• The Korean Journal of Mycology
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• v.32 no.2
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• pp.95-100
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• 2004

The main objectives of the study were to investigate cultural characteristics of Phellinus linteus. The optimum culture media for mycelial growth of P. linteus were MYA (malt yeast agar) and SMS (soybean powder malt Sucrose). Similarly, optimum temperature and pH were $30^{\circ}C$ and 6.0, respectively. Malt extract (2%, v/v) and yeast extract (0.2%, v/v) were optimum carbon and nitrogen sources. Similarly, 0.1% $KH_2PO_4$ was optimum mineral salt. Highest mycelial growth was observed when C/N ratio was 10 : 1. Optimum inoculum amount for flask culture was $5{\sim}6$ mycelial discs (6 mm diameter) per 100 ml of liquid medium, Highest mycelial dry weight was obtained when cultured in 100 ml liquid medium in 300 ml shaking flask after 20 days of shaking culture, For mass liquid culture (8 l), flask culture was homogenized and used as an inoculum. Optimum culture period and aeration rate for 8l fermentation culture were 12 days and 2.0 vvm, respectively.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.485-490
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• 2005

Effects of gas injectino on the copper recovery form industrial waste water in a fluidized-bed electrolytic reactor were investigated. Effects of gas injection on the individual phase holdup and efficiency of copper recovery for given operating variables such as liquid and gas velocity (0.1~0.4 cm/s), current density ($2.0{\sim}3.5A/dm^2$) and amount of fluidized solid particles (1.0~4.0 wt%) were examined. The solid particle, whose diameter and swelling density were 0.5 mm and $1100kg/m^3$, respectively, was made of polystylene and divinyl benzene. It was found that the holdup of gas and solid phases increased, but that of the liquid phase decreased with increasing velocity of gas injected into the reactor. With increasing gas and/or liquid velocity and increasing amount of fluidized particles is not needed, the rate of copper recovery increased to a maximum value of and subsequently decreased. The recovery rate of copper increased almost linearly with increasing current density in accordance with Faraday's law.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1125-1131
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• 1996

Ca or Sr-doped $PrMnO_3$ were prepared for cathode material of solid oxide fuel cell. The characteristics such as the electrical conductivity and the cathodic overpotential were investigated as to doping contents. Also the reactivity with yttria stabilized zirconia of electrolyte, and the thermal expansion coefficient were studied. The prepared perovskite powder had the mean particle size of $2{\sim}5{\mu}m$, and the particle size and the surface area was out of relation to the doping content. When Ca doping amount of electrode material was 30mol%, the electrical conductivity was the highest value of $266S{\cdot}cm^{-1}$ at $1000^{\circ}C$, and also the polarization characteristics showed the best property. The reactivity between YSZ and Ca-doped $PrMnO_3$ at $1200^{\circ}C$ for 100hours was lower than that between YSZ and Sr-doped $PrMnO_3$. The thermal expansion coefficient of $Pr_{0.7}Ca_{0.3}MnO_3$ was $1.19{\times}10^{-5}K^{-1}$ in the temperature range of $300{\sim}1000^{\circ}C$, and this value was similar to that of YSZ, $1.15{\times}10^{-5}K^{-1}$.

• The Korean Journal of Mycology
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• v.21 no.2
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• pp.94-105
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• 1993

The genus Cordyceps known as an insect parasite forms a sclerotium in insect bodies and then produces perithecia on the single or multiple stromata produced from sclerotium. Collected Cordyceps were identified into 5 species: Cordyceps militaris, C. nutans, Cordyceps sphecocephala, Isaria japonica, and Torrubiella sp. The fruit bodies of Cordyceps in petri-dish cover were fixed by tape and put the lid on water agar plates to isolate these collected Cordyceps. The germinated spores were transferred from water agar to Potato dextrose agar(PDA) after six hours. Mycelial growth of C. nutans and C. militaris was the most successful on Hamada media and was also good on Complete media and PDA. Mannose as a carbon source was good for two species and Glutamic acid as a nitrogen source was satisfactory to C. militaris and Asparagine gave a good result to C. nutans. C. militaris and C. nutans showed similar mycelial growth rate on the media that contained thiamine-HCI, biotine or nicotinic acid as a vitamine. When conidia of C. nutans were inoculated to insects, mortality was high in Artogeia napi L, Hemiptera, Plutella xylostella and 50% in Orthoptera, 12% in Acantholyda posticalise M, but not Agelastica coerulea B. in Aphididae, C. nutans was collected from only Hemiptera in nature, but killing effect on other insects was proved. Mycelial growth and fruit-body formation were good on the media that consist of rice powder 5g, wheat flour 5g, water 100ml, but formed fruit-body was not complete stromata but a mass of conidia according to results of observing microscope.

• Korean Journal of Materials Research
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• v.22 no.11
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• pp.569-574
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• 2012

Large single grain $Gd_{1.5}Ba_2Cu_3O_{7-y}$ (Gd1.5) bulk superconductors were fabricated by a top-seeded melt growth (TSMG) process using an $NdBa_2Cu_3O_{7-y}$ seed. The seeded Gd1.5 powder compacts with a diameter of 50 mm were subjected to the heating cycles of a TSMG process. After the TSMG process, the diameter of the single grain Gd1.5 compact was reduced to 43 mm owing to the volume contraction during the heat treatment. The superconducting transition temperature ($T_c$) of the top surface of the single grain Gd1.5 sample was as high as 93.5 K. The critical current densities ($J_cs$) at 77 K and 1T and 1.5 T were in ranges of 25,200-43,900 $A/cm^2$ and 10,000-23,000 $A/cm^2$, respectively. The maximum attractive force at 77 K of the sample field-cooled using an Nd-B-Fe permanent magnet (surface magnetic field of 0. 527 T) was 108.3 N; the maximum repulsive force of the zero field-cooled sample was 262 N. The magnetic flux density of the sample field-cooled at 77 K was 0.311T, which is approximately 85% of the applied magnetic field of 0.375 T. Microstructure investigation showed that many $Gd_2BaCuO_5$ (Gd211) particles of a few ${\mu}m$ in size, which are flux pinning sites of Gd123, were trapped within the $GdBa_2Cu_3O_{7-y}$ (Gd123) grain; unreacted $Ba_3Cu_5O_8$ liquid and Gd211 particles were present near the edge regions of the single grain Gd1.5 bulk compact.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.192-201
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• 1985

Two experiments, utilizing 204 broiler chicks of the Maniker strain, were conducted to study the effects of dried whey and chitin on the growth of chicks. In the first experiment, diets containing 5%, 10%, or 15% dried whey, or a control diet with no whey, were fed to chicks from 1 day to 4 weeks of age. There were no significant differences among the dietary groups, with respect to the rate of growth or protein or feed efficiency. In the second experiment, chicks were fed with diets containing no whey, 2% chitin, 20% dried whey, or 20% dried whey plus 2% chitin, from 1 day to 4 weeks of age. Adverse effects (diarrhea, crooked toes and enlarged cecum) were observed in the group fed 20% dried whey. The protein efficiency ratio (PER) and feed efficiency ratio (FER) tended to improve in the dietary groups with dried whey, as compared to the control group. No significant differences were observed in the total carcass nitrogen and lipid levels of dietary groups. But the chitin-supplemented diets tended to improve on the growth rate compared to the groups without chitin. The results of the two experiments suggest that the growing broiler chick can tolerate up to 15% dried whey in the diet, without any harmful effect on growth. Also, chitin may improve the poorer growth rate of chicks fed dried whey, but not all of the adverse effects of whey.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.363-370
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• 2016

Lightweight geopolymers are more readily produced and give higher fire resistant performance than foam cement concrete. Lowering the density of solid geopolymers can be achieved by inducing chemical reactions that entrain gases to foam the geopolymer structure. This paper reports on the effects of adding different concentrations of aluminum powder on the properties of cellular structured geopolymers. The apparent density of lightweight geopolymers has a range from 0.7 to $1.2g/m^3$ with 0.025, 0.05 and 0.10 wt% of a foaming agent concentration, which corresponds to about 37~60 % of the apparent density, $1.96g/cm^3$, of solid geopolymers. The compressive strength of cellular structured geopolymers decreased to 6~18 % of the compressive strength, 45 MPa of solid geopolymers. The microstructure of geopolymers gel was equivalent for both solid and cellular structured geopolymers. The workability of geopolymers with polyprophylene fibers needs to be improved as in fiber-reinforced cement concrete. The lightweight geopolymers could be used as indoor wall tile or board due to fire resistance and incombustibility of geopolymers.

• Journal of the Korean Electrochemical Society
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• v.7 no.1
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• pp.38-43
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• 2004

Porous carbon aerogel-silica gel composite materials were used as the electrodes of capacitive deionization(CDI) process, which were prepared by a paste rolling method. The electrochemical parameters such at current values, coulombs af a function of cycle, and CDI efficiencies were investigated for 10th and 100th cycles in 1,000ppm NaCl solution. Carbon aerogel-silica gel composite electrodes showed good wet-ability and higher mechanical strengths even under the NaCl solutions as well. In our experimented runs, all of the composite electrodes also are showed good cycle-ability without destroy of active material during cycles and decreased manufacturing times by $50\%$. Conclusively, the adding of silica gel powder to carbon aerogel leads to the effective performance of CDI process due to effective utilization of active materials by increasing the wet-ability and mechanical hardness.

• Journal of Sericultural and Entomological Science
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• v.49 no.1
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• pp.8-13
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• 2007

Natural indigo colorants were prepared by extraction of Polygonum tinctorium which was harvested just in the blooming season(in the late of July). The components were analyzed by TLC and HPLC, and its structures were analyzed by FT-IR, EI-mass. The results obtained are summarized as follows; The natural indigo powder was dissolved in DMSO and developed in eluent, $CHCI_3/CH_3CN$(8.5:1.5 v/v) by means of TLC for its quality analysis. It was segregated into indirubin as a red colour and indigo as a blue colour. In case of HPLC analysis,. FT-IR spectrum of indirubin showed a peak for NH residue between 3200 and $3300cm^{-1}$. $^1H-NMR$ spectrum for indigo displayed AA'BB' spin system caused by indole structure between 6.5 and 7.7ppm of H4, 5, 6 and 7, and -NH proton for indirubin showed an singlet between 10.88 and 11.0ppm. EI-mass spectrum of indigo and indirubin both disclosed their molecular size as 262 and it implies that these two substances are isomer.

• Journal of Ginseng Research
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• v.43 no.1
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• pp.125-134
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• 2019

Background: Excessive stress causes varied physiological and psychological disorders including male reproductive problems. Here, we attempted to investigate the protective effects of Korean Red Ginseng (Panax ginseng Meyer; KRG) against sub-acute immobilization stress-induced testicular damage in experimental rats. Methods: Male rats (age, 4 wk; weight, 60-70 g) were divided into four groups (n = 8 in each group): normal control group, immobilization control group, immobilization group treated with 100 mg/kg of KRG daily, and immobilization group treated with 200 mg/kg of KRG daily. Normal control and immobilization control groups received vehicle only. KRG (100 mg/kg and 200 mg/kg) was mixed in the standard diet powder and fed daily for 6 mo. Parameters such as organ weight, blood chemistry, sperm kinematic values, and expression levels of testicular-related molecules were measured using commercially available kits, Western blotting, and reverse transcription polymerase chain reaction. Results: Data revealed that KRG restored the altered testis and epididymis weight in immobilization stress-induced rats significantly (p < 0.05). Further, KRG ameliorated the altered blood chemistry and sperm kinematic values when compared with the immobilization control group and attenuated the altered expression levels of spermatogenesis-related proteins (nectin-2, cAMP responsive element binding protein 1, and inhibin-${\alpha}$), sex hormone receptors (androgen receptor, luteinizing hormone receptor, and follicle-stimulating hormone receptor), and antioxidant-related enzymes (glutathione S-transferase m5, peroxiredoxin-4, and glutathione peroxidase 4) significantly in the testes of immobilization stress-induced rats. Conclusion: KRG protected immobilization stress-induced testicular damage and fertility factors in rats, thereby indicating its potential in the treatment of stress-related male sterility.