• Journal of Biosystems Engineering
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• v.24 no.2
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• pp.107-114
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• 1999

To find the best combustion conditions in the heavy oil burner kinetic viscosity of heavy oil A, B and C at different temperature range, from 40 to 140$^{\circ}C$, and the droplet sizes of the heavy oils at different temperature and pump pressure were measured. And, combustion characteristics were investigated under the different conditions : two different heavy oil and three different oil temperature. At temperature of 70, 100, 130$^{\circ}C$ the kinetic viscosity of heavy oil A and B are 7.9, 5.7, 4.3 and 30.4, 13.7, 7.9cSt, respectively. The greatest and smallest viscosity were 7,455 cSt at C oil on 27$^{\circ}C$ and 4.26cSt at A oil on 140$^{\circ}C$. The magnitude of viscosity difference between at 100$^{\circ}C$ and 140$^{\circ}C$ under 6 cSt in cases of A and B oil, but more than 30cST on C oil. Of the droplet sizes, the biggest and smallest droplet size in A oil were 98$\mu\textrm{m}$ at oil temperature of 130$^{\circ}C$(4.3cSt), pump pressure of 1.57MPa and 72$\mu\textrm{m}$ at 70$^{\circ}C$(7.9cSt), 2.35MPa, respectively. It appeared that as spraying pressure increased the droplet size decreased, however, no distinct differences were found in the effects of kinetic viscosity on the droplet sizes of the test range. The best combustion performance was observed when droplet size, spraying pressure and oil temperature were 73$\mu\textrm{m}$, 2.35MPa and 70$^{\circ}C$ producing CO2 of 13.1%, CO of 13ppm and flue gas temperature of 250$^{\circ}C$ in A oil combustion For B oil, it was100$^{\circ}C$, 2.35MPa, 52$\mu\textrm{m}$, producing CO2 of 10ppm and flue gas temperature of 260$^{\circ}C$. In general, it appeared that better combustion results were observed in the smaller droplets produced burner condition.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.349-354
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• 2013

This study examined a technique for cooling root zone aimed at lowering substrate temperature for sweet pepper (Capsicum annum L. 'Orange glory') cultivation in coir substrate hydroponics during hot season, from the $16^{th}$ of July to $15^{th}$ of October in 2012. The root zone cooling technique was applied by using an air duct (${\varnothing}12$ cm, hole size 0.1 mm) to blow cool air between two slabs during night (5p.m. to 3a.m.). Between the $23^{rd}$ of July and $31^{st}$ of August (hot temperature period), average daily substrate temperature was $24.7^{\circ}C$ under the root zone cooling, whereas it was $28.2^{\circ}C$ under condition of no cooling (control). In sunny day (600~700 W $m^{-2}{\cdot}s^{-1}$), average substrate temperatures during the day (6a.m. to 8p.m.) and night (8p.m. to 6a.m.) were lower about $1.7^{\circ}C$ and $3.3^{\circ}C$, respectively, under the cooling treatment, compared to that of control. The degree of temperature reduction in the substrate was averagely $0.5^{\circ}C$ per hour under the cooling treatment during 6p.m. to 8p.m.; however, there was no decrease in the temperature under the control. The temperature difference between the cooling and control treatments was $1.3^{\circ}C$ and $0.6^{\circ}C$ in the upper and lower part of the slab, respectively. During the hot temperature period, about 32.5% reduction in the substrate temperature was observed under the cooling treatment, compared to the control. Photosynthesis, transpiration rate, and leaf water potential of plants grown under the cooling treatment were significantly higher than those under the control. The first flowering date in the cooling was faster about 4 days than in the control. Also, the number of fruits was significantly higher than that in the control. No differences in plant height, stem thickness, number of internode, and leaf width were found between the plants grown under the cooling and control, except for the leaf length with a shorter length under the cooling treatment. However, root zone cooling influenced negligibly on eliminating delay in fruiting caused by excessively higher air temperature (> $28^{\circ}C$), although the substrate temperature was reduced by $3^{\circ}C$ to $5.6^{\circ}C$. These results suggest that the technique of lowering substrate temperature by using air-duct blow needs to be incorporated into the lowering growing temperature system for growth and fruit set of health paprika.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.32-37
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• 1997

The rate constants and activation energies for formation of two chemical markers, M-1 and M-2 at sterilization temperatures were determined in a meatball system. Destruction rates for bacterial spores were also determined. The rate constants for M-1 and M-2 formation at $121^{\circ}C$ were 0.03 and 0.28 Abs/min, respectively. The activation energies for M-1 and M-2 were 27.9 and 24.6 Cal/mol. M-2 was formed faster than M-1 and reached a maximum and decreased. M-1 formation continued up to 30 min at $121^{\circ}C$ and 10 min at $131^{\circ}C$, which makes M-1 a more useful chemical marker for high $F_0$ values. The D-values for spores (B. stearothermophilus ATCC 12980) at 111, 114.4, 117.7 and $121^{\circ}C$ were 7.5, 4.5, 1.9 and 0.58 respectively. At temperatures between 111 and $121^{\circ}C$, there was a liner correlation between destruction of the spores and the M-1 formation. It was difficult to get accurate D-value at $126^{\circ}C\;and\;131^{\circ}C$, because almost all spores were dead before temperature at the center of the meatball reached $126^{\circ}C$. These data suggest that the chemical marker should be used to evaluate overprocessing as well as microbial lethality in aseptic processing.

• Food Science and Preservation
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• v.10 no.3
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• pp.293-296
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• 2003

This study was carried out to obtain physical characteristics of paper board and to measure bulge of 1,000 mL carton pak by different storage conditions. Water holding capacity of paper boards were mean of 5.6～7.0％, stiffness of machine direction(MD) was 243.3～266.7 g/cm and cross direction(CD) was 99.2～109.2 g/cm, respectively. The weight of 1,000 mL carton pak were in the range of 29.17～31.26 g. The bulge of carton paks were 6.33～6.93 mm after 7 days at 6$^{\circ}C$ storage, 7.26～8.56 mm after 7 days at 10$^{\circ}C$ and was 8.66 mm after 7 days at 10$^{\circ}C$ treated with 1 hour heat shock per day, respectively. According to this result, the bulge length of 1,000 mL carton pak was showed increased pattern upon increasing the storage temperature and the order was 6$^{\circ}C$ < l0$^{\circ}C$ < 10$^{\circ}C$＋ heat shock. To prevent bulge occurence, it was thought to control storage temperature and humidity of paper board or carton pak and to minimize their shock on cold chain system after filling process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2924-2932
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• 2015

This study is for estimate the amount of water supplied data to get a database for economic plan of water supply system by survey for the amount of water supplied of primary, middle and highschool. For this, 54 of primary school, middle school, high school in 6 cities of Kangwon for 5 years. As a result, average of the amount of water supplied per month is $600.7m^3/mon$ and primary, middle schools are $484.2m^3/mon$ and high schools are $833.8m^3/mon$. Average of the amount of water supplied per class is $27.0m^3/mon/class$ and primary, middle schools are $24.4m^3/mon/class$ and high schools are $32m^3/mon/class$. Average of the amount of water supplied per person per day is 55.8l/c/d and primary school, middle schools are 54.4l/c/d and high schools are 58.6l/c/d.

• Journal of Magnetics
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• v.10 no.3
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• pp.84-88
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• 2005

Nanoparticles $Ni_{0.7}Zn_{0.3}Fe_2O_4$ is fabricated by a sol-gel method. The magnetic and structural properties of powders were investigated with XRD, SEM, $M\ddot{o}ssbauer$ spectroscopy, and VSM. $Ni_{0.7}Zn_{0.3}Fe_2O_4$ powders annealed at $300^{\circ}C$ have a spinel structure and behaved superparamagnetically. The estimated size of $Ni_{0.7}Zn_{0.3}Fe_2O_4$ nanoparticle is about 11 nm. $Ni_{0.7}Zn_{0.3}Fe_2O_4$ annealed at 400 and $500^{\circ}C$ has a typical spinel structure and is ferrimagnetic in nature. The isomer shifts indicate that the iron ions were ferric at the tetrahedral (A) and the octahedral (B). Blocking temperature $(T_B)\;of\;Ni_{0.7}Zn_{0.3}Fe_2O_4$ nanoparticle is about 260 K. The magnetic anisotropy constant of $Ni_{0.7}Zn_{0.3}Fe_2O_4$ annealed $300^{\circ}C$ were calculated to be $1.7X10^6\;ergs/cm^3$. Also, temperature of the sample increased up to $43^{\circ}C$ within 7 minutes under AC magnetic field of 7 MHz.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5644-5651
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• 2014

Propolis is an extremely safe natural antimicrobial substance that has been reported to have powerful antibacterial efficacy. The aim of this study was to evaluate the inhibitory effects of propolis against Candida albicans (C. albicans). Propolis was collected from the honey bee Apis mellifera. The strain of C. albicans was cultivated overnight in liquid media incubated at $37^{\circ}C$. The antimicrobial activity was investigated using phosphate buffered saline (PBS), 3% sodium hypochlorite (NaOCl), 0.1% chorhexidine (CHX), and propolis extracts ($5{\mu}l/ml$, $10{\mu}l/ml$). C. albicans were sensitive to 3% NaOCl, 0.1% CHX, and propolis ($5{\mu}l/ml$, $10{\mu}l/ml$) with zones of inhibition of 15, 14.5, 16, and 17 mm, respectively. The CFU of PBS, 3% NaOCl, 0.1% CHX, $5{\mu}l/ml$ and $10{\mu}l/ml$ of propolis led a 1, 7, 7, 5 and 7-log reduction. Among the groups tested, C. albicans was most sensitive to $10{\mu}l/ml$ of propolis, which showed the largest inhibition zones. Therefore, propolis can be a new antimicrobial therapy for oral mucosa disease in traditional medicine.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.757-761
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• 2003

Spatial distribution and biomass of commercial shellfish were investigated in the Saemangeum tidal flat on the west coast of Korea during August 1999. Thirteen species of shellifsh were collected. Major dominant species of the study area were Umbonium thomasi with a density of $6.7\;ind.{\cdot}m^{-2}\;(38.2\%)$, Mactra veneriformis with $6.6\;ind.{\cdot}m^{-2}\;(37.4\%)$ and Reticunassa festiva with $1.3\;ind.{\cdot}m^{-2}\;(7.2\%)$. Commercially important species such as M. veneriformis ($90.7\;ind.{\cdot}m^{-2}\;69.3\%$), M. lusoria ($15.6\;ind.{\cdot}m^{-2}\;11.9\%)$), C. sinensis ($8.7\;ind.{\cdot}m^{-2}\;6.7\%)$) were dominant in total weight. Most of the shellfish were distributed between the mid-littoral and sub-littoral zones, but C. sinensis and L. flexuosa were distributed mainly in the polluted areas of the supra-littoral zone. The spatial distribution pattern of each shellifsh species generally resembles the Mangyeong and Dongjin estuary. Biomass of commercially important species, M. veneriformis, M. lusoria, C. sinensis and Ruditapes philippinarum in the tidal flat (ca. 850 ha) was estimated to be 774, 135, 67 and 10 tons, respectively.

• Applied Biological Chemistry
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• v.35 no.3
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• pp.170-172
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• 1992

Four types of polyphenol oxidase were isolated from the crude extract of a Ligularia fischeri by gel filtration on Sephadex G-150. Optimum pH and temperature for the activity of partially purified enzyme were 7.5 and $25^{\circ}C$, respectively. It was stable at temperature $40^{\circ}C$ when examined at pH 7.5 for 5 min, and lost 90% of its activity at $70^{\circ}C$ in 30 min at pH 7.5. The enzyme has good activity on catechol and chlorogenic acid but was inactive on dopamine.

• Journal of the Korean Chemical Society
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• v.38 no.3
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• pp.200-207
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• 1994

A biosensor for the measurement of L-glutamine has been constructed by immobilizing the slice of Wistar rat kidney and it's organelle on $NH_3$ gas-sensing electrode. The effects of pH, buffer solution, temperature and thickness of slice were investigated in order to optimize electrode response. The tissue sensor had the linearity in the range of L-glutamine concentration $8.0{\times}10^{-5}{\sim}1.0{\times}10^{-2} M$ with a slope of 53.8 mV/decade in 0.05 M phosphate buffer solution, pH 7.8 at $30^{\circ}C$, and optimum thickness of slice and response time were 30 ${\mu}m$ and 3∼5 min, respectively. The organelle sensor showed the linearity within L-glutamine concentration range of $1.2{\times}10^{-4}{\sim}5.0{\times}10^{-3} M$ with a slope of 54.0 mV/decade in 0.05 M phosphate buffer solution, pH 7.8 at $30^{\circ}C$, and response time was 6∼7 min, respectively. Thus, it is clear that the tissue and organelle sensor will be useful for L-glutamine measurements.