• Korean Journal of Soil Science and Fertilizer
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• v.11 no.1
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• pp.17-24
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• 1978

A field experiment was conducted on a soil where habitual zinc deficiency has been observed, to investigate the effectiveness of two forms of zinc containing fertilizers: zinc enriched fused phosphate and zinc enriched compound fertilizer. The result of present study is summarized as following. 1. The sail used for the study contained relatively large amount of 1N $CH_2COONH_4$ extractable Ca and the pH was 7.03. Available Zn extracted by 0.1 HCl and available $SiO_2$ extracted by NaOAc were 3.35 ppm and 67.7 ppm respectively. 2. In control plots Zinc content of rice plant measured at 20 days after transplanting was 22-23 ppm, which was a little higher than the critical level (20ppm). But at harvesting stage it dropped to 15ppm. 3. The ratios of $P_2O_5/Zn$ and N/Zn tended to lower as the zinc applied to the soil increased. 4. Application of Zinc clearly increased the number of tillers and plant height as compared to the control. It was also observed that the plots received znic headed and matured earlier compared to the control plots by two weeks. 5. Application of zinc increased all of the yield components and the yield of rice. However, there were no statistical differences in yield and yield components among the forms and levels of zinc fertilizers.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.3
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• pp.162-168
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• 2002

The silica uptake of rice plant(Oryza sativa L.) and a potential capacity of paddy soil as a source of silica supply for rice plant was studied under field experimental condition. Amount of Si from irrigation water, rainfall, which was a source of silica supply, and percolating rate of water through paddy soil profile as a source of silica loss from paddy soil, was investigated. Rice plants were grown in three different conditions, which included Control as non-fertilized, RDA's recommandation(NPK, Urea-Fused phophate-Potassium chloride=$110-45-57kg\;ha^{-1}$) and RDA's recommandation with supplement of silicate fertilizer(NPK+Si, Urea-Fused phosphate-Potassium chloride+Si=$110\;N-45\;P_2O_5-57\;K_2O+267.2\;Si\;kg\;ha^{-1}$). An amount of silica supply from rainfall was $0.5kg\;ha^{-1}$ and average amount of silica supplied from irrigation water $42.5kg\;ha^{-1}$, ranging from $28.1kg\;ha^{-1}$ to $58.8kg\;ha^{-1}$. Silica amount percolated through the soil profile have uniform trend comparatively showing $62.9kg\;ha^{-1}$ in Control, $64.8kg\;ha^{-1}$ in NPK treatment and $62.9kg\;ha^{-1}$ in NPK+Si treatment. Silica uptaked by Rice plant was $335.6kg\;ha^{-1}$ in Control, $406.6kg\;ha^{-1}$ in NPK+Si treatment and $471.1kg\;ha^{-1}$ in NPK+Si treatment. The difference between an amount of Si input(from rainfall, irrigation water and silicate fertilizer) and an amount of Si output(percolated Si in soil, uptaked Si by rice plant) was $357.4kg\;ha^{-1}$ in control, $412.1kg\;ha^{-1}$ in NPK treatment and $238.2kg\;ha^{-1}$ in NPK+Si treatment. Results of our study imply that paddy soil is a potential pool as a source of Si supply during growing periods of rice plant.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.283-288
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• 1984

This study was conducted to evaluate the characteristics of exothermic heat and compost generated from decomposition of organic wastes composts were piled up with various sources of raw materials of rice straw, rice husk, human and animal wastes. The duration of generated exothermic heat during compositing process was longer in mixture piles of rice straw/rice husk ratio of 1:1 compared to rice straw alone. Temperature in compost piles added with phosphate as fused superphosphate fertilizer was rapidly increased at the earlier stage of composting and gradually decreased in 30 days compared to the check. pH of compost showed 5.5 at initial piling, however, its peak appeared 8.8 in 10 days with rapidly increasing temperature of compost and maintained around 8.3 after one month. Compost of mixture of rice straw and chicken droppings maintained temperature ranges of 30 to $65^{\circ}C$ for 39 days, compost of rice straw, rice husk and chicken droppings for 69 days, piles of rice straw, rice husk and hog manure for 56 days, mixture of rice straw, rice husk and cow manure for 66 days and compost of rice straw, rice husk and human wastes for 21 days.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.265-272
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• 2008

Toxicity of 10 registered insecticides and 6 fertilizers were tested against $3^{rd}$ larva and adults of Korean firefly, Luciola lateralis Motschulsky(Coleoptera: Lampyridae). All experiments were tested at the recommended concentration of each inescticides by producer. MEP, PAP, Acephate, Fenthion, and Diazinon, which were organophates, a mixtures combined with Burofezin fenobucarb, Cartap buprofezin, and Thiamethoxam(Neonicotinoids), Fipronil(Phenylpyrazoles) showed more 80.0% mortality on larva and adults of L. lateralis. However, tebufenozide(I.G.R) showed low mortality of 33.3%. $LC_{50}$ (ppm) value of Assit, Cartap buprofezin, Fenthion and PAP were showed 1.03 ppm, 1.90 ppm, 10.26 ppm, 0.98 ppm, respectively, against $3^{rd}$ larva of L. lateralis. Effects against eggs showed very high toxicity. Otherwise, tebufenozide(I.G.R) was showed hatchability of 100%. Toxicity of Urea fertilizer, Ammonium sulfate, Potassium chloride, Fused phosphate, Complex fertilizer and Silicate fertilizer were showed the mortality with 27.3%, 56.7%, 73.3%, 0.0%, 0.0%, 0.0%, respectively, when exposed 72 hrs after treatment.

• The Journal of Korean Academy of Prosthodontics
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• v.22 no.1
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• pp.33-50
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• 1984

The purpose of this study was to investigate whether the ashed tooth powder is utilized as an alternative material of the implant to recovery the bony defect. For this purpose its biocompatibility was evaluated comparing to the synthetic calcium phosphate compounds, such as Syntograft and Calcitite, as well as the vacuum firing porcelain (Ceramco Inc.) which is anticipated to use as a matrix to aid sintering. Bony defects to exposure the bone marrow, $3{\times}5$ mm in size, were created in the right and left tibias of fifteen rabbits, and then the ashed tooth powder at $950^{\circ}C$, the porcelain powder, Syhtograft and Calcitite were inserted in the defects of twelve rabbits of the experimental group and the blood clot only was filled in the defects of three rabbits of the control group. The experimental and control rabbits were sacrificed at 1st, 2nd 3rd week after implantation and the histologic examination was performed. The ashed tooth powder in order to make the needed form of the implant was molded using the cylindrical mold 1 cm high, 1 cm in diameter under the pressure of $1000kg/cm^2$ and the ashed tooth powder was sintered at $1100^{\circ}C$ for 1 hour and the mixture of the porcelain powder and the ashed tooth powder at the weight ratio of 7:3, 6:4, 5:5, 4:6 were molded in the same manner and were sintered at $925^{\circ}C$. From this sintered material, square shaped implants were prepared in the dimension of $2{\times}4{\times}6mm$. The prepared implants were surgically placed in the subperiosteum of lateral surfaces of the right and left mandibular bodies. The dogs were sacrificed at 4 weeks, and then the specimens were examined using the light and scanning electron microscopes. The results of this study were obtained as follows: 1. Any inflammatory response was not noted after implanting of the ashed tooth powder, Syntograft, Calcitite and the porcelain powder during the whole experimental period after implantation. 2. Induction of the new bone formation was significantly shown in the ashed tooth powder, Syntograft and Calcitite. 3. The more the porcelain powder was contained in the implants, the more the porosity was and the bigger the pore size was under the scanning electron microscope. And there was ingrowing of the fibrous connective and the osteoid tissue. 4. The osteoid tissues were found to be directly fused to the implant of the ashed tooth powder, and the mixture implant of the porcelain powder and the ashed tooth powder at the weight ratio of 4:6 under the light and scanning electron microscopes.

• Analytical Science and Technology
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• v.9 no.1
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• pp.35-42
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• 1996

A rapid analytical method based on capillary electrophoresis is described for the determination of trace anions in high-purity chemicals which is used to prevent corrosion demage in nuclear power plants. Separations are carried out at 20kV using trimethylsilane-coated fused-silica capillary ($70cm{\times}50$ or $75{\mu}m$ i.d.) with the electrolyte of 5mM Chromate(pH=8). Detection was achieved using on-column indirect photometry at 254nm. The simultaneous analysis of inorganic anions, chloride, nitrate, sulfate, azide and phosphate was performed using methods of hydrodynamic(>1ppm) and / or electrokinetic(<1ppm) injection. The results of studies on the coexisting anions on analyte ions shows that peak responses of analyte in hydrodynamic injection is constant without effect of coexisting anions, but those of analysis in electrokinetic injection is strongly dependant upon the kind of coexisting anions and its ionic mobility. The analyte enrichment rate, hence peak response, is positive relationship with the resistance of the sample solution. Thus, appropriate measures, such as standard addition or internal standard technique, must be used to account for differences in conductance of standard and sample solutions.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.159-164
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• 1991

A field microplot(D 20cm, L 85cm) experiment filled with Bonryang sandy loam soil (Typic Udifluvents) was conducted to obtain quantitative information on the movement of applied nutrients under diffetent soil moisture regimes and ladino clover cultivation. Chloride moved rapidly with soil water. When soil moisture tension was maintained at loer than 0.2 bar most of the Cl appeared to move outside the microplot 4 month after the microplot installation. Regardless of soil moisture condition, Cl was not detected in the soil due to the fast movement of the Cl beyond the microplot after 5.5 months Although large amount of P and water were applied to the soil of high available P during the field experiment, movement of P was negligible and most of P remained in thc place where applied due to the low solubility of the fused and superphosphate. Phosphate in the soil extracted by Bray No.1 solution and taken up by plant increased with soil moisture. Under the condition of irrigation at 0.2 bar, plant took up 23% of the applied P, and 24% of the P was extracted by Bray NO.1 solution, while plant took up 14% and 13% of the P was turned out to be Bray No.1 P. at thc nonirrigated condition after final harvest.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.3
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• pp.153-160
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• 1975

Jeju island has high potential productivity of livestock in terms of climate, geography, and economic prospect. Grass-land is now widespread and increasing rapidly year after year. However, the productivity of grass land is very low compared with that of main land. It is supposed that the low productivity is due to improper chemical properties of volcanic ash soil which is mostly distributed in the island. Volcanic ash soil, which have high alumina ratio, is characterized by the lack of bases and avilable phosphorous while its phosphorous fixation capacity is very high. In addition to poor chemical properties, low level of fertilization technique appears to be another limitation to grass production. Farmers have not given care to improve their soil to be suitable for grass cultivation. In order to increase the productivity of grassland in Jeju, the proper amounts of N, P, and K fertilizer should be applied following the improvements of poor chemical properties such as liming and a great deal of phosphorous increment, using mainly fused phosphate, based upon the balance of bases, and the application of organic matter and micro-elements which can be easily deficient in soil.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.2
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• pp.71-76
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• 1976

Field experiments were conducted to study the effect of amendments such as lime and organic matter for mulberry trees on the newly reclaimed sandy loam soil for three years. The results are summarized as follows. 1. Compared to the N.P.K check plot with treatments, leaf yield was increased by 20 to 80%. Leaf yield was higher in the order of NPK+magnesia lime < NPK+compost > NK+fused phosphate NPK+green manure > NPK+barley straw> NPKplot. 2. Mulberry leaf yield showed high significant positive correlation with total weight and volume of root, length and number of wattles and the content of CaO or MgO in leaf respectively. 3. It is known that dead part sympom of top branch during cold season is associated with unbalance magnesium to potassium in mulberry leaf. It is estimated that such symptom was deminished when the ratio of $K_2O/MgO$ in leaf becomes 6.0 or higher. 4. In establishing a mulberry field on hilly reclaimed soil, application of magnesium and calcium with compost was essential but higher amount of potassium fertilizer should be followed in order to prevent dead part symptom of top branch of mulberry trees.

• Journal of Embryo Transfer
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• v.10 no.1
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• pp.65-72
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• 1995

The purposes of this study were to produce cloned rabbit embryos and offsprings by nuclear transplantation(NT) using in vitro matured oocytes as nuclear recipient cytoplasm and to determine the effect of frozen nuclei donor embryos on the production efficiency of cloned embryos. The 8cell embryos were collected from the mated does by flushing oviducts with Dulbecco's phosphate buffered saline containing 10% fetal calf serum(FCS) at 40 hours after hGG injection. A portion of collected embryos were preserved at 4$^{\circ}C$ for 24 hours and a portion of them were frozen by vitrification method. The embryos used for donor nuclei were synchronized in the phase of Gi /S transition. The in vitro matured oocytes were used as recipient cytoplasm following removing the nucleus and the first polar body. The synchronized blastomeres from fresh, cooled or frozen embryos were injected into the enucleated oocytes by micromanipulation and were electrofused by electrical stimulation of three pulses for 60 $\mu$sec at 1.0 W /cm in 0.28 M mannitol solution. The fused oocytes were co-cultured with a monolayer of rabbit oviductal epithelial cells in M-199 solution containing 10% FCS for 120 hours at 39$^{\circ}C$ in a 5% $CO_2$incubator. Following in vitro culture of the NT embryos to blastocyst stage, they were stained with Hoechst 33342 dye for counting the number of blastomeres by fluorescence microscopy. The nuclear transplant embryos developed in vitro to 2- to 4-cell stage were transferred into the oviducts of synchronized recipient does. The results obtained were summarized as follows: 1. The fusion rates of the blastomeres from fresh, cooled and frozen embryos with the in vitro matured and enucleated oocytes were 100, 95.8 and 64, 3%, respectively. 2. Development in vitro to blastocyst was significantly(p<0.05) different between the cloned embryos with the blastomeres from fresh, cooled or frozen embryos as 39.0, 20. 9 and 15.7%, respectively. 3. The mean numbers of cell cycle per day during in vitro culture of cloned embryos blastomeres from fresh, cooled or frozen embryos was 1.31, 1.29 and 1.16, respectively. 4. A total of 77 nuclear transplant embryos were transferred into 6 recipient does, of which two offsprings were produced from a foster mother 31 days after embryo transfer.