• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.1
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• pp.1-15
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• 2014

The cultivation situation of Korean wheat of 175 farmers in nationwide for two years, 2010/2011 and 2011/2012, was analyzed to obtain basic data for extension cultivated area and enhancing the self-sufficiency ratio of Korean wheat. Compared to the mean temperature and precipitation in the normal year, the mean temperature was lower before the heading stage and higher amount of precipitation after the heading stage in 2010/2011 and higher the mean temperature and lower amount of precipitation after the heading stage in 2011/2012. Average cultivation career and area were 7.7years and 2.4~3.3ha, Keumkang cv. was mainly cultivated for two years and Jokyung and Baekjoong cvs. were increased cultivation areas in southern part of Korea, Gyeongsangnam-do, Jeolllanambuk-do and Kwangju metropolitan city, including in 2011/2012. Most farmers (144) sown wheat seeds from late October to the beginning November with broadcasting method and the other famers were sown using the drill method. Average amount for basal fertilizer was 29.7 kg/10a with complex fertilizer mixed for wheat and barley cultivation, which was higher amount compared to recommended rate of fertilizer amount by rural development administration. Top dressing using nitrogen fertilizer was applied from in the late February to the beginning March. Heading date was the beginning May in 2011 and the late April in 2012, which the mean temperature from regeneration stage to tillering stage in 2011 was higher than that of 2012. Most farmers harvested wheat in mid-June and Pre-harvest sprouting and Fusarium head blight were occurred in 2011 due to the high amount precipitation during grain filling period.

• 한국해양학회지
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• v.23 no.4
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• pp.194-206
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• 1989

Seasonal variations of nutrients (ammonium, nitrite, nitrate, phosphate and silicate), primary productivity and ammonium regeneration rate of macrozooplankton were investigate to understand the relationship between nitrogen recycling and nitrogen requirement by phytoplankton from Feburuary 1986 to November 1987 in the Kyunggi Bay, shallow estuarine water of Yellow Sea. In general, nutrients increased during the winter and depleted during the spring and the early summer except temporally sharp increase after flood in September. Ammonium was prevalently generally found in high concentration throughout the study area and it occasionally raised N/P ratio in the range of 30 to 70 as in the freshwater environment. Daily net primary productivity ranged from 30.3 to 3580.0 mgC/$m^2$/d with an average of 883.9 mgC/$m^2$/d. Annual primary productivity was determined to be 320.0 gC/$m^2$/yr. Carbon assimilation number ranged from 2.9 to 19.4 mgC/mg chl-a/h which increased in the summer and decreased in the winter. Nitrogen requirement by phytoplankton ranged from 0.4 to 45.0 mg at-N/$m^2$/d and turnover time of inorganic nitrogen ranged from 2.4 in the late summer to 122.7 days in the winter. Nitrogen regeneration rate of mixed macrozooplankton determined by bottle incubation method ranged from 0.02 to 1.34 mg at-N $m^2$/d and it could contribute from 2.8 to 38.7% with an annual average of 14.9% of total nitrogen requirement by phytoplankton in this shallow estuarine environment.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.4
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• pp.221-226
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• 1973

In order to investigate the silica effect of insufficient wollastonite to the official standard (above than 15% of suluble silica (N/2 HCl) on rice plant as silica fertilizer, 9 kinds of wollastonites and slag were adopted to examine the amount of silica absorbed by rice straw during growing period, and soluble silica of wollastonites extracted by 7 buffer solutions were compared with silica content in rice straw. Crystalls of ingredient in wollastonite ores were identified by X-ray diffractometer. The results were that silica content of rice plant at growing stages were increased as same ratio of soluble silica. content in wollastonite. Wollastonite containing more than 10% of souble silica (N/2 HCl) could be applied as fertilizer because absorbed amount of silica by rice plant from them are higher than from slag which contained 30% of soluble silica. Wollastonite powder mixed with impure ores in which soluble silica could not be extracted had the same effect on silica absorption of straw as wollastonite powder which contained conformable amount of soluble silica. The soluble silica of wollastonite extracted by buffer solutions (2% citric acid, N. NaOAc, N. $NH_4OAc$, Petermann solution, 0.1M. EDTA, and Hot water) had high significant relation to silica content in rice straw, but soluble silica extracted N/2 hydrochloric acid solutilon, also, had deep relation to them in rice straw. The adequate solution to extract silica from wollastonites is N/2 hydrochloric acid solution because its extracted silia amount is much higher than other solution (about one hundred times) and can be determined by gravimetric analysis. X-ray diffraction pattern would identify qualitatively purity of wollastonite, and large amount of soluble silica was extracted from wollastonite which was appeared to be weathered.

• Journal of Bio-Environment Control
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• v.27 no.2
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• pp.173-179
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• 2018

Investigation of the optimum levels of pre-plant nitrogen for raising of hot pepper (cv. Nokkwang) plug seedlings was the objective of this research. To achieve this, the pre-plant nitrogen levels were varied to 0, 100, 250, 500, 750, 1,000, and $1,500mg{\cdot}L^{-1}$ and the other essential nutrients were controlled to equal concentrations in all treatments. All the fertilizers were added during the formulation of the mixed medium of coir dust, peatmoss, and perlite with the ratio of 35, 35, and 30% (v/v/v). The root medium containing pre-plant fertilizer was packed into 50-cell plug trays and seeds were sown. The measurement of pH and EC in every week, soil solution analysis for nutrients in week 0, 3, and 7 and growth measurements as well as tissue analysis for nutrient contents in week 7 were conducted. The pHs measured before seed sowing did not show significant differences, but the differences among treatments became significant as seedlings grow bigger. The soil solution ECs were significantly different among treatments in week 0 and these differences were diminished by degrees after week 3, resulting in no significant differences among treatments in week 7. The trends in changes of $NH_4-N$, $NO_3-N$, and other the macro-element concentrations in soil solution of root media were similar to those of ECs. The treatments of 500 and $750mg{\cdot}L^{-1}$ N were more effective than other treatments on seedling growth. The seedling growths in the treatments containing higher N than $1,000mg{\cdot}L^{-1}$ and control were severely suppressed. The elevated pre-plant N concentrations in the root medium resulted in the increase of tissue N contents. The treatments of 500 and $750mg{\cdot}L^{-1}$ N shown the highest seedling growths had 5.13% and 5.31%, respectively, in tissue N contents based on the dry weight of above ground tissue at week 7. The results of this study indicated that the optimum level of pre-plant N is 500 to $750mg{\cdot}L^{-1}$ for the raising of hot pepper plug seedlings.

• Journal of Korean Society of Forest Science
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• v.51 no.1
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• pp.41-50
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• 1981

The purpose of this study was to evaluate the substitutional possibility of new extender instead of wheat flour, which is extending for plywood adhesives in Korea. As the extending materials corn stalk, pine bark, Pitch and Korean pine leaves, wheat, or wood flour were selected and prepared for the extending powders, dried at $103{\pm}2^{\circ}C$ during 24 hours in the drying oven, followed by being pulverized into 60-100 mesh powder. The extenders were mixed with urea formaldehyde resin in the ratio of 5, 10, 15 or 20%. After plywoods were manufactured by the above extended ratios, dry and wet shear strength and wood failures were analyzed and discussed. The results at the study may be summarized as follows ; 1. In urea formaldehyde resin dry shear strength in plywood extended by wheat flour showed the highest value. 2. Among the extenders in 10 and 20% extension of urea formaldehyde resin wet shear strength of wood flour was higher than that of wheat powder. They had no significant difference statistically. 3. Among the extenders of 5% extension of water soluble phenol formaldehyde resin dry shear strength of plywood extended by Korean pine leaf powder showed the highest value, while wheat powder showed the highest value among 10, 15 and 20% extentions. 4. In water soluble phenol formaldehyde resin the best results of wet shear strength showed in wheat powder. 5. Among the extenders in 15 and 20% extension of water soluble phenol formaldehyde resin, dry and wet shear strength in plywood of corn stalk powder were the highest value next to wheat powder.

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.453-459
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• 1988

The purposes of this study were to evaluate the effects of acid rain on tree growth and on the mycorrhizal formation and the effects of mycorrhizae on the host tolerance to acid rain. Simulated acid rain was applied for five months to Pinus $rigida{\times}taeda$ seedlings in pots inoculated with Pisolithus tinctorius (Pt) and Suillus luteus (Sl). Mycelial inocula of Pt and Sl were either mixed with entire pot soil (Mix) or casted as a band (Band) after soil sterilization. Three pH levels of acid rain (pH 3.0, 4.5 and 6.4 adjusted by 3 : 1 mixture of sulfuric and nitric acids) were tested. Pt-Mix was most effective in growth stimulation and resulted in 45-90% increase in tree height in sandy loam. Pt-Band was less effective than Pt-Mix in growth stimulation and mycorrhizal formation. Simulated acid rain at pH 4.5 stimulated height growth by 10-55%, while acid rain at pH 3.0 did not significantly affect the height growth. The top/root ratio was increased by pH 4.5 treatment, while pH 3.0 treatment reduced it. Mycorrhizal infection rate was not affected by acid rain. Pt inoculation reduced acid-induced leaf injury by 28-58% in both pH 3.0 and 4.5 compared with un-inoculated plants. Sl was also effective in growth enhancement, but was less effective than Pt in both mycorrhizal infection and reducing leaf injury.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.347-354
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• 2004

Four Holstein cows were used in a 4 ${\times}$ 4 Latin square experiment to study effects of fat sources on rumen metabolism and digestibility of nutrients. All cows were fed a total mixed diets containing 60% silage and 40% concentrate. The four concentrates were formulated to contain either Megalac(MEG), formaldehyde-treated whole linseed(LIN), a mixture (50 : 50, oil basis) of fish oil and formaldehyde-treated whole linseed(MIX), or no fat source in the concentrate but 500g per day of linseed oil being infused into the duodemm (OIL). The rumen pH was lowest in OIL among the treatments(P < 0.05), but ammonia N concentration in the rumen was not significantly different among the treatments. The differences of total VFA, acetate, propionate, iso-butyrate and iso-valerate concentrations were not significant among the treatments. While, butyrate and valerate were highest in OIL and lowest in MEG(P < 0.05 and P <0.01, respectively). In addition, A:P ratio was also highest in OIL and lowest in MEG(P < 0.05). As expected, intake of nutrients(DM, OM, NDF and ADF) was lowest in OIL among the treatments(P < 0.01). However, all nutrients flow to the duodenum, and digestion in the rumen and total tract were not significantly different among the treatments. Intake of N was highest in MEG, but lowest in OIL treatment(P < 0.01). Duodenal flow of total N, nonammonia N and microbial N was not significantly different across the treatments. In addition, microbial synthesis and ammonia N and total N digestibility were not affected by different dietary fat sources. The present results show that fermentative characteristic and microbial efficiency in the rumen, and nutrients digestibility in the rumen and total tract were not depressed by supplementation of as much as 6% dietary fat sources.

• Journal of the Korean Society of Food Culture
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• v.6 no.2
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• pp.185-197
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• 1991

An eating behavior research was done with 50 females at a buffet styled restaurant during their lunch time. Of the respondents, 52.0% were professional and 54.0% were graduate school graduates. Of the respondents, 58.0% of the company were friends and 24.0% were relatives. The average time period of eating was $93.0{\pm}23.4$ minutes. The average frequency of taking food was $4.0{\pm}1.1$ and the average frequency of taking food after satiety was $1.4{\pm}0.8$. It is significant that lower frequency of food consumption was directly proportional to the age groups of respondents. The average selected food items were $30.4{\pm}7.1$ out of 175 and the average weight of the consumed food was $995.0{\pm}240.9$ g. The older age group chose a similar number of food items, but the amount of each food item was considerably less than younger. So the younger the age group was, the more they ate. The average food items at one time was $7.1{\pm}2.2$ and the average food weight time was $233.7{\pm}69.7$ g. The percentage of respondents who evaluated themselves as 'ate too much' was 70.0% and those who evaluate themselves 'ate properly' was 14.0%. Most of them were satisfied with the buffet service. The average of number of food items consumed by respondents before cooking was $50.5{\pm}8.9$. The consumption of calories and nutrients was compared with the Korean Daily Recommended Dietary Allowances. The consumed calories were 60.9% of RDAs, protein 104.4%, calcium 77.1%, iron 129.8%, vitamin A 66.5%, thiamin 96.0%, riboflavin 95.7%, niacin126.6% and ascorbic acid 112.3%. This data exceeded 1/3 of the Korean Daily RDAs tremendously and tells us extreme overeating. The energy ratio of carbohydrate: fat: protein was 51.6: 29.9: 18.5. Caloric consumption of animal food was 27.9% and the consumption rate of the other nutrients from animal food was considerably high. But the consumption rate of vitamin A was 90.9% from vegetable groups. Accoding to this study, buffet service gives some advantages. It gives customers an good opportunity to vary their food intake, which enhances eating experiences and can cause an improvemont of food habits. But overeating is a problem. Therefore, we think it is necessary for those women who have influence over their family's food selection, to have nutrition education about a desirable order of eating a meal, food selection, and health problems due to overeating at buffet styled restaurant. There should be some improvement in the management of buffet service. For example, proper temperature, texture, and freshness of the food should be maintained. Prevention of mixed food smells should be considered as well. To lower the price it is desirable to reduce the number of similar items and to use seasonal food as much as possible. A buffet styled restaurant with less food items with cheaper prices is recommended. Various traditional food should be developed for the menu items. We expect buffet services to be sutable to maintain good health and to be popular to any eater.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.116-123
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• 1974

1) In Seoul, it was known that the season for preparing Kimchies (fermented vegetables) for the winter was from the middle of November to early in December, in which the preparing rates of Kimchies in the middle of November, the end of November and early in December were 32.7%, 41.3% and 12.5%, respectively. The time that the largest quantity of them was prepared was about the end of November. 2) The average cost of Kimchies prepared for the winter for a family of four, five, six and seven was $10,000{\sim}15,000$ Won, $15,100{\sim}20,000$ Won, $10,100{\sim}20,000$ Won and $10,100{\sim}20,000$ Won, respectively, and the cost did not increase in proportion to members of a family. In case of the family of $6{\sim}7$, the cost for Kimchies showed a wide range compared with those for the family of $4{\sim}5$ 3) The main raw materials of kimchi for one person for the winter required $12{\sim}20$ heads of Chinese cabbages, $14{\sim}20$ roots of radishes, $4{\sim}7$ cloves of garlics and $300{\sim}500g$ of powdered red pepper. 4) The residents living in Seoul had prepared the several kinds of the pickles for the winter as follows; (1) Chinese cabbage Kimchi (98.9%), (2) Whole Chinese cabbage Kimchi (74.7%), (3) Kkakdugi (68.6%), (4) Dongchimi (66.4%) and (5) Chong-kak Kimchi (63.3%). It has, therefore. been considered that the five kinds of Kimchies mentioned above may be industrialized. 5) Uniqueness of the raw materials used for the most popular Chinese cabbage Kimchi was to use leeks, garlics, red peppers and gingers as spices, and it was also known that proper amounts of salted shrimp pickles and oysters was mixed to the Kimchies. Therefore, it had been considered that the characteristics of Chinese cabbage Kimchies for the winter had the hot taste with freshness. 6) For keeping the Kimchies during the winter about the half of the pickle jars was buried in the ground, and another half of them were wrapped in the straw bags or styropol and they were placed on the ground or kept in the basement, 7) In most case (80.9%), the salt concentration of pickling was adjusted by one's experiences, and only 19% of them was measured with the instruments. 8) Most of remaining kimchies were usually used for other cooks, but some of them were thrown away. 9) The ratio of the people who had ever bought the market Kimchies for their own edibility was 17.8% and most of them got it only in the spring and summer season. 10) About 18% of the residents living in the general houses in Seoul had ever bought the market Kimchies. It was also known that about 48% of the residents living in the general houses and about 79% of the residents living in the apartments wanted to purchase the market Kimchies if the production of the delicious Kimchies were industrialized. The season that the people wanted to get the market Kimchies was a little different each other among the residents. About 13.4% of the residents living in the general houses wanted to purchase the Kimchies during the summer, and 11.9% of them wanted to get it throughout the year. On the other hand, in case of the apartments, 25.2% of the residents wanted to get it during the summer and 24.4% of them wanted it throughout the year (4 seasons) and 19.9% of them wanted it during two seasons. The data mentioned above have shown that many residents hope strongly an industrial production of the Kimchies. It is also true that many residents living in both the general houses and apartments want to get the market kimchies throughout the year, and particulary during the summer season that most foods are very apt to be spoiled.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.8-11
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• 2012

Purpose : Among quality control items, the radiochemical impurity must be below 10% of total radioactivity. In this regard, as the recently commercialized automatic synthesis module produces a large amount of 18F-FDG, radiolysis of radiopharmaceuticals is very likely to occur. Thus, this study compared the changes in radiochemical purity regarding radiolysis of $^{18}F$-FDG according to automatic synthesis module. Materials and methods : Cyclotron (PETtrace, GE Healthcare) was used to produce $^{18}F$ and automatic synthesis module (FASTlab, Tracerlab MX, GE Healthcare) was used to achieve synthesis into FDG. For radiochemical purity, Radio-TLC Scanner (AR 2000, Bioscan), GC (Gas Chromatograph, Agilent 7890A) was used to measure the content of ethanol included in $^{18}F$-FDG. Glass board applied with silica gel ($1{\times}10cm$) was used for stationary phase while a mixed liquid formed of acetonitrile and water (ratio 19:1) was used for mobile phase. High-concentration and low-concentration $^{18}F$-FDG were produced in each synthesis module and the radiochemical purity was measured every 2 hours. Results : The purity in low-concentration (below 2.59 GBq/mL) was measured as 99.26%, 98.69%, 98.25%, 98.09% in Tracerlab MX and as 99.09%, 97.83%, 96.89%, 96.62% in FASTlab according to 0, 2, 4, 6 hours changes, respectively. The purity in high-concentration (above 3.7 GBq/mL) was measured as 99.54%, 96.08%, 93.77%, 92.54% in Tracerlab MX and as 99.53%, 95.65%, 92.39%, 89.82% in FASTlab according to 0, 2, 4, 6 hours changes, respectively. Also, ethanol was not detected in GC of $^{18}F$-FDG produced in FASTlab, while 100~300 ppm ethanol was detected in Tracerlab MX. Conclusion : Whereas the change of radiochemical purity was only 3% in low-concentration $^{18}F$-FDG, the change was rapidly increased to 10% in high-concentration. Also, higher radiolysis were observed in $^{18}F$-FDG produced in FASTlab than Tracerlab MX. This is because ethanol is included in the synthesis stage of Tracerlab MX but not in the synthesis stage of FASTlab. Thus, radiolysis is influenced by radioactivity concentration than the inclusion of ethanol, which is the radioprotector. Therefore, after producing high-concentration $^{18}F$-FDG, the content must be diluted through saline to lower concentration.