• Journal of the Korean Physical Society
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• v.73 no.11
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• pp.1703-1707
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• 2018

Ferromagnetic ${\tau}-phase$ $Mn_{54}Al_{46}C_{2.44}$ particles were synthesized, and its composites with commercial $Sm_2Fe_{17}N_3$ and synthesized $Fe_{65}Co_{35}$ powders were fabricated. Smaller grain size than the single domain size of the $Mn_{54}Al_{46}C_{2.44}$ without obvious grain boundaries and secondary phases is the origin for the low intrinsic coercivity. It was confirmed that the magnetic properties of the $Mn_{54}Al_{46}C_{2.44}$ can be enhanced by magnetic exchange coupling with the hard magnetic $Sm_2Fe_{17}N_3$ and soft magnetic $Fe_{65}Co_{35}$. The high degrees of the exchange coupling were verified by calculating first derivative curves. Thermo-magnetic stabilities of the composites from 100 to 400 K were measured and compared. It was demonstrated that the $Mn_{54}Al_{46}C_{2.44}$ based composites containing $Sm_2Fe_{17}N_3$ and $Fe_{65}Co_{35}$ could be promising candidates for future permanent magnetic materials with the proper control of purity, magnetic properties, etc.

• Journal of Microbiology
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• v.35 no.4
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• pp.295-299
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• 1997

Pseudomonas sp. S-47 is capable of transforming 4-chlorobenzoate to 4-chlorocatechol which is subsequently oxidized bty meta-cleavage dioxygenase to prodyce 5-chloro-2-hydroxymuconic semialdehyde. Catechol 2,3-dioxygenase (C23O) produced by Pseudomonas sp. S-47 was purified and characterized in this study. The C23O enzyme was maximally produced in the late logarithmic growth phase, and the temperature and pH for maximunm enzyme activity were $30{\sim}35^{\circ}C$ and 7.0, respectively. The enzyme was purified and concentrated 5 fold from the crude cell extracts through Q Sepharose chromatography and Sephadex G-100 gel filtration after acetone precipitation. The enzyme was identified as consisting of 35 kDa subunits when analyzed by SDS-PAGE. The C23O produced by Pseudomonas sp. S-47 was similar to Xy1E of Pseudomonas putida with respect to substrate specificity for several catecholic compounds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.152-157
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• 1997

A nereid polychaete, Nicon sinica Wu and Sun, 1979, was newly recorded in Korean fauna. The specimens were collected in the mud bottom by a dredge in Yellow Sea, Korea. The species was described with figures, and the key to genera was revised. Adding this Nicon sinica, a total of 34 species representing 13 genera are known to the Korean nereid polychaetes.

• Food Science of Animal Resources
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• v.35 no.1
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• pp.10-18
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• 2015

The changes in fatty acid composition of total intramuscular lipid and phospholipids were investigated in the longissimus dorsi, left-hind leg muscle, and abdominal muscle of male Ira rabbits. Changes were monitored at 35, 45, 60, 75, and 90 d. Analysis using gas chromatography identified 21 types of fatty acids. Results showed that the intramuscular lipid increased and the intramuscular phospholipids (total intramuscular lipid %) decreased in all muscles with increasing age (p<0.05). An abundant amount of unsaturated fatty acids, especially polyunsaturated fatty acids, was distributed in male Ira rabbits at different ages and muscles. Palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), and arachidonic acid (C20:4) were the major fatty acids, which account to the dynamic changes of the n-6/n-3 value in Ira rabbit meat.

• The Korean Journal of Malacology
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• v.25 no.3
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• pp.179-187
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• 2009

The effects of water temperature and salinity on embryonic development and spat survival of mussel Musculista senhousia were investigated. Embryos were incubated in water ranging from 0 to $35^{\circ}C$ and with salinity from 5‰ to 40‰. Mussel spat were tested in water from 0 to $40^{\circ}C$ and with salinity from 0‰ to 100‰. The optimal conditions for mussel embryos were $20-25^{\circ}C$ and salinity from 25‰ to 35‰, based on Within this temperature range, higher temperatures correponded to a shorter duration of the embryonic period. Optimisation of mussel spat survival was at $25-35^{\circ}C$ and salinity from 30‰ to 40‰; both values are higher than those for embryo, which hinted M. senhousia embryos are more vulnerable than spat. Temperatures below $15^{\circ}C$ were lethal for embryos, making temperature a feasible method with which to control the large population of M. senhousia in ark-shell farm during its spawning period.

• Journal of Korean Society on Water Environment
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• v.27 no.5
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• pp.563-571
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• 2011

The purpose of this study is to investigate the high strength ammonia oxidation of piggery wastewater. Laboratory scale reactors was operated using influent of piggery wastewater and effluent of anaerobic digester from piggery wastewater at $35^{\circ}C$ and $20^{\circ}C$. Results of various operating conditions were compared and analyzed. After analyzing the results, effluent of anaerobic digester from piggery wastewater required shorter Solid retention time (SRT) than influent of piggery wastewater. In terms of the temperature, stable ammonia removal and denitrification was achieved on the both of the condition. At the temperature of $35^{\circ}C$, nitrite conversion rate was better than $20^{\circ}C$. It can be concluded that treating the piggery wastewater using anaerobic digester on the condition of the temperature at $35^{\circ}C$ is more efficient on the nitritation of the piggery wastewater.

• Journal of Animal Science and Technology
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• v.49 no.1
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• pp.33-40
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• 2007

This experiment was conducted to determine the effect of soybean oil, tallow and coconut oil supplementation on growth performance, serum lipid changes and nutrient digestibility in weaned pigs. One hundred twenty cross-bred [(Yorkshire×Landrace)×Duroc, 6.92±0.01kg average initial BW] were used in a 35 d growth trial. Dietary treatments included CON (5% soybean oil), T0.5 (4.5% soybean oil+0.5% tallow), C0.5 (4.5% soybean oil+0.5% coconut oil) and C1.0 (4.0% soybean oil+1.0% coconut oil). For the whole period and from d 14 to 35, G/F was increased in C0.5 and C1.0 treatments compared with T0.5 treatment (P<0.05). ADG and ADFI were not affected by treatments. On d 14, C1.0 treatment was higher in serum HDL-cholesterol than C0.5 treatment and atherogenic index was increased in C0.5 treatment compared to T0.5 and C1.0 treatments. Digestibility of fat was improved for pigs fed C1.0 diet compared with those fed T0.5 diet on d 35. However, there were no significant differences in digestibilities of DM, N and DE. In conclusion, feeding diets containing soybean and coconut oils in weaned pigs increased feed efficiency and fat digestibility than feeding those containing soybean oil and tallow.

• Korean Journal of Veterinary Research
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• v.15 no.1
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• pp.51-55
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• 1975

In this study two sets of experiments were undertaken. Firstly, the embryonated eggs and first-stage larvae, sprayed in disinfected soil, were exposed to different temperatures. Then, the viabilities of them were weekly determined by inoculating the soil to earthworms, Eisenia foetida. Secondly, the infective larvae, seperated from the earthworms and suspended in tap water, were also exposed to different temperatures and their viabilities were checked microscopically at weekly intervals. The results were summerized as follows: 1. The maximum longevities of embryonated eggs and first-stage larvae were determined as 1 week at $35^{\circ}C$, over 36 weeks at $25^{\circ}C$, $15^{\circ}C$, and $5^{\circ}C$, 32 weeks at $-5^{\circ}C$, and under 1 week at $-15^{\circ}C$. 2. The mean numbers of infective larvae detected from the test earthworms were greatest at $5^{\circ}C$, and decreased with rise or fall of the temperature. 3. Infective larvae freed from the intermediate host were able to survive for 2 weeks at $25^{\circ}C$ and 3 weeks at $15^{\circ}C$. However, they lost their viabilities in a week at $35^{\circ}C$, $5^{\circ}C$, $-5^{\circ}C$, and $-15^{\circ}C$. 4. The number of living infective larvae at $15^{\circ}C$ was greater than at $25^{\circ}C$.

• Journal of Bio-Environment Control
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• v.22 no.1
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• pp.13-18
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• 2013

This study was conducted to examine the effect of temperature and relative humidity (RH) that might affect the pollen germination rate and pollen tube length in oriental melon. The experiment was performed using three cultivars namely 'Mallijangseong', 'Ohbokggul', and 'Joeundae' wherein environmental conditions were controlled by three different temperatures $15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$ and also three RH levels 30%, 60%, and 90%. Based on the results in terms of temperature, true to all cultivars, plants exposed to $25^{\circ}C$ had the highest pollen germination rate while plants exposed to $15^{\circ}C$ had the lowest. Among the three cultivars, 'Mallijangseong' had the highest in terms of pollen germination rate, followed by 'Ohbokggul', and lastly was 'Joeundae' that showed the lowest germination rate. In the case of pollen tube length, pollen exposed under $35^{\circ}C$ showed the longest tube length, followed by pollen under $25^{\circ}C$, and pollen under $15^{\circ}C$ remarkably had the shortest tube length. Across the three cultivars 'Ohbokggul' had the longest pollen tube length. In the case of RH, pollen germination response among three cultivars depends on the humidity conditions but based on the results, there was no significant differences although high germination rate was observed in highest humidity condition. Between each cultivar, 'Ohbokggul' had the lowest pollen germination rate compared with 'Mallijangseong' and 'Joeundae' after exposure to different RH conditions wherein pollen germination showed significant differences among treatments. The pollen collected under 60% RH had the longest pollen tube length, followed by 30%, and the shortest was under 90% RH. In general, 'Ohbokggul' had the longest pollen tube length while 'Joeundae' had the shortest among the three cultivars.

• The Korean Journal of Malacology
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• v.31 no.1
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• pp.35-41
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• 2015

In order to investigate the live food value of microalgae for efficacious rearing of larvae and spats of bivalve, we studied growth rates of four microalgal species (Isochrysis galbana, Pavlova lutheri, Chaetoceros simplex, Tetraselmis tetrathele) cultured in different environmental conditions. These include changes in temperatures (20, 25, 30 and $35^{\circ}C$), salinities (20, 25, 30 and 33 psu) and light intensities (60, 100 and $140{\mu}mol\;m^{-2}s^{-1}$). The growth rate of I. galbana was faster at $25^{\circ}C$ than that of $20^{\circ}C$. At $25^{\circ}C$ the highest growth rate of I. galbana was observed at 33 psu (0.413) and the lowest at 20 psu (0.368) in 10 days of culture (P < 0.05). The growth rate of I. galbana was lower at 25 psu (0.383) than that of 30 psu and higher than that of 20 psu (P < 0.05). Similar temperature and salinity-dependent changes were also found in P. lutheri and T. tetrathele. C. simplex showed faster growth rate at $30^{\circ}C$ than that of $25^{\circ}C$. The highest growth rate of C. simplex was observed at 33 psu (0.428) and the lowest at 20 psu (0.389) in 10 days of culture (P < 0.05). Upon exposure to the light with different intensities, all four microalgal species showed a significantly faster growth rate at $140{\mu}mol\;m^{-2}s^{-1}$ than at $100{\mu}mol\;m^{-2}s^{-1}$ (P < 0.05).