• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.3
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• pp.1-5
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• 1985

CulnSe2 single crystals were grown by the Bridgman method. The n.CulnSe2 single cry seals with a carrier concentration of 2.6$\times$1016/㎤ were obtained by a thermal treatment of the grown CulnSe2 single crystals in selenium atmosphere. The solar cell of n.CulnSe2-3M KOH+3M Na2 S+4M S junction was prepared by using n.Culnsel single crystal as a photoanode, 3M KOH+SM Nat S+4M S as Polysulfide solutions. The FF of the solar cell was 0.44 under 100 mW/cml illumination condition, and the conversion efficiency was 5.67%.

• Journal of the Korean Chemical Society
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• v.50 no.4
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• pp.321-327
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• 2006

red 1 and acid blue 92, anionic dyes, were removed from synthetic wastewater by the surfactant-modified clay minerals. Two different clays, such as Korean clay(M78) and Japanese clay(KJ) were treated with three different sulfactants, CTMA, DSDMA and TMSA. The surfactant-modified clay minerals such as M-1(CTMA), M-3(TMSA), KJ-1(CTMA) and KJ-3(TMSA), showed high removal efficiencies with dyes, while M-2(DSDMA) and KJ-2(DSDMA) could adsorb both dyes with relatively low efficiencies. Furthermore, almost 100% absorption of both dyes onto M-1(CTMA) and KJ-3(TMSA) revealed the possibility that these materials can be used for the removal of hazardous organic dyes from wastewater.

• Journal of Embryo Transfer
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• v.9 no.3
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• pp.235-241
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• 1994

The study was conducted to determine the optimal hormone and glucose levels during the in vitro culture of bovine oocytes matured and fertilized in vitro for blastocyst development. Oocytes matured in TCM 199 + 10% FCS + hormones and glucose were fertilized in vitro in a TALP medium with swim up separated and heparin-treated epididymal cauda spermatozoa. Oocytes were cultured for 2~5 days in synthetic oviduct fluid medium (SOFM) supplemented with 10% FGS and with different hormone and glucose levels, and further cultured 5 days same medium in SOFM. The results are summarized as follows : The in vitro maturation and penetration rates of porcine oocytes cultured in TCM 199 media containing PMSG, hCG, PMSG + hCG, hCG + $\beta$ estradiol, PMSG + $\beta$ estradiol 0 to20 hours after insemination were 88.0% and 81.8%, 82.6% and 68.4%, 80.0% and 75.0%, 80.0% and 65.0%, 77.3% and 64.7%, respectively. The in vitro maturation and penetration rates of porcine oocytes cultured in TCM 199 media containing PMSG, hCG, PMSG + hCG, hCG + $\beta$ estradiol, PMSG + $\beta$ estradiol 20 to 40 hours after insemination were 92.0% and 87.0%, 92.0% and 82.6%, 91.3% and 81.0%, 85.2% and 73.9%, 87.5% and 81.0%, respectively. The cleavage and in vitro developmental rates to blastocyst of porcine oocytes cultured in TCM 199 media containing 0.05 mM, 0.10 mM, 0.30 mM, 0.50 mM, 1.00 mM, and 3.00 mM glucose lelvels 0~3 days after insemination were 31.5~48.1% and 10.0~16.7%, respectively. The cleavage and in vitro developmental rates to blastocyst of porcine oocytes cultured in TCM 199 media containing 0.05 mM, 0.10 mM, 0.30 mM, 0.50 mM, 1.00 mM, and 3.00 mM glucose levels 4~8 days after insemination were 30.0~53.8% and 8.7~19.2%, respectively. The cleavage and in vitro developmental rates to blastocyst were higher in TCM 199 media containing various glucose levels 0~3 days after insemination than 4~8 days.

• The korean journal of orthodontics
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• v.29 no.3 s.74
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• pp.383-397
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• 1999

Bone is a dynamic tissue which is constantly remodelled by subsequent cycles of bone resorption and formation. Glucocorticoid and vitamine $D_3$ are known as regulating substances in bone metabolism. In vitro experiments using bone tissue, it was suggested that glucocorticoid inhibits bone resorption, whereas the effect of glucocorticoid on bone formation are complex- increasing or decreasing effect. The active form of vitamin $D_3$, 1,25-dihydroxycholecalciferol[1.25-$(OH)_2D_3$], has been reported to stimulate osteoblastic activities including the production of ALP, type I collagen, and osteoclacin. The purpose of this study was to evaluate the effect of admixture of vitamin $D_3$ and dexamethasone, one of glucocorticoids, on osteoblastic cell line(MC3T3-E1). Alkaline phosphatase(ALP) and MTT assay were conducted in the cultivated cells with 1, 10, 100nM/ml of 1,25-$(OH)_2D_3$ and/or 10nM/ml, 100nM/ml, $1{\mu}M/ml$ of dexamethasone. The observed results were as follows. 1. The activity of osteoblastic cells with $1{\mu}M/ml$ of dexamethasone was significantly increased at 1-day cultivation with comparison to control group, but was decreased afterwards. But the activity of ALP was greatest in $1{\mu}M/ml$ of dexamethasone and increased with time lapsed. 2. The activity of osteoblastic cells with vitamin $D_3$ was significantly increased dose-dependently at 1-day cultivation, but was significantly decreased in l00nM/.ml at 2-day cultivation, and was a little increased again at 3-day cultivation. The activity of ALP was increased in 10nM/ml or 100nM/ml at 2-day or 3-day cultivation, and was greatest in 100nM/ml at 3-day cultivation. 3. In case of admixture of dexamethasone and vitamin $D_3$, the cellular activity was decreased in any concentration of vitamin $D_3$ at 2-day cultivation, but was increased again at 3-day cultivation, which was greater than that in control or dexamethasone only group. The activity of ALP was decreased at 1-day cultivation, but was increased in the admixture of 10nM/ml or 100nM/ml of dexamethasone with 100nM/ml of vitamin $D_3$ at 2-day cultivation, and was again decreased at 3-day cultivation.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.1945-1954
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• 2000

This study provides economical installation capacities for wastewater reclamation and reusing system in 7 areas of South Korea applying to contact aeration process using NPV(net present value) model based on cost-benefit. First. considering only private benefits. economical installation capacities for wastewater reclamation and reusing system applying to contact aeration process in household use were more than $500m^3/day$ in Pusan. $1,000m^3/day$ in Taegu. $2,000m^3/day$ in Kwangju. However. installation capacities in Seoul. Inchen, Taejon, and Ulsan were not optimal for $3,000m^3/day$. Therefore, supply ways of wastewater reclamation and reusing system in household use in the latter areas were more optimal local recirculation system than individual recirculation system. Economical installation capacities for wastewater reclamation and reusing system in business use were more than $100m^3/day$ in Seoul. Pusan. and Kwangju and which were $300m^3/day$ in Taegu, Inchen, Taejon, and Ulsan. Economical installation capacities for wastewater reclamation and reusing system in commercial use were more than $100m^3/day$ in Seoul, Pusan, Taegu, Kwangju, Taejon, and Ulsan, and which were $300m^3/day$ in Inchen. Second, considering only social benefits. economical installation capacity for wastewater reclamation and reusing system applying to contact aeration process was more than $100m^3/day$.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.5
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• pp.742-747
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• 2019

Objective: A concentration of airborne bacteria generated from swine houses is recognized to be relatively higher than other work places and it is essential to optimally manage it to prevent farmers' respiratory diseases. This study was conducted to assess the distribution characteristics of airborne bacteria in swine houses located at South Korea. Methods: A total 27 pig buildings of the enclosed type operated with mechanical ventilation system by a side wall fan and deep-pit manure system with slats were surveyed. Air samples were collected at 1.0 m above the middle floor in pig housing room. A six-stage viable particulate cascade impactor was used to identify the distribution of the sizes of particles in diameter. Results: Seasonal mean levels of airborne bacteria in the housing rooms of gestation/farrowing pigs, nursery pigs and growing/fattening pigs were 3,428(${\pm}1,244$) colony forming unit $(cfu)/m^3$, $8,325({\pm}3,209)cfu/m$, and $13,254({\pm}6,108)cfu/m^3$ for spring; $9,824({\pm}2,157)cfu/m^3$, $18,254({\pm}5,166)cfu/m^3$, and $24,088({\pm}9,274)cfu/m^3$ for summer; $1,707({\pm}957)cfu/m^3$, $4,258({\pm}1,438)cfu/m^3$, and $8,254({\pm}2,416)cfu/m^3$ for autumn; and $2,322({\pm}1,352)cfu/m^3$, $6,124({\pm}1,527)cfu/m^3$ and $12,470({\pm}4,869)cfu/m^3$ for winter, respectively. Conclusion: Concentrations of airborne bacteria according to pig housing type were highest in growing/fattening housing room followed by nursery housing room and gestation/farrowing housing room. In terms of seasonal aspect, the pig building showed the highest levels of airborne bacteria in summer followed by spring, winter and autumn. The respirable airborne bacteria which are ranged between 0.6 and $4.7{\mu}m$ accounted for approximately 60% compared to total airborne bacteria regardless of pig housing type.

• Journal of Environmental Health Sciences
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• v.18 no.1
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• pp.6-11
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• 1992

This study was carried out to investigate exposure level, size distribution, and respirable mass fraction of airborne coal dust and heavy metal concentration of respirable coal dust at each work site in coal briquet factory from July 1991 to September 1991. Geometric mean of total dust concentration was 10.88mg/m$^{3}$ at storage shop, 8.22mg/m$^{3}$ at pulverize shop, and 3.79mg/m$^{3}$ at rotary press shop, respectively, but those at storage and pulverize shop were higher than TLV. Geometric mean of respirable coal dust concentration wat 1.03mg/m$^{3}$ at storage shop, 0.78mg/m$^{3}$ at pulverize shop, and 0.55mg/m$^{3}$ at rotary press shop, respectively, which were lower than TLV Aerodynamic 50% cutoff diameter of the suspended coal dust was 5$\mu$m at rotary press shop and 6.8$\mu$m at storage shop, ranged to thoracic particulate defined by ACGIH, and deposited in the region of repiratory system. The mass fraction rate of respirable dust to the total coal dust was 26.2% at rotary press shop, 18.8% at storage shop, and 13.8% at pulverize shop, respectively. Heavy metal concentrations of the respirable coal dust were 0.028mg/m$^{3}$ ib Fe, 0.0081mg/m$^{3}$ in Cu, and 0.0039mg/m$^{3}$ in Pb.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.196-200
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• 1993

A full understanding of the interdependence of leaf nitrate (($No_3$￣) metabolism and symbiotic nitrogen($N_2$) fixation in legume crops is needed to help maximize the use of both N sources as well as to improve forage quality through the inhibition of leaf nitrate accumulation. The present work examines the effects of added nitrate, the level of which are 0,2,4,8 and 12mM, on the nodule formation and leaf nitrate utilization and on the possibility of inducing nitrate-toxicity to livestocks in two alfalfa varieties, ' Vernal ' of grazing type and ' Victoria ' of hay type. Higher level of exogeneous nitrate resulted in the increased above-ground dry weight. Nodulation was inhibited severely when more than 8mM NO$_3$￣ was supplied to alfalfa plants, and leaf nitrate reductase reached a maximunm at 4mM nitrate supply. The $V_{max}$of nitrate reductase in leaves of Vernal was similar to that of Victoria, whereas the $K_m$ of Vernal was higher than that of Victoria. High accumulation of leaf nitrate, $4{\times}10^{-5}$ g/g leaf fresh weight, was shown at 12mM nitrate supply, which was thought to be not enough to induce nitrate-toxicity to livestocks.icity to livestocks.

• Analytical Science and Technology
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• v.17 no.5
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• pp.401-409
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• 2004

The 7-keto-DHEA-acetate is converted to 7-keto-DHEA, a metabolite of DHEA, and similar to its metabolism. We studied the metabolite M3, M4, and M5 of 7-keto-DHEA-acetate. The estimated molecular weight of M3 and M4 was 304 which were supposed to have more 3 hydroxyl and/or ketone groups. We could know that M3 is the 7-OH-DHEA which has the hydroxyl groups on 3 and 7-carbon and a ketone group on 17-carbon. In case of M4, it is the 7-oxo-diol metabolite which has the hydroxyl groups on 3 and 17-carbon and a ketone group on 7-carbon. The M5 was supposed that the molecular weight is 320 and has the three hydroxyl groups on 3, 6, and 16 carbon and the ketone group on 17-carbon. After dosing, 7-OH-DHEA showed the maximum urine flow in human urine after 5 hr and decreased rapidly. But we could find it until 58 hr why is a higher remaining substance.

• KCID journal
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• v.18 no.1
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• pp.68-80
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• 2011

To provide a operation rule curve for reservoir with low ratio of watershed area to paddy field area, Duckyong reservoir with watershed area of $15.8km^2$ and paddy field area of 1,071ha was selected, in which 4 meters are being heightened and full water levels will be increased from EL.26.0m to EL.30.0m, total water storages from 365.6M $m^3$ to 708.0M $m^3$. There was no operation rule curve that satisfied over 90% reliability of water supply in reservoir with watershed area of 1.48 times of paddy field area. The differences between observed and simulated reservoir daily water storages were minimized to determine parameters for simulating reservoir inflow in case of paddy field area of 550ha from 1991 to 2010. A operation rule curve was drawn to have a maximum storage with total water storage, which was in paddy field area of 700ha with ratio of 2.3 between watershed area and paddy field area. This case showed that annual irrigation water supply was 668M $m^3$ and instream flow of 57M $m^3$, water supply reliability of 55.6% in normal operation, and annual irrigation water supply was 605M $m^3$ and instream flow of 38M $m^3$, water supply reliability of 95.6% in withdrawal limited operation. Water supply reliabilities showed 35.6% without flood regulation and 17.8% with flood regulation in existing reservoir before heightening.