• Korean Journal of Soil Science and Fertilizer
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• v.17 no.4
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• pp.375-380
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• 1984

A pot experiment was conducted to learn the effect of non-compounded and compounded (with super phosphate) liquid fertilizers made of amino acid fermentation by product and the time of their application on the emergences and yield of orchard grass. Results obtained as follows; 1. The Application of the liquid fertilizers, on seeding day of the orchard grass raised soil pH and salt concentration more than the application on the days before seeding and decreased the number of sprouts of the grass which also lead to a lower yield of the grass compared with the latter. 2. Liquid compound fertilizer, however, tended to reduce the harmful effect on sprouting orchard grass compared with non-compounded liquid fetilizer, particulary in soil of on-lime applied. 3. The application of liquid and liquid compound fetilizers on somewhat acidic bare land a quite ahead of seeding or transplanting crops may not only reduce the effect of the fertilizers, provided the land is free from washing by rain or irrigation water, but also provide better conditions for sprouting and early growth of plant seedings than the use at the pre-seeding or pro-transplanting time.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.98-105
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• 1983

Differences in fertilizer responses of Chinese cabbage to soil water status were investigated in a field experiment. The growth pattern, water use, nutrient uptake, apparent efficiency of fertilizer and yield were analyzed under the 4-different fertilizer levels (N-P-K rate, kg/10a: 0-0-0 Fo, 11.5-10-12.5 Fo.5, 23-30-25 F1.0, 34.5-30-37.5 F1.5 and under the 4-different soil water status levels (non irrigated plot Mo, -0.1 to -1.0 bars M1, -0.1 to -0.5 bars M2, -0.1 to -0.2 bars M3). The soil was Bonryang sandy loam in the experimental farm of the Institute of Agricultural Sciences, Suweon. The growth and yield responses to the fertilizer levels showed a large difference between F0 and F0.5 but little differences were recognized between F0.5, F1.0 and F1.5 when the soil water potentials at 20-cm soil depth were lower than -2.0 bar. Under the well irrigated soil conditions, M2, and M3, the growth and yield responses to the fertilizer levels were significantly increased and the nutrient requirements were increased as well. The total uptake of nutrients decreased as the fertilizer amounts increased when the soil water potentials were low, while the total uptake of nutrients increased when the soil water potentials were high. Therefore, in considering nutrient availability of the applied fertilizers, the soil water status should be taken into account.

• Korean Journal of Medicinal Crop Science
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• v.12 no.4
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• pp.295-299
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• 2004

This study was carried out to examine seed characteristics of Artemisia capillaris and the effects of different temperature and light on its seed germination, and of sowing date on its growth and yield. A seed of A. capillaris, 0.79 mm in length diameter, 0.39 mm in width diameter and 0.054 g in thousand-kernel weight, was extremely small, vertical pinstripes in the surface of seed, and long oval of dark brown in shape, and its maturity occurred September to October. A germination rate was superior at light conditions and 20 to $25^{\circ}C$ in temperature. Although its germination became shorter as the higher temperature. Its emergence rate was the highest in sowing at March 30. But the growth and yield potential was the best when sowed at March 20. The earlier the sowing date, the higher yield.

• Nuclear Engineering and Technology
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• v.10 no.4
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• pp.215-222
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• 1978

Using tracer technique of $^{65}Zn$, a field experiment has been carried out to evaluate the efficiency of zinc fertilizer by rice plant grown under flooded conditions. The treatments include zinc slufate mixed throughout the soil with and without organic matter, combined urea-zinc fertilizer (N: 37.7%, Zn: 3.1%), and surface application at transplaning and two weeks after transplanting at the rate of 5kg Zn/ha respectively. Other treatments were zinc sulfate mixed throughout the soil at the rate of 10 kg and 20 kg Zn/ha respectively. Root dipping in 2 % ZnO suspension, only organic matter added, and control were also included. There was not much difference in rough grain yield between zinc levels and different application methods, but the highest yield was obtained from the treatment of the root dipping in 2% ZnO suspension. Among the 5kg Zn/ha treatments, the highest total zinc yield was observed from the zinc mixed throughout the soil. The organic matter treatment seemed to reduce the zinc fertilizer efficiency. In case of the zinc fertilizer levels, 5kg Zn/ha mixed throughout the soil showed the highest zinc fertilizer efficiency as compared with 10kg and 20kg Zn/ha treatments.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.31-35
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• 2008

To elucidate optimum light conditions for artificial cultivation of Grifola frondosa, the effects of light quality (blue, green, white) and light intensity (200, 500, 800, 1200 lux) on primordium formation, morphological properties and yield of fruiting bodies of G. frondosa using bag cultivation method were tested. Among three light sources, white light source ($400{\sim}620\;nm$) had a higher mushroom yield (242 g/bag) and a shorter cultivation period (52 days) than those of the others. In particular, blue light source ($400{\sim}560\;nm$) induced the morphology of wide and deep colored pilei in G. frondosa fruiting body. The experimental results on the appropriate light intensity indicated that 500 lux light was the most effective on mushroom production, whereas primordium formation was effective at 200 lux.

• Resources Recycling
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• v.15 no.3 s.71
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• pp.46-57
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• 2006

This study was carried out for the purpose of recovering the refined gypsum from waste phosphogypsum. The refined gypsum was recovered as a under product of 325 mesh wet screening followed by dehydration and hydration stage. The influence of dehydration temperature and time, dehydration rate, aging time, slurry density of hydration and sonication time on the yield and grade of gypsum were investigated. The refined gypsum of $94{\sim}96%$ grade is recovered in 95% yield by wet screening after selective dehydration and hydration process, from the phosphogypsum. For the better separation efficiency of gypsum, it is recommended to treat the phosphogypsum at the conditions of as follows; 6hr's dehydration at $140^{\circ}C$, hydration slury density of $3{\sim}10%$, hydration temperature of $20{\sim}30^{\circ}C$, hydration time of 2hr. In additions, addition of sodium citrate 0.005M and sonication of $5{\sim}10min.$ are effective for increase the recovery of gypsum. On the other hand, aging the dehydrated gypsum 16 hours or longer make decrease the recovery of gypsum remarkably.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.142-150
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• 2020

This experiment was conducted to set ideal harvest time for itallian ryegrass (IRG) seed in reclaimed land. For IRG 'Kowinearly' variety sown in both autumn and spring, the peak growth in reclaimed land occurred in 20-30 days after heading. Plant height of IRG seedings in the spring was 90.4% of the fall-sown's plants. The yield of IRG seeds in reclaimed land was generally lower than that of farm land due to poor growth conditions. After heading, the lodging and shattering increased gradually with time. The highest yield of seed in the fall-sown trial treatment was 238 kg/10a. However, in the spring-sown treatment, the highest yield reached 169 kg/10a, which was 71% that of the fall-sown treatment. To set optimum harvesting time for IRG seed, morphological changes in the plant, moisture content of seed, and germination rate were analyzed according to time series after heading. After heading, IRG stem color had turned pink in 18 days and seed color also changed after 20 days. Following 20-25 days after heading, the seed moisture content decreased to below 55% and germination rate increased to over 90%. Therefore optimum harvesting time for IRG 'Kowinearly' variety in reclaimed land was 20-30 days after heading because germination rate and yields were high and shattering percentage was low.

• Applied Biological Chemistry
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• v.16 no.3
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• pp.128-136
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• 1973

An experiment was carried out to study the effects of Zn application on the rice plant of IR-667 and Jinheung varieties grown under the conditions of poor drainage and low available Zn. The results obtained were an follows; 1. The poor drained condition of the paddy field was more favorable for Zn utilization by the rice plants than the well drained condition. Also Zn application in the form of Zinc chloride $(ZnCl_2)$ seemed to significantly increased the rice yield of both IR-667 and Jinheung. 2. Zn content of IR-667 was much higher than that of Jinheung. The concentration of Zn in IR-667 rice plant treated by Zn fertilizer was about 200 ppm while that of control plot (not received Zn fertilizer) only 30 ppm. This result suggests that Zn application might improve the yield under the condition of poor drained soil when Zn concentration of IR-667 rice plant is around 30 ppm. 3. Absorption of Zn-65 by the rice plant was greater in the plants grown without Zn fertilizer than those with Zn fertilizer application, At harvest, the higher amount of Zn-65 was accumulated in the gram than in the straw. 4. Zn fertilization increased the grain yield in the soil of Paju, Dalsung, Chilg ok and Chungwon with low available Zn.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.1
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• pp.25-31
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• 2009

An analytical method of $^{99}Tc$ concentration in soil was set up and discussed considering the $^{99}Tc$ concentration in Korean soil measured with its analytical method. A selective TEVA resin was used to separate and purify the $^{99}Tc$ in the soil sample. $^{99m}Tc$ from a commercial $^{99}Mo/^{99m}Tc$ generator was used as a yield tracer for the chemical separation of $^{99}Tc$ and its problem when using $^{99m}Tc$ as a tracer was discussed. The chemical recovery yield of $^{99}Tc$ was above 70%. The optimum conditions of inductively coupled plasma mass spectrometry system(ICP-MS) were set up to determine the $^{99}Tc$ after the separation process. The minimum detectable activity(MDA) was 15 mBq/kg-dry in this analytical procedure. The $^{99}Tc$ concentration in soils of Jeju and Kori were measured in the rage of 33.73-89.16 mBq/kg-dry. Those values were less than those reported in other countries and seemed to be originated from atmospheric fallout.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.285-291
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• 2007

Enantioconvergent hydrolysis process for the preparation of chiral diol from racemic epoxides by using the recombinant Caulobacter crescentus epoxide hydrolase (CcEH) in Escherichia coli BL21 (DE3) was optimized. For the optimization, the effects of detergent, temperature and product inhibition on the enantiopurity and the yield of diol were investigated. (R)-phenyl-1,2-ethanediol with 92% enantiomeric excess and 56% yield from 20 mM racemic styrene oxide was obtained by using the recombinant CcEH at the optimal condition of $10^{\circ}C$ and the addition of 2% (w/v) Tween 80. At 50 mM racemic styrene oxide was used as a substrate, (R)-phenyl-1,2-ethanediol was obtained with 87% enantiomeric excess and 77% yield. Racemic phenyl-1,2-ethanediol, (R)-phenyl-1,2-ethanediol and (S)-phenyl-1,2-ethanediol dramatically inhibited the hydrolytic activity of the recombinant CcEH. These results suggested that another EH with the regioselectivity on ${\beta}$-position of (R)-enantiomer and without feedback inhibition by products would be needed as the partner EH of C. crescentus EH.