서는 $1060mg\;ml^{-1}$ 이하로 작게 나타났다. 경엽처리활성을 높이기 위해 선발한 11개 전착제 중 DOS70, TM15, TDE7이 가장 효과적인 것으로 나타났으며, 그 중 DOS70는 주요 잡초종을 60%까지 방제할 수 있었다. 비록 수수 지상부 부산물의 잡초방제효과가 크지는 않은 것으로 나타났지만 장기적인 처리에 의한 잡초종자 및 개체밀도의 점진적인 경감이 기대된다.

• 한국산업보건학회지
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• 제16권2호
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• pp.131-144
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• 2006

For the purpose of preparing the fundamental data on working environment of small scale manufacturing industries and preventing the occupational diseases of workers in these industries, authors surveyed the status of working environment to several chemical substances and physical agents by types of industry and types of process in the small scale manufacturing industries with less than five workers in Gimhae including 235 workplaces, 14 types of industry and 25 types of process from January 2002 to December 2004. This measurement method was work environment measurement method (established in Ministry of Labor, Korea), analytical methods (2nd Ed.) of Occupational Safety and Health Administration (OSHA) and manual of analytical methods (4th Ed.) of National Institute for Occupational Safety and Health (NIOSH) and collected data was analyzed by using SPSS 10.0 for windows, the results were as follows: 1. Noise generated in 14 types of industry and 22 types of process. an actual level of mean exposure (90.7 dB(A)) exceeded threshold limit values (TLVs) in manufacture of other transport equipment. An actual level of mean exposure (90.2dB) exceeded TLVs in the process of wire-drawing and 90.4dB in the process of wire-stranding. 2. Dusts of type I, II, III were generated in 9 types of industry and 8 types of process. Its mean concentration did not exceed TLVs. 3. Heavy metals (Pb, Mn, Cr, Ni) were generated in 7 types of industry and 7 types of process. Its mean concentration did not exceed TLVs. 4. 16 kinds of organic solvents were generated in 11 types of industry and 6 types of process. Its mean concentration did not exceed TLVs. As the above results, chemical substances and physical agents were generated in the several different types of industry and process of the manufacturing industry with less than five workers, and only mean level of noise was exceeded TLVs. In case of exceeding threshold limit values, improvement of work environment is actively needed, and work environment management should be performed continuously for prevention of an occupational diseases and work related diseases.