• Journal of fish pathology
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• v.21 no.1
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• pp.13-20
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• 2008

This study evaluates the pathogenicity in striped beakperch, Oplegnathus fasciatus infected with red sea bream iridovirus (RSIV) at different water temperature (17°C, 20°C, 25°C and 27°C). When the fish group was infected with RSIV at 17°C and 20°C, cumulative mortality did not show any significant difference with control group. In contrast, the case at 25°C and 27°C, cumulative mortality reached more than 80%. However, RSIV was detected from all of the fish in each temperature. To confirm a relationship between temperature change and heat shock protein (HSP), partial HSP70 cDNA was isolated from striped beakperch.

• Journal of Aquaculture
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• v.12 no.1
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• pp.25-30
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• 1999

This study was carried out to produce the seedling of the larvae and juveniles of pale chup, Zacco platypus (Cyprinidae) in terms of artificial hatching, feeding behavior and growth rates. The total lengths of the newly hatched larvae were 7.6~8.2mm (mean: 7.97mm). The hatched larvae rose to the surface 3 days after hatching. The larvae were fed Daphnia, rotifer, Artemia and powdered feed. Hatching experiments were conducted in jar incubators under the different water temperature conditions, $20~32^{\circ}C$. The highest hatching rate was at $26^{\circ}C$ after 47 hours. Jar incubators was the highest hatching rate (89%), and cage and Californian incubators were useful and relatively high hatching rates (>89%). The size of the larvae 50 days after hatching were 30.0mm (25.6~32.0mm). As the water temperatures was increased, the growth rate of the larvae was also increased. Especially, the growth rates were favorable over $26^{\circ}C$, but survival was the worst at $32^{\circ}C$. This species was quick to accept assorted feed after hatching. The assorted feeds for flounder and rockfish better than that of carp in reference to growth rate.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.972-978
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• 2005

The present study was carried out to investigate the blood markers of Jeju horses. The redcell cypes (blood groups) and blood protein types (biochemical polymorphisms) were tested from 102 Jeju horses by serological and electrophoretc procedure, and their phenotypes and gene frequencies were estimated. The blood group and biochemical polymorphism phenotypes observed with high frequency were $A^{af}\;(27.45\%$), $C^{a}\;(99.02\%$), $K^{-}\;(97.06\%$), $U^{a}\;(62.75\%$), $P^{b}\;(36.27\%$), $Q^{c}\;(47.06\%$), $D^{cgm/dghm}\;(13.73\%$), $D^{adn/cgm}\;(9.80\%$), $D^{ad/cgm}$\;(8.82\%$), $D^{dghm/dghm}(7.84\%$), $D^{cgm/cgm}(7.84\%$), $AL^{B}\;(48.04\%$), $GC^{F}\;(99.02\%$), $AlB^{K}\;(97.06\%$), $ES^{FI}\;(36.27\%$), $TF^{F2}\;(25.49\%$), $HB^{B1}\;(45.10\%$), and $PGD^{F}\;(86.27\%$) in Jeju horses, respectively. Alleles observed with high gene frequency were $A^{af}$ (0.3726), $A^{C}$ (0.2647), $C^{-}$ (0.5050), $K^{-}$ (0.9853), $U^{-}$ (0.6863), $P^{b}$ (0.4657), $Q^{c}$ (0.5294), $D^{cgm}$ (0.3039), $HB^{B1}$(0.6863), $PGD^{F}$ (0.9265), $AL^{B}$ (0.6912), $ALB^{K}$ (0.9852), $GC^{F}$ (0.9950), $ES^{I}$ (0.5000) and $TF^{F2}$ (0.4950) in Jeju horses, and sfecific alleles, $D^{cgm(f)}$ (0.0196), $HB^{A}$ (0.0147), $HB^{A2}$ (0.0196), $ES^{G}$ (0.0441), $ES^{H}$ (0.0098), $TF^{E}$TF'(0.0246), $TF^{H2}$ (0.0049) and $PGD^{D}$ (0.0098) were detected in Jeju horses. These preliminary results present basic information for detecting the genetic markers in Jeju horse. and developing a system for parentage verification and individuals identification in jeju horses.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.6
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• pp.257-261
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• 2004

The pottery stones from the Taebek area consist of abundant quartz with kaolinite. In this study, the characteristics of pottery stones were examined by XRD (X-ray diffractometer), XRF (X-ray fluorescence spectrometer), TG-DTA and SEM (Scanning Electron Microscope). The chemical compositions of the raw ore showed 71.75 wt%$SiO_2$, 22.10 wt%$Al_2O_3$, 1.86 wt%CaO, 2.97 wt%$K_2O$, 0.62 wt%$Fe_2O_3$. When pottery stone of 3 mm size was leached at $80^{\circ}C$ with 10 % oxalic acid, the content of $Fe_2O_3$ was reduced from 0.62 wt% to 0.24 wt% and the whiteness was enhanced. Grinding of pottery stone was conducted by a planetary ball mill using media of zirconia, the average particle size was 2～5 $\mu\textrm{m}$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.118-123
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• 2017

To manufacture MG-Si (Metallurgical grade silicon) for use in various industries, Acid leaching experiments were performed to remove aluminum (Al) and iron (Fe), which are the most common impurities found in the silicon raw material. The silicon raw material was reacted with five types of acids (HCl, HF, H2SO4, HNO3, H3PO4) at 1, 2, 4, and 6M; 1M HF showed the highest Al and Fe removal rates, 97.9% and 95.2%, respectively. HF, however, resulted in an 18% reduced yield due to the silicon corrosion properties. To minimize the yield reduction, 2M HCl, which has a second removal ratio result, was mixed with 1M HF and applied to the silicon raw material. The experiment was conducted to select the optimal conditions for the mixed solution, which were $80^{\circ}C$ and 2hr. Under the optimal conditions, the residual Al and Fe concentrations were 141 ppmw and 93 ppmw, respectively, and it very easy to produce MG-Si with 3N grade purity.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.305-311
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• 2002

Acetyl xylan esterase gene (AXE) from Aspergillus ficuum was cloned and its Pichia expression plasmid, pPICZ$\alpha$C-AXE (4.6 kb), was constructed, in which the AXE gene was under the control of the AOXI promoter and connected downstream of mating factor u-1 signal sequence. The plasmid linearized by Sacl was integrated into the 5'AOXI region of the chromosomal DNA of P. pastoris. In the flask batch culture of P. pastoris transformant on methanol medium, the cell concentration and total AXEase activity reached at 6.0 g-dry cell weight/1 and 77 unit/ml after 36 h cultivation, respectively. In the fed-batch culture employing the optimized methanol and histidine feeding strategy, the cell concentration and total AXEase activity were significantly increased to about 97 g-dry cell weight/1 and 930 unit/ml. Most of AXEase activity (>90%) was found in the extracellular medium and the majority of extracellular protein (>80%) was AXEase enzyme (33.5 kDa). This result means that about 9.8 g/1 of AXEase protein was produced in the extracellular medium.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.107-110
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• 1992

In order to study the prediction of shelf-life and the relation between the initial reducing sugar content (So) and the fermentation period (T) to produce 0.75% acid in kimchi, kimchis were prepared with Chinese cabbage from which fermentable sugars were removed by 0%, 30%, 50%, 74. In kimchis with 2.3%, 0.97%, 0.60%: initial reducing sugar content, fermentation periods to produce 0.75% acid took 2, 7, 12 days, respectively. This relation can be expressed as the following equation; T= -16.82 LogSo+7.66. Kimchi with cabbage removed by about 80% fermentable sugar showed out about 0.8% total acidity during 30 days's storage at $25^{\circ}C$.

• Journal of the Korean Wood Science and Technology
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• v.38 no.3
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• pp.242-250
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• 2010

The aim of this study was to investigate the terpenoids of Total Volatile Organic Compounds (VOCs) released during drying of Cryptomeria japonica using the thermal extractor (TE). Considering the drying process of C. japonica, temperatures of TE were set at $27^{\circ}C$, $60^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$, and $120^{\circ}C$, respectively. As the result, the emission factors of VOCs and terpenoids were increased as temperature increased. The amount of terpenoids included in VOCs emission factors were 87.5%, 81.6%, 83.6%, 90.1%, and 97.3% depending on above temperatures, respectively. Especially at$100^{\circ}C$ and $120^{\circ}C$, the amount of terpenoids were measured more than 90%. ${\delta}$-cadinene was the highest yield at each temperature and 32 types of terpenoids were collected. Emitted terpenoids were classified into the sesquiterpene group which consists of 15 carbon sources. These 32 sesquiterpenes were used for determining the useful bioactivity such as antifungal activity by the agar dilution. As the result, they showed the antifungal activity against Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum gypseum. The 5,000 ppm concentration of terpenoids showed a strong activity with 100% against the 3 fungi. At the 1,000 ppm concentration of terpenoids, the antifungal activities against three fungi were 95.2%, 98.7%, and 97.3%, and their activities were a little inhibited at 100 ppm concentration.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.1
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• pp.83-89
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• 2007

A biological anoxic-aerobic reactor filled with porous media was operated in lab scale for the advanced wastewater treatment. The experiments were conducted for 6 months with three HRTs (4, 6, 8hr) and temperature of $23{\sim}25^{\circ}C$. Some other experimental conditions were as follows; nitrification reactor (MLSS 4,500mg/L, DO 3.3mg/L, $23{\sim}28^{\circ}C$), denitrification reactor(MLSS 8,000mg/L, ORP -100mV, Temp.$19{\sim}23^{\circ}C$). Average removal efficiencies of SS, $BOD_5$, $COD_{Cr}$, T-N, and T-P were 97.8%, 95.5%, 94.5%, 80.2%, and 60.6%, respectively. The reactor filled with porosity media showed stable removal capacity for organics and nutrients. Fast and complete nitrification and denitrification were accomplished. Maintaining high MLSS with porous media in the nitrification and denitrification reactor appears to enhance the nitrogen removal process. For the higher T-P removal, some coagulant addition process will be needed.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.126-132
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• 2015

Three different methods (simple washing of plastic and pulp sample, washing after direct heating of the diapers, and the heating after washing of plastic and pulp sample) were carried out to decrease total coliforms and heterotrophic plate count (HPC) in the diaper's plastic and pulp. Plastic and pulp samples were obtained from diaper by treatment with 10% $CaCl_2$ and 4% sea salt water, dilution with 1,000 ml tap water, and draining by using sieves. Three times washing was the most appropriate for the reduction of microorganisms in plastic and pulp. By three times washing, the number of total coliforms in the plastic and pulp samples showed 92.8% and 99.8% of decrease, respectively, and the number of HPC showed 97.3% of decrease in the plastic and 98.5% of decrease in the pulp. The washing after direct heating of the fecal contaminated diapers was not effective because HPC in the plastic and pulp samples were still detected about 2-3 log CFU/g in the plastic and 1-2 log CFU/g in the pulp, respectively, even after heating at $60^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$ for 12 h. Meanwhile, total coliforms and HPC were completely sterilized at $80^{\circ}C$ for 4 h by heating after washing of plastic and pulp samples, suggesting that this method was the most appropriate method for the reduction of microorganisms in plastic and pulp obtained from fecal contaminated diapers.