• Journal of Sensor Science and Technology
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• v.11 no.1
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• pp.9-17
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• 2002

The forming conditions of X-ray storage phosrhors $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ have been investigated, and measured the PSL emission spectra and its intensity, fading characteristics and does dependence of the prepared phosphors. These characteristics were compared with those of commercial image plate (ST-III) obtained from Fuji Photo Film Co. The optimal preparing conditions of $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ Phosphor were 0.5 mol% of $EuF_3$, 4.0 mol% of NaF and composition ratio x=0.3, and the sintering temperature were $950^{\circ}C$ in $H_2$ atmosphere. When the composition ratio x was equal to 0, the spectral range of the luminescence of $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ phosphor was $365{\sim}420\;nm$, and its maximum luminescence intensity appeared at 390 nm. When composition ratio x was not equal to 0, the wavelength ranges and peak of the spectra were shifted to the longer wavelength with the growth of composition ratio x. A good linearity was shown between the PSL intensity and X-ray irradiation dose. The phosphor sample with x=0.3 exhibited better fading characteristics than that of other $BaFBr_{1-x}I_x:Eu^{2+}$ phosphor samples, and the fading characteristics of the PSL intensity at room temperature were shown poorer with increasing $I^-$ ion concentration. The lattice constant of the phosphor becomes larger with increasing the $I^-$ ion concentration.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.159-165
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• 2015

The aim of this study was to investigate microbiological contamination levels in the manufacturing company of ginseng products (white and red ginseng). Firstly, the contamination level for ginseng and each stage ginseng were 1.8~4.9 log CFU/g (total bacteria), 1.2~3.0 log CFU/g (coliform), 0.8~4.1 log CFU/g (fungi). However, only Bacillus cereus among pathogenic bacteria was detected from a few sample. The contamination of total bacteria tended to decrease as ginseng was being processing. Therefore, that of finished products (white and red ginseng) showed the lowest contamination level among each stage ginseng sample. That of fungi decreased steadily, although the contamination of fungi has tended to increase right after ginseng was steamed. Secondly, the contamination level for working tools and facilities were $1.7{\sim}4.7log\;CFU/cm^2$ (total bacteria), $0.4{\sim}4.0log\;CFU/cm^2$ (coliform), $0.9{\sim}4.2log\;CFU/cm^2$ (fungi). Especially, washing and peeling machines were higher contamination level. Finally, the contamination level of worker who washed and steamed ginseng was higher than worker who shaped, sorted and stored ginseng. Also, Staphylococus aureus was detected at 0.2~0.7 log CFU/hand on some wokers' hands. These results showed proper heating condition (temperature and time) and tidy manufacturing facility are the most important to avoid developing any microbiological problem of Ginseng Products.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.23-29
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• 1989

In order to investigate developmental habit and morphology of maize tillers, time and location of tiller development. number of tillers per plant, tiller angle, height and diameter of tillers and root systems of tillers were examined under field condition for maize with tillers. Materials used were mostly from Korean local lines and a few lines from other countries were also included for comparison. The time of the first tiller development was about 18 to 20 days after emergence when planted on May in Yusong. The second tiller appeared about 4 to 5 days after the first tiller appeared. The tiller number per plant varied with lines and hybrids and ranged from two to ten. The location of tiller development was usually basal nodes of the main stem. Each tiller appeared to have its own root system. The angle between tillers and main stem was variable depending upon the maizes and the tiller angle could be classified into three categories. The height of tillers was also variable and seemed to be under genetic control. The most productive tillers were found among the Korean local derivatives.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.30-39
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• 1989

Forage productivity of cropping systems of rye - silage corn, silage corn - oats, silage corn - rape was studied in the south-eastern part of Korea where rice black-streaked dwarf virus(RBSDV) infection of corn are severe. Rye(cv. Paldanghomil) was planted on Oct. 20 of 1986 and harvested 10 times from April 5 to May 5 at the 5-day intervals in 1987, corn (cv. Suweon 19 and Jinjuok) was planted 5 times from April 5 to May 15 at the 10-day intervals in 1987, and oats(cv. Megwiri) and rape (cv. Velox) were planted 4 times from Sept: 4 to 25 at the 7-day intervals and harvested 4 times from Nov. 10 to Dec. 10 at the 10-day intervals in 1987. Considering yield, nutrition value, and in vitro dry matter digestibility (IVDMD), forage productivity of the cropping systems was compared. As harvesting time of rye delayed, plant height, dry matter(DM) yield, percent DM, crude fiber, and digestible DM yield increased, but crude protein, crude fat, and IVDMD decreased. However, nitrogen free extract was not different among the harvesting dates. As planting date of corn delayed, RBSDV infection rate increased. but DM yield of silage decreased. However, silage yield of Jinjuok was higher, but RBSDV infection rate was lower compared with Suweon 19 at all planting dates. DM yield of oats and rape decreased as planting date delayed. However, at Sept. 4 and 11 plantings yield of oats on Nov. 10 was much lower than that of rape, but the differences in yield between two crops decreased with delayed harvesting, and yield was similar on Dec. 10. A cropping system harvesting rye around April 20 and followed by planting corn in late April was best among the rye-corn systems considering yield and nutrition value of both crops. However, among the corn-oats or corn-rape cropping systems early April planting of corn and followed by early Sept. planting of oats or rape showed best results with similar yield potential of the best rye-corn cropping system.

• Journal of Life Science
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• v.27 no.7
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• pp.754-759
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• 2017

The 100 l culture system was made on the basis of LED light, and Nannochloropsis oculata was cultured in f/2 medium at light intensity ($100{\mu}mol/m^2/s$), culture temperature ($20^{\circ}C{\pm}1^{\circ}C$) and LD cycle (12hr). As a result, the maximum biomass of 1.07 g/l was cultured as a result of 100 l mass culture at $100{\mu}mol/m^2/s$ and 24 mg/l nitrate concentration in LED blue (475 nm). The extraction was carried out using sonicator, homogenizer and chemical method 0.5M HCl shredding method. The contents of chlorophyll a, chlorophyll b and carotenoid were 1.6, 0.5 and 0.3 mg/g cell. When using homogenizer, it was measured at 1.0, 0.6 and 0.2 mg/g cell. The chemical breakdown method of 0.5M HCl, chlorophyll a, b, and carotenoid contents were measured as 0.9, 0.8, 0 mg/g cell. The highest amount of biomass during the distruption time was measured at 3.6 mg/g cell at 15 min disintegration and acetone, 3.6 mg/g cell of acetone, methanol, and ethanol were measured as effective solvents. Concentration was measured by using microfilter, disk type continuous centrifuge and tubular type continuous centrifuge were 16.0, 1.1 and 0.5 g/l, respectively. Four kinds of equipment such as hot air dryer, vacuum dryer, spray dryer and freeze dryer were tested to optimize the drying process. As a result, the recovery rates of spray dryer and freeze dryer were 80% and 60%.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.677-687
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• 1999

This study was performed to evaluate the effect of aging and thermal cycling on the tensile strength of six commercially available glass-ionomer materials: two chemically set glass-ionomer materials(Fuji II, Fuji IX), two resin-modified glass-ionomer materials(Fuji II LC, Vitremer), and two polyacid-modified composite resins(Compoglass, Dyract). Rectangular tension test specimens were fabricated in a teflon mold giving 5mm in gauge length and 2mm in thickness. All samples were divided into 3 groups. Group 1 was immersed in a $37^{\circ}C$ distilled water for 1 hour. Group 2 was immersed in a $37^{\circ}C$ distilled water for 30 days. Group 3 was subjected to 10,000 thermal cycles between $5^{\circ}C$ and $55^{\circ}C$, and the immersion time in each bath was 15 seconds per cycle. Tensile testing was carried out at a cross-head speed of 0.5mm/min and fracture surfaces were examined with scanning electron microscope. The results obtained were summarized as follows; 1. The polyacid-modified composite resins were stronger than the resin-modified glass-ionomer materials, which were much stronger than the conventional glass-ionomer materials. 2. Tensile strengths were slightly increased after aging treatments for 30days. 3. Tensile strengths of conventional glass ionomers were significantly increased after thermal cycling treatment(p<0.01). 4. The highest tensile strength value of 45.4MPa was observed in the Dyract group and the lowest value of 13.3MPa was observed in the Fuji II LC group after the thermal cycling test, and the strengths of polyacid-modified composite groups were significantly higher than those of other groups. 5. The highest characteristic strength value of 48.6MPa was obtained in the Dyract group, however the highest Weibull modulus value of 8.9MPa was obtained in the Compoglass group after thermal cycling test.

• Parasites, Hosts and Diseases
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• v.34 no.1
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• pp.69-78
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• 1996

This study was done to investigate the enzyme-histochemical localization and characteristics of alkaline and acid phosphatase related with metabolism in sparganum and adult of Spirometrn erinacei. By the enzyme-histochemical assay, the alkaline and acid phosphatases were localized in the tegument and subtegumental musculature of sparganum and adult, but not in the parenchyma. The activities of alkaline phosphatase were stronger in the tegument than in the subtegumental musculature, and activities of acid phosphatase were stronger in the tegument of adults than those of sparganum. The 2 isozymes of alkaline and acid phosphatases were separated from s-sparganum (from snake) and r-sparganum (from experimentaly infected rats) respectively but 4 isozymes of Alp and 3 isoxymes of Acp were separated from adult worms by electrophoresis. In isogyme Alp, the 661)a was the common isozyme, but 130 kDa isozyme of Acp was the common isozyme in spargana and adult worms. By isoelectrofocusing, 4 isozymes (PI 7.9, 7.7, 6.5 and 6.3) and 2 isozymes (PI 7.9 and 7.7) of alkaline phosphatase were separated from adults and spargana respectively. In the stability against heat, activity of alkaline phosphatase was denatured perfectly after heating at 90℃ for 40 seconds. The optimum pH and temperature for activity of alkaline phosphatase were about pH 10 and 50℃, respectively. The maximum activity (unit) of alkaline phosphatase was 22.0 in s- sparganum,25.0 in r-sparganum and 215.0 in adult worms, so that the maximum activity was revealed higher in adults than spargana. As the result from above, we observed that alkaline and acid phosphatases were functioned mainly in the tegument and subtegumental musculature , and the isoxymes of phosphatase were activated differently according to habitat of the parasites. The spargana and adult worms carry out the pafasitism by adapting thenlselves to parasitic circumstance loth these emxymes.

• Journal of Plant Biology
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• v.37 no.3
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• pp.387-394
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• 1994

Effects of environmental factors of light, temperature, nitrogen sources and water stress were analyzed quantitatively on the nodule formation and nitrogen fixation activity of autumn olive plant (Elaeagnu$ umbellala Thunb.) during the seedling growth. Seedlings showed the maximum nitrogenase activity of $72.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ in the early nodulation stage. The relative growth rate and T/R ratio changed from $1.60%{\cdot}d^{-1}$ and 1.12 in the earlier stage to $3.75%{\cdot}d^{-1}$ and 2.31 in the later stage, respectively. light conditions of 20-25, 1015 and 4-6% resulted in decreases of 41, 54 and 71% of the nitrogenase activity, respectively. Nodules incubated in 15, 20, 25 and $30^{\circ}C$ showed the activities of 5.4, 24.7, 51.6 and $58.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ respectively. Pretreatment with low temperature ($15^{\circ}C$) followed incubation at $30^{\circ}C$ attained higher nitrogenase activity ($66.5\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$) than that with higher temperature ($35^{\circ}C$). The oxygen pressure above 16 kPa is necessary for saturation of the nodule activity, but the activity was inhibited severely by physical impact such as the exision or isolation of nodules from the root. The relative activities of early nodules grown in pH 5.5, 6.5 and 8.0 were 89, 100 and 40% and those grown in 1 and 3 mM of $NO_3\;and\;NH_4$ were 6, 1 and 68, 50%, respectively. Watering levels of 20, 50 and 100 mL during the seedling growth resulted in 35, 120 and 8 mg of nodule formation and 33.6, 58.4 and $8.4\;\mu\textrm{M}\;C_2H_4{\cdot}g\;fr\;wt\;nodule^{-1}{\cdot}h^{-1}$ of the nitrogenase activity, respectively. Water stress with 86% decrease of soil water content caused temporary wilting point of leaf and a complete disappearance of nitrogenase activity of nodules, though the water content and transpiration rate in plant were reduced to 90 and 53%, respectively.tively.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.34-39
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• 2001

The purpose of this study was to examine physical properties of the addition of green tea powder on bread flour and dough rheology of white pan bread. Three levels(0.1, 0.5 and 1.0% ) of each green tea powder with bread flour were tested for their effects in dough mixing using rapid disco analyzer, alveogram and farinogram. Addition of green tea powder tended to reduce initial pasting temperature and increase peak viscosity, break down and set back. L(extensibility) and G(swelling index) value in alveogram showed decrement with increasing green tea powder. These meant that the volume of white pan bread would show same tendency. The use of green tea powder increased consistency and water absorption of the bread flour but decreased development time, salability and degree of softening on farinogram. White pan bread with green tea powder had higher value of hardness and springness than without it. Sensory evaluation determined that the white pan bread with 0.5% green tea powder had the highest score.

• The Korean Journal of Food And Nutrition
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• v.29 no.3
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• pp.438-447
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• 2016

This study was conducted in order to investigate the physiochemical properties and antioxidative activity of red ginseng manufactured using the high temperature high pressure (HTHP) process, which is faster and simpler than the conventional process. According to increasing the steaming temperature, pressure and time, the content of minor non-polar ginsenosides, such as Rg3, Rk3, Rh4, Rk1 and Rg5 gradually increased. Also, the contents of acidic polysaccharide, total phenolic compounds and maltol gradually increased. Based on the results of the physiochemical properties and appearance quality, the optimum conditions of HTHP process were estimated as $140^{\circ}C$, $3kg/cm^2$ in 20 min. The total phenolic compounds and maltol contents of the HTHP process red ginseng (1.0% and 2.49 mg%, respectively) were higher than those of conventional red ginseng (0.23% and 0.60 mg%, respectively). In addition, the antioxidative activity was investigated using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-aziono-bis(3-ethylbenzthiazoline-6-sulfonic acid)) radical scavenging activity. DPPH and ABTS radical scavenging activities of HTHP process red ginseng increased by 3.4 and 3.6 folds, respectively, compared with conventional red ginseng. In addition, total phenolic compounds and maltol contents, as well as the antioxidant activity of the HTHP process red ginseng were similar to black ginseng. The present results suggest that the HTHP process is available for the development of value-added red ginseng products.