• The Korean Journal of Ecology
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• v.24 no.5
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• pp.289-296
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• 2001

Community structure of the Salix and physico-chemical properties of sediment were studied from July to September, 2000 in Nam-River watershed for the purpose of inquiring niche breadth, niche overlap and the environmental factors affecting the distribution of Salix species. Among eleven Salix species, the dominant species was Salix koreensis, while the rests were such order as S. nipponica, S. gracilistyla and S. glandulosa by the relative abundance based on the basal area. Mean values and the ranges of sediment properties such as pH, conductivity, water content, organic matter, total nitrogen, available phosphorus, clay, silt and sand were 5.3∼6.3, 14∼351 μmho/cm, 0.1∼3.4%, 0.5∼7.3%, 0.01∼0.2%, 0.1∼0.4 mg/100 g, 1.7∼22.0%, 0.2∼40.8%, 39.7∼98.0%, respectively. Altitude and annual mean temperature of each site were 20∼620 m and 9.3∼13.0℃, respectively. Niche breadth was estimated by considering the differences of the soil texture as the differences of state of source. S. glandulosa was the broadest at the level of 0.77, while the rests were such order as S. koreensis, S. nipponica were 0.69, 0.54, respectively. The niche overlap showing the level of interspecific competition was the largest as 0.94 between S. purpurea var. japonica and S. purpurea var multinervis, while S. graciliglans and S. purpurea var. japonica 0.92, S. graciliglans and S. purpurea var. multinervis 0.87, respectively. According to the analysis of the correlation between eleven species of Salix and eleven environmental factors, S. gracilistyla showed the negative correlation with conductivity, water content, total nitrogen, clay, silt and annual mean temperature, and showed the positive correlation with total nitrogen, sand and altitude. S. graciliglans showed the negative correlation with conductivity, water content, organic matter, clay, silt and annual mean temperature, and showed the positive correlation with total nitrogen, sand and altitude. S. nipponica showed the negative correlation with sand and altitude, and showed the positive correlation with water content, total nitrogen, clay, silt and annual mean temperature. S. nipponica showed the opposite results of S. gracilistyla. Soil texture, total nitrogen, water content, altitude and annual mean temperature were affecting the distribution of Salix species in Nam-River watershed.

• Journal of Animal Science and Technology
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• v.49 no.6
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• pp.871-880
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• 2007

This study was conducted to investigate the relationship between the socio-demographic factors and the Korean consumers’ palatability evaluation and to collect the sensory information for development of prediction palatability model of Hanwoo beef. Ten cuts〔Abjin (short plate), Bosup (top sirloin), Cheggt (striploin), Dngsim (loin), Guri (chuck tender), Hongduke (eye of round), Moksim (chuck roll), Sulgit (bottom round), Udoon (top round), Yangi (brisket)〕 were separated from 10 Hanwoo bulls beef(～24 months old) and prepared with the same manner for 3 different cooking methods such as boiling, grilling and roasting. The cooked beef samples were served to 650 consumers recruited from Seoul, Joongbu, Honam and Youngnam locations and evaluated tenderness, juiciness, flavor and overall acceptability. The living location, age, gender, occupation, eating habit and cut were significantly related with the sensory properties when bull beef were cooked as boiled cooking(p<0.05). In grill cooking, only occupation, income and cut had the significant effect on the overall acceptability of Hanwoo bull beef(p<0.01). When bull beef were cooked as Korean traditional roast cooking, consumer’s sensory properties were significantly different by the living location, age, occupation, income, eating habit of consumers and cut(p<0.05). Also, results from the principal component analysis showed that palatability scores of Korean consumers were decided with different contribution scores of tenderness, juiciness, flavor and overall acceptability of cut depending on cooking methods. In conclusion, Korean consumers’ palatability for Hanwoo bull beef were related with the socio-demographic factors and the sensory results were different by cut and cooking methods.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.216-224
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• 2005

Chromatography has now been used successfully to provide the requisite purity for human plasma-derived biop-harmaceuticals such as coagulation factors and immunoglobulins. Recently, increasing attention has been focused on establishing efficient cleaning procedures to prevent potential contamination by microorganisms as well as carry-over contamination from batch to batch. The purpose of present study was to develop a cleaning validation system for the assurance of virus removal and/or inactivation during chromatography process. In order to establish an assay system for the validation of virus clearance during chromatography cleaning process, a quantitative real-time PCR method for porcine parvovirus(PPV) was developed, since PPV, a model virus for human parvovirus B19, has a high resistance to a range of physico-chemical treatment. Specific primers for amplification of PPV DNA was selected, and PPV DNA was quantified by use of SYBR Green I. The sensitivity of the assay was calculated to be 1.5 $TCID_{50}/ml$. The established real-time PCR assay was successfully applied to the validation of PPV removal and cleaning during SP-Sepharose cation chromatography for thrombin purification and Q-Sepharose anion chromatography for factor VIII purification. The comparative results obtained by real-time PCR assay and infectivity titrations suggested that the real-time PCR assay could be a useful method for chromatography cleaning validation and that it could have an additive effect on the interpretation and evaluation of virus clearance during the virus removal process.

• Journal of the Mineralogical Society of Korea
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• v.16 no.1
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• pp.33-47
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• 2003

Various applied-mineralogical characterization including measurements of surface area, size distribution, swelling index, and viscosity were done for some domestic bentonites in order to decipher the rheological properties and their controlling factors. The bentonites, which are Ca-type and relatively low-grade (rnontmorillonite contents: 30 ∼ 75 wt%), occur mostly as subhedral lamellas with the size range of 2 ∼ 4 $\mu\textrm{m}$. The size distribution of mineral fractions in bentonite suspension is dominant in the range of 10 ∼ 100 $\mu\textrm{m}$, and though rather complicated, exhibits roughly bimodal patterns. The feature is more conspicuous in the case of zeolitic bentonite. The bentonites have surface areas ranging 269 ∼ 735 $\m^2$/g, which are measured by EGME adsorption method. The EGME surface areas are nearly proportional to the rnontmorillonite contents, moisture contents, or total CEC. In the surface area measurements, zeolitic bentonites have slightly higher values than those zeolite- free types. The measured swelling index and viscosity of domestic bentonites are comparatively low in values. The swelling values of bentonites were measured to be 250∼500% at maximum by progressively mixing amounts of 2 ∼ 5 wt% Na$_2$CO$_3$, which varies depending on the contents of rnontmorillonite and other impurities, especially zeolite. Much amount of sodium carbonate is required for optimum swelling property of zeolitic bentonited which has usually strong Na- exchanged capacity. The bentonites, which are comparatively feldspar-rich and low in size and crystallinity, tend to be higher in viscosity values. Tn addition, the viscosity is largely higher in case of the bentonites with higher pH in suspension. However, the rheological properties of bentonites such as swelling index and viscosity do not show any obvious relationships with rnontmorillonite contents and mean particle size in suspension. In contrast, roughly speaking, the swelling index of bentonites is reversely proportional to the values of surface area which can be regarded as a collective physico-chemical parameter encompassing all the effects caused by mineral composition, surface charge, particle size, morphological farm, and etc. in bentonites. Thus, the rheological properties in bentonite suspension appear to be rather complicated characteristics which mainly depend on the flocculation of clay particles and the mode of particle association, i.e. quasicrystals, controlled by surface charge, morphology, size, and texture of rnon-tmorillonite, and which partly affected by the finer impurities such as zeolite.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.275-280
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• 2015

The objective of this study was to investigate the effect of drip irrigation level on soil salinity and growth of broccoli (Brassica oleracea L. var. italica) at the 'Saemangeum Reclaimed Tidal Land' from April to June, 2015. Drip irrigation was conducted at 1.5, 3.0 and $6.0mm{\cdot}day^{-1}$ level for reduction of resalinization in the plastic vinyl house using 10cm spacing drip irrigation tape. At harvesting stage, the average EC of surface soil was $10.9dS{\cdot}m^{-1}$ for $1.5mm{\cdot}day^{-1}$, $11.5dS{\cdot}m^{-1}$ for $3.0mm{\cdot}day^{-1}$ and $5.1dS{\cdot}m^{-1}$ for $6.0mm{\cdot}day^{-1}$ and was significantly reduced by 52~56% in $6.0mm{\cdot}day^{-1}$ treated plot compared to those in 1.5 and $3.0mm{\cdot}day^{-1}$ plots. The fresh bud weights of 1.5, 3.0 and $6.0mm{\cdot}day^{-1}$ treatment plots were 60.9, 129.1 and $371.3g{\cdot}plant^{-1}$, respectively. The estimated soil EC for 50% yield reduction was $7.6dS{\cdot}m^{-1}$ and the desalinization depth by drip irrigation was 30~40cm in soil profile. The total amount of drip irrigation water was estimated to be 422mm and the daily drip irrigation level was $6.0mm{\cdot}day^{-1}$ for the prevention of resalinization during the broccoli growing period at the 'Saemangeum Reclaimed Tidal Land'. Our results suggested that drip irrigation shows effectiveness on the lowering the soil salinity according to the drip irrigation quantity but it needs more research on this study because dynamics of salts in soil can vary with many factors such as soil physico-chemical properties and seasonal climate.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.1
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• pp.26-37
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• 1992

Fifty-five field experiments were conducted in order to find out some useful indices for the prediction of N-supplying capability(NSC) of soils under cultivation of corn in Pennsylvania over 3 years from 1986. Contents of $NO_3-N$, absorbance at 200 nm of the extract from soil with 0.01M $NaHCO_3$ were identified to be used as indices before planting. Methods for the estimation of organic nitrogen available later in the growing season(KCLA-N, PBBA-N, UV260 nm absorbance of $NaHCO_3$ extract) were not to be used as good indices individually, but when those are combined together with inorganic $NO_3-N$ showed a highly significant correlationship with the NSC. The year of an even distribution of rainfall, 1987, gave the highest significant correlationship between NSC and the indices. For soils of the same texture with slightly different physical properties, combined indices obtained from physico-chemical factors improved the degree of predictability when the grades of soil slope, depth of Ap were considered at the same time. More futher researches such as this need to be done before any conclusive result can be drawn.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.239-251
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• 2011

To compare the different water environments in the Jigsaw stream (st. 1, 2) and Jujin stream (st. 3, 4) crossing over the Byeonsan-Bando and Seonunsan parklands, the physico-chemical factors and the species compositions of epilithic diatoms were analyzed from March 2009 to February 2010. The mean values of conductivity (681.1 ${\mu}S\;cm^{-1}$), suspended solids (27.83 mg $L^{-1}$), biological oxygen demand (3.15 mg $L^{-1}$), total nitrogen (3.24 mg $L^{-1}$), total phosphorus (0.24 mg $L^{-1}$) and chlorophyll-${\alpha}$ (12.99 mg $m^{-3}$ ) in Jujin stream were significantly higher than each element in Jigsaw stream. Eighty taxa were classified into 73 species and seven varieties belonging to 24 genera, eight families, three suborders and two orders in Jigsaw stream. Eighty eight taxa were classified into 81 species and seven varieties belonging to 22 genera, seven families, three suborders and two orders in Jujin stream. Biological water quality assessments revealed that Jigsaw stream was ${\beta}$~${\alpha}$-oligosaprobic and Jujin stream was ${\beta}$-mesosaprobic. Dominant and diversity indices were indicated from 0.25~0.81 and from 1.73~4.14 in Jigsaw stream, respectively, and from 0.29~0.64 and from 2.72~4.02 in Jujin stream, respectively. Jujin stream was more eutrophic than those of Jigsaw stream. The different water environments between the two streams could be due to the different ecosystems of the neighboring basins of each stream crossing over in the mountain. Further studies should investigate the water environments of two streams by continuous and regular monitoring to analyze the different ecosystem mechanisms.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.181-187
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• 2004

Preparations of mesoporous materials using various templates and their applicability have been intensively investigated for many years. We studied on synthesizing mesoporous Ti02 with pores in which sensitive compounds having weak physico-chemical properties such as thermal or UV irradiation and low solubility in solvent are trapped. Prior to trapping OMC in the pores of mesoporous titania, OMC was nano-emulsified in O/W system using Lecithin. Thereafter the OMC was trapped in the pores of mesoporous titania using sol-gel method. Main focus of this work is to prepare OMC-trapped mesoporous titania and to trace the stability and solubility of nano-emulsified OMC in the pores of mesoporous titania, and compared with that of mesoporous silica. OMC-trapped mesoporous Inorganic-Organic hybrid titania showed higher factors in sun protecting and a skin penetration phenomenon was reduced.

• Economic and Environmental Geology
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• v.51 no.6
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• pp.473-483
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• 2018

Green-blue coloured supergene minerals are covering host rocks along the gallery wall in the Gukjeon mine, a lead - zinc skarn deposit located in Miryang, Gyeongsangnam-do. These minerals have been described as azurite or malachite, but recent study recognized that the green minerals are devilline and blue minerals are Cu-Zn hydrated sulfates, but exact identification and detailed mineral characteristics are also not well known. In this study, we divide green-blue minerals into five groups (GJG) according to their external features and conducted XRD and SEM analyzes in order to identify mineral name and clarify the mineralogical characteristics. GJG-1, a bright bluish green group, consists of brochantite and quartz and GJG-2, a pale green colour with easily crumbly, of schulenbergite and a small amount of gypsum. Although pale blue GJG-3 and glassy lustrous bluish green GJG-4 have the same mineral assemblages with serpierite and gypsum in spite of different colour and luster, gypsum content may control the physical properties. GJG-5 with a gel phase mixture of pale blue and dark blue mineral is comprised of hydrowoodwardite, glaucocerinite, bechererite, serpierite and gypsum. The six green-blue minerals from the Gukjeon mine could be classified by Cu:Zn ratio, (Si + Al) content, Si:Al ratio, and Ca content. The physico-chemical environment of mineral formation is considered to be controlled by the geochemical factors in the surrounding fluid, and it looks forward that the accurate formation environment will be revealed through additional research. This paper gives greater mineralogical significance in the first report of several hydrated sulfate such as serpierite, glaucocerinite and bechererite in Korea. It has also rarely been reported the occurrence of several Cu-Zn hydrated sulfate in the same deposit in the world.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.147-158
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• 2007

To clarify the bloom pattern and species succession in phytoplankton community, the population dynamics with the determination of physico-chemical factors have been studies in Masan Bay, the south sea of Korea, for the periods November 2003-October 2004. Concentration of $NH_4-N$ was always higher than that of $NO_3-N$, which was similar level as compared to other costal areas. $PO_4-P$ concentration was lower than those in other coastal areas but similar to oligotrophic environments. Thus, phosphate seems the limiting nutrient rather than nitrogen. $SiO_2-Si$ concentration was also low as compared to other costal areas. Si:P ratio was low from autumn to winter, suggesting silicate and/or phosphate limitation during this period. The cell density of phytoplankton was high in winter 2003 and early autumn 2004. The carbon biomass was high in winter 2003 and summer 2004. And chlorophyll-a concentration was high in late autumn 2003 and summer 2004. Among 78 species of phytoplankton found in the bay during the investigated period, dominant species were two diatoms of Cylindrotheca closterium, Skeletonema costatum, and three dinoflagellates of Heterocapsa triquetra, Prorocentrum minimum, P. triestinum, and one raphidophyte of Heterosigma akashiwo. P. minimum dominated from late autumn to winter, but it was replaced by H. triquetra in late winter. P. triestinum dominated from late spring to early summer. Simultaneously, H. akashiwo cell density steadily increased, and it became dominant with C. closterium in late summer. With decreasing of H. akashiwo and C. closterium, S. costatum became the most dominant species in autumn. The canonical analyses showed that total phytoplankton cell density related to diatom cell density and it was affected by temperature, and concentrations of $NO_3-N\;and\;PO_4-P$. The carbon bio-mass and $chlorophyll-{\alpha}$ concentration related to diatom- and dinoflagellate cell densities and these were affected by flagellate cell density, salinity, and concentrations of $SiO_2-Si\;and\;PO_4-P$. Last six years monitoring data in Masan city obtained from Korean Meteorological Agency indicates gradual increase in air temperature. And the precipitation decreased especially in spring season. The winter bloom found in 2003 may be caused by the increase in the temperature and this bloom subsequently induced the nutrients depletion, which continued until next spring probably due to no precipitation. Therefore, the spring bloom, which had been usually observed in the bay, might disappear in 2004.