• 해양환경안전학회지
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• 제18권2호
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• pp.101-114
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• 2012

본 연구는 2010년에 국립수산과학원에서 실시한 황해 어장환경 모니터링 중 가로림만의 11개 정점에 대해 년 6회 짝수 달에 조사한 수온, 염분, 용존산소(DO), 화학적산소요구량(COD), 엽록소 $a$, 입자성부유물질(SPM) 및 영양염류를 분석하여 가로림만의 이화학적 특성을 파악하였다. 수온, 염분, COD, 용존성무기질소, 엽록소 $a$, SPM은 표 저층간의 유의한 차이가 있었으며, 그 외 조사 항목은 표 저층간의 차이가 없었다. 모든 조사 항목에서 정점간 유의적인 차이는 없었다. 수온은 전형적인 온대 수역의 변화 양상을 보였으며, 염분은 8월에 평균 31이상으로 저염분 현상은 발생하지 않았다. DO는 농도가 낮은 6~8월에 평균값이 빈산소 수괴 발생 농도인 3mg/L보다 높은 농도를 보였다. 엽록소 $a$는 전체적으로 6월 표층 $1.68{\mu}g/L$, 저층 $2.38{\mu}g/L$, 8월 표층 $1.68{\mu}g/L$, 저층 $1.57{\mu}g/L$로 여름철에 가장 높았다. 영양염류는 전체 조사시기별 중에서 2월이 높고 8월이 낮은 경향을 보였는데, 이는 여름철에 가로림만으로 들어오는 담수유입이 제한받고 여름철에 번식하는 식물플랑크톤에 의해서 영양염이 소비가 되었기 때문이라고 생각된다. DIN/DIP 비는 전체적으로 비슷한 값을 보였으며, 6월의 경우는 표층 30.52, 저층 37.89로 다른 조사시기별보다 높은 경향을 보였다. SPM은 2월 저층에서 44.15mg/L로 가장 높은 값을 보였는데, 이러한 현상은 겨울에 북서계절풍의 영향으로 사료된다. 영양염류의 결과와 저염분 현상 및 빈산소 수괴가 발생하지 않는 것으로 보아 가로림만은 외해의 해수 교환이 원활이 이루어지며, 작은 하천을 통해 들어오는 담수의 유입에 크게 영향을 받지 않는다. 그리고 해역별 수질등급은 전반적으로 I, II등급의 수질상태를 유지하고 있어 수산학적으로 매우 중요한 연안이므로 앞으로 지속적인 보전이 요구된다.

• 유기물자원화
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• 제15권1호
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• pp.178-184
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• 2007

분변토 처리의 기계화 및 자동화 공정 개발을 위하여, 본 연구에서는 슬러지 침출액을 이용한 지렁이 퇴비화 지표에 대하여 고찰하였다. 이 연구에서는 회분식 및 연속식 실험을 위하여 현장 하수 슬러지가 사용되었다. 슬러지 처리방버버에 따른, 발생되는 침출수의 이화학적 특성 변화는 거의 유사함을 나타내었다. 그러나, 산화환원전위, pH, 전기전도도, $NH_3-N$ 항목에서는 퇴비화 전후, 분명한 차이를 보였다. 또한, 지렁이 퇴비화 지표 설정에 가장 적합한 변수들은 ORP과EC임을 알 수 있었다. 이러한 연구 결과들은 실제적으로 분변토 처리가 이루어지는 지렁이 퇴비하 기술로 사용될 수 있을 것이다.

• Geomechanics and Engineering
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• 제15권5호
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• pp.1091-1100
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• 2018

In this study, the relationships between hydraulic conductivity of GCLs and physico-chemical properties of bentonites were assessed. In addition to four factory manufactured GCLs, six artificially prepared GCLs (AP-GCLs) were tested. AP-GCLs were prepared in the laboratory without bonding or stitching. A total of 20 hydraulic conductivity tests were conducted using flexible wall permeameters ten of which were permeated with distilled deionized water (DIW) and the rest were permeated with tap water (TW). The hydraulic conductivity of GCLs and AP-GCLs were between $5.2{\times}10^{-10}cm/s$ and $3.0{\times}10^{-9}cm/s$. The hydraulic conductivities of all GCLs to DIW were very similar to that of GCLs to TW. Then, simple regression analyses were conducted between hydraulic conductivity and physicochemical properties of bentonite. The best correlation coefficient was achieved when hydraulic conductivity was related with clay content (R=0.85). Liquid limit and plasticity index were other independent variables that have good correlation coefficients with hydraulic conductivity (R~0.80). The correlation coefficient with swell index is less than other parameters, but still fairly good (R~0.70). In contrast, hydraulic conductivity had poor correlation coefficients with specific surface area (SSA), smectite content and cation exchange capacity (CEC) (i.e., R < 0.5). Furthermore, some post-test properties of bentonite such as final height and final water content were correlated with the hydraulic conductivity as well. The hydraulic conductivity of GCLs had fairly good correlation coefficients with either final height or final water content. However, those of AP-GCLs had poor correlations with these variables on account of fiber free characteristics.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.3112-3112
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• 2001

Near-Infrared Spectroscopy (NIRS) was investigated aiming at the identification of falsified drugs. The identification is based on comparison of the NIR spectrum of a sample with a typical spectra of an authentic drug using multivariate modelling and classification algorithms (PCA/SIMCA). Two spectrophotometers (Brimrose - Luminar 2000 and 2030), based on acoustic-optical filter (AOTF) technology, sharing the same controlling computer, software (Brimrose - Snap 2.03) and the data acquisition electronics, were employed. The Luminar 2000 scans the range 850 1800 nm and was employed for transmitance/absorbance measurements of liquids with a transflectance optical bundle probe with total optical path of 5 mm and a circular area of 0.5 $\textrm{cm}^2$. Model 2030 scans the rage 1100 2400 nm and was employed for reflectance measurement of solids drugs. 300 spectra, acquired in about 20 s, were averaged for each sample. Chemometric treatment of the spectral data, modelling and classification were performed by using the Unscrambler 7.5 software (CAMO Norway). This package provides the Principal Component Analysis (PCA) and SIMCA algorithms, used for modelling and classification, respectively. Initially, NIRS was evaluated for spectrum acquisition of various drugs, selected in order to accomplish the diversity of physico-chemical characteristics found among commercial products. Parameters which could affect the spectra of a given drug (especially if presented as solid tablets) were investigated and the results showed that the first derivative can minimize spectral changes associated with tablet geometry, physical differences in their faces and position in relation to the probe beam. The effect of ambient humidity and temperature were also investigated. The first factor needs to be controlled for model construction because the ambient humidity can cause spectral alterations that should cause the wrong classification of a real drug if the factor is not considered by the model.

• The Korean Journal of Ecology
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• 제19권6호
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• pp.529-541
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• 1996

During the period of December 1992 (winter-spring) and from February 1995 (winter-spring), the leaf processing rates of oak (Quercus serrata) and tulip (Liriodendron tulipifera) tree was investigated in the headwater streams in southeastern part of Korea in conjunction with the distribution pattern of macroinvertebrate fauna. Using two types of bags ($10\times30cm$ with 5 g of dry leaves; open bag with holes, closed bag without holes), decomposition rates of oak and tulip tree by shredder and/or microbiota at a reatively undisturbed 2nd-order stream were compared, Regardless of leaf type, leaves in the open bage decomposed slightly faster than those in the closed bags. In the 1992 experiment, osk leaves decomposed much slower than tulip leaves (after 138 degree days, osk : closed, 0.006% loss/day ; open, 0.008 ; tulip: closed, 0.021 ; open, 0.023; n=2). The of the first experiment using oak leaves in 1995 were similar to those of the first experiment (after 151 degree days, oak: closed, 0.005% loss / day; open, 0.006; n=6). Over 50% of invertebrates from 122 leaf pack samples collected from 12 streams during the winter period of 1994 were identified as shredders (shredder, 56.2; collector, 32.7; scraper, 8.65; predator, 2.45%). Among shredders, Gammarus sp. and Tipula sp. were dominant species in terms of number and biomass (8.2 ind./g, 1.0 ind./g AFDW of leaves). Among many physico-chemical parameters, the width of stream channel was found to be the most influential factor in the distribution of Gammarus and Tipula (Gammarus: r=-0.34, P<0.001;Tipula:r=0.40, P<0.001). Considering the fact that oak is one the dominant riparian vegetation in the southeastern part of korea, the patterns of oak processing and shredder distribution shown in theis study may well represent some of the important characteristics of headwater steams in southeastern Korea.

• 한국환경과학회지
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• 제9권2호
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• pp.115-123
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• 2000

The dynamics of water quality and phytoplankton population had examined by monthly sampling from the upper to the lower part of watergate in an artificial Shihwa Reservoir in which situated near newly cities and incustrial complex on the west coast of Korea from January 1997 to December 1998. Among environmental factors, yearly average concentration of chl-a, TN and TP seemed to eutrophic or hypertrophic conditions that ranged 146.4~245.8 $\mu\textrm{g}$/$\ell$, 1.6~2.7 mg N/$\ell$, 258~448 $\mu\textrm{g}$ P/$\ell$, 26.9~80.7 $\mu\textrm{g}$/$\ell$, 1.0~2.4 mgN/$\ell$ and 74~239 $\mu\textrm{g}$P/$\ell$ respectively. Water quality was extremely deteriorated to consistently accumulation into inner reservoir by load of pollutants from autochthonous and allochthonous until early July 1997 after embankment. Water pollution of Shihwa Reservoir was remarkble on the biological condition with largely persistent bloom of phytoplankton and increase rate of standing crops was 2.4/yr. The development trend of phytoplankton in water ecosystem were closely related to increse and decrease of physico-chemical factors and those scale seemed to control by nutrient contents. Inflow of seawater into reservoir to object of repair of water quality. As to see dominant species, composition of those composed to mostly freshwater algae before inflow of seawater such as Selenastrum capricornutum of green algae, cyclotella atomus, C. meneghiniana of diatom and Microcystis spp. of blue-green algae and the other hand brackish algae were dominated after inflow of seawater such as Chaetoceros dicipiens, Skeletonema costatum of diatom, Dinophysis acuminata, Gymnodinium mikimotoi, G. sanguineum, Gyrodinium spirale, Prorocentrum minmum of dinoflagellate and Eutreptiella gymnastica of euglenoid. Moreover, small flagellates including Chroomonas spp. of cryptomonad were abundant throughout the year. The cause of water deterioration during fill of the freshwater were complexly supported with extra and intra parameters. The variation pattern of phytoplankton were related to water temperature and salinity by inflow of seawater based to plentiful nutrients. The dynamics of phytoplankton were assessed to ecosystem that clearly condition of dominant by unique or a few angel species seasonally.

• 한국축산식품학회지
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• 제35권3호
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• pp.370-381
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• 2015

This study was designed to determine the usability of lemon fiber (LF-2%, 4%, 6%) and carrot fiber (CF-2%, 4%, 6%) to produce lowfat beef hamburgers. To that end, a certain amount of fat was replaced with each fiber. The proximate composition, pH value, cholesterol content, cooking characteristics, color, texture profile, and sensory properties of low-fat beef hamburgers were investigated. LF increased moisture content and cooking yield due to its better water binding properties, while CF caused higher fat and cholesterol contents owing to its higher fat absorption capacity (p<0.05). LF resulted in a lighter, redder, and more yellow color (p<0.05). Hardness, gumminess, springiness, and chewiness parameters decreased when the usage level of both fibers increased (p<0.05). However, more tender, gummy, springy, and smoother hamburgers were produced by the addition of CF in comparison with LF (p<0.05). Moreover, hamburgers including CF were rated with higher sensory scores (p<0.05). In conclusion, LF demonstrated better technological results in terms of cooking yield, shrinkage, moisture retention, and fat retention. However it is suggested that CF produces better low-fat hamburgers since up to 2% CF presented sensory and textural properties similar to those of regular hamburgers.

• 한국토양환경학회지
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• 제2권3호
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• pp.31-38
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• 1997

산성폐수에 함유된 오염물질의 물리적 화학적 특성이 배우 복잡하기 때문에 산성폐수에 의해 오염된 지표수나 지하수등의 오염정도를 지역적, 시간적 변화에 따라 비교하는 일은 쉽지가 않다. 본 논문에서는 산성폐수에 의해 오염된 지표수나 지하수의 오염도를 정량적으로 평가할 수 있는 수학적 지표를 제시하였으며, 오염지표를 이용하여 국내 폐탄광의 갱내 유출수에 대한 오염도를 검토하였다. 사용된 오염지표(Acid Mine Drainage Index)는 수질의 오염정도를 가장 잘 나타낼수 있는 7개의 변수 즉, pH값, 황산염(Sulfate), 철, 망간, 알루미늄, 구리 및 아연 함량을 이용하여 계산하였다. 사용된 변수는 오염도에 미치는 상대적인 중요도를 감안하여 가중치를 사용하였으며 , pH값 및 황산염함량에 가장 높은 가중치를 부여하였다. 국내 폐광산에서 유출되는 산성폐수의 오염도 평가결과 경북 문경에 소재한 석봉탄광이 조사탄광중 상대적으로 오염도가 높았으며, 지역적으로 영동지역에 위치한 폐탄광의 갱내 유출수가 영서, 중부, 서부 및 남부에 위치한 폐탄광에 비해 오염도가 높게 나타났다.

• Mycobiology
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• 제40권3호
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• pp.151-158
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• 2012

Very few studies have addressed the phylogenetic diversity of fungi from Northeast India under the Eastern Himalayan range. In the present study, an attempt has been made to study the phylogenetic diversity of culturable soil fungi along the altitudinal gradients of eastern Himalayas. Soil samples from 24 m above sea level to 2,000 m above sea level altitudes of North-East India were collected to investigate soil micro-fungal community structure and diversity. Molecular characterization of the isolates was done by PCR amplification of 18S rDNA using universal primers. Phylogenetic analysis using BLAST revealed variation in the distribution and richness of different fungal biodiversity over a wide range of altitudes. A total of 107 isolates were characterized belonging to the phyla Ascomycota and Zygomycota, corresponding to seven orders (Eurotiales, Hypocreales, Calosphaeriales, Capnodiales, Pleosporales, Mucorales, and Mortierellales) and Incertae sedis. The characterized isolates were analysed for richness, evenness and diversity indices. Fungal diversity had significant correlation with soil physico-chemical parameters and the altitude. Eurotiales and Hypocreales were most diverse and abundant group of fungi along the entire altitudinal stretch. Species of Penicillium (D=1.44) and Aspergillus (D=1.288) were found to have highest diversity index followed by Talaromyces (D=1.26) and Fusarium (D=1.26). Fungal distribution showed negative correlation with altitude and soil moisture content. Soil temperature, pH, humidity and ambient temperature showed positive correlation with fungal distribution.

• 한국식품영양학회지
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• 제29권5호
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• pp.677-683
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• 2016

To enhance the physiological activities and reduce the off-flavor of garlic in kimchi, we manufactured kimchi seasoning replaced with 25~75% black garlic, we evaluated microbiological, physico-chemical and sensory evaluation. The changes of total aerobic and lactic acid bacteria were similar between the control and the kimchi seasoning replaced with black garlic during storage periods. The lightness of the kimchi seasoning replaced with black garlic was lower than that of the control and decrease of lightness was proportional to the concentration of black garlic. The redness and yellowness of the kimchi seasoning replaced with black garlic were decreased to the concentration of added black garlic and changes of the redness in all the samples were slightly increased during storage periods. But the yellowness did not change during storage periods. The changes of pH and acidity did not differ between the control and the samples of replaced with black garlic during storage periods. The sensory parameters including taste and flavor did not differ among treatments during storage periods. But color and overall acceptance of the control and sample replaced with 25% black garlic were higher than those of the samples replaced with 50 and 75% black garlic.